Vanillin Attenuated Behavioural Impairments, Neurochemical Deficts, Oxidative Stress and Apoptosis Against Rotenone Induced Rat Model of Parkinson's Disease

A comprehensive pharmacology study reveals the molecular mechanisms underlying the antidepressant effects of Gastrodiae Rhizoma

BACKGROUND

Gastrodiae Rhizoma (GR) and its extract have been widely used in the treatment of depression, but the underlying mechanism of its antidepressant effects is unclear due to its numerous components.

PURPOSE

Revealing the cellular and molecular mechanisms underlying the antidepressant effects of GR through a comprehensive pharmacology-based in vivo and in vitro investigation.

METHODS

A mouse model of depression was established using chronic mild stress (CMS) procedure, and the antidepressant effects of GR were evaluated using systematic behavior. Metabolites in GR decoction and in mouse brain were identified by UPLC-QTOF-MS technology. Core components and targets of GR against MDD were screened based on network pharmacology analysis and molecular docking. The mechanism through which GR mitigated MDD was explored using transcriptome analysis, immunohistochemistry and western blotting in vitro and in vivo.

RESULTS

A total of 273 components were identified in the GR decoction, out of which 15 were detected in the brain of depressed mice treated with the GR decoction. We further identified nine key active ingredients, six essential targets, and fifth signaling pathways associated with the therapeutic effects of GR against MDD. We confirmed that the active ingredients of GR can target the neural stem/precursor cells (NSPCs) in the hippocampus of depressed mice to promote neurogenesis, as evidenced by a significant increase in the numbers of DCX+ cells, BrdU+ cells, BrdU+-DCX+ cells, and BrdU+-NeuN+ cells within the hippocampus of GR-treated mice compared to salinetreated mice under CMS exposure. Moreover, we have identified that the key active constituents of GR, namely gastrodin and parishin C, exert a targeted effect on EGFR to activate PI3K-Akt signaling in NSPCs, thereby facilitating proliferation and differentiation of NSPCs.

CONCLUSION

The antidepressant effect of GR involves the facilitation of PI3K/Akt-mediated neurogenesis through gastrodin and parishin C targeting EGFR in NSPCs.

"Methyl jasmonate: bridging plant defense mechanisms and human therapeutics"

A volatile organic substance produced from jasmonic acid, methyl jasmonate (MJ/MeJA), is an important plant hormone involved in stress responses and plant defense. Apart from its role in plants, MJ has garnered significant attention because of its pharmacological effects and possible therapeutic use in human health. This thorough analysis looks into the many biological actions of MJ, such as its antioxidant, anti-inflammatory, and anti-cancer effects. The underlying mechanism of these actions is examined, emphasizing MJ's ability to modulate important signaling pathways, cause cancer cells to undergo apoptosis, and boost immunological responses. Furthermore, MJ's capacity to manage long-term illnesses like cancer and neurological conditions like Parkinson's and Alzheimer's is examined. Preclinical and clinical research are beginning to provide evidence that MJ may be a useful medicinal drug. Nevertheless, more research is needed to fully understand its mode of action, enhance its administration methods, and evaluate its efficacy and safety in humans. This review highlights MJ's therapeutic promise and supports earlier research into its pharmacological capabilities and possible medical applications. This abstract highlights methyl jasmonate's pharmacological effects and therapeutic potential by providing a concise overview of the main topics covered in a thorough review.

Identification of key aroma compounds contributing to the pleasurable sensory experience of white Peony tea using GC-MS, computational modeling, and sensory evaluation

White Peony Tea (WPT) is valued for its unique flavor and pleasant sensory effects. However, the specific aroma compounds in WPT contributing to this pleasant sensation and the underlying mechanisms remain unclear. This study integrates GC-MS, computational modeling, and sensory evaluation to systematically explore the key pleasant aroma compounds in WPT and their potential mechanisms. Seven key components were identified as eliciting the pleasant sensation of WPT, including cedrol and β-ionone. These compounds activate human pleasure receptors, influencing neurological pathways to enhance sensory pleasure. Molecular simulations validated the stability of the interactions between the aroma compounds and their targets, specifically cedrol-CHRM4, cedrol-ADORA1, β-ionone-ADORA2A, and cedrol-MAOB. Sensory evaluation revealed pleasantness scores for these aroma compounds between 2.60 and 6.80, supporting the positive effects on sensory experience. This research provides scientific insight into the relationship between tea aroma and sensory pleasure, providing a foundation for the development of tea products.

Smoking, coffee intake, and Parkinson's disease: Potential protective mechanisms and components

Parkinson's disease (PD) is a common progressive neurodegenerative disease characterized by the loss of dopaminergic neurons in the substantia nigra pars compacta (SNpc). Environmental and lifestyle factors, such as smoking and coffee drinking, have been associated with a decreased risk for PD. However, the biological mechanisms underlying protective effects on PD are still not fully understood. It has been suggested that non-nicotine components in cigarette smoke and non-caffeine components in coffee may contribute to this protective effect. The aim of this review was to explore candidate molecules and mechanisms behind the effects of smoking and coffee drinking on PD by integrating findings from previous studies. By cross-referencing an index of tobacco constituents and a list of coffee constituents with existing literature on natural compounds and their structural analogs that show inhibitory activities against monoamine oxidase B, catechol O-methyltransferase, and α-synuclein fibrillation, we have identified tobacco and coffee components that inhibit these targets. Furthermore, tobacco and coffee components potentially play roles in suppressing neuroinflammation, activating the Nrf2 pathway as natural activators, and altering the gut microbiome. This review suggests that the phenolic compounds from tobacco and coffee investigated may contribute to the low incidence of PD in smokers and coffee drinkers, showing moderate to strong potential as therapeutic interventions. The current review suggests that multifunctional molecules found in coffee and cigarette smoke may have potential neuroprotective effects, but none of the data indicates that multifunctionality is required for these effects. This review will deepen our understanding of how smoking and coffee drinking are linked to a reduced risk of PD and will also be important in elucidating the mechanisms underlying the protective effects of smoking and coffee drinking on PD.

Epigallocatechin gallate mitigates the motor deficits in a rotenone-induced Parkinson's disease rat model via promoting protein kinase D1 and inhibiting neuronal Parthanatos

Parkinson's disease (PD), a neurodegenerative disorder characterized by degeneration of the dopaminergic (DA) neurons, is still lack of available treatments to completely block neurodegeneration. (-)-Epigallocatechin-3-gallate (EGCG), a predominant active polyphenol generated from green tea, exerts multiple neuroprotective roles in the nervous system. However, the function role of EGCG in PD and the underlying mechanism remains to be investigated. In the current study, we used the rotenone injection to build the PD rat model, followed by the EGCG treatment and determined by the behavior tests, measurements of malondialdehyde, glutathione, and superoxide dismutase levels, and enzyme-linked immunosorbent assay. We revealed that, in PD rats, EGCG upregulates protein kinase D1 (PKD1) and inhibits Parthanatos to ameliorate the impaired motor function, reduce the expression of tyrosine hydroxylase, suppress the oxidative stress, and suppress the inflammation in substantia nigra. These combined results suggest that EGCG can suppress oxidative stress and inflammation to prevent DA neuron degeneration to prevent rotenone-induced motor impairments, laying the foundation for EGCG to be a novel candidate for the treatment of PD.

Interaction of plant phenol vanillin with human hemoglobin: A spectroscopic and molecular docking study

Vanillin is a phenolic aldehyde widely used as a flavouring agent in the food industry. Vanillin has many health benefits and has gained attention in pharmacological industries also, due to its antioxidant properties and non-toxic nature. The interaction of vanillin with human hemoglobin (hHb), an abundant tetrameric heme protein, was investigated by several spectroscopic techniques and molecular modeling methods. UV-visible spectra showed that the binding of vanillin to hHb induces structural changes due to alterations in the micro-environment of hHb. Vanillin quenches the intrinsic fluorescence of hHb by the dynamic mechanism, which was confirmed by both temperature dependent and time resolved fluorescence studies. Vanillin binds spontaneously to hHb at a single site and the binding is stabilized by hydrogen bonds and hydrophobic interactions. The circular dichroism spectra showed that the binding of vanillin altered the secondary structure of hHb due to change in its alpha-helical content. Molecular docking identified the amino acids of hHb involved in binding to vanillin and also that the free energy change of the binding reaction is -5.5 kcal/mol. Thus, our results indicate that vanillin binds spontaneously to hHb at a single site and alters its secondary structure. This will help in understanding the potential use of vanillin and related antioxidants as therapeutic agents in various hematological disorders.

Molecular Insights on Coffee Components as Chemical Antioxidants

Coffee is not only a delicious beverage but also an important dietary source of natural antioxidants. We live in a world where it is impossible to avoid pollution, stress, food additives, radiation, and other sources of oxidants that eventually lead to severe health disorders. Fortunately, there are chemicals in our diet that counteract the hazards posed by the reactive species that trigger oxidative stress. They are usually referred to as antioxidants; some of them can be versatile compounds that exert such a role in many ways. This review summarizes, from a chemical point of view, the antioxidant effects of relevant molecules found in coffee. Their mechanisms of action, trends in activity, and the influence of media and pH in aqueous solutions, are analyzed. Structure-activity relationships are discussed, and the protective roles of these compounds are examined. A particular section is devoted to derivatives of some coffee components, and another one to their bioactivity. The data used in the analysis come from theoretical and computational protocols, which have been proven to be very useful in this context. Hopefully, the information provided here will pro-mote further investigations into the amazing chemistry contained in our morning coffee cup.   Resumen. El café no solo es una bebida deliciosa, sino también una importante fuente dietética de antioxidantes naturales. Vivimos en un mundo donde es imposible evitar la contaminación, el estrés, los aditivos alimentarios, la radiación y otras fuentes de oxidantes que eventualmente conducen a trastornos de salud graves. Afortunadamente, existen sustancias químicas en nuestra dieta que contrarrestan los peligros planteados por las especies reactivas que desencadenan el estrés oxidativo. Por lo general, se les denomina antioxidantes; algunos de ellos pueden ser compuestos versátiles que ejercen dicho papel de muchas maneras. Este artículo de revisión resume, desde un punto de vista químico, los efectos antioxidantes de moléculas relevantes encontradas en el café. Se analizan sus mecanismos de acción, tendencias en la actividad y la influencia del medio y el pH en soluciones acuosas. Se discuten las relaciones estructura-actividad, y se examinan los roles protectores de estos compuestos. Se dedica una sección particular a los derivados de algunos componentes del café, y otra a su bioactividad. Los datos utilizados en el análisis provienen de protocolos teóricos y computacionales, que han demostrado ser muy útiles en este contexto. Se espera que la información proporcionada aquí promueva investigaciones futuras sobre la química contenida en nuestra taza de café matutina.

Vanillin Mitigates the MPTP-Induced α-Synucleinopathy in a Mouse Model of Parkinson's Disease: Insights into the Involvement of Wnt/β-Catenin Signaling

BACKGROUND

The abnormal aggregation of α-synuclein (α-syn) in the substantia nigra pars compacta (SNpc) region of the brain is characteristic of Parkinson's disease (PD), leading to the selective demise of neurons. Modifications in the post-translational processing of α-syn, phosphorylation at Ser129 in particular, are implicated in α-syn aggregation and are considered key hallmarks of PD. Furthermore, dysregulated Wnt/β-catenin signaling, influenced by glycogen synthase kinase-3 beta (GSK-3β), is implicated in PD pathogenesis. Inhibition of GSK-3β holds promise in promoting neuroprotection by enhancing the Wnt/β-catenin pathway.

METHODS

In our previous study utilizing 1-methyl-4-phenylpyridinium (MPP+)-administered differentiated SH-SY5Y cells and a PD mouse model, we explored Vanillin's neuroprotective properties and related mechanisms against neuronal loss induced by MPP+/1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) administration. In the current study, we elucidated the mitigating effects of Vanillin on motor impairments, P-Ser129-α-syn expression, Wnt/β-catenin signaling, and autophagic neuron death induced by MPTP in a mouse model of PD by performing motor function tests, western blot analysis and immunostaining.

RESULTS

Our results show that Vanillin effectively modulated the motor dysfunctions, GSK-3β expression, and activity, activated the Wnt/β-catenin signaling, and reduced autophagic neuronal demise in the MPTP-lesioned mice, highlighting its neuroprotective effects.

CONCLUSIONS

These findings underscore the complex interplay between α-syn pathology, GSK-3β, Wnt/β-catenin signaling, and autophagic-cell death in PD pathogenesis. Targeting these pathways, particularly with Vanillin, can be a promising therapeutic strategy for restoring dopaminergic (DA-ergic) neuronal homeostasis and slowing the progression of PD. Further research is crucial to resolving existing disputes and translating these discoveries into effective therapeutic interventions for PD patients.

Ameliorative effects of vanillin against pentylenetetrazole-induced epilepsy and associated memory loss in mice: The role of Nrf2/HO-1/NQO1 and HMGB1/RAGE/TLR4/NFκB pathways

BACKGROUND

Epilepsy is a severe neurological disorder associated with substantial morbidity and mortality. Vanillin (Van) is a natural phenolic aldehyde with beneficial pharmacological properties. This study investigated the neuroprotective effects of Van in epilepsy and elucidated its mechanism of action.

METHODS

Swiss albino mice were divided into the following five groups: "normal group", 0.9 % saline; "pentylenetetrazole (PTZ) group", intraperitoneal administration of 35 mg/kg PTZ on alternate days up to 42 days; and "PTZ + Van 20", "PTZ + Van 40", and "PTZ + sodium valproate (Val)" groups received PTZ injections in conjunction withVan 20 mg, Van 40 mg/kg, and Val 300 mg/kg, respectively. Behavioural tests and hippocampal histopathological analysis were performed in all groups. The Nrf2/HO-1/NQO1 and HMGB1/RAGE/TLR4/NFκB pathways, oxidative stress, neuro-inflammation, and apoptotic markers were analysed. Furthermore, brain acetylcholinesterase (AChE) activity and levels of dopamine (DA), gamma-aminobutyric acid GABA, and serotonin 5-HT were assessed.

RESULTS

Van prolonged seizure manifestations and improved electroencephalogram (EEG)criteriain conjunction with 100 mg/kg PTZ once daily. Van administration increased Nrf2/HO-1/NQO1 levels, with subsequent attenuation of malondialdehyde (MDA) and nitric oxide (NO) levels with elevated glutathione (GSH) levels and intensified superoxide dismutase (SOD) and catalase activities. Van reduced the gene and protein expression of HMGB1/RAGE/TLR4/NFκB and decreased the levels of inflammatory and apoptotic markers. In addition, Van reduced AChE activity, and elevated glial fibrillary acidic proteins (GFAP) increased neurotransmitter and brain-derived neurotrophic factors (BDNF).

CONCLUSION

By increasing Nrf2/HO-1/NQO1 levels and downregulating the HMGB1/RAGE/TLR4/ NFκB pathway, Van offered protection in PTZ-kindled mice with subsequent attenuation in lipid peroxidation, upregulation in antioxidant enzyme activities, and reduction in inflammation and apoptosis.

Superoxide dismutase: a key target for the neuroprotective effects of curcumin

Over the past few years, the prevalence of neurodegenerative diseases (NDD) has increased dramatically. The community health system is burdened by the high healthcare costs associated with NDD. Superoxide dismutase (SOD) is a type of metalloenzyme that possesses a distinct characteristic of protecting the body from oxidative stress through antioxidants. In this way, SOD supplementation may activate the endogenous antioxidant mechanism in various pathological conditions and could be used to neutralize free radical excess. Several factors are responsible for damaging DNA and RNA in the body, including the overproduction of reactive species, particularly reactive oxygen species (ROS) and reactive nitrogen species (RNS). Excessive ROS/RNS have deleterious effects on mitochondria and their metabolic processes, mainly through increased mitochondrial proteins, lipids and DNA oxidation. Studies have shown that oxidative stress is implicated in the etiology of many diseases, including NDD. It is thought that anti-inflammatory compounds, particularly phytochemicals, can interfere with these pathways and regulate inflammation. Extensive experimental and clinical research has proven that curcumin (Cur) has anti-inflammatory and anti-neurologic properties. In this review, we have compiled the available data on Cur's anti-inflammatory properties, paying special attention to its therapeutic impact on NDD through SOD.

Association of serum individual and mixed aldehydes with depressive symptoms in the general population: A machine learning study

BACKGROUND

Humans have many opportunities to be exposed to aldehydes which have potential mechanisms for causing depression. We aimed to explore the relationships between serum individual and mixed aldehydes with depressive symptoms in general population.

METHODS

The data was extracted from the National Health and Nutrition Examination Survey 2013-2014. Depressive symptoms were assessed by Patient Health Questionnaire-9. Weighted binomial logistic regression and Bayesian kernel machine regression (BKMR) model were used to explore the association of six individual aldehyde and mixed aldehydes with depressive symptoms, respectively. Sex stratification analysis and sensitivity analysis were conducted.

RESULTS

A total of 701 participants were included. We found a positive association between the highest (Q4) versus lowest quartile (Q1) of butyraldehyde with depressive symptoms (OR: 2.86, 95 % CI: 1.22-6.68), and a negative association between the Q3 versus Q1 of benzaldehyde (0.21, 0.07-0.60) and isopentanaldehyde (0.28, 0.08-0.90) with depressive symptoms in multivariate-adjusted model. The mixed aldehydes were positively associated with depressive symptoms using BKMR model, and butyraldehyde and heptanaldehyde were the dominant aldehydes. Several aldehydes, such as butyraldehyde and benzaldehyde, interacted with each other in their effects on depressive symptoms. The results of gender stratification analysis showed that butyraldehyde was the major contributor to the total effect of aldehydes on depressive symptoms in males, while heptanaldehyde was the dominant aldehyde in females.

LIMITATIONS

Causality cannot be inferred in this cross-sectional study.

CONCLUSIONS

Our study indicated that mixed aldehydes can increase the risk of depressive symptoms, of which butyraldehyde and heptanaldehyde were the major contributing aldehydes.

Vanillin attenuates CdCl2-induced cytotoxicity in isolated human erythrocytes

Cadmium is a toxic heavy metal with no physiological role in the human body. Cadmium has high mobility due to its widespread industrial use, with no safe and effective therapeutic management. Cadmium toxicity manifests by increasing oxidative stress in target cells. We have explored the potential role of vanillin, a plant phenolic aldehyde and antioxidant, in mitigating cadmium chloride (CdCl2) induced hemotoxicity using isolated human erythrocytes. CdCl2 was added to erythrocytes, in the absence and presence of vanillin. Incubation of erythrocytes with CdCl2 alone inhibited methemoglobin reductase and enhanced methemoglobin level. Heme degradation and release of free iron (Fe2+), along with protein and membrane lipid oxidation, were also increased. A CdCl2-induced enhancement in reactive oxygen and nitrogen species was also seen, lowering the overall antioxidant power of cells. However, pre-incubation of erythrocytes with vanillin resulted in significant decreased generation of reactive species and prevented heme degradation and heme oxidation. Vanillin augmented the erythrocyte antioxidant capacity and reinstated the activities of major antioxidant, plasma membrane-bound and glucose metabolism enzymes. Scanning electron microscopy showed that CdCl2 treatment led to the formation of echinocytes which was prevented by vanillin. In all cases, no harmful effects of vanillin alone were seen. Thus, vanillin alleviates the toxicity of cadmium and can be potentially employed as a chemoprotectant against the damaging effects of this heavy metal.

Vanillin prevents the growth of endometriotic lesions through anti-inflammatory and antioxidant pathways in a mouse model

Endometriosis is an estrogen-dependent chronic inflammatory gynecological disease defined by the presence of endometrial glands and mesenchyme outside the uterine cavity, named ectopic endometrium. Recent studies showed that endometriosis is associated with hormone imbalance, inflammation and oxidative stress. As the main component of vanilla bean extract, vanillin is widely used as a flavoring agent in the food, pharmaceutical, and cosmetic industries. It is known for its anti-inflammatory, antibacterial, and antitumor properties, but its therapeutic efficacy in endometriosis has not been studied. In this study, we evaluated the roles of vanillin in this disease using an induced endometriotic mouse model. The results showed that vanillin significantly inhibited the growth of endometrial lesions. Compared with the control group, the weight and volume of lesions were reduced considerably in the vanillin-treated group, showing its fantastic ability to inhibit cell proliferation and promote apoptosis. In addition, in the treatment group, mRNA expression of the pro-inflammatory cytokines Tnfa, Infg, Il1b, and Il6 was reduced, the number of macrophages and neutrophils was decreased, and the NF-κB signaling pathway was inhibited, indicating that vanillin suppressed the inflammatory response in the ectopic endometrium. Besides, we found that the intensity of tissue reactive oxygen species (ROS) was significantly lower, and mitochondrial complex IV expression was reduced in the vanillin-treated group. Meanwhile, treatment of the immortalized human endometriotic epithelial cell line (11Z) with vanillin resulted in the downregulation of cyclin genes that drive the cell proliferation process, inhibited cell proliferation, promoted apoptosis, and downregulated the expression of LPS-induced inflammatory cytokines. Most importantly, our data showed that the vanillin treatment had only minimal effects on the eutopic endometrium with respect to the pregnancy process, indicating its safety to be used in treating endometriosis in adults. In conclusion, our data suggest that vanillin has potential therapeutic properties for endometriosis as a regulatory molecule of cell proliferation, apoptosis, inflammation, and oxidative stress.

Evaluation of Potential Neuroprotective Effects of Vanillin Against MPP+/MPTP-Induced Dysregulation of Dopaminergic Regulatory Mechanisms in SH-SY5Y Cells and a Mouse Model of Parkinson's Disease

Parkinson's disease (PD) is a progressive neurodegenerative condition. The pathogenesis of PD is still unknown, and drugs available for PD treatment either have side effects or have suboptimal efficacy. Flavonoids are potent antioxidants having little toxicity with extended use, suggesting they might hold promising therapeutic potential against PD. Vanillin (Van) is a phenolic compound that has exhibited neuroprotective properties in various neurological disorders, including PD. However, the neuroprotective role of Van in PD and its underlying mechanisms are scarce and therefore need more exploration. Here, we evaluated the neuroprotective potential of Van and its associated mechanisms against MPP⁺/MPTP-induced neuronal loss in differentiated human neuroblastoma (SH-SY5Y) cells and the mouse model of PD. In the present study, Van treatment significantly enhanced the cell viability and alleviated oxidative stress, mitochondrial membrane potential, and apoptosis in MPP⁺-intoxicated SH-SY5Y cells. Moreover, Van significantly ameliorated the MPP⁺-induced dysregulations in protein expression of tyrosine hydroxylase (TH) and mRNA expressions of GSK-3β, PARP1, p53, Bcl-2, Bax, and Caspase-3 genes in SH-SY5Y cells. Similar to our in vitro results, Van significantly alleviated MPTP-induced neurobehavioral dysregulations, oxidative stress, aberrant TH protein expressions, and immunoreactivity in SNpc of mice brains. Treatment of Van also prevented MPTP-mediated loss of TH-positive intrinsic dopaminergic neurons to SNpc and TH-fibers projecting to the striatum of mice. Thus, Van exhibited promising neuroprotective properties in the current study against MPP⁺/MPTP-intoxicated SH-SY5Y cells and mice, indicating its potential therapeutic properties against PD pathology.

Synthesis and virucide activity on zika virus of 1,2,3-triazole-containing vanillin derivatives

The Zika virus (ZIKV) is an arbovirus and belongs to the Flaviviridae family and Flavivirus genus, with dissemination in the Americas. In Brazil, the predominant strain is the Asian, promoting outbreaks that started in 2015 and are directly related to microcephaly in newborns and Guillain-Barré syndrome in adults. Recently, researchers identified a new African strain circulating in Brazil at the mid-end of 2018 and the beginning of 2019, with the potential to originate a new epidemic. To date, there is no approved vaccine or drug for the treatment of Zika syndrome, and the development of therapeutic alternatives to treat it is of relevance. A critical approach is to use natural products when searching for new chemical agents to treat Zika syndrome. The present investigation describes the preparation of a series of 1,2,3-triazoles derived from the natural product vanillin and the evaluation of their virucide activity. A series of fourteen derivatives were prepared via alkylation of vanillin followed by CuAAC (the copper(I)-catalyzed azide-alkyne cycloaddition) reaction. The compounds were fully characterized by infrared (I.R.), nuclear magnetic resonance (NMR), and high-resolution mass spectrometry (HRMS) techniques. The cytotoxicity of Vero cells and the effect on the Zika Virus of the vanillin derivatives were evaluated. It was found that the most effective compound corresponded to 4-((1-(4-isopropylbenzyl)-1H-1,2,3-triazol-4-yl)methoxy)-3-methoxybenzaldehyde (8) (EC₅₀ = 27.14 μM, IC₅₀ = 334.9 μM). Subsequent assessments, namely pre and post-treatment assays, internalization and adsorption inhibition assays, kinetic, electronic microscopy analyses, and zeta potential determination, revealed that compound 8 blocks the Zika virus infection in vitro by acting on the viral particle. A molecular docking study was performed, and the results are also discussed.

Barbigerone Potentially Alleviates Rotenone-Activated Parkinson's Disease in a Rodent Model by Reducing Oxidative Stress and Neuroinflammatory Cytokines

BACKGROUND

Parkinson's disease (PD) is a common age-related and slowly progressive neurodegenerative disease that affects approximately 1% of the elderly population. In recent years, phytocomponents have aroused considerable interest in the research for PD treatment as they provide a plethora of active compounds including antioxidant and anti-inflammatory compounds. Herein, we aimed to investigate the anti-Parkinson's effect of barbigerone, a natural pyranoisoflavone possessing antioxidant activity in a rotenone-induced rat model of PD.

METHODS

To evaluate antioxidant activity, a 0.5 mg/kg dose of rotenone was injected subcutaneously into rats. Barbigerone (10 and 20 mg/kg) was administered to rats for 28 days 1 h prior to rotenone. All behavioral parameters were assessed before sacrificing the rats. On the 29th day, all of the rats were humanely killed and assessed for biochemical changes in antioxidant enzymes (superoxide dismutase, glutathione, malondialdehyde, and catalase), neurotransmitter levels (dopamine, 5-hydroxyindoleacetic acid, serotonin, dihydroxyphenylacetic acid, and homovanillic acid levels), and neuroinflammatory cytokines [interleukin (IL)-1β, tumor necrosis factor-α, nuclear factor kappa B, and IL-6].

RESULTS

The data presented in this study has shown that barbigerone attenuated rotenone-induced motor deficits including the rotarod test, catalepsy, akinesia, and open-field test. Additionally, barbigerone has shown improvements in the biochemical and neuroinflammatory parameters in the rotenone-induced rat model of PD.

CONCLUSION

The results demonstrated that barbigerone exhibits antioxidant and anti-inflammatory actions via reducing oxidative stress and inflammatory cytokines. Altogether, these findings suggest that barbigerone could potentially be utilized as a therapeutic agent against PD.

Phytoestrogen β-Sitosterol Exhibits Potent In Vitro Antiviral Activity against Influenza A Viruses

Influenza is a contagious infection in humans that is caused frequently by low pathogenic seasonal influenza viruses and occasionally by pathogenic avian influenza viruses (AIV) of H5, H7, and H9 subtypes. Recently, the clinical sector in poultry and humans has been confronted with many challenges, including the limited number of antiviral drugs and the rapid evolution of drug-resistant variants. Herein, the anti-influenza activities of various plant-derived phytochemicals were investigated against highly pathogenic avian influenza A/H5N1 virus (HPAIV H5N1) and seasonal low pathogenic human influenza A/H1N1 virus (LPHIV H1N1). Out of the 22 tested phytochemicals, the steroid compounds β-sitosterol and β-sitosterol-O-glucoside have very potent activity against the predefined influenza A viruses (IAV). Both steroids could induce such activity by affecting multiple stages during IAV replication cycles, including viral adsorption and replication with a major and significant impact on the virus directly in a cell-free status "viricidal effect". On a molecular level, several molecular docking studies suggested that β-sitosterol and β-sitosterol-O-glucoside exhibited viricidal effects through blocking active binding sites of the hemagglutinin surface protein, as well as showing inhibitory effects against replication through the binding with influenza neuraminidase activity and blocking the active sites of the M2 proton channel activity. The phytoestrogen β-sitosterol has structural similarity with the active form of the female sex hormone estradiol, and this similarity is likely one of the molecular determinants that enables the phytoestrogen β-sitosterol and its derivative to control IAV infection in vitro. This promising anti-influenza activity of β-sitosterol and its O-glycoside derivative, according to both in vitro and cheminformatics studies, recommend both phytochemicals for further studies going through preclinical and clinical phases as efficient anti-influenza drug candidates.

Overview of the Role of Vanillin in Neurodegenerative Diseases and Neuropathophysiological Conditions

Nowadays, bioactive natural products play key roles in drug development due to their safety profile and strong antioxidant power. Vanillin is a natural phenolic compound found in several vanilla beans and widely used for food, cosmetic, and pharmaceutical products. Besides its industrial applications, vanillin possesses several beneficial effects for human health, such as antioxidant activity in addition to anti-inflammatory, anti-mutagenic, anti-metastatic, and anti-depressant properties. Moreover, vanillin exhibits neuroprotective effects on multiple neurological disorders and neuropathophysiological conditions. This study reviews the mechanisms of action by which vanillin prevents neuroinflammation and neurodegeneration in vitro and in vivo systems, in order to provide the latest views on the beneficial properties of this molecule in chronic neurodegenerative diseases and neuropathophysiological conditions.

Systemic Rotenone Administration Causes Extra-Nigral Alterations in C57BL/6 Mice

Systemic administration of rotenone replicates several pathogenic and behavioural features of Parkinson's disease (PD), some of which cannot be explained by deficits of the nigrostriatal pathway. In this study, we provide a comprehensive analysis of several neurochemical alterations triggered by systemic rotenone administration in the CNS of C57BL/6 mice. Mice injected with either 1, 3 or 10 mg/kg rotenone daily via intraperitoneal route for 21 days were assessed weekly for changes in locomotor and exploratory behaviour. Rotenone treatment caused significant locomotor and exploratory impairment at dosages of 3 or 10 mg/kg. Molecular analyses showed reductions of both TH and DAT expression in the midbrain, striatum and spinal cord, accompanied by altered expression of dopamine receptors and brain-derived neurotrophic factor (BDNF). Rotenone also triggered midbrain-restricted inflammatory responses with heightened expression of glial markers, which was not seen in extra-nigral regions. However, widespread alterations of mitochondrial function and increased signatures of oxidative stress were identified in both nigral and extra-nigral regions, along with disruptions of neuroprotective peptides, such as pituitary adenylate cyclase-activating polypeptide (PACAP), vasoactive intestinal peptide (VIP) and activity-dependent neuroprotective protein (ADNP). Altogether, this study shows that systemic rotenone intoxication, similarly to PD, causes a series of neurochemical alterations that extend at multiple CNS levels, reinforcing the suitability of this pre-clinical model for the study extra-nigral defects of PD.

The effects of bioactive components from the rhizome of gastrodia elata blume (Tianma) on the characteristics of Parkinson's disease

Parkinson's disease (PD) is an age-related chronic neurodegenerative disease caused by the death and degeneration of dopaminergic neurons in the substantia nigra of the midbrain. The decrease of the neurotransmitter dopamine in the patient's brain leads to various motor symptoms. PD drugs mainly enhance dopamine levels but cannot prevent or slow down the loss of dopaminergic neurons. In addition, they exhibit significant side effects and addiction issues during long-term use. Therefore, it is particularly urgent to develop novel drugs that have fewer side effects, can improve PD symptoms, and prevent the death of dopaminergic neurons. The rhizome of Gastrodia elata Blume (Tianma) is a well-known medicinal herb and has long been used as a treatment of nervous system-related diseases in China. Several clinical studies showed that formula comprising Tianma could be used as an add-on therapy for PD patients. Pharmacological studies indicated that Tianma and its bioactive components can reduce the death of dopaminergic neurons, α-synuclein accumulation, and neuroinflammation in various PD models. In this review, we briefly summarize studies regarding the effects of Tianma and its bioactive components' effects on major PD features and explore the potential use of Tianma components for the treatment of PD.

From kitchen to clinic: Pharmacotherapeutic potential of common spices in Indian cooking in age-related neurological disorders

Aging is described as an advanced time-related collection of changes that may negatively affect with the risk of several diseases or death. Aging is a main factor of several age-related neurological disorders, including neurodegenerative diseases (Alzheimer’s disease, Parkinson’s disease, and dementia), stroke, neuroinflammation, neurotoxicity, brain tumors, oxidative stress, and reactive oxygen species (ROS). Currently available medications for age-related neurological disorders may lead to several side effects, such as headache, diarrhea, nausea, gastrointestinal (GI) diseases, dyskinesia, and hallucinosis. These days, studies on plant efficacy in traditional medicine are being conducted because herbal medicine is affordable, safe, and culturally acceptable and easily accessible. The Indian traditional medicine system called Ayurveda uses several herbs and medicinal plants to treat various disorders including neurological disorders. This review aims to summarize the data on the neuroprotective potential of the following common Indian spices widely used in Ayurveda: cumin (Cuminum cyminum (L.), Apiaceae), black cumin (Nigella sativa (L.), Ranunculaceae), black pepper (Piper nigrum (L.), Piperaceae), curry leaf tree (Murraya koenigii (L.), Spreng Rutaceae), fenugreek (Trigonella foenum-graecum (L.), Fabaceae), fennel (Foeniculum vulgare Mill, Apiaceae), cardamom (Elettaria cardamomum (L.) Maton, Zingiberaceae), cloves (Syzygium aromaticum (L.) Merr. & L.M.Perry, Myrtaceae), and coriander (Coriandrum sativum (L.), Apiaceae) in age-related neurological disorders.

Ameliorative effect of vanillin on scopolamine-induced dementia-like cognitive impairment in a mouse model

BACKGROUND

Alzheimer's disease (AD) is the most common form of dementia, which is among the top five causes of death in the United States. It is a neurodegenerative disorder that causes permanent loss of memory and cognition. The current pharmacotherapy for AD is based on providing symptomatic relief only and has many side effects. There is a need for a safer, disease-modifying drug for the treatment of AD.

EXPERIMENTAL APPROACH

The PASS online software was used to screen phytoconstituents based on their predicted effects on various AD-related targets. Vanillin was selected as the compound of interest, as it has not been researched elaborately on any animal model of AD. The acetylcholinesterase inhibitory activity of vanillin was established in vitro. Thereafter, ameliorative effect of vanillin was evaluated using the exteroceptive memory model in scopolamine-induced cognitive impairment mice model.

RESULTS

Vanillin showed an acetylcholinesterase inhibitory activity in vitro, and the IC50 value was calculated to be 0.033 mM. Vanillin significantly reversed the memory and behavioral deficits caused by scopolamine as demonstrated by significant improvement in memory in negative reinforcement, elevated plus maze, and spatial learning paradigms. Vanillin also proved to have a nootropic effect. Also, vanillin proved to have significantly better antioxidant and acetylcholinesterase inhibitory effects in vivo than donepezil hydrochloride. The potential anti-AD activity of vanillin was also confirmed by the reduction in IL-6 levels and TNF-α levels.

CONCLUSION

Our results suggest that vanillin is a safe and effective natural drug candidate having a great potential for the treatment of AD. However, more research is required to evaluate its effect on A beta plaques and Tau neurofibrillary tangles in vivo.

Nutritional and Phyto-Therapeutic Value of the Halophyte Cladium mariscus L. (Pohl.): A Special Focus on Seeds

This work searched for the phyto-therapeutic potential and nutritional value of seeds from the halophyte Cladium mariscus L. (Pohl.), aiming at its use as a source of bioactive ingredients for the food industry. Hence, the nutritional profile, including minerals, of seeds biomass was determined; food-grade samples were prepared, and their phytochemical fingerprinting assessed. Extracts were evaluated for in vitro antioxidant potential, inhibitory capacity towards enzymes related to neuroprotection, diabetes, and hyperpigmentation, and anti-inflammatory properties, along with a toxicological assessment. Sawgrass seeds can be considered a proper nutritional source with a good supply of minerals. All extracts had a high level of total phenolics (65.3−394.4 mg GAE/g DW) and showed a chemically rich and diverse profile of metabolites that have several biological properties described (e.g., antioxidant, anti-inflammatory). Extracts had no significant toxicity (cell viabilities > 80%) and were overall strong antioxidants (particularly at radical scavenging and reducing iron), effective tyrosinase inhibitors (55−71 mg KAE/g DW), showed anti-inflammatory properties (30−60% NO decrease), and had moderate capacity to inhibit enzymes related to neuroprotection (AChE 3.7−4.2, BChE 4.3−6.0 mg GALE/g DW) and diabetes (α-glucosidase 1.0−1.1, α-amylase 0.8−1.1 mmol ACAE/g). Altogether, results suggest that sawgrass seeds have the potential to be exploited as a new food product and are a reservoir of bioactive molecules with prospective applications as ingredients for value-added, functional, and/or preservative food products.

Europinidin Inhibits Rotenone-Activated Parkinson's Disease in Rodents by Decreasing Lipid Peroxidation and Inflammatory Cytokines Pathways

Background: Europinidin is a derivative of delphinidin obtained from the plants Plumbago Europea and Ceratostigma plumbaginoides. This herb has wide medicinal applications in treating various diseases but there are very few studies available on this bioactive compound. Considering this background, the present study is designed for the evaluation of Europinidin against Parkinson’s disease. Aim: The investigation aims to assess the effect of Europinidin in the rotenone-activated Parkinson’s paradigm. Methods: To evaluate neuroprotective activity, rotenone (1.5 mg/kg s.c) and europinidin (10 mg/kg and 20 mg/kg) was administered in rats for 21 days. The behavioural parameters were performed before sacrificing the rats. On the 22nd day, all the rats were assessed for biochemical markers (SOD, GSH, MDA, Catalase), neurotransmitter levels (Dopamine, 5-HIAA, DOPAC, and HVA levels), and neuroinflammatory markers (IL-6, IL-1β and TNF-α). Results: It was found that rotenone produced significant (p < 0.001) oxidative damage, a cholinergic deficit, dopaminergic loss, and a rise in neuroinflammatory markers in rats. Conclusion: The study concludes that europinidin possesses anti-oxidant and anti-inflammatory properties. The results suggest the therapeutic role of europinidin against rotenone-activated behavioural, biochemical, and neuroinflammatory alterations in rats.

Biologically Active Compounds Present in Tobacco Smoke: Potential Interactions Between Smoking and Mental Health

Tobacco dependence remains one of the major preventable causes of premature morbidity and mortality worldwide. There are well over 8,000 compounds present in tobacco and tobacco smoke, but we do not know what effect, if any, many of them have on smokers. Major interest has been on nicotine, as well as on toxic and carcinogenic effects and several major and minor components of tobacco smoke responsible for the negative health effects of smoking have been elucidated. Smokers themselves report a variety of positive effects from smoking, including effects on depression, anxiety and mental acuity. Smoking has also been shown to have protective effects in Parkinson’s Disease. Are the subjective reports of a positive effect of smoking due to nicotine, of some other components of tobacco smoke, or are they a manifestation of the relief from nicotine withdrawal symptoms that smoking provides? This mini-review summarises what is currently known about the components of tobacco smoke with potential to have positive effects on smokers.

Neuroprotective effects of catechin and quercetin in experimental Parkinsonism through modulation of dopamine metabolism and expression of IL-1β, TNF-α, NF-κB, IκKB, and p53 genes in male Wistar rats

The neurobehavioral, brain redox-stabilizing and neurochemical modulatory properties of catechin and quercetin in rotenone-induced Parkinsonism, and the involvement of NF-κB-mediated inflammation, were investigated. Male Wistar rats subcutaneously administered with multiple doses of 1.5mg/kg rotenone were post-treated with 5-20mg/kg catechin or quercetin. This was followed by neurobehavioral evaluation, biochemical estimations, and assessment of neurotransmitter metabolism in the striatum. Expression of genes involved in the canonical pathway for the activation of NF-κB mediated inflammation (IL-1β, TNF-α, NF-κB, and IκKB) and the pro-apoptotic gene, p53, in the striatum was determined by RT-qPCR. Catechin and quercetin mitigated neurobehavioral deficits caused by rotenone. Both flavonoids attenuated striatal redox stress and neurochemical dysfunction, optimized disturbed dopamine metabolism, and improved depletion of neuron density caused by rotenone toxicity. While administration of catechin produced a more pronounced attenuating effect on IL-1β, TNF-α, and p53 genes, the attenuating effect of quercetin (20mg/kg) was more pronounced on NF-κB and IκKB gene expressions when compared to the group administered with rotenone only. Comparatively, quercetin demonstrated superior protection against rotenone neurotoxicity. It is concluded that catechin and quercetin have potential relevance in Parkinson's disease therapy through amelioration of redox stress, optimization of dopamine metabolism, and modulation of anti-inflammatory and anti-apoptotic pathways.

Vanillin attenuates proinflammatory factors in a tMCAO mouse model via inhibition of TLR4/NF-kB signaling pathway

Vanillin has been reported to reduce hippocampal neuronal death in rat models of global cerebral ischemia. However, the immunoregulatory mechanism of vanillin in ischemic stroke is still unclear. To investigate the role of vanillin in a mouse model of ischemic stroke, we administered vanillin to mice after transient middle cerebral artery occlusion (tMCAO) by tail vein injection. Vanillin reduced infarct volume and improved motor function in mice after ischemia and reperfusion. IL-1β and TNF-α were decreased in ischemic brain tissue of tMCAO mice after vanillin treatment compared with saline treatment. Similar effects were observed using the in vitro LPS-stimulated microglia cell model. Moreover, the reduced expression of proinflammatory cytokines in the vanillin group was related to TLR4/NF-κB signaling. Taken together, the findings suggest that vanillin decreased microglial activation by inhibiting the TLR4 /NF-κB signaling pathway, which reduced expression of proinflammatory cytokines IL-1β and TNF-α, and finally reduced the infarct volume and improved motor function in tMCAO mice.

The anxiolytic Drug Buspirone Prevents Rotenone-Induced Toxicity in a Mouse Model of Parkinson’s Disease

A pharmacological and genetic blockade of the dopamine D3 receptor (D3R) has shown to be neuroprotective in models of Parkinson’s disease (PD). The anxiolytic drug buspirone, a serotonin receptor 1A agonist, also functions as a potent D3R antagonist. To test if buspirone elicited neuroprotective activities, C57BL/6 mice were subjected to rotenone treatment (10mg/kg i.p for 21 days) to induce PD-like pathology and were co-treated with increasing dosages of buspirone (1, 3, or 10 mg/kg i.p.) to determine if the drug could prevent rotenone-induced damage to the central nervous system (CNS). We found that high dosages of buspirone prevented the behavioural deficits caused by rotenone in the open field test. Molecular and histological analyses confirmed that 10 mg/kg of buspirone prevented the degeneration of TH-positive neurons. Buspirone attenuated the induction of interleukin-1β and interleukin-6 expression by rotenone, and this was paralleled by the upregulation of arginase-1, brain-derived neurotrophic factor (BDNF), and activity-dependent neuroprotective protein (ADNP) in the midbrain, striatum, prefrontal cortex, amygdala, and hippocampus. Buspirone treatment also improved mitochondrial function and antioxidant activities. Lastly, the drug prevented the disruptions in the expression of two neuroprotective peptides, pituitary adenylate cyclase-activating polypeptide (PACAP) and vasoactive intestinal peptide (VIP). These results pinpoint the neuroprotective efficacy of buspirone against rotenone toxicity, suggesting its potential use as a therapeutic agent in neurodegenerative and neuroinflammatory diseases, such as PD.

E-liquids and vanillin flavoring disrupts retinoic acid signaling and causes craniofacial defects in Xenopus embryos

Environmental teratogens such as smoking are known risk factors for developmental disorders such as cleft palate. While smoking rates have declined, a new type of smoking, called vaping is on the rise. Vaping is the use of e-cigarettes to vaporize and inhale an e-liquid containing nicotine and food-like flavors. There is the potential that, like smoking, vaping could also pose a danger to the developing human. Rather than waiting for epidemiological and mammalian studies, we have turned to an aquatic developmental model, Xenopus laevis, to more quickly assess whether e-liquids contain teratogens that could lead to craniofacial malformations. Xenopus, like zebrafish, has the benefit of being a well-established developmental model and has also been effective in predicting whether a chemical could be a teratogen. We have determined that embryonic exposure to dessert flavored e-liquids can cause craniofacial abnormalities, including an orofacial cleft in Xenopus. To better understand the underlying mechanisms contributing to these defects, transcriptomic analysis of the facial tissues of embryos exposed to a representative dessert flavored e-liquid vapor extract was performed. Analysis of differentially expressed genes in these embryos revealed several genes associated with retinoic acid metabolism or the signaling pathway. Consistently, retinoic acid receptor inhibition phenocopied the craniofacial defects as those embryos exposed to the vapor extract of the e-liquid. Such malformations also correlated with a group of common differentially expressed genes, two of which are associated with midface birth defects in humans. Further, e-liquid exposure sensitized embryos to forming craniofacial malformations when they already had depressed retinoic acid signaling. Moreover, 13-cis-retinoic acid treatment could significantly reduce the e-liquid induced malformation in the midface. Such results suggest the possibility of an interaction between retinoic acid signaling and e-liquid exposure. One of the most popular and concentrated flavoring chemicals in dessert flavored e-liquids is vanillin. Xenopus embryos exposed to this chemical closely resembled embryos exposed to dessert-like e-liquids and a retinoic acid receptor antagonist. In summary, we determined that e-liquid chemicals, in particular vanillin, can cause craniofacial defects potentially by dysregulating retinoic acid signaling. This work warrants the evaluation of vanillin and other such flavoring additives in e-liquids on mammalian development.

Methyl Jasmonate: Behavioral and Molecular Implications in Neurological Disorders

Methyl jasmonate (MJ) is a derivative of the jasmonate family which is found in most tropical regions of the world and present in many fruits and vegetables such as grapevines, tomato, rice, and sugarcane. MJ is a cyclopentanone phytohormone that plays a vital role in defense against stress and pathogens in plants. This has led to its isolation from plants for studies in animals. Many of these studies have been carried out to evaluate its therapeutic effects on behavioral and neurochemical functions. It has however been proposed to have beneficial potential over a wide range of neurological disorders. Hence, this review aims to provide an overview of the neuroprotective properties of MJ and its probable mechanisms of ameliorating neurological disorders. The information used for this review was sourced from research articles and scientific databases using 'methyl jasmonate', 'behavior', 'neuroprotection', 'neurodegenerative diseases', and 'mechanisms' as search words. The review highlights its influences on behavioral patterns of anxiety, aggression, depression, memory, psychotic, and stress. The molecular mechanisms such as modulation of the antioxidant defense, inflammatory biomarkers, neurotransmitter regulation, and neuronal regeneration, underlying its actions in managing neurodegenerative diseases like Alzheimer's and Parkinson's diseases are also discussed. This review, therefore, provides a detailed evaluation of methyl jasmonate as a potential neuroprotective compound with the ability to modify behavioral and molecular biomarkers underlying neurological disorders. Hence, MJ could be modeled as a guided treatment for the management of brain diseases.

Natural Phytochemicals as Novel Therapeutic Strategies to Prevent and Treat Parkinson's Disease: Current Knowledge and Future Perspectives

Parkinson's disease (PD) is the second-most common neurodegenerative chronic disease affecting both cognitive performance and motor functions in aged people. Yet despite the prevalence of this disease, the current therapeutic options for the management of PD can only alleviate motor symptoms. Research has explored novel substances for naturally derived antioxidant phytochemicals with potential therapeutic benefits for PD patients through their neuroprotective mechanism, targeting oxidative stress, neuroinflammation, abnormal protein accumulation, mitochondrial dysfunction, endoplasmic reticulum stress, neurotrophic factor deficit, and apoptosis. The aim of the present study is to perform a comprehensive evaluation of naturally derived antioxidant phytochemicals with neuroprotective or therapeutic activities in PD, focusing on their neuropharmacological mechanisms, including modulation of antioxidant and anti-inflammatory activity, growth factor induction, neurotransmitter activity, direct regulation of mitochondrial apoptotic machinery, prevention of protein aggregation via modulation of protein folding, modification of cell signaling pathways, enhanced systemic immunity, autophagy, and proteasome activity. In addition, we provide data showing the relationship between nuclear factor E2-related factor 2 (Nrf2) and PD is supported by studies demonstrating that antiparkinsonian phytochemicals can activate the Nrf2/antioxidant response element (ARE) signaling pathway and Nrf2-dependent protein expression, preventing cellular oxidative damage and PD. Furthermore, we explore several experimental models that evaluated the potential neuroprotective efficacy of antioxidant phytochemical derivatives for their inhibitory effects on oxidative stress and neuroinflammation in the brain. Finally, we highlight recent developments in the nanodelivery of antioxidant phytochemicals and its neuroprotective application against pathological conditions associated with oxidative stress. In conclusion, naturally derived antioxidant phytochemicals can be considered as future pharmaceutical drug candidates to potentially alleviate symptoms or slow the progression of PD. However, further well-designed clinical studies are required to evaluate the protective and therapeutic benefits of phytochemicals as promising drugs in the management of PD.

A Review of Plant Extracts and Plant-Derived Natural Compounds in the Prevention/Treatment of Neonatal Hypoxic-Ischemic Brain Injury

Neonatal hypoxic-ischemic (HI) brain injury is one of the major drawbacks of mortality and causes significant short/long-term neurological dysfunction in newborn infants worldwide. To date, due to multifunctional complex mechanisms of brain injury, there is no well-established effective strategy to completely provide neuroprotection. Although therapeutic hypothermia is the proven treatment for hypoxic-ischemic encephalopathy (HIE), it does not completely chang outcomes in severe forms of HIE. Therefore, there is a critical need for reviewing the effective therapeutic strategies to explore the protective agents and methods. In recent years, it is widely believed that there are neuroprotective possibilities of natural compounds extracted from plants against HIE. These natural agents with the anti-inflammatory, anti-oxidative, anti-apoptotic, and neurofunctional regulatory properties exhibit preventive or therapeutic effects against experimental neonatal HI brain damage. In this study, it was aimed to review the literature in scientific databases that investigate the neuroprotective effects of plant extracts/plant-derived compounds in experimental animal models of neonatal HI brain damage and their possible underlying molecular mechanisms of action.

Neuroprotective Effects of Higenamine Against the Alzheimer's Disease Via Amelioration of Cognitive Impairment, A Burden, Apoptosis and Regulation of Akt/GSK3β Signaling Pathway

The present investigation was envisaged to elucidate the neuroprotective effect of Higenamine (HGN) against aluminum chloride (AlCl₃) triggered experimental Alzheimer's disease (AD) rat model. Thirty-six male albino Wister rats were randomized and divided in 6 groups and subjected to experimentation for 6 weeks. Control group, AlCl₃ (100 mg/kg orally), HGN (50 mg/kg orally), HGN25, HGN50, HGN75 (HGN 25, 50 and 75 mg/kg respectively and AlCl₃ 100 mg/kg orally). After completion of 42 days protocol, the animals were subjected to passive avoidance test. The animals were then anesthetized by intramuscularly injecting ketamine hydrochloride (24 mg/kg body weight) and euthanized by cervical amputation. Cortical and hippocampal tissues were carefully removed and were employed for quantification of aluminum and acetylcholinesterase. The tissues were quantified using Western blotting and detection kits for APP, Aβ_1-42, β and γ secretases, Bax, Bad, caspases-9, cyto-c, pAkt and pGSK-3β, and oxidative markers. HGN significantly protected AlCl₃ induced memory and learning impairments, Al overload, AChE hyperactivity, amyloid β (Aβ) burden and apoptosis in brain tissues via activating Akt/GSK3β pathway. HGN attenuated oxidative damage induced by Al by modulation of oxidative markers. Our findings advocate the neuroprotective effect of HGN in AlCl₃ induced AD rat model.

Isolongifolene mitigates rotenone-induced dopamine depletion and motor deficits through anti-oxidative and anti-apoptotic effects in a rat model of Parkinson's disease

Isolongifolene (ILF), a novel tricyclic sesquiterpene compound isolated from the Indian herb Murraya koenigii (M. koenigii), has been previously demonstrated to have a neuroprotective effect against rotenone-induced oxidative stress, mitochondrial dysfunction, and apoptosis in in vitro model. However, these neuroprotective and anti-apoptotic effects of ILF are not well understood and must be further investigated to elucidate the underlying molecular mechanism of ILF in animal experiments. The objective of this study was to evaluate the neuroprotective effect of ILF on motor impediments, neurochemical variables, anti-oxidative indices, and apoptotic protein expression in a rotenone-induced rat model of Parkinson's disease (PD). PD was induced in male albino Wistar rats via injection of 2.5 mg/kg rotenone for 4 weeks. Rotenone produces PD-like effects by promoting mitochondrial complex I inhibition and microglial activation properties. The protective effect of three different doses of ILF 5, 10 and 20 mg/kg were evaluated for spontaneous locomotion, rotarod performance, and striatal dopamine (DA) content. The results showed that ILF dose-dependently ameliorated the rotenone-induced striatal DA loss and motor impairment from 10 mg/kg. Therefore, we selected 10 mg/kg as the ILF dose for further investigation. Chronic administration of rotenone caused PD-related pathological processes like oxidative stress, and produced a significant decrease in tyrosine hydroxylase (TH), DA transporter (DAT), Vesicular monoamine transporter 2 (VMAT2), and a significant upregulated in α-synuclein and apoptotic protein expression of Bax, Cyt-C and caspases -3, -8 and -9 as well as by decreasing Bcl2 expression. Treatment with ILF 10 mg/kg mitigated oxidative stress in rotenone-treated rats. Furthermore, ILF dramatically alleviated rotenone-induced toxicity and cell death by increasing TH, DAT and VMAT2 expression and reducing the upregulation of α-synuclein, Bax, Cyt-C, caspases -3, -8 and -9. Together, our results confirm that ILF's protective effect against rotenone-induced PD is mediated through anti-oxidant and anti-apoptotic properties. However, further in-depth investigations on ILF's anti-inflammatory and mitochondrial protective abilities are needed to establish ILF as a potential drug candidate for the treatment of Parkinson's disease.

Behavioral Tests in Neurotoxin-Induced Animal Models of Parkinson's Disease

Currently, neurodegenerative diseases are a major cause of disability around the world. Parkinson's disease (PD) is the second-leading cause of neurodegenerative disorder after Alzheimer's disease. In PD, continuous loss of dopaminergic neurons in the substantia nigra causes dopamine depletion in the striatum, promotes the primary motor symptoms of resting tremor, bradykinesia, muscle rigidity, and postural instability. The risk factors of PD comprise environmental toxins, drugs, pesticides, brain microtrauma, focal cerebrovascular injury, aging, and hereditary defects. The pathologic features of PD include impaired protein homeostasis, mitochondrial dysfunction, nitric oxide, and neuroinflammation, but the interaction of these factors contributing to PD is not fully understood. In neurotoxin-induced PD models, neurotoxins, for instance, 6-hydroxydopamine (6-OHDA), 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), 1-Methyl-4-phenylpyridinium (MPP+), paraquat, rotenone, and permethrin mainly impair the mitochondrial respiratory chain, activate microglia, and generate reactive oxygen species to induce autooxidation and dopaminergic neuronal apoptosis. Since no current treatment can cure PD, using a suitable PD animal model to evaluate PD motor symptoms' treatment efficacy and identify therapeutic targets and drugs are still needed. Hence, the present review focuses on the latest scientific developments in different neurotoxin-induced PD animal models with their mechanisms of pathogenesis and evaluation methods of PD motor symptoms.

Cordycepin Exerts Neuroprotective Effects via an Anti-Apoptotic Mechanism based on the Mitochondrial Pathway in a Rotenone-Induced Parkinsonism Rat Model

BACKGROUND

Cordycepin (Cor), one of the major bioactive components of the traditional Chinese medicine Cordyceps militaris, has been used in clinical practice for several years. However, its neuroprotective effect remains unknown.

AIMS

The purpose of the study was to evaluate the neuroprotective effects of Cor using a rotenoneinduced Parkinson's Disease (PD) rat model and to delineate the possible associated molecular mechanisms.

METHODS

In vivo, behavioural tests were performed based on the 10-point scale and grid tests. Levels of dopamine and its metabolites in the striatum and the numbers of TH-positive neurons in the Substantia Nigra pars compacta (SNpc) were investigated by high-performance liquid chromatography with electrochemical detection and immunohistochemical staining, respectively. In vitro, cell apoptosis rates and Mitochondrial Membrane Potential (MMP) were analysed by flow cytometry and the mRNA and protein levels of Bax, Bcl-2, Bcl-xL, Cytochrome c (Cyt-c), and caspase-3 were determined by quantitative real-time PCR and western blotting.

RESULTS

Showed that Cor significantly improved dyskinesia, increased the numbers of TH-positive neurons in the SNpc, and maintained levels of dopamine and its metabolites in the striatum in rotenone- induced PD rats. We also found that apoptosis was suppressed and the loss of MMP was reversed with Cor treatment. Furthermore, Cor markedly down-regulated the expression of Bax, upregulated Bcl-2 and Bcl-xL, inhibited the activation of caspase-3, and decreased the release of Cyt-c from the mitochondria to the cytoplasm, as compared to those in the rotenone-treated group.

CONCLUSION

Therefore, Cor protected dopamine neurons against rotenone-induced apoptosis by improving mitochondrial dysfunction in a PD model, demonstrating its therapeutic potential for this disease.

The beneficial effect of vanillin on 6-hydroxydopamine rat model of Parkinson's disease

BACKGROUND

Parkinson's disease (PD) is a progressive neurodegenerative disorder that is related to neuroinflammation. Vanillin, which possesses both antioxidant, and anti-inflammatory properties, can be a candidate for neuroprotection in PD.

OBJECTIVE

This study was aimed to investigate the effects of vanillin on the 6-hydroxydopamine (6-OHDA) rodent model of PD.

METHODS

Male Wistar rats were administrated intraperitoneal (i.p) or oral vanillin at a dose of 20 mg/kg/day for 7 days that was started at three days before or seven days after intracerebral injection of 6-OHDA. The 6-OHDA-induced lesions were assessed behaviorally using the apomorphine rotation test, neurochemically via measuring striatal dopamine concentrations, and through immunohistochemistry.

RESULTS

Both oral and IP vanillin at three days before or seven days after 6-OHDA lesioning exhbited significantly lower tight contralateral rotations upon apomorphine challenge, and higher striatal dopamine concentrations.

CONCLUSIONS

Vanillin seems to offer protective properties against 6-OHDA lesion via preserving striatal dopamine levels.

Vanillin Prevents Doxorubicin-Induced Apoptosis and Oxidative Stress in Rat H9c2 Cardiomyocytes

Doxorubicin (doxo) is an effective anticancer compound in several tumor types. However, as a consequence of oxidative stress induction and ROS overproduction, its high cardiotoxicity demands urgent attention. Vanillin possesses antioxidant, antiproliferative, antidepressant and anti-glycating properties. Therefore, we investigated the potential vanillin protective effects against doxo-induced cardiotoxicity in H9c2 cells. Using multiparametric approach, we demonstrated that vanillin restored both cell viability and damage in response to doxo exposure. Contextually, vanillin decreased sub-G1 appearance and caspase-3 and PARP1 activation, reducing the doxo-related apoptosis induction. From a mechanistic point of view, vanillin hindered doxo-induced ROS accumulation and impaired the ERK phosphorylation. Notably, besides the cardioprotective effects, vanillin did not counteract the doxo effectiveness in osteosarcoma cells. Taken together, our results suggest that vanillin ameliorates doxo-induced toxicity in H9c2 cells, opening new avenues for developing alternative therapeutic approaches to prevent the anthracycline-related cardiotoxicity and to improve the long-term outcome of antineoplastic treatment.

History repeats itself: Role of characterizing flavors on nicotine use and abuse

The popularity of e-cigarettes has skyrocketed in recent years, and most vapers use flavored e-cigarette products. Consumption of flavored e-cigarettes exceeds that of combustible cigarettes and other tobacco products among adolescents, who are particularly vulnerable to becoming nicotine dependent. Flavorings have been used by the tobacco industry since the 17th century, but the use of flavors by the e-cigarette industry to create products with "characterizing" flavors (i.e. flavors other than tobacco or menthol) has sparked a public health debate. This review addresses the possibility that characterizing flavors make nicotine more appealing, rewarding and addictive. It also discusses ways in which preclinical and clinical studies could improve our understanding of the mechanisms by which flavors may alter nicotine reward and reinforcement. This article is part of the special issue on 'Contemporary Advances in Nicotine Neuropharmacology'.

Vanillin and vanillic acid modulate antioxidant defense system via amelioration of metabolic complications linked to Fe2+-induced brain tissues damage

The therapeutic effect of phenolics on neurodegenerative diseases has been attributed to their potent antioxidant properties. In the present study, the neuroprotective activities of vanillin and vanillic acid were investigated in Fe2+- induced oxidative toxicity in brain tissues by investigating their therapeutic effects on oxidative imbalance, cholinergic and nucleotide-hydrolyzing enzymes activities, dysregulated metabolic pathways. Their cytotoxicity was investigated in hippocampal neuronal cell lines (HT22). The reduced glutathione level, SOD and catalase activities were ameliorated in tissues treated with the phenolics, with concomitant depletion of malondialdehyde and nitric oxide levels. They inhibited acetylcholinesterase and butyrylcholinesterase activities, while concomitantly elevated ATPase activity. Treatment with vanillin led to restoration of oxidative-depleted metabolites and reactivation of the pentose phosphate and purine metabolism pathways, with concomitant activation of pathways for histidine and selenoamino metabolisms. While vanillic acid restored and reactivated oxidative-depleted metabolites and pathways but did not activate any additional pathway. Both phenolics portrayed good binding affinity for catalase, with vanillic acid having the higher binding energy of -7.0 kcal/mol. Both phenolics were not cytotoxic on HT22 cells, and their toxicity class were predicted to be 4. Only vanillin was predicted to be permeable across the blood brain barrier (BBB). These results insinuate that vanillin and vanillic acid confer a neuroprotective effect on oxidative brain damage, when vanillin being the most potent.

O-Vanillin Attenuates the TLR2 Mediated Tumor-Promoting Phenotype of Microglia

Malignant gliomas are primary brain tumors with poor prognoses. These tumors are infiltrated by brain intrinsic microglia and peripheral monocytes which promote glioma cell invasion. In our previous studies, we discovered that the activation of Toll-like receptor 2 (TLR2) on microglia/brain macrophages converts them into a protumorigenic phenotype through the induction of matrix metalloproteinases (MMP) 9 and 14. In the present study, we used in vitro and in situ microglia-glioma interaction experimental models to test the impact of a novel inhibitor of TLR 2, ortho vanillin (O-Vanillin) to block TLR2 mediated microglia protumorigenic phenotype. We demonstrate that O-Vanillin inhibits the TLR2 mediated upregulation of MMP 9, MMP 14, IL 6 and iNOS expression. Similarly, the glioma supernatant induced MMP 9 and MMP 14 expression in murine and human microglia is abrogated by O-Vanillin treatment. O-Vanillin is not toxic for microglia, astrocytes or oligodendrocytes. Glioma growth in murine brain slice cultures is significantly reduced after treatment with O-Vanillin, and this reduced glioma growth depends on the presence of microglia. In addition, we also found that O-Vanillin inhibited the glioma induced proliferation of murine primary microglia. In summary, O-Vanillin attenuates the pro-tumorigenic phenotype of microglia/brain macrophages and thus qualifies as a candidate for glioma therapy.

Neuroprotective Effects of Pomegranate Juice against Parkinson's Disease and Presence of Ellagitannins-Derived Metabolite-Urolithin A-In the Brain

Pomegranate juice is a rich source of ellagitannins (ETs) believed to contribute to a wide range of pomegranate's health benefits. While a lot of experimental studies have been devoted to Alzheimer disease and hypoxic-ischemic brain injury, our knowledge of pomegranate's effects against Parkinson's disease (PD) is very limited. It is suggested that its neuroprotective effects are mediated by ETs-derived metabolites-urolithins. In this study, we examined the capability of pomegranate juice for protection against PD in a rat model of parkinsonism induced by rotenone. To evaluate its efficiency, assessment of postural instability, visualization of neurodegeneration, determination of oxidative damage to lipids and α-synuclein level, as well as markers of antioxidant defense status, inflammation, and apoptosis, were performed in the midbrain. We also check the presence of plausible active pomegranate ETs-derived metabolite, urolithin A, in the plasma and brain. Our results indicated that pomegranate juice treatment provided neuroprotection as evidenced by the postural stability improvement, enhancement of neuronal survival, its protection against oxidative damage and α-synuclein aggregation, the increase in mitochondrial aldehyde dehydrogenase activity, and maintenance of antiapoptotic Bcl-xL protein at the control level. In addition, we have provided evidence for the distribution of urolithin A to the brain.

Protective effect of vanillin on diabetic nephropathy by decreasing advanced glycation end products in rats

AIMS

Diabetic nephropathy (DN) is a common chronic microvascular complication of both types of diabetes mellitus, which leads to renal dysfunction and subsequent need of dialysis and organ transplantation. Advanced glycation end products (AGEs) are metabolic consequence of hyperglycemia and are main contributory factor in the DN pathogenesis through mediating establishment of oxidative status and chronic inflammatory milieu. This study aimed to explore the impact of vanillin on preventing the progression of DN.

MAIN METHODS

Experimental DN model was established in rats utilizing streptozotocin. Serum concentration of AGEs and Interleukin-6 (IL-6) and transforming growth factor β1 (TGFβ1) levels in kidney homogenate were assessed using ELISA technique. Also, we evaluated the expression of nuclear factor kappa B (NF-κB) using immunohistochemistry.

KEY FINDINGS

Treatment with vanillin for 8 weeks significantly ameliorated DN. Vanillin significantly decreased hyperglycemia and improved kidney function reflected by decreased serum levels of blood urea nitrogen, creatinine, and decreased proteinuria. Also, vanillin significantly decreased malondialdehyde content and elevated superoxide dismutase activity in renal tissues. Moreover, vanillin decreased renal expression of NF-κB and renal concentrations of IL-6, TGFβ1 and collagen. In addition, vanillin significantly decreased serum AGEs concentration. Also, vanillin attenuated histological abnormalities in kidney architecture.

SIGNIFICANCE

Vanillin, which is a cheap and abundant natural product, exhibited anti-AGEs, antioxidant, anti-inflammatory and anti-fibrotic activities. These activities might be helpful and potent mechanisms in preventing the progression of DN.

Methyl jasmonate ameliorates rotenone-induced motor deficits in rats through its neuroprotective activity and increased expression of tyrosine hydroxylase immunopositive cells

Decreased tyrosine hydroxylase (TH) activity, due to degeneration of dopaminergic neurons contributes to the low dopamine content and the motor deficits that characterized Parkinson's disease (PD). This study examines the effect of methyl jasmonate (MJ), a neuroprotective bioactive compound isolated from jasminum grandiflorum, on motor functions, immunopositive cells of TH, dendritic neurons and dopamine contents in rotenone (Rot)-treated rats. Rats pretreated daily with MJ (100 mg/kg, i.p) for 21 days also received Rot (2.5 mg/kg, i.p.) 30 min after each pretreatment for every 48 h for 21 days. Motor functions were assessed on day 22. The specific brain regions of the rats were processed for determination of dopamine contents, immunopositive cells of TH, neuronal cell morphology and dendritic aborizations. Rot impaired locomotion and rearing behavior, and decreased dopamine content in the striatum, prefrontal cortex and midbrain. It further reduced the expression of TH in the substantia nigra and striatum relative to vehicle-control (p < 0.05). Histopathologic studies revealed that Rot-treated rats had degenerated neurons with pyknotic nuclei and loss of nigrostriatal neuronal cells. Rot also altered the nigrostriatal dendritic neuronal networks, decreased the dendritic length and spine density. However, pretreatment with MJ improved motor deficits, increased TH activity and dopamine contents in the specific brain regions of Rot-treated rats. MJ also attenuated the cyto-architectural distortions, loss of neuronal cells and dendritic aborizations of the striatum of Rot-treated rats. These findings suggest that MJ may reverse the motor deficits associated with PD by modifying the key pathological abnormalities involved in the disease progression.

Ethyl Vanillin Protects against Kidney Injury in Diabetic Nephropathy by Inhibiting Oxidative Stress and Apoptosis

Diabetes-induced oxidative stress and apoptosis is regarded as a critical role in the pathogenesis of diabetic nephropathy (DN). Treating diabetes-induced kidney damage and renal dysfunction has been thought a promising therapeutic option to attenuate the development and progression of DN. In this study, we investigated the renoprotective effect of ethyl vanillin (EVA), an active analogue of vanillin isolated from vanilla beans, on streptozotocin- (STZ-) induced rat renal injury model and high glucose-induced NRK-52E cell model. The EVA treatment could strongly improve the deterioration of renal function and kidney cell apoptosis in vivo and in vitro. Moreover, treating with EVA significantly decreased the level of MDA and reactive oxygen species (ROS) and stabilized antioxidant enzyme system in response to oxidative stress by enhancing the activity of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) in vivo and in vitro. Furthermore, EVA also markedly suppressed cleaved caspase-3, Bax, and nuclear transcription factor erythroid 2-related factor (Nrf2) expression in STZ-induced rats. Therefore, these results of our investigation provided that EVA might protect against kidney injury in DN by inhibiting oxidative stress and cell apoptosis.

Apelin-36 mediates neuroprotective effects by regulating oxidative stress, autophagy and apoptosis in MPTP-induced Parkinson's disease model mice

Parkinson's disease (PD), a common human neurodegenerative disorder, is characterized by the presence of intraneuronal Lewy bodies composed principally of abnormal aggregated and post-translationally modified α-synuclein. In our previous research, we have demonstrated the neuroprotective effect of Apelin-36, a neuroendocrine peptide in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridin (MPTP)-lesioned PD model mice. Therefore, this study was designed to evaluate the neuroprotective mechanism of Apelin-36 against MPTP-induced neurotoxicity in mice. The results showed that MPTP-induced the depletion of dopamine in the striatum (STR) was partially reversed by Apelin-36. Apelin-36 also improved the activity of antioxidant system including superoxide dismutase (SOD) and glutathione (GSH), and decreased the overproduction of malondialdehyde (MDA) in the substantia nigra pars compacta (SNpc) and STR of MPTP-treated mice. Moreover, Apelin-36 downregulated inducible nitric oxide synthase (iNOS) and nitrated α-synuclein expression. Furthermore, Apelin-36 significantly promoted autophagy indicated by the up-regulation of LC3-II and Beclin1 and inhibition of p62 expression in the SNpc and STR of MPTP-treated mice. The protective effect of Apelin-36 was also associated with the inhibition of the apoptosis signal-regulating kinase 1 (ASK1)/c-Jun N-terminal kinase (JNK) signaling pathway and inactivation of caspase-3. Taken together, our findings demonstrated that the neuroprotective mechanism of Apelin-36 against MPTP-induced neurotoxicity in mice might be related to decreasing the aggregation of nitrated α-synuclein and alleviating oxidative stress as well as promoting autophagy and inhibiting ASK1/JNK/caspase-3 apoptotic pathway, which provides a novel strategy for PD treatment.