no significant change was observed in the grade of steatosis of the liver. Conclusions The current study described the effectiveness of a three-month consumption of NAC in patients with NAFLD, which resulted in a decrease in the level of ALT and in the size of the spleen, compared to those patients taking vitamin C. To our knowledge, few studies have been carried out to examine the implication of NAC on liver function in patients with NAFLD, and in particular on liver hemodynamics. Macrovesicular steatosis in the absence of significant alcohol consumption is the main characteristic of NAFLD, as a spectrum of liver diseases. This condition may be a precursor of NASH which has been found to lead to progressive fibrosis and cirrhosis. Impaired cellular function has contributed to oxidative stress leading to cellular death and hepatic necrosis caused by free radicals (11, 12). This impaired cellular function can be traced by liver function tests, which may even be the only indicator, up until the point of serious liver damage. Antioxidant supplements may protect cellular structures against oxidative stress. Such studies have been carried out by investigating the therapeutic interventions for NAFLD and NASH against oxidative stresses, but so far there has been no consensus about the therapeutic benefits (13). The present study evaluates the therapeutic effect of NAC on patients with NAFLD compared to Vitamin C, as well as, for the first time, on hemodynamic parameters. The ability of NAC to block the propagation of lipid peroxidation is reflected in the prevention of the onset of NAFLD by means of oral administration of S-nitroso-N-acetylcysteine in rats (14) and in the improvement of liver histology in rats with NASH after NAC treatment (9) However, the dietary addition of NAC is reported to have the same effect as diet alone and can improve the liver histopathology of NASH (15). The clinical features of NASH and NAFLD are very similar, and there is no non-invasive tool for a definite diagnosis. We have tried to compensate for the nonattendance for a liver biopsy (for ethical reasons) by selecting patients with NAFLD who had elevated liver enzymes in order to obtain a sample more similar to that found in patients with NASH. Such a condition is believed to have a clinically significant risk of developing end-stage liver disease (16). NAC can only decrease the serum level of ALT. Manouchehr Khoshbaten et al. 15 The relationship between ALT and NAFLD has not been completely explained, but studies support a higher level of ALT as not only a consequence but also a predictor of the development of NASH in these patients (17). Thus decreasing the level of ALT may be the best effect that it is possible to achieve. The present study has evaluated the effects of antioxidants on ultrasonographic features of liver function for the first time. Fatty change in the liver means enlargement of the hepatocytes containing fat droplets. This slows down the blood flow throughout the hepatic sinusoids and may result in the development of portal hypertension. A correlation has been noted between the degree of fatty infiltration in the liver, and the size of spleen (18). The current study suggests a decrease in the size of the spleen in NAFLD patients receiving NAC, which may reflect a reduction in fatty infiltration. These effects of NAC can be evaluated in detail by reviewing liver specimens after the intervention, and may be improved after a longer duration. In conclusion, a three-month supplement of NAC can alter ALT and the size of the spleen in patients with NAFLD, which is compatible with the improvement of fatty infiltration as has been shown in earlier studies. Acknowledgments Our research is supported by the Drug Applied Research Center at Tabriz University of Medical Sciences. References 1. Angulo P. Nonalcoholic fatty liver disease. N Engl J Med. 2002;346(16):1221-31. 2. Angulo P, Keach JC, Batts KP, Lindor KD. Independent predictors of liver fibrosis in patients with nonalcoholic steatohepatitis. Hepatology. 1999;30(6):1356-62. 3. Harrison SA, Torgerson S, Hayashi P, Ward J, Schenker S. Vitamin E and vitamin C treatment improves fibrosis in patients with nonalcoholic steatohepatitis. Am J Gastroenterol. 2003;98(11):2485-90. 4. Oliveira CP, Gayotto LC, Tatai C, et al. Vitamin C and vitamin E in prevention of Nonalcoholic Fatty Liver Disease (NAFLD) in choline deficient diet fed rats. Nutr J. 2003;2:9. 5. Attri S, Rana SV, Vaiphie K, et al. Protective effect of N-acetylcysteine in isoniazid induced hepatic injury in growing rats. Indian J Exp Biol. 2001;39(5):436-40. 6. Caglikulekci M, Dirlik M, Pata C, et al. Effect of N-acetylcysteine on blood and tissue lipid peroxidation in lipopolysaccharide-induced obstructive jaundice. J Invest Surg. 2006;19(3):175-84. 7. Huang H, Yin R, Zhu J, et al. Protective effects of melatonin and N-acetylcysteine on hepatic injury in a rat cardiopulmonary bypass model. J Surg Res. 2007;142(1):153-61. Hepatitis Monthly, Winter 2010; 10(1): 12-16