Neuroprotective Effects of Thymol, a Dietary Monoterpene Against Dopaminergic Neurodegeneration in Rotenone-Induced Rat Model of Parkinson’s Disease

Parkinson’s disease (PD), a multifactorial movement disorder that involves progressive degeneration of the nigrostriatal system affecting the movement ability of the patient. Oxidative stress and neuroinflammation both are shown to be involved in the etiopathogenesis of PD. The aim of this study was to evaluate the therapeutic potential of thymol, a dietary monoterpene phenol in rotenone (ROT)-induced neurodegeneration in rats that precisely mimics PD in humans. Male Wistar rats were injected ROT at a dose of 2.5 mg/kg body weight for 4 weeks, to induce PD. Thymol was co-administered for 4 weeks at a dose of 50 mg/kg body weight, 30 min prior to ROT injection. The markers of dopaminergic neurodegeneration, oxidative stress and inflammation were estimated using biochemical assays, enzyme-linked immunosorbent assay, western blotting and immunocytochemistry. ROT challenge increased the oxidative stress markers, inflammatory enzymes and cytokines as well as caused significant damage to nigrostriatal dopaminergic system of the brain. Thymol treatment in ROT challenged rats appears to significantly attenuate dopaminergic neuronal loss, oxidative stress and inflammation. The present study showed protective effects of thymol in ROT-induced neurotoxicity and neurodegeneration mediated by preservation of endogenous antioxidant defense networks and attenuation of inflammatory mediators including cytokines and enzymes.

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Neuroprotective Effects of a GLP-2 Analogue in the MPTP Parkinson’s Disease Mouse Model

Journal of Parkinson s Disease ◽

10.3233/jpd-202318 ◽

2021 ◽

pp. 1-15

Author(s):

Zijuan Zhang ◽

Li Hao ◽

Ming Shi ◽

Ziyang Yu ◽

Simai Shao ◽

...

Keyword(s):

Parkinson’S Disease ◽

Parkinson's Disease ◽

Substantia Nigra ◽

Mouse Model ◽

Neurodegenerative Disorder ◽

Enzyme Linked Immunosorbent Assay ◽

Protective Effects ◽

Neuroprotective Effects ◽

Expression Levels ◽

Dual Agonist

Background: Glucagon-like peptide 2 (GLP-2) is a peptide hormone derived from the proglucagon gene expressed in the intestines, pancreas and brain. Some previous studies showed that GLP-2 improved aging and Alzheimer’s disease related memory impairments. Parkinson’s disease (PD) is a progressive neurodegenerative disorder, and to date, there is no particular medicine reversed PD symptoms effectively. Objective: The aim of this study was to evaluate neuroprotective effects of a GLP-2 analogue in the 1-Methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP) PD mouse model. Methods: In the present study, the protease resistant Gly(2)-GLP-2 (50 nmol/kg ip.) analogue has been tested for 14 days by behavioral assessment, transmission electron microscope, immunofluorescence histochemistry, enzyme-linked immunosorbent assay and western blot in an acute PD mouse model induced by MPTP. For comparison, the incretin receptor dual agonist DA5-CH was tested in a separate group. Results: The GLP-2 analogue treatment improved the locomotor and exploratory activity of mice, and improved bradykinesia and movement imbalance of mice. Gly(2)-GLP-2 treatment also protected dopaminergic neurons and restored tyrosine hydroxylase expression levels in the substantia nigra. Gly(2)-GLP-2 furthermore reduced the inflammation response as seen in lower microglia activation, and decreased NLRP3 and interleukin-1β pro-inflammatory cytokine expression levels. In addition, the GLP-2 analogue improved MPTP-induced mitochondrial dysfunction in the substantia nigra. The protective effects were comparable to those of the dual agonist DA5-CH. Conclusion: The present results demonstrate that Gly(2)-GLP-2 can attenuate NLRP3 inflammasome-mediated inflammation and mitochondrial damage in the substantia nigra induced by MPTP, and Gly(2)-GLP-2 shows neuroprotective effects in this PD animal model.

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Hesperetin protects SH-SY5Y cells against 6- hydroxydopamine-induced neurotoxicity via activation of NRF2/ARE signaling pathways

Tropical Journal of Pharmaceutical Research ◽

10.4314/tjpr.v19i6.12 ◽

2020 ◽

Vol 19 (6) ◽

pp. 1197-1201 ◽

Cited By ~ 1

Author(s):

Jing Li ◽

Yue Liu ◽

Li Wang ◽

Zhaowei Gu ◽

Zhigang Huan ◽

...

Keyword(s):

Oxidative Stress ◽

Parkinson’S Disease ◽

Parkinson's Disease ◽

Cell Viability ◽

Heme Oxygenase 1 ◽

Protective Effects ◽

Neuroprotective Effects ◽

Ldh Release ◽

6 Hydroxydopamine

Purpose: To investigation the protective effects of hesperetin against 6-hydroxydopamine (6-OHDA)- induced neurotoxicity. Methods: SH-SY5Y cells were incubated with 6-OHDA to create an in vitro model of neurotoxicity. This model was used to test the neuroprotective effects of hesperetin. Cell viability was assessed by MTT and lactate dehydrogenase (LDH) release assays. Flow cytometry and western blot were used to quantify apoptosis. Oxidative stress was evaluated by determining intracellular glutathione (GSH), malondialdehyde (MDA), superoxide dismutase (SOD), and reactive oxygen species (ROS). Results: In SH-SY5Y cells, treatment with 6-OHDA decreased cell viability and promoted LDH release. However, exogenous hesperetin protected against 6-OHDA-mediated toxicity. Similarly, although incubation with 6-OHDA induced apoptosis and increased cleaved caspase-3 and -9 levels, treatment with hesperetin protected against these effects. Treatment with 6-OHDA also led to significant oxidative stress, as indicated by reduced GSH and SOD levels and increased MDA and ROS levels in SH-SY5Y cells. However, these changes were reversed by pre-treatment with hesperetin. Of interest, hesperetin led to changes in 6-OHDA-induced expression of NRF2, heme oxygenase-1 (HO-1), glutamate-cysteine ligase (GCL) catalytic subunit (GCLC), and GCL modulatory (GCLM). Conclusion: Hesperetin protects against cell toxicity, apoptosis, and oxidative stress via activation of NRF2 pathway in a 6-OHDA-induced model of neurotoxicity. Future studies should investigate the use of hesperetin as a potential therapeutic approach for prevention or management of Parkinson’s disease. Keywords: Hesperetin, 6-OHDA, Neurotoxicity, NRF2, Parkinson’s disease

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α-Bisabolol, a Dietary Bioactive Phytochemical Attenuates Dopaminergic Neurodegeneration through Modulation of Oxidative Stress, Neuroinflammation and Apoptosis in Rotenone-Induced Rat Model of Parkinson’s Disease

Biomolecules ◽

10.3390/biom10101421 ◽

2020 ◽

Vol 10 (10) ◽

pp. 1421 ◽

Cited By ~ 1

Author(s):

Hayate Javed ◽

M. F. Nagoor Meeran ◽

Sheikh Azimullah ◽

Lujain Bader Eddin ◽

Vivek Dhar Dwivedi ◽

...

Keyword(s):

Oxidative Stress ◽

Parkinson’S Disease ◽

Parkinson's Disease ◽

Mitochondrial Dysfunction ◽

Proinflammatory Cytokines ◽

Rat Model ◽

Inflammatory Mediators ◽

Dopaminergic Neurons ◽

Neuroprotective Effects ◽

Dopaminergic Neurodegeneration

Rotenone (ROT), a plant-derived pesticide is a well-known environmental neurotoxin associated with causation of Parkinson’s disease (PD). ROT impairs mitochondrial dysfunction being mitochondrial complex-I (MC-1) inhibitor and perturbs antioxidant-oxidant balance that contributes to the onset and development of neuroinflammation and neurodegeneration in PD. Due to the scarcity of agents to prevent the disease or to cure or halt the progression of symptoms of PD, the focus is on exploring agents from naturally occurring dietary phytochemicals. Among numerous phytochemicals, α-Bisabolol (BSB), natural monocyclic sesquiterpene alcohol found in many ornamental flowers and edible plants garnered attention due to its potent pharmacological properties and therapeutic potential. Therefore, the present study investigated the neuroprotective effects of BSB in a rat model of ROT-induced dopaminergic neurodegeneration, a pathogenic feature of PD and underlying mechanism targeting oxidative stress, inflammation and apoptosis. BSB treatment significantly prevented ROT-induced loss of dopaminergic neurons and fibers in the substantia nigra and striatum respectively. BSB treatment also attenuated ROT-induced oxidative stress evidenced by inhibition of MDA formation and GSH depletion as well as improvement in antioxidant enzymes, SOD and catalase. BSB treatment also attenuated ROT-induced activation of the glial cells as well as the induction and release of proinflammatory cytokines (IL-1β, IL-6 and TNF-α) and inflammatory mediators (iNOS and COX-2) in the striatum. In addition to countering oxidative stress and inflammation, BSB also attenuated apoptosis of dopaminergic neurons by attenuating downregulation of anti-apoptotic protein Bcl-2 and upregulation of pro-apoptotic proteins Bax, cleaved caspases-3 and 9. Further, BSB was observed to attenuate mitochondrial dysfunction by inhibiting mitochondrial lipid peroxidation, cytochrome-C release and reinstates the levels/activity of ATP and MC-I. The findings of the study demonstrate that BSB treatment salvaged dopaminergic neurons, attenuated microglia and astrocyte activation, induction of inflammatory mediators, proinflammatory cytokines and reduced the expression of pro-apoptotic markers. The in vitro study on ABTS radical revealed the antioxidant potential of BSB. The results of the present study are clearly suggestive of the neuroprotective effects of BSB through antioxidant, anti-inflammatory and anti-apoptotic properties in ROT-induced model of PD.

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Protective Effects of an Ancient Chinese Kidney-Tonifying Formula against H2O2-Induced Oxidative Damage to MES23.5 Cells

Parkinson s Disease ◽

10.1155/2017/2879495 ◽

2017 ◽

Vol 2017 ◽

pp. 1-9

Author(s):

Yihui Xu ◽

Wei Lin ◽

Shuifen Ye ◽

Huajin Wang ◽

Tingting Wang ◽

...

Keyword(s):

Oxidative Stress ◽

Parkinson’S Disease ◽

Parkinson's Disease ◽

Oxidative Damage ◽

Cell Damage ◽

Critical Role ◽

Enzyme Linked Immunosorbent Assay ◽

Protective Effects ◽

Transmission Electron ◽

Potential Strategy

Oxidative damage plays a critical role in the etiology of neurodegenerative disorders including Parkinson’s disease (PD). In our study, an ancient Chinese kidney-tonifying formula, which consists ofCistanche,Epimedii,andPolygonatum cirrhifolium, was investigated to protect MES23.5 dopaminergic neurons against hydrogen peroxide- (H2O2-) induced oxidative damage. The damage effects of H2O2on MES23.5 cells and the protective effects of KTF against oxidative stress were evaluated using MTT assay, transmission electron microscopy (TEM), immunocytochemistry (ICC), enzyme-linked immunosorbent assay (ELISA), and immunoblotting. The results showed that cell viability was dramatically decreased after a 12 h exposure to 150 μM H2O2. TEM observation found that the H2O2-treated MES23.5 cells presented cellular organelle damage. However, when cells were incubated with KTF (3.125, 6.25, and 12.5 μg/ml) for 24 h after H2O2exposure, a significant protective effect against H2O2-induced damage was observed in MES23.5 cells. Using ICC, we found that KTF inhibited the reduction of the tyrosine hydroxylase (TH) induced by H2O2, upregulated the mRNA and protein expression of HO-1, CAT, and GPx-1, and downregulated the expression of caspase 3. These results indicated that KTF may provide neuron protection against H2O2-induced cell damage through ameliorating oxidative stress, and our findings provide a new potential strategy for the prevention and treatment of Parkinson’s disease.

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NRF2 Activation and Downstream Effects: Focus on Parkinson’s Disease and Brain Angiotensin

Antioxidants ◽

10.3390/antiox10111649 ◽

2021 ◽

Vol 10 (11) ◽

pp. 1649

Author(s):

Juan A. Parga ◽

Ana I. Rodriguez-Perez ◽

Maria Garcia-Garrote ◽

Jannette Rodriguez-Pallares ◽

Jose L. Labandeira-Garcia

Keyword(s):

Oxidative Stress ◽

Parkinson’S Disease ◽

Parkinson's Disease ◽

Transcription Factor ◽

Cellular Response ◽

Therapeutic Potential ◽

Special Focus ◽

Ros Production ◽

Neuroprotective Effects ◽

Downstream Effects

Reactive oxygen species (ROS) are signalling molecules used to regulate cellular metabolism and homeostasis. However, excessive ROS production causes oxidative stress, one of the main mechanisms associated with the origin and progression of neurodegenerative disorders such as Parkinson’s disease. NRF2 (Nuclear Factor-Erythroid 2 Like 2) is a transcription factor that orchestrates the cellular response to oxidative stress. The regulation of NRF2 signalling has been shown to be a promising strategy to modulate the progression of the neurodegeneration associated to Parkinson’s disease. The NRF2 pathway has been shown to be affected in patients with this disease, and activation of NRF2 has neuroprotective effects in preclinical models, demonstrating the therapeutic potential of this pathway. In this review, we highlight recent advances regarding the regulation of NRF2, including the effect of Angiotensin II as an endogenous signalling molecule able to regulate ROS production and oxidative stress in dopaminergic neurons. The genes regulated and the downstream effects of activation, with special focus on Kruppel Like Factor 9 (KLF9) transcription factor, provide clues about the mechanisms involved in the neurodegenerative process as well as future therapeutic approaches.

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Therapeutic effect of a histone demethylase inhibitor in Parkinson’s disease

Cell Death and Disease ◽

10.1038/s41419-020-03105-5 ◽

2020 ◽

Vol 11 (10) ◽

Cited By ~ 2

Author(s):

Ming-Dao Mu ◽

Zhong-Ming Qian ◽

Sheng-Xi Yang ◽

Kang-Lin Rong ◽

Wing-Ho Yung ◽

...

Keyword(s):

Oxidative Stress ◽

Parkinson’S Disease ◽

Parkinson's Disease ◽

Therapeutic Potential ◽

Histone Demethylase ◽

Epigenetic Mechanism ◽

Iron Chelators ◽

Cell Type Specificity ◽

Neuroprotective Effects ◽

Ferroportin 1

Abstract Iron accumulation in the substantia nigra is recognized as a hallmark of Parkinson’s disease (PD). Therefore, reducing accumulated iron and associated oxidative stress is considered a promising therapeutic strategy for PD. However, current iron chelators have poor membrane permeability and lack cell-type specificity. Here we identified GSK-J4, a histone demethylase inhibitor with the ability to cross blood brain barrier, as a potent iron suppressor. Only a trace amount of GSK-J4 significantly and selectively reduced intracellular labile iron in dopaminergic neurons, and suppressed H2O2 and 6-OHDA-induced cell death in vitro. The iron-suppressive effect was mainly mediated by inducing an increase in the expression of the iron exporter ferroportin-1. In parallel, GSK-J4 rescued dopaminergic neuron loss and motor defects in 6-OHDA-induced PD rats, which was accompanied by reduction of oxidative stress. Importantly, GSK-J4 rescued the abnormal changes of histone methylation, H3K4me3 and H3K27me3 during 6-OHDA treatment although the iron-suppressive and neuroprotective effects were sensitive to H3K4me3 inhibition only. Also, upregulating H3K4me3 increased ferroportin-1 expression and neuroprotection. Taken together, we demonstrate a previously unappreciated action of GSK-J4 on cell-specific iron suppression and neuroprotection via epigenetic mechanism. Compared with conventional iron chelators, this compound has a stronger therapeutic potential for PD.

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Blood Exosomes Have Neuroprotective Effects in a Mouse Model of Parkinson’s Disease

Oxidative Medicine and Cellular Longevity ◽

10.1155/2020/3807476 ◽

2020 ◽

Vol 2020 ◽

pp. 1-14

Author(s):

Ting Sun ◽

Zhe-Xu Ding ◽

Xin Luo ◽

Qing-Shan Liu ◽

Yong Cheng

Keyword(s):

Oxidative Stress ◽

Parkinson’S Disease ◽

Parkinson's Disease ◽

Amino Acid ◽

Dopaminergic Neurons ◽

Motor Coordination ◽

Oxidized Lipids ◽

Metabolomic Analysis ◽

Neuroprotective Effects ◽

And Control

Parkinson’s disease (PD) is a common and complex neurodegenerative disease; the pathogenesis of which is still uncertain. Exosomes, nanosized extracellular vesicles, have been suggested to participate in the pathogenesis of PD, but their role is unknown. Here, a metabolomic analysis of serum and brain exosomes showed differentially expressed metabolites between 1-Methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine hydrochloride- (MPTP-) induced PD mice and control mice, such as oxidized lipids, vitamins, and cholesterol. These metabolites were enriched in coenzyme, nicotinamide, and amino acid pathways related to PD, and they could be served as preclinical biomarkers. We further found that blood-derived exosomes from healthy volunteers alleviated impaired motor coordination in MPTP-treated mice. Results from immunohistochemistry and western blotting indicated that the loss of dopaminergic neurons in substantia nigra and striatum of PD model mice was rescued by the exosome treatment. The exosome treatment also restored the homeostasis of oxidative stress, neuroinflammation, and cell apoptosis in the model mice. These results suggest that exosomes are important mediators for PD pathogenesis, and exosomes are promising targets for the diagnosis and treatment of PD.

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Antioxidant Therapy in Parkinson’s Disease: Insights from Drosophila melanogaster

Antioxidants ◽

10.3390/antiox9010052 ◽

2020 ◽

Vol 9 (1) ◽

pp. 52 ◽

Cited By ~ 1

Author(s):

Federica De Lazzari ◽

Federica Sandrelli ◽

Alexander J. Whitworth ◽

Marco Bisaglia

Keyword(s):

Parkinson’S Disease ◽

Parkinson's Disease ◽

Drosophila Melanogaster ◽

Therapeutic Potential ◽

Experimental System ◽

Rapid Screening ◽

Antioxidant Compounds ◽

Oxygen Species ◽

Protective Effects ◽

High Concentrations

Reactive oxygen species (ROS) play an important role as endogenous mediators in several cellular signalling pathways. However, at high concentrations they can also exert deleterious effects by reacting with many macromolecules including DNA, proteins and lipids. The precise balance between ROS production and their removal via numerous enzymatic and nonenzymatic molecules is of fundamental importance for cell survival. Accordingly, many neurodegenerative disorders, including Parkinson’s disease (PD), are associated with excessive levels of ROS, which induce oxidative damage. With the aim of coping with the progression of PD, antioxidant compounds are currently receiving increasing attention as potential co-adjuvant molecules in the treatment of these diseases, and many studies have been performed to evaluate the purported protective effects of several antioxidant molecules. In the present review, we present and discuss the relevance of the use of Drosophila melanogaster as an animal model with which to evaluate the therapeutic potential of natural and synthetic antioxidants. The conservation of most of the PD-related genes between humans and D. melanogaster, along with the animal’s rapid life cycle and the versatility of genetic tools, makes fruit flies an ideal experimental system for rapid screening of antioxidant-based treatments.

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Comparison of the Protective Effects of Bee Venom Extracts with Varying PLA2 Compositions in a Mouse Model of Parkinson’s Disease

Toxins ◽

10.3390/toxins11060358 ◽

2019 ◽

Vol 11 (6) ◽

pp. 358 ◽

Cited By ~ 5

Author(s):

Kyung Hwa Kim ◽

Minhwan Kim ◽

Jaehwan Lee ◽

Hat Nim Jeon ◽

Se Hyun Kim ◽

...

Keyword(s):

Parkinson’S Disease ◽

Parkinson's Disease ◽

Mouse Model ◽

Therapeutic Potential ◽

Bee Venom ◽

Neuroprotective Activity ◽

Protective Effects ◽

Active Components ◽

Therapeutic Benefits ◽

Pharmacologically Active

Bee venom contains a number of pharmacologically active components, including enzymes and polypeptides such as phospholipase A2 (PLA2) and melittin, which have been shown to exhibit therapeutic benefits, mainly via attenuation of inflammation, neurotoxicity, and nociception. The individual components of bee venom may manifest distinct biological actions and therapeutic potential. In this study, the potential mechanisms of action of PLA2 and melittin, among different compounds purified from honey bee venom, were evaluated against Parkinson’s disease (PD). Notably, bee venom PLA2 (bvPLA2), but not melittin, exhibited neuroprotective activity against PD in a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) mouse model of PD. MPTP-induced behavioral deficits were also abolished after bvPLA2 treatment, depending on the PLA2 content. Further, bvPLA2 administration activated regulatory T cells (Tregs) while inhibiting inflammatory T helper (Th) 1 and Th17 cells in the MPTP mouse model of PD. These results indicate that bvPLA2, but not melittin, protected against MPTP and alleviated inflammation in PD. Thus, bvPLA2 is a promising and effective therapeutic agent in Parkinson’s disease.

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Neuroprotective Effects of Lindleyin on Hydrogen Peroxide-Induced Cell Injury and MPTP-Induced Parkinson’s Disease in C57BL/6 Mice

Evidence-based Complementary and Alternative Medicine ◽

10.1155/2020/2938432 ◽

2020 ◽

Vol 2020 ◽

pp. 1-10

Author(s):

Jin-Jie Zhang ◽

Xiao-Rong Shi ◽

Wen-Wen Lv ◽

Xiao-Long Zhou ◽

Ying-Dong Sun ◽

...

Keyword(s):

Oxidative Stress ◽

Parkinson’S Disease ◽

Hydrogen Peroxide ◽

Parkinson's Disease ◽

Cell Injury ◽

In Vivo Studies ◽

Antioxidant Enzyme Activities ◽

Apoptotic Pathway ◽

Neuroprotective Effects

Oxidative stress (OS) is a crucial factor influencing the development of Parkinson’s disease (PD). Here we first reported that Lindleyin (Lin), one of the major components of rhubarb, possessed neuroprotective effects against H2O2-induced SH-SY5Y cell injury and MPTP-induced PD of C57BL/6 mice. The results showed that Lin can decrease cell death and apoptotic rate induced by H2O2 through inhibiting mitochondrial apoptotic pathway and increasing the activities of SOD, GSH-Px, and CAT as well as decreasing the level of MDA. In addition, in vivo studies showed that oral administration of Lin (5 or 20 mg/kg) showed significant change in motor function deficits, antioxidant enzyme activities, apoptotic pathway, and tyrosine hydroxylase expression. Our results reveal that Lin might be a promising anti-PD agent by reducing OS and apoptosis.

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