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Szczygiel LA, Greene AK, Cutter CM, Jones RD, Feldman EL, Paradis KC, Settles IH, Singer K, Spector ND, Stewart AJ, Ubel PA, Jagsi R. Professional Experiences and Career Trajectories of Mid- to Senior-Career Women Clinician-Scientists: A Qualitative Study. JAMA Netw Open 2024; 7:e246040. [PMID: 38602674 DOI: 10.1001/jamanetworkopen.2024.6040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 04/12/2024] Open
Abstract
Importance Despite increasing evidence and recognition of persistent gender disparities in academic medicine, qualitative data detailing the association of gender-based experiences with career progression remain sparse, particularly at the mid- to senior-career stage. Objective To investigate the role gender has played in everyday professional experiences of mid- to senior-career women clinician-scientists and their perceptions of gender-related barriers experienced across their careers. Design, Setting, and Participants In this qualitative study, a total of 60 of 159 invited clinician-scientists who received National Institutes of Health K08 or K23 awards between 2006 and 2009 and responded to a survey in 2021 agreed to participate. Invitees were selected using random, purposive sampling to support sample heterogeneity. Semistructured in-depth interviews were conducted January to May 2022. For this study, interviews from 31 women were analyzed using the framework approach to thematic analysis. Data analyses were performed between August and October 2023. Main Outcomes and Measures Descriptive themes of participant experiences of gender and gender-based barriers in academic medicine. Results A total of 31 women clinician-scientists (8 identifying as Asian [25.8%], 14 identifying as White [45.2%], and 9 identifying as members of a minority group underrepresented in medicine [29.0%]; 14 aged 40-49 years [45.2%] and 14 aged 50-59 years [45.2%]) were included. Among them, 17 participants (54.8%) had children who required adult supervision or care, 7 participants (22.6%) had children who did not require supervision or care, and 6 participants (19.4%) did not have children. There were 4 dominant themes identified within participant experiences in academic medicine: the mental burden of gendered expectations at work and home, inequitable treatment of women in bureaucratic processes, subtle and less subtle professional exclusion of women, and value of communities built on shared identities, experiences, and solidarity. Conclusions and Relevance This study found that women perceived the institution of academic medicine as a male-centric system misaligned with the needs of women, with associated feelings of exclusion, disillusionment, and loss of trust in their institutions. Findings suggest that the confluence of domestic obligations and unaccommodating institutional environments may make it difficult for women clinician-scientists to achieve established timelines of career progression and productivity; these findings may have long-term implications for the well-being and retention of women in academic medicine.
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Affiliation(s)
| | - Amanda K Greene
- Center for Bioethics and Social Sciences in Medicine, University of Michigan Medical School, Ann Arbor
| | - Christina M Cutter
- Department of Emergency Medicine, University of Michigan Medical School, Ann Arbor, Michigan
| | - Rochelle D Jones
- Department of Radiation Oncology, Emory University, Atlanta, Georgia
| | - Eva L Feldman
- Department of Neurology, University of Michigan Medical School, Ann Arbor
| | - Kelly C Paradis
- Department of Radiation Oncology, University of Michigan Medical School, Ann Arbor
| | - Isis H Settles
- Department of Psychology, University of Michigan, Ann Arbor
- Department of Afroamerican and African Studies, University of Michigan, Ann Arbor
- Department of Women's and Gender Studies, University of Michigan, Ann Arbor
| | - Kanakadurga Singer
- Department of Pediatrics, University of Michigan Medical School, Ann Arbor
| | - Nancy D Spector
- Department of Pediatrics, Drexel University College of Medicine, Philadelphia, Pennsylvania
| | - Abigail J Stewart
- Department of Psychology, University of Michigan, Ann Arbor
- Department of Women's and Gender Studies, University of Michigan, Ann Arbor
| | - Peter A Ubel
- Duke University School of Medicine, Durham, North Carolina
| | - Reshma Jagsi
- Department of Radiation Oncology, Emory University, Atlanta, Georgia
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Jacobson CE, Griffith KA, Krenz C, Jones RD, Cutter CM, Singer K, Paradis KC, Stewart AJ, Feldman EL, Settles IH, Kerr EA, Ubel PA, Spector ND, Jagsi R. The Disproportionate Effects of the COVID-19 Pandemic on the Time Allocation of Recipients of NIH Career Development Awards Who Are Women or Caregivers of Dependents. Acad Med 2024:00001888-990000000-00787. [PMID: 38452218 DOI: 10.1097/acm.0000000000005681] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 03/09/2024]
Abstract
PURPOSE To understand time allocation of a national medical faculty cohort 1.5-2 years after the COVID-19 pandemic began, compared to before. METHOD From August 2021-April 2022, the authors conducted a retrospective survey of 1,430 clinician-researchers who received National Institutes of Health career-development awards between 2006-2009 asking about domestic and professional time allocation pre-pandemic and at the time of surveys (TOS). Of 915 respondents (64%), the 830 who remained in academic positions constituted the analytic sample. Multivariable regression models identified demographic factors associated with each time outcome and change in time between pre-pandemic and TOS, and having experienced ≥8-hour increase of total self-reported weekly professional work hours and domestic labor hours. RESULTS Median self-reported weekly professional work hours were 55 hours/week pre- pandemic and 60 at TOS. On multivariable analysis, significant predictors of self-reported weekly professional work hours at TOS were having a non-child other dependent (+2.6 hours, P = .03), academic rank (associate -3.1 hours, assistant -9.0 hours; P < .001), and specialty (P < .001). Average self-reported TOS weekly domestic-labor hours were 23.1 among men and 30.2 among women (P < .001). Predictors of total self-reported TOS weekly domestic hours were being a woman (+5.6 hours; P < .001) and having children requiring supervision (+10.2 hours; P < .001). Overall, 9.3% of men (42/450) and 21.6% of women (88/407) experienced a ≥ 8 hour increase in domestic labor (P < .001). On multivariable analysis, women had higher odds of substantial domestic-labor increase (OR = 2.33, 95% CI: 1.47, 3.68), as did those with children requiring supervision (OR = 1.93, 95% CI: 1.25, 2.98) or other dependents (OR = 1.83, 95% CI: 1.13, 2.98). CONCLUSIONS This study illuminates demands on women and faculty with dependents during the COVID-19 pandemic and suggests increased flexibility and resources are of heightened importance.
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Affiliation(s)
- Clare E Jacobson
- C.E. Jacobson is a general surgery resident at the University of Michigan, Ann Arbor, Michigan
| | - Kent A Griffith
- K.A. Griffith is a statistician at the Center for Cancer Biostatistics, University of Michigan School of Public Health, University of Michigan, Ann Arbor, Michigan
| | - Chris Krenz
- C. Krenz is a student at Boston University, Boston, Massachusetts
| | - Rochelle D Jones
- R.D. Jones is a Research Area Specialist Senior at the Center for Bioethics & Social Sciences in Medicine, University of Michigan, Ann Arbor, Michigan
| | - Christina M Cutter
- C.M. Cutter is an Assistant Professor of Emergency Medicine at the University of Michigan, Ann Arbor, Michigan
| | - Kanakadurga Singer
- K. Singer is the Valerie Castle Opipari Professor of Pediatrics, Assistant Dean for Tenure Track Faculty in the Medical School, Associate Professor of Pediatric Endocrinology at the University of Michigan, Ann Arbor, Michigan
| | - Kelly C Paradis
- K.C. Paradis is an Associate Professor of Medical Physics and the Associate Chair of Equity and Wellness within the Department of Radiation Oncology at Michigan Medicine, Ann Arbor, Michigan
| | - Abigail J Stewart
- A.J. Stewart is the Sandra Schwartz Tangri Distinguished University Professor of Psychology and Women's and Gender Studies at the University of Michigan, Ann Arbor, Michigan
| | - Eva L Feldman
- E.L. Feldman is the James W. Albers Distinguished University Professor, Russell N. DeJong Professor of Neurology and the Director of the ALS Center for Excellence and the Director of the NeuroNetwork for Emerging Therapies at the University of Michigan, Ann Arbor, Michigan
| | - Isis H Settles
- I.H. Settles is a Professor of Psychology at the University of Michigan, Ann Arbor, Michigan
| | - Eve A Kerr
- E.A. Kerr is the Kutsche Memorial Chair of Internal Medicine at the University of Michigan Medical School, Chief of the General Medicine Division at the University of Michigan, Research Scientist at the VA Ann Arbor Healthcare System, Center for Clinical Management Research, Ann Arbor, Michigan
| | - Peter A Ubel
- P.A. Ubel is the Madge and Dennis T. McLawhorn University Professor of Business, Public Policy and Medicine at Duke University, Durham, North Carolina
| | - Nancy D Spector
- N.D. Spector is Professor of Pediatrics, Executive Director of Executive Leadership in Academic Medicine (ELAM) and Executive Leadership in Health Care (ELH), Senior Vice Dean for Faculty, and the Executive Director of the Lynn Yeakel Institute for Women's Health and Leadership at Drexel University, College of Medicine, Philadelphia, Pennsylvania
| | - Reshma Jagsi
- R. Jagsi is Lawrence W. Davis Professor and Chair of the Department of Radiation Oncology at Emory University School of Medicine, Atlanta, Georgia
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Kim K, Varghese M, Sun H, Abrishami S, Bowers E, Bridges D, Meijer JL, Singer K, Gregg B. The Influence of Maternal High Fat Diet During Lactation on Offspring Hematopoietic Priming. Endocrinology 2023; 165:bqad182. [PMID: 38048597 PMCID: PMC11032250 DOI: 10.1210/endocr/bqad182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/06/2023] [Revised: 11/28/2023] [Accepted: 11/29/2023] [Indexed: 12/06/2023]
Abstract
Obesity and metabolic diseases are rising among women of reproductive age, increasing offspring metabolic risk. Maternal nutritional interventions during lactation present an opportunity to modify offspring outcomes. We previously demonstrated in mice that adult male offspring have metabolic impairments and increased adipose tissue macrophages (ATM) when dams are fed high fat diet (HFD) during the postnatal lactation window (HFD PN). We sought to understand the effect of HFD during lactation on early-life inflammation. HFD PN offspring were evaluated at postnatal day 16 to 19 for tissue weight and gene expression. Profiling of adipose tissue and bone marrow immune cells was conducted through lipidomics, in vitro myeloid colony forming unit assays, and flow cytometry. HFD PN mice had more visceral gonadal white adipose tissue (GWAT) and subcutaneous fat. Adipose tissue RNA sequencing demonstrated enrichment of inflammation, chemotaxis, and fatty acid metabolism and concordant changes in GWAT lipidomics. Bone marrow (BM) of both HFD PN male and female offspring had increased monocytes (CD45+Ly6G-CD11b+CD115+) and B cells (CD45+Ly6G-CD11b-CD19+). Similarly, serum from HFD PN offspring enhanced in vitro BM myeloid colonies in a toll-like receptor 4-dependent manner. We identified that male HFD PN offspring had increased GWAT pro-inflammatory CD11c+ ATMs (CD45+CD64+). Maternal exposure to HFD alters milk lipids enhancing adiposity and myeloid inflammation even in early life. Future studies are needed to understand the mechanisms driving this pro-inflammatory state of both BM and ATMs, the causes of the sexually dimorphic phenotypes, and the feasibility of intervening in this window to improve metabolic health.
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Affiliation(s)
- Katherine Kim
- Department of Pediatrics, Michigan Medicine, University of Michigan, Ann Arbor, MI 48109, USA
| | - Mita Varghese
- Department of Pediatrics, Michigan Medicine, University of Michigan, Ann Arbor, MI 48109, USA
| | - Haijing Sun
- Department of Pediatrics, Michigan Medicine, University of Michigan, Ann Arbor, MI 48109, USA
| | - Simin Abrishami
- Department of Pediatrics, Michigan Medicine, University of Michigan, Ann Arbor, MI 48109, USA
| | - Emily Bowers
- Department of Pediatrics, Michigan Medicine, University of Michigan, Ann Arbor, MI 48109, USA
| | - Dave Bridges
- Department of Nutritional Sciences, University of Michigan School of Public Health, Ann Arbor, MI 48109, USA
| | - Jennifer L Meijer
- Department of Medicine, Dartmouth-Hitchcock Medical Center, Lebanon, NH 03756, USA
- Geisel School of Medicine, Dartmouth College, Hanover, NH 03755, USA
| | - Kanakadurga Singer
- Department of Pediatrics, Michigan Medicine, University of Michigan, Ann Arbor, MI 48109, USA
| | - Brigid Gregg
- Department of Pediatrics, Michigan Medicine, University of Michigan, Ann Arbor, MI 48109, USA
- Department of Nutritional Sciences, University of Michigan School of Public Health, Ann Arbor, MI 48109, USA
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Kumar AJ, Parthasarathy C, Prescott HC, Denstaedt SJ, Newstead MW, Bridges D, Bustamante A, Singer K, Singer BH. Pneumosepsis survival in the setting of obesity leads to persistent steatohepatitis and metabolic dysfunction. Hepatol Commun 2023; 7:e0210. [PMID: 37556193 PMCID: PMC10412436 DOI: 10.1097/hc9.0000000000000210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Accepted: 05/19/2023] [Indexed: 08/10/2023] Open
Abstract
BACKGROUND As critical care practice evolves, the sepsis survivor population continues to expand, often with lingering inflammation in many organs, including the liver. Given the concurrently increasing population of patients with NAFLD, in this study, we aimed to understand the long-term effect of sepsis on pre-existing NAFLD and hyperglycemia. METHODS Male mice were randomized to a high-fat diet or a control diet (CD). After 24 weeks on diet, mice were inoculated with Klebsiella pneumoniae (Kpa). Serial glucose tolerance tests, and insulin and pyruvate challenge tests were performed 1 week before infection and at 2 and 6 weeks after infection. Whole tissue RNA sequencing and histological evaluation of the liver were performed. To test whether persistent inflammation could be reproduced in other abnormal liver environments, mice were also challenged with Kpa after exposure to a methionine-choline-deficient high-fat diet. Finally, a retrospective cohort of 65,139 patients was analyzed to evaluate whether obesity was associated with liver injury after sepsis. RESULTS After Kpa inoculation, high-fat diet mice had normalized fasting blood glucose without a change in insulin sensitivity but with a notable decrease in pyruvate utilization. Liver examination revealed focal macrophage collections and a unique inflammatory gene signature on RNA analysis. In the clinical cohort, preobesity, and class 1 and class 2 obesity were associated with increased odds of elevated aminotransferase levels 1-2 years after sepsis. CONCLUSIONS The combination of diet-induced obesity and pneumosepsis survival in a murine model resulted in unique changes in gluconeogenesis and liver inflammation, consistent with the progression of benign steatosis to steatohepatitis. In a cohort study, obese patients had an increased risk of elevated aminotransferase levels 1-2 years following sepsis.
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Affiliation(s)
- Avnee J. Kumar
- Department of Internal Medicine, Division of Pulmonary and Critical Care, University of Michigan School of Medicine, Ann Arbor, Michigan, USA
| | - Chitra Parthasarathy
- Department of Internal Medicine, Division of Pulmonary and Critical Care, University of Michigan School of Medicine, Ann Arbor, Michigan, USA
| | - Hallie C. Prescott
- Department of Internal Medicine, Division of Pulmonary and Critical Care, University of Michigan School of Medicine, Ann Arbor, Michigan, USA
- VA Center for Clinical Management Research, Ann Arbor, Michigan, USA
| | - Scott J. Denstaedt
- Department of Internal Medicine, Division of Pulmonary and Critical Care, University of Michigan School of Medicine, Ann Arbor, Michigan, USA
| | - Michael W. Newstead
- Department of Internal Medicine, Division of Pulmonary and Critical Care, University of Michigan School of Medicine, Ann Arbor, Michigan, USA
| | - Dave Bridges
- Department of Nutritional Sciences, University of Michigan School of Public Health, Ann Arbor, Michigan, USA
| | - Angela Bustamante
- Department of Internal Medicine, Division of Pulmonary and Critical Care, University of Michigan School of Medicine, Ann Arbor, Michigan, USA
| | - Kanakadurga Singer
- Department of Pediatrics, Division of Endocrinology, University of Michigan School of Medicine, Ann Arbor, Michigan, USA
| | - Benjamin H. Singer
- Department of Internal Medicine, Division of Pulmonary and Critical Care, University of Michigan School of Medicine, Ann Arbor, Michigan, USA
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Jagsi R, Griffith K, Krenz C, Jones RD, Cutter C, Feldman EL, Jacobson C, Kerr E, Paradis K, Singer K, Spector N, Stewart A, Telem D, Ubel P, Settles I. Workplace Harassment, Cyber Incivility, and Climate in Academic Medicine. JAMA 2023; 329:1848-1858. [PMID: 37278814 PMCID: PMC10245188 DOI: 10.1001/jama.2023.7232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Accepted: 04/13/2023] [Indexed: 06/07/2023]
Abstract
Importance The culture of academic medicine may foster mistreatment that disproportionately affects individuals who have been marginalized within a given society (minoritized groups) and compromises workforce vitality. Existing research has been limited by a lack of comprehensive, validated measures, low response rates, and narrow samples as well as comparisons limited to the binary gender categories of male or female assigned at birth (cisgender). Objective To evaluate academic medical culture, faculty mental health, and their relationship. Design, Setting, and Participants A total of 830 faculty members in the US received National Institutes of Health career development awards from 2006-2009, remained in academia, and responded to a 2021 survey that had a response rate of 64%. Experiences were compared by gender, race and ethnicity (using the categories of Asian, underrepresented in medicine [defined as race and ethnicity other than Asian or non-Hispanic White], and White), and lesbian, gay, bisexual, transgender, queer (LGBTQ+) status. Multivariable models were used to explore associations between experiences of culture (climate, sexual harassment, and cyber incivility) with mental health. Exposures Minoritized identity based on gender, race and ethnicity, and LGBTQ+ status. Main Outcomes and Measures Three aspects of culture were measured as the primary outcomes: organizational climate, sexual harassment, and cyber incivility using previously developed instruments. The 5-item Mental Health Inventory (scored from 0 to 100 points with higher values indicating better mental health) was used to evaluate the secondary outcome of mental health. Results Of the 830 faculty members, there were 422 men, 385 women, 2 in nonbinary gender category, and 21 who did not identify gender; there were 169 Asian respondents, 66 respondents underrepresented in medicine, 572 White respondents, and 23 respondents who did not report their race and ethnicity; and there were 774 respondents who identified as cisgender and heterosexual, 31 as having LGBTQ+ status, and 25 who did not identify status. Women rated general climate (5-point scale) more negatively than men (mean, 3.68 [95% CI, 3.59-3.77] vs 3.96 [95% CI, 3.88-4.04], respectively, P < .001). Diversity climate ratings differed significantly by gender (mean, 3.72 [95% CI, 3.64-3.80] for women vs 4.16 [95% CI, 4.09-4.23] for men, P < .001) and by race and ethnicity (mean, 4.0 [95% CI, 3.88-4.12] for Asian respondents, 3.71 [95% CI, 3.50-3.92] for respondents underrepresented in medicine, and 3.96 [95% CI, 3.90-4.02] for White respondents, P = .04). Women were more likely than men to report experiencing gender harassment (sexist remarks and crude behaviors) (71.9% [95% CI, 67.1%-76.4%] vs 44.9% [95% CI, 40.1%-49.8%], respectively, P < .001). Respondents with LGBTQ+ status were more likely to report experiencing sexual harassment than cisgender and heterosexual respondents when using social media professionally (13.3% [95% CI, 1.7%-40.5%] vs 2.5% [95% CI, 1.2%-4.6%], respectively, P = .01). Each of the 3 aspects of culture and gender were significantly associated with the secondary outcome of mental health in the multivariable analysis. Conclusions and Relevance High rates of sexual harassment, cyber incivility, and negative organizational climate exist in academic medicine, disproportionately affecting minoritized groups and affecting mental health. Ongoing efforts to transform culture are necessary.
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Affiliation(s)
- Reshma Jagsi
- Medical School, University of Michigan, Ann Arbor
- Emory University, Atlanta, Georgia
| | | | - Chris Krenz
- Medical School, University of Michigan, Ann Arbor
| | | | | | | | | | - Eve Kerr
- Medical School, University of Michigan, Ann Arbor
| | | | | | - Nancy Spector
- College of Medicine, Drexel University, Philadelphia, Pennsylvania
| | - Abby Stewart
- Department of Psychology, University of Michigan, Ann Arbor, Michigan
| | - Dana Telem
- Medical School, University of Michigan, Ann Arbor
| | - Peter Ubel
- School of Medicine, Duke University, Durham, North Carolina
| | - Isis Settles
- Department of Psychology, University of Michigan, Ann Arbor, Michigan
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Song J, Farris D, Ariza P, Moorjani S, Varghese M, Blin M, Chen J, Tyrrell D, Zhang M, Singer K, Salmon M, Goldstein DR. Age-associated adipose tissue inflammation promotes monocyte chemotaxis and enhances atherosclerosis. Aging Cell 2023; 22:e13783. [PMID: 36683460 PMCID: PMC9924943 DOI: 10.1111/acel.13783] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2022] [Revised: 10/31/2022] [Accepted: 01/05/2023] [Indexed: 01/24/2023] Open
Abstract
Although aging enhances atherosclerosis, we do not know if this occurs via alterations in circulating immune cells, lipid metabolism, vasculature, or adipose tissue. Here, we examined whether aging exerts a direct pro-atherogenic effect on adipose tissue in mice. After demonstrating that aging augmented the inflammatory profile of visceral but not subcutaneous adipose tissue, we transplanted visceral fat from young or aged mice onto the right carotid artery of Ldlr-/- recipients. Aged fat transplants not only increased atherosclerotic plaque size with increased macrophage numbers in the adjacent carotid artery, but also in distal vascular territories, indicating that aging of the adipose tissue enhances atherosclerosis via secreted factors. By depleting macrophages from the visceral fat, we identified that adipose tissue macrophages are major contributors of the secreted factors. To identify these inflammatory factors, we found that aged fat transplants secreted increased levels of the inflammatory mediators TNFα, CXCL2, and CCL2, which synergized to promote monocyte chemotaxis. Importantly, the combined blockade of these inflammatory mediators impeded the ability of aged fat transplants to enhance atherosclerosis. In conclusion, our study reveals that aging enhances atherosclerosis via increased inflammation of visceral fat. Our study suggests that future therapies targeting the visceral fat may reduce atherosclerosis disease burden in the expanding older population.
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Affiliation(s)
- Jianrui Song
- Department of Internal Medicine, Division of Cardiovascular MedicineUniversity of MichiganAnn ArborMichiganUSA
| | - Diana Farris
- Department of Internal Medicine, Division of Cardiovascular MedicineUniversity of MichiganAnn ArborMichiganUSA
| | - Paola Ariza
- Department of Internal Medicine, Division of Cardiovascular MedicineUniversity of MichiganAnn ArborMichiganUSA
| | - Smriti Moorjani
- Department of Internal Medicine, Division of Cardiovascular MedicineUniversity of MichiganAnn ArborMichiganUSA
| | - Mita Varghese
- Department of Pediatrics, Division of EndocrinologyUniversity of MichiganAnn ArborMichiganUSA
| | - Muriel Blin
- Department of Internal Medicine, Division of Cardiovascular MedicineUniversity of MichiganAnn ArborMichiganUSA
| | - Judy Chen
- Department of Internal Medicine, Division of Cardiovascular MedicineUniversity of MichiganAnn ArborMichiganUSA
- Graduate Program in ImmunologyUniversity of MichiganAnn ArborMichiganUSA
| | - Daniel Tyrrell
- Department of Internal Medicine, Division of Cardiovascular MedicineUniversity of MichiganAnn ArborMichiganUSA
| | - Min Zhang
- Department of BiostatisticsUniversity of MichiganAnn ArborMichiganUSA
| | - Kanakadurga Singer
- Department of Pediatrics, Division of EndocrinologyUniversity of MichiganAnn ArborMichiganUSA
- Graduate Program in ImmunologyUniversity of MichiganAnn ArborMichiganUSA
| | - Morgan Salmon
- Department of Cardiac SurgeryUniversity of MichiganAnn ArborMichiganUSA
| | - Daniel R. Goldstein
- Department of Internal Medicine, Division of Cardiovascular MedicineUniversity of MichiganAnn ArborMichiganUSA
- Graduate Program in ImmunologyUniversity of MichiganAnn ArborMichiganUSA
- Department of Microbiology and ImmunologyUniversity of MichiganAnn ArborMichiganUSA
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Jagsi R, Beeland TD, Sia K, Szczygiel LA, Allen MR, Arora VM, Bair-Merritt M, Bauman MD, Bogner HR, Daumit G, Davis E, Fagerlin A, Ford DE, Gbadegesin R, Griendling K, Hartmann K, Hedayati SS, Jackson RD, Matulevicius S, Mugavero MJ, Nehl EJ, Neogi T, Regensteiner JG, Rubin MA, Rubio D, Singer K, Tucker Edmonds B, Volerman A, Laney S, Patton C, Escobar Alvarez S. Doris Duke Charitable Foundation Fund to Retain Clinical Scientists: innovating support for early-career family caregivers. J Clin Invest 2022; 132:166075. [PMID: 36453546 PMCID: PMC9711869 DOI: 10.1172/jci166075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Affiliation(s)
| | | | - Kevin Sia
- Doris Duke Charitable Foundation, New York, New York, USA
| | | | - Matthew R. Allen
- Indiana University School of Medicine, Indianapolis, Indiana, USA
| | - Vineet M. Arora
- University of Chicago Pritzker School of Medicine, Chicago, Illinois, USA
| | | | | | - Hillary R. Bogner
- University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania, USA
| | - Gail Daumit
- Johns Hopkins School of Medicine, Baltimore, Maryland, USA
| | - Esa Davis
- University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Angela Fagerlin
- University of Utah Spencer Fox Eccles School of Medicine, Salt Lake City, Utah, USA
| | - Daniel E. Ford
- Johns Hopkins School of Medicine, Baltimore, Maryland, USA
| | | | | | | | | | | | | | | | | | - Tuhina Neogi
- Boston University School of Medicine, Boston, Massachusetts, USA
| | | | - Michael A. Rubin
- University of Utah Spencer Fox Eccles School of Medicine, Salt Lake City, Utah, USA
| | - Doris Rubio
- University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | | | | | - Anna Volerman
- University of Chicago Pritzker School of Medicine, Chicago, Illinois, USA
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8
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Li Z, Bagchi DP, Zhu J, Bowers E, Yu H, Hardij J, Mori H, Granger K, Skjaerlund J, Mandair G, Abrishami S, Singer K, Hankenson KD, Rosen CJ, MacDougald OA. Constitutive bone marrow adipocytes suppress local bone formation. JCI Insight 2022; 7:160915. [PMID: 36048537 PMCID: PMC9675472 DOI: 10.1172/jci.insight.160915] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Accepted: 08/31/2022] [Indexed: 12/15/2022] Open
Abstract
BM adipocytes (BMAd) are a unique cell population derived from BM mesenchymal progenitors and marrow adipogenic lineage precursors. Although they have long been considered to be a space filler within bone cavities, recent studies have revealed important physiological roles in hematopoiesis and bone metabolism. To date, the approaches used to study BMAd function have been confounded by contributions by nonmarrow adipocytes or by BM stromal cells. To address this gap in the field, we have developed a BMAd-specific Cre mouse model to deplete BMAds by expression of diphtheria toxin A (DTA) or by deletion of peroxisome proliferator-activated receptor gamma (Pparg). We found that DTA-induced loss of BMAds results in decreased hematopoietic stem and progenitor cell numbers and increased bone mass in BMAd-enriched locations, including the distal tibiae and caudal vertebrae. Elevated bone mass appears to be secondary to enhanced endosteal bone formation, suggesting a local effect caused by depletion of BMAd. Augmented bone formation with BMAd depletion protects mice from bone loss induced by caloric restriction or ovariectomy, and it facilitates the bone-healing process after fracture. Finally, ablation of Pparg also reduces BMAd numbers and largely recapitulates high-bone mass phenotypes observed with DTA-induced BMAd depletion.
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Affiliation(s)
- Ziru Li
- Department of Molecular & Integrative Physiology and
| | | | - Junxiong Zhu
- Department of Orthopedic Surgery, University of Michigan Medical School, Ann Arbor, Michigan, USA
- Department of Orthopedic Surgery, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Emily Bowers
- Department of Pediatrics, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Hui Yu
- Department of Molecular & Integrative Physiology and
| | - Julie Hardij
- Department of Molecular & Integrative Physiology and
| | - Hiroyuki Mori
- Department of Molecular & Integrative Physiology and
| | | | - Jon Skjaerlund
- Department of Orthopedic Surgery, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Gurjit Mandair
- Department of Biologic and Materials Sciences, School of Dentistry, University of Michigan, Ann Arbor, Michigan, USA
| | - Simin Abrishami
- Department of Pediatrics, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Kanakadurga Singer
- Department of Molecular & Integrative Physiology and
- Department of Pediatrics, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Kurt D. Hankenson
- Department of Orthopedic Surgery, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | | | - Ormond A. MacDougald
- Department of Molecular & Integrative Physiology and
- Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, Michigan, USA
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9
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Li Z, Bowers E, Zhu J, Yu H, Hardij J, Bagchi DP, Mori H, Lewis KT, Granger K, Schill RL, Romanelli SM, Abrishami S, Hankenson KD, Singer K, Rosen CJ, MacDougald OA. Lipolysis of bone marrow adipocytes is required to fuel bone and the marrow niche during energy deficits. eLife 2022; 11:e78496. [PMID: 35731039 PMCID: PMC9273217 DOI: 10.7554/elife.78496] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Accepted: 06/21/2022] [Indexed: 11/13/2022] Open
Abstract
To investigate roles for bone marrow adipocyte (BMAd) lipolysis in bone homeostasis, we created a BMAd-specific Cre mouse model in which we knocked out adipose triglyceride lipase (ATGL, Pnpla2 gene). BMAd-Pnpla2-/- mice have impaired BMAd lipolysis, and increased size and number of BMAds at baseline. Although energy from BMAd lipid stores is largely dispensable when mice are fed ad libitum, BMAd lipolysis is necessary to maintain myelopoiesis and bone mass under caloric restriction. BMAd-specific Pnpla2 deficiency compounds the effects of caloric restriction on loss of trabecular bone in male mice, likely due to impaired osteoblast expression of collagen genes and reduced osteoid synthesis. RNA sequencing analysis of bone marrow adipose tissue reveals that caloric restriction induces dramatic elevations in extracellular matrix organization and skeletal development genes, and energy from BMAd is required for these adaptations. BMAd-derived energy supply is also required for bone regeneration upon injury, and maintenance of bone mass with cold exposure.
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Affiliation(s)
- Ziru Li
- University of Michigan Medical School, Department of Molecular & Integrative PhysiologyAnn ArborUnited States
| | - Emily Bowers
- University of Michigan Medical School, Department of PediatricsAnn ArborUnited States
| | - Junxiong Zhu
- Department of Orthopedic Surgery, University of Michigan Medical SchoolAnn ArborUnited States
- Department of Orthopedic Surgery, The Second Affiliated Hospital, Zhejiang University School of MedicineHangzhouChina
| | - Hui Yu
- University of Michigan Medical School, Department of Molecular & Integrative PhysiologyAnn ArborUnited States
| | - Julie Hardij
- University of Michigan Medical School, Department of Molecular & Integrative PhysiologyAnn ArborUnited States
| | - Devika P Bagchi
- University of Michigan Medical School, Department of Molecular & Integrative PhysiologyAnn ArborUnited States
| | - Hiroyuki Mori
- University of Michigan Medical School, Department of Molecular & Integrative PhysiologyAnn ArborUnited States
| | - Kenneth T Lewis
- University of Michigan Medical School, Department of Molecular & Integrative PhysiologyAnn ArborUnited States
| | - Katrina Granger
- University of Michigan Medical School, Department of Molecular & Integrative PhysiologyAnn ArborUnited States
| | - Rebecca L Schill
- University of Michigan Medical School, Department of Molecular & Integrative PhysiologyAnn ArborUnited States
| | - Steven M Romanelli
- University of Michigan Medical School, Department of Molecular & Integrative PhysiologyAnn ArborUnited States
| | - Simin Abrishami
- University of Michigan Medical School, Department of PediatricsAnn ArborUnited States
| | - Kurt D Hankenson
- Department of Orthopedic Surgery, University of Michigan Medical SchoolAnn ArborUnited States
| | - Kanakadurga Singer
- University of Michigan Medical School, Department of Molecular & Integrative PhysiologyAnn ArborUnited States
- University of Michigan Medical School, Department of PediatricsAnn ArborUnited States
| | | | - Ormond A MacDougald
- University of Michigan Medical School, Department of Molecular & Integrative PhysiologyAnn ArborUnited States
- University of Michigan Medical School, Department of Internal MedicineAnn ArborUnited States
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10
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Huizinga GP, Warheit-Niemi HI, Gallagher K, Moore BB, Singer K. Obesity Inhibits Innate Immune Functions During Pseudomonas aeruginosa Pneumonia. The Journal of Immunology 2022. [DOI: 10.4049/jimmunol.208.supp.50.11] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Abstract
Obesity is a major global public health concern. Worldwide, 39% of the population is overweight and 13% of the population is obese. Obesity contributes to many diseases, such as heart disease, stroke, some cancers, and notably, type 2 diabetes (T2D). Although T2D itself is a non-communicable disease, many patients with diabetes are more susceptible to microbial infections and exhibit a higher burden of disease. Although obese animals have an increased production of myeloid cells, previous work from our labs has shown that a failure to heal diabetic wounds corresponds to elevated levels of prostaglandin E2 (PGE2) in the inflammatory macrophages that are recruited to the wound. Furthermore, past studies from our lab have demonstrated that PGE2 signaling can impair the innate immune functions of macrophages. Therefore, we hypothesized that diabetic obese mice would be more susceptible to a respiratory Pseudomonas aeruginosa strain PA01 infection due to impaired function of lung resident and recruited macrophages. Preliminary studies demonstrate that obese diabetic mice do have an increased P. aeruginosa burden in the lung 24 hours after infection. Additionally, we have determined that naïve obese diabetic mice have an increase in lung neutrophils compared to lean mice, however, after infection with P. aeruginosa, these mice have a trend of decreased neutrophil recruitment. Additionally, functional assays show that macrophages and neutrophils from obese diabetic mice have a defect in killing P. aeruginosa. These observations suggest that obese diabetic mice have not only a defect in innate immune cell recruitment, but also a defect in innate immune cell function during bacterial pneumonia.
Supported by grants from NIH (T32 AI007528-21)
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11
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Lee H, Burrows HL, Singer K, Brower KJ, Bradford CR, Spencley B, Owens L, Morgan HK. Operational Constraints and Gender Biases: A Qualitative Analysis of Physician Parenting Experiences. Womens Health Rep (New Rochelle) 2022; 3:297-306. [PMID: 35415712 PMCID: PMC8994438 DOI: 10.1089/whr.2021.0099] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Accepted: 02/05/2022] [Indexed: 06/14/2023]
Abstract
OBJECTIVE Although parenting responsibilities are correlated with gender disparities in professional development and salary, the nature of parental challenges is not well characterized. The aims of this study were to (1) illuminate faculty physicians' experiences with parenting and (2) identify system challenges and opportunities for improvement. MATERIALS AND METHODS In October 2019, a survey about parenting was sent to all physician faculty at a large Midwest academic medical center. Qualitative analysis of free-text response to the survey item "is there anything you wish to share about your experience of pregnancy or parenting as a physician" was performed. Themes were inductively identified and developed from the responses in a team-based iterative approach. RESULTS Of 2069 total physician faculty, 1085 (52.4%) responded to the survey and 253 (23%) of the respondents provided free-text comments. From these comments, the authors identified three themes as sources of challenges for physician parents: operational constraints, gender biases, and nontraditional or nonheteronormative family structures. Operational factors pertained to lack of scheduling flexibility, childcare challenges, lactation, colleague coverage, and transparency of policies. Responses indicated that gender biases are encountered by all genders, and expectations built on assumptions of "traditional" gender roles and family structure are problematic for many physician parents. CONCLUSION Addressing the challenges and opportunities identified in the study is critical to building a more supportive institutional culture around parenting and to increase gender parity in academic medicine.
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Affiliation(s)
- Hsin Lee
- Department of Obstetrics and Gynecology, University of Michigan, Ann Arbor, Michigan, USA
| | - Heather L. Burrows
- Department of Pediatrics, University of Michigan, Ann Arbor, Michigan, USA
| | - Kanakadurga Singer
- Department of Pediatrics, University of Michigan, Ann Arbor, Michigan, USA
| | - Kirk J. Brower
- Department of Psychiatry, University of Michigan, Ann Arbor, Michigan, USA
| | - Carol R. Bradford
- Department of Otolaryngology-Head and Neck Surgery, University of Michigan, Ann Arbor, Michigan, USA
| | - Brooke Spencley
- Obstetrics and Gynecology, University of Wisconsin, Madison, Wisconsin, USA
| | - Lauren Owens
- Department of Obstetrics and Gynecology, University of Michigan, Ann Arbor, Michigan, USA
| | - Helen Kang Morgan
- Department of Obstetrics and Gynecology, University of Michigan, Ann Arbor, Michigan, USA
- Department of Learning Health Sciences, University of Michigan, Ann Arbor, Michigan, USA
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12
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Mancuso P, Curtis JL, Weitzel AM, Griffin CA, Bouchard B, Freeman CM, Bridges D, Singer K. Diet-induced obesity in mice impairs host defense against Klebsiella pneumonia in vivo and glucose transport and bactericidal functions in neutrophils in vitro. Am J Physiol Lung Cell Mol Physiol 2022; 322:L116-L128. [PMID: 34850640 PMCID: PMC8794018 DOI: 10.1152/ajplung.00008.2021] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Revised: 11/16/2021] [Accepted: 11/16/2021] [Indexed: 01/03/2023] Open
Abstract
Obesity impairs host defense against Klebsiella pneumoniae, but responsible mechanisms are incompletely understood. To determine the impact of diet-induced obesity on pulmonary host defense against K. pneumoniae, we fed 6-wk-old male C57BL/6j mice a normal diet (ND) or high-fat diet (HFD) (13% vs. 60% fat, respectively) for 16 wk. Mice were intratracheally infected with Klebsiella, assayed at 24 or 48 h for bacterial colony-forming units, lung cytokines, and leukocytes from alveolar spaces, lung parenchyma, and gonadal adipose tissue were assessed using flow cytometry. Neutrophils from uninfected mice were cultured with and without 2-deoxy-d-glucose (2-DG) and assessed for phagocytosis, killing, reactive oxygen intermediates (ROI), transport of 2-DG, and glucose transporter (GLUT1-4) transcripts, and protein expression of GLUT1 and GLUT3. HFD mice had higher lung and splenic bacterial burdens. In HFD mice, baseline lung homogenate concentrations of IL-1β, IL-6, IL-17, IFN-γ, CXCL2, and TNF-α were reduced relative to ND mice, but following infection were greater for IL-6, CCL2, CXCL2, and IL-1β (24 h only). Despite equivalent lung homogenate leukocytes, HFD mice had fewer intraalveolar neutrophils. HFD neutrophils exhibited decreased Klebsiella phagocytosis and killing and reduced ROI to heat-killed Klebsiella in vitro. 2-DG transport was lower in HFD neutrophils, with reduced GLUT1 and GLUT3 transcripts and protein (GLUT3 only). Blocking glycolysis with 2-DG impaired bacterial killing and ROI production in neutrophils from mice fed ND but not HFD. Diet-induced obesity impairs pulmonary Klebsiella clearance and augments blood dissemination by reducing neutrophil killing and ROI due to impaired glucose transport.
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Affiliation(s)
- Peter Mancuso
- Department of Nutritional Sciences, School of Public Health, University of Michigan, Ann Arbor, Michigan
- Graduate Program in Immunology, University of Michigan, Ann Arbor, Michigan
| | - Jeffrey L Curtis
- Graduate Program in Immunology, University of Michigan, Ann Arbor, Michigan
- Division of Pulmonary & Critical Care Medicine, Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan
- Medical Service, Veterans Affairs Ann Arbor Healthcare System, Ann Arbor, Michigan
| | - Anne M Weitzel
- Department of Nutritional Sciences, School of Public Health, University of Michigan, Ann Arbor, Michigan
| | - Cameron A Griffin
- Division of Pediatric Endocrinology, Department of Pediatrics, University of Michigan, Ann Arbor, Michigan
| | - Benjamin Bouchard
- Department of Nutritional Sciences, School of Public Health, University of Michigan, Ann Arbor, Michigan
| | - Christine M Freeman
- Graduate Program in Immunology, University of Michigan, Ann Arbor, Michigan
- Division of Pulmonary & Critical Care Medicine, Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan
- Research Service, Veterans Affairs Ann Arbor Healthcare System, Ann Arbor, Michigan
| | - Dave Bridges
- Department of Nutritional Sciences, School of Public Health, University of Michigan, Ann Arbor, Michigan
| | - Kanakadurga Singer
- Graduate Program in Immunology, University of Michigan, Ann Arbor, Michigan
- Division of Pediatric Endocrinology, Department of Pediatrics, University of Michigan, Ann Arbor, Michigan
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13
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Varghese M, Clemente J, Lerner A, Abrishami S, Islam M, Subbaiah P, Singer K. Monocyte Trafficking and Polarization Contribute to Sex Differences in Meta-Inflammation. Front Endocrinol (Lausanne) 2022; 13:826320. [PMID: 35422759 PMCID: PMC9001155 DOI: 10.3389/fendo.2022.826320] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 02/24/2022] [Indexed: 11/13/2022] Open
Abstract
Obesity is associated with systemic inflammation and immune cell recruitment to metabolic tissues. Sex differences have been observed where male mice challenged with high fat diet (HFD) exhibit greater adipose tissue inflammation than females demonstrating a role for sex hormones in differential inflammatory responses. Circulating monocytes that respond to dietary lipids and chemokines and produce cytokines are the primary source of recruited adipose tissue macrophages (ATMs). In this study, we investigated sexual dimorphism in biological pathways in HFD-fed ATMs from male and female mice by RNA-seq. We also conducted chemotaxis assays to investigate sex differences in the migration of monocytes isolated from bone marrow from male and female mice toward a dietary saturated lipid - palmitate (PA), and a chemokine - monocyte chemoattractant protein 1 (MCP1), factors known to stimulate myeloid cells in obesity. ATM RNA-Seq demonstrated sex differences of both metabolic and inflammatory activation, including pathways for chemokine signaling and leukocyte trans-endothelial migration. In vivo monocyte transfer studies demonstrated that male monocytes traffic to female adipose tissue to generate ATMs more readily. In chemotaxis assays, lean male monocytes migrated in greater numbers than females toward PA and MCP1. With short-term HFD, male and female monocytes migrated similarly, but in chronic HFD, male monocytes showed greater migration than females upon PA and MCP1 stimulation. Studies with monocytes from toll-like receptor 4 knockout mice (Tlr4-/- ) demonstrated that both males and females showed decreased migration than WT in response to PA and MCP1 implying a role for TLR4 in monocyte influx in response to meta-inflammation. Overall, these data demonstrate the role of sexual dimorphism in monocyte recruitment and response to metabolic stimuli that may influence meta-inflammation in obesity.
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Affiliation(s)
- Mita Varghese
- Department of Pediatrics, Michigan Medicine, University of Michigan, Ann Arbor, MI, United States
| | - Jeremy Clemente
- Department of Pediatrics, Michigan Medicine, University of Michigan, Ann Arbor, MI, United States
| | - Arianna Lerner
- Department of Pediatrics, Michigan Medicine, University of Michigan, Ann Arbor, MI, United States
| | - Simin Abrishami
- Department of Pediatrics, Michigan Medicine, University of Michigan, Ann Arbor, MI, United States
| | - Mohammed Islam
- Department of Pediatrics, Michigan Medicine, University of Michigan, Ann Arbor, MI, United States
| | - Perla Subbaiah
- Department of Statistics and Mathematics, Oakland University, Rochester, MI, United States
| | - Kanakadurga Singer
- Department of Pediatrics, Michigan Medicine, University of Michigan, Ann Arbor, MI, United States
- *Correspondence: Kanakadurga Singer,
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14
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Varghese M, Griffin C, Abrishami S, Eter L, Lanzetta N, Hak L, Clemente J, Agarwal D, Lerner A, Westerhoff M, Patel R, Bowers E, Islam M, Subbaiah P, Singer K. Sex hormones regulate metainflammation in diet-induced obesity in mice. J Biol Chem 2021; 297:101229. [PMID: 34599964 PMCID: PMC8526779 DOI: 10.1016/j.jbc.2021.101229] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Revised: 09/13/2021] [Accepted: 09/21/2021] [Indexed: 12/11/2022] Open
Abstract
Men have a statistically higher risk of metabolic and cardiovascular disease than premenopausal women, but the mechanisms mediating these differences are elusive. Chronic inflammation during obesity contributes to disease risk and is significantly more robust in males. Prior work demonstrated that compared with obese males, obese females have reduced proinflammatory adipose tissue macrophages (ATMs). Given the paucity of data on how sex hormones contribute to macrophage responses in obesity, we sought to understand the role of sex hormones in promoting obesity-induced myeloid inflammation. We used gonadectomy, estrogen receptor-deficient alpha chimeras, and androgen-insensitive mice to model sex hormone deficiency. These models were evaluated in diet-induced obesity conditions (high-fat diet [HFD]) and in vitro myeloid assays. We found that ovariectomy increased weight gain and adiposity. Ovariectomized females had increased ATMs and bone marrow myeloid colonies compared with sham-gonadectomized females. In addition, castrated males exposed to HFD had improved glucose tolerance, insulin sensitivity, and adiposity with fewer Ly6chi monocytes and bone marrow myeloid colonies compared with sham-gonadectomized males, although local adipose inflammation was enhanced. Similar findings were observed in androgen-insensitive mice; however, these mice had fewer CD11c+ ATMs, implying a developmental role for androgens in myelopoiesis and adipose inflammation. We concluded that gonadectomy results in convergence of metabolic and inflammatory responses to HFD between the sexes, and that myeloid estrogen receptor alpha contributes minimally to diet-induced inflammatory responses, whereas loss of androgen-receptor signaling improves metabolic and inflammatory outcomes. These studies demonstrate that sex hormones play a critical role in sex differences in obesity, metabolic dysfunction, and myeloid inflammation.
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Affiliation(s)
- Mita Varghese
- Department of Pediatrics, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, USA
| | - Cameron Griffin
- Department of Pediatrics, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, USA
| | - Simin Abrishami
- Department of Pediatrics, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, USA
| | - Leila Eter
- Department of Pediatrics, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, USA
| | - Nicholas Lanzetta
- Department of Pediatrics, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, USA
| | - Layla Hak
- Department of Pediatrics, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, USA
| | - Jeremy Clemente
- Department of Pediatrics, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, USA
| | - Devyani Agarwal
- Department of Pediatrics, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, USA
| | - Arianna Lerner
- Department of Pediatrics, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, USA
| | - Maria Westerhoff
- Department of Pathology, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, USA
| | - Ravi Patel
- Department of Pediatrics, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, USA
| | - Emily Bowers
- Department of Pediatrics, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, USA
| | - Mohammed Islam
- Department of Pediatrics, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, USA
| | - Perla Subbaiah
- Department of Mathematics and Statistics, Oakland University, Rochester, Michigan, USA
| | - Kanakadurga Singer
- Department of Pediatrics, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, USA.
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15
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LaBarre JL, Singer K, Burant CF. Advantages of Studying the Metabolome in Response to Mixed-Macronutrient Challenges and Suggestions for Future Research Designs. J Nutr 2021; 151:2868-2881. [PMID: 34255076 PMCID: PMC8681069 DOI: 10.1093/jn/nxab223] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 04/26/2021] [Accepted: 06/15/2021] [Indexed: 12/22/2022] Open
Abstract
Evaluating the postprandial response to a dietary challenge containing all macronutrients-carbohydrates, lipids, and protein-may provide stronger insights of metabolic health than a fasted measurement. Metabolomic profiling deepens the understanding of the homeostatic and adaptive response to a dietary challenge by classifying multiple metabolic pathways and biomarkers. A total of 26 articles were identified that measure the human blood metabolome or lipidome response to a mixed-macronutrient challenge. Most studies were cross-sectional, exploring the baseline and postprandial response to the dietary challenge. Large variations in study designs were reported, including the macronutrient and caloric composition of the challenge and the delivery of the challenge as a liquid shake or a solid meal. Most studies utilized a targeted metabolomics platform, assessing only a particular metabolic pathway, however, several studies utilized global metabolomics and lipidomics assays demonstrating the expansive postprandial response of the metabolome. The postprandial response of individual amino acids was largely dependent on the amino acid composition of the test meal, with the exception of alanine and proline, 2 nonessential amino acids. Long-chain fatty acids and unsaturated long-chain acylcarnitines rapidly decreased in response to the dietary challenges, representing the switch from fat to carbohydrate oxidation. Studies were reviewed that assessed the metabolome response in the context of obesity and metabolic diseases, providing insight on how weight status and disease influence the ability to cope with a nutrient load and return to homeostasis. Results demonstrate that the flexibility to respond to a substrate load is influenced by obesity and metabolic disease and flexibility alterations will be evident in downstream metabolites of fat, carbohydrate, and protein metabolism. In response, we propose suggestions for standardization between studies with the potential of creating a study exploring the postprandial response to a multitude of challenges with a variety of macronutrients.
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Affiliation(s)
| | - Kanakadurga Singer
- Department of Pediatrics, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Charles F Burant
- Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, MI, USA
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16
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Hutch CR, Stelmak D, Kanke M, Koch-Laskowski K, Cummings B, Griffin C, Leix K, Sethupathy P, Singer K, Sandoval DA. Diet-dependent sex differences in the response to vertical sleeve gastrectomy. Am J Physiol Endocrinol Metab 2021; 321:E11-E23. [PMID: 33998293 PMCID: PMC8321822 DOI: 10.1152/ajpendo.00060.2021] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Revised: 05/10/2021] [Accepted: 05/11/2021] [Indexed: 12/14/2022]
Abstract
Nearly 80% of patients that receive bariatric surgery are women, yet mechanistic preclinical studies have focused on males. The goal of this study was to determine the metabolic impact of diet- and surgery-induced weight loss in males, females, and ovariectomized females. All mice were fed a 60% high-fat diet (HFD) before undergoing either vertical sleeve gastrectomy (VSG) or sham surgery. Mice either remained on an HFD or were switched to a standard chow diet postsurgically. When maintained on an HFD, males and females decreased fat mass and improved oral glucose tolerance after VSG. After dietary intervention, additional adiposity was lost in both surgical groups. Ovariectomized females showed a blunted decrease in fat mass on an HFD, but lost significant adiposity after dietary intervention. Energy expenditure was impacted by dietary and not surgical intervention across all groups. Males decreased hepatic triglyceride levels after VSG, which was further decreased after dietary intervention. Intact and ovariectomized females had a blunted decrease in hepatic triglycerides after VSG, but a significant decrease after dietary intervention. The more pronounced effect of VSG on hepatic lipids in males is strongly associated with changes in hepatic expression of genes and microRNAs previously linked to hepatic lipid regulation and systemic energy homeostasis. These data highlight the importance of postsurgical diet on metabolic outcomes across sexes. Furthermore, these data suggest the impact of VSG on hepatic triglycerides is diet-dependent in females and support the hypothesis that males and females achieve similar metabolic outcome, at least within the liver, via distinct mechanisms.NEW & NOTEWORTHY These data highlight the interaction of postsurgical diet after bariatric surgery on metabolic outcomes across sexes. These data suggest the impact of VSG on hepatic triglycerides is diet-dependent in females and support the hypothesis that males and females achieve similar metabolic outcome, at least within the liver, via distinct mechanisms.
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Affiliation(s)
- Chelsea R Hutch
- Department of Surgery, University of Michigan Medical School, Ann Arbor, Michigan
| | - Daria Stelmak
- Department of Surgery, University of Michigan Medical School, Ann Arbor, Michigan
| | - Matt Kanke
- Department of Biomedical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, New York
| | - Kieran Koch-Laskowski
- Department of Biomedical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, New York
| | - Bethany Cummings
- Department of Biomedical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, New York
| | - Cameron Griffin
- Department of Pediatrics, University of Michigan Medical School, Ann Arbor, Michigan
| | - Kyle Leix
- Department of Surgery, University of Michigan Medical School, Ann Arbor, Michigan
| | - Praveen Sethupathy
- Department of Biomedical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, New York
| | - Kanakadurga Singer
- Department of Pediatrics, University of Michigan Medical School, Ann Arbor, Michigan
| | - Darleen A Sandoval
- Department of Pediatrics, Section of Nutrition and Division of Endocrinology, Metabolism and Diabetes, University of Colorado Anschutz Medical Campus, Aurora, Colorado
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17
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Islam MR, Schultz KA, Varghese M, Abrishami SH, Villano JS, Singer K. Weight Gain, Glucose Tolerance, and the Gut Microbiome of Male C57BL/6J Mice Housed on Corncob or Paper Bedding and Fed Normal or High-Fat Diet. J Am Assoc Lab Anim Sci 2021; 60:407-421. [PMID: 34183093 DOI: 10.30802/aalas-jaalas-20-000139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Understanding how differences in animal husbandry practices affect the reproducibility of research results is critical. We sought to understand how different beddings might influence dietary obesity studies. We compared the effects of paper and corncob bedding on weight gain, metabolism, and gut microbiome (GM) of mice fed a high-fat diet (HFD) or a normal diet (ND) and evaluated effects on fecal and cecal microbiomes collected from these cohorts after euthanasia. Male C57BL/6J mice at 5 wk age were allowed to acclimate to the facility and the assigned bedding for one week before being placed on HFD or remaining on the ND for 12 wk. Fecal pellets and cecal samples were collected and frozen for batched 16S sequencing. Mice had similar body weight, visceral gonadal white adipose tissue (GWAT), subcutaneous inguinal white adipose tissue (IWAT), liver and spleen weights and metabolic changes regardless of the bedding type. Baseline microbiota differences were detected one week after bedding assignment. After 12 wk, the GM showed significant differences depending on both bedding and diet. The effects of the bedding were not significantly different between endpoint fecal and cecal GM, despite the inherent differences in microbiota in fecal and cecal samples. A correlation was detected between diet and the relative abundance of Bacteroidetes and Verrucomicrobia: Akkermansia. In conclusion, this study demonstrates the importance of considering bedding type when performing dietary experiments.
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Affiliation(s)
- Mohammed R Islam
- Department of Pediatrics, Michigan Medicine, University of Michigan, Ann Arbor, Michigan
| | - Kimberly A Schultz
- Unit of Laboratory Animal Medicine, University of Michigan, Ann Arbor, Michigan
| | - Mita Varghese
- Department of Pediatrics, Michigan Medicine, University of Michigan, Ann Arbor, Michigan
| | - Simin H Abrishami
- Department of Pediatrics, Michigan Medicine, University of Michigan, Ann Arbor, Michigan
| | - Jason S Villano
- Research Animal Resources, Department of Molecular and Comparative Pathobiology, Johns Hopkins University, Baltimore, Maryland
| | - Kanakadurga Singer
- Department of Pediatrics, Michigan Medicine, University of Michigan, Ann Arbor, Michigan;,
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18
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Allen DB, Aye T, Boney CM, Eugster EA, Misra M, Singer K, Stafford D, Witchel SF, Zeitler P. Sustaining the Pediatric Endocrinology Workforce: Recommendations from the Pediatric Endocrine Society Workforce Task Force. J Pediatr 2021; 233:4-7. [PMID: 33137317 DOI: 10.1016/j.jpeds.2020.10.063] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Indexed: 10/23/2022]
Affiliation(s)
- David B Allen
- Division of Pediatric Endocrinology and Diabetes, University of Wisconsin School of Medicine and Public Health, Madison, WI.
| | - Tandy Aye
- Division of Pediatric Endocrinology, Stanford University School of Medicine, Stanford, CA
| | - Charlotte M Boney
- Division of Pediatric Endocrinology, University of Massachusetts Medical School-Baystate, Springfield, MA
| | - Erica A Eugster
- Division of Pediatric Endocrinology, Riley Hospital for Children at IU Health, Indiana University School of Medicine, Indianapolis, IN
| | - Madhusmita Misra
- Division of Pediatric Endocrinology, Massachusetts General Hospital and Harvard Medical School, Boston, MA
| | - Kanakadurga Singer
- Division of Pediatric Endocrinology, Department of Pediatrics, University of Michigan, Ann Arbor, MI
| | - Diane Stafford
- Division of Pediatric Endocrinology, Stanford University School of Medicine, Stanford, CA
| | - Selma F Witchel
- Division of Pediatric Endocrinology, UPMC Children's Hospital of Pittsburgh, University of Pittsburgh, Pittsburgh, PA
| | - Philip Zeitler
- Division of Pediatric Endocrinology, University of Colorado School of Medicine, Aurora, CO
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19
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Nandedkar-Kulkarni N, Esakov E, Gregg B, Atkinson MA, Rogers DG, Horner JD, Singer K, Lundy SK, Felton JL, Al-Huniti T, Kalinoski AN, Morran MP, Gupta NK, Bretz JD, Balaji S, Chen T, McInerney MF. Insulin Receptor-Expressing T Cells Appear in Individuals at Risk for Type 1 Diabetes and Can Move into the Pancreas in C57BL/6 Transgenic Mice. J Immunol 2021; 206:1443-1453. [PMID: 33658296 DOI: 10.4049/jimmunol.1900357] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Accepted: 01/19/2021] [Indexed: 01/04/2023]
Abstract
Insulin receptor (IR) expression on the T cell surface can indicate an activated state; however, the IR is also chemotactic, enabling T cells with high IR expression to physically move toward insulin. In humans with type 1 diabetes (T1D) and the NOD mouse model, a T cell-mediated autoimmune destruction of insulin-producing pancreatic β cells occurs. In previous work, when purified IR+ and IR- T cells were sorted from diabetic NOD mice and transferred into irradiated nondiabetic NOD mice, only those that received IR+ T cells developed insulitis and diabetes. In this study, peripheral blood samples from individuals with T1D (new onset to 14 y of duration), relatives at high-risk for T1D, defined by positivity for islet autoantibodies, and healthy controls were examined for frequency of IR+ T cells. High-risk individuals had significantly higher numbers of IR+ T cells as compared with those with T1D (p < 0.01) and controls (p < 0.001); however, the percentage of IR+ T cells in circulation did not differ significantly between T1D and control subjects. With the hypothesis that IR+ T cells traffic to the pancreas in T1D, we developed a (to our knowledge) novel mouse model exhibiting a FLAG-tagged mouse IR on T cells on the C57BL/6 background, which is not susceptible to developing T1D. Interestingly, these C57BL/6-CD3FLAGmIR/mfm mice showed evidence of increased IR+ T cell trafficking into the islets compared with C57BL/6 controls (p < 0.001). This transgenic animal model provides a (to our knowledge) novel platform for investigating the influence of IR expression on T cell trafficking and the development of insulitis.
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Affiliation(s)
- Neha Nandedkar-Kulkarni
- Department of Medicinal and Biological Chemistry, College of Pharmacy and Pharmaceutical Sciences, University of Toledo, Toledo, OH 43614
| | - Emily Esakov
- Department of Medicinal and Biological Chemistry, College of Pharmacy and Pharmaceutical Sciences, University of Toledo, Toledo, OH 43614
| | - Brigid Gregg
- Division of Pediatric Endocrinology, Department of Pediatrics, University of Michigan Medical School, Ann Arbor, MI 48109.,Department of Nutritional Sciences, University of Michigan School of Public Health, Ann Arbor, MI 48109
| | - Mark A Atkinson
- Department of Pathology, Immunology and Laboratory Medicine, College of Medicine, University of Florida, Gainesville, FL 32610.,Department of Pediatrics, College of Medicine, University of Florida, Gainesville, FL 32610.,University of Florida Diabetes Institute, University of Florida, Gainesville, FL 32610
| | - Douglas G Rogers
- Center for Pediatric and Adolescent Endocrinology, Cleveland Clinic Foundation, Cleveland, OH 44053
| | - James D Horner
- Department of Pediatrics, College of Medicine and Life Sciences, University of Toledo, Toledo, OH 43614
| | - Kanakadurga Singer
- Division of Pediatric Endocrinology, Department of Pediatrics, University of Michigan Medical School, Ann Arbor, MI 48109.,Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI 48109
| | - Steven K Lundy
- Division of Rheumatology, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, MI 48109
| | - Jamie L Felton
- Department of Pediatric Endocrinology and Diabetology, Indiana University School of Medicine, Indiana University, Indianapolis, IN 46202.,Center for Diabetes and Metabolic Diseases, Indiana University School of Medicine, Indianapolis, IN 46202
| | - Tasneem Al-Huniti
- Department of Medicinal and Biological Chemistry, College of Pharmacy and Pharmaceutical Sciences, University of Toledo, Toledo, OH 43614
| | - Andrea Nestor Kalinoski
- Department of Surgery, College of Medicine and Life Sciences, University of Toledo, Toledo, OH 43614
| | - Michael P Morran
- Department of Surgery, College of Medicine and Life Sciences, University of Toledo, Toledo, OH 43614
| | - Nirdesh K Gupta
- Department of Medicinal and Biological Chemistry, College of Pharmacy and Pharmaceutical Sciences, University of Toledo, Toledo, OH 43614
| | - James D Bretz
- Department of Medicinal and Biological Chemistry, College of Pharmacy and Pharmaceutical Sciences, University of Toledo, Toledo, OH 43614
| | - Swapnaa Balaji
- Department of Medicinal and Biological Chemistry, College of Pharmacy and Pharmaceutical Sciences, University of Toledo, Toledo, OH 43614
| | - Tian Chen
- Department of Mathematics and Statistics, College of Natural Sciences and Mathematics, University of Toledo, Toledo, OH 43606; and
| | - Marcia F McInerney
- Department of Medicinal and Biological Chemistry, College of Pharmacy and Pharmaceutical Sciences, University of Toledo, Toledo, OH 43614; .,Center for Diabetes and Endocrine Research, University of Toledo, Toledo, OH 43614
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20
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Nolt VD, Araya A, Ateya MB, Chen M, Kelley J, Arnold P, Singer K. Insulin Bolus Calculator: Lessons Learned from Institutional Experience. J Diabetes Sci Technol 2021; 15:265-270. [PMID: 32830530 PMCID: PMC8256078 DOI: 10.1177/1932296820950729] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Insulin bolus calculators have proven effective in improving glycemia and patient safety. Insulin calculators are increasingly being implemented for inpatient hospital care. Multidisciplinary teams are often involved in the design and review of the efficacy and utilization for these calculators. At times, unintended consequences and benefits of utilization are found on review. Integration of our insulin calculator into our electronic health record system was a multidisciplinary effort. During implementation, several obstacles to effective care were identified and are discussed in the following manuscript. We describe the barriers to utilization and potential pitfalls in clinical integration. We further describe benefits in patient education, time of insulin administration versus meal delivery, variations in insulin bolus for ketone correction, variation in care, and maximum bolus administration. Sharing lessons learned from experiences using electronic insulin calculator order sets will further our goals of improved patient care in the hospital setting.
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Affiliation(s)
- Valerie D. Nolt
- Department of Pharmacy, University of
Michigan, Ann Arbor, MI, USA
| | - Adrian Araya
- Pediatric Endocrinology, Department of
Pediatrics, University of Michigan, Ann Arbor, MI, USA
| | | | - Ming Chen
- Pediatric Endocrinology, Department of
Pediatrics, University of Michigan, Ann Arbor, MI, USA
| | - Jennifer Kelley
- C.S. Mott Children’s Hospital,
Department of Pediatric Nursing, University of Michigan, Ann Arbor, MI, USA
| | - Patrick Arnold
- Department of Pharmacy, University of
Michigan, Ann Arbor, MI, USA
| | - Kanakadurga Singer
- Pediatric Endocrinology, Department of
Pediatrics, University of Michigan, Ann Arbor, MI, USA
- Kanakadurga Singer, MD, Department of
Pediatrics, Division of Pediatric Endocrinology, D1205 MPB, 1500 E Medical
Center Dr., Ann Arbor, MI 48109, USA.
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21
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Abstract
Obesity and obesity-related diseases like type 2 diabetes (T2D) are prominent global health issues; therefore, there is a need to better understand the mechanisms underlying these conditions. The onset of obesity is characterized by accumulation of proinflammatory cells, including Ly6chi monocytes (which differentiate into proinflammatory macrophages) and neutrophils, in metabolic tissues. This shift toward chronic, low-grade inflammation is an obese-state hallmark and highly linked to metabolic disorders and other obesity comorbidities. The mechanisms that induce and maintain increased inflammatory myelopoiesis are of great interest, with a recent focus on how obesity affects more primitive hematopoietic cells. The hematopoietic system is constantly replenished by proper regulation of hematopoietic stem and progenitor (HSPC) pools in the BM. While early research suggests that chronic obesity promotes expansion of myeloid-skewed HSPCs, the involvement of the hematopoietic stem cell (HSC) niche in regulating obesity-induced myelopoiesis remains undefined. In this review, we explore the role of the multicellular HSC niche in hematopoiesis and inflammation, and the potential contribution of this niche to the hematopoietic response to obesity. This review further aims to summarize the potential HSC niche involvement as a target of obesity-induced inflammation and a driver of obesity-induced myelopoiesis.
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22
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Akhaphong B, Gregg B, Kumusoglu D, Jo S, Singer K, Scheys J, DelProposto J, Lumeng C, Bernal-Mizrachi E, Alejandro EU. Maternal High-Fat Diet During Pre-Conception and Gestation Predisposes Adult Female Offspring to Metabolic Dysfunction in Mice. Front Endocrinol (Lausanne) 2021; 12:780300. [PMID: 35111136 PMCID: PMC8801938 DOI: 10.3389/fendo.2021.780300] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Accepted: 11/24/2021] [Indexed: 01/31/2023] Open
Abstract
The risk of obesity in adulthood is subject to programming in the womb. Maternal obesity contributes to programming of obesity and metabolic disease risk in the adult offspring. With the increasing prevalence of obesity in women of reproductive age there is a need to understand the ramifications of maternal high-fat diet (HFD) during pregnancy on offspring's metabolic heath trajectory. In the present study, we determined the long-term metabolic outcomes on adult male and female offspring of dams fed with HFD during pregnancy. C57BL/6J dams were fed either Ctrl or 60% Kcal HFD for 4 weeks before and throughout pregnancy, and we tested glucose homeostasis in the adult offspring. Both Ctrl and HFD-dams displayed increased weight during pregnancy, but HFD-dams gained more weight than Ctrl-dams. Litter size and offspring birthweight were not different between HFD-dams or Ctrl-dams. A significant reduction in random blood glucose was evident in newborns from HFD-dams compared to Ctrl-dams. Islet morphology and alpha-cell fraction were normal but a reduction in beta-cell fraction was observed in newborns from HFD-dams compared to Ctrl-dams. During adulthood, male offspring of HFD-dams displayed comparable glucose tolerance under normal chow. Male offspring re-challenged with HFD displayed glucose intolerance transiently. Adult female offspring of HFD-dams demonstrated normal glucose tolerance but displayed increased insulin resistance relative to controls under normal chow diet. Moreover, adult female offspring of HFD-dams displayed increased insulin secretion in response to high-glucose treatment, but beta-cell mass were comparable between groups. Together, these data show that maternal HFD at pre-conception and during gestation predisposes the female offspring to insulin resistance in adulthood.
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Affiliation(s)
- Brian Akhaphong
- Department of Integrative Biology & Physiology, University of Minnesota, Minneapolis, MN, United States
| | - Brigid Gregg
- Department of Pediatrics, Division of Diabetes, Endocrinology, and Metabolism, University of Michigan Medical School, Ann Arbor, MI, United States
| | - Doga Kumusoglu
- Department of Internal Medicine, Division of Metabolism, Endocrinology and Diabetes, Brehm Center for Diabetes Research, Ann Arbor, United States
| | - Seokwon Jo
- Department of Integrative Biology & Physiology, University of Minnesota, Minneapolis, MN, United States
| | - Kanakadurga Singer
- Department of Pediatrics, Division of Diabetes, Endocrinology, and Metabolism, University of Michigan Medical School, Ann Arbor, MI, United States
| | - Joshua Scheys
- Department of Internal Medicine, Division of Metabolism, Endocrinology and Diabetes, Brehm Center for Diabetes Research, Ann Arbor, United States
| | - Jennifer DelProposto
- Department of Pediatrics, Division of Diabetes, Endocrinology, and Metabolism, University of Michigan Medical School, Ann Arbor, MI, United States
| | - Carey Lumeng
- Department of Pediatrics, Division of Diabetes, Endocrinology, and Metabolism, University of Michigan Medical School, Ann Arbor, MI, United States
| | - Ernesto Bernal-Mizrachi
- Department of Internal Medicine, Division of Metabolism, Endocrinology and Diabetes, Brehm Center for Diabetes Research, Ann Arbor, United States
- Diabetes, VA Ann Arbor Healthcare System, Ann Arbor, MI, United States
- Miami VA Healthcare System and Division Endocrinology, Metabolism and Diabetes, University of Miami, Miami, FL, United States
- *Correspondence: Ernesto Bernal-Mizrachi, ; Emilyn U. Alejandro,
| | - Emilyn U. Alejandro
- Department of Integrative Biology & Physiology, University of Minnesota, Minneapolis, MN, United States
- Department of Internal Medicine, Division of Metabolism, Endocrinology and Diabetes, Brehm Center for Diabetes Research, Ann Arbor, United States
- *Correspondence: Ernesto Bernal-Mizrachi, ; Emilyn U. Alejandro,
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23
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Morgan HK, Singer K, Fitzgerald JT, Brower KJ, Spencley BM, Owens LE, Burrows HL. Perceptions of Parenting Challenges and Career Progression Among Physician Faculty at an Academic Hospital. JAMA Netw Open 2020; 3:e2029076. [PMID: 33301013 PMCID: PMC7729426 DOI: 10.1001/jamanetworkopen.2020.29076] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
This survey study compares the perceptions of male and female physician faculty members who have children regarding parenting challenges and career progression at an academic hospital.
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Affiliation(s)
- Helen Kang Morgan
- Department of Obstetrics and Gynecology, University of Michigan, Ann Arbor
- Department of Learning Health Sciences, University of Michigan, Ann Arbor
| | | | | | - Kirk J. Brower
- Department of Psychiatry, University of Michigan, Ann Arbor
| | | | - Lauren E. Owens
- Department of Obstetrics and Gynecology, University of Michigan, Ann Arbor
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24
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Safari H, Kaczorowski N, Felder ML, Brannon ER, Varghese M, Singer K, Eniola-Adefeso O. Biodegradable, bile salt microparticles for localized fat dissolution. Sci Adv 2020; 6:eabd8019. [PMID: 33277261 PMCID: PMC7821899 DOI: 10.1126/sciadv.abd8019] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Accepted: 10/20/2020] [Indexed: 05/06/2023]
Abstract
Bile acids are proposed as therapeutic agents for various diseases, including liver diseases and obesity. However, oral or subcutaneous administration of a solubilized version of these drugs has limited efficacy and imposes unwanted side effects. Here, we describe a gold-templating method for fabricating stable, bile salt-cholate or deoxycholate-microparticles. The gold ions' reduction at the oil-water interface in a double emulsion solvent evaporation process enables a gold-bile salt interaction and the formation of bile salt particles. We demonstrate that composite microparticles release cholate/deoxycholate into solution via a surface erosion process. We illustrate these particles' capability to lyse adipocytes, both in vitro and in vivo, with minimal side effects, contrary to the Food and Drug Administration-approved salt solution that leads to severe inflammation and ulceration. Overall, particle-based cholate/deoxycholate opens opportunities for localized delivery of these salts, improving efficacy while minimizing side effects associated with oral and subcutaneous use.
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Affiliation(s)
- Hanieh Safari
- Department of Chemical Engineering, University of Michigan, Ann Arbor, MI 48109, USA
| | - Nicholas Kaczorowski
- Department of Chemical Engineering, University of Michigan, Ann Arbor, MI 48109, USA
| | - Michael L Felder
- Department of Chemical Engineering, University of Michigan, Ann Arbor, MI 48109, USA
| | - Emma R Brannon
- Department of Chemical Engineering, University of Michigan, Ann Arbor, MI 48109, USA
| | - Mita Varghese
- Department of Pediatrics, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - Kanakadurga Singer
- Department of Pediatrics, University of Michigan Medical School, Ann Arbor, MI 48109, USA
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25
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Abstract
In obesity, high levels of saturated fatty acids (SFAs) contribute to adipose tissue inflammation and dysfunction. Obesity-induced macrophage infiltration leads to insulin resistance, but the adipocyte itself may play a role in generating the inflammatory milieu. Given our recent findings of the role of TLR4 in myeloid biasing in obesity, we next investigated the role of TLR4 in adipocyte generated inflammatory responses to SFAs and lipopolysaccharides. We used WT and Tlr4-/- ear mesenchymal stem cell derived adipocytes (EMSC Ad) and bone marrow dendritic cells (BMDCs) to evaluate cell specific responses. Our work demonstrates a role for TLR4 in adipocyte- immune cell crosstalk and that SFA derived metabolites from adipocytes may induce proinflammatory stimulation of immune cells in a TLR4 independent manner.
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Affiliation(s)
- K. McKernan
- Department of Pediatrics and Communicable Disease, University of Michigan Medical School, Ann Arbor, MI, USA
| | - M. Varghese
- Department of Pediatrics and Communicable Disease, University of Michigan Medical School, Ann Arbor, MI, USA
| | - R. Patel
- Department of Pediatrics and Communicable Disease, University of Michigan Medical School, Ann Arbor, MI, USA
| | - K. Singer
- Department of Pediatrics and Communicable Disease, University of Michigan Medical School, Ann Arbor, MI, USA
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26
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Abstract
The coronavirus disease 2019 (COVID-19) pandemic has forced us to consider the physiologic role of obesity in the response to infectious disease. There are significant disparities in morbidity and mortality by sex, weight, and diabetes status. Numerous endocrine changes might drive these varied responses to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, including hormone and immune mediators, hyperglycemia, leukocyte responses, cytokine secretion, and tissue dysfunction. Studies of patients with severe COVID-19 disease have revealed the importance of innate immune responses in driving immunopathology and tissue injury. In this review we will describe the impact of the metabolically induced inflammation (meta-inflammation) that characterizes obesity on innate immunity. We consider that obesity-driven dysregulation of innate immune responses may drive organ injury in the development of severe COVID-19 and impair viral clearance.
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Affiliation(s)
- Gabrielle P Huizinga
- Graduate Program in Immunology, University of Michigan Medical School, Ann Arbor, Michigan
| | - Benjamin H Singer
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, Michigan
- Michigan Center for Integrative Research in Critical Care, University of Michigan Medical School, Ann Arbor, Michigan
| | - Kanakadurga Singer
- Department of Pediatrics and Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, Michigan
- Correspondence: Kanakadurga Singer, MD, Department of Pediatrics and Communicable Diseases, Division of Pediatric Endocrinology, D1205 MPB, 1500 E Medical Center Dr, Ann Arbor, MI 48109, USA. E-mail:
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27
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Ludzki AC, Krueger EM, Baldwin TC, Schleh MW, Porsche CE, Ryan BJ, Muir LA, Singer K, Lumeng CN, Horowitz JF. Acute Aerobic Exercise Remodels the Adipose Tissue Progenitor Cell Phenotype in Obese Adults. Front Physiol 2020; 11:903. [PMID: 32848853 PMCID: PMC7399179 DOI: 10.3389/fphys.2020.00903] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Accepted: 07/06/2020] [Indexed: 12/19/2022] Open
Abstract
Adipose tissue pathology in obese patients often features impaired adipogenesis, angiogenesis, and chronic low-grade inflammation, all of which are regulated in large part by adipose tissue stromal vascular cells [SVC; i.e., non-adipocyte cells within adipose tissue including preadipocytes, endothelial cells (ECs), and immune cells]. Exercise is known to increase subcutaneous adipose tissue lipolysis, but the impact of exercise on SVCs in adipose tissue has not been explored. The purpose of this study was to assess the effects of a session of exercise on preadipocyte, EC, macrophage, and T cell content in human subcutaneous adipose tissue. We collected abdominal subcutaneous adipose tissue samples from 10 obese adults (BMI 33 ± 3 kg/m2, body fat 41 ± 7%) 12 h after a 60 min acute session of endurance exercise (80 ± 3%HRpeak) vs. no acute exercise session. SVCs were isolated by collagenase digestion and stained for flow cytometry. We found that acute exercise reduced preadipocyte content (38 ± 7 vs. 30 ± 13%SVC; p = 0.04). The reduction was driven by a decrease in CD34hi preadipocytes (18 ± 5 vs. 13 ± 6%SVC; p = 0.002), a subset of preadipocytes that generates high lipolytic rate adipocytes ex vivo. Acute exercise did not alter EC content. Acute exercise also did not change total immune cell, macrophage, or T cell content, and future work should assess the effects of exercise on subpopulations of these cells. We conclude that exercise may rapidly regulate the subcutaneous adipose tissue preadipocyte pool in ways that may help attenuate the high lipolytic rates that are commonly found in obesity.
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Affiliation(s)
- Alison C Ludzki
- Substrate Metabolism Laboratory, School of Kinesiology, University of Michigan, Ann Arbor, MI, United States
| | - Emily M Krueger
- Substrate Metabolism Laboratory, School of Kinesiology, University of Michigan, Ann Arbor, MI, United States
| | - Toree C Baldwin
- Substrate Metabolism Laboratory, School of Kinesiology, University of Michigan, Ann Arbor, MI, United States
| | - Michael W Schleh
- Substrate Metabolism Laboratory, School of Kinesiology, University of Michigan, Ann Arbor, MI, United States
| | - Cara E Porsche
- Department of Pediatrics, Medical School, University of Michigan, Ann Arbor, MI, United States.,Graduate Program in Immunology, Medical School, University of Michigan, Ann Arbor, MI, United States
| | - Benjamin J Ryan
- Substrate Metabolism Laboratory, School of Kinesiology, University of Michigan, Ann Arbor, MI, United States
| | - Lindsey A Muir
- Department of Computational Medicine and Bioinformatics, Medical School, University of Michigan, Ann Arbor, MI, United States
| | - Kanakadurga Singer
- Department of Pediatrics, Medical School, University of Michigan, Ann Arbor, MI, United States.,Graduate Program in Immunology, Medical School, University of Michigan, Ann Arbor, MI, United States.,Department of Molecular and Integrative Physiology, Medical School, University of Michigan, Ann Arbor, MI, United States
| | - Carey N Lumeng
- Department of Pediatrics, Medical School, University of Michigan, Ann Arbor, MI, United States.,Graduate Program in Immunology, Medical School, University of Michigan, Ann Arbor, MI, United States.,Department of Molecular and Integrative Physiology, Medical School, University of Michigan, Ann Arbor, MI, United States
| | - Jeffrey F Horowitz
- Substrate Metabolism Laboratory, School of Kinesiology, University of Michigan, Ann Arbor, MI, United States
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28
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Zamarron BF, Porsche CE, Luan D, Lucas HR, Mergian TA, Martinez-Santibanez G, Cho KW, DelProposto JL, Geletka LM, Muir LA, Singer K, Lumeng CN. Weight Regain in Formerly Obese Mice Hastens Development of Hepatic Steatosis Due to Impaired Adipose Tissue Function. Obesity (Silver Spring) 2020; 28:1086-1097. [PMID: 32281747 PMCID: PMC7245566 DOI: 10.1002/oby.22788] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Revised: 01/20/2020] [Accepted: 02/04/2020] [Indexed: 12/19/2022]
Abstract
OBJECTIVE Weight regain after weight loss is common, and there is evidence to suggest negative effects on health because of weight cycling. This study sought to investigate the impact of weight regain in formerly obese mice on adipose tissue architecture and stromal cell function. METHODS A diet-switch model was employed for obesity induction, weight loss, and weight regain in mice. Flow cytometry quantified adipose tissue leukocytes in adipose tissue. Liver and adipose tissue depots were compared to determine tissue-specific effects of weight cycling. RESULTS Epididymal white adipose tissue of formerly obese mice failed to expand in response to repeat exposure to high-fat diet and retained elevated numbers of macrophages and T cells. Weight regain was associated with disproportionally elevated liver mass, hepatic triglyceride content, serum insulin concentration, and serum transaminase concentration. These effects occurred despite an extended 6-month weight loss cycle and they demonstrate that formerly obese mice maintain durable alterations in their physiological response to weight regain. Conditioned media from epididymal adipose tissue of formerly obese mice inhibited adipogenesis of 3T3-L1 preadipocytes, suggesting a potential mechanism to explain failed epididymal adipose tissue expansion during weight regain. CONCLUSIONS Metabolic abnormalities related to defects in adipose tissue expansion and ongoing dysfunction manifest in formerly obese mice during weight regain.
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Affiliation(s)
- Brian F Zamarron
- Graduate Program in Immunology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Cara E Porsche
- Graduate Program in Immunology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Danny Luan
- College of Literature Sciences and Arts, University of Michigan, Ann Arbor, Michigan, USA
| | - Hannah R Lucas
- College of Literature Sciences and Arts, University of Michigan, Ann Arbor, Michigan, USA
| | - Taleen A Mergian
- College of Literature Sciences and Arts, University of Michigan, Ann Arbor, Michigan, USA
| | - Gabriel Martinez-Santibanez
- Graduate Program in Cellular and Molecular Biology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Kae Won Cho
- Soonchunhyang Institute of Medi-Bio Science, Soonchunhyang University, Cheonan-si, Chungcheongnam-do, Korea
| | - Jennifer L DelProposto
- Department of Pediatrics, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Lynn M Geletka
- Department of Pediatrics, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Lindsey A Muir
- Department of Pediatrics, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Kanakadurga Singer
- Graduate Program in Immunology, University of Michigan Medical School, Ann Arbor, Michigan, USA
- Department of Pediatrics, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Carey N Lumeng
- Graduate Program in Immunology, University of Michigan Medical School, Ann Arbor, Michigan, USA
- Graduate Program in Cellular and Molecular Biology, University of Michigan Medical School, Ann Arbor, Michigan, USA
- Department of Pediatrics, University of Michigan Medical School, Ann Arbor, Michigan, USA
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29
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Davis FM, denDekker A, Kimball A, Joshi AD, El Azzouny M, Wolf SJ, Obi AT, Lipinski J, Gudjonsson JE, Xing X, Plazyo O, Audu C, Melvin WJ, Singer K, Henke PK, Moore BB, Burant C, Kunkel SL, Gallagher KA. Epigenetic Regulation of TLR4 in Diabetic Macrophages Modulates Immunometabolism and Wound Repair. J Immunol 2020; 204:2503-2513. [PMID: 32205424 DOI: 10.4049/jimmunol.1901263] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Accepted: 02/21/2020] [Indexed: 12/17/2022]
Abstract
Macrophages are critical for the initiation and resolution of the inflammatory phase of wound healing. In diabetes, macrophages display a prolonged inflammatory phenotype preventing tissue repair. TLRs, particularly TLR4, have been shown to regulate myeloid-mediated inflammation in wounds. We examined macrophages isolated from wounds of patients afflicted with diabetes and healthy controls as well as a murine diabetic model demonstrating dynamic expression of TLR4 results in altered metabolic pathways in diabetic macrophages. Further, using a myeloid-specific mixed-lineage leukemia 1 (MLL1) knockout (Mll1f/fLyz2Cre+ ), we determined that MLL1 drives Tlr4 expression in diabetic macrophages by regulating levels of histone H3 lysine 4 trimethylation on the Tlr4 promoter. Mechanistically, MLL1-mediated epigenetic alterations influence diabetic macrophage responsiveness to TLR4 stimulation and inhibit tissue repair. Pharmacological inhibition of the TLR4 pathway using a small molecule inhibitor (TAK-242) as well as genetic depletion of either Tlr4 (Tlr4-/- ) or myeloid-specific Tlr4 (Tlr4f/fLyz2Cre+) resulted in improved diabetic wound healing. These results define an important role for MLL1-mediated epigenetic regulation of TLR4 in pathologic diabetic wound repair and suggest a target for therapeutic manipulation.
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Affiliation(s)
- Frank M Davis
- Section of Vascular Surgery, Department of Surgery, University of Michigan, Ann Arbor, MI 48109
| | - Aaron denDekker
- Section of Vascular Surgery, Department of Surgery, University of Michigan, Ann Arbor, MI 48109
| | - Andrew Kimball
- Section of Vascular Surgery, Department of Surgery, University of Alabama Birmingham, Birmingham, AL 35233
| | - Amrita D Joshi
- Section of Vascular Surgery, Department of Surgery, University of Michigan, Ann Arbor, MI 48109
| | | | - Sonya J Wolf
- Section of Vascular Surgery, Department of Surgery, University of Michigan, Ann Arbor, MI 48109
| | - Andrea T Obi
- Section of Vascular Surgery, Department of Surgery, University of Michigan, Ann Arbor, MI 48109
| | - Jay Lipinski
- Department of Pathology, University of Michigan, Ann Arbor, MI 48109
| | | | - Xianying Xing
- Department of Dermatology, University of Michigan, Ann Arbor, MI 48109
| | - Olesya Plazyo
- Department of Dermatology, University of Michigan, Ann Arbor, MI 48109
| | - Christopher Audu
- Section of Vascular Surgery, Department of Surgery, University of Michigan, Ann Arbor, MI 48109
| | - William J Melvin
- Section of Vascular Surgery, Department of Surgery, University of Michigan, Ann Arbor, MI 48109
| | - Kanakadurga Singer
- Section of Endocrinology, Department of Pediatrics, University of Michigan, Ann Arbor, MI 48109
| | - Peter K Henke
- Section of Vascular Surgery, Department of Surgery, University of Michigan, Ann Arbor, MI 48109
| | - Bethany B Moore
- Department of Internal Medicine, University of Michigan, Ann Arbor, MI 48109; and.,Department Microbiology and Immunology, University of Michigan, Ann Arbor, MI 48109
| | - Charles Burant
- Department of Internal Medicine, University of Michigan, Ann Arbor, MI 48109; and
| | - Steven L Kunkel
- Department of Pathology, University of Michigan, Ann Arbor, MI 48109
| | - Katherine A Gallagher
- Section of Vascular Surgery, Department of Surgery, University of Michigan, Ann Arbor, MI 48109; .,Department Microbiology and Immunology, University of Michigan, Ann Arbor, MI 48109
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Puttabyatappa M, Ciarelli JN, Chatoff AG, Singer K, Padmanabhan V. Developmental programming: Adipose depot-specific changes and thermogenic adipocyte distribution in the female sheep. Mol Cell Endocrinol 2020; 503:110691. [PMID: 31863810 PMCID: PMC7012762 DOI: 10.1016/j.mce.2019.110691] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Revised: 12/04/2019] [Accepted: 12/17/2019] [Indexed: 12/17/2022]
Abstract
Prenatal testosterone (T)-treated female sheep exhibit an enhanced inflammatory and oxidative stress state in the visceral adipose tissue (VAT) but not in the subcutaneous (SAT), while surprisingly maintaining insulin sensitivity in both depots. In adult sheep, adipose tissue is predominantly composed of white adipocytes which favor lipid storage. Brown/beige adipocytes that make up the brown adipose tissue (BAT) favor lipid utilization due to thermogenic uncoupled protein 1 expression and are interspersed amidst white adipocytes, more so in epicardiac (ECAT) and perirenal (PRAT) depots. The impact of prenatal T-treatment on ECAT and PRAT depots are unknown. As BAT imparts a metabolically healthy phenotype, the depot-specific impact of prenatal T-treatment on inflammation, oxidative stress, differentiation and insulin sensitivity could be dictated by the distribution of brown adipocytes. This hypothesis was tested by assessing markers of oxidative stress, inflammation, adipocyte differentiation, fibrosis and thermogenesis in adipose depots from control and prenatal T (100 mg T propionate twice a week from days 30-90 of gestation) -treated female sheep at 21 months of age. Our results show prenatal T-treatment induces depot-specific changes in inflammation, oxidative stress state, collagen accumulation, and differentiation with changes being more pronounced in the VAT. Prenatal T-treatment also increased thermogenic gene expression in all depots indicative of increased browning with effects being more prominent in VAT and SAT. Considering that inflammatory and oxidative stress are also elevated, the increased brown adipocyte distribution is likely a compensatory response to maintain insulin sensitivity and function of organs in the proximity of respective depots.
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Affiliation(s)
| | - Joseph N Ciarelli
- Department of Pediatrics, University of Michigan, Ann Arbor, MI, USA
| | - Adam G Chatoff
- Department of Pediatrics, University of Michigan, Ann Arbor, MI, USA
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Sakowski SA, Feldman EL, Jagsi R, Singer K. Energizing the Conversation: How to Identify and Overcome Gender Inequalities in Academic Medicine. J Contin Educ Health Prof 2020; 40:274-278. [PMID: 33284179 PMCID: PMC8328536 DOI: 10.1097/ceh.0000000000000296] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Gender inequality exists in advanced faculty and leadership positions at academic medical centers; however, despite growing awareness, how to best approach and rectify the issue is unknown. To energize the conversation on gender inequality at one academic medical center, chairs and women faculty were surveyed to identify barriers faced by women navigating their careers. A symposium with short talks to increase awareness, a panel with University leaders to discuss issues and successful strategies to overcome gaps, and focus groups to delve further into key areas that underlie inequity through an active café style format were planned and implemented. This multifaceted approach resulted in a wealth of knowledge. The symposium and panel highlighted important relevant issues and offered personal strategies for successful career advancement, while the focus group discussions further identified barriers and inspired ongoing efforts across departments and novel approaches to overcome three key issues (work-life integration, deliberate promotion of mentor/sponsor relationships, and overcoming unconscious bias) identified through the initial surveys. Compiled data were then disseminated to participants and University leaders to enhance awareness of available programs and prompt action in critical areas lacking support. Overall, the approach indicated that securing support from leaders and the academic community alike are pertinent to emphasize actions needed to overcome issues affecting women in academic medicine. Moreover, bringing leaders and faculty together for an informational session and brainstorming appears to energize the conversation. Such efforts can ultimately instill change and establish an inclusive environment where all members of the academic medicine community can thrive.
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Affiliation(s)
| | - Eva L. Feldman
- Department of Neurology, University of Michigan, Ann Arbor, Michigan
| | - Reshma Jagsi
- Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan
- Center for Bioethics and Social Sciences in Medicine, University of Michigan, Ann Arbor, Michigan
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Gállego-Suárez C, Bulan A, Hirschfeld E, Wachowiak P, Abrishami S, Griffin C, Sturza J, Tzau A, Hayes T, Woolford SJ, Lumeng CN, Lee JM, Singer K. Enhanced Myeloid Leukocytes in Obese Children and Adolescents at Risk for Metabolic Impairment. Front Endocrinol (Lausanne) 2020; 11:327. [PMID: 32528415 PMCID: PMC7266967 DOI: 10.3389/fendo.2020.00327] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Accepted: 04/27/2020] [Indexed: 12/26/2022] Open
Abstract
Objective: We aimed to examine if myeloid leukocyte profiles are associated with metabolic impairment in children and adolescents with obesity, and if sex, age, or race influence this relationship. Methods: 282 children ages 8-17 were evaluated. Predictor measures were absolute neutrophil counts (ANC), absolute monocyte count, monocyte subtypes and C reactive protein (CRP). Outcome variables were waist circumference, fasting glucose and insulin, HOMA-IR, HbA1c (%) and lipid profiles. Pearson correlation coefficients were used to determine associations between predictor and outcome variables. Wilcoxon two-sample tests were used to evaluate differences by sex. Results: CRP (p < 0.0001), ANC (p < 0.0018), and classical monocytes (p = 0.05) were significantly higher in children with obesity. CRP, ANC and classical monocytes showed positive correlations with waist circumference, insulin, HOMA-IR and triglycerides. CRP was positively associated with ANC overall (p = 0.05). ANC demonstrated positive correlation with monocytes (p < 0.001). The associations between predictor and outcome variables were influenced by sex, race, and age. Conclusions: CRP and myeloid leukocyte populations, specifically classical monocytes and neutrophils associate with both body composition and metabolic parameters in children with obesity suggesting that these cells may play a critical role in metabolic impairment. Race, gender and age interactions between monocytes and metabolic parameters were significant.
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Affiliation(s)
- Cecilia Gállego-Suárez
- Division of Pediatric Endocrinology, Department of Pediatrics, University of Michigan, Ann Arbor, MI, United States
| | - Ayse Bulan
- Division of Pediatric Endocrinology, Department of Pediatrics, University of Michigan, Ann Arbor, MI, United States
| | - Emily Hirschfeld
- Department of Pediatrics, Child Health Evaluation and Research Center (CHEAR), University of Michigan, Ann Arbor, MI, United States
| | - Phillip Wachowiak
- Division of Pediatric Endocrinology, Department of Pediatrics, University of Michigan, Ann Arbor, MI, United States
| | - Simin Abrishami
- Division of Pediatric Endocrinology, Department of Pediatrics, University of Michigan, Ann Arbor, MI, United States
| | - Cameron Griffin
- Division of Pediatric Endocrinology, Department of Pediatrics, University of Michigan, Ann Arbor, MI, United States
| | - Julie Sturza
- Woodson Biostatistics Consultation Program, Department of Pediatrics, University of Michigan, Ann Arbor, MI, United States
| | - Abigail Tzau
- Division of Pediatric Endocrinology, Department of Pediatrics, University of Michigan, Ann Arbor, MI, United States
| | - Taryn Hayes
- Division of Pediatric Endocrinology, Department of Pediatrics, University of Michigan, Ann Arbor, MI, United States
| | - Susan J. Woolford
- Department of Pediatrics, Child Health Evaluation and Research Center (CHEAR), University of Michigan, Ann Arbor, MI, United States
| | - Carey N. Lumeng
- Graduate Program in Immunology, University of Michigan Medical School, Ann Arbor, MI, United States
- Graduate Program in Cellular and Molecular Biology, University of Michigan Medical School, Ann Arbor, MI, United States
| | - Joyce M. Lee
- Division of Pediatric Endocrinology, Department of Pediatrics, University of Michigan, Ann Arbor, MI, United States
- Department of Pediatrics, Child Health Evaluation and Research Center (CHEAR), University of Michigan, Ann Arbor, MI, United States
| | - Kanakadurga Singer
- Division of Pediatric Endocrinology, Department of Pediatrics, University of Michigan, Ann Arbor, MI, United States
- Graduate Program in Immunology, University of Michigan Medical School, Ann Arbor, MI, United States
- Graduate Program in Cellular and Molecular Biology, University of Michigan Medical School, Ann Arbor, MI, United States
- *Correspondence: Kanakadurga Singer
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33
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Chang E, Hafner H, Varghese M, Griffin C, Clemente J, Islam M, Carlson Z, Zhu A, Hak L, Abrishami S, Gregg B, Singer K. Programming effects of maternal and gestational obesity on offspring metabolism and metabolic inflammation. Sci Rep 2019; 9:16027. [PMID: 31690792 PMCID: PMC6831633 DOI: 10.1038/s41598-019-52583-x] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Accepted: 10/21/2019] [Indexed: 01/07/2023] Open
Abstract
With the increasing prevalence of obesity in women of reproductive age there is a need to understand the ramifications of this on offspring. The purpose of this study is to investigate the programming effects of maternal obesity during preconception and the preconception/gestational period on adiposity and adipose tissue inflammation in offspring using an animal model. Adult female C57Bl/6J mice were assigned either normal diet, high fat diet (HFD) prior to pregnancy, or HFD prior to and through pregnancy. Some offspring were maintained on normal diet while others started HFD later in life. Offspring were assessed for body composition and metabolic responses. Lipid storing tissues were evaluated for expansion and inflammation. Male offspring from the preconception group had the greatest weight gain, most subcutaneous adipose tissue, and largest liver mass when introduced to postnatal HFD. Male offspring of the preconception/gestation group had worsened glucose tolerance and an increase in resident (CD11c−) adipose tissue macrophages (ATMs) when exposed to postnatal HFD. Female offspring had no significant difference in any parameter between the diet treatment groups. In conclusion, this study demonstrates that prenatal and pregnancy windows have independent programming effects on offspring. Preconception exposure affects body composition and adiposity while gestation exposure affects metabolism and tissue immune cell phenotypes.
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Affiliation(s)
- E Chang
- Department of Pediatrics, Division of Diabetes, Endocrinology, and Metabolism, University of Michigan Medical School, Ann Arbor, MI, USA
| | - H Hafner
- Department of Pediatrics, Division of Diabetes, Endocrinology, and Metabolism, University of Michigan Medical School, Ann Arbor, MI, USA
| | - M Varghese
- Department of Pediatrics, Division of Diabetes, Endocrinology, and Metabolism, University of Michigan Medical School, Ann Arbor, MI, USA
| | - C Griffin
- Department of Pediatrics, Division of Diabetes, Endocrinology, and Metabolism, University of Michigan Medical School, Ann Arbor, MI, USA
| | - J Clemente
- Department of Pediatrics, Division of Diabetes, Endocrinology, and Metabolism, University of Michigan Medical School, Ann Arbor, MI, USA
| | - M Islam
- Department of Pediatrics, Division of Diabetes, Endocrinology, and Metabolism, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Z Carlson
- Department of Pediatrics, Division of Diabetes, Endocrinology, and Metabolism, University of Michigan Medical School, Ann Arbor, MI, USA
| | - A Zhu
- Department of Pediatrics, Division of Diabetes, Endocrinology, and Metabolism, University of Michigan Medical School, Ann Arbor, MI, USA
| | - L Hak
- Department of Pediatrics, Division of Diabetes, Endocrinology, and Metabolism, University of Michigan Medical School, Ann Arbor, MI, USA
| | - S Abrishami
- Department of Pediatrics, Division of Diabetes, Endocrinology, and Metabolism, University of Michigan Medical School, Ann Arbor, MI, USA
| | - B Gregg
- Department of Pediatrics, Division of Diabetes, Endocrinology, and Metabolism, University of Michigan Medical School, Ann Arbor, MI, USA
| | - K Singer
- Department of Pediatrics, Division of Diabetes, Endocrinology, and Metabolism, University of Michigan Medical School, Ann Arbor, MI, USA.
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Affiliation(s)
- Reshma Jagsi
- Center for Bioethics and Social Sciences in Medicine, University of Michigan, Ann Arbor
| | | | - Eve Kerr
- Department of Internal Medicine, University of Michigan, Ann Arbor
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Pesch MH, Tomlinson S, Singer K, Burrows HL. Reply. J Pediatr 2019; 211:226. [PMID: 31160059 DOI: 10.1016/j.jpeds.2019.05.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Accepted: 05/02/2019] [Indexed: 11/18/2022]
Affiliation(s)
| | | | | | - Heather L Burrows
- Department of Pediatrics, University of Michigan, Ann Arbor, Michigan
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Hafner H, Chang E, Carlson Z, Zhu A, Varghese M, Clemente J, Abrishami S, Bagchi DP, MacDougald OA, Singer K, Gregg B. Lactational High-Fat Diet Exposure Programs Metabolic Inflammation and Bone Marrow Adiposity in Male Offspring. Nutrients 2019; 11:nu11061393. [PMID: 31234301 PMCID: PMC6628038 DOI: 10.3390/nu11061393] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Revised: 06/01/2019] [Accepted: 06/18/2019] [Indexed: 12/12/2022] Open
Abstract
Overnutrition during critical windows of development plays a significant role in life-long metabolic disease risk. Early exposure to excessive nutrition may result in altered programming leading to increased susceptibility to obesity, inflammation, and metabolic complications. This study investigated the programming effects of high-fat diet (HFD) exposure during the lactation period on offspring adiposity and inflammation. Female C57Bl/6J dams were fed a normal diet or a 60% HFD during lactation. Offspring were weaned onto a normal diet until 12 weeks of age when half were re-challenged with HFD for 12 weeks. Metabolic testing was performed throughout adulthood. At 24 weeks, adipose depots were isolated and evaluated for macrophage profiling and inflammatory gene expression. Males exposed to HFD during lactation had insulin resistance and glucose intolerance as adults. After re-introduction to HFD, males had increased weight gain and worsened insulin resistance and hyperglycemia. There was increased infiltration of pro-inflammatory CD11c+ adipose tissue macrophages, and bone marrow was primed to produce granulocytes and macrophages. Bone density was lower due to enhanced marrow adiposity. This study demonstrates that maternal HFD exposure during the lactational window programs offspring adiposity, inflammation, and impaired glucose homeostasis.
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Affiliation(s)
- Hannah Hafner
- Division of Diabetes, Endocrinology and Metabolism, Department of Pediatrics, University of Michigan Medicine, Ann Arbor, MI 48105, USA.
| | - Eric Chang
- Division of Diabetes, Endocrinology and Metabolism, Department of Pediatrics, University of Michigan Medicine, Ann Arbor, MI 48105, USA.
| | - Zach Carlson
- Division of Diabetes, Endocrinology and Metabolism, Department of Pediatrics, University of Michigan Medicine, Ann Arbor, MI 48105, USA.
| | - Allen Zhu
- Division of Diabetes, Endocrinology and Metabolism, Department of Pediatrics, University of Michigan Medicine, Ann Arbor, MI 48105, USA.
| | - Mita Varghese
- Division of Diabetes, Endocrinology and Metabolism, Department of Pediatrics, University of Michigan Medicine, Ann Arbor, MI 48105, USA.
| | - Jeremy Clemente
- Division of Diabetes, Endocrinology and Metabolism, Department of Pediatrics, University of Michigan Medicine, Ann Arbor, MI 48105, USA.
| | - Simin Abrishami
- Division of Diabetes, Endocrinology and Metabolism, Department of Pediatrics, University of Michigan Medicine, Ann Arbor, MI 48105, USA.
| | - Devika P Bagchi
- Department of Molecular & Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI 48105, USA.
| | - Ormond A MacDougald
- Department of Molecular & Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI 48105, USA.
| | - Kanakadurga Singer
- Division of Diabetes, Endocrinology and Metabolism, Department of Pediatrics, University of Michigan Medicine, Ann Arbor, MI 48105, USA.
| | - Brigid Gregg
- Division of Diabetes, Endocrinology and Metabolism, Department of Pediatrics, University of Michigan Medicine, Ann Arbor, MI 48105, USA.
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Li Z, Hardij J, Evers SS, Hutch CR, Choi SM, Shao Y, Learman BS, Lewis KT, Schill RL, Mori H, Bagchi DP, Romanelli SM, Kim KS, Bowers E, Griffin C, Seeley RJ, Singer K, Sandoval DA, Rosen CJ, MacDougald OA. G-CSF partially mediates effects of sleeve gastrectomy on the bone marrow niche. J Clin Invest 2019; 129:2404-2416. [PMID: 31063988 PMCID: PMC6546463 DOI: 10.1172/jci126173] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Accepted: 03/05/2019] [Indexed: 01/26/2023] Open
Abstract
Bariatric surgeries are integral to the management of obesity and its metabolic complications. However, these surgeries cause bone loss and increase fracture risk through poorly understood mechanisms. In a mouse model, vertical sleeve gastrectomy (VSG) caused trabecular and cortical bone loss that was independent of sex, body weight, and diet, and this loss was characterized by impaired osteoid mineralization and bone formation. VSG had a profound effect on the bone marrow niche, with rapid loss of marrow adipose tissue, and expansion of myeloid cellularity, leading to increased circulating neutrophils. Following VSG, circulating granulocyte-colony stimulating factor (G-CSF) was increased in mice, and was transiently elevated in a longitudinal study of humans. Elevation of G-CSF was found to recapitulate many effects of VSG on bone and the marrow niche. In addition to stimulatory effects of G-CSF on myelopoiesis, endogenous G-CSF suppressed development of marrow adipocytes and hindered accrual of peak cortical and trabecular bone. Effects of VSG on induction of neutrophils and depletion of marrow adiposity were reduced in mice deficient for G-CSF; however, bone mass was not influenced. Although not a primary mechanism for bone loss with VSG, G-CSF plays an intermediary role for effects of VSG on the bone marrow niche.
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Affiliation(s)
- Ziru Li
- Department of Molecular & Integrative Physiology
| | - Julie Hardij
- Department of Molecular & Integrative Physiology
| | | | | | | | | | | | | | | | | | | | | | | | - Emily Bowers
- Department of Pediatrics and Communicable Diseases, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Cameron Griffin
- Department of Pediatrics and Communicable Diseases, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | | | - Kanakadurga Singer
- Department of Pediatrics and Communicable Diseases, University of Michigan Medical School, Ann Arbor, Michigan, USA
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Varghese M, Griffin C, McKernan K, Hayes T, Abrishami S, Singer K. SUN-105 Females Have Reduced Meta-Inflammation in Two States of Increased Adiposity, Obesity, and Aging. J Endocr Soc 2019. [PMCID: PMC6553001 DOI: 10.1210/js.2019-sun-105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Obesity is a global health epidemic, closely associated with cardiovascular diseases (CVD), hypertension, type 2 diabetes, and atherosclerosis. Obese adipose tissue is a site and source for inflammation that is strongly associated with these metabolic diseases. In obese mice models, males exhibit profound adipose tissue macrophage (ATM) accumulation in gonadal white adipose tissue (GWAT) linked to insulin resistance, while females are protected even with enhanced adiposity. This dampened inflammation may directly explain reduced metabolic and cardiovascular disease in young women. However, it is not clear what metabolic and inflammatory responses occur in post-menopausal models. We hypothesized an increased inflammatory response would occur in obese older females. We challenged male and female C57Bl6/j mice to 16-24 weeks of 60% high fat diet (HFD) starting at 6 weeks of age (young) or 10 month of age (old). Animal body weights and metabolic depot (adipose and liver) weights were measured at the completion of diet challenge. Flow cytometry was used to determine ATM populations in visceral (GWAT) compared to subcutaneous inguinal WAT (IWAT). Lipolysis was stimulated with a beta3 adrenergic receptor (ADRB3) agonist CL-316, 243 and free fatty acids (FFA), glycerol, and triglyceride (TG) levels assessed in serum and liver. Obesity in young mice led to fat accumulation in GWAT and IWAT of both males and females. In old male animals, fat pads did not expand, and liver weights were as a result larger than in females. Both young and old females had reduced adipose inflammation compared to males. ADRB3 activation had no effect on adipose tissue weights but significantly increased liver weights in obese young females. Obese CL treated young and old female mice showed elevated FFA compared to levels induced in males. Lipolysis promoted appearance of crown like structures (CLS) in both obese young and old males and females, due to CD11c- ATM accumulation. Obesity during aging continues to lead to enhanced inflammation in males along with steatosis but females continue to be protected with appropriate storage of fatty acids with very little induced inflammation. Sex differences in inflammation that persist in aging demonstrate that differences in meta-inflammation may explain sex differences in metabolic and cardiovascular diseases regardless of age and need to be further explored for targeted treatment strategies.
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Affiliation(s)
- Mita Varghese
- University of Michigan, Ann Arbor, MI, United States
| | | | | | - Taryn Hayes
- University of Michigan, Ann Arbor, MI, United States
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Griffin C, Hutch CR, Abrishami S, Stelmak D, Eter L, Li Z, Chang E, Agarwal D, Zamarron B, Varghese M, Subbaiah P, MacDougald OA, Sandoval DA, Singer K. Inflammatory responses to dietary and surgical weight loss in male and female mice. Biol Sex Differ 2019; 10:16. [PMID: 30944030 PMCID: PMC6446331 DOI: 10.1186/s13293-019-0229-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/03/2019] [Accepted: 03/14/2019] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Weight loss by surgery or lifestyle changes is strongly recommended for obese individuals to improve metabolic health, but the underlying impairments that persist from a history of obesity remain unclear. Recent investigations demonstrate a persistent inflammatory state with weight loss and bariatric surgery, but the mechanism and impact are not fully understood. Additionally, these studies have not been performed in females although women are the majority of individuals undergoing weight loss interventions. METHODS The goal of this study was to determine the sex differences in metabolically induced inflammation after dietary weight loss (WL) or bariatric surgery. Following a 60% high-fat diet (HFD) for 12 weeks, C57Bl/6j mice underwent either a dietary switch to normal chow for WL or vertical sleeve gastrectomy (VSG) and were evaluated 8 weeks after intervention. WL effects on myelopoiesis were further evaluated with bone marrow chimeras. RESULTS Both sexes had a decrease in adiposity and total weight following WL or VSG intervention. With HFD, females had very little inflammation and no further increase with WL, but males had persistent inflammation even after WL despite metabolic improvement. Interestingly, after VSG, myeloid inflammation was increased in the livers of males and to a lesser extent in females. CONCLUSIONS These studies demonstrate that regardless of sex, it is critical to assess an individuals' history of obesity rather than just rely on current weight status in medical decision-making. There are long-lasting effects on tissue inflammation in both sexes especially with surgical weight loss. Dietary change is overall most effective to improve meta-inflammation in obese males on its own or in combination with surgical weight loss.
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Affiliation(s)
- Cameron Griffin
- Department of Pediatrics, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Chelsea R Hutch
- Department of Surgery, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Simin Abrishami
- Department of Pediatrics, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Daria Stelmak
- Department of Surgery, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Leila Eter
- Department of Pediatrics, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Ziru Li
- Department Molecular & Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Eric Chang
- Department of Pediatrics, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Devyani Agarwal
- Department of Pediatrics, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Brian Zamarron
- Department of Pediatrics, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Mita Varghese
- Department of Pediatrics, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Perla Subbaiah
- Department of Mathematics and Statistics, Oakland University, Rochester, MI, 48309, USA
| | - Ormond A MacDougald
- Department Molecular & Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Darleen A Sandoval
- Department of Surgery, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Kanakadurga Singer
- Department of Pediatrics, University of Michigan Medical School, Ann Arbor, MI, USA. .,Department of Pediatrics, Division of Pediatric Endocrinology, D1205 MPB, 1500 E Medical Center Dr., Ann Arbor, MI, 48109, USA.
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Pesch MH, Tomlinson S, Singer K, Burrows HL. Pediatricians Advocating Breastfeeding: Let's Start with Supporting our Fellow Pediatricians First. J Pediatr 2019; 206:6-7. [PMID: 30798838 DOI: 10.1016/j.jpeds.2018.12.057] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/28/2018] [Accepted: 12/28/2018] [Indexed: 11/29/2022]
Affiliation(s)
- Megan H Pesch
- Department of Pediatrics, University of Michigan, Ann Arbor, MI.
| | - Sarah Tomlinson
- Department of Pediatrics, University of Michigan, Ann Arbor, MI; Department of Emergency Medicine, University of Michigan, Ann Arbor, MI
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Varghese M, Griffin C, McKernan K, Eter L, Lanzetta N, Agarwal D, Abrishami S, Singer K. Sex Differences in Inflammatory Responses to Adipose Tissue Lipolysis in Diet-Induced Obesity. Endocrinology 2019; 160:293-312. [PMID: 30544158 PMCID: PMC6330175 DOI: 10.1210/en.2018-00797] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Accepted: 12/09/2018] [Indexed: 02/08/2023]
Abstract
Males are known to have profound adipose tissue macrophage (ATM) accumulation in gonadal white adipose tissue (GWAT) during obesity, whereas females are protected from such an inflammatory response even with increased adiposity. The inflammatory tone in males is linked to insulin resistance and might be the underlying cause for sex differences in metabolic disease. Factors regulating the meta-inflammatory response remain unclear but enhanced lipid storage in females may explain the reduced inflammatory response to high-fat diets. In this study, we evaluated lean and obese females with stimulated lipolysis to understand whether a stress release of free fatty acids (FFAs) could induce female ATMs. We demonstrate that in both lean and obese females, GWAT CD11c- resident ATMs accumulate with β-3 adrenergic receptor-stimulated lipolysis. Lipolysis elevated serum FFA, triglyceride, and IL-6 levels in females that corresponded to significant phosphorylated hormone-sensitive lipase and adipose triglyceride lipase protein expression in obese female GWAT compared with males. Increased lipolytic response in obese females was associated with crown-like structures and induced Il6, Mcp1, Arg1, and Mgl1 expression in obese female GWAT, suggesting an environment of lipid clearance and adipose remodeling. With this finding we next investigated whether lipid storage and lipolytic mediators differed by sex. Diacylglycerol, ceramides, phospholipids, and certain fatty acid species associated with inflammation were elevated in male GWAT compared with obese female GWAT. Overall, our data demonstrate a role for GWAT lipid storage and lipolytic metabolites to induce inflammation in males and induce remodeling in females that might explain sex differences in overall metabolic health.
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Affiliation(s)
- Mita Varghese
- Department of Pediatrics and Communicable Disease, University of Michigan Medical School, Ann Arbor, Michigan
| | - Cameron Griffin
- Department of Pediatrics and Communicable Disease, University of Michigan Medical School, Ann Arbor, Michigan
| | - Kaitlin McKernan
- Department of Pediatrics and Communicable Disease, University of Michigan Medical School, Ann Arbor, Michigan
| | - Leila Eter
- Department of Pediatrics and Communicable Disease, University of Michigan Medical School, Ann Arbor, Michigan
| | - Nicholas Lanzetta
- Department of Pediatrics and Communicable Disease, University of Michigan Medical School, Ann Arbor, Michigan
| | - Devyani Agarwal
- Department of Pediatrics and Communicable Disease, University of Michigan Medical School, Ann Arbor, Michigan
| | - Simin Abrishami
- Department of Pediatrics and Communicable Disease, University of Michigan Medical School, Ann Arbor, Michigan
| | - Kanakadurga Singer
- Department of Pediatrics and Communicable Disease, University of Michigan Medical School, Ann Arbor, Michigan
- Correspondence: Kanakadurga Singer, MD, Department of Pediatrics and Communicable Diseases, Division of Pediatric Endocrinology, D1205 MPB, 1500 East Medical Center Drive, Ann Arbor, Michigan 48109. E-mail:
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Davis FM, Kimball A, denDekker A, Joshi AD, Boniakowski AE, Nysz D, Allen RM, Obi A, Singer K, Henke PK, Moore BB, Kunkel SL, Gallagher KA. Histone Methylation Directs Myeloid TLR4 Expression and Regulates Wound Healing following Cutaneous Tissue Injury. J Immunol 2019; 202:1777-1785. [PMID: 30710046 DOI: 10.4049/jimmunol.1801258] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Accepted: 01/03/2019] [Indexed: 12/27/2022]
Abstract
Myeloid cells are critical for orchestrating regulated inflammation during wound healing. TLRs, particularly TLR4, and its downstream-signaling MyD88 pathway play an important role in regulating myeloid-mediated inflammation. Because an initial inflammatory phase is vital for tissue repair, we investigated the role of TLR4-regulated, myeloid-mediated inflammation in wound healing. In a cutaneous tissue injury murine model, we found that TLR4 expression is dynamic in wound myeloid cells during the course of normal wound healing. We identified that changes in myeloid TLR4 during tissue repair correlated with increased expression of the histone methyltransferase, mixed-lineage leukemia 1 (MLL1), which specifically trimethylates the histone 3 lysine 4 (H3K4me3) position of the TLR4 promoter. Furthermore, we used a myeloid-specific Mll1 knockout (Mll1f/fLyz2Cre+ ) to determine MLL1 drives Tlr4 expression during wound healing. To understand the critical role of myeloid-specific TLR4 signaling, we used mice deficient in Tlr4 (Tlr4-/- ), Myd88 (Myd88 -/-), and myeloid-specific Tlr4 (Tlr4f/fLyz2Cre+) to demonstrate delayed wound healing at early time points postinjury. Furthermore, in vivo wound myeloid cells isolated from Tlr4-/- and Myd88 -/- wounds demonstrated decreased inflammatory cytokine production. Importantly, adoptive transfer of monocyte/macrophages from wild-type mice trafficked to wounds with restoration of normal healing and myeloid cell function in Tlr4-deficient mice. These results define a role for myeloid-specific, MyD88-dependent TLR4 signaling in the inflammatory response following cutaneous tissue injury and suggest that MLL1 regulates TLR4 expression in wound myeloid cells.
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Affiliation(s)
- Frank M Davis
- Section of Vascular Surgery, Department of Surgery, University of Michigan, Ann Arbor, MI 48109
| | - Andrew Kimball
- Section of Vascular Surgery, Department of Surgery, University of Michigan, Ann Arbor, MI 48109
| | - Aaron denDekker
- Section of Vascular Surgery, Department of Surgery, University of Michigan, Ann Arbor, MI 48109
| | - Amrita D Joshi
- Section of Vascular Surgery, Department of Surgery, University of Michigan, Ann Arbor, MI 48109
| | - Anna E Boniakowski
- Section of Vascular Surgery, Department of Surgery, University of Michigan, Ann Arbor, MI 48109
| | - Dylan Nysz
- Section of Vascular Surgery, Department of Surgery, University of Michigan, Ann Arbor, MI 48109
| | - Ronald M Allen
- Department of Pathology, University of Michigan, Ann Arbor, MI 48109
| | - Andrea Obi
- Section of Vascular Surgery, Department of Surgery, University of Michigan, Ann Arbor, MI 48109
| | - Kanakadurga Singer
- Section of Endocrinology, Department of Pediatrics, University of Michigan, Ann Arbor, MI 48109; and
| | - Peter K Henke
- Section of Vascular Surgery, Department of Surgery, University of Michigan, Ann Arbor, MI 48109
| | - Bethany B Moore
- Department of Internal Medicine, University of Michigan, Ann Arbor, MI 48109
| | - Steven L Kunkel
- Department of Pathology, University of Michigan, Ann Arbor, MI 48109
| | - Katherine A Gallagher
- Section of Vascular Surgery, Department of Surgery, University of Michigan, Ann Arbor, MI 48109;
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Reznikov M, Andrienko D, Boychuk V, Bubnov A, Dolgov L, Dozov I, Davidson P, Gabovich A, Hegmann T, Ilchishin I, Karapinar R, Korniychuk P, Stepanchikov D, Tkachenko O, Kurioz Y, Manevich M, Negriyko A, Parka J, Pergamenshchik V, Rosenblatt C, Singer K, Terenetskaya I, Vashchenko V, Vasnetsov M, Soskin M, Wolinski T, Yaroshchuk O. Recollections of Professor Yuriy Reznikov. J Mol Liq 2018. [DOI: 10.1016/j.molliq.2018.08.127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Abstract
PURPOSE OF REVIEW As the ongoing epidemic of adult and childhood obesity grows, it puts a greater burden on individuals and the healthcare system due to increased prevalence of obesity-associated diseases. An important area that has gained much attention recently is the sex and gender difference related to obesity and associated complications. Basic science and clinical studies have now improved our understanding of obesity and have discovered adipose tissue biology to be key in metabolism. RECENT FINDINGS There is evidence related to the sex dichotomy in obesity in a variety of areas including adipocyte function, sex hormone effects, genetics, and metabolic inflammation leading to critical differences in adipose tissue biology. The sex and gender difference in adipose tissue is a factor that should be considered when studying an individuals' risk for obesity and metabolic dysfunction. This understanding is important for strategizing treatment and prevention measures.
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Affiliation(s)
- Eric Chang
- Pediatric Endocrinology, University of Michigan Medical School, Medical Professional Building, D1205 1500 E. Medical Center Drive, Ann Arbor, MI, 48109-5718, USA
| | - Mita Varghese
- Pediatric Endocrinology, University of Michigan Medical School, Medical Professional Building, D1205 1500 E. Medical Center Drive, Ann Arbor, MI, 48109-5718, USA
| | - Kanakadurga Singer
- Pediatric Endocrinology, University of Michigan Medical School, Medical Professional Building, D1205 1500 E. Medical Center Drive, Ann Arbor, MI, 48109-5718, USA.
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Stojanovska J, Lumeng CN, Griffin C, Hernando D, Hoffmann U, Haft JW, Kim KM, Burant CF, Singer K, Tsodikov A, Long BD, Romano MA, Tang PC, Yang B, Chenevert TL. Water-fat magnetic resonance imaging quantifies relative proportions of brown and white adipose tissues: ex-vivo experiments. J Med Imaging (Bellingham) 2018; 5:024007. [PMID: 30137870 PMCID: PMC6025480 DOI: 10.1117/1.jmi.5.2.024007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2018] [Accepted: 06/08/2018] [Indexed: 12/12/2022] Open
Abstract
Quantifying the amount of brown adipose tissue (BAT) within white adipose tissue (WAT) in human depots may serve as a target to combat obesity. We aimed to quantify proton density fat fraction (PDFF) of BAT and WAT in relatively pure and in mixed preparation using water–fat imaging. Three ex-vivo experiments were performed at 3 T using excised interscapular BAT and inguinal/subcutaneous WAT from mice. The first two experiments consisted of BAT and WAT in separate tubes, and the third used mixed preparation with graded quantities of BAT and WAT. To investigate the influence of partial volume on PDFF metrics, low (2.66 mm3) and high spatial resolution (0.55 mm3 acquired voxels) in two orthogonal three-dimensional sections were compared. The low-resolution acquisitions are corrected for T2* and multipeak lipid spectrum, thus considered “quantitative,” whereas the high-resolution acquisitions are not corrected but were performed to better spatially segment BAT from WAT zones. As potential BAT metrics, we quantified the average PDFF and the volume of tissue having PDFF ≤50% (VOLPDFF≤50%) based on the PDFF histogram. In the first experiment, the average PDFF of BAT was 23±6% and 21±7.6% and the average PDFF of WAT was 76±7% and 87±7% using high- and low-resolution techniques, respectively. A similar trend with excellent reproducibility in average PDFF of BAT and WAT was observed in the second experiment. In the third experiment over the four acquisitions, the BAT-dominant tube demonstrated lower PDFF (mean ± SD) of 55±2% than WAT-dominant (69±4%) and WAT-only tubes (88±4%). Estimating VOLPDFF≤50%, the BAT-dominant tube demonstrated higher volume of 0.26 cm3 than WAT-dominant (0.16 cm3) and WAT-only tubes (0.01 cm3). The presence of BAT exhibits a lower PDFF relative to WAT, thus allowing segmentation of low PDFF tissue for quantification of volume representative of BAT. Future studies will determine the clinical relevance of BAT volume within human depots.
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Affiliation(s)
- Jadranka Stojanovska
- Michigan Medicine, Division of Cardiothoracic Radiology, Department of Radiology, Ann Arbor, Michigan, United States
| | - Carey N Lumeng
- Michigan Medicine, Department of Pediatrics and Molecular Physiology, Ann Arbor, Michigan, United States
| | - Cameron Griffin
- Michigan Medicine, Division of Pediatric Endocrinology, Ann Arbor, Michigan, United States
| | - Diego Hernando
- University of Wisconsin, Wisconsin Institutes for Medical Research, Medical Physics Department, Madison, Wisconsin, United States
| | - Udo Hoffmann
- Massachusetts General Hospital, Department of Radiology, Boston, Massachusetts, United States
| | - Jonathan W Haft
- Michigan Medicine, Frankel Cardiovascular Center, Department of Cardiac Surgery, Ann Arbor, Michigan, United States
| | - Karen M Kim
- Michigan Medicine, Frankel Cardiovascular Center, Department of Cardiac Surgery, Ann Arbor, Michigan, United States
| | | | - Kanakadurga Singer
- Michigan Medicine, Division of Pediatric Endocrinology, Department of Pediatrics and Communicable Diseases, Ann Arbor, Michigan, United States
| | - Alex Tsodikov
- School of Public Health, Ann Arbor, Michigan, United States
| | - Benjamin D Long
- University of Michigan Medical School, Cardiovascular Center, Ann Arbor, Michigan, United States
| | - Matthew A Romano
- Michigan Medicine, Cardiovascular Center, Ann Arbor, Michigan, United States
| | - Paul C Tang
- Michigan Medicine, Cardiovascular Center, Ann Arbor, Michigan, United States
| | - Bo Yang
- Michigan Medicine, Cardiovascular Center, Ann Arbor, Michigan, United States
| | - Thomas L Chenevert
- Michigan Medicine, Department of Radiology-MRI, Ann Arbor, Michigan, United States
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Gállego Suárez C, Gregg BE, Watson ME, Sturza J, Bermick JR, Singer K. Preserving Future Generations of Pediatric Researchers. J Pediatr 2018; 196:4-6. [PMID: 29703371 PMCID: PMC6679652 DOI: 10.1016/j.jpeds.2018.01.061] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Accepted: 01/22/2018] [Indexed: 11/24/2022]
Affiliation(s)
- Cecilia Gállego Suárez
- Division of Pediatric Endocrinology and Metabolism, Department of Pediatrics and Communicable Diseases, University of Michigan Medical School, Ann Arbor, MI
| | - Brigid E Gregg
- Division of Pediatric Endocrinology and Metabolism, Department of Pediatrics and Communicable Diseases, University of Michigan Medical School, Ann Arbor, MI
| | - Michael E Watson
- Division of Pediatric Infectious Diseases, Department of Pediatrics and Communicable Diseases, University of Michigan Medical School, Ann Arbor, MI
| | - Julie Sturza
- Department of Pediatrics and Communicable Diseases, University of Michigan Medical School, Ann Arbor, MI
| | - Jennifer R Bermick
- Division of Neonatal-Perinatal Medicine, Department of Pediatrics and Communicable Diseases, University of Michigan Medical School, Ann Arbor, MI
| | - Kanakadurga Singer
- Division of Pediatric Endocrinology and Metabolism, Department of Pediatrics and Communicable Diseases, University of Michigan Medical School, Ann Arbor, MI.
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Griffin C, Eter L, Lanzetta N, Abrishami S, Varghese M, McKernan K, Muir L, Lane J, Lumeng CN, Singer K. TLR4, TRIF, and MyD88 are essential for myelopoiesis and CD11c + adipose tissue macrophage production in obese mice. J Biol Chem 2018; 293:8775-8786. [PMID: 29636416 DOI: 10.1074/jbc.ra117.001526] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2017] [Revised: 04/04/2018] [Indexed: 12/12/2022] Open
Abstract
Obesity-induced chronic inflammation is associated with metabolic disease. Results from mouse models utilizing a high-fat diet (HFD) have indicated that an increase in activated macrophages, including CD11c+ adipose tissue macrophages (ATMs), contributes to insulin resistance. Obesity primes myeloid cell production from hematopoietic stem cells (HSCs) and Toll-like receptor 4 (TLR4), and the downstream TIR domain-containing adapter protein-inducing interferon-β (TRIF)- and MyD88-mediated pathways regulate production of similar myeloid cells after lipopolysaccharide stimulation. However, the role of these pathways in HFD-induced myelopoiesis is unknown. We hypothesized that saturated fatty acids and HFD alter myelopoiesis by activating TLR4 pathways in HSCs, differentially producing pro-inflammatory CD11c+ myeloid cells that contribute to obesity-induced metabolic disease. Results from reciprocal bone marrow transplants (BMTs) with Tlr4-/- and WT mice indicated that TLR4 is required for HFD-induced myelopoiesis and production of CD11c+ ATMs. Experiments with homozygous knockouts of Irakm (encoding a suppressor of MyD88 inactivation) and Trif in competitive BMTs revealed that MyD88 is required for HFD expansion of granulocyte macrophage progenitors and that Trif is required for pregranulocyte macrophage progenitor expansion. A comparison of WT, Tlr4-/-, Myd88-/-, and Trif-/- mice on HFD demonstrated that TLR4 plays a role in the production of CD11c+ ATMs, and both Myd88-/- and Trif-/- mice produced fewer ATMs than WT mice. Moreover, HFD-induced TLR4 activation inhibited macrophage proliferation, leading to greater accumulation of recruited CD11c+ ATMs. Our results indicate that HFD potentiates TLR4 and both its MyD88- and TRIF-mediated downstream pathways within progenitors and adipose tissue and leads to macrophage polarization.
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Affiliation(s)
- Cameron Griffin
- From the Department of Pediatrics and Communicable Disease, University of Michigan Medical School, Ann Arbor, Michigan 48109
| | - Leila Eter
- From the Department of Pediatrics and Communicable Disease, University of Michigan Medical School, Ann Arbor, Michigan 48109
| | - Nico Lanzetta
- From the Department of Pediatrics and Communicable Disease, University of Michigan Medical School, Ann Arbor, Michigan 48109
| | - Simin Abrishami
- From the Department of Pediatrics and Communicable Disease, University of Michigan Medical School, Ann Arbor, Michigan 48109
| | - Mita Varghese
- From the Department of Pediatrics and Communicable Disease, University of Michigan Medical School, Ann Arbor, Michigan 48109
| | - Kaitlin McKernan
- From the Department of Pediatrics and Communicable Disease, University of Michigan Medical School, Ann Arbor, Michigan 48109
| | - Lindsey Muir
- From the Department of Pediatrics and Communicable Disease, University of Michigan Medical School, Ann Arbor, Michigan 48109
| | - Jamie Lane
- From the Department of Pediatrics and Communicable Disease, University of Michigan Medical School, Ann Arbor, Michigan 48109
| | - Carey N Lumeng
- From the Department of Pediatrics and Communicable Disease, University of Michigan Medical School, Ann Arbor, Michigan 48109
| | - Kanakadurga Singer
- From the Department of Pediatrics and Communicable Disease, University of Michigan Medical School, Ann Arbor, Michigan 48109
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Muir LA, Kiridena S, Griffin C, DelProposto JB, Geletka L, Martinez-Santibañez G, Zamarron BF, Lucas H, Singer K, O' Rourke RW, Lumeng CN. Frontline Science: Rapid adipose tissue expansion triggers unique proliferation and lipid accumulation profiles in adipose tissue macrophages. J Leukoc Biol 2018; 103:615-628. [PMID: 29493813 DOI: 10.1002/jlb.3hi1017-422r] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2017] [Revised: 01/04/2018] [Accepted: 01/10/2018] [Indexed: 12/22/2022] Open
Abstract
Obesity-related changes in adipose tissue leukocytes, in particular adipose tissue macrophages (ATMs) and dendritic cells (ATDCs), are implicated in metabolic inflammation, insulin resistance, and altered regulation of adipocyte function. We evaluated stromal cell and white adipose tissue (WAT) expansion dynamics with high fat diet (HFD) feeding for 3-56 days, quantifying ATMs, ATDCs, endothelial cells (ECs), and preadipocytes (PAs) in visceral epididymal WAT and subcutaneous inguinal WAT. To better understand mechanisms of the early response to obesity, we evaluated ATM proliferation and lipid accumulation. ATMs, ATDCs, and ECs increased with rapid WAT expansion, with ATMs derived primarily from a CCR2-independent resident population. WAT expansion stimulated proliferation in resident ATMs and ECs, but not CD11c+ ATMs or ATDCs. ATM proliferation was unperturbed in Csf2- and Rag1-deficient mice with WAT expansion. Additionally, ATM apoptosis decreased with WAT expansion, and proliferation and apoptosis reverted to baseline with weight loss. Adipocytes reached maximal hypertrophy at 28 days of HFD, coinciding with a plateau in resident ATM accumulation and the appearance of lipid-laden CD11c+ ATMs in visceral epididymal WAT. ATM increases were proportional to tissue expansion and adipocyte hypertrophy, supporting adipocyte-mediated regulation of resident ATMs. The appearance of lipid-laden CD11c+ ATMs at peak adipocyte size supports a role in responding to ectopic lipid accumulation within adipose tissue. In contrast, ATDCs increase independently of proliferation and may be derived from circulating precursors. These changes precede and establish the setting in which large-scale adipose tissue infiltration of CD11c+ ATMs, inflammation, and adipose tissue dysfunction contributes to insulin resistance.
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Affiliation(s)
- Lindsey A Muir
- Department of Pediatrics and Communicable Diseases, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Samadhi Kiridena
- College of Literature Science and the Arts, University of Michigan, Ann Arbor, Michigan, USA
| | - Cameron Griffin
- Department of Pediatrics and Communicable Diseases, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Jennifer B DelProposto
- Department of Pediatrics and Communicable Diseases, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Lynn Geletka
- Department of Pediatrics and Communicable Diseases, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Gabriel Martinez-Santibañez
- Cellular and Molecular Biology Graduate Program, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Brian F Zamarron
- Graduate Program in Immunology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Hannah Lucas
- College of Literature Science and the Arts, University of Michigan, Ann Arbor, Michigan, USA
| | - Kanakadurga Singer
- Department of Pediatrics and Communicable Diseases, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Robert W O' Rourke
- Department of Surgery, University of Michigan Medical School, Ann Arbor, Michigan, USA.,Department of Surgery, Ann Arbor Veterans Administration Hospital, Ann Arbor, Michigan, USA
| | - Carey N Lumeng
- Department of Pediatrics and Communicable Diseases, University of Michigan Medical School, Ann Arbor, Michigan, USA.,Cellular and Molecular Biology Graduate Program, University of Michigan Medical School, Ann Arbor, Michigan, USA.,Graduate Program in Immunology, University of Michigan Medical School, Ann Arbor, Michigan, USA
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Peterson LS, Gállego Suárez C, Segaloff HE, Griffin C, Martin ET, Odetola FO, Singer K. Outcomes and Resource Use Among Overweight and Obese Children With Sepsis in the Pediatric Intensive Care Unit. J Intensive Care Med 2018; 35:472-477. [PMID: 29471722 DOI: 10.1177/0885066618760541] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
OBJECTIVE To evaluate the effect of overweight and obesity on outcomes and resource use among patients with sepsis in the pediatric intensive care unit (PICU). DESIGN Retrospective analysis of clinical characteristics, resource use, and mortality among children 0 to 20 years of age admitted to the C.S. MottChildren's Hospital PICU (University of Michigan) between January 2009 and December 2015, with a diagnostic code for sepsis at admission (based on International Classification of Diseases, Ninth Revision-Clinical Modification codes) and with weight and height measurements at PICU admission. MEASUREMENTS AND MAIN RESULTS A total of 454 participants met the inclusion criteria. Seventy-six were categorized as underweight (body mass index [BMI] percentile <5th) and were excluded, which left a final sample size of 378 participants. Children with a BMI >5th and <85th percentiles for age were categorized as normal weight and those with a BMI >85th percentile as overweight/obese. After descriptive and bivariate analyses, multivariate regression methods were used to assess the independent effect of obesity status on mortality and the use of PICU technology after adjustment for patient age and illness severity at admission. Of the 378 patients studied, 41.3% were overweight/obese. There was no difference in microbiologic etiology of sepsis (P = .36), median PICU length of stay in days (5.4 vs 5.6; P = .61), or PICU mortality (6.4% vs 7.2%; P = .76) by weight status. The use of specialized PICU technology including extracorporeal membrane oxygenation (odds ratio [OR]: 2.77, 95% confidence interval [CI]:1.13-6.79) and continuous renal replacement therapy (OR: 4.58, 95% CI: 1.16-18.0) was higher among overweight/obese patients, compared with normal weight patients. CONCLUSIONS Although PICU mortality and length of stay were similar for obese-overweight patients and normal weight critically ill children with sepsis, there was significantly higher use of specialized organ-supportive technology among obese patients, likely indicating higher occurrence of multiple organ dysfunction.
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Affiliation(s)
- Laura S Peterson
- Department of Pediatrics and Communicable Diseases, University of Michigan, Ann Arbor, MI, USA
| | - Cecilia Gállego Suárez
- Division of Pediatric Endocrinology and Metabolism, Department of Pediatrics and Communicable Diseases, University of Michigan, Ann Arbor, MI, USA
| | - Hannah E Segaloff
- Department of Epidemiology, School of Public Health, University of Michigan, Ann Arbor, MI, USA
| | - Cameron Griffin
- Division of Pediatric Endocrinology and Metabolism, Department of Pediatrics and Communicable Diseases, University of Michigan, Ann Arbor, MI, USA
| | - Emily T Martin
- Department of Epidemiology, School of Public Health, University of Michigan, Ann Arbor, MI, USA
| | - Folafoluwa O Odetola
- Division of Critical Care Medicine, Department of Pediatrics and Communicable Diseases, University of Michigan, Ann Arbor, MI, USA
| | - Kanakadurga Singer
- Division of Pediatric Endocrinology and Metabolism, Department of Pediatrics and Communicable Diseases, University of Michigan, Ann Arbor, MI, USA
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