Microvesicles from quiescent and TGF-[beta]1 stimulated hepatic stellate cells: Divergent impact on hepatic vascular injury

This study evaluated the effect of microvesicles(MVs) from quiescent and TGF-[beta]1 stimulated hepatic stellate cells (HSC-MVs, TGF-[beta]1HSC-MVs) on H.sub.2 O.sub.2 -induced human umbilical vein endothelial cells (HUVECs) injury and CCl.sub.4 -induced rat hepatic vascular injury. HUVECs were exposed to hydrogen peroxide (H.sub.2 O.sub.2) to establish a model for vascular endothelial cell injury. HSC-MVs or TGF-[beta]1HSC-MVs were co-cultured with H.sub.2 O.sub.2 -treated HUVECs, respectively. Indicators including cell survival rate, apoptosis rate, oxidative stress, migration, invasion, and angiogenesis were measured. Simultaneously, the expression of proteins such as PI3K, AKT, MEK1+MEK2, ERK1+ERK2, VEGF, eNOS, and CXCR4 was assessed, along with activated caspase-3. SD rats were intraperitoneally injected with CCl.sub.4 twice a week for 10 weeks to induce liver injury models. HSC-MVs or TGF-[beta]1HSC-MVs were injected into the tail vein of rats. Liver and hepatic vascular damage were also detected. In H.sub.2 O.sub.2 -treated HUVECs, HSC-MVs increased cell viability, reduced cytotoxicity and apoptosis, improved oxidative stress, migration, and angiogenesis, and upregulated protein expression of PI3K, AKT, MEK1/2, ERK1/2, VEGF, eNOS, and CXCR4. Conversely, .sup.TGF-[beta]1 HSC-MVs exhibited opposite effects. CCl.sub.4 - induced rat hepatic injury model, HSC-MVs reduced the release of ALT and AST, hepatic inflammation, fatty deformation, and liver fibrosis. HSC-MVs also downregulated the protein expression of CD31 and CD34. Conversely, TGF-[beta]1HSC-MVs demonstrated opposite effects. HSC-MVs demonstrated a protective effect on H.sub.2 O.sub.2 -treated HUVECs and CCl.sub.4 -induced rat hepatic injury, while TGF-[beta]1HSC-MVs had an aggravating effect. The effects of MVs involve PI3K/AKT/VEGF, CXCR4, and MEK/ERK/eNOS pathways.