Fructus Lycii and Salvia miltiorrhiza Bunge extract alleviate retinitis pigmentosa through Nrf2/HO-1 signaling pathway.

Fructus Lycii and Salvia miltiorrhiza Bunge (FS) are popular Chinese herbs for the treatment of retinitis pigmentosa (RP). This study was to evaluate protective effects of FS extract on RP and to explore whether FS extract exerts its protective effects via oxidative stress by regulating Nrf2/HO-1 signaling pathway. FS extract were identified by UPLC chromatographic analysis. Rd10 mice as the model of RP, followed by a 4-week FS extract treatment by intragastric administration. After the animal sacrifice, histopathological examination and Scotopic electroretinography (ERG) analysis were assessed. The oxidative stress markers were determined and the expression levels of Nrf2 and HO-1 mRNA were evaluated by qRT-PCR. The expression and distribution of Nrf2 and HO-1 protein were determined by Western blot and immunohistochemistry. The morphological changes of Outer nuclear layer (ONL) thickness and number of the ONL were observed with a significant increased, and the functional changes of a-amplitude and b-wave amplitude were measured with a markedly increased. Treatment with FS extract remarkably increased levels of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), and decreased level of malondialdehyde (MDA). Moreover, FS extract up-regulated mRNA and protein expression of Nrf2 and HO-1. This study indicated that FS extract can improve retinal morphology and function, which may have occurred through the regulation of the Nrf2/HO-1 pathway to inhibit the oxidative reaction. [Display omitted] • Fructus Lycii and Salvia miltiorrhiza Bunge extract improve retinal morphology and function. • Regulation of the Nrf2/HO-1 pathway inhibit the oxidative reaction. • Fructus Lycii and Salvia miltiorrhiza Bunge extract against retinitis pigmentosa was first explored in oxidative stress. [ABSTRACT FROM AUTHOR]