Allicin ameliorates aluminium- and copper-induced cognitive dysfunction in Wistar rats: relevance to neuro-inflammation, neurotransmitters and Aβ(1-42) analysis

The Effect of Trientine on AlCl3-Induced Cognitive Dysfunction and Biochemical Changes in the Hippocampus of Rats

Cognitive impairments affect millions of people worldwide with an increasing prevalence. Research on their etiology and treatment is developing, nevertheless significant gaps remain. Trientine (TETA), as a copper chelator, has been shown to have beneficial effects in different human chronic diseases such as diabetic cardiomyopathy and neuropathy. Here, we examined the impact of TETA on AlCl3-induced neurocognitive dysfunctions and molecular changes in the hippocampus of rats.Thirty-six male Wistar rats (weighing 200-250 g) were randomly divided into four groups including control, TETA (100 mg/kg/day), AlCl3 (100 mg/kg/day), and AlCl3 (100 mg/kg/day)+TETA (100 mg/kg/day), and received chemicals by gavage for 30 days. At the end of the treatment, the open field maze, elevated plus maze, novel object recognition memory test, and shuttle box test were done. Then after, brain-derived neurotrophic factor (BDNF), glycogen synthase kinase-3 β (GSK-3β), acetylcholinesterase activity, oxidative stress markers, and inflammatory mediators were measured in the hippocampus.AlCl3 increased anxiety-like behaviors and impaired recognition and short-term memory. TETA was able to improve AlCl3-induced anxiety-like behaviors and short-term memory dysfunction. In the AlCl3-treated group, there was a significant increase in GSK-3β, oxidative stress, pro-inflammatory and pro-apoptotic markers, and decreased BDNF in the hippocampus. Co-administration of TETA was able to decrease lipid peroxidation, inflammation, GSK-3β, and acetylcholinesterase activity, and increase BDNF in the hippocampus compared with AlCl3-treated rats.It can be concluded that TETA was able to improve neurobehavioral and neurocognitive functions by alleviating oxidative stress, inflammation, and pro-apoptotic pathways leading to the normalization of BDNF and GSK-3β.

Effect of Salvia officinalis aqueous infusion on copper sulfate-induced inflammatory response and oxidative stress imbalance in mice liver and kidney

Extracts of Salvia officinalis (S. officinalis) have been described to have many therapeutic properties. However, the effect of S. officinalis on copper sulfate toxicity has not been previously reported. The aim of this study was to investigate the toxicity of copper sulfate and the potential beneficial effects of S. officinalis aqueous infusion on proinflammatory response and antioxidant status. 56 male mice were used and equally divided into 6 groups: control group, copper sulfate treated group (40 mg/kg), S. officinalis aqueous infusion treated groups (200 mg/kg and 400 mg/kg) separately or in combination with copper. IL-6 (interleukine-6) and TNF-α (Tumor necrosis factor alpha) were assessed by Elisa. Catalase (CAT), superoxide dismutase (SOD) and acetylcholinesterase (AChE) activities, malondialdehyde (MDA) and oxygen peroxide levels were determined. Serum biochemical parameters were analyzed. Copper enhanced aspartate aminotransferase (AST), alanine aminotransferase (ALT) and Lactate dehydrogenase (LDH) (p < 0.05). Copper enhances significantly IL-6, TNF-α and MDA levels in liver and kidney and reduced CAT, SOD and AChE activities (p < 0.05). Aqueous infusion of S. officinalis at 400 mg/kg abolished copper-induced changes in AST and ALT activity. S. officinalis aqueous infusion at 200 mg/kg reversed copper-induced IL-6 in kidney and TNF-α in liver at both doses. S. officinalis aqueous infusion at 400 mg/kg restored SOD in kidney and CAT and AChE activities in both liver and kidney. S. officinalis aqueous infusion may be useful in partially ameliorating tissue disorders induced by copper exposure such as inflammatory response, oxidative stress imbalance and organ dysfunction through its phenolic compounds and higher antioxidant capacity.

Coenzyme Q10 ameliorates chemotherapy-induced cognitive impairment in mice: a preclinical study

BACKGROUND

Among the three most used anticancer drugs, cyclophosphamide, Adriamycin, and 5-Fluorouracil (CAF), the most significant outcome is chemobrain, caused by increased oxidative stress, inflammatory insult, and mitochondrial dysfunction.

OBJECTIVE

In this study, endogenous antioxidant coenzyme Q10 (CoQ10) was evaluated for its neuroprotective effects in CICI.

MATERIALS AND METHODS

The chemobrain was induced in Swiss albino female mice by administering CAF (40 + 4 + 25 mg/kg) intraperitoneal (i.p.) in three cycles (single injection per week) followed by treatment with CoQ10 (40 mg/kg; p.o.) for up to 3 weeks followed by behavioral, biochemical, molecular and histopathological analysis.

RESULTS

Treatment with CoQ10 significantly improved cognition by improving exploring time in novel objects recognition test followed by increasing the time spent in the target quadrant in MWM test as compared to CAF-treated animals. Moreover, CoQ10 demonstrated antioxidant properties by reducing the expression of LPO while increasing levels of GSH, SOD, and catalase as compared to CAF-treated animals. While the levels of AChEs were significantly reduced after CoQ10 treatment in CAF-treated animals. In terms of its mechanism, it effectively counteracted the pro-inflammatory substances (TNF-α and IL-1β) triggered by CAF while also enhancing the levels of anti-inflammatory markers (IL-10 and Nrf2). Moreover, CoQ10 showed mitochondrial enhancers and it improved the level of Complex (I, II, and IV). Besides that, mitochondrial morphological analysis was done by TEM, and neuronal morphology along with quantification analysis was performed by H&E staining using Image J software to confirm the neuroprotective effect of CoQ10 over CAF-induced cognitive impairment.

CONCLUSION

This study suggests CoQ10 can protect the mitochondria by imposing antioxidant, and anti-inflammatory properties, which could be a potential therapy for CICI.

Environmental Toxins and Alzheimer's Disease: a Comprehensive Analysis of Pathogenic Mechanisms and Therapeutic Modulation

Alzheimer's disease is a leading cause of mortality worldwide. Inorganic and organic hazards, susceptibility to harmful metals, pesticides, agrochemicals, and air pollution are major environmental concerns. As merely 5% of AD cases are directly inherited indicating that these environmental factors play a major role in disease development. Long-term exposure to environmental toxins is believed to progress neuropathology, which leads to the development of AD. Numerous in-vitro and in-vivo studies have suggested the harmful impact of environmental toxins at cellular and molecular level. Common mechanisms involved in the toxicity of these environmental pollutants include oxidative stress, neuroinflammation, mitochondrial dysfunction, abnormal tau, and APP processing. Increased expression of GSK-3β, BACE-1, TNF-α, and pro-apoptotic molecules like caspases is observed upon exposure to these environmental toxins. In addition, the expression of neurotrophins like BDNF and GAP-43 have been found to be reduced as a result of toxicity. Further, modulation of signaling pathways involving PARP-1, PGC-1α, and MAPK/ERK induced by toxins have been reported to contribute in AD pathogenesis. These pathways are a promising target for developing novel AD therapeutics. Drugs like epigallocatechin-gallate, neflamapimod, salsalate, dexmedetomidine, and atabecestat are in different phases of clinical trials targeting the pathways for possible treatment of AD. This review aims to culminate the correlation between environmental toxicants and AD development. We emphasized upon the signaling pathways involved in the progression of the disease and the therapeutics under clinical trial targeting the altered pathways for possible treatment of AD.

Naringenin mitigates aluminum toxicity-induced learning memory impairments and neurodegeneration through amelioration of oxidative stress

Aluminum chloride (AlCl3) is a potent neurotoxic substance known to cause memory impairment and oxidative stress-dependent neurodegeneration. Naringenin (NAR) is a dietary flavonoid with potent antioxidant and anti-inflammatory properties which was implemented against AlCl3-induced neurotoxicity to ascertain its neuroprotective efficacy. Experimental neurotoxicity in mice was induced by exposure of AlCl3 (10 mg/kg, p.o.) followed by treatment with NAR (10 mg/kg, p.o.) for a total of 63 days. Assessed the morphometric, learning memory dysfunction (novel object recognition, T- and Y-maze tests), neuronal oxidative stress, and histopathological alteration in different regions of the brain, mainly cortex, hippocampus, thalamus, and cerebellum. AlCl3 significantly suppressed the spatial learning and memory power which were notably improved by administration of NAR. The levels of oxidative stress parameters nitric oxide, advanced oxidation of protein products, protein carbonylation, lipid peroxidation, superoxide dismutase, catalase, glutathione reductase, reduced glutathione, and the activity of acetylcholine esterase were altered 1.5-3 folds by AlCl3 significantly. Treatment of NAR remarkably restored the level of oxidative stress parameters and maintained the antioxidant defense system. AlCl3 suppressed the expression of neuronal proliferation marker NeuN that was restored by NAR treatment which may be a plausible mechanism. NAR showed therapeutic efficacy as a natural supplement against aluminum-intoxicated memory impairments and histopathological alteration through a mechanism involving an antioxidant defense system and neuronal proliferation.

Moringa oleifera leaves ethanolic extract counteracts cortical neurodegeneration induced by aluminum chloride in rats

Background

Aluminum, a well-recognized neurotoxin, is implicated in various neurodegenerative disorders. Moringa oleifera (M. oleifera), known as a miracle tree, is utilized as a functional food and nutritional supplement. This study investigates the potential preventive effects of M. oleifera extract on aluminum chloride (AlCl3)-induced cortical neurodegeneration in rats.

Materials and methods

Therefore, 24 adult male Wistar rats were randomly divided into four distinct groups: negative control, M. oleifera extract (MOE), AlCl3, and AlCl3 + MOE. Treatments were administered orally for 28 consecutive days. Cognitive performance, brain oxidative/nitrosative stress, neuroinflammation, apoptotic-cell death, and associated histopathological alterations were assessed.

Results

Our results showed that MOE improved spatial learning and memory, enhanced antioxidant superoxide dismutase enzyme activity, antagonized nitrosative stress, reduced inflammatory cytokines (tumor necrosis factor-alpha and interleukin-6), decreased caspase-3, increased Bcl-2, and facilitated repair of cortical and hippocampal structures.

Conclusions

We concluded that MOE exhibits protective effects against cortical neurodegeneration, making it a promising supplement to counteract aluminum-induced neurotoxic effects.

Fucoxanthin mitigates valproic acid-induced autistic behavior through modulation of the AKT/GSK-3β signaling pathway

This study aimed to investigate the effects of fucoxanthin, a natural compound found in seaweed, on various aspects of autism using a rat model induced by valproic acid (VPA). Pregnant rats were administered VPA (600 mg/kg) on gestational day 12.5, and male pups were orally administered fucoxanthin at 50, 100, or 200 mg/kg beginning on post-natal day (PND) 23-43. Behavioral assessments were conducted on PND 45-53, and on PND 54, the animals were sacrificed for further biochemical analyses (superoxide dismutase (SOD) and glutathione (GSH), nitric oxide (NO)) via UV spectroscopy. Inflammatory markers (IL-17, TNF-α, and IL-1β) were also analyzed by sandwich ELISA, and the molecular parameters were evaluated through ELISA. The results revealed that, compared with VPA, fucoxanthin improved behavior and neuronal morphology. Specifically, fucoxanthin administration was found to enhance spatial memory, reduce pain sensitivity, and improve social interaction, locomotor activity, balance, and motor coordination. Fucoxanthin also exhibited anti-inflammatory and antioxidant effects, as indicated by the restoration of SOD and GSH levels and reduced inflammatory cytokine levels. Molecular analyses revealed that fucoxanthin restored the levels of GSK-3β and AKT. Furthermore, fucoxanthin regulates neurotransmitters, which are related to increasing GABA and reducing glutamate levels in the cortex and cerebellum. The therapeutic effects were dose-dependent, with higher doses (200 mg/kg) showing greater efficacy than lower doses (100 mg/kg) in improving behavioral, biochemical, neurotransmitter, and molecular parameters. Fucoxanthin is a potential treatment for autism, but further research, including clinical trials, is necessary to determine its effectiveness in humans.

Are high copper levels related to Alzheimer's and Parkinson's diseases? A systematic review and meta-analysis of articles published between 2011 and 2022

Copper performs an important role in the brain, but in high levels it can be neurotoxic. Further, some authors have described that copper dyshomeostasis could be related with neurodegenerative diseases. Thus, this review was performed to observe whether high copper levels are related to Alzheimer's and Parkinson's diseases (AD and PD), using the literature published recently. Articles that measured copper levels in AD or PD patients was included, as well as they that measured copper levels in models used to mimic these diseases. Also, results about high copper levels effects and its relationship with AD and PD observed in laboratory animals are considered. In summary, 38 and 24 articles with AD and PD patients were included, respectively. Despite of the heterogeneity between the studies in humans, meta-analysis has demonstrated that there is an increase in free and total copper levels in the blood of AD patients compared to controls, and a decrease in copper levels in PD patients. A decrease in the metal content in postmortem brain tissue was observed in AD and PD. In manuscripts using animal models that mimic AD and PD, it was included seven and three articles, respectively. Two of them have reported an increase in copper concentrations in AD model, and one in PD model. Finally, studies with laboratory animals have concluded that high copper levels are related to oxidative stress, neuroinflammation, mitochondrial dysfunction, changes in neurotransmitter levels, cell death, and reduced both cognitive and locomotor activity, which are also described in AD or PD.

A review on metal complexes and its anti-cancer activities: Recent updates from in vivo studies

Research into cancer therapeutics has uncovered various potential medications based on metal-containing scaffolds after the discovery and clinical applications of cisplatin as an anti-cancer agent. This has resulted in many metallodrugs that can be put into medical applications. These metallodrugs have a wider variety of functions and mechanisms of action than pure organic molecules. Although platinum-based medicines are very efficient anti-cancer agents, they are often accompanied by significant side effects and toxicity and are limited by resistance. Some of the most studied and developed alternatives to platinum-based anti-cancer medications include metallodrugs based on ruthenium, gold, copper, iridium, and osmium, which showed effectiveness against many cancer cell lines. These metal-based medicines represent an exciting new category of potential cancer treatments and sparked a renewed interest in the search for effective anti-cancer therapies. Despite the widespread development of metal complexes touted as powerful and promising in vitro anti-cancer therapeutics, only a small percentage of these compounds have shown their worth in vivo models. Metallodrugs, which are more effective and less toxic than platinum-based drugs and can treat drug-resistant cancer cells, are the focus of this review. Here, we highlighted some of the most recently developed Pt, Ru, Au, Cu, Ir, and Os complexes that have shown significant in vivo antitumor properties between 2017 and 2023.

Copper and cuproptosis: new therapeutic approaches for Alzheimer's disease

Copper (Cu) plays a crucial role as a trace element in various physiological processes in humans. Nonetheless, free copper ions accumulate in the brain over time, resulting in a range of pathological changes. Compelling evidence indicates that excessive free copper deposition contributes to cognitive decline in individuals with Alzheimer's disease (AD). Free copper levels in the serum and brain of AD patients are notably elevated, leading to reduced antioxidant defenses and mitochondrial dysfunction. Moreover, free copper accumulation triggers a specific form of cell death, namely copper-dependent cell death (cuproptosis). This article aimed to review the correlation between copper dysregulation and the pathogenesis of AD, along with the primary pathways regulating copper homoeostasis and copper-induced death in AD. Additionally, the efficacy and safety of natural and synthetic agents, including copper chelators, lipid peroxidation inhibitors, and antioxidants, were examined. These treatments can restore copper equilibrium and prevent copper-induced cell death in AD cases. Another aim of this review was to highlight the significance of copper dysregulation and promote the development of pharmaceutical interventions to address it.

Bioavailability, Health Benefits, and Delivery Systems of Allicin: A Review

Garlic has been used worldwide as a spice due to its pungent taste and flavor-enhancing properties. As a main biologically active component of the freshly crushed garlic extracts, allicin (diallyl thiosulfinate) is converted from alliin by alliinase upon damaging the garlic clove, which has been reported to have many potent beneficial biological functions. In this work, allicin formation, stability, bioavailability, and metabolism process are examined and summarized. The biological functions of allicin and potential underlying mechanisms are reviewed and discussed, including antioxidation, anti-inflammation, antidiabetic, cardioprotective, antineurodegenerative, antitumor, and antiobesity effects. Novel delivery systems of allicin with enhanced stability, encapsulation efficiency, and bioavailability are also evaluated, such as nanoparticles, gels, liposomes, and micelles. This study could provide a comprehensive understanding of the physiochemical properties and health benefits of allicin, with great potential for further applications in the food and nutraceutical industries.

Therapeutic effect of allicin in a mouse model of intracerebral hemorrhage

Natural compounds with sulfur moiety produce various biological actions that may be beneficial for the therapies of several devastative disorders of the central nervous system. Here we investigated potential therapeutic effect of allicin, an organosulfur compound derived from garlic, in a mouse model of intracerebral hemorrhage (ICH) based on intrastriatal collagenase injection. Daily intraperitoneal administration of allicin (50 mg/kg) from 3 h after induction of ICH afforded neuroprotective effects, as evidenced by the increase of surviving neurons in the hematoma, reduction of axonal transport impairment, and prevention of axon tract injury. In addition, allicin inhibited accumulation of activated microglia/macrophages around the hematoma and infiltration of neutrophils within the hematoma. Allicin also suppressed ICH-induced mRNA upregulation of pro-inflammatory factors such as interleukin 6 and C-X-C motif ligand 2 in the brain, suggesting its anti-inflammatory effect. Moreover, ICH-induced increase of malondialdehyde as well as decrease of total glutathione in the brain was attenuated by allicin. Finally, allicin-treated mice showed better recovery of sensorimotor functions after ICH than vehicle-treated mice. These results indicate that allicin produces a therapeutic effect on ICH pathology via alleviation of neuronal damage, inflammatory responses and oxidative stress in the brain.

Cladribine induces apoptosis, neuroinflammation, mitochondrial oxidative stress, tau phosphorylation and Aβ (1-42) pathway in the hippocampus: An in vivo approach

Cladribine is a purine nucleoside found to enhance toxic amyloid protein and cause memory impairment. Patients following chemotherapy treatment commonly suffer from cognitive deficits more prevalent in the elderly than adults. A previous research study revealed that cladribine has a high affinity to the brain, increases the level of amyloid precursor protein, and results in learning deficits. The study was designed to validate an animal model of cladribine administration to rats through mitochondrial oxidative stress, inflammation, apoptosis, tau phosphorylation, and amyloid-β (1-42) accumulation. In this study, all rats were orally given cladribine (0.5 and 1 mg/kg) for 28 days, resulting in impaired spatial memory confirmed by behavioural activity. On day 29, all rats were euthanized, and the hippocampal tissues were isolated and used for the estimation of neuroinflammatory markers, biochemicals parameters (glutathione, catalase, lipid peroxidation, and nitrite), amyloid-β (1-42) level, neurotransmitters, and nuclear factor kappa B analysis. Cladribine administration significantly elevated cytokines release, dysbalanced neurotransmitter concentration, and promoted the Aβ accumulation and hyperphosphorylation of tau protein. Our study outcome confirmed that cladribine produces cognitive impairment via activation of Nuclear factor kappa B, mitochondrial oxidative stress and dysbalanced of the endogenous antioxidant defence system.

Does Inflammation Play a Major Role in the Pathogenesis of Alzheimer's Disease?

Alzheimer's disease (AD) is a neurodegenerative disease leading to dementia for which no effective medicine exists. Currently, the goal of therapy is only to slow down the inevitable progression of the disease and reduce some symptoms. AD causes the accumulation of proteins with the pathological structure of Aβ and tau and the induction of inflammation of nerves in the brain, which lead to the death of neurons. The activated microglial cells produce pro-inflammatory cytokines that induce a chronic inflammatory response and mediate synapse damage and the neuronal death. Neuroinflammation has been an often ignored aspect of ongoing AD research. There are more and more scientific papers taking into account the aspect of neuroinflammation in the pathogenesis of AD, although there are no unambiguous results regarding the impact of comorbidities or gender differences. This publication concerns a critical look at the role of inflammation in the progression of AD, based on the results of our own in vitro studies using model cell cultures and other researchers.

Pharmacological Inhibition of Ferroptosis as a Therapeutic Target for Neurodegenerative Diseases and Strokes

Emerging evidence suggests that ferroptosis, a unique regulated cell death modality that is morphologically and mechanistically different from other forms of cell death, plays a vital role in the pathophysiological process of neurodegenerative diseases, and strokes. Accumulating evidence supports ferroptosis as a critical factor of neurodegenerative diseases and strokes, and pharmacological inhibition of ferroptosis as a therapeutic target for these diseases. In this review article, the core mechanisms of ferroptosis are overviewed and the roles of ferroptosis in neurodegenerative diseases and strokes are described. Finally, the emerging findings in treating neurodegenerative diseases and strokes through pharmacological inhibition of ferroptosis are described. This review demonstrates that pharmacological inhibition of ferroptosis by bioactive small-molecule compounds (ferroptosis inhibitors) could be effective for treatments of these diseases, and highlights a potential promising therapeutic avenue that could be used to prevent neurodegenerative diseases and strokes. This review article will shed light on developing novel therapeutic regimens by pharmacological inhibition of ferroptosis to slow down the progression of these diseases in the future.

Exploring the Link between Chronic Kidney Disease and Alzheimer's Disease: A Longitudinal Follow-Up Study Using the Korean National Health Screening Cohort

Chronic kidney disease (CKD) and Alzheimer's disease (AD) are common chronic diseases in the elderly population. Although a relationship between CKD and the occurrence of AD has been proposed, previous research results have been disputed, and further investigation is necessary to confirm this relationship. In this longitudinal follow-up study, we examined data from the Korean National Health Insurance Service-Health Screening Cohort, consisting of 15,756 individuals with CKD and 63,024 matched controls aged ≥40 years who received health check-ups between 2002 and 2019. Overlap-weighted Cox proportional hazard regression models were exploited to calculate hazard ratios (HRs) for the association between CKD and AD. During the monitoring period, individuals with CKD had a greater incidence of AD than those without CKD (15.80 versus 12.40 per 1000 person years). After accounting for various factors, CKD was significantly associated with a 1.14-fold increased likelihood of developing AD, with a 95% confidence interval ranging from 1.08 to 1.20. In subgroup analysis, this relationship persisted irrespective of age (≥70 or <70), sex, income, smoking status, alcohol consumption, place of residence, or fasting blood glucose level. Additionally, the association between CKD and AD was still evident among patients who were overweight or obese, those with normal blood pressure or cholesterol levels, and those without any other health conditions or with a CCI score of ≥2. These results suggest that CKD could increase the probability of developing AD in the Korean adult population irrespective of demographic or lifestyle conditions. This may make it challenging to predict AD in patients with CKD, emphasizing the importance of frequent AD screening and management.

Effect and mechanism of acupuncture on Alzheimer's disease: A review

With the development trend of an aging society, Alzheimer's disease (AD) has become an urgent problem in the field of medicine worldwide. Cognitive impairment in AD patients leads to a decline in the ability to perform daily living and abnormalities in behavior and personality, causing abnormal psychiatric symptoms, which seriously affect the daily life of patients. Currently, mainly drug therapy is used for AD patients in the clinic, but a large proportion of patients will experience drug efficacy not working, and even some drugs bring severe sleep disorders. Acupuncture, with its unique concept and treatment method, has been validated through a large number of experiments and proved its reliability of acupuncture in the treatment of AD. Many advances have been made in the study of the neurobiological mechanisms of acupuncture in the treatment of AD, further demonstrating the good efficacy and unique advantages of acupuncture in the treatment of AD. This review first summarizes the pathogenesis of AD and then illustrates the research progress of acupuncture in the treatment of AD, which includes the effect of acupuncture on the changes of biochemical indicators in AD in vivo and the specific mechanism of action to exert the therapeutic effect. Changes in relevant indicators of AD similarly further validate the effectiveness of acupuncture treatment. The clinical and mechanistic studies of acupuncture in the treatment of AD are intensified to fit the need for social development. It is believed that acupuncture will achieve new achievements in the treatment of AD as research progresses.

Neuroprotective efficacy of the bacterial metabolite, prodigiosin, against aluminium chloride-induced neurochemical alternations associated with Alzheimer's disease murine model: Involvement of Nrf2/HO-1/NF-κB signaling

Prodigiosin (PDG) is a bacterial metabolite with numerous biological and pharmaceutical properties. Exposure to aluminium is considered a root etiological factor in the pathological progress of Alzheimer's disease (AD). Here, in this investigation, we explored the neuroprotective potential of PDG against aluminium chloride (AlCl₃ )-mediated AD-like neurological alterations in rats. For this purpose, rats were gavaged either AlCl₃ (100 mg/kg), PDG (300 mg/kg), or both for 42 days. As a result of the analyzes performed on the hippocampal tissue, it was observed that AlCl₃ induced biochemical, molecular, and histopathological changes like those related to AD. PDG pre-treatment significantly decreased acetylcholinesterase activity and restored the levels of brain-derived neurotrophic factor, monoamines (dopamine, norepinephrine, and serotonin), and transmembrane protein (Na⁺ /K⁺ -ATPase). Furthermore, PDG boosted the hippocampal antioxidant capacity, as shown by the increased superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, and glutathione contents. These findings were accompanied by decreases in malondialdehyde and nitric oxide levels. The antioxidant effect may promote the upregulation of the expression of antioxidant genes (Nrf2 and HO-1). Moreover, PDG exerted notable anti-inflammatory effects via the lessening of interleukin-1 beta, tumor necrosis factor-alpha, cyclooxygenase-2, nuclear factor kappa B, and decreases in the gene expression of inducible nitric oxide synthase. In addition, noteworthy decreases in pro-apoptotic (Bax and caspase-3) levels and increases in anti-apoptotic (Bcl-2) biomarkers suggested an anti-apoptotic effect of PDG. In support, the hippocampal histological examination validated the aforementioned changes. To summarize, the promising neuromodulatory, antioxidative, anti-inflammatory, and anti-apoptotic activities of PDG establish it as a potent therapeutic option for AD.

Novel insights into the immune cell landscape and gene signatures in autism spectrum disorder by bioinformatics and clinical analysis

The pathogenesis of autism spectrum disorder (ASD) is not well understood, especially in terms of immunity and inflammation, and there are currently no early diagnostic or treatment methods. In this study, we obtained six existing Gene Expression Omnibus transcriptome datasets from the blood of ASD patients. We performed functional enrichment analysis, PPI analysis, CIBERSORT algorithm, and Spearman correlation analysis, with a focus on expression profiling in hub genes and immune cells. We validated that monocytes and nonclassical monocytes were upregulated in the ASD group using peripheral blood (30 children with ASD and 30 age and sex-matched typically developing children) using flow cytometry. The receiver operating characteristic curves (PSMC4 and ALAS2) and analysis stratified by ASD severity (LIlRB1 and CD69) showed that they had predictive value using the "training" and verification groups. Three immune cell types - monocytes, M2 macrophages, and activated dendritic cells - had different degrees of correlation with 15 identified hub genes. In addition, we analyzed the miRNA-mRNA network and agents-gene interactions using miRNA databases (starBase and miRDB) and the DSigDB database. Two miRNAs (miR-342-3p and miR-1321) and 23 agents were linked with ASD. These findings suggest that dysregulation of the immune system may contribute to ASD development, especially dysregulation of monocytes and monocyte-derived cells. ASD-related hub genes may serve as potential predictors for ASD, and the potential ASD-related miRNAs and agents identified here may open up new strategies for the prevention and treatment of ASD.

Non-Enzymatic Antioxidants against Alzheimer's Disease: Prevention, Diagnosis and Therapy

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by progressive memory loss and cognitive decline. Although substantial research has been conducted to elucidate the complex pathophysiology of AD, the therapeutic approach still has limited efficacy in clinical practice. Oxidative stress (OS) has been established as an early driver of several age-related diseases, including neurodegeneration. In AD, increased levels of reactive oxygen species mediate neuronal lipid, protein, and nucleic acid peroxidation, mitochondrial dysfunction, synaptic damage, and inflammation. Thus, the identification of novel antioxidant molecules capable of detecting, preventing, and counteracting AD onset and progression is of the utmost importance. However, although several studies have been published, comprehensive and up-to-date overviews of the principal anti-AD agents harboring antioxidant properties remain scarce. In this narrative review, we summarize the role of vitamins, minerals, flavonoids, non-flavonoids, mitochondria-targeting molecules, organosulfur compounds, and carotenoids as non-enzymatic antioxidants with AD diagnostic, preventative, and therapeutic potential, thereby offering insights into the relationship between OS and neurodegeneration.

Garden Cress (Lepidium sativum) Seeds Ameliorated Aluminum-Induced Alzheimer Disease in Rats Through Antioxidant, Anti-Inflammatory, and Antiapoptotic Effects

Background

Bioaccumulation of aluminum in the brain is associated with adverse neuroinflammatory and neurodegenerative changes, such as those seen in Alzheimer's disease (AD).

Objective

This study aimed to assess the impact of the administration of Lepidium sativum (LS) extract on behavioral, biochemical, and cerebral histopathological changes in rats with AlCl₃-induced AD and explore the mechanism behind this effect.

Materials and Methods

This study was conducted on 40 male albino rats divided into four groups (n=10): LS (control, 20 mg/kg body weight for 8 weeks), AD (AlCl_3, 10 mg/kg body weight), and an LS-treated AD group. Behavioral assessment included radial armed maze and active avoidance training tests. Proinflammatory cytokines, oxidant/antioxidant markers, Aβ, AchE, tau protein, TGFβ₁, homocysteine, folic acid, and vitamin B₁₂ were biochemically assessed in the serum. The cerebral cortex was histopathologically examined.

Results

AlCl₃ administration significantly impaired rats' memory, indicating AD-like behavioral changes, significantly increased (P<0.001) oxidative stress markers, enhanced proinflammatory cytokines, and significantly increased AChE (P<0.001) adding to cytotoxic effects and neuronal loss in the cerebral cortex. LS administration significantly improved the antioxidant parameters, reduced proinflammatory cytokines, and alleviated AD-associated histopathological changes.

Conclusion

LS ameliorated AlCl₃-induced changes through its antioxidant, anti-inflammatory, and antiapoptotic effects, suggesting that it has a neuroprotective effect.

A Review on Garlic as a Supplement for Alzheimer’s Disease: A Mechanistic Insight into its Direct and Indirect Effects

Alzheimer’s disease (AD) is one of the most complicated neurodegenerative diseases causing dementia in human beings. Aside from that, the incidence of AD is increasing and its treatment is very complicated. There are several known hypotheses regarding the pathology of Alzheimer’s disease, including the amyloid beta hypothesis, tau hypothesis, inflammation hypothesis, and cholinergic hypothesis, which are investigated in different researches to completely elucidate the pathology of AD. Besides, some new mechanisms, such as immune, endocrine, and vagus pathways, as well as bacteria metabolite secretions, are being explained as other causes to be somehow related to AD pathogenesis. There is still no definite treatment for Alzheimer’s disease that can completely cure and eradicate AD. Garlic (Allium sativum) is a traditional herb used as a spice in different cultures, and due to the organosulfur compounds, like allicin, it possesses highly anti-oxidant properties; the benefits of garlic in cardiovascular diseases, like hypertension and atherosclerosis, have been examined and reviewed, although its beneficiary effects in neurodegenerative diseases, such as AD, are not completely understood. In this review, we discuss the effects of garlic based on its components, such as allicin and S-allyl cysteine, on Alzheimer’s disease and the mechanisms of garlic components that can be beneficiary for AD patients, including its effects on amyloid beta, oxidative stress, tau protein, gene expression, and cholinesterase enzymes. Based on the literature review, garlic has been revealed to have beneficiary effects on Alzheimer’s disease, especially in animal studies; however, more studies should be done on humans to find the exact mechanisms of garlic’s effects on AD patients.

AlCl3 induced learning and memory deficit in zebrafish

Aluminium is a metal known to cause neurotoxicity in the brain, by promoting neurodegeneration and affecting memory and cognitive ability. AlCl₃ has been reported to enhance reactive oxygen species (ROS) and inflammatory markers which are further responsible for the degeneration of neurons. AlCl₃ exposure to zebrafish causes behavioral, biochemical, and neurochemical changes in the brain. In our study, Zebrafish were exposed to AlCl₃ at three different doses (50 µg/L, 100 µg/L, and 200 µg/L) for four consecutive days. On days 1st and 4th, a novel diving test was performed to check anxiety in zebrafish. T - maze and novel object recognition test were used to check the memory on days 3rd and 4th with the help of ANY-maze software. On the last day (4th day), zebrafishes were sacrificed and whole brains were used to perform the biochemical, neurotransmitters, histopathological, and immunohistochemistry analysis. Our study revealed that AlCl₃ exposure significantly decreased the total distance traveled, and the number of entries in the top zone and increased the time spent in the bottom zone, checked through the novel diving test. In the T maze test, AlCl₃ treated zebrafish showed significantly increased transfer latency to the favorable zone and time spent, and the number of entries to the unfavorable zone. The exploration time with the novel object was reduced significantly after AlCl₃ treatment. Moreover, reduced glutathione (GSH) and superoxide dismutase (SOD) levels were significantly reduced in AlCl₃ treated zebrafish whereas malondialdehyde (MDA) level was found to be increased, indicating high oxidative stress. The neurotransmitters level was also disturbed indicated by the significantly decreased GABA, dopamine, noradrenaline, and Serotonin levels and increased glutamate level in the brain of zebrafish treated with AlCl₃. Moreover, histopathological and immunohistochemistry study shows a markedly increased number of pyknotic neurons and reduced the expression of Nrf2 in the zebrafish brain after AlCl₃ exposure. These findings suggest that AlCl₃ significantly causes behavioral, biochemical, neurotransmitters, morphological, and molecular changes in zebrafish, ultimately causing AD.

Therapeutic Potential of Allicin and Aged Garlic Extract in Alzheimer’s Disease

Garlic, Allium sativum, has long been utilized for a number of medicinal purposes around the world, and its medical benefits have been well documented. The health benefits of garlic likely arise from a wide variety of components, possibly working synergistically. Garlic and garlic extracts, especially aged garlic extracts (AGEs), are rich in bioactive compounds, with potent anti-inflammatory, antioxidant and neuroprotective activities. In light of these effects, garlic and its components have been examined in experimental models of Alzheimer’s disease (AD), the most common form of dementia without therapy, and a growing health concern in aging societies. With the aim of offering an updated overview, this paper reviews the chemical composition, metabolism and bioavailability of garlic bioactive compounds. In addition, it provides an overview of signaling mechanisms triggered by garlic derivatives, with a focus on allicin and AGE, to improve learning and memory.

Allicin, an Antioxidant and Neuroprotective Agent, Ameliorates Cognitive Impairment

Allicin (diallylthiosulfinate) is a defense molecule produced by cellular contents of garlic (Allium sativum L.). On tissue damage, the non-proteinogenic amino acid alliin (S-allylcysteine sulfoxide) is converted to allicin in an enzyme-mediated process catalysed by alliinase. Allicin is hydrophobic in nature, can efficiently cross the cellular membranes and behaves as a reactive sulfur species (RSS) inside the cells. It is physiologically active molecule with the ability to oxidise the thiol groups of glutathione and between cysteine residues in proteins. Allicin has shown anticancer, antimicrobial, antioxidant properties and also serves as an efficient therapeutic agent against cardiovascular diseases. In this context, the present review describes allicin as an antioxidant, and neuroprotective molecule that can ameliorate the cognitive abilities in case of neurodegenerative and neuropsychological disorders. As an antioxidant, allicin fights the reactive oxygen species (ROS) by downregulation of NOX (NADPH oxidizing) enzymes, it can directly interact to reduce the cellular levels of different types of ROS produced by a variety of peroxidases. Most of the neuroprotective actions of allicin are mediated via redox-dependent pathways. Allicin inhibits neuroinflammation by suppressing the ROS production, inhibition of TLR4/MyD88/NF-κB, P38 and JNK pathways. As an inhibitor of cholinesterase and (AChE) and butyrylcholinesterase (BuChE) it can be applied to manage the Alzheimer's disease, helps to maintain the balance of neurotransmitters in case of autism spectrum disorder (ASD) and attention deficit hyperactive syndrome (ADHD). In case of acute traumatic spinal cord injury (SCI) allicin protects neuron damage by regulating inflammation, apoptosis and promoting the expression levels of Nrf2 (nuclear factor erythroid 2-related factor 2). Metal induced neurodegeneration can also be attenuated and cognitive abilities of patients suffering from neurological diseases can be ameliorates by allicin administration.

Spermine protects aluminium chloride and iron-induced neurotoxicity in rat model of Alzheimer's disease via attenuation of tau phosphorylation, Amyloid-β (1-42) and NF-κB pathway

Alzheimer's disease (AD) is the most prevalent type of dementia, characterized by a gradual decline in cognitive and memory functions of the aged peoples. Long-term exposure to heavy metals (aluminium and iron) cause neurotoxicity by amyloid plaques accumulation, tau phosphorylation, increased oxidative stress, neuroinflammation, and cholinergic neurons degeneration, contributes to the development of AD-like symptoms. The present research work is designed to investigate the neuroprotective effect of spermine in aluminium chloride (AlCl₃), and iron (Fe) induced AD-like symptoms in rats. Rats were administered of AlCl₃ (100 mg/kg p.o.) alone and in combination with iron (120 μg/g, p.o.) for 28 days. Spermine (5 and 10 mg/kg) through intraperitoneal (i.p.) route was given for 14 days. The recognition and spatial memory impairment were tasted using Morris water maze (MWM), actophotometer, and Novel Object Recognition test (NORT). All the rats were sacrificed on day 29, brains were isolated, and tissue homogenate was used for neuroinflammatory, biochemical, neurotransmitters, metals concentration, and nuclear factor-kappa B (NF-κB) analysis. In the present study, AlCl₃ and iron administration elevated oxidative stress, cytokines release, dysbalanced neurotransmitters concentration, and biochemical changes. Rats treated with spermine dose-dependently improved the recognition and spatial memory, attenuated proinflammatory cytokine release, and restored neurotransmitters concentration and antioxidant enzymes. Spermine also mitigated the increased beta-amyloid (Aβ42), with downregulation of tau phosphorylation. Furthermore, spermine augmented the hippocampal levels of B cell leukaemia/lymphoma-2 (Bcl-2), diminished nuclear factor-kappa B (NF-κB) and caspase-3 (casp-3) expression. Moreover, spermine exhibited the neuroprotective effect through anti-inflammatory, antioxidant, neurotransmitters restoration, anti-apoptotic Aβ42 concentration.