Effects of Goji with different origins or different extraction methods on primary mixed glial cells

Abstract

This article is to investigate the effect of wolfberry from different origins and extraction methods on mice primary brain glial cells and the antioxidant and anti-inflammatory effects of different Lycium barbarum extract on brain glial cells under oxidative stress. Primary mice brain glial cells were collected from the cerebral cortex of the newborn C57BL/6J mice and cultured for 10 to 14 d. After pre-treating Lycium barbarum extracts (LBE) with different origins and extraction methods for 2 h, 400 µmol/L hydrogen peroxide (H2O2) was treated to the primary mixed glial cells to establish an in vitro oxidative stress model. 4 kinds of LBEs at the dose of 500 µg/mL were treated to the cells for 6 and 24 h. After 6 h of intervention with LBEs, gene expression levels of anti-oxidative and inflammatory-related genes were detected in primary brain glial cells using quantitative PCR. After 24 h of LBEs intervention, the levels of lactate dehydrogenase (LDH) in the cell supernatant were detected using LDH assay kit, while the protein expression levels of PRDX5, SOD1, and SOD2 of each group were detected using Western blot assay. The results showed that, compared to the control group, the LDH release levels of mixed glial cells treated with 100 to 2000 µg/mL Ningxia LBE (NX), Xinjiang LBE (XJ), and Lycium barbarum polysaccharide-glycoprotein (LBP) did not increase significantly whereas the LDH level of cells treated with Qinghai LBE (QH) was significantly increased at the dose of 100 µg/mL. Under the challenge of H2O2, the cell viability of the LBP+H2O2 group was significantly higher compared to the H2O2 group, whereas there was no statistical difference in cell viability between the H2O2 group and the other 3 LBE+H2O2 groups. Compared to the H2O2 group, the Nrf-2 gene expression level of NX+H2O2 group and XJ+H2O2 group was significantly increased. The gene expression level of SOD1 of the LBP+H2O2 group was significantly increased. Also, the PRDX5 gene expression levels of NX+H2O2, QH+H2O2, and LBP+H2O2 groups were significantly increased. The expression level of SOD2 protein in the LBP+H2O2 group was significantly increased. Gene expressions of inflammatory-related factors were significantly increased in NX+H2O2, QH+H2O2, and LBP+H2O2 treatment groups. The results indicate that 4 kinds of Lycium barbarum extracts show anti-oxidative and anti-inflammatory capacity under oxidative stress. LBP and Ningxia LBE, which are both originated from Ningxia, have better antioxidant effects among these 4 kinds of LBEs. However, at the same time, LBP and Ningxia LBE may activate the cellular immune response. Although Xinjiang LBE has a relatively weaker antioxidant capacity than Ningxia-derived Lycium barbarum extract, it has a milder effect without alerting the cellular immune response. This study compared the bioactivity of Lycium barbarum extracts with different origins and extraction methods. It may provide a fast in vitro evaluation way for the biosafety and the bio-effectiveness of traditional Chinese medicine.