Ameliorative effect of black raspberry anthocyanins on diabetes retinopathy by inhibiting axis protein tyrosine phosphatase 1B-endoplasmic reticulum stress

Diabetes retinopathy (DR) is a common complication associated with diabetes. This study aimed to investigate ameliorative effect of black raspberry anthocyanins (BRAs) on DR and underlying inhibition mechanism of protein tyrosine phosphatase 1B (PTP1B)-endoplasmic reticulum stress (ERS) with retinal pigment epithelial cells apoptosis exposed to high glucose and tunicamycin and DR rats induced by STZ and high-fat and high-sugar diet. The results showed that TG and TC levels were markedly decreased, and disarrangement of retinas was markedly improved after BRA administration. Moreover, after pre-incubation with BRAs, morphological changes and mitochondrial membrane potential were significantly improved, whereas the apoptosis rates, activities of PTP1B and Caspase-1, and reactive oxygen species levels were significantly decreased. Finally, BRAs exhibited an efficient combination with GRP78, and they significantly suppressed protein expression of axis PTP1B-ERS. The results offer a basis for mastering ameliorated DR with BRAs and further first enhanced the mechanism of inhibiting axis PTP1B-ERS.

Automated summary

This study aimed to investigate the ameliorative effect of black raspberry anthocyanins (BRAs) on diabetes retinopathy (DR) and the underlying inhibition mechanism of protein tyrosine phosphatase 1B (PTP1B)-endoplasmic reticulum stress (ERS). The results showed that BRAs significantly improved the disarrangement of retinas and decreased TC and TG levels. Additionally, BRAs effectively improved cell morphology, mitochondrial membrane potential, and decreased apoptosis rates, PTP1B and Caspase-1 activities, and reactive oxygen species levels. Furthermore, BRAs exhibited a strong combination with GRP78 and suppressed the protein expression of the PTP1B-ERS axis.