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O'Brien KA, Gu W, Houck JA, Holzner LMW, Yung HW, Armstrong JL, Sowton AP, Baxter R, Darwin PM, Toledo-Jaldin L, Lazo-Vega L, Moreno-Aramayo AE, Miranda-Garrido V, Shortt JA, Matarazzo CJ, Yasini H, Burton GJ, Moore LG, Simonson TS, Murray AJ, Julian CG. Genomic Selection Signals in Andean Highlanders Reveal Adaptive Placental Metabolic Phenotypes That Are Disrupted in Preeclampsia. Hypertension 2024; 81:319-329. [PMID: 38018457 PMCID: PMC10841680 DOI: 10.1161/hypertensionaha.123.21748] [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] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Accepted: 10/24/2023] [Indexed: 11/30/2023]
Abstract
BACKGROUND The chronic hypoxia of high-altitude residence poses challenges for tissue oxygen supply and metabolism. Exposure to high altitude during pregnancy increases the incidence of hypertensive disorders of pregnancy and fetal growth restriction and alters placental metabolism. High-altitude ancestry protects against altitude-associated fetal growth restriction, indicating hypoxia tolerance that is genetic in nature. Yet, not all babies are protected and placental pathologies associated with fetal growth restriction occur in some Andean highlanders. METHODS We examined placental metabolic function in 79 Andeans (18-45 years; 39 preeclamptic and 40 normotensive) living in La Paz, Bolivia (3600-4100 m) delivered by unlabored Cesarean section. Using a selection-nominated approach, we examined links between putatively adaptive genetic variation and phenotypes related to oxygen delivery or placental metabolism. RESULTS Mitochondrial oxidative capacity was associated with fetal oxygen delivery in normotensive but not preeclamptic placenta and was also suppressed in term preeclamptic pregnancy. Maternal haplotypes in or within 200 kb of selection-nominated genes were associated with lower placental mitochondrial respiratory capacity (PTPRD [protein tyrosine phosphatase receptor-δ]), lower maternal plasma erythropoietin (CPT2 [carnitine palmitoyl transferase 2], proopiomelanocortin, and DNMT3 [DNA methyltransferase 3]), and lower VEGF (vascular endothelial growth factor) in umbilical venous plasma (TBX5 [T-box transcription factor 5]). A fetal haplotype within 200 kb of CPT2 was associated with increased placental mitochondrial complex II capacity, placental nitrotyrosine, and GLUT4 (glucose transporter type 4) protein expression. CONCLUSIONS Our findings reveal novel associations between putatively adaptive gene regions and phenotypes linked to oxygen delivery and placental metabolic function in highland Andeans, suggesting that such effects may be of genetic origin. Our findings also demonstrate maladaptive metabolic mechanisms in the context of preeclampsia, including dysregulation of placental oxygen consumption.
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Affiliation(s)
- Katie A O'Brien
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom (K.A.O., L.M.W.H., H.W.Y., J.L.A., A.P.S., R.B., P.M.D., G.J.B., A.J.M.)
- Department of Medicine, Division of Pulmonary, Critical Care, and Sleep Medicine (K.A.O., W.G., T.S.S.), University of California San Diego, La Jolla, CA
- Department of Biomedical Informatics (K.A.O., J.A.H., J.A.S., C.J.M., H.Y., C.G.J.), University of Colorado School of Medicine, Aurora, CO
| | - Wanjun Gu
- Department of Medicine, Division of Pulmonary, Critical Care, and Sleep Medicine (K.A.O., W.G., T.S.S.), University of California San Diego, La Jolla, CA
- Herbert Wertheim School of Public Health and Longevity Sciences (W.G.), University of California San Diego, La Jolla, CA
| | - Julie A Houck
- Department of Biomedical Informatics (K.A.O., J.A.H., J.A.S., C.J.M., H.Y., C.G.J.), University of Colorado School of Medicine, Aurora, CO
- Department of Obstetrics and Gynecology, Division of Reproductive Sciences (J.A.H., L.G.M.), University of Colorado School of Medicine, Aurora, CO
| | - Lorenz M W Holzner
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom (K.A.O., L.M.W.H., H.W.Y., J.L.A., A.P.S., R.B., P.M.D., G.J.B., A.J.M.)
| | - Hong Wa Yung
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom (K.A.O., L.M.W.H., H.W.Y., J.L.A., A.P.S., R.B., P.M.D., G.J.B., A.J.M.)
| | - Jenna L Armstrong
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom (K.A.O., L.M.W.H., H.W.Y., J.L.A., A.P.S., R.B., P.M.D., G.J.B., A.J.M.)
| | - Alice P Sowton
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom (K.A.O., L.M.W.H., H.W.Y., J.L.A., A.P.S., R.B., P.M.D., G.J.B., A.J.M.)
| | - Ruby Baxter
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom (K.A.O., L.M.W.H., H.W.Y., J.L.A., A.P.S., R.B., P.M.D., G.J.B., A.J.M.)
| | - Paula M Darwin
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom (K.A.O., L.M.W.H., H.W.Y., J.L.A., A.P.S., R.B., P.M.D., G.J.B., A.J.M.)
| | - Lilian Toledo-Jaldin
- Department of Obstetrics, Hospital Materno-Infantil, La Paz, Bolivia (L.T.-J., L.L.-V., A.E.M.-M., V.M.-G.)
| | - Litzi Lazo-Vega
- Department of Obstetrics, Hospital Materno-Infantil, La Paz, Bolivia (L.T.-J., L.L.-V., A.E.M.-M., V.M.-G.)
| | - Any Elena Moreno-Aramayo
- Department of Obstetrics, Hospital Materno-Infantil, La Paz, Bolivia (L.T.-J., L.L.-V., A.E.M.-M., V.M.-G.)
| | - Valquiria Miranda-Garrido
- Department of Obstetrics, Hospital Materno-Infantil, La Paz, Bolivia (L.T.-J., L.L.-V., A.E.M.-M., V.M.-G.)
| | - Jonathan A Shortt
- Department of Biomedical Informatics (K.A.O., J.A.H., J.A.S., C.J.M., H.Y., C.G.J.), University of Colorado School of Medicine, Aurora, CO
| | - Christopher J Matarazzo
- Department of Biomedical Informatics (K.A.O., J.A.H., J.A.S., C.J.M., H.Y., C.G.J.), University of Colorado School of Medicine, Aurora, CO
| | - Hussna Yasini
- Department of Biomedical Informatics (K.A.O., J.A.H., J.A.S., C.J.M., H.Y., C.G.J.), University of Colorado School of Medicine, Aurora, CO
| | - Graham J Burton
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom (K.A.O., L.M.W.H., H.W.Y., J.L.A., A.P.S., R.B., P.M.D., G.J.B., A.J.M.)
| | - Lorna G Moore
- Department of Obstetrics and Gynecology, Division of Reproductive Sciences (J.A.H., L.G.M.), University of Colorado School of Medicine, Aurora, CO
| | - Tatum S Simonson
- Department of Medicine, Division of Pulmonary, Critical Care, and Sleep Medicine (K.A.O., W.G., T.S.S.), University of California San Diego, La Jolla, CA
| | - Andrew J Murray
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom (K.A.O., L.M.W.H., H.W.Y., J.L.A., A.P.S., R.B., P.M.D., G.J.B., A.J.M.)
| | - Colleen G Julian
- Department of Biomedical Informatics (K.A.O., J.A.H., J.A.S., C.J.M., H.Y., C.G.J.), University of Colorado School of Medicine, Aurora, CO
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Julian CG, Houck JA, Fallahi S, Lazo-Vega L, Matarazzo CJ, Diamond B, Miranda-Garrido V, Krause BJ, Moore LG, Shortt JA, Toledo-Jaldin L, Lorca RA. Altered placental ion channel gene expression in preeclamptic high-altitude pregnancies. Physiol Genomics 2023; 55:357-367. [PMID: 37458464 PMCID: PMC10642922 DOI: 10.1152/physiolgenomics.00013.2023] [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] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 06/12/2023] [Accepted: 07/06/2023] [Indexed: 08/12/2023] Open
Abstract
High-altitude (>2,500 m) residence increases the risk of pregnancy vascular disorders such as fetal growth restriction and preeclampsia, each characterized by impaired placental function. Genetic attributes of highland ancestry confer relative protection against vascular disorders of pregnancy at high altitudes. Although ion channels have been implicated in placental function regulation, neither their expression in high-altitude placentas nor their relationship to high-altitude preeclampsia has been determined. Here, we measured the expression of 26 ion-channel genes in placentas from preeclampsia cases and normotensive controls in La Paz, Bolivia (3,850 m). In addition, we correlated gene transcription to maternal and infant ancestry proportions. Gene expression was assessed by PCR, genetic ancestry evaluated by ADMIXTURE, and ion channel proteins localized by immunofluorescence. In preeclamptic placentas, 11 genes were downregulated (ABCC9, ATP2A2, CACNA1C, KCNE1, KCNJ8, KCNK3, KCNMA1, KCNQ1, KCNQ4, PKD2, and TRPV6) and two were upregulated (KCNQ3 and SCNN1G). KCNE1 expression was positively correlated with high-altitude Amerindian ancestry and negatively correlated with non-high altitude. SCNN1G was negatively correlated with African ancestry, despite minimal African admixture. Most ion channels were localized in syncytiotrophoblasts (Cav1.2, TRPP2, TRPV6, and Kv7.1), whereas expression of Kv7.4 was primarily in microvillous membranes, Kir6.1 in chorionic plate and fetal vessels, and MinK in stromal cells. Our findings suggest a role for differential placental ion channel expression in the development of preeclampsia. Functional studies are needed to determine processes affected by these ion channels in the placenta and whether therapies directed at modulating their activity could influence the onset or severity of preeclampsia.
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Affiliation(s)
- Colleen G Julian
- Department of Biomedical Informatics, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States
- Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States
| | - Julie A Houck
- Department of Biomedical Informatics, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States
- Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States
- Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States
| | - Sahand Fallahi
- Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States
| | - Litzi Lazo-Vega
- Department of Obstetrics and Gynecology, Hospital Materno-Infantil, La Paz, Bolivia
| | - Christopher J Matarazzo
- Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States
| | - Breea Diamond
- Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States
| | | | - Bernardo J Krause
- Instituto de Ciencias de la Salud, Universidad de O'Higgins, Rancagua, Chile
| | - Lorna G Moore
- Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States
| | - Jonathan A Shortt
- Department of Biomedical Informatics, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States
| | - Lilian Toledo-Jaldin
- Department of Obstetrics and Gynecology, Hospital Materno-Infantil, La Paz, Bolivia
| | - Ramón A Lorca
- Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States
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Fallahi S, Houck JA, Euser AG, Julian CG, Moore LG, Lorca RA. High altitude differentially modulates potassium channel-evoked vasodilatation in pregnant human myometrial arteries. J Physiol 2022; 600:5353-5364. [PMID: 36286320 PMCID: PMC9772154 DOI: 10.1113/jp283741] [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] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Accepted: 10/12/2022] [Indexed: 01/05/2023] Open
Abstract
High-altitude (>2500 m or 8200 ft) residence reduces uterine artery blood flow during pregnancy, contributing to an increased incidence of preeclampsia and intrauterine growth restriction. However, not all pregnancies are affected by the chronic hypoxic conditions of high-altitude residence. K+ channels play important roles in the uterine vascular adaptation to pregnancy, promoting a reduction in myogenic tone and an increase in blood flow. We hypothesized that, in pregnancies with normal fetal growth at high altitude, K+ channel-dependent vasodilatation of myometrial arteries is increased compared to those from healthy pregnant women at a lower altitude (∼1700 m). Using pharmacological modulation of two K+ channels, ATP-sensitive (KATP ) and large-conductance Ca2+ -activated (BKCa ) K+ channels, we assessed the vasodilatation of myometrial arteries from appropriate for gestational age (AGA) pregnancies in women living at high or low altitudes. In addition, we evaluated the localization of these channels in the myometrial arteries using immunofluorescence. Our results showed an endothelium-dependent increase in KATP -dependent vasodilatation in myometrial arteries from high versus low altitude, whereas vasodilatation induced by BKCa activation was reduced in these vessels. Additionally, KATP channel co-localization with endothelial markers was reduced in the high-altitude myometrial arteries, which suggested that the functional increase in KATP activity may be by mechanisms other than regulation of channel localization. These observations highlight an important contribution of K+ channels to the human uterine vascular adaptation to pregnancy at high altitude serving to maintain normal fetal growth under conditions of chronic hypoxia. KEY POINTS: High-altitude (>2500 m or 8200 ft) residence reduces uterine blood flow during pregnancy and fetal growth. Animal models of high altitude/chronic hypoxia suggest that these reductions are partially due to reduced vascular K+. channel responses, such as those elicited by large conductance Ca2+ -activated (BKCa ) and ATP-sensitive (KATP ) K+ channel activation. We found that women residing at high versus low altitude during pregnancy showed diminished myometrial artery vasodilatory responses to endothelium-independent BKCa channel activation but greater responses to endothelium-dependent KATP channel activation. Our observations indicate that KATP channels play an adaptive role in maintaining myometrial artery vasodilator sensitivity under chronic hypoxic conditions during pregnancy. Thus, KATP channels represent potential therapeutic targets for augmenting uteroplacental blood flow and, in turn, preserving fetal growth in cases of uteroplacental hypoperfusion.
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Affiliation(s)
- Sahand Fallahi
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Denver-Anschutz Medical Campus, Aurora, CO 80045
| | - Julie A. Houck
- Department of Biomedical Informatics, University of Colorado Denver-Anschutz Medical Campus, Aurora, CO 80045
| | - Anna G. Euser
- Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, University of Colorado Denver-Anschutz Medical Campus, Aurora, CO 80045
| | - Colleen G. Julian
- Department of Biomedical Informatics, University of Colorado Denver-Anschutz Medical Campus, Aurora, CO 80045
| | - Lorna G. Moore
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Denver-Anschutz Medical Campus, Aurora, CO 80045
| | - Ramón A. Lorca
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Denver-Anschutz Medical Campus, Aurora, CO 80045
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Heath-Freudenthal A, Toledo-Jaldin L, von Alvensleben I, Lazo-Vega L, Mizutani R, Stalker M, Yasini H, Mendizabal F, Madera JD, Mundo W, Castro-Monrroy M, Houck JA, Moreno-Aramayo A, Miranda-Garrido V, Su EJ, Giussani DA, Abman SH, Moore LG, Julian CG. Vascular Disorders of Pregnancy Increase Susceptibility to Neonatal Pulmonary Hypertension in High-Altitude Populations. Hypertension 2022; 79:1286-1296. [PMID: 35437031 PMCID: PMC9098686 DOI: 10.1161/hypertensionaha.122.19078] [Citation(s) in RCA: 8] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Accepted: 03/29/2022] [Indexed: 11/16/2022]
Abstract
BACKGROUND Preeclampsia and fetal growth restriction increase cardiopulmonary disease risk for affected offspring and occur more frequently at high-altitude (≥2500 m). Retrospective studies indicate that birth to a preeclampsia woman at high altitude increases the risk of pulmonary hypertension (PH) in later life. This prospective study asked whether preeclampsia with or without fetal growth restriction exaggerated fetal hypoxia and impaired angiogenesis in the fetal lung, leading to neonatal cardiopulmonary circulation abnormalities and neonatal or infantile PH. METHODS AND RESULTS We studied 79 maternal-infant pairs (39 preeclampsia, 40 controls) in Bolivia (3600-4100 m). Cord blood erythropoietin, hemoglobin, and umbilical artery and venous blood gases were measured as indices of fetal hypoxia. Maternal and cord plasma levels of angiogenic (VEGF [vascular endothelial growth factor]) and antiangiogenic (sFlt1 [soluble fms-like tyrosine kinase]) factors were determined. Postnatal echocardiography (1 week and 6-9 months) assessed pulmonary hemodynamics and PH. Preeclampsia augmented fetal hypoxia and increased the risk of PH in the neonate but not later in infancy. Pulmonary abnormalities were confined to preeclampsia cases with fetal growth restriction. Maternal and fetal plasma sFlt1 levels were higher in preeclampsia than controls and positively associated with PH. CONCLUSIONS The effect of preeclampsia with fetal growth restriction to increase fetal hypoxia and sFlt1 levels may impede normal development of the pulmonary circulation at high altitude, leading to adverse neonatal pulmonary vascular outcomes. Our observations highlight important temporal windows for the prevention of pulmonary vascular disease among babies born to highland residents or those with exaggerated hypoxia in utero or newborn life.
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Affiliation(s)
| | | | | | | | | | | | - Hussna Yasini
- College of Liberal Arts and Sciences, University of Colorado Denver, Denver, Colorado
| | | | - Jesus Dorado Madera
- College of Liberal Arts and Sciences, University of Colorado Denver, Denver, Colorado
| | - William Mundo
- University of Colorado School of Medicine, Aurora, Colorado
| | | | - Julie A. Houck
- Department of Medicine, University of Colorado School of Medicine, Aurora, Colorado
| | | | | | - Emily J. Su
- Departments of Obstetrics and Gynecology, University of Colorado School of Medicine, Aurora, Colorado
| | - Dino A. Giussani
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom
| | - Steven H. Abman
- Department of Pediatrics, University of Colorado School of Medicine, Aurora, Colorado
| | - Lorna G. Moore
- Departments of Obstetrics and Gynecology, University of Colorado School of Medicine, Aurora, Colorado
| | - Colleen G. Julian
- Department of Medicine, University of Colorado School of Medicine, Aurora, Colorado
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Scalzo RL, Foright RM, Hull SE, Knaub LA, Johnson-Murguia S, Kinanee F, Kaplan J, Houck JA, Johnson G, Sharp RR, Gillen AE, Jones KL, Zhang AMY, Johnson JD, MacLean PS, Reusch JEB, Wright-Hobart S, Wellberg EA. Breast Cancer Endocrine Therapy Promotes Weight Gain With Distinct Adipose Tissue Effects in Lean and Obese Female Mice. Endocrinology 2021; 162:bqab174. [PMID: 34410380 PMCID: PMC8455348 DOI: 10.1210/endocr/bqab174] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [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: 05/24/2021] [Indexed: 12/19/2022]
Abstract
Breast cancer survivors treated with tamoxifen and aromatase inhibitors report weight gain and have an elevated risk of type 2 diabetes, especially if they have obesity. These patient experiences are inconsistent with, preclinical studies using high doses of tamoxifen which reported acute weight loss. We investigated the impact of breast cancer endocrine therapies in a preclinical model of obesity and in a small group of breast adipose tissue samples from women taking tamoxifen to understand the clinical findings. Mature female mice were housed at thermoneutrality and fed either a low-fat/low-sucrose (LFLS) or a high-fat/high-sucrose (HFHS) diet. Consistent with the high expression of Esr1 observed in mesenchymal stem cells from adipose tissue, endocrine therapy was associated with adipose accumulation and more preadipocytes compared with estrogen-treated control mice but resulted in fewer adipocyte progenitors only in the context of HFHS. Analysis of subcutaneous adipose stromal cells revealed diet- and treatment-dependent effects of endocrine therapies on various cell types and genes, illustrating the complexity of adipose tissue estrogen receptor signaling. Breast cancer therapies supported adipocyte hypertrophy and associated with hepatic steatosis, hyperinsulinemia, and glucose intolerance, particularly in obese females. Current tamoxifen use associated with larger breast adipocyte diameter only in women with obesity. Our translational studies suggest that endocrine therapies may disrupt adipocyte progenitors and support adipocyte hypertrophy, potentially leading to ectopic lipid deposition that may be linked to a greater type 2 diabetes risk. Monitoring glucose tolerance and potential interventions that target insulin action should be considered for some women receiving life-saving endocrine therapies for breast cancer.
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Affiliation(s)
- Rebecca L Scalzo
- Division of Endocrinology, Metabolism & Diabetes, Department of Medicine; University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
- Center for Women’s Health Research; University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
- Rocky Mountain Regional VA Medical Center, Aurora, CO 80045, USA
| | - Rebecca M Foright
- Department of Anatomy and Cell Biology, University of Kansas Medical Center, Kansas City, KS 66160, USA
| | - Sara E Hull
- Division of Endocrinology, Metabolism & Diabetes, Department of Medicine; University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Leslie A Knaub
- Division of Endocrinology, Metabolism & Diabetes, Department of Medicine; University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Stevi Johnson-Murguia
- Department of Pathology, University of Oklahoma Health Sciences Center, Stephenson Cancer Center, Harold Hamm Diabetes Research Center, Oklahoma City, OK 73104, USA
| | - Fotobari Kinanee
- Department of Pathology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Jeffrey Kaplan
- Department of Pathology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Julie A Houck
- Division of Endocrinology, Metabolism & Diabetes, Department of Medicine; University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Ginger Johnson
- Division of Endocrinology, Metabolism & Diabetes, Department of Medicine; University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Rachel R Sharp
- Department of Cell Biology, University of Oklahoma Health Sciences Center, Stephenson Cancer Center, Harold Hamm Diabetes Research Center, Oklahoma City, OK 73104, USA
| | - Austin E Gillen
- Division of Hematology, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Kenneth L Jones
- Department of Cell Biology, University of Oklahoma Health Sciences Center, Stephenson Cancer Center, Harold Hamm Diabetes Research Center, Oklahoma City, OK 73104, USA
| | - Anni M Y Zhang
- Diabetes Research Group, Life Sciences Institute, Department of Cellular and Physiological Sciences, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
| | - James D Johnson
- Diabetes Research Group, Life Sciences Institute, Department of Cellular and Physiological Sciences, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
| | - Paul S MacLean
- Division of Endocrinology, Metabolism & Diabetes, Department of Medicine; University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
- Center for Women’s Health Research; University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
- Department of Pathology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Jane E B Reusch
- Division of Endocrinology, Metabolism & Diabetes, Department of Medicine; University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
- Center for Women’s Health Research; University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
- Rocky Mountain Regional VA Medical Center, Aurora, CO 80045, USA
| | - Sabrina Wright-Hobart
- Department of Pathology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Elizabeth A Wellberg
- Center for Women’s Health Research; University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
- Department of Pathology, University of Oklahoma Health Sciences Center, Stephenson Cancer Center, Harold Hamm Diabetes Research Center, Oklahoma City, OK 73104, USA
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Presby DM, Rudolph MC, Sherk VD, Jackman MR, Foright RM, Jones KL, Houck JA, Johnson GC, Higgins JA, Neufer PD, Eckel RH, MacLean PS. Lipoprotein Lipase Overexpression in Skeletal Muscle Attenuates Weight Regain by Potentiating Energy Expenditure. Diabetes 2021; 70:867-877. [PMID: 33536195 PMCID: PMC7980196 DOI: 10.2337/db20-0763] [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] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Accepted: 01/27/2021] [Indexed: 11/13/2022]
Abstract
Moderate weight loss improves numerous risk factors for cardiometabolic disease; however, long-term weight loss maintenance (WLM) is often thwarted by metabolic adaptations that suppress energy expenditure and facilitate weight regain. Skeletal muscle has a prominent role in energy homeostasis; therefore, we investigated the effect of WLM and weight regain on skeletal muscle in rodents. In skeletal muscle of obesity-prone rats, WLM reduced fat oxidative capacity and downregulated genes involved in fat metabolism. Interestingly, even after weight was regained, genes involved in fat metabolism were also reduced. We then subjected mice with skeletal muscle lipoprotein lipase overexpression (mCK-hLPL), which augments fat metabolism, to WLM and weight regain and found that mCK-hLPL attenuates weight regain by potentiating energy expenditure. Irrespective of genotype, weight regain suppressed dietary fat oxidation and downregulated genes involved in fat metabolism in skeletal muscle. However, mCK-hLPL mice oxidized more fat throughout weight regain and had greater expression of genes involved in fat metabolism and lower expression of genes involved in carbohydrate metabolism during WLM and regain. In summary, these results suggest that skeletal muscle fat oxidation is reduced during WLM and regain, and therapies that improve skeletal muscle fat metabolism may attenuate rapid weight regain.
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Affiliation(s)
- David M Presby
- Section on Integrative Physiology and Metabolism, Joslin Diabetes Center, Harvard Medical School, Boston, MA
| | - Michael C Rudolph
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK
| | - Vanessa D Sherk
- Division of Endocrinology, Metabolism and Diabetes, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO
| | - Matthew R Jackman
- Section on Integrative Physiology and Metabolism, Joslin Diabetes Center, Harvard Medical School, Boston, MA
| | - Rebecca M Foright
- Department of Anatomy and Cell Biology, University of Kansas Medical Center, Kansas City, KS
| | - Kenneth L Jones
- Department of Pediatrics, University of Colorado Denver Anschutz Medical Campus, Aurora, CO
| | - Julie A Houck
- Division of Endocrinology, Metabolism and Diabetes, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO
| | - Ginger C Johnson
- Division of Endocrinology, Metabolism and Diabetes, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO
| | - Janine A Higgins
- Department of Pediatrics, University of Colorado Denver Anschutz Medical Campus, Aurora, CO
| | - P Darrell Neufer
- East Carolina Diabetes and Obesity Institute and the Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, NC
| | - Robert H Eckel
- Division of Endocrinology, Metabolism and Diabetes, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO
| | - Paul S MacLean
- Division of Endocrinology, Metabolism and Diabetes, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO
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Mundo W, Wolfson G, Moore LG, Houck JA, Park D, Julian CG. Hypoxia-induced inhibition of mTORC1 activity in the developing lung: a possible mechanism for the developmental programming of pulmonary hypertension. Am J Physiol Heart Circ Physiol 2021; 320:H980-H990. [PMID: 33416457 PMCID: PMC7988757 DOI: 10.1152/ajpheart.00520.2020] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [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: 06/25/2020] [Revised: 12/14/2020] [Accepted: 01/04/2021] [Indexed: 11/22/2022]
Abstract
Perinatal hypoxia induces permanent structural and functional changes in the lung and its pulmonary circulation that are associated with the development of pulmonary hypertension (PH) in later life. The mechanistic target of the rapamycin (mTOR) pathway is vital for fetal lung development and is implicated in hypoxia-associated PH, yet its involvement in the developmental programming of PH remains unclear. Pregnant C57/BL6 dams were placed in hyperbaric (760 mmHg) or hypobaric chambers during gestation (505 mmHg, day 15 through postnatal day 4) or from weaning through adulthood (420 mmHg, postnatal day 21 through 8 wk). Pulmonary hemodynamics and right ventricular systolic pressure (RVSP) were measured at 8 wk. mTOR pathway proteins were assessed in fetal (day 18.5) and adult lung (8 wk). Perinatal hypoxia induced PH during adulthood, even in the absence of a sustained secondary hypoxic exposure, as indicated by reduced pulmonary artery acceleration time (PAAT) and peak flow velocity through the pulmonary valve, as well as greater RVSP, right ventricular (RV) wall thickness, and RV/left ventricular (LV) weight. Such effects were independent of increased blood viscosity. In fetal lung homogenates, hypoxia reduced the expression of critical downstream mTOR targets, most prominently total and phosphorylated translation repressor protein (4EBP1), as well as vascular endothelial growth factor, a central regulator of angiogenesis in the fetal lung. In contrast, adult offspring of hypoxic dams tended to have elevated p4EBP1 compared with controls. Our data suggest that inhibition of mTORC1 activity in the fetal lung as a result of gestational hypoxia may interrupt pulmonary vascular development and thereby contribute to the developmental programming of PH.NEW & NOTEWORTHY We describe the first study to evaluate a role for the mTOR pathway in the developmental programming of pulmonary hypertension. Our findings suggest that gestational hypoxia impairs mTORC1 activation in the fetal lung and may impede pulmonary vascular development, setting the stage for pulmonary vascular disease in later life.
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Affiliation(s)
- William Mundo
- School of Medicine, University of Colorado Denver, Aurora, Colorado
| | - Gabriel Wolfson
- Division of Biomedical Informatics and Personalized Medicine, Department of Medicine, University of Colorado Denver, Aurora, Colorado
| | - Lorna G Moore
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado
| | - Julie A Houck
- Division of Biomedical Informatics and Personalized Medicine, Department of Medicine, University of Colorado Denver, Aurora, Colorado
| | - Do Park
- School of Medicine, University of Colorado Denver, Aurora, Colorado
| | - Colleen G Julian
- Division of Biomedical Informatics and Personalized Medicine, Department of Medicine, University of Colorado Denver, Aurora, Colorado
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Lorca RA, Houck JA, Laurent LC, Matarazzo CJ, Baker K, Horii M, Nelson KK, Bales ES, Euser AG, Parast MM, Moore LG, Julian CG. High altitude regulates the expression of AMPK pathways in human placenta. Placenta 2021; 104:267-276. [PMID: 33472134 DOI: 10.1016/j.placenta.2021.01.010] [Citation(s) in RCA: 7] [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: 11/16/2020] [Revised: 12/29/2020] [Accepted: 01/08/2021] [Indexed: 12/24/2022]
Abstract
INTRODUCTION High-altitude (>2500 m) residence augments the risk of intrauterine growth restriction (IUGR) and preeclampsia likely due, in part, to uteroplacental hypoperfusion. Previous genomic and transcriptomic studies in humans and functional studies in mice and humans suggest a role for AMP-activated protein kinase (AMPK) pathway in protecting against hypoxia-associated IUGR. AMPK is a metabolic sensor activated by hypoxia that is ubiquitously expressed in vascular beds and placenta. METHODS We measured gene expression and protein levels of AMPK and its upstream regulators and downstream targets in human placentas from high (>2500 m) vs. moderate (~1700 m) and low (~100 m) altitude. RESULTS We found that phosphorylated AMPK protein levels and its downstream target TSC2 were increased in placentas from high and moderate vs. low altitude, whereas the phosphorylated form of the downstream target translation repressor protein 4E-BP1 was increased in high compared to moderate as well as low altitude placentas. Mean birth weights progressively fell with increasing altitude but no infants, by study design, were clinically growth-restricted. Gene expression analysis showed moderate increases in PRKAG2, encoding the AMPK γ2 subunit, and mechanistic target of rapamycin, MTOR, expression. DISCUSSION These results highlight a differential regulation of placental AMPK pathway activation in women residing at low, moderate or high altitude during pregnancy, suggesting AMPK may be serving as a metabolic regulator for integrating hypoxic stimuli with placental function.
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Affiliation(s)
- Ramón A Lorca
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Denver-Anschutz Medical Campus, Aurora, CO, 80045, USA.
| | - Julie A Houck
- Division of Biomedical Informatics and Personalized Medicine, Department of Medicine, University of Colorado Denver-Anschutz Medical Campus, Aurora, CO, 80045, USA
| | - Louise C Laurent
- Department of Reproductive Medicine, University of California San Diego, La Jolla, 92093, USA
| | - Christopher J Matarazzo
- Division of Biomedical Informatics and Personalized Medicine, Department of Medicine, University of Colorado Denver-Anschutz Medical Campus, Aurora, CO, 80045, USA
| | - Kori Baker
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Denver-Anschutz Medical Campus, Aurora, CO, 80045, USA
| | - Mariko Horii
- Department of Pathology, University of California San Diego, La Jolla, 92093, USA
| | - Katharine K Nelson
- Department of Pathology, University of California San Diego, La Jolla, 92093, USA
| | - Elise S Bales
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Denver-Anschutz Medical Campus, Aurora, CO, 80045, USA
| | - Anna G Euser
- Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, University of Colorado Denver-Anschutz Medical Campus, Aurora, CO, 80045, USA
| | - Mana M Parast
- Department of Pathology, University of California San Diego, La Jolla, 92093, USA
| | - Lorna G Moore
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Denver-Anschutz Medical Campus, Aurora, CO, 80045, USA
| | - Colleen G Julian
- Division of Biomedical Informatics and Personalized Medicine, Department of Medicine, University of Colorado Denver-Anschutz Medical Campus, Aurora, CO, 80045, USA
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Lane SL, Houck JA, Doyle AS, Bales ES, Lorca RA, Julian CG, Moore LG. AMP-activated protein kinase activator AICAR attenuates hypoxia-induced murine fetal growth restriction in part by improving uterine artery blood flow. J Physiol 2020; 598:4093-4105. [PMID: 32592403 DOI: 10.1113/jp279341] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Accepted: 06/24/2020] [Indexed: 12/20/2022] Open
Abstract
KEY POINTS Pregnancy at high altitude is associated with a greater incidence of fetal growth restriction due, in part, to lesser uterine artery blood flow. AMP-activated protein kinase (AMPK) activation vasodilates arteries and may increase uterine artery blood flow. In this study, pharmacological activation of AMPK by the drug AICAR improved fetal growth and elevated uterine artery blood flow. These results suggest that AMPK activation is a potential strategy for improving fetal growth and raising uterine artery blood flow in pregnancy, which may be important in pregnancy disorders characterized by uteroplacental ischaemia and/or fetal hypoxia. ABSTRACT Uteroplacental hypoxia is associated with pregnancy disorders such as intrauterine growth restriction and preeclampsia, which are characterized by uteroplacental ischaemia and/or fetal hypoxia. Activation of AMP-activated protein kinase (AMPK) results in vasodilatation and is therefore a potential therapeutic strategy for restoring uteroplacental perfusion in pregnancy disorders. In this study, C57Bl/6 mice were treated with subcutaneous pellets containing vehicle, the AMPK activator AICAR (200 mg kg-1 day-1 ), or the AMPK inhibitor Compound C (20 mg kg-1 day-1 ) beginning on gestational day 13.5, and were exposed to hypoxia starting on gestational day 14.5 that induced intrauterine growth restriction. Pharmacological AMPK activation by AICAR partially prevented hypoxia-induced fetal growth restriction (P < 0.01), due in part to increased uterine artery blood flow (P < 0.0001). The proportion of total cardiac output flowing through the uterine artery was increased with AICAR in hypoxic mice (P < 0.001), suggesting that the vasodilator effect of AICAR was selective for the uterine circulation. Further, pharmacological inhibition of AMPK with Compound C reduced uterine artery diameter and increased uterine artery contractility in normoxic mice, providing evidence that physiological levels of AMPK activation are necessary for vasodilatation in healthy pregnancy. Two-way ANOVA analyses indicated that hypoxia reduced AMPK activation in the uterine artery and placenta, and AICAR increased AMPK activation in these tissues compared to vehicle. These findings provide support for further investigation into the utility of pharmacological AMPK activation for treatment of fetal growth restriction.
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Affiliation(s)
- Sydney L Lane
- Integrated Physiology PhD Program, University of Colorado Graduate School, Aurora, CO, USA.,Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado School of Medicine, Aurora, CO, USA
| | - Julie A Houck
- Division of Bioinformatics and Personalized Medicine, Department of Medicine, University of Colorado School of Medicine, Aurora, CO, USA
| | - Alexandrea S Doyle
- Division of Bioinformatics and Personalized Medicine, Department of Medicine, University of Colorado School of Medicine, Aurora, CO, USA
| | - Elise S Bales
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado School of Medicine, Aurora, CO, USA
| | - Ramón A Lorca
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado School of Medicine, Aurora, CO, USA
| | - Colleen G Julian
- Division of Bioinformatics and Personalized Medicine, Department of Medicine, University of Colorado School of Medicine, Aurora, CO, USA
| | - Lorna G Moore
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado School of Medicine, Aurora, CO, USA
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Sherk VD, Jackman MR, Higgins JA, Giles ED, Foright RM, Presby DM, Carpenter RD, Johnson GC, Oljira R, Houck JA, Maclean PS. Impact of Exercise and Activity on Weight Regain and Musculoskeletal Health Post-Ovariectomy. Med Sci Sports Exerc 2020; 51:2465-2473. [PMID: 31274683 DOI: 10.1249/mss.0000000000002082] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The purpose of this study was to determine whether obesity and/or exercise training alters weight regain and musculoskeletal health after ovariectomy (OVX). Female rats were fed high-fat diet (HFD) to reveal obesity-prone (OP) and obesity-resistant (OR) phenotypes. The OP and OR exercising (EX) and sedentary (SED) rats were calorically restricted to lose 15% of body weight using medium-fat diet. Rats were then maintained in energy balance for 8 wk before OVX. After OVX and a brief calorically limited phase, rats were allowed to eat ad libitum until body weight plateaued. Starting at weight loss, EX ran 1 h·d, 6 d·wk, 15 m·min. Energy intake, spontaneous physical activity (SPA), and total energy expenditure were evaluated at the end of weight maintenance pre-OVX, and at three time points post-OVX: before weight regain, during early regain, and after regain. Data are presented as mean ± SE. Exercise attenuated weight regain after OVX in OP only (OP-EX, 123 ± 10 g; OP-SED, 165 ± 12 g; OR-EX, 121 ± 6 g; OR-SED, 116 ± 6 g), which was primarily an attenuation of fat gain. The early post-OVX increase in energy intake explained much of the weight regain, and was similar across groups. Exercising improved bone strength, as did maintaining SPA. Group differences in muscle mitochondrial respiration were not significant. The large decrease in SPA due to OVX was persistent, but early weight regain was dependent on decreased SPA. In conclusion, leanness and exercise do not necessarily protect from OVX-induced weight gain. Exercise prevented weight gain in obese rats, but loss of SPA was the greatest contributor to post-OVX weight gain. Thus, understanding the mechanisms resulting in reduction in SPA after ovarian hormone loss is critical in the prevention of menopause-associated metabolic dysfunction.
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Affiliation(s)
- Vanessa D Sherk
- Division of Endocrinology, Metabolism and Diabetes, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO
| | - Matthew R Jackman
- Division of Endocrinology, Metabolism and Diabetes, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO
| | - Janine A Higgins
- Section of Endocrinology, Department of Pediatrics, University of Colorado Anschutz Medical Campus, Aurora, CO
| | - Erin D Giles
- Division of Endocrinology, Metabolism and Diabetes, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO.,Department of Nutrition and Food Science, Texas A&M University, College Station, TX
| | - Rebecca M Foright
- Division of Endocrinology, Metabolism and Diabetes, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO
| | - David M Presby
- Division of Endocrinology, Metabolism and Diabetes, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO
| | - R Dana Carpenter
- Department of Mechanical Engineering, University of Colorado Anschutz Medical Campus, Aurora, CO
| | - Ginger C Johnson
- Division of Endocrinology, Metabolism and Diabetes, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO
| | - Robera Oljira
- Division of Endocrinology, Metabolism and Diabetes, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO
| | - Julie A Houck
- Division of Endocrinology, Metabolism and Diabetes, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO
| | - Paul S Maclean
- Division of Endocrinology, Metabolism and Diabetes, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO
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11
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Lorca RA, Matarazzo CJ, Bales ES, Houck JA, Orlicky DJ, Euser AG, Julian CG, Moore LG. AMPK activation in pregnant human myometrial arteries from high-altitude and intrauterine growth-restricted pregnancies. Am J Physiol Heart Circ Physiol 2020; 319:H203-H212. [PMID: 32502374 DOI: 10.1152/ajpheart.00644.2019] [Citation(s) in RCA: 11] [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] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
High-altitude (>2,500 m) residence increases the incidence of intrauterine growth restriction (IUGR) due, in part, to reduced uterine artery blood flow and impaired myometrial artery (MA) vasodilator response. A role for the AMP-activated protein kinase (AMPK) pathway in protecting against hypoxia-associated IUGR is suggested by genomic and transcriptomic studies in humans and functional studies in mice. AMPK is a hypoxia-sensitive metabolic sensor with vasodilatory properties. Here we hypothesized that AMPK-dependent vasodilation was increased in MAs from high versus low-altitude (<1,700 m) Colorado women with appropriate for gestational age (AGA) pregnancies and reduced in IUGR pregnancies regardless of altitude. Vasoreactivity studies showed that, in AGA pregnancies, MAs from high-altitude women were more sensitive to vasodilation by activation of AMPK with A769662 due chiefly to increased endothelial nitric oxide production, whereas MA responses to AMPK activation in the low-altitude women were endothelium independent. MAs from IUGR compared with AGA pregnancies had blunted vasodilator responses to acetylcholine at high altitude. We concluded that 1) blunted vasodilator responses in IUGR pregnancies confirm the importance of MA vasodilation for normal fetal growth and 2) the increased sensitivity to AMPK activation in AGA pregnancies at high altitude suggests that AMPK activation helped maintain MA vasodilation and fetal growth. These results highlight a novel mechanism for vasodilation of MAs under conditions of chronic hypoxia and suggest that AMPK activation could provide a therapy for increasing uteroplacental blood flow and improving fetal growth in IUGR pregnancies.NEW & NOTEWORTHY Intrauterine growth restriction (IUGR) impairs infant well- being and increases susceptibility to later-in-life diseases for mother and child. Our study reveals a novel role for AMPK in vasodilating the myometrial artery (MA) from women residing at high altitude (>2,500 m) with appropriate for gestational age pregnancies but not in IUGR pregnancies at any altitude.
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Affiliation(s)
- Ramón A Lorca
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Denver-Anschutz Medical Campus, Aurora, Colorado
| | - Christopher J Matarazzo
- Division of Biomedical Informatics and Personalized Medicine, Department of Medicine, University of Colorado Denver-Anschutz Medical Campus, Aurora, Colorado
| | - Elise S Bales
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Denver-Anschutz Medical Campus, Aurora, Colorado
| | - Julie A Houck
- Division of Biomedical Informatics and Personalized Medicine, Department of Medicine, University of Colorado Denver-Anschutz Medical Campus, Aurora, Colorado
| | - David J Orlicky
- Department of Pathology, University of Colorado Denver-Anschutz Medical Campus, Aurora, Colorado
| | - Anna G Euser
- Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, University of Colorado Denver-Anschutz Medical Campus, Aurora, Colorado
| | - Colleen G Julian
- Division of Biomedical Informatics and Personalized Medicine, Department of Medicine, University of Colorado Denver-Anschutz Medical Campus, Aurora, Colorado
| | - Lorna G Moore
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Denver-Anschutz Medical Campus, Aurora, Colorado
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12
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Nahomi RB, Nam MH, Rankenberg J, Rakete S, Houck JA, Johnson GC, Stankowska DL, Pantcheva MB, MacLean PS, Nagaraj RH. Kynurenic Acid Protects Against Ischemia/Reperfusion-Induced Retinal Ganglion Cell Death in Mice. Int J Mol Sci 2020; 21:ijms21051795. [PMID: 32151061 PMCID: PMC7084183 DOI: 10.3390/ijms21051795] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [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: 02/01/2020] [Revised: 02/21/2020] [Accepted: 03/02/2020] [Indexed: 12/17/2022] Open
Abstract
Background: Glaucoma is an optic neuropathy and involves the progressive degeneration of retinal ganglion cells (RGCs), which leads to blindness in patients. We investigated the role of the neuroprotective kynurenic acid (KYNA) in RGC death against retinal ischemia/reperfusion (I/R) injury. Methods: We injected KYNA intravenously or intravitreally to mice. We generated a knockout mouse strain of kynurenine 3-monooxygenase (KMO), an enzyme in the kynurenine pathway that produces neurotoxic 3-hydroxykynurenine. To test the effect of mild hyperglycemia on RGC protection, we used streptozotocin (STZ) induced diabetic mice. Retinal I/R injury was induced by increasing intraocular pressure for 60 min followed by reperfusion and RGC numbers were counted in the retinal flat mounts. Results: Intravenous or intravitreal administration of KYNA protected RGCs against I/R injury. The I/R injury caused a greater loss of RGCs in wild type than in KMO knockout mice. KMO knockout mice had mildly higher levels of fasting blood glucose than wild type mice. Diabetic mice showed significantly lower loss of RGCs when compared with non-diabetic mice subjected to I/R injury. Conclusion: Together, our study suggests that the absence of KMO protects RGCs against I/R injury, through mechanisms that likely involve higher levels of KYNA and glucose.
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Affiliation(s)
- Rooban B. Nahomi
- Sue Anschutz-Rodgers Eye Center and Department of Ophthalmology, University of Colorado, Aurora, CO 80045, USA; (M.-H.N.); (J.R.); (S.R.); (M.B.P.)
- Correspondence: (R.B.N.); (R.H.N.); Tel.: +1-303-724-8824 (R.H.N.)
| | - Mi-Hyun Nam
- Sue Anschutz-Rodgers Eye Center and Department of Ophthalmology, University of Colorado, Aurora, CO 80045, USA; (M.-H.N.); (J.R.); (S.R.); (M.B.P.)
| | - Johanna Rankenberg
- Sue Anschutz-Rodgers Eye Center and Department of Ophthalmology, University of Colorado, Aurora, CO 80045, USA; (M.-H.N.); (J.R.); (S.R.); (M.B.P.)
| | - Stefan Rakete
- Sue Anschutz-Rodgers Eye Center and Department of Ophthalmology, University of Colorado, Aurora, CO 80045, USA; (M.-H.N.); (J.R.); (S.R.); (M.B.P.)
| | - Julie A. Houck
- Division of Endocrinology, Metabolism and Diabetes, School of Medicine, University of Colorado, Aurora, CO 80045, USA; (J.A.H.); (G.C.J.); (P.S.M.)
| | - Ginger C. Johnson
- Division of Endocrinology, Metabolism and Diabetes, School of Medicine, University of Colorado, Aurora, CO 80045, USA; (J.A.H.); (G.C.J.); (P.S.M.)
| | - Dorota L. Stankowska
- Department of Pharmacology and Neuroscience, North Texas Eye Research Institute, University of North Texas Health Science Center, Fort Worth, TX 76107, USA;
| | - Mina B. Pantcheva
- Sue Anschutz-Rodgers Eye Center and Department of Ophthalmology, University of Colorado, Aurora, CO 80045, USA; (M.-H.N.); (J.R.); (S.R.); (M.B.P.)
| | - Paul S. MacLean
- Division of Endocrinology, Metabolism and Diabetes, School of Medicine, University of Colorado, Aurora, CO 80045, USA; (J.A.H.); (G.C.J.); (P.S.M.)
| | - Ram H. Nagaraj
- Sue Anschutz-Rodgers Eye Center and Department of Ophthalmology, University of Colorado, Aurora, CO 80045, USA; (M.-H.N.); (J.R.); (S.R.); (M.B.P.)
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado, Aurora, CO 80045, USA
- Correspondence: (R.B.N.); (R.H.N.); Tel.: +1-303-724-8824 (R.H.N.)
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Lane SL, Doyle AS, Bales ES, Houck JA, Lorca RA, Moore LG, Julian CG. Peroxisome proliferator-activated receptor gamma blunts endothelin-1-mediated contraction of the uterine artery in a murine model of high-altitude pregnancy. FASEB J 2020; 34:4283-4292. [PMID: 31970838 DOI: 10.1096/fj.201902264rr] [Citation(s) in RCA: 2] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2019] [Revised: 01/02/2020] [Accepted: 01/08/2020] [Indexed: 01/12/2023]
Abstract
The environmental hypoxia of high altitude (HA) increases the incidence of intrauterine growth restriction (IUGR) approximately threefold. The peroxisome proliferator-activated receptor γ (PPAR-γ), a ligand-activated nuclear receptor that promotes vasorelaxation by increasing nitric oxide and downregulating endothelin-1 (ET-1) production, has been implicated in IUGR. Based on our prior work indicating that pharmacologic activation of the PPARγ pathway protects against hypoxia-associated IUGR, we used an experimental murine model to determine whether such effects may be attributed to vasodilatory effects in the uteroplacental circulation. Using wire myography, ex vivo vasoreactivity studies were conducted in uterine arteries (UtA) isolated from pregnant mice exposed to hypoxia or normoxia from gestational day 14.5 to 18.5. Exposure to troglitazone, a high-affinity PPARγ agonist-induced vasorelaxation in UtA preconstricted with phenylephrine, with HA-UtA showing increased sensitivity. Troglitazone blunted ET-1-induced contraction of UtA in hypoxic and normoxic dams equivalently. Immunohistological analysis revealed enhanced staining for ET-1 receptors in the placental labyrinthine zone in hypoxic compared to normoxic dams. Our results suggest that pharmacologic PPAR-γ activation, via its vasoactive properties, may protect the fetal growth under hypoxic conditions by improving uteroplacental perfusion and thereby justify further investigation into PPARγ as a therapeutic target for IUGR in pregnancies complicated by hypoxia.
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Affiliation(s)
- Sydney L Lane
- Integrated Physiology Program, University of Colorado Graduate School, Aurora, CO, USA.,Department of Obstetrics and Gynecology, University of Colorado School of Medicine, Aurora, CO, USA
| | - Alexandrea S Doyle
- Department of Biochemistry, Colorado Mesa University, Grand Junction, CO, USA
| | - Elise S Bales
- Department of Obstetrics and Gynecology, University of Colorado School of Medicine, Aurora, CO, USA
| | - Julie A Houck
- Department of Biochemistry, Colorado Mesa University, Grand Junction, CO, USA
| | - Ramón A Lorca
- Department of Obstetrics and Gynecology, University of Colorado School of Medicine, Aurora, CO, USA
| | - Lorna G Moore
- Department of Obstetrics and Gynecology, University of Colorado School of Medicine, Aurora, CO, USA
| | - Colleen G Julian
- Department of Medicine, University of Colorado School of Medicine, Aurora, CO, USA
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Presby DM, Checkley LA, Jackman MR, Higgins JA, Jones KL, Giles ED, Houck JA, Webb PG, Steig AJ, Johnson GC, Rudolph MC, MacLean PS. Regular exercise potentiates energetically expensive hepatic de novo lipogenesis during early weight regain. Am J Physiol Regul Integr Comp Physiol 2019; 317:R684-R695. [PMID: 31553623 DOI: 10.1152/ajpregu.00074.2019] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [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: 12/11/2022]
Abstract
Exercise is a potent facilitator of long-term weight loss maintenance (WLM), whereby it decreases appetite and increases energy expenditure beyond the cost of the exercise bout. We have previously shown that exercise may amplify energy expenditure through energetically expensive nutrient deposition. Therefore, we investigated the effect of exercise on hepatic de novo lipogenesis (DNL) during WLM and relapse to obesity. Obese rats were calorically restricted with (EX) or without (SED) treadmill exercise (1 h/day, 6 days/wk, 15 m/min) to induce and maintain weight loss. After 6 wk of WLM, subsets of WLM-SED and WLM-EX rats were allowed ad libitum access to food for 1 day to promote relapse (REL). An energy gap-matched group of sedentary, relapsing rats (REL-GM) were provided a diet matched to the positive energy imbalance of the REL-EX rats. During relapse, exercise increased enrichment of hepatic DN-derived lipids and induced hepatic molecular adaptations favoring DNL compared with the gap-matched controls. In the liver, compared with both REL-SED and REL-GM rats, REL-EX rats had lower hepatic expression of genes required for cholesterol biosynthesis; greater hepatic expression of genes that mediate very low-density lipoprotein synthesis and secretion; and greater mRNA expression of Cyp27a1, which encodes an enzyme involved in the biosynthesis of bile acids. Altogether, these data provide compelling evidence that the liver has an active role in exercise-mediated potentiation of energy expenditure during early relapse.
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Affiliation(s)
- David M Presby
- Division of Endocrinology, Metabolism and Diabetes, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado
| | - L Allyson Checkley
- Division of Endocrinology, Metabolism and Diabetes, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado
| | - Matthew R Jackman
- Division of Endocrinology, Metabolism and Diabetes, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado
| | - Janine A Higgins
- Department of Pediatrics, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado
| | - Kenneth L Jones
- Department of Pediatrics, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado
| | - Erin D Giles
- Department of Nutrition and Food Science at Texas A&M University, College Station, Texas
| | - Julie A Houck
- Division of Endocrinology, Metabolism and Diabetes, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado
| | - Patricia G Webb
- Division of Endocrinology, Metabolism and Diabetes, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado
| | - Amy J Steig
- Center for Human Nutrition at the University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado
| | - Ginger C Johnson
- Division of Endocrinology, Metabolism and Diabetes, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado
| | - Michael C Rudolph
- Division of Endocrinology, Metabolism and Diabetes, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado
| | - Paul S MacLean
- Division of Endocrinology, Metabolism and Diabetes, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado.,Department of Pathology, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado.,Center for Human Nutrition at the University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado
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Presby DM, Jackman MR, Rudolph MC, Sherk VD, Foright RM, Houck JA, Johnson GC, Orlicky DJ, Melanson EL, Higgins JA, MacLean PS. Compensation for cold-induced thermogenesis during weight loss maintenance and regain. Am J Physiol Endocrinol Metab 2019; 316:E977-E986. [PMID: 30912962 PMCID: PMC6580173 DOI: 10.1152/ajpendo.00543.2018] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [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: 12/13/2018] [Revised: 03/19/2019] [Accepted: 03/19/2019] [Indexed: 11/22/2022]
Abstract
Prevalence of obesity is exacerbated by low rates of successful long-term weight loss maintenance (WLM). In part, relapse from WLM to obesity is due to a reduction in energy expenditure (EE) that persists throughout WLM and relapse. Thus, interventions that increase EE might facilitate WLM. In obese mice that were calorically restricted to reduce body weight by ~20%, we manipulated EE throughout WLM and early relapse using intermittent cold exposure (ICE; 4°C, 90 min/day, 5 days/wk, within the last 3 h of the light cycle). EE, energy intake, and spontaneous physical activity were measured during the obese, WLM, and relapse phases. During WLM and relapse, the ICE group expended more energy during the light cycle because of cold exposure but expended less energy in the dark cycle, which led to no overall difference in total daily EE. The compensation in EE appeared to be mediated by activity, whereby the ICE group was more active during the light cycle because of cold exposure but less active during the dark cycle, which led to no overall effect on total daily activity during WLM and relapse. In brown adipose tissue of relapsing mice, the ICE group had greater mRNA expression of Dio2 and protein expression of UCP1 but lower mRNA expression of Prdm16. In summary, these findings indicate that despite robust increases in EE during cold exposures, ICE is unable to alter total daily EE during WLM or early relapse, likely due to compensatory behaviors in activity.
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Affiliation(s)
- David M Presby
- Department of Medicine, Division of Endocrinology, Metabolism and Diabetes, University of Colorado Anschutz Medical Campus , Aurora, Colorado
| | - Matthew R Jackman
- Department of Medicine, Division of Endocrinology, Metabolism and Diabetes, University of Colorado Anschutz Medical Campus , Aurora, Colorado
| | - Michael C Rudolph
- Department of Medicine, Division of Endocrinology, Metabolism and Diabetes, University of Colorado Anschutz Medical Campus , Aurora, Colorado
| | - Vanessa D Sherk
- Department of Medicine, Division of Endocrinology, Metabolism and Diabetes, University of Colorado Anschutz Medical Campus , Aurora, Colorado
| | - Rebecca M Foright
- Department of Medicine, Division of Endocrinology, Metabolism and Diabetes, University of Colorado Anschutz Medical Campus , Aurora, Colorado
| | - Julie A Houck
- Department of Medicine, Division of Endocrinology, Metabolism and Diabetes, University of Colorado Anschutz Medical Campus , Aurora, Colorado
| | - Ginger C Johnson
- Department of Medicine, Division of Endocrinology, Metabolism and Diabetes, University of Colorado Anschutz Medical Campus , Aurora, Colorado
| | - David J Orlicky
- Department of Pathology, University of Colorado Anschutz Medical Campus , Aurora, Colorado
| | - Edward L Melanson
- Department of Medicine, Division of Endocrinology, Metabolism and Diabetes, University of Colorado Anschutz Medical Campus , Aurora, Colorado
- Division of Geriatric Medicine, University of Colorado Anschutz Medical Campus , Aurora, Colorado
| | - Janine A Higgins
- Department of Pediatrics, Section of Endocrinology, University of Colorado Anschutz Medical Campus , Aurora, Colorado
| | - Paul S MacLean
- Department of Medicine, Division of Endocrinology, Metabolism and Diabetes, University of Colorado Anschutz Medical Campus , Aurora, Colorado
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Rudolph MC, Jackman MR, Presby DM, Houck JA, Webb PG, Johnson GC, Soderborg TK, de la Houssaye BA, Yang IV, Friedman JE, MacLean PS. Low Neonatal Plasma n-6/n-3 PUFA Ratios Regulate Offspring Adipogenic Potential and Condition Adult Obesity Resistance. Diabetes 2018; 67:651-661. [PMID: 29138256 PMCID: PMC5860857 DOI: 10.2337/db17-0890] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [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: 07/31/2017] [Accepted: 11/06/2017] [Indexed: 01/08/2023]
Abstract
Adipose tissue expansion progresses rapidly during postnatal life, influenced by both prenatal maternal factors and postnatal developmental cues. The ratio of omega-6 (n-6) relative to n-3 polyunsaturated fatty acids (PUFAs) is believed to regulate perinatal adipogenesis, but the cellular mechanisms and long-term effects are not well understood. We lowered the fetal and postnatal n-6/n-3 PUFA ratio exposure in wild-type offspring under standard maternal dietary fat amounts to test the effects of low n-6/n-3 ratios on offspring adipogenesis and adipogenic potential. Relative to wild-type pups receiving high perinatal n-6/n-3 ratios, subcutaneous adipose tissue in 14-day-old wild-type pups receiving low n-6/n-3 ratios had more adipocytes that were smaller in size; decreased Pparγ2, Fabp4, and Plin1; several lipid metabolism mRNAs; coincident hypermethylation of the PPARγ2 proximal promoter; and elevated circulating adiponectin. As adults, offspring that received low perinatal n-6/n-3 ratios were diet-induced obesity (DIO) resistant and had a lower positive energy balance and energy intake, greater lipid fuel preference and non-resting energy expenditure, one-half the body fat, and better glucose clearance. Together, the findings support a model in which low early-life n-6/n-3 ratios remodel adipose morphology to increase circulating adiponectin, resulting in a persistent adult phenotype with improved metabolic flexibility that prevents DIO.
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Affiliation(s)
- Michael C Rudolph
- Division of Endocrinology, Metabolism and Diabetes, University of Colorado School of Medicine, Aurora, CO
| | - Matthew R Jackman
- Division of Endocrinology, Metabolism and Diabetes, University of Colorado School of Medicine, Aurora, CO
| | - David M Presby
- Division of Endocrinology, Metabolism and Diabetes, University of Colorado School of Medicine, Aurora, CO
| | - Julie A Houck
- Division of Endocrinology, Metabolism and Diabetes, University of Colorado School of Medicine, Aurora, CO
| | - Patricia G Webb
- Division of Endocrinology, Metabolism and Diabetes, University of Colorado School of Medicine, Aurora, CO
| | - Ginger C Johnson
- Division of Endocrinology, Metabolism and Diabetes, University of Colorado School of Medicine, Aurora, CO
| | - Taylor K Soderborg
- Department of Pediatrics, Section of Neonatology, University of Colorado School of Medicine, Aurora, CO
| | - Becky A de la Houssaye
- Department of Pediatrics, Section of Neonatology, University of Colorado School of Medicine, Aurora, CO
| | - Ivana V Yang
- Division of Biomedical Informatics and Personalized Medicine, University of Colorado School of Medicine, Aurora, CO
| | - Jacob E Friedman
- Division of Endocrinology, Metabolism and Diabetes, University of Colorado School of Medicine, Aurora, CO
- Department of Pediatrics, Section of Neonatology, University of Colorado School of Medicine, Aurora, CO
| | - Paul S MacLean
- Division of Endocrinology, Metabolism and Diabetes, University of Colorado School of Medicine, Aurora, CO
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Sherk VD, Jackman MR, Giles ED, Higgins JA, Foright RM, Presby DM, Johnson GC, Houck JA, Houser JL, Oljira R, MacLean PS. Prior weight loss exacerbates the biological drive to gain weight after the loss of ovarian function. Physiol Rep 2018; 5:e13272. [PMID: 28533263 PMCID: PMC5449558 DOI: 10.14814/phy2.13272] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2017] [Accepted: 04/04/2017] [Indexed: 02/01/2023] Open
Abstract
Both the history of obesity and weight loss may change how menopause affects metabolic health. The purpose was to determine whether obesity and/or weight loss status alters energy balance (EB) and subsequent weight gain after the loss of ovarian function. Female lean and obese Wistar rats were randomized to 15% weight loss (WL) or ad libitum fed controls (CON). After the weight loss period, WL rats were kept in EB at the reduced weight for 8 weeks prior to ovariectomy (OVX). After OVX, all rats were allowed to eat ad libitum until weight plateaued. Energy intake (EI), spontaneous physical activity, and total energy expenditure (TEE) were measured with indirect calorimetry before OVX, immediately after OVX, and after weight plateau. Changes in energy intake (EI), TEE, and weight gain immediately after OVX were similar between lean and obese rats. However, obese rats gained more total weight and fat mass than lean rats over the full regain period. Post-OVX, EI increased more (P ≤ 0.03) in WL rats (58.9 ± 3.5 kcal/d) than CON rats (8.5 ± 5.2 kcal/d), and EI partially normalized (change from preOVX: 20.5 ± 4.2 vs. 1.5 ± 4.9 kcal/day) by the end of the study. As a result, WL rats gained weight (week 1:44 ± 20 vs. 7 ± 25 g) more rapidly (mean = 44 ± 20 vs. 7 ± 25 g/week; P < 0.001) than CON Prior obesity did not affect changes in EB or weight regain following OVX, whereas a history of weight loss prior to OVX augmented disruptions in EB after OVX, resulting in more rapid weight regain.
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Affiliation(s)
- Vanessa D Sherk
- Division of Endocrinology, Metabolism, and Diabetes, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado
| | - Matthew R Jackman
- Division of Endocrinology, Metabolism, and Diabetes, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado
| | - Erin D Giles
- Department of Nutrition & Food Science, Texas A&M University, College Station, Texas
| | - Janine A Higgins
- Section of Endocrinology, Department of Pediatrics, University of Colorado Anschutz Medical Campus, Aurora, Colorado
| | - Rebecca M Foright
- Division of Endocrinology, Metabolism, and Diabetes, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado
| | - David M Presby
- Division of Endocrinology, Metabolism, and Diabetes, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado
| | - Ginger C Johnson
- Division of Endocrinology, Metabolism, and Diabetes, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado
| | - Julie A Houck
- Division of Endocrinology, Metabolism, and Diabetes, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado
| | - Jordan L Houser
- Division of Endocrinology, Metabolism, and Diabetes, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado
| | - Robera Oljira
- Division of Endocrinology, Metabolism, and Diabetes, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado
| | - Paul S MacLean
- Division of Endocrinology, Metabolism, and Diabetes, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado
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Checkley LA, Rudolph MC, Wellberg EA, Giles ED, Wahdan-Alaswad RS, Houck JA, Edgerton SM, Thor AD, Schedin P, Anderson SM, MacLean PS. Metformin Accumulation Correlates with Organic Cation Transporter 2 Protein Expression and Predicts Mammary Tumor Regression In Vivo. Cancer Prev Res (Phila) 2017; 10:198-207. [PMID: 28154203 DOI: 10.1158/1940-6207.capr-16-0211-t] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2016] [Revised: 01/19/2017] [Accepted: 01/20/2017] [Indexed: 02/07/2023]
Abstract
Several epidemiologic studies have associated metformin treatment with a reduction in breast cancer incidence in prediabetic and type II diabetic populations. Uncertainty exists regarding which patient populations and/or tumor subtypes will benefit from metformin treatment, and most preclinical in vivo studies have given little attention to the cellular pharmacology of intratumoral metformin uptake. Epidemiologic reports consistently link western-style high fat diets (HFD), which drive overweight and obesity, with increased risk of breast cancer. We used a rat model of HFD-induced overweight and mammary carcinogenesis to define intratumoral factors that confer metformin sensitivity. Mammary tumors were initiated with 1-methyl-1-nitrosourea, and rats were randomized into metformin-treated (2 mg/mL drinking water) or control groups (water only) for 8 weeks. Two-thirds of existing mammary tumors responded to metformin treatment with decreased tumor volumes (P < 0.05), reduced proliferative index (P < 0.01), and activated AMPK (P < 0.05). Highly responsive tumors accumulated 3-fold greater metformin amounts (P < 0.05) that were positively correlated with organic cation transporter-2 (OCT2) protein expression (r = 0.57; P = 0.038). Importantly, intratumoral metformin concentration negatively associated with tumor volume (P = 0.03), and each 10 pmol increase in intratumoral metformin predicted >0.11 cm3 reduction in tumor volume. Metformin treatment also decreased proinflammatory arachidonic acid >1.5-fold in responsive tumors (P = 0.023). Collectively, these preclinical data provide evidence for a direct effect of metformin in vivo and suggest that OCT2 expression may predict metformin uptake and tumor response. Cancer Prev Res; 10(3); 198-207. ©2017 AACR.
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Affiliation(s)
- L Allyson Checkley
- Division of Endocrinology, Metabolism and Diabetes, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado
| | - Michael C Rudolph
- Division of Endocrinology, Metabolism and Diabetes, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado
| | - Elizabeth A Wellberg
- Department of Pathology, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado
| | - Erin D Giles
- Department of Nutrition and Food Science, Texas A&M University, College Station, Texas
| | - Reema S Wahdan-Alaswad
- Department of Pathology, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado
| | - Julie A Houck
- Division of Endocrinology, Metabolism and Diabetes, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado
| | - Susan M Edgerton
- Department of Pathology, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado
| | - Ann D Thor
- Department of Pathology, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado
| | - Pepper Schedin
- Department of Cell, Developmental and Cancer Biology, Oregon Health & Science University, Portland, Oregon.,Knight Cancer Institute, Oregon Health & Science University, Portland, Oregon
| | - Steven M Anderson
- Department of Pathology, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado
| | - Paul S MacLean
- Division of Endocrinology, Metabolism and Diabetes, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado. .,Department of Pathology, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado.,Center for Human Nutrition, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado
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19
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Sherk VD, Foright R, Giles ED, Johnson GC, Lopez JL, Houck JA, Higgins JA, Jackman MR, MacLean PS. Initial Disruptions In Energy Balance After The Loss Of Ovarian Function Do Not Depend On Exercise Training Or Obesity Status In Rats. Med Sci Sports Exerc 2015. [DOI: 10.1249/01.mss.0000479060.97042.52] [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: 11/21/2022]
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20
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McCurdy CE, Schenk S, Holliday MJ, Philp A, Houck JA, Patsouris D, MacLean PS, Majka SM, Klemm DJ, Friedman JE. Attenuated Pik3r1 expression prevents insulin resistance and adipose tissue macrophage accumulation in diet-induced obese mice. Diabetes 2012; 61:2495-505. [PMID: 22698915 PMCID: PMC3447911 DOI: 10.2337/db11-1433] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Obese white adipose tissue (AT) is characterized by large-scale infiltration of proinflammatory macrophages, in parallel with systemic insulin resistance; however, the cellular stimulus that initiates this signaling cascade and chemokine release is still unknown. The objective of this study was to determine the role of the phosphoinositide 3-kinase (PI3K) regulatory subunits on AT macrophage (ATM) infiltration in obesity. Here, we find that the Pik3r1 regulatory subunits (i.e., p85α/p55α/p50α) are highly induced in AT from high-fat diet-fed obese mice, concurrent with insulin resistance. Global heterozygous deletion of the Pik3r1 regulatory subunits (αHZ), but not knockout of Pik3r2 (p85β), preserves whole-body, AT, and skeletal muscle insulin sensitivity, despite severe obesity. Moreover, ATM accumulation, proinflammatory gene expression, and ex vivo chemokine secretion in obese αHZ mice are markedly reduced despite endoplasmic reticulum (ER) stress, hypoxia, adipocyte hypertrophy, and Jun NH(2)-terminal kinase activation. Furthermore, bone marrow transplant studies reveal that these improvements in obese αHZ mice are independent of reduced Pik3r1 expression in the hematopoietic compartment. Taken together, these studies demonstrate that Pik3r1 expression plays a critical role in mediating AT insulin sensitivity and, more so, suggest that reduced PI3K activity is a key step in the initiation and propagation of the inflammatory response in obese AT.
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Affiliation(s)
- Carrie E McCurdy
- Department of Pediatrics, University of Colorado School of Medicine, Aurora, Colorado, USA.
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21
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Heil GL, McCarthy T, Yoon KJ, Liu S, Saad MD, Smith CB, Houck JA, Dawson ED, Rowlen KL, Gray GC. MChip, a low density microarray, differentiates among seasonal human H1N1, North American swine H1N1, and the 2009 pandemic H1N1. Influenza Other Respir Viruses 2011; 4:411-6. [PMID: 20958936 PMCID: PMC3825186 DOI: 10.1111/j.1750-2659.2010.00185.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [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] [Indexed: 11/28/2022] Open
Abstract
BACKGROUND The MChip uses data from the hybridization of amplified viral RNA to 15 distinct oligonucleotides that target the influenza A matrix (M) gene segment. An artificial neural network (ANN) automates the interpretation of subtle differences in fluorescence intensity patterns from the microarray. The complete process from clinical specimen to identification including amplification of viral RNA can be completed in <8 hours for under US$10. OBJECTIVES The work presented here represents an effort to expand and test the capabilities of the MChip to differentiate influenza A/H1N1 of various species origin. METHODS The MChip ANN was trained to recognize fluorescence image patterns of a variety of known influenza A viruses, including examples of human H1N1, human H3N2, swine H1N1, 2009 pandemic influenza A H1N1, and a wide variety of avian, equine, canine, and swine influenza viruses. Robustness of the MChip ANN was evaluated using 296 blinded isolates. RESULTS Training of the ANN was expanded by the addition of 71 well-characterized influenza A isolates and yielded relatively high accuracy (little misclassification) in distinguishing unique H1N1 strains: nine human A/H1N1 (88·9% correct), 35 human A/H3N2 (97·1% correct), 31 North American swine A/H1N1 (80·6% correct), 14 2009 pandemic A/H1N1 (87·7% correct), and 23 negative samples (91·3% correct). Genetic diversity among the swine H1N1 isolates may have contributed to the lower success rate for these viruses. CONCLUSIONS The current study demonstrates the MChip has the capability to differentiate the genetic variations among influenza viruses with appropriate ANN training. Further selective enrichment of the ANN will improve its ability to rapidly and reliably characterize influenza viruses of unknown origin.
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Affiliation(s)
- Gary L Heil
- Emerging Pathogens Institute and College of Public Health and Health Professions, The University of Florida, Gainesville, FL 32611, USA.
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22
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Houck JA, Hojgaard A, Piesman J, Kuchta RD. Low-density microarrays for the detection of Borrelia burgdorferi s.s. (the Lyme disease spirochete) in nymphal Ixodes scapularis. Ticks Tick Borne Dis 2010; 2:27-36. [PMID: 21771534 DOI: 10.1016/j.ttbdis.2010.10.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2010] [Revised: 10/05/2010] [Accepted: 10/15/2010] [Indexed: 11/29/2022]
Abstract
Lyme disease is the most common tick-borne disease in Europe and North America. In the hyperendemic Lyme disease regions of the eastern United States, nymphal Ixodes scapularis are the principal ticks transmitting the Lyme disease spirochete, Borrelia burgdorferi sensu stricto (s.s.). Approximately 25% of questing nymphs in endemic regions are infected with spirochetes. High throughput-sensitive and specific methods for testing nymphal I. scapularis for infection with B. burgdorferi are clearly needed. In the current study, we evaluated whether low-density microarrays could be adapted for the rapid and accurate detection and characterization of spirochetes in nymphal I. scapularis. Three different microarray platforms were developed and tested for the detection of spirochetes in ticks. They could both detect and differentiate different Borrelia genospecies, in one case detecting as few as a single copy of Borrelia DNA.
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Affiliation(s)
- Julie A Houck
- Department of Chemistry and Biochemistry, UCB 215, University of Colorado, Boulder, CO 80309, USA
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Abstract
The Recombigen-HIV-1 LA Test (Cambridge BioScience Corporation, Worcester, MA) uses recombinant peptides derived from the env gene product in a latex agglutination assay for the detection of antibodies to human immunodeficiency virus type 1 (HIV-1) and was recently approved by the Food and Drug Administration for marketing in the United States. It is intended for use as a screening test in physicians' offices, emergency rooms, and other settings where enzyme immunoassays are not practical or available. Concern has been raised over the sensitivity, specificity, and difficulty in interpretation of the agglutination pattern. The authors report on the sensitivity and interobserver variability of the assay as performed in a blinded fashion in a hospital laboratory by technologists experienced with other latex agglutination assays. In the first study, sera from 50 patients positive by enzyme immunoassay (EIA) (Abbott HIV EIA) and western blot (WB), performed with EPITOPE HIV western blot strips were assayed by one technologist using the latex agglutination technique. Forty-six samples were positive and four were negative, yielding a sensitivity of 92%. In the second study, 30 samples consisting of 10 negative by EIA and WB, 10 borderline by EIA and/or indeterminate by WB, and 10 positive by EIA and WB were evaluated by three technologists with the latex agglutination technique. There was agreement among all three technologists in 24 of 30 samples (80%). There was disagreement over one sample from the negative group (one technologist obtained a single false positive result), three from the borderline/indeterminate group, and two from the positive group (three technologists obtained false negative results on two samples). In summary, the authors report interobserver variation in interpreting 20% of tests, reflecting difficulty in assessing weak agglutination. Sensitivity of 92% is below that achievable with the EIA or WB techniques and limits the usefulness of the latex agglutination assay as a screening test.
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Affiliation(s)
- J A Houck
- Department of Pathology, Ohio State University, Columbus
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Houck JA, Lucas JG. Absence of Campylobacter-like organisms in Barrett's esophagus. Arch Pathol Lab Med 1989; 113:470-2. [PMID: 2712670] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Barrett's esophagus is a chronic condition in which the normal squamous mucosal lining is replaced by columnar mucosa. Campylobacter-like organism (CLOs) are implicated in the pathogenesis of gastritis and peptic ulcer disease and have been identified in Barrett's esophagus. The purpose of this study was to examine the incidence of CLOs in Barrett's esophagus and to consider their role, if any, in the pathogenesis of the disease. None of the bacteria were identified in 38 specimens obtained from 34 patients with Barrett's esophagus. It is concluded that the incidence of CLOs in Barrett's esophagus must be low and that CLOs do not contribute to the natural history of the disease.
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Affiliation(s)
- J A Houck
- Department of Pathology, Ohio State University Hospitals, Columbus 43210
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25
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Houck JA, Davis RE, Sharma HM. Thyroid-stimulating immunoglobulin as a cause of recurrent intrauterine fetal death. Obstet Gynecol 1988; 71:1018-9. [PMID: 2897651] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Hyperthyroidism is one of the numerous causes of infertility and recurrent abortion. Little mention has been made, however, of the specific role of thyroid-stimulating immunoglobulin (TSIg) as a potential etiology, especially in the clinically euthyroid mother. This report describes a case of intrauterine fetal death in a euthyroid woman with TSIg.
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Affiliation(s)
- J A Houck
- Department of Pathology, Ohio State University, Columbus
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