No abstract

We confirm that MSC-derived EV contribute to angiogenesis, showing that they may not only exert a direct stimulus to EC proliferation, but also induce pericyte detachment, thus leaving EC free to proliferate. In addition, we demonstrate a possible link between EV and the early stages of the pathogenesis of DR. Diabetic-like conditions may influence vessel remodelling during angiogenesis through EV paracrine signalling.

Functional analysis of miR-21-3p, miR-30b-5p and miR-150-5p shuttled by extracellular vesicles from diabetic subjects reveals their association with diabetic retinopathy

Thiamine prevents high glucose-induced damage in microvasculature, and progression of retinopathy and nephropathy in diabetic animals. Impaired thiamine availability causes renal damage in diabetic patients. Two single-nucleotide polymorphisms in SLC19A3 locus encoding for thiamine transporter 2 are associated with absent/minimal diabetic retinopathy and nephropathy despite long-term type 1 diabetes. We investigated the involvement of thiamine transporter 1 and thiamine transporter 2, and their transcription factor specificity protein 1, in high glucose-induced damage and altered thiamine availability in cells of the inner blood–retinal barrier. Human endothelial cells, pericytes and Müller cells were exposed to hyperglycaemic-like conditions and/or thiamine deficiency/over-supplementation in single/co-cultures. Expression and localization of thiamine transporter 1, thiamine transporter 2 and transcription factor specificity protein 1 were evaluated together with intracellular thiamine concentration, transketolase activity and permeability to thiamine. The effects of thiamine depletion on cell function (viability, apoptosis and migration) were also addressed. Thiamine transporter 2 and transcription factor specificity protein 1 expression were modulated by hyperglycaemic-like conditions. Transketolase activity, intracellular thiamine and permeability to thiamine were decreased in cells cultured in thiamine deficiency, and in pericytes in hyperglycaemic-like conditions. Thiamine depletion reduced cell viability and proliferation, while thiamine over-supplementation compensated for thiamine transporter 2 reduction by restoring thiamine uptake and transketolase activity. High glucose and reduced thiamine determine impairment in thiamine transport inside retinal cells and through the inner blood–retinal barrier. Thiamine transporter 2 modulation in our cell models suggests its major role in thiamine transport in retinal cells and its involvement in high glucose-induced damage and impaired thiamine availability.

Background and aims: Diabetes is a suitable model to evaluate intervention programmes aimed at chronic diseases, because of its well-defined and measurable process and outcome indicators. In this study, we aimed at investigating the effects of group based selfmanagement education on clinical and psychological variables in type 2 diabetes. Methods and results: Four-year randomized controlled clinical trial (ISRCTN14558376) comparing Group Care and traditional one-to-one care. Clinical and psychological variables were monitored at baseline, 2 and 4 years. Although differences between groups appear to be non-significant at univariate analysis, body weight, BMI and HbA1c, systolic and diastolic blood pressure improved in the patients followed by Group Care but not among Controls. Prescription of lipid-lowering and anti-hypertensive agents did not change among the patients on Group Care, whereas antihypertensives were stepped up among Controls without improving their blood pressure. Multivariable analysis suggests that blood pressure improvement among patients on Group Care was independent of BMI, duration of diabetes and antihypertensive medication, suggesting a direct effect of education, presumably by increasing adherence. The "Powerful Others" dimension of the Locus of Control worsened and fear of complications decreased among Controls. Conclusions: The results confirm that a multidisciplinary structured group educational approach improves blood pressure, presumably through better adherence to healthy lifestyle and medication, in people with type 2 diabetes. Clinical trial registration number: ISRCTN14558376.