Association between changes in the mRNA expression of platelet-activating factor receptor in peripheral blood mononuclear cells and progression of diabetic nephropathy.

INTRODUCTION: Several studies have recently pointed out the role of many inflammatory mediators in the progression of diabetes complications. We had previously demonstrated that mRNA expression of platelet-activating factor receptor (PAFR) in peripheral blood mononuclear cells (PBMCs) was associated with urinary albumin to creatinine ratio (ACR) and forearm flow-mediated dilatation in patients with type 2 diabetes. In an attempt to elucidate this association, patients were followed up for 1 year. MATERIALS AND METHODS: We recruited 95 patients from the hospital outpatient clinic, among whom 86 were followed up for 1 year (normoalbuminuria: 40 patients, microalbuminuria: 25 patients, macroalbuminuria: 21 patients). We then measured their baseline and 12 month characteristics and collected blood samples to extract PBMCs and measure gene expressions. RESULTS: Despite higher mRNA expression of PAFR in PBMCs among patients with macroalbuminuria, the rise in its value was not associated with biomarkers of nephropathy, while baseline values were not associated with progression of nephropathy. Moreover, changes in mRNA expression of PAFR were correlated with changes in ACR in all patients (r = 0.225, p = 0.037) and estimated glomerular filtration rate in patients with macroalbuminuria (r = - 0.438, p = 0.047) during the follow-up period. CONCLUSION: Our findings indicate that even though no causal relationship exists between diabetic nephropathy and elevated expression of PAFR in PBMCs, their close association signifies the presence of another common mechanism that could induce both events. Given these findings, the PAF/PAFR interaction could clarify corresponding mechanisms involved in diabetic complications.

mRNA expression of platelet activating factor receptor (PAFR) in peripheral blood mononuclear cells is associated with albuminuria and vascular dysfunction in patients with type 2 diabetes.

AIMS: Renal dysfunction in addition to diabetes is a serious risk factor for cardiovascular events. We hypothesized that some of the changes in gene expression in blood cells cause renal dysfunction and macrovascular disease through impaired endothelial function. This study aimed to define which changes in gene expression in peripheral blood mononuclear cells (PBMCs) are related to renal function parameters and endothelial function of large arteries in patients with type 2 diabetes mellitus (T2DM). METHODS: We recruited 95 patients with T2DM. After matching for gender, age, BMI and HbA1c levels, the patient cohort included 42 with normoalbuminuria, 28 with microalbuminuria, and 25 with macroalbuminuria. All patients in the three groups were assessed for urinary albumin to creatinine ratio (ACR), estimated glomerular filtration rate (eGFR), flow-mediated dilatation (FMD), and mRNA expression in PBMCs. RESULTS: The mRNA expression of platelet activating factor receptor (PAFR) differed most markedly between the three groups and was significantly higher in the macroalbuminuric group (p < 0.001 vs. normoalbuminuric group; p < 0.05 vs. microalbuminuric group). PAFR mRNA expression significantly correlated with log transformed ACR (ρ = 0.424, p < 0.001) but not eGFR. PAFR mRNA expression also had a significant negative correlation with FMD (ρ = -0.379, p < 0.001). Furthermore, the prevalence of macrovascular complications, particularly stroke, was significantly higher in patients with elevated PAFR mRNA expression in PBMCs. CONCLUSIONS: PAFR overexpression in PBMCs may link diabetic nephropathy to macroangiopathy through impairment of endothelial function in patients with T2DM.

Median neuropathy at the wrist as an early manifestation of diabetic neuropathy.

AIMS/INTRODUCTION: To elucidate the clinical significance of median neuropathy at the wrist (MN) in patients with diabetes. MATERIALS AND METHODS: In total, 340 patients with diabetes who were hospitalized for glycemic control were enrolled in the present study. The diagnoses of MN and diabetic polyneuropathy (DPN) were based on electrophysiological criteria. A total of 187 patients were divided into four subgroups: patients without MN or DPN; patients with MN without DPN; patients with MN and DPN; and patients with DPN without MN. Intergroup comparisons of clinical characteristics and results of nerve conduction studies were carried out. RESULTS: A total of 71 patients had neither MN nor DPN; 25 had MN, but no DPN; 55 had MN and DPN; and 36 had DPN, but no MN. In comparison with the MN and DPN group, the MN without DPN group included more patients in the early phase of diabetes (diagnosed within the past 5 years) and fewer patients with diabetic microangiopathy. Comparative median nerve conduction studies showed significantly lower motor and sensory nerve conduction velocities, longer F-wave latencies, and smaller sensory nerve action potentials in patients with MN and DPN than in those without DPN. CONCLUSIONS: MN in patients with diabetes could be attributed to an impairment in axonal function at common entrapment sites, and could be used to identify an early manifestation of diabetic neuropathy.