Journal of molecular endocrinology最新文献

{"title":"RISING STARS: Targeting G protein-coupled receptors to regulate energy homeostasis.","authors":"Aqfan Jamaluddin,&nbsp;Caroline M Gorvin","doi":"10.1530/JME-23-0014","DOIUrl":"10.1530/JME-23-0014","url":null,"abstract":"<p><p>G protein-coupled receptors (GPCRs) have a critical role in energy homeostasis, contributing to food intake, energy expenditure and glycaemic control. Dysregulation of energy expenditure can lead to metabolic syndrome (abdominal obesity, elevated plasma triglyceride, LDL cholesterol and glucose, and high blood pressure), which is associated with an increased risk of developing obesity, diabetes mellitus, non-alcoholic fatty liver disease and cardiovascular complications. As the prevalence of these chronic diseases continues to rise worldwide, there is an increased need to understand the molecular mechanisms by which energy expenditure is regulated to facilitate the development of effective therapeutic strategies to treat and prevent these conditions. In recent years, drugs targeting GPCRs have been the focus of efforts to improve treatments for type-2 diabetes and obesity, with GLP-1R agonists a particular success. In this review, we focus on nine GPCRs with roles in energy homeostasis that are current and emerging targets to treat obesity and diabetes. We discuss findings from pre-clinical models and clinical trials of drugs targeting these receptors and challenges that must be overcome before these drugs can be routinely used in clinics. We also describe new insights into how these receptors signal, including how accessory proteins, biased signalling, and complex spatial signalling could provide unique opportunities to develop more efficacious therapies with fewer side effects. Finally, we describe how combined therapies, in which multiple GPCRs are targeted, may improve clinical outcomes and reduce off-target effects.</p>","PeriodicalId":16570,"journal":{"name":"Journal of molecular endocrinology","volume":"70 4","pages":""},"PeriodicalIF":3.5,"publicationDate":"2023-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10160555/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9687287","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"PPP2R2A promotes testosterone secretion in Hu sheep Leydig cells via activation of the AKT/mTOR signaling pathway.","authors":"Xiaodan Li,&nbsp;Xiaolei Yao,&nbsp;Yongjin Bao,&nbsp;Kaiping Deng,&nbsp;Mingtian Deng,&nbsp;Fan Yang,&nbsp;Xuan Sun,&nbsp;Peihua You,&nbsp;Qingxian Cai,&nbsp;Feng Wang","doi":"10.1530/JME-22-0130","DOIUrl":"10.1530/JME-22-0130","url":null,"abstract":"<p><p>The serine-threonine protein phosphatase 2A (PP2A) is a heterotrimeric enzyme complex that plays a vital role in regulating male reproductive activities. However, as an essential member of the PP2A family, the physiological functions of PP2A regulatory subunit B55α (PPP2R2A) in testis remain inconclusive. Hu sheep are noted for their reproductive precocity and fertility, and are ideal models for the study of male reproductive physiology. Here, we analyzed the expression patterns of PPP2R2A in the male Hu sheep reproductive tract at different developmental stages and further investigated its role in testosterone secretion and its underlying mechanisms. In this study, we found that there were temporal and spatial differences in PPP2R2A protein expression in the testis and epididymis, especially the expression abundance in the testis at 8 months old (8M) was higher than that at 3 months old (3M). Interestingly, we observed that PPP2R2A interference reduced the testosterone levels in the cell culture medium, which is accompanied by a reduction in Leydig cell proliferation and an elevation in Leydig cell apoptosis. The level of reactive oxygen species in cells increased significantly, while the mitochondrial membrane potential (ΔΨm) decreased significantly after PPP2R2A deletion. Meanwhile, the mitochondrial mitotic protein DNM1L was significantly upregulated, while the mitochondrial fusion proteins MFN1/2 and OPA1 were significantly downregulated after PPP2R2A interference. Furthermore, PPP2R2A interference suppressed the AKT/mTOR signaling pathway. Taken together, our data indicated that PPP2R2A enhanced testosterone secretion, promoted cell proliferation, and inhibited cell apoptosis in vitro, all of which were associated with the AKT/mTOR signaling pathway.</p>","PeriodicalId":16570,"journal":{"name":"Journal of molecular endocrinology","volume":"70 4","pages":""},"PeriodicalIF":3.5,"publicationDate":"2023-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10043368","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"CTCF variant begets to short stature by down-regulation of IGF1.","authors":"Hong Chen,&nbsp;Weiyu Li,&nbsp;Suping Zhang,&nbsp;Yunteng Sun,&nbsp;Yiping Shen,&nbsp;Ruimin Chen","doi":"10.1530/JME-22-0193","DOIUrl":"10.1530/JME-22-0193","url":null,"abstract":"<p><p>Pathogenic variants in the transcription factor CCCTC-binding factor (CTCF) are associated with mental retardation, autosomal dominant 21 (MRD21, MIM#615502). Current studies supported the strong relationship between CTCF variants and growth, yet the mechanism of CTCF mutation leading to short stature is not known. Clinical information, treatment regimens, and follow-up outcomes of a patient with MRD21 were collected. The possible pathogenic mechanisms of CTCF variants leading to short stature were investigated using immortalized lymphocyte cell lines (LCLs), HEK-293T, and immortalized normal human liver cell lines (LO2). This patient received long-term treatment with recombinant human growth hormone (rhGH) which resulted in an increased height of 1.0 SDS. She had low serum insulin-like growth factor 1 (IGF1) before the treatment and the IGF1 level was not significantly increased during the treatment (-1.38 ± 0.61 SDS). The finding suggested that the CTCF R567W variant could have impaired IGF1 production pathway. We further demonstrated that the mutant CTCF had a reduced ability to bind to the promoter region of IGF1, consequently significantly reducing the transcriptional activation and expression of IGF1. Our novel results demonstrated a direct positive regulation of CTCF on the transcription of the IGF1 promoter. The impaired IGF1 expression due to CTCF mutation may explain the substandard effect of rhGH treatment on MRD21 patients. This study provided novel insights into the molecular basis of CTCF-associated disorder.</p>","PeriodicalId":16570,"journal":{"name":"Journal of molecular endocrinology","volume":"70 4","pages":""},"PeriodicalIF":3.5,"publicationDate":"2023-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10160550/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10043356","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cryo-electron microscopy structures of human thyroid peroxidase (TPO) in complex with TPO antibodies.","authors":"Stuart Baker,&nbsp;Ricardo Núñez Miguel,&nbsp;Daniel Thomas,&nbsp;Michael Powell,&nbsp;Jadwiga Furmaniak,&nbsp;Bernard Rees Smith","doi":"10.1530/JME-22-0149","DOIUrl":"https://doi.org/10.1530/JME-22-0149","url":null,"abstract":"Determination of the structure of the extracellular domain of human thyroid peroxidase (hTPO) by cryo-electron microscopy (cryo-EM) is described. TPO, purified to homogeneity was complexed with the hTPO monoclonal autoantibody 2G4 Fab and also with a mouse monoclonal TPO antibody 4F5 Fab (which competes with autoantibody binding to TPO). Both complexes were analysed by cryo-EM. The two structures (global resolution 3.92 and 3.4 Å for the 2G4 complex and 4F5 complex, respectively) show TPO as a monomer with four domains; the N-terminal domain, the peroxidase domain (POD), the complement control protein (CCP)-like domain and the epidermal growth factor-like domain which are all visible in the structures. The relative positions of the domains are fixed with a disulphide bond between cysteine residues Cys146 in the POD and Cys756 in the CCP domain preventing significant flexibility of the molecule. The entrance to the enzyme active site, the haem group and the calcium binding site are clearly visible on the opposite side of the TPO molecule from the 2G4 and 4F5 binding sites. Extensive interactions are seen between TPO and the two antibodies which both bind to distinct epitopes on the POD domain, including some residues in the immunodominant region B mainly via different residues. However, the epitopes of the two antibodies contain three shared TPO residues. This is the first high-resolution structure of TPO to be reported and it should help guide the development of new inhibitors of TPO enzyme activity for therapeutic applications.","PeriodicalId":16570,"journal":{"name":"Journal of molecular endocrinology","volume":"70 3","pages":""},"PeriodicalIF":3.5,"publicationDate":"2023-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9986399/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10855512","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Phospholipase D mediates very low-density lipoprotein-induced aldosterone production, in part, via lipin-1.","authors":"Shinjini C Spaulding,&nbsp;Vivek Choudhary,&nbsp;Wendy B Bollag","doi":"10.1530/JME-22-0196","DOIUrl":"10.1530/JME-22-0196","url":null,"abstract":"<p><p>Aldosterone is considered to be a link between hypertension and obesity; obese individuals have high serum levels of very low-density lipoprotein (VLDL). VLDL has been shown to induce aldosterone production in multiple adrenal zona glomerulosa models, mediated in part by phospholipase D (PLD). PLD is an enzyme that hydrolyzes phosphatidylcholine to produce phosphatidic acid (PA), a lipid second messenger that can also be dephosphorylated by lipin to yield diacylglycerol (DAG), yet another lipid signal. However, it is unclear which of the two lipid second messengers, PA or DAG, underlies PLD's mediation of aldosterone production. We hypothesized that the key signal produced by PLD (indirectly) is DAG such that PLD mediates VLDL-induced aldosterone production via lipin-mediated metabolism of PA to DAG. To assess the role of lipin in VLDL-induced aldosterone production, lipin-1 was overexpressed (using an adenovirus) or inhibited (using propranolol) in HAC15 cells followed by treatment with or without VLDL. Lipin-1 overexpression enhanced the VLDL-stimulated increase in CYP11B2 expression (by 75%), and lipin-1 inhibition decreased the VLDL-stimulated increase in CYP11B2 expression (by 66%). Similarly, the VLDL-stimulated increase in aldosterone production was enhanced by lipin-1 overexpression (182%) and was decreased by lipin inhibition (80%). Our results are suggestive of DAG being the key lipid signal since manipulating lipin-1 levels/activity affects VLDL-stimulated steroidogenic gene expression and ultimately, aldosterone production. Our study warrants further investigation into VLDL-stimulated steroidogenic signaling pathways which may lead to the identification of novel therapeutic targets, such as lipin-1 and its downstream pathways, to potentially treat obesity-associated hypertension.</p>","PeriodicalId":16570,"journal":{"name":"Journal of molecular endocrinology","volume":"70 4","pages":""},"PeriodicalIF":3.5,"publicationDate":"2023-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9607003","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cotadutide effect in liver and adipose tissue in obese mice.","authors":"Ilitch Aquino Marcondes-de-Castro,&nbsp;Thamiris Ferreira Oliveira,&nbsp;Renata Spezani,&nbsp;Thatiany Souza Marinho,&nbsp;Luiz Macedo Cardoso,&nbsp;Marcia Barbosa Aguila,&nbsp;Carlos Alberto Mandarim-de-Lacerda","doi":"10.1530/JME-22-0168","DOIUrl":"10.1530/JME-22-0168","url":null,"abstract":"<p><p>Obesity, adipose tissue inflammation, and nonalcoholic fatty liver disease (NAFLD) are associated with insulin resistance and type 2 diabetes (T2D). Cotadutide is a dual agonist GLP-1/glucagon, currently in a preclinical study phase 2 that presents an anti-obesity effect. Diet-induced obese (DIO) C57BL/6 mice were treated for 4 weeks with cotadutide (30 nm/kg once a day at 14:00 h). The study focused on epididymal white adipose tissue (eWAT), liver (NAFLD), inflammation, lipid metabolism, AMP-activated protein kinase (AMPK)/mechanistic target of rapamycin (mTOR) pathways, and the endoplasmic reticulum (ER) stress. As a result, cotadutide controlled weight gain, glucose intolerance, and insulin resistance and showed beneficial effects on plasma markers in DIO mice (triacylglycerol, total cholesterol, alanine aminotransferase, and aspartate aminotransferase, leptin, adiponectin, monocyte chemoattractant protein-1, resistin, interleukin-6, tumor necrosis factor-alpha). Also, cotadutide lessened liver fat accumulation, eWAT proinflammatory markers, and ER stress. In addition, cotadutide improved lipid metabolism genes in eWAT, fatty acid synthase, peroxisome proliferator-activated receptor gamma and mitigates adipocyte hypertrophy and apoptosis. Furthermore, the effects of cotadutide were related to liver AMPK/mTOR pathway and ER stress. In conclusion, cotadutide induces weight loss and treats glucose intolerance and insulin resistance in DIO mice. In addition, cotadutide shows beneficial effects on liver lipid metabolism, mitigating steatosis, inflammation, and ER stress. Besides, in adipocytes, cotadutide decreases hypertrophy and reduces apoptosis. These actions rescuing the AMPK and mTOR pathway, improving lipid metabolism, and lessening NAFLD, inflammation, and ER stress in both eWAT and liver of DIO mice indicate cotadutide as a potentially new pharmacological treatment for T2D and associated obesity.</p>","PeriodicalId":16570,"journal":{"name":"Journal of molecular endocrinology","volume":"70 3","pages":""},"PeriodicalIF":3.5,"publicationDate":"2023-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9114070","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Knockout of murine Lyplal1 confers sex-specific protection against diet-induced obesity.","authors":"Rishel B Vohnoutka, Annapurna Kuppa, Yash Hegde, Yue Chen, Asmita Pant, Maurice E Tohme, Eun-Young Karen Choi, Sean M McCarty, Devika P Bagchi, Xiaomeng Du, Yanhua Chen, Vincent L Chen, Hiroyuki Mori, Lawrence F Bielak, Lillias H Maguire, Samuel K Handelman, Jonathan Z Sexton, Thomas L Saunders, Brian D Halligan, Elizabeth K Speliotes","doi":"10.1530/JME-22-0131","DOIUrl":"10.1530/JME-22-0131","url":null,"abstract":"<p><p>Human genome-wide association studies found single-nucleotide polymorphisms (SNPs) near LYPLAL1 (Lysophospholipase-like protein 1) that have sex-specific effects on fat distribution and metabolic traits. To determine whether altering LYPLAL1 affects obesity and metabolic disease, we created and characterized a mouse knockout (KO) of Lyplal1. We fed the experimental group of mice a high-fat, high-sucrose (HFHS) diet for 23 weeks, and the controls were fed regular chow diet. Here, we show that CRISPR-Cas9 whole-body Lyplal1 KO mice fed an HFHS diet showed sex-specific differences in weight gain and fat accumulation as compared to chow diet. Female, not male, KO mice weighed less than WT mice, had reduced body fat percentage, had white fat mass, and had adipocyte diameter not accounted for by changes in the metabolic rate. Female, but not male, KO mice had increased serum triglycerides, decreased aspartate, and decreased alanine aminotransferase. Lyplal1 KO mice of both sexes have reduced liver triglycerides and steatosis. These diet-specific effects resemble the effects of SNPs near LYPLAL1 in humans, suggesting that LYPLAL1 has an evolutionary conserved sex-specific effect on adiposity. This murine model can be used to study this novel gene-by-sex-by-diet interaction to elucidate the metabolic effects of LYPLAL1 on human obesity.</p>","PeriodicalId":16570,"journal":{"name":"Journal of molecular endocrinology","volume":"70 3","pages":""},"PeriodicalIF":3.6,"publicationDate":"2023-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10947332/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9120134","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dysregulation of endoplasmic reticulum stress response in skin wounds in a streptozotocin-induced diabetes mouse model.","authors":"Ermelindo C Leal,&nbsp;Tatiana Emanuelli,&nbsp;Diana Santos,&nbsp;João Moura,&nbsp;Ana Catarina Rg Fonseca,&nbsp;Ana Burgeiro,&nbsp;Eugenia Carvalho","doi":"10.1530/JME-22-0122","DOIUrl":"10.1530/JME-22-0122","url":null,"abstract":"<p><p>Dysfunction in key cellular organelles has been linked to diabetic complications. This study intended to investigate the alterations in the unfolded protein response (UPR), autophagy, and mitochondrial function, which are part of the endoplasmic reticulum (ER) stress response, in wound healing (WH) under diabetes conditions. WH mouse models were used to evaluate the UPR, autophagy, mitochondrial fusion, fission, and biogenesis as well as mitophagy in the skin of control and diabetic mice at baseline and 10 days after wounding. The autophagic flux in response to high-glucose conditions was also evaluated in keratinocyte and fibroblast cell cultures. WH was impaired in the diabetic mouse model, and we found that the UPR and autophagy pathways were activated in skin wounds of control mice and in the non-wounded skin of diabetic mice. Moreover, high-glucose conditions induced autophagy in the keratinocyte and fibroblast cell cultures. However, mitophagy did not change in the skin of diabetic mice or the wounded skin. In addition, mitochondrial fusion was activated in control but not in the skin wounds of diabetic mice, while mitochondrial biogenesis is downregulated in the skin of diabetic mice. In conclusion, the activation of the UPR, autophagy, and mitochondrial remodeling are crucial for a proper WH. These results suggest that the increase in ER stress and autophagy in the skin of diabetic mice at baseline significantly escalated to pathological levels after wounding, contributing to impaired WH in diabetes.</p>","PeriodicalId":16570,"journal":{"name":"Journal of molecular endocrinology","volume":"70 3","pages":""},"PeriodicalIF":3.5,"publicationDate":"2023-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9118971","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"RISING STARS: Hormonal regulation of the breast cancer microenvironment.","authors":"Sarah Theresa Boyle","doi":"10.1530/JME-22-0174","DOIUrl":"10.1530/JME-22-0174","url":null,"abstract":"<p><p>The tumor microenvironment is a dynamic ecosystem of stromal and immune cells that, under the influence of cancer cells, govern biochemical signaling, mechanical signaling via production and remodeling of the extracellular matrix (ECM), formation of vascular networks, and ultimately promotion of tumor growth. In breast cancer, hormone receptor-mediated signaling is a key coordinator of cancer cell proliferation and invasiveness not only through cell-autonomous means but also via cancer cell-stroma cross-talk. In the absence of hormone receptors, a different microenvironment landscape emerges, which comes with its own challenges for therapy. This review summarizes the current knowledge regarding the associations of hormone receptor profiles with composition of the microenvironment, how hormones directly influence stromal cells, immune cells and cells associated with the vasculature, and the paracrine mechanisms that lead to the formation of a tumor-promoting ECM.</p>","PeriodicalId":16570,"journal":{"name":"Journal of molecular endocrinology","volume":"70 3","pages":""},"PeriodicalIF":3.5,"publicationDate":"2023-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10821715","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Finnish-specific AKT2 gene variant leads to impaired insulin signalling in myotubes.","authors":"Selina Mäkinen,&nbsp;Neeta Datta,&nbsp;Savithri Rangarajan,&nbsp;Yen Nguyen,&nbsp;Vesa Olkkonen,&nbsp;Aino Latva-Rasku,&nbsp;Pirjo Nuutila,&nbsp;Markku Laakso,&nbsp;Heikki A Koistinen","doi":"10.1530/JME-21-0285","DOIUrl":"https://doi.org/10.1530/JME-21-0285","url":null,"abstract":"<p><p>Finnish-specific gene variant p.P50T/AKT2 (minor allele frequency (MAF) = 1.1%) is associated with insulin resistance and increased predisposition to type 2 diabetes. Here, we have investigated in vitro the impact of the gene variant on glucose metabolism and intracellular signalling in human primary skeletal muscle cells, which were established from 14 male p.P50T/AKT2 variant carriers and 14 controls. Insulin-stimulated glucose uptake and glucose incorporation into glycogen were detected with 2-[1,2-3H]-deoxy-D-glucose and D-[14C]-glucose, respectively, and the rate of glycolysis was measured with a Seahorse XFe96 analyzer. Insulin signalling was investigated with Western blotting. The binding of variant and control AKT2-PH domains to phosphatidylinositol (3,4,5)-trisphosphate (PI(3,4,5)P3) was assayed using PIP StripsTM Membranes. Protein tyrosine kinase and serine-threonine kinase assays were performed using the PamGene® kinome profiling system. Insulin-stimulated glucose uptake and glycogen synthesis in myotubes in vitro were not significantly affected by the genotype. However, the insulin-stimulated glycolytic rate was impaired in variant myotubes. Western blot analysis showed that insulin-stimulated phosphorylation of AKT-Thr308, AS160-Thr642 and GSK3β-Ser9 was reduced in variant myotubes compared to controls. The binding of variant AKT2-PH domain to PI(3,4,5)P3 was reduced as compared to the control protein. PamGene® kinome profiling revealed multiple differentially phosphorylated kinase substrates, e.g. calmodulin, between the genotypes. Further in silico upstream kinase analysis predicted a large-scale impairment in activities of kinases participating, for example, in intracellular signal transduction, protein translation and cell cycle events. In conclusion, myotubes from p.P50T/AKT2 variant carriers show multiple signalling alterations which may contribute to predisposition to insulin resistance and T2D in the carriers of this signalling variant.</p>","PeriodicalId":16570,"journal":{"name":"Journal of molecular endocrinology","volume":"70 2","pages":""},"PeriodicalIF":3.5,"publicationDate":"2023-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9874976/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10808105","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}