Studies On The Anti-hepatic Fibrosis Mechanism Of Phycocyanin From Spirulina In Vitro And In Vivo

The morbidity of liver diseases is very high in China.Hepatic fibrosis is a necessary process for the aggravation of liver diseases.Prevention and treatment of hepatic fibrosis is an effective way to prevent aggravation of liver diseases.The activation of hepatic stellate cells(HSC)and the production of extracellular matrix such as collagen type ?(Co-?)are the key to the occurrence of hepatic fibrosis.In addition,gut microbiota and microbial-associated molecular patterns(MAMPs)can also reach the liver through the hepatic intestinal circulation,causing liver inflammation and promoting the development of hepatic fibrosis.Phycocyanin(PC)has a wide range of applications in medicine and food because of its antioxidant,anti-inflammatory,and immune-enhancing properties.Many studies have shown that PC has a hepatoprotective effect,but the mechanism by which PC alleviates hepatic fibrosis is not yet clear.In order to reveal the specific mechanism of PC against hepatic fibrosis and promote the precise application of PC,we explored the specific effects of PC on hepatic fibrosis in vitro and in vivo,and the role of gut microbiota in the process of PC alleviating hepatic fibrosisIn vitro,HSC-T6 was activated by lipopolysaccharide(LPS),and explored proliferation and apoptosis after PC intervention.The results indicated that 10,100,and 1000?g/mL PC showed a good inhibition rate of HSC-T6 after 48 h.The inhibition rate of 1000?g/mL PC to cells was more than 60%,which was dose-dependent.It was observed that PC could enter the cytoplasm of HSC-T6 by laser confocal microscopy.Under ordinary optical microscope,it was observed that PC intervention could make cells round and shrink.qRT-PCR showed that phycocyanin could promote expression of apoptosis-related protein Caspase3 and inhibit expression of collagen type ?(Co-?),a marker of hepatic fibrosis.Those results indicated that phycocyanin could inhibit proliferation of HSC,promote apoptosis of HSC,thus reduce the production of Co-? and other extracellular matrix,and alleviate fibrosisIn vivo,CCl4 was injected intraperitoneally to induce hepatic fibrosis in rats,and explored hepatic fibrosis state and changes of gut microbiota after PC intervention The results showed that 100 mg/kg PC significantly reduced the degree of CCl4 induced hepatic fibrosis in rats,reduced inflammatory infiltration and fibronection,and decreased the expression of hepatic fibrosis markers Co-? and alpha-smooth muscle actin(?-SMA).The results of 16S rRNA high-throughput sequencing showed that CCl4 increased abundance of Firmicutes and decreased abundance of Bacteroidetes,while PC decreased changes of the above microbiota caused by CCl4,and improved gut microbiota.In addition,CC14 reduced abundance of Bacteroides,Parabacteroides and Blautia,which had anti-inflammatory activity.PC intervention significantly increased abundance of Blautia,a probiotic with anti-inflammatory activity,and Allobaculum,a probiotic with gut barrier protection activity.It was indicated that PC could recover the disordered gut microbiota and reduce inflammation by regulating gut microbiota,so as to alleviate hepatic fibrosisIn conclusion,our results indicated that PC has the ability to alleviate hepatic fibrosis.On the one hand,PC can play an anti-fibrosis role by promoting the apoptosis of HSC and reducing the production of extracellular matrix such as Co-I,which is a marker of fibrosis.On the other hand,PC can alleviate the development of hepatic fibrosis by increasing abundance of probiotics with anti-inflammatory activity and decreasing inflammation.