In Vitro evaluation of protective effects of phillyrea latifolia extracts against oxidative stress and inflammation on co-cultured neuronal cell line SH-SY5Y

Neuroinflammation has a vital role in the pathogenesis of numerous neurodegenerative and neurobehavioural disorders which could be a major health concern affecting a major population. Given that the current therapeutic approaches do not yet provide the desired level of efficacy therefore herbal supplements are thoroughly researched as potential therapeutic options. The goal of current study is to comprehensively evaluate every in vitro protective outcomes of P. latifolia extracts against neuroinflammation, in terms of their antioxidant activities, protective effects against inflammation and oxidative stress. The total amount of proanthocyanidin, flavonoids, and phenolics, further as DPPH, FRAP and CUPRAC assays were conducted. The protective role against inflammation was evaluated by in vitro nitrite assay in LPS-effected RAW 264.7 murine macrophage cells and IL-6 releasing and PGE2 production inhibition assays likewise as determination of TNF-α. To support as an in vitro neuroinflammation model; co-culture assay was also performed. Both extracts significantly decreased the nitrite levels at 1 mg/mL concentration. It had been also demonstrated that the P. latifolia extracts were able to significantly lower the levels of TNF-α, IL-6, and PGE2. The analyses of oxidative stress parameters within the cell lysates revealed that the P. latifolia extracts were ready to enhance GSH, CAT, SOD and reduce MDA levels thus relieving the cells from increased oxidative stress in both SH-SY5Y and RAW 264.7 cell lines. Furthermore, in transwell co-culture assay, the hydroalcoholic extract decreased inflammation-induced cell death significantly at 48 and 72 hours post application. In conclusion, our results suggest that P. latifolia extracts could have implications for the management of neuroinflammation as herbal remedy.