Appetite Suppressing Activity of Rumex Usambarensis Leaf and Stem Aqueous Extract in Wistar Albino Female Rats: an in vivo Experimental Study

Abstract

Background

The burden of obesity and overweight associated morbidity and mortality is increasing in epidemic proportions worldwide. Suppression of appetite is one of the mechanisms that has been shown to reduce weight. Most of the drugs on the market currently for appetite suppression are not readily available or affordable in resource-limited settings. Additionally, previous studies have shown that most of these drugs are associated with significant adverse effects, which demonstrates a need for alternative or complementary options of drugs for appetite suppression. In Uganda, herdsmen commonly chew the raw stems and leaves of Rumex usambarensis, a wild shrub, and this is believed to reduce hunger. This study aimed at determining the effect of Rumex usambarensis aqueous extract on food intake as a measure of appetite in Wistar albino rats.

Methods

This study was carried out in two phases: the fattening phase and the treatment phase. Female albino Wistar rats were fed a high-fat diet for 49 days. The fattened animals were then randomly separated into 4 groups, which received 1 mL of distilled water (negative control), 500 mg/kg body weight of aqueous extract of Rumex usambarensis, 1000 mg/kg body weight of the extract and 20 mg/kg body weight topiramate (positive control), respectively. Food intake was measured every day, and weights were taken every two days for every group.

Results

Rumex usambarensis extract significantly reduced body weight of fattened rats compared to the control group at both doses: for the 500mg/kg dose (Mean difference, MD = 17.2, p < 0.001) and for 1000mg/kg dose (MD = 25.9, p < 0.001). Additionally, both doses of the aqueous extract showed a significant reduction in food intake: for the 500mg/kg dose (MD = 16.1, p < 0.001) and for the 1000mg/kg dose (MD = 37.3, p < 0.001). There was a strong correlation between food intake and weight for both doses for the 500mg/kg dose (r = 0.744, p = 0.009), and the strongest association observed with 1000mg/kg dose (r = 0.906, p < 0.001).

Conclusion

The aqueous extract of the leaves and stems of Rumex usambarensis has appetite suppressing and weight reduction effects in fattened female Wistar albino rats and could be an efficacious alternative medicine for management of overweight, obesity and other related disorders.

Keywords:

• Rumex usambarensis
• appetite
• weight
• obesity
• dammer

Abbreviations

ANOVA, Analysis of variance; MD, Mean difference; MUST, Mbarara University of Science and Technology; NIH, National Institute of Health; S.E, Standard Error; SPSS, Statistical Package for the Social Sciences.

Data Sharing Statement

The datasets used and analyzed during this study are available from the author upon request.

Macy staff and our parents for all the guidance and support during this study.

Ethical Approval and Animal Care

The research proposal was approved by the MUST Department of Pharmacy Research Committee and the Research and Ethics Committee of Mbarara University of Science and Technology. All animals were humanely treated as per the National Institute of Health (NIH) guidelines for the care and use of laboratory animals.⁴⁷ This included acquiring, caring for, using and disposing of animals in compliance with current state and local laws and regulations and with professional standards. Reasonable efforts were made to ensure their comfort, health, and humane treatment and minimize pain. Proper animal handling techniques were followed regarding feeding, housing, and general handling throughout the study period.

Consent for Publication

All the authors agreed to the submission of this manuscript for publication.

Acknowledgments

We wish to acknowledge all the staff of the Mbarara University of Science and Technology (MUST) pharmaceutical analysis laboratory and the MUST animal research laboratory where this study was conducted, and the MUST Department of Pharmacy staff and our parents for all the guidance and support during this study.

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; have 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 report no conflicts of interest in this work.

Additional information

Funding

This study did not receive any external funding.