Antioxidant-rich Terminalia catappa fruit exerts antihypertensive effect via modulation of angiotensin-1-converting enzyme activity and H₂S/NO/cGMP signalling pathway in Wistar rats

Abstract

Introduction

The present study aimed at investigating the effect of Terminalia catappa fruits on blood pressure, NO/cGMP signalling pathway, angiotensin-1-converting enzyme and arginase activity, and oxidative stress biomarkers in L-NAME-induced hypertensive rats.

Materials and methods

Forty-two Wistar rats were divided into seven groups. Hypertension was induced via oral administration of 40 mg/kg of L-NAME for 21 days. Thereafter, the hypertensive rats were treated with Terminalia catappa fruit-supplemented diet and sildenafil citrate for 21 days. The blood pressure was measured and cardiac homogenate was prepared for biochemical analyses.

Results

The results showed that L-NAME caused a significant (p < 0.05) increase in systolic and diastolic blood pressure, and heart rate as well as ACE, arginase and PDE-5 activity, with a simultaneous decrease in NO and H₂S levels as well as increased oxidative stress biomarkers. However, treatment with Terminalia catappa fruits-supplemented diets and sildenafil citrate lowered blood pressure and modulated ACE, arginase, and PDE-5 activity, improved NO and H₂S levels, as well as antioxidant status.

Conclusion

Findings presented in this study provide useful information on the antihypertensive property of Terminalia catappa fruits, alongside some possible mechanisms. Hence, Terminalia catappa fruits could be considered a dietary regimen and functional food in alleviating hypertension.

Keywords:

• Hypertension
• Terminalia catappa fruits
• NO/cGMP signalling pathway
• sildenafil citrate

Authors’ contribution statement

Adeniyi A. Adebayo: Conceptualisation, Funding acquisition, Experimental, Data analysis, Validation, Writing – Original draft, review and editing. Ayokunle O. Ademosun: Conceptualisation, Supervision, Writing – Original draft, review and editing. Bukola C. Adedayo: Writing – Original draft and editing. Ganiyu Oboh: Conceptualisation, Supervision, Writing – Review.

Disclosure statement

No potential conflict of interest was reported by the authors.

Data availability statement

Data are available on request.

Additional information

Funding

The author(s) reported there is no funding associated with the work featured in this article.