In Vitro Effect of Octyl – Methoxycinnamate (OMC) on the Release of Gn-RH and Amino Acid Neurotransmitters by Hypothalamus of Adult Rats

A splice form of IGF-1, IGF-1Eb, is upregulated after exercise or injury. Physiological responses have been ascribed to the 24-amino acid COOH-terminal peptide that is cleaved from the NH3-terminal 70-amino acid mature IGF-1 protein. This COOH-terminal peptide was termed “mechano-growth factor” (MGF). Activities claimed for the MGF peptide included enhancing muscle satellite cell proliferation and delaying myoblast fusion. As such, MGF could represent a promising strategy to improve muscle regeneration. Thus, at our two pharmaceutical companies, we attempted to reproduce the claimed effect of MGF peptides on human and mouse muscle myoblast proliferation and differentiation in vitro. Concentrations of peptide up to 500 ng/ml failed to increase the proliferation of C2C12 cells or primary human skeletal muscle myoblasts. In contrast, all cell types exhibited a proliferative response to mature IGF-1 or full-length IGF-1Eb. MGF also failed to inhibit the differentiation of myoblasts into myotubes. To address whether the response to MGF was lost in these tissue culture lines, we measured proliferation and differentiation of primary mouse skeletal muscle stem cells exposed to MGF. This, too, failed to demonstrate a significant effect. Finally, we tested whether MGF could alter a separate documented in vitro effect of the peptide, activation of p-ERK, but not p-Akt, in cardiac myocytes. Although a robust response to IGF-1 was observed, there were no demonstrated activating responses from the native or a stabilized MGF peptide. These results call in to question whether there is a physiological role for MGF.

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In Vitro Effect of Salicylate on Amino-Acid Accumulation by Kidney Cortex Slices

Nature ◽

10.1038/200139a0 ◽

1963 ◽

Vol 200 (4902) ◽

pp. 139-141 ◽

Cited By ~ 9

Author(s):

STANTON SEGAL ◽

ALBERTA BLAIR

Keyword(s):

Amino Acid ◽

Kidney Cortex ◽

Acid Accumulation ◽

Cortex Slices ◽

Vitro Effect ◽

Kidney Cortex Slices ◽

Amino Acid Accumulation

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Regulation of retinal amino acid neurotransmitters by neuroprostanes and isoprostanes, in vitro and ex vivo

The FASEB Journal ◽

10.1096/fasebj.22.1_supplement.1126.3 ◽

2008 ◽

Vol 22 (S1) ◽

Author(s):

Catherine Atieno Opere ◽

Min Zhao ◽

Sunny E Ohia

Keyword(s):

Amino Acid ◽

Ex Vivo ◽

Amino Acid Neurotransmitters

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Follicle-stimulating hormone administration affects amino acid metabolism in mammalian oocytes†

Biology of Reproduction ◽

10.1093/biolre/ioz117 ◽

2019 ◽

Vol 101 (4) ◽

pp. 719-732 ◽

Cited By ~ 3

Author(s):

Anna Tetkova ◽

Andrej Susor ◽

Michal Kubelka ◽

Lucie Nemcova ◽

Denisa Jansova ◽

...

Keyword(s):

Protein Synthesis ◽

Amino Acid ◽

Follicle Stimulating Hormone ◽

Amino Acid Uptake ◽

Acid Uptake ◽

Fsh Receptor ◽

Cytoplasmic Maturation ◽

Vitro Effect ◽

Stimulating Hormone

Abstract Culture media used in assisted reproduction are commonly supplemented with gonadotropin hormones to support the nuclear and cytoplasmic maturation of in vitro matured oocytes. However, the effect of gonadotropins on protein synthesis in oocytes is yet to be fully understood. As published data have previously documented a positive in vitro effect of follicle-stimulating hormone (FSH) on cytoplasmic maturation, we exposed mouse denuded oocytes to FSH in order to evaluate the changes in global protein synthesis. We found that dose-dependent administration of FSH resulted in a decrease of methionine incorporation into de novo synthesized proteins in denuded mouse oocytes and oocytes cultured in cumulus-oocyte complexes. Similarly, FSH influenced methionine incorporation in additional mammalian species including human. Furthermore, we showed the expression of FSH-receptor protein in oocytes. We found that major translational regulators were not affected by FSH treatment; however, the amino acid uptake became impaired. We propose that the effect of FSH treatment on amino acid uptake is influenced by FSH receptor with the effect on oocyte metabolism and physiology.

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Influence of ketamine on amino acid neurotransmitters secretion by nerve cells in vitro

Bangladesh Journal of Pharmacology ◽

10.3329/bjp.v11is1.26411 ◽

2016 ◽

Vol 11 ◽

pp. S55-S60

Author(s):

Mingxian Shi ◽

Rui Chen ◽

Cen Guo ◽

Li Gao

Keyword(s):

Amino Acid ◽

Glutamic Acid ◽

Acid Concentration ◽

Excitatory Amino Acid ◽

Nerve Cells ◽

Amino Acid Neurotransmitters ◽

Different Doses ◽

Amino Acid Glycine

In order to study the influence of amino acid neurotransmitters secreted by the nerve cells after ketamine treatment, the nerve cells were cultured in vitro to exclude the interference of other factors in vivo and treated with three different doses of ketamine (1, 3 and 5 µg/mL). Then, the concentration of neuronal amino acid neurotransmitters was examined at 0, 15, 30, 45, 60, 90, 120 min after treatment. The trends of each amino acid concentration after ketamine treatment were nearly the same among the different treatment doses. After 15 min of adapting time, ketamine decreased the excitatory amino acid glutamic acid and aspartic acid concentration, and increased the concentration of the inhibitory amino acid glycine. Their concentrations showed a tendency to return approximately to the original level after 120 min.

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The chronic effect of pulsed 1800 MHz electromagnetic radiation on amino acid neurotransmitters in three different areas of juvenile and young adult rat brain

Toxicology and Industrial Health ◽

10.1177/0748233718798975 ◽

2018 ◽

Vol 34 (12) ◽

pp. 860-872

Author(s):

Nawal A Ahmed ◽

Nasr M Radwan ◽

Heba S Aboul Ezz ◽

Yasser A Khadrawy ◽

Noha A Salama

Keyword(s):

Amino Acid ◽

Young Adult ◽

Electromagnetic Radiation ◽

Mobile Phone ◽

High Performance ◽

Gamma Aminobutyric Acid ◽

Amino Acid Neurotransmitters ◽

Adult Rats ◽

Mobile Phone Use ◽

Neurological Effects

The extensive use of mobile phones worldwide has raised increasing concerns about the effects of electromagnetic radiation (EMR) on the brain due to the proximity of the mobile phone to the head and the appearance of several adverse neurological effects after mobile phone use. It has been hypothesized that the EMR-induced neurological effects may be mediated by amino acid neurotransmitters. Thus, the present study investigated the effect of EMR (frequency 1800 MHz, specific absorption rate 0.843 W/kg, power density 0.02 mW/cm2, modulated at 217 Hz) on the concentrations of amino acid neurotransmitters (glutamic acid, aspartic acid, gamma aminobutyric acid, glycine, taurine, and the amide glutamine) in the hippocampus, striatum, and hypothalamus of juvenile and young adult rats. The juvenile and young adult animals were each divided into two groups: control rats and rats exposed to EMR 1 h daily for 1, 2, and 4 months. A subgroup of rats were exposed daily to EMR for 4 months and then left without exposure for 1 month to study the recovery from EMR exposure. Amino acid neurotransmitters were measured in the hippocampus, striatum, and hypothalamus using high-performance liquid chromatography. Exposure to EMR induced significant changes in amino acid neurotransmitters in the studied brain areas of juvenile and young adult rats, being more prominent in juvenile animals. It could be concluded that the alterations in amino acid neurotransmitters induced by EMR exposure of juvenile and young adult rats may underlie many of the neurological effects reported after EMR exposure including cognitive and memory impairment and sleep disorders. Some of these effects may persist for some time after stopping exposure.

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