Islet inflammation impairs the pancreatic beta-cell in type 2 diabetes.
ABSTRACT Onset of Type 2 diabetes occurs when the pancreatic beta-cell fails to adapt to the increased insulin demand caused by insulin resistance. Morphological and therapeutic intervention studies have uncovered an inflammatory process in islets of patients with Type 2 diabetes characterized by the presence of cytokines, immune cells, beta-cell apoptosis, amyloid deposits, and fibrosis. This insulitis is due to a pathological activation of the innate immune system by metabolic stress and governed by IL-1 signaling. We propose that this insulitis contributes to the decrease in beta-cell mass and the impaired insulin secretion observed in patients with Type 2 diabetes.
- SourceAvailable from: PubMed Central[Show abstract] [Hide abstract]
ABSTRACT: Stem cell therapy has recently been introduced to treat patients with type 2 diabetes mellitus (T2DM). However, no data are available on the efficacy and safety of allogeneic Wharton's Jelly-derived mesenchymal stem cell (WJ-MSC) transplantation in patients with T2DM. Here we performed a non-placebo controlled prospective phase I/II study to determine efficacy and safety of WJ-MSC transplantation in T2DM. Twenty-two patients with T2DM were enrolled and received WJ-MSC transplantation through one intravenous injection and one intrapancreatic endovascular injection (catheterization). They were followed up for 12 months after transplantation. The primary endpoints were changes in the levels of glycated hemoglobin and C-peptide and the secondary endpoints included insulin dosage, fasting blood glucose (FBG), post-meal blood glucose (PBG), inflammatory markers and T lymphocyte counts. WJ-MSC transplantation significantly decreased the levels of glucose and glycated hemoglobin, improved C-peptide levels and beta cell function, and reduced markers of systemic inflammation and T lymphocyte counts. No major WJ-MSC transplantion-related adverse events occurred, but data suggest a temporary decrease in levels of C-peptide and beta cell function at one month after treatment, possibly related to intrapancreatic endovascular injection. Our data demonstrate that treatment with WJ-MSCs can improve metabolic control and beta cell function in patients with T2DM. The therapeutic mechanism may involve improvements in systemic inflammation and/or immunological regulation.Trial registration: Chinese Clinical Trial Register ChiCTR-ONC-10000985. Registered 23 September 2010.Stem Cell Research & Therapy 04/2014; 5(2):57. · 3.65 Impact Factor
- [Show abstract] [Hide abstract]
ABSTRACT: Immunologic and inflammatory processes are involved in the pathogenesis of acute coronary syndrome (ACS) and type 2 diabetes mellitus (DM2). Human leukocyte antigen-G (HLA-G) is a negative regulator of the immune response. This study evaluates the 14 bp Del/Ins HLA-G polymorphism in ACS and DM2. Three hundred and seventy individuals from Western Mexico were recruited and categorized into three groups: ACS (86), DM2 without coronary complications (70), and healthy subjects (214). Genotyping of the 14 bp Del/Ins HLA-G polymorphism was performed by PCR and Native-PAGE. The most common risk factors were hypertension and overweight in ACS and DM2, respectively. The genetic distribution of the 14 bp Del/Ins HLA-G polymorphism showed no significant differences between groups (P ≥ 0.23). Nonetheless, the Ins/Ins genotype was associated with high blood pressure (HBP) in the DM2 group (ORc = 1.65, P = 0.02). The genetic recessive model showed similar findings (ORc = 3.03, P = 0.04). No association was found in ACS, with a P of 0.05; nevertheless, the prevalence of Ins/Ins carriers was quite similar to that found in the DM2-HBP group. The 14 bp Del/Ins HLA-G polymorphism was not a susceptibility factor for ACS or DM2; however, the Ins/Ins genotype might have contributed to the development of HBP in the studied groups.BioMed research international. 01/2014; 2014:898159.
- [Show abstract] [Hide abstract]
ABSTRACT: Chronic inflammation-mediated beta-cell apoptosis is known to decrease beta-cell mass in diabetes leading to reduced insulin secretion. Exposure to pro-inflammatory cytokines can stimulate apoptosis in pancreatic beta-cells. The G protein coupled receptor 40 (GPR40) is implicated for glucose induced insulin secretion. We hypothesized that GPR40 activation can protect beta-cells from inflammation-induced apoptosis and restore glucose stimulated insulin secretion.BMC Cell Biology 06/2014; 15(1):24. · 2.81 Impact Factor