Anti-inflammatory and Cytoprotective Effect of Clinacanthus nutans Leaf But Not Stem Extracts on 7-Ketocholesterol Induced Brain Endothelial Cell Injury

AbstractClinacanthus nutans (Lindau) (C. nutans) has diverse uses in traditional herbal medicine for treating skin rashes, insect and snake bites, lesions caused by herpes simplex virus, diabetes mellitus and gout in Singapore, Malaysia, Indonesia, Thailand and China. We previously showed thatC. nutans has the ability to modulate the induction of cytosolic phospholipase A2 (cPLA2) expression in SH-SY5Y cells through the inhibition of histone deacetylases (HDACs). In the current study, we elucidated the effect ofC. nutans on the hCMEC/D3 human brain endothelial cell line. Endothelial cells are exposed to high levels of the cholesterol oxidation product, 7-ketocholesterol (7KC), in patients with cardiovascular disease and diabetes, and this process is thought to mediate pathological inflammation. 7KC induced a dose-dependent loss of hCMEC/D3 cell viability, and such damage was significantly inhibited byC. nutans leaf extracts but not stem extracts. 7KC also induced a marked increase in mRNA expression of pro-inflammatory cytokines, IL-1 β IL-6, IL-8, TNF-α and cyclooxygenase-2 (COX-2) in brain endothelial cells, and these increases were significantly inhibited byC. nutans leaf but not stem extracts. HPLC analyses showed that leaf extracts have a markedly different chemical profile compared to stem extracts, which might explain their different effects in counteracting 7KC-induced inflammation. Further study is necessary to identify the putative phytochemicals inC. nutans leave...
Source: NeuroMolecular Medicine - Category: Neurology Source Type: research