ABSTRACT
The prevalence of metabolic disorders such as diabetes among population is of increasing concern worldwide. Sudan is a developing country, where several areas frequently depend on folk medicine. Several herbal preparations have been used in folklore practice in Sudan for the management of diabetes with claims asserting their hypoglycemic effect. Basic research relating to these plants are reviewed in this paper with the intention to highlight their therapeutic potential for the treatment of diabetes and promote their regular use in Sudan. Ethnobotanical information was obtained by an assessment of the available literature in electronic data bases with publications describing the medicinal plants used for the treatment of diabetes. In this review paper, different parts of 38 plant species, are described that are used in the Sudanese traditional medicine and belong to 35 genera and 23 families. Thirty three plants have been documented in scientific literature to possess in vivo antidiabetic activity and only one was ineffective in lowering blood glucose level, namely Striga hermonthica. Many of the plants in the study review have been studied in in vitro models (such as α-amylase or α-glucosidase inhibition) in an effort to explain some of their biomedical interaction. The role of isolated bioactive compounds like trigonelline and 3, 5-dicaffeoylquinic acid in diabetes management is also evaluated in the present review. Ten plants original from Sudan have been already used in clinical trials for the treatment of type 2 diabetes. This review provides useful information on the characterization of such herbal medicines that are utilized in the Sudanese traditional medicine for the control of metabolic syndromes such as diabetes
Subject(s)
Diabetes Mellitus/therapy , Ethnopharmacology , Medicine, African Traditional , Plants, Medicinal/pharmacology , SudanABSTRACT
Emerging evidence suggests that reactive oxygen (ROS) and nitrogen (RNS) species can contribute to diverse signalling pathways of inflammatory and tumour cells. Cucurbitacins are a group of highly oxygenated triterpenes. Many plants used in folk medicine to treat cancer have been found to contain cucurbitacins displaying potentially important anti-inflammatory actions. The current study was designed to investigate the anti-ROS and -RNS effects of cucurbitacin L 2-O-ß-glucoside (CLG) and the role of these signaling factors in the apoptogenic effects of CLG on human colon cancer cells (HT-29). This natural cucurbitacin was isolated purely from Citrullus lanatus var. citroides (Cucurbitaceae). The results revealed that CLG was cytotoxic to HT-29. CLG increased significantly (P < 0.05) RNA and protein levels of caspase-3 in HT-29 cells when verified using a colorimetric assay and realtime qPCR, respectively. The results showed that lipopolysaccharide/interferon-gamma (LPS/INF-γ) increased nitrous oxide (NO) production inR AW264.7macrophages, whereas N(G)-nitro-L-argininemethyl ester (L-NAME) and CLG curtailed it. This compound did not reveal any cytotoxicity on RAW264.7 macrophages and human normal liver cells (WRL-68) when tested using the MTT assay. Findings of ferric reducing antioxidant power (FRAP) and oxygen radical absorption capacity (ORAC) assays demonstrate the antioxidant properties of CLG. The apoptogenic property of CLG on HT-29 cells is thus related to inhibition of reactive nitrogen and oxygen reactive species and the triggering of caspase-3-regulated apoptosis.
ABSTRACT
The in vivo and in vitro mechanistic anti-inflammatory actions of cucurbitacin E (CE) (Citrullus lanatus var. citroides) were examined. The results showed that LPS/INF-γ increased NO production in RAW264.7 macrophages, whereas L-NAME and CE curtailed it. CE did not reveal any cytotoxicity on RAW264.7 and WRL-68 cells. CE inhibited both COX enzymes with more selectivity toward COX-2. Intraperitoneal injection of CE significantly suppressed carrageenan-induced rat's paw edema. ORAC and FRAP assays showed that CE is not a potent ROS scavenger. It could be concluded that CE is potentially useful in treating inflammation through the inhibition of COX and RNS but not ROS.
