Antidiabetic Properties and Mechanism of Action of Orthosiphon stamineus Benth Bioactive Sub-fraction in Streptozotocin-induced Diabetic Rats

Abstract

Orthosiphon stamineus is a popular folk medicine widely used to treat many diseases including diabetes. Previous studies have shown that the sub-fraction of chloroform extract was able to inhibit the rise of blood glucose levels in a glucose tolerance test. This study was carried out to evaluate the chronic effect and possible mechanism of action of the bioactive chloroform sub-fraction of O. stamineus using streptozotocin-induced diabetic rats and in vitro methods. Administration of the chloroform extract sub-fraction 2 (Cƒ2-b) at a dose of 1 g/kg twice daily on diabetic rats for 14 days showed a significant lowering (p < 0.05) of the final blood glucose level compared to the pretreatment level. However, there were no significant differences in the plasma insulin levels post-treatment compared to the pretreatment levels for all doses of Cƒ2-b. Conversely, Cƒ2-b at a concentration of 2 mg/mL significantly increased (p < 0.001) the glucose uptake by the rat diaphragm muscle. The increase in glucose uptake was also shown when the muscle was incubated in a solution containing 1 IU/mL of insulin or 1 mg/mL of metformin. Furthermore, the effect of this sub-fraction on glucose absorption in the everted rat jejunum showed that Cƒ2-b at concentrations of 0.5 mg/mL, 1 mg/mL and, 2 mg/mL significantly reduced the glucose absorption of the jejunum (p < 0.05-0.001). Similarly, the absorption of glucose was also inhibited by 1 mg/mL and 2 mg/mL of metformin (p < 0.001). These results suggest that the effect of Cƒ2-b may be due to extra-pancreatic mechanisms. There was no evidence that the plant extract stimulated the release of insulin in order to lower the blood glucose level.

Extraction and Microencapsulation of Polyphenols from Orthosiphon Stamineus Leaves

“…The UPLC method developed for the first time by Pang et al [10] is capable of a fast and accurate qualitative and quantitative analysis of polyphenols from O. stamineus extract. The analysis time is less than 7 minutes, as shown in Figure 1, which is about three times faster than those of the other reported methods [3,17]. The UPLC chromatogram shown in Figure 1 suggests that the presence of maltodextrin or whey protein does not affect polyphenol separation in the HSS T3 column.…”

“…O. stamineus is traditionally used in Malaysia for treatment of bladder inflammation, eruptive fever, oedema, hepatitis, jaundice, hypertension, diabetes mellitus, gout, rheumatism, diuretic problems and influenza [1]. Previous studies revealed that extract of O. stamineus contained many medically useful bioactive compounds such as terpenoids, polyphenols and sterols that provide diuretic [2], antidiabetic [3], antiangiogenic and antiproliferative properties [4]. O. stamineus contains many useful active components such as rosmarinic acid, sinensetin and eupatorin, which can be recovered through the extraction process.…”

Embracing new agriculture commodity through integration of Java Tea as high Value Herbal crops in solar PV farms

“…The healing power of Java Tea plant is because of its great chemical contents (Engku Hasmah, Ahmad Tarmizi, Noor Ismawaty and Abdul Ghani, 2012) and sufficient literature on this remarkable plant claims that it can be used to cure chronic diseases such as Diabetics, High Blood Pressure, Blood Circulation Disorder, Gout and Rheumatism and Kidney Stones (Cicero et al, 2012;Dole ckov a et al, 2012;Mohamed et al, 2013).…”

Hexane Extract ofOrthosiphon stamineusInduces Insulin Expression and Prevents Glucotoxicity in INS-1 Cells

“…Tea made from the leaves and roots of this plant is believed to ameliorate various pathologic conditions, such as rheumatic arthritis, diabetes, hypertension, tonsillitis, epilepsy, menstrual disorders, gonorrhea, syphilis, renal calculus, and urinary lithiasis [12,13]. Recently, other beneficial effects were reported, including antidiabetic, anti-inflammatory, antiproliferative, and antiangiogenic activities [14,15,16,17,18]. Moreover, several previous reports have provided evidence for the metabolic effects of OS.…”

“…Furthermore, Son et al [19] reported that crude OS extract elevates plasma levels of insulin in rats, while Choi et al [20] demonstrated the leptin stimulating effect of OS both in vitro and in vivo . Mohamed et al [18] also showed that OS exerts antidiabetic effects in streptozotocin (STZ)-diabetic rats. However, we still do not know whether OS stimulates insulin production or protects β-cell from glucotoxicity.…”