[01] Usunobun Usunomena, Department of Basic Sciences (Biochemistry Unit), Faculty of Basic and Applied Sciences, Benson Idahosa University, Benin City, Edo State, Nigeria. [02] Okolie P. Ngozi, Department of Biochemistry, Faculty of Life Sciences, University of Benin, Benin City, Nigeria. [03] Eze G. Ikechi, Department of Anatomy, School of Basic Medical Sciences, College of Medicine, University of Benin, Benin City, Nigeria.

This experiment pertains to the protective role of Vernonia amygdalina pre-treatment on some biochemical indices in dimethylnitrosamine (DMN)-induced liver damage in male albino rats. Four (4) groups of six (6) rats each were used for the study. Group 1served as control, group 2 and 3 were pre-treated with 400mg/kg Vernonia amygdalina for one week while group 3 and 4 each received single dose of 20mg/kg DMN (orally) after one week. The rats were sacrificed 48hrs after DMN administration. In rats administered 20mg/kg DMN, liver damage was clearly shown by increased activities of serum hepatic marker enzymes namely aspartate aminotransaminase (AST), alanine aminotransaminase (ALT), alkaline phosphatase (ALP), and gamma glutamyltransferase (GGT), increased lipid profile parameters such as total cholesterol and triglycerides as well as increased level of lipid peroxidation indices, malondialdehyde (MDA) in liver. The toxic effect of DMN was also indicated by significantly decreased levels of antioxidants such as superoxide dismutase (SOD), catalase (CAT) and reduced glutathione (GSH). However, in rats pre-treated with 400mg/kg Vernonia amygdalina and dosed thereafter with DMN, there were significant reversal in the activities of serum hepatic marker enzymes, lipid profiles, lipid peroxidation and significant restoration of antioxidant levels in the liver when compared to DMN-alone treated rats. Histopathological studies in the liver of rats also showed that Vernonia amygdalina pre-treatment markedly reduced the toxicity of DMN and significantly preserved the normal histological architecture of the tissue. The findings of this study suggest that pre-treatment with Vernonia amygdalina leaves has a protective and beneficial effect on liver subjected to DMN-induced oxidative stress, possibly by decreasing lipid peroxidation and enhancing endogenous antioxidant production.

Antioxidant, Dimethylnitrosamine, Necrosis, Oxidative Stress, Vernonia Amygdalina

[01] Farombi, E. O., and Owoeye, O. (2011). Antioxidant and chemopreventive properties of Vernonia amygdalina and Garcinia biflavonoid. International Journal of Environmental Research and Public Health 8: 2533–2555. [02] Igile, G. O., Oleszek, W., Jurzysta, M., Burda, S., Fanfunso, M., and Fasanmade, A. A. (1994). Flavonoids from Vernonia amygdalina and their antioxidant activities.Journal of Agricultural and Food Chemistry 42: 2445–2448. [03] Atangwho, I. J., Ebong, P. E., Eyong, E. U., Williams, I. O., Eteng, M. U., & Egbung, G. E. (2009). Comparative chemical composition of leaves of some antidiabetic medicinal plants: Azadirachta indica, Vernonia amygdalina and Gongronema latifolium. African Journal of Biotechnology, 8(18): 4685–4689. [04] Usunobun U and Okolie N. P (2015). Phytochemical, trace and mineral composition of Vernonia amygdalina leaves. International Journal of Biological & Pharmaceutical Research. 6(5): 393-399. [05] Atangwho I. J, Ebong P.E, Egbung G.E, Eteng M.U and Eyong E.U (2007a) Effect of Vernonia amygdalina Del. on liver function in alloxan-induced hyperglycaemic rats. Journal of Pharmacy and Bioresources4(1): 25-31 [06] Atangwho I. J, Ebong P. E, Eteng M.U, Eyong E.U and Obi A.U (2007b). Effect of Vernonia amygdalinadel leaf on kidney function of diabetic rats. Int. J. Pharmacol., 3: 143-148. [07] Izevbige E.B, Bryant T.L and Walker A. (2004). A novel natural inhibitor of extracellular signal regulated kinases and human breast cancer cell growth. Experimental Biol. Med. 229(2): 163-169. [08] Huffman, M. A (2003). Animal self-medication and ethno-medicine: Exploration and exploitation of medicinal properties of plants. Proceedings of the Nutrition Society, 62:371-381. [09] Guengerich, F .P., D. H. Kim and M. Iwasaki, (1991). Role of human cytochrome P-450 IIE1 in the oxidation of many low molecular weight cancer suspects.Chem. Res. Toxicol., 4(2): 168-179. [10] Teufelhofer, O., W. Parzefall, E. Kainzbauer, F. Ferk, C. Freiler, S. Knasmuller, L. Elbling, R. Thurman and R. Schulte-Hermann, (2005). Superoxide generation from Kupffer cells contributes to hepatocarcinogenesis: Studies on NADPH oxidase knockout mice. Carcinogenesis 26: 319-329. [11] Okafor P. N. and Ogbonna, U. I (2003). Nitrate and nitrite contamination of water sources and fruit juices marketed in South-Eastern Nigeria. J. Food. Comp. Anal. 16: 213-216. [12] Okafor P. N. and Nwaogbo E (2005). Determination of nitrate, nitrite and N-nitrosamines, cyanide and ascorbic acid content of fruit juices marketed in Nigeria. Afri. J. Biotech. 4(10): 1105-1108. [13] Okafor, P. N., O. Nwosu, J. Chukwu, J. Agbayi and E. N. Maduagwu, (2007). Occurrence of malondialdehyde and N- nitrosamines and their precursors in some Nigerian ice creams, yogurts, meat and fish species.Afr. J. Biochem. Res., 1(1): 001-005. [14] Griesenbeck, J. S., D. S. Michelle, C. H. John, R. S. Joseph, A. R. Antonio and D.B. Jean, (2009). Development of estimates of dietary nitrates, nitrites and nitrosamines for use with the short willet food frequency questionnaire.Nutr. J., 8(16): 1-9. [15] Domanska, K. and B. Kowalski, (2002). Effect of different storage conditions on N-nitrosamine content in Polish edible offals processed meat products. Bull. Ver. Inst. Pulawy 46: 317-324. [16] Proksch, E., 2001. Toxicological evaluation of nitrosamines in condoms. Int. J. Hyg. Environ. Publishers: New York. [17] Vogel. A. I. (1971). A textbook of practical organic Chemistry including qualitative organic analysis. Longman group limited, London.Pp 426. [18] Reitman S. and Frankel, S. (1957). A colorimetric method for the determination of SGOT and SGPT. Am. J. Cln. Path.28: 56-58. [19] Ellman, G. L. (1959). Tissue sulfhydryl groups.Arch. Biochem. Biophys. 82: 70–77. [20] Misra, H. P. and Fridovich (1972). The role of superoxide anion in the autooxidation of epinephrine and a simple assay of superoxide dismutase. J. Biol. Chem., 247: 3170-3175. [21] Cohen, G., Dembiee, D. and Marcus, J. (1970). Measuremment of catalase activity in tissues extracts. Anal.Biochem., 34: 30-38. [22] Ohkawa H, Ohishi N, and Yogi K, (1979). Assay for lipid peroxidation in animal tissues by thiobarbituric acid reaction. Annals of Biochemistry 95: 351–358. [23] Venukumar M. R., and Latha M.S. (2002). Antioxidant activity of Curculigoorchioides in carbon tetra chloride induced hepatopathy in rats. Indian J.Clin.Biochem.17:80-87. [24] Babalola O. O., Anetor J. I., and Adeniyi F. A. (2001). Amelioration of carbon tetrachloride induced hepatotoxicity of terpenoid extract from leaves of Vernonia amygdalina. Afr. J. Med. Sci. 30(1-2): 91-93. [25] Iwalokun, B. A.; Efedede, B. U.; Alabi-Sofunde, J. A.; Oduala, T.; Magbagbeola, O. A.; Akinwande, A. I.(2006).Hepatoprotective and antioxidant activities of Vernonia amygdalina on acetaminophen-induced hepatic damage on mice. Journal of Medicinal Food 9(4):524-30. [26] Adesanoye O. A., and Farombi E. O. (2009). Hepatoprotective effects of Vernonia amygdalina (astereaceae) in rats treated with carbon tetrachloride. Exp. Toxicol. Pathol. 62: 197-206. [27] Arhoghro E. M., Ekpo K. E., Anosike E. O., and Ibeh G. O. (2009). Effect of aqueous extract of bitter leaf (Vernonia amygdalina Del) on carbon-tetrachloride (CCl4) induced liver damage in albino wistar rats. Eur. J. sci. Res., 26:122-130 [28] Yakubu M. T., Akanji M. A., and Oladiji A.T. (2008). Alterations in serum lipid profile of male rats by oral administration of aqueous extract of Fadogia argrestis stem. Res. J. Med. Plant. 2: 66-73. [29] Gesquieve L, Loreau N, Minnich J. (1999). Oxidative stress leads to cholesterol accumulation in vascular smooth muscle cells. Free Radic Bio Med.27: 134–145. [30] Sharma V. and Singh M. (2012). Alterations induced by n-nitrosodimethylamine and ethanolic root extract of Operculina turpethumin serum lipid profile of male albino mice. Asian J. Pharm.Clin. Res., 5(3): 69-73 [31] Gillian-Daniel L. Donald, Paul W. Bates, Angie Tebon, and Alan D. Attie (2002). Endoplasmic reticulum localization of the low density lipoprotein receptor mediates presecretory degradation of apolipoprotein B. PNAS99(7): 4337–4342. [32] Ismail RSA, A. A. A. El-Megeid, and A. R. Abdel-Moemin, (2009). Carbon tetrachloride-induced liver disease in rats: the potential effect of supplement oils with vitamins E and C on the nutritional status,” German Medical Science 7: 1–10. [33] Matsuda K. (1994). ACAT inhibitors as anti-atherosclerotic agents: compounds and mechanisms. Med. Res. Rev. 14:271–305. [34] Akah P, Njoku O, Nwanguma A, and Akunyili D (2004). Effect of aqueous leaf extract of Vernonia amygdalina on blood glucose and triglyceride levels of alloxan-induced diabetic rats (Rattusrattus).Anim. Res. Int., 1: 90-94. [35] Ezekwe C. I., and Obioha O. (2001). Biochemical effects of Vernonia amygdalinaon rat liver microsome. Niger J. Biochem. Mol. Biol. 16: 1745-1798. [36] Pompella A, Romani A, Benditti M (1991). Comportilose of membrane protein thiols and lipid peroxidation of allyl alcohol hepatotoxicity. BiochemPharmacol, 41: 1225-59. [37] Usunobun U., Okolie N. P., Anyanwu O. G., AdegbegiA.J. and Egharevba M. E. (2015). Phytochemical screening and proximate composition of Annona muricata leaves. European Journal of Botany, Plant Science and Phytology 2(1): 18-28. [38] Zhao Y, Zhai D, Chen X, Yang J, Song X,Hui H, Yu Q, and Xing Y (2007). Ketoprofenglucuronidation and bile excretion in carbon tetrachloride and alpha – naphthylisothiocyanate induced hepatic injury in rats. Toxicol. 230(1-2): 145-150. [39] Kujawska, M.; Ignatowicz, E.; Murias, M.; Ewertowska, M.; Mikołajczyk, K. and Jodynis-Liebert, J. (2009). Protective Effect of Red Beetroot against carbon-tetrachloride and N-nitrosodiethylamine-induced oxidative stress in rats. J. Agric. Food Chem., 57: 2570–2575. [40] Farombi E. Olatunde, SangeetaShrotriya and Young-JoonSurh (2009). Kolaviron inhibits dimethylnitrosamine-induced liver injury by suppressing COX-2 and iNOS expression via NF-kb and AP-1. Life sciences 84:149-155. [41] Jin Y. L., Enzan H., Kuroda N., Hayashi Y., Nakayama H., Zhang Y. H., Toi M., Miyazaki E., Hiroi M, GuoL.M., and Saibara T. (2003). Tissue remodeling following submassive hemorrhagic necrosis in rat livers induced by an intraperitoneal injection of dimethylnitrosamine. Virchows Arch. 442:39–47 [42] Coen, M., Ruepp, S. U., Lindon, C. J., Nicholson, J. K., Pognan, F., Lenz, E. M., Wilson, I. D., (2004). J. Pharm. Biomed. Anal., 35, 93-105. [43] Farombi E. Olatunde, Sangeeta Shrotriya, Hye-Kyung Na, Sung-Hoon Kim, Young-JoonSurh (2008). Curcumin attenuates dimethylnitrosamine-induced liver injury in rats through Nrf2-mediated induction of hemeoxygenase-1. Food and Chemical Toxicology 46: 1279–1287. [44] Ojewole J. A. O. (2005). Antinociceptive, Anti-inflammatory and Anti-diabetic Effects of Bryophyllumpinnatum (Crassulaceae) Leaf Aqueous Extract. J. Ethnopharmacol. 99:13–19.