Herbal formulation, DIA-2 and Rosiglitazone ameliorates hyperglycemia and hepatic steatosis in type 2 diabetic rats.

DIA-2 is a herbal mixture containing standardized extract of Allium sativum and Lagerstroemia speciosa. Recently we have reported the anti-diabetic effect of DIA-2 in high fat diet (HFD) and streptozotocin (STZ) induced type 2 diabetic (T2D) rats. The purpose of this study was to investigate and compare the effects of DIA-2 with Rosiglitazone (RG) on plasma biomarkers of hepatocellular injury, liver carbohydrate metabolizing enzymes, glycogen content, oxidant/antioxidant status and histopathological changes in T2D rats. ALT and ALP levels were significantly decreased after DIA-2 and RG treatment compared to T2D rats. Total protein and albumin remained unaltered in all the groups. Significant decrease in AST levels were observed after DIA-2 (125 mg/kg) and RG treatment. Hepatic hexokinase activity was significantly increased after RG and DIA-2 treatment and fructose-1, 6-bisphosphatase activity were inversely correlated with hexokinase activity. Hepatic gucose-6-phosphatase activity was significantly (p < 0.05) reduced after DIA-2 (62.5 mg/kg) and RG treatment. Lipid peroxides levels was significantly decreased in the liver of DIA-2 (62.5; p < 0.01 & 125 mg/kg; p < 0.05) treated animals. Hepatic glycogen content (p < 0.05) and antioxidant enzymes [SOD (p < 0.01; 62.5 mg/kg); GPx and GSH (125 mg/kg; p < 0.01)] were significantly increased after DIA-2 treatment. RG treatment on hepatic glycogen, GPx (p < 0.01) and SOD, GSH (p < 0.05) levels were significant when compared to T2D rats. These biochemical parameters were also correlated with histopathological evaluation. The above findings revealed that administration of DIA-2 could ameliorate the biochemical and histopathological changes in liver of T2D rats indicating the protective role of DIA-2 against HFD/STZ induced diabetes. In addition, DIA-2 and RG treatment resulted in amelioration of hepatic steatosis in T2D rats.

DIA-2, a polyherbal formulation ameliorates hyperglycemia and protein-oxidation without increasing the body weight in type II diabetic rats.

BACKGROUND: The dried bulbs of Allium sativum (Garlic) and leaves of Lagerstroemia speciosa (Banaba) are used as medicinal food for the treatment of diabetes and other ailments. AIM: The present study was undertaken to ascertain whether the combination of both garlic and banaba extract produces synergistic therapeutic effect in diabetic state. METHODS: In the in vitro studies, the effect of standardized aqueous extract of Allium sativum (ASE), methanolic extract of Lagerstroemia speciosa (LSE) and their mixture (1:1 ratio), DIA-2 on insulin stimulated glucose uptake in 3T3-L1 cells, erythrocyte sorbitol accumulation and protein glycation were evaluated. Impetus from the in vitro findings triggered to screen the anti-diabetic potential of DIA-2 in rat model of type II diabetes and associated oxidative stress. In the in vivo studies, acute oral toxicity of DIA-2 was determined following OECD-423 guidelines in female rats. Anti-diabetic activity of DIA-2 was investigated in high fat diet/low dose streptozotocin induced type II diabetes at four dose levels (62.5, 125, 250 and 500 mg/kg b.w) in rats. RESULTS: Combination of ASE and LSE produced synergistic and a dose dependent increase in glucose uptake in 3T3 adipocyte cell lines when compared to the individual extracts. A similar effect was observed in the inhibition of sorbitol accumulation and protein glycation tests. DIA-2 restored the glucose and lipid level near to normal level without gain in body weight which is the most commonly encountered side effect with the use of conventional antidiabetic agents, particularly insulin, insulin secretagogues, sulfonylureas and thiazolidinediones. DIA-2 also decreased hepatic protein carbonyl content levels significantly in the diabetic rats. CONCLUSIONS: The study concluded that DIA-2 posses potent anti-diabetic activity and anti-oxidant effects.  

In vitro cytotoxic, antioxidative and alpha-glucosidase inhibitory potential of a herbal mixture comprised of Allium sativum and Lagerstroemia speciosa.

BACKGROUND: Hyperglycemia induced over production of free radicals in the mitochondrial electron transport chain is now considered as one of the central mechanisms in the pathogenesis of diabetic complications. Allium sativum and Lagerstroemia speciosa contains active principles possessing anti-diabetic and antioxidant properties. This study is aimed at evaluating the evidence that supports this traditional claim and investigates the possible synergistic effect on these herbs when given as a herbal mixture in vitro. AIM: The present study investigates the cytotoxic, antioxidant and a-glucosidase inhibitory potential of Allium sativum (ASE), Lagerstroemia speciosa (LSE) and their combinations using in vitro methods. MATERIALS AND METHODS: The total phenol, total flavonoid and total tannin content were determined in ASE and LSE. The cytotoxic effects of ASE, LSE and their combination in the ratio of 1:2, 1:1 w/w were evaluated using 3T3 L1 preadipocyte cells. Effect of ASE, LSE and its mixture on intracellular reactive oxygen species (ROS) production were determined by 2', 7'dichlorfluorescein diacetate (DCF DA) staining technique in 3T3-L1 adipocytes. The ability of the herbal extracts and their combination to scavenge super oxide radicals and to inhibit alpha-glucosidase enzyme (a carbohydrate metabolising enzyme) were measured using in vitro methods. RESULTS: The total phenols and tannins were expressed as microgram (microg) of gallic acid equivalents/mg of extract (GAE/mg), flavonoids as microg of quercetin equivalents/mg of extract (QE/mg). LSE had significant higher total phenol (300.11 +/- 1.99), flavonoid (53.12 +/- 0.48) and tannin content (118.90 +/- 0.15) compared to ASE which possessed total phenol (159.93 +/- 0.87); flavonoid (9.37 +/- 0.73) and tannin content (80.5 +/- 0.19). The IC50 value, the concentration of the extracts that cause 50% inhibition or cell death was measured as an index of cytotoxicity. The IC50 value was found to be in the following decreasing order: 1:2 mixture (98 microg/ml) > ASE (323.6 microg/ml) > 1:1 mixture (428.1 microg/ml) > LSE (2154 microg/ml). The 1:1 mixture was comparatively less cytotoxic under the tested concentration range (1 x 10(0) pg - 1 x 10(8) pg) than 1:2 combinations. The results observed with lactate dehydrogenase (LDH) release were similar to that of cell viability assay. The 1:1 mixture (DIA-2 hereafter) was considered for further investigations. DIA-2 inhibited the ROS levels, which is evidenced by the decreased DCF fluorescence. DIA-2 could also efficiently scavenge the super oxide radical generated from PMS/NADH-NBT system showing an IC50 value 69.99 microg/ml, the IC50 value of ASE (157.7 microg/ml), LSE (20.43 microg/ml), and ascorbic acid (49.64 microg/ml) used as positive control. The results of in vitro a-glucosidase inhibitory assay showed highest IC50 value with LSE (0.3 microg/ml) and DIA-2 (0.7 microg/ml) than ASE (136.3 microg/ml) and positive control miglitol (651.8 microg/ml). CONCLUSIONS: DIA-2 exerts synergistic effect in scavenging the ROS and inhibiting the enzyme alpha-glucosidase in vitro compared to its individual extracts. The possible synergistic therapeutic effects may be due the presence of the antioxidant rich flavonoids, phenols and tannins present in LSE and ASE.

Total oligomeric flavonoids of Cyperus rotundus ameliorates neurological deficits, excitotoxicity and behavioral alterations induced by cerebral ischemic-reperfusion injury in rats.

Interactions between neurons and astrocytes play a critical role in the central nervous system homeostasis. Cyperus rotundus (family: Cyperaceae), a traditional Indian medicinal herb, used as nervine tonic and nootropic in the Ayurvedic system of medicine. The present study was undertaken to investigate the neuroprotective effect of total oligomeric flavonoids (TOFs), prepared from C. rotundus, in rat model of cerebral ischemia and reperfusion. Male Sprague Dawley rats (290-340g) were subjected to middle cerebral artery occlusion (MCAO) for 2h and reperfusion for 70h. Experimental animals were divided into four groups: Group I - sham operated (n=7); Group II - vehicle treated ischemic-reperfusion (IR) (n=9), and Group III and IV - TOFs treated (100 and 200mg/kg body weight, p.o., respectively; n=7 in each group). Vehicle or TOFs were pretreated for four days before the induction of ischemia and continued for next three days after the ischemia i.e. treatment was scheduled totally for a period of 7 days. MCAO surgery was performed on day 4, 1h after TOFs administration. Neuroprotective effect of TOFs was substantiated in terms of neurological deficits, excitotoxicity (glutamate, glutamine synthetase and Na(+)K(+)ATPase levels), oxidative stress (malondialdehyde, super oxide dismutase, and glutathione) and neurobehavioral functions in the experimental animals. TOFs decreased glutamate, glutamine synthetase (GS) and increased Na(+)K(+)ATPase activity in a dose dependent manner when compared to the IR rats. Treatment with TOFs significantly reduced the neurological deficits and reversed the anxiogenic behavior in rats. Further, it also significantly decreased MDA and increased superoxide dismutase (SOD) and glutathione content in brains of experimental rats. Histopathological examination using cresyl violet staining revealed the attenuation of neuronal loss by TOFs in stroke rats. The present study demonstrates the unswerving involvement of TOFs on ischemia-reperfusion triggered biochemical alterations in MCAO/R rats. Hence, TOFs might be an attractive candidate for further studies in the development of new drugs for cerebral stroke treatment.

Topical dosage form of valdecoxib: preparation and pharmacological evaluation.

Valdecoxib, a selective COX-2 inhibitor, produces serious side effects when given orally. This has led to its withdrawal. Topical application of valdecoxib was formulated and evaluated for its efficacy and safety. Standard procedures were followed and male Wistar albino rats were used to test the anti-inflammatory effect and effect in hyperalgesic conditions. Ointments, creams, and gels containing valdecoxib 1% (m/m) were prepared. These were tested for physical appearance, pH, spreadability, drug content uniformity, in vitro diffusion. Gel prepared using Carbopol 940 (F-X) was selected after the analysis of the results. Formulation F-X was evaluated for acute skin irritancy, anti-inflammatory effect, optimum effective concentration of valdecoxib, effect on hyperalgesia, inhibition of the granulation tissue formation and anti-arthritic effect. Determination of valdecoxib in test animals plasma and determining the blood clotting time and bleeding time were conducted to study the safety of topical valdecoxib. Valdecoxib gel containing 1% (m/m) of the drug was significantly (p < 0.05) more effective in inhibiting hyperalgesia associated with inflammation, compared to placebo gel, but exhibited significantly (p < 0.05) lower suppression of inflammation than commercial rofecoxib gel. Concentration of valdecoxib used in the preparation minimizes the risk of systemic effects, as shown by the analysis of rat plasma for the presence of valdecoxib; hence, this may be the alternative to oral preparations. The bleeding and clotting time showed no significant difference before and after application of F-X.