Study on amelioration of Dendrobium chrysotoxum on STZ-induced non-proliferative diabetic retinopathy and its engaged mechanism / 中草药

ABSTRACT

Objective: To observe the amelioration of ethanol extract from Dendrobium chrysotoxum (EEDC) on non-proliferative diabetic retinopathy (NPDR) induced by streptozotocin (STZ), and further to investigate its engaged mechanism. Methods: NPDR was induced by STZ injection in C57 mice and then the diabetic mice were orally given EEDC. The retinal blood-retinal barrier (BRB) breakdown was evaluated using Evans blue leakage assay. The mRNA expression of interleukin (IL)-1β, IL-6, tumor necrosis factor (TNF) α, early growth response-1 (Egr-1), tissue factor (TF), and Serpine 1 in retinas was detected by real-time PCR. The amount of IL-1β, IL-6, TNF-α, TF, and Serpine 1 in serum was detected by enzyme-linked immunosorbent assay (ELISA). Results: EEDC at both doses reduced the increased Evans blue leakage in STZ-induced NPDR in mice. Results: of Real-Time PCR showed that EEDC reduced the increased retinal mRNA expression of IL-1β, IL-6, TNFα and Egr-1, TF, Serpine 1 in STZ-induced NPDR in mice. ELISA results also confirmed that EEDC reduced the increased serum levels of IL-1β, IL-6, TNF-α, TF, and Serpine 1 in STZ-induced NPDR in mice. Conclusion: EEDC could ameliorate the STZ-induced NPDR in mice via inhibiting retinal BRB breakdown by reducing the expression of pro-inflammatory cytokines including IL-1β, IL-6, TNF-α, and coagulation-fibrinolysis related signals such as TF and Serpine 1.