ABSTRACT
Moringa oleifera Lam. (MO) has been reported to harbor anti-oxidation and anti-inflammatory activity and useful in the treatment of inflammatory diseases. However, despite these findings there has been little work done on the effects of MO on immune cellular function. Since macrophages, TNF and related cytokines play an important pathophysiologic role in lung damage induced by cigarette smoke, we examined the effects of MO on cigarette smoke extract (CSE)-induced cytokine production by human macrophages. An ethyl acetate fraction of MO (MOEF) was prepared from fresh leaves extract of Moringa and shown to consist of high levels of phenolic and antioxidant activities. Human monocyte derived macrophages (MDM) pre-treated with varying concentrations of MOEF showed decreased production of TNF, IL-6 and IL-8 in response to both LPS and CSE. The decrease was evident at both cytokine protein and mRNA levels. Furthermore, the extract inhibited the expression of RelA, a gene implicated in the NF-κB p65 signaling in inflammation. The findings highlight the ability of MOEF to inhibit cytokines (IL-8) which promote the infiltration of neutrophils into the lungs and others (TNF, IL-6) which mediate tissue disease and damage.
Subject(s)
Interleukin-6/metabolism , Interleukin-8/metabolism , Moringa oleifera/chemistry , Smoke/adverse effects , Tumor Necrosis Factor-alpha/metabolism , Acetates/chemistry , Gene Expression , Humans , Inflammation/metabolism , Lipopolysaccharides/adverse effects , Lung/drug effects , Lung/physiopathology , Lung Diseases/chemically induced , Lung Diseases/drug therapy , Macrophages/metabolism , NF-kappa B/metabolism , Neutrophils/drug effects , Neutrophils/metabolism , Plant Exudates/pharmacology , Signal Transduction , Nicotiana/adverse effectsABSTRACT
UNLABELLED: Moringa oleifera is used in Thai traditional medicine as cardiotonic. Recent studies demonstrated its hypocholesterolaemic effect. However, to be clinically useful, more scientific data are needed. AIM OF THE STUDY: We investigated the antioxidant, hypolipidaemic and antiatherosclerotic activities of Moringa oleifera leaf extract. MATERIALS AND METHODS: Scavenging activity of the extract on 1,1-diphenyl-2-picrylhydrazyl radicals (DPPH), and the inhibitory effect on Cu(2+)-induced low-density lipoprotein (LDL) oxidation were determined in in vitro experiment. The effects of the extract on cholesterol levels, conjugated diene (CD) and thiobarbituric acid reactive substances (TBARS) and plaque formations in cholesterol-fed rabbits were investigated. RESULTS: We found that in scavenging DPPH radicals the extract and Trolox had IC(50) of 78.15+/-0.92 and 2.14+/-0.12microg/ml, respectively. The extract significantly (P<0.05) prolonged the lag-time of CD formation and inhibited TBARS formation in both in vitro and ex vivo experiments in a dose-dependent manner. In hypercholesterol-fed rabbits, at 12 weeks of treatment, it significantly (P<0.05) lowered the cholesterol levels and reduced the atherosclerotic plaque formation to about 50 and 86%, respectively. These effects were at degrees comparable to those of simvastatin. CONCLUSIONS: The results indicate that this plant possesses antioxidant, hypolipidaemic and antiatherosclerotic activities and has therapeutic potential for the prevention of cardiovascular diseases.
