• Journal of Life Science
• /
• v.24 no.12
• /
• pp.1356-1363
• /
• 2014

Ghrelin is a 28 amino acid orexigenic peptide hormone that is secreted predominantly by tX/A cells in the stomach, and it plays a major role in energy homeostasis. Activated ghrelin has an n-octanoyl group covalently linked to the hydroxyl group of the Ser3 residue, which is critical for its binding to the G-protein coupled growth hormone secretagogue receptor-1a (GHS-R1a). According to recent reports, both ghrelin and its receptor, GHS-R1a, are expressed by a variety of immune cells, including T- and B-lymphocytes, monocytes, and dendritic cells, and ghrelin stimulation of leukocytes provides a potent immunomodulatory signal controlling systemic and age-associated inflammation and thymic involution. Here, we report that ghrelin protected murine thymocytes from dexamethasone (DEX)-induced cell death both in vivo and in vitro. Subsequently, we explored the molecular mechanisms of the antiapoptotic effect of ghrelin. According to our experiments, ghrelin inhibited the expression of proapoptotic proteins via the regulation of glucocorticoid receptor (GR) phosphorylation. As a result, ghrelin inhibited the proapoptotic activation of proteins, such as Caspase-3, PARP, and Bim. These data suggest that ghrelin, through GHS-R, inhibits the pathway to apoptosis by regulation of the proapoptotic protein activation signal pathway. They provide evidence that blocking apoptosis is an essential function of ghrelin during the development of thymocytes.

• The Korean Journal of Pharmacology
• /
• v.29 no.1
• /
• pp.9-22
• /
• 1993

To evaluate the protective effects of calcium antagonists, oxygen radical scavengers and excitatory amino acid (EAA) antagonist on the ischemic brain damage, we induced in vitro ischemic condition (namely, lack of oxygen and glucose) to rat hippocampal slices. And the degree of ischemic damage was determined by assaying changes in biochemical parameters such as ATP content and lactate ralease, MDA production in the presence or absence of the various drugs. During experimental ischemia for up to 60 min, ATP content was decreased and the amount of lactate release was markedly increased time-dependently. By changing the reaction medium which contained oxygen and glucose those biochemical parameters were recovered. But the recovery was not complete in this experimental condition. In the same ischemic conditions verapamil and vitamine E prevented the decrease of ATP content and the increase of lactate release from the slices. And verapamil and diltiazem decreased MDA release to the reaction medium. Superoxide dismutase (SOD) and MK-801 (as EAA receptor antagonist) protected the decrease of ATP content and reduced MDA release in 20 min ischemic condition, but glutathione affected ATP content and lactate release at the same condition. When oxygen and glucose were resupplied for 20 min after ischemic condition, verapamil showed the protective effect on the changes of ATP content and lactate release, and vitamine E decreased lactate release (at 20 min ischemia) and MDA release (at 60 min ischemia). These results showed that calcium antagonist and vitamine E protect the ischemic biochemical changes from rat hippocampal slices and calcium antagonist is more potent than vitamine E to protect the ischemical brain damege.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.45 no.7
• /
• pp.966-972
• /
• 2016

We investigated that methanolic extracts of 20 kinds of seaweeds from Jeju Island for their antioxidant activities, acetylcholinesterase and ${\beta}$-secretase inhibitory activities, and neuronal survival in order to evaluate their potentials as anti-dementia agents. Ecklonia cava extracts had the highest total polyphenol content among the 20 seaweed extracts. The antioxidant activity of seaweed extracts was measured by using 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assay. It was found that Ecklonia kurome extracts had the highest ABTS scavenging activity ($IC_{50}=0.07{\pm}0.01mg/mL$). As a result, Ecklonia cava, Ecklonia kurome, and Myelophycus simplex extracts were found to be the most effective in terms of acetylcholinesterase inhibitory activity. In the ${\beta}$-secretase activity assay, Ecklonia cava and Ecklonia kurome extracts were effectively inhibited ($84.41{\pm}1.70%$ and $81.17{\pm}2.43%$, respectively). As expected, neuronal cell death induced by $H_2O_2$ in SH-SY5Y cells was diminished by Ecklonia cava, Ecklonia kurome, and Sargassum yezoense extracts. Taken together, these results showed that Ecklonia cava extract has potential anti-dementia activity, which suggests that it might provide an effective strategy for improving dementia.

• Journal of Physiology & Pathology in Korean Medicine
• /
• v.23 no.5
• /
• pp.969-973
• /
• 2009

Samul-tang (SMT), which was firstly described in (Hwajegukbang) Song dynasty, is well known remedy for blood diseases in Oriental medicine. SMT is traditional herbal-remedy composed of Rehmanniae Radix Preparat, Angelicae Gigantis Radix, Cnidii Rhizoma and Paeoniae Radix. Recently, SMT has known to have anti-oxidative action. However, the reports on anti-oxidantic action in neuroglial cells are rare. In addition, the exact mechanisms are unclear. For these reasons, we investigated the protective effects of SMT on cell death induced by oxidative stress using C6 glioma cells. In our results, SMT accelerated proliferation rates of C6 cells in vitro. In addition, levels of LDH release induced by oxidative stress were lowered by treatment with SMT. Finally, protective effects on cell death induced by chemicals such as paraquat and rotenone were observed. In conclusion, these results suggest the possibility to protect brain cell or neuronal cell from damage induced by oxidative stress.

• The Journal of Korean Medicine
• /
• v.26 no.3 s.63
• /
• pp.135-145
• /
• 2005

Objectives : This study investigated effect of Evodiae fructus water extract (EVOR) on apoptotic cell death induced by NaCN in SK-N-SH neuroblastoma cell lines. NaCN stimulates glutamate release which can activate glutamate receptors to initiate excitotoxic processes. This study examines the role of EVOR in mediating NaCN-induced cytotoxicity. Methods & Results : Cytotoxicity was assessed by measuring lactate dehydrogenase (LDH) in the culture media. NaCN(0.1mM) produced cytotoxicity following 12hrs of incubation. NaCN-induced cytotoxicity was partially blocked by EVOR. The treatment of EVOR in simultaneous exposure of cultures to NaCN provided complete protection against cytotoxicity. NaCN-induced cytotoxicity was found to inhibit DNA fragmentation, repaired by cell cycle and simultaneous exposure to NaCN, regenerated with neurite outgrowh by EVOR. These results indicate thaf damage by NaCN in neumnal cell cultures was repaired by EVOR, whereas NaCN-induced cytotoxicity is blocked Primarily by activation of anti-apoptosis. Conclusions : These results suggest that EVOR may be beneficial for the treatment of dementia and other degenerative problems of the central nervous system.

• The Journal of Internal Korean Medicine
• /
• v.30 no.1
• /
• pp.51-63
• /
• 2009

Background and Objective : The prospects for developing an anti-apoptotic natural component or a compound that exerts a neuroprotective effect with few or no side effects for the treatment of neurodegenerative disease appear favorable. In the present study, we evaluated the effects of the methanol extract of Phellodendri Cortex (PC extract) on 1-methyl-4-phenyl pyridinium($MPP^+$)-induced apoptosis in PC-12 cells. Materials and Methods : We used the methanol extract of Phellodendri Cortex (PC extract). PC-12 cells were cultured by RPMZ-1640. We found the PC extract's gene expression (Bax, Bcl-2) by using RT-PCR. We examined the PC extract's protein expression (Bcl-2, Bax, cytochrome c, poly (ADP-ribose) polymerase (PARP), caspase-3) by SDS-PAGE and Western blot. Results : Apoptosis in $MPP^+$-induced PC-12 cells was accompanied by an increased Bax/Bcl-2 ratio, release of cytochrome c to the cytosol and the activation of caspase-3. PC extract inhibited the down-regulation of Bcl-2 and the up-regulation of Bax, as well as the release of mitochondrial cytochrome c into the cytosol. In addition, PC extract attenuated caspase-3 activation and cleavage of poly (ADP-ribose) polymerase (PARP). Conclusion : These results suggest that the neuroprotective potentials of PC extract against $MPP^+$-induced apoptosis can be. at least partially, ascribed to its anti-apoptotic effects in PC-12 cells.

• Journal of Oriental Neuropsychiatry
• /
• v.20 no.2
• /
• pp.1-17
• /
• 2009

Objectives : Alzheimer's disease(AD) is the most common form of dementia, which is characterized by progressive deterioration of memory and higher cortical functions that ultimately results in total degradation of intellectual and mental activities. Nokyongdaebo-tang(Lurongdabutang) has been usually used for the treatment for the deficiency syndrome dementia and amnesia. This experiment was designed to investigate the effect of the Nokyongdaebo-tang(Lurongdabutang) hot water extract on pathological AD model. Methods : The effects of the Nokyongdaebo-tang(Lurongdabutang) hot water extract on cultured spinal cord cells induced by ${\beta}$-amyloid were investigated. The effects of the Nokyongdaebo-tan(Lurongdabutang) hot water extract on the memory deficit mice induced by scopolamine were investigated. Results : 1. ${\beta}$-amyloid treatment on cultured spinal cord cells increased both GFAP-staining intensity of astrocytes and caspase 3 immunoreactivity on cultured cells. Then, Nokyongdaebo-tang(Lurongdabutang) treatment reduced the labeling intensity for both GFAP and caspase 3 proteins in culture cells. 2. Scopolamine treatment into mice increased levels of GFAP-positive astrocytes and caspase 3-labeled cells of the hippocampal subfields dentate hilar region, CA3 and CA1 area. In vivo administration of Nokyongdaebo-tang(Lurongdabutang) attenuated labeling intensity for those two proteins in the same hippocampal areas. Similar effects were observed by the treatment of galanthamine, an inhibitor of acetylcholinesterase. Conclusions : This experiment shows that the Nokyongdaebo-tang(Lurongdabutang) may play a protective role in damaged neural tissues. Since neuronal damage seen in degenerative brains such as AD are largely unknown, the current data may provide possible insight into therapeutic strategies for AD treatments. Nokyongdaebo-tang(Lurongdabutang) might be effective for the prevention and treatment of AD.

• Korean Journal of Food Science and Technology
• /
• v.52 no.5
• /
• pp.427-434
• /
• 2020

This study was performed to compare nutritional compounds and physiological functions of five domestic and imported green tea cultivars at three time points. The five cultivars were compared for theanine, γ-aminobutyric acid, and catechin content by LC-MS/MS and HPLC. Furthermore, the five tea cultivars were functionally characterized with respect to antioxidant activity, brain cell protective effect, and inhibitions of α-glucosidase and HMG-CoA reductase activities. Among green tea cultivars, Chamnok had the highest content of catechins (198 mg/g DW), theanine (11.89 mg/g DW), and tannin (23.6 mg/g DW). Considering functional properties, Chamnok treatment resulted in the maximum viability of brain cells and reduced the cortisol content of SH-SY5Y cells. The inhibition of α-glucosidase and HMG-CoA reductase was the strongest following Chamnok treatment (72.9% and 69.8%, respectively). These results indicate that Chamnok could be optimal for consumption or favorable processing owing to its high nutritional compounds, such as theanine and catechin, and remarkable brain cell protective effects.

• Journal of Chest Surgery
• /
• v.39 no.10 s.267
• /
• pp.739-748
• /
• 2006

Background: The purpose of this study is to ascertain the neuroprotective effect of cyclosporin A on the 25-min surgical ischemia model in the spinal cords of rabbits with neuropathological correlation and histoimmunochemical analyses, Material and Method: Thirty-two New Zealand white rabbits were randomly divided into four groups: Rabbits were randomly divided into four groups: the control 12 group (n=8), the control 17 group (n=8), the cyclosporin Cs2 group (n=8), and the cyclosporin Cs7 group (n=8). The 12 group underwent a 25-min aortic cross- clamp without intervention and were sacrificed on the 2nd day postoperatively, while the 17 group underwent a 25- min of aortic cross-clamp without intervention and were sacrificed on the 7th day postoperatively. The Cs2 group received cyclosporin A (25 mg/kg) intravenously 15 min after the 25-min cross-clamp and were sacrificed on the End day postoperatively, while the Cs7 group received cyclosporin A (25 mg/kg) intravenously 15 min after the 25-min cross-clamp and were sacrificed on the 7th day postoperatively. The rabbits underwent 25-min surgical aortic cross-clamp. Neurologic functions were evaluated on the 2nd day and 7th postoperative day using Tarlov scoring system. After scoring neurologic function, all rabbits were sacrificed for histopathologic observation. Result: All rabbits survived the experimental procedure. The values of Tarlov score did not show any differences between the control and cyclosporin groups on the 2nd day. The scores of group Cs7 ($2.75{\pm}0.89$) were significantly higher than those of group 17 ($1.25{\pm}1.39$) on the 7th day (p<0,05). On the histologic exanminations, specimens of the spinal cord showed necrosis and apoptosis. The pathologic scores of group Cs7 ($1,0{\pm}0.53$) was less than those of group 17 ($2.13{\pm}1.36$, p<0.05). TUNEL staing showed apoptosis of the specimen in group 12 and Cs2 but there was no stastically significant difference between groups on the score. There were more overexpression of HSP70 and nNOS in cyclosporine group than in control group. Conclusion: We think that cyclosporin A may decrease neuronal cell death with induced upregulation of HSP70 against 25-min ischemia of the spiral cord in the rabbit.

• Clinical and Experimental Pediatrics
• /
• v.46 no.11
• /
• pp.1101-1106
• /
• 2003

Purpose : In vivo, minocycline appears to be neuroprotective. Thus, the neuroprotective effects of minocycline were studied in a rat brain cortical cell culture induced by hypoxia. Methods : Cultured cells from the brains of Sprague-Dawley rats were divided into two sets of groups : normoxia groups treated with 5% $CO_2$ and hypoxia groups treated with 1% $CO_2$. After several days of incubation, the control groups were not treated with minocycline, while the sample groups were treated with either 1 or $10{\mu}g/mL$ of minocycline. The damaged cells were observed under a microscope, while apoptosis was detected using a TUNEL assay control-stained with DAPI. Results : Among the normoxia groups, the control and sample groups treated with 1 and $10{\mu}g/mL$ of minocycline were all statistically significantly different from each other. Meanwhile, among the hypoxia groups, although the control was significantly different from the sample groups, there was no statistically significant difference between the sample groups. When comparing the normoxia and hypoxia groups, there was a statistically significant difference between the control groups and sample groups treated with $1{\mu}g/mL$ of minocycline, yet no significant difference between the sample groups treated with $10{\mu}g/mL$ of minocycline. Conclusion : Minocycline was found to be neuroprotective in normoxia and hypoxia induced rat brain cortical cell cultures.