Journal of Ethnopharmacology 129 (2010) 23–33 Contents lists available at ScienceDirect Journal of Ethnopharmacology journal homepage: www.elsevier.com/locate/jethpharm Scoparia dulcis (SDF7) endowed with glucose uptake properties on L6 myotubes compared insulin Joo Ee Beh a,e , Jalifah Latip d,e , Mohd Puad Abdullah b,d,e , Amin Ismail c,e , Muhajir Hamid a,d,e,∗ a Department of Microbiology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia b Department of Cell and Molecular Biology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia c Department of Nutrition and Dietetics, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia d Institute of Bioscience, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia e School of Chemical Science and Food Technology, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor, Malaysia article info Article history: Received 30 September 2009 Received in revised form 31 December 2009 Accepted 8 February 2010 Available online 1 March 2010 Keywords: Scoparia dulcis Insulin Insulin resistance Glucose transport Glut 4 abstract Aim of the study: Insulin stimulates glucose uptake and promotes the translocation of glucose transporter 4 (Glut 4) to the plasma membrane on L6 myotubes. The aim of this study is to investigate affect of Scoparia dulcis Linn water extracts on glucose uptake activity and the Glut 4 translocation components (i.e., IRS-1, PI 3-kinase, PKB/Akt2, PKC and TC 10) in L6 myotubes compared to insulin. Materials and methods: Extract from TLC fraction-7 (SDF7) was used in this study. The L6 myotubes were treated by various concentrations of SDF7 (1 to 50 g/ml) and insulin (1 to 100 nM). The glucose uptake activities of L6 myotubes were evaluated using 2-Deoxy-D-glucose uptake assay in with or without fatty acid-induced medium. The Glut 4 translocation components in SDF7-treated L6 myotubes were detected using immunoblotting and quantified by densitometry compared to insulin. Plasma membrane lawn assay and glycogen colorimetry assay were carried out in SDF7- and insulin-treated L6 myotubes in this study. Results: Here, our data clearly shows that SDF7 possesses glucose uptake properties on L6 myotubes that are dose-dependent, time-dependent and plasma membrane Glut 4 expression-dependent. SDF7 suc- cessfully stimulates glucose uptake activity as potent as insulin at a maximum concentration of 50 g/ml at 480 min on L6 myotubes. Furthermore, SDF7 stimulates increased Glut 4 expression and translocation to plasma membranes at equivalent times. Even in the insulin resistance stage (free fatty acids-induced), SDF7-treated L6 myotubes were found to be more capable at glucose transport than insulin treatment. Conclusions: Thus, we suggested that Scoparia dulcis has the potential to be categorized as a hypoglycemic medicinal plant based on its good glucose transport properties. © 2010 Elsevier Ireland Ltd. All rights reserved. 1. Introduction Diabetes is the seventh leading cause of death worldwide, and currently, this disease involves a sum of $132 billion in treatment costs, which have been estimated to elevate to $192 billion by 2020 in the US (The National Institute of Diabetes and Digestive Kidney Diseases, 2008). According to WHO, 9.9% of the diabetic population is in Malaysia (2007) and this number is projected to be 12.3% by 2025 (Ministry of Health, Malaysia, 2007). Additionally, more than 90% of the diabetes reported cases were categorized as diabetes mellitus (type 2 diabetes), with severe complications such as hyper- glycemia, dyslipidemia, macrovascular and microvascular diseases ∗ Corresponding author at: Department of Microbiology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400, Serdang, Malaysia. Tel.: +60 3 8946 6707; fax: +60 3 8943 0913. E-mail address: muhajir@biotech.upm.edu.my (M. Hamid). and sexual dysfunctions (Williams, 1999). These metabolic diseases are delineated as being defective to sensitivity of peripheral tissues to insulin, also called insulin resistance (Reaven and Laws, 1999). Consequently, the enhancement of glucose uptake into muscle as the largest glucose disposal tissues is reduced, causing these severe complications of diabetes. Scoparia dulcis Linn or sweet broom weed, derived from fig- wort family (Scrophulariaceae), is an erect, annual, ubiquitous herb, which grows widely in European and Asian countries (Jain, 1985). In view of its popularity in ethnopharmacology, this plant had been extensively studied and widely reported upon by vari- ous researchers. This plant possesses significant hypoglycemic and insulin secretagogue activities (Pari and Latha, 2002). Scoparia dul- cis has also been reported to be endowed with antihypertensive (Chow et al., 1974), antitumor promoting (Nishino, 1993), antivi- ral (Hayashi, 1990) and antihyperalgesic (Ratnasooriya et al., 2003) properties. These biological activities are conceivably attributed to its active phytochemical constituents such as Scopadulcic Acids A 0378-8741/$ – see front matter © 2010 Elsevier Ireland Ltd. All rights reserved. doi:10.1016/j.jep.2010.02.009