Effect of the leaves aqueous extract of Jodina rhombifolia (Hook. & Arn.) Reissek (Santalaceae) on intestinal function and its acute toxicity.

ETHNOPHARMACOLOGICAL RELEVANCE: In Argentine traditional medicine it is recorded the use of Jodina rhombifolia (Hook. & Arn.) Reissek (Santalaceae) leaves for treating various affections that compromise the intestinal normal functioning. AIM OF THE STUDY: The aim of this study was to assess the effect of J. rhombifolia leaves lyophilized aqueous extract on the intestinal function by means of in vivo and ex vivo experimental assays for determinate the antidiarrheal and antispasmodic capacity. Furthermore, was to evaluate its acute toxicity potential by oral and intraperitoneal administration of extract. MATERIALS AND METHODS: The in vivo assays were conducted by the experimental techniques of intestinal transit in mice, intestinal fluid accumulation in rats and Castor oil-induced diarrhea in mice. In the ex vivo assays, isolated rat duodenum and ileum segments were used for to evaluate the antispasmodic activity through contractile concentration-response curves induced by Carbachol and CaCl2. The acute toxicity of the extract was also investigated by oral and intraperitoneal administration. RESULTS: The extract intraperitoneal administration at the doses 125, 250 and 500 mg/kg, caused a marked reduction in the normal intestinal transit and in the number of diarrheal episodes in a dose-dependent manner. However, the extract did not produce significant changes in the intestinal fluid accumulation with any of the tested dose. The extract demonstrated a non-competitive inhibitory effect on the contractions of intestinal smooth muscle experimentally provoked by the spasmogenic agents Carbachol and CaCl2 in a dose-dependent manner (IC50 = 10.57 ± 1.38 and 6.29 ± 1.54 mg extract/ml Tyrode solution in the isolated organ bath, respectively). ANOVA indicated a significative effect of treatment (p < 0.001). CONCLUSIONS: The scientific evidence achieved based in the used experimental models allows us to indicate that J. rhombifolia leaves lyophilized aqueous extract manifest an antispasmodic activity on intestinal smooth muscle without observation of apparent toxicity symptoms.

Jodina rhombifolia leaves lyophilized aqueous extract decreases ethanol intake and preference in adolescent male Wistar rats.

The leaves of Jodina rhombifolia (Hook. & Arn.) Reissek (Santalaceae) are utilized as anti-alcoholic in Argentine folk medicine. This study was designed to investigate the anti-alcohol properties in adolescent male Wistar rats (postnatal day 29; 83-105 g of weight). We utilized the "self-administration model", which ethanol was offered in the standard home-cage through two-bottle free-choice regimen between an ethanolic solution (20% in tap water, v/v) and tap water with unlimited access for 24h per day for 10 consecutive days. The results obtained show that repeated administration of J. rhombifolia lyophilized extract, markedly reduced ethanol voluntary intake on dose dependent bases. The magnitude in reduction of daily ethanol intake was approximately 29%, 44% and 68%, for the rat groups treated with 62.5, 125 and 250 mg/kg of extract, respectively. Ethanol preference (proportion of ethanol intake versus total fluid intake) was significantly reduced: 21.37% ± 0.79 (0 mg/kg); 15.83% ± 0.93 (62.5 mg/kg); 15.22% ± 1.30 (125 mg/kg) and 9.38% ± 0.57 (250 mg/kg). Daily food intake was significantly higher (p<0.05) in the group treated with 250 mg/kg of JRLE in comparison with vehicle-dose group; the reduction in ethanol intake was associated with a compensatory increase in food intake, probably because in the control group animals a part of the total caloric intake was supplied by ethanol. Treatment was very well tolerated by all animals and without apparent side-effects. These results contribute to the scientific validation of the antialcoholic indication of this botanic species in Argentine folk medicine.

Reduction in voluntary ethanol intake following repeated oral administration of Jodina rhombifolia lyophilized aqueous extract in male Wistar rats.

ETHNOPHARMACOLOGICAL RELEVANCE: The leaves of Jodina rhombifolia (Hook. & Arn.) Reissek (SANTALACEAE) is utilized in Argentine folk medicine for the treatment of alcoholism. AIM OF THE STUDY: To evaluate the antialcoholic activity of Jodina rhombifolia lyophilized aqueous extract (JRLE) in male Wistar rats. MATERIALS AND METHODS: Rats were housed individually in standard plastic cages with wood chip bedding. Throughout the duration of experiment, ethanol was offered in the standard home-cage; two-bottle free-choice regimen between an ethanolic solution (20% in tap water, v/v) and tap water with unlimited access for 24h per day for 10 consecutive days. Rats were administrated intragastrically twice daily (1 ml/200 g) for 10 consecutive days, with the control vehicle (distilled water) or one of the doses of JRLE (125, 250 and 500 mg/Kg weight). Body weight, ethanol, water and food intake were measured every day at the same hour during the 10 days of experimentation. RESULTS: The reducing effect of JRLE on daily ethanol intake was evidenced from the first day of treatment and persisted throughout the entire treatment period. The treatment did not significantly affect daily water intake neither the body weight gain. Daily food intake was higher in rat groups treated with JRLE. CONCLUSION: The results obtained in the present preliminary study show that repeated administration of JRLE, markedly reduces ethanol voluntary intake in male Wistar rats. The reduction of consumption was of remarkable magnitude and stable during the treatment 10-days.

Effect of dehydroleucodine on intestinal transit: structural basis of the interaction with the α(2)-adrenergic receptor.

The activity of dehydroleucodine, a sesquiterpene lactone obtained from Artemisia douglasiana, was studied in mice small intestinal transit. Its mechanism was evaluated in the presence of several adrenergic and cholinergic antagonist drugs and one opioid antagonist. Docking of dehydroleucodine into the homology model of the α2-adrenergic receptor allowed us to analyze the structural basis of their interactions. The experiments showed that dehydroleucodine delayed intestinal transit. The docking of dehydroleucodine showed a unique binding site, equivalent to the binding site of carozolol in the ß-adrenergic receptor. The results suggested that dehydroleucodine produced an inhibitory effect on intestinal transit. Its action could be mediated, at least in part, through the α2-adrenergic receptor.