Antihyperglycemic and Antihyperlipidemic Effects of Lippia citriodora in Rats

Effect of Pelargonium graveolens on Glucose Metabolism in Streptozotocin-Induced Diabetic Rats

AIMS

The study aimed to assess the antihyperglycemic activity of Pelargonium graveolens.

BACKGROUND

Pelargonium graveolens (P. graveolens) (Geraniaceae) is a medicinal plant frequently used in traditional medicine in Morocco and Algeria as remedy against a multitude of illnesses. Interestingly, it is used in the Moroccan pharmacopeia for managing diabetes.

OBJECTIVE

The current study was carried out in order to assess the antihyperglycemic activity of P. graveolens in normal and streptozotocin(STZ)-induced diabetic rats, as well as to evaluate the acute toxicity of the leaves aqueous extract of Pelargonium graveolens (PGLAE).

METHODS

The therapeutic effect of PGLAE at a dose of 40 mg/kg on blood glucose levels was investigated in normal and STZ-induced diabetic rats after a single oral (6h) and a repeated (15 days) oral administration. The acute toxicity of the PGLAE was examined in accordance the OECD test guideline. Post-treatment, body weight, signs of toxicity, and/or mortality were observed for 14 days. Further assays such as the oral glucose tolerance test, histopathological examination and antioxidant activity was also performed according to standard protocols.

RESULTS

Findings exhibited that both single and repeated oral doses of PGLAE (40 mg/kg) produced significant reduction of blood glucose levels in normal and diabetic rats. All treated animals survived and no apparent adverse effects were observed during the duration of the acute toxicity study. Importantly, oral LD50 of PGLAE was greater than 2000 mg/kg BW. Furthermore, a remarkable influence on glucose tolerance was also noticed after PGLAE treatment. Moreover, PGLAE was able to improve histopathological structure of liver and possesses a potential antioxidant effect in vitro.

CONCLUSION

In conclusion, this study reports the antidiabetic effect of PGLAE in rats supporting then its traditional use for the management of diabetes.

In vitro α-glucosidase inhibition by Brazilian medicinal plant extracts characterised by ultra-high performance liquid chromatography coupled to mass spectrometry

Aiming at finding natural sources of antidiabetics agents, 15 extracts from Brazilian medicinal plants of the Atlantic Forest and Amazon region were tested against α-glucosidase enzyme. Plants were selected based on the taxonomic relationships with genera including several species with antidiabetic activity. In this screening, the extracts obtained from the flowers of Hyptis monticola and the leaves of Lantana trifolia and Lippia origanoides resulted endowed with promising anti-α-glucosidase activity. The extracts from H. monticola and from L. origanoides collected in two different areas, were characterised by ultra-high performance liquid chromatography coupled to mass spectrometry. Bioassay-guided fractionation led to the identification of several enzyme inhibiting compounds, among them the mechanism of action of naringenin and pinocembrin was investigated. The two L. origanoides extracts showed differences in bioactivity and in the phytochemical profiles. The fractionation of the extract from H. monticola led to a partial loss of the inhibitory effect.