Histopathologic studies of aqueous extracts of five selected local edible vegetables in isoproterenol-induced myocardial infarction in male Wistar albino rats

A healthy diet plays a vital role in the overall wellbeing of humans. Vegetables constitute a substantial portion of most daily diet and are a part of an overall healthy diet in many developing countries [1 – 2]. This study investigated the cardioprotective effects of aqueous extracts of five leaf vegetables: L. taraxacifolia (Wild lettuce), C. crepidioides (Fireweed), S. nigrum (Black nightshade), B. alba (Indian spinach) and S. biafrae (English spinach) extracts were obtained using maceration techniques. Cardioprotective effects were evaluated in male Wistar rats using the isoproterenol-induced myocardial infarction (ISO) model. Rats weighing between 150 – 200 g were randomized into eight groups of five rats each. Groups A and B served as normal and ISO controls and were fed with rat's pellet and water ad libitium [3]. Groups C, D, E, F, G and H were the experimental groups orally administered 200 mg kg-1bw-1 of each extract respectively. Group H however, received a combination of all the extracts in ratio 1:1:1:1:1. On day 29 and 30, the various groups (Group C to H) including ISO control (Group B) were subcutaneously administered ISO at a dose of 20 mg kg-1 bw-1 to induce myocardial infarction after pre-treatment with the extracts for 28 days. The heart was processed as described by [4]. Histopathologic examination [A-H] revealed normal cytoarchitecture in Group A animals (normal control) (Figure 1). The ISO control group showed degeneration of myocytes with slendering of fibre, loss of nuclei, loss of cross striation of the cardiac muscles and an increase in interfibre space (Oedema). These conditions were significantly reduced in the treated groups that received the extracts except in group C that received L. taraxacifolia extract. It was observed that group H showed normal myocardial fibers as compared to the ISO group.

Fig. 1: The hispathologic result showing different architecture of myocardial fibres in untreated (Group A & B) and pretreated (Group C – H) group of rats.

We therefore, suggest that the vegetable extracts may be effective and safe in proper management and prevention of myocardial infarction.

Keywords: myocardial infarction, isoproterenol, histopathologic examination, vegetables, Launaea taraxacifolia, Crassocephalum crepidioides, Basella alba, Senecio biafrae

References:

[1] Anandarajagopal, K., Sudhahar, D. et al., 2011. Evaluation of CNS Depressant Activity of Aerial Parts of Basella alba Linn. IJPI'S JPT 1(5): 1 – 6.

[2] Mahendra, A. G. et al., 2010. Evaluation of CNS Depressant Activity of Aerial Parts of Basella alba Linn. IJNPR 1(4):485 – 492.

[3] Asuquo, O. R., Igiri, A. O. et al., 2010. Cardioprotective Potential Of Vernonia Amygdalina And Ocimum Gratissimum Against Streptozotocin (Stz) – Induced Diabetes In Wistar Rats. IJTM 7(1): DOI: 10.5580/90

[4] Dury, R. and Wallington, E. Carlton's Histological Techniques, 6th edition. London: Oxford University Press; 1983. pp. 303 – 306.