A role for von Hippel-Lindau protein in pancreatic beta-cell function.

ObjectiveThe Vhlh gene codes for the von Hippel-Lindau protein (VHL), a tumor suppressor that is a key player in the cellular response to oxygen sensing. In humans, a germline mutation in the VHL gene leads to the von Hippel-Lindau disease, a familial syndrome characterized by benign and malignant tumors of the kidney, central nervous system, and pancreas.Research design and methodsWe use Cre-lox recombination to eliminate Vhlh in adult mouse pancreatic beta-cells. Morphology of mutant islets is assessed by immunofluorescence analysis. To determine the functional state of Vhlh(-/-) islets, insulin secretion is measured in vivo and in vitro, and quantitative PCR is used to identify changes in gene expression.ResultsLoss of VHL in beta-cells leads to a severe glucose-intolerant phenotype in adult animals. Although VHL is not required for beta-cell specification and development, it is critical for beta-cell function. Insulin production is normal in beta-cells lacking VHL; however, insulin secretion in the presence of high concentrations of glucose is impaired. Furthermore, the loss of VHL leads to dysregulation of glycolytic enzymes, pointing to a perturbation of the intracellular energy homeostasis.ConclusionsWe show that loss of VHL in beta-cells leads to defects in glucose homeostasis, indicating an important and previously unappreciated role for VHL in beta-cell function. We believe that the beta-cell-specific Vhlh-deficient mice might be a useful tool as a "genetic hypoxia" model, to unravel the possible link between hypoxia signaling and impairment of beta-cell function

Dynamics of embryonic pancreas development using real-time imaging

AbstractCurrent knowledge about developmental processes in complex organisms has relied almost exclusively on analyses of fixed specimens. However, organ growth is highly dynamic, and visualization of such dynamic processes, e.g., real-time tracking of cell movement and tissue morphogenesis, is becoming increasingly important. Here, we use live imaging to investigate expansion of the embryonic pancreatic epithelium in mouse. Using time-lapse imaging of tissue explants in culture, fluorescently labeled pancreatic epithelium was found to undergo significant expansion accompanied by branching. Quantification of the real-time imaging data revealed lateral branching as the predominant mode of morphogenesis during epithelial expansion. Live imaging also allowed documentation of dynamic β-cell formation and migration. During in vitro growth, appearance of newly formed β-cells was visualized using pancreatic explants from MIP-GFP transgenic animals. Migration and clustering of β-cells were recorded for the first time using live imaging. Total β-cell mass and concordant aggregation increased during the time of imaging, demonstrating that cells were clustering to form “pre-islets”. Finally, inhibition of Hedgehog signaling in explant cultures led to a dramatic increase in total β-cell mass, demonstrating application of the system in investigating roles of critical embryonic signaling pathways in pancreas development including β-cell expansion. Thus, pancreas growth in vitro can be documented by live imaging, allowing visualization of the developing pancreas in real-time

The role of trans obturator tape as a surgical procedure for female stress urinary incontinence and its impact on quality of life in Jammu region

Background: Stress incontinence is one of the most common but debilitating health issue among women. It has a detrimental effect on overall health and quality of life of women. Trans obturator tape (TOT) has emerged as a promising treatment modality. The aim of present study was to assess the usefulness of TOT in terms of change in quality of life of stress incontinence patients.Methods: The study was performed at Department of Obstetrics and Gynecology, Acharya Shri Chandler of Medical Sciences (ASCOMS), Jammu. A total of 50 symptomatic women were enrolled in the study and underwent TOT procedure using outside-in technique. The quality of life of women was assessed at enrolment and 12 months after the procedure using King’s Health Questionnaire (KHQ). Change in QOL was assessed using paired ‘t’-test.Results: After 12 months follow-up, a total of 27 (54%) patients were entirely symptom free. As compared to pre-treatment QOL assessment on KHQ for general health/incontinence impact, quality of life and symptom scores a % decline of 73.2%, 79.8% and 78.4% was observed. For all the three parts, the change in scores was significant statistically. No other complications and side effects were reported.Conclusions: TOT is a useful procedure which provided symptomatic relief as well as QOL enhancement

A comparative study of insulin levels in lean versus obese polycystic ovarian syndrome patients

Background: Polycystic ovary syndrome (PCOS) is one of the most common endocrine disorders in women of reproductive age group. PCOS has been frequently associated with insulin resistance and obesity. Although most of the cases with PCOS are obese or overweight, a significant proportion of patients have normal body mass index (BMI≤25 kg/m2) that makes diagnostic work up and therapeutic approach more difficult. These cases are referred to as “lean PCOS.” Methods: This hospital based prospective, comparative cross-sectional study was conducted to estimate the insulin levels and insulin resistance in lean versus over-weight or obese PCOS patients and to evaluate the correlation of BMI with clinical parameters, serum insulin levels, and hormone profile in these patients. Patients were grouped according to their BMI: Lean group-(n=46) BMI<25 kg/m2 and obese group-(n=40) BMI≥25 kg/m2. Results: Serum insulin levels in obese PCOS patients were significantly higher than in lean PCOS patients (p<0.001). Overweight or obese PCOS women achieved significantly higher HOMA-IR than lean PCOS patients (p<0.001). The difference in fasting blood sugar levels in lean versus obese PCOS patients were not significantly different. Comparisons of the two groups showed no statistical differences in gonadotrophins (LH and FSH) values and LH/FSH ratio. The serum testosterone level was significantly higher in the obese group compared with the lean group (p=0.043). Conclusions: We conclude that the overweight/obese PCOS patients had higher tendency to develop insulin resistance and elevated fasting insulin levels as compared to their lean counterparts. Thus, weight reduction and metformin therapy hold great potential in managing a patient with insulin resistance in PCOS but will not have much effect on hormonal profile of a patient with PCOS but will not have much effect on hormonal profile of a patient with PCOS

Long term follow-up study for abdominal sacrocolpopexy/sacrohysteropexy

Background: Pelvic organ prolapse is common in women and 7-9% undergo surgical repair. Abdominal sacrocolpopexy and sacrohysteropexy is the most durable operation for vault prolapse and Nulliparous prolapse respectively. The objectives of this study were to describe Anatomic and symptomatic outcomes up to 5 years after abdominal sacrocolpopexy or sacrohysteropexy.Methods: This study was conducted in ASCOMS hospital for a cohort of patients who underwent abdominal sacrocolpopexy (ASC) or sacrohysteropexy (ASH) in 2 years (2013-2015) and follow up done for a period of 5 years from 2015-2019. These patients were evaluated for subjective and objective outcomes following ASC and ASH. women completed questionnaires and were examined in gynaecology clinic. Prospective follow up study using standarised examination with pelvic organ prolapse quantification system (POP-Q) and questionnairesResults: In the present study, there was low incidence of intraoperative and postoperative complications as well as long term complications were significantly low. The anatomical cure rate and patient satisfaction rate was both 100%.Conclusions: Abdominal sacrocolpopexy for vault prolapse and sacrohysteropexy for Nulliparous prolapse is safe and effective method and is considered gold standard for treatment of Apical compartment prolapse

Consequences of a missed history: A case of antidepressant discontinuation syndrome

Antidepressant discontinuation syndrome (ADDS) is reported to occur in almost 30-50% of the patients who take antidepressants for a duration of at least four to six weeks and then suddenly discontinue the drug. Since there is an increase in the use of antidepressants for various reasons by general practitioners, patient education about when and how to discontinue a drug is not acknowledged enough. It is reported to occur with the use of different classes of antidepressants - selective serotonin reuptake inhibitor (SSRI), monoamineoxidase inhibitor (MAOI), tricyclic antidepressants (TCAs), and atypical antipsychotics like risperidone, trazodone, clozapine, and venlafaxine. Slow tapering off the drugs has also caused ADDS. Symptoms start within two to four days of quitting the drug and are usually mild lasting for two to four weeks (can persist for six to 12 months) but could be severe enough leaving the patient nonambulatory. Here, we represent a case of a 55-year-old female who presented to the outpatient clinic with complaints of headache, vomiting, and diarrhea. The patient had 10 to 12 episodes of watery diarrhea every day and bilateral, continuous, pressing headache associated with multiple episodes of non-projectile vomiting. She was investigated for ultrasound sonography (USG) abdomen, CT head, and lab investigations which turned around to be normal. A follow-up visit with detailed history revealed she suddenly stopped taking escitalopram after six months by herself without tapering off the dose, two days before the onset of symptoms. Escitalopram was reinstated and the symptoms started to resolve in two to three days. All the unnecessary investigations and treatment could have been prevented if the proper history was taken and revealed at the initial visit

Loss of pancreas upon activated Wnt signaling is concomitant with emergence of gastrointestinal identity

Organ formation is achieved through the complex interplay between signaling pathways and transcriptional cascades. The canonical Wnt signaling pathway plays multiple roles during embryonic development including patterning, proliferation and differentiation in distinct tissues. Previous studies have established the importance of this pathway at multiple stages of pancreas formation as well as in postnatal organ function and homeostasis. In mice, gain-of-function experiments have demonstrated that activation of the canonical Wnt pathway results in pancreatic hypoplasia, a phenomenon whose underlying mechanisms remains to be elucidated. Here, we show that ectopic activation of epithelial canonical Wnt signaling causes aberrant induction of gastric and intestinal markers both in the pancreatic epithelium and mesenchyme, leading to the development of gut-like features. Furthermore, we provide evidence that β -catenin-induced impairment of pancreas formation depends on Hedgehog signaling. Together, our data emphasize the developmental plasticity of pancreatic progenitors and further underscore the key role of precise regulation of signaling pathways to maintain appropriate organ boundaries

Replication confers β cell immaturity.

Pancreatic β cells are highly specialized to regulate systemic glucose levels by secreting insulin. In adults, increase in β-cell mass is limited due to brakes on cell replication. In contrast, proliferation is robust in neonatal β cells that are functionally immature as defined by a lower set point for glucose-stimulated insulin secretion. Here we show that β-cell proliferation and immaturity are linked by tuning expression of physiologically relevant, non-oncogenic levels of c-Myc. Adult β cells induced to replicate adopt gene expression and metabolic profiles resembling those of immature neonatal β that proliferate readily. We directly demonstrate that priming insulin-producing cells to enter the cell cycle promotes a functionally immature phenotype. We suggest that there exists a balance between mature functionality and the ability to expand, as the phenotypic state of the β cell reverts to a less functional one in response to proliferative cues

Controlled induction of human pancreatic progenitors produces functional beta‐like cells in vitro

Directed differentiation of human pluripotent stem cells into functional insulin‐producing beta‐like cells holds great promise for cell replacement therapy for patients suffering from diabetes. This approach also offers the unique opportunity to study otherwise inaccessible aspects of human beta cell development and function in vitro. Here, we show that current pancreatic progenitor differentiation protocols promote precocious endocrine commitment, ultimately resulting in the generation of non‐functional polyhormonal cells. Omission of commonly used BMP inhibitors during pancreatic specification prevents precocious endocrine formation while treatment with retinoic acid followed by combined EGF/KGF efficiently generates both PDX1+ and subsequent PDX1+/NKX6.1+ pancreatic progenitor populations, respectively. Precise temporal activation of endocrine differentiation in PDX1+/NKX6.1+ progenitors produces glucose‐responsive beta‐like cells in vitro that exhibit key features of bona fide human beta cells, remain functional after short‐term transplantation, and reduce blood glucose levels in diabetic mice. Thus, our simplified and scalable system accurately recapitulates key steps of human pancreas development and provides a fast and reproducible supply of functional human beta‐like cells.SynopsisFocusing on developmental mechanisms, the results of this study further accelerate successful differentiation of human ESCs into functional pancreatic beta cells.Exclusion of commonly used BMP inhibitors during human embryonic stem cell to pancreatic progenitor differentiation prevents precocious endocrine induction.Sequential exposure of foregut cells to retinoic acid followed by combined EGF/KGF treatment establishes highly pure PDX1+ and PDX1+/NKX6.1+ progenitor populations, respectively.Precise temporal induction of endocrine differentiation in PDX1+/NKX6.1+ progenitors, but not in PDX1+/NKX6.1− progenitors, results in the generation of functional beta‐like cells in vitro.Beta‐like cells exhibit key features of bona fide human beta cells, remain functional after short‐term transplantation, and reduce blood glucose levels in diabetic mice.Focusing on developmental mechanisms, the results of this study further accelerate successful differentiation of human ESCs into functional pancreatic beta cells.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/111932/1/embj201591058.reviewer_comments.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/111932/2/embj201591058.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/111932/3/embj201591058-sup-0001-FigsS1-S4.pd

PDX1 dynamically regulates pancreatic ductal adenocarcinoma initiation and maintenance

Aberrant activation of embryonic signaling pathways is frequent in pancreatic ductal adenocarcinoma (PDA), making developmental regulators therapeutically attractive. Here we demonstrate diverse functions for pancreatic and duodenal homeobox 1 (PDX1), a transcription factor indispensable for pancreas development, in the progression from normal exocrine cells to metastatic PDA. We identify a critical role for PDX1 in maintaining acinar cell identity, thus resisting the formation of pancreatic intraepithelial neoplasia (PanIN)-derived PDA. Upon neoplastic transformation, the role of PDX1 changes from tumor-suppressive to oncogenic. Interestingly, subsets of malignant cells lose PDX1 expression while undergoing epithelial-to-mesenchymal transition (EMT), and PDX1 loss is associated with poor outcome. This stage-specific functionality arises from profound shifts in PDX1 chromatin occupancy from acinar cells to PDA. In summary, we report distinct roles of PDX1 at different stages of PDA, suggesting that therapeutic approaches against this potential target need to account for its changing functions at different stages of carcinogenesis. These findings provide insight into the complexity of PDA pathogenesis and advocate a rigorous investigation of therapeutically tractable targets at distinct phases of PDA development and progression