Cloning the sterol carrier protein 2 genes of Japanese toad （Bufo japonicus formosus） and Chinese toad （Bufo gargarizans） and its tissue expression analysis

In this study,to clarify the bioactive polypeptides included in the skins and secretions of Bufo,we screened the Japanese toad(Bufo japonicus formosus) skin cDNA library by colony polymerase chain reaction(PCR),and obtained a transcript of 1 075 bp consisting of 1 37 bp 5′ untranslated region(UTR),515 bp 3′ UTR and a 423 bp open reading frame(ORF) encoding a polypeptide of 140 amino acid residues(GenBank accession number: KF359945).Homolog analysis showed a 70%–96% homology with sterol carrier protein-2(SCP-2) present in other animals,which is implicated in lipid metabolism of other organisms.The gene SCP-2 of Chinese toad(B.gargarizans) was cloned from a first strand cDNA of Bufo skin(GenBank accession number: KF381341) via PCR,whose encoding polypeptide has only one amino acid difference from that of Japanese toad.Tissue distribution analysis showed that SCP-2 expressed in all organs tested,though in the liver and spleen it manifested lower expression than in other organs.These findings might indicate SCP-2 being one of the active ingredients in toad skin.These findings may in turn have implications for further drug development from traditional Chinese medicine sources.

Hepatic TRPC3 loss contributes to chronic alcohol consumption-induced hepatic steatosis and liver injury in mice

Emerging evidence discloses the involvement of calcium channel protein in the pathological process of liver diseases.Transient receptor potential cation channel subfamily C member 3(TRPC3),a ubiquitously expressed non-selective cation channel protein,controls proliferation,inflammation,and immune response via operating calcium influx in various organs.However,our understanding on the biofunction of hepatic TRPC3 is still limited.The present study aims to clarify the role and potential mechanism(s)of TRPC3 in alcohol-associated liver disease(ALD).We recently found that TRPC3 expression plays an important role in the disease process of ALD.Alcohol exposure led to a significant reduction of hepatic TRPC3 in patients with alcohol-related hepatitis(AH)and ALD models.Antioxidants(N-acetylcysteine and mitoquinone)intervention improved alcohol-induced suppression of TRPC3 via a miR-339-5p-involved mechanism.TRPC3 loss robustly aggravated the alcohol-induced hepatic steatosis and liver injury in mouse liver;this was associated with the suppression of Ca^(2+)/calmodulin-dependent protein kinase kinase 2(CAMKK2)/AMP-activated protein kinase(AMPK)and dysregulation of genes related to lipid metabolism.TRPC3 loss also enhanced hepatic inflammation and early fibrosis-like change in mice.Replenishing hepatic TRPC3 effectively reversed chronic alcohol-induced detrimental alterations in ALD mice.Briefly,chronic alcohol exposure-induced TRPC3 reduction contributes to the pathological development of ALD via suppression of the CAMKK2/AMPK pathway.Oxidative stress-stimulated miR-339-5p upregulation contributes to alcohol-reduced TRPC3.TRPC3 is the requisite and a potential target to defend alcohol consumption-caused ALD.