Chemical Constituents And Effects On Acetaminophen-induced Acute Liver Injury Of Ficus Pandurata Hance

Ficus pandurata Hance is a medicinal food in Lingnan area,and is widely used in folk soup-making culture under the alias "Shui Zhao Ying",and its hepatoprotective effects are receiving more and more attention.It is of considerable significance to clarify the chemical composition and further explore the liver-protective activity of F.pandurata,which may lay a solid theoretical foundation for the further development and utilization of F.pandurata.In the present study,the chemical constituents of dried roots of F.pandurata were isolated and identified,and the effects of it on alleviating acetaminophen-induced acute liver injury were investigated in vitro and in vivo models.In this experiment,the crude extract was obtained by extracting the dried roots of F.pandurata with ethanol by soaking,and three phases were extracted by petroleum ether,ethyl acetate and n-butanol from small to large polarity.Extracts were separated by D101 macroporous resin,MCI resin,C18 or silica gel column chromatography and semi-preparative HPLC repeatedly to obtain pure compounds,and the chemical structures of these compounds were identified by spectroscopic techniques.Thirty-one compounds have been isolated and identified including two new compounds(1-2),which are linear benzofuranocoumarin ring-opening compounds;the known compounds are: five linear benzofuranocoumarin ring-opening compounds(3-5,9-10),three coumarins(6-8),five triterpenoids(11-15),three nor-sesquiterpenoids(17-19),three flavonoids(20-22)and three phenolic acid compounds(23-25),etc.Nor-sesquiterpenoids are found for the first time from this plant.An APAP-induced AML-12 hepatocyte injury model was established,the ethanolic extract of F.pandurata(FPH)and 31 compounds were initially screened for hepatoprotective activity using the MTT method,and the hepatoprotective effects of FPH and two active compounds,mandelic acid(MA)and derrone(DER),were investigated.The hepatoprotective effects were verified by measuring the hepatic function indexes,ATP content,membrane potential changes,NADH oxidase and ROS content in AML-12 hepatocytes.In an APAP-induced hepatocyte injury cell model,FPH,MA and DER were shown to inhibit apoptosis,restore hepatocyte function,scavenge intracellular harmful oxygen radicals and relieve mitochondrial oxidative stress,significantly restoring cell survival and effectively alleviating APAP-induced AML-12 hepatocyte injury.FPH and MA were administered to BALB/c mice by gavage and APAP was injected intraperitoneally to construct an animal model of acute liver injury,and the effects of F.pandurata on alleviating liver injury in mice were elucidated by calculating organ coefficients,observing pathological sections,detecting liver function indexes in serum and liver and antioxidant indexes in tissues,as well as assessing the expression levels of oxidative stress-related proteins.FPH and MA were set at low and high doses,and silymarin(SIL)was used as a positive control.It was found that the liver status of the mice treated with FPH and MA was improved to some extent,and the ALT,AST and γ-GT in serum and tissues were effectively reduced,which had obvious effects of scavenging harmful ROS,inhibiting oxidative stress,restoring normal liver function and normalizing liver tissue status,and finally alleviating the liver injury in mice.FPH and MA can upregulate Nrf2 and HO-1 expression,which showed that the action mechanism of hepatoprotective effect may related to the activation of Nrf2/HO-1 signaling pathway that consequently exert antioxidant effects.In the present study,the chemical composition of F.pandurata were isolated and identifted,and the hepatoprotective effects of F.pandurata were investigated using AML-12 cells and BALB/c mouse models.It is found that F.pandurata extract and the two active compounds were able to alleviate APAP-induced acute liver injury by inhibiting oxidative stress in liver tissue and cells.