BACKGROUNDSilymarin is a natural flavonoid component isolated from the Silybum Marianum (Milk Thistle) plant with multiple pharmacological activities. We investigated its anti-fibrotic effect on the liver and demonstrated its role in activating hepatic progenitor stem cells during liver regeneration.METHODSHybrid polymeric protein nanoparticles were prepared by loading silymarin with an albumin-hyaluronic acid complex to achieve stem cell targeting and increase silymarin's bioavailability.RESULTSTEM, Zeta potential, DLS, UV-visible spectrophotometer, Fluorescence analysis, and FTIR verified the successful formation of nanoparticles and efficient encapsulation. In the present study, The liver fibrotic model was induced by the intraperitoneal injection of carbon tetrachloride, followed by the injection of silymarin NPs into mice twice a week for 4 weeks. We evaluated the expression of hepatic fibrosis markers such as (Collagen I, TGF-β1, SMAD3, and MMP-3) and hepatic progenitor stem cell activation markers such as (HNF1β, FOXl1, CD90, Vimentin, and CD105). The results showed that the targeted silymarin NPs caused significant suppression and downregulation of Collagen I, TGF-β, SMAD-3, and MMP-3 and upregulation of the hepatic progenitor stem cells markers HNF1β, FOXl1, CD90, Vimentin, and CD105. They also didn't induce expression of IL-6, IL-1β, and TNF-α, proving that they cause no signs of inflammation.CONCLUSIONThe novel point is that these results demonstrated that the targeted Silymarin NPs not only could efficiently alleviate CCl4-induced liver fibrosis more than using only free silymarin; by inhibiting the TGF-β/Smad-3 signaling pathway, but also could activate hepatic progenitor stem cells causing liver regeneration.