Tumour Suppressive and Organ Protective Effects of Aqueous Andrographis paniculata Leaves Extract on Benzene Induced Leukaemia Bearing Rats

Abstract

Aims: To investigate and compare the protective and ameliorative role of aqueous leaf extract of Andrographis paniculata and standard drug 5-Fluorouracil on select organs of male Wistar rats exposed to benzene carcinogen. Study Design: Histological assessment of protective and ameliorative activity of the aqueous leaf extract of Andrographis paniculata and standard drug 5-Fluorouracil in some organs of experimental animals exposed to benzene carcinogen. Place and Duration of Study: Department of Biomedical Sciences Ladoke Akintola University of Technology, College of Health Sciences, Osogbo. Nigeria between May and August 2012. Methodology: 72 adult male Wistar rats weighing 150-180 g were grouped into six (A-E), each group comprised of 6 rats in replicate of two (n=12). Group A (control) received distilled water and normal saline (0.5 ml/kg each), group B received benzene chromasolv (0.2 ml at 1:10 dilution (water/2-propanol), group C received aqueous Andrographis paniculata (10 mg/kg bodyweight), group D was administered 5 -fluorouracil only (5 mg/kg body weight) for four weeks, group E was pretreated with Andrographis paniculata for 4 weeks prior to the administration of benzene chromasolv and group F was post treated with Andrographis paniculata for 4 weeks after pre-exposure to benzene chromasolv for 4 weeks. Leukaemia burden was assessed using haematological parameters such as Packed cell volume, Haemoglobin concentration, Red blood cells count and Total leukocyte count in the control and treatment groups. Results: Results showed that leukemia was induced within 4 weeks as a significantly elevated WBC (leukocyte) counts and anaemia over the group not exposed to benzene which served as baseline were noted (p< 0.05).Organ histology showed varying lesions of the heart (mild to marked) coronary congestion, severe vacuolar degeneration and necrosis of the hepatocytes with cellular infiltration by mononuclear cells, diffuse tubular degeneration and necrosis with renal interstitial hemorrhage observed in the groups exposed to benzene carcinogen, 5-Fluorouracil and co-treatments of these two agents. However, hepato-renal and heart histio-architectures were intact in the extract pre-treatment and post-treatment groups. Conclusion: These results suggest that Andrographis paniculata might be more effective than some other drugs currently in use as cancer suppressive chemotherapeutic agents and also may be a novel bioagent for the treatment of acute or chronic injuries induced on the liver, kidneys and heart by toxicants and carcinogens.