Possible role of vitamin E, coenzyme Q10 and rutin in protection against cerebral ischemia/reperfusion injury in irradiated rats

Therapeutic Effects of Coenzyme Q10 in the Treatment of Ischemic Stroke

PURPOSE OF REVIEW

Ischemic stroke is the second deadly disease worldwide, but current treatment is very limited. The brain, rich in lipids and high in oxygen consumption, is susceptible to damage from oxidative stress after ischemic stroke. Thus, antioxidants are promising neuroprotective agents for treatment and prevention of ischemic stroke. Coenzyme Q10 is the only lipophilic antioxidant that can be synthesized de novo by cells and plays a key role as an electron carrier in the oxidative phosphorylation of the mitochondrial electron transport chain. However, the reduced form of coenzyme Q10 (Ubiquinol) levels are significantly deficient in the brain. The aim of this article is to review the therapeutic effects and mechanisms of coenzyme Q10 in ischemic stroke.

RECENT FINDINGS

Current studies have found that coenzyme Q10 protects and treats ischemic stroke through multiple mechanisms based on the evidence from in vitro experiments, in vivo experiments, and clinical observations. For the first time, we reviewed the neuroprotective effects of coenzyme Q10 in ischemic stroke. Coenzyme Q10 exerts neuroprotective effects after ischemic stroke through anti-oxidative stress, anti-nitrosative stress, anti-inflammation, and anti-cell death. Here, we provided the evidence on the therapeutic and preventive effects of coenzyme Q10 in ischemic stroke and suggested the potential value of coenzyme Q10 as a medication candidate.

Cell Rearrangement and Oxidant/Antioxidant Imbalance in Huntington's Disease

Huntington's Disease (HD) is a hereditary neurodegenerative disorder caused by the expansion of a CAG triplet repeat in the HTT gene, resulting in the production of an aberrant huntingtin (Htt) protein. The mutant protein accumulation is responsible for neuronal dysfunction and cell death. This is due to the involvement of oxidative damage, excitotoxicity, inflammation, and mitochondrial impairment. Neurons naturally adapt to bioenergetic alteration and oxidative stress in physiological conditions. However, this dynamic system is compromised when a neurodegenerative disorder occurs, resulting in changes in metabolism, alteration in calcium signaling, and impaired substrates transport. Thus, the aim of this review is to provide an overview of the cell's answer to the stress induced by HD, focusing on the role of oxidative stress and its balance with the antioxidant system.

Tailoring of chitosan/diacrylated pluronic system as a versatile nanoplatform for the amelioration of radiation-induced cognitive dysfunction

Rutin (RUT) is a biologically active flavonoid that is reported to modulate radiation-induced brain dysfunctions. However, RUT's poor water solubility and low brain bioavailability limit its clinical use. To increase its brain bioavailability, RUT was loaded onto nanoplatforms based on chitosan/diacrylated pluronic (CS/DA-PLUR) nanogels synthesized by gamma radiation. The optimized formulation was investigated as a carrier system for RUT. Based on pilot experiments' results, the cranial radiation (CR) dose that induced cognitive dysfunction was selected. In the main experiment, rats were pre-treated orally with either free RUT or RUT-CS/DA-PLUR. Rats' cognitive and motor functions were assessed; 24 h later, rats were sacrificed, and the whole brain was separated for histopathological examination and biochemical estimation of brain content of acetylcholine esterase (AChE), neurotransmitters, oxidative stress markers, and interleukin-1β. CR produced prominent impairment in spatial and non-spatial learning memory, motor coordination, and muscular strength. Moreover, histopathological and biochemical alterations in brain contents of neurotransmitters, oxidative stress, and interleukin-1β were induced by CR. Conversely, RUT-CS/DA-PLUR, but not free RUT, successfully guarded against all the detrimental effects induced by CR. Based on the current findings, loading of RUT enhanced its bioavailability and therapeutic effectiveness by restoring the cognitive functions impaired by CR.

Neuroprotective Role of Polyphenols in Treatment of Neurological Disorders: A Review

: The most frequent illnesses characterized by the gradual malfunctioning of brain neurons are neurodegenerative disorders (NDs). Genetic mutations and a range of biological processes can produce NDs. Alzheimer's disease (AD), Parkinson's disease (PD), and Multiple Sclerosis (MS) are all related to oxidative stress (OS). Reduced brain activity has become a greater health threat with a growing elderly population. It causes some pathophysiological alterations and is an important risk factor for a range of neurodegenerative illnesses. An increase in reactive oxygen species (ROS) can cause neuronal cell death, and it is thus essential to control ROS levels to maintain normal neuronal activity. Synthetic medicines are often used to treat neurological disorders; however, harmful effects have been reported. Multiple bodies of research have shown the effectiveness of polyphenols in the treatment of various NDs due to their negligible side effects. This review article describes the neuroprotection effects of polyphenols such as resveratrol, epigallocatechin-3-gallate, curcumin, and quercetin, as well as the signaling pathways and immune response controls through polyphenols.

Piceatannol promotes hepatic and renal AMPK/SIRT1/PGC-1α mitochondrial pathway in rats exposed to reserpine or gamma-radiation

Human exposure to radio-therapeutic doses of gamma rays can produce late effects, which negatively affect cancer patients' quality of life, work prospects, and general health. This study was performed to explore the role of Piceatannol (PIC) in the process of "mitochondrial biogenesis" signaling pathway as possible management of disturbances induced in stressed animal model(s) either by gamma-irradiation (IR) or administration of reserpine (RES); as a mitochondrial complex-I inhibitor. PIC (10 mg/kg BW/day; orally) were given to rats for 7 days, after exposure to an acute dose of γ-radiation (6 Gy), or after a single reserpine injection (1 g/kg BW; sc). Compared to reserpine or γ-radiation, PIC has attenuated hepatic and renal mitochondrial oxidative stress denoted by the significant reduction in the content of lipid peroxides and NO with significant induction of SOD, CAT, GSH-PX, and GR activities. PIC has also significantly alleviated the increase of the inflammatory markers, TNF-α and IL-6 and apoptotic markers, cytochrome c, and caspase-3. The decrease of oxidative stress, inflammation, and apoptotic responses were linked to a significant amelioration in mitochondrial biogenesis demonstrated by the increased expression and proteins' tissue contents of SIRT1/p38-AMPK, PGC-1α signaling pathway. The results are substantiated by the significant amelioration in mitochondrial function verified by the higher levels of ATP content, and complex I activity, besides the improvement of hepatic and renal functions. Additionally, histopathological examinations of hepatic and renal tissues showed that PIC has modulated tissue architecture after reserpine or gamma-radiation-induced tissue damage. Piceatannol improves mitochondrial functions by regulating the oxidant/antioxidant disequilibrium, the inflammatory and apoptotic responses, suggesting its possible use as adjuvant therapy in radio-therapeutic protocols to attenuate hepatic and renal injuries.

Intravenous Administration of Coenzyme Q10 in Acute Period of Cerebral Ischemia Decreases Mortality by Reducing Brain Necrosis and Limiting Its Increase within 4 Days in Rat Stroke Model

Oxidative stress plays a key role in the pathogenesis of ischemic stroke. Coenzyme Q10 has a multi-targeting effect and may protect the brain against ischemic damage. The aim of our study was to evaluate the neuroprotective potential of ubiquinol by its intravenous administration. The study was performed on rats; a stroke was modeled by occlusion of the middle cerebral artery. On days 1 and 4 after ischemia, the neurological deficit and volume of the brain lesion were determined by MRI and TTC staining. Intravenous administration of coenzyme Q10 led to a decrease in rat mortality rate, improvement in neurological status, and decrease in the brain necrosis area in acute and delayed period after cerebral ischemia. A single intravenous administration of ubiquinol led to a limitation of the size of the brain damage for at least four days after ischemia. Thus, intravenous administration of coenzyme Q10 has a persistent neuroprotective potential. This finding suggests a possible therapeutic role of ubiquinol in acute ischemic conditions.

Protective effect of hypothermia and vitamin E on spermatogenic function after reduction of testicular torsion in rats

This study was designed to investigate the protective effect of hypothermia and vitamin E on spermatogenic function after reduction of testicular torsion in rats. Ninety-six pure inbred male SD rats were divided into group A, B, C and D according to the principle of body weight and birth similarity, with 24 rats in each group. Four groups of rats were respectively twisted on the left testis to establish unilateral testicular torsion rats. Rats in groups A, B, C, D were respectively given normal saline, hypothermia therapy, vitamin E therapy, and hypothermia and vitamin E therapy. The superoxide dismutase (SOD) activity and malondialdehyde (MDA) content of the four groups were detected, and the correlation levels of inflammatory factors IL-1β, hs-CRP and related sex hormones luteinizing hormone (LH), follicle-stimulating hormone (FSH), total testosterone (T) were detected by ELISA. Apoptosis of spermatogenic cells of testis in the four groups was detected by flow cytometry. SOD activity and MDA content in groups B, C and D were significantly higher than those in group A, MDA content was significantly lower than that in group A (P<0.05), SOD activity in group D was higher than that in groups B and C, while MDA content was lower than that in groups B and C (P<0.05). The levels of IL-1β and hs-CRP in group A were much higher than those in groups B, C and D (P<0.05). LH and FSH levels in group A were significantly higher than those in groups B, C and D (P<0.05), and in group D were significantly lower than those in groups B and C (P<0.05). Apoptosis rate of spermatogenic cells in group A was significantly higher than that in groups B, C and D (P<0.05). Hypothermia combined with vitamin E can reverse testicular injury in rats and reduce the apoptosis rate of spermatogenic cells.

Neuroprotective effect of Wogonin on Rat's brain exposed to gamma irradiation

Wogonin (5,7-dihydroxy-8-methoxy flavone), an active component isolated from the root of Scutellaria baicalensis Georgi. Neurotoxic effects of γ irradiation have been established in humans and animals. The current study was designed to evaluate whether wogonin could restrain γ irradiation-induced neurotoxicity in rats and to explore the underlying mechanisms. Rats were divided into five groups, 10 rats each. Group 1 was orally administered distilled water and served as control. Group 2 received an oral daily dose of wogonin (30 mg/kg). Rats in group 3 were exposed to a whole-body single dose of γ-irradiation. Animals in group 4 received an oral daily dose of wogonin (30 mg/kg) for 15 days then exposed to a whole-body single dose of γ-irradiation. In group 5, rats were exposed to a whole-body single dose of γ-irradiation then were orally administered a daily dose of wogonin (30 mg/kg) for 15 days. There were significant increases in malondialdehyde (MDA), tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and Interleukin 6 (IL-6) levels and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) mRNA and protein expression. Whereas significant decreases in reduced glutathione (GSH), superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX) level as well as nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) mRNA and protein expression in the irradiated group when compared with the relevant control. The cerebral cortex of irradiated rats showed vacuolization and nuclear pyknosis in the neuronal cells and focal gliosis. Wogonin administration pre- or post-irradiation significantly ameliorated all these previous effects. Wogonin had antioxidant and anti-inflammatory effects and ameliorated the histopathological changes in the brain.

SlMYB12 Regulates Flavonol Synthesis in Three Different Cherry Tomato Varieties

Cherry tomato (Lycopersicon esculentum M.) is considered a healthy fruit worldwide due to its wide range of nutrients. Flavonol, one of the major nutrients in cherry tomato, has antioxidant and cell-modulating properties. In this study, we showed a correlation between the expression of SlMYB12 and flavonol content (R² = 0.922). To characterize the function of SlMYB12, SlMYB12-overexpressing transgenic tomato plants were generated in three different cherry tomato varieties. Significant increases in flavonol content and flavonol biosynthetic gene expression were identified in SlMYB12-overexpressing plants. Therefore, we suggest that SlMYB12 plays a positive role in the flavonol biosynthesis pathway in cherry tomatoes, which further indicates a potential role as a marker in analyzing flavonol content in different cherry tomato varieties.

Neuroprotective mechanisms of rutin for spinal cord injury through anti-oxidation and anti-inflammation and inhibition of p38 mitogen activated protein kinase pathway

Rutin has anti-inflammatory, antioxidant, anti-viral, anti-tumor and immune regulatory effects. However, the neuroprotective effects of rutin in spinal cord injury are unknown. The p38 mitogen activated protein kinase (p38 MAPK) pathway is the most important member of the MAPK family that controls inflammation. We assumed that the mechanism of rutin in the repair of spinal cord injury is associated with the inhibition of p38 MAPK pathway. Allen's method was used to establish a rat model of spinal cord injury. The rat model was intraperitoneally injected with rutin (30 mg/kg) for 3 days. After treatment with rutin, Basso, Beattie and Bresnahan locomotor function scores increased. Water content, tumor necrosis factor alpha, interleukin 1 beta, and interleukin 6 levels, p38 MAPK protein expression and caspase-3 and -9 activities in T_8–9 spinal cord decreased. Oxidative stress related markers superoxide dismutase and glutathione peroxidase levels increased in peripheral blood. Rutin exerts neuroprotective effect through anti-oxidation, anti-inflammation, anti-apoptosis and inhibition of p38 MAPK pathway.

Coenzyme Q10 Regulates Antioxidative Stress and Autophagy in Acute Myocardial Ischemia-Reperfusion Injury

Background

Oxidative stress and autophagy both play key roles in continuous cardiomyocyte death and cardiac dysfunction after reperfusion therapy for acute myocardial ischemia-reperfusion injury. Coenzyme Q10 (CQ10), which is a fat-soluble quinone antioxidant, is involved in the pathophysiological processes of neurodegenerative diseases, cancer, diabetes, heart failure, and other diseases. Our objective was to determine if, and by what mechanism, CQ10 can ameliorate acute myocardial ischemia-reperfusion injury and improve heart function.

Methods and Results

Fat-soluble CQ10 in soybean oil solvent was preconditioned in rats with acute myocardial ischemia-reperfusion injury by intraperitoneal injection. Oxidant and antioxidant levels were compared between the preconditioned and control groups. Autophagy was measured by Western blotting analysis of autophagy proteins. Proapoptotic proteins and immunofluorescence were used to assess cell apoptosis. Infarct size was determined by triphenyl tetrazolium chloride (TTC) staining and Evans blue staining and visualized myocardial pathology by tissue staining. Finally, we assessed cardiac function by electrocardiography (ECG) and hemodynamics.

Conclusions

This study reveals that CQ10 preconditioning regulates antioxidant levels and the oxidant balance, enhances autophagy, reduces myocardial apoptosis and death, and improves cardiac function in rats with acute ischemia-reperfusion injury. These results imply that CQ10 protects against acute myocardial ischemia-reperfusion injury via the antioxidative stress and autophagy pathways.

CoQ10 Augments Rosuvastatin Neuroprotective Effect in a Model of Global Ischemia via Inhibition of NF-κB/JNK3/Bax and Activation of Akt/FOXO3A/Bim Cues

Statins were reported to lower the Coenzyme Q10 (CoQ10) content upon their inhibition of HMG-CoA reductase enzyme and both are known to possess neuroprotective potentials; therefore, the aim is to assess the possible use of CoQ10 as an adds-on therapy to rosuvastatin to improve its effect using global I/R model. Rats were allocated into sham, I/R, rosuvastatin (10 mg/kg), CoQ10 (10 mg/kg) and their combination. Drugs were administered orally for 7 days before I/R. Pretreatment with rosuvastatin and/or CoQ10 inhibited the hippocampal content of malondialdehyde, nitric oxide, and boosted glutathione and superoxide dismutase. They also opposed the upregulation of gp91^phox, and p47^phox subunits of NADPH oxidase. Meanwhile, both agents reduced content/expression of TNF-α, iNOS, NF-κBp65, ICAM-1, and MPO. Besides, all regimens abated cytochrome c, caspase-3 and Bax, but increased Bcl-2 in favor of cell survival. On the molecular level, they increased p-Akt and its downstream target p-FOXO3A, with the inhibition of the nuclear content of FOXO3A to downregulate the expression of Bim, a pro-apoptotic gene. Additionally, both treatments downregulate the JNK3/c-Jun signaling pathway. The effect of the combination regimen overrides that of either treatment alone. These effects were reflected on the alleviation of the hippocampal damage in CA1 region inflicted by I/R. Together, these findings accentuate the neuroprotective potentials of both treatments against global I/R by virtue of their rigorous multi-pronged actions, including suppression of hippocampal oxidative stress, inflammation, and apoptosis with the involvement of the Akt/FOXO3A/Bim and JNK3/c-Jun/Bax signaling pathways. The study also nominates CoQ10 as an adds-on therapy with statins.

Rutin-Enriched Extract from Coriandrum sativum L. Ameliorates Ionizing Radiation-Induced Hematopoietic Injury

Hematopoietic injury is a major cause of mortality in radiation accidents and a primary side effect in patients undergoing radiotherapy. Ionizing radiation (IR)-induced myelosuppression is largely attributed to the injury of hematopoietic stem and progenitor cells (HSPCs). Coriander is a culinary herb with multiple pharmacological effects and has been widely used in traditional medicine. In this study, flavonoids were identified as the main component of coriander extract with rutin being the leading compound (rutin-enriched coriander extract; RE-CE). We evaluated the radioprotective effect of RE-CE against IR-induced HSPCs injury. Results showed that RE-CE treatment markedly improved survival, ameliorated organ injuries and myelosuppression, elevated HSPCs frequency, and promoted differentiation and proliferation of HSPCs in irradiated mice. The protective role of RE-CE in hematopoietic injury is probably attributed to its anti-apoptotic and anti-DNA damage effect in irradiated HSPCs. Moreover, these changes were associated with reduced reactive oxygen species (ROS) and enhanced antioxidant enzymatic activities in irradiated HSPCs. Collectively, these findings demonstrate that RE-CE is able to ameliorate IR-induced hematopoietic injury partly by reducing IR-induced oxidative stress.

Effect of rutin against a mitochondrial toxin, 3-nitropropionicacid induced biochemical, behavioral and histological alterations-a pilot study on Huntington's disease model in rats

Dietary compounds like flavonoids may offer protection against neurodegeneration. Huntington's disease (HD) is a neurodegenerative disorder characterized by symptoms like chorea and dementia. 3-Nitropropionic acid (3-NP), a Succinate dehydrogenase (SDH) inhibitor produces behavioral, biochemical and histological changes in the striatum, mimics HD in animals and humans. The present study was designed to examine the protective activity of Rutin (RT), a primary flavonoid from citrus fruits, green tea on 3-NP induced experimental model of HD in rats. Rats were pretreated with Rutin, a potent antioxidant (25 and 50 mg/kg b.w.) orally prior to the intraperitoneally (i.p.) administration of 3-NP (10 mg/kg b.w.) for 14 days. Behavioral assessments were carried out on 5th, 10th and 15th day after 3-NP treatment. Body weight, biochemical and histological studies were analyzed on 15th day. Systemic administration of 3-NP significantly reduced the body weight, locomotor activities (Rota rod, Open field test), memory (Morris water maze) and antioxidants such as Glutathione (GSH) levels, activities of Superoxide dismutase (SOD), Catalase (CAT), Glutathione peroxidase (GPx), Glutathione-S-transferase (GST), Glutathione reductase (GR). 3-NP also produces striatal damage by increased the levels of lipid peroxides, nitrite, Glial Fibrillary Acidic Protein (GFAP) and activity of Acetylcholine esterase (AchE). Thus, Rutin treatment of 25 and 50 mg/kg b.w. has significantly restored all the biochemical, behavioral and histological alterations caused by the 3-NP through its antioxidant activity. The findings of our study indicates that Rutin may have an important role in protecting the striatum from oxidative/nitrosative insults caused by 3-NP. These results suggest that RT might be a drug of choice to treat HD.

Protective effect of rutin on cognitive impairment caused by phenytoin

Objective:

To study the effect of the co-administration of phenytoin (PHT) and rutin in comparison with PHT and piracetam (PIM) on seizure control, cognitive, and motor functions in mice.

Materials and Methods:

Increasing current electroshock seizure (ICES) test was used to evaluate the effect of the co-administration of PHT and PIM on convulsions. Cognitive functions in mice were assessed by a spontaneous alternation in behavior on a plus maze while motor functions were screened using rolling roller apparatus and by counting the number of arms entries on a plus maze. Brain acetyl-cholinesterase (AChE) activity was also estimated.

Statistical Analysis:

The expression of data was done as mean ± standard error of the mean. The normally distributed data were subjected to one-way ANOVA followed by Dunnett's test. P < 0.05 was considered significant.

Results:

The study showed that rutin when co-administered with PHT, significantly reversed PHT-induced reduction in spontaneous alternation without altering the efficacy of PHT against ICES, in both acute and chronic studies. Further, it also reversed PHT-induced increase in AChE activity.

Conclusion:

Rutin alleviated the PHT-induced cognitive impairment without compromising its antiepileptic efficacy.

Protective effects of vitamin E against liver damage caused by renal ischemia reperfusion

Recent studies have reported that remote organs are affected by renal ischemia reperfusion (IR). The present study investigates the role of vitamin E on the liver damage after renal IR. First, male mice were subjected to three groups (n = 9): 1) sham-operated, (2) renal IR (45 min ischemia), (3) renal IR + Vitamin E (150 mg/kg trough feeding tube for 28 d). After 24 h of reperfusion, animal were anesthetized for sample collections. Liver tissues malondialdehyde (MDA) increased and total glutathione (GSH) concentration decreased in the IR group compared to the sham group. Vitamin E consumption diminished the IR-induced increase in plasma AST and ALT. In addition, Vitamin E inhibited the IR-induced decrease in GSH activity and diminished IR-induced increase in MDA concentration. These findings showed that vitamin E consumption partly inhibited the IR-induced liver damage.

Rutin decreases lipopolysaccharide-induced acute lung injury via inhibition of oxidative stress and the MAPK-NF-κB pathway

Acute lung injury (ALI) is a serious disease with unacceptably high mortality and morbidity rates. Up to now, no effective therapeutic strategy for ALI has been established. Rutin, quercetin-3-rhamnosyl glucoside, expresses a wide range of biological activities and pharmacological effects, such as anti-inflammatory, antihypertensive, anticarcinogenic, vasoprotective, and cardioprotective activities. Pretreatment with rutin inhibited not only histopathological changes in lung tissues but also infiltration of polymorphonuclear granulocytes into bronchoalveolar lavage fluid in lipopolysaccharide (LPS)-induced ALI. In addition, LPS-induced inflammatory responses, including increased secretion of proinflammatory cytokines and lipid peroxidation, were inhibited by rutin in a concentration-dependent manner. Furthermore, rutin suppressed phosphorylation of NF-κB and MAPK and degradation of IκB, an NF-κB inhibitor. Decreased activities of antioxidative enzymes such as superoxide dismutase, catalase, glutathione peroxidase, and heme oxygenase-1 caused by LPS were reversed by rutin. At the same time, we found that ALI amelioration by chelation of extracellular metal ions with rutin is more efficacious than with deferoxamine. These results indicate that the protective mechanism of rutin is through inhibition of MAPK-NF-κB activation and upregulation of antioxidative enzymes.

Polyphenols: multipotent therapeutic agents in neurodegenerative diseases

Aging leads to numerous transitions in brain physiology including synaptic dysfunction and disturbances in cognition and memory. With a few clinically relevant drugs, a substantial portion of aging population at risk for age-related neurodegenerative disorders require nutritional intervention. Dietary intake of polyphenols is known to attenuate oxidative stress and reduce the risk for related neurodegenerative diseases such as Alzheimer's disease (AD), stroke, multiple sclerosis (MS), Parkinson's disease (PD), and Huntington's disease (HD). Polyphenols exhibit strong potential to address the etiology of neurological disorders as they attenuate their complex physiology by modulating several therapeutic targets at once. Firstly, we review the advances in the therapeutic role of polyphenols in cell and animal models of AD, PD, MS, and HD and activation of drug targets for controlling pathological manifestations. Secondly, we present principle pathways in which polyphenol intake translates into therapeutic outcomes. In particular, signaling pathways like PPAR, Nrf2, STAT, HIF, and MAPK along with modulation of immune response by polyphenols are discussed. Although current polyphenol researches have limited impact on clinical practice, they have strong evidence and testable hypothesis to contribute clinical advances and drug discovery towards age-related neurological disorders.

Therapeutic potential of treatment with the flavonoid rutin after cortical focal ischemia in rats

Flavonoids have known anti-inflammatory and antioxidative actions, and they have been described as neuroprotective and able to reduce damage in CNS diseases. We evaluated the action of the flavonoid rutin in an animal model of focal cortical ischemia induced by unilateral thermocoagulation of superficial blood vessels of motor (M1) and somatosensory (S1) primary cortices. Ischemic rats were submitted to daily injections (i.p.) for five days, starting immediately after induction of ischemia. We tested two doses: 50mg/kg or 100mg/kg of body weight. Sensorimotor tests were used to evaluate functional recovery. Bioavailability in plasma was done by chromatographic analysis. The effect of treatment in lesion volume and neurodegeneration was evaluated 48 h and 72 h after ischemia, respectively. We observed significant sensorimotor recovery induced by rutin, and the dose of 50mg/kg had more pronounced effect. Thus, this dose was used in further analyses. Plasma availability of rutin was detected from 2h to at least 8h after ischemia. The treatment did not result in reduction of lesion volume but reduced the number of degenerated neurons at the periphery of the lesion. The results suggest rutin as an efficient drug to treat brain ischemia since it was able to promote significant recovery of sensorimotor loss, which was correlated to the reduction of neurodegeneration in the periphery of cortical injury. Increasing studies with rutin and other flavonoids might give support for further clinical trials with these drugs.

Coenzyme Q10 protects neural stem cells against hypoxia by enhancing survival signals

Recanalization and secondary prevention are the main therapeutic strategies for acute ischemic stroke. Neuroprotective therapies have also been investigated despite unsuccessful clinical results. Coenzyme Q10 (CoQ10), which is an essential cofactor for electron transport in mitochondria, is known to have an antioxidant effect. We investigated the protective effects of CoQ10 against hypoxia in neural stem cells (NSCs). We measured cell viability and levels of intracellular signaling proteins after treatment with several concentrations of CoQ10 under hypoxia-reperfusion. CoQ10 protected NSCs against hypoxia-reperfusion in a concentration-dependent manner by reducing growth inhibition and inhibiting free radical formation. It increased the expression of a number of survival-related proteins such as phosphorylated Akt (pAkt), phosphorylated glycogen synthase kinase 3-β (pGSK3-β), and B-cell lymphoma 2 (Bcl-2) in NSCs injured by hypoxia-reperfusion and reduced the expression of death-related proteins such as cleaved caspase-3. We conclude that CoQ10 has effects against hypoxia-reperfusion induced damage to NSCs by enhancing survival signals and decreasing death signals.

The neuroprotective effect of vitamin E on chronic sleep deprivation-induced memory impairment: the role of oxidative stress

Sleep deprivation induces oxidative stress and impairs learning and memory processes. Vitamin E, on the other hand, is a strong antioxidant that has neuroprotective effect on the brain. In this study, we examined the potential protective effect of chronic administration of vitamin E on chronic sleep deprivation-induced cognitive impairment. In addition, possible molecular targets for vitamin E effects on chronic sleep deprivation-induced cognitive impairment were determined. Sleep deprivation was induced in rats using modified multiple platform model. Vitamin E (100mg/kg) was administered to animals by oral gavage. Behavioral study was conducted to test the spatial learning and memory using the radial arm water maze (RAWM). In addition, the hippocampus was dissected out and antioxidant markers including glutathione (GSH), oxidized glutathione (GSSG) and GSH/GSSG, glutathione peroxidase (GPx), catalase, and superoxide dismutase (SOD) were assessed. The results of this project revealed that chronic sleep deprivation impaired both (short- and long-term) memories (P<0.05), while vitamin E treatment prevented such effect. Additionally, vitamin E normalized chronic sleep deprivation-induced reduction in the hippocampus GSH/GSSG ratio, and activity of catalase, SOD, and GPx. In conclusion, sleep deprivation induces memory impairment, and treatment with vitamin E prevented this impairment probably through its antioxidant action in the hippocampus.