An antioxidant phytotherapy to rescue neuronal oxidative stress

Autophagy protects against cerebral ischemic reperfusion injury by inhibiting neuroinflammation

OBJECTIVE

To examine the effect of autophagy on cerebral damage caused by different models and test the hypothesis that its protection mechanism acts via inhibiting expression of neuroinflammatory mediators.

METHODS

Autophagy was induced by rapamycin treatment. Cerebral damage was induced using models of IL-6 treatment, oxygen glucose deprivation/reoxygenation (OGD/R) in vitro, and middle cerebral artery occlusion (MCAO) in vivo. The effect and mechanism of autophagy was examined and assessed in terms of cell viability, infarction size in brain tissue, neurological score, production of inflammatory mediators IL-1β and IL-6, transcription and protein expression of autophagy markers beclin-1 and LC-3II in different experimental groups.

RESULTS

Autophagy triggered by rapamycin could protect neurons from IL-6-induced injury and astrocytes from OGD/R-induced injury in vitro and in rat brain tissue from MCAO in vivo. Autophagy significantly increased cell viability, attenuated cerebral infarction and improved neurological scores. It also inhibited production of the IL-1β and IL-6 and elevated the expression of beclin-1 and LC-3II.

CONCLUSIONS

Autophagy can inhibit the inflammatory response and reduce cerebral I/R injury. There was a relationship between the extent of protection and (i) the level of the autophagic response, (ii) the stage of the cerebral I/R injury, and (iii) the time of intervention.

Traditional Oriental Medicines and Alzheimer's Disease

Alzheimer’s disease (AD), which is the most major cause of dementia, is a progressive neurodegenerative disease that affects cognitive functions. Even though the prevalence of AD is continuously increasing, few drugs including cholinesterase inhibitors and N-methyl D-aspartate-receptor antagonists were approved to treat AD. Because the clinical trials of AD drugs with single targets, such as β-amyloid and tau, have failed, the development of multi-target drugs that ameliorate many of the symptoms of AD is needed. Thus, recent studies have investigated the effects and underlying mechanisms of herbal formulae consisting of various herb combinations used to treat AD. This review discusses the results of clinical and nonclinical studies of the therapeutic efficacy in AD and underlying mechanisms of the herbal formulae of traditional Oriental medicines and bioactive compounds of medicinal plants.

Effect of Majun Baladur on life span, climbing ability, oxidative stress and dopaminergic neurons in the transgenic Drosophila model of Parkinson's disease

The effect of a poly herbal drug Majun Baladur (MB) was studied on the transgenic Drosophila melanogaster expressing human alpha synuclein in the neurons (PD flies). The equivalents of recommended dose for human were established for 20 g of fly food i.e. 0.0014, 0.0028, 0.0042 and 0.0056 g per 20 g of diet. The PD flies were allowed to feed on it for 24 days before performing the assays. The exposure to MB increased the life span and improves the activity of PD flies. The PD flies exposed to 0.0014, 0.0028, 0.042 and 0.0056 g of MB showed a dose dependent significant delay of 1.47, 1.88, 2.52 and 3.05 folds in the climbing ability compared to unexposed PD flies. A dose dependent significant decrease of 1.38, 1.45, 1.48 and 1.65 folds in TBARS; 1.08, 1.11, 1.17 and 1.20 folds in the GST activity; 1.20, 1.28, 1.39 and 1.52 folds in the PC content; 1.43, 1.53, 1.65 and 1.79 folds in the Caspase-9 activity; 1.21, 1.31, 1.53 and 1.64 folds in the activity of Caspase-3 and 1.24, 1.42, 1.50 and 1.79 folds in the activity of catalase; 1.50, 1.63, 1.88 and 2.06 folds in the activity of SOD in PD flies exposed to 0.0014, 0.0028, 0.042 and 0.0056 g of MB, respectively. A significant dose dependent increase of 1.20, 1.29, 1.33 and 1.44 folds in as NPSH content was observed in PD flies exposed to 0.0014, 0.0028, 0.042 and 0.0056 g of MB, respectively. The exposure to MB protects the loss of dopaminergic neurons as is evident by immunohistochemistry. It is concluded that MB is potent in reducing the PD symptoms being mimicked in the transgenic flies.

Enhancement in the Neuroprotective Power of Riluzole Against Cerebral Ischemia Using a Brain Targeted Drug Delivery Vehicle

Riluzole is the only available drug for motor neuron diseases quite well-known for its neuroprotective activity. But its poor aqueous solubility, short half-life with some side-effects at higher concentration poses a limitation to its use as a therapeutic agent. The present study was performed to investigate the therapeutic potential of nanoriluzole (NR), i.e., riluzole encapsulated in nanoparticles against cerebral ischemia (stroke) at three different concentrations [10 (NRL), 20 (NRM), and 40 (NRH) μg/kg body weight intraperitoneally (i.p.)]. Chitosan conjugated NIPAAM (N-isopropylacrylamide) nanoparticles coated with tween80 were synthesized through free radical polymerization. The particles were characterized with Transmission Electron Microscopy, Dynamic Light Scattering, and Fourier Transform Infrared spectroscopy and were found to have size of ∼50 nm. Cerebral ischemia was induced by Middle Cerebral Artery Occlusion (MCAO) model for 1 h and NR was given intraperitoneally after 1 h of MCAO. Animals were dissected after a reperfusion period of 24 h for evaluation of various parameters. Triphenyl tetrazolium chloride staining shows substantial reduction in infarct size in all three treated groups. It was also supported by histopathological results, biochemical parameters, and behavioral studies. Immunological parameters like NOS-2, NF-kB, and COX-2 also show profound reduction in expression in NR treated groups. Thus, the present work clearly demonstrated that the nanoparticle was good enough to carry large amount of drug across the Blood Brain Barrier which results in significant neuroprotection even at a very low concentration. It also substantially lowered the required concentration by overcoming the poor aqueous solubility; hence hardly leaving any scope for side-effects.

Environmental stimulation improves performance in the ox-maze task and recovers Na+,K+-ATPase activity in the hippocampus of hypoxic-ischemic rats

In animal models, environmental enrichment (EE) has been found to be an efficient treatment for alleviating the consequences of neonatal hypoxia-ischemia (HI). However the potential for this therapeutic strategy and the mechanisms involved are not yet clear. The aim of present study is to investigate behavioral performance in the ox-maze test and Na+,K+-ATPase, catalase (CAT) and glutathione peroxidase (GPx) activities in the hippocampus of rats that suffered neonatal HI and were stimulated in an enriched environment. Seven-day-old rats were submitted to the HI procedure and divided into four groups: control maintained in standard environment (CTSE), control submitted to EE (CTEE), HI in standard environment (HISE) and HI in EE (HIEE). Animals were stimulated with EE for 9 weeks (1 h/day for 6 days/week) and then behavioral and biochemical parameters were evaluated. Present results indicate learning and memory in the ox-maze task were impaired in HI rats and this effect was recovered after EE. Hypoxic-ischemic event did not alter the Na+,K+-ATPase activity in the right hippocampus (ipsilateral to arterial occlusion). However, on the contralateral hemisphere, HI caused a decrease in this enzyme activity that was recovered by EE. The activities of GPx and CAT were not changed by HI in any group evaluated. In conclusion, EE was effective in recovering learning and memory impairment in the ox-maze task and Na+,K+-ATPase activity in the hippocampus caused by HI. The present data provide further support for the therapeutic potential of environmental stimulation after neonatal HI in rats.

Evaluation on the Pharmacological Effect of Traditional Chinese Medicine SiJunZiTang on Stress-Induced Peptic Ulcers

Purpose. To explore the effects of SiJunZiTang (SJZT) on central neurotransmitters and the inhibition of HCl hypersecretion, along with the role of the vagus nerve. From this, the effects of SJZT and its constituent ingredients on inhibiting stress-induced peptic ulcers will be determined. Methods. Methods used to determine SJZT's effectiveness included (1) measuring the antipeptic ulcer effects of varying combinations of the constituents of SJZT; (2) evaluations of monoamine (MA) level in the brain; and (3) measuring the effects of longer-term SJZT treatment. Results. Comparing the control and experimental groups where the rats' vagus nerves were not cut after taking SJZT orally (500 mg/kg and 1000 mg/kg), the volume of enterogastric juice, free HCl and total acidity all reduce dose-dependently. The group administered SJZT at 1000 mg/kg showed significant reductions (P < 0.05). For the experimental groups where the vagus nerves were cut, a comparison with the control group suggests that the group receiving SJZT (500 mg/kg) orally for 21 days demonstrated a cure rate of 34.53%. Conclusion. The results display a correlation between the therapeutic effects of SJZT on stress-induced peptic ulcers and central neurotransmitter levels. Further to this, SJZT can inhibit the hypersecretion of HCl in the stomach, thus inhibiting stress-induced peptic ulcers.

Mitochondrial protection and anti-aging activity of Astragalus polysaccharides and their potential mechanism

The current study was performed to investigate mitochondrial protection and anti-aging activity of Astragalus polysaccharides (APS) and the potential underlying mechanism. Lipid peroxidation of liver and brain mitochondria was induced by Fe²⁺–Vit C in vitro. Thiobarbituric acid (TBA) colorimetry was used to measure the content of thiobarbituric acid reactive substances (TBARS). Mouse liver mitochondrial permeability transition (PT) was induced by calcium overload in vitro and spectrophotometry was used to measure it. The scavenging activities of APS on superoxide anion (O₂^•−) and hydroxyl radical (•OH), which were produced by reduced nicotinamide adenine dinucleotide (NADH)—N-Methylphenazonium methyl sulfate (PMS) and hydrogen peroxide (H₂O₂)–Fe²⁺ system respectively, were measured by 4-nitrobluetetrazolium chloride (NBT) reduction and Fenton reaction colorimetry respectively. The Na₂S₂O₃ titration method was used to measure the scavenging activities of APS on H₂O₂. APS could inhibit TBARS production, protect mitochondria from PT, and scavenge O₂^•−, •OH and H₂O₂ significantly in a concentration-dependent manner respectively. The back of the neck of mice was injected subcutaneously with D-galactose to induce aging at a dose of 100 mg/kg/d for seven weeks. Moreover, the activities of catalase (CAT), surperoxide dismutase (SOD) and glutathione peroxidase (GPx) and anti-hydroxyl radical which were assayed by using commercial monitoring kits were increased significantly in vivo by APS. According to this research, APS protects mitochondria by scavenging reactive oxygen species (ROS), inhibiting mitochondrial PT and increasing the activities of antioxidases. Therefore, APS has the effect of promoting health.

Protective effects of IL-4 on Bacillus Calmette-Guerin and lipopolysaccharide induced immunological liver injury in mice

OBJECTIVE

Mice injected with Bacillus Calmette-Guérin (BCG) were challenged with lipopolysaccharide (LPS) to induce inflammatory liver injury. This study was performed to explore the protective effects of interleukin (IL)-4 against liver injury induced by BCG and LPS in mice.

MATERIALS AND METHODS

Mice injected with BCG (125 mg/kg) were challenged with LPS (10 μg/kg) to induce the model of inflammatory liver injury. Half an hour after injection of LPS, mice were subcutaneously administered rmIL-4 at 5 and 0.5 μg/kg, respectively. Liver injury was evaluated by serum transaminase assay and H & E staining. Liver cytokine concentrations were determined by enzyme-linked immunosorbent assay, and intrahepatic cytokine and iNOS mRNA levels by reverse transcriptase polymerase chain reaction. Intrahepatic apoptosis was evaluated by terminal deoxynucleotidyl transferase mediated nick end labeling. NF-κB p65 and ERK signal pathway was detected by Western-blotting. NF-κB signal pathway was also detected by electrophoretic mobility shift assay.

RESULTS

IL-4 reduced the serum ALT, AST and LDH, alleviated the inflammatory cells infiltration, down regulated the expression of TNF-α, IL-1β, IFN-γ, IL-6 and iNOS mRNA in liver, and alleviated hepatic glutathione depletion (GSH). In addition, IL-4 displayed inhibition of extracellular signal-regulated kinase phosphorylation and NF-κB activation.

CONCLUSION

IL-4 may protect mice against BCG/LPS-induced immune liver injury, besides ERK and NF-κB signal pathways were involved in the effects.

Anti-inflammatory effects of Chinese medicinal herbs on cerebral ischemia

Abstracts

Recent studies have demonstrated the importance of anti-inflammation, including cellular immunity, inflammatory mediators, reactive oxygen species, nitric oxide and several transcriptional factors, in the treatment of cerebral ischemia. This article reviews the roles of Chinese medicinal herbs as well as their ingredients in the inflammatory cascade induced by cerebral ischemia. Chinese medicinal herbs exert neuroprotective effects on cerebral ischemia. The effects include inhibiting the activation of microglia, decreasing levels of adhesion molecules such as intracellular adhesion molecule-1, attenuating expression of pro-inflammatory cytokines such as interleukin-1β and tumor necrosis factor-α, reducing inducible nitric oxide synthase and reactive oxygen species, and regulating transcription factors such as nuclear factor-κB.

Neuroprotection Offered by Majun Khadar, a Traditional Unani Medicine, during Cerebral Ischemic Damage in Rats

Stroke results in damages to many biochemical, molecular and behavioral deficits. Present study provides evidence of the protective efficacy of a Unani herbal medicine, Majun Khadar (MK), against cerebral ischemia-induced behavioral dysfunctions and neurochemical alterations in the hippocampus (HIP). Transient focal cerebral ischemia was induced for 2 h followed by reperfusion for 22 h in a rat model. Rats were divided into four groups: sham, middle cerebral artery occluded (MCAO), drug sham (MK; 0.816 g kg(-1) orally for 15 days) and MK pre-treated ischemic group (MK + MCAO). Levels of enzymatic and non-enzymatic antioxidants were estimated in HIP along with behavioral testing. MK pre-treatment significantly (P < .05-.001) restored the activities of glutathione peroxidase (GP×), glutathione reductase (GR), glutathione S-transferase (GST) and decreased the level of lipid peroxidation (LPO) and H2O2 content in HIP in the MK + MCAO group which were severely altered in the MCAO group. The content of glutathione (GSH), total thiols (TT) and ascorbic acid (AsA) was significantly depleted in the MCAO group; pretreatment with MK was able to restore its levels. Also in the MK + MCAO group, significant (P < .5-.001) recovery in behavioral testing by rota rod and open-field activities was seen as compared with the MCAO group. MK alone did not show any change neither in the status of various antioxidants nor behavioral functions over sham values. Although detailed studies are required for the evaluation of exact neuroprotective mechanism of MK against cerebral ischemia these preliminary experimental findings conclude that MK exhibits neuroprotective effect in cerebral ischemia by potentiating the antioxidant defense system of the brain.