Hypoglycemic and Antihyperglycemic Effect ofSemecarpus anacardiumLinn in Normal and Alloxan-Induced Diabetic Rats

In vitro acaricidal properties of Semecarpus anacardium fruit and Datura stramonium leaf extracts against acaricide susceptible (IVRI-I line) and resistant (IVRI-V line) Rhipicephalus (Boophilus) microplus

In an attempt to identify plants having anti-tick properties, the 95% ethanolic and 50% hydro-ethanolic extracts of the fruits of Semecarpus anacardium and leaves of Datura stramonium were evaluated against reference tick lines of Rhipicephalus (Boophilus) microplus. The 95% ethanolic extracts of S. anacardium and D. stramonium caused 50% and 20% mortality, respectively, within 72 h of treatment by adult immersion test. The LC90 value of the ethanolic fruit extract of S. anacardium was determined as 13.5% (CI 12.05-15.12). The extract was also found efficacious (73.3%±3.3%) against the multi-acaricide-resistant IVRI-V line of R.(B.) microplus. The S. anacardium extract significantly affected the reproductive physiology of treated ticks by inhibiting the oviposition and was found safe. The HPTLC fingerprinting profile revealed the presence of pyrocatechol as a marker compound. The acaricidal property of S. anacardium against chemical acaricide-resistant R. (B.) microplus was discussed.

Antidiabetic and antioxidant activities of ethanolic extract of Semecarpus anacardium (Linn.) bark

BACKGROUND

Diabetes mellitus is a global health problem and constantly increasing day by day. The number of diabetic people in world is expected to rise to 366 million in 2030. The available drugs for diabetes, insulin or oral hypoglycemic agents have one or more side effects and search for new antidiabetic drugs with minimal or no side effects from medicinal plants is a challenging for us. The present study was undertaken to investigate the antidiabetic and antioxidant activity of Semecarpus anacardium (Linn.) (abbreviated as SF).

METHODS

The antidiabetic activity was determined by using alloxan-induced diabetic rats. After 15 days of treatment, serum biochemical parameters such as TC, TG, LDL, HDL, SGOT and SGPT were estimated. The survival rate, body weight, organ weight, liver glycogen and blood parameters (RBC and Hb) were also measured. The antioxidant activity was measured by DPPH free radical scavenging assay. Phytochemical screening, total phenolic and total flavonoid content were determined by using standard methods.

RESULTS

The results showed that the survival rate was 100% in rats of Group SA 400. The effect of extract on blood glucose level in Groups SA 100, SA 200 and SA 400 were dose-dependent throughout the treatment period. No significant changes in organ weight to body weight ratio were observed, liver weights significantly improved in Groups SA 200 and SA 400. The bark extract exhibited significant (p < 0.05) anti-diabetic activity with lowering TC, TG, LDL level dose-dependently and protected liver which may be partially explained by attenuation of SGOT and SGPT levels and increases liver glycogen. The percentage of Hb and RBC counts were negatively correlated with the doses of extracts. In DPPH scavenging assay, IC50 values of SA extract and ascorbic acid were found 72.24 μg/ml and 17.81 μg/ml, respectively. Phytochemical screening showed the presence of steroids, triterpenoids, flavonoids, glycosides, saponins, and tannins that were contribute to biological activity.

CONCLUSIONS

These results indicated that stem barks of S. anacardium possess strong anti-diabetic and antioxidant potentials and support traditional medicinal use for the treatment of diabetes mellitus and good source for natural antioxidants.

Catechol alkenyls from Semecarpus anacardium: acetylcholinesterase inhibition and binding mode predictions

ETHNOPHARMACOLOGICAL RELEVANCE

The fruits of Semecarpus anacardium L. f. (Anacardiaceae) are used in Ayurvedic medicine and also in Iranian Traditional Medicine for various indications, among those for retarding and treatment of dementia.

AIM OF THE STUDY

The severity of Alzheimer's disease obviously correlates with a cholinergic deficit. In a screening for acetylcholinesterase (AChE) inhibitory activity, an extract from the fruit resin of Semecarpus anacardium was among the most active ones. Thus, the aim of this study was to isolate the active compounds and to investigate them in detail. Their binding mode to the active site of AChE was investigated by in silico docking experiments.

MATERIALS AND METHODS

From a dichloromethane extract in an activity-guided fractionation the active compounds were isolated under use of different chromatographic techniques. Their structures were unambiguously identified by one and two-dimensional (1)H and (13)C NMR spectroscopy and mass spectrometry and their cholinesterase inhibitory activities were determined by a microplate assay. In order to compare the 3D active sites of AChE from Torpedo californica (TcAChE) and from Electrophorus electricus (EeAChE), three files from the Protein Data Bank (PDB) were used and for docking experiments, GOLD 3.1 software was employed. The concentrations of active compounds in the extract and the fruits were determined by HPLC analysis.

RESULTS

The active compounds were determined as 1',2'-dihydroxy-3'-pentadec-8-enylbenzene (A) and 1',2'-dihydroxy-3'-pentadeca-8,11-dienylbenzene (B). Their IC(50) values in an in vitro assay on AChE inhibition were determined as 12 and 34 μg/mL, respectively, while they were not active in the inhibition of butyrylcholinesterase (BChE). In silico docking experiments showed a similar bioactivity for compounds A and B. The concentration of compounds A and B in the fruits was 1.85% and 1.88%, respectively.

CONCLUSION

In the search for the active principle of the fruit resin of Semecarpus anacardium, compounds A and B were identified as two selective inhibitors for AChE versus BChE.

Modulation of oxidative/nitrosative stress and mitochondrial protective effect of Semecarpus anacardium in diabetic rats

OBJECTIVES

Oxidative and nitrosative stress play an important role in the complications of diabetes mellitus. Free radicals are produced when there is an electron leak in the mito-chondria and a change in the mitochondrial membrane potential. The present study was undertaken to investigate the role of Semecarpus anacardium in protecting the mito-chondria by modulating the production of reactive oxygen species and reactive nitrogen species in diabetic rats.

METHODS

Diabetes was induced using streptozotocin at a dose of 50 mg/kg body weight and, starting 3 days after the induction, Semecarpus anacardium nut milk extract was administered for 21 days. The same duration of study was used for control, diabetes-induced and drug control groups, together with a group treated with metformin. After the experimental period, the animals were sacrificed and the levels of superoxide, hydrogen peroxide, nitrate and nitrite were estimated. Changes in mitochondrial membrane potential, intracellular reactive oxygen species and intracellular calcium were also determined. Confocal laser microscopic images were taken for mitochondria isolated from the liver and kidneys.

KEY FINDINGS

The results of the study revealed that Semecarpus anacardium was able to decrease the production of reactive oxygen and nitrogen species, and reverse the changes in mitochondrial membrane potential and the influx of calcium into the mitochondria.

CONCLUSIONS

The mitochondrial protective effect may be mediated by scavenging of free radicals and complexing of metal ions by virtue of the antioxidative effect of Semecarpus anacardium.

Antidiabetic properties of aqueous barks extract of Parinari excelsa in alloxan-induced diabetic rats

The aqueous extract of the Parinari excelsa barks at doses of 100 and 300 mg/kg/day for 7 days has a significant antihyperglycemic effect on alloxan-induced diabetic rats. At the same dose the acute oral administration of aqueous extract of the P. excelsa barks (100 and 300 mg/kg) induced a significant decrease of blood glucose on glucose-loaded normoglycaemic rats. Our results seem to confirm the rational bases for its use in traditional medicine.