Temporal and regional changes of superoxide dismutase and glutathione peroxidase activities in rats exposed to focal cerebral ischemia

Effect of electroacupuncture on global cerebral ischemia-reperfusion injury in rats: A urine proteome analysis

BACKGROUND

This study aimed to investigate dynamic urinary proteome changes of electroacupuncture (EP) on cerebral ischemia-reperfusion (CI/R) injured rats and to explore the therapeutic biological mechanisms of EP.

METHODS

First, changed urinary proteins were found in EP stimulation in healthy rats. Then, we used a CI/R injury rat model induced by Pulsinelli's four-vessel occlusion (4-VO) method to explore the function of EP on urinary proteome in CI/R injury. Urine samples were collected for proteome analysis by liquid chromatography-tandem mass spectrometry (LC-MS/MS) and bioinformatics analysis.

RESULTS

In total, 384 proteins were identified, among which 47 proteins (23 upregulated, 24 downregulated) were differentially expressed with 0.6-log FC and p < .05. Gene ontology analysis revealed that the cell redox homeostasis, acute-phase response, response to lipopolysaccharide, and cellular response to glucocorticoid stimulus were significantly enriched. The partially biologically connected differential proteins were found by the Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis in the EP group. With the CI/R rat model, 80 proteins (27 upregulated, 53 downregulated) were significantly changed in the CI/R rats compared to the controls. Among these differentially expressed proteins (DEPs), 23 proteins (17 upregulated, six downregulated) showed significant changes after EP treatment (0.6-log FC change, p < .05). The main related biological processes were aging, immune response, acute-phase response, liver regeneration, protein catabolic process, and response to oxidative stress. Many metabolic pathways were enriched by KEGG analysis.

CONCLUSION

Our results indicate that the EP could alleviate cerebral damage induced by ischemia-reperfusion through an anti-inflammatory and metabolism regulation mechanism. The urinary proteome might reflect the pathophysiological changes in EP pretreatment in the treatment and prevention of CI/R injury.

Verapamil Inhibits Mitochondria-Induced Reactive Oxygen Species and Dependent Apoptosis Pathways in Cerebral Transient Global Ischemia/Reperfusion

The prefrontal cortex is the largest lobe of the brain and is consequently involved in stroke. There is no comprehensive practical pharmacological strategy for ameliorating prefrontal cortex injury induced by cerebral ischemia. Therefore, we studied the neuroprotective properties of verapamil (Ver) on mitochondrial dysfunction and morphological features of apoptosis in transient global ischemia/reperfusion (I/R). Ninety-six Wistar rats were allocated into four groups: control, I/R, I/R+Ver (10 mg/kg twice 1 hour prior to ischemia and 1 hour after reperfusion phase), and I/R+NaCl (vehicle). Animals were sacrificed, and mitochondrial dysfunction parameters (i.e., mitochondrial swelling, mitochondrial membrane potential, ATP concentration, ROS production, and cytochrome c release), antioxidant defense (i.e., superoxide dismutase, malondialdehyde, glutathione peroxidase, catalase, and caspase-3 activation), and morphological features of apoptosis were determined. The results showed that mitochondrial damage, impairment of antioxidant defense system, and apoptosis were significantly more prevalent in the I/R group in comparison with the other groups. Ver decreased mitochondrial damage by reducing oxidative stress, augmented the activity of antioxidant enzymes in the brain, and decreased apoptosis in the I/R neurons. The current study confirmed the role of oxidative stress and mitochondrial dysfunction in I/R progression and indicated the possible antioxidative mechanism of the neuroprotective activities of Ver.

Monocytes and monocyte chemoattractant protein 1 (MCP-1) as early predictors of disease outcome in patients with cerebral ischemic stroke

In this study to identify prognostic biomarkers for ischemic stroke (IS) outcome, we monitored monocyte number and monocyte chemoattractant protein (MCP-1) concentration in peripheral blood of 44 patients with IS during the week following IS. According to the severity of IS, patients were allocated to three groups: patients with transient ischemic attack (TIA), patients with National Institute of Health Stroke Scale (NIHSS) score ≤ 12, and patients with NIHSS > 12. In patients with NIHSS > 12 statistically significant increased number of monocytes was observed on day 7. MCP-1 plasma concentration initially increased, decreased at day 3 in patients with NIHSS > 12 and increased and restored on day 7. A negative correlation between the number of monocytes and MCP-1 concentration was observed on day 3 after IS. Higher day-7 MCP-1 level was associated with higher modified Rankin Scale (mRS) value (indicating worse outcome) at 90 days post-IS in patients with NIHSS > 12. Our findings suggest that number of monocytes and plasma MCP-1 level could be clinical prognostic biomarkers as early predictors of disease outcome in patients with IS.

Imaging of reactive oxygen species in focal ischemic mouse brain using a radical trapping tracer [(3)H]hydromethidine

Background

Reactive oxygen species (ROS) have been implicated in the pathophysiology of the brain after ischemic stroke. In this study, we investigate the generation of brain ROS after transient focal ischemia in mice using a radical trapping radiotracer, [³H]-labeled N-methyl-2,3-diamino-6-phenyl-dihydrophenanthridine ([³H]hydromethidine), which we recently reported as a ROS imaging probe. We also examined the effect of dimethylthiourea (DMTU), a hydroxyl radical scavenger, on brain ROS generation and infarct volume after transient focal ischemia in mice.

Methods

[³H]Hydromethidine was intravenously injected into mice at 1, 2, 5, and 7 h after transient middle cerebral artery occlusion (tMCAO), and then, the brain autoradiogram was acquired at 60 min after tracer injection. Brain infarct volumes at 24 h after tMCAO were assessed by 2,3,5-triphenyltetrazolium chloride staining.

Results

Accumulation of radioactivity was observed in the ipsilateral striatum and cortex at 1 h after tMCAO. The increase of radioactivity was attenuated at 2 h after tMCAO and then became maximized at 5 h. The high accumulation of radioactivity remained until 7 h after tMCAO. DMTU treatment significantly attenuated the accumulation of radioactivity in the ipsilateral hemisphere at 1, 5, and 7 h after tMCAO. Brain infarct volumes were also significantly reduced in DMTU-treated mice at 24 h after tMCAO.

Conclusions

These results indicated that [³H]hydromethidine is a useful radiotracer for detecting in vivo brain ROS generation such as hydroxyl radical after ischemic injury.

Effects of Astragaloside IV combined with the active components of Panax notoginseng on oxidative stress injury and nuclear factor-erythroid 2-related factor 2/heme oxygenase-1 signaling pathway after cerebral ischemia-reperfusion in mice

Background:

Astragalus and Panax notoginseng are traditional Chinese Medicines used for the treatments of ischemic cerebrovascular disease, being often combined together in China and achieving a good effect.

Objective:

The objective of this study is to investigate the effects of astragaloside-IV (AST-IV) (the effective component of Astragalus) combined with ginsenoside Rg1, ginsenoside Rb1, notoginsenoside R1 (the effective components of P. notoginseng) on oxidative stress injury after cerebral ischemia-reperfusion in mice, and to explore the mechanisms through nuclear factor-erythroid 2-related factor-2/heme oxygenase-1 (Nrf2/HO-1) signaling pathway.

Materials and Methods:

C57BL/6 mice were randomly grouped after treated for 3 days, the model of cerebral ischemia-reperfusion injury was established, and the brain tissues were detected.

Results:

AST-IV combined with ginsenoside Rg1, ginsenoside Rb1, notoginsenoside R1 could increase significantly the survival rate of nerve cell; decrease the contents of malondialdehyde, nitric oxide, increase the activity of superoxide dismutase and the level of glutathione; Nrf2 was down-regulated in the cytoplasm while up-regulated in nucleus, nuclear translocation rate raised as well as HO-1 messenger ribonucleic acid and protein expressions increased. The effects of four active components combination were better than those of the active components alone.

Conclusion:

Active components of Astragalus and P. notoginseng had the effects against cerebral ischemia-reperfusion injury, which were related to the antioxidative stress after cerebral ischemia-reperfusion. AST-IV combined with ginsenoside Rg1, ginsenoside Rb1, notoginsenoside R1 could strengthen the antagonism effects on ischemia-reperfusion and oxidative stress injury, the mechanism underlying might be associated with jointly activating Nrf2/HO-1 signaling pathway after cerebral ischemia-reperfusion.

Superoxide dismutase recombinant Lactobacillus fermentum ameliorates intestinal oxidative stress through inhibiting NF-κB activation in a trinitrobenzene sulphonic acid-induced colitis mouse model

AIMS

Superoxide dismutase (SOD) can prevent and cure inflammatory bowel diseases by decreasing the amount of reactive oxygen species. Unfortunately, short half-life of SOD in the gastrointestinal tract limited its application in the intestinal tract. This study aimed to investigate the treatment effects of recombinant SOD Lactobacillus fermentum in a colitis mouse model.

METHODS AND RESULTS

In this study, we expressed the sodA gene in Lact. fermentum I5007 to obtain the SOD recombinant strain. Then, we determined the therapeutic effects of this SOD recombinant strain in a trinitrobenzene sulphonic acid (TNBS)-induced colitis mouse model. We found that SOD activity in the recombinant Lact. fermentum was increased by almost eightfold compared with that in the wild type. Additionally, both the wild type and the recombinant Lact. fermentum increased the numbers of lactobacilli in the colon of mice (P < 0·05). Colitis mice treated with recombinant Lact. fermentum showed a higher survival rate and lower disease activity index (P < 0·05). Recombinant Lact. fermentum significantly decreased colonic mucosa histological scoring for infiltration of inflammatory cells, lipid peroxidation, the expression of pro-inflammatory cytokines and myeloperoxidase (P < 0·05) and inhibited NF-κB activity in colitis mice (P < 0·05).

CONCLUSIONS

SOD recombinant Lact. fermentum significantly reduced oxidative stress and inflammation through inhibiting NF-κB activation in the TNBS-induced colitis model.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study provides insights into the anti-inflammatory effects of SOD recombinant Lact. fermentum, indicating the potential therapeutic effects in preventing and curing intestinal bowel diseases.