Abstract
Purpose:
Diabetes mellitus is a metabolic disorder that results due to hyperglycemic condition for a prolonged duration and often leads to various ophthalmic complications. Cornea is one of the most severely affected ocular structures with devastating results including vision impairments, corneal edema, delayed wound healing, and ulcers. In this study we have developed a novel 3-dimensional in vitro model using primary human corneal stroma diabetic cells from Type I and Type II donors. We have identified key signaling pathways involved in corneal DM defects using our 3D in vitro that mirror what is seen in vivo.
Methods:
Human corneas stromal cells were isolated and cultured from healthy/no ocular disease (HCF) donors and from Type I (T1DM) and Type 2 (T2DM) diabetic donors. All cells were cultured on polycarbonate membranes for 4 week and stimulated with a stable Vitamin C (VitC) derivative. All constructs were processed for immunofluorescence, real time PCR, and western blot analysis.
Results:
Our data shows significant morphological changes between HCF and T1DM. T2DM appear similar to HCF with long spindle shape morphology while T1DM appear bigger, with multiple processors, and large cytoskeleton. In terms of ECM, both T1DM and T2DM assembled significant larger amount of ECM when compared to HCF (~40%; p<0.05). Collagen I was down regulated by at least 2-fold in both T1DM and T2DM, while Collagen III and α-SMA were only up-regulated in T1DM (15 and 5-fold respectively). IGF-1 and IGF-1R, previously linked to diabetes, were both up regulated in T2DM. T1DM showed significant up regulation of IGF-1R but not IGF1.
Conclusions:
Overall, we have developed a novel 3D in vitro model that allows for the study of cellular and ECM interactions, which may help understand the root problem of the human corneal diabetes. Diabetes has significant effect on morphological, metabolic, physiological, and clinical aspects of the cornea. The benefits of developing an in vitro model are enormous and provide clues for novel therapeutics to treat diabetes defects in cornea.<br />