Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.4.24.64 (MPP)
 1,876 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Ghrelin is an endogenous ligand for the growth hormone secretagogue receptor (GHS-R) acting to stimulate growth hormone release. In the previous study, we have observed the neuroprotective effects of ghrelin on dopaminergic neurons in vivo in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine -treated Parkinson's disease mice. In order to illustrate the underlying mechanisms, in the present study, we conducted our experiment in vitro in 1-methyl-4-phenylpyridinium (MPP(+))-treated MES23.5 cells that could express GHS-R1a. Ten- to 1,000-micromol/L MPP(+) treatment caused decreased cell viability, with increased lactate dehydrogenase leakage. A 200-micromol/L MPP(+) treatment was chosen to do the further experiments. MES23.5 cells treated with 200 micromol/L MPP(+) showed decreased mitochondrial transmembrane potential, an elevated level of reactive oxidative species production and activation of caspase-3. Additionally, these cells also showed apoptotic morphological changes. Pretreatment with different doses of ghrelin (10(-12)-10(-7) mol/L) could abolish the MPP(+)-induced apoptotic changes in a dose-dependent manner. These results suggested that ghrelin could antagonize MPP(+)-induced apoptosis in MES23.5 cells. The protective effects of ghrelin involved the restoration of mitochondria function.
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PMID:Ghrelin antagonized 1-methyl-4-phenylpyridinium (MPP(+))-induced apoptosis in MES23.5 cells. 1905 22

Ghrelin, a 28-amino acid peptide, is an endogenous ligand for the growth hormone secretagogue (GHS) receptor. Our previous data showed that ghrelin could inhibit apoptosis in Parkinson's disease (PD) models both in vitro and in vivo. There is now growing evidence that oxidative stress has a critical role in the etiology of PD. And ghrelin was reported to possess anti-inflammatory, antioxidant effects. Dose ghrelin protect dopaminergic neurons by its antioxidant effect? In the present study, 1-methyl-4-phenylpyridinium (MPP(+)) was used to evaluate the possible antioxidant effects of ghrelin on MPP(+)-induced neurotoxicity in MES23.5 cells and the underlying mechanisms. Our results showed that MPP(+) significantly increased malonaldehyde (MDA) level and Bax/Bcl2 ratio, reduced the level of Cu-Zn superoxide dismutase (SOD) and catalase (CAT). Ghrelin protected MES23.5 cells against MPP(+)-induced neurotoxicity by reversing these changes. Furthermore, ghrelin pretreatment significantly inhibited MPP(+)-induced nuclear factor-kappaB translocation. These results suggest that the protective effects of ghrelin on MPP(+)-induced cytotoxicity may be ascribed to its antioxidative properties, and the modulation of nuclear factor-kappaB.
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PMID:Ghrelin prevents 1-methyl-4-phenylpyridinium ion-induced cytotoxicity through antioxidation and NF-kappaB modulation in MES23.5 cells. 1993 Dec 50