The Moringa Oleifera Lam. Leaf Extract Exerts Its Inhibitory Effect Against Periodontitis By Inhibiting The P38 MAPK Pathway

Objective:The effect and mechanism of water extract of Moringa leaf on experimental periodontitis were studied in vitro and in vivo.Methods:1.The water extraction method was used to extract the Moringa leaf and determine their nutritional components and contents.2.We established the periodontitis model of rats,and randomly divided them into three groups: disease control group(control),low dose experimental group(0.5g / kg BW),high dose experimental group(1g / kg BW),10 rats in each group,and administrated by gavage every other day after modeling.Rats were killed four weeks after gavage every day,and hematoxylin eosin(HE)staining method was used to observe the toxic effects of drugs on organs and the infiltration of inflammatory cells in periodontal tissues;Micro-CT was used to evaluate the absorption of alveolar bone;ELISA method was used to detect the expression of OPG / RANKL and related inflammatory factors in serum of rats.3.Mouse macrophage line RAW264.7 was cultured and treated with water extract of Moringa leaf;cell proliferation activity was detected by CCK8 method;add 1μg/ml Pg.LPS stimulate cells,and randomly divided them into four groups: control group(control),experimental group(200μg/ml,400μg/ml,800μg/ml);after 24 hours,relative expression of OPG / RANKL and inflammatory factors IL-1β,IL-6,TNF-α,IL-1Ra and IL-10 in cells was detected by real-time quantitative PCR;expression levels of p38,p-p38 and OPG / RANKL were detected by Western blot.Results:1.The content of polyphenol and flavone in the water extract of Moringa leaves was high,and it showed strong antioxidant activity.The toxicity of the extracts was slight in vivo and it had no toxic effect on macrophages at low concentration.2.Osteoprotective effect: After the treatment of drugs,the alveolar bone resorption was reduced.The expression level of OPG / RANKL in vitro and in vivo showed bone resorption inhibition.3.Anti-inflammatory effect: After the treatment of drugs,the infiltration of inflammatory cells in periodontal tissue were significantly reduced.In serum and cells of rats,the expression levels of pro-inflammatory factors IL-1 β,IL-6,TNF-α decreased,and the expression levels of anti-inflammatory factors IL-1Ra,IL-10 increased.4.After drug treatment,the ratio of p-p38 / p38 protein expression decreased,and the ratio of OPG / RANKL protein expression increased.Conclusion:In a certain concentration range,the water extract of the leaves of Moringa oleracea has no side effects in vivo and in vitro,and has a certain biological safety.The water extract of Moringa leaf can inhibit the progression of experimental periodontitis by inhibiting p38 MAPK signal pathway and increasing OPG / RANKL ratio.