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.

Impact of Roux-en-Y Gastric Bypass on Mitochondrial Biogenesis and Dynamics in Leukocytes of Obese Women.

The chronic low-grade inflammation widely associated with obesity can lead to a prooxidant status that triggers mitochondrial dysfunction. To date, Roux-en-Y gastric bypass (RYGB) is considered the most effective strategy for obese patients. However, little is known about its molecular mechanisms. This interventional study aimed to investigate whether RYGB modulates oxidative stress, inflammation and mitochondrial dynamics in the leukocytes of 47 obese women at one year follow-up. We evaluated biochemical parameters and serum inflammatory cytokines -TNFα, IL6 and IL1ß- to assess systemic status. Total superoxide production -dHe-, mitochondrial membrane potential -TMRM-, leucocyte protein expression of inflammation mediators -MCP1 and NF-kB-, antioxidant defence -GPX1-, mitochondrial regulation-PGC1α, TFAM, OXPHOS and MIEAP- and dynamics -MFN2, MNF1, OPA1, FIS1 and p-DRP1- were also determined. After RYGB, a significant reduction in superoxide and mitochondrial membrane potential was evident, while GPX1 content was significantly increased. Likewise, a marked upregulation of the transcription factors PGC1α and TFAM, complexes of the oxidative phosphorylation chain (I-V) and MIEAP and MFN1 was observed. We conclude that women undergoing RYGB benefit from an amelioration of their prooxidant and inflammatory status and an improvement in mitochondrial dynamics of their leukocytes, which is likely to have a positive effect on clinical outcome.

Gold Nanoparticles Supported on Ceria Nanoparticles Modulate Leukocyte-Endothelium Cell Interactions and Inflammation in Type 2 Diabetes.

Gold-ceria nanoparticles (Au/CeO2) are known to have antioxidant properties. However, whether these nanoparticles can provide benefits in type 2 diabetes mellitus (T2D) remains unknown. This work aimed to study the effects of Au/CeO2 nanoparticles at different rates of gold purity (10, 4.4, 1.79 and 0.82) on leukocyte-endothelium interactions and inflammation in T2D patients. Anthropometric and metabolic parameters, leukocyte-endothelium interactions, ROS production and NF-κB expression were assessed in 57 T2D patients and 51 healthy subjects. T2D patients displayed higher Body Mass Index (BMI) and characteristic alterations in carbohydrate and lipid metabolism. ROS production was increased in leukocytes of T2D patients and decreased by Au/CeO2 at 0.82% gold. Interestingly, Au/CeO2 0.82% modulated leukocyte-endothelium interactions (the first step in the atherosclerotic process) by increasing leukocyte rolling velocity and decreasing rolling flux and adhesion in T2D. A static adhesion assay also revealed diminished leukocyte-endothelium interactions by Au/CeO2 0.82% treatment. NF-κB (p65) levels increased in T2D patients and were reduced by Au/CeO2 treatment. Cell proliferation, viability, and apoptosis assays demonstrated no toxicity produced by Au/CeO2 nanoparticles. These results demonstrate that Au/CeO2 nanoparticles at 0.82% exert antioxidant and anti-inflammatory actions in the leukocyte-endothelium interaction of T2D patients, suggesting a protective role against the appearance of atherosclerosis and cardiovascular diseases when this condition exists.

Glycated Proteins, Glycine, Acetate, and Monounsaturated Fatty Acids May Act as New Biomarkers to Predict the Progression of Type 2 Diabetes: Secondary Analyses of a Randomized Controlled Trial.

Food protein or food-derived peptides may regulate blood glucose levels; however, studies have shown inconsistent results. The aim of the present study was to characterize subgroups of individuals with increased risk of type 2 diabetes (T2D) and to investigate the cardiometabolic effects of fish protein in the same subgroups. We first divided participants into high insuliniAUC and low insuliniAUC subjects based on their insulin incremental area under the curve (iAUC) levels after a 2 h oral glucose tolerance test (OGTT), and secondly based on whether they had received 5.2 g salmon fish protein or placebo for 8 weeks, in a previously conducted randomized controlled trial (RCT). We then profiled these groups by analyzing plasma metabolomics and peripheral blood mononuclear cell (PBMC) gene expression. Compared to the low insuliniAUC group, the high insuliniAUC group had higher plasma concentrations of monounsaturated fatty acids (MUFAs) and glycated proteins (GlycA) and lower concentrations of glycine and acetate. After intervention with fish protein compared to placebo, however, only acetate was significantly increased in the low insuliniAUC group. In conclusion, we identified metabolic biomarkers known to be associated with T2D; also, intervention with fish protein did not affect cardiometabolic risk markers in subgroups with increased risk of T2D.

Metformin modulates mitochondrial function and mitophagy in peripheral blood mononuclear cells from type 2 diabetic patients.

Type 2 diabetes is a chronic metabolic disease that affects mitochondrial function. In this context, the rescue mechanisms of mitochondrial health, such as mitophagy and mitochondrial biogenesis, are of crucial importance. The gold standard for the treatment of type 2 diabetes is metformin, which has a beneficial impact on the mitochondrial metabolism. In this study, we set out to describe the effect of metformin treatment on mitochondrial function and mitophagy in peripheral blood mononuclear cells (PBMCs) from type 2 diabetic patients. We performed a preliminary cross-sectional observational study complying with CONSORT requirements, for which we recruited 242 subjects, divided into 101 healthy volunteers, 93 metformin-treated type 2 diabetic patients and 48 non-metformin-treated type 2 diabetic patients. Mitochondria from the type 2 diabetic patients not treated with metformin displayed more reactive oxygen species (ROS) than those from healthy or metformin-treated subjects. Protein expression of the electron transport chain (ETC) complexes was lower in PBMCs from type 2 diabetic patients without metformin treatment than in those from the other two groups. Mitophagy was altered in type 2 diabetic patients, evident in a decrease in the protein levels of PINK1 and Parkin in parallel to that of the mitochondrial biogenesis protein PGC1α, both of which effects were reversed by metformin. Analysis of AMPK phosphorylation revealed that its activation was decreased in the PBMCs of type 2 diabetic patients, an effect which was reversed, once again, by metformin. In addition, there was an increase in the serum levels of TNFα and IL-6 in type 2 diabetic patients and this was reversed with metformin treatment. These results demonstrate that metformin improves mitochondrial function, restores the levels of ETC complexes, and enhances AMPK activation and mitophagy, suggesting beneficial clinical implications in the treatment of type 2 diabetes.

Does Metformin Modulate Mitochondrial Dynamics and Function in Type 2 Diabetic Patients?

Metformin is an effective drug against type 2 diabetes (T2D), a pathogenesis in which mitochondrial dysfunction is one of the main players. Thus, our first aim was to describe the effect of metformin on mitochondrial function in an outpatient population with T2D. For analyzing this hypothesis, we performed a preliminary cross-sectional study complying with the STROBE requirements. We studied leukocytes from 139 healthy controls, 39 T2D patients without metformin treatment, and 81 T2D patients who had been on said treatment for at least 1 year. Leukocytes from T2D patients displayed higher total and mitochondrial reactive oxygen species levels, lower mitochondrial membrane potential, and lower oxygen consumption. Moreover, their mitochondria expressed lower mRNA and protein levels of fusion proteins mitofusin-1 (MFN1), mitofusin-2 (MFN2), and optic atrophy 1 (OPA1), and higher protein and gene expression levels of mitochondrial fission protein 1 (FIS1) and dynamin-related protein 1 (DRP-1). In addition, we observed enhanced leukocyte/endothelial interactions in T2D patients. Metformin reversed most of these effects, ameliorating mitochondrial function and dynamics, and reducing the leukocyte/endothelial interactions observed in T2D patients. These results raise the question of whether metformin tackles T2D by improving mitochondrial dysfunction and regulating mitochondrial dynamics. Furthermore, it would seem that metformin modulates the alteration of interactions between leukocytes and the endothelium, a subclinical marker of early atherosclerosis. Antioxid. Redox Signal. 35, 377-385.

MicroRNAs and Oxidative Stress: An Intriguing Crosstalk to Be Exploited in the Management of Type 2 Diabetes.

Type 2 diabetes is a chronic disease widespread throughout the world, with significant human, social, and economic costs. Its multifactorial etiology leads to persistent hyperglycemia, impaired carbohydrate and fat metabolism, chronic inflammation, and defects in insulin secretion or insulin action, or both. Emerging evidence reveals that oxidative stress has a critical role in the development of type 2 diabetes. Overproduction of reactive oxygen species can promote an imbalance between the production and neutralization of antioxidant defence systems, thus favoring lipid accumulation, cellular stress, and the activation of cytosolic signaling pathways, and inducing ß-cell dysfunction, insulin resistance, and tissue inflammation. Over the last few years, microRNAs (miRNAs) have attracted growing attention as important mediators of diverse aspects of oxidative stress. These small endogenous non-coding RNAs of 19-24 nucleotides act as negative regulators of gene expression, including the modulation of redox signaling pathways. The present review aims to provide an overview of the current knowledge concerning the molecular crosstalk that takes place between oxidative stress and microRNAs in the physiopathology of type 2 diabetes, with a special emphasis on its potential as a therapeutic target.

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.

Phytosterols: Nutritional Health Players in the Management of Obesity and Its Related Disorders.

Obesity and its related disorders, such as diabetes and cardiovascular risk, represent an emerging global health issue. Even though genetic factors seem to be the primary actors in the development and progression of these diseases, dietary choices also appear to be of crucial importance. A healthy diet combined with physical activity have been shown to ameliorate glycaemic levels and insulin sensitivity, reduce body weight and the risk of chronic diseases, and contribute to an overall improvement in quality of life. Among nutrients, phytosterols have become the focus of growing attention as novel functional foods in the management of metabolic disorders. Phytosterols are natural plant compounds belonging to the triterpene family and are structurally similar to cholesterol. They are known for their cholesterol-lowering effects, anti-inflammatory and antioxidant properties, and the benefits they offer to the immune system. The present review aims to provide an overview of these bioactive compounds and their therapeutic potential in the fields of obesity and metabolic disorders, with special attention given to oxidative stress, inflammatory status, and gut dysbiosis, all common features of the aforementioned diseases.

Association between Proinflammatory Markers, Leukocyte-Endothelium Interactions, and Carotid Intima-Media Thickness in Type 2 Diabetes: Role of Glycemic Control.

Glycated hemoglobin monitorization could be a tool for maintaining type 2 diabetes (T2D) under control and delaying the appearance of cardiovascular events. This cross-sectional study was designed to assess the role of glycemic control in modulating early-stage markers of cardiovascular complications. One hundred and eight healthy controls and 161 type 2 diabetic patients were recruited and distributed according to their glycemic control, setting the threshold at 6.5% (good control). Biochemical and anthropometrical parameters were registered during the initial visit, and peripheral blood was extracted to obtain polymorphonuclear cells and analyze inflammatory markers, adhesion molecules, leukocyte-endothelium interactions, and carotid intima-media thickness. Correlations between these parameters were explored. We found that inflammatory markers and adhesion molecules were augmented in type 2 diabetic subjects with poor glycemic control. Polymorphonuclear leukocytes interacted more with the endothelium in the diabetic population, and even more significantly in the poorly controlled subjects. In parallel, carotid intima-media thickness was also increased in the diabetic population, and the difference was greater among poorly controlled subjects. Finally, correlation measurement revealed that carotid intima-media thickness was related to glycemic control and lipid metabolism in diabetic patients. Our results suggest that glycemic control delays the onset of cardiovascular comorbidities in diabetic subjects.

Mitochondrial Alterations and Enhanced Human Leukocyte/Endothelial Cell Interactions in Type 1 Diabetes.

Type 1 diabetes has been associated with oxidative stress. This study evaluates the rates of oxidative stress, mitochondrial function, leukocyte-endothelium interactions and adhesion molecules in type 1 diabetic patients. The study population consisted of 52 diabetic patients and 46 body-composition and age-matched controls. We assessed anthropometric and metabolic parameters, oxidative stress and mitochondrial function by evaluating reactive oxygen species (ROS) production, mitochondrial ROS production, mitochondrial membrane potential and superoxide dismutase (SOD) and catalase (CAT) expression in polymorphonuclear leukocytes from type 1 diabetic patients. In addition, we evaluated interactions between leukocytes and human umbilical vein endothelial cells (HUVEC), and serum expression of adhesion molecules (P-selectin, VCAM-1 and ICAM-1), proinflammatory cytokines (IL-6 and TNFα) and myeloperoxidase (MPO). HbA1C and glucose levels were higher in diabetic patients than in control subjects, as expected. Mitochondrial function was altered and leukocyte-endothelium interactions were enhanced in diabetic patients, which was evident in the increase in total and mitochondrial ROS production, higher mitochondrial membrane potential, enhanced leukocyte rolling and adhesion, and decreased rolling velocity. Furthermore, we observed an increase in levels of adhesion molecules P-selectin, VCAM-1, and ICAM-1 in these subjects. In addition, type 1 diabetic patients exhibited an increase in proinflammatory mediators TNFα and MPO, and a decreased expression of SOD. The enhancement of leukocyte-endothelium interactions and proinflammatory markers correlated with glucose and HbA1Clevels. Mitochondrial alteration, oxidative stress, and enhanced leukocyte-endothelium interactions are features of type 1 diabetes and may be related to cardiovascular implications.

Relationship between PMN-endothelium interactions, ROS production and Beclin-1 in type 2 diabetes.

Type 2 diabetes is closely related to oxidative stress and cardiovascular diseases. In this study, we hypothesized that polymorphonuclear leukocytes (PMN)-endothelium interactions and autophagy are associated. We evaluated PMN-endothelial interactions, ROS production and autophagy parameters in 47 type 2 diabetic patients and 57 control subjects. PMNs from type 2 diabetic patients exhibited slower rolling velocity (p < 0.001), higher rolling flux (p < 0.001) and adhesion (p < 0.001) in parallel to higher levels of total (p < 0.05) and mitochondrial ROS (p < 0.05). When the protein expression of autophagy markers was analysed, an increase of Beclin-1 (p < 0.05), LC3I (p < 0.05), LC3II (p < 0.01) and LC3II/LC3I ratio (p < 0.05) was observed. Several correlations between ROS and leukocyte-endothelium parameters were found. Interestingly, in control subjects, an increase of Beclin-1 levels was accompanied by a decrease in the number of rolling (r = 0.561) and adhering PMNs (r = 0.560) and a rise in the velocity of the rolling PMNs (r = 0.593). In contrast, in the type 2 diabetic population, a rise in Beclin-1 levels was related to an increase in the number of rolling (r = 0.437), and adhering PMNs (r = 0.467). These results support the hypothesis that PMN-endothelium interactions, ROS levels and formation of autophagosomes, especially Beclin-1 levels, are enhanced in type 2 diabetes.

Autophagy Stimulation as a Potential Strategy Against Intestinal Fibrosis.

We recently observed reduced autophagy in Crohn's disease patients and an anti-inflammatory effect of autophagy stimulation in murine colitis, but both anti- and pro-fibrotic effects are associated with autophagy stimulation in different tissues, and fibrosis is a frequent complication of Crohn's disease. Thus, we analyzed the effects of pharmacological modulation of autophagy in a murine model of intestinal fibrosis and detected that autophagy inhibition aggravates, while autophagy stimulation prevents, fibrosis. These effects are associated with changes in inflammation and in collagen degradation in primary fibroblasts. Thus, pharmacological stimulation of autophagy may be useful against intestinal fibrosis.

Conservative treatment of upper urinary tract carcinoma: Long-term results.

INTRODUCTION: We sought to assess the long-term results of conservative treatment for upper urinary tract carcinoma (UUTC) with regard to tumour recurrence and preservation of renal unit. METHODS: From October 1987 to January 2014, 65 patients (median age 68 years) were diagnosed with UUTC and underwent endoscopic and open surgical techniques. Thirteen patients had bilateral disease and one had a single kidney. The primary approach was endoscopic in 37 reno-ureteral units (20 percutaneous resections, 17 ureteroscopies ). Open surgery was performed in 19 cases. A total of 20 patients received mitomycin C. RESULTS: Superficial stage pTa or T1 was noted in 37 patients, infiltrating stage pT2 and pT3 in seven and inverted papilloma in one. The stage of the tumour was impossible to classify in 20. With a median followup of 75.12 months (interquartile range [IQR] 144.71-17.41), the kidney preservation, recurrence, specific survival, and global survival rates were 78.5% (51/65), 40.0% (26/65), 92.3% (60/65), and 69.2% (45/65), respectively. From the patients who had recurrence, 15 were salvaged with radical nephroureterectomy (RNU). The bladder tumour recurrence rate after the surgery was 30.76% (20/65). At the end of the followup, five patients had died of UUTC progression and 16 from other causes. Postoperative complications included one case of fistula, one case of stricture, and one case of nephrectomy due to bleeding. CONCLUSIONS: In selected cases, conservative management is a safe and feasible alternative to RNU, with the advantage of renal unit preservation.