Transfection of C6 glioma cells with glia maturation factor upregulates brain-derived neurotrophic factor and nerve growth factor: trophic effects and protection against ethanol toxicity in cerebellar granule cells
Glial cells play active roles in neuronal survival, as well as neuroprotection against toxic insult. Recent studies suggest that the brain protein glia maturation factor (GMF) is involved in intracellular signaling in glia. This study investigated whether or not GMF plays a role in the survival-promoting and neuroprotective functions of glia. C6 glioma cells were transfected in vitro with GMF utilizing an adenovirus vector. The transfected cells overexpressed GMF intracellularly, but did not secrete the protein. The conditioned medium (CM) was obtained from the GMF-transfected cells (CM-GMF) and tested on primary neuronal cultures, consisting of cerebellar granule cells (CGC). The CGC cultures were utilized because these cultures have a background level of cell death, and the survival-promoting, i.e. neurotrophic effect, of the CM could be tested. In addition, since CGC cultures are ethanol-sensitive (ethanol enhances neuronal death), the neuroprotective effect of the CM against ethanol-induced cell death was tested also. We demonstrated that the CM-GMF had an enhanced neurotrophic effect as well as an increased neuroprotective effect against ethanol-induced cell death compared to control CM obtained from untransfected C6 cells (CM-Mock) or CM obtained from cells transfected with an unrelated gene (CM-LacZ). Because neurotrophins have trophic and protective effects, we investigated whether GMF-transfection upregulated the expression of neurotrophins in C6 cells. RT-PCR verified that GMF-transfected C6 cells had increased mRNA levels for BDNF and NGF. Immunoblotting corroborated the RT-PCR results and indicated that CM-GMF contained greater concentrations of BDNF and NGF protein compared to CM-Mock and CM-LacZ. A soluble TrkB-IgG fusion protein, which selectively binds BDNF and prevents its binding to the neuronal TrkB receptor, eliminated the neurotrophic effect of CM-GMF; whereas anti-NGF antibody was ineffective in preventing this effect, suggesting that the neurotrophic effect was due to BDNF. On the other hand, both the TrkB-IgG fusion protein and anti-NGF reduced neuroprotection, suggesting that BDNF and NGF both contribute to the neuroprotective effect of CM-GMF. In conclusion, GMF upregulates the expression of BDNF and NGF in C6 cells, and these factors exert neurotrophic and neuroprotective functions on primary neurons.
Pharmacology, Toxicology and Pharmaceutical Science
3
10%
Biochemistry, Genetics and Molecular Biology
2
7%
Other
1
3%
Unknown
9
31%
Attention Score in Context
Attention Score in Context
This research output has an Altmetric Attention Score of 6. This is our high-level measure of the quality and quantity of online attention that it has received. This Attention Score, as well as the ranking and number of research outputs shown below, was calculated when the research output was last mentioned on 26 May 2015.
All research outputs
#7,405,506
of 34,054,827 outputs
Outputs from Brain Research
#2,063
of 12,053 outputs
Outputs of similar age
#13,495
of 59,352 outputs
Outputs of similar age from Brain Research
#12
of 76 outputs
Altmetric has tracked 34,054,827 research outputs across all sources so far. This one has received more attention than most of these and is in the 73rd percentile.
So far Altmetric has tracked 12,053 research outputs from this source. They typically receive a little more attention than average, with a mean Attention Score of 5.4. This one has gotten more attention than average, scoring higher than 72% of its peers.
Older research outputs will score higher simply because they've had more time to accumulate mentions. To account for age we can compare this Altmetric Attention Score to the 59,352 tracked outputs that were published within six weeks on either side of this one in any source. This one has gotten more attention than average, scoring higher than 61% of its contemporaries.
We're also able to compare this research output to 76 others from the same source and published within six weeks on either side of this one. This one has gotten more attention than average, scoring higher than 72% of its contemporaries.
