MicroRNA Regulation of Acute Lung Injury and Acute Respiratory Distress Syndrome.

The acute respiratory distress syndrome (ARDS), a severe form of acute lung injury (ALI), is a very common condition associated with critically ill patients, which causes substantial morbidity and mortality worldwide. Despite decades of research, effective therapeutic strategies for clinical ALI/ARDS are not available. In recent years, microRNAs (miRNAs), small non-coding molecules have emerged as a major area of biomedical research as they post-transcriptionally regulate gene expression in diverse biological and pathological processes, including ALI/ARDS. In this context, this present review summarizes a large body of evidence implicating miRNAs and their target molecules in ALI/ARDS originating largely from studies using animal and cell culture model systems of ALI/ARDS. We have also focused on the involvement of miRNAs in macrophage polarization, which play a critical role in regulating the pathogenesis of ALI/ARDS. Finally, the possible future directions that might lead to novel therapeutic strategies for the treatment of ALI/ARDS are also reviewed. J. Cell. Physiol. 231: 2097-2106, 2016. © 2016 Wiley Periodicals, Inc.

MicroRNAs as potential targets for progressive pulmonary fibrosis.

Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive and devastating disorder. It is characterized by alveolar epithelial cell injury and activation, infiltration of inflammatory cells, initiation of epithelial mesenchymal transition (EMT), aberrant proliferation and activation of fibroblasts, exaggerated deposition of extracellular matrix (ECM) proteins, and finally leading to the destruction of lung parenchyma. MicroRNAs (miRNAs) are endogenous small non-coding RNA molecules that post-transcriptionally regulate gene expression in diverse biological and pathological processes, including cell proliferation, differentiation, apoptosis and metastasis. As a result, miRNAs have emerged as a major area of biomedical research with relevance to pulmonary fibrosis. In this context, the present review discusses specific patterns of dysregulated miRNAs in patients with IPF. Further, we discuss the current understanding of miRNAs involvement in regulating lung inflammation, TGF-ß1-mediated EMT and fibroblast differentiation processes, ECM genes expression, and in the progression of lung fibrosis. The possible future directions that might lead to novel therapeutic strategies for the treatment of pulmonary fibrosis are also reviewed.

The mode of reproductive-derived Spink (serine protease inhibitor Kazal-type) action in the modulation of mammalian sperm activity.

The reproductive-derived serine protease inhibitor Kazal-type (Spink) has been identified in seminal plasma, and Spink-spermatozoa binding has been illustrated in many mammalian species including human. We used mice as experimental animal to study the mode of Spink action in the modulation of mammalian sperm activity. A Spink3-binding zone was cytochemically stained on the sperm head at apical hook separated from intact acrosome, whether the cells were capacitated or not. The Spink3-spermatozoa binding neither changed the population of cells in the uncapacitated, capacitated and acrosome-reacted status nor affected the capacitation-related protein phosphorylation and cell motility enhancement. Despite that, the Spink-spermatozoa interaction resulted in decreasing the intracellular calcium concentration ([Ca(2+)](i)) of the cell head and suppressing both the acrosome reaction induced by Ca(+2) ionophore A23187 and the cell fertility. Furthermore, Spink3 seen on the head of spermatozoa in the uterine cavity after coitus could be removed by the trypsin-like activity in the uterine fluid of oestrous females, and free Spink3 in the uterine cavity suppressed the protease activity. We integrated our data to shed light on the molecular mechanism of how Spink and its inhibiting protease are interplayed to modulate the activity of mammalian spermatozoa during their transit in the reproductive tract.

Purification and identification of transglutaminase from mouse coagulating gland and its cross-linking activity among seminal vesicle secretion proteins.

A 75-kDa protein secreted from mouse coagulating gland was purified to homogeneity by a series of isolation steps including ion exchange chromatography on a DEAE-Sephacel column and ion exchange high-performance liquid chromatography on a sulfopropyl column. It was identified to be Type IV transglutaminase (TG(4)), based on the establishment of N-terminal sequences by automated Edman degradation together with partial sequences by MS analysis. Its cross-linking activity was tested on the reduced sample of mouse seminal secretion which contained seven major monomer proteins tentatively designated as SVS I-VII. The enzyme was able to cross-link any of SVS I-III but failed to cross-link the other SVS proteins with a M(r) value less than 14 kDa. SVS I and SVS III showed comparable substrate activity, but were much weaker than SVS II during the TG(4) catalysis.