The role of the immune system in the pathogenesis of diabetic complications

Human cell-based anti-inflammatory effects of rosiglitazone

PURPOSE

The C-X-C motif chemokine ligand 10 (CXCL10) participates in diabetes and diabetic cardiomyopathy development from the early stages. Rosiglitazone (RGZ) exhibits anti-inflammatory properties and can target cardiomyocytes secreting CXCL10, under interferon (IFN)γ and tumor necrosis factor (TNF)α challenge. Cardiomyocyte remodeling, CD4 + T cells and dendritic cells (DCs) significantly contribute to the inflammatory milieu underlying and promoting disease development. We aimed to study the effect of RGZ onto inflammation-induced secretion of CXCL10, IFNγ, TNFα, interleukin (IL)-6 and IL-8 by human CD4 + T and DCs, and onto IFNγ/TNFα-dependent signaling in human cardiomyocytes associated with chemokine release.

METHODS

Cells maintained within an inflammatory-like microenvironment were exposed to RGZ at near therapy dose (5 µM). ELISA quantified cytokine secretion; qPCR measured mRNA expression; Western blot analyzed protein expression and activation; immunofluorescent analysis detected intracellular IFNγ/TNFα-dependent trafficking.

RESULTS

In human CD4 + T cells and DCs, RGZ inhibited CXCL10 release likely with a transcriptional mechanism, and reduced TNFα only in CD4 + T cells. In human cardiomyocytes, RGZ impaired IFNγ/TNFα signal transduction, blocking the phosphorylation/nuclear translocation of signal transducer and activator of transcription 1 (Stat1) and nuclear factor-kB (NF-kB), in association with a significant decrease in CXCL10 expression, IL-6 and IL-8 release.

CONCLUSION

As the combination of Th1 biomarkers like CXCL10, IL-8, IL-6 with classical cardiovascular risk factors seems to improve the accuracy in predicting T2D and coronary events, future studies might be desirable to further investigate the anti-Th1 effect of RGZ.

The Lymphocyte Depletion in Patients with Acute Ischemic Stroke Associated with Poor Neurologic Outcome

Purpose

Inflammation plays an important role and is involved in all stages of acute ischemic stroke. One of these stages involves the recruitment of leukocytes from the peripheral circulation into the ischemic tissue. Lymphocytes as a subtype of leukocytes are important mediators and can become a predictor of neurological outcome. Several studies have been conducted regarding the correlation between differential lymphocyte counts and acute ischemic stroke. Most of these studies analyzed lymphocyte ratio to other leukocyte subtypes such as neutrophils and monocytes. This study specifically observed the role of lymphocytes as an indicator of the inflammatory response in patients with acute ischemic stroke. This study aimed to observe the correlation among risk factors, infarct location, leukocyte counts, lymphocyte value and neurologic output in acute ischemic stroke patients.

Patients and Methods

We observed and analyzed 193 patients’ data from medical record which met the inclusion and exclusion criteria with a diagnosis of acute ischemic stroke at the Department of Neurology of Dr. Hasan Sadikin General Bandung. Data were then analysed using appropriate statistical tests.

Results

Most patients have more than one risk factor with a leukocyte count of less than 10,000 cell/mm³. Infarct was mostly located in subcortical area (basal ganglia), with moderate average NIHSS values at admission and at discharge. The number of lymphocytes decreased in the subject group with more than 10,000 cell/mm³ leukocytes. Subsequently, data were analyzed using Spearman’s test and there was a correlation between NIHSS on admission and lymphocyte depletion.

Conclusion

The lymphocyte depletion in patients with leukocytosis is a predictor of poor NIHSS.

Toll-like Receptors as a Potential Drug Target for Diabetes Mellitus and Diabetes-associated Complications

Diabetes mellitus (DM) is a chronic endocrine disease distinguished by hyperglycemia due to disturbance in carbohydrate or lipid metabolism or insulin function. To date, diabetes, and its complications, is established as a global cause of morbidity and mortality. The intended aim during the management of diabetes is to maintain blood glucose close to normal because the majority of patients have poor control of their elevated blood glucose and are highly prone to severe macrovascular and microvascular complications. To decrease the burden of the disease and its complications, scientists from various disciplines are working intensively to identify novel and promising drug targets for diabetes and its complications. Increased and ongoing investigations on mechanisms relating to diabetes and associated complications could potentially consider inflammatory cascades as a promising component of the strategy in the prevention and control of diabetes and its complications. The potential of targeting mediators of inflammation like toll-like receptors (TLRs) are part of current investigation by the scientific community. Hence, the aim of the present review is to discuss the role of TLRs as a potential drug target for diabetes and diabetes associated complications.

Integrated Proteomic and Transcriptomic Analysis of Differential Expression of Chicken Lung Tissue in Response to NDV Infection during Heat Stress

Newcastle disease virus (NDV) is a devastating worldwide poultry pathogen with major implications for global food security. In this study, two highly inbred and genetically distinct chicken lines, Fayoumis and Leghorns, were exposed to a lentogenic strain of NDV, while under the effects of heat stress, in order to understand the genetic mechanisms of resistance during high ambient temperatures. Fayoumis, which are relatively more resistant to pathogens than Leghorns, had larger numbers of differentially expressed genes (DEGs) during the early stages of infection when compared to Leghorns and subsequently down-regulated their immune response at the latter stages to return to homeostasis. Leghorns had very few DEGs across all observed time points, with the majority of DEGs involved with metabolic and glucose-related functions. Proteomic analysis corroborates findings made within Leghorns, while also identifying interesting candidate genes missed by expression profiling. Poor correlation between changes observed in the proteomic and transcriptomic datasets highlights the potential importance of integrative approaches to understand the mechanisms of disease response. Overall, this study provides novel insights into global protein and expression profiles of these two genetic lines, and provides potential genetic targets involved with NDV resistance during heat stress in poultry.

Immunogenic lipid markers of atherosclerosis in type 2 diabetic patients on program haemodialysis

Aim. Determination of desialized apolipoprotein-B-100 (apoB-100) and lipoprotein-containing circulating immune complexes in patients with chronic kidney disease (CKD) in program hemodialysis with type 2 diabetes mellitus. Materials and methods. We examined 81 patients with CKD (50 men / 31 women) treated with program hemodialysis, of which 36 (17/19) with type 2 diabetes mellitus, 45 (33/12) non-diabetic patients. The levels of total cholesterol, triglycerides and desialylated apoB-100 in blood plasma and lipoprotein-containing circulating immune complexes. A color duplex scan of brachiocephalic arteries was used to assess the extent of development of atherosclerosis with the determination of the thickness of the intima-medial complex. Results and discussion. Patients with diabetes had high values of total cholesterol, triglycerides (p

Targeting heme oxygenase-1 in early diabetic nephropathy in streptozotocin-induced diabetic rats

Diabetic nephropathy (DN) is one of the most common microvascular diabetic complications. This study was designed to evaluate the possible protective effect and underlying mechanisms of HO-1 induction in streptozotocin (STZ)-induced early DN in rats. The diabetic rats were divided into three groups: STZ-diabetic, cobalt protoporphyrin (CoPP)-treated diabetic, and zinc protoporphyrin IX (ZnPP)-treated diabetic groups. Compared to the STZ-diabetic group, CoPP-induced HO-1 upregulation improved the diabetic state and renal functional parameters, suppressed the renal proinflammatory marker, NF-κB, abrogated the elevated renal hydroxyprolin, and decreased the enhanced renal nicotinamide adenine dinucleotide phosphate oxidase activity with parallel reduction of urinary oxidative stress markers. On the contrary, treatment with ZnPP abrogated HO-1 levels, aggravated the diabetic condition with further increases in renal oxidative stress, fibrotic and inflammatory markers, and exacerbated renal dysfunction in diabetic animals. These findings suggest that the reduced diabetic renal injury upon HO-1 induction implicates the role of HO-1 induction as a potential treatment for DN.