Accelerated whole-body protein catabolism in subjects with type 2 Diabetes Mellitus and albuminuria

Endocrine islet β-cell subtypes with differential function are derived from biochemically distinct embryonic endocrine islet progenitors that are regulated by maternal nutrients

Endocrine islet b cells comprise heterogenous cell subsets. Yet when/how these subsets are produced and how stable they are remain unknown. Addressing these questions is important for preventing/curing diabetes, because lower numbers of b cells with better secretory function is a high risk of this disease. Using combinatorial cell lineage tracing, scRNA-seq, and DNA methylation analysis, we show here that embryonic islet progenitors with distinct gene expression and DNA methylation produce b-cell subtypes of different function and viability in adult mice. The subtype with better function is enriched for genes involved in vesicular production/trafficking, stress response, and Ca2+-secretion coupling, which further correspond to differential DNA methylation in putative enhancers of these genes. Maternal overnutrition, a major diabetes risk factor, reduces the proportion of endocrine progenitors of the b-cell subtype with better-function via deregulating DNA methyl transferase 3a. Intriguingly, the gene signature that defines mouse b-cell subtypes can reliably divide human cells into two sub-populations while the proportion of b cells with better-function is reduced in diabetic donors. The implication of these results is that modulating DNA methylation in islet progenitors using maternal food supplements can be explored to improve b-cell function in the prevention and therapy of diabetes.

Blood-Biomarkers for Glucose Metabolism in Preterm Infants

This was an exploratory, prospective, longitudinal, cohort study that aimed to establish "healthy" reference levels related to growth parameters and glucose metabolites in preterm infants. This was conducted to further investigate growth and metabolic disturbances potentially related to neonatal illness. The study sample consisted of 108 preterm infants born before 32 weeks in 2018-2019 in the Capital Region of Denmark. Repetitive blood samples were acquired at the neonatal wards, while clinical data were obtained from the regional hospital medical record system. Thirty-four "healthy" preterm infants (31%) were identified. The "ill" infants were divided into four subgroups dependent on gestational age and small for gestational age. Reference levels for the growth parameters and metabolic biomarkers glucose, albumin, and adiponectin, and two glucose control indicators, glycated albumin and fructosamine, were determined for the "healthy" and "ill" subgroups. The "ill" extremely preterm infants had increased glucose levels (mean difference 0.71 mmol/L, 95% CI 0.23; 1.18 mmol/L) and glycated albumin (corrected; %) (mean difference 0.92 mmol/L, 95% CI 0.38 mmol/L;1.47 mmol/L) compared to the "healthy" infants. In "ill" extremely preterm infants and "ill" very preterm infants born small for gestational age, levels of biomarkers containing proteins were decreased. In the "Ill" extremely preterm infants and infants born small for gestational age, postnatal growth was continuously decreased throughout the postconceptional period. The short-term glucose-control indicator, glycated albumin (corrected; %), reflected well the high glucose levels due to its correction for the depleted plasma-protein pool.

Evaluation of Antidiabetic and Antihyperlipidemic Activity of 80% Methanolic Extract of the Root of Solanum incanum Linnaeus (Solanaceae) in Mice

Background

Conventional antidiabetic drugs are linked with a number of contraindications and untoward effects. The root decoction of Solanum incanum L. has traditionally been used to treat diabetes. However, its safety and efficacy have not been scientifically authenticated yet. Hence, the study was conducted in mice to corroborate its antidiabetic potential and safety profile.

Methods

Using normoglycemic, oral glucose-loaded, and streptozotocin-induced diabetic mice models, the hypoglycemic and antihyperglycemic activities of 80% methanolic root extract were investigated. On streptozotocin-induced diabetic mice, the effect of the test extract on diabetic lipid profile and body weight was also investigated. Further, the in vitro α-amylase inhibition activity was assessed.

Results

The test extract was safe at a limit test dose of 2 g/kg. Dose-dependent α-amylase inhibition activity was seen with peak percentage inhibition of 75.95% at 700 μg/mL. In normoglycemic mice, the plant extract showed statistically significant hypoglycemic activity at 200 and 400 mg/kg (P < 0.001) at 6  h and 4 and 6 h of treatment, respectively; in oral glucose-loaded mice, at both the test doses, the glucose level was also significantly dropped at 120 (P < 0.01) and 60 and 120 min (P < 0.001), respectively; whereas, in the third model, the test extract showed significant antihyperglycemic activity at 100 mg/kg (P < 0.05) on the 14^th day and at 200 (P < 0.01) and 400 mg/kg (P < 0.001) on the 7^th and 14^th day of treatment. Similarly, following repeated administration of the test extract at 200 and 400 mg/kg, the body weight was significantly improved on the 14^th day (P < 0.05) and on the 7^th and 14^th day (P < 0.01), respectively, while diabetic dyslipidemia after 14 days (P < 0.05).

Conclusion

The study revealed that the test extract showed promising antihyperglycemic and antihyperlipidemic activity. Thus, the findings back up its use in Ethiopian remedies for diabetes.

How to Overcome Anabolic Resistance in Dialysis-Treated Patients?

A current hypothesis is that dialysis-treated patients are "anabolic resistant" i. e., their muscle protein synthesis (MPS) response to anabolic stimuli is blunted, an effect which leads to muscle wasting and poor physical performance in aging and in several chronic diseases. The importance of maintaining muscle mass and MPS is often neglected in dialysis-treated patients; better than to describe mechanisms leading to energy-protein wasting, the aim of this narrative review is to suggest possible strategies to overcome anabolic resistance in this patient's category. Food intake, in particular dietary protein, and physical activity, are the two major anabolic stimuli. Unfortunately, dialysis patients are often aged and have a sedentary behavior, all conditions which per se may induce a state of "anabolic resistance." In addition, patients on dialysis are exposed to amino acid or protein deprivation during the dialysis sessions. Unfortunately, the optimal amount and formula of protein/amino acid composition in supplements to maximixe MPS is still unknown in dialysis patients. In young healthy subjects, 20 g whey protein maximally stimulate MPS. However, recent observations suggest that dialysis patients need greater amounts of proteins than healthy subjects to maximally stimulate MPS. Since unneccesary amounts of amino acids could stimulate ureagenesis, toxins and acid production, it is urgent to obtain information on the optimal dose of proteins or amino acids/ketoacids to maximize MPS in this patients' population. In the meantime, the issue of maintaining muscle mass and function in dialysis-treated CKD patients needs not to be overlooked by the kidney community.