Current Trends in Neurodegeneration: Cross Talks between Oxidative Stress, Cell Death, and Inflammation

Cholinergic Inhibition and Antioxidant Potential of Gongronema latifolium Benth Leaf in Neurodegeneration: Experimental and In Silico Study

The use of Gongronema latifolium for the management of various forms of neurological disorders has generated a lot of interest in the need to further investigate its neurotherapeutic constituents. This work, therefore, focused on assessing the inhibitory potential of selected bioactive components derived from G. latifolium against key neurotherapeutic targets and oxidant species associated with neurodegeneration using in vitro analysis and biomolecular modelling. G. latifolium methanol extract (GLME), solvent partition, chromatographic fractions (A-F) of GLME and pregnane compounds (Iloneoside and marsectohexol) derived from fraction-B with the highest activity were investigated for in vitro acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and monoamine oxidase (MAO) inhibition in addition to their in vitro antioxidant activities. The interactions of iloneoside, marsectohexol, and reference drugs with human acetylcholinesterase, butyrylcholinesterase, and β-secretase (BACE-1) were further assessed using molecular docking, binding free energy calculations, cluster analysis, and molecular dynamics simulations. The GLME and fractions inhibited the activities of both acetylcholinesterase and butyrylcholinesterase in a dose-dependent manner. Iloneoside and marsectohexol exhibited in vitro concentration-dependent inhibitory activities against acetylcholinesterase (IC50 = 19.28, 184.9 µM, respectively) and butyrylcholinesterase (IC50 = 30.75, 43.4 µM, respectively). These compounds also possess ferric ion-reducing, hydroxyl, and superoxide radical-scavenging activities. Iloneoside had the highest docking scores of -9.8, -9.9 -9.4 Kcal for AChE, BChE, and BACE1, respectively. The stability of the interaction of the bioactive compounds with the catalytic residues of the protein targets was preserved in a 100 ns molecular dynamics simulation. Iloneoside, a rare pregnane glycoside, was identified as a neurotherapeutic constituent of G. latifolium leaf. Further studies are suggested to investigate the neurotherapeutic potential in animal models.

Pharmacological insights and role of bufalin (bufadienolides) in inflammation modulation: a narrative review

Bufadienolides, specifically bufalin, have garnered attention for their potential therapeutic application in modulating inflammatory pathways. Bufalin is derived from toad venom and exhibits promising anti-inflammatory properties. Its anti-inflammatory effects have been demonstrated by influencing crucial signaling pathways like NF-B, MAPK, and JAK-STAT, resulting in the inhibition of pro-inflammatory substances like cytokines, chemokines, and adhesion molecules. Bufalin blocks inflammasome activation and reduces oxidative stress, hence increasing its anti-inflammatory properties. Bufalin has shown effectiveness in reducing inflammation-related diseases such as cancer, cardiovascular problems, and autoimmune ailments in preclinical investigations. Furthermore, producing new approaches of medication delivery and combining therapies with bufalin shows potential for improving its effectiveness and reducing adverse effects. This review explores the pharmacological effects and mechanistic approaches of bufalin as an anti-inflammatory agent, which further highlights its potential for therapy and offers the basis for further study on its therapeutic application in inflammation-related disorders.

Effects of kaempherol-3-rhamnoside on metabolic enzymes and AMPK in the liver tissue of STZ-induced diabetes in mice

Diabetes mellitus (DM) is a chronic metabolic disorder characterized by persistent hyperglycemia. It involves disturbances in carbohydrate, fat, and protein metabolism due to defects in insulin secretion, insulin action, or both. Novel therapeutic approaches are continuously being explored to enhance metabolic control and prevent complications associated with the disease. This study investigates the therapeutic potential of kaempherol-3-rhamnoside, a flavonoid, in managing diabetes by modulating the AMP-activated protein kinase (AMPK) pathway and improving metabolic enzyme activities in streptozotocin (STZ) -induced diabetic mice. Diabetic mice were treated with varying doses of kaempherol-3-rhamnoside and/or insulin over a 28-day period. Glycolytic and gluconeogenesis enzyme activities in the liver, fasting blood glucose levels, serum insulin levels, lipid profiles and oxidative stress markers were assessed. Treatment with kaempherol-3-rhamnoside significantly improved glycolytic enzyme activities, reduced fasting blood glucose, and enhanced insulin levels compared to diabetic controls. The compound also normalized lipid profiles and reduced oxidative stress in the liver, suggesting its potential in reversing diabetic dyslipidemia and oxidative damage. Furthermore, kaempherol-3-rhamnoside activated the AMPK pathway, indicating a mechanism through which it could exert its effects. Kaempherol-3-rhamnoside exhibits promising antidiabetic properties, potentially through AMPK pathway activation and metabolic enzyme modulation. These findings support its potential use as an adjunct therapy for diabetes management. Further clinical studies are warranted to validate these results in human subjects.

Pharmacophore-based virtual screening of commercial databases against β-secretase 1 for drug development against Alzheimer's disease

β-secretase 1, one of the most important proteins, is an aspartate protease. This membrane-associated protein is used for treating Alzheimer's disease (AD). Several inhibitors have been pursued against β-secretase 1, but they still have not resulted effectively. Virtual screening based on pharmacophores has been shown to be useful for lead optimization and hit identification in the preliminary phase of developing a new drug. Here, we screen the commercially available databases to find the hits against β-secretase 1 for drug discovery against AD. Virtual screening for 200,000 compounds was done using the database from the Vitas-M Laboratory. The phase screen score was utilized to assess the screened hits. Molecular docking was performed on compounds with phase scores >1.9. According to the study, the 66H ligand of the crystal structure has the maximum performance against β-secretase 1. The redocking of the co-crystal ligand showed that the docked ligand was seamlessly united with the crystal structure. The reference complex had three hydrogen bonds with Asp93, Asp289, and Gly291; one van der Waals interaction with Gly74; and three hydrophobic interactions. After equilibration, the RMSD of the reference compound sustained a value of ∼1.5 Å until 30 ns and then boosted to 2.5 Å. On comparison, the RMSD of the S1 complex steadily increased to ∼2.5 Å at 15 ns, displayed slight aberrations at approximately ∼2.5-3 Å until 80 ns, and then achieved steadiness toward the end of the simulation. The arrangements of proteins stayed condensed during the mockup when bonded to these complexes as stable Rg values showed. Furthermore, the MM/GBSA technique was employed to analyze both compounds' total binding free energies (ΔGtotal). Our research study provides a new understanding of using 66H as anti-β-secretase 1 for drug development against AD.

Pterostilbene alleviates MPTP-induced neurotoxicity by targeting neuroinflammation and oxidative stress

Pterostilbene (PTE), a naturally occurring phenolic compound primarily found in blueberries, demonstrates neuroprotective properties. However, the role of PTE in Parkinson's disease (PD) remains unclear. This study aimed to investigate the neuroprotective role of PTE in the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced PD animal model. Our findings demonstrate that administering PTE effectively reversed the diminished levels of dopamine in the striatum, thereby ameliorating motor impairments in the MPTP model. Moreover, PTE administration mitigated the loss of dopaminergic (DA) neurons and reduced the upregulation of α-synuclein (α-syn) induced by MPTP. Mechanistic analysis revealed that PTE administration inhibited the activation of microglia and astrocytes, as well as pro-inflammatory factors such as TNF-α and IL-1β in the MPTP model. Additionally, PTE administration decreased MPTP-induced levels of reactive oxygen species (ROS) and malondialdehyde (MDA), while increasing total antioxidant capacity (TAOC) and superoxide dismutase (SOD) activity, thereby attenuating oxidative stress. Collectively, these findings demonstrate that PTE exerts neuroprotective effects in the MPTP mouse model of PD by suppressing neuroinflammation and oxidative stress. Thus, PTE holds promise as a therapeutic agent for PD.

Induced pluripotent stem cell models as a tool to investigate and test fluid biomarkers in Alzheimer's disease and frontotemporal dementia

Neurodegenerative diseases are increasing in prevalence and comprise a large socioeconomic burden on patients and their caretakers. The need for effective therapies and avenues for disease prevention and monitoring is of paramount importance. Fluid biomarkers for neurodegenerative diseases have gained a variety of uses, including informing participant selection for clinical trials, lending confidence to clinical diagnosis and disease staging, determining prognosis, and monitoring therapeutic response. Their role is expected to grow as disease-modifying therapies start to be available to a broader range of patients and as prevention strategies become established. Many of the underlying molecular mechanisms of currently used biomarkers are incompletely understood. Animal models and in vitro systems using cell lines have been extensively employed but face important translatability limitations. Induced pluripotent stem cell (iPSC) technology, where a theoretically unlimited range of cell types can be reprogrammed from peripheral cells sampled from patients or healthy individuals, has gained prominence over the last decade. It is a promising avenue to study physiological and pathological biomarker function and response to experimental therapeutics. Such systems are amenable to high-throughput drug screening or multiomics readouts such as transcriptomics, lipidomics, and proteomics for biomarker discovery, investigation, and validation. The present review describes the current state of biomarkers in the clinical context of neurodegenerative diseases, with a focus on Alzheimer's disease and frontotemporal dementia. We include a discussion of how iPSC models have been used to investigate and test biomarkers such as amyloid-β, phosphorylated tau, neurofilament light chain or complement proteins, and even nominate novel biomarkers. We discuss the limitations of current iPSC methods, mentioning alternatives such as coculture systems and three-dimensional organoids which address some of these concerns. Finally, we propose exciting prospects for stem cell transplantation paradigms using animal models as a preclinical tool to study biomarkers in the in vivo context.

Identification of potential inhibitors of cholinergic and β-secretase enzymes from phytochemicals derived from Gongronema latifolium Benth leaf: an integrated computational analysis

Neurodegenerative disorders (NDDs) are associated with increased activities of the brain acetylcholinesterase (AChE), butyrylcholinesterase (BChE) and β-secretase enzyme (BACE1). Inhibition of these enzymes affords therapeutic option for managing NDDs such as Alzheimer's disease (AD) and Parkinson's disease (PD). Although, Gongronema latifolium Benth (GL) has been widely documented in ethnopharmacological and scientific reports for the management of NDDs, there is paucity of information on its underlying mechanism and neurotherapeutic constituents. Herein, 152 previously reported Gongronema latifolium derived-phytochemicals (GLDP) were screened against hAChE, hBChE and hBACE-1 using molecular docking, molecular dynamics (MD) simulations, free energy of binding calculations and cluster analysis. The result of the computational analysis identified silymarin, alpha-amyrin and teraxeron with the highest binding energies (-12.3, -11.2, -10.5 Kcal/mol) for hAChE, hBChE and hBACE-1 respectively as compared with those of the reference inhibitors (-12.3, -9.8 and - 9.4 for donepezil, propidium and aminoquinoline compound respectively). These best docked phytochemicals were found to be orientated in the hydrophobic gorge where they interacted with the choline-binding pocket in the A-site and P-site of the cholinesterase and subsites S1, S3, S3' and flip (67-75) residues of the pocket of the BACE-1. The best docked phytochemicals complexed with the target proteins were stable in a 100 ns molecular dynamic simulation. The interactions with the catalytic residues were preserved during the simulation as observed from the MMGBSA decomposition and cluster analyses. The presence of these phytocompounds most notably silymarin, which demonstrated dual high binding tendencies to both cholinesterases, were identified as potential neurotherapeutics subject to further investigation.

Mitochondrial DNA Leakage and cGas/STING Pathway in Microglia: Crosstalk Between Neuroinflammation and Neurodegeneration

Neurodegenerative diseases, characterized by abnormal deposition of misfolded proteins, often present with progressive loss of neurons. Chronic neuroinflammation is a striking hallmark of neurodegeneration. Microglia, as the primary immune cells in the brain, is the main type of cells that participate in the formation of inflammatory microenvironment. Cytoplasmic free mitochondrial DNA (mtDNA), a common component of damage-associated molecular patterns (DAMPs), can activate the cGas/stimulator of interferon genes (STING) signalling, which subsequently produces type I interferon and proinflammatory cytokines. There are various sources of free mtDNA in microglial cytoplasm, but mitochondrial oxidative stress accumulation plays the vital role. The upregulation of cGas/STING pathway in microglia contributes to the abnormal and persistent microglial activation, accompanied by excessive secretion of neurotoxic inflammatory mediators such as interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α), which exacerbates the damage of neurons and promotes the development of neurodegeneration. Currently, novel therapeutic approaches need to be found to delay the progression of neurodegenerative disorders, and regulation of the cGas/STING signaling in microglia may be a potential target.

Tremendous Fidelity of Vitamin D3 in Age-related Neurological Disorders

Vitamin D3 (VD) is a secosteroid hormone and shows a pleiotropic effect in brain-related disorders where it regulates redox imbalance, inflammation, apoptosis, energy production, and growth factor synthesis. Vitamin D3's active metabolic form, 1,25-dihydroxy Vitamin D3 (1,25(OH)2D3 or calcitriol), is a known regulator of several genes involved in neuroplasticity, neuroprotection, neurotropism, and neuroinflammation. Multiple studies suggest that VD deficiency can be proposed as a risk factor for the development of several age-related neurological disorders. The evidence for low serum levels of 25-hydroxy Vitamin D3 (25(OH)D3 or calcidiol), the major circulating form of VD, is associated with an increased risk of Alzheimer's disease (AD), Parkinson's disease (PD), Huntington's disease (HD), dementia, and cognitive impairment. Despite decades of evidence on low VD association with neurological disorders, the precise molecular mechanism behind its beneficial effect remains controversial. Here, we will be delving into the neurobiological importance of VD and discuss its benefits in different neuropsychiatric disorders. The focus will be on AD, PD, and HD as they share some common clinical, pathological, and epidemiological features. The central focus will be on the different attributes of VD in the aspect of its anti-oxidative, anti-inflammatory, anti-apoptotic, anti-cholinesterase activity, and psychotropic effect in different neurodegenerative diseases.

Inflammation in Posttraumatic Stress Disorder: Dysregulation or Recalibration?

Despite ample experimental data indicating a role of inflammatory mediators in the behavioral and neurobiological manifestations elicited by exposure to physical and psychologic stressors, causative associations between systemic low-grade inflammation and central nervous system inflammatory processes in posttraumatic stress disorder (PTSD) patients remain largely conceptual. As in other stress-related disorders, pro-inflammatory activity may play an equivocal role in PTSD pathophysiology, one that renders indiscriminate employment of anti-inflammatory agents of questionable relevance. In fact, as several pieces of preclinical and clinical research convergingly suggest, timely and targeted potentiation rather than inhibition of inflammatory responses may actually be beneficial in patients who are characterized by suppressed microglia function in the face of systemic low-grade inflammation. The deleterious impact of chronic stress-associated inflammation on the systemic level may, thus, need to be held in context with the - often not readily apparent - adaptive payoffs of low-grade inflammation at the tissue level.

The Relationship Between Oxidative Stress, Selenium, and Cumulative Risk in Metabolic Syndrome

BACKGROUND/AIM

Oxidative stress in association with metabolic syndrome represents a complex disease entity that has emerged as a significant public health challenge, and it is closely linked to an elevated risk of cardiovascular disease, type 2 diabetes, and even cancer. The objective of this study was to investigate the effectiveness of selenium supplementation in managing oxidative stress while considering a well-balanced diet based on a healthy lifestyle and diet therapy.

PATIENTS AND METHODS

The study included a total of 206 participants divided into three groups: the control group consisting of 35 individuals (17.0%) named LC, the diet therapy group comprising 119 individuals (57.8%) named LD, and the diet therapy group supplemented with selenium consisting of 52 individuals (25.2%) named LD+Se. Various clinical parameters such as body mass index (BMI), weight status, fat mass, visceral fat, and sarcopenia index, as well as paraclinical parameters including the HOMA index, cholesterol, triglycerides, C-reactive protein, and HGZ, were evaluated. Additionally, oxidative stress parameters using the FORD, FORT and MIXT tests were measured.

RESULTS

Selenium supplementation, along with FORD and FORT tests, demonstrated effectiveness in individuals with chronic venous disease, with a significantly greater decrease observed in those with chronic venous disease in the LD+Se group.

CONCLUSION

Physiological aging has an important role in triggering or aggravating oxidative stress, and the use of antioxidant products such as selenium can reduce this process.

The protective effect of apigenin against inorganic arsenic salt-induced toxicity in PC12 cells

Poisoning by arsenic affects people worldwide, and many human illnesses and health issues, including neurotoxicity, have been linked to chronic exposure to arsenic. When exposed to arsenic, the body produces intracellular reactive oxygen species (ROS), which influence a variety of alterations in cellular activity and directly harm molecules through oxidation. Arsenic-induced lesions are improved by antioxidants with the ability to lower ROS levels. Therefore, the current research aimed to assess how well apigenin protected PC12 cells from the toxicity caused by inorganic arsenic salt (iAs). For 24 and 48 h, iAs and/or apigenin were applied to PC12 cells. Then, oxidative stress indicators like malondialdehyde (MDA), nitric oxide (NO), and ROS in addition to the enzymatic and non-enzymatic antioxidant molecules such as catalase (CAT), glutathione (GSH), and superoxide dismutase (SOD) were assessed. Moreover, after exposure to iAs, PC12 was examined for nuclear factor erythroid 2-related factor 2 (Nrf2) expression to clarify how apigenin manifests its neuroprotection. Furthermore, NF-kB p65 concentration and IL-1B, IL-6, and TNF-α mRNA expression were measured to assess neuroinflammation. Bax, caspase-3, and Bcl-2 levels were measured to investigate apigenin's potential to protect PC12 cells from iAs poisoning. The obtained results revealed that, the cell survival rate in the iAs group was significantly lower (P < 0.05), and the number of viable cells steadily increased after apigenin treatment. Furthermore, the study found that iAs decreased GSH, CAT, and SOD in the PC12 cells while increasing ROS, MDA, and NO levels. In PC12 cells, the capacity of iAs to cause oxidative stress was linked to the induction of neuroinflammation and apoptosis. Interestingly, apigenin pre-treatment of PC12 cells resulted in exceptional protection against iAs-induced neuroinflammation, oxidative stress, and apoptotic cell death. Nrf2 upregulation in PC12 cells may explain the neuroprotection effect of apigenin against iAs toxicity. In conclusion, the obtained results of the present study have clinical significance and indicate that apigenin is a promising candidate for shielding the nervous system from toxic effects caused by arsenic. These findings require further investigation using in vivo experimental models.

Oxidative stress, the blood-brain barrier and neurodegenerative diseases: The critical beneficial role of dietary antioxidants

In recent years, growing awareness of the role of oxidative stress in brain health has prompted antioxidants, especially dietary antioxidants, to receive growing attention as possible treatments strategies for patients with neurodegenerative diseases (NDs). The most widely studied dietary antioxidants include active substances such as vitamins, carotenoids, flavonoids and polyphenols. Dietary antioxidants are found in usually consumed foods such as fresh fruits, vegetables, nuts and oils and are gaining popularity due to recently growing awareness of their potential for preventive and protective agents against NDs, as well as their abundant natural sources, generally non-toxic nature, and ease of long-term consumption. This review article examines the role of oxidative stress in the development of NDs, explores the 'two-sidedness' of the blood-brain barrier (BBB) as a protective barrier to the nervous system and an impeding barrier to the use of antioxidants as drug medicinal products and/or dietary antioxidants supplements for prevention and therapy and reviews the BBB permeability of common dietary antioxidant suplements and their potential efficacy in the prevention and treatment of NDs. Finally, current challenges and future directions for the prevention and treatment of NDs using dietary antioxidants are discussed, and useful information on the prevention and treatment of NDs is provided.

Acacia catechu Willd. and Acacia arabica Willd. decrease the extent of anxiety behavior by reducing oxidative stress and moderating neurochemicals

ETHNOPHARMACOLOGICAL RELEVANCE

Anxiety is a very common psychiatric problem. It affects a large group of people in the world population. Acacia genus is well known for phenolic and flavonoid content. Literature showed its potential for various biological activities and is useful in the treatment of chest pain, asthma, bronchitis, wounds, mouth ulcer, colic, vitiligo, sore throat, inflammation, diarrhoea and also used as tonic.

AIM OF THE STUDY

The present study was conducted to assess the antianxiety potential of two plants Acacia catechu Willd. and Acacia arabica Willd. from the common family Fabaceae.

MATERIALS AND METHODS

The stems of both plants were used for this purpose. Plants were subjected to complete exhaustive successive extraction using petroleum ether, chloroform, ethanol, and water as solvent. After pharmacognostic and phytochemical investigation, antianxiety activity was conducted on Swiss albino mice at different dose levels (100, 200, 300, & 400 mg/kg body weight p.o.) for all successive extracts of both plants. Two active extracts from each plant were further assessed for anxiolytic potential using the open-field test and mirror chamber test. One extract with the maximum response from each plant was further screened using mCPP-induced anxiety test.

RESULTS

The stem of ethanol extract of A. catechu showed comparable antianxiety activity at 400 mg/kg to the standard drug diazepam (2.5 mg/kg). Improved SOD, catalase, and LPO levels were noted after administration of A. catechu ethanolic extract at 400 mg/kg.

CONCLUSIONS

In conclusion, A. catechu ethanolic extract improved anxiety symptoms at dose-dependent levels in mice.

Underlying Mechanisms of Brain Aging and Neurodegenerative Diseases as Potential Targets for Preventive or Therapeutic Strategies Using Phytochemicals

During aging, several tissues and biological systems undergo a progressive decline in function, leading to age-associated diseases such as neurodegenerative, inflammatory, metabolic, and cardiovascular diseases and cancer. In this review, we focus on the molecular underpinning of senescence and neurodegeneration related to age-associated brain diseases, in particular, Alzheimer's and Parkinson's diseases, along with introducing nutrients or phytochemicals that modulate age-associated molecular dysfunctions, potentially offering preventive or therapeutic benefits. Based on current knowledge, the dysregulation of microglia genes and neuroinflammation, telomere attrition, neuronal stem cell degradation, vascular system dysfunction, reactive oxygen species, loss of chromosome X inactivation in females, and gut microbiome dysbiosis have been seen to play pivotal roles in neurodegeneration in an interactive manner. There are several phytochemicals (e.g., curcumin, EGCG, fucoidan, galangin, astin C, apigenin, resveratrol, phytic acid, acacetin, daucosterol, silibinin, sulforaphane, withaferin A, and betulinic acid) that modulate the dysfunction of one or several key genes (e.g., TREM2, C3, C3aR1, TNFA, NF-kb, TGFB1&2, SIRT1&6, HMGB1, and STING) affected in the aged brain. Although phytochemicals have shown promise in slowing down the progression of age-related brain diseases, more studies to identify their efficacy, alone or in combinations, in preclinical systems can help to design novel nutritional strategies for the management of neurodegenerative diseases in humans.

Curcumin derived from medicinal homologous foods: its main signals in immunoregulation of oxidative stress, inflammation, and apoptosis

It has been for thousands of years in China known medicinal homologous foods that can be employed both as foods and medicines to benefit human and animal health. These edible herbal materials perform divert roles in the regulation of metabolic disorders, cancers, and immune-related diseases. Curcumin, the primary component derived from medicinal homologous foods like curcuma longa rhizome, is reported to play vital actions in organic activities, such as the numerous pharmacological functions including anti-oxidative stress, anti-inflammation and anti/pro-apoptosis in treating various diseases. However, the potential mechanisms of curcumin-derived modulation still need to be developed and attract more attention worldwide. Given that these signal pathways are enrolled in important bioactive reactions, we collected curcumin's last achievements predominantly on the immune-regulation signals with the underlying targetable strategies in the last 10 years. This mini-review will be helpful to accelerate curcumin and other extracts from medicinal homologous foods use in future human clinical applications.

Profiling inflammatory mechanisms, hyperphosphorylated tau of hippocampal tissue and spatial memory following vitamin D3 treatment in the mice model of vascular dementia

BACKGROUND

The aim of this study was to investigate the effect of vitamin D3 (VitD3) on inflammatory mechanisms, hyperphosphorylated tau (p-tau) in the hippocampus, and cognitive impairment of the mouse model of vascular dementia (VaD).

METHODS

In this study, 32 male mice were randomly assigned to the control, VaD, VitD3 (300 IU/Kg/day), and VitD3 (500 IU/Kg/day) groups. VaD and VitD3 groups were gavaged daily for 4 weeks with a gastric needle. For biochemical assessments, blood samples and the hippocampus were isolated. IL-1β and TNF-α were analyzed by ELISA, and p-tau and other inflammatory molecules were measured by western blot.

RESULTS

VitD3 supplements significantly (P < 0.05) decreased the level of inflammatory factors in the hippocampus and prevented apoptosis. However, regarding p-tau in hippocampal tissue, this decrease was not statistically significant (P > 0.05). The results of behavioral assessments showed that VitD3 significantly improved the spatial memory of treated mice.

CONCLUSION

These results suggest that the neuroprotective effects of VitD3 are mainly associated with their anti-inflammatory effects.

In Silico-Guided Rational Drug Design and Synthesis of Novel 4-(Thiophen-2-yl)butanamides as Potent and Selective TRPV1 Agonists

We describe an in silico-guided rational drug design and the synthesis of the suggested ligands, aimed at improving the TRPV1-ligand binding properties and the potency of N-(4-hydroxy-3-methoxybenzyl)-4-(thiophen-2-yl) butanamide I, a previously identified TRPV1 agonist. The docking experiments followed by molecular dynamics simulations and thermodynamic analysis led the drug design toward both the introduction of a lipophilic iodine and a flat pyridine/benzene at position 5 of the thiophene nucleus. Most of the synthesized compounds showed high TRPV1 efficacy and potency as well as selectivity. The molecular modeling analysis highlighted crucial hydrophobic interactions between Leu547 and the iodo-thiophene nucleus, as in amide 2a, or between Phe543 and the pyridinyl moiety, as in 3a. In the biological evaluation, both compounds showed protective properties against oxidative stress-induced ROS formation in human keratinocytes. Additionally, while 2a showed neuroprotective effects in both neurons and rat brain slices, 3a exhibited potent antinociceptive effect in vivo..

Isoimperatorin therapeutic effect against aluminum induced neurotoxicity in albino mice

Background: Although aluminum (Al) is not biologically crucial to the human body, classical studies have demonstrated that excessive human exposure to Al can induce oxidative damage, neuroinflammatory conditions and neurotoxic manifestations implicated in Alzheimer's disease (AD). Exposure to Al was reported to be associated with oxidative damage, neuroinflammation, and to enhance progressive multiregional neurodegeneration in animal models. Several plant-derived natural biomolecules have been recently used to reduce the toxic effects of Al through decreasing the oxidative stress and the associated diseases. A good candidate still to be tested is an active natural furanocoumarin, the isoimperatorin (IMP) that can be extracted from Lemon and lime oils and other plants. Here, we examined the neuroprotective effects of IMP on aluminum chloride (AlCl3)-induced neurotoxicity in albino mice. Methods: Twenty-four male albino mice were used in this study. Mice were randomly devided into 5 groups. The first group was given distilled water as a control, the second group was given AlCl3 orally (10 mg/wt/day) starting from the 2nd week to the end of the 6th week, the third group received AlCl3 orally and IMP interperitoneally, i. p. (30 mg/wt/day) starting from week 2 till week 6 where IMP was supplement 1st and then 4 h later AlCl3 was given to mice. The fourth group received the control (IMP 30 mg/wt, i. p.) from the 2nd week till the end of the experiment. Rodent models of central nervous system (CNS) disorders were assessed using object location memory and Y-maze tests in 6th week began. Essential anti-inflammatory and oxidative stress indicators were evaluated, including interleukin-1 β (IL-1β), tumor necrosis factor α (TNF-α), malondialdehyde (MDA), total antioxidant capacity (TAC), and catalase activity (CAT). In addition, serum levels of brain neurotransmitters such as corticosterone, acetylcholine (ACh), dopamine and serotonin in brain homogenates were measured calorimetrically. Results: The study results revealed that the daily treatment of AlCl3 upregulated the TNF-α and IL-1β levels, increased MDA accumulation, and decreased TAC and CAT activity. In addition, aluminum induced a reduction in concentrations of ACh, serotonin and dopamine in the brain. However, IMP significantly ameliorates the effect of AlCl3 through modulating the antioxidant and regulating the inflammatory response through targeting Nrf2 (NF-E2-related factor 2) and mitogen-activated protein kinase (MAPK). Conclusion: Thus, IMP might be a promising treatment option for neurotoxicity and neurodegenerative diseases, such as Alzheimer's disease and Parkinson's disease, which are associated with neuro-inflammation and oxidative stress.

Neuroprotective effect of total flavonoids in stems and leaves of Glycyrrhiza uralensis Fisch. on oxidative stress in HT-22 cells and Caenorhabditis elegans

The Glycyrrhiza uralensis Fisch. is a common traditional Chinese medicine. However, its aerial part is currently not widely studied and used. Therefore, we aimed to investigate the neuroprotective effects of total flavonoids in aerial stems and leaves of Glycyrrhiza uralensis Fisch. (GSF) by an in vitro LPS-induced HT-22 cell model and an in vivo Caenorhabditis elegans (C. elegans) model. In this study, cell apoptosis was evaluated by CCK-8 and Hoechst 33258 staining in LPS-induced HT-22 cells. Meanwhile, ROS level, mitochondrial membrane potential (MMP), and Ca2+ level were detected by the flow cytometer. In vivo, C. elegans was also investigated the effect of GSF on lifespan, spawning, and paralysis. Moreover, the survival of C. elegans to oxidative stimuli (juglone and H2O2), and the nuclear translocation of DAF-16 and SKN-1 were evaluated. The results showed that GSF could inhibit LPS-induced HT-22 cell apoptosis. Moreover, GSF decreased the levels of ROS, MMP, Ca2+, and malondialdehyde (MDA) and increased the activities of SOD and CAT in HT-22 cells. Furthermore, GSF did not affect the lifespan and laying of eggs of C. elegans N2. However, it delayed paralysis in C. elegans CL4176 in a dose-dependent manner. Meanwhile, GSF increased the survival rate of C. elegans CL2006 after juglone and H2O2 treatment, increased SOD and CAT, and decreased MDA levels. Importantly, GSF promoted the nuclear translocation of DAF-16 and SKN-1 in C. elegans TG356 and LC333, respectively. Taken together, GSF can play a protective role in neuronal cells by inhibiting oxidative stress.

Cucurbita maxima Seeds Reduce Anxiety and Depression and Improve Memory

The current study was planned to assess the neuropharmacological benefits of the Cucurbita maxima seed. These seeds have been conventionally used for the nutritional as well as amelioration of various diseases. However, there was a need to provide a pharmacological basis for such use. Four central nervous system-related functions, that is, anxiety, depression, memory, and motor coordination, were evaluated, and the levels of brain biogenic amines were also assessed. Anxiety was evaluated through selected experimental models, such as light and dark apparatus, elevated plus maze, head dip, and open field test. The head dip test was mainly used to assess exploratory behavior. Depression was assessed by two animal models, that is, the forced swim test and tail suspension test. Memory and learning ability were assessed by the passive avoidance test, stationary rod apparatus, and Morris's water maze test. Motor skilled learning was assessed by stationary rod and rotarod apparatus. Reversed phase high-pressure liquid chromatography was used to determine biogenic amine levels. Results reveal that C. maxima exhibited anxiolytic and antidepressant effects with memory improvement. There was a reduction in the weight of the animal following chronic administration. Furthermore, no remarkable effects were observed on motor coordination. Norepinephrine was found elevated, which may be linked to its antidepressant effects. These biological effects of C. maxima may be due to the presence of secondary metabolites, such as cucurbitacin, beta-sitosterol, polyphenolic compounds, citrulline, kaempferol, arginine, β-carotene, quercetin, and other antioxidants. The outcomes of the present study authenticate that the chronic use of C. maxima seeds reduces the intensity of neurological problems like anxiety and depression.

Development of potent and selective FAAH inhibitors with improved drug-like properties as potential tools to treat neuroinflammatory conditions

The neuroprotective performance against neuroinflammation of the endocannabinoid system (ECS) can be remarkably improved by indirect stimulation mediated by the pharmacological inhibition of the key ECS catabolic enzyme fatty acid amide hydrolase (FAAH). Based on our previous works and aiming to discover new selective FAAH inhibitors , we herein reported a new series of carbamate-based FAAH inhibitors (4a-t) which showed improved drug disposition properties compared to the previously reported analogues 2a-b. The introduction of ionizable functions allowed us to obtain new FAAH inhibitors of nanomolar potency characterized by good water solubility and chemical stability at physiological pH. Interesting structure-activity relationships (SARs), deeply analyzed by molecular docking and molecular dynamic (MD) simulations, were obtained. All the newly developed inhibitors showed an excellent selectivity profile evaluated against monoacylglycerol lipase and cannabinoid receptors. The reversible mechanism of action was determined by a rapid dilution assay. Absence of toxicity was confirmed in mouse fibroblasts NIH3T3 (for compounds 4e, 4g, 4n-o, and 4s) and in human astrocytes cell line 1321N1 (for compounds 4e, 4n, and 4s). The absence of undesired cardiac effects was also confirmed for compound 4n. Selected analogues (compounds 4e, 4g, 4n, and 4s) were able to reduce oxidative stress in 1321N1 astrocytes and exhibited notable neuroprotective effects when tested in an ex vivo model of neuroinflammation.

The neuroprotective effects of targeting key factors of neuronal cell death in neurodegenerative diseases: The role of ER stress, oxidative stress, and neuroinflammation

Neuronal loss is one of the striking causes of various central nervous system (CNS) disorders, including major neurodegenerative diseases, such as Alzheimer's disease (AD), Parkinson's disease (PD), Huntington's disease (HD), and Amyotrophic lateral sclerosis (ALS). Although these diseases have different features and clinical manifestations, they share some common mechanisms of disease pathology. Progressive regional loss of neurons in patients is responsible for motor, memory, and cognitive dysfunctions, leading to disabilities and death. Neuronal cell death in neurodegenerative diseases is linked to various pathways and conditions. Protein misfolding and aggregation, mitochondrial dysfunction, generation of reactive oxygen species (ROS), and activation of the innate immune response are the most critical hallmarks of most common neurodegenerative diseases. Thus, endoplasmic reticulum (ER) stress, oxidative stress, and neuroinflammation are the major pathological factors of neuronal cell death. Even though the exact mechanisms are not fully discovered, the notable role of mentioned factors in neuronal loss is well known. On this basis, researchers have been prompted to investigate the neuroprotective effects of targeting underlying pathways to determine a promising therapeutic approach to disease treatment. This review provides an overview of the role of ER stress, oxidative stress, and neuroinflammation in neuronal cell death, mainly discussing the neuroprotective effects of targeting pathways or molecules involved in these pathological factors.

Neuroprotective Potential of Bacopa monnieri: Modulation of Inflammatory Signals

BACKGROUND

To date, much evidence has shown the increased interest in natural molecules and traditional herbal medicine as alternative bioactive compounds to fight many inflammatory conditions, both in relation to immunomodulation and in terms of their wound healing potential. Bacopa monnieri is a herb that is used in the Ayurvedic medicine tradition for its anti-inflammatory activity.

OBJECTIVE

In this study, we evaluate the anti-inflammatory and regenerative properties of the Bacopa monnieri extract (BME) in vitro model of neuroinflammation.

METHODS

Neuronal SH-SY5Y cells were stimulated with TNFα and IFNγ and used to evaluate the effect of BME on cell viability, cytotoxicity, cytokine gene expression, and healing rate.

RESULTS

Our results showed that BME protects against the Okadaic acid-induced cytotoxicity in SH-SY5Y cells. Moreover, in TNFα and IFNγ primed cells, BME reduces IL-1β, IL-6, COX-2, and iNOS, mitigates the mechanical trauma injury-induced damage, and accelerates the healing of wounds.

CONCLUSION

This study indicates that BME might become a promising candidate for the treatment of neuroinflammation.

Neuropharmacological Study on Capsaicin in Scopolamine-injected Mice

AIM

To evaluate the potential beneficial role of Capsaicin in cognitive dysfunction, mitochondrial impairment, and oxidative damage induced by scopolamine in mice.

BACKGROUND

Capsaicin is the chief phenolic component present in red chili and is responsible for its pungent and spicy flavor. It affects TRPV1 channels in nociceptive sensory neurons and is present in the hippocampus, and hypothalamus of the brains of rodents and humans.

OBJECTIVE

The main objective is to investigate the effective role of capsaicin in attenuating cognitive dysfunction, mitochondrial impairment, and oxidative damage induced by scopolamine in mice and examine the feasible mechanisms.

METHODS

Various doses of capsaicin (5, 10, and 20 mg/kg) were given orally to mice daily for 7 consecutive days after the administration of scopolamine. Various behavioral tests (motor coordination, locomotor counts, hole board test) and biochemical assay (Pro-inflammatory cytokines, catalase, lipid peroxidation, nitrite, reduced glutathione, and superoxide dismutase), mitochondrial complex (I, II, III, and IV) enzyme activities, and mitochondrial permeability transition were evaluated in the distinct regions of the brain.

RESULTS

Scopolamine-treated mice showed a considerable reduction in the entries and duration in the light zone as well as in open arms of the elevated plus maze. Interestingly, capsaicin at different doses reversed the anxiety, depressive-like behaviors, and learning and memory impairment effects of scopolamine. Scopolamine-administered mice demonstrated substantially increased pro-inflammatory cytokines levels, impaired mitochondrial enzyme complex activities, and increased oxidative damage compared to the normal control group. Capsaicin treatment reinstated the reduced lipid peroxidation, nitric oxide, catalase, superoxide dismutase, reduced glutathione activity, decreasing pro-inflammatory cytokines and restoring mitochondrial complex enzyme activities (I, II, III, and IV) as well as mitochondrial permeability. Moreover, the IL-1β level was restored at a dose of capsaicin (10 and 20 mg/kg) only. Capsaicin reduced the scopolamine-induced acetylcholinesterase activity, thereby raising the acetylcholine concentration in the hippocampal tissues of mice. Preservation of neuronal cell morphology was also confirmed by capsaicin in histological studies. From the above experimental results, capsaicin at a dose of 10 mg/kg, p.o. for seven consecutive days was found to be the most effective dose.

CONCLUSION

The experiential neuroprotective effect of capsaicin through the restoration of mitochondrial functions, antioxidant effects, and modulation of pro-inflammatory cytokines makes it a promising candidate for further drug development through clinical setup.

Pharmacotherapy Evolution in Alzheimer's Disease: Current Framework and Relevant Directions

Alzheimer's disease (AD), once considered a rare disease, is now the most common form of dementia in the elderly population. Current drugs (cholinesterase inhibitors and glutamate antagonists) are safe but of limited benefit to most patients, offering symptomatic relief without successful cure of the disease. Since the last several decades, there has been a great need for the development of a treatment that might cure the underlying causes of AD and thereby slow its progression in vulnerable individuals. That is why phase I, II, and III studies that act on several fronts, such as cognitive improvement, symptom reduction, and enhancing the basic biology of AD, are imperative to stop the disease. This review discusses current treatment strategies, summarizing the clinical features and pharmacological properties, along with molecular docking analyses of the existing medications.

CADMA-Chem: A Computational Protocol Based on Chemical Properties Aimed to Design Multifunctional Antioxidants

A computational protocol aimed to design new antioxidants with versatile behavior is presented. It is called Computer-Assisted Design of Multifunctional Antioxidants and is based on chemical properties (CADMA-Chem). The desired multi-functionality consists of in different methods of antioxidant protection combined with neuroprotection, although the protocol can also be used to pursue other health benefits. The dM38 melatonin derivative is used as a study case to illustrate the protocol in detail. This was found to be a highly promising candidate for the treatment of neurodegeneration, in particular Parkinson's and Alzheimer's diseases. This also has the desired properties of an oral-drug, which is significantly better than Trolox for scavenging free radicals, and has chelates redox metals, prevents the ●OH production, via Fenton-like reactions, repairs oxidative damage in biomolecules (lipids, proteins, and DNA), and acts as a polygenic neuroprotector by inhibiting catechol-O-methyl transferase (COMT), acetylcholinesterase (AChE) and monoamine oxidase B (MAOB). To the best of our best knowledge, CADMA-Chem is currently the only protocol that simultaneously involves the analyses of drug-like behavior, toxicity, manufacturability, versatile antioxidant protection, and receptor-ligand binding affinities. It is expected to provide a starting point that helps to accelerate the discovery of oral drugs with the potential to prevent, or slow down, multifactorial human health disorders.

The Link between Oxidative Stress, Mitochondrial Dysfunction and Neuroinflammation in the Pathophysiology of Alzheimer's Disease: Therapeutic Implications and Future Perspectives

Alzheimer's disease (AD), the most common form of dementia, has increasing incidence, increasing mortality rates, and poses a huge burden on healthcare. None of the currently approved drugs for the treatment of AD influence disease progression. Many clinical trials aiming at inhibiting amyloid plaque formation, increasing amyloid beta clearance, or inhibiting neurofibrillary tangle pathology yielded inconclusive results or failed. Meanwhile, research has identified many interlinked vicious cascades implicating oxidative stress, mitochondrial dysfunction, and chronic neuroinflammation, and has pointed to novel therapeutic targets such as improving mitochondrial bioenergetics and quality control, diminishing oxidative stress, or modulating the neuroinflammatory pathways. Many novel molecules tested in vitro or in animal models have proven efficient, but their translation into clinic needs further research regarding appropriate doses, delivery routes, and possible side effects. Cell-based therapies and extracellular vesicle-mediated delivery of messenger RNAs and microRNAs seem also promising strategies allowing to target specific signaling pathways, but need further research regarding the most appropriate harvesting and culture methods as well as control of the possible tumorigenic side effects. The rapidly developing area of nanotechnology could improve drug delivery and also be used in early diagnosis.

Cross-sectional study of passive opiate smoking in relation to stroke and some of stroke attributable risk factors in women

Opiate use is related to neuropathological disorders, stroke and stroke attributable risk factors. However, secondary exposure to opiate in relation to the above-mentioned complications is studied only in animal models and remains to be evaluated in human populations. We tested whether passive exposure to opiate is associated with stroke and the known stroke predictive factors. We carried out a cross-sectional study of 1541 never smoker women who participated in the Rafsanjan Cohort Study (RCS) with their husbands (2015–2017 recruitment phase). RCS is one of the 19 geographic districts of the Prospective Epidemiological Research Studies in Iran (PERSIAN cohort study). Unadjusted and adjusted multiple logistic regression analyses were performed to evaluate the relationship between second-hand opiate exposure (husband opiate smoking after marriage) and the odds ratio of stroke and the following stroke risk factors and predictive parameters: overweight/obesity (BMI > 25), cholesterol (chol) > 200 mg/dl, fasting blood sugar (FBS) > 125 mg/dl, low density lipoprotein (LDL) > 100 mg/dl, triglyceride (TG) >  = 150 mg/dl, hypertension, diabetes, and chronic headache. We observed a significant increased adjusted odds ratio (OR) of stroke (OR = 3.43, 95% CI:1.33–8.82) and its risk factors LDL > 100 mg/dl (OR = 1.37, 95% CI:1.01–1.87) and FBS > 125 mg/dl (OR = 1.58, 95% CI:1.08–2.30) in women associated with husbands’ opiate smoking. This relationship was observed after adjusting for the confounding parameters including age, education years, and first-degree family history of the relevant diseases. The increased odds ratio for stroke and high LDL displayed a dose-sensitive trend with years of husband’s opiate smoking after marriage (respective p-trends: 0.02 & 0.01). We did not observe a significant association between passive opiate smoking and high TG, high Chol or the diseases diabetes, hypertension and chronic headache. However, 89% increased odds ratio of chronic headache was observed to be associated with passive opiate smoking for more than 10 years (OR = 1.89, 95% CI:1.02–3.50). We found an increased risk of stroke and high LDL and FBS in women associated with passive opiate smoking. Furthermore, a dose-sensitive connection was found between the risks of stroke, high LDL and chronic headache with the years of passive opiate exposure. Our results point to the necessity of the future analyses, which further assess whether passive opiate exposure could be considered as an independent risk factor for stroke and metabolic diseases.

The Status of Oxidative Stress in Patients with Alcohol Dependence: A Meta-Analysis

Alcohol-induced oxidative stress (OS) plays a pivotal role in the pathophysiology of alcohol dependence (AD). This meta-analysis was aimed at investigating the changes in the levels of OS biomarkers in AD patients. We included relevant literature published before 1 April 2022, from the PubMed, Web of Science, and EBSCO databases following PRISMA guidelines. Finally, 15 eligible articles were enrolled in this meta-analysis, including 860 patients and 849 controls. Compared with healthy controls, AD patients had lower activities of superoxide dismutase (SOD) and glutathione peroxidase (GPx) enzymes, and lower levels of albumin, while levels of malondialdehyde (MDA), vitamin B12, homocysteine, and bilirubin were significantly increased in serum/plasma samples of AD subjects (all p < 0.05). In male patients, the activities of SOD and GPx were increased in serum/plasma but decreased in erythrocytes (all p < 0.05). The opposite trends in the level of SOD and GPx activities in serum/plasma and erythrocytes of male patients could be used as the biomarker of alcohol-induced OS injury, and the synergistic changes of MDA, vitamin B12, albumin, bilirubin, and homocysteine levels should also be considered.

Recent Advances in the Neuroprotective Properties of Ferulic Acid in Alzheimer’s Disease: A Narrative Review

Alzheimer’s disease (AD) is a progressive degenerative disorder of the central nervous system, characterized by neuroinflammation, neurotransmitter deficits, and neurodegeneration, which finally leads to neuronal death. Emerging evidence highlighted that hyperglycemia and brain insulin resistance represent risk factors for AD development, thus suggesting the existence of an additional AD form, associated with glucose metabolism impairment, named type 3 diabetes. Owing to the limited pharmacological options, novel strategies, especially dietary approaches based on the consumption of polyphenols, have been addressed to prevent or, at least, slow down AD progression. Among polyphenols, ferulic acid is a hydroxycinnamic acid derivative, widely distributed in nature, especially in cereal bran and fruits, and known to be endowed with many bioactivities, especially antioxidant, anti-inflammatory and antidiabetic, thus suggesting it could be exploited as a possible novel neuroprotective strategy. Considering the importance of ferulic acid as a bioactive molecule and its widespread distribution in foods and medicinal plants, the aim of the present narrative review is to provide an overview on the existing preclinical and clinical evidence about the neuroprotective properties and mechanisms of action of ferulic acid, also focusing on its ability to modulate glucose homeostasis, in order to support a further therapeutic interest for AD and type 3 diabetes.

Analysis of occupational stress and its correlation with oxidative-antioxidant levels among employees of a power grid enterprise in Guangdong

BACKGROUND

Occupational stress and its health effects on occupational populations have attracted extensive attention from researchers in public health. The stressors faced by employees of power grid enterprises are increasing progressively, which is easy to cause occupational stress. The balance of the body's oxidative-antioxidant levels plays an essential role in maintaining the body's health status. This study aims to explore occupational stress and its correlation with oxidative-antioxidant levels in employees of a power grid enterprise.

METHODS

A cluster random sampling method was used to investigate the basic information of 528 employees in a power grid enterprise and investigate the two occupational stress models of employees by using the Job Content Questionnaire based on the job demand-control-support (JDC) model, and the Effort-Reward Imbalance Questionnaire based on the effort-reward imbalance (ERI) model, respectively. Peripheral blood samples were collected from the employees to measure the levels of malondialdehyde (MDA), total antioxidant capacity (TAC), and superoxide dismutase (SOD). The correlation between different models of occupational stress level and the body's oxidation-antioxidation level was further explored.

RESULTS

The detection rate of high JDC model occupational stress was 50.6% and the detection rate of high ERI model occupational stress was 50.9%. The JDC model occupational stress was significantly associated with high-temperature and high-altitude operation, visual display terminal operation, monthly income, and exercise (all P < 0.05). The ERI model occupational stress was significantly associated with visual display terminal operation (all P < 0.05). The results of the generalized additive model showed that SOD levels had a non-linear relationship with the D/C ratio as well as the E/R ratio. With the D/C ratio close to 1, SOD levels raised rapidly. When the E/R ratio exceeded 1, the SOD level raised rapidly (all P<0.05) . TAC levels were negatively associated with the E/R ratio (P < 0.05).

CONCLUSION

The detection rates of occupational stress in both models among employees in a power grid enterprise are higher. ERI model occupational stress was associated with body TAC and SOD levels, and JDC model occupational stress was associated with body SOD levels.

Sleep and affective disorders in relation to Parkinson's disease risk among older women from the Women's Health Initiative

OBJECTIVES

To evaluate sleep and affective (mood/anxiety) disorders as clinical predictors of incident Parkinson's disease (PD) among women ≥65 years of age.

METHODS

We performed secondary analyses with available data from the Women's Health Initiative Clinical Trials and Observational Study linked to Medicare claims. Sleep, mood and anxiety disorders at baseline were defined using diagnostic codes. Incident PD was defined using self-reported PD, first PD diagnosis, use of PD medications, and/or deaths attributed to PD. Cox regression was applied to estimate hazard ratios (HR) with 95 % confidence intervals (CI), controlling for socio-demographic/lifestyle/health characteristics. Time-to-event was calculated from baseline (1993-1998) to year of PD event, loss to follow-up, death, or December 31, 2018, whichever came first.

RESULTS

A total of 53,996 study-eligible WHI participants yielded 1756 (3.25 %) PD cases over ~14.39 (±6.18) years of follow-up. The relative risk for PD doubled among women with affective disorders (HR = 2.05, 95 % CI: 1.84, 2.27), mood disorders (HR = 2.18, 95 % CI: 1.97, 2.42) and anxiety disorders (HR = 1.97, 95 % CI: 1.75, 2.22). Sleep disorders alone (without affective) were not significantly associated with PD risk (HR = 0.85, 95 % CI: 0.69, 1.04), whereas affective disorders alone (without sleep) (HR = 1.93, 95 % CI: 1.72, 2.17) or in combination with sleep disorders (HR = 2.18, 95 % CI: 1.85, 2.56) were associated with twice the PD risk relative to no sleep/affective disorders.

LIMITATIONS

Observational design; Selection bias; Information bias; Generalizability.

CONCLUSIONS

Among older women, joint sleep/affective disorders and affective disorders alone are strong clinical predictors of incident PD over 14 years.

Rhus coriaria L. (Sumac), a Versatile and Resourceful Food Spice with Cornucopia of Polyphenols

In recent years, utilization of Rhus coriaria L. (sumac) is upgrading not only in their culinary use and human nutrition, but also in the pharmaceutical industry, food industry and veterinary practices. This is driven by accumulating evidence that support the ethnobotanical use of this plant; in particular, advanced knowledge of the content of nutritional, medicinal and techno-functional bioactive ingredients. Herein, we discuss polyphenolic compounds as the main bioactive ingredients in Rhus coriaria L., which contribute mainly to the significance and utility of this spice. Most of the antioxidant potential and therapeutic roles of sumac are increasingly attributed to its constituent tannins, flavonoids, and phenolic acids. Hydroxyphenyl pyranoanthocyanins and other anthocynins are responsible for the highly desired red pigments accounting for the strong pigmentation capacity and colorant ability of sumac. Certain polyphenols and the essential oil components are responsible for the peculiar flavor and antimicrobial activity of sumac. Tannin-rich sumac extracts and isolates are known to enhance the food quality and the oxidative stability of animal products such as meat and milk. In conclusion, polyphenol-rich sumac extracts and its bioactive ingredients could be exploited towards developing novel food products which do not only address the current consumers' interests regarding organoleptic and nutritional value of food, but also meet the growing need for 'clean label' as well as value addition with respect to antioxidant capacity, disease prevention, and health promotion in humans.

Salivary Testosterone and Cortisol Levels in Tunisian Elderly Male Patients With Mild Alzheimer’s Disease. Implications of Musical Therapy And/Or Physical Rehabilitation

Changes in salivary testosterone (T) and cortisol (C) levels were assessed in elderly Tunisian male patients with mild Alzheimer’s disease (AD) subjected to music therapy and/or physical rehabilitation. Male patients with mild AD (N = 26; age = 76.23 ± 4.27 years; weight: 74.76 ± 5.36 kg) were randomly assigned into four groups for three 60-min sessions per week for 4 months; including Group1 or control group (Co) (n = 6); Group2 (n = 6), participated in physical rehabilitation (PR); Group3 (n = 7), subjected to music therapy (MT) and Group4 (n = 7), participated simultaneously in music therapy and physical rehabilitation (MT + PR). Salivary T levels increased (ηp² = 0.7) and C levels decreased (ηp² = 0.69), significantly (p < 0.001) in the PR, MT and MT + PR groups compared to the Co group respectively. Also, increases in salivary T levels and decreases in C levels in MT + PR group were greater compared to the other groups. MT increased T levels (p < 0.001) and decreased C levels (p < 0.05) to a greater extent than the PR group respectively. Changes in salivary T levels were positively (r = 0.83; p < 0.001) and C levels were negatively (r = -0.86; p < 0.001) correlated in the PR, MT and MT + PR groups with changes in MMSE in AD patients. This study highlights that combination of MT and PR holds potential to treat AD.

Insights into the Explicit Protective Activity of Herbals in Management of Neurodegenerative and Cerebrovascular Disorders

The longstanding progressive neurodegenerative conditions of the central nervous system arise mainly due to deterioration, degradation and eventual neuronal cell loss. As an individual ages, the irreversible neurodegenerative disorders associated with aging also begin to develop, and these have become exceedingly prominent and pose a significant burden mentally, socially and economically on both the individual and their family. These disorders express several symptoms, such as tremors, dystonia, loss of cognitive functions, impairment of motor activity leading to immobility, loss of memory and many more which worsen with time. The treatment employed in management of these debilitating neurodegenerative disorders, such as Parkinson’s disease (which mainly involves the loss of dopaminergic neurons in the nigrostriatal region), Alzheimer’s disease (which arises due to accumulation of Tau proteins causing diffusive atrophy in the brain), Huntington’s disease (which involves damage of striatal and spinal neurons, etc.), have several adverse effects, leading to exploration of several lead targets and molecules existing in herbal drugs. The current review highlights the mechanistic role of natural products in the treatment of several neurodegenerative and cerebrovascular diseases such as Parkinson’s disease, Alzheimer’s disease, ischemic stroke and depression.

Psychotropic medication use and Parkinson's disease risk amongst older women

OBJECTIVE

To examine associations of antidepressant, anxiolytic and hypnotic use amongst older women (≥65 years) with incident Parkinson's Disease (PD), using data from Women's Health Initiative linked to Medicare claims.

METHODS

PD was defined using self-report, first diagnosis, medications and/or death certificates and psychotropic medications were ascertained at baseline and 3-year follow-up. Cox regression models were constructed to calculate adjusted hazard ratios (aHR) with 95% confidence intervals (CI), controlling for socio-demographic, lifestyle and health characteristics, overall and amongst women diagnosed with depression, anxiety and/or sleep disorders (DASD).

RESULTS

A total of 53,996 WHI participants (1,756 PD cases)-including 27,631 women diagnosed with DASD (1,137 PD cases)-were followed up for ~14 years. Use of hypnotics was not significantly associated with PD risk (aHR = 0.98, 95% CI: 0.82, 1.16), whereas PD risk was increased amongst users of antidepressants (aHR = 1.75, 95% CI: 1.56, 1.96) and anxiolytics (aHR = 1.48, 95% CI: 1.25, 1.73). Compared to non-users of psychotropic medications, those who used 1 type had ~50% higher PD risk, whereas those who used ≥2 types had ~150% higher PD risk. Women who experienced transitions in psychotropic medication use ('use to non-use' or 'non-use to use') between baseline and 3-year follow-up had higher PD risk than those who did not. We obtained similar results with propensity scoring and amongst DASD-diagnosed women.

INTERPRETATION

The use of antidepressants, anxiolytics or multiple psychotropic medication types and transitions in psychotropic medication use was associated with increased PD risk, whereas the use of hypnotics was not associated with PD risk amongst older women.

Levetiracetam Mechanisms of Action: From Molecules to Systems

Epilepsy is a chronic disease that affects millions of people worldwide. Antiepileptic drugs (AEDs) are used to control seizures. Even though parts of their mechanisms of action are known, there are still components that need to be studied. Therefore, the search for novel drugs, new molecular targets, and a better understanding of the mechanisms of action of existing drugs is still crucial. Levetiracetam (LEV) is an AED that has been shown to be effective in seizure control and is well-tolerable, with a novel mechanism of action through an interaction with the synaptic vesicle protein 2A (SV2A). Moreover, LEV has other molecular targets that involve calcium homeostasis, the GABAergic system, and AMPA receptors among others, that might be integrated into a single mechanism of action that could explain the antiepileptogenic, anti-inflammatory, neuroprotective, and antioxidant properties of LEV. This puts it as a possible multitarget drug with clinical applications other than for epilepsy. According to the above, the objective of this work was to carry out a comprehensive and integrative review of LEV in relation to its clinical uses, structural properties, therapeutical targets, and different molecular, genetic, and systemic action mechanisms in order to consider LEV as a candidate for drug repurposing.

Polysaccharide-based electroconductive hydrogels: Structure, properties and biomedical applications

Architecting an appropriate platform for biomedical applications requires setting a balance between simplicity and complexity. Polysaccharides (PSAs) play essential roles in our life in food resources, structural materials, and energy storage capacitors. Moreover, the diversity and abundance of PSAs have made them an indispensable part of food ingredients and cosmetics. PSA-based hydrogels have been extensively reviewed in biomedical applications. These hydrogels can be designed in different forms to show optimum performance. For instance, electroactive PSA-based hydrogels respond under an electric stimulus. Such performance can be served in stimulus drug release and determining cell fate. This review classifies and discusses the structure, properties, and applications of the most important polysaccharide-based electroactive hydrogels (agarose, alginate, chitosan, cellulose, and dextran) in medicine, focusing on their usage in tissue engineering, flexible electronics, and drug delivery applications.

Cross-Talk between Amyloid, Tau Protein and Free Radicals in Post-Ischemic Brain Neurodegeneration in the Form of Alzheimer’s Disease Proteinopathy

Recent years have seen remarkable progress in research into free radicals oxidative stress, particularly in the context of post-ischemic recirculation brain injury. Oxidative stress in post-ischemic tissues violates the integrity of the genome, causing DNA damage, death of neuronal, glial and vascular cells, and impaired neurological outcome after brain ischemia. Indeed, it is now known that DNA damage and repair play a key role in post-stroke white and gray matter remodeling, and restoring the integrity of the blood-brain barrier. This review will present one of the newly characterized mechanisms that emerged with genomic and proteomic development that led to brain ischemia to a new level of post-ischemic neuropathological mechanisms, such as the presence of amyloid plaques and the development of neurofibrillary tangles, which further exacerbate oxidative stress. Finally, we hypothesize that modified amyloid and the tau protein, along with the oxidative stress generated, are new key elements in the vicious circle important in the development of post-ischemic neurodegeneration in a type of Alzheimer’s disease proteinopathy.

Acacia catechu Willd. Extract Protects Neuronal Cells from Oxidative Stress-Induced Damage

Oxidative stress (OS) and the resulting reactive oxygen species (ROS) generation and inflammation play a pivotal role in the neuronal loss occurring during the onset of neurodegenerative diseases. Therefore, promising future drugs that would prevent or slow down the progression of neurodegeneration should possess potent radical-scavenging activity. Acacia catechu Willd. heartwood extract (AC), already characterized for its high catechin content, is endowed with antioxidant properties. The aim of the present study was to assess AC neuroprotection in both human neuroblastoma SH-SY5Y cells and rat brain slices treated with hydrogen peroxide. In SH-SY5Y cells, AC prevented a decrease in viability, as well as an increase in sub-diploid-, DAPI positive cells, reduced ROS formation, and recovered the mitochondrial potential and caspase-3 activation. AC related neuroprotective effects also occurred in rat brain slices as a reversal prevention in the expression of the main proteins involved in apoptosis and signalling pathways related to calcium homeostasis following OS-mediated injury. Additionally, unbiased quantitative mass spectrometry allowed for assessing that AC partially prevented the hydrogen peroxide-induced altered proteome, including proteins belonging to the synaptic vesicle fusion apparatus. In conclusion, the present results suggest the possibility of AC as a nutraceutical useful in preventing neurodegenerative diseases.

Moringa oleifera: A Tree of Life as a Promising Medicinal Plant for Neurodegenerative Diseases

Moringa oleifera, popularly known as a miracle tree or tree of life, has been extensively used as a functional food and nutritional asset worldwide. Ethnomedicinal and traditional uses of M. oleifera indicate that this plant might have a pleiotropic therapeutic efficacy against most human ailments. In fact, M. oleifera is reported to have several pharmacological activities, including antioxidant, antibacterial, antifungal, antidiabetic, antipyretic, antiulcer, antispasmodic, antihypertensive, antitumor, hepatoprotective, and cardiac stimulant properties. Recently, a few experimental studies reported the neuroprotective effects of M. oleifera against Alzheimer's disease, dementia, Parkinson's disease, stroke, and neurotoxicity-related symptoms. In addition, several neuroprotective phytochemicals have been isolated from M. oleifera, which signifies that it can have promising neuroprotective effects. Therefore, this review aimed to explore the current updates and future prospective of neuroprotective efficacies of M. oleifera.

Curcumin Ameliorates the Cd-Induced Anxiety-like Behavior in Mice by Regulating Oxidative Stress and Neuro-Inflammatory Proteins in the Prefrontal Cortex Region of the Brain

Age-related neurodegenerative diseases and vascular dementia are major challenges to the modern health care system. Most neurodegenerative diseases are associated with impaired spatial working memory and anxiety-like behavior. Thus, it is important to understand the underlying cellular mechanisms of neurodegenerative diseases in different regions of the brain to develop an effective therapeutic approach. In our previous research paper, we have reported the ameliorative effect of curcumin in Cd-induced hippocampal neurodegeneration. However, recently many researchers had reported the important role of the prefrontal cortex in higher cognitive functions. Therefore, to look into the cellular mechanism of curcumin protection against Cd-induced prefrontal cortex neurotoxicity, we investigated spatial working memory, anxiety-like behavior and analyzed prefrontal cortex inflammatory markers (IL-6, IL-10, and TNFα), antioxidant enzymes (SOD, GSH, and CAT), and pro-oxidant MDA level. Further, we conducted histological studies of the prefrontal cortex in Swiss albino mice exposed to cadmium (2.5 mg/kg). We observed that curcumin treatment improved the spatial working memory and anxiety-like behavior of mice through reduction of prefrontal cortex neuroinflammation and oxidative stress as well as increasing the number of viable prefrontal cortex neuronal cells. Our result suggests that environmental heavy metal cadmium can induce behavioral impairment in mice through prefrontal cortex cellular inflammation and oxidative stress. We found that curcumin has a potential therapeutic property to mitigate these behavioral and biochemical impairments induced by cadmium.

Anti-Oxidative, Anti-Inflammatory and Anti-Apoptotic Effects of Flavonols: Targeting Nrf2, NF-κB and p53 Pathways in Neurodegeneration

Neurodegenerative diseases are one of the leading causes of disability and death worldwide. Intracellular transduction pathways that end in the activation of specific transcription factors are highly implicated in the onset and progression of pathological changes related to neurodegeneration, of which those related to oxidative stress (OS) and neuroinflammation are particularly important. Here, we provide a brief overview of the key concepts related to OS- and neuroinflammation-mediated neuropathological changes in neurodegeneration, together with the role of transcription factors nuclear factor erythroid 2-related factor 2 (Nrf2) and nuclear factor-κB (NF-κB). This review is focused on the transcription factor p53 that coordinates the cellular response to diverse genotoxic stimuli, determining neuronal death or survival. As current pharmacological options in the treatment of neurodegenerative disease are only symptomatic, many research efforts are aimed at uncovering efficient disease-modifying agents. Natural polyphenolic compounds demonstrate powerful anti-oxidative, anti-inflammatory and anti-apoptotic effects, partially acting as modulators of signaling pathways. Herein, we review the current understanding of the therapeutic potential and limitations of flavonols in neuroprotection, with emphasis on their anti-oxidative, anti-inflammatory and anti-apoptotic effects along the Nrf2, NF-κB and p53 pathways. A better understanding of cellular and molecular mechanisms of their action may pave the way toward new treatments.