Fig. 5

Histopathological review of rat livers by LNPs and SNPs during the dosing and recovery periods. A H&E staining of the livers at the end of the dosing period. Rats were subjected to LNPs (L2, L5, L8) or SNPs (S2, S5, S8) at 2, 5, and 8 mg/kg for 14 consecutive days. Hepatic sinusoid expansion and hepatocyte polarity disorder were common in all treated samples. Focal lymphocyte infiltration (*) with brown-colored NPs deposition (arrowhead) was found to be more severe, with larger areas in LNPs livers than those by SNPs. LNPs can be distinctly observed with brown color in the individual Kupffer cells at the end of the dosing period (→). Slight lymphocyte infiltration along with mild fibrosis (#) and focal necrosis (red arrow) was found in the SNPs-treated groups. B H&E staining of rat livers at the end of the recovery period. LNPs- and SNPs-treated groups were allowed to recover for 28 days after the discontinuation of BSA@Cu_2−xS NPs and were named the L8-R and S8-R groups. Severe LNPs-induced lymphocyte infiltration in the liver remained at the end of the recovery period, while the liver fully recovered after SNPs discontinuation