Hypoglycemic and hypolipidemic effect of leaves from Syzygium cumini (L.) Skeels, Myrtaceae. in diabetic rats

Abstract

RESUMO: "Efeito hipoglicêmico e hipolipidêmico das folhas de Syzygium cumini Lam. em ratos diabeticos". Na região de Criciúma-SC, as folhas de Syzygium cumini (L.) Skeels, Myrtaceae, conhecida popularmente como jambolão, são utilizadas para diminuir níveis de glicose plasmática em pessoas diabéticas. Dentro deste contexto o presente trabalho teve o interesse de avaliar o efeito hipoglicêmico e hipolipidêmico do extrato bruto hidroalcoólico (EBH) das folhas de S. cumini (125, 250 e 500 mg/kg). Para tal os animais foram divididos em três grupos para o efeito hipoglicêmico: ratos normais, ratos normais submetidos a curva de glicose (hiperglicêmicos) e ratos diabéticos induzidos com aloxana. O efeito hipolipidêmico foi avaliado em animais diabéticos induzidos por aloxana. O efeito hipoglicêmico foi comparado com glibenclamida. O tratamento agudo com EBH de S. cumini causou uma diminuição estatisticamente significativa na glicose sanguínea em animais normais que foram submetidos à cura de glicose (250 mg/kg), e sobre os níveis de glicose (125 e 250 mg/kg), triglicerídeo (125 e 500 mg/kg) e colesterol (125 mg/kg) em animais diabéticos. Nenhuma das doses testadas apresentou efeito em animais normais. Dentro deste contexto pode-se sugerir que o EBH das folhas de S. cumini pode ser uma alternativa terapêutica no tratamento alternativo ou complementar na diabete, uma vez que apresentou atividade hipoglicêmica e hipolipidêmica em animais diabéticos.Unitermos: Syzygium cumini, Myrtaceae, diabete, hipoglicêmico, hipolipidêmico, plantas medicinais.ABSTRACT: Ethanolic crude extract (ECE) of leaves from Syzygium cumini (L.) Skeels, Myrtaceae was screened for its hypoglycemic and hypolipidemic activity (125, 250 and 500 mg/kg v.o.). Rats were divided into three groups for the evaluation of the hypoglycemic effect: normal rats, rats with alloxan-induced diabetes and hyperglycemic normal rats. Hypolipidemia was evaluated in rats with alloxan-induced diabetes. The antihyperglycemic activity was compared to treatment with glibenclamide, an oral hypoglycemic agent. The acute treatment with S. cumini ECE caused a significant decrease in the blood glucose in hyperglycemic normal rats (250 mg/kg), and in glucose (125 and 250 mg/kg), triglyceride (125 and 500 mg/kg) and cholesterol (125 mg/kg) levels of diabetic rats, but no effect was observed in the normal treated rats. Syzygium cumini leaves are a good candidate for alternative and/or complementary medicine in the management of diabetes mellitus, since they showed hypoglycemic activity in addition to a hypolipidemic action in diabetic animals.

Plants used as antidiabetics in popular medicine in Rio Grande do Sul, southern Brazil

“…Popular names such as "insulin" and "vegetal insulin" were repeatedly mentioned, for four species of two different families: Aspilia montevidensis and Sphagneticola trilobata (Asteraceae); and Tea, flower dust Garlet and Irgang (2001) Antihyperglycemic activity of the extract by simulation of secretion via pancreatic islets (Hsu et al, 2009); butanol fraction showed potential to prevent Th1-mediated diabetes but promoted Th2-mediated inflammation (Chang et al, 2004(Chang et al, , 2005; water ethanol extracts reduced the hyperglycemia in mildly diabetic mice (Alarcon-Aguilar et al, 2002); The aqueous alcohol extract of the aerial parts showed hypoglicemic activity attributed to polyacetylenic glucosides (Ubillas et al, 2000) Whole (2001) Antioxidant activity related to antidiabetic activity (Souza et al, 2009;Khalil et al, 2008); kaempferol-3-neohesperidoside showed mimetic effect like insulin (Cazarolli et al, 2009b); absence of antidiabetic activity (Volpato et al, 2008); antidiabetic effect attributed to kaempferitrin (Jorge et al, 2004); for review (Cechinel, 2009) (Schoenfelder et al, 2010); aqueous leaf extracts showed hypoglicemic activity in hyperglycemic patients (Bopp et al, 2009); hypoglicemic activity attributed to cuminoside from seeds (Farswan et al, 2009); hypoglycemic activity of mycaminose extracted from seed (Kumar et al, 2008); ethanolic extract of seeds showed hypoglicemic activity in rats (Singh and Gupta, 2007) absence of antihyperglycemic effect of tea and extracts prepared from leaves in normal rats, rats with streptozotocin-induced diabetes, normal volunteers and patients with diabetes ; in vitro glucose uptake activity (Anandharajan et al, 2006); aqueous extract decreased the blood glucose in normal and diabetic rats (Rafiullah et al, 2006); dried bark extract showed antihyperglycemic and hypoglicemic activities (Villaseñor and Lamadrid, 2006); tea prepared from leaves of S. cumini do not showed hypoglycemic effect in patients with type 2 diabetes mellitus ; extract do not reduced the glycemia in diabetic mice the tea and extracts prepared from leaves are pharmacologically inert in diabetic patients (Teixeira et al, 2004); the treatment with tea prepared from leaves did not produce any antihyperglycemic effect in young volunteers neither the crude extract prepared from leaves in diabetic or non-diabetic rats (T...…”

Bioassay-guided fractionation and identification of α-amylase inhibitors from Syzygium cumini leaves

“…Bark, fruits, seeds and leaves of S. cumini are frequently used to treat diabetes in many parts of the world including Sri Lanka for centuries (Schoenfelder et al. 2010 ; Ediriweera & Ratnasooriya 2009 ). However, scientific data are lacking on the antidiabetic effects of SC leaves.…”

“…Ethanol extract of SC leaves was found to cause a decrease in the blood glucose, triglycerides and cholesterol concentrations when given to alloxan-induced diabetic rats (Schoenfelder et al. 2010 ). In another study, ethanol extract of SC leaves exhibited α-glucosidase inhibitory activity with an IC 50 of 17.4 μg/mL (Saraswaty 2012 ).…”

A fitoterapia como uma alternativa terapêutica complementar para pacientes com Diabetes Mellitus no Brasil

“…Figueiredo e Modesto-Filho (24) 2008 Diabéticos tipo 2 30-65 anos João Pessoa-PB Schoenfelder et.al., (22) 2008 Ratos normais e diabéticos Criciúma-SC Feijó et al, (20) 2012 Idosos diabéticos que afirmaram fazerem o uso de plantas medicinais…”