Hibiscus ameliorates salt-induced carotid intima-media thickness in albino rats

Objectives: The carotid intima-media thickness (CIMT) is a known biomarker of clinical and subclinical cardiovascular events and evaluation of therapeutic action. Excessive salt directly causes changes in the common carotid intima and media layers and has been linked to hypertensive disease resulting to changes on vascular structure. Hibiscus sabdariffa is a traditional herbal drink with antihypertensive effects. The anatomical aspects of its effects however, are largely unknown. This study therefore, investigated the effects of hibiscus extract on CIMT in rats fed with a high-salt diet. Methods: Young albino rats (Rattus norvegicus) were divided into three groups: (A) high-salt diet alone, (B) high-salt diet and Hibiscus sabdariffa extract and (C) control group fed a normal diet for 8 weeks. Specimens from carotid arteries of rats were fixated and processed for paraffin embedding. Seven-micrometer thick sections were stained with Hematoxylin and Eosin stain and examined under light microscopy. Morphometric measurements were taken to determine the CIMT. Results: High-salt diet increased CIMT from 497.86 µm to 697.85 µm in 8 weeks. In Hibiscus sabdariffa extract fed rats, the CIMT decreased to 542.85 µm (p<0.05) by week 8. Conclusion: Hibiscus sabdariffa extract ameliorates salt-induced increase in CIMT in rats in a time-dependent manner. This implies that Hibiscus sabdariffa products may have therapeutic value in salt-induced vascular morbidity.