A model to explore the interaction between muscle insulin resistance and beta-cell dysfunction in the development of type 2 diabetes

Type 2 diabetes is a polygenic disease characterized by defects in both insulin secretion and insulin action. We have previously reported that isolated insulin resistance in muscle by a tissue-specific insulin receptor knockout (MIRKO mouse) is not sufficient to alter glucose homeostasis, whereas beta-cell-specific insulin receptor knockout (betaIRKO) mice manifest severe progressive glucose intolerance due to loss of glucose-stimulated acute-phase insulin release. To explore the interaction between insulin resistance in muscle and altered insulin secretion, we created a double tissue-specific insulin receptor knockout in these tissues. Surprisingly, betaIRKO-MIRKO mice show an improvement rather than a deterioration of glucose tolerance when compared to betaIRKO mice. This is due to improved glucose-stimulated acute insulin release and redistribution of substrates with increased glucose uptake in adipose tissue and liver in vivo, without a significant decrease in muscle glucose uptake. Thus, insulin resistance in muscle leads to improved glucose-stimulated first-phase insulin secretion from beta-cells and shunting of substrates to nonmuscle tissues, collectively leading to improved glucose tolerance. These data suggest that muscle, either via changes in substrate availability or by acting as an endocrine tissue, communicates with and regulates insulin sensitivity in other tissues.     

Is Transforming Stem Cells to Pancreatic Beta Cells Still the Holy Grail for Type 2 Diabetes?

Diabetes is a progressive disease affecting millions of people worldwide. There are several medications and treatment options to improve the life quality of people with diabetes. One of the strategies for the treatment of diabetes could be the use of human pluripotent stem cells or induced pluripotent stem cells. The recent advances in differentiation of stem cells into insulin-secreting beta-like cells in vitro make the transplantation of the stem cell-derived beta-like cells an attractive approach for treatment of type 1 and type 2 diabetes. While stem cell-derived beta-like cells provide an unlimited cell source for beta cell replacement therapies, these cells can also be used as a platform for drug screening or modeling diseases.     

Psychological distress,health and treatment-related factors among individuals initiating ART in Oromia,Ethiopia

HIV diagnosis may be a source of psychological distress. Late initiation of antiretroviral therapy (ART) and treatment-related beliefs may intensify psychological distress among those recently diagnosed. This analysis describes the prevalence of psychological distress among people living with HIV (PLWH) and examines the association of recent HIV diagnosis, late ART initiation and treatment-related beliefs with psychological distress. The sample includes 1175 PLWH aged 18 or older initiating ART at six HIV clinics in Ethiopia. Psychological distress was assessed with Kessler Psychological Distress Scale. Scores?≥?29 were categorized as severe psychological distress. Individuals who received their first HIV diagnosis in the past 90 days were categorized as recently diagnosed. Multivariable logistic regression modeled the association of recent diagnosis, late ART initiation and treatment-related beliefs on severe psychological distress, controlling for age, sex, education, area of residence, relationship status, and health facility. Among respondents, 29.5% reported severe psychological distress, 46.6% were recently diagnosed and 31.0% initiated ART late. In multivariable models, relative to those who did not initiate ART late and had longer time since diagnosis, odds of severe psychological distress was significantly greater among those with recent diagnosis and late ART initiation (adjusted OR [aOR]: 1.9 [95% CI 1.4, 2.8]). Treatment-related beliefs were not associated with severe psychological distress in multivariable models. Severe psychological distress was highly prevalent, particularly among those who were recently diagnosed and initiated ART late. Greater understanding of the relationship between psychological distress, recent diagnosis, and late ART initiation can inform interventions to reduce psychological distress among this population. Mental health screening and interventions should be incorporated into routine HIV clinical care from diagnosis through treatment.