Centella asiatica enhances neurogenesis and protects neuronal cells against H2O2-induced oxidative injury

Abstract

Traditionally, Centella asiatica leaf extracts are used to treat neurodegenerative diseases in India. Centella asiatica is reportedly used to enhance memory and treat dementia, but its promoting effect on neural stem cell differentiation has not been studied yet. In the present study, we investigated whether or not Centella asiatica leaf extracts act on neuronal precursor cells and neuronal cell lines to induce neuronal differentiation, neurite outgrowth, and neuroprotection. The neurogenesis-promoting potential of Centella asiatica leaf extracts was determined by differentiation assay on neural stem cells isolated from mouse embryos and PC12 cell lines. To understand the contribution of specific neural cell types towards increase after Centella asiatica treatment, neural stem cells were differentiated into various neural subtypes and checked by Western blotting using neural cell lineage-specific antibody markers. Neuroprotective activity of Centella asiatica was analyzed in PC12 cells exposed to 100 μM of H2O2. Cell growth was analyzed by MTT assay while cell death was analyzed by Western blotting detection of apoptosis-related proteins. Cells treated with Centella asiatica had significantly longer primary and secondary neurites as well as a higher number of neurites per cell compared to control cells. Expression levels of TUBBIII, TH, NF, and BDNF increased upon Centella asiatica treatment, suggesting that Centella asiatica has a neurogenesis-promoting effect. Centella asiatica also inhibited oxidative stress-induced neural cell damage through regulation of apoptosis- and cell cycle-related proteins. Thus, leaf extracts of Centella asiatica might promote neurogenesis, neuroregeneration, and neuroprotection in the context of neurodegenerative diseases.