Antidiarrheal Activities of the Methanol Leaf Extracts of Olinia rochetiana (Oliniaceae) Against Castor Oil-Induced Diarrhea in Mice

Abstract

Background

Olinia rochetiana has been used traditionally to cure diarrheal disease. Therefore, this study aimed to investigate the acute toxicity and antidiarrheal effect of O. rochetiana leaf extracts.

Methods

Cold maceration was used to extract plant leaf powder with 80% methanol. The extract’s antidiarrheal action was tested against a castor oil-induced diarrheal model, a charcoal meal test, and enteropooling tests at doses of 100, 200, and 400 mg/kg. Negative controls received the vehicle at 10 mL/kg, while positive controls received loperamide at 3 mg/kg.

Results

From the study, no apparent toxicity was observed when a single dose of 2000 mg/kg was administered. In the castor oil-induced model, the extract delayed the onset of diarrhea, reduced stool frequency, and decreased wet feces weight and number in a dose-dependent manner at 200 mg/kg (p < 0.05) and 400 mg/kg (p < 0.01). The percent reduction in moist feces at 100, 200, and 400 mg/kg was 54.2, 23.97, and 18.26%, respectively, indicating a significant dose-dependent decrease. In a charcoal meal test, the extracts at 200 and 400 mg/kg revealed a peristaltic index of 65 and 46%, respectively, with considerable inhibition of charcoal transport at 23 and 39%. The weight and volume of intestinal contents dropped significantly at a dose of 400 mg/kg (p < 0.01), which is 0.43 mg/kg, in the enteropooling test when compared with the tested dose. The computed in vivo antidiarrheal index revealed diarrheal inhibition values of 46.06 and 71.06% at 200 and 400 mg/kg, respectively.

Conclusion

In the current investigation, O. rochetiana showed significant antidiarrheal activity with no symptoms of toxicity in mice.

Keywords:

• antidiarrheal activity
• castor oil-induced diarrhea
• gastrointestinal transit time
• enteropooling
• Olinia rochetiana

Abbreviations

ADI: Antidiarrheal Index, ANOVA: Analysis of Variance, IRB: Institutional Review Board, MVICC: Mean volume of the intestinal content of control group, MVICT: Mean volume of the intestinal content of test group, OECD: Organization for Economic Co-operation and Development, WHO: World Health Organization.

Data Sharing Statement

The corresponding author will provide all the datasets used and analyzed during the current work upon reasonable request.

Ethical Approval

Ethical clearance and approval were obtained from the institutional review board (IRB) with Ref No: IRB/204/14 from Hawassa University, College of Medicine and Health Sciences.

Acknowledgments

We gratefully acknowledge the Ethiopian Public Health Institute (EPHI) for providing laboratory space, animals, and laboratory sets for this work, as well as Hawassa University’s College of Medicine and Health Science School of Pharmacy for financial support. This manuscript’s full thesis is available on the Hawassa University repository at this link: http://etd.hu.edu.et//handle/123456789/3651.

Author Contributions

All authors made a significant contribution to the work reported, whether that is in the conception, study design, execution, acquisition of data, analysis and interpretation, or in all these areas; took part in drafting, revising or critically reviewing the article; gave final approval of the version to be published; agreed on the journal to which the article has been submitted; and agree to be accountable for all aspects of the work.

Disclosure

The authors declare they have no competing interests in this work.

Additional information

Funding

This study was funded by the School of Pharmacy, College of Medicine and Health Science, Hawassa University.