Deficiency of the mitochondrial ribosomal subunit, MRPL50, causes autosomal recessive syndromic premature ovarian insufficiency.

Premature ovarian insufficiency (POI) is a common cause of infertility in women, characterised by amenorrhea and elevated FSH under the age of 40 years. In some cases, POI is syndromic in association with other features such as sensorineural hearing loss in Perrault syndrome. POI is a heterogeneous disease with over 80 causative genes known so far; however, these explain only a minority of cases. Using whole-exome sequencing (WES), we identified a MRPL50 homozygous missense variant (c.335T > A; p.Val112Asp) shared by twin sisters presenting with POI, bilateral high-frequency sensorineural hearing loss, kidney and heart dysfunction. MRPL50 encodes a component of the large subunit of the mitochondrial ribosome. Using quantitative proteomics and western blot analysis on patient fibroblasts, we demonstrated a loss of MRPL50 protein and an associated destabilisation of the large subunit of the mitochondrial ribosome whilst the small subunit was preserved. The mitochondrial ribosome is responsible for the translation of subunits of the mitochondrial oxidative phosphorylation machinery, and we found patient fibroblasts have a mild but significant decrease in the abundance of mitochondrial complex I. These data support a biochemical phenotype associated with MRPL50 variants. We validated the association of MRPL50 with the clinical phenotype by knockdown/knockout of mRpL50 in Drosophila, which resulted abnormal ovarian development. In conclusion, we have shown that a MRPL50 missense variant destabilises the mitochondrial ribosome, leading to oxidative phosphorylation deficiency and syndromic POI, highlighting the importance of mitochondrial support in ovarian development and function.

Clinical, Hormonal, and Genetic Spectrum of 46 XY Disorders of Sexual Development (DSD) Patients.

OBJECTIVES: To evaluate the clinical, hormonal and genetic characteristics of 46XY disorders of sexual development (DSD) patients from South India. METHODS: 46XY DSD patients with a provisional diagnosis of 17ß-hydroxysteroid dehydrogenase 3 (17BHSD3) deficiency, 5 alpha-reductase type 2 deficiency (5ARD2) or partial androgen insensitivity syndrome (PAIS) based on clinical and hormonal analysis were included in this study. All the patients underwent detailed clinical and hormonal evaluations. Targeted next-generation sequencing for all three genes (AR, HSD17B3, and SRD5A2) in parallel was carried out for all the included patients and their parents. RESULTS: Based upon the clinical and hormonal analysis, among the 37 children with 46XY DSD in the present study, 21 children were diagnosed with 5ARD2, 10 with PAIS, and six with 17BHSD3 deficiency. However, genetic analysis revealed pathogenic mutations in nine patients - six in the AR gene, two in the SRD5A2 gene, and one in the HSD17B3 gene. The concordance rate between provisional hormonal and genetic diagnosis was only 22.2%. Two out of six subjects with AR gene variants were positive for somatic mosaicism. CONCLUSIONS: In the present study, a positive genetic diagnosis was detected in nine patients (24%), including five novel variants. In this study, mutations in the AR gene was the most reported. The authors did not find the testosterone: dihydrotestosterone (T: DHT) ratio to be an accurate hormonal diagnostic tool.

Insulin Sensitivity, Islet Cell Function, and Incretin Axis in Pregnant Women With and Without Gestational Diabetes Mellitus.

Introduction: The aim of this study was to compare insulin sensitivity, islet cell function, and incretin axes in pregnant subjects with GDM and normal healthy controls. Methods: Pregnant women at 24 to 28 weeks of gestation were subjected to a 75 g oral glucose tolerance test (OGTT). Samples for glucose, insulin, glucagon, glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) were collected at 0, 30, 60, and 120 min during the OGTT. The Matsuda index (MI) and insulin secretion and sensitivity index-2 (ISSI-2) were assessed. The glucagon suppression index (GSI) was calculated along with the area under the curve (AUC) for glucose, insulin, glucagon, GLP-1, and GIP. Results: A total of 48 pregnant women (25 GDM and 23 controls) were finally analysed. The MI and ISSI-2 were low in the GDM group [4.31 vs. 5.42; P = 0.04], [1.99 vs. 3.18, P ≤ 0.01] respectively). Total AUCglucagon was higher in the GDM group (7411.7 vs. 6320.1, P = 0.02). GSI30 was significantly lower in the GDM group (-62.6 vs. -24.7, P = 0.03). Fasting GLP-1 levels were low in GDM women (17.3 vs. 22.2, P = 0.04). The total AUCGLP-1 positively correlated with total GSI in the GDM group. Conclusion: Asian-Indian GDM women have high insulin insensitivity, islet cell dysfunction, and low fasting GLP-1. Incretin axis dysfunction plays a potential role in their islet cell dysfunction.

Effect of a single dose of zoledronic acid on bone mineral density and trabecular bone score in Indian postmenopausal osteoporotic women with and without type 2 diabetes mellitus - A prospective cohort pilot study.

PURPOSE: The objectives were to study the effect of a single dose of intravenous (IV) zoledronic acid (ZA) on changes in bone mineral density (BMD) (lumbar spine (LS), hip, & distal forearm), trabecular bone score (TBS) and bone turnover markers (BTMs) in postmenopausal osteoporotic women with and without diabetes over 12 months. METHODS: Patients were divided into two groups: type 2 diabetes mellitus (T2DM) (n = 40) and non-DM (n = 40). Both groups received a single dose of 4 mg IV ZA at baseline. The BMD with TBS and BTMs (ß-CTX, sclerostin, P1NP) were measured at baseline, six months, and 12 months. RESULTS: At baseline, BMD in all three sites was similar in both groups. T2DM patients were older and had lower BTMs than non-DM patients. The mean increase in LS-BMD (gram/cm2) at 12 months in T2DM and the non-DM group was 3.6 ± 4.7% and 6.2 ± 4.7 %, respectively (P = 0.01). However, the age adjusted mean difference in LS BMD increment between two groups at one year was - 2.86 % (-5.02% to -0.69%), P = 0.01. There was a comparable change in BMD at other two sites, BTMs, and TBS in both the groups over one year follow-up. CONCLUSION: The gain in the LS-BMD was significantly lower in T2DM group compared to non-DM subjects over 12 months after a single IV infusion of 4 mg ZA. The explanation for this could be low bone turnover in diabetes subjects at baseline.

Dipeptidyl peptidase 4 inhibitors in COVID-19: Beyond glycemic control.

Coronavirus disease 2019 (COVID-19) is associated with a high risk of mortality and complications in patients with diabetes mellitus. Achieving good glycemic control is very important in diabetic patients to reduce complications and mortality due to COVID-19. Recent studies have shown the mortality benefit and anti-inflammatory effects of Dipeptidyl-peptidase-4 inhibitors (DPP-4i) in diabetic patients with COVID-19. DPP-4i may have a beneficial role in halting the severity of infection primarily by three routes, namely viral entry inhibition, anti-inflammatory and anti-fibrotic effects and glycemic control. This has raised the pro-mising hypothesis that DPP-4i might be an optimal strategy for treating COVID-19 in patients with diabetes. This review aims to summarise the possible therapeutic non-glycemic effects of DPP-4i in diabetic patients diagnosed with COVID-19 in the light of available evidence.

Pituitary Dysfunction Following Snakebite Envenomation: A Clinico-Radiological Assessment of 15 Cases and Review of the Literature.

Background: Snakebite envenomation (SE) is an important tropical disease in India, causing significant morbidity and mortality among patients. The hormonal deficiencies due to the involvement of the pituitary in case of SE can present in either acute or delayed setting. Hypopituitarism (HP) is often an underrecognized and relatively rarely reported complication of this neglected disease. Methods: We present here the data of 15 patients diagnosed to have HP following systemic SE and are being currently followed-up in the Endocrinology outpatient department of a tertiary care hospital of South India. The study was approved by the Institute ethics committee, and informed onsent was taken from all the study patients. The study was a record-based retrospective analysis of the patients with HP following SE. Clinical data including lag time in diagnosis and type of snake were determined. Further, hormonal data including all the anterior pituitary functions (thyroid stimulating hormone, free T4, cortisol, insulin-like growth factor (IGF-1) luteinizing hormone, follicular-stimulating hormone, testosterone; prolactin) and water deprivation test to determine diabetes insipidus (DI) in patients with polyuria on follow-up were extracted from the records and the hospital information system. An experienced neuroradiologist examined the magnetic resonance imaging (MRI) findings of the pituitary. Results: The mean age of the patients was 43 ± 9 years and 80% were male. Around 90% of patients belonged to upper-lower socioeconomic status according to the modified Kuppuswamy scale. The commonest snake species reported was Russell's viper. Thirteen patients had delayed HP. The median duration from snakebite to onset of HP symptoms was 1 year (range 0.33-10 years). However, the median time from snakebite to the diagnosis of HP was 7 years (range 1-13 years). Central hypothyroidism and hypogonadism were present in all subjects. However, central hypocortisolism was noted in 93% of patients. Low IGF-1 was noted in all the six patients where data were available. One patient had partial central DI. Thirteen out of 15 patients had reduction of pituitary volume in MRI. Conclusion: HP in patients with SE can appear slowly and the diagnosis is frequently delayed for years. Following snakebite, multiple pituitary hormone deficiencies associated with radiological abnormalities like a significant reduction in the pituitary volume are common.

Dipeptidyl peptidase-4 inhibitor-induced autoimmune diseases: Current evidence.

Dipeptidyl peptidase-4 inhibitors (DPP-4i) have an important place in the management of type 2 diabetes. The DPP-4 enzyme is ubiquitously distributed throughout the human body and has multiple substrates through which it regulates several important physiological functions. DPP-4 regulates several immune functions, including T-cell activation, macrophage function, and secretion of cytokines. Studies have reported an increase in autoimmune diseases like bullous pemphigoid, inflammatory bowel disease, and arthritis with DPP-4i use. The relationship of DPP-4i and autoimmune diseases is a complex one and warrants further research into the effect of DPP-4 inhibition on the immune system to understand the pathogenesis more clearly. Whether a particular cluster of autoimmune diseases is associated with DPP-4i use remains an important contentious issue. Nevertheless, a heightened awareness from the clinicians is required to identify and treat any such diseases. Through this review, we explore the clinical and pathophysiological characteristics of this association in light of recent evidence.

Pediatric Adrenocortical Oncocytoma presenting as Cushing's Syndrome and Peripheral Precocious Puberty: A Case Report and Review of Literature.

Oncocytic adrenocortical tumours (OATs) or oncocytomas are extremely rare and are usually benign and nonfunctional. We report the case of a 4-year-old male with a right-sided, functional oncocytic adrenocortical adenoma, who presented with precocious puberty and Cushing's syndrome. After work-up, the patient underwent laparoscopic adrenalectomy. The excised adrenal mass weighed 21 g and measured 3.5 cm in maximum dimension. Histological examination demonstrated no features suggestive of aggressive biological behaviour. The patient had no features of recurrent or metastatic disease and had prepubertal testosterone levels with suppressed hypothalamic-pituitary-adrenal axis twelve months after the surgery. A discussion of this case and a review of the literature on functional OATs in the pediatric population are presented.

The Risk of Fractures in Primary Hyperparathyroidism: A Meta-Analysis.

Primary hyperparathyroidism (PHPT) is a common metabolic bone disease affecting 1% of the adult population. Patients with PHPT have reduced BMD, especially at the cortical bone. However, studies evaluating its impact on fracture risk have shown contradictory results. In an effort to further inform fracture risk for this patient population, a meta-analysis of studies of fracture in patients with PHPT compared with a control population was undertaken. Articles were searched in PubMed/MEDLINE, Excerpta Medica, Cochrane Central Register of Controlled Trials, Latin American and Caribbean Health Sciences Literature, and Web of Science bibliographic databases. The meta-analysis included 17 studies involving 3807 PHPT cases and 11,908 controls. The primary outcome was to determine the risk of vertebral fracture (VF), nonvertebral fracture, hip fracture, distal radius fracture, and total fracture (TF) among patients with PHPT in comparison with a control population. BMD (lumbar spine, femoral neck, total hip, and distal radius) and serum 25-hydroxy vitamin D level, as well as possible predictors of VF as secondary outcomes were assessed. From this meta-analysis, it was found that there was a significantly increased risk of VF (risk ratio [RR], 2.57; 95% CI, 1.3-5.09; p = 0.007) and TF (RR, 1.71; 95% CI, 1.48-1.97; p < 0.00001) in patients with PHPT. There was a significant decrease in BMD in patients with PHPT versus controls at all four sites. Older age, longer duration since menopause, and lower BMD at lumbar spine and distal radius were predictors for VF. To conclude, patients with PHPT had a significantly higher risk for VF and TF in comparison with controls. © 2021 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

Comparison of islet cell function, insulin sensitivity, and incretin axis between Asian-Indians with either impaired fasting glucose or impaired glucose tolerance, and normal healthy controls.

AIMS: The objective of this study was to compare the islet cell function, insulin sensitivity, and incretin axis between Asian-Indian subjects with either impaired fasting glucose (IFG), or impaired glucose tolerance (IGT), and normal glucose tolerance (NGT). MATERIALS AND METHODS: Prediabetes subjects underwent a mixed meal tolerance test(MMTT) after overnight fasting. Samples for glucose, insulin, glucagon, and glucagon-like peptide-1 (GLP-1) were collected at 0, 30, 60, and 120 min. Insulin secretion sensitivity index -2 (ISSI-2) for beta-cell function and Matsuda index for insulin sensitivity were assessed. Alpha cell function was assessed by measuring the area under the curve (AUC) 0-120 glucagon/AUC0-120 glucose. RESULTS: A total of sixty subjects were recruited with 20 in each group. The beta-cell function represented by ISSI-2 was impaired in prediabetes subjects as compared to NGT group (IFG: 2.09 ± 0.44 vs. NGT: 3.04 ± 0.80, P < 0.0001, and IGT: 2.33 ± 0.59 vs. NGT: 3.04 ± 0.80, P = 0.002). Similarly, AUC0-120 glucagon/AUC0-120 glucose was also lower in prediabetes group as compared to healthy controls (IFG: 0.41(0.54) vs. NGT: 1.07(0.39), P = 0.003 and IGT: 0.57(0.38) vs. NGT: 1.07(0.39), P = 0.001). CONCLUSION: Asian-Indian prediabetes subjects have reduced beta-cell function with lesser glucagon secretion during MMTT as compared to normal healthy controls.