Type 2 diabetes mellitus and the risk of abnormal spermatozoa: A Mendelian randomization study

Abnormal spermatozoa can not only reduce the fertilization rate, but also prolong the natural conception time and even increase the risk of spontaneous miscarriage. Diabetes mellitus (DM) has become a major global health problem, and its incidence continues to rise, while affecting an increasing number of men in their reproductive years. Type 2 Diabetes Mellitus (T2DM), accounting for about 85-95% of DM, is closely related to the development of sperm. However, the exact association between T2DM and abnormal spermatozoa remains unclear. Herein, we designed a Two-sample Mendelian randomization (MR) study to explore the causal association between T2DM and abnormal spermatozoa risk in European population data which come from the GWAS summary datasets. We selected 9 single nucleotide polymorphisms (SNPs) of T2DM (exposure data) as instrumental variables (IVs), and then retrieved the suitable abnormal spermatozoa genome-wide association study (GWAS) data of European from Ieu Open GWAS Project database which includes 915 cases and 209,006 control as the outcome data. Our results indicate that strict T2DM might not result in a higher risk of abnormal spermatozoa genetically in Europeans (OR: 1.017, 95% confidence interval (CI): 0.771-1.342, p=0.902). Our findings demonstrate that only T2DM may not explain the relatively higher risk of abnormal spermatozoa in men with it in Europeans. In subsequent studies, more comprehensive and larger samples need to be studied to reveal the relationship and potential mechanism between T2DM and abnormal spermatozoa.

Investigations into the Role of Metabolism in the Inflammatory Response of BV2 Microglial Cells

Although the hallmarks of Alzheimer's disease (AD) are amyloid beta plaques and neurofibrillary tangles, there is growing evidence that neuroinflammation, mitochondrial dysfunction and oxidative stress play important roles in disease development and progression. A major risk factor for the development of AD is diabetes, which is also characterized by oxidative stress and mitochondrial dysfunction along with chronic, low-grade inflammation. Increasing evidence indicates that in immune cells, the induction of a pro-inflammatory phenotype is associated with a shift from oxidative phosphorylation (OXPHOS) to glycolysis. However, whether hyperglycemia also contributes to this shift is not clear. Several different approaches including culturing BV2 microglial cells in different carbon sources, using enzyme inhibitors and knocking down key pathway elements were used in conjunction with bacterial lipopolysaccharide (LPS) activation to address this question. The results indicate that while high glucose favors NO production, pro-inflammatory cytokine production is highest in the presence of carbon sources that drive OXPHOS. In addition, among the carbon sources that drive OXPHOS, glutamine is a very potent inducer of IL6 production. This effect is dampened in the presence of glucose. Together, these results may provide new prospects for the therapeutic manipulation of neuroinflammation in the context of diabetes and AD.

Novel biological therapies for the treatment of diabetic foot ulcers

INTRODUCTION

The number of people with diabetes mellitus (DM) is estimated to exceed 640 million by the year 2040. Diabetic foot ulcer (DFU) is a debilitating illness that affects more than 2% of DM patients. DFU is caused by DM-induced neural and vascular lesions leading to a reduced sensation and microcirculation. The increase in the prevalence of DFU has prompted researchers to find new therapies for the management of DFU. Areas covered: This review presents the current status of novel biological therapies used in the treatment of DFU. Literature information and data analysis were collected from PubMed, the website of the American Diabetes Association, and ClinicalTrials.gov. The keywords used in the search were: DM, DFU, complications of DM. Expert opinion: Many biological agents have been investigated in a bid to find an effective therapy for DFU. These include growth factors (platelet-derived growth factor, vascular endothelial growth factor etc), stem cells (epithelial progenitor-, adipose-derived stem cells etc), anti-diabetic drugs (insulin, exendin-4), herbs, urokinase, dalteparin, statins and bio-agents such as acid peptide matrix. Biological agents that can reduce hyperglycaemia, increase sensation, microcirculation and oxygenation and repair lost tissue are the most ideal for the treatment of DFU.

Attenuation of oxidative stress in Type 1 diabetic rats supplemented with a seasoning obtained from winemaking by-products and its effect on endothelial function

A new red wine pomace seasoning (RWPS) induced remarkable anti-hyperglycemic effects and amelioration of vascular oxidative stress in Type 1 diabetic (DB) rats.

Effects of Nigella sativa L. seed oil on intima-media thickness and Bax and Caspase 3 expression in diabetic rat aorta

OBJECTIVE

Hyperglycaemia is an important risk factor for the development and progression of the macrovascular and microvascular complications that occur in diabetes. The expression of apoptotic markers in the aortic medial layer of diabetic rats and the effects of N. sativa L. seed oil on the expression of these markers were investigated in this study.

METHODS

Four-month-old adult female Wistar rats (n=21) were divided into 3 groups: Group 1, control; Group 2, diabetes and Group 3, diabetes+N. sativa L. seed oil. Group 3 received 0.2 mg/kg/day N. sativa L. seed (black cumin) oil intraperitoneally 6 days per week for 30 days. At the end of the experiment, abdominal and thoracic aortas of all animals were collected and fixed in 10% formalin solution. Then, 5-μm-thick sections were stained with Verhoeff-Van Gieson stain to evaluate Bax and Caspase 3 expression. Tunica intima-media thickness was measured using the stained sections.

RESULTS

There were no significant differences in abdominal or thoracic aortic intima-media thickness among the 3 groups. However, there were significant differences in Bax and Caspase 3 expression in the tunica media of the thoracic and abdominal aortas between Group 1 and Group 2 (p<0.05) and between Group 2 and Group 3 (p<0.05) evaluated with the Kruskal-Wallis and Mann-Whitney U tests.

CONCLUSION

It is understood that N. sativa L. seed oil is effective against diabetes. N. sativa L. seed oil is a plant material and has value for further investigation to develop diabetes treatment strategies for preventing apoptosis in vascular structures.

Vascular effects of advanced glycation endproducts: Clinical effects and molecular mechanisms

The enhanced generation and accumulation of advanced glycation endproducts (AGEs) have been linked to increased risk for macrovascular and microvascular complications associated with diabetes mellitus. AGEs result from the nonenzymatic reaction of reducing sugars with proteins, lipids, and nucleic acids, potentially altering their function by disrupting molecular conformation, promoting cross-linking, altering enzyme activity, reducing their clearance, and impairing receptor recognition. AGEs may also activate specific receptors, like the receptor for AGEs (RAGE), which is present on the surface of all cells relevant to atherosclerotic processes, triggering oxidative stress, inflammation and apoptosis. Understanding the pathogenic mechanisms of AGEs is paramount to develop strategies against diabetic and cardiovascular complications.

Fisetin lowers methylglyoxal dependent protein glycation and limits the complications of diabetes

The elevated glycation of macromolecules by the reactive dicarbonyl and α-oxoaldehyde methylglyoxal (MG) has been associated with diabetes and its complications. We have identified a rare flavone, fisetin, which increases the level and activity of glyoxalase 1, the enzyme required for the removal of MG, as well as the synthesis of its essential co-factor, glutathione. It is shown that fisetin reduces two major complications of diabetes in Akita mice, a model of type 1 diabetes. Although fisetin had no effect on the elevation of blood sugar, it reduced kidney hypertrophy and albuminuria and maintained normal levels of locomotion in the open field test. This correlated with a reduction in proteins glycated by MG in the blood, kidney and brain of fisetin-treated animals along with an increase in glyoxalase 1 enzyme activity and an elevation in the expression of the rate-limiting enzyme for the synthesis of glutathione, a co-factor for glyoxalase 1. The expression of the receptor for advanced glycation end products (RAGE), serum amyloid A and serum C-reactive protein, markers of protein oxidation, glycation and inflammation, were also increased in diabetic Akita mice and reduced by fisetin. It is concluded that fisetin lowers the elevation of MG-protein glycation that is associated with diabetes and ameliorates multiple complications of the disease. Therefore, fisetin or a synthetic derivative may have potential therapeutic use for the treatment of diabetic complications.

Oxidative stress and redox modulation potential in type 1 diabetes

Redox reactions are imperative to preserving cellular metabolism yet must be strictly regulated. Imbalances between reactive oxygen species (ROS) and antioxidants can initiate oxidative stress, which without proper resolve, can manifest into disease. In type 1 diabetes (T1D), T-cell-mediated autoimmune destruction of pancreatic β-cells is secondary to the primary invasion of macrophages and dendritic cells (DCs) into the islets. Macrophages/DCs, however, are activated by intercellular ROS from resident pancreatic phagocytes and intracellular ROS formed after receptor-ligand interactions via redox-dependent transcription factors such as NF-κB. Activated macrophages/DCs ferry β-cell antigens specifically to pancreatic lymph nodes, where they trigger reactive T cells through synapse formation and secretion of proinflammatory cytokines and more ROS. ROS generation, therefore, is pivotal in formulating both innate and adaptive immune responses accountable for islet cell autoimmunity. The importance of ROS/oxidative stress as well as potential for redox modulation in the context of T1D will be discussed.

A review on the beneficial aspects of food processing

The manuscript reviews beneficial aspects of food processing with main focus on cooking/heat treatment, including other food-processing techniques (e.g. fermentation). Benefits of thermal processing include inactivation of food-borne pathogens, natural toxins or other detrimental constituents, prolongation of shelf-life, improved digestibility and bioavailability of nutrients, improved palatability, taste, texture and flavour and enhanced functional properties, including augmented antioxidants and other defense reactivity or increased antimicrobial effectiveness. Thermal processing can bring some unintentional undesired consequences, such as losses of certain nutrients, formation of toxic compounds (acrylamide, furan or acrolein), or of compounds with negative effects on flavour perception, texture or colour. Heat treatment of foods needs to be optimized in order to promote beneficial effects and to counteract, to the best possible, undesired effects. This may be achieved more effectively/sustainably by consistent fine-tuning of technological processes rather than within ordinary household cooking conditions. The most important identified points for further study are information on processed foods to be considered in epidemiological work, databases should be built to estimate the intake of compounds from processed foods, translation of in-vitro results to in-vivo relevance for human health should be worked on, thermal and non-thermal processes should be optimized by application of kinetic principles.

A novel impedance-based cellular assay for the detection of anti-calcium channel autoantibodies in type 1 diabetes

We have recently postulated that functional autoantibodies (Abs) against L-type voltage-gated calcium channels (VGCCs) contribute to autonomic dysfunction in type 1 diabetes (T1D). Previous studies based on whole-organ assays have proven valuable in establishing the mechanism of anti-VGCC Ab activity, but are complex and unsuitable for screening large patient cohorts. In the current study, we used real-time dynamic monitoring of cell impedance to demonstrate that anti-VGCC Abs from patients with T1D inhibit the adherence of Rin A12 cells. The functional effect of the anti-VGCC Abs was mimicked by the dihydropyridine agonist, Bay K8644, and reversed by the antagonist, nicardipine, providing a pharmacological link to the whole-organ studies. IVIg neutralized the effect on cell adhesion of the anti-VGCC Abs, consistent with the presence of anti-idiotypic Abs in IVIg that may prevent the emergence of pathogenic Abs in healthy individuals. The cell impedance assay can be performed in a 96 well plate format, and represents a simple method for detecting the presence of anti-VGCC activity in patient immunoglobulin (IgG). The new cell assay should prove useful for further studies to determine the prevalence of the Ab and its association with symptoms of autonomic dysfunction in patients with T1D.

A randomized clinical trial of the effectiveness of photon stimulation on pain, sensation, and quality of life in patients with diabetic peripheral neuropathy

CONTEXT

Peripheral neuropathy is one of the most common complications of diabetes.

OBJECTIVES

The purpose of this study was to evaluate the effects of photon stimulation on pain intensity, pain relief, pain qualities, sensation and quality of life (QOL) in patients with painful diabetic peripheral neuropathy.

METHODS

In this randomized, placebo-controlled trial, patients were assigned to receive either four photon stimulations (n=63) or four placebo (n=58) treatments. Pain intensity, pain relief, and pain qualities were assessed using self-report questionnaires. Sensation was evaluated using monofilament testing. QOL was measured using the Medical Outcomes Study Short Form-36 (SF-36). Multilevel regression model analyses were used to evaluate between-group differences in study outcomes.

RESULTS

No differences, over time, in any pain intensity scores (i.e., pain intensity immediately post-treatment, average pain, worst pain) or pain relief scores were found between the placebo and treatment groups. However, significant decreases, over time, were found in some pain quality scores, and significant improvements in sensation were found in patients who received the photon stimulation compared with placebo. In addition, patients in the treatment group reported significant improvements in SF-36 social functioning and mental health scores. Findings from a responder analysis demonstrated that no differences were found in the percentages of patients in the placebo and treatment groups who received 30% or more or 50% or more reduction in pain scores immediately post-treatment. However, significant differences were found in the distribution of the changes in pain relief scores, with most of the patients in the photon stimulation group reporting a slight (28.6%) to moderate (34.9%) improvement in pain relief from the beginning to the end of the study compared with no change in pain relief (43.1%) in the placebo group.

CONCLUSION

Four treatments with photon stimulation resulted in significant improvements in some pain qualities, sensation, and QOL outcomes in a sample of patients with a significant amount of pain and disability from their diabetes. A longer duration study is needed to further refine the photon stimulation treatment protocol in these chronically ill patients and to evaluate the sustainability of its effects.