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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

Neuroprotective effect of human arginine decarboxylase (hADC) transduction against oxygen-glucose deprivation (OGD) and restoration injury. Astrocytes restored to normoxic glucose-supplied conditions after 4 hrs OGD. Cytotoxicity was assessed by the lactate dehydrogenase (LDH) assay. Data are expressed as mean of ± SD of the three different experiments performed from separate cell preparations, with triplicate determinations performed in each experiment. Asterisks indicate a p < 0.001.
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Fig4: Neuroprotective effect of human arginine decarboxylase (hADC) transduction against oxygen-glucose deprivation (OGD) and restoration injury. Astrocytes restored to normoxic glucose-supplied conditions after 4 hrs OGD. Cytotoxicity was assessed by the lactate dehydrogenase (LDH) assay. Data are expressed as mean of ± SD of the three different experiments performed from separate cell preparations, with triplicate determinations performed in each experiment. Asterisks indicate a p < 0.001.

Mentions: To mimic the ischemia-reperfusion injury in vivo, cells were restored to normoxic glucose-supplied conditions after 4 hrs of OGD (Figure 4). Cytotoxicity was measured by LDH leakage from the injured cells. Cytotoxicity gradually increased in a time-dependent manner for up to 10 hrs during restoration. Even in hADC-astrocytes, the restoration from OGD caused cytotoxicity in a time-dependent-manner; the extent of damage was much less than that in control astrocytes.Figure 4


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)

Neuroprotective effect of human arginine decarboxylase (hADC) transduction against oxygen-glucose deprivation (OGD) and restoration injury. Astrocytes restored to normoxic glucose-supplied conditions after 4 hrs OGD. Cytotoxicity was assessed by the lactate dehydrogenase (LDH) assay. Data are expressed as mean of ± SD of the three different experiments performed from separate cell preparations, with triplicate determinations performed in each experiment. Asterisks indicate a p < 0.001.
© Copyright Policy - open-access
Related In: Results  -  Collection

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

Fig4: Neuroprotective effect of human arginine decarboxylase (hADC) transduction against oxygen-glucose deprivation (OGD) and restoration injury. Astrocytes restored to normoxic glucose-supplied conditions after 4 hrs OGD. Cytotoxicity was assessed by the lactate dehydrogenase (LDH) assay. Data are expressed as mean of ± SD of the three different experiments performed from separate cell preparations, with triplicate determinations performed in each experiment. Asterisks indicate a p < 0.001.
Mentions: To mimic the ischemia-reperfusion injury in vivo, cells were restored to normoxic glucose-supplied conditions after 4 hrs of OGD (Figure 4). Cytotoxicity was measured by LDH leakage from the injured cells. Cytotoxicity gradually increased in a time-dependent manner for up to 10 hrs during restoration. Even in hADC-astrocytes, the restoration from OGD caused cytotoxicity in a time-dependent-manner; the extent of damage was much less than that in control astrocytes.Figure 4

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