Centella asiatica modulates cancer cachexia associated inflammatory cytokines and cell death in leukaemic THP-1 cells and peripheral blood mononuclear cells (PBMC’s)

BACKGROUND Cancer cachexia is associated with increased pro-inflammatory cytokine levels. Centella asiatica (C. asiatica) possesses antioxidant, anti-inflammatory and anti-tumour potential. We investigated the modulation of antioxidants, cytokines and cell death by C. asiatica ethanolic leaf extract (CLE) in leukaemic THP-1 cells and normal peripheral blood mononuclear cells (PBMC's). METHODS Cytotoxcity of CLE was determined at 24 and 72 h (h). Oxidant scavenging activity of CLE was evaluated using the 2, 2-diphenyl-1 picrylhydrazyl (DPPH) assay. Glutathione (GSH) levels, caspase (-8, -9, -3/7) activities and adenosine triphosphate (ATP) levels (Luminometry) were then assayed. The levels of tumour necrosis factor-α (TNF-α), interleukin (IL)-6, IL-1β and IL-10 were also assessed using enzyme-linked immunosorbant assay. RESULTS CLE decreased PBMC viability between 33.25-74.55% (24 h: 0.2-0.8 mg/ml CLE and 72 h: 0.4-0.8 mg/ml CLE) and THP-1 viability by 28.404% (72 h: 0.8 mg/ml CLE) (p < 0.0001). Oxidant scavenging activity was increased by CLE (0.05-0.8 mg/ml) (p < 0.0001). PBMC TNF-α and IL-10 levels were decreased by CLE (0.05-0.8 mg/ml) (p < 0.0001). However, PBMC IL-6 and IL-1β concentrations were increased at 0.05-0.2 mg/ml CLE but decreased at 0.4 mg/ml CLE (p < 0.0001). In THP-1 cells, CLE (0.2-0.8 mg/ml) decreased IL-1β and IL-6 whereas increased IL-10 levels (p < 0.0001). In both cell lines, CLE (0.05-0.2 mg/ml, 24 and 72 h) increased GSH concentrations (p < 0.0001). At 24 h, caspase (-9, -3/7) activities was increased by CLE (0.05-0.8 mg/ml) in PBMC's whereas decreased by CLE (0.2-0.4 mg/ml) in THP-1 cells (p < 0.0001). At 72 h, CLE (0.05-0.8 mg/ml) decreased caspase (-9, -3/7) activities and ATP levels in both cell lines (p < 0.0001). CONCLUSION In PBMC's and THP-1 cells, CLE proved to effectively modulate antioxidant activity, inflammatory cytokines and cell death. In THP-1 cells, CLE decreased pro-inflammatory cytokine levels whereas it increased anti-inflammatory cytokine levels which may alleviate cancer cachexia.