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Sucquart IE, Coyle C, Rodriguez Paris V, Prescott M, Glendining KA, Potapov K, Begg DP, Gilchrist RB, Walters KA, Campbell RE. Investigating GABA Neuron-Specific Androgen Receptor Knockout in two Hyperandrogenic Models of PCOS. Endocrinology 2024; 165:bqae060. [PMID: 38788194 DOI: 10.1210/endocr/bqae060] [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: 02/24/2024] [Revised: 05/20/2024] [Accepted: 05/20/2024] [Indexed: 05/26/2024]
Abstract
Androgen excess is a hallmark feature of polycystic ovary syndrome (PCOS), the most common form of anovulatory infertility. Clinical and preclinical evidence links developmental or chronic exposure to hyperandrogenism with programming and evoking the reproductive and metabolic traits of PCOS. While critical androgen targets remain to be determined, central GABAergic neurons are postulated to be involved. Here, we tested the hypothesis that androgen signaling in GABAergic neurons is critical in PCOS pathogenesis in 2 well-characterized hyperandrogenic mouse models of PCOS. Using cre-lox transgenics, GABA-specific androgen receptor knockout (GABARKO) mice were generated and exposed to either acute prenatal androgen excess (PNA) or chronic peripubertal androgen excess (PPA). Females were phenotyped for reproductive and metabolic features associated with each model and brains of PNA mice were assessed for elevated GABAergic input to gonadotropin-releasing hormone (GnRH) neurons. Reproductive and metabolic dysfunction induced by PPA, including acyclicity, absence of corpora lutea, obesity, adipocyte hypertrophy, and impaired glucose homeostasis, was not different between GABARKO and wild-type (WT) mice. In PNA mice, acyclicity remained in GABARKO mice while ovarian morphology and luteinizing hormone secretion was not significantly impacted by PNA or genotype. However, PNA predictably increased the density of putative GABAergic synapses to GnRH neurons in adult WT mice, and this PNA-induced plasticity was absent in GABARKO mice. Together, these findings suggest that while direct androgen signaling in GABA neurons is largely not required for the development of PCOS-like traits in androgenized models of PCOS, developmental programming of GnRH neuron innervation is dependent upon androgen signaling in GABA neurons.
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Affiliation(s)
- Irene E Sucquart
- Fertility & Research Centre, School of Clinical Medicine, University of New South Wales Sydney, Randwick, NSW 2031, Australia
| | - Chris Coyle
- Centre of Neuroendocrinology and Department of Physiology, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand 9054
| | - Valentina Rodriguez Paris
- Fertility & Research Centre, School of Clinical Medicine, University of New South Wales Sydney, Randwick, NSW 2031, Australia
- School of Biomedical Sciences, University of New South Wales Sydney, Randwick, NSW 2052, Australia
| | - Melanie Prescott
- Centre of Neuroendocrinology and Department of Physiology, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand 9054
| | - Kelly A Glendining
- Centre of Neuroendocrinology and Department of Physiology, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand 9054
| | - Kyoko Potapov
- Centre of Neuroendocrinology and Department of Physiology, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand 9054
| | - Denovan P Begg
- Department of Behavioural Neuroscience, School of Psychology, University of New South Wales Sydney, Randwick, NSW, Australia
| | - Robert B Gilchrist
- Fertility & Research Centre, School of Clinical Medicine, University of New South Wales Sydney, Randwick, NSW 2031, Australia
| | - Kirsty A Walters
- Fertility & Research Centre, School of Clinical Medicine, University of New South Wales Sydney, Randwick, NSW 2031, Australia
| | - Rebecca E Campbell
- Centre of Neuroendocrinology and Department of Physiology, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand 9054
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Kerbus RI, Decourt C, Inglis MA, Campbell RE, Anderson GM. Androgen receptor actions on AgRP neurons are not a major cause of reproductive and metabolic impairments in peripubertally androgenized mice. J Neuroendocrinol 2024; 36:e13370. [PMID: 38344844 DOI: 10.1111/jne.13370] [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: 07/15/2023] [Revised: 12/22/2023] [Accepted: 01/14/2024] [Indexed: 03/08/2024]
Abstract
Excess levels of circulating androgens during prenatal or peripubertal development are an important cause of polycystic ovary syndrome (PCOS), with the brain being a key target. Approximately half of the women diagnosed with PCOS also experience metabolic syndrome; common features including obesity, insulin resistance and hyperinsulinemia. Although a large amount of clinical and preclinical evidence has confirmed this relationship between androgens and the reproductive and metabolic features of PCOS, the mechanisms by which androgens cause this dysregulation are unknown. Neuron-specific androgen receptor knockout alleviates some PCOS-like features in a peripubertal dihydrotestosterone (DHT) mouse model, but the specific neuronal populations mediating these effects are undefined. A candidate population is the agouti-related peptide (AgRP)-expressing neurons, which are important for both reproductive and metabolic function. We used a well-characterised peripubertal androgenized mouse model and Cre-loxP transgenics to investigate whether deleting androgen receptors specifically from AgRP neurons can alleviate the induced reproductive and metabolic dysregulation. Androgen receptors were co-expressed in 66% of AgRP neurons in control mice, but only in <2% of AgRP neurons in knockout mice. The number of AgRP neurons was not altered by the treatments. Only 20% of androgen receptor knockout mice showed rescue of DHT-induced androgen-induced anovulation and acyclicity. Furthermore, androgen receptor knockout did not rescue metabolic dysfunction (body weight, adiposity or glucose and insulin tolerance). While we cannot rule out developmental compensation in our model, these results suggest peripubertal androgen excess does not markedly influence Agrp expression and does not dysregulate reproductive and metabolic function through direct actions of androgens onto AgRP neurons.
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Affiliation(s)
- Romy I Kerbus
- Centre for Neuroendocrinology and Department of Anatomy, University of Otago School of Biomedical Sciences, Dunedin, New Zealand
| | - Caroline Decourt
- Centre for Neuroendocrinology and Department of Anatomy, University of Otago School of Biomedical Sciences, Dunedin, New Zealand
| | - Megan A Inglis
- Centre for Neuroendocrinology and Department of Anatomy, University of Otago School of Biomedical Sciences, Dunedin, New Zealand
| | - Rebecca E Campbell
- Department of Physiology, University of Otago School of Biomedical Sciences, Dunedin, New Zealand
| | - Greg M Anderson
- Centre for Neuroendocrinology and Department of Anatomy, University of Otago School of Biomedical Sciences, Dunedin, New Zealand
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Wang K, Li Y, Chen Y. Androgen excess: a hallmark of polycystic ovary syndrome. Front Endocrinol (Lausanne) 2023; 14:1273542. [PMID: 38152131 PMCID: PMC10751361 DOI: 10.3389/fendo.2023.1273542] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/06/2023] [Accepted: 11/22/2023] [Indexed: 12/29/2023] Open
Abstract
Polycystic ovarian syndrome (PCOS) is a metabolic, reproductive, and psychological disorder affecting 6-20% of reproductive women worldwide. However, there is still no cure for PCOS, and current treatments primarily alleviate its symptoms due to a poor understanding of its etiology. Compelling evidence suggests that hyperandrogenism is not just a primary feature of PCOS. Instead, it may be a causative factor for this condition. Thus, figuring out the mechanisms of androgen synthesis, conversion, and metabolism is relatively important. Traditionally, studies of androgen excess have largely focused on classical androgen, but in recent years, adrenal-derived 11-oxygenated androgen has also garnered interest. Herein, this Review aims to investigate the origins of androgen excess, androgen synthesis, how androgen receptor (AR) signaling mediates adverse PCOS traits, and the role of 11-oxygenated androgen in the pathophysiology of PCOS. In addition, it provides therapeutic strategies targeting hyperandrogenism in PCOS.
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Affiliation(s)
- Kexin Wang
- The Second School of Clinical Medicine, Zhejiang Chinese Medical University, Hangzhou, China
| | - Yanhua Li
- Department of General Practice, The Second Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou, China
| | - Yu Chen
- The Second School of Clinical Medicine, Zhejiang Chinese Medical University, Hangzhou, China
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Cutia CA, Leverton LK, Weis KE, Raetzman LT, Christian-Hinman CA. Female-specific pituitary gonadotrope dysregulation in mice with chronic focal epilepsy. Exp Neurol 2023; 364:114389. [PMID: 36990138 PMCID: PMC10149611 DOI: 10.1016/j.expneurol.2023.114389] [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: 01/14/2023] [Revised: 02/19/2023] [Accepted: 03/21/2023] [Indexed: 03/30/2023]
Abstract
Gonadotropin hormone release from the anterior pituitary is critical to regulating reproductive endocrine function. Clinical evidence has documented that people with epilepsy display altered levels of gonadotropin hormones, both acutely following seizures and chronically. Despite this relationship, pituitary function remains a largely understudied avenue in preclinical epilepsy research. Recently, we showed that females in the intrahippocampal kainic acid (IHKA) mouse model of temporal lobe epilepsy displayed changes in pituitary expression of gonadotropin hormone and gonadotropin-releasing hormone (GnRH) receptor genes. Circulating gonadotropin hormone levels, however, have yet to be measured in an animal model of epilepsy. Here, we evaluated the circulating levels of luteinizing hormone (LH) and follicle-stimulating hormone (FSH), GnRH receptor (Gnrhr) gene expression, and sensitivity to exogenous GnRH in IHKA males and females. Although no changes in overall dynamics of pulsatile patterns of LH release were found in IHKA mice of either sex, estrus vs. diestrus changes in basal and mean LH levels were larger in IHKA females with prolonged, disrupted estrous cycles. In addition, IHKA females displayed increased pituitary sensitivity to GnRH and higher Gnrhr expression. The hypersensitivity to GnRH was observed on diestrus, but not estrus. Chronic seizure severity was not found to be correlated with LH parameters, and FSH levels were unchanged in IHKA mice. These results indicate that although there are changes in pituitary gene expression and sensitivity to GnRH in IHKA females, there may also be compensatory mechanisms that aid in maintaining gonadotropin release in the state of chronic epilepsy in this model.
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Affiliation(s)
- Cathryn A Cutia
- Neuroscience Program, University of Illinois Urbana-Champaign, Urbana, IL 61801, USA
| | - Leanna K Leverton
- Department of Molecular and Integrative Physiology, University of Illinois Urbana-Champaign, Urbana, IL 61801, USA
| | - Karen E Weis
- Department of Molecular and Integrative Physiology, University of Illinois Urbana-Champaign, Urbana, IL 61801, USA
| | - Lori T Raetzman
- Neuroscience Program, University of Illinois Urbana-Champaign, Urbana, IL 61801, USA; Department of Molecular and Integrative Physiology, University of Illinois Urbana-Champaign, Urbana, IL 61801, USA
| | - Catherine A Christian-Hinman
- Neuroscience Program, University of Illinois Urbana-Champaign, Urbana, IL 61801, USA; Department of Molecular and Integrative Physiology, University of Illinois Urbana-Champaign, Urbana, IL 61801, USA; Beckman Institute for Advanced Science and Technology, University of Illinois Urbana-Champaign, Urbana, IL 61801, USA.
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Pei Y, Risal S, Jiang H, Lu H, Lindgren E, Stener-Victorin E, Deng Q. Transcriptomic survey of key reproductive and metabolic tissues in mouse models of polycystic ovary syndrome. Commun Biol 2023; 6:69. [PMID: 36653487 PMCID: PMC9849269 DOI: 10.1038/s42003-022-04362-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Accepted: 12/09/2022] [Indexed: 01/19/2023] Open
Abstract
Excessive androgen production and obesity are key to polycystic ovary syndrome (PCOS) pathogenesis. Prenatal androgenized (PNA), peripubertal androgenized, and overexpression of nerve growth factor in theca cells (17NF) are commonly used PCOS-like mouse models and diet-induced maternal obesity model is often included for comparsion. To reveal the molecular features of these models, we have performed transcriptome survey of the hypothalamus, adipose tissue, ovary and metaphase II (MII) oocytes. The largest number of differentially expressed genes (DEGs) is found in the ovaries of 17NF and in the adipose tissues of peripubertal androgenized models. In contrast, hypothalamus is most affected in PNA and maternal obesity models suggesting fetal programming effects. The Ms4a6e gene, membrane-spanning 4-domains subfamily A member 6E, a DEG identified in the adipose tissue in all mouse models is also differently expressed in adipose tissue of women with PCOS, highlighting a conserved disease function. Our comprehensive transcriptomic profiling of key target tissues involved in PCOS pathology highlights the effects of developmental windows for androgen exposure and maternal obesity, and provides unique resource to investigate molecular mechanisms underlying PCOS pathogenesis.
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Affiliation(s)
- Yu Pei
- grid.4714.60000 0004 1937 0626Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden ,grid.24381.3c0000 0000 9241 5705Center for molecular medicine, Karolinska University Hospital, Stockholm, Sweden
| | - Sanjiv Risal
- grid.4714.60000 0004 1937 0626Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Hong Jiang
- grid.4714.60000 0004 1937 0626Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Haojiang Lu
- grid.4714.60000 0004 1937 0626Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Eva Lindgren
- grid.4714.60000 0004 1937 0626Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Elisabet Stener-Victorin
- grid.4714.60000 0004 1937 0626Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Qiaolin Deng
- grid.4714.60000 0004 1937 0626Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden ,grid.24381.3c0000 0000 9241 5705Center for molecular medicine, Karolinska University Hospital, Stockholm, Sweden
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Stener-Victorin E. Update on Animal Models of Polycystic Ovary Syndrome. Endocrinology 2022; 163:6750034. [PMID: 36201611 PMCID: PMC9631972 DOI: 10.1210/endocr/bqac164] [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: 07/02/2022] [Indexed: 11/19/2022]
Abstract
Polycystic ovary syndrome (PCOS) is a complex disease affecting up to 15% of women of reproductive age. Women with PCOS suffer from reproductive dysfunctions with excessive androgen secretion and irregular ovulation, leading to reduced fertility and pregnancy complications. The syndrome is associated with a wide range of comorbidities including type 2 diabetes, obesity, and psychiatric disorders. Despite the high prevalence of PCOS, its etiology remains unclear. To understand the pathophysiology of PCOS, how it is inherited, and how to predict PCOS, and prevent and treat women with the syndrome, animal models provide an important approach to answering these fundamental questions. This minireview summarizes recent investigative efforts on PCOS-like rodent models aiming to define underlying mechanisms of the disease and provide guidance in model selection. The focus is on new genetic rodent models, on a naturally occurring rodent model, and provides an update on prenatal and peripubertal exposure models.
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Affiliation(s)
- Elisabet Stener-Victorin
- Correspondence: Elisabet Stener-Victorin, PhD, Professor, Department of Physiology and Pharmacology, Karolinska Institutet, Biomedicum, B5, 171 77 Stockholm, Sweden.
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Bhattarai P, Rijal S, Bhattarai JP, Cho DH, Han SK. Suppression of neurotransmission on gonadotropin-releasing hormone neurons in letrozole-induced polycystic ovary syndrome: A mouse model. Front Endocrinol (Lausanne) 2022; 13:1059255. [PMID: 36699037 PMCID: PMC9868609 DOI: 10.3389/fendo.2022.1059255] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/01/2022] [Accepted: 12/08/2022] [Indexed: 01/11/2023] Open
Abstract
OBJECTIVE Polycystic ovarian syndrome (PCOS) is a heterogeneous endocrine disorder in reproductive-age women, characterized by the accretion of small cystic follicles in the ovary associated with chronic anovulation and overproduction of androgens. Ovarian function in all mammals is controlled by gonadotropin-releasing hormone (GnRH) neurons, which are the central regulator of the hypothalamic-pituitary-gonadal (HPG) axis. However, the impact on the neurotransmitter system regulating GnRH neuronal function in the letrozole-induced PCOS mouse model remains unclear. METHODS In this study, we compared the response of various neurotransmitters and neurosteroids regulating GnRH neuronal activities between letrozole-induced PCOS and normal mice via electrophysiological techniques. RESULTS Response to neurotransmitter systems like GABAergic, glutamatergic and kisspeptinergic were suppressed in letrozole-fed compared to normal mice. In addition, neurosteroids tetrahydrodeoxycorticosterone (THDOC) and 4,5,6,7-tetrahydroisoxazolo[5,4-c] pyridine-3-ol (THIP) mediated response on GnRH neurons were significantly smaller on letrozole-fed mice compared to normal mice. Furthermore, we also found that letrozole-fed mice showed irregularity in the estrous cycle, increased body weight, and anovulation in female mice. CONCLUSION These findings suggest that PCOS is an endocrine disorder that may directly affect the neurotransmitter system regulating GnRH neuronal activity at the hypothalamic level and impact reproductive physiology.
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Affiliation(s)
- Pravin Bhattarai
- Department of Oral Physiology, School of Dentistry and Institute of Oral Bioscience, Jeonbuk National University, Jeonju, South Korea
| | - Santosh Rijal
- Department of Oral Physiology, School of Dentistry and Institute of Oral Bioscience, Jeonbuk National University, Jeonju, South Korea
| | - Janardhan P. Bhattarai
- Department of Neuroscience, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, United States
| | - Dong Hyu Cho
- Department of Obstetrics and Gynecology, Jeonbuk National University Medical School, Research Institute of Clinical Medicine of Jeonbuk National University-Biomedical Research Institute of Jeonbuk National University Hospital, Jeonju, South Korea
- *Correspondence: Dong Hyu Cho, ; Seong Kyu Han,
| | - Seong Kyu Han
- Department of Oral Physiology, School of Dentistry and Institute of Oral Bioscience, Jeonbuk National University, Jeonju, South Korea
- *Correspondence: Dong Hyu Cho, ; Seong Kyu Han,
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Feng M, Divall S, Jones D, Ubba V, Fu X, Yang L, Wang H, Yang X, Wu S. Comparison of Reproductive Function Between Normal and Hyperandrogenemia Conditions in Female Mice With Deletion of Hepatic Androgen Receptor. Front Endocrinol (Lausanne) 2022; 13:868572. [PMID: 35757434 PMCID: PMC9218244 DOI: 10.3389/fendo.2022.868572] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Accepted: 05/05/2022] [Indexed: 11/13/2022] Open
Abstract
Obesity, altered glucose homeostasis, hyperinsulinism, and reproductive dysfunction develops in female humans and mammals with hyperandrogenism. We previously reported that low dose dihydrotestosterone (DHT) administration results in metabolic and reproductive dysfunction in the absence of obesity in female mice, and conditional knock-out of the androgen receptor (Ar) in the liver (LivARKO) protects female mice from DHT-induced glucose intolerance and hyperinsulinemia. Since altered metabolic function will regulate reproduction, and liver plays a pivotal role in the reversible regulation of reproductive function, we sought to determine the reproductive phenotype of LivARKO mice under normal and hyperandrogenemic conditions. Using Cre/Lox technology, we deleted the Ar in the liver, and we observed LivARKO female mice have normal puberty timing, cyclicity and reproductive function. After DHT treatment, like control mice, LivARKO experience altered estrous cycling, reduced numbers of corpus lutea, and infertility. Liver Ar is not involved in hyperandrogenemia-induced reproductive dysfunction. The reproductive dysfunction in the DHT-treated LivARKO lean females with normal glucose homeostasis indicates that androgen-induced reproductive dysfunction is independent from metabolic dysfunction.
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Affiliation(s)
- Mingxiao Feng
- Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Sara Divall
- Department of Pediatrics, Seattle’s Children’s Hospital, University of Washington, Seattle, WA, United States
| | - Dustin Jones
- Department of Cellular and Molecular Physiology, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Vaibhave Ubba
- Department of Cardiovascular Sciences/Center for Metabolic Disease Research, Temple University School of Medicine, Philadelphia, PA, United States
| | - Xiaomin Fu
- Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, MD, United States
- Department of Endocrinology, The First Medical Center, Chinese PLA General Hospital, Beijing, China
| | - Ling Yang
- Medical Genetics and Molecular Biochemistry, Temple University School of Medicine, Philadelphia, PA, United States
| | - Hong Wang
- Department of Cardiovascular Sciences/Center for Metabolic Disease Research, Temple University School of Medicine, Philadelphia, PA, United States
| | - Xiaofeng Yang
- Department of Cardiovascular Sciences/Center for Metabolic Disease Research, Temple University School of Medicine, Philadelphia, PA, United States
| | - Sheng Wu
- Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, MD, United States
- Department of Cardiovascular Sciences/Center for Metabolic Disease Research, Temple University School of Medicine, Philadelphia, PA, United States
- *Correspondence: Sheng Wu,
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