The most common medications for the treatment of zoonotic toxoplasmosis are pyrimethamine and sulfadiazine, which may cause serious undesirable side effects. Thus, there is an urgent need to develop novel therapeutics. Baicalein (BAI, C₁₅H₁₀O₅) has been shown to perform well against protozoan parasites including Leishmania and Cryptosporidium. In this study, the inhibition efficacy of BAI on Toxoplasma gondii was evaluated using plaque, invasion, and intracellular proliferation assays. BAI effectively inhibited T. gondii (half-maximum inhibitory concentration (IC₅₀)=6.457×10^-5 mol/L), with a reduced invasion rate (33.56%) and intracellular proliferation, and exhibited low cytotoxicity (half-maximum toxicity concentration (TC₅₀)=5.929×10^-4 mol/L). Further investigation using a mouse model shed light on the inhibitory efficacy of BAI against T. gondii, as well as the potential mechanisms underlying its anti-parasitic effects. The survival time of T. gondii-infected ICR mice treated with BAI was remarkably extended, and their parasite burdens in the liver and spleen were greatly reduced compared with those of the negative control group. Histopathological examination of live sections revealed effective therapeutic outcomes in the treatment groups, with no notable pathological alterations observed. Furthermore, alterations in cytokine levels indicated that BAI not only effectively suppressed the growth of T. gondii but also prevented excessive inflammation in mice. Collectively, these findings underscore the significant inhibitory efficacy of BAI against T. gondii, positioning it as a promising alternative therapeutic agent for toxoplasmosis.
Animals ; Toxoplasma/drug effects* ; Flavanones/therapeutic use* ; Mice ; Antiparasitic Agents/therapeutic use* ; Mice, Inbred ICR ; Toxoplasmosis/drug therapy* ; Female

Abstrac:Aim To study the effect of hydroxysafflor yellow A ( HYSA ) on the proliferation of vascular smooth muscle cells ( VSMCs) and the related molecu-lar mechanism. Methods The inhibitory effects of hydroxysafflor yellow A on VSMC proliferation was de-tected using cell culture, MTT assay, Western blot and immunohistochemical staining. Results The results showed that HYSA inhibited cell proliferation induced by PDGF in a dose-dependent (5,10,20,40 μmol· L-1 ) manner, reduced proliferating cell nuclear anti-gen ( PCNA ) expression and blocked PDGFR-MEK-ERK1/2 signaling pathway activated by PDGF in VSMCs. Conclusion HYSA inhibits VSMCs prolifer-ation via reducing the expression of PCNA and blocking signal transduction of MEK-ERK1/2 in VSMCs.

Objective To elucidate the effect of hydroxysafflor yellow A (HYSA) on the proliferation of vascular smooth muscle cells (VSMCs) and the related mechanism.Methods VSMCs derived from SD rats were treated with DMEC culture medium (Control),10 ng/ml PDGF (PDGF group),pretreatment with HYSA at different doses (1,5,10,20,40,60 μmol/L) for 24 h then cotreatment with PDGF.After 24 h,MTT assay,Western blot and immunohistochemical staining were performed to evaluate the inhibitory effects of HYSA on VSMCs proliferation.Results HYSA inhibited PDGF induced VSMCs proliferation in a dose-dependent manner,dowregulated proliferating cell nuclear antigen (PCNA) expression and blocked PDGF activated PDGFR-MEK-ERK1/2 signaling pathway.Conclusions HYSA inhibits VSMCs proliferation possibly via downregulating the expression of PCNA and blocking MEK-ERK1/2 signal transduction in VSMCs.