scholarly journals Amino acid misincorporation during high-level expression of mouse epidermal growth factor inEscherichia coli

1991 ◽  
Vol 19 (13) ◽  
pp. 3511-3516 ◽  
Author(s):  
Carol A. Scorer ◽  
Martin J. Carrier ◽  
Robert F. Rosenberger
Keyword(s):  
Amino Acid ◽  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Inescherichia Coli ◽  
High Level Expression ◽  
Epidermal Growth ◽  
High Level

scholarly journals Epidermal growth factor alleviates the negative impact of urea on frozen-thawed bovine sperm, but the subsequent developmental competence is compromised

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Rasoul Kowsar ◽  
Shahrzad Ronasi ◽  
Nima Sadeghi ◽  
Khaled Sadeghi ◽  
Akio Miyamoto
Keyword(s):  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Dna Fragmentation ◽  
Acrosome Reaction ◽  
Developmental Competence ◽  
Ros Production ◽  
Sperm Capacitation ◽  
Bovine Sperm ◽  
Epidermal Growth ◽  
High Level

AbstractUpon insemination, sperm cells are exposed to components of the female reproductive tract (FRT) fluids, such as urea and epidermal growth factor (EGF). It has been shown that both urea and EGF use EGF receptor signaling and produce reactive oxygen species (ROS) that are required at certain levels for sperm capacitation and acrosome reaction. We therefore hypothesized that during bovine sperm capacitation, a high level of urea and EGF could interfere with sperm function through overproduction of ROS. High-level urea (40 mg/dl urea is equal to 18.8 mg/dl of blood urea nitrogen) significantly increased ROS production and TUNEL-positive sperm (sperm DNA fragmentation, sDF) percentage, but decreased HOS test score, progressive motility, acrosome reaction and capacitation. The EGF reversed the negative effects of urea on all sperm parameters, with the exception of ROS production and DNA fragmentation, which were higher in urea-EGF-incubated sperm than in control-sperm. The developmental competence of oocytes inseminated with urea-EGF-incubated sperm was significantly reduced compared to the control. A close association of ROS production or sDF with 0-pronuclear and sperm non-capacitation rates was found in the network analysis. In conclusion, EGF enhanced urea-reduced sperm motility; however, it failed to reduce urea-increased sperm ROS or sDF levels and to enhance subsequent oocyte competence. The data suggests that any study to improve sperm quality should be followed by a follow-up assessment of the fertilization outcome.

Mechanical stresses induce paracrine β-2 microglobulin from cardiomyocytes to activate cardiac fibroblasts through epidermal growth factor receptor

2018 ◽  
Vol 132 (16) ◽  
pp. 1855-1874 ◽  
Author(s):  
Yang Li ◽  
Xiaoyi Zhang ◽  
Lu Li ◽  
Xiang Wang ◽  
Zhidan Chen ◽  
...  
Keyword(s):  
Epidermal Growth Factor Receptor ◽  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Cardiac Dysfunction ◽  
Cardiac Fibroblasts ◽  
Growth Factor Receptor ◽  
Pressure Overload ◽  
Dependent Manner ◽  
Epidermal Growth ◽  
High Level

By employing a proteomic analysis on supernatant of mechanically stretched cardiomyocytes, we found that stretch induced a significantly high level of β-2 microglobulin (β2M), a non-glycosylated protein, which is related to inflammatory diseases but rarely known in cardiovascular diseases. The present data showed that serum β2M level was increased in patients with hypertension and further increased in patients with chronic heart failure (HF) as compared with control group, and the high level of serum β2M level correlated to cardiac dysfunction in these patients. In pressure overload mice model by transverse aortic constriction (TAC), β2M levels in serum and heart tissue increased progressively in a time-dependent manner. Exogenous β2M showed pro-fibrotic effects in cultured cardiac fibroblasts but few effects in cardiomyocytes. Adeno-associated virus 9 (AAV9)-mediated knockdown of β2M significantly reduced cardiac β2M level and inhibited myocardial fibrosis and cardiac dysfunction but not cardiac hypertrophy at 4 weeks after TAC. In vitro, mechanical stretch induced the rapid secretion of β2M mainly from cardiomyocytes by activation of extracellular-regulated protein kinase (ERK). Conditional medium (CM) from mechanically stretched cardiomyocytes activated cultured cardiac fibroblasts, and the effect was partly abolished by CM from β2M-knockdown cardiomyocytes. In vivo, knockdown of β2M inhibited the increase in phosphorylation of epidermal growth factor receptor (EGFR) induced by TAC. In cultured cardiac fibroblasts, inhibition of EGFR significantly attenuated the β2M-induced the activation of EGFR and pro-fibrotic responses. The present study suggests that β2M is a paracrine pro-fibrotic mediator and associated with cardiac dysfunction in response to pressure overload.

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