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 β-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.
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.
Retinol binding protein 4 (RBP4) is an adipokine that may contribute to the development of insulin resistance. However, how this adipokine is affected and its possible involvement in lipid metabolism ...in obese patients with varying degrees of insulin resistance is yet to be determined. A total of 299 middle-aged morbid obese patients (BMI>40 kg/m(2)) were divided in euglycemic, metabolic syndrome or type 2 diabetic. Anthropometric measurements, biochemical variables and systemic RBP4 levels were determined. RBP4 levels were significantly higher in patients with metabolic syndrome and type 2 diabetes than in euglycemic subjects (42.9±14.6; 42.3±17.0 and 37.4±11.7 µg/ml, respectively) and correlated with triglycerides but not with those of HOMA-IR in the whole population. The multivariate regression model revealed that triglycerides were the strongest predictor of systemic RBP4 levels. Analysis of lipoprotein subfractions in a subpopulation of 80 subjects showed an altered profile of insulin resistant states characterized by higher VLDL, sdLDL and small HDL percentages and lower large HDL percentage. Although RBP4 levels correlated significantly with LDL particle size and small HDL percentage, the latter parameter was independently associated only with RBP4. Our study reveals that systemic RBP4 levels could play an important role in lipid metabolism in morbid obesity, increasing triglyceride levels and contributing to the formation of small HDL.
Abstract Aims/hypothesis Alterations in circadian rhythms increase the likelihood of developing type 2 diabetes and CVD. Circadian rhythms are controlled by several core clock genes, which are ...expressed in nearly every cell, including immune cells. Immune cells are key players in the pathophysiology of type 2 diabetes, and participate in the atherosclerotic process that underlies cardiovascular risk in these patients. The role of the core clock in the leukocytes of people with type 2 diabetes and the inflammatory process associated with it are unknown. We aimed to evaluate whether the molecular clock system is impaired in the leukocytes of type 2 diabetes patients and to explore the mechanism by which this alteration leads to an increased cardiovascular risk in this population. Methods This is an observational cross-sectional study performed in 25 participants with type 2 diabetes and 28 healthy control participants. Clinical and biochemical parameters were obtained. Peripheral blood leukocytes were isolated using magnetic bead technology. RNA and protein lysates were obtained to assess clock-related gene transcript and protein levels using real-time PCR and western blot, respectively. Luminex XMAP technology was used to assess levels of inflammatory markers. Leukocyte–endothelial interaction assays were performed by perfusing participants’ leukocytes or THP-1 cells (with/without CLK8) over a HUVEC monolayer in a parallel flow chamber using a dynamic adhesion system. Results Participants with type 2 diabetes showed increased BMAL1 and NR1D1 mRNA levels and decreased protein levels of circadian locomotor output cycles kaput (CLOCK), cryptochrome 1 (CRY1), phosphorylated basic helix-loop-helix ARNT like 1 (p-BMAL1) and period circadian protein homologue 2 (PER2). Correlation studies revealed that these alterations in clock proteins were negatively associated with glucose, HbA 1c , insulin and HOMA-IR levels and leukocyte cell counts. The leukocyte rolling velocity was reduced and rolling flux and adhesion were enhanced in individuals with type 2 diabetes compared with healthy participants. Interestingly, inhibition of CLOCK/BMAL1 activity in leukocytes using the CLOCK inhibitor CLK8 mimicked the effects of type 2 diabetes on leukocyte–endothelial interactions. Conclusions/interpretation Our study demonstrates alterations in the molecular clock system in leukocytes of individuals with type 2 diabetes, manifested in increased mRNA levels and decreased protein levels of the core clock machinery. These alterations correlated with the impaired metabolic and proinflammatory profile of the participants with type 2 diabetes. Our findings support a causal role for decreased CLOCK/BMAL1 activity in the increased level of leukocyte–endothelial interactions. Overall, our data suggest that alterations in core clock proteins accelerate the inflammatory process, which may ultimately precipitate the onset of CVD in patients with type 2 diabetes. Graphical Abstract
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.
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 β-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.
•Little is known about the use of new antidiabetic drugs, glucagon-like peptide-1 analogs and sodium-glucose cotransporter 2 inhibitors, in the kidney transplant population.•New antidiabetic drugs ...have shown excellent results in the management of patients with diabetes.•Glucagon-like peptide-1 analogs and sodium-glucose cotransporter 2 inhibitors are safe, with no clinically important adverse effects.
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.
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.
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.
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.
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 (
and
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
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.
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.
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-1β 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.