## 4 Results
### Renoprotective Effects of MF on GM-Treated Rats  
Next, we asked how treatment with MF affected the biochemical changes induced by GM treatment. The concurrent administration of MF to the GM-treated rats at a dose of \begin{table}
\begin{tabular}{c c c c c c} \hline \hline  & **CL** & **GM** & **TQ** & **MF** & **\(p\)** \\  & **(_n = 5_)** & **(_n = 5_)** & **(_n = 5_)** & **(_n = 5_)** & \\ \hline \multicolumn{6}{c}{**Renal function**} \\ \hline \multirow{3}{*}{Creatinine (mg/dL)} & \multirow{3}{*}{0.65 \(\pm\) 0.05} & \multirow{3}{*}{2.25 \(\pm\) 0.46} & \multirow{3}{*}{0.70 \(\pm\) 0.14} & \multirow{3}{*}{1.58 \(\pm\) 0.55} & CL vs. GM \(<\) 0.001 * \\  & & & & GM vs. TG \(<\) 0.001 * \\  & & & & GM vs. MF \(=\) 0.073 \\  & & & & TQ vs. MF \(=\) 0.010 * \\ \hline \multirow{3}{*}{Urea (mg/dL)} & \multirow{3}{*}{73 \(\pm\) 1.3} & \multirow{3}{*}{148.31 \(\pm\) 21.16} & \multirow{3}{*}{74.37 \(\pm\) 4.14} & \multirow{3}{*}{126.86 \(\pm\) 25.16} & CL vs. GM \(<\) 0.001 * \\  & & & & GM vs. TG \(<\) 0.001 * \\  & & & & GM vs. MF \(=\) 0.183 \\  & & & & TQ vs. MF \(=\) 0.002 * \\ \hline \multicolumn{6}{c}{**Oxidative Stress status**} \\ \hline Glutathione & \multirow{3}{*}{106.51 \(\pm\) 5.07} & \multirow{3}{*}{76.79 \(\pm\) 14.22} & \multirow{3}{*}{111.88 \(\pm\) 8.97} & \multirow{3}{*}{104.80 \(\pm\) 5.01} & CL vs. GM \(=\) 0.002 * \\  & & & & GM vs. TG \(=\) 0.002 * \\  & & & & GM vs. MF \(=\) 0.003 * \\  & & & & TQ vs. MF \(=\) 0.162 \\ \hline \multirow{3}{*}{Superoxide dismutase (SOD) (ng/mL)} & \multirow{3}{*}{2.76 \(\pm\) 0.17} & \multirow{3}{*}{1.25 \(\pm\) 0.54} & \multirow{3}{*}{2.61 \(\pm\) 0.17} & CL vs. GM \(<\) 0.001 * \\  & & & & GM vs. TG \(=\) 0.001 * \\  & & & & GM vs. MF \(=\) 0.001 * \\  & & & & GM vs. MF \(=\) 0.001 * \\  & & & & TQ vs. MF \(=\) 0.969 \\ \hline \multirow{3}{*}{Malondialdehydedehyde (MDA) (ng/mL)} & \multirow{3}{*}{325.93 \(\pm\) 8.83} & \multirow{3}{*}{356.32 \(\pm\) 12.5} & \multirow{3}{*}{319.41 \(\pm\) 8.21} & \multirow{3}{*}{327.82 \(\pm\)15.04} & CL vs. GM \(=\) 0.002 * \\  & & & GM vs. TG \(=\) 0.001 * \\ \cline{1-1}  & & & GM vs. MF \(=\) 0.012 * \\ \hline \multicolumn{6}{c}{**means the _p_-value is significant (<0.05).**} \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Comparison of renal function and oxidative stress status between control (CL), gentamicin (GM), thymoquinone (TQ), and metformin (MF)-treated rats. Data expressed as Mean \(\pm\) SD. 60 mg/kg body weight daily for four successive weeks produced no significant differences in serum creatinine and urea (M \(\pm\) SD= 1.58 \(\pm\) 0.55 and 126.86 \(\pm\) 25.16 mg/dL) levels compared with those in the GM-treated rats (M \(\pm\) SD = 2.25 \(\pm\) 0.466 and 148.31 \(\pm\) 21.16 mg/dL for creatinine and urea, respectively; Table 1). Additionally, the administration of MF improved the oxidative buffering capacity in the rats treated with GM, as indicated by the significant increase in GLPX1 and SOD (M \(\pm\) SD = 104.80 \(\pm\) 5.01 and 2.61 \(\pm\) 0.13) compared with that in the GM-treated rats (M \(\pm\) SD = 76.79 \(\pm\) 14.22 and 1.25 \(\pm\) 0.54, respectively, \(p\) < 0.05) and the significantly reduced levels of tissue MDA (M \(\pm\) SD 327.82 \(\pm\) 15.04 ng/mL) compared with those in the GM-treated rats (M \(\pm\) SD = 356.32 \(\pm\) 12.5 ng/mL, \(p\) < 0.12; Table 1). The comparison of the TQ-treated rats with the metformin-treated rats revealed no significant differences regarding the oxidative buffering capacity, but the TQ-treated rats showed better renal function (M \(\pm\) SD = 0.70 \(\pm\) 0.14 and 74.37 \(\pm\) 4.14 mg/dL) than the metformin-treated rats (M \(\pm\) SD = 1.58 \(\pm\) 0.55 and 126.86 \(\pm\) 25.16 mg/dL with \(p\) < 0.5 for serum creatinine and urea; Table 1). These findings suggest that MF could reverse the biochemical changes induced by GM injections at the level of oxidative stress but did not reverse the changes in renal function with the drug dose and experimental conditions used for this study.