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Retroviral expression of human arginine decarboxylase reduces oxidative stress injury in mouse cortical astrocytes.

Hong S, Son MR, Yun K, Lee WT, Park KA, Lee JE - BMC Neurosci (2014)

Bottom Line: The neuroprotective effects of ADC seemed to be related to its ability to attenuate expression of iNOS and MMPs.Our findings imply that astrocytes can be reinforced against oxidative stress by endogenous agmatine production through ADC gene transduction.The results of this study provide new insights that may lead to novel therapeutic approaches to reduce cerebral ischemic injuries.

View Article: PubMed Central - PubMed

Affiliation: Brain Korea 21 Project for Medical Science, and Brain Research Institute, Department of Anatomy, Yonsei University College of Medicine, 50 Yonsei-ro, Seodaemun-gu, Seoul 120-752, Republic of Korea. jelee@yuhs.ac.

ABSTRACT

Background: In physiologic and pathologic conditions of the central nervous system (CNS), astrocytes are a double-edged sword. They not only support neuronal homeostasis but also contribute to increases in neuronal demise. A large body of experimental evidence has shown that impaired astrocytes play crucial roles in the pathologic process of cerebral ischemia; therefore, astrocytes may represent a breakthrough target for neuroprotective therapeutic strategies. Agmatine, an endogenous polyamine catalyzed from L-arginine by arginine decarboxylase (ADC), is a neuromodulator and it protects neurons/glia against various injuries.

Results: In this investigation, agmatine-producing mouse cortical astrocytes were developed through transduction of the human ADC gene. Cells were exposed to oxygen-glucose deprivation (OGD) and restored to a normoxic glucose-supplied condition. Intracellular levels of agmatine were measured by high performance liquid chromatography. Cell viability was evaluated by Hoechest/propidium iodide nuclear staining and lactate dehydrogenase assay. Expression of inducible nitric oxide synthase (iNOS) and matrix metalloproteinase s (MMPs) were assessed by a reverse transcription polymerase chain reaction, Western immunoblots, and immunofluorescence. We confirmed that ADC gene-expressed astrocytes produce a great amount of agmatine. These cells were highly resistant to not only OGD but also restoration, which mimicked ischemia-reperfusion injury in vivo. The neuroprotective effects of ADC seemed to be related to its ability to attenuate expression of iNOS and MMPs.

Conclusion: Our findings imply that astrocytes can be reinforced against oxidative stress by endogenous agmatine production through ADC gene transduction. The results of this study provide new insights that may lead to novel therapeutic approaches to reduce cerebral ischemic injuries.

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Related in: MedlinePlus

Astrocyte-protective effect of human arginine decarboxylase (hADC) transduction against oxygen-glucose deprivation (OGD). Cytotoxicity was assessed by Hoechst 33258 and propidium iodide (PI) nuclear staining; (A) No treatment control astrocytes, (B) astrocytes after 4 hrs OGD, (C) hADC-overexpressing astrocytes (hADC-astrocytes), (D) hADC-astrocytes after 4 hrs OGD. Scale bars = 100 μm. (E) Proportion of PI-labeled damaged cells with red fluorescence. Asterisks indicate a p < 0.05 when the samples were compared to no treatment control. Double asterisk indicate a p < 0.05 that that the two samples were significantly different which was confirmed by a post-hoc analysis.
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Fig3: Astrocyte-protective effect of human arginine decarboxylase (hADC) transduction against oxygen-glucose deprivation (OGD). Cytotoxicity was assessed by Hoechst 33258 and propidium iodide (PI) nuclear staining; (A) No treatment control astrocytes, (B) astrocytes after 4 hrs OGD, (C) hADC-overexpressing astrocytes (hADC-astrocytes), (D) hADC-astrocytes after 4 hrs OGD. Scale bars = 100 μm. (E) Proportion of PI-labeled damaged cells with red fluorescence. Asterisks indicate a p < 0.05 when the samples were compared to no treatment control. Double asterisk indicate a p < 0.05 that that the two samples were significantly different which was confirmed by a post-hoc analysis.

Mentions: OGD damaged naive astrocytes and the majority of cells had PI-labeled nuclei (Figure 3B). However, astrocytes overexpressing hADC (hADC-astrocytes) were much less damaged by OGD, and the proportion of PI-positive cells were considerably lower (Figure 3D). hADC transduction itself did not have any significant effects on cell viability (Figure 3C), as determined by Hoechst 33258 and PI double nuclear staining.Figure 3


Retroviral expression of human arginine decarboxylase reduces oxidative stress injury in mouse cortical astrocytes.

Hong S, Son MR, Yun K, Lee WT, Park KA, Lee JE - BMC Neurosci (2014)

Astrocyte-protective effect of human arginine decarboxylase (hADC) transduction against oxygen-glucose deprivation (OGD). Cytotoxicity was assessed by Hoechst 33258 and propidium iodide (PI) nuclear staining; (A) No treatment control astrocytes, (B) astrocytes after 4 hrs OGD, (C) hADC-overexpressing astrocytes (hADC-astrocytes), (D) hADC-astrocytes after 4 hrs OGD. Scale bars = 100 μm. (E) Proportion of PI-labeled damaged cells with red fluorescence. Asterisks indicate a p < 0.05 when the samples were compared to no treatment control. Double asterisk indicate a p < 0.05 that that the two samples were significantly different which was confirmed by a post-hoc analysis.
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC4150973&req=5

Fig3: Astrocyte-protective effect of human arginine decarboxylase (hADC) transduction against oxygen-glucose deprivation (OGD). Cytotoxicity was assessed by Hoechst 33258 and propidium iodide (PI) nuclear staining; (A) No treatment control astrocytes, (B) astrocytes after 4 hrs OGD, (C) hADC-overexpressing astrocytes (hADC-astrocytes), (D) hADC-astrocytes after 4 hrs OGD. Scale bars = 100 μm. (E) Proportion of PI-labeled damaged cells with red fluorescence. Asterisks indicate a p < 0.05 when the samples were compared to no treatment control. Double asterisk indicate a p < 0.05 that that the two samples were significantly different which was confirmed by a post-hoc analysis.
Mentions: OGD damaged naive astrocytes and the majority of cells had PI-labeled nuclei (Figure 3B). However, astrocytes overexpressing hADC (hADC-astrocytes) were much less damaged by OGD, and the proportion of PI-positive cells were considerably lower (Figure 3D). hADC transduction itself did not have any significant effects on cell viability (Figure 3C), as determined by Hoechst 33258 and PI double nuclear staining.Figure 3

Bottom Line: The neuroprotective effects of ADC seemed to be related to its ability to attenuate expression of iNOS and MMPs.Our findings imply that astrocytes can be reinforced against oxidative stress by endogenous agmatine production through ADC gene transduction.The results of this study provide new insights that may lead to novel therapeutic approaches to reduce cerebral ischemic injuries.

View Article: PubMed Central - PubMed

Affiliation: Brain Korea 21 Project for Medical Science, and Brain Research Institute, Department of Anatomy, Yonsei University College of Medicine, 50 Yonsei-ro, Seodaemun-gu, Seoul 120-752, Republic of Korea. jelee@yuhs.ac.

ABSTRACT

Background: In physiologic and pathologic conditions of the central nervous system (CNS), astrocytes are a double-edged sword. They not only support neuronal homeostasis but also contribute to increases in neuronal demise. A large body of experimental evidence has shown that impaired astrocytes play crucial roles in the pathologic process of cerebral ischemia; therefore, astrocytes may represent a breakthrough target for neuroprotective therapeutic strategies. Agmatine, an endogenous polyamine catalyzed from L-arginine by arginine decarboxylase (ADC), is a neuromodulator and it protects neurons/glia against various injuries.

Results: In this investigation, agmatine-producing mouse cortical astrocytes were developed through transduction of the human ADC gene. Cells were exposed to oxygen-glucose deprivation (OGD) and restored to a normoxic glucose-supplied condition. Intracellular levels of agmatine were measured by high performance liquid chromatography. Cell viability was evaluated by Hoechest/propidium iodide nuclear staining and lactate dehydrogenase assay. Expression of inducible nitric oxide synthase (iNOS) and matrix metalloproteinase s (MMPs) were assessed by a reverse transcription polymerase chain reaction, Western immunoblots, and immunofluorescence. We confirmed that ADC gene-expressed astrocytes produce a great amount of agmatine. These cells were highly resistant to not only OGD but also restoration, which mimicked ischemia-reperfusion injury in vivo. The neuroprotective effects of ADC seemed to be related to its ability to attenuate expression of iNOS and MMPs.

Conclusion: Our findings imply that astrocytes can be reinforced against oxidative stress by endogenous agmatine production through ADC gene transduction. The results of this study provide new insights that may lead to novel therapeutic approaches to reduce cerebral ischemic injuries.

Show MeSH
Related in: MedlinePlus