The Effect of Vitamin-D on the Diabetic Rethinopathy

Background: To determine the relationship between grade of diabetic retinopathy and serum vitamin D levels in diabetic patients. Methods: The study included a total of 173 diabetic patients consisting of patients without retinopathy ( n=67), patients with non proliferative diabetic retinopathy (NPDRP group n=47), patients with proliferative diabetic retinopathy (PDRP group n=59). Age and sex-matched 55 healthy subjects was taken as a control group. Patients with type 1 DM, those taking vitamin D, multivitamin including vitamin D, drug affecting vitamin D metabolism like rifampin, phenytoin was excluded from the study. Patients with chronic renal failure was also excluded. Dilated fundoscopic examination of all subject was done and serum creatinine, Hb A1c, 25 hydroxyvitamin D (25 (OH) D) level of all subject were measured between may 2012 and September 2012 Results: There were no statistical difference in age, sex, systolic tension, diastolic tension and body mass index between groups. Serum creatinine level was also not statistically different between groups (p = 0.11). Serum fasting glucose and HbA1c level were significantly lower in the control group than diabetic groups (p <0.001). The mean 25 (OH)D levels of PDRP group, NPDRP group, diabetic patients without retinopathy and control group were 11,9 ± 6,4 ng/ml, 18,8 ± 10,2 ng/ml, 16,6 ± 7,5 ng/ml and 20,1 ± 9,2 ng/ml respectively. There was statistically significant difference between the PDRP group and other groups in univariate analysis (p < 0.001). When 173 diabetic patients, were compared, with control group, 25 (OH) D levels were significantly lower in diabetic patients than control group regardless of retinopathy status (p = 0.004). Conclusions: Diabetic patients especially, patients with proliferative diabetic retinopathy had lower serum vitamin D levels than healthy subjects. Additionally randomized, controlled, prospective studies are necessary to determine whether vitamin D treatment will stop or slow the progression of diabetic retinopathy in diabetic patients. © 2022 A. CARBONE Editore. All rights reserved

The pro-angiogenic properties of multi-functional bioactive glass composite scaffolds

The angiogenic properties of micron-sized (m-BG) and nano-sized (n-BG) bioactive glass (BG) filled poly(D,L lactide) (PDLLA) composites were investigated. On the basis of cell culture work investigating the secretion of vascular endothelial growth factor (VEGF) by human fibroblasts in contact with composite films (0, 5, 10, 20 wt %), porous 3D composite scaffolds, optimised with respect to the BG filler content capable of inducing angiogenic response, were produced. The in vivo vascularisation of the scaffolds was studied in a rat animal model and quantified using stereological analyses. The prepared scaffolds had high porosities (81 – 93 %), permeability (k = 5.4 – 8.6 × 10-9 m2) and compressive strength values (0.4 – 1.6 MPa) all in the range of trabecular bone. On composite films containing 20 wt % m-BG or n-BG, human fibroblasts produced 5 times higher VEGF than on pure PDLLA films. After 8 weeks of implantation, m-BG and n-BG containing scaffolds were well-infiltrated with newly formed tissue and demonstrated higher vascularisation and percentage blood vessel to tissue (11.6 – 15.1 %) than PDLLA scaffolds (8.5 %). This work thus shows potential for the regeneration of hard-soft tissue defects and increased bone formation arising from enhanced vascularisation of the construct