Journal of Endocrinology最新文献

Diabetic osteoporosis is a metabolic disease that seriously endangers human health and Previous studies have found that denosumab and metformin have certain effects on bone metabolism and glucose metabolism, respectively. However, there is still a lack of relevant research on the effect of the combined use of two drugs. In this study, we sought to analyze the therapeutic effect of these two drugs combined on the glycemic and bone metabolic parameters in the treatment of type 2 diabetes with postmenopausal osteoporosis. A prospective cohort study was designed to include 537 cases of patients with type 2 diabetes with postmenopausal osteoporosis. Patients were treated with placebo alone (placebo, n=135), metformin alone (MET, n=132), denosumab alone (DEN, n=136), and the combination group (n=134) for 30 months. Baseline data at 10 months, 20 months, and 30 months, Dual Energy X-ray Absorptiometry (DEXA), and pQCT were used to identify spine and tibia bone microstructures, respectively. The combination therapy group demonstrated significantly greater improvements in bone mineral density (tibia, radius, spine, and whole body) and bone microstructure (tibia and radius) compared to MET or DEN monotherapy (P<0.05). Bone absorption markers such as CTX and ALP were decreased, the level of bone formation markers was further increased, and the progression of glucose metabolism was improved significantly (P<0.05) compared to DEN alone or using MET alone. Denosumab monotherapy (DEN) ameliorated bone loss while exerting modest effects on glucose metabolism progression. In contrast, metformin monotherapy (MET) significantly improved glycemic control but demonstrated limited efficacy against bone loss. Crucially, the metformin-denosumab combination synergistically mitigated bone loss in diabetic postmenopausal osteoporosis patients.

The expression of vaspin and GRP78 has been shown in the testis and ovary. The postnatal testis undergoes several changes in the expression of different proteins. The expression of vaspin and GRP78 has not been shown in the postnatal testis. It has also been shown that modulation of adipokine function could affect testicular germ cell proliferation and apoptosis. Whether vaspin regulates testicular proliferation and apoptosis in the early pubertal stage is still unknown. The aim of this study was to determine the expression of vaspin/GRP78 in postnatal testes of mice. Next, we investigated the effects of vaspin on cell proliferation and cell death (apoptosis, ferroptosis, and autophagy) in the pubertal testis. Immunohistochemistry and western blot analyses revealed that vaspin and GRP78 exhibit dynamic expression levels through developmental stages. In the testis, both proteins showed mild to moderate immunostaining in Leydig cells at early stages (PND7 and 14), with increasing intensity at PND21 and 42 in Leydig cells and spermatocytes, and round and elongated spermatids. The expression of vaspin and GRP78 was significantly down-regulated at postnatal day 21 (PND21). Moreover, exogenous vaspin treatment (PND21 to PND35) suppressed germ cell proliferation (BrdU labelling, PCNA, and GCNA) and apoptosis (decreased expression of active caspase-3 and TNFα) in the testis. The marker of autophagy, LAMP2, was elevated by vaspin treatment. Furthermore, vaspin treatment showed both stimulatory and inhibitory effects on markers of ferroptosis. In conclusion, vaspin/GRP78 could be a new regulator of cell proliferation and cell death in pubertal mouse testes.

Cardiovascular disease (CVD) is the leading cause of death among individuals with type II diabetes (T2D), affecting approximately 30 million people in the United States. During insulin resistance, the heart undergoes a metabolic shift, leading to increased reactive oxygen species generation, lipotoxicity, and mitochondrial dysfunction, ultimately contributing to cardiovascular dysfunction. The effects of thyroid hormones (THs) on redox biology and oxidative stress remain inconclusive, necessitating further investigation. In this study, insulin-resistant Otsuka Long Evans Tokushima Fatty (OLETF) rats were used to assess the impact of exogenous thyroxine (exoT4) on NADPH oxidases (NOX) and antioxidant defenses in the heart. Rats were assigned to four groups: i) lean control, Long Evans Tokushima Otsuka (LETO; n = 6), ii) LETO + T4 (8 μg/100 g BM/day for 5 weeks; n = 7), iii) untreated OLETF (n = 6), and iv) OLETF + T4 (n = 7). NOX4 mRNA expression was two-fold greater in OLETF rats compared to LETO. T4 treatment increased NOX4 protein abundance by 56% in OLETF. In addition, T4 normalized lipid peroxidation (4-hydroxynonenal) and tumor necrosis factor-α (TNF-α) levels while increasing nuclear factor erythroid 2-related factor 2 (Nrf2) mRNA expression by 158% compared to LETO and enhancing nuclear Nrf2 protein expression by 45% compared to untreated OLETF. Thioredoxin (TRX) expression, suppressed in OLETF, was increased by 88% following T4 treatment. ExoT4 increased mitofusin 2 (Mfn2) protein abundance in OLETF by 49% compared to LETO. These findings suggest that TH treatment may have cardioprotective effects mediated by Nrf2 in the heart during metabolic syndrome (MetS).

Osteoporosis (OP) is a systemic osteopathy characterized by a decrease in bone density and mass. Human bone mesenchymal stem cells (hBMSCs) exhibit multidirectional differentiation potential and play a critical role in bone metabolism. Herein, we investigated the diagnostic potential of miR-127-3p in OP and elucidated its regulatory role in hBMSCs, thereby providing novel insights into the diagnosis and progression prediction of OP. The relative expression of miR-127-3p was measured via RT-qPCR analysis. ROC curve and logistic analysis were applied to identify the diagnostic value of miR-127-3p for OP. The CCK8 assay and flow cytometry were used to assess cell viability and apoptosis. A luciferase reporter assay was performed to assess the interaction between VAMP2 and miR-127-3p. The bone differentiation markers RUNX2, OCN, and OPN were assayed using RT-qPCR and western blotting. We observed that the expression of miR-127-3p was reduced in patients with OP, allowing it to effectively distinguish these patients from healthy individuals. Transfection with miR-127-3p mimic inhibited hBMSC apoptosis, increased cell viability, and increased RUNX2, OCN, and OPN levels. Furthermore, miR-127-3p regulated hBMSCs via targeting VAMP2. Overexpression of VAMP2 reversed the effects of miR-127-3p on apoptosis, cell viability, and bone differentiation. In conclusion, these findings suggest that miR-127-3p may be a potential diagnostic tool for OP. In addition, miR-127-3p promotes hBMSC viability and differentiation through downregulating VAMP2; this decreases OP progression. Our findings will inform new ideas for the diagnosis and developmental prediction of OP.

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Abstract: Tributyltin (TBT) is a toxic compound used in antifouling paints and known for its endocrine-disrupting properties, including female reproductive dysfunction. We hypothesized that TBT exposure during gestation and lactation induces long-term reproductive alterations in female offspring. Pregnant Wistar rats were orally exposed from gestational day 7 to the end of lactation to 0.01% ethanol (control), TBT 100 ng/kg, or TBT 1000 ng/kg body weight. Female offspring were evaluated at postnatal days (PND) 21, 45, and 180 for biometric, hormonal, and ovarian parameters. Birth weight was reduced in the TBT100ng group, and body weight was reduced by PND180 in the TBT1000ng group. At PND45, testosterone increased in both TBT groups, while FSH decreased in the TBT100ng group. Estrous cyclicity irregularities, such as a prolonged metestrus-diestrus phase, were noted in the TBT1000ng group. Ovarian analysis showed increased cystic and atretic follicles at PND21 and PND45. Reduction in primordial follicles (TBT100ng) and corpora lutea (both TBT groups) was observed at PND180, along with ovarian fibrosis. TBT exposure led to age- and dose-dependent disruptions in ovarian follicle dynamics: initial increases in healthy follicles at PND21, followed by elevated unhealthy follicles and reduced healthy ones at later stages. At PND21, both TBT doses increased ERα expression, while TBT100ng increased AR expression. These changes were accompanied by a persistent increase in ovarian mast cells and elevated IL-6 protein expression, particularly at PND21 and PND180. Thus, maternal TBT exposure disrupts ovarian development and function, potentially increasing susceptibility to abnormal conditions such as polycystic ovary syndrome and primary ovarian insufficiency later in life.

Bariatric surgery (BS) is the most effective treatment for obesity and its related comorbidities, resulting in significant adipose tissue (AT) loss and functional recovery. However, the molecular mechanisms in the AT that drive these health benefits remain poorly understood, and predictive factors for adequate weight loss are currently needed. This study aimed to identify the proteomic signature of subcutaneous AT (SAT) linked to BS-induced weight loss and metabolic improvement, and to determine potential predictors of individual response. Sequential window acquisition of all theoretical mass spectra (SWATH-MS) proteomics was performed on paired abdominal SAT samples from individuals with obesity before and after BS. Bioinformatic and correlation analyses were conducted between proteomic data and changes in anthropometric and clinical parameters. In addition, the effect of sera from BS participants on subcutaneous adipocytes was assessed in vitro. The SAT response to BS was characterised by an up-regulation of mitochondrial metabolism and a down-regulation of inflammation, which correlated with different anthropometric and circulating markers. Notably, obesity duration was associated with BS-induced weight loss. Individuals with short-standing obesity (SSO) exhibited greater proteomic remodelling, weight reduction, and clinical improvement post-BS than those with long-standing obesity (LSO). Furthermore, a regulatory axis involving miR-223-3p, glucose metabolism, and cytoskeleton reorganisation in adipocytes might be connected to the positive effects of BS in LSO. Overall, our results indicate that obesity duration is related to BS-induced weight loss through SAT proteomic remodelling. Addressing this relationship could help develop new strategies to enhance weight management and metabolic health in people living with obesity.

Over the years, environmental exposure to pesticides has significantly increased. Several new pesticides are being developed and approved for use, although their full impact on health and the environment remains unclear. Pesticides interfere with the endocrine system by acting on hormonal pathways, including hormone-receptor interactions and hormonal metabolism. Concomitant with the increasing use of endocrine-disrupting chemical molecules, reduced fertility and reproductive alterations in men and women have attracted increasing attention in recent years. Given the potential of pesticides to impact the reproductive system significantly, we conducted a narrative review of relevant animal studies, including those conducted on humans, and in vitro models exploring changes in the male and female reproductive systems associated with exposure to various pesticide classes, such as organochlorines, organophosphates, pyrethroids, carbamates, and neonicotinoids. Key dysfunctions reported primarily in different experimental models include alterations in the hypothalamic-pituitary-gonadal axis, morphological changes in the ovaries and testes, increased numbers of atretic follicles, and reduced sperm motility. Although research in this area has increased, important gaps remain, including inconsistencies in findings, lack of long-term human exposure studies, and limited understanding of the synergistic effects of pesticide formulations. It is crucial to emphasize the impact of pesticide exposure on fertility and encourage further research to elucidate the pathophysiological, morphological, and molecular mechanisms involved, as well as the effects of exposure to mixtures of these pesticides, mimicking the human exposome.

Endocrine disruptors (EDs) are exogenous substances that interfere with the endocrine system, leading to adverse health outcomes. These substances, prevalent in industrial pollutants, pesticides, plastics, and personal care products, significantly impact hormonal regulation and disrupt various physiological processes. This review explores the sources and health impacts of EDs, focusing on their interference with hormonal axes, fetal development, and adipose tissue function. It highlights underlying mechanisms such as epigenetic modifications and discusses strategies to reduce ED exposure. Recent research reveals that EDs affect estrogen, androgen, and thyroid hormone signaling, contributing to developmental, reproductive, and metabolic disorders. Their interference with hormonal regulation is linked to abnormalities during fetal development and obesity through altered adipogenesis-related gene expression. Mechanisms such as DNA methylation, hypoxia-inducible factor signaling, and histone modifications play pivotal roles in ED-induced disruptions. Addressing ED exposure requires a multifaceted approach, incorporating lifestyle changes and public health initiatives to mitigate risks. Continued research is essential to better understand their effects and develop effective strategies for reducing their impact.

Hyperglycemia is the predominant endocrine and metabolic disorder, resulting in infertility in males. Adropin, a hepatokine, is a well-known insulin sensitizer that regulates glucose and lipid homeostasis. Our recent reports demonstrated the vital role of adropin in the regulation of testicular activity, but its role in testicular function during pathological conditions such as hyperglycemia has not yet been studied. Therefore, this study aimed to explore the effect of adropin treatment on reproductive and metabolic dysfunctions in hyperglycemic mice. Hyperglycemia was induced by streptozotocin (55 mg/kg body weight; i.p.) treatment followed by treatment with either adropin (450 nmol/kg body weight; i.p.) or metformin (500 mg/kg body weight; orally) for a period of 15 days. Treatment of hyperglycemic mice enhanced insulin sensitivity by increasing insulin receptor expression in the testis and decreasing HOMA-IR and circulating glucose level. Adropin treatment of hyperglycemic mice increased the production of testicular testosterone by promoting the expression of steroidogenic proteins. Moreover, adropin treatment also enhanced the proliferation and survival of testicular germ cells by increasing PCNA expression and decreasing BAX/Bcl2 ratio and TUNEL-positive cells in the testis of hyperglycemic mice. Flow cytometric analysis revealed an increased number of advanced germ cells in adropin-treated hyperglycemic mice. Notably, adropin treatment was more effective than metformin in restoring reproductive functions in hyperglycemic mice, as evidenced by the reestablishment of the testicular histoarchitecture and increased synthesis of testosterone in the testes. These findings suggest that adropin may serve as a viable therapeutic alternative to mitigate hyperglycemia-associated testicular dysfunction.

Statins are the most commonly used cholesterol-lowering medications, with proven efficacy in reducing cardiovascular disease in humans; however, statins are associated with a higher risk of new-onset type 2 diabetes (T2D). Mechanisms contributing to statin-induced diabetes are not well understood and may include effects on body composition, tissue insulin sensitivity, and/or pancreatic β-cell function. Given the essential role of the β-cell in maintaining normoglycemia, this review focuses on how statins may lead to the demise of the β-cell. We revisit what is known about the impact of statins on inhibition of the mevalonate pathway, including blockade of the synthesis of cholesterol and non-cholesterol products. We discuss aberrant expression of key β-cell genes and proteins, as well as dysregulation of β-cell components that facilitate normal insulin secretion, e.g., mitochondria and calcium channels. Importantly, we highlight areas that are understudied, including how statins alter cholesterol transport and metabolism in the β-cell, and the role of sex/gender in statin-induced β-cell dysfunction. As the number of statin users increases, there is an urgent need to address these gaps in our knowledge in order to shed light on strategies that limit statin-induced T2D.