Cardiovascular Risk Factors in Sheehan's Syndrome: A Case-Control Study.

Introduction: Obesity, dyslipidaemia and insulin resistance are associated with hypopituitarism. The association between these conditions and Sheehan's syndrome (SS) caused by post-partum pituitary gland necrosis is poorly understood. This study aimed to assess cardiovascular risk surrogate markers in SS patients, and we compared clinical, biochemical and radiological testing with healthy controls. Methods: In this cross-sectional study, we studied 45 patients with SS on standard replacement therapy and compared them with healthy controls. All subjects underwent anthropometric, inflammatory marker and hormonal measurement (adrenocorticotropic hormone (ACTH), stimulated cortisol, insulin-like growth factor-1 (IGF-1), thyroxine (T4), follicle-stimulating hormone (FSH), luteinising hormone (LH), oestradiol (E2), prolactin (Prl), insulin, interleukin-6 (IL-6) and high-sensitivity C-reactive protein (hs-CRP)). Carotid intima-media thickness (CIMT), flow-mediated dilation (FMD) and echocardiography were also performed. Results: The mean age and body mass index (BMI) of SS patients were 48.1 ± 10.0 years and 24.3 ± 4.3 kg/m2, respectively, while those of controls were 44.6 ± 12.0 years and 24.6 ± 3.2 kg/m2, respectively. Systolic blood pressure was significantly higher in SS (124.6 ± 20.8 vs. 117.0 ± 18.6 mm of Hg, P < 0.05). All SS patients were hypothyroid, and all except one were hypocortisolaemic. Triglyceride (TG) levels were significantly higher in SS patients (165.6 ± 83.3 vs. 117.2 ± 56.1, P < 0.01), but no difference in the prevalence of metabolic syndrome (MetS) was found. hs-CRP (9.1 (5.2-18.5) vs. 1.5 (0.6-2.8), P < 0.001) and IL-6 (4.9 (3.7-7.3) vs. 3.1 (2.0-4.2), P < 0.001) were significantly higher in SS patients. CIMT was significantly increased in SS patients, but no difference in FMD was found. Echocardiography revealed no significant difference in left ventricular (LV) dimensions, interventricular thickness, posterior wall thickness, ejection fraction, LV mass and diastolic function. Conclusion: SS patients show increased cardiovascular risk with hypertension, dyslipidaemia and increased atherosclerotic and inflammatory markers.

Spontaneous Hypoglycaemia due to Insulin Autoimmune Syndrome in Six Cases, Response to Steroid Therapy and Rituximab.

Introduction: Dr. Hirata of Japan first described insulin autoimmune syndrome (IAS) in 1970. Seven hundred ninety-five cases of this rare syndrome have been reported from Japan and China and 29 from India. IAS has the following characteristic features 1) severe spontaneous attacks of hyperinsulinemic hypoglycaemia, 2) high total immunoreactive insulin levels, 3) elevated insulin autoantibody (IAA) titres, 4) no prior exposure to exogenous insulin, and 5) no pathological abnormalities of the pancreatic islet cells. Methods: We treated six cases of IAS with high doses of prednisolone for 4-6 weeks and then gradually reduced the doses. Diagnosis of IAS was established by documenting Whipple's triad of symptoms and signs of hypoglycaemia, blood sugar <55 mg/dl, improvement of symptoms with dextrose infusion, inappropriately increased insulin levels >3 uU/ml, C-peptide levels >0.6 ng/ml, and increased titres of anti-insulin autoantibodies. Insulinoma and non-pancreatic tumours were ruled out by CECT (contrast-enhanced computerised tomography) or MRI (magnetic resonance imaging) of the abdomen and if necessary endoscopic ultrasonography and gallium 68 Dotanoc PET (positron enhanced tomography). Autoimmune screening and serum electrophoresis were done to rule out multiple myeloma. Monitoring of the patient's blood sugars was done by the laboratory, glucometer readings, and a freestyle libre glucose monitoring system. Results: Remission of hypoglycaemic episodes, hyperglycaemic episodes, and marked reduction of serum insulin and insulin autoantibodies in four out of six patients with diet therapy and steroids. Two patients resistant to steroids were treated with rituximab successfully. Patient 6 developed serious complications of cytomegalovirus and Pneumocystis carnii after rituximab, which were treated successfully. Conclusion: A careful history including recent infections, medications, and vaccinations provides vital clues in the evaluation. An increased awareness of IAS will prevent unnecessary and costly investigations and surgery. Although it is often self-remitting, steroids are contributory in severe cases. Immunosuppressives are used successfully in cases refractory to steroids. Continuous glucose monitoring system (CGMS), by freestyle libre glucose monitoring system, provided real-time blood sugar values, total time in hypoglycaemia, and total time in the range (TIR), which proved very valuable in managing IAS patients. Low CGMS values should be corroborated clinically and with laboratory or glucometer values.

Postmenopausal women treated for breast cancer with insulin resistance: clinical, analytical, cross-sectional.

This study aims to investigate the potential association between serum levels of cytokines, HSP60, HSP70 and IR (HOMA-IR) in postmenopausal women. We conducted a cross-sectional study involving 381 postmenopausal women, including 94 with a breast cancer diagnosis and 278 without. We analyzed anthropometric and laboratory measurements. Immunoassays were used to measure cytokines (TNF-α, IL-10, and IL-6) as well as heat shock proteins (HSP) 60 and 70 in the serum using the ELISA technique. Women diagnosed with breast cancer showed higher levels of HOMA-IR, IL-6, TNF, and HSP60, and lower levels of IL-10 and HSP70 compared to women without cancer. An association was found between HSP70 and HOMA-IR only in women with breast cancer (ß = 0.22, p = .030; without cancer: ß = 0.04, p = .404), regardless of age, waist circumference, smoking, and physical activity. No associations were observed between cytokines, HSP60, and HOMA-IR in both groups of women. HSP70 is positively associated with IR in women diagnosed with breast cancer.

Unraveling the mechanisms of hepatogenous diabetes and its therapeutic perspectives.

The review focused mainly on the pathogenesis of hepatogenous diabetes (HD) in liver cirrhosis (LC). This review reveals parallels between the mechanisms of metabolic dysfunction observed in LC and type II diabetes (T2DM), suggesting a shared pathway leading to HD. It underscores the role of insulin in HD pathogenesis, highlighting key factors such as insulin signaling, glucose metabolism, insulin resistance (IR), and the influence of adipocytes. Furthermore, the impact of adipose tissue accumulation, fatty acid metabolism, and pro-inflammatory cytokines like Tumor necrosis factor-α (TNF-α) on IR are discussed in the context of HD. Altered signaling pathways, disruptions in the endocrine system, liver inflammation, changes in muscle mass and composition, and modifications to the gut microbiota collectively contribute to the complex interplay linking cirrhosis and HD. This study highlights how important it is to identify and treat this complex condition in cirrhotic patients by thoroughly analyzing the link between cirrhosis, IR, and HD. It also emphasizes the vitality of targeted interventions. Cellular and molecular investigations into IR have revealed potential therapeutic targets for managing and preventing HD.

Type 2 Diabetes Mellitus and Cardiometabolic Prospects: A Rapid Narrative Review.

Cardiometabolic syndrome (CMS), type 2 diabetes mellitus (T2DM), and cardiovascular diseases are among the major altruists to the international liability of disease. The lifestyle and dietary changes attributable to economic growth have resulted in an epidemiological transition towards non-communicable diseases (NCDs) as the leading causes of death. Low- and middle-income countries (LMICs) bear a more substantial disease burden due to limited healthcare sector capacities to address the rapidly growing number of chronic disease patients. The purpose of this narrative review paper was to explore the interrelationships between CMS, T2DM, and cardiovascular impairments in the context of NCDs, as well as major preventative and control interventions. The role of insulin resistance, hyperglycemia, and dyslipidemia in the pathogenesis of T2DM and the development of severe cardiovascular impairments was highlighted. This paper elaborated on the pivotal role of lifestyle modifications, such as healthy diets and physical activity, as cornerstones of addressing the epidemics of metabolic diseases. Foods high in calories, refined sugar, red meat, and processed and ready-to-eat meals were associated with an amplified risk of CMS and T2DM. In contrast, diets based on fruits, legumes, vegetables, and whole grain, home-cooked foods demonstrated protective effects against metabolic diseases. Additionally, the role of a psychological and behavioral approach in addressing metabolic diseases was highlighted, especially regarding its impact on patient empowerment and the patient-centered approach to preventative and therapeutic interventions.

Above the Clouds with Diabetes: From Pathophysiological Considerations to Practical Recommendations for Safe Flights.

Vasdeki, Dimitra, Georgios Tsamos, Kleoniki I. Athanasiadou, Vasiliki Michou, Evangelos Botsarakos, Michael Doumas, Kalliopi Kotsa, and Theocharis Koufakis. Above the clouds with diabetes: From pathophysiological considerations to practical recommendations for safe flights. High Alt Med Biol. 00:00-00, 2024. Background: The prevalence of diabetes mellitus has been following an increasing trend in the last decades, leading to a growing number of travelers with diabetes seeking pretravel advice from medical professionals. Methods: This narrative review summarizes the existing evidence on the intriguing association between diabetes and air travel, analyzes safety and certification protocols, and provides practical recommendations for the management of diabetes during flights. Results: During air travel, individuals with diabetes face challenges arising from inappropriate dietary options, restricted access to medications and healthcare services, disruption of medication dosing intervals, and exposure to hypobaric conditions in the airplane cabin. In addition, people with diabetes, especially those treated with insulin, have traditionally been considered ineligible to become professional pilots. However, this approach gradually changes and numerous countries are now implementing strict protocols to determine the eligibility of pilots with diabetes to operate flights. Conclusions: Given the increasing use of technology and new drugs in daily clinical practice, there is a need for further research in the field to shed light on existing knowledge gaps and ensure safe flights for people with diabetes.

Dietary modulation of microRNAs in insulin resistance and type 2 diabetes.

The prevalence of type 2 diabetes is increasing worldwide. Various molecular mechanisms have been proposed to interfere with the insulin signaling pathway. Recent advances in proteomics and genomics indicate that one such mechanism involves the post-transcriptional regulation of insulin signaling by microRNA (miRNA). These non-coding RNAs typically induce messenger RNA (mRNA) degradation or translational repression by interacting with the 3' untranslated region (3'UTR) of target mRNA. Dietary components and patterns, which can either enhance or impair the insulin signaling pathway, have been found to regulate miRNA expression in both in vitro and in vivo studies. This review provides an overview of the current knowledge of how dietary components influence the expression of miRNAs related to the control of the insulin signaling pathway and discusses the potential application of these findings in precision nutrition.

Fucoxanthin Mitigates High-Fat-Induced Lipid Deposition and Insulin Resistance in Skeletal Muscle through Inhibiting PKM1 Activity.

Glucose and lipid metabolism dysregulation in skeletal muscle contributes to the development of metabolic disorders. The efficacy of fucoxanthin in alleviating lipid metabolic disorders in skeletal muscle remains poorly understood. In this study, we systematically investigated the impact of fucoxanthin on mitigating lipid deposition and insulin resistance in skeletal muscle employing palmitic acid-induced lipid deposition in C2C12 cells and ob/ob mice. Fucoxanthin significantly alleviated PA-induced skeletal muscle lipid deposition and insulin resistance. In addition, fucoxanthin prominently upregulated the expression of lipid metabolism-related genes (Pparα and Cpt-1), promoting fatty acid ß-oxidation metabolism. Additionally, fucoxanthin significantly increased the expression of Pgc-1α and Tfam, elevated the mtDNA/nDNA ratio, and reduced ROS levels. Further, we identified pyruvate kinase muscle isozyme 1 (PKM1) as a high-affinity protein for fucoxanthin by drug affinity-responsive target stability and LC-MS and confirmed their robust interaction by CETSA, microscale thermophoresis, and circular dichroism. Supplementation with pyruvate, the product of PKM1, significantly attenuated the beneficial effects of fucoxanthin on lipid deposition and insulin resistance. Mechanistically, fucoxanthin reduced glucose glycolysis rate and enhanced mitochondrial biosynthesis and fatty acid ß-oxidation through inhibiting PKM1 activity, thereby alleviating lipid metabolic stress. These findings present a novel clinical strategy for treating metabolic diseases using fucoxanthin.

Modulation of naïve mesenchymal stromal cells by extracellular vesicles derived from insulin-producing cells: an in vitro study.

This study was to determine whether extracellular vesicles (EVs) derived from insulin-producing cells (IPCs) can modulate naïve mesenchymal stromal cells (MSCs) to become insulin-secreting. MSCs were isolated from human adipose tissue. The cells were then differentiated to generate IPCs by achemical-based induction protocol. EVs were retrieved from the conditioned media of undifferentiated (naïve) MSCs (uneducated EVs) and from that of MSC-derived IPCs (educated EVs) by sequential ultracentrifugation. The obtained EVs were co-cultured with naïve MSCs.The cocultured cells were evaluated by immunofluorescence, flow cytometry, C-peptide nanogold silver-enhanced immunostaining, relative gene expression and their response to a glucose challenge.Immunostaining for naïve MSCs cocultured with educated EVs was positive for insulin, C-peptide, and GAD65. By flow cytometry, the median percentages of insulin-andC-peptide-positive cells were 16.1% and 14.2% respectively. C-peptide nanogoldimmunostaining providedevidence for the intrinsic synthesis of C-peptide. These cells released increasing amounts of insulin and C-peptide in response to increasing glucose concentrations. Gene expression of relevant pancreatic endocrine genes, except for insulin, was modest. In contrast, the results of naïve MSCs co-cultured with uneducated exosomes were negative for insulin, C-peptide, and GAD65. These findings suggest that this approach may overcome the limitations of cell therapy.

Association between triglyceride-glucose index and gallstones: a cross-sectional study.

This study used data from the National Health and Nutrition Examination Survey (NHANES) to investigate the relationship between the triglyceride-glucose (TyG) index and gallstones. We evaluated the data collected between 2017 to 2020. To evaluate the relationship between TyG index and gallstones, logistic regression analysis, basic characteristics of participants, subgroup analysis, and smooth curve fitting were utilized. The study included 3870 participants over the age of 20 years, 403 of whom reported gallstones, with a prevalence rate of 10.4%. After adjusting for all confounding factors, the risk of gallstones increased by 41% for each unit increase in the TyG index (OR 1.41, 95% CI 1.07, 1.86). The smooth curve fitting also showed a positive correlation between the TyG index and gallstones. Subgroup analysis revealed a significant positive relationship between the TyG index and the risk of gallstones in those aged < 50 years, women, individuals with total cholesterol levels > 200 mg/dL, individuals with body mass index (BMI) > 25, and individuals without diabetes. The risk of gallstones is positively correlated with a higher TyG index. Thus, the TyG index can be used as a predictor of the risk of gallstones.

Single-arm, first-in-human feasibility study results for an ultra-low-cost insulin pump.

BACKGROUND: Use of Continuous Subcutaneous Insulin Infusion (CSII) has been shown to improve glycemic outcomes in Type 1 Diabetes (T1D), but high costs limit accessibility. To address this issue, an inter-operable, open-source Ultra-Low-Cost Insulin Pump (ULCIP) was developed and previously shown to demonstrate comparable delivery accuracy to commercial models in standardised laboratory tests. This study aims to evaluate the updated ULCIP in-vivo, assessing its viability as an affordable alternative for those who cannot afford commercially available devices. METHODS: This first-in-human feasibility study recruited six participants with T1D. During a nine-hour inpatient stay, participants used the ULCIP under clinical supervision. Venous glucose, insulin, and ß-Hydroxybutyrate were monitored to assess device performance. RESULTS: Participants displayed expected blood glucose and blood insulin levels in response to programmed basal and bolus insulin dosing. One participant developed mild ketosis, which was treated and did not recur when a new pump reservoir was placed. All other participants maintained ß-Hydroxybutyrate < 0.6 mmol/L throughout. CONCLUSION: The ULCIP safely delivered insulin therapy to users in a supervised inpatient environment. Future work should focus on correcting a pump hardware issue identified in this trial and extending device capabilities for use in closed loop control. Longer-term outpatient studies are warranted. TRIAL REGISTRATION: The trial was prospectively registered with the Australian New Zealand Clinical Trials Registry (ACTRN12623001288617) on the 11 December 2023.

A systematic review and meta-analysis comparing outcomes between using subcutaneous insulin and continuous insulin infusion in managing adult patients with diabetic ketoacidosis.

BACKGROUND: The purpose of this systematic review and meta-analysis was to synthesize the current literature to determine the safety and efficacy of using subcutaneous insulin compared to an intravenous (IV) insulin infusion in managing diabetic ketoacidosis (DKA). METHODS: We searched Ovid-Medline, EMBASE, SCOPUS, BIOSIS and CENTRAL from inception to April 26, 2024. Randomized controlled trials (RCTs) and observational studies that assessed the use of subcutaneous compared to intravenous insulin for the treatment of mild to moderate DKA were included. Data extraction and quality assessment were performed by two independent reviewers and disagreements were resolved through further discussion or by a third reviewer. The Cochrane Risk of Bias tool version 2.0 was used to evaluate the RCTs and the Risk of Bias in Non-randomized Studies of Interventions (ROBINS)-I tool was used to evaluate the observational studies. The quality of evidence was assessed using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) criteria. Meta-analyses were conducted using random-effects models. We followed the PRISMA guidelines for reporting our findings. RESULTS: Six RCTs (245 participants) and four observational studies (8444 patients) met our inclusion criteria. Some studies showed a decreased length of stay (Mean Difference [MD] in days: -0.39; 95% CI: -2.83 to 2.08; I2: 0%) among individuals treated with subcutaneous insulin compared to intravenous insulin. There was no difference in the risk of all-cause mortality, time to resolution of DKA (MD in hours: 0.17; 95% confidence interval [CI]: -3.45 to 3.79; I2: 0%) and hypoglycemia (Risk Ratio [RR]: 1.02; 95% CI: 0.88 to 1.19; I2: 0%) between the two groups. CONCLUSION: Treatment of DKA with subcutaneous insulin may be a safe and effective alternative to IV insulin in selected patients. The limited available evidence underscores the need for further studies to explore optimal dosing, patient selection criteria and long-term outcomes.

Electronic Glycemic Management System Improved Glycemic Control and Reduced Complications in Patients With Diabetes Undergoing Coronary Artery Bypass Surgery: A Randomized Controlled Trial.

BACKGROUND: In-hospital hyperglycemia poses significant risks for patients with diabetes mellitus undergoing coronary artery bypass graft (CABG) surgery. Electronic glycemic management systems (eGMSs) like InsulinAPP offer promise in standardizing and improving glycemic control (GC) in these settings. This study evaluated the efficacy of the InsulinAPP protocol in optimizing GC and reducing adverse outcomes post-CABG. METHODS: This prospective, randomized, open-label study was conducted with 100 adult type 2 diabetes mellitus (T2DM) patients post-CABG surgery, who were randomized into two groups: conventional care (gCONV) and eGMS protocol (gAPP). The gAPP used InsulinAPP for insulin therapy management, whereas the gCONV received standard clinical care. The primary outcome was a composite of hospital-acquired infections, renal function deterioration, and symptomatic atrial arrhythmia. Secondary outcomes included GC, hypoglycemia incidence, hospital stay length, and costs. RESULTS: The gAPP achieved lower mean glucose levels (167.2 ± 42.5 mg/dL vs 188.7 ± 54.4 mg/dL; P = .040) and fewer patients-day with BG above 180 mg/dL (51.3% vs 74.8%, P = .011). The gAPP received an insulin regimen that included more prandial bolus and correction insulin (either bolus-correction or basal-bolus regimens) than the gCONV (90.3% vs 16.7%). The primary composite outcome occurred in 16% of gAPP patients compared with 58% in gCONV (P < .010). Hypoglycemia incidence was lower in the gAPP (4% vs 16%, P = .046). The gAPP protocol also resulted in shorter hospital stays and reduced costs. CONCLUSIONS: The InsulinAPP protocol effectively optimizes GC and reduces adverse outcomes in T2DM patients' post-CABG surgery, offering a cost-effective solution for inpatient diabetes management.

Dissociating the metabolic and tumor-suppressive activity of p53.

The tumor suppressor p53 regulates metabolic homeostasis. Recently, Tsaousidou et al. reported that selective activation of p53 via downregulation of Tudor interacting repair regulator (TIRR) confers protection against cancer despite obesity and insulin resistance, providing new insights into the role of p53 at the intersection of oncogenesis and systemic metabolism.

Adipocyte endothelin B receptor activation inhibits adiponectin production and causes insulin resistance in obese mice.

AIMS: Endothelin-1 (ET-1) is elevated in patients with obesity and adipose tissue of obese mice fed high-fat diet (HFD); however, its contribution to the pathophysiology of obesity is not fully understood. Genetic loss of endothelin type B receptors (ETB) improves insulin sensitivity in rats and leads to increased circulating adiponectin, suggesting that ETB activation on adipocytes may contribute to obesity pathophysiology. We hypothesized that elevated ET-1 in obesity promotes insulin resistance by reducing the secretion of insulin sensitizing adipokines, via ETB receptor. METHODS: Male adipocyte-specific ETB receptor knockout (adETBKO), overexpression (adETBOX), or control littermates were fed either normal diet (NMD) or high-fat diet (HFD) for 8 weeks. RESULTS: RNA-sequencing of epididymal adipose (eWAT) indicated differential expression of over 5500 genes (p < 0.05) in HFD compared to NMD controls, and changes in 1077 of these genes were attenuated in HFD adETBKO mice. KEGG analysis indicated significant increase in metabolic signaling pathway. HFD adETBKO mice had significantly improved glucose and insulin tolerance compared to HFD control. In addition, adETBKO attenuated changes in plasma adiponectin, insulin, and leptin that is observed in HFD versus NMD control mice. Treatment of primary adipocytes with ET-1 caused a reduction in adiponectin production that was attenuated in cells pretreated with an ETB antagonist. CONCLUSION: These data indicate elevated ET-1 in adipose tissue of mice fed HFD inhibits adiponectin production and causes insulin resistance through activation of the ETB receptor on adipocytes.

Resistance exercise breaks during prolonged sitting augment the blood flow response to a subsequent oral glucose load in sedentary adults.

Sitting-induced impairments in postprandial blood flow are an important link between sedentary behaviour and cardiometabolic disease risk. The objective of this work was to examine the effects of resistance exercise breaks (REB) performed every 30 min during an otherwise sedentary 3-h period on the vasodilatory response to a subsequent oral glucose load in sedentary adults. Twenty-four sedentary adults (27 ± 7 years, 16 females) completed two conditions. Fasting blood glucose, insulin, popliteal artery blood flow (PABF) and gastrocnemius perfusion were measured immediately before standardized breakfast consumption. After breakfast, the 3-h REB or uninterrupted (SIT) intervention period commenced. Participants sat at a workstation, and popliteal artery shear rate (PASR) was measured 60 and 120 min into this period. In the REB condition, participants performed a 3-min REB (3 × [20 s squats, 20 s high knees, 20 s calf raises]) every 30 min. Following the intervention period, baseline measurements were repeated. Participants then consumed a 75 g glucose beverage, and PABF and perfusion were measured every 30-60 min for the following 120 min. Relative to SIT, REB increased PASR at 60 min (+31.4 ± 9.2/s, P = 0.037) and 120 min (+37.4 ± 10.2/s, P = 0.019) into the intervention period. Insulin and glucose increased (P < 0.001) in response to glucose consumption, with no differences between conditions (P ≥ 0.299). In response to the glucose load, perfusion (1.57 vs. 1.11 mL/100 mL/min, P = 0.023) and PABF (+45.3 ± 11.8 mL/min, P = 0.001) were greater after REB versus SIT. Performing 3-min REB every 30 min during an otherwise sedentary 3-h period augmented leg blood flow responses to an oral glucose load. HIGHLIGHTS: What is the central question of this study? Can 3-min resistance exercise breaks (REB) performed during an otherwise sedentary 3-h period augment the vasodilatory response to a subsequent oral glucose load in sedentary adults? What is the main finding and its importance? Performing 3-min REB, which included squats, high knees, and calf raises, every 30 min augmented lower limb blood flow responses to a subsequent oral glucose load compared to 3 h of uninterrupted sitting in sedentary adults. Sitting-induced impairment in postprandial vasodilatory function has been identified as a link between sedentary behaviour and cardiometabolic disease. Thus, the current study presents a potentially effective strategy to offset this risk.

Insulin sensitivity, disposition index and insulin clearance in cystic fibrosis: a cross-sectional study.

AIMS/HYPOTHESIS: The aim of this study was to investigate insulin secretion, insulin sensitivity, disposition index and insulin clearance by glucose tolerance status in individuals with cystic fibrosis (CF) and exocrine pancreatic insufficiency. METHODS: In a cross-sectional study, we conducted an extended (ten samples) OGTT in individuals with pancreatic-insufficient CF (PI-CF). Participants were divided into normal glucose tolerance (NGT), early glucose intolerance (EGI), impaired glucose tolerance (IGT) and CF-related diabetes (CFRD) groups. We used three different oral minimal models to assess insulin secretion, insulin sensitivity and insulin clearance during the OGTT. We evaluated insulin secretion using total secretion (Φ total), first-phase secretion (Φ dynamic) and second-phase secretion (Φ static) from the model, and we estimated the disposition index by multiplying Φ total and insulin sensitivity. RESULTS: Among 61 participants (NGT 21%, EGI 33%, IGT 16%, CFRD 30%), insulin secretion indices (Φ total, dynamic and static) were significantly lower in the CFRD group compared with the other groups. Insulin sensitivity declined with worsening in glucose tolerance (p value for trend <0.001) and the disposition index declined between NGT and EGI and between IGT and CFRD. Those with CFRD had elevated insulin clearance compared with NGT (p=0.019) and low insulin secretion (Φ total) was also associated with high insulin clearance (p<0.001). CONCLUSIONS/INTERPRETATION: In individuals with PI-CF, disposition index declined with incremental impairment in glucose tolerance due to a reduction in both insulin secretion and insulin sensitivity. Moreover in CF, reduced insulin secretion was associated with higher insulin clearance.

GDF15 is dispensable for the insulin-sensitizing effects of chronic exercise.

Growth and differentiation factor 15 (GDF15) has recently emerged as a weight loss and insulin-sensitizing factor. Growing evidence also supports a role for GDF15 as a physiological, exercise-induced stress signal. Here, we tested whether GDF15 is required for the insulin-sensitizing effects of exercise in mice and humans. At baseline, both under a standard nutritional state and high-fat feeding, GDF15 knockout (KO) mice display normal glucose tolerance, systemic insulin sensitivity, maximal speed, and endurance running capacity when compared to wild-type littermates independent of sex. When submitted to a 4-week exercise training program, both lean and obese wild-type and GDF15 KO mice similarly improve their endurance running capacity, glucose tolerance, systemic insulin sensitivity, and peripheral glucose uptake. Insulin-sensitizing effects of exercise training were also unrelated to changes in plasma GDF15 in humans. In summary, we here show that GDF15 is dispensable for the insulin-sensitizing effects of chronic exercise.

Dietary and circulating branched chain amino acids are unfavorably associated with body fat measures among Chinese adults.

Animal studies showed a detrimental effect of dietary branched chain amino acids (BCAAs) on metabolic health, while epidemiological evidence on dietary BCAAs and obesity is limited and inconclusive. We hypothesized that high dietary and circulating BCAAs are unfavorably associated with obesity in community-dwelling adults. We evaluated the 1-year longitudinal associations of dietary BCAA intake and circulating BCAAs with body fat measures. Body weight, height, and circumferences of the waist (WC) and hip (HC) were measured at baseline and again after 1-year. Body composition and liver fat [indicated by controlled attenuation parameter (CAP)] were also assessed after 1-year. Serum BCAA concentrations at baseline were quantified by liquid chromatography mass spectrometry. Diet was collected using 4 quarterly 3-day recalls during the 1-year. The correlation coefficients between dietary and serum BCAAs were 0.12 (P = .035) for total dietary BCAAs, and ranged from -0.02 (soy foods, P = .749) to 0.18 (poultry, P = .001). Total dietary BCAA intake was associated with increase in body weight (ß = 0.044, P = .022) and body mass index (BMI, ß = 0.047, P = .043). BCAAs from animal foods were associated with increase in HC, while BCAAs from soy foods were associated with weight gain and higher CAP (all P < .05). Serum BCAAs were associated with higher WC, HC, BMI, body fat mass, visceral fat level, and CAP (all P < .05). These results support that dietary and circulating BCAAs are positively associated with the risk of obesity. More cohort studies with validated dietary assessment tools and long-term follow-up among diverse populations are needed to confirm our findings.

Exploring effects of melatonin supplementation on insulin resistance: An updated systematic review of animal and human studies.

BACKGROUND: Insulin resistance (IR), defined as an impaired response to insulin stimulation of target tissues, is a substantial determinant of many metabolic disorders. This study aimed to update the findings of the previous systematic review evidence regarding the effect of melatonin on factors related to IR, including hyperinsulinemia, hyperglycemia, homeostasis model assessment of insulin resistance (HOMA-IR), and quantitative insulin sensitivity check index (QUICKI). METHODS: We systematically reviewed the evidence on the impact of melatonin supplementation on IR indices, fasting insulin, and fasting plasma glucose. PubMed, ScienceDirect, SCOPUS, and Google Scholar databases were searched until March 2024. RESULTS: We identified 6114 potentially relevant articles during the search. Eighteen animal studies and 15 randomized clinical trials met the inclusion criteria. The results indicated that melatonin supplementation reduced fasting plasma glucose (FPG, 14 out of 29 studies), fasting insulin (22 out of 28 studies), HOMA-IR (28 out of 33 studies), and increased QUICKI (7 out of 7 studies). According to RCT studies, melatonin treatment at a dosage of 10 mg reduced HOMA-IR levels in individuals with various health conditions. CONCLUSION: According to most evidence, melatonin supplementation may decrease fasting insulin and HOMA-IR and increase QUICKI but may not affect FPG.