Hypoglycaemic activity of Mathurameha, a Thai traditional herbal formula aqueous extract, and its effect on biochemical profiles of streptozotocin-nicotinamide-induced diabetic rats.

BACKGROUND: The Thai traditional herbal formula-Mathurameha, consisting of 26 medicinal plants, has been used as an alternative and complementary medicine for diabetes treatment in Wangnamyen Hospital, Thailand. To provide scientific evidences on the efficacy and safety of this herbal formula, in vivo hypoglycaemic activity, effect on serum biochemical profiles and acute toxicity were investigated. METHODS: Experimental type 2 diabetes was induced in male Sprague-Dawley rats by intraperitoneal injection of nicotinamide 15 min prior to intravenous injection of streptozotocin. The most effective extract from the oral glucose tolerant test (OGTT) was administered daily via the oral route to diabetic rats for 2 weeks. Two-hour postprandial plasma glucose (2h-PPG) levels were measured on days 0, 7, and 14. Biochemical data were measured at the end of daily oral administration experiment. RESULTS: Aqueous extract of the herbal formula was the most potent extract for improving glucose tolerance of streptozotocin-nicotinamide-induced diabetic rats after single oral administration. After 2 weeks of daily oral administration, the aqueous extract showed a dose-dependent glucose lowering effect. At doses of 12.5, 25, and 50 mg/kg, the 2h-PPG level of diabetic rats decreased by 3.32%, 15.78%, and 17.94%, respectively. Most of the biochemical profiles of diabetic rats were improved, including the total cholesterol (TC), alkaline phosphatase (ALP), total protein, albumin, globulin, creatinine, and uric acid levels. The significantly increased triglyceride (TG) level observed in treated diabetic rats indicated a lack of a beneficial effect of the extract on lipid homeostasis. Nevertheless, there were no signs or symptoms of acute toxicity observed after oral administration of aqueous extract (5 g/kg) to both male and female rats. CONCLUSIONS: The results revealed that the herbal formula aqueous extract has hypoglycaemic activity, beneficial effects on biochemical profiles and a lack of acute toxicity. This study confirms the efficacy and safety of the Mathurameha herbal formula used for treating type 2 diabetes mellitus.

Effect of Siam weed extract and its bioactive component scutellarein tetramethyl ether on anti-inflammatory activity through NF-κB pathway.

ETHNOPHARMACOLOGICAL RELEVANCE: Siam weed (Chromolaena odorata (L.) King and Robinson) is a medicinal herb used for wound healing and inflammation-related diseases. AIM OF THE STUDY: In this study, we evaluated the molecular mechanism by which Siam weed extract (SWE) and its bioactive components, scutellarein tetramethyl ether (scu), stigmasterol, and isosakuranetin affect anti-inflammatory activity. MATERIALS AND METHODS: The expression of several inflammatory proteins in RAW 264.7 (murine) macrophages was assessed by Western blot and reverse transcription-polymerase chain reaction (RT-PCR). Biochemical assays including prostaglandin E2 (PGE2) and nitric-oxide (NO) quantification were performed. Luciferase promoter activity and immunocytochemistry of Nuclear factor-κB (NF-κB) were investigated. RESULTS: Cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) are critical pro-inflammatory proteins. The level of protein and mRNA expression of these enzymes induced by lipopolysaccharide (LPS) was dramatically suppressed by treatment with SWE, scu, or stigmasterol compounds in a dose-dependent manner. They also reduced PGE2 and NO release. We further analyzed the NF-κB pathway and found that the scu compound suppressed IκB kinase complex alpha/beta (IKKα/ß) and Inhibitory-kappa-B-alpha (IκBα), thereby suppressing COX-2 and iNOS expression. CONCLUSION: This is the first report of the anti-inflammatory molecular mechanism in SWE and/or its bioactive component scu, indicating alteration NF-κB pathway and further providing potential uses in the treatment of inflammatory-related diseases.

In vitro inhibitory effects of Moringa oleifera leaf extract and its major components on chemiluminescence and chemotactic activity of phagocytes.

The ethanol extract of Moringa oleifera Lam. leaves and its major constituents, crypto-chlorogenic acid, quercetin 3-O-glucoside and kaempferol 3-O-glucoside, were investigated on the respiratory burst of human whole blood and isolated human polymorphonuclear leukocytes (PMNs) using a luminol-based chemiluminescence assay. The chemotactic migration of PMNs was also investigated using the Boyden chamber technique. The ethanol extract demonstrated inhibitory activities on the oxidative burst and the chemotactic migration of PMNs. Quercetin 3-O-glucoside, crypto-chlorogenic acid, and kaempferol 3-O-glucoside, isolated from the extract, expressed relatively strong inhibitory activity on the oxidative burst of PMNs with IC50 values of 4.1, 6.7 and 7.0 microM, respectively, comparable with that of aspirin. They also demonstrated strong inhibition of chemotatic migration of PMNs with IC50 values of 9.5, 15.9 and 18.2 microM, respectively. The results suggest that M. oleifera leaves could modulate the immune response of human phagocytes, linking to its ethnopharmacological use as an anti-inflammatory agent. The immunomodulating activity of the plant was mainly due to its major components.

In vivo and in vitro hemostatic activity of Chromolaena odorata leaf extract.

CONTEXT: Chromolaena odorata (L.) R.M.King & H.Rob. (Asteraceae) or Siam weed has long been used to stop bleeding in Thailand and many countries. Only the aqueous leaf extract was investigated in in vivo and there have been conflicting results of in vitro hemostatic mechanisms of this plant. OBJECTIVE: The most appropriate C. odorata leaf extract that promoted the highest hemostatic activity and the hemostatic mechanisms of these plant extracts will be investigated. MATERIALS AND METHODS: The lyophilized aqueous leaf extract and alcoholic (50, 70, and 95% ethanol) extracts from the fresh and dried leaves were investigated both in vivo and in vitro. The bleeding time in male Wistar rats was measured to investigate the hemostatic effect. The hemostatic mechanisms were tested using in vitro platelet aggregation and blood coagulation tests in sheep plasma. RESULTS: All extracts displayed significantly reducing bleeding time (<2.5 min) in rats but did not induce platelet aggregation or blood clotting in the in vitro study. The in vitro blood clotting times of all extracts were >0.6 min. Ethanol extract (70%) from the dried leaves proved to be the extract producing the highest hemostatic activity in vivo with the bleeding time of 1.85 min. DISCUSSION AND CONCLUSION: The in vivo study with rats confirmed the significant ability of this plant extract to stop bleeding. However, the sufficient amount of calcium and active compounds which are aggregating and clotting agents to enhance blood coagulation and platelet aggregation in in vitro tests should be further studied.

Toxicity evaluation of sappan wood extract in rats.

BACKGROUND: The heartwood of Caesalpinia sappan L. or sappan wood has long been used in folk medicines to treat tuberculosis, diarrhea, dysentery, skin infections and anemia. OBJECTIVE: To study the acute and subacute toxicities of sappan wood extract in rats. MATERIAL AND METHOD: For studying acute toxicity, a single oral dose of 5000 mg/kg of sappan wood was administered to rats. Subacute toxicity was studied by the daily oral administration of the extract at the doses of 250, 500 and 1000 mg/kg body weight for consecutive 30 days. RESULTS: The extract of sappan wood (5000 mg/kg) showed no toxicity in terms of general behavior change, mortality, or change in gross appearance of internal organs. Subacute toxicity study showed no abnormalities in treatment groups as compared to the controls. Body and organ weights, hematological, blood chemical, necropsy, and histopathological parameter of all groups were similar. CONCLUSION: Sappan wood extract did not produce any acute or subacute toxicity in both female and male rats.

Aqueous extract of Abutilon indicum Sweet inhibits glucose absorption and stimulates insulin secretion in rodents.

The objective of this study was to evaluate the antidiabetic effects of the aqueous extract derived from the Thai Abutilon indicum Sweet plant and to explore its effects on intestinal glucose absorption and insulin secretion. The authors hypothesized that the plasma glucose level could be reduced through the inhibition of glucose absorption and/or the enhancement of insulin secretion. Administration of the extract (0.5 and 1 g/kg body weight) in an oral glucose tolerance test led to a significant reduction in plasma glucose levels in 30 minutes after the administration in moderately diabetic rats, as compared with untreated rats (P < .05), and this was at a faster rate than the use of an antidiabetic drug, glibenclamide. The inhibition of glucose absorption through the small intestine was investigated using an everted intestinal sac. The results showed that the extract at concentrations of 0.156 to 5 mg/mL caused a reduction of glucose absorption in a dose response manner. The maximum response was noted at a dose of 2.5 mg/mL. The promotion of the extract on insulin secretion was confirmed by incubating beta cell of pancreatic islets and INS-1E insulinoma cells with the extract at 1 to 1000 microg/mL. These observations suggest that the aqueous extract from the A indicum plant has antidiabetic properties, which inhibited glucose absorption and stimulated insulin secretion. Phytochemical screening also revealed that the extract contained alkaloids, flavonoids, tannins, glycosides, and saponins that could account for the observed pharmacologic effects of the plant extract.

Manganese-based complexes of radical scavengers as neuroprotective agents.

Manganese was incorporated in the structure of the selected antioxidants to mimic the superoxide dismutase (SOD) and to increase radical scavenging ability. Five manganese complexes (1-5) showed potent SOD activity in vitro with IC(50) of 1.18-1.84 microM and action against lipid peroxidation in vitro with IC(50) of 1.97-8.00 microM greater than their ligands and trolox. The manganese complexes were initially tested in vivo at 50 mg/kg for antagonistic activity on methamphetamine (MAP)-induced hypermotility resulting from dopamine release in the mice brain. Only manganese complexes of kojic acid (1) and 7-hydroxyflavone (3) exhibited the significant suppressions on MAP-induced hypermotility and did not significantly decrease the locomotor activity in normal condition. Manganese complex 3 also showed protective effects against learning and memory impairment in transient cerebral ischemic mice. These results supported the brain delivery and the role of manganese in SOD activity as well as in the modulation of brain neurotransmitters in the aberrant condition. Manganese complex 3 from 7-hydroxyflavone was the promising candidate for radical implicated neurodegenerative diseases.

Antifungal activity and local toxicity study of Alangium salviifolium subsp hexapetalum.

Alangium salviifolium subsp hexapetalum is a medicinal plant which has been traditionally used for tonic and treatment of hemorrhoid. This plant showed promising antimicrobial activity in our preliminary experiments, this study was, therefore, conducted to investigate its inhibitory effect against dermatomycotic organisms and its toxicity. The lyophilized powder extract (4.59%) of pulverized wood was tested for its inhibitory effect by agar disc diffusion test. The extract gave inhibitory zone diameters of 25.23 and 14.78 mm against 26 and 14 isolates of dermatophytes and Candida albicans, respectively. Ketoconazole, used as a reference antifungal agent, had inhibitory zone diameters of 33.15 and 27.93 mm against dermatophytes and C. albicans, respectively. There was no significant difference between the extract and ketoconazole in their inhibition against dermatophytes (p > 0.01), but their difference was significant against C. albicans (p < 0.01). Using Buehler' s method, different amounts of extract (3, 6, and 9 mg/inch2 gauze pad) were tested in five male New Zealand white rabbits. All tested amounts of extract did not induce dermatitis among those rabbits within 1 week. The results demonstrated the inhibitory effect of Alangium salviifolium subsp hexapetalum against fungi without any local toxicity; a tendency to further develop a herbal preparation for the treatment of some dermatomycotic infections.