Low-Dose Thymoquinone: A Chance for Preventive Treatment Before Hepatic Encephalopathy Develops: An Experimental Rat Study

Objective: Thymoquinone (Nigella sativa), one of

the popular phytotherapy bioactive substances, is an antioxidant and

anti-inflammatory substance with known hepatoprotective activity. In

this study, we investigated whether thymoquinone has preventive effects

on the development of hepatic encephalopathy in rats with hepatic

encephalopathy model at two different doses.

Methods: Healthy albino Spraque-dawley rats were

randomized into 4 different groups: healthy negative control group,

positive control group in which hepatic encephalopathy was induced by

intraperitoneal thioacetamide 200 mg/kg, Thymoquinone 10 mg/kg and

Thymoquinone 20 mg/kg treatment groups. Thymoquinone was administered to

the thymoquinone treated groups by gavage for 14 days, and then a

hepatic encephalopathy model was induced with 200 mg/kg thioacetamide

for three days. All rats were subjected to locomotor activity tests

twice, once at the beginning and once at the end, and serum ammonium

levels were measured and compared to determine whether the hepatic

encephalopathy model occurred.

Results: While the baseline locomotor activity tests

of the groups included in the study were not statistically different,

the final locomotor activity tests were found to be statistically

significantly different (p<0.05). In the post-hoc analysis, it was

found that Thymoquinone 10 mg/kg group was statistically significantly

different (p<0.05) in most of the locomotor activity tests from the

positive control group in which hepatic encephalopathy model was

created, and on the contrary, it had similar results to the healthy

negative control group (p>0.05). Serum ammonium levels were lower in

both thymoquinone groups compared to the positive control group, but not

statistically differed (p>0.05).

Conclusion: Low dose Thymoquinone (10 mg/kg) group

had similar results with the healthy group in both locomotor activity

tests and serum ammonium levels. Thus, low dose Thymoquinone offers a

promising treatment opportunity within the scope of preventive medicine

for individuals at high risk of developing hepatic encephalopathy.