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Fish skin mucus is a dynamic barrier for invading pathogens with a variety of anti-microbial enzymes, including cyclophilin A (CypA), a multi-functional protein with peptidyl-prolyl cis/trans isomerase (PPIase) activity. Beside various other immunological functions, CypA induces leucocytes migration in vitro in teleost. In the current study, we have discovered several novel immune-relevant proteins in yellow catfish skin mucus by mass spectrometry (MS). The CypA present among them was further detected by Western blot. Moreover, the CypA present in the skin mucus displayed strong chemotactic activity for yellow catfish leucocytes. Interestingly, asparagine (like arginine in mammals) at position 69 was the critical site in yellow catfish CypA involved in leucocyte attraction. These novel efforts do not only highlight the enzymatic texture of skin mucus, but signify CypA to be targeted for anti-inflammatory therapeutics. [ABSTRACT FROM AUTHOR]

Obesity is a major risk for diabetes. Brown adipose tissue (BAT) mediates production of heat while white adipose tissue (WAT) function in the storage of fat. Roles of BAT in the treatment of obesity and related disorders warrants more investigation. Peroxisome proliferator activator receptor gamma (PPAR-γ) is the master regulator of both BAT and WAT adipogenesis and has roles in glucose and fatty acid metabolism. Adipose tissue is the major expression site for PPAR-γ. In this study, the effects of rosiglitazone on the brown adipogenesis and the association of MAPK and PI3K pathways was investigated during the in vitro adipogenic differentiation of telomerase transformed mesenchymal stromal cells (iMSCs). Our data indicate that 2 µM rosiglitazone enhanced adipogenesis by over-expression of PPAR-γ and C/EBP-α. More specifically, brown adipogenesis was enhanced by the upregulation of EBF2 and UCP-1 and evidenced by multilocular fatty droplets morphology of the differentiated adipocytes. We also found that rosiglitazone significantly activated MAPK and PI3K pathways at the maturation stage of differentiation. Overall, the results indicate that rosiglitazone induced overexpression of PPAR-γ that in turn enhanced adipogenesis, particularly browning adipogenesis. This study reports the browning effects of rosiglitazone during the differentiation of iMSCs into adipocytes in association with the activation of MAPK and PI3K signaling pathways. [ABSTRACT FROM AUTHOR]

MicroRNAs (miRNAs) play important roles in mediating multiple biological processes in eukaryotes and are being increasingly studied to evaluate their roles associated with cellular changes following viral infection. Snakehead fish Vesiculovirus (SHVV) has caused mass mortality in snakehead fish during the past few years. To identify specific miRNAs involved in SHVV infection, we performed microRNA deep sequencing on a snakehead fish cell line (SSN-1) with or without SHVV infection. A total of 205 known miRNAs were identified when they were aligned with the known zebrafish miRNAs, and nine novel miRNAs were identified using MiRDeep2 software. Eighteen and 143 of the 205 known miRNAs were differentially expressed at three and 24 h post-infection (poi), respectively. From the differentially-expressed miRNAs, five were randomly selected to validate their expression profiles using quantitative reverse transcription polymerase chain reaction (qRT-PCR), and their expression profiles were consistent with the microRNA sequencing results. In addition, the target gene prediction of the SHVV genome was performed for the differentially-expressed host miRNAs, and a total of 10 and 58 differentially-expressed miRNAs were predicted to bind to the SHVV genome at three and 24 h poi, respectively. The effects of three selected miRNAs (miR-130-5p, miR-214 and miR-216b) on SHVV multiplication were evaluated using their mimics and inhibitors via qRT-PCR and Western blotting. The results showed that all three miRNAs were able to inhibit the multiplication of SHVV; whereas the mechanisms underlying the SHVV multiplication inhibited by the specific miRNAs need to be further characterized in the future.