Limits...
Dantrolene enhances the protective effect of hypothermia on cerebral cortex neurons.

Xu SY, Hu FY, Ren LJ, Chen L, Zhou ZQ, Zhang XJ, Li WP - Neural Regen Res (2015)

Bottom Line: Results revealed that the combination of dantrolene and hypothermia increased neuronal survival and the mitochondrial membrane potential, and reduced intracellular active oxygen cytoplasmic histone-associated DNA fragmentation, and apoptosis.Furthermore, improvements in cell morphology were observed.The combined treatment enhanced these responses compared with either treatment alone.

View Article: PubMed Central - PubMed

Affiliation: Postdoctoral Workstation, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong Province, China ; Department of Brain Center, Shenzhen Key Laboratory of Neurosurgery, Shenzhen Second People's Hospital, Shenzhen University First Affiliated Hospital, Shenzhen, Guangdong Province, China.

ABSTRACT
Therapeutic hypothermia is the most promising non-pharmacological neuroprotective strategy against ischemic injury. However, shivering is the most common adverse reaction. Many studies have shown that dantrolene is neuroprotective in in vitro and in vivo ischemic injury models. In addition to its neuroprotective effect, dantrolene neutralizes the adverse reaction of hypothermia. Dantrolene may be an effective adjunctive therapy to enhance the neuroprotection of hypothermia in treating ischemic stroke. Cortical neurons isolated from rat fetuses were exposed to 90 minutes of oxygen-glucose deprivation followed by reoxygenation. Neurons were treated with 40 μM dantrolene, hypothermia (at 33°C), or the combination of both for 12 hours. Results revealed that the combination of dantrolene and hypothermia increased neuronal survival and the mitochondrial membrane potential, and reduced intracellular active oxygen cytoplasmic histone-associated DNA fragmentation, and apoptosis. Furthermore, improvements in cell morphology were observed. The combined treatment enhanced these responses compared with either treatment alone. These findings indicate that dantrolene may be used as an effective adjunctive therapy to enhance the neuroprotective effects of hypothermia in ischemic stroke.

No MeSH data available.


Related in: MedlinePlus

JC-1 fluorescence probe labeling and flow cytometry.The change in JC-1 fluorescence reflects mitochondrial membrane function and is used as an early indicator of apoptosis. (A) J-aggregates show red fluorescence at a high ΔΨm; (B) JC-1 monomer shows green fluorescence at a low ΔΨm. Scale bars: 50 μm. (C) The mean fluorescence intensity of J-aggregates (upper panel) and the JC-1 monomer (lower panel). ΔΨm: Mitochondrial membrane potential.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4590241&req=5

Figure 2: JC-1 fluorescence probe labeling and flow cytometry.The change in JC-1 fluorescence reflects mitochondrial membrane function and is used as an early indicator of apoptosis. (A) J-aggregates show red fluorescence at a high ΔΨm; (B) JC-1 monomer shows green fluorescence at a low ΔΨm. Scale bars: 50 μm. (C) The mean fluorescence intensity of J-aggregates (upper panel) and the JC-1 monomer (lower panel). ΔΨm: Mitochondrial membrane potential.

Mentions: The JC-1 assay kit (Beyotime) was used to assess ΔΨm, according to manufacturer's instructions. When ΔΨm is high, the JC-1 fluorescence probe accumulates in the mitochondrial matrix to form red fluorescent J-aggregates (λ ex: 520 nm; λ em: 590 nm) (Figure 2A). When ΔΨm is low, the JC-1 forms green fluorescent monomers (λ ex: 490 nm; λ em: 530 nm) (Figure 2B). The ratio of the green-red fluorescence (i.e. JC-1 monomers/J-aggregates) (Figure 2C) reflected the degree of mitochondrial damage, as previously reported (Gao et al., 2014).


Dantrolene enhances the protective effect of hypothermia on cerebral cortex neurons.

Xu SY, Hu FY, Ren LJ, Chen L, Zhou ZQ, Zhang XJ, Li WP - Neural Regen Res (2015)

JC-1 fluorescence probe labeling and flow cytometry.The change in JC-1 fluorescence reflects mitochondrial membrane function and is used as an early indicator of apoptosis. (A) J-aggregates show red fluorescence at a high ΔΨm; (B) JC-1 monomer shows green fluorescence at a low ΔΨm. Scale bars: 50 μm. (C) The mean fluorescence intensity of J-aggregates (upper panel) and the JC-1 monomer (lower panel). ΔΨm: Mitochondrial membrane potential.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4590241&req=5

Figure 2: JC-1 fluorescence probe labeling and flow cytometry.The change in JC-1 fluorescence reflects mitochondrial membrane function and is used as an early indicator of apoptosis. (A) J-aggregates show red fluorescence at a high ΔΨm; (B) JC-1 monomer shows green fluorescence at a low ΔΨm. Scale bars: 50 μm. (C) The mean fluorescence intensity of J-aggregates (upper panel) and the JC-1 monomer (lower panel). ΔΨm: Mitochondrial membrane potential.
Mentions: The JC-1 assay kit (Beyotime) was used to assess ΔΨm, according to manufacturer's instructions. When ΔΨm is high, the JC-1 fluorescence probe accumulates in the mitochondrial matrix to form red fluorescent J-aggregates (λ ex: 520 nm; λ em: 590 nm) (Figure 2A). When ΔΨm is low, the JC-1 forms green fluorescent monomers (λ ex: 490 nm; λ em: 530 nm) (Figure 2B). The ratio of the green-red fluorescence (i.e. JC-1 monomers/J-aggregates) (Figure 2C) reflected the degree of mitochondrial damage, as previously reported (Gao et al., 2014).

Bottom Line: Results revealed that the combination of dantrolene and hypothermia increased neuronal survival and the mitochondrial membrane potential, and reduced intracellular active oxygen cytoplasmic histone-associated DNA fragmentation, and apoptosis.Furthermore, improvements in cell morphology were observed.The combined treatment enhanced these responses compared with either treatment alone.

View Article: PubMed Central - PubMed

Affiliation: Postdoctoral Workstation, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong Province, China ; Department of Brain Center, Shenzhen Key Laboratory of Neurosurgery, Shenzhen Second People's Hospital, Shenzhen University First Affiliated Hospital, Shenzhen, Guangdong Province, China.

ABSTRACT
Therapeutic hypothermia is the most promising non-pharmacological neuroprotective strategy against ischemic injury. However, shivering is the most common adverse reaction. Many studies have shown that dantrolene is neuroprotective in in vitro and in vivo ischemic injury models. In addition to its neuroprotective effect, dantrolene neutralizes the adverse reaction of hypothermia. Dantrolene may be an effective adjunctive therapy to enhance the neuroprotection of hypothermia in treating ischemic stroke. Cortical neurons isolated from rat fetuses were exposed to 90 minutes of oxygen-glucose deprivation followed by reoxygenation. Neurons were treated with 40 μM dantrolene, hypothermia (at 33°C), or the combination of both for 12 hours. Results revealed that the combination of dantrolene and hypothermia increased neuronal survival and the mitochondrial membrane potential, and reduced intracellular active oxygen cytoplasmic histone-associated DNA fragmentation, and apoptosis. Furthermore, improvements in cell morphology were observed. The combined treatment enhanced these responses compared with either treatment alone. These findings indicate that dantrolene may be used as an effective adjunctive therapy to enhance the neuroprotective effects of hypothermia in ischemic stroke.

No MeSH data available.


Related in: MedlinePlus