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Yu Y, Yin Y, Deng J, Yang X, Xiang Q, Yu R. Efficacy and optimal acupoints of auricular acupressure for treating prediabetes: a meta-analysis and data mining. Complement Ther Clin Pract 2025; 60:101998. [PMID: 40339435 DOI: 10.1016/j.ctcp.2025.101998] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2024] [Revised: 05/02/2025] [Accepted: 05/02/2025] [Indexed: 05/10/2025]
Abstract
BACKGROUND AND PURPOSE Auricular acupressure has potential in treating prediabetes; however, its effectiveness remains unclear. We aimed to evaluate the effect of auricular acupressure on blood glucose levels in patients with prediabetes and to identify optimal acupoints. METHODS We searched nine public databases for randomized controlled trials published before March 1, 2025, according to pre-established inclusion and exclusion criteria. The risk of bias was assessed using the Risk of Bias 2 tool. RevMan 5.3 was employed to conduct a meta-analysis on glycosylated hemoglobin A1c (HbA1c), fasting blood glucose (FBG), and 2-h postprandial blood glucose (2h-PBG) levels, and body mass index (BMI). We used a Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) approach to assess the certainty of evidence. Data mining was used to determine optimal acupoints. RESULTS This meta-analysis involved eight studies (694 participants). Compared with lifestyle intervention alone, auricular acupressure combined with lifestyle intervention significantly reduced HbA1c (mean difference [MD] -0.51, 95 % CI -0.84 to -0.18), FBG (MD -0.63, 95 % CI -0.94 to -0.31), and 2h-PBG (MD -0.78, 95 % CI -0.95 to -0.62) levels in patients with prediabetes but no significant effect was observed concerning BMI (MD -0.26, 95 % CI -1.15 to 0.63). The GRADE showed low to very low certainty levels of evidence. Data mining indicated that CO4, CO10, CO11, CO13, CO14, and CO17 were core acupoints for prediabetes. CONCLUSION Auricular acupressure demonstrates potential as a complementary approach for prediabetes, with CO4, CO10, CO11, CO13, CO14, and CO17 identified as optimal acupoints. However, due to methodological limitations, these findings require further validation through high-quality evidence.
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Affiliation(s)
- Yunfeng Yu
- School of Traditional Chinese Medicine, Hunan University of Chinese Medicine, Changsha, Hunan, China; The First Hospital of Hunan University of Chinese Medicine, Changsha, Hunan, China
| | - Yuman Yin
- School of Traditional Chinese Medicine, Hunan University of Chinese Medicine, Changsha, Hunan, China
| | - Juan Deng
- School of Traditional Chinese Medicine, Hunan University of Chinese Medicine, Changsha, Hunan, China
| | - Xinyu Yang
- School of Traditional Chinese Medicine, Hunan University of Chinese Medicine, Changsha, Hunan, China
| | - Qin Xiang
- School of Traditional Chinese Medicine, Hunan University of Chinese Medicine, Changsha, Hunan, China.
| | - Rong Yu
- School of Traditional Chinese Medicine, Hunan University of Chinese Medicine, Changsha, Hunan, China; The First Hospital of Hunan University of Chinese Medicine, Changsha, Hunan, China.
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2
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Takahashi T, Takase Y, Shiraishi A, Matsubara S, Watanabe T, Kirimoto S, Yamagaki T, Osawa M. Weight Gain With Advancing Age Is Controlled by the Muscarinic Acetylcholine Receptor M4 in Male Mice. Endocrinology 2025; 166:bqaf064. [PMID: 40179260 PMCID: PMC12012353 DOI: 10.1210/endocr/bqaf064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/15/2024] [Revised: 02/04/2025] [Accepted: 04/01/2025] [Indexed: 04/05/2025]
Abstract
Obesity is characterized by the excessive accumulation of adipose tissue, and it is a serious global health issue. Understanding the pathology of obesity is crucial for developing effective interventions. In this study, we investigated the role of muscarinic acetylcholine receptor M4 (mAChR-M4) in the regulation of obesity in Chrm4-knockout (M4-KO) mice. Male M4-KO mice showed higher weight gain and accumulation of white adipose tissue (WAT) with advancing age than the wild-type mice. The M4-KO mice also showed increased leptin expression at both the transcription and the translation levels. RNA sequencing and quantitative reverse transcription polymerase chain reaction analyses of subcutaneous adipose tissues revealed that the expression of WAT marker genes was significantly enhanced in the M4-KO mice. In contrast, the expression levels of brown adipose tissue/beige adipose tissue markers were strongly decreased in the M4-KO mice. To identify the Chrm4-expressing cell types, we generated Chrm4-mScarlet reporter mice and examined the localization of the mScarlet fluorescent signals in subcutaneous tissues. Fluorescent signals were prominently detected in WAT and mesenchymal stem cells. Additionally, we also found that choline acetyltransferase was expressed in macrophages, suggesting their involvement in acetylcholine (ACh) secretion. Corroborating this notion, we were able to quantitatively measure the ACh in subcutaneous tissues by liquid chromatography tandem mass spectrometry. Collectively, our findings suggest that endogenous ACh released from macrophages maintains the homeostasis of adipose cell growth and differentiation via mAChR-M4 in male mice. This study provides new insights into the molecular mechanisms underlying obesity and potential targets for therapeutic interventions.
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Affiliation(s)
- Toshio Takahashi
- Suntory Foundation for Life Sciences, Bioorganic Research Institute, Kyoto 619-0284, Japan
| | - Yuta Takase
- Suntory Foundation for Life Sciences, Bioorganic Research Institute, Kyoto 619-0284, Japan
| | - Akira Shiraishi
- Suntory Foundation for Life Sciences, Bioorganic Research Institute, Kyoto 619-0284, Japan
| | - Shin Matsubara
- Suntory Foundation for Life Sciences, Bioorganic Research Institute, Kyoto 619-0284, Japan
| | - Takehiro Watanabe
- Suntory Foundation for Life Sciences, Bioorganic Research Institute, Kyoto 619-0284, Japan
| | - Shinji Kirimoto
- Animal Science Business Unit, KAC Co., Ltd., Kyoto 604-8423, Japan
| | - Tohru Yamagaki
- Suntory Foundation for Life Sciences, Bioorganic Research Institute, Kyoto 619-0284, Japan
| | - Masatake Osawa
- Department of Regenerative Medicine and Applied Biomedical Sciences, Graduate School of Medicine, Gifu University, Gifu 501-1194, Japan
- Center for Highly Advanced Integration of Nano and Life Sciences, Gifu University, Gifu 501-1194, Japan
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3
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Korobkina ED, Calejman CM, Haley JA, Kelly ME, Li H, Gaughan M, Chen Q, Pepper HL, Ahmad H, Boucher A, Fluharty SM, Lin TY, Lotun A, Peura J, Trefely S, Green CR, Vo P, Semenkovich CF, Pitarresi JR, Spinelli JB, Aydemir O, Metallo CM, Lynes MD, Jang C, Snyder NW, Wellen KE, Guertin DA. Brown fat ATP-citrate lyase links carbohydrate availability to thermogenesis and guards against metabolic stress. Nat Metab 2024; 6:2187-2202. [PMID: 39402290 PMCID: PMC11841677 DOI: 10.1038/s42255-024-01143-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/23/2023] [Accepted: 09/16/2024] [Indexed: 11/28/2024]
Abstract
Brown adipose tissue (BAT) engages futile fatty acid synthesis-oxidation cycling, the purpose of which has remained elusive. Here, we show that ATP-citrate lyase (ACLY), which generates acetyl-CoA for fatty acid synthesis, promotes thermogenesis by mitigating metabolic stress. Without ACLY, BAT overloads the tricarboxylic acid cycle, activates the integrated stress response (ISR) and suppresses thermogenesis. ACLY's role in preventing BAT stress becomes critical when mice are weaned onto a carbohydrate-plentiful diet, while removing dietary carbohydrates prevents stress induction in ACLY-deficient BAT. ACLY loss also upregulates fatty acid synthase (Fasn); yet while ISR activation is not caused by impaired fatty acid synthesis per se, deleting Fasn and Acly unlocks an alternative metabolic programme that overcomes tricarboxylic acid cycle overload, prevents ISR activation and rescues thermogenesis. Overall, we uncover a previously unappreciated role for ACLY in mitigating mitochondrial stress that links dietary carbohydrates to uncoupling protein 1-dependent thermogenesis and provides fundamental insight into the fatty acid synthesis-oxidation paradox in BAT.
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Affiliation(s)
- Ekaterina D Korobkina
- Program in Molecular Medicine, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Camila Martinez Calejman
- Program in Molecular Medicine, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - John A Haley
- Program in Molecular Medicine, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Miranda E Kelly
- Department of Biological Chemistry, University of California Irvine, Irvine, CA, USA
| | - Huawei Li
- Program in Molecular Medicine, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Maria Gaughan
- Program in Molecular Medicine, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Qingbo Chen
- Program in Molecular Medicine, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Hannah L Pepper
- Aging + Cardiovascular Discovery Center, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, USA
| | - Hafsah Ahmad
- Aging + Cardiovascular Discovery Center, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, USA
| | - Alexander Boucher
- Program in Molecular Medicine, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Shelagh M Fluharty
- Program in Molecular Medicine, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Te-Yueh Lin
- Program in Molecular Medicine, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Anoushka Lotun
- Program in Molecular Medicine, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Jessica Peura
- Division of Hematology-Oncology, Department of Medicine, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Sophie Trefely
- Department of Cancer Biology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
- Abramson Family Cancer Research Institute, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
| | - Courtney R Green
- Department of Bioengineering, University of California, San Diego, La Jolla, CA, USA
| | - Paula Vo
- Program in Molecular Medicine, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Clay F Semenkovich
- Division of Endocrinology, Metabolism and Lipid Research, Washington University School of Medicine, St. Louis, MO, USA
| | - Jason R Pitarresi
- Division of Hematology-Oncology, Department of Medicine, University of Massachusetts Chan Medical School, Worcester, MA, USA
- Department of Molecular, Cell and Cancer Biology, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Jessica B Spinelli
- Program in Molecular Medicine, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Ozkan Aydemir
- Program in Molecular Medicine, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Christian M Metallo
- Department of Bioengineering, University of California, San Diego, La Jolla, CA, USA
- Molecular and Cellular Biology Laboratory, The Salk Institute for Biological Studies, La Jolla, CA, USA
| | | | - Cholsoon Jang
- Department of Biological Chemistry, University of California Irvine, Irvine, CA, USA
| | - Nathaniel W Snyder
- Aging + Cardiovascular Discovery Center, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, USA
| | - Kathryn E Wellen
- Department of Cancer Biology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
- Abramson Family Cancer Research Institute, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
| | - David A Guertin
- Program in Molecular Medicine, University of Massachusetts Chan Medical School, Worcester, MA, USA.
- Department of Molecular, Cell and Cancer Biology, University of Massachusetts Chan Medical School, Worcester, MA, USA.
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4
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Zuccaro MV, LeDuc CA, Thaker VV. Updates on Rare Genetic Variants, Genetic Testing, and Gene Therapy in Individuals With Obesity. Curr Obes Rep 2024; 13:626-641. [PMID: 38822963 PMCID: PMC11694263 DOI: 10.1007/s13679-024-00567-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 04/10/2024] [Indexed: 06/03/2024]
Abstract
PURPOSE OF REVIEW The goal of this paper is to aggregate information on monogenic contributions to obesity in the past five years and to provide guidance for genetic testing in clinical care. RECENT FINDINGS Advances in sequencing technologies, increasing awareness, access to testing, and new treatments have increased the utilization of genetics in clinical care. There is increasing recognition of the prevalence of rare genetic obesity from variants with mean allele frequency < 5% -new variants in known genes as well as identification of novel genes- causing monogenic obesity. While most of these genes are in the leptin melanocortin pathway, those in adipocytes may also contribute. Common variants may contribute either to higher lifetime tendency for weight gain or provide protection from monogenic obesity. While specific genetic mutations are rare, these segregate in individuals with early-onset severe obesity; thus, collectively genetic etiologies are not as rare. Some genetic conditions are amenable to targeted treatment. Research into the discovery of novel genetic causes as well as targeted treatment is growing over time. The utility of therapeutic strategies based on the genetic risk of obesity is an advancing frontier.
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Affiliation(s)
- Michael V Zuccaro
- Division of Genetics and Genomics, Department of Pediatrics, Boston Children's Hospital, Harvard Medical School, Boston, MA, 02115, United States
| | - Charles A LeDuc
- Division of Molecular Genetics, Department of Pediatrics, Columbia University Irving Medical Center, 1150, St. Nicholas Avenue, NY 10032, United States
- Vagelos College of Physicians and Surgeons, Columbia University, New York, NY, 10032, United States
| | - Vidhu V Thaker
- Division of Molecular Genetics, Department of Pediatrics, Columbia University Irving Medical Center, 1150, St. Nicholas Avenue, NY 10032, United States.
- Vagelos College of Physicians and Surgeons, Columbia University, New York, NY, 10032, United States.
- Division of Pediatric Endocrinology, Department of Pediatrics, Columbia University Irving Medical Center, New York, NY, 10032, United States.
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5
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Ouyang H, Zhang Y, Zhu Y, Gong T, Zhang Z, Fu Y. Adipocyte-targeted celastrol delivery via biguanide-modified micelles improves treatment of obesity in DIO mice. J Mater Chem B 2024; 12:7905-7914. [PMID: 39028265 DOI: 10.1039/d4tb00777h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/20/2024]
Abstract
Obesity has emerged as a significant global health burden, exacerbated by serious side effects associated with existing anti-obesity medications. Celastrol (CLT) holds promise for weight loss but encounters challenges related to poor solubility and systemic toxicity. Here, we present chondroitin sulfate (CS)-derived micelles engineered for adipocyte-specific targeting, aiming to enhance the therapeutic potential of CLT while minimizing its systemic toxicity. To further enhance adipocyte affinity, we introduced a biguanide moiety into a micellar vehicle. CS is sequentially modified with hydrophilic metformin and hydrophobic 4-aminophenylboronic acid pinacol ester (PBE), resulting in the self-assembly of CLT-encapsulated micelles (MET-CS-PBE@CLT). This innovative design imparts amphiphilicity via the PBE moieties while ensuring the outward exposure of hydrophilic metformin moieties, facilitating active interactions with adipocytes. In vitro studies confirmed the enhanced uptake of MET-CS-PBE@CLT micelles by adipocytes, while in vivo studies demonstrated increased distribution within adipose tissues. In a diet-induced obese mouse model, MET-CS-PBE@CLT exhibited remarkable efficacy in weight loss without affecting food intake. This pioneering strategy offers a promising, low-risk, and highly effective solution to address the global obesity epidemic.
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Affiliation(s)
- Hongling Ouyang
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Sichuan Province, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China.
| | - Yunxiao Zhang
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Sichuan Province, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China.
| | - Yueting Zhu
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Sichuan Province, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China.
| | - Tao Gong
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Sichuan Province, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China.
| | - Zhirong Zhang
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Sichuan Province, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China.
| | - Yao Fu
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Sichuan Province, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China.
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6
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Park MJ, Lee J, Bagon BB, Matienzo ME, Lim S, Kim K, Lee CM, Wu J, Kim DI. N G ,N G -Dimethylarginine Dimethylaminohydrolase 1 Expression Is Dispensable for Cold- or Diet-Induced Thermogenesis. Adv Biol (Weinh) 2024; 8:e2300192. [PMID: 38164809 DOI: 10.1002/adbi.202300192] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Revised: 12/18/2023] [Indexed: 01/03/2024]
Abstract
The strategy to activate thermogenic adipocytes has therapeutic potential to overcome obesity as they dissipate surplus energy as heat through various mechanisms. NG,NG-dimethylarginine dimethylaminohydrolases (DDAHs) are enzymes involved in the nitric oxide-protein kinase G signaling axis which increases thermogenic gene expression. However, the role of DDAHs in thermogenic adipocytes has not been elucidated. The adipocyte-specific Ddah1 knockout mice are generated by crossing Ddah1fl/fl mice with adiponectin Cre recombinase mice. Adipocyte-specific DDAH1 overexpressing mice are generated using adeno-associated virus-double-floxed inverse open reading frame (AAV-DIO) system. These mice are analyzed under basal, cold exposure, or high-fat diet (HFD) conditions. Primary inguinal white adipose tissue cells from adipocyte-specific Ddah1 knockout mice expressed comparable amounts of Ucp1 mRNA. Adipocyte-specific DDAH1 overexpressing mice do not exhibit enhanced activation of thermogenic adipocytes. In addition, when these mice are exposed to cold environment or fed an HFD, their body temperature/weight and thermogenesis-related gene and protein expressions are unchanged. These findings indicate that DDAH1 does not play a role in either cold- or diet-induced thermogenesis. Therefore, adipocyte targeting DDAH1 gene therapy for the treatment of obesity is unlikely to be effective.
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Affiliation(s)
- Min-Jung Park
- Department of Veterinary Physiology, College of Veterinary Medicine, Chonnam National University, Gwangju, 61186, South Korea
| | - Junhyeong Lee
- Department of Veterinary Physiology, College of Veterinary Medicine, Chonnam National University, Gwangju, 61186, South Korea
- College of Veterinary Medicine and BK21 FOUR Program, Chonnam National University, Gwangju, 61186, South Korea
| | - Bernadette B Bagon
- Department of Veterinary Physiology, College of Veterinary Medicine, Chonnam National University, Gwangju, 61186, South Korea
| | - Merc Emil Matienzo
- Department of Veterinary Physiology, College of Veterinary Medicine, Chonnam National University, Gwangju, 61186, South Korea
- College of Veterinary Medicine and BK21 FOUR Program, Chonnam National University, Gwangju, 61186, South Korea
| | - Sangyi Lim
- Department of Veterinary Physiology, College of Veterinary Medicine, Chonnam National University, Gwangju, 61186, South Korea
- College of Veterinary Medicine and BK21 FOUR Program, Chonnam National University, Gwangju, 61186, South Korea
| | - Keon Kim
- College of Veterinary Medicine and BK21 FOUR Program, Chonnam National University, Gwangju, 61186, South Korea
- Department of Veterinary Internal Medicine, College of Veterinary Medicine, Chonnam National University, Gwangju, 61186, South Korea
| | - Chang-Min Lee
- College of Veterinary Medicine and BK21 FOUR Program, Chonnam National University, Gwangju, 61186, South Korea
- Department of Veterinary Internal Medicine, College of Veterinary Medicine, Chonnam National University, Gwangju, 61186, South Korea
| | - Jun Wu
- Life Sciences Institute, University of Michigan, Ann Arbor, MI, 48109, USA
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI, 48109, USA
| | - Dong-Il Kim
- Department of Veterinary Physiology, College of Veterinary Medicine, Chonnam National University, Gwangju, 61186, South Korea
- College of Veterinary Medicine and BK21 FOUR Program, Chonnam National University, Gwangju, 61186, South Korea
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7
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Haley JA, Jang C, Guertin DA. A new era of understanding in vivo metabolic flux in thermogenic adipocytes. Curr Opin Genet Dev 2023; 83:102112. [PMID: 37703635 PMCID: PMC10840980 DOI: 10.1016/j.gde.2023.102112] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2023] [Revised: 07/25/2023] [Accepted: 08/13/2023] [Indexed: 09/15/2023]
Abstract
Nonshivering thermogenesis by brown adipose tissue (BAT) is an adaptive mechanism for maintaining body temperature in cold environments. BAT is critical in rodents and human infants and has substantial influence on adult human metabolism. Stimulating BAT therapeutically is also being investigated as a strategy against metabolic diseases because of its ability to function as a catabolic sink. Thus, understanding how brown adipocytes and the related brite/beige adipocytes use nutrients to fuel their demanding metabolism has both basic and translational implications. Recent advances in mass spectrometry and isotope tracing are improving the ability to study metabolic flux in vivo. Here, we review how such strategies are advancing our understanding of adipocyte thermogenesis and conclude with key future questions.
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Affiliation(s)
- John A Haley
- Program in Molecular Medicine, UMass Chan Medical School, Worcester, MA, USA
| | - Cholsoon Jang
- Department of Biological Chemistry, University of California Irvine, Irvine, CA, USA
| | - David A Guertin
- Program in Molecular Medicine, UMass Chan Medical School, Worcester, MA, USA.
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8
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Tsuji T, Zhang Y, Tseng YH. Generation of Brown Fat-Specific Knockout Mice Using a Combined Cre-LoxP, CRISPR-Cas9, and Adeno-Associated Virus Single-Guide RNA System. J Vis Exp 2023:10.3791/65083. [PMID: 37036212 PMCID: PMC10403816 DOI: 10.3791/65083] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/11/2023] Open
Abstract
Brown adipose tissue (BAT) is an adipose depot specialized in energy dissipation that can also serve as an endocrine organ via the secretion of bioactive molecules. The creation of BAT-specific knockout mice is one of the most popular approaches for understanding the contribution of a gene of interest to BAT-mediated energy regulation. The conventional gene targeting strategy utilizing the Cre-LoxP system has been the principal approach to generate tissue-specific knockout mice. However, this approach is time-consuming and tedious. Here, we describe a protocol for the rapid and efficient knockout of a gene of interest in BAT using a combined Cre-LoxP, CRISPR-Cas9, and adeno-associated virus (AAV) single-guide RNA (sgRNA) system. The interscapular BAT is located in the deep layer between the muscles. Thus, the BAT must be exposed in order to inject the AAV precisely and directly into the BAT within the visual field. Appropriate surgical handling is crucial to prevent damage to the sympathetic nerves and vessels, such as the Sultzer's vein that connects to the BAT. To minimize tissue damage, there is a critical need to understand the three-dimensional anatomical location of the BAT and the surgical skills required in the technical steps. This protocol highlights the key technical procedures, including the design of sgRNAs targeting the gene of interest, the preparation of AAV-sgRNA particles, and the surgery for the direct microinjection of AAV into both BAT lobes for generating BAT-specific knockout mice, which can be broadly applied to study the biological functions of genes in BAT.
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Affiliation(s)
- Tadataka Tsuji
- Section on Integrative Physiology and Metabolism, Research Division, Joslin Diabetes Center, Harvard Medical School
| | - Yang Zhang
- Section on Integrative Physiology and Metabolism, Research Division, Joslin Diabetes Center, Harvard Medical School
| | - Yu-Hua Tseng
- Section on Integrative Physiology and Metabolism, Research Division, Joslin Diabetes Center, Harvard Medical School;
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9
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Genetic advancements in obesity management and CRISPR-Cas9-based gene editing system. Mol Cell Biochem 2023; 478:491-501. [PMID: 35909208 DOI: 10.1007/s11010-022-04518-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Accepted: 06/24/2022] [Indexed: 10/16/2022]
Abstract
Human genome research has reached new heights in the recent decade thanks to a major advance in genome editing. Genome editing enables scientists to understand better the functions of a single gene and its impact on a wide range of diseases. In brief, genome editing is a technique for introducing alterations into specific DNA sequences, such as insertions, deletions, or base substitutions. Several methods are adopted to perform genome editing and clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated nuclease 9 (Cas9) systems. Unfortunately, despite substantial progress in understanding the molecular pathways behind obesity, anti-obesity medications are now ineffective. If you are obese, a 10% weight decrease would be preferable to healthy body weight for most people. CRISPR-Cas9, on the other hand, has been shown to reduce body weight by an astonishing 20%. Hence, this updated review elaborates on the molecular basis of obesity, risk factors, types of gene therapy, possible mechanisms, and advantages of the CRISPR-Cas9 system over other methods.
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10
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Xue K, Wu D, Qiu Y. Specific and efficient gene knockout and overexpression in mouse interscapular brown adipocytes in vivo. STAR Protoc 2022; 3:101895. [PMID: 36595932 PMCID: PMC9722717 DOI: 10.1016/j.xpro.2022.101895] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Revised: 10/22/2022] [Accepted: 11/09/2022] [Indexed: 12/03/2022] Open
Abstract
The classical Cre-LoxP system is time consuming. Here we detail a protocol that leverages Rosa26-LSL-Cas9;Adiponectin-Cre mice to restrict Cas9 expression in adipocytes. This enables specific deletion of target genes in brown adipocytes within 6 weeks by local injection of AAV-sgRNA into interscapular brown adipose tissue. We also describe an adiponectin-promoter-driven AAV vector to express sgRNA-resistant cDNA-encoded protein for subsequent rescue. This protocol thus provides an efficient means to specifically knockout and overexpress genes in brown adipocytes in vivo. For complete details on the use and execution of this protocol, please refer to Xue et al. (2022).1.
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Affiliation(s)
- Kaili Xue
- Institute of Molecular Medicine, Beijing Key Laboratory of Cardiometabolic Molecular Medicine, College of Future Technology, Peking University, Beijing 100871, China,Corresponding author
| | - Dongmei Wu
- Institute of Molecular Medicine, Beijing Key Laboratory of Cardiometabolic Molecular Medicine, College of Future Technology, Peking University, Beijing 100871, China,Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China
| | - Yifu Qiu
- Institute of Molecular Medicine, Beijing Key Laboratory of Cardiometabolic Molecular Medicine, College of Future Technology, Peking University, Beijing 100871, China,Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China,Corresponding author
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