title: Effect of the extract of the tamarind (Tamarindus indica) fruit on the complement system: studies in vitro and in hamsters submitted to a cholesterol-enriched diet.
abstract: This work evaluated a crude hydroalcoholic extract (ExT) from the pulp of the tamarind (Tamarindus indica) fruit as a source of compounds active on the complement system (CS) in vitro. ExT, previously characterized by other authors, had time and concentration dependent effects on the lytic activity of the CS. The activity of 0.8 mg/mL of the extract on the classical/lectin pathways (CP/LP) increased after 30 min of pre-incubation, while that of the alternative pathway (AP) decreased after 15 min at 1mg/mL. Since the CS is a mediator of inflammation, studies were also made in vivo, taking advantage of a model of hypercholesterolemia in hamsters to investigate the role of CS in the phase preceding the inflammatory process of atherosclerosis. Hamsters submitted to a diet rich in cholesterol showed increased lytic activity of the CP/LP and AP after 45 days. The activity levels of C2 and factor B components on respectively, classical/lectin and alternative pathways of the CS also increased. Early events cooperating to trigger the process of atherosclerotic lesions are not completely understood, and these alterations of complement may participate in these events. When treatment with a diet rich in cholesterol was associated to the furnishing of ExT, evaluation of complement components and complement lytic activity showed values similar to those of the controls, showing that treatment with ExT blocked the increase of complement activity caused by the cholesterol-rich diet. By itself, ExT had no effect on the complement system in vivo. ExT activity on the CS may be of interest for therapy and research purposes.
authors: Departamento de Física e Química, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Av. do Café, s/n, 14040-903, Ribeirão Preto, SP, Brazil.
authors: Ana Paula
authors: AP
authors: Landi Librandi
authors: Taís Nader
authors: TN
authors: Chrysóstomo
authors: Ana Elisa C S
authors: AE
authors: Azzolini
authors: Carem Gledes Vargas
authors: CG
authors: Recchia
authors: Sérgio Akira
authors: SA
authors: Uyemura
authors: Ana Isabel
authors: AI
authors: de Assis-Pandochi
mesh_terms: D000410:Alanine Transaminase / Q000097:blood; D000818:Animals; D001219:Aspartate Aminotransferases / Q000097:blood; D002784:Cholesterol / Q000097:blood; D003175:Complement C2 / Q000276:immunology* / Q000378:metabolism; D011415:Complement Factor B / Q000276:immunology* / Q000378:metabolism; D015941:Complement Hemolytic Activity Assay; D003170:Complement Pathway, Alternative / Q000187:drug effects*; D003171:Complement Pathway, Classical / Q000187:drug effects*; D006224:Cricetinae; D005638:Fruit / Q000737:chemistry; D006949:Hyperlipidemias / Q000188:drug therapy / Q000276:immunology*; D008297:Male; D008647:Mesocricetus; D010936:Plant Extracts / Q000494:pharmacology*; D018709:Statistics, Nonparametric; D029861:Tamarindus / Q000737:chemistry*; D014280:Triglycerides / Q000097:blood
chemical_list: D003175:Complement C2; D010936:Plant Extracts; D014280:Triglycerides; D002784:Cholesterol; D001219:Aspartate Aminotransferases; D000410:Alanine Transaminase; D011415:Complement Factor B