ABSTRACT
Anaemia constitutes a serious health problem in many developing countries due to the prevalence of malaria, sickle cell disorder, malnutrition, and other chronic diseases. A growing number of research submit that dietary polyphenols play a critical role in the management of anaemia. This study was aimed at evaluating the anti-anaemic potentials of methanol extract of Solenostemon monostichous (SM) and chloroform-ethanol (50:50) extract of Abelmoschus esculentus (AE) leaves in phenylhydrazine-induced anaemia and low protein diet-induced anaemia in Wistar rats. Evaluation of the proximate content, vitamins, amino acids, and mineral elements contents; phytochemical constituents, and antioxidant status of both plants’ extracts were determined using established protocols. Anti-anaemic effects of the extracts in Wistar albino rats were assessed using two models, phenylhydrazine and low protein diet to induce anaemia. The most active extracts were thereafter fractionated with solvents of different polarities, and the fractions were subjected to GC-MS analysis. Proximate analysis of the extracts showed that they contain ample amounts of carbohydrates, moisture, and proteins and moderate levels of crude ash, fibre, and fat content. Minerals, vitamins, and amino acids analyses of the extracts reveal that they are rich sources of these compounds. Qualitative phytochemical screening of the extracts indicated the presence of some important phytochemicals. Quantitatively, both extracts showed non-significant (p > 0.05) changes in total phenol content and ability to inhibit lipid peroxidation. Total tannin and flavonoid contents were significantly (p < 0.05) high for both extracts. S. monostachyus had better DPPH radical scavenging ability than the A. esculentus counterpart. Acute toxicity study revealed that both extracts were non-toxic with their LD50 values greater than 5000mg/kg. The phenylhydrazine (PHZ) study revealed that treatment of the PHZadministered rats with either S. monostachyus or A. esculentus extracts resulted in remarkable improvements in some biochemical parameters including hematological indices, erythropoietin level, antioxidant status, liver function, kidney function, electrolytes as against the PHZ-administered rats. Results from the PEM study showed that the low protein (2%) diet-fed rats (negative control) showed severe physical evidence of marasmic-kwashiorkor as against the extracts-treated or Fesolate® tablet (reference haematinic drug; negative control) supplemented groups which showed moderate to mild forms of these symptoms. Hematological indices were significantly (p < 0.05) higher in the extracts treated groups when compared with the low protein diet-fed rats (negative control). The changes noticed in some oxidative stress indices (GPx, MDA, GSH, SOD, CAT) in the liver, kidney, and spleen tissues; liver function (ALT, AST, total protein, albumin, bilirubin, total cholesterol, LDL cholesterol, HDL cholesterol, VLDL cholesterol, and triacylglycerol), electrolytes (Na, K, Cl, and bicarbonate ions) and erythropoietin levels in the serum of the negative control were abated by the administration of the extracts (250 and 500 mg/kg body weight) or haematinic drug to near-normal or normal levels. GC-MS analysis of the most active fractions (hexane and dichloromethane fractions) from both plants revealed the presence of non-polar hydrocarbons, mainly fatty acids, notably oleic acid and neophytadiene. The overall findings support local claims on the anti-anaemic potential of S. monostachyus and A. esculentus leaves in folklore medicine which may be exploited as supplements in the management of anaemia.
