Abnormalities in carbohydrate and lipid metabolisms in high-fructose dietfed insulin-resistant rats: amelioration by Catharanthus roseus treatments

Medicinal plants utilized in Thai Traditional Medicine for diabetes treatment: Ethnobotanical surveys, scientific evidence and phytochemicals

ETHNOPHARMACOLOGICAL RELEVANCE

Diabetes mellitus remains the most lethal metabolic disease of contemporaneous times and despite the therapeutic arsenal currently available, research on new antidiabetic agents remains a priority. In recent years, the revitalization of Thai Traditional Medicine (TTM) became a clear priority for the Thai government, and many efforts have been undertaken to accelerate research on herbal medicines and their use in medical services in various hospitals. Additionally, and particularly in rural areas, treatment of diabetes and associated symptomatology frequently relies on herbal preparations recommended by practitioners of TTM. In the current work, medicinal plants used in Thailand for treating diabetes, as well as their hypoglycaemic pharmacological evidences and potential therapeutic use for diabetes-related complications were reviewed.

MATERIALS AND METHODS

Ethnopharmacological information on the plant materials used in TTM for diabetes treatment was collected through literature search in a range of scientific databases using the search terms: diabetes, folk medicine, Thailand medicinal plants, traditional medicine. Information regarding scientific evidence on the antidiabetic effects of surveyed species was obtained considering not only the most common taxonomic designation, but also taxonomic synonyms, and including the keywords 'diabetes' and 'hypoglycaemic effect'.

RESULTS

A total of 183 species known to be used for diabetes management in TTM were reviewed, with 30% of them still lacking experimental evidences to support claims regarding the mechanisms and phytochemicals underlying their antidiabetic properties. Moreover, a total of 46 bioactives displaying effective antidiabetic effects have been isolated from 24 species, their underlying mechanism(s) of action being fully or partially disclosed.

CONCLUSIONS

We deliver the most extensive survey dealing with the ethnomedicinal knowledge of Thai medicinal plants utilized on diabetes management. We are certain that the current review will spark further research on Thai plants for the development of new standardized phytomedicines through drug discovery programmes.

Vindoline effectively ameliorated diabetes-induced hepatotoxicity by docking oxidative stress, inflammation and hypertriglyceridemia in type 2 diabetes-induced male Wistar rats

Vindoline, an indole alkaloid present in the leaves of Catharanthus roseus plant, has been recently reported to have insulotropic effects. This present study evaluated the possible hepatoprotective effects of vindoline in a type 2 diabetes mellitus rat model. Diabetes mellitus was induced by exposing rats to 10% fructose water for two weeks followed by a single intraperitoneal injection of 40 mg/kg body weight of streptozotocin (STZ). Rats were randomly divided into six groups (n = 8) and treated daily for 6 weeks with the vehicle via oral gavage, vindoline (20 mg/kg) or glibenclamide (5 mg/kg). Weekly fasting blood glucose (FBG) levels and body weight were measured and recorded. Administration of vindoline significantly (p < 0.05) reduced FBG by 15% when compared to the diabetic controls. Vindoline significantly (p < 0.05) decreased diabetes-induced hepatic injury shown by decreased levels of serum alanine transferase (ALT) (-42%), aspartate aminotransferase (AST) (-42%) and alkaline phosphatase (-62%) compared to the diabetic controls. The oxygen radical absorbance capacity and the activities of superoxide dismutase (SOD) and catalase (CAT) were also improved following treatment with vindoline. The results also showed decreased levels of pro-inflammatory cytokines such as TNF-ɑ by (-41%) and IL-6 (-28%) which may have also contributed to the reduction of serum triglycerides (-65%) in the diabetic group treated with vindoline. Histopathological findings showed improvement of both the hepatic and pancreatic tissues following vindoline treatment. Overall, these findings suggest that vindoline may protect the diabetic hepatic tissue from injury via antioxidant, anti-inflammatory and anti-hypertriglyceredemia mechanisms thereby retarding the development of diabetic complications.

S, Sankar P, Bobby Z. Study the effect of s-methyl L-cysteine on lipid metabolism in an experimental model of diet induced obesity

BACKGROUND

S-methyl L-cysteine (SMC) is a hydrophilic cysteine-containing compound naturally found in Alium plants such as, garlic and onion.

OBJECTIVES

The present study was aimed to evaluate the hypoglycemic and antihyperlipidemic properties of SMC in high fructose induced diabetic rats.

MATERIAL AND METHODS

The present study was designed to evaluate the hypoglycemic and antihyperlipidemic properties of SMC in high fructose induced diabetic rats. Blood samples were collected and the fasting plasma glucose, lipid profile, total antioxidant status (TAS) aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were estimated using standard procedures. Differences between the groups were assessed by using One way Analysis of Variance with (ANOVA) Tukey post hoc test.

RESULTS

Oral administration of SMC at a dose of 100 mg/kg bodyweight/day to HFD-treated rats for a period of 60 days showed significant reduction in the animal weight, fasting plasma glucose, total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), VLDL-C and elevation in the level of high-density lipoprotein cholesterol (HDL-C) and TAS compared with fructose fed group. The effects of SMC was compared with metformin; a well-known antihyperglycemic drug.

CONCLUSION

In conclusion, SMC found to be effective in improving the high fructose induced hyperglycemia and dyslipidemia. It may possibly provide a potential adjuvant for the treatment and management of diabetes.