ABSTRACT
Cerebrovascular accidents and coronary artery disease are the leading causes of cardiovascular mortalities in Brazil and high levels of LDL cholesterol are one of the main risk factors. In this context, several plant extracts and natural substances have shown promise as cholesterol-lowering. The objective of this study was to evaluate the potential of the hydroalcoholic extract of the fruit of H. dulcis and of dihydromyricetin in cholesterol reduction in hypercholesterolemic rats. Forty-two Wistar male rats were distributed into seven groups of six animals that received diets supplemented with 1% cholesterol and 0.3% cholic acid, with the exception of the control group, which received conventional diets. Animals were treated with oral suspensions containing: atorvastatin 1.0 mg/kg; H. dulcis extract at 50.0 and 100.0 mg/kg and dihydromyricetin at 25.0 and 50.0 mg/kg vehicle (control group). The following biochemical markers were evaluated; total cholesterol, HDL-C, LDL-C, triglycerides, AST, ALT, and alkaline phosphatase. The hypercholesterolemic diet was effective in inducing hypercholesterolemia, increasing total cholesterol by 112.7% relative to the control group. The treatments with two doses of the extract proved to be promising hypocholesterolemic agents, as they were able to substantially reduce total cholesterol and LDL-C, without significantly altering triglycerides, hepatic transaminases, and alkaline phosphatase, thereby encouraging the studies with the plant H. dulcis. The groups treated with the flavonoid dihydromyricetin, although they showed a significant reduction in total cholesterol and LDL-C, and found increases in triglycerides and hepatic transaminases, which is unwanted in the context of hypercholesterolaemia.
No Brasil, o acidente vascular cerebral e a doença arterial coronariana constituem as principais causas de mortalidade cardiovascular, sendo os altos níveis de colesterol LDL um dos principais fatores de risco. Nesse contexto, diversos extratos vegetais e substâncias naturais isoladas têm se mostrado promissoras como hipocolesterolemiantes. O objetivo do trabalho foi avaliar o potencial do extrato hidroalcoólico dos frutos de Hovenia dulcis e do flavonóide diidromiricetina na redução do colesterol em ratos hipercolesterolêmicos. Quarenta e dois ratos Wistar machos, foram distribuídos em 7 grupos de 6 animais, que receberam dieta suplementada com 1% de colesterol e 0,3% de ácido cólico, à exceção do grupo controle, que recebeu ração convencional. Posteriormente, os animais foram tratados com suspensões orais contendo: atorvastatina 1,0 mg/kg; extrato de H. dulcis de 50,0 e 100,0 mg/kg; diidromiricetina de 25,0 e 50,0 mg/kg e veículo (grupo controle). Avaliaram-se os parâmetros bioquímicos: colesterol total, HDL-C, LDL-C, triglicérides, AST, ALT e fosfatase alcalina. A dieta hipercolesterolêmica foi efetiva na indução da hipercolesterolemia, aumentando o colesterol total em 112,7% em relação ao controle. Os tratamentos com as duas doses do extrato mostraram-se promissores como agentes hipocolesterolemiantes, já que foram capazes de reduzir substancialmente o colesterol total e LDL-C, sem alterar significativamente triglicérides, as transaminases hepáticas e a fosfatase alcalina, incentivando, assim, a continuidade de estudos com a planta H. dulcis. Já os grupos tratados com o flavonóide diidromiricetina, apesar de apresentarem redução significativa do colesterol total e de LDL-C, apresentaram elevações nos triglicérides e nos parâmetros hepáticos, resultado indesejável no âmbito das hipercolesterolemias.