1
|
Sathyanarayanan H, Sundaram M. Study of Association of Dyslipidemia in Male Androgenetic Alopecia Patients in a Tertiary Care Hospital. Cureus 2024; 16:e51741. [PMID: 38318584 PMCID: PMC10840442 DOI: 10.7759/cureus.51741] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/03/2024] [Indexed: 02/07/2024] Open
Abstract
INTRODUCTION Androgenetic alopecia (AGA) is a hereditary and androgen-dependent progressive thinning of the scalp hair in a defined pattern. Several studies have reported an association between dyslipidemia and AGA. However, scarce data is available on association between severity of AGA and dyslipidemia. Hence, we performed a study to assess the clinical, epidemiological profile in male AGA patients and to compare lipid parameters among AGA cases and non-AGA controls to evaluate dyslipidemia association. MATERIALS AND METHODS This is a prospective case-control study included 108 age-matched AGA cases and non-AGA controls between 19-40 years. AGA was clinically diagnosed, and grading was done according to Norwood-Hamilton Classification. Fasting Lipid parameters for both cases and controls were determined using standard laboratory methods. RESULTS Among the cases and controls, the mean age was 26.20±5.353 years. There was a statistically significant association between AGA and mean total cholesterol (TC) (P<0.001), mean high-density lipoprotein (HDL) (P<0.001), mean low-density lipoprotein (LDL) (P<0.001) and mean cholesterol/HDL ratio (P<0.001), except for mean triglycerides (TG) (P=0.443). Grade 4 was the commonest grading (20.4%). As the severity of AGA increased, the lipid parameters were significantly deranged. It was evident Grade 4 onwards with statistically significant derangement in TC (P<0.001), TG (P=0.005), HDL (P=0.002), LDL (P <0.001) and cholesterol/HDL(P<0.001). CONCLUSIONS AGA was found to be significantly associated with dyslipidemia and more common among severe grades. AGA could be a cutaneous marker of underlying systemic illness. Early screening for dyslipidemia is beneficial in patients with AGA.
Collapse
Affiliation(s)
| | - Murugan Sundaram
- Dermatology, Sri Ramachandra Institute of Higher Education and Research, Chennai, IND
| |
Collapse
|
2
|
Yang F, Xiao Y, Ding JH, Jin X, Ma D, Li DQ, Shi JX, Huang W, Wang YP, Jiang YZ, Shao ZM. Ferroptosis heterogeneity in triple-negative breast cancer reveals an innovative immunotherapy combination strategy. Cell Metab 2023; 35:84-100.e8. [PMID: 36257316 DOI: 10.1016/j.cmet.2022.09.021] [Citation(s) in RCA: 139] [Impact Index Per Article: 139.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Revised: 07/24/2022] [Accepted: 09/21/2022] [Indexed: 01/20/2023]
Abstract
Treatment of triple-negative breast cancer (TNBC) remains challenging. Deciphering the orchestration of metabolic pathways in regulating ferroptosis will provide new insights into TNBC therapeutic strategies. Here, we integrated the multiomics data of our large TNBC cohort (n = 465) to develop the ferroptosis atlas. We discovered that TNBCs had heterogeneous phenotypes in ferroptosis-related metabolites and metabolic pathways. The luminal androgen receptor (LAR) subtype of TNBC was characterized by the upregulation of oxidized phosphatidylethanolamines and glutathione metabolism (especially GPX4), which allowed the utilization of GPX4 inhibitors to induce ferroptosis. Furthermore, we verified that GPX4 inhibition not only induced tumor ferroptosis but also enhanced antitumor immunity. The combination of GPX4 inhibitors and anti-PD1 possessed greater therapeutic efficacy than monotherapy. Clinically, higher GPX4 expression correlated with lower cytolytic scores and worse prognosis in immunotherapy cohorts. Collectively, this study demonstrated the ferroptosis landscape of TNBC and revealed an innovative immunotherapy combination strategy for refractory LAR tumors.
Collapse
Affiliation(s)
- Fan Yang
- Key Laboratory of Breast Cancer in Shanghai, Department of Breast Surgery, Fudan University Shanghai Cancer Center, Shanghai Medical College, Fudan University, Shanghai 200032, China; Department of Oncology, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Yi Xiao
- Key Laboratory of Breast Cancer in Shanghai, Department of Breast Surgery, Fudan University Shanghai Cancer Center, Shanghai Medical College, Fudan University, Shanghai 200032, China; Department of Oncology, Shanghai Medical College, Fudan University, Shanghai 200032, China.
| | - Jia-Han Ding
- Key Laboratory of Breast Cancer in Shanghai, Department of Breast Surgery, Fudan University Shanghai Cancer Center, Shanghai Medical College, Fudan University, Shanghai 200032, China; Department of Oncology, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Xi Jin
- Key Laboratory of Breast Cancer in Shanghai, Department of Breast Surgery, Fudan University Shanghai Cancer Center, Shanghai Medical College, Fudan University, Shanghai 200032, China; Department of Oncology, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Ding Ma
- Key Laboratory of Breast Cancer in Shanghai, Department of Breast Surgery, Fudan University Shanghai Cancer Center, Shanghai Medical College, Fudan University, Shanghai 200032, China; Department of Oncology, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Da-Qiang Li
- Key Laboratory of Breast Cancer in Shanghai, Department of Breast Surgery, Fudan University Shanghai Cancer Center, Shanghai Medical College, Fudan University, Shanghai 200032, China; Department of Oncology, Shanghai Medical College, Fudan University, Shanghai 200032, China; Shanghai Key Laboratory of Medical Epigenetics, International Co-Laboratory of Medical Epigenetics and Metabolism, Ministry of Science and Technology, Institutes of Biomedical Sciences, Fudan University, Shanghai 200032, China
| | - Jin-Xiu Shi
- Shanghai-MOST Key Laboratory of Health and Disease Genomics, Chinese National Human Genome Center at Shanghai (CHGC) and Shanghai Institute for Biomedical and Pharmaceutical Technologies (SIBPT), Shanghai 201203, China
| | - Wei Huang
- Shanghai-MOST Key Laboratory of Health and Disease Genomics, Chinese National Human Genome Center at Shanghai (CHGC) and Shanghai Institute for Biomedical and Pharmaceutical Technologies (SIBPT), Shanghai 201203, China
| | - Yi-Ping Wang
- Key Laboratory of Breast Cancer in Shanghai, Department of Breast Surgery, Fudan University Shanghai Cancer Center, Shanghai Medical College, Fudan University, Shanghai 200032, China; Department of Oncology, Shanghai Medical College, Fudan University, Shanghai 200032, China; Shanghai Key Laboratory of Medical Epigenetics, International Co-Laboratory of Medical Epigenetics and Metabolism, Ministry of Science and Technology, Institutes of Biomedical Sciences, Fudan University, Shanghai 200032, China; Shanghai Key Laboratory of Radiation Oncology, Fudan University Shanghai Cancer Center, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Yi-Zhou Jiang
- Key Laboratory of Breast Cancer in Shanghai, Department of Breast Surgery, Fudan University Shanghai Cancer Center, Shanghai Medical College, Fudan University, Shanghai 200032, China; Department of Oncology, Shanghai Medical College, Fudan University, Shanghai 200032, China.
| | - Zhi-Ming Shao
- Key Laboratory of Breast Cancer in Shanghai, Department of Breast Surgery, Fudan University Shanghai Cancer Center, Shanghai Medical College, Fudan University, Shanghai 200032, China; Department of Oncology, Shanghai Medical College, Fudan University, Shanghai 200032, China.
| |
Collapse
|
3
|
Guerriero G, Brundo MV, Labar S, Bianchi AR, Trocchia S, Rabbito D, Palumbo G, Abdel-Gawad FK, De Maio A. Frog (Pelophylax bergeri, Günther 1986) endocrine disruption assessment: characterization and role of skin poly(ADP-ribose) polymerases. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2018; 25:18303-18313. [PMID: 29081042 DOI: 10.1007/s11356-017-0395-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Accepted: 10/02/2017] [Indexed: 06/07/2023]
Abstract
Model of the our research was the adult male amphibian anura, Pelophylax bergeri, poikilotherm species not considered threatened by the IUCN, sampled in representative sites at different degree. In the first phase, a biochemical characterization of the ADP-ribosylation on the skin of barcoded amphibian anura collected from Matese Lake (clean reference site in CE, Italy) was carried out. Two PARP isoforms were evidence: the first of 66 kDa is localized into nucleus and activated by DNA damage; the second of 150 kDa is in cytoplasm, as demonstrated by biochemical and immunohistochemical analysis. Subsequently, the PARP activity, the quantitative expression of androgen receptor gene, and the levels of arsenic and chromium in skin and testis of frog and soil, water, and sediment collected from sites at different degrees of pollution were measured. A significant variation of PARP activity and androgen receptor expression levels was detected in both tissues of barcoded frogs from Sarno and Scafati, along Sarno River (SA, Italy), suggesting that a PARP activation is correlated to pollution and to steroid-regulated physiology disruption.
Collapse
Affiliation(s)
- Giulia Guerriero
- Dipartimento di Biologia, Università degli Studi di Napoli Federico II, Napoli, Italy.
- Interdepartmental Research Center for Environment (I.R.C.Env.), Università degli Studi di Napoli Federico II, Napoli, Italy.
| | - Maria Violetta Brundo
- Dipartimento di Scienze Biologiche, Geologiche ed Ambientali, Università di Catania, Catania, Italy
| | - Sofiane Labar
- Dipartimento di Biologia, Università degli Studi di Napoli Federico II, Napoli, Italy
- Department of Biology, Chadli bendjedid El Tarf University, El Tarf, Algeria
| | - Anna Rita Bianchi
- Dipartimento di Biologia, Università degli Studi di Napoli Federico II, Napoli, Italy
| | - Samantha Trocchia
- Dipartimento di Biologia, Università degli Studi di Napoli Federico II, Napoli, Italy
| | - Dea Rabbito
- Dipartimento di Biologia, Università degli Studi di Napoli Federico II, Napoli, Italy
| | - Giancarlo Palumbo
- Dipartimento di Scienze Chimiche, University of Naples Federico II, Napoli, Italy
| | - Fagr Kh Abdel-Gawad
- Center of Excellence for Advanced Science, Environmental Sciences Research Division, National Research Center, Giza, Egypt
| | - Anna De Maio
- Dipartimento di Biologia, Università degli Studi di Napoli Federico II, Napoli, Italy
| |
Collapse
|
4
|
Nilsson EM, Fainberg HP, Choong SS, Giles TC, Sells J, May S, Stansfield FJ, Allen WR, Emes RD, Mostyn A, Mongan NP, Yon L. Molecular characterization of adipose tissue in the African elephant (Loxodonta africana). PLoS One 2014; 9:e91717. [PMID: 24633017 PMCID: PMC3954733 DOI: 10.1371/journal.pone.0091717] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2013] [Accepted: 02/14/2014] [Indexed: 01/01/2023] Open
Abstract
Adipose tissue (AT) is a dynamic and flexible organ with regulatory roles in physiological functions including metabolism, reproduction and inflammation; secreted adipokines, including leptin, and fatty acids facilitate many of these roles. The African elephant (Loxodonta africana) is experiencing serious challenges to optimal reproduction in captivity. The physiological and molecular basis of this impaired fertility remains unknown. AT production of leptin is a crucial molecular link between nutritional status, adiposity and fertility in many species. We propose that leptin has a similar function in the African elephant. African elephant visceral and subcutaneous adipose tissue (AT) was obtained from both sexes and a range of ages including females with known pregnancy status. RNA was extracted and histological sections created and analyzed by microarray, PCR and immunohistochemistry respectively. Gas-chromatography was used to determine the fatty acid composition of AT. Microarray expression profiling was used to compare gene expression profiles of AT from pre-pubertal versus reproductively competent adult African elephants. This study demonstrates, for the first time, leptin mRNA and protein expression in African elephant AT. The derived protein sequence of the elephant leptin protein was exploited to determine its relationship within the class I helical cytokine superfamily, which indicates that elephant leptin is most closely related to the leptin orthologs of Oryctolagus cuniculus (European rabbit), Lepus oiostolus (woolly hare), and members of the Ochotonidae (Pika). Immunohistological analysis identified considerable leptin staining within the cytoplasm of adipocytes. Significant differences in fatty acid profiles between pregnant and non-pregnant animals were revealed, most notably a reduction in both linoleic and α linoleic acid in pregnant animals. This report forms the basis for future studies to address the effect of nutrient composition and body condition on reproduction in captive and wild elephants.
Collapse
Affiliation(s)
- Emeli M. Nilsson
- Faculty of Medicine and Health Sciences, School of Veterinary Medicine and Science, Sutton Bonington Campus, University of Nottingham, Sutton Bonington, United Kingdom
| | - Hernan P. Fainberg
- Faculty of Medicine and Health Sciences, School of Veterinary Medicine and Science, Sutton Bonington Campus, University of Nottingham, Sutton Bonington, United Kingdom
| | - Siew S. Choong
- Faculty of Medicine and Health Sciences, School of Veterinary Medicine and Science, Sutton Bonington Campus, University of Nottingham, Sutton Bonington, United Kingdom
| | - Thomas C. Giles
- Advanced Data Analysis Centre, University of Nottingham, Sutton Bonington, United Kingdom
| | - James Sells
- Faculty of Medicine and Health Sciences, School of Veterinary Medicine and Science, Sutton Bonington Campus, University of Nottingham, Sutton Bonington, United Kingdom
| | - Sean May
- The Nottingham Arabidopsis Stock Centre, Division of Plant Sciences, University of Nottingham, Sutton Bonington, United Kingdom
| | - Fiona J. Stansfield
- The Elephant Research and Conservation Unit, Savé Valley Conservancy, Harare, Zimbabwe
| | - William R. Allen
- The Paul Mellon Laboratory, “Brunswick,” Woodditton Road, Newmarket, Suffolk, United Kingdom
| | - Richard D. Emes
- Faculty of Medicine and Health Sciences, School of Veterinary Medicine and Science, Sutton Bonington Campus, University of Nottingham, Sutton Bonington, United Kingdom
- Advanced Data Analysis Centre, University of Nottingham, Sutton Bonington, United Kingdom
| | - Alison Mostyn
- Faculty of Medicine and Health Sciences, School of Veterinary Medicine and Science, Sutton Bonington Campus, University of Nottingham, Sutton Bonington, United Kingdom
| | - Nigel P. Mongan
- Faculty of Medicine and Health Sciences, School of Veterinary Medicine and Science, Sutton Bonington Campus, University of Nottingham, Sutton Bonington, United Kingdom
| | - Lisa Yon
- Faculty of Medicine and Health Sciences, School of Veterinary Medicine and Science, Sutton Bonington Campus, University of Nottingham, Sutton Bonington, United Kingdom
| |
Collapse
|
5
|
Loss of androgen receptor promotes adipogenesis but suppresses osteogenesis in bone marrow stromal cells. Stem Cell Res 2013; 11:938-50. [PMID: 23859805 DOI: 10.1016/j.scr.2013.06.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/11/2013] [Revised: 05/29/2013] [Accepted: 06/02/2013] [Indexed: 11/21/2022] Open
Abstract
Gender differences have been described in osteoporosis with females having a higher risk of osteoporosis than males. The differentiation of bone marrow stromal cells (BMSCs) into bone or fat is a critical step for osteoporosis. Here we demonstrated that loss of the androgen receptor (AR) in BMSCs suppressed osteogenesis but promoted adipogenesis. The mechanism dissection studies revealed that AR deficiency suppressed osteogenesis-related genes to inhibit osteoblast differentiation from BMSCs. Knockout of AR promoted adipogenesis of BMSCs via Akt activation through IGFBP3-mediated IGF signaling, and the 5' promoter assay and chromatin immunoprecipitation assays further proved that AR could modulate IGFBP3 expression at the transcriptional level. Finally, addition of IGF inhibitors successfully masked the AR deficiency-induced Akt activation, and inhibitions of Akt, IGF1, and IGF2 pathways reversed the AR depletion effects on the adipogenesis process. These results suggested that AR-mediated changes in IGFBP3 might modulate the IGF-Akt axis to regulate adipogenesis in BMSCs.
Collapse
|
6
|
Dihydrotestosterone regulating apolipoprotein M expression mediates via protein kinase C in HepG2 cells. Lipids Health Dis 2012; 11:168. [PMID: 23216709 PMCID: PMC3543304 DOI: 10.1186/1476-511x-11-168] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2012] [Accepted: 11/20/2012] [Indexed: 11/14/2022] Open
Abstract
Background Administration of androgens decreases plasma concentrations of high-density lipid cholesterol (HDL-C). However, the mechanisms by which androgens mediate lipid metabolism remain unknown. This present study used HepG2 cell cultures and ovariectomized C57BL/6 J mice to determine whether apolipoprotein M (ApoM), a constituent of HDL, was affected by dihydrotestosterone (DHT). Methods HepG2 cells were cultured in the presence of either DHT, agonist of protein kinase C (PKC), phorbol-12-myristate-13-acetate (PMA), blocker of androgen receptor flutamide together with different concentrations of DHT, or DHT together with staurosporine at different concentrations for 24 hrs. Ovariectomized C57BL/6 J mice were treated with DHT or vehicle for 7d or 14d and the levels of plasma ApoM and livers ApoM mRNA were measured. The mRNA levels of ApoM, ApoAI were determined by real-time RT-PCR. ApoM and ApoAI were determined by western blotting analysis. Results Addition of DHT to cell culture medium selectively down-regulated ApoM mRNA expression and ApoM secretion in a dose-dependent manner. At 10 nM DHT, the ApoM mRNA levels were about 20% lower than in untreated cells and about 40% lower at 1000 nM DHT than in the control cells. The secretion of ApoM into the medium was reduced to a similar extent. The inhibitory effect of DHT on ApoM secretion was not blocked by the classical androgen receptor blocker flutamide but by an antagonist of PKC, Staurosporine. Agonist of PKC, PMA, also reduced ApoM. At 0.5 μM PMA, the ApoM mRNA levels and the secretion of ApoM into the medium were about 30% lower than in the control cells. The mRNA expression levels and secretion of another HDL-associated apolipoprotein AI (ApoAI) were not affected by DHT. The levels of plasma ApoM and liver ApoM mRNA of DHT-treated C57BL/6 J mice were lower than those of vehicle-treated mice. Conclusions DHT directly and selectively down-regulated the level of ApoM mRNA and the secretion of ApoM by protein kinase C but independently of the classical androgen receptor.
Collapse
|
7
|
Miller CP, Shomali M, Lyttle CR, O’Dea LSL, Herendeen H, Gallacher K, Paquin D, Compton DR, Sahoo B, Kerrigan SA, Burge MS, Nickels M, Green JL, Katzenellenbogen JA, Tchesnokov A, Hattersley G. Design, Synthesis, and Preclinical Characterization of the Selective Androgen Receptor Modulator (SARM) RAD140. ACS Med Chem Lett 2011; 2:124-9. [PMID: 24900290 PMCID: PMC4018048 DOI: 10.1021/ml1002508] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2010] [Accepted: 11/15/2010] [Indexed: 01/03/2023] Open
Abstract
This report describes the discovery of RAD140, a potent, orally bioavailable, nonsteroidal selective androgen receptor modulator (SARM). The characterization of RAD140 in several preclinical models of anabolic androgen action is also described.
Collapse
Affiliation(s)
- Chris P. Miller
- Radius Health, Inc., 300 Technology Square, Cambridge, Massachusetts 02139, United States
| | - Maysoun Shomali
- Radius Health, Inc., 300 Technology Square, Cambridge, Massachusetts 02139, United States
| | - C. Richard Lyttle
- Radius Health, Inc., 300 Technology Square, Cambridge, Massachusetts 02139, United States
| | - Louis St. L. O’Dea
- Radius Health, Inc., 300 Technology Square, Cambridge, Massachusetts 02139, United States
| | - Hillary Herendeen
- Radius Health, Inc., 300 Technology Square, Cambridge, Massachusetts 02139, United States
| | - Kyla Gallacher
- Radius Health, Inc., 300 Technology Square, Cambridge, Massachusetts 02139, United States
| | - Dottie Paquin
- Radius Health, Inc., 300 Technology Square, Cambridge, Massachusetts 02139, United States
| | - Dennis R. Compton
- Obiter Research, 2809 Gemini Court, Champaign, Illinois 61822-9647, United States
| | - Bishwabhusan Sahoo
- Obiter Research, 2809 Gemini Court, Champaign, Illinois 61822-9647, United States
| | - Sean A. Kerrigan
- Obiter Research, 2809 Gemini Court, Champaign, Illinois 61822-9647, United States
| | - Matthew S. Burge
- Obiter Research, 2809 Gemini Court, Champaign, Illinois 61822-9647, United States
| | - Michael Nickels
- Obiter Research, 2809 Gemini Court, Champaign, Illinois 61822-9647, United States
| | - Jennifer L. Green
- Obiter Research, 2809 Gemini Court, Champaign, Illinois 61822-9647, United States
| | - John A. Katzenellenbogen
- Department of Chemistry, University of Illinois at Urbana−Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801, United States
| | - Alexei Tchesnokov
- Cambridge Major Laboratories, Inc., W130 N10497 Washington Drive, Germantown, Wisconsin 53022, United States
| | - Gary Hattersley
- Radius Health, Inc., 300 Technology Square, Cambridge, Massachusetts 02139, United States
| |
Collapse
|
8
|
Schmidt A, Kimmel DB, Bai C, Scafonas A, Rutledge S, Vogel RL, McElwee-Witmer S, Chen F, Nantermet PV, Kasparcova V, Leu CT, Zhang HZ, Duggan ME, Gentile MA, Hodor P, Pennypacker B, Masarachia P, Opas EE, Adamski SA, Cusick TE, Wang J, Mitchell HJ, Kim Y, Prueksaritanont T, Perkins JJ, Meissner RS, Hartman GD, Freedman LP, Harada SI, Ray WJ. Discovery of the selective androgen receptor modulator MK-0773 using a rational development strategy based on differential transcriptional requirements for androgenic anabolism versus reproductive physiology. J Biol Chem 2010; 285:17054-64. [PMID: 20356837 DOI: 10.1074/jbc.m109.099002] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Selective androgen receptor modulators (SARMs) are androgen receptor (AR) ligands that induce anabolism while having reduced effects in reproductive tissues. In various experimental contexts SARMs fully activate, partially activate, or even antagonize the AR, but how these complex activities translate into tissue selectivity is not known. Here, we probed receptor function using >1000 synthetic AR ligands. These compounds produced a spectrum of activities in each assay ranging from 0 to 100% of maximal response. By testing different classes of compounds in ovariectomized rats, we established that ligands that transactivated a model promoter 40-80% of an agonist, recruited the coactivator GRIP-1 <15%, and stabilized the N-/C-terminal interdomain interaction <7% induced bone formation with reduced effects in the uterus and in sebaceous glands. Using these criteria, multiple SARMs were synthesized including MK-0773, a 4-aza-steroid that exhibited tissue selectivity in humans. Thus, AR activated to moderate levels due to reduced cofactor recruitment, and N-/C-terminal interactions produce a fully anabolic response, whereas more complete receptor activation is required for reproductive effects. This bimodal activation provides a molecular basis for the development of SARMs.
Collapse
Affiliation(s)
- Azriel Schmidt
- Department of Molecular Endocrinology, Merck Research Laboratories, West Point, Pennsylvania 19486, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
9
|
Gupta V, Bhasin S, Guo W, Singh R, Miki R, Chauhan P, Choong K, Tchkonia T, Lebrasseur NK, Flanagan JN, Hamilton JA, Viereck JC, Narula NS, Kirkland JL, Jasuja R. Effects of dihydrotestosterone on differentiation and proliferation of human mesenchymal stem cells and preadipocytes. Mol Cell Endocrinol 2008; 296:32-40. [PMID: 18801408 PMCID: PMC2873614 DOI: 10.1016/j.mce.2008.08.019] [Citation(s) in RCA: 115] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/05/2008] [Revised: 07/29/2008] [Accepted: 08/10/2008] [Indexed: 10/21/2022]
Abstract
UNLABELLED The mechanisms by which androgens regulate fat mass are poorly understood. Although testosterone has been reported to increase lipolysis and inhibit lipid uptake, androgen effects on proliferation and differentiation of human mesenchymal stem cells (hMSCs) and preadipocytes have not been studied. Here, we investigated whether dihydrotestosterone (DHT) regulates proliferation, differentiation, or functional maturation of hMSCs and human preadipocytes from different fat depots. DHT (0-30 nM) dose-dependently inhibited lipid accumulation in adipocytes differentiated from hMSCs and downregulated expression of aP2, PPARgamma, leptin, and C/EBPalpha. Bicalutamide attenuated DHT's inhibitory effects on adipogenic differentiation of hMSCs. Adipocytes differentiated in presence of DHT accumulated smaller oil droplets suggesting reduced extent of maturation. DHT decreased the incorporation of labeled fatty acid into triglyceride, and downregulated acetyl CoA carboxylase and DGAT2 expression in adipocytes derived from hMSCs. DHT also inhibited lipid accumulation and downregulated aP2 and C/EBPalpha in human subcutaneous, mesenteric and omental preadipocytes. DHT stimulated forskolin-stimulated lipolysis in subcutaneous and mesenteric preadipocytes and inhibited incorporation of fatty acid into triglyceride in adipocytes differentiated from preadipocytes from all fat depots. CONCLUSIONS DHT inhibits adipogenic differentiation of hMSCs and human preadipocytes through an AR-mediated pathway, but it does not affect the proliferation of either hMSCs or preadipocytes. Androgen effects on fat mass represent the combined effect of decreased differentiation of fat cell precursors, increased lipolysis, and reduced lipid accumulation.
Collapse
Affiliation(s)
- Vandana Gupta
- Department of Medicine, Boston University, School of Medicine, Boston Medical Center, Boston, MA 02118, United States
| | - Shalender Bhasin
- Department of Medicine, Boston University, School of Medicine, Boston Medical Center, Boston, MA 02118, United States
| | - Wen Guo
- Department of Medicine, Boston University, School of Medicine, Boston Medical Center, Boston, MA 02118, United States
| | - Rajan Singh
- Charles R. Drew University, Los Angeles, CA 90059, United States
| | - Rika Miki
- Charles R. Drew University, Los Angeles, CA 90059, United States
| | - Pratibha Chauhan
- Department of Medicine, Boston University, School of Medicine, Boston Medical Center, Boston, MA 02118, United States
| | - Karen Choong
- Department of Medicine, Boston University, School of Medicine, Boston Medical Center, Boston, MA 02118, United States
| | - Tamara Tchkonia
- Department of Medicine, Boston University, School of Medicine, Boston Medical Center, Boston, MA 02118, United States
| | - Nathan K. Lebrasseur
- Department of Medicine, Boston University, School of Medicine, Boston Medical Center, Boston, MA 02118, United States
| | - John N. Flanagan
- Department of Medicine, Boston University, School of Medicine, Boston Medical Center, Boston, MA 02118, United States
| | - James A. Hamilton
- Department of Biophysics, Boston University, School of Medicine, Boston Medical Center, Boston, MA 02118, United States
| | - Jason C. Viereck
- Department of Biophysics, Boston University, School of Medicine, Boston Medical Center, Boston, MA 02118, United States
| | - Navjot S. Narula
- Department of Medicine, Boston University, School of Medicine, Boston Medical Center, Boston, MA 02118, United States
| | - James L. Kirkland
- Department of Medicine, Boston University, School of Medicine, Boston Medical Center, Boston, MA 02118, United States
| | - Ravi Jasuja
- Department of Medicine, Boston University, School of Medicine, Boston Medical Center, Boston, MA 02118, United States
- Charles R. Drew University, Los Angeles, CA 90059, United States
| |
Collapse
|
10
|
Shi L, Ko S, Kim S, Echchgadda I, Oh TS, Song CS, Chatterjee B. Loss of androgen receptor in aging and oxidative stress through Myb protooncoprotein-regulated reciprocal chromatin dynamics of p53 and poly(ADP-ribose) polymerase PARP-1. J Biol Chem 2008; 283:36474-85. [PMID: 18945670 DOI: 10.1074/jbc.m805980200] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Poly(ADP-ribosyl)ation of transcription factors and coregulators, mediated by the poly(ADP-ribose) polymerase PARP-1, has been emerging as an important epigenetic mechanism that controls transcriptional dynamics in response to diverse intra- and extracellular signals. PARP-1 activity is also implicated in the regulation of mammalian lifespan. Herein we show that transcriptional down-regulation of androgen receptor (AR) in the aging rat liver and in oxidatively stressed hepatoma cells involves exchange of a PARP-1-associated, p/CAF-containing coactivator assembly for a p53-interacting, Groucho/TLE1-, and mSin3A-included corepressor complex at an age- and oxidant-responsive DNA element (age-dependent factor (ADF) element) in the AR promoter. The coregulator switch is mediated by B-Myb and c-Myb, which bind to the ADF element and physically associate with PARP-1 and the tumor suppressor p53. Heterogeneous nuclear ribonucleoprotein K, residing at the ADF element in association with PARP-1, may serve a platform role in stabilizing the activating complex. PARP-1 coactivated B-Myb- and c-Myb-mediated transactivation of the AR promoter, and p53 antagonized the B-Myb/c-Myb-induced AR promoter activation. PARP-1, heterogeneous nuclear ribonucleoprotein K, B-Myb, and c-Myb each serves as a positive regulator of cellular AR content, whereas p53 negatively regulates AR expression. Our results identify a shared, PARP-1-regulated sensing mechanism that coordinates transcriptional repression of AR during aging and in response to oxidative stress. This study may provide insights as to how advancing age and intracellular redox balance might influence androgen-regulated physiology.
Collapse
Affiliation(s)
- Liheng Shi
- Department of Molecular Medicine/Institute of Biotechnology, The University of Texas Health Science Center, San Antonio, Texas 78245, USA
| | | | | | | | | | | | | |
Collapse
|