Many Jatropha species have found applications in folk medicine. This study aimed to evaluate the biological activities of the total alcoholic extracts from the roots and aerial parts of Jatropha pelargoniifolia and Jatropha glauca that belong to Euphorbiaceae family native to Saudi Arabia. In vivo and in vitro studies were carried out to evaluate their possible activities as hepatoprotective, antinociceptive, anti-inflammatory, and antidiabetic/hypoglycemic agents in comparison to standard clinical drugs. Hepatoprotective effect was assessed via changes in serum biochemical parameters, including aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), gamma glutamyl transpeptidase (GGT), and total bilirubin content. Tissue parameters, such as presence of malonaldehyde (MDA), non-protein sulfhydryl groups (NP-SH), and total protein (TP), were also measured. Antinociceptive activity was explored by the hot plate and writhing methods. In addition, the anti-inflammatory effect was evaluated by carrageenan-induced paw edema. Finally, hypoglycemic and antidiabetic activities in alloxan-induced diabetic mice were evaluated for extracts from both the Jatropha plants.
Results: the roots of J. glauca showed higher hepatoprotective activity as well as superior antinociceptive activity (63.85%) in comparison to indomethacin (69.8%). In addition, the root extracts from J. pelargoniifolia exhibited higher anti-inflammatory effect (50.63%) and hypoglycemic activity (37.98%) as compared to phenylbutazone (64.63%) and glibenclamide (51.57%), respectively. Finally, extracts from aerial parts of J. glauca showed significant antidiabetic activity in alloxan-induced diabetes (39.93%) cases as compared to glibenclamide (47.13%). Conclusion: the ethanolic extracts from J. glauca and J. pelargoniifolia (root and aerial parts) induced analgesic and anti-inflammatory effects; these results emphasizes the main purpose of using these plants in folk medicine as analgesic and for the treatment of inflammatory conditions. As well, the selected plants showed significant hepatoprotective and hypoglycemic/antidiabetic activities.