Effect of glucocorticoids on 3-nitropropionic acid-induced oxidative stress in synaptosomes

Effect of Capsaicin on 3-NP-Induced Neurotoxicity: A Pre-Clinical Study

The study objectives are to investigate the ability of capsaicin to revert the toxic effects in glutamate and lipopolysaccharide (LPS)-induced neurotoxicity in Neuro2a (N2a) cells as well as thwarting cognitive impairments, mitochondrial deficits, and oxidative insults induced by 3-nitropropanoic acid (3-NP) in a rodent model of Huntington's disease. In-vitro study with N2a cells was performed through MTT and LDH assay and their biochemical examinations were also performed. 3-NP-administered mice (n = 6) were treated with capsaicin (5, 10, and 20 mg/kg) through the per-oral (p.o.) route for 7 consecutive days. Physiological and behavioral studies were performed in drug-treated mice. After behavioral studies, biochemical parameters were performed for cytokines levels, various oxidative stress parameters, and mitochondrial enzyme complex activities with mitochondrial permeability. N2a cells treated with capsaicin demonstrated neuroprotective effects and reduced neurotoxicity. Based on experimental observation, in an in-vitro study, the effective dose of CAP was 50 µM. Moreover, a 100 µM dose of capsaicin had toxic effects on neuronal cells (N2a cells). On the other hand, the effective dose of 3-NP was 20 mg/kg, (p.o.) in animals (in-vivo). All tested doses of capsaicin upturned the cognitive impairment and motor in-coordination effects induced by 3-NP. 3-NP-injected mice demonstrated substantially increased pro-inflammatory cytokine concentrations, defective mitochondrial complex activity, and augmented oxidative insult. However, capsaicin at different doses reduced oxidative damage and cytokines levels and improved mitochondrial complex activity along with mitochondrial permeability. Furthermore, capsaicin (10 and 20 mg/kg) improved the TNF-α concentration. These findings suggested because of the anti-inflammatory and antioxidant effect, capsaicin can be considered a novel treatment for the management of neurodegenerative disorders by reverting the antioxidant enzyme activity, pro-inflammatory cytokines concentration, and mitochondrial functions.

6-shogaol against 3-Nitropropionic acid-induced Huntington's disease in rodents: Based on molecular docking/targeting pro-inflammatory cytokines/NF-κB-BDNF-Nrf2 pathway

BACKGROUND

Huntington's disease (HD) is an extremely harmful autosomal inherited neurodegenerative disease. Motor dysfunction, mental disorder, and cognitive deficits are the characteristic features of this disease. The current study examined whether 6-shogaol has a protective effect against 3-Nitropropionic Acid (3-NPA)-induced HD in rats.

METHODS

A total of thirty male Wistar rats received 6-shogaol (10 and 20 mg/kg, per oral) an hour before injection of 3-NPA (10 mg/kg i.p.) for 15 days. Behavioral tests were performed, including narrow beam walk, rotarod test, and grip strength test. Biochemical tests promoting oxidative stress were evaluated [superoxide dismutase (SOD), reduced glutathione (GSH), catalase (CAT) and malondialdehyde (MDA)], including changes to neurotransmitters serotonin (5-HT), dopamine (DA), norepinephrine (NE), homovanillic acid (HVA), (3,4-dihydroxyphenylacetic acid (DOPAC), γ-aminobutyric acid (GABA), and 5-hydroxy indole acetic acid (5-HIAA), nuclear factor kappa-B (NF-κB), tumor necrosis factor-α (TNF-α), interleukins-1β (IL-1β), IL-6, brain-derived neurotrophic factor (BDNF), and nuclear factor erythroid 2-related factor 2 (Nrf2). The 6-shogaol was docked to the active site of TNF-α (2AZ5), NF-κB (1SVC), BDNF) [1B8M], and Nrf2 [5FZN] proteins using AutoDock tools.

RESULTS

The 6-shogaol group significantly improved behavioral activity over the 3-NPA-injected control rats. Moreover, 3-NPA-induced significantly altered neurotransmitters, biochemical and neuroinflammatory indices, which could efficiently be reversed by 6-shogaol. The 6-shogaol showed favorable negative binding energies at -9.271 (BDNF) kcal/mol.

CONCLUSIONS

The present investigation demonstrated the neuroprotective effects of 6-shogaol in an experimental animal paradigm against 3-NPA-induced HD in rats. The suggested mechanism is supported by immunohistochemical analysis and western blots, although more research is necessary for definite confirmation.

Clinical outcomes of chemotherapy in cancer patients with different ethnicities

BACKGROUND

Choosing the most effective chemotherapeutic agent with safest side effect profile is a common challenge in cancer treatment. Although there are standardized chemotherapy protocols in place, protocol changes made after extensive clinical trials demonstrate significant improvement in the efficacy and tolerability of certain drugs. The pharmacokinetics, pharmacodynamics, and tolerance of anti-cancer medications are all highly individualized. A driving force behind these differences lies within a person's genetic makeup.

RECENT FINDINGS

Pharmacogenomics, the study of how an individual's genes impact the processing and action of a drug, can optimize drug responsiveness and reduce toxicities by creating a customized medication regimen. However, these differences are rarely considered in the initial determination of standardized chemotherapeutic protocols and treatment algorithms. Because pharmacoethnicity is influenced by both genetic and nongenetic variables, clinical data highlighting disparities in the frequency of polymorphisms between different ethnicities is steadily growing.  Recent data suggests that ethnic variations in the expression of allelic variants may result in different pharmacokinetic properties of the anti-cancer medication. In this article, the clinical outcomes of various chemotherapy classes in patients of different ethnicities were reviewed.

CONCLUSION

Genetic and nongenetic variables contribute to the interindividual variability in response to chemotherapeutic drugs. Considering pharmacoethnicity in the initial determination of standard chemotherapeutic protocols and treatment algorithms can lead to better clinical outcomes of patients of different ethnicities.

Oxidative stress and COVID-19-associated neuronal dysfunction: mechanisms and therapeutic implications

Severe acute respiratory syndrome (SARS)-CoV-2 virus causes novel coronavirus disease 2019 (COVID-19), and there is a possible role for oxidative stress in the pathophysiology of neurological diseases associated with COVID-19. Excessive oxidative stress could be responsible for the thrombosis and other neuronal dysfunctions observed in COVID-19. This review discusses the role of oxidative stress associated with SARS-CoV-2 and the mechanisms involved. Furthermore, the various therapeutics implicated in treating COVID-19 and the oxidative stress that contributes to the etiology and pathogenesis of COVID-19-induced neuronal dysfunction are discussed. Further mechanistic and clinical research to combat COVID-19 is warranted to understand the exact mechanisms, and its true clinical effects need to be investigated to minimize neurological complications from COVID-19.

Protective Effect of Fustin against Huntington's Disease in 3-Nitropropionic Treated Rats via Downregulation of Oxidative Stress and Alteration in Neurotransmitters and Brain-Derived Neurotrophic Factor Activity

Researchers have revealed that Rhus verniciflua heartwood, which contains fustin as an important component, possesses antioxidant-mediated, anti-mutagenic, and anti-rheumatoid arthritis characteristics. Additionally, out of the numerous plant-derived secondary metabolites, there are various research papers concentrating on flavonoids for potential advantages in neurological illnesses. The current study aims to assess the neuroprotective potential of fustin in rodents over 3-nitropropionic acid (3-NPA)-induced Huntington's disease (HD)-like consequences. The efficacy of fustin 50 and 100 mg/kg was studied with multiple-dose administrations of 3-NPA, which experimentally induced HD-like symptoms in rats for 22 days. At the end of the study, several behavioral tests were performed including a beam walk, rotarod, and grip strength tests. Similarly, some biochemical parameters were assessed to support oxidative stress (reduced glutathione-GSH, superoxide dismutase-SOD, catalase-CAT, and malondialdehyde-MDA), alteration in neurotransmitters (gamma-aminobutyric acid-GABA-and glutamate), alteration in brain-derived neurotrophic factor activity, and nitrite levels. Additionally, pro-inflammatory parameters were carried out to evaluate the neuroinflammatory responses associated with streptozotocin such as TNF-α, IL-1β, and COX in the perfused brain. The fustin-treated group exhibited a significant restoration of memory function via modulation in behavioral activities. Moreover, 3-NPA altered biochemical, neurotransmitters, brain protein levels, and neuroinflammatory measures, which fustin efficiently restored. This is the first report demonstrating the efficacy of novel phytoconstituent fustin as a potential future candidate for the treatment of HD via offering neuroprotection by subsiding the oxidative and enzymatic activity in the 3-NPA experimental animal paradigm.

Beta-Boswellic Acid Reverses 3-Nitropropionic Acid-Induced Molecular, Mitochondrial, and Histopathological Defects in Experimental Rat Model of Huntington's Disease

Huntington's disease (HD) is distinguished by a triple repeat of CAG in exon 1, an increase in poly Q in the Htt gene, and a loss of GABAergic medium spiny neurons (MSN) in the striatum and white matter of the cortex. Mitochondrial ETC-complex dysfunctions are involved in the pathogenesis of HD, including neuronal energy loss, synaptic neurotrophic decline, neuronal inflammation, apoptosis, and grey and white matter destruction. A previous study has demonstrated that beta Boswellic acid (β-BA), a naturally occurring phytochemical, has several neuroprotective properties that can reduce pathogenic factors associated with various neurological disorders. The current investigation aimed to investigate the neuroprotective potential of β-BA at oral doses of 5, 10, and 15 mg/kg alone, as well as in conjunction with the potent antioxidant vitamin E (8 mg/kg, orally) in 3-NP-induced experimental HD rats. Adult Wistar rats were separated into seven groups, and 3-NP, at a dose of 10 mg/kg, was orally administered to each group of adult Wistar rats beginning on day 1 and continuing through day 14. The neurotoxin 3-NP induces neurodegenerative, g, neurochemical, and pathological alterations in experimental animals. Continuous injection of 3-NP, according to our results, aggravated HD symptoms by suppressing ETC-complex-II, succinate dehydrogenase activity, and neurochemical alterations. β-BA, when taken with vitamin E, improved behavioural dysfunctions such as neuromuscular and motor impairments, as well as memory and cognitive abnormalities. Pharmacological treatments with β-BA improved and restored ETC complexes enzymes I, II, and V levels in brain homogenates. β-BA treatment also restored neurotransmitter levels in the brain while lowering inflammatory cytokines and oxidative stress biomarkers. β-BA's neuroprotective potential in reducing neuronal death was supported by histopathological findings in the striatum and cortex. As a result, the findings of this research contributed to a better understanding of the potential role of natural phytochemicals β-BA in preventing neurological illnesses such as HD.

Transcranial Magnetic Stimulation Improves Muscle Involvement in Experimental Autoimmune Encephalomyelitis

Skeletal muscle is affected in experimental autoimmune encephalomyelitis (EAE), which is a model of multiple sclerosis that produces changes including muscle atrophy; histological features of neurogenic involvement, and increased oxidative stress. In this study, we aimed to evaluate the therapeutic effects of transcranial magnetic stimulation (TMS) on the involvement of rat skeletal muscle and to compare them with those produced by natalizumab (NTZ). EAE was induced by injecting myelin oligodendrocyte glycoprotein (MOG) into Dark Agouti rats. Both treatments, NTZ and TMS, were implemented from day 15 to day 35. Clinical severity was studied, and after sacrifice, the soleus and extensor digitorum longus muscles were extracted for subsequent histological and biochemical analysis. The treatment with TMS and NTZ had a beneficial effect on muscle involvement in the EAE model. There was a clinical improvement in functional motor deficits, atrophy was attenuated, neurogenic muscle lesions were reduced, and the level of oxidative stress biomarkers was lower in both treatment groups. Compared to NTZ, the best response was obtained with TMS for all the parameters analyzed. The myoprotective effect of TMS was higher than that of NTZ. Thus, the use of TMS may be an effective strategy to reduce muscle involvement in multiple sclerosis.

Transplantation of human dental pulp stem cells compensates for striatal atrophy and modulates neuro-inflammation in 3-nitropropionic acid rat model of Huntington's disease

Stem cell-based therapy has recently offered a promising alternative for the remedy of neurodegenerative disorders like Huntington's disease (HD). Herein, we investigated the potential ameliorative effects of implantation of dental pulp stem cells (DPSCs) in 3-nitropropionic acid (3-NP) rat models of HD. In this regard, human DPSCs were isolated, culture-expanded and implanted in rats lesioned with 3-NP. Post-transplantation examinations revealed that DPSCs were able to survive and augment motor skills and muscle activity. Histological analysis showed DPSCs treatment hampered the shrinkage of the striatum along with the inhibition of gliosis and microgliosis in the striatum of 3-NP rat models. We also detected the downregulation of Caspase-3 and pro-inflammatory cytokines such as TNF and IL-1β upon DPSCs grafting. Overall, these findings imply that the grafting of DPSCs could repair motor-skill impairment and induce neurogenesis, probably through the secretion of neurotrophic factors and the modulation of neuroinflammatory response in HD animal models.

Expression of PUMA in Follicular Granulosa Cells Regulated by FoxO1 Activation During Oxidative Stress

Many studies have demonstrated that oxidative stress-induced apoptosis is a main cause of follicular atresia. Reactive oxygen species (ROS)-induced granulosa cell (GC) apoptosis is regulated by a variety of signaling pathways involving numerous genes and transcription factors. In this study, we found expression of the p53-upregulated modulator of apoptosis (PUMA), a BH3-only Bcl-2 subfamily protein, in ovarian GCs during oxidative stress. By overexpression and knockdown of Forkhead box O1 (FoxO1), we found that FoxO1 regulates PUMA at the protein level. Moreover, as c-Jun N-terminal kinase (JNK) has been shown to activate FoxO1 by promoting its nuclear import, we used a JNK inhibitor to reduce FoxO1 activation and detected decreased PUMA messenger RNA expression and protein levels during oxidative stress. In addition, in vivo oxidative stress-induced upregulation of PUMA was found following injection of 3 nitropropionic acid in mice. In conclusion, oxidative stress increases PUMA expression regulated by FoxO1 in follicular GCs.

A rat model of hemidystonia induced by 3-nitropropionic acid

OBJECTIVE

Secondary dystonia commonly presents as hemidystonia and is often refractory to current treatments. We aimed to establish an inducible rat model of hemidystonia utilizing 3-nitropropionic acid (3-NP) and to determine the pathophysiology of this model.

METHODS

Two different doses of 3-NP were stereotactically administered into the ipsilateral caudate putamen (CPu) of Wistar rats. Behavioral changes and alterations in the neurotransmitter levels in the basal ganglia were analyzed. We also performed an electromyogram, 7.0-T magnetic resonance imaging and transmission electron microscopy examination to determine the pathophysiology of the model.

RESULTS

In the CPu region, 3-NP produced mitochondrial cristae rupture, axonal degeneration, increased excitatory synaptic vesicles and necrosis. The extracellular concentrations of excitatory amino acids increased, whereas the inhibitory amino acids decreased in the CPu. Furthermore, an imbalance of neurotransmitters was found in other regions of the basal ganglia with the exception of the external globus pallidus. This study demonstrated that 3-NP administration results in CPu damage, and combined with a neurotransmitter imbalance in the basal ganglia, it produces specific neurobehavioral changes in rats. Right limb (contralateral side of CPu lesion) and trunk dystonic postures, shortened step length and ipsiversive dystonic posturing were observed in these rats. Furthermore, EMG recordings confirmed that co-contraction of the agonist and antagonist muscles could be seen for several seconds in right limbs.

CONCLUSIONS

Stereotactic injection of 3-NP into the ipsilateral CPu of rats established an inducible model for hemidystonia. This effect might result from an imbalance of neurotransmitter levels, which induce dysfunctional activity of the basal ganglia mainly via the cortico-striato-GPi direct pathway. Symptoms in this model were present for 1 week. Activation of the cortico-striato-GPe indirect pathway and rebalance of neurotransmitters may lead to recovery. This rat model may be a suitable tool used to understand and further investigate the pathophysiology of dystonia.

Involvement of the up-regulated FoxO1 expression in follicular granulosa cell apoptosis induced by oxidative stress

Follicular atresia is common in female mammalian ovaries, where most follicles undergo degeneration at any stage of growth and development. Oxidative stress gives rise to triggering granulosa cell apoptosis, which has been suggested as a major cause of follicular atresia. However, the underlying mechanism by which the oxidative stress induces follicular atresia remains unclear. FoxO transcription factors are known as critical mediators in the regulation of oxidative stress and apoptosis. In this study, the involvement of FoxO1 in oxidative stress-induced apoptosis of mouse follicular granulosa cells (MGCs) was investigated in vivo and in vitro. It was observed that increased apoptotic signals correlated with elevated expression of FoxO1 in MGCs when mice were treated with the oxidant. Correspondingly, the expressions of FoxO1 target genes, such as proapoptotic genes and antioxidative genes, were also up-regulated. In primary cultured MGCs, treatment with H(2)O(2) led to FoxO1 nuclear translocation. Further studies with overexpression and knockdown of FoxO1 demonstrated the critical role of FoxO1 in the induction of MGC apoptosis by oxidative stress. Finally, inactivation of FoxO1 by insulin treatment confirmed that FoxO1 induced by oxidative stress played a pivotal role in up-regulating the expression of downstream apoptosis-related genes in MGCs. Our results suggest that up-regulation of FoxO1 by oxidative stress leads to apoptosis of granulosa cells, which eventually results in follicular atresia in mice.

Pretreatment with Bacopa monnieri extract offsets 3-nitropropionic acid induced mitochondrial oxidative stress and dysfunctions in the striatum of prepubertal mouse brain

The present investigation was designed to determine the efficacy of Bacopa monnieri (Brahmi; BM) to offset 3-nitropropionic acid (3-NPA) induced oxidative stress and mitochondrial dysfunction in dopaminergic (N27) cells and prepubertal mouse brain. Pretreatment of N27 cells with BM ethanolic extract (BME) significantly attenuated 3-NPA-induced cytotoxicity. Further, we determined the degree of oxidative stress induction, redox status, enzymic antioxidants, and protein oxidation in the striatal mitochondria of mice given BME prophylaxis followed by 3-NPA challenge. While 3-NPA-induced marked oxidative stress in the mitochondria of the striatum, BME prophylaxis markedly prevented 3-NPA-induced oxidative dysfunctions and depletion of reduced glutathione and thiol levels. The activities of antioxidant enzymes (superoxide dismutase, glutathione peroxidase, glutathione reductase, thioredoxin reductase), Na(+),K(+)-ATPase, and citric acid cycle enzymes in the striatum discernible among 3-NPA mice were significantly restored with BME prophylaxis. Interestingly, BME offered protection against 3-NPA-induced mitochondrial dysfunctions as evidenced by the restoration of the activities of ETC enzymes (NADH:ubiquinone oxidoreductase, NADH:cytochrome c reductase, succinate-ubiquinone oxidoreductase, and cytochrome c oxidase) and mitochondrial viability. We hypothesize that the neuroprotective effects of BME may be wholly or in part related to its propensity to scavenge free radicals, maintain redox status, and upregulate antioxidant machinery in striatal mitochondria.

Alterations in mRNA expression of steroid receptors and heat shock proteins in the liver of rare minnow (Grobiocypris rarus) exposed to atrazine and p,p'-DDE

The chaperon role of heat shock proteins (HSPs) throughout the life cycle of steroid receptors have been demonstrated in vitro. However, the actions of HSPs in steroid pathways in animals especially in fish were unclear. In this study, sexually mature rare minnows (Gobiocypris rarus) were exposed to typical endocrine disruptors (atrazine and p,p'-DDE). Hypertrophy of hepatocytes at the 333 microg/l atrazine treatment and atrophy of hepatocytes in all p,p'-DDE treatments were observed. The expression of liver hsp70 and hsp90 in atrazine treatments were significantly up-regulated. Moreover, remarkable increases in the expression of androgen receptor (ar) and estrogen receptor (er) were observed, while alterations of the glucoticorcoid receptor (gr) expression was not significant in atrazine exposed fish. The expression of ar, er, gr, hsp70 and hsp90 were significantly suppressed following p,p'-DDE exposure. These results demonstrate that the expression of hsp70 and hsp90 is altered along with changes of steroid receptors in vivo. Therefore, the results are consistent with the possibility that in fish heat shock proteins (HSPs) play chaperon roles for the steroid receptors in vivo, which also concurs with previous in vitro mammalian studies.

Cyclosporine A Attenuates 3-Nitropropionic Acid–Induced Huntington-Like Symptoms in Rats: Possible Nitric Oxide Mechanism

Cyclosporine A is a well-known immunosuppressant drug that is currently used for prevention of allograft rejection. The current study was conducted to explore the therapeutic potential of cyclosporine A against 3-nitropropionic acid (3-NP)–induced neurotoxicity, an animal model of Huntington disease (HD). Systemic administration of 3-NP (10 mg/kg) for 14 days significantly impaired body weight, motor activity, biochemical parameters (raised lipid peroxidation, nitrite concentration, depletion of superoxide dismutase [SOD] and catalase), and mitochondrial enzymes. Cyclosporine A (2.5, 5, and 10 mg/kg) treatment significantly attenuated behavioral, biochemical, and cellular alterations. Furthermore, l-arginine pretreatment with cyclosporine A (5 mg/kg) significantly reversed the protective effect of cyclosporine A. However, l-nitro-arginine methyl ester (l-NAME; 10 mg/kg) pretreatment potentiated the protective effect of cyclosporine A (5 mg/kg). Study highlights the therapeutic potential of cyclosporine A in the treatment of HP. Study suggests that nitric oxide (NO) modulation is involved in the neuroprotective effect of cyclosporine A against 3-NP neurotoxicity.

3-Nitropropionic acid as a tool to study the mechanisms involved in Huntington's disease: past, present and future

Huntington's disease (HD) is an inheritable autosomal-dominant disorder whose causal mechanisms remain unknown. Experimental models have begun to uncover these pathways, thus helping to understand the mechanisms implicated and allowing for the characterization of potential targets for new therapeutic strategies. 3-Nitropropionic acid is known to produce in animals behavioural, biochemical and morphologic changes similar to those occurring in HD. For this reason, this phenotypic model is gaining attention as a valuable tool to mimick this disorder and further developing new therapies. In this review, we will focus on the past and present research of this molecule, to finally bring a perspective on what will be next in this promising field of study.

Possible neuroprotective effect of Withania somnifera root extract against 3-nitropropionic acid-induced behavioral, biochemical, and mitochondrial dysfunction in an animal model of Huntington's disease

Huntington's disease (HD) is a neurodegenerative disorder that results from the destruction of neurons in the basal ganglia, and oxidative stress has been implicated in its pathogenesis. 3-Nitropropionic acid (3-NP), a potent neurotoxin, has been reported to induce oxidative/nitrosative stress and causes neurobehavioral and biochemical changes that mimic HD in humans. It also inhibits complex II of the mitochondrial electron transport chain, thereby causing cellular energy deficit. In the present work, we evaluated the effects of a well-known antioxidant on behavioral, biochemical, and mitochondrial dysfunction induced by 3-NP. The study was designed to investigate the effects of Withania somnifera root extract against 3-NP-induced gait abnormalities, oxidative stress, and mitochondrial dysfunction in striatum and cortex of rat brain. Intraperitoneal administration of 3-NP (10 mg/kg for 14 days) caused a loss in body weight and a decline in motor function (locomotor activity and impaired rotarod activity). Chronic treatment with W. somnifera root extracts (100 and 200 mg/kg) for a period of 2 weeks dose-dependently improved 3-NP-induced behavioral, biochemical, and enzymatic changes (P < .05). Biochemical analysis revealed that systemic 3-NP administration significantly increased lipid peroxidation and nitrite and lactate dehydrogenase enzyme levels, depleted antioxidant enzyme (superoxide dismutase and catalase) levels, and blocked ATP synthesis by inhibiting the mitochondrial complex activity in the different regions (striatum and cortex) of the brain. Chronic administration of W. somnifera root extract (100 and 200 mg/kg) dose-dependently restored biochemical alterations induced by chronic 3-NP treatment (P < .05). These findings suggest that neuroprotective actions of W. somnifera are mediated via its antioxidant activity. However, further studies are required to elucidate the molecular mechanisms involved in order to support the clinical use of the plant extract as a therapeutic agent for the treatment of HD.

Possible role of sertraline against 3-nitropropionic acid induced behavioral, oxidative stress and mitochondrial dysfunctions in rat brain

Oxidative stress and disrupted energy metabolism are major events leading to nerve cell death. Oxidative stress and related reactive oxygen species is one of the common cooperative sharing pathways involved in neurodegenerative disorders including Huntington's disease. The present study evaluated the possible role of sertraline on the 3-nitropropionic acid induced behavioral, biochemical, and mitochondrial alterations in discrete areas of rat brain. 3-Nitropropionic acid (10 mg/kg) administration for 14 days significantly induced Huntington's disease like symptoms in rats as indicated by change in locomotor activity, body weight, rotarod activity performance, oxidative damage (elevated levels of lipid peroxidation, nitrite concentration, depletion of antioxidant enzyme levels) and mitochondrial dysfunction (Complexes-I, II, II and IV) in striatum, cortex and hippocampal region of brain. Treatment with sertraline (5 and 10 mg/kg) significantly reversed behavioral, biochemical and mitochondrial enzyme dysfunctions in 3-nitropropionic acid treated group. Further, combination of yohimbine (2 mg/kg) (non selective serotonin with the higher dose of sertraline (10 mg/kg) did not influence the protective action of sertraline. The present study suggests the possible antioxidant role of sertraline against 3-nitropropionic acid induced alterations in animals.

Cyclooxygenase inhibition attenuates 3-nitropropionic acid-induced neurotoxicity in rats: possible antioxidant mechanisms

Systemic administration of 3-nitropropionic acid (3-NP), a complex II inhibitor of the electron transport chain, causes motor and cognitive deficits that are associated with excitotoxicity and excessive free radical generation. Recently, cyclooxygenase (COX) inhibitors have been implicated as a neuroprotectant in the treatment of various neurological disorders. The present study was designed to investigate the effects of COX inhibitors in 3-NP-induced cognitive impairment and oxidative stress in rats. Intraperitoneal administration of 3-NP (20 mg/kg for 4 days) showed motor abnormalities and cognitive impairment in rats. Chronic treatment with naproxen (10 and 20 mg/kg) and valdecoxib (5 and 10 mg/kg) once daily for a period of 8 days beginning 4 days prior to 3-NP administration significantly improved 3-NP-induced motor and cognitive impairment in rats. Biochemical analysis revealed that systemic 3-NP administration significantly increased lipid peroxidation and nitrite levels, depleted reduced glutathione levels and reduced succinate dehydrogenase (SDH) activity in the brains of rats, whereas administration of naproxen, a nonselective COX inhibitor (10 and 20 mg/kg p.o.) and valdecoxib, a selective COX-2 inhibitor (5 and 10 mg/kg p.o.) significantly attenuated 3-NP-induced oxidative stress. Cyclooxygenase inhibitors also significantly restored the decreased SDH activity. The results of the present study clearly indicate that naproxen and valdecoxib showed protection against 3-NP-induced motor and cognitive impairment by decreasing oxidative stress.

Effect of testosterone on oxidative stress and cell damage induced by 3-nitropropionic acid in striatum of ovariectomized rats

This paper evaluates the effects of testosterone (0.5 mg/kg subcutaneously (s.c.) for 8 days) on oxidative stress and cell damage induced by 3-nitropropionic acid (20 mg/kg intraperitoneally (i.p.) for 4 days) in ovariectomized rats. Gonadectomy triggered oxidative damage and cell loss, evaluated by the detection of caspase-3, whereas 3-nitropropionic acid increased the levels of oxidative stress induced by ovariectomy and prompted cell damage characterized by enhanced levels of lactate dehydrogenase. These changes were blocked by testosterone administration. Our results support the following conclusions: i) ovariectomy triggers oxidative and cell damage via caspase-3 in the striatum; ii) 3-nitropropionic acid exacerbates oxidative stress induced by ovariectomy and leads to cell damage characterized by increased levels of lactate dehydrogenase; iii) testosterone administration decreases oxidative stress and cell damage. Additionally, these data support the hypothesis that testosterone might play an important role in the onset and development of neurodegenerative diseases.

Effect of resveratrol on 3-nitropropionic acid-induced biochemical and behavioural changes: possible neuroprotective mechanisms

Huntington's disease is a progressive, degenerative disease characterized by abnormal body movements called chorea, and a reduction of various mental abilities. 3-Nitropropionic acid, an inhibitor of complex II of the electron transport chain, causes Huntington's disease-like symptoms in rodents. Recently, it has been reported that oxidative stress, which is one of the pathological hallmarks of various neurodegenerative disorders, also plays an important role in the pathogenesis of Huntington's disease. The present study was designed to investigate effects of resveratrol, an antioxidant with cyclooxygenase I inhibitory activity, in the 3-nitropropionic acid-induced model of Huntington's disease. Intraperitoneal administration of 3-nitropropionic acid (20 mg/kg for 4 days) caused significant loss of body weight, a decline in motor function (locomotor activity, movement pattern and vacuous chewing movements) and poor retention of memory. Repeated treatment with resveratrol (5 and 10 mg/kg, orally), once daily for a period of 8 days beginning 4 days prior to 3-nitropropionic acid administration, significantly improved the 3-nitropropionic acid-induced motor and cognitive impairment. Biochemical analysis revealed that systemic 3-nitropropionic acid administration significantly increased lipid peroxidation, nitrite levels, and depleted reduced glutathione levels, and decreased succinate dehydrogenase activity in the brains of rats. The results of the present study indicate that resveratrol (5 and 10 mg/kg, orally) significantly reversed 3-nitropropionic acid-induced motor and cognitive impairment, and that the beneficial effects of resveratrol might be attributed to its antioxidant activity.

Effect of transcranial magnetic stimulation on oxidative stress induced by 3-nitropropionic acid in cortical synaptosomes

This study evaluates the effect of transcranial magnetic stimulation (TMS; 60 Hz and 0.7 mT) treatment on 3-nitropropionic acid (20 mg/kg i.p./day for 4 days)-induced oxidative stress in cortical synaptosomes of Wistar rats. The oxidative derangement was confirmed by a high level of lipid peroxidation products and protein carbonyls, together with a decreased in reduced glutathione (GSH) content, catalase and GSH-peroxidase (GSH-Px) activities. Additionally, it was observed a reduction in succinate dehydrogenase (SDH) activity. All changes were partially prevented or reversed by administration of TMS. These results show that TMS reduces oxidative stress in cortical synaptosomes, and suggest that TMS may protect neuronal and maintain synaptic integrity.

17 β-Estradiol may affect vulnerability of striatum in a 3-nitropropionic acid-induced experimental model of Huntington's disease in ovariectomized rats

The aim of present study was to clarify the role of female sex hormones in the development and course of neurodegenerative disease in an experimental model of Huntington's disease induced by 3-nitropropionic acid (NPA) (30 mg/kg intraperitoneally (i.p.)/day for 4 days) in ovariectomized rat. Gonadectomy prompted oxidative stress and cell death evaluated by the detection of caspase-3, whereas 3-nitropropionic acid enhanced the oxidative stress induced by ovariectomy and it triggered cell damage characterized by increases of LDH levels. These changes were prevented by administration of 17 beta-estradiol. Our findings suggested that: (i) ovariectomy induced oxidative stress and apoptosis in the brain; (ii) 3-nitropropionic acid exacerbated oxidative stress induced by ovariectomy and shifting cell to cell death; and (iii) 17 beta-estradiol administration decreased oxidative stress and cell death induced by ovariectomy and 3-nitropropionic acid. These results revealed that sex ovarian hormones play a important role in onset and development of neurodegenerative diseases, as well as neuroprotective effects of 17 beta-estradiol against the changes induced ovariectomy and ovariectomy plus 3-nitropropionic acid.

Transcranial magnetic stimulation attenuates cell loss and oxidative damage in the striatum induced in the 3-nitropropionic model of Huntington's disease

An investigation was conducted on the effect of transcranial magnetic field stimulation (TMS) on the free radical production and neuronal cell loss produced by 3-nitropropionic acid in rats. The effects of 3-nitropropionic acid were evaluated by examining the following changes in: the quantity of hydroperoxides and total radical-trapping antioxidant potential (TRAP), lipid peroxidation products, protein carbonyl groups, reduced glutathione (GSH) content, glutathione peroxidase (GSH-Px), catalase and succinate dehydrogenase (SDH) activities; total nitrite and cell death [morphological changes, quantification of neuronal loss and lactate dehydrogenase (LDH) levels]. Our results reveal that 3-nitropropionic acid induces oxidative and nitrosative stress in the striatum, prompts cell loss and also shows that TMS prevents the harmful effects induced by the acid. In conclusion, the results show the ability of TMS to modify neuronal response to 3-nitropropionic acid.

Treatment with Dehydroepiandrosterone Prevents Oxidative Stress Induced by 3-Nitropropionic Acid in Synaptosomes

This study evaluates the antioxidative effect of dehydroepiandrosterone (DHEA) treatment on 3-nitropropionic acid (3-NPA)-induced oxidative stress in striatal and brain cortex synaptosomes. The oxidative derangement was confirmed by a high level of lipid peroxidation products and protein carbonyls, as well as by an enhanced superoxide dismutase activity (p < 0.001). These changes were partially prevented by DHEA. Moreover, 3-NPA induced a drop in succinate dehydrogenase activity, while DHEA treatment restored the succinate dehydrogenase activity. These results show that DHEA reduces oxidative stress in synaptosomes isolated from the brain of 3-NPA-treated rats, and they suggest this neurosteroid may protect mitochondrial and maintain synaptic integrity against damage induced by this acid.

Effect of nicotine on 3-nitropropionic acid-induced oxidative stress in synaptosomes

In this paper, the effect of nicotine on the oxidative changes produced by 3-nitropropionic acid (20 mg/kg i.p./day for 4 days) in striatal and cortical synaptosomes of Wistar rats was studied. The effects of 3-nitropropionic acid were evaluated as changes in the quantity of protein carbonyl groups, lipid peroxidation products, superoxide distumase activity and reduced succinate dehydrogenase activity. All changes were prevented by the pre-injection of nicotine (1.5 mg/kg i.p./day), beginning 4 days before and continuing for 4 days after the first injection of 3-nitropropionic acid. These findings indicate that: (i) 3-nitropropionic acid induces a state of oxidative stress in cortical and striatal synaptosomes and (ii) nicotine prevents oxidative stress induced by 3-nitropropinonic acid. In conclusion, the results show the ability of nicotine to modify neural response to 3-nitropropionic acid with the protective mechanism likely involving the antioxidative processes of nicotine.

Protective effect of melatonin on 3-nitropropionic acid-induced oxidative stress in synaptosomes in an animal model of Huntington's disease

The effect of melatonin (1 mg/kg BW i.p./day) on the oxidative changes produced by 3-nitropropionic acid (20 mg/kg BW/day for 4 days) in rat striatal and cortical synaptosomes was investigated. The effects of 3-nitropropionic acid were evaluated as changes in the quantity of lipid peroxidation products, protein carbonyl groups and superoxide dismutase and succinate dehydrogenase activities. 3-Nitropropionic acid caused a rise in lipid peroxidation levels and protein carbonyls content whereas it induced a reduction in the activity of succinate dehydrogenase and triggered an enhancement in superoxide dismutase activity. These changes were prevented by previous administration of melatonin. Our results reveal: (i) 3-nitropropionic acid induces a status of oxidative stress in some brain regions of the Wistar rat; (ii) melatonin prevents the deleterious effects induced by the acid. In conclusion, the results show the ability of melatonin to modify the neural response to 3-nitropropionic acid with the protective mechanism likely involving the antioxidative processes of melatonin.