Abstract: Objective To study the effects of astaxanthin on renal fibrosis and apoptosis induced by partial unilateral ureteral
obstruction (UUO) in rats. Methods Ninety-six male adult SD rats were randomized into 6 equal groups, namely the blank
control group, sham-operated group, UUO group, and astaxanthin group at high, medium, and low doses. Left ureteral
ligation was performed in UUO and astaxanthin groups, and two days before the operation, the rats in astaxanthin groups
were lavaged with 25, 50, or 100 mg/kg astaxanthin daily for 14 days, while the same volume of saline was given to rats in
UUO group and sham-operated group. Renal pathological in the rats was observed with HE staining, and the expression levels
of TGF-β1, SGK1, and CTGF in the left kidney were detected immunohistochemically; the expression level of Bcl-2 and Bax
were detected using Bcl-2 and Bax detection kits. Results Compared to UUO group, high- and medium-dose astaxanthin
groups showed obviously ameliorated renal pathologies and reduced expressions of TGF-β1, SGK1, and CTGF in the left
kidney with lessened renal cell apoptosis. Conclusion Astaxanthin can reduce UUO-induced renal fibrosis and renal cell
apoptosis, demonstrating the renoprotective effect of astaxanthin against renal fibrosis.