Humans ; Incretins/therapeutic use* ; Diabetes Mellitus, Type 2/drug therapy* ; Hypoglycemic Agents/therapeutic use* ; Risk Assessment

Bone disease is a serious complication to diabetes. Patients with type 1 diabetes (T1D) and type 2 diabetes (T2D) suffer from an increased risk of fracture, most notably at the hip, compared with patients without diabetes. Confounders such as patient sex, age, body mass index, blood glucose status, fall risk, and diabetes medications may influence the fracture risk. Different underlying mechanisms contribute to bone disease in patients with diabetes. Bone quality is affected by low bone turnover in T1D and T2D, and furthermore, incorporation of advanced glycation end-products, changes in the incretin hormone response, and microvascular complications contribute to impaired bone quality and increased fracture risk. Diagnosis of bone disease in patients with diabetes is a challenge as current methods for fracture prediction such as bone mineral density T-score and fracture risk assessment tools underestimate fracture risk for patients with T1D and T2D. This review focuses on bone disease and fracture risk in patients with diabetes regarding epidemiology, underlying disease mechanisms, and diagnostic methods, and we also provide considerations regarding the management of diabetes patients with bone disease in terms of an intervention threshold and different treatments.
Blood Glucose ; Body Mass Index ; Bone Density ; Bone Diseases ; Bone Remodeling ; Diagnosis ; Epidemiology ; Hip ; Humans ; Incretins ; Osteoporosis ; Risk Assessment

BACKGROUND: We performed this study to identify factors related to intact incretin levels in patients with type 2 diabetes mellitus (T2DM). METHODS: We cross-sectionally analyzed 336 patients with T2DM. Intact glucagon-like peptide 1 (iGLP-1) and intact glucose-dependent insulinotropic polypeptide (iGIP) levels were measured in a fasted state and 30 minutes after ingestion of a standard mixed meal. The differences between 30 and 0 minute iGLP-1 and iGIP levels were indicated as ΔiGLP-1 and ΔiGIP. RESULTS: In simple correlation analyses, fasting iGLP-1 was positively correlated with glucose, C-peptide, creatinine, and triglyceride levels, and negatively correlated with estimated glomerular filtration rate. ΔiGLP-1 was positively correlated only with ΔC-peptide levels. Fasting iGIP showed positive correlations with glycosylated hemoglobin (HbA1c) and fasting glucose levels, and negative correlations with ΔC-peptide levels. ΔiGIP was negatively correlated with diabetes duration and HbA1c levels, and positively correlated with Δglucose and ΔC-peptide levels. In multivariate analyses adjusting for age, sex, and covariates, fasting iGLP-1 levels were significantly related to fasting glucose levels, ΔiGLP-1 levels were positively related to ΔC-peptide levels, fasting iGIP levels were related to fasting C-peptide levels, and ΔiGIP levels were positively related to ΔC-peptide and Δglucose levels. CONCLUSION: Taken together, intact incretin levels are primarily related to C-peptide and glucose levels. This result suggests that glycemia and insulin secretion are the main factors associated with intact incretin levels in T2DM patients.
C-Peptide ; Creatinine ; Diabetes Mellitus, Type 2 ; Eating ; Fasting ; Gastric Inhibitory Polypeptide ; Glomerular Filtration Rate ; Glucagon-Like Peptide 1 ; Glucose ; Hemoglobin A, Glycosylated ; Humans ; Incretins ; Insulin ; Meals ; Multivariate Analysis ; Triglycerides

BACKGROUND: Metformin, sulfonylurea, and dietary fiber are known to affect gut microbiota in patients with type 2 diabetes mellitus (T2DM). This open and single-arm pilot trial investigated the effects of the additional use of fiber on glycemic parameters, insulin, incretins, and microbiota in patients with T2DM who had been treated with metformin and sulfonylurea. METHODS: Participants took fiber for 4 weeks and stopped for the next 4 weeks. Glycemic parameters, insulin, incretins during mixed-meal tolerance test (MMTT), lipopolysaccharide (LPS) level, and fecal microbiota were analyzed at weeks 0, 4, and 8. The first tertile of difference in glucose area under the curve during MMTT between weeks 0 and 4 was defined as ‘responders’ and the third as ‘nonresponders,’ respectively. RESULTS: In all 10 participants, the peak incretin levels during MMTT were higher and LPS were lower at week 4 as compared with at baseline. While the insulin sensitivity of the ‘responders’ increased at week 4, that of the ‘nonresponders’ showed opposite results. However, the results were not statistically significant. In all participants, metabolically unfavorable microbiota decreased at week 4 and were restored at week 8. At baseline, metabolically hostile bacteria were more abundant in the ‘nonresponders.’ In ‘responders,’ Roseburia intestinalis increased at week 4. CONCLUSION: While dietary fiber did not induce additional changes in glycemic parameters, it showed a trend of improvement in insulin sensitivity in ‘responders.’ Even if patients are already receiving diabetes treatment, the additional administration of fiber can lead to additional benefits in the treatment of diabetes.
Bacteria ; Diabetes Mellitus, Type 2 ; Dietary Fiber ; Gastrointestinal Microbiome ; Glucose ; Humans ; Incretins ; Insulin ; Insulin Resistance ; Metformin ; Microbiota ; Sulfonylurea Compounds

BACKGROUND: Based on reported results of three large cardiovascular outcome trials (CVOTs) of glucagon-like peptide 1 receptor agonists (GLP-1 RAs), we aimed to investigate the overall effect of GLP-1 RAs on major adverse cardiovascular events (MACEs) and to identify subpopulations exhibiting the greatest cardiovascular (CV) benefit. METHODS: Three CVOTs reporting effects of long-acting GLP-1 RAs were included: LEADER (liraglutide), SUSTAIN-6 (semaglutide), and EXSCEL (exenatide once weekly). In all studies, the primary endpoint was three-point MACE, comprising CV death, non-fatal myocardial infarction, and non-fatal stroke. Overall effect estimates were calculated as hazard ratios and 95% confidence intervals (CIs) using the random-effects model; subgroup analyses reported in the original studies were similarly analyzed. RESULTS: Overall, statistically significant risk reductions in MACE and CV death were observed. Subgroup analysis indicated a significant racial difference with respect to CV benefit (P for interaction <0.001), and more substantial risk reductions were observed in subjects of African origin (relative risk [RR], 0.78; 95% CI, 0.60 to 0.99) and in Asians (RR, 0.35; 95% CI, 0.09 to 1.32). However, post hoc analysis (Bonferroni method) revealed that only Asians exhibited a significantly greater CV benefit from treatment, compared with white subjects (P<0.0001). CONCLUSION: Long-acting GLP-1 RAs reduced risks of MACE and CV deaths in high-risk patients with type 2 diabetes mellitus. Our findings of a particularly effective reduction in CV events with GLP-1 RA in Asian populations merits further exploration and dedicated trials in specific populations.
Asian Continental Ancestry Group ; Cardiovascular Diseases ; Diabetes Mellitus, Type 2 ; Glucagon-Like Peptide 1 ; Humans ; Incretins ; Myocardial Infarction ; Stroke

The increasing risk of glucose intolerance and diabetes associated with aging is well established. However, it is difficult to determine whether changes in glucose metabolism result from biological aging itself or due to various environmental factors that occur during the aging process. Many epidemiologic studies have shown that plasma glucose levels after oral glucose tolerance test rise consecutively for every decade of age, but many of these studies also demonstrated the effects of environmental factors including obesity and exercise. In some studies, the development of insulin resistance and insulin secretion defects due to biological aging itself have also been identified as major etiologic factors of glucose intolerance. However, the rate of diabetes development due to these factors is expected to be very slow and largely preventable by addressing environmental risk factors.
Aging ; Blood Glucose ; Carbohydrate Metabolism ; Epidemiologic Studies ; Glucose Intolerance ; Glucose Tolerance Test ; Glucose ; Incretins ; Insulin ; Insulin Resistance ; Metabolism ; Obesity ; Risk Factors

Postprandial hyperglycemia is associated with the risk of diabetes mellitus, cardiovascular disease, and mortality. Nutrition therapy is an important component of the management of postprandial hyperglycemia. Postprandial glucose levels are determined by several factors, such as the quantity and composition of nutrients, gastric emptying rates, secretion of incretin hormones, insulin secretion, glucose uptake by peripheral tissues, and endogenous glucose production. Nutrient preload and food order (or meal sequence) are dietary approaches targeting these factors. Nutrient preload reduces postprandial glucose excursion by enhancing insulin secretion, augmenting the secretion of glucagonlike peptide-1, and delaying gastric emptying. Carbohydrates-last food order improves glycemic control, increases the secretion of glucagon-like peptide-1, and decreases insulin requirements. Therefore, both nutrient preload and manipulation of food order can be an effective, safe, and feasible strategy for treating hyperglycemia in individuals with diabetes mellitus.
Carbohydrates ; Cardiovascular Diseases ; Diabetes Mellitus ; Gastric Emptying ; Gastrointestinal Hormones ; Glucagon-Like Peptide 1 ; Glucose* ; Hyperglycemia ; Incretins ; Insulin* ; Meals ; Mortality ; Nutrition Therapy ; Whey Proteins

Nonalcoholic fatty liver disease (NAFLD) is more prevalent in diabetic patients than in non-diabetic subjects, because the two diseases share a common pathophysiological mechanism. Associated abnormalities can be observed from the pre-diabetic stage. Lifestyle intervention, including diet, exercise, and weight loss, is the primary recommended therapy for NAFLD. Among the therapeutic drugs for NAFLD treatment, anti-diabetic agents are aimed at improving or slowing the progression of NAFLD in addition to lowering blood glucose. In this paper, we systemically review the evidence surrounding antidiabetic medications and their ability to improve disease progression in patients with NAFLD.
Blood Glucose ; Diabetes Mellitus ; Diet ; Disease Progression ; Humans ; Incretins ; Life Style ; Non-alcoholic Fatty Liver Disease* ; Sodium-Glucose Transporter 2 ; Thiazolidinediones ; Weight Loss

Dipeptidyl peptidase4 (DPP4) inhibitors such as gemigliptin are anti-diabetic drugs elevating plasma concentration of incretins such as GLP-1. In addition to the DPP4 inhibition, gemigliptin might directly improve the functions of vessels under pathological conditions. To test this hypothesis, we investigated whether the acetylcholine-induced endothelium dependent relaxation (ACh-EDR) of mesenteric arteries (MA) are altered by gemigliptin pretreatment in Spontaneous Hypertensive Rats (SHR) and in Wistar-Kyoto rats (WKY) under hyperglycemia-like conditions (HG; 2 hr incubation with 50 mM glucose). ACh-EDR of WKY was reduced by the HG condition, which was significantly recovered by 1 µM gemigliptin while not by saxagliptin and sitagliptin up to 10 µM. The ACh-EDR of SHR MA was also improved by 1 µM gemigliptin while similar recovery was observed with higher concentration (10 µM) of saxagliptin and sitagliptin. The facilitation of ACh-EDR by gemigliptin in SHR was not observed under pretreatment with NOS inhibitor, L-NAME. In the endotheliumdenuded MA of SHR, sodium nitroprusside induced dose-dependent relaxation was not affected by gemigliptin. The ACh-EDR in WKY was decreased by treatment with 30 µM pyrogallol, a superoxide generator, which was not prevented by gemigliptin. Exendin-4, a GLP-1 analogue, could not enhance the ACh-EDR in SHR MA. The present results of ex vivo study suggest that gemigliptin enhances the NOS-mediated EDR of the HG-treated MA as well as the MA from SHR via GLP-1 receptor independent mechanism.
Animals ; Endothelium ; Glucagon-Like Peptide 1 ; Glucagon-Like Peptide-1 Receptor ; Hyperglycemia ; Hypertension ; Incretins ; Mesenteric Arteries* ; NG-Nitroarginine Methyl Ester ; Nitroprusside ; Plasma ; Pyrogallol ; Rats ; Rats, Inbred SHR* ; Relaxation ; Sitagliptin Phosphate ; Superoxides ; Vasodilation*

In 2008, the United States Food and Drug Administration issued guidance which mandated long-term cardiovascular outcome trials (CVOTs) to assess the safety of new antidiabetic drugs for type 2 diabetes. Since 2008, three CVOTs that have studied dipeptidyl peptidase-4 (DPP-4) inhibitors and four CVOTs of a glucagon-like peptide-1 (GLP-1) receptor agonist (GLP-1RA) have been reported. Each of the completed CVOTs showed the noninferiority of respective drugs to placebo for primary CV composite endpoint. Among them, liraglutide and semaglutide showed a reduction of major adverse cardiovascular events. However, the mechanisms for the observed cardiovascular differences between DPP-4 inhibitors and GLP-1RA, and across individual GLP-1RA are not clearly understood. Therefore, this review will summarize the CVOTs of the DPP-4 inhibitors and GLP-1RA, interpretation of cardioprotective results of incretin-based therapy and the possible mechanism of action.
Diabetes Mellitus, Type 2 ; Dipeptidyl-Peptidase IV Inhibitors ; Glucagon-Like Peptide 1 ; Hypoglycemic Agents ; Incretins* ; Liraglutide ; United States Food and Drug Administration