Paraquat induces apoptosis in human lymphocytes: protective and rescue effects of glucose, cannabinoids and insulin-like growth factor-1

Systemic and Lung Inflammation and Oxidative Stress Associated With Behavioral Changes Induced by Inhaled Paraquat Are Ameliorated by Carvacrol

Paraquat (PQ) is an herbicide toxin that induces injury in different organs. The anti-inflammatory and antioxidant effects of carvacrol were reported previously. The effects of carvacrol and pioglitazone (Pio) alone and their combination on inhaled PQ-induced systemic and lung oxidative stress and inflammation as well as behavioral changes were examined in rats. In this study, animals were exposed to saline (control [Ctrl]) or PQ (PQ groups) aerosols. PQ-exposed animals were treated with 0.03 mg/kg/day dexamethasone (Dexa), 20 and 80 mg/kg/day carvacrol (C-L and C-H), 5 mg/kg/day Pio, and Pio+C-L for 16 days. Inhaled PQ markedly enhanced total and differential white blood cell (WBC) counts, nitric oxide (NO), and malondialdehyde (MDA) levels but decreased catalase (CAT) and superoxide dismutase (SOD) activities and thiol levels both in the bronchoalveolar lavage fluid (BALF) and blood and increased interferon-gamma (INF-γ) and interleukin-10 (IL-10) levels in the BALF (p < 0.001 for all cases) except lymphocyte count in blood which was not significantly changed. The escape latency and traveled distance were increased in the PQ group. However, the time spent in the target quadrant in the Morris water maze (MWM) test and the duration of time latency in the dark room in the shuttle box test were reduced after receiving an electrical shock (p < 0.05-p < 0.001). Inhaled PQ-induced changes were significantly improved in carvacrol, Pio, Dexa, and especially in the combination of the Pio+C-L treated groups (p < 0.05-p < 0.001). Carvacrol and Pio improved PQ-induced changes similar to Dexa, but ameliorative effects produced by combination treatments of Pio+C-L were more prominent than Pio and C-L alone, suggesting a potentiating effect for the combination of the two agents.

Improvement of inhaled paraquat induced lung and systemic inflammation, oxidative stress and memory changes by safranal

The effects of safranal and pioglitazone alone and their combination on inhaled paraquat (PQ)-induced systemic oxidative stress and inflammation as well as behavioral changes were examined in rats. In this study, animals were exposed to saline (Ctrl) or PQ (PQ groups) aerosols. PQ exposed animals were treated with dexamethasone, 0.8 and 3.2 mg/kg/day safranal (Saf-L and Saf-H), 5 mg/kg/day pioglitazone (Pio), and Saf-L + Pio for 16 days during PQ exposure period. PQ group showed increased numbers of total and differential WBCs in blood and bronchoalveolar lavage fluid (BALF), increased malondialdehyde (MDA), in the serum BALF and brain reduced thiol, catalase (CAT), and superoxide dismutase (SOD) levels compared to the control group (for all, p < 0.001). The escape latency and traveled distance were enhanced, but the time spent in the target quadrant in the probe day and the latency to enter the dark room 3, 24, 48, and 72 h after receiving an electrical shock, (in the shuttle box test) were decreased in the PQ group (p < 0.05 to P < 0.001). In all treated groups, all measure values were improved compared to PQ group (p < 0.05 to p < 0.001). In combination treated group of Saf-L + Pio, most measured values were more improved than the Saf-L and Pio groups (p < 0.05 to p < 0.001). Saf and Pio improved PQ-induced changes similar to dexamethasone but the effects produced by combination treatments of Saf-L + Pio were more prominent than Pio and Saf-L alone, suggesting a potentiating effect for the combination of the two agents.

Roles of oxidative stress/JNK/ERK signals in paraquat-triggered hepatic apoptosis

Paraquat (PQ), a toxic and nonselective bipyridyl herbicide, is one of the most extensively used pesticides in agricultural countries. In addition to pneumotoxicity, the liver is an important target organ for PQ poisoning in humans. However, the mechanism of PQ in hepatotoxicity remains unclear. In this study, we found that exposure of rat hepatic H4IIE cells to PQ (0.1-2 mM) induced significant cytotoxicity and apoptosis, which was accompanied by mitochondria-dependent apoptotic signals, including loss of mitochondrial membrane potential (MMP), cytosolic cytochrome c release, and changes in the Bcl-2/Bax mRNA ratio. Moreover, PQ (0.5 mM) exposure markedly induced JNK and ERK1/2 activation, but not p38-MAPK. Blockade of JNK and ERK1/2 signaling by pretreatment with the specific pharmacological inhibitors SP600125 and PD98059, respectively, effectively prevented PQ-induced cytotoxicity, mitochondrial dysfunction, and apoptotic events. Additionally, PQ exposure stimulated significant oxidative stress-related signals, including reactive oxygen species (ROS) generation and intracellular glutathione (GSH) depletion, which could be reversed by the antioxidant N-Acetylcysteine (NAC). Buffering the oxidative stress response with NAC also effectively abrogated PQ-induced hepatotoxicity, MMP loss, apoptosis, and phosphorylation of JNK and ERK1/2 protein, however, the JNK or ERK inhibitors did not suppress ROS generation in PQ-treated cells. Collectively, these results demonstrate that PQ exposure induces hepatic cell toxicity and death via an oxidative stress-dependent JNK/ERK activation-mediated downstream mitochondria-regulated apoptotic pathway.

Wnt-induced secreted proteins-1 play an important role in paraquat-induced pulmonary fibrosis

Background

The objective of this article is to observe the expression of Wnt-induced secreted proteins-1 (WISP1) in paraquat (PQ)-induced pulmonary fibrosis (PF) to explore the role of WISP1.

Methods

Healthy individuals were included in the control group. Patients who had acute lung injury or PF were included in the PF group. Venous blood samples were collected from the patients on days 1 and 3 following PQ poisoning to detect the expression levels of the WISP1 gene and protein concentration. Any changes in the patients’ blood gas analysis index were reviewed. In addition, chest computed tomography (CT) and x-ray images were observed to evaluate the relationship between WISP1 expression and disease severity.

Results

The expression of the WISP1 gene and the serum WISP1 protein concentration were higher in patients with PQ poisoning combined with PF than in patients without PF (P < 0.01). Serum PQ concentration was positively correlated with WISP1 gene expression (r = 0.621, P < 0.01), and serum WISP1 protein concentration (r = 0.596, P < 0.01) was considered a risk factor [odds ratio (OR) = 4.356, P < 0.05] for PQ-induced PF. Concurrently, the results of the adjusted and non-adjusted OR value for WISP1 gene expression and WISP1 protein concentration on day 1 was, respectively, as follows: OR = 12.797, 95% confidence interval (CI) (2.478–66.076), P = 0.002, OR’ = 11.353, P = 0.005; and OR = 1.545, 95% CI (1.197–1.995), P = 0.001, OR’ = 1.487, P = 0.003. The CT scan of a 20-year-old male with PQ-induced PF (20 ml) was observed, and it showed a typical hyaline-like lesion in the lungs on day 22 after poisoning; on day 33 after poisoning, the lungs showed localised consolidation combined with air bronchography.

Conclusion

The expression of WISP1 was higher in the patients with PQ-induced PF compared with the patients without PF. Accordingly, WISP1 plays an important role in PQ-induced PF.

Novel Psychoactive Substances: The Razor's Edge between Therapeutical Potential and Psychoactive Recreational Misuse

BACKGROUND

Novel psychoactive substances (NPS) are compounds of natural and synthetic origin, similar to traditional drugs of abuse. NPS are involved in a contemporary trend whose origin lies in a thinner balance between legitimate therapeutic drug research and legislative control. The contemporary NPS trend resulted from the replacement of MDMA by synthetic cathinones in 'ecstasy' during the 2000s. The most common NPS are synthetic cannabinoids and synthetic cathinones. Interestingly, during the last 50 years, these two classes of NPS have been the object of scientific research for a set of health conditions.

METHODS

Searches were conducted in the online database PubMed using boolean equations.

RESULTS

Synthetic cannabinoids displayed protective and therapeutic effects for inflammatory, neurodegenerative and oncologic pathologies, activating the immune system and reducing inflammation. Synthetic cathinones act similarly to amphetamine-type stimulants and can be used for depression and chronic fatigue.

CONCLUSIONS

Despite the scientific advances in this field of research, pharmacological application of NPS is being jeopardized by fatalities associated with their recreational use. This review addresses the scientific achievements of these two classes of NPS and the toxicological data, ending with a reflection on Illicit and NPS control frames.

The Effect of Ulinastatin to the Learning and Memory in Zebrafish

Previous study indicated that Ulinastatin (UTI) increased glutamine uptake by upregulation of glutamate transporters in astrocytes. These glutamate transporters have important role to improve cognitive function in hippocampus. In this study, we wanted to demonstrate whether UTI could improve learning and memory by using zebrafish behavior model and bio-markers. Zebrafish were 6-8 months of age and were 2.5-3.5 cm long. They were divided into four groups by control, 1X PBS-injected control, UTI 10,000, and 50,000 injected group. All PBS and UTI injected zebrafish were anesthetized by Tricainemethanesulphonate. We measured total time, distance moved, and frequency in each compartment of T-maze. We also measured the expression levels of glutamate transporter levels and cognitive bio-markers such as c-fos, c-jun, BDNF. UTI affected the learning and memory in zebrafish in a dose-dependent manner. In 50,000 unit/kg UTI-treated zebrafish, there were increases of time, distance, and frequency in target compartment. In 50,000 unit/kg UTI-treated zebrafish, there was an increase of time in target compartment. There was no difference among control, PBS-injected, and UTI 10,000 unit/kg-treated groups. EAAT4 glutamate transporter, c-fos and BDNF were significantly increased in 50,000 unit/kg UTI-treated group. UTI-enhanced learning and memory in zebrafish. The expressions of EAAT4 glutamate transporter, c- fos and BDNF in zebrafish were highly correlated may play a role.

Association between liberal oxygen therapy and mortality in patients with paraquat poisoning: A multi-center retrospective cohort study

Paraquat (N, N'-dimethyl-4, 4'-bipyridinium dichloride, PQ) intoxication is a common cause of lethal poisoning. This study aimed to identify the risk of using liberal oxygen therapy in patients with PQ poisoning. This was a multi-center retrospective cohort study involving four medical institutions in Taiwan. Data were extracted from the Chang Gung Research Database (CGRD) from January 2004 to December 2016. Patients confirmed to have PQ intoxication with a urine PQ concentration ≥ 5 ppm were analyzed. Patients who received oxygen therapy before marked hypoxia (SpO2 ≥ 90%) were defined as receiving liberal oxygen therapy. The association between mortality and patient demographics, blood paraquat concentration (ppm), and liberal oxygen therapy were analyzed. A total of 416 patients were enrolled. The mortality rate was higher in the liberal oxygen therapy group (87.8% vs. 73.7%, P = 0.007), especially in 28-day mortality (adjusted odds ratio [aOR]: 4.71, 95% confidence interval [CI]: 1.533–14.471) and overall mortality (aOR: 5.97, 95% CI: 1.692–21.049) groups. Mortality in patients with PQ poisoning was also associated with age (aOR: 1.04, 95% CI: 1.015–1.073), blood creatinine level (aOR: 1.49, 95% CI: 1.124–1.978), and blood paraquat concentration (ppm) (aOR, 1.51; 95% CI: 1.298–1.766). Unless the evidence of hypoxia (SpO2 < 90%) is clear, oxygen therapy should be avoided because it is associated with increased mortality.

Chemically Induced Models of Parkinson's Disease: History and Perspectives for the Involvement of Ferroptosis

Ferroptosis is a newly discovered form of necrotic cell death characterized by its dependency on iron and lipid peroxidation. Ferroptosis has attracted much attention recently in the area of neurodegeneration since the involvement of ferroptosis in Parkinson’s disease (PD), a major neurodegenerative disease, has been indicated using animal models. Although PD is associated with both genetic and environmental factors, sporadic forms of PD account for more than 90% of total PD. Following the importance of environmental factors, various neurotoxins are used as chemical inducers of PD both in vivo and in vitro. In contrast to other neurodegenerative diseases such as Alzheimer’s and Huntington’s diseases (AD and HD), many of the characteristics of PD can be reproduced in vivo by the use of specific neurotoxins. Given the indication of ferroptosis in PD pathology, several studies have been conducted to examine whether ferroptosis plays role in the loss of dopaminergic neurons in PD. However, there are still few reports showing an authentic form of ferroptosis in neuronal cells during exposure to the neurotoxins used as PD inducers. In this review article, we summarize the history of the uses of chemicals to create PD models in vivo and in vitro. Besides, we also survey recent reports examining the possible involvement of ferroptosis in chemical models of PD.

The PARK2 Mutation Associated with Parkinson's Disease Enhances the Vulnerability of Peripheral Blood Lymphocytes to Paraquat

Parkinson's disease (PD) is the second most common neurodegenerative disease in middle-aged and elderly people. However, the etiology and pathogenesis of PD are still unclear and there is a lack of reliable biomarkers for early molecular diagnosis. Parkin (encoded by PARK2) is a ubiquitin E3 ligase that participates in mitochondrial homeostasis, the ubiquitin-proteasome pathway, oxidative stress response, and cell death pathways, which are involved in the pathogenesis of PD. However, Parkin is also expressed in peripheral blood lymphocytes (PBLs). In this study, permanent lymphocyte lines were established from the peripheral blood of sporadic PD (sPD) patients, PARK2 mutation carriers, and healthy controls. Reactive oxygen species (ROS), function of the mitochondrial respiratory chain complex I, and apoptosis were analyzed in the PBLs. There was no significant difference in ROS, mitochondrial respiratory chain complex I, and apoptosis between the experimental groups and the control group without paraquat treatment. Compared with the control group of healthy subjects, we found an increase of ROS (control 100 ± 0, sPD 275.53 ± 79.11, and C441R 340 ± 99.67) and apoptosis, as well as a decline in the function of mitochondrial respiratory chain complex I in PBLs of PARK2 mutation carriers and sPD after the treatment of paraquat (control 0.65 ± 0.08, sPD 0.44 ± 0.08, and C441R 0.32 ± 0.08). Moreover, overexpression of the wild-type (WT) PARK2 in HeLa cells and immortalized PBLs could rescue mitochondrial function and partially inhibit apoptosis following paraquat treatment, while the C441R mutation could not. Thus, ROS levels, activity of mitochondrial respiratory chain complex I, and apoptosis of PBLs are potential diagnostic biomarkers of PD.

Nimodipine attenuates the parkinsonian neurotoxin, MPTP-induced changes in the calcium binding proteins, calpain and calbindin

We have recently demonstrated neuroprotective abilities of nimodipine, an L-type voltage dependent calcium channel (VDCC) blocker in cellular and animal models of Parkinson's disease (PD). To understand the calcium regulatory mechanisms in the disease pathogenesis, the present study examined calcium regulatory proteins calbindin and calpain mRNA and protein levels employing quantitative PCR and western blot in 1-methyl-4-phenyl pyridinium ion (MPP⁺)-treated SH-SY5Y cell lines and in the striatum of mice treated with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). mRNA and protein levels of calbindin were lower, while that of calpain were higher in MPP⁺-treated SH-SY5Y cells and MPTP-treated mouse striatum as compared to their respective controls. Nimodipine pretreatment significantly attenuated these effects in the parkinsonian neurotoxin-treated SH-SY5Y cell line and in the mouse striatum. The activities of the apoptotic mediator, caspase-3 and calpain were increased in the neurotoxin-treated groups as compared to their respective controls, which was ameliorated by nimodipine pretreatment. These results suggest that parkinsonian neurotoxin-mediated dopaminergic neuronal death might involve defects in calcium regulatory proteins that control intracellular calcium homeostasis, and these could be corrected by inhibiting L-type VDCC activity. These findings support the notion that hypertensive patients who are on long-term intake of dihydropyridine have reduced risk for PD.

Early Metabolome Profiling and Prognostic Value in Paraquat-Poisoned Patients: Based on Ultraperformance Liquid Chromatography Coupled To Quadrupole Time-of-Flight Mass Spectrometry

Paraquat (PQ) has caused countless deaths throughout the world. There remains no effective treatment for PQ poisoning. Here we study the blood metabolome of PQ-poisoned patients using ultraperformance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry (UPLC/Q-TOF MS). Patients were divided into groups according to blood PQ concentration. Healthy subjects served as controls. Metabolic features were statistically analyzed using multivariate pattern-recognition techniques to identify the most important metabolites. Selected metabolites were further compared with a series of clinical indexes to assess the prognostic value. PQ-poisoned patients showed substantial differences compared with healthy subjects. Based on variable of importance in the project (VIP) values and statistical analysis, 17 metabolites were selected and identified. These metabolites well-classified low PQ-poisoned patients, high PQ-poisoned patients, and healthy subjects, which was better than that of a complete blood count (CBC). Among the 17 metabolites, 20:3/18:1-PC (PC), LPA (0:0/16:0) (LPA), 19-oxo-deoxycorticosterone (19-oxo-DOC), and eicosapentaenoic acid (EPA) had prognostic value. In particular, EPA was the most sensitive one. Besides, the levels of EPA was correlated with LPA and 19-oxo-DOC. If EPA was excessively consumed, then prognosis was poor. In conclusion, the serum metabolome is substantially perturbed by PQ poisoning. EPA is the most important biomarker in early PQ poisoning.

Effects of hemoperfusion and continuous renal replacement therapy on patient survival following paraquat poisoning

Mortality in patients with paraquat (PQ) poisoning is related to plasma PQ levels. Concentrations lower than 5,000 ng/mL are considered critical but curable. This study assessed the effects of hemoperfusion (HP) and continuous renal replacement therapy (CRRT) on the survival of PQ-poisoned patients with plasma PQ levels below 5,000ng/mL. We analyzed the records of 164 patients with PQ poisoning who were treated at the First Affiliated Hospital of Wenzhou Medical University in China between January 2011 and May 2015. We divided these patients into six sub-groups based on baseline plasma PQ levels and treatment, compared their clinical characteristics, and analyzed their survival rates. Patient sub-groups did not differ in terms of age, sex, time between poisoning and hospital admission, or time to first gavage. Biochemical indicators improved over time in all sub-groups following treatment, and the combined HP and CRRT treatment yielded better results than HP or CRRT alone. Fatality rates in the three treatment sub-groups did not differ among patients with baseline plasma PQ levels of 50–1,000 ng/mL, but in patients with 1,000–5,000 ng/mL levels, the mortality rate was 59.2% (HP treatment group), 48% (CRRT treatment group), and 37.9% (combined treatment group). Mortality rates were higher 10–30 days after hospitalization than in the first 10 days after admission. In the early stages of PQ poisoning, CRRT is effective in reducing patient fatality rates, particularly when combined with HP. Our data could be useful in increasing survival in acute PQ poisoning patients.

Crosstalk between Mitochondrial Fission and Oxidative Stress in Paraquat-Induced Apoptosis in Mouse Alveolar Type II Cells

Paraquat (PQ), as a highly effective and nonselective herbicide, induces cell apoptosis through generation of superoxide anions which forms reactive oxygen species (ROS). Mitochondria, as regulators for cellular redox signaling, have been proved to play an important role in PQ-induced cell apoptosis. This study aimed to evaluate whether and how mitochondrial fission interacts with oxidative stress in PQ-induced apoptosis in mouse alveolar type II (AT-II) cells. Firstly, we demonstrated that PQ promoted apoptosis and release of cytochrome-c (Cyt-c). Furthermore, we showed that PQ broke down mitochondrial network, enhanced the expression of fission-related proteins, increased Drp1 mitochondrial translocation while decreased the expression of fusion-related proteins in AT-II cells. Besides, inhibiting mitochondrial fission using mdivi-1, a selective inhibitor of Drp1, markedly attenuated PQ-induced apoptosis, release of Cyt-c and the generation of ROS. These results indicate that mitochondrial fission involves in PQ-induced apoptosis. Further study demonstrated that antioxidant ascorbic acid inhibited Drp1 mitochondrial translocation, mitochondrial fission and attenuated PQ-induced apoptosis. Overall, our findings suggest that mitochondrial fission interplays with ROS in PQ-induced apoptosis in mouse AT-II cells and mitochondrial fission could serve as a potential therapeutic target in PQ poisoning.

Minocycline protects, rescues and prevents knockdown transgenic parkin Drosophila against paraquat/iron toxicity: Implications for autosomic recessive juvenile parkinsonism

Autosomal recessive Juvenile Parkinsonism (AR-JP) is a chronic, progressive neurodegenerative disorder caused by mutation in the PARKIN gene, and invariably associated with dopaminergic (DAergic) neuronal loss and brain iron accumulation. Since current medical therapy is symptomatic and lacks significant disease-modifying effects, other treatment approaches are urgently needed it. In the present work, we investigate the role of minocycline (MC) in paraquat (PQ)/iron-induced neurotoxicity in the Drosophila TH>parkin-RNAi/+ (w[*]; UAS-parkin-RNAi; TH-GAL4) fly and have shown the following: (i) MC increased life span and restored the locomotor activity of knockdown (KD) transgenic parkin flies in comparison with the control (vehicle) group; (ii) MC at low (0.1 and 0.3mM) and middle (0.5mM) concentrations protected, rescued and prevented KD parkin Drosophila against PQ toxicity. However, MC at high (1mM) concentration aggravated the toxic effect of PQ; (iii) MC protected and rescued DAergic neurons against the PQ toxic effect according to tyrosine hydroxylase (TH)>green-fluorescent protein (GFP) reporter protein microscopy and anti-TH Western blotting analysis; (iv) MC protected DAergic neurons against PQ/iron toxicity; (v) MC significantly abridged lipid peroxidation (LPO) in the protection, rescue and prevention treatment in TH>parkin-RNAi/+ flies against PQ or iron alone or combined (PQ/iron)-induced neuronal oxidative stress (OS). Our results suggest that MC exerts neuroprotection against PQ/iron-induced OS in DAergic neurons most probably by the scavenging activity of reactive oxygen species (ROS), and by chelating iron. Therefore, MC might be a potential therapeutic drug to delay, revert, or prevent AR-JP.

An Effective Machine Learning Approach for Prognosis of Paraquat Poisoning Patients Using Blood Routine Indexes

The early identification of toxic paraquat (PQ) poisoning in patients is critical to ensure timely and accurate prognosis. Although plasma PQ concentration has been reported as a clinical indicator of PQ poisoning, it is not commonly applied in practice due to the inconvenient necessary instruments and operation. In this study, we explored the use of blood routine indexes to identify the degree of PQ toxicity and/or diagnose PQ poisoning in patients via machine learning approach. Specifically, we developed a method based on support vector machine combined with the feature selection technique to accurately predict PQ poisoning risk status, then tested the method on 79 (42 male and 37 female; 41 living and 38 deceased) patients. The detection method was rigorously evaluated against a real-world data set to determine its accuracy, sensitivity and specificity. Feature selection was also applied to identify the factors correlated with risk status, and the results showed that there are significant differences in blood routine indexes between dead and living PQ-poisoned individuals (p-value < 0.01). Feature selection also showed that the most important correlated indexes are white blood cell and neutrophils. In conclusion, the toxicity or prognosis of PQ poisoning can be preliminarily ascertained by blood routine testing without PQ concentration data, representing an additional tool and innovative approach to assess the prognosis of PQ poisoning.

Nimodipine, an L-type calcium channel blocker attenuates mitochondrial dysfunctions to protect against 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced Parkinsonism in mice

Parkinson's disease (PD), the most common progressive neurodegenerative movement disorder, results from loss of dopaminergic neurons of substantia nigra pars compacta. These neurons exhibit Cav1.3 channel-dependent pacemaking activity. Epidemiological studies suggest reduced risk for PD in population under long-term antihypertensive therapy with L-type calcium channel antagonists. These prompted us to investigate nimodipine, an L-type calcium channel blocker for neuroprotective effect in cellular and animal models of PD. Nimodipine (0.1-10 μM) significantly attenuated 1-methyl-4-phenyl pyridinium ion-induced loss in mitochondrial morphology, mitochondrial membrane potential and increases in intracellular calcium levels in SH-SY5Y neuroblastoma cell line as measured respectively employing Mitotracker green staining, TMRM, and Fura-2 fluorescence, but only a feeble neuroprotective effect was observed in MTT assay. Nimodipine dose-dependently reduced 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced parkinsonian syndromes (akinesia and catalepsy) and loss in swimming ability in Balb/c mice. It attenuated MPTP-induced loss of dopaminergic tyrosine hydroxylase positive neurons in substantia nigra, improved mitochondrial oxygen consumption and inhibited reactive oxygen species production in the striatal mitochondria measured using dichlorodihydrofluorescein fluorescence, but failed to block striatal dopamine depletion. These results point to an involvement of L-type calcium channels in MPTP-induced dopaminergic neuronal death in experimental parkinsonism and more importantly provide evidences for nimodipine to improve mitochondrial integrity and function.

Prognosis and survival analysis of paraquat poisoned patients based on improved HPLC-UV method

Paraquat (PQ) has caused deaths of numerous people around the world. In order to assess the lethal plasma concentration, the patients who acquired acute PQ intoxication were analyzed by plasma concentration monitoring. The plasma PQ concentrations were determined by high performance liquid chromatography (HPLC) which used 5-bromopyrimidine as internal standard and trichloroacetic acid-methanol (1:9) as protein precipitant. The liver, kidney and coagulation function were determined by automatic biochemical analyzer. According to plasma PQ concentration, 90 patients were divided into four groups: trace PQ group (<50ng/mL), low PQ group (<1000ng/mL), medium PQ group (1000-5000ng/mL) and high PQ group (>5000ng/mL). The clinical data from the four groups was statistically analyzed. The results showed the developed HPLC methods exhibited a high degree of accuracy and good linearity within 50-25000ng/mL (R=0.9998). The Spearman's correlation analysis showed PQ concentration had a strong relationship to total bilirubin, direct bilirubin, aspartic transaminase, urea nitrogen, prothrombin time, prothrombin activity, and international normalized ratio (P<0.01). The cured or survival PQ poisoned patients among the trace PQ group, the low PQ group, the medium PQ group, and the high PQ group were 19/19 (100%), 19/21 (90.47%), 11/25 (44.0%), and 0/25 (0%) respectively. The mean hospital days were (10.37±8.04), (18.76±12.06), (16.76±14.44), and (4.04±5.41) days respectively. The Cox regression analysis indicated that plasma PQ concentration was highly related to prognosis (P<0.05). In conclusion, no patient presenting with a PQ concentration over 5000ng/mL survived. The plasma PQ level is related to liver, kidney and coagulation function, which can be used as an important clinical index to judge the prognosis of PQ poisoned patients.

CHEMICAL COMPOUNDS

Paraquat (PubChem CID: 15938), 5-bromopyrimidine (PubChem CID: 78344), acetonitrile (PubChem CID: 6342), sodium dihydrogen phosphate (PubChem CID: 23672064), sodium heptanesulfonate (PubChem CID: 23672332), methylprednisolone (PubChem CID: 6741), cyclophosphamide (PubChem CID: 2907).

Causes of genome instability: the effect of low dose chemical exposures in modern society

Genome instability is a prerequisite for the development of cancer. It occurs when genome maintenance systems fail to safeguard the genome's integrity, whether as a consequence of inherited defects or induced via exposure to environmental agents (chemicals, biological agents and radiation). Thus, genome instability can be defined as an enhanced tendency for the genome to acquire mutations; ranging from changes to the nucleotide sequence to chromosomal gain, rearrangements or loss. This review raises the hypothesis that in addition to known human carcinogens, exposure to low dose of other chemicals present in our modern society could contribute to carcinogenesis by indirectly affecting genome stability. The selected chemicals with their mechanisms of action proposed to indirectly contribute to genome instability are: heavy metals (DNA repair, epigenetic modification, DNA damage signaling, telomere length), acrylamide (DNA repair, chromosome segregation), bisphenol A (epigenetic modification, DNA damage signaling, mitochondrial function, chromosome segregation), benomyl (chromosome segregation), quinones (epigenetic modification) and nano-sized particles (epigenetic pathways, mitochondrial function, chromosome segregation, telomere length). The purpose of this review is to describe the crucial aspects of genome instability, to outline the ways in which environmental chemicals can affect this cancer hallmark and to identify candidate chemicals for further study. The overall aim is to make scientists aware of the increasing need to unravel the underlying mechanisms via which chemicals at low doses can induce genome instability and thus promote carcinogenesis.

The effect of environmental chemicals on the tumor microenvironment

Potentially carcinogenic compounds may cause cancer through direct DNA damage or through indirect cellular or physiological effects. To study possible carcinogens, the fields of endocrinology, genetics, epigenetics, medicine, environmental health, toxicology, pharmacology and oncology must be considered. Disruptive chemicals may also contribute to multiple stages of tumor development through effects on the tumor microenvironment. In turn, the tumor microenvironment consists of a complex interaction among blood vessels that feed the tumor, the extracellular matrix that provides structural and biochemical support, signaling molecules that send messages and soluble factors such as cytokines. The tumor microenvironment also consists of many host cellular effectors including multipotent stromal cells/mesenchymal stem cells, fibroblasts, endothelial cell precursors, antigen-presenting cells, lymphocytes and innate immune cells. Carcinogens can influence the tumor microenvironment through effects on epithelial cells, the most common origin of cancer, as well as on stromal cells, extracellular matrix components and immune cells. Here, we review how environmental exposures can perturb the tumor microenvironment. We suggest a role for disrupting chemicals such as nickel chloride, Bisphenol A, butyltins, methylmercury and paraquat as well as more traditional carcinogens, such as radiation, and pharmaceuticals, such as diabetes medications, in the disruption of the tumor microenvironment. Further studies interrogating the role of chemicals and their mixtures in dose-dependent effects on the tumor microenvironment could have important general mechanistic implications for the etiology and prevention of tumorigenesis.

Paraquat Induces Apoptosis through a Mitochondria-Dependent Pathway in RAW264.7 Cells

Paraquat dichloride (N,N-dimethyl-4-4′-bipiridinium, PQ) is an extremely toxic chemical that is widely used in herbicides. PQ generates reactive oxygen species (ROS) and causes multiple organ failure. In particular, PQ has been reported to be an immunotoxic agrochemical compound. PQ was shown to decrease the number of macrophages in rats and suppress monocyte phagocytic activity in mice. However, the effect of PQ on macrophage cell viability remains unclear. In this study, we evaluated the cytotoxic effect of PQ on the mouse macrophage cell line, RAW264.7 and its possible mechanism of action. RAW264.7 cells were treated with PQ (0, 75, and 150 μM), and cellular apoptosis, mitochondrial membrane potential (MMP), and intracellular ROS levels were determined. Morphological changes to the cell nucleus and cellular apoptosis were also evaluated by DAPI and Annexin V staining, respectively. In this study, PQ induced apoptotic cell death by dose-dependently decreasing MMP. Additionally, PQ increased the cleaved form of caspase-3, an apoptotic marker. In conclusion, PQ induces apoptosis in RAW264.7 cells through a ROS-mediated mitochondrial pathway. Thus, our study improves our knowledge of PQ-induced toxicity, and may give us a greater understanding of how PQ affects the immune system.

Ulinastatin suppresses endoplasmic reticulum stress and apoptosis in the hippocampus of rats with acute paraquat poisoning

Lung injury is the main manifestation of paraquat poisoning. Few studies have addressed brain damage after paraquat poisoning. Ulinastatin is a protease inhibitor that can effectively stabilize lysosomal membranes, prevent cell damage, and reduce the production of free radicals. This study assumed that ulinastatin would exert these effects on brain tissues that had been poisoned with paraquat. Rat models of paraquat poisoning were intraperitoneally injected with ulinastatin. Simultaneously, rats in the control group were administered normal saline. Hematoxylin-eosin staining showed that most hippocampal cells were contracted and nucleoli had disappeared in the paraquat group. Fewer cells in the hippocampus were concentrated and nucleoli had disappeared in the ulinastatin group. Western blot assay showed that expressions of GRP78 and cleaved-caspase-3 were significantly lower in the ulinastatin group than in the paraquat group. Immunohistochemical findings showed that CHOP immunoreactivity was significantly lower in the ulinastatin group than in the paraquat group. Terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling staining showed that the number of apoptotic cells was reduced in the paraquat and ulinastatin groups. These data confirmed that endoplasmic reticular stress can be induced by acute paraquat poisoning. Ulinastatin can effectively inhibit this stress as well as cell apoptosis, thereby exerting a neuroprotective effect.

Natural antioxidant betanin protects rats from paraquat-induced acute lung injury interstitial pneumonia

The effect of betanin on a rat paraquat-induced acute lung injury (ALI) model was investigated. Paraquat was injected intraperitoneally at a single dose of 20 mg/kg body weight, and betanin (25 and 100 mg/kg/d) was orally administered 3 days before and 2 days after paraquat administration. Rats were sacrificed 24 hours after the last betanin dosage, and lung tissue and bronchoalveolar lavage fluid (BALF) were collected. In rats treated only with paraquat, extensive lung injury characteristic of ALI was observed, including histological changes, elevation of lung : body weight ratio, increased lung permeability, increased lung neutrophilia infiltration, increased malondialdehyde (MDA) and myeloperoxidase (MPO) activity, reduced superoxide dismutase (SOD) activity, reduced claudin-4 and zonula occluden-1 protein levels, increased BALF interleukin (IL-1) and tumor necrosis factor (TNF)-α levels, reduced BALF IL-10 levels, and increased lung nuclear factor kappa (NF-κB) activity. In rats treated with betanin, paraquat-induced ALI was attenuated in a dose-dependent manner. In conclusion, our results indicate that betanin attenuates paraquat-induced ALI possibly via antioxidant and anti-inflammatory mechanisms. Thus, the potential for using betanin as an auxilliary therapy for ALI should be explored further.

An efficient machine learning approach for diagnosis of paraquat-poisoned patients

Numerous people die of paraquat (PQ) poisoning because they were not diagnosed and treated promptly at an early stage. Till now, determination of PQ levels in blood or urine is still the only way to confirm the PQ poisoning. In order to develop a new diagnostic method, the potential of machine learning technique was explored in this study. A newly developed classification technique, extreme learning machine (ELM), was taken to discriminate the PQ-poisoned patients from the healthy controls. 15 PQ-poisoned patients recruited from The First Affiliated Hospital of Wenzhou Medical University who had a history of direct contact with PQ and 16 healthy volunteers were involved in the study. The ELM method is examined based on the metabolites of blood samples determined by gas chromatography coupled with mass spectrometry in terms of classification accuracy, sensitivity, specificity and AUC (area under the receiver operating characteristic (ROC) curve) criterion, respectively. Additionally, the feature selection was also investigated to further boost the performance of ELM and the most influential feature was detected. The experimental results demonstrate that the proposed approach can be regarded as a success with the excellent classification accuracy, AUC, sensitivity and specificity of 91.64%, 0.9156%, 91.33% and 91.78%, respectively. Promisingly, the proposed method might serve as a new candidate of powerful tools for diagnosis of PQ-poisoned patients with excellent performance.

Clearance rate and BP-ANN model in paraquat poisoned patients treated with hemoperfusion

In order to investigate the effect of hemoperfusion (HP) on the clearance rate of paraquat (PQ) and develop a clearance model, 41 PQ-poisoned patients who acquired acute PQ intoxication received HP treatment. PQ concentrations were determined by high performance liquid chromatography (HPLC). According to initial PQ concentration, study subjects were divided into two groups: Low-PQ group (0.05–1.0 μg/mL) and High-PQ group (1.0–10 μg/mL). After initial HP treatment, PQ concentrations decreased in both groups. However, in the High-PQ group, PQ levels remained in excess of 0.05 μg/mL and increased when the second HP treatment was initiated. Based on the PQ concentrations before and after HP treatment, the mean clearance rate of PQ calculated was 73 ± 15%. We also established a backpropagation artificial neural network (BP-ANN) model, which set PQ concentrations before HP treatment as input data and after HP treatment as output data. When it is used to predict PQ concentration after HP treatment, high prediction accuracy (R = 0.9977) can be obtained in this model. In conclusion, HP is an effective way to clear PQ from the blood, and the PQ concentration after HP treatment can be predicted by BP-ANN model.

Dmp53, basket and drICE gene knockdown and polyphenol gallic acid increase life span and locomotor activity in a Drosophila Parkinson's disease model

Understanding the mechanism(s) by which dopaminergic (DAergic) neurons are eroded in Parkinson's disease (PD) is critical for effective therapeutic strategies. By using the binary tyrosine hydroxylase (TH)-Gal4/UAS-X RNAi Drosophila melanogaster system, we report that Dmp53, basket and drICE gene knockdown in dopaminergic neurons prolong life span (p < 0.05; log-rank test) and locomotor activity (p < 0.05; χ(2) test) in D. melanogaster lines chronically exposed to (1 mM) paraquat (PQ, oxidative stress (OS) generator) compared to untreated transgenic fly lines. Likewise, knockdown flies displayed higher climbing performance than control flies. Amazingly, gallic acid (GA) significantly protected DAergic neurons, ameliorated life span, and climbing abilities in knockdown fly lines treated with PQ compared to flies treated with PQ only. Therefore, silencing specific gene(s) involved in neuronal death might constitute an excellent tool to study the response of DAergic neurons to OS stimuli. We propose that a therapy with antioxidants and selectively "switching off" death genes in DAergic neurons could provide a means for pre-clinical PD individuals to significantly ameliorate their disease condition.

The bad, the good, and the ugly about oxidative stress

Alzheimer's disease (AD), Parkinson's disease (PD), and cancer (e.g., leukemia) are the most devastating disorders affecting millions of people worldwide. Except for some kind of cancers, no effective and/or definitive therapeutic treatment aimed to reduce or to retard the clinic and pathologic symptoms induced by AD and PD is presently available. Therefore, it is urgently needed to understand the molecular basis of these disorders. Since oxidative stress (OS) is an important etiologic factor of the pathologic process of AD, PD, and cancer, understanding how intracellular signaling pathways respond to OS will have a significant implication in the therapy of these diseases. Here, we propose a model of minimal completeness of cell death signaling induced by OS as a mechanistic explanation of neuronal and cancer cell demise. This mechanism might provide the basis for therapeutic design strategies. Finally, we will attempt to associate PD, cancer, and OS. This paper critically analyzes the evidence that support the “oxidative stress model” in neurodegeneration and cancer.

Medical management of paraquat ingestion

Poisoning by paraquat herbicide is a major medical problem in parts of Asia while sporadic cases occur elsewhere. The very high case fatality of paraquat is due to inherent toxicity and lack of effective treatments. We conducted a systematic search for human studies that report toxicokinetics, mechanisms, clinical features, prognosis and treatment. Paraquat is rapidly but incompletely absorbed and then largely eliminated unchanged in urine within 12-24 h. Clinical features are largely due to intracellular effects. Paraquat generates reactive oxygen species which cause cellular damage via lipid peroxidation, activation of NF-κB, mitochondrial damage and apoptosis in many organs. Kinetics of distribution into these target tissues can be described by a two-compartment model. Paraquat is actively taken up against a concentration gradient into lung tissue leading to pneumonitis and lung fibrosis. Paraquat also causes renal and liver injury. Plasma paraquat concentrations, urine and plasma dithionite tests and clinical features provide a good guide to prognosis. Activated charcoal and Fuller's earth are routinely given to minimize further absorption. Gastric lavage should not be performed. Elimination methods such as haemodialysis and haemoperfusion are unlikely to change the clinical course. Immunosuppression with dexamethasone, cyclophosphamide and methylprednisolone is widely practised, but evidence for efficacy is very weak. Antioxidants such as acetylcysteine and salicylate might be beneficial through free radical scavenging, anti-inflammatory and NF-κB inhibitory actions. However, there are no published human trials. The case fatality is very high in all centres despite large variations in treatment.

Endogenous TDP-43 localized to stress granules can subsequently form protein aggregates

TDP-43 proteinopathies are characterized by loss of nuclear TDP-43 and accumulation of the protein in the cytosol as ubiquitinated protein aggregates. These protein aggregates may have an important role in subsequent neuronal degeneration in motor neuron disease, frontotemporal dementia and potentially other neurodegenerative diseases. Although the cellular mechanisms driving the abnormal accumulation of TDP-43 are not understood, recent studies have shown that an early change to TDP-43 metabolism in disease may be accumulation in cytosolic RNA stress granules (SGs). However, it is unclear whether the TDP-43 in these SGs progresses to become irreversible protein aggregates as observed in patients. We have shown recently that paraquat-treated cells are a useful model for examining TDP-43 SG localization. In this study, we used the paraquat model to examine if endogenous TDP-43 in SGs can progress to more stable protein aggregates. We found that after treatment of HeLa cells overnight with paraquat, TDP-43 co-localized to SGs together with the ubiquitous SG marker, human antigen R (HuR). However, after a further incubation in paraquat-free, conditioned medium for 6h, HuR-positive SGs were rarely detected yet TDP-43 positive aggregates remained present. The majority of these TDP-43 aggregates were positive for ubiquitin. Further evidence for persistence of TDP-43 aggregates was obtained by treating cultures with cycloheximide after paraquat treatment. Cycloheximide abolished nearly all cytosolic HuR aggregation (SGs) but large TDP-43-positive aggregates remained. Finally, we showed that addition of ERK and JNK inhibitors together with paraquat blocked TDP-43-positive SG formation, while treatment with inhibitors after 24h paraquat exposure failed to reverse the TDP-43 accumulation. This failure was most likely due to the addition of inhibitors after maximal activation of the kinases at 4h post-paraquat treatment. These findings provide strong evidence that once endogenous TDP-43 accumulates in SGs, it has the potential to progress to stable protein aggregates as observed in neurons in TDP-43 proteinopathies. This may provide a therapeutic opportunity to inhibit the transition of TDP-43 from SG protein to aggregate.

Hydrogen peroxide modulates immunoglobulin expression by targeting the 3'Igh regulatory region through an NFκB-dependent mechanism

Reactive oxygen species such as hydrogen peroxide (H(2)O(2)) appear to play a role in signal transduction in immune cells and have been shown to be synthesized upon antigen-mediated activation and to facilitate cellular activation in B- and T-cells. However, an effect of H(2)O(2) on B-cell function (i.e. immunoglobulin (Ig) expression) has been less well-characterized. The effects of H(2)O(2) exposure on lymphocytes may be partly mediated by oxidative modulation of the NFκB signal transduction pathway, which also plays a role in Ig heavy chain (Igh) gene expression. Igh transcription in B lymphocytes is an essential step in antibody production and is governed through a complex interaction of several regulatory elements, including the 3'Igh regulatory region (3'IghRR). Utilizing an in vitro mouse B-cell line model, this study demonstrates that exposure to low μM concentrations of H(2)O(2) can enhance 3'IghRR-regulated transcriptional activity and Igh gene expression, while either higher concentrations of H(2)O(2) or the expression of a degradation resistant inhibitory κB (IκBα super-repressor) can abrogate this effect. Furthermore, suppressive H(2)O(2) concentrations increased protein levels of the p50 NFκB sub-unit, IκBα, and an IκBα immunoreactive band which was previously characterized as an IκBα cleavage product exhibiting stronger inhibitory function than native IκBα. Taken together, these observations suggest that exposure of B lymphocytes to H(2)O(2) can alter Igh transcriptional activity and Ig expression in a complex biphasic manner which appears to be mediated by NFκB and altered 3'IghRR activity. These results may have significant implications to disease states previously associated with the 3'IghRR.

Life span and locomotor activity modification by glucose and polyphenols in Drosophila melanogaster chronically exposed to oxidative stress-stimuli: implications in Parkinson's disease

Previous studies have shown that polyphenols might be potent neuroprotective agents in Drosophila melanogaster, a valid model for PD, acutely treated with oxidative stress-stimulants. This study report for the first time that polyphenols exposure prolong life span (P < 0.05 by log-rang test) and restore locomotor activity (i.e., climbing capability, P < 0.05 by χ(2) test) of Drosophila melanogaster chronically exposed to paraquat compared to flies treated with paraquat alone in 1% glucose. We found that (10%) glucose partially prolongs life span and climbing in Drosophila exposed to iron, PQ or in combination, suggesting that both stimuli enhance a movement disorder in a concentration-dependent and temporal-related fashion. Moreover, chronic exposure of (1 mM) PQ/(0.5 mM) iron synergistically affect both survival and locomotor function independently of the temporal order of the exposure to the toxicants, but the survival is modulated in a concentration and temporal fashion by glucose. This investigation is the first to report that Ddc-GAL4 transgenic flies chronically fed with polyphenols increase life span (P < 0.05 by log-rang test) and enhance movement abilities (P < 0.05 by χ(2) test) compared to untreated Ddc-GAL4 or treated with paraquat in 1% glucose. Our present findings support the notion that Drosophila melanogaster might be a suitable model to study genetic, environmental and nutritional factors as causal and/or modulators in the development of PD. Most importantly, according to our model, we have demonstrated for the first time chronic polyphenols exposure as potential therapeutic compounds in the treatment of PD. These findings altogether open new avenues for the screening, testing and development of novel antioxidant drugs against oxidative stress stimuli.

Using paraquat to generate anion free radicals and hydrogen peroxide in in vitro: Antioxidant effect of vitamin E: A procedure to teach theoretical and experimental principles of reactive oxygen species biochemistry

The theoretical basis of reactive oxygen species and their impact on health issues are relatively easy to understand by biomedical students. The detection of reactive oxygen species requires expensive equipment, the procedures are time consuming and costly, and the results are hard to interpret. Moreover, cause-and-effect relationships in the living system are not so evident. In this report, we adapted a two-step procedure to detect anion superoxide radicals and hydrogen peroxide generation in lymphocytes exposed to paraquat by using nitroblue tetrazolium salt and dihydrorhodamine, respectively. Also, a two-step assay was performed to evaluate lymphocyte viability and nuclei morphologic changes on paraquat exposure for 1 and 24 hours incubation time by using trypan blue exclusion assay and acridine orange/ethidium bromide staining technique, respectively. Vitamin E was used as antioxidant to inhibit the deleterious effects of paraquat on cells. Students learned how to (i) design and perform experiments in the laboratory, (ii) read critical scientific literature, and (iii) discuss and contrast relevant information about reactive oxygen species as causative agents of cell death phenomenon.

Effects of insulin-like growth factor-1 on rotenone-induced apoptosis in human lymphocyte cells

Human peripheral blood lymphocytes have been useful as a putative model of oxidative stress-induced apoptosis for Parkinson's disease. The present work shows that rotenone, a mitochondrial complex I inhibitor, induced time- and concentration-dependent apoptosis in lymphocytes which was mediated by anion superoxide radicals (O(2)*(-))/hydrogen peroxide, depolarization of mitochondria, caspase-3 activation, concomitantly with the nuclear translocation of transcription factors such as NF-kappaB, p53, c-Jun and nuclei fragmentation. Since insulin-like growth factor-1 (IGF-1) interferes with a cell's apoptotic machinery when subjected to several stressful conditions, it is demonstrated here for the first time that IGF-1 effectively protects lymphocytes against rotenone through PI-3K/Akt activation, down-regulation of p53 and maintenance of mitochondrial membrane potential independently of ROS generation. These data might contribute to understanding the role played by IGF-1 against oxidative stress stimuli.

Paraquat and temperature affect nonspecific immune response of Colossoma macropomum

This study evaluated the effect of paraquat (PQ) and temperature on hematological parameters and nonspecific immune system of fish Colossoma macropomum (Cachama). Juveniles were used for all experiments. Fish were exposed to three temperatures (18, 28, 35°C) and 10mg/L PQ during 21 days (PQ LC(50) 96h was of 48.05mg/L). Hematological (Hb, Ht, VCM, HCM and CHCM and RBC) and immunological parameters (WBC, differential count of white cells, phagocytes, and bacterial killing by phagocytes) were analyzed for 7, 14 and 21 days. Fishes PQ exposed at 18°C decreased Hb, MCH and MCHC; we observed sickle erythrocytes in control group at 18°C, and in PQ-exposed groups at 18 and 35°C. Immunological parameters were not affected by temperature. Neutrophils decreased significantly in all PQ-exposed groups. Bacterial killing by phagocytes decreased in 18 and 35°C PQ-groups; a synergistic interaction was shown between PQ and temperature on WBC and lymphocytes. These results indicate that PQ affected neutrophils counts independently of temperature exposure; the temperature exerted a synergistic effect on PQ toxicity in lymphocyte counts and phagocytic response and besides nonspecific immune response, PQ and temperature affects hematological parameters such as Hb, MCH, MCHC and erythrocytes morphology.

The cannabinoid CP55,940 prolongs survival and improves locomotor activity in Drosophila melanogaster against paraquat: implications in Parkinson's disease

Cannabinoids have been shown to function as protective agents via receptor-independent and/or receptor-dependent mechanisms against stressful conditions. However, the neuroprotective mechanism of cannabinoids is far from conclusive. Therefore, the genuine antioxidant impact of cannabinoids in vivo is still uncertain. In this study, we demonstrate for the first time that CP55,940, a nonselective CB(1)/CB(2) cannabinoid receptor agonist, significantly protects and rescues Drosophila melanogaster against paraquat (PQ) toxicity via a receptor-independent mechanism. Interestingly, CP55,940 restores the negative geotaxis activity (i.e., climbing capability) of the fly exposed to PQ. Moreover, Drosophila fed with (1-200 microM) SP600125, a specific inhibitor of the stress responsive Jun-N-terminal kinase (JNK) signaling, and 20 mM PQ increased survival percentage and movement function (i.e., climbing capability) when compared to flies only treated with PQ. Taken together our results suggest that exogenous antioxidant cannabinoids can protect against and rescue from locomotor dysfunction in wild type (Canton-S) Drosophila exposed to stress stimuli. Therefore, cannabinoids may offer promising avenues for the design of molecules to prevent, delay, or ameliorate the treatment of population at high risk of suffering Parkinson disease.