MKP-1 modulates ubiquitination/phosphorylation of TLR signaling

Roles of ubiquitin‑specific protease 13 in normal physiology and tumors (Review)

Ubiquitin-specific protease 13 (USP13) is one of the most important deubiquitinases involved in various diseases. As deubiquitinases are components of the deubiquitination process, a significant post-translational modification, they are potential treatment targets for different diseases. With recent technological developments, the structure of USP13 and its pathological and physiological functions have been investigated. However, USP13 expression and function differ in various diseases, especially in tumors, and the associated mechanisms are complex and remain to be fully investigated. The present review summarized the recent discoveries and the current understanding of the USP13 function in tumors.

ANGPTL2 aggravates LPS-induced septic cardiomyopathy via NLRP3-mediated inflammasome in a DUSP1-dependent pathway

Angiopoietin-like protein 2 (ANGPTL2) was implicated in various cardiovascular diseases; however, its role in lipopolysaccharide (LPS)-related septic cardiomyopathy remains unclear. Herein, mice were exposed to LPS to generate septic cardiomyopathy, and adeno-associated viral vector was employed to overexpress ANGPTL2 in the myocardium. Besides, mice were treated with adenoviral vector to knock down ANGPTL2 in hearts. ANGPTL2 expressions in hearts and cardiomyocytes were upregulated by LPS challenge. ANGPTL2 overexpression aggravated, while ANGPTL2 silence ameliorated LPS-associated cardiac impairment and inflammation. Mechanically, we found that ANGPTL2 activated NLRP3 inflammasome via suppressing DUSP1 signaling, and NLRP3 knockdown abrogated the detrimental role of ANGPTL2 in aggravating LPS-induced cardiac inflammation. Furthermore, DUSP1 overexpression significantly inhibited ANGPTL2-mediated NLRP3 activation, and subsequently improved LPS-related cardiac dysfunction. In summary, ANGPTL2 exacerbated septic cardiomyopathy via activating NLRP3-mediated inflammation in a DUSP1-dependent manner, and our study uncovered a promising therapeutic target in preventing septic cardiomyopathy.

Antiviral immunity of grouper MAP kinase phosphatase 1 to Singapore grouper iridovirus infection

Singapore grouper iridovirus (SGIV), with various mechanisms for evading and modulating host, has inflicted heavy economic losses in the grouper aquaculture. MAP kinase phosphatase 1 (MKP-1) regulates mitogen-activated protein kinases (MAPKs) to mediate the innate immune response. Here, we cloned EcMKP-1, an MKP-1 homolog from the orange-spotted grouper Epinephelus coioides, and investigated its role in the infection of SGIV. In juvenile grouper, EcMKP-1 was highly upregulated and peaked at different times after injection with lipopolysaccharide, polyriboinosinic polyribocytidylic acid and SGIV. EcMKP-1 expression in heterologous fathead minnow cells was able to suppress SGIV infection and replication. Furthermore, EcMKP-1 was a negative regulator of c-Jun N-terminal kinase (JNK) phosphorylation early in SGIV infection. EcMKP-1 decreased the apoptotic percentage and caspase-3 activity during the late stage of SGIV replication. Our results demonstrate critical functions of EcMKP-1 in antiviral immunity, JNK dephosphorylation and anti-apoptosis during SGIV infection.

Beta-glucan enhanced immune response to Newcastle disease vaccine and changed mRNA expression of spleen in chickens

The present study was performed to investigate the effect of oral administration of β-glucan (G70), a product obtained from the cell wall of yeast, on Newcastle disease virus (NDV)-specific hemagglutination inhibition (HI) titers, lymphocyte proliferation, and the role of T lymphocyte subpopulations in chickens treated with live NDV vaccine. In addition, the influence of β-glucan on splenic gene expression was investigated by transcriptome sequencing. The results revealed that the supplementation of β-glucan boosted the titer of serum NDV HI increased the NDV stimulation index of lymphocytes in peripheral blood and intestinal tract, and promoted the differentiation of T lymphocytes into CD4⁺ T cells. The RNA sequencing (RNA-seq) analysis demonstrated that G70 upregulated the mRNA expressions related to G-protein coupled receptor and MHC class I polypeptide, and downregulated the mRNA expressions related to cathelicidin and beta-defensin. The immunomodulatory effect of G70 might function through mitogen-activated protein kinase signaling pathway. To sum up, G70 could boost the immunological efficacy of live NDV vaccine in chickens and could be applied as a potential adjuvant candidate in the poultry industry.