Effect of perceived stress, concern about hypoglycaemia and level of knowledge of management of the disease on glycaemic control in type 1 diabetes mellitus.

AIMS AND OBJECTIVES: To evaluate perceived stress, concern about hypoglycaemia and the level of knowledge of management of the disease in patients with type 1 diabetes mellitus and their relationship with glycaemic control, gender and age. BACKGROUND: Perceived stress and concern about hypoglycaemia are significant obstacles to achieving adequate glycaemic control in patients with type 1 diabetes mellitus, and notably influence management of the disease itself. MATERIAL AND METHODS: A cross-sectional study was carried out in 193 adult patients with type 1 diabetes mellitus. Study quality was scored using the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) checklist for cohort studies. Glycaemic control was evaluated by number and type of hypoglycaemic event and glycosylated haemoglobin. Questionnaires about hypoglycaemia concern (HFS II), perceived stress (PSS), unrecognised hypoglycaemia (Clarke Test) and level of knowledge of the disease were completed. RESULTS: Perceived stress was significantly associated with glycosylated haemoglobin (p < 0.001) and concern about hypoglycaemia (p < 0.037). With respect to level of knowledge, we observed that an advanced level was associated with lower glycosylated haemoglobin (p < 0.001), number (p < 0.001) and type (p < 0.001) of hypoglycaemic episode, and less perceived stress (p = 0.006). In addition, age was negatively correlated with perceived stress (p < 0.030) and positively correlated with the number of unrecognised hypoglycaemic episodes (p < 0.002), which was associated, in turn, with a higher number of daily glycaemia tests (p < 0.037) and concern about hypoglycaemia (p < 0.006). CONCLUSION: In type 1 diabetes mellitus, perceived stress can negatively influence glycaemic control and concern about hypoglycaemia, and level of knowledge about the condition has a bearing on glycosylated haemoglobin levels, perceived stress and number and type of hypoglycaemic events. In addition, higher age is associated with more frequent unrecognised hypoglycaemic events. RELEVANCE TO CLINICAL PRACTICE: It is essential to identify and address the psychological needs of patients with type 1 diabetes mellitus with the aim of achieving an adequate management of the disease itself and generating a change in future intervention strategies.

The Hybrid Closed-Loop System Tandem t:slim X2™ with Control-IQ Technology: Expert Recommendations for Better Management and Optimization.

Technological advances in the management of diabetes, especially type 1 diabetes (T1D), have played a main role in significantly improving glycemic control of these patients in recent years. Undoubtedly, the most important advance has been the commercialization of hybrid closed-loop systems (HCL). Their effectiveness places them in the different guidelines from scientific societies as the gold standard for the treatment of people with T1D. However, obtaining the maximum performance from these systems requires a degree of expertise from the professionals who care for these patients. Specifically, the Tandem X2:slim with Control-IQ technology system, due to its features and configuration options and adjustments, allows T1D patients to better adapt the management of diabetes to multiple circumstances in their day-to-day life. It is necessary, however, to follow a systematic process to start the system and also for the subsequent follow-up, which allows its optimization in the shortest possible time. This expert recommendation reviews the main features of this HCL system, suggesting how to implement it and optimize its use after gaining experience treating many patients.

Association between gut microbiota and psychiatric disorders: a systematic review.

Introduction: In recent years, it has been described that the dysbiosis of the intestinal microbiota plays a transcendental role in several pathologies. In this sense, the importance of the gut microbiota in the gut-brain axis, with a bidirectional communication, has been demonstrated. Furthermore, the gut microbiota has been linked with mood disorders and neuropsychiatric disorders. Methods: A systematic review of two databases - PubMed and Scopus - was carried out following PRISMA guidelines. We included original studies in humans with a control group published in the last 11 years, which were assessed by the Critical Appraisal Skills Program (CASP) to confirm their quality. Eighteen articles met all the selection criteria. Results: A review of the articles revealed an association between psychiatric disorders and different bacterial phyla. The studies we have reviewed have demonstrated differences between subjects with psychiatric disorders and controls and highlight a clear relationship between depression, stress, autism spectrum disorder (ASD), psychotic episodes, eating disorders, anxiety and brain function and the gut microbiota composition. Conclusion: A reduction of fermentative taxa has been observed in different psychiatric disorders, resulting in a decrease in the production of short-chain fatty acids (SCFAs) and an increase in pro-inflammatory taxa, both of which may be consequences of the exacerbation of these pathologies.

Effects of GLP-1 receptor agonists on mitochondrial function, inflammatory markers and leukocyte-endothelium interactions in type 2 diabetes.

OBJECTIVE: Type 2 diabetes (T2D) is linked to metabolic, mitochondrial and inflammatory alterations, atherosclerosis development and cardiovascular diseases (CVDs). The aim was to investigate the potential therapeutic benefits of GLP-1 receptor agonists (GLP-1 RA) on oxidative stress, mitochondrial respiration, leukocyte-endothelial interactions, inflammation and carotid intima-media thickness (CIMT) in T2D patients. RESEARCH DESIGN AND METHODS: Type 2 diabetic patients (255) and control subjects (175) were recruited, paired by age and sex, and separated into two groups: without GLP-1 RA treatment (196) and treated with GLP-1 RA (59). Peripheral blood polymorphonuclear leukocytes (PMNs) were isolated to measure reactive oxygen species (ROS) production by flow cytometry and oxygen consumption with a Clark electrode. PMNs were also used to assess leukocyte-endothelial interactions. Circulating levels of adhesion molecules and inflammatory markers were quantified by Luminex's technology, and CIMT was measured as surrogate marker of atherosclerosis. RESULTS: Treatment with GLP-1 RA reduced ROS production and recovered mitochondrial membrane potential, oxygen consumption and MPO levels. The velocity of leukocytes rolling over endothelial cells increased in PMNs from GLP-1 RA-treated patients, whereas rolling and adhesion were diminished. ICAM-1, VCAM-1, IL-6, TNFα and IL-12 protein levels also decreased in the GLP-1 RA-treated group, while IL-10 increased. CIMT was lower in GLP-1 RA-treated T2D patients than in T2D patients without GLP-1 RA treatment. CONCLUSIONS: GLP-1 RA treatment improves the redox state and mitochondrial respiration, and reduces leukocyte-endothelial interactions, inflammation and CIMT in T2D patients, thereby potentially diminishing the risk of atherosclerosis and CVDs.

Effect of weight loss on C3 and C4 components of complement in obese patients.

BACKGROUND: Circulating C3 levels are elevated in obese patients, but how this factor is affected after weight loss through diet is a question that is yet unanswered. Therefore, the aim of this study was to evaluate the effects of weight loss on lipid and hydrocarbonated metabolism parameters and on the levels of C3 and C4 components of complement in obese patients. DESIGN: This is a longitudinal intervention study based on a 6-week very low-calorie diet (VLCD), a liquid formula of 603 kcal/day. A total of 131 middle-aged patients were distributed among grades II, III and IV of obesity. Anthropometric parameters, total cholesterol, triglycerides, high-density lipoprotein cholesterol, LDLc, apolipoproteins A-I and B-100, glucose, insulin, HOMA-IR and C3 and C4 levels were evaluated at baseline and after 6 weeks of intervention. RESULTS: After VLCD, the moderate weight loss was accompanied by a significant reduction in C3 levels in grade III and grade IV patients (10.2% and 15.4%, respectively; P < 0.001). C4 levels were not altered. Adherence to the diet improved anthropometric parameters and was accompanied by a significant decrease in all lipid profile parameters (P < 0.001). In addition, weight loss was associated with an improvement in hydrocarbonated metabolism as shown by the decrease in glucose levels and HOMA-IR (P < 0.01). CONCLUSIONS: Our findings show that in severely obese patients following a VLCD for 6 weeks produces reductions in factor C3, a biomarker of cardiovascular disease, and a significant improvement in some features of metabolic syndrome. In this way, the abovementioned diet may represent an effective strategy for treating obesity and related cardiovascular risk factors.

Psychometric properties of a questionnaire to measure adherence to treatment in patients with type 1 diabetes mellitus.

AIM: To validate the psychometric properties of a questionnaire to measure adherence to treatment among people with type 1 diabetes mellitus and to evaluate its relationship with metabolic control. DESIGN: A cross-sectional study of 167 adult people with type 1 diabetes mellitus recruited from the Endocrinology Service of University Hospital Doctor Peset (Spain). METHODS: The validity of the content, construct and reliability of the instrument were evaluated and the results correlated with levels of glycosylated haemoglobin. RESULTS: The questionnaire was composed of 25 items and 5 dimensions, with a score of 25-150 points and an internal consistency of 0.92, according to Cronbach's coefficient α. The content of validity ratio and the construct (exploratory functional analysis, Kaiser-Meyer-Olkin index and Barlett's spherical test) were adequate. We observed a significant correlation between glycosylated haemoglobin levels and treatment adherence. CONCLUSION: The questionnaire to measure adherence to treatment in type 1 diabetes mellitus is consistent, reliable and valid, showing an excellent association with degree of metabolic control.

The Role of Mitochondrial Dynamic Dysfunction in Age-Associated Type 2 Diabetes.

Mitochondrial dynamics, such as fusion and fission, play a critical role in maintaining cellular metabolic homeostasis. The molecular mechanisms underlying these processes include fusion proteins (Mitofusin 1 [MFN1], Mitofusin 2 [MFN2], and optic atrophy 1 [OPA1]) and fission mediators (mitochondrial fission 1 [FIS1] and dynamin-related protein 1 [DRP1]), which interact with each other to ensure mitochondrial quality control. Interestingly, defects in these proteins can lead to the loss of mitochondrial DNA (mtDNA) integrity, impairment of mitochondrial function, a severe alteration of mitochondrial morphology, and eventually cell death. Emerging evidence has revealed a causal relationship between dysregulation of mitochondria dynamics and age-associated type 2 diabetes, a metabolic disease whose rates have reached an alarming epidemic-like level with the majority of cases (59%) recorded in men aged 65 and over. In this sense, fragmentation of mitochondrial networks is often associated with defects in cellular energy production and increased apoptosis, leading, in turn, to excessive reactive oxygen species release, mitochondrial dysfunction, and metabolic alterations, which can ultimately contribute to ß-cell dysfunction and insulin resistance. The present review discusses the processes of mitochondrial fusion and fission and their dysfunction in type 2 diabetes, with special attention given to the therapeutic potential of targeting mitochondrial dynamics in this complex metabolic disorder.

Institutional Experience With New Antidiabetic Drugs in Kidney Transplant.

BACKGROUND: The recent introduction of new antidiabetic drugs, analogs of glucagon-like peptide-1 (GLP-1) and sodium-glucose cotransporter 2 inhibitors, has shown excellent results in the management of patients with diabetes with chronic kidney disease. However, documented results of these medications in the population that has undergone kidney transplant are sparse. We report our institutional experience with them, including occurrence of side effects and possible interactions with immunosuppressive medications. METHODS: A retrospective analysis of 15 patients (10 with diabetes and 5 without diabetes but with obesity) managed with these medications was carried out in the kidney transplant unit of Hospital Doctor Peset during the year 2019. Data acquired at baseline and 3, 6, and 12 months were analyzed. RESULTS: The median hemoglobin A1c at baseline was 6.7 (interquartile range [IQR] = 5.8-8.2) and at 12 months it was 6 (IQR = 5.3-8.1, P = .96). The mean weight difference at 12 months was a loss of 7.2 ± 6 kg; median body mass index at baseline was 31.2 kg/m2 (IQR = 29.7-35.5) and 29.5 kg/m2 (IQR = 27.6-31.6, P = .01) at 12 months. In addition to weight loss, a reduction in insulin and oral antidiabetic drug requirements was observed. No significant changes were detected in serum creatinine or proteinuria values and the immunosuppressant levels remained stable. No acute rejection episodes were observed. CONCLUSION: Based on our experience, the new antidiabetic drugs are safe, with no significant changes in renal function or immunosuppressant levels or clinically important adverse effects.

Does Empagliflozin Modulate Leukocyte-Endothelium Interactions, Oxidative Stress, and Inflammation in Type 2 Diabetes?

Sodium-glucose co-transporter 2 inhibitors (iSGLT2) have been linked to cardiovascular risk reduction in patients with type 2 diabetes (T2D). However, their underlying molecular mechanisms remain unclear. This study aimed to evaluate the effects of empagliflozin, a novel potent and selective iSGLT-2, on anthropometric and endocrine parameters, leukocyte-endothelium interactions, adhesion molecules, ROS production, and NFkB-p65 transcription factor expression. According to standard clinical protocols, sixteen T2D patients receiving 10 mg/day of empagliflozin were followed-up for 24 weeks. Anthropometric and analytical measurements were performed at baseline, 12 weeks, and 24 weeks. Interactions between polymorphonuclear leukocytes and human umbilical vein endothelial cells (HUVECs), serum levels of adhesion molecules (P-Selectin, VCAM-1 and ICAM-1) and pro-inflammatory cytokines (TNF-α, IL-1ß and IL-6), mitochondrial ROS levels, antioxidant enzymes (SOD1 and GPX1), and NFkB-p65 were measured. We observed a decrease in body weight, BMI, and HbA1C levels from 12 weeks of treatment, which became more pronounced at 24 weeks and was accompanied by a significant reduction in waist circumference and glucose. Leukocyte-endothelium interactions were reduced due to an enhancement in the leukocyte rolling velocity from 12 weeks onwards, together with a significant decrease in leukocyte rolling flux and adhesion at 24 weeks. Accordingly, a significant decrease in ICAM-1 levels, mitochondrial ROS levels, and IL-6 and NFkB-p65 expression was observed, as well as an increase in SOD1. This pilot study provides evidence of the anti-inflammatory and antioxidant properties of empagliflozin treatment in humans, properties which may underlie its beneficial cardiovascular effects.

Parameters of inflammation in morbid obesity: lack of effect of moderate weight loss.

BACKGROUND: Obesity has been associated with a chronic activation of the acute-phase response. The aims of our study were to investigate whether levels of inflammatory cytokines are higher in obese patients, to evaluate their relationship with metabolic syndrome, and to analyze the effect of moderate weight loss upon their levels. METHODS: Sixty-seven severe or morbid obese patients were compared with 67 controls. Patients were submitted to a 4-week very low calorie diet followed by a low calorie diet for 2 months. Exclusion criteria were organic disease, ischemic heart disease or stroke, diabetes mellitus, hyperlipidemia, and hypertension. An evaluation was performed before and after the diet, in which fibrinogen, blood count, high-sensitive C-reactive protein (CRP), interleukin 6 (IL-6), and tumoral necrosis factor alpha (TNF-alpha) were measured. The Student t test was employed to compare differences between the groups and Pearson correlation coefficients were calculated. RESULTS: Obese patients showed higher levels of CRP (P < 0.001), IL-6 (P < 0.001), TNF-alpha (P < 0.001), leukocyte (P = 0.001), and neutrophil count (P < 0.001) than controls. In obese patients, inflammatory parameters were significantly correlated with anthropometric parameters and did not differ between obese subjects with or without metabolic syndrome. Moderate weight loss (excess weight loss 19.6%) was achieved through dieting, but no change was observed in any inflammatory parameter. CONCLUSIONS: Obesity is associated to a chronic inflammatory state that seems to be due to an increased secretion of cytokines, and this state is not related to the presence of metabolic syndrome. Moderate weight loss does not ameliorate this inflammatory state in the short term.

Activated protein C levels in obesity and weight loss influence.

Obesity is associated with a high risk of cardiovascular events. Several haemostatic disturbances which could contribute to this increased risk have been described in obesity; nevertheless, the state of coagulation inhibitors has been scarcely studied in these patients. The aim of the present study was to compare activated protein C levels in obese patients and in a control group, and to evaluate the effect of weight loss. In 67 severe or morbid obese patients, an evaluation was performed at baseline and 3 months after diet. The same determinations were performed in 67 healthy volunteers with normal body weight. We also quantified the levels of protein C and prothrombin fragment 1+2. Obese patients showed significantly higher levels of activated protein C, protein C and fragment 1+2. No correlation was found between activated protein C and fragment 1+2 levels in obese patients. After three months of diet, a significant decrease in activated protein C and fragment 1+2 was observed. In conclusion, activated protein C levels are increased in obese patients, but only a minor fraction of this increase may be explained by the higher thrombin generation and C protein levels. Activated protein C levels decrease with weight loss, due in part to a thrombin generation reduction.

Small and dense LDL in familial combined hyperlipidemia and N291S polymorphism of the lipoprotein lipase gene.

There is a predominance of small and dense LDL cholesterol particles in familial combined hyperlipidemia (FCH). The lipoprotein lipase gene could exert an influence in these circumstances.To study the relationship of pattern B LDL and lipids with N291S polymorphism of lipoprotein lipase (LPL) in FCH patients.Lipid profile, apolipoproteins, diameter of LDL and N291S polymorphism were determined in 93 patients with FCH and 286 individuals from the general population.FCH patients with N291S polymorphism showed a lower mean diameter of LDL. FCH patients with pattern B LDL showed higher concentrations of triglycerides, VLDLc, non-HDLc and apo B100 and lower levels of HDLc than those with pattern A. Of FCH patients with polymorphism 87.5% presented pattern B and 12.5% pattern A, while patients without polymorphism presented pattern A in 69.2% cases and pattern B in 30.8% cases, with differences being statistically significant (p < 0.004). The prevalence of this mutation in our FCH patients was 9.7%.The prevalence of N291S mutation in our FCH patients was similar to the 9.3% described in Dutch FCHL patients but clearly higher than the 2-5% described for other Caucasian populations. No polymorphism was found in our general population sample. FCH patients with phenotype B of LDL possessed an atherogenic lipid profile. The relationship between small and dense LDL and the presence of the N291S mutation may identify patients with high cardiovascular risk.

The Mitochondrial Antioxidant SS-31 Modulates Oxidative Stress, Endoplasmic Reticulum Stress, and Autophagy in Type 2 Diabetes.

Mitochondrial dysfunction has been shown to play a central role in the pathophysiology of type 2 diabetes (T2D), and mitochondria-targeted agents such as SS-31 are emerging as a promising strategy for its treatment. We aimed to study the effects of SS-31 on leukocytes from T2D patients by evaluating oxidative stress, endoplasmic reticulum (ER) stress and autophagy. Sixty-one T2D patients and 53 controls were included. Anthropometric and analytical measurements were performed. We also assessed reactive oxygen species (ROS) production, calcium content, the expression of ER stress markers GRP78, CHOP, P-eIF2α, and autophagy-related proteins Beclin1, LC3 II/I, and p62 in leukocytes from T2D and control subjects treated or not with SS-31. Furthermore, we have evaluated the action of SS-31 on leukocyte-endothelium interactions. T2D patients exhibited elevated ROS concentration, calcium levels and presence of ER markers (GRP78 and CHOP gene expression, and GRP78 and P-eIF2α protein expression), all of which were reduced by SS-31 treatment. SS-31 also led to a drop in BECN1 gene expression, and Beclin1 and LC3 II/I protein expression in T2D patients. In contrast, the T2D group displayed reduced p62 protein levels that were restored by SS-31. SS-20 (with non-antioxidant activity) did not change any analyzed parameter. In addition, SS-31 decreased rolling flux and leukocyte adhesion, and increased rolling velocity in T2D patients. Our findings suggest that SS-31 exerts potentially beneficial effects on leukocytes of T2D patients modulating oxidative stress and autophagy, and ameliorating ER stress.

Does Glycemic Control Modulate the Impairment of NLRP3 Inflammasome Activation in Type 2 Diabetes?

Since mitochondrial dysfunction is associated with NOD-like receptor family protein 3 (NLRP3) activation in type 2 diabetes (T2D), which can eventually lead to an impaired immune response, we set out to determine if glycemic control modulates the effects of T2D on the NLRP3 inflammasome. We have studied leukocytes from 61 diabetic patients [25 with glycated hemoglobin (HbA1c) ≤7% and 36 with HbA1c ≥8%] and 40 healthy controls. Total and mitochondrial reactive oxygen species (ROS) production was enhanced in T2D patients, and mitochondrial ROS was more pronounced in those with poor glycemic control. Levels of gene and protein expression of NLRP3 were decreased in both diabetic groups and more so in those with HbA1c ≥8%. In addition, there was a decrease in gene expression and serum concentrations of interleukin (IL)-1ß, IL-12, and caspase-1 in line with inhibition of the NLRP3 inflammasome. Our data also suggest negative correlations between HbA1c levels and NLRP3 protein expression, serum levels of IL-12 and IL-1ß, and caspase-1 messenger RNA expression. Our findings lead us to raise the hypothesis of an association between poor glycemic control in T2D and an impairment of the NLRP3 inflammasome, suggesting that glycemic control plays an important role in the immune response of diabetic subjects.

Relationship Between Oxidative Stress, ER Stress, and Inflammation in Type 2 Diabetes: The Battle Continues.

Type 2 diabetes (T2D) is a metabolic disorder characterized by hyperglycemia and insulin resistance in which oxidative stress is thought to be a primary cause. Considering that mitochondria are the main source of ROS, we have set out to provide a general overview on how oxidative stress is generated and related to T2D. Enhanced generation of reactive oxygen species (ROS) and oxidative stress occurs in mitochondria as a consequence of an overload of glucose and oxidative phosphorylation. Endoplasmic reticulum (ER) stress plays an important role in oxidative stress, as it is also a source of ROS. The tight interconnection between both organelles through mitochondrial-associated membranes (MAMs) means that the ROS generated in mitochondria promote ER stress. Therefore, a state of stress and mitochondrial dysfunction are consequences of this vicious cycle. The implication of mitochondria in insulin release and the exposure of pancreatic ß-cells to hyperglycemia make them especially susceptible to oxidative stress and mitochondrial dysfunction. In fact, crosstalk between both mechanisms is related with alterations in glucose homeostasis and can lead to the diabetes-associated insulin-resistance status. In the present review, we discuss the current knowledge of the relationship between oxidative stress, mitochondria, ER stress, inflammation, and lipotoxicity in T2D.

Obesity and activated protein C resistance.

It has been reported that obesity may be associated with activated protein C resistance, which could increase the thrombotic risk in these patients. The aim of our study was to evaluate this parameter in obese patients and controls, as well as the effect of weight loss on this parameter. In 63 severely or morbidly obese patients and in 65 healthy volunteers, an anthropometric and analytical evaluation (activated protein C resistance and prothrombin fragment F1 + 2) was performed at baseline and after 3 months of diet. Obese patients showed higher levels of F1 + 2 than controls, whereas activated protein C sensitivity ratios showed no differences. After weight loss, prothrombin fragment F1 + 2 was reduced, but no differences were found in activated protein C sensitivity. We did not find an activated protein C-resistant phenotype in obese subjects.

Plasminogen activator inhibitor-1 levels in severe and morbid obesity. Effect of weight loss and influence of 4G/5G polymorphism.

INTRODUCTION: An association between an increase in plasminogen activator inhibitor type 1 and obesity has been described. It has also been shown that a decrease in adiposity has beneficial effects. However, less information is available regarding morbid obesity and hypofibrinolysis. The aim of the present study was to evaluate the effect of weight loss and the influence of the plasminogen activator inhibitor type 1 promoter 4G/5G genotype on plasminogen activator inhibitor type 1 levels in severe and morbid obesity. MATERIALS AND METHODS: Sixty-seven obese patients were studied before and three months after a weight reduction program, and compared with 67 controls. We determined plasminogen activator inhibitor type 1 antigen and activity levels, tissue type plasminogen activator antigen levels, 4G/5G genotype and biochemical parameters in both groups. RESULTS: A significant increase in plasminogen activator inhibitor type 1 antigen and activity was observed in obese patients in comparison with the control group (P<0.001). No significant differences in plasminogen activator inhibitor type 1 levels among 4G/5G genotypes were obtained. After weight loss, a significant decrease in plasminogen activator inhibitor type 1 antigen and activity was observed (P<0.001). A significant and positive correlation was observed in percentage changes in plasminogen activator inhibitor type 1 and body mass index (P=0.02). CONCLUSIONS: A decrease in body mass index in severe and morbid obesity shows a favourable effect on the fibrinolytic system due to a decrease in plasminogen activator inhibitor type 1 levels. However, no influence of 4G/5G polymorphism has been observed in this setting.

Mitochondrial DNA Haplogroup JT is Related to Impaired Glycaemic Control and Renal Function in Type 2 Diabetic Patients.

The association between mitochondrial DNA (mtDNA) haplogroup and risk of type 2 diabetes (T2D) is undetermined and controversial. This study aims to evaluate the impact of the main mtDNA haplogroups on glycaemic control and renal function in a Spanish population of 303 T2D patients and 153 healthy controls. Anthropometrical and metabolic parameters were assessed and mtDNA haplogroup was determined in each individual. Distribution of the different haplogroups was similar in diabetic and healthy populations and, as expected, T2D patients showed poorer glycaemic control and renal function than controls. T2D patients belonging to the JT haplogroup (polymorphism m.4216T>C) displayed statistically significant higher levels of fasting glucose and HbA1c than those of the other haplogroups, suggesting a poorer glycaemic control. Furthermore, diabetic patients with the JT haplogroup showed a worse kidney function than those with other haplogroups, evident by higher levels of serum creatinine, lower estimated glomerular filtration rate (eGFR), and slightly higher (although not statistically significant) urinary albumin-to-creatinine ratio. Our results suggest that JT haplogroup (in particular, change at position 4216 of the mtDNA) is associated with poorer glycaemic control in T2D, which can trigger the development of diabetic nephropathy.

Does Metformin Modulate Endoplasmic Reticulum Stress and Autophagy in Type 2 Diabetic Peripheral Blood Mononuclear Cells?

Since type 2 diabetes (T2D) is associated with oxidative stress and metformin has been shown to exert a protective role against the said stress, we wondered whether metformin treatment might also modulate endoplasmic reticulum (ER) stress and autophagy in leukocytes of T2D patients. We studied 53 T2D patients (37 of whom had been treated with metformin 1700 mg for at least 1 year) and 30 healthy volunteers. Leukocytes from both groups of T2D patients exhibited increased protein levels of 78-kDa glucose-regulated protein (GRP78) with respect to controls, whereas activating transcription factor 6 (ATF6) was enhanced specifically in nonmetformin-treated T2D, and (s-xbp1) and phosphorylated eukaryotic initiation factor 2α (p-eIF2α) increased only in the metformin-treated group. The autophagy markers beclin1 (becn1), autophagy-related 7 (atg7), and microtubule-associated protein 1A/1B-light chain 3II/I (LC3 II/I) increased in nonmetformin-treated T2D, and metformin treatment reduced mitochondrial superoxide and increased glutathione (GSH) levels. Our observations raise the question of whether metformin treatment could reduce oxidative stress and act as an ER stress modulator in T2D patients by promoting an adaptive unfolded protein response (s-xbp1 and p-eIF2α) in their leukocytes; this was in contrast with nonmetformin-treated patients whose response could be driven by the ATF6-dependent pro-apoptotic pathway. Further, our findings lead to us to form the hypothesis of an autophagy-dependent clearance of misfolded proteins in nonmetformin-treated T2D patients that could be repressed by metformin treatment.-Antioxid. Redox Signal. 28, 1562-1569.

Role of Oxidative Stress and Mitochondrial Dysfunction in Skeletal Muscle in Type 2 Diabetic Patients.

Type 2 diabetes can increase the risk of skeletal muscle dysfunction and, consequently, that of cardiovascular diseases, including coronary artery disease and stroke. It is also related to a reduced capacity for exercise, but the underlying mechanism is only partially understood. There are several factors that contribute to the development of skeletal muscle dysfunction, of which oxidative stress and mitochondrial dysfunction are among the most important. This review discusses the role of oxidative stress in the development and progression of skeletal and cardiac dysfunction associated with diabetes. It also provides an overview of the potential actions of antioxidants in general and mitochondria-targeted antioxidants in particular in the treatment of muscle dysfunction in type 2 diabetes.