Objective To explore the effects of astaxanthin on pressure injury wounds.Methods In vitro experiment:Fibroblasts were treated with different concentrations of astaxanthin and their proliferation activity was detected by CCK-8 assay.Subsequently,fibroblasts were induced by hypoxia/reoxygenation,and the optimal concentration of astaxanthin was administered.Then the intracellular reactive oxygen species(ROS)level was detected by DHE fluorescent probes and the mRNA expression level of TNF-α,IL-1β,IL-6,IL-10,TGF-β was evaluated by RT qPCR.In vivo experiment:to construct a pressure injury model,two circular magnets were symmetrically adsorbed on both sides of the mouse skin for 5 hours everyday.Subsequently,equal amounts of physiological saline,low-dose astaxanthin(10 mg/kg),and high-dose astaxanthin(20 mg/kg)were administered by gavage in groups.Wound images were taken regularly.After 7-day treatment,wound healing rates were counted and wound tissues were collected for histopathological staining.Results In vitro,the fluorescence intensity of DHE in the astaxanthin groups were reduced dramatically.The relative mRNA expression level of TNF-α,IL-1β,IL-6 in the astaxanthin group declined,and the level of TGF-β and IL-10 mRNA increased significantly(P<0.05).In vivo,the wound healing rate and the level of TGF-β,IL-10 in high-dose astaxanthin group increased significantly.The ROS content and the level of TNF-α,IL-1β and IL-6 dropped markedly in astaxanthin groups(P<0.05).Conclusions Astaxanthin can significanlty alleviate oxidative stress,mitigate inflammation,thus exerting a protective effect on pressure injury wounds.

Organic anion transporting polypeptide 1B1 and 1B3 (OATP1B1/3) as important uptake transporters play a fundamental role in the transportation of exogenous drugs and endogenous substances into cells. Rat OATP1B2, encoded by the gene, is homologous to human OATP1B1/3. Although OATP1B1/3 is very important, few animal models can be used to study its properties. In this report, we successfully constructed the S knockout (KO) rat model using the CRISPR/Cas9 technology for the first time. The novel rat model showed the absence of OATP1B2 protein expression, with no off-target effects as well as compensatory regulation of other transporters. Further pharmacokinetic study of pitavastatin, a typical substrate of OATP1B2, confirmed the OATP1B2 function was absent. Since bilirubin and bile acids are the substrates of OATP1B2, the contents of total bilirubin, direct bilirubin, indirect bilirubin, and total bile acids in serum are significantly higher in KO rats than the data of wild-type rats. These results are consistent with the symptoms caused by the absence of OATP1B1/3 in Rotor syndrome. Therefore, this rat model is not only a powerful tool for the study of OATP1B2-mediated drug transportation, but also a good disease model to study hyperbilirubinemia-related diseases.