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Aim: Pre‐eclampsia is a serious pregnancy‐specific disease with an incidence of 9.4%. MicroRNAs play a key role in regulating factors in pre‐eclampsia, but related research is still limited. This study aims to reveal the role and potential mechanisms of miR‐483 in pre‐eclampsia. Methods: miR‐483 was detected in venous blood, umbilical cord blood and placental tissue of pre‐eclampsia patients by Real‐time Quantitative polymerase chain reaction (qRT‐PCR). Insulin‐like growth factor (IGF1) and miR‐483 were detected by qRT‐PCR and western blot in endothelial progenitor cells isolated from fetal umbilical cord blood. miR‐483 was overexpressed and inhibited to detect changes of IGF1 and PI3K/Akt/mTOR pathway in endothelial progenitor cells by qRT‐PCR and western blot. Results: miR‐483 was downregulated in venous blood, umbilical cord blood and placental tissue of pre‐eclampsia patients. In endothelial progenitor cells, overexpression of miR‐483 inhibited the expression of IGF1, and inhibition of miR‐483 promoted the expression of IGF1. miR‐483 regulates the expression of PI3K, Akt, and mTOR in endothelial progenitor cells. Conclusion: miR‐483 is downregulated in pre‐eclampsia and regulates endothelial progenitor cells by targeting IGF1. miR‐483 is a potential alternative for diagnosing and treating pre‐eclampsia. [ABSTRACT FROM AUTHOR]

MicroRNAs (miRNAs) have been established to regulate skeletal muscle development in mammals. However, few studies have been conducted on the regulation of proliferation and differentiation of bovine myoblast cells by miRNAs. The aim of our study was to explore the function of miR‐483 in cell proliferation and differentiation of bovine myoblast. Here, we found that miR‐483 declined in both proliferation and differentiation stages of bovine myoblast cells. During the proliferation phase, the overexpression of miR‐483 downregulated the cell cycle–associated genes cyclin‐dependent kinase 2 (CDK2), proliferating cell nuclear antigen (PCNA) messenger RNA (mRNA), and the protein levels. At the cellular level, cell cycle, cell counting kit‐8, and 5‐ethynyl‐2´‐deoxyuridine results indicated that the overexpression of miR‐483 block cell proliferation. During differentiation, the overexpression of miR‐483 led to a decrease in the levels of the myogenic marker genes MyoD1 and MyoG mRNA and protein. Furthermore, the immunofluorescence analysis results showed that the number of MyHC‐positive myotubes was reduced. In contrast, the opposite experimental results were obtained concerning both proliferation and differentiation after the inhibition of miR‐483. Mechanistically, we demonstrated that miR‐483 target insulin‐like growth factor 1 (IGF1) and downregulated the expression of key proteins in the PI3K/AKT signaling pathway. Altogether, our findings indicate that miR‐483 acts as a negative regulator of bovine myoblast cell proliferation and differentiation. MicroRNA‐483 (miR‐483) inhibits bovine myoblast cell proliferation and differentiation by targeting insulin‐like growth factor 1 (IGF1) and downregulated the expression of key proteins in the PI3K/AKT signaling pathway. These results will provide an insight target in breeding strategies appealing to cattle industry. [ABSTRACT FROM AUTHOR]

ABSTRACT MicroRNAs (miRNAs) can regulate cellular differentiation processes by modulating multiple pathways simultaneously. Previous studies to analyze in vivo miRNA expression patterns in developing human limb cartilage tissue identified significant downregulation of miR-483 in hypertrophic chondrocytes relative to proliferating and differentiated chondrocytes. To test the function of miR-483 during chondrogenesis, lentiviral strategies were used to overexpress miR-483 during in vitro chondrogenesis of human bone marrow-derived mesenchymal stem cells (hBM-MSCs). While the in vivo expression patterns led us to hypothesize that miR-483 may enhance chondrogenesis or suppress hypertrophic marker expression, surprisingly, miR-483 overexpression reduced chondrocyte gene expression and cartilage matrix production. In addition, cell death was induced at later stages of the chondrogenesis assay. Mechanistic studies revealed that miR-483 overexpression resulted in downregulation of the TGF-β pathway member SMAD4, a known direct target of miR-483-3p. From these studies, we conclude that constitutive overexpression of miR-483 in hBM-MSCs inhibits chondrogenesis of these cells and does not represent an effective strategy to attempt to enhance chondrocyte differentiation and anabolism in this system in vitro. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:2369-2377, 2017. [ABSTRACT FROM AUTHOR]

ABSTRACT Cell engineering and bioprocess optimizations such as low temperature cultivation represent powerful tools to improve cellular performance and product yields of mammalian production cells. Besides monoclonal antibodies (mABs), novel biotherapeutic formats such as viral vectors will gain increasing importance. Here, we demonstrate that similar to Chinese hamster ovary (CHO) cells, product yields of recombinant adeno-associated virus (rAAV) producing HeLa cells can be markedly increased by low temperature cultivation. MicroRNAs (miRNAs) are small non-coding RNAs that critically regulate cell phenotypes. We thus investigated differential miRNA expression in response to mild hypothermia in CHO and HeLa production cells. We discovered miR-483 to be substantially up-regulated upon temperature down-shift in both cell types. Functional validation experiments revealed that introduction of miR-483 mimics led to a significant increase in both rAAV and mAB production in HeLa and CHO cells, respectively. Furthermore, inhibition of miR-483 up-regulation during mild hypothermia significantly decreased product yields, suggesting that miR-483 is a key regulator of cellular productivity in mammalian cells. In addition, miRNA target gene identification indicated that miR-483 might regulate genes directly involved in cellular survival and protein expression. Our results highlight that miR-483 is a valuable tool for product-independent engineering of mammalian production cells. Biotechnol. Bioeng. 2016;113: 830-841. © 2015 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]