Effects of progressive resistance training in individuals with type 2 diabetic polyneuropathy: a randomised assessor-blinded controlled trial.

AIMS/HYPOTHESIS: The aim of this study was to evaluate the effects of progressive resistance training (PRT) on muscle strength, intraepidermal nerve fibre density (IENFD) and motor function in individuals with type 2 diabetic polyneuropathy (DPN) and to compare potential adaptations to those of individuals with type 2 diabetes without DPN and healthy controls. METHODS: This was an assessor-blinded trial conducted at the Neurology department, Aarhus University Hospital. Adults with type 2 diabetes, with and without DPN and healthy control participants were randomised to either supervised PRT or non-PRT for 12 weeks. Allocation was concealed by a central office unrelated to the study. The co-primary outcomes were muscle strength in terms of the peak torque of the knee and ankle extensors and flexors, and IENFD. Secondary outcome measures included the 6 min walk test (6MWT), five-time sit-to-stand test (FTSST) and postural stability index obtained by static posturography. RESULTS: A total of 109 individuals were enrolled in three groups (type 2 diabetes with DPN [n = 42], type 2 diabetes without DPN [n = 32] and healthy control [n = 35]). PRT resulted in muscle strength gains of the knee extensors and flexors in all three groups using comparative analysis (DPN group, PRT 10.3 ± 9.6 Nm vs non-PRT -0.4 ± 8.2 Nm; non-DPN group, PRT 7.5 ± 5.8 Nm vs non-PRT 0.6 ± 8.8 Nm; healthy control group, PRT 6.3 ± 9.0 Nm vs non-PRT -0.4 ± 8.4 Nm; p<0.05, respectively). Following PRT the DPN group improved the 6MWT (PRT 34.6 ± 40.9 m vs non-PRT 2.7 ± 19.6 m; p=0.001) and the FTSST (PRT -1.5 ± 2.2 s vs non-PRT 1.5 ± 4.6 s; p=0.02). There was no change in IENFD following PRT in any of the groups. CONCLUSIONS/INTERPRETATION: PRT improved muscle strength of the knee extensors and flexors and motor function in individuals with type 2 diabetic polyneuropathy at levels comparable with those seen in individuals with diabetes without DPN and healthy control individuals, while no effects were observed in IENFD. TRIAL REGISTRATION: ClinicalTrials.gov NCT03252132 FUNDING: Research reported in this paper is part of the International Diabetic Neuropathy Consortium (IDNC) research programme, supported by a Novo Nordisk Foundation Challenge Program grant (grant no. NNF14OC0011633) and Aarhus University.

Alignment of rendered images with photographs for testing appearance models.

We propose a method for direct comparison of rendered images with a corresponding photograph in order to analyze the optical properties of physical objects and test the appropriateness of appearance models. To this end, we provide a practical method for aligning a known object and a point-like light source with the configuration observed in a photograph. Our method is based on projective transformation of object edges and silhouette matching in the image plane. To improve the similarity between rendered and photographed objects, we introduce models for spatially varying roughness and a model where the distribution of light transmitted by a rough surface influences direction-dependent subsurface scattering. Our goal is to support development toward progressive refinement of appearance models through quantitative validation.

Effects of Different Fasting Durations on Glucose and Lipid Metabolism in Sprague Dawley Rats.

Overnight fasting of varying length is common practice when studying glucose and lipid metabolism in rats. However, prolonged fasting may influence insulin sensitivity, and it is unknown to which extent different fasting durations affect postprandial metabolism in rats. The purpose of this study was to investigate the effect of different fasting durations (6-, 12-, or 18-h) on fat tolerance and glucose tolerance in male Sprague Dawley rats. We also aimed to examine the effect of two test fats with different fatty acid composition on postprandial triglycerides. We conducted a fat tolerance test, where butterfat or rapeseed oil was administered in a crossover design (experiment 1), and an oral glucose tolerance test (experiment 2). Regarding the fat tolerance test, we found no effects of fasting duration on triglycerides or free fatty acids, whereas the 18-h fast resulted in reduced glucose and insulin area under the curves. We did not find differential effects of butterfat and rapeseed oil on the outcomes. We found decreased fasting insulin and homeostasis model assessment of insulin resistance (HOMA-IR), and increased beta-hydroxybutyric acid concentrations after 18-h fast compared with shorter fasting durations. Regarding the oral glucose tolerance test, both 12-h and 18-h fast resulted in greater peak insulin concentrations than 6-h fast, and peak glucose concentrations were higher after 18-h than 12-h fast. We found no effects of fasting on the insulin sensitivity index. In conclusion, extending the fasting duration had an impact on glucose metabolism in rats, but did not appear to influence fat tolerance.

Effects of a diet rich in arabinoxylan and resistant starch compared with a diet rich in refined carbohydrates on postprandial metabolism and features of the metabolic syndrome.

PURPOSE: Low intake of dietary fibre is associated with the development of type 2 diabetes. Dyslipidaemia plays a key role in the pathogenesis of type 2 diabetes. Knowledge of the impact of dietary fibres on postprandial lipaemia is, however, sparse. This study aimed in subjects with metabolic syndrome to assess the impact on postprandial lipaemia and features of the metabolic syndrome of a healthy carbohydrate diet (HCD) rich in cereal fibre, arabinoxylan and resistant starch compared to a refined-carbohydrate western-style diet (WSD). METHODS: Nineteen subjects completed the randomised, crossover study with HCD and WCD for 4-week. Postprandial metabolism was evaluated by a meal-challenge test and insulin sensitivity was assessed by HOMA-IR and Matsuda index. Furthermore, fasting cholesterols, serum-fructosamine, circulating inflammatory markers, ambulatory blood pressure and intrahepatic lipid content were measured. RESULTS: We found no diet effects on postprandial lipaemia. However, there was a significant diet × statin interaction on total cholesterol (P = 0.02) and LDL cholesterol (P = 0.002). HCD decreased total cholesterol (-0.72 mmol/l, 95% CI (-1.29; -0.14) P = 0.03) and LDL cholesterol (-0.61 mmol/l, 95% CI (-0.86; -0.36) P = 0.002) compared with WSD in subjects on but not without statin treatment. We detected no other significant diet effects. CONCLUSIONS: In subjects with metabolic syndrome on statins a 4-week diet rich in arabinoxylan and resistant starch improved fasting LDL and total cholesterol compared to subjects not being on statins. However, we observed no diet related impact on postprandial lipaemia or features of the metabolic syndrome. The dietary fibre x statin interaction deserves further elucidation.

In vivo measurement and biological characterisation of the diabetes-associated mutant insulin p.R46Q (GlnB22-insulin).

AIMS/HYPOTHESIS: Heterozygous mutations in the insulin gene that affect proinsulin biosynthesis and folding are associated with a spectrum of diabetes phenotypes, from permanent neonatal diabetes to MODY. In vivo studies of these mutations may lead to a better understanding of insulin mutation-associated diabetes and point to the best treatment strategy. We studied an 18-year-old woman with MODY heterozygous for the insulin mutation p.R46Q (GlnB22-insulin), measuring the secretion of mutant and wild-type insulin by LC-MS. The clinical study was combined with in vitro studies of the synthesis and secretion of p.R46Q-insulin in rat INS-1 insulinoma cells. METHODS: We performed a standard 75 g OGTT in the 18-year-old woman and measured plasma glucose and serum insulin (wild-type insulin and GlnB22-insulin), C-peptide, proinsulin, glucagon and amylin. The affinity of GlnB22-insulin was tested on human insulin receptors expressed in baby hamster kidney (BHK) cells. We also examined the subcellular localisation, secretion and impact on cellular stress markers of p.R46Q-insulin in INS-1 cells. RESULTS: Plasma GlnB22-insulin concentrations were 1.5 times higher than wild-type insulin at all time points during the OGTT. The insulin-receptor affinity of GlnB22-insulin was 57% of that of wild-type insulin. Expression of p.R46Q-insulin in INS-1 cells was associated with decreased insulin secretion, but not induction of endoplasmic reticulum stress. CONCLUSIONS/INTERPRETATION: The results show that beta cells can process and secrete GlnB22-insulin both in vivo and in vitro. Our combined approach of immunoprecipitation and LC-MS to measure mutant and wild-type insulin may be useful for the study of other mutant insulin proteins. The ability to process and secrete a mutant protein may predict a more benign course of insulin mutation-related diabetes. Diabetes develops when the beta cell is stressed because of increased demand for insulin, as observed in individuals with other insulin mutations that affect the processing of proinsulin to insulin or mutations that reduce the affinity for the insulin receptor.

Cafestol, a Bioactive Substance in Coffee, Has Antidiabetic Properties in KKAy Mice.

Daily coffee consumption is inversely associated with risk of type-2 diabetes (T2D). Cafestol, a bioactive substance in coffee, increases glucose-stimulated insulin secretion in vitro and increases glucose uptake in human skeletal muscle cells. We hypothesized that cafestol can postpone development of T2D in KKAy mice. Forty-seven male KKAy mice were randomized to consume chow supplemented daily with either 1.1 (high), 0.4 (low), or 0 (control) mg of cafestol for 10 weeks. We collected blood samples for fasting glucose, glucagon, and insulin as well as liver, muscle, and fat tissues for gene expression analysis. We isolated islets of Langerhans and measured insulin secretory capacity. After 10 weeks of intervention, fasting plasma glucose was 28-30% lower in cafestol groups compared with the control group (p < 0.01). Fasting glucagon was 20% lower and insulin sensitivity improved by 42% in the high-cafestol group (p < 0.05). Cafestol increased insulin secretion from isolated islets by 75-87% compared to the control group (p < 0.001). Our results show that cafestol possesses antidiabetic properties in KKAy mice. Consequently, cafestol may contribute to the reduced risk of developing T2D in coffee consumers and has a potential role as an antidiabetic drug.

Cafestol, a Bioactive Substance in Coffee, Stimulates Insulin Secretion and Increases Glucose Uptake in Muscle Cells: Studies in Vitro.

Diet and exercise intervention can delay or prevent development of type-2-diabetes (T2D), and high habitual coffee consumption is associated with reduced risk of developing T2D. This study aimed to test whether selected bioactive substances in coffee acutely and/or chronically increase insulin secretion from ß-cells and improve insulin sensitivity in skeletal muscle cells. Insulin secretion from INS-1E rat insulinoma cells was measured after acute (1-h) and long-term (72-h) incubation with bioactive substances from coffee. Additionally, we measured uptake of radioactive glucose in human skeletal muscle cells (SkMC) after incubation with cafestol. Cafestol at 10(-8) and 10(-6) M acutely increased insulin secretion by 12% (p < 0.05) and 16% (p < 0.001), respectively. Long-term exposure to 10(-10) and 10(-8) M cafestol increased insulin secretion by 34% (p < 0.001) and 68% (p < 0.001), respectively. Caffeic acid also increased insulin secretion acutely and chronically. Chlorogenic acid, trigonelline, oxokahweol, and secoisolariciresinol did not significantly alter insulin secretion acutely. Glucose uptake in SkMC was significantly enhanced by 8% (p < 0.001) in the presence of 10(-8) M cafestol. This newly demonstrated dual action of cafestol suggests that cafestol may contribute to the preventive effects on T2D in coffee drinkers and be of therapeutic interest.

Novel Approach for Treating Diabetes in a Patient With the Heterozygous Pathogenic Variant R46Q in the Insulin Gene.

Maturity-onset diabetes of the young (MODY) is a monogenic disorder of glucose homeostasis with several subtypes, each defined by a distinct genetic etiology. Heterozygous pathogenic variants in the insulin gene are rare causes of MODY, and optimal treatment strategies remain uncertain. Herein we describe a patient with diabetes caused by the heterozygous pathogenic variant R46Q in the insulin gene and the glycemic response to selected antidiabetic treatment regimens. The R46Q pathogenic variant leads to secretion of both mutant and wild-type insulin. In vitro, the mutant insulin is associated with a lower insulin-receptor affinity compared with wild-type insulin and a decline in wild-type insulin secretion. In our patient, treatment with a combination of long- and short-acting insulin led to a decline in hemoglobin A1C (HbA1c), although not to the recommended target. A shift to metformin and subsequent add-on of a sodium-glucose cotransporter 2 inhibitor (SGLT2i) resulted in HbA1c levels of less than 7% (53 mmol/mol) and durable glycemic control. Continuous glucose monitoring and oral glucose tolerance tests confirmed that treatment with metformin and SGLT2i was superior to treatment with insulin. In conclusion, diabetes caused by the pathogenic variant R46Q in the insulin gene may be effectively treated with noninsulin.

Beneficial glycaemic effects of high-amylose barley bread compared to wheat bread in type 2 diabetes.

BACKGROUND: Cereals foods with a high content of dietary fibres or amylose have potential to lower postprandial glucose levels. Optimisation of cereal foods may improve management of type 2 diabetes (T2D). METHODS: We investigated the impact on 4 h postprandial glucose responses given as incremental area under curve (iAUC) of bread made of either 50% RNAi-based (genetically modified) amylose-only barley flour (AmOn) (and 50% wheat flour), 50% hulless barley flour (and 50% wheat flour) or 75% hulless barley (and 25% wheat flour) in subjects with T2D compared with 100% wheat flour bread. DESIGN: Twenty adults with T2D were randomly allocated to one of four breads at four separate visits. We measured fasting and 4 h postprandial responses of glucose, insulin, glucagon, triacylglycerol (TG), free fatty acids (FFA), glucagon-like peptide-1 (GLP-1) and gastric inhibitory polypeptide (GIP). Mixed model ANOVA was used to examine the differences. RESULTS: Bread made from 50% AmOn lowered the 4 h postprandial glucose by 34%, 27%, 23% (P < 0.05) compared with 100% wheat, 50% or 75% hulless barley, respectively. Bread made from 75% hulless barley reduced the postprandial glucose response (iAUC) by 11% (P < 0.05) compared to 100% wheat bread. Postprandial insulin responses (iAUC) were reduced for 50% AmOn compared with 100% wheat and 50% hulless barley and for 75% hulless compared to 50% hulless barley bread (P < 0.05). 4 h postprandial glucagon (tAUC) did not differ between the four bread types (P > 0.05). Lower postprandial GIP (iAUC) was observed after all barley breads compared to 100% wheat (P < 0.05), whereas no difference was seen in postprandial GLP-1. Postprandial TG and FFA (tAUC) were difficult to judge due to differences in fasting values. CONCLUSIONS: Bread made by replacing wheat flour with either 50% high-amylose or 75% hulless barley flour lowered postprandial glucose responses compared to 100% wheat bread indicating a beneficial impact on glucose regulation in T2D subjects. This trial was registered at clinicaltrials.gov as NCT04646746.

Serum osteoglycin is stable during various glycemic challenges in healthy men.

PURPOSE: Osteoglycin is hypothesized to be metabolically active and may enhance insulin action. We hypothesized that osteoglycin levels increase during hyperglycemia as a physiological response to enhance the effects of insulin. METHODS: Eight healthy males were included in a cross-over study consisting of three study days following an 8 h fast. First, we performed an oral glucose tolerance test (OGTT); second, an isoglycemic intravenous glucose infusion (IIGI); and third, a control period consisting of a three hour fast. We analyzed blood samples for circulating osteoglycin levels during the study days. Repeated measures ANOVA was performed to compare levels of s-osteoglycin between OGTT, IIGI, and the fasting control. RESULTS: There were no differences in baseline osteoglycin levels among study days (p > 0.05). We observed no significant changes neither in absolute s-osteoglycin levels by time (p = 0.14) nor over time by study day (p = 0.99). Likewise, we observed no significant changes in percentage s-osteoglycin levels neither by time (p = 0.11) nor over time by study day (p = 0.89). CONCLUSION: We found that s-osteoglycin levels were stable for three hours during OGTT, IIGI, and fasting in healthy males. Based on the present study, circulating s-osteoglycin levels may be measured independently of fasting or non-fasting conditions. Furthermore, circulating physiological levels of glucose and insulin did not affect s-osteoglycin levels.

Effect of fruit restriction on glycemic control in patients with type 2 diabetes--a randomized trial.

BACKGROUND: Medical nutrition therapy is recognized as an important treatment option in type 2 diabetes. Most guidelines recommend eating a diet with a high intake of fiber-rich food including fruit. This is based on the many positive effects of fruit on human health. However some health professionals have concerns that fruit intake has a negative impact on glycemic control and therefore recommend restricting the fruit intake. We found no studies addressing this important clinical question. The objective was to investigate whether an advice to reduce the intake of fruit to patients with type 2 diabetes affects HbA1c, bodyweight, waist circumference and fruit intake. METHODS: This was an open randomized controlled trial with two parallel groups. The primary outcome was a change in HbA1c during 12 weeks of intervention. Participants were randomized to one of two interventions; medical nutrition therapy + advice to consume at least two pieces of fruit a day (high-fruit) or medical nutrition therapy + advice to consume no more than two pieces of fruit a day (low-fruit). All participants had two consultations with a registered dietitian. Fruit intake was self-reported using 3-day fruit records and dietary recalls. All assessments were made by the "intention to treat" principle. RESULTS: The study population consisted of 63 men and women with newly diagnosed type 2 diabetes. All patients completed the trial. The high-fruit group increased fruit intake with 125 grams (CI 95%; 78 to 172) and the low-fruit group reduced intake with 51 grams (CI 95%; -18 to -83). HbA1c decreased in both groups with no difference between the groups (diff.: 0.19%, CI 95%; -0.23 to 0.62). Both groups reduced body weight and waist circumference, however there was no difference between the groups. CONCLUSIONS: A recommendation to reduce fruit intake as part of standard medical nutrition therapy in overweight patients with newly diagnosed type 2 diabetes resulted in eating less fruit. It had however no effect on HbA1c, weight loss or waist circumference. We recommend that the intake of fruit should not be restricted in patients with type 2 diabetes. TRIAL REGISTRATION: http://www.clinicaltrials.gov; Identifier: NCT01010594.

Aronia in the Type 2 Diabetes Treatment Regimen.

Aronia melanocarpa berries are rich in antioxidants and possess a high antioxidant capacity. Aronia berries have shown potential in type 2 diabetes mellitus (T2DM) treatment, and previous studies indicate improvements in glycemia after supplementation. Unfortunately, the effectiveness of aronia berries is limited by the low bioavailability of aronia, which fermentation could potentially overcome. The objective of this study was to compare the effects of fermented or non-fermented aronia pulp with placebo in subjects with T2DM. This study was a triple-blinded, triple-crossover study with eight-week intervention periods with fermented aronia extract (FAE), non-fermented aronia extract (AE), and placebo. Extracts were incorporated in snack bars with 37% aronia (FAE or AE) or wheat bran (placebo) and 63% raisins and coconut oil. Pre- and post-treatment period, we did fasting blood samples, including hemoglobin A1c, fructosamine, insulin, glucose, glucagon-like peptide-1, glucose-dependent insulinotropic peptide (GIP) and glucagon, oral glucose tolerance tests, and anthropometric measurements. Of 36 randomized participants, 23 completed the trial. Aside from a higher increase in GIP after FAE supplementation compared to after placebo supplementation, aronia extracts had no effect. The increase in GIP levels after FAE supplementation may hold potential benefits, but the overall clinical impact remains unclear.

The Impact of an 8-Week Supplementation with Fermented and Non-Fermented Aronia Berry Pulp on Cardiovascular Risk Factors in Individuals with Type 2 Diabetes.

Aronia berries contain antioxidants that may be health-promoting, e.g., demonstrated positive effects on hypertension and dyslipidaemia. There is a close link between cardiovascular diseases and hypertension and dyslipidaemia, and cardiovascular events are the leading cause of death among subjects with type 2 diabetes (T2D). Thus, we investigated the effect of an 8-week supplementation with fermented aronia extract (FAE), non-fermented aronia extract (AE), and placebo on cardiovascular risk factors. Snack bars were produced containing 34 g (37%) aronia extract, or 17 g (21%) wheat bran for placebo, as well as raisins and coconut oil. The study was randomized and blinded with a triple-crossover design. We examined the effects of aronia extracts on blood pressure, adiponectin, and high-sensitive C-reactive protein, and found no effects. After supplementation with placebo, there were significantly higher blood concentrations of total cholesterol, LDL-cholesterol, and HDL-cholesterol, with the placebo group showing significantly higher increases in total cholesterol and LDL-cholesterol than the AE group. Furthermore, we observed an increase in HDL-cholesterol in the FAE group and an increase in triglyceride in the AE group. Thus, we assume that the raisins may have increased the participants' cholesterol levels, with both AE and FAE having the potential to prevent this increase.

Effects of Chokeberries (Aronia spp.) on Cytoprotective and Cardiometabolic Markers and Semen Quality in 109 Mildly Hypercholesterolemic Danish Men: A Prospective, Double-Blinded, Randomized, Crossover Trial.

Background: Chokeberries (Aronia spp.) are known to exhibit both direct and indirect antioxidant properties and have been associated with beneficial effects on human health, including cardiovascular risk factors (inflammation, serum lipids, sugars, blood pressure), oxidative stress, and semen quality. This prospective, double-blinded, randomized, crossover clinical trial was conducted to elucidate the effects of Aronia supplementation on these health targets in mildly hypercholesterolemic men. Methods: The standardized Aronia supplementation comprised three wild Aronia spp. (A. arbutifolia, A prunifolia and A. melanocarpa) and the Aronia hybrid × Sorbaronia mitschurinii (standardized to 150 mg anthocyanins daily). Participants (n = 109) were healthy men with respect to all outcome targets except for the total cholesterol level (5.0−7.0 mM). Participants were randomized to supplementation with either Aronia or placebo for 90 days, followed by a wash-out period and lastly the complementary supplementation. Effects on the health parameters were compared among both the whole group of men and in subgroups according to age, body mass index (BMI), lifestyle, dietary habits, and serum glutathione levels at baseline. The study is registered in ClinicalTrials.gov.: NCT03405753. Results: Glutathione levels were significantly improved after 90 days intake of Aronia supplementation compared to placebo in the subgroup of men with a low level of glutathione at baseline (p = 0.038) and a high coffee intake (p = 0.045). A significant decrease in levels of sperm DNA fragmentation and an increase in the percentage of motile sperm were observed in men aged >40 and in men with BMI > 25. Further, these parameters were significantly improved in the dietary subgroup defined by a high level of coffee intake. Total cholesterol and low-density lipoprotein-cholesterol levels decreased significantly in men <40 years after Aronia supplementation. No statistically significant effects were observed regarding blood pressure, markers of blood sugar regulation, hemoglobin A1c, superoxide dismutase, catalase, isoprostane levels, high sensitivity C reactive protein, or other semen parameters. Conclusions: This study demonstrated a significant increase in glutathione levels and improvement of cytoprotective targets following Aronia supplementation in specific subgroups of men >40 years of age and BMI > 25 but did not demonstrate a significant effect in the overall analysis. The observed concurrent increase in glutathione levels and improvement of cytoprotective targets following Aronia supplementation in subgroups of men, suggests that the endogenous phase II antioxidant glutathione is involved in the modulation of the observed cytoprotective effects. This study is a good foundation for further investigation of these cytoprotective effects in groups with oxidative stress in a dose−response study.

Effects of Aronia melanocarpa on Cardiometabolic Diseases: A Systematic Review of Quasi-Design Studies and Randomized Controlled Trials.

OBJECTIVES: Aronia melanocarpa (Aronia) is a shrub with small berries, chokeberries. Chokeberries are claimed to possess health benefits due to a high content of polyphenols. Aronia is known to be extremely antioxidant; however, evidence for its health benefits is not established. This review gives an overview of the impact of Aronia on cardiometabolic risk factors and diseases. METHODS: Seventeen studies on cardiometabolic risk factors and diseases were identified through a systematic search on PubMed, Embase, and Cochrane. Inclusion criteria were studies with Aronia as intervention, performed in individuals with cardiometabolic disease or risk factors, e. g., type 2 diabetes (T2D), cardiovascular disease, hypertension, dyslipidaemia, impaired glucose tolerance, overweight, central obesity and smoking. Four of these studies were applicable for a quantitative analysis. RESULTS: Aronia did not influence body weight, circulating triglycerides, total cholesterol, high-density lipoprotein (HDL) cholesterol, or blood pressure. The quantitative analysis revealed a mean reduction in blood glucose of 0.44 mmol/l (P=0.0001) in the treatment group compared with the control group suggesting that Aronia treatment may have a beneficial impact on blood glucose. In addition, treatment durations of 6 weeks to 3 months tended to decrease low-density lipoprotein (LDL) cholesterol, while shorter treatment durations had no effect on LDL cholesterol. The quantitative analysis did not provide data on long-term effects of Aronia on lipids. CONCLUSIONS: More long-term high-quality randomized controlled studies are needed to clarify if dietary supplementation with Aronia has beneficial effects on cardiometabolic diseases.

The Effects of 12-Weeks Whey Protein Supplements on Markers of Bone Turnover in Adults With Abdominal Obesity - A Post Hoc Analysis.

Background: While osteoporosis is characterized by skeletal fragility due to increased bone turnover and low bone mineral density (BMD), subjects with abdominal obesity and type-2 diabetes have increased risk of bone fractures despite low bone turnover and increased BMD. Diets with increased protein content are reported to increase bone turnover in healthy adults and may be a point of interest in preserving bone strength in subjects with abdominal obesity and/or type-2 diabetes. Methods: We examined the effect of 12-weeks dietary intervention on bone turnover in 64 adults with abdominal obesity using data from the MERITS trial. The trial was a randomized, controlled, double blinded study in which participants were allocated to receive either 60 g/d of whey protein hydrolysate or maltodextrin in combination with either high (30 g/d) or low dietary fiber intake (10 g/d). Primarily, we assessed changes in plasma markers of bone turnover Procollagen type 1 N-terminal propeptide (p1NP), C-terminal telopeptide type-1 collagen (CTX), and parathyroid hormone (PTH) within the four intervention groups. In addition, we measured u-calcium and u-carbamide excretion, 25(OH)D, and BMD by whole body DXA scans. Finally, we compared changes in insulin resistance (Homeostasis-model assessment of insulin resistance, HOMA-IR) with changes in bone turnover markers.The trial was registered at www.clinicaltrials.gov as NCT02931630. Results: Sixty-four subjects were included in the study. We did not find any effect of twelve weeks of high protein or high fiber intake on plasma levels of P1NP or CTX. There was a nonsignificant positive association between protein intake and PTH levels (p=0.06). U-calcium and u-carbamide increased in both protein groups. There was a positive association between change in HOMA-IR and PTH (p=0.042), while changes in P1NP and CTX did not associate to changes in HOMA-IR. Conclusion: Twelve weeks of increased whey protein intake in subjects with abdominal obesity did not affect markers of bone turnover significantly, although tended to increase PTH levels. Dietary fiber intake did not affect bone turnover. We report a positive association between change in HOMA-IR and PTH supporting a hypothesis of insulin resistance as a potential key factor in the expanding field of bone fragility in T2D subjects.

The risk of major osteoporotic fractures with GLP-1 receptor agonists when compared to DPP-4 inhibitors: A Danish nationwide cohort study.

Background: Type 2 diabetes mellitus (T2D) is associated with an increased fracture risk. There is little evidence for the effects of glucagon-like peptide 1 receptor agonists (GLP-1RA) on fracture risk in T2D. We aimed to investigate the risk of major osteoporotic fractures (MOF) for treatment with GLP-1RA compared to dipeptidyl peptidase 4 inhibitors (DPP-4i) as add-on therapies to metformin. Methods: We conducted a population-based cohort study using Danish national health registries. Diagnoses were obtained from discharge diagnosis codes (ICD-10 and ICD-8-system) from the Danish National Patient Registry, and all redeemed drug prescriptions were obtained from the Danish National Prescription Registry (ATC classification system). Subjects treated with metformin in combination with either GLP-1RA or DPP-4i were enrolled from 2007 to 2018. Subjects were propensity-score matched 1:1 based on age, sex, and index date. MOF were defined as hip, vertebral, humerus, or forearm fractures. A Cox proportional hazards model was utilized to estimate hazard rate ratios (HR) for MOF, and survival curves were plotted using the Kaplan-Meier estimator. In addition, Aalen's Additive Hazards model was applied to examine additive rather than relative hazard effects while allowing time-varying effects. Results: In total, 42,816 individuals treated with either combination were identified and included. After matching, 32,266 individuals were included in the main analysis (16,133 in each group). Median follow-up times were 642 days and 529 days in the GLP-1RA and DPP-4i group, respectively. We found a crude HR of 0.89 [0.76-1.05] for MOF with GLP-1RA compared to DPP-4i. In the fully adjusted model, we obtained an unaltered HR of 0.86 [0.73-1.03]. For the case of hip fracture, we found a crude HR of 0.68 [0.49-0.96] and a similar adjusted HR. Fracture risk was lower in the GLP-1RA group when examining higher daily doses of the medications, when allowing follow-up to continue after medication change, and when examining hip fractures, specifically. Additional subgroup- and sensitivity analyses yielded results similar to the main analysis. Conclusion: In our primary analysis, we did not observe a significantly different risk of MOF between treatment with GLP-1RA and DPP-4i. We conclude that GLP-1RA are safe in terms of fracture.

SGLT2 inhibitor treatment is not associated with an increased risk of osteoporotic fractures when compared to GLP-1 receptor agonists: A nationwide cohort study.

Background: Type 2 diabetes mellitus (T2D) is associated with an increased fracture risk. It is debated whether sodium-glucose cotransporter 2 (SGLT2) inhibitors influence fracture risk in T2D. We aimed to investigate the risk of major osteoporotic fractures (MOF) with SGLT2 inhibitors compared to glucagon-like peptide 1 (GLP-1) receptor agonists when used as add-on therapies to metformin. Methods: We conducted a population-based cohort study using Danish national health registries. Diagnoses were obtained from discharge diagnosis codes (ICD-10 and ICD-8-system) from the Danish National Patient Registry, and all redeemed drug prescriptions were obtained from the Danish National Prescription Registry (ATC classification system). Subjects treated with metformin in combination with either SGLT2 inhibitors or GLP-1 receptor agonists were identified and enrolled from 2012 to 2018. Subjects were then propensity-score matched 1:1 based on age, sex, and index date. Major osteoporotic fractures (MOF) were defined as hip, vertebral, humerus, or forearm fractures. A Cox proportional hazards model was utilized to estimate hazard rate ratios (HR) for MOF, and survival curves were plotted using the Kaplan-Meier estimator. Results: In total, 27,543 individuals treated with either combination were identified and included. After matching, 18,390 individuals were included in the main analysis (9,190 in each group). Median follow-up times were 355 [interquartile range (IQR) 126-780] and 372 [IQR 136-766] days in the SGLT2 inhibitor and GLP-1 receptor agonist group, respectively. We found a crude HR of 0.77 [95% CI 0.56-1.04] for MOF with SGLT2 inhibitors compared to GLP-1 receptor agonists. In the fully adjusted model, we obtained an unaltered HR of 0.77 [95% CI 0.56-1.05]. Results were similar across subgroup- and sensitivity analyses. Conclusion: These results suggest that SGLT2 inhibitors have no effect on fracture risk when compared to GLP-1 receptor agonists. This is in line with results from previous studies.

Bone Density and Structure in Overweight Men With and Without Diabetes.

Objective: Metabolic syndrome (MetS), type 1 diabetes (T1D), and type 2 diabetes, are associated with an increased risk of fractures; however, the impact of obesity on bone deficits in diabetes is unknown. We aimed to compare markers of bone structure, bone density, and bone turnover in non-diabetic overweight men with MetS and overweight men with T1D or T2D. Methods and Research Design: In this cross-sectional study we included participants from two previously described study cohorts consisting of participants with diabetes and participants with MetS. Participants underwent dual-energy X-ray absorptiometry measuring areal bone mineral density (aBMD) at the hip and lumbar spine, High Resolution peripheral Quantitative (HRpQCT) scan of the tibia and radius and measurement of circulating bone turnover markers. We compared groups with unpaired t test and performed multiple linear regression with adjustment for age, body mass index, and smoking. Results: We included 33 participants with T1D, 25 participants with T2D, and 34 participants with MetS. Bone turnover markers levels were comparable between T1D and MetS. aBMD at the hip was lower in T1D compared to MetS, also after adjustment. P1NP and Osteocalcin levels were lower among individuals with T2D compared to MetS, whereas aBMD were similar between the groups after multiple adjustments. We observed no difference in volumetric BMD at the tibia or radius between MetS and T1D and T2D, respectively. Participants with T2D had a higher trabecular number and lower trabecular separation compared to individuals with MetS at the tibia, which remained signficant after multiple adjustments. Conclusion: In conclusion, we observed no clinically important differences in bone density or structure between men with T2D, T1D, or MetS. However, men with T2D displayed lower bone turnover compared to MetS highlighting that T2D per se and not obesity, is associated with low bone turnover.

Amino acid-induced gene expression profiling in clonal ß-cell line INS-1E cells.

BACKGROUND: There is abundant evidence that glucotoxicity and lipotoxicity contribute to impaired ß-cell function in type 2 diabetes. Interestingly, amino acid (AA) derangement is also a characteristic part of the diabetic state. The acute effects of AA on pancreatic ß-cell function have been widely explored; however, to our knowledge, the chronic effects of AA, e.g. proline (Pro), homocysteine (Hcy), and leucine (Leu), on pancreatic ß-cell function and integrity have not yet been studied. We aimed to investigate global alterations in ß-cell gene expression after long-term exposure of clonal INS-1E cells to elevated level of specific AA in vitro. METHODS: Global gene expression profiling was performed to characterize genes differently modified by Pro, Hcy, and Leu, respectively, in INS-1E cells. RESULTS: Gene expression profiling revealed significant changes in INS-1E cell mRNAs involved in the control of several aspects of ß-cell function, e.g. epigenetic regulation of gene expression, metabolism, innate and adaptive immune responses, cellular signalling, protein synthesis, apoptosis, and cellular stress response. After 72 h, INS-1E cells were differentially regulated (≥1.5- or ≤ -1.5-fold) by Pro (295 transcripts), Hcy (301 transcripts), and Leu (701 transcripts). It appears that Hcy effects changes opposite to those induced by Leu and/or Pro. CONCLUSIONS: AA appears to participate in and to influence many physiological processes including those involved in cholesterol metabolism, immune responses, and oxidative phosphorylation. Whether such events promote the ß-cell dysfunction and the ß-cell failure in diabetes remains to be elucidated. Our data strongly indicate that AA elevation may take part in the progressive development of type 2 diabetes.