Astaxanthin ameliorates aluminum chloride-induced spatial memory impairment and neuronal oxidative stress in mice

Detection of toxicity induced by acrylonitrile exposure in rats and the protective role of astaxanthin using neurotransmitters in predicting 8-hydroxy-2'-deoxyguanosine and protein carbonyl levels

BACKGROUND

Neurotransmitters could be used as excellent predictors for oxidative stress products assessment. Acrylonitrile (ACN) is a common material used in the industry for the production of plastics, synthetic rubber, resins, fibers, adhesives, and chemical intermediates. However, it may affect the nervous system, neurotransmitter disruption, organs toxicity, protein and DNA damage through propagation of oxidative stress.

OBJECTIVE

This study aimed to provide equations for predicting the levels of oxidative stress products resulting from acrylonitrile exposure as a model of oxidation reaction stimulation in rats. In addition, astaxanthin (ASTX) protective potential against acrylonitrile toxicity is evaluated.

METHODS

Fifty rats were divided equally into five groups according to experimental design. Brain neurotransmitters, LDH, antioxidants, and oxidative stress markers were assessed. Furthermore, multiple regression analysis was used to design the desired equations.

RESULTS

Multiple regression analysis was employed to develop predictive equations for oxidative stress markers based on neurotransmitter levels and lactate dehydrogenase activity. The generated models demonstrated a significant relationship between oxidative damage indicators and key biochemical parameters. The predictive equations were as follows: 8OHdG = 333.77 - 159.21 × DOP + 0.07 × LDH, PC = 6.88-6.98 × NE + 0.002 × LDH, and MDA = 76.86 - 38.67 × DOP + 0.009 × LDH. These equations provide a novel approach for estimating oxidative stress levels. Additionally, there was an improvement in neurotransmitters levels by using ASTX. Also, there was an extreme increase in total antioxidant capacity (TAC) and a significant decrease in cells biological macromolecules damage.

CONCLUSION

The regression analysis showed that LDH, dopamine, and norepinephrine are good predictors for the concentration of oxidative products of biological macromolecules, including 8-hydroxy-2'-deoxyguanosine (8-OHdG) as a marker of DNA oxidation, protein carbonyl (PC) as a marker of protein oxidation, and malondialdehyde (MDA) as a marker of lipid peroxidation. Moreover, ASTX could efficiently ameliorate acrylonitrile toxicity.

The effect of azelaic acid on AlCl3-induced neurocognitive impairments and molecular changes in the hippocampus of rats

OBJECTIVES

Cognitive function plays a pivotal role in assessing an individual's quality of life. This research aimed to investigate how azelaic acid (AzA), a natural dicarboxylic acid with antioxidant and anti-inflammatory properties, affects aluminium chloride (AlCl3)-induced behavioural changes and biochemical alterations in the hippocampus of rats.

METHODS

Thirty-two male Wistar rats divided into four groups received distilled water, AzA 50 mg/kg, AlCl3 100 mg/kg and AzA plus AlCl3, respectively, by oral gavage for 6 weeks. Behavioural changes were evaluated using open-field maze, elevated plus maze, novel object recognition (NOR), passive avoidance task, and Morris water maze (MWM) tests. Also, malondialdehyde (MDA), carbonyl protein, tumour necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β), nuclear factor-kappa B (NF-κB), C/EBP homologous protein (CHOP), glycogen synthase kinase-3 beta (GSK-3β), brain-derived neurotrophic factor (BDNF) and acetylcholinesterase (AChE) activity were examined.

RESULTS

AzA significantly affected AlCl3-provoked anxiety-like behaviours and learning and memory impairments. It also reduced the toxic effect of AlCl3 on MDA, carbonyl protein, TNF-α, IL-1β, NF-κB and GSK-3β status; however, its beneficial effects on AlCl3-induced changes of CHOP, BDNF and AChE activity were not significant.

CONCLUSION

These findings disclosed that AzA could improve behavioural and cognitive function and almost limit the oxidative stress and neuroinflammation caused by AlCl3.

Potential protection of resveratrol-tempeh against nephrotoxic and hepatotoxic histological damage in mice induced by aluminum

Aluminum is a widely distributed metal that, while generally safe at low levels, can become toxic when accumulated in the body. Its exposure is daily through various sources, including food, water, and medications. High levels of aluminum have been shown to adversely affect the kidneys and liver, leading to significant organ damage. Resveratrol-tempeh is a safe protective agent against organ damage caused by aluminum. Here, we investigated the impact of resveratrol on liver and kidney toxicity and Al-induced levels of catalase and malondialdehyde. The mice group was the control group, Al-group, Al+REST5-group, and Al+REST10-group. Aluminum and resveratrol were administered intraperitoneally to mice for four weeks, but resveratrol was administered one hour after exposure to aluminum. Mice were killed by cervical dislocation; the liver and kidney were isolated for slide, and the level of an antioxidant enzyme of catalase and oxidant of malondialdehyde was measured. The results showed that administration of aluminum at a dose of 200 mg/kg body weight caused glomerular shrinkage and proximal tubule degeneration in the kidneys. In addition, it also caused liver tissue damage, with hepatocytes undergoing degeneration, sinusoids dilating, and decreased body weight in the mice. Administration of resveratrol-tempeh tended to decrease malondialdehyde levels and increase catalase activity, although the changes were not significant. It seems that resveratrol-tempeh can repair liver and kidney damage and restore them to normal conditions. Conclusion: Aluminum at 200 mg/kg is toxic to mice. Resveratrol-tempeh can be considered a potential candidate to protect kidney and liver damage caused by aluminum chloride toxicity.

Rosiridin Protects Against Aluminum Chloride-Induced Memory Impairment via Modulation of BDNF/NFκB/PI3K/Akt Pathway in Rats

Background and Objectives: Rosiridin is a monoterpene with outstanding monoamine inhibitory activity that is useful to treat depressive episodes and rapid-onset dementia. The current investigation aims to evaluate the neurologically protective impact of rosiridin, which opposes aluminum chloride (AlCl3) and causes memory dysfunction in rats. Materials and Methods: Memory impairment was developed in Wistar rats by administering AlCl3 (100 mg/kg p.o.) orally for 42 days and then supplemented with rosiridin at 10 and 20 mg/kg/p.o. Upon completion of the investigation, the behavior factor was performed utilizing the Y-maze, Morris Water Maze, and open field tests. Estimating numerous biological factors, such as nitric oxide (NO), oxidative stress (malondialdehyde MDA), acetylcholinesterase (AChE), butyrylcholinesterase levels (BuChE), antioxidants (glutathione GSH, catalase CAT, and superoxide dismutases SODs) and neurotransmitter (serotonin-5HT, dopamine-DA, acetylcholine-Ach) in the brain. Furthermore, interleukin-6 (IL-6), IL-1β, tumor necrosis factor (TNF-α), brain-derived neurotrophic factor (BNDF), nuclear factor kappa B (NFᴋB), phosphatidylinositol 3-kinase (PI3K), and pAkt were assessed in the diffused brain cells. Results: The rosiridin-treated group significantly improved in terms of behavioral parameters, including in the Y-maze, Morris Water Maze, and open field tests. Further, rosiridin restored biochemical parameters, including NO, oxidative stress AChE, BuChE, antioxidants, neurotransmitters, IL-6, IL-1β, TNF-α, BNDF, NFᴋB, PI3K, and pAkt compared to AlCl3. Conclusions: The current investigation reveals that rosiridin could ameliorate the impairment of memory that AlCl3 causes in rats via improvements in behavioral and restored biochemical parameters.

A marine-derived antioxidant astaxanthin as a potential neuroprotective and neurotherapeutic agent: A review of its efficacy on neurodegenerative conditions

Astaxanthin is a potent lipid-soluble carotenoid produced by several different freshwater and marine microorganisms, including microalgae, bacteria, fungi, and yeast. The proven therapeutic effects of astaxanthin against different diseases have made this carotenoid popular in the nutraceutical market and among consumers. Recently, astaxanthin is also receiving attention for its effects in the co-adjuvant treatment or prevention of neurological pathologies. In this systematic review, studies evaluating the efficacy of astaxanthin against different neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease, multiple sclerosis, cerebrovascular diseases, and spinal cord injury are analyzed. Based on the current literature, astaxanthin shows potential biological activity in both in vitro and in vivo models. In addition, its preventive and therapeutic activities against the above-mentioned diseases have been emphasized in studies with different experimental designs. In contrast, none of the 59 studies reviewed reported any safety concerns or adverse health effects as a result of astaxanthin supplementation. The preventive or therapeutic role of astaxanthin may vary depending on the dosage and route of administration. Although there is a consensus in the literature regarding its effectiveness against the specified diseases, it is important to determine the safe intake levels of synthetic and natural forms and to determine the most effective forms for oral intake.

Astaxanthin reduces TBPH-induced neurobehavioral deficits in mice by the ROS-ERK1/2-FOS pathway

The persistence of the novel brominated flame retardant, bis(2-ethylhexyl)-3,4,5,6-tetrabromophthalate (TBPH), in the environment and its potential for bioaccumulation in living organisms, including humans, further exacerbate its health risks. Therefore, ongoing research is crucial for fully understanding the extent of TBPH's neurotoxicity and for developing effective mitigation strategies. This study aims to investigate the potential neurotoxicity of TBPH on mouse neurobehavior and to evaluate the protective effects of the natural antioxidant astaxanthin (AST) against TBPH-induced neurotoxicity. The results indicate that exposure to TBPH can lead to a decline in learning and memory abilities and abnormal behaviors in mice, which may be associated with oxidative stress responses and apoptosis in the hippocampus. TBPH may disrupt the normal function of hippocampal neurons by activating the extracellular signal-regulated kinase 1/2 (ERK1/2) signaling pathway. Mice exposed to TBPH treated with AST showed improved learning and memory abilities in the Morris water maze (MWM) and Step-down test (SDT). AST, through its antioxidant action, was able to significantly reduce the increase in reactive oxygen species (ROS) levels induced by TBPH, the increased expression of apoptosis markers, and the activation of the ERK1/2-FOS signaling pathway, alleviating TBPH-induced apoptosis in hippocampal neurons and improving neurobehavioral outcomes. These findings suggest that AST may alleviate the neurotoxicity of TBPH by modulating molecular events related to apoptosis and the ERK1/2-FOS signaling pathway. Thus, this study provides evidence for AST as a potential interventional strategy for the prevention or treatment of cognitive decline associated with environmental neurotoxicant exposure.

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.

Mefenamic Acid Loaded and TPGS Stabilized Mucoadhesive Nanoemulsion for the Treatment of Alzheimer's Disease: Development, Optimization, and Brain-Targeted Delivery via Olfactory Pathway

Alzheimer's disease (AD) is a very common disorder that affects the elderly. There are relatively few medications that can be used orally or as a suspension to treat AD. A mucoadhesive (o/w) nano emulsion of mefenamic acid was made by adding Carbopol 940P to the optimised drug nanoemulsion using distilled water as the aqueous phase (6%); Solutol HS: tween 20 (3.6%) as the surfactant and co-surfactant; and clove oil: TPGS (0.4%) as the oil phase and mefenamic acid as the drug (2.8 mg/ml). The mucoadhesive nanoemulsion (S40.5%w/v) had a particle size of 91.20 nm, polydispersity index of 0.270, and surface charge of - 12.4 mV. Significantly higher (p < 0.001) drug release (89.37%) was observed for mucoadhesive drug formulation in comparison to mucoadhesive drug suspension (25.64%) at 8 h. The ex vivo nasal permeation of 83.03% in simulated nasal fluid and 85.71% in artificial cerebrospinal fluid was observed. The percent inhibition and inhibitory concentration (IC50) of mucoadhesive drug nanoemulsion were found to be 91.57 ± 2.69 and 6.76 respectively. Higher cell viability on glioblastoma cells (85-80%) was researched for mucoadhesive nanoemulsion as compared to drug suspension (80-70%). Significantly higher (p < 0.001) drug absorption and Cmax (491.94 ± 24.13 ng/ml) of mucoadhesive drug nanoemulsion were observed than mucoadhesive drug suspension (107.46 ± 11.46 ng/ml) at 8 h. The stability studies confirmed that the formulation was stable at 40°C ± 2°C and 75 ± 5% RH. The authors concluded that the mucoadhesive mefenamic acid-loaded nanoemulsion may be an effective technique for treating Alzheimer's disease by intranasal route.

Combination of epigallocatechin 3 gallate and curcumin improves D-galactose and normal-aging associated memory impairment in mice

Previously, we observed curcumin improves aging-associated memory impairment in D-galactose (D-gal) and normal-aged (NA) mice. Evidence showed that multiple agents can be used in managing aging-induced memory dysfunction, drawn by the contribution of several pathways. Curcumin and Epigallocatechin 3 gallate (EGCG) combination substantially reduced the oxidative stress that commonly mediates aging. This study examined the combined effect of EGCG and curcumin on memory improvement in two recognized models, D-gal and normal-aged (NA) mice. The co-administration of EGCG and curcumin significantly (p < 0.05) increased retention time detected by passive avoidance (PA) and freezing response determined in contextual fear conditioning (CFC) compared to the discrete administration of EGCG or curcumin. Biochemical studies revealed that the combination of EGCG and curcumin remarkably ameliorated the levels (p < 0.05) of glutathione, superoxide dismutase, catalase, advanced oxidation protein products, nitric oxide, and lipid peroxidation compared to the monotherapy of EGCG or curcumin in mice hippocampi. The behavioral and biochemical studies revealed that the combination of EGCG and curcumin showed better improvement in rescuing aging-associated memory disorders in mice. EGCG and curcumin combination could serve as a better choice in managing aging-related memory disorders.

Astaxanthin impact on brain: health potential and market perspective

Nowadays, there is an emergent interest in new trend-driven biomolecules to improve health and wellbeing, which has become an interesting and promising field, considering their high value and biological potential. Astaxanthin is one of these promising biomolecules, with impressive high market growth, especially in the pharmaceutical and food industries. This biomolecule, obtained from natural sources (i.e., microalgae), has been reported in the literature to have several beneficial health effects due to its biological properties. These benefits seem to be mainly associated with Astaxanthin's high antioxidant and anti-inflammatory properties, which may act on several brain issues, thus attenuating symptoms. In this sense, several studies have demonstrated the impact of astaxanthin on a wide range of diseases, namely on brain disorders (such as Alzheimer's disease, Parkinson, depression, brain stroke and autism). Therefore, this review highlights its application in mental health and illness. Furthermore, a S.W.O.T. analysis was performed to display an approach from the market/commercial perspective. However, to bring the molecule to the market, there is still a need for more studies to increase deep knowledge regarding the real impact and mechanisms in the human brain.HIGHLIGHTSAstaxanthin has been mainly extracted from the algae Haematococcus pluvialisAstaxanthin, bioactive molecule with high antioxidant and anti-inflammatory propertiesAstaxanthin has an important protective effect on brain disordersAstaxanthin is highly marketable, mainly for food and pharmaceutical industries.

Centella asiatica Alleviates AlCl3-induced Cognitive Impairment, Oxidative Stress, and Neurodegeneration by Modulating Cholinergic Activity and Oxidative Burden in Rat Brain

Aluminum (Al) is linked to the development of many neurological disorders such as Alzheimer's disease (AD), Parkinson's disease, and autism. Centella asiatica (CA) is a regenerating herb traditionally used to stimulate memory. This study was designed to assess the neuroprotective role of ethanolic extract of CA (CAE) in AlCl₃-induced neurological conditions in rats. Adult rats were chronically treated with AlCl₃ (100 mg/kg b.w./day) for 60 days to establish the dementia model, and co-administration of CAE was evaluated for its ability to attenuate the toxic effect of AlCl₃. CAE was given orally at a dose of 150 and 300 mg/kg b.w./day, for 60 days. The behavioral performances of rats were tested through Y-maze and open field tests. Lipid peroxidation, superoxide dismutase, and catalase activity were evaluated to measure oxidative stress; and acetylcholinesterase (AChE) activity was assessed to evaluate cholinergic dysfunction in the rat brain. H&E staining was used to assess structural abnormalities in the cortex and hippocampus. The result showed that AlCl₃ induces cognitive dysfunction (impaired learning and memory, anxiety, diminished locomotor activity), oxidative stress, cholinergic impairment, and histopathological alteration in the rat brain. Co-administration of CAE with AlCl₃ markedly protects the brain from AlCl₃-induced cognitive dysfunction, oxidative stress, AChE activity, and cytoarchitectural alterations. Furthermore, 15 days CAE treatment after 45 days AlCl₃ administration markedly ameliorates the AlCl₃-induced neurotoxicity indicating its potential for therapeutic use.

Biochemical indexes and gut microbiota testing as diagnostic methods for Penaeus monodon health and physiological changes during AHPND infection with food safety concerns

Severe shrimp disease outbreaks have a destructive impact on shrimp aquaculture and its associated downstream food processing industries. Thus, it is essential to develop proper methods for shrimp disease control, which emphasizes the importance of food safety. In this study, we performed biochemical tests and gut microbiome analysis using uninfected control and Vp AHPND-infected Penaeus monodon samples. Biochemical tests were performed to assess the phenoloxidase (PO) activity, respiratory Burst (RB) activity, nitrite concentration, superoxide dismutase (SOD) activity, total hemocyte count (THC), and total protein concentrations. Overall, upregulations were detected in these biochemical tests, which showed the activation of the immune response in P. monodon during acute hepatopancreatic necrosis disease (AHPND) infection, especially at 6 hpi and 12 hpi. Besides that, shrimp gut samples were collected and pooled (n = 3), followed by DNA extraction, PCR amplification targeting the V3/V4 16S ribosomal RNA (rRNA) region, next-generation sequencing (NGS), and bioinformatics analysis. Proteobacteria was the most abundant phylum in both samples. The Rhodobacteraceae family and Maritimibacter genus were proposed to be vital forshrimp health maintenance. Vp AHPND bacterial colonization and secondary Vibrio infections were postulated to have occurred based on the higher abundances of Vibrionaceae family and Vibrio genus in the Vp AHPND-infected sample. Firmicutes phylum together with Photobacterium and Aliiroseovarius genera were inferred to be pathogenic or related factors of AHPND infections. In conclusion, physiology (immune response activation) and gut microbiome changes of disease tolerant P. monodon during AHPND infection were identified. Both biochemical tests and 16S rRNA analysis are proposed as a combined strategy for shrimp health diagnosis for ensuring shrimp health maintenance, disease control, and food safety.

Curcumin improves D-galactose and normal-aging associated memory impairment in mice: In vivo and in silico-based studies

Aging-induced memory impairment is closely associated with oxidative stress. D-Galactose (D-gal) evokes severe oxidative stress and mimics normal aging in animals. Curcumin, a natural flavonoid, has potent antioxidant and anti-aging properties. There are several proteins like glutathione S-transferase A1 (GSTA1), glutathione S-transferase omega-1 (GSTO1), kelch-like ECH-associated protein 1 (KEAP1), beta-secretase 1 (BACE1), and amine oxidase [flavin-containing] A (MAOA) are commonly involved in oxidative stress and aging. This study aimed to investigate the interaction of curcumin to these proteins and their subsequent effect on aging-associated memory impairment in two robust animal models: D-Gal and normal aged (NA) mice. The aging mice model was developed by administering D-gal intraperitoneally (i.p). Mice (n = 64) were divided into the eight groups (8 mice in each group): Vehicle, Curcumin-Control, D-gal (100mg/kg; i.p), Curcumin + D-gal, Astaxanthin (Ast) + D-gal, Normal Aged (NA), Curcumin (30mg/kg Orally) + NA, Ast (20mg/kg Orally) + NA. Retention and freezing memories were assessed by passive avoidance (PA) and contextual fear conditioning (CFC). Molecular docking was performed to predict curcumin binding with potential molecular targets. Curcumin significantly increased retention time (p < 0.05) and freezing response (p < 0.05) in PA and CFC, respectively. Curcumin profoundly ameliorated the levels of glutathione, superoxide dismutase, catalase, advanced oxidation protein products, nitric oxide, and lipid peroxidation in mice hippocampi. In silico studies revealed favorable binding energies of curcumin with GSTA1, GSTO1, KEAP1, BACE1, and MAOA. Curcumin improves retention and freezing memory in D-gal and nature-induced aging mice. Curcumin ameliorates the levels of oxidative stress biomarkers in mice. Anti-aging effects of curcumin could be attributed to, at least partially, the upregulation of antioxidant enzymes through binding with GSTA1, GSTO1, KEAP1, and inhibition of oxidative damage through binding with BACE1 and MAOA.

Protective effects of hydroxy-α-sanshool from the pericarp of Zanthoxylum bungeanum Maxim. On D-galactose/AlCl3-induced Alzheimer's disease-like mice via Nrf2/HO-1 signaling pathways

Hydroxy-α-sanshool (HAS) is an unsaturated fatty acid amide from Zanthoxylum bungeanum Maxim. with hypolipidemic, hypoglycemic, anti-inflammatory, and neurotrophic effects, etc. In this study, results indicated that HAS effectively ameliorated spontaneous locomotion deficit of mice induced by D-galactose (D-gal) and AlCl₃ treatment in open field test. Results of Morris water maze test (MWM) showed that HAS significantly improved the spatial learning and memory ability of aging mice. Histopathological evaluations revealed that HAS markedly alleviated morphological changes and increased number of Nissl neurons in hippocampus of D-gal/AlCl₃-induced Alzheimer's disease (AD)-like mice. HAS markedly reduced malondialdehyde (MDA) production, and increased the activity of antioxidative enzymes including superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT), showing an inhibitory effect on oxidative stress. Furthermore, HAS treatment obviously reversed the inhibitory expressions of mRNA and protein of HO-1 and Nrf2 in the hippocampus of AD mice, suggesting that neuroprotective effects of HAS against oxidative stress might be mediated by the Nrf2/HO-1 pathway. Meanwhile, HAS significantly inhibited neuronal apoptosis by decreasing mRNA and protein expressions of Cyt-c, Bax and Caspase 3, and increasing Bcl-2 expression in the hippocampus of AD mice. These results suggest that HAS have the potential to be developed as antioxidant drug for the prevention and early therapy of AD.

Dietary astaxanthin: an excellent carotenoid with multiple health benefits

Astaxanthin is a carotenoid widely found in marine organisms and microorganisms. With extensive use in nutraceuticals, cosmetics, and animal feed, astaxanthin will have the largest share in the global market for carotenoids in the near future. Owing to its unique molecular features, astaxanthin has excellent antioxidant activity and holds promise for use in biochemical studies. This review focuses on the observed health benefits of dietary astaxanthin, as well as its underlying bioactivity mechanisms. Recent studies have increased our understanding of the role of isomerization and esterification in the structure-function relationship of dietary astaxanthin. Gut microbiota may involve the fate of astaxanthin during digestion and absorption; thus, further knowledge is needed to establish accurate recommendations for dietary intake of both healthy and special populations. Associated with the regulation of redox balance and multiple biological mechanisms, astaxanthin is proposed to affect oxidative stress, inflammation, cell death, and lipid metabolism in humans, thus exerting benefits for skin condition, eye health, cardiovascular system, neurological function, exercise performance, and immune response. Additionally, preclinical trials predict its potential effects such as intestinal flora regulation and anti-diabetic activity. Therefore, astaxanthin is worthy of further investigation for boosting human health, and wide applications in the food industry.

Pomegranate juice reverses AlCl3-Induced neurotoxicity and improves learning and memory in female mice

BACKGROUND

Aluminum is a neurotoxic element that can accumulate in the brain and cause neurodegenerative disorders. In addition, the antioxidants found in pomegranate juice (PJ) are much more than those existing in other fruits. It was proven to provide protection against neurodegenerative diseases.

OBJECTIVES

This experiment aimed to clarify the amelioration efficiency of PJ against aluminum chloride-induced neurobehavioral and biochemical disorders in female mice.

METHODS

The female mice were given oral administrations for 35 days as follows. The control group received tap water, the PJ groups received 20% and 40% pomegranate juice, the aluminum chloride (AlCl₃) group was treated with 400 mg/kg AlCl₃, and the last two groups received AlCl₃ + 20% PJ and AlCl₃ + 40% PJ, respectively. The neurobehavioral features were assessed by shuttle box, T-maze, and Morris water maze devices. Furthermore, the neurotransmitters and oxidative indicators in the brains of the female mice were determined at the end of experiment.

RESULTS

Significant effects of AlCl₃ were observed on female mice in the body weight, during the behavioral tasks (shuttle box, T-maze, and Morris water maze), and in neurotransmitters and oxidative stress parameters. Pomegranate juice, especially at low concentrations, induced remarkable improvements in body weight, spatial memory and learning during T-maze, Morris water maze and shuttle box tasks, as well as in neurotransmitters and oxidative biomarkers in the AlCl₃-treated female mice.

CONCLUSION

PJ reversed AlCl₃-induced neurotoxicity and improved learning and memory in female mice. However, PJ contains a group of antioxidants that may be considered double-edged swords in the cellular redox status especially at high doses.

Natural antioxidants in diabetes treatment and management: prospects of astaxanthin

Diabetes remains a major health emergency in our entire world, affecting hundreds of millions of people worldwide. In conjunction with its much-dreaded complications (e.g., nephropathy, neuropathy, retinopathy, cardiovascular diseases, etc.) it substantially reduces the quality of life, increases mortality as well as economic burden among patients. Over the years, oxidative stress and inflammation have been highlighted as key players in the development and progression of diabetes and its associated complications. Much research has been devoted, as such, to the role of antioxidants in diabetes. Astaxanthin is a powerful antioxidant found mostly in marine organisms. Over the past years, several studies have demonstrated that astaxanthin could be useful in the treatment and management of diabetes. It has been shown to protect β-cells, neurons as well as several organs including the eyes, kidney, liver, etc. against oxidative injuries experienced during diabetes. Furthermore, it improves glucose and lipid metabolism along with cardiovascular health. Its beneficial effects are exerted through multiple actions on cellular functions. Considering these and the fact that foods and natural products with biological and pharmacological activities are of much interest in the 21st-century food and drug industry, astaxanthin has a bright prospect in the management of diabetes and its complications.

Neuropharmacological studies of ethanolic extract of Vaccinium corymbosum on Alzheimer’s type dementia and catatonia in Swiss albino mice

Introduction: Neuroactive herbal drugs enriched with antioxidants are valuable in treating neurocognitive dysfunction and Vaccinium corymbosum, enriched with antioxidant phytochemicals, is used for treating memory disorders. Hence, the present study evaluated the neuroprotective effects of ethanolic extract of Vaccinium corymbosum (EEVC) on aluminium chloride(AlCl3)-induced Alzheimer’s type of dementia and haloperidol-induced catalepsy-associated behavioural changes. Methods:In vitro antioxidant potential was evaluated using 1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS). The total phenolic content (TPC) was quantified. For in vivo studies, AlCl3 (100 mg/kg) was orally administered for 42 days, whereas the EEVC was administered on the 21st day until the 42nd day in two doses (200 mg/kg and 400 mg/kg). In the haloperidol-induced group, EEVC was treated for 21 days, and haloperidol (1 mg/kg) was administered to induce behavioural changes. Open-field, Y-Maze and traction tests were performed, and the mice brain acetylcholinesterase (AChE) enzyme was determined. Results: IC50 values in DPPH and ABTS assays were 85.5 μg/mL and 80 μg/mL, respectively and the total phenolic content of EEVC was found to be 0.166 mg. In a behavioral study, animals treated with 200 mg/kg and 400 mg/kg of EEVC exhibited a neuroprotective impact on AlCl3-induced neurodegeneration and haloperidol-induced behavioral changes with significant inhibition (P < 0.05 and P < 0.01, respectively) in acetylcholinesterase enzyme. Conclusion: The neuroprotection by EEVC postulated that it is a promising therapeutic agent for treating behavioral and cognitive dysfunctions. Further investigations on pro-inflammatory cytokine and neuroendocrine regulation in transgenic Alzheimer’s disease (AD)models complement the therapeutic value of V. corymbosum.

Pomegranate juice rescues developmental, neurobehavioral and biochemical disorders in aluminum chloride-treated male mice

PURPOSE

Aluminum (Al) is a harmful metal to organisms and is capable of entering the human body in multiple ways, such as through drinking, breathing, deodorant use, and vaccination. This study examined the prospective toxicity of Al and the protective attributes of pomegranate juice (PJ) on neurobehavioral and biochemical parameters of male mice.

METHODS

Six groups of male mice were treated for 35 days with 20 % PJ (group II), 40 % PJ (group III), 400 mg/kg Al (group IV), Al + 20 % PJ (group V), Al + 40 % PJ (group VI) or tap water (control, group I). Behavioral assessments were conducted for learning and memory evaluations at the end of experiment. In addition, the forebrain was isolated for biochemical analysis.

RESULTS

The exposure of male mice to Al decreased learning and memory retention in the shuttle box, Morris water-maze and T-Maze tests. Biochemical analysis revealed significant depletions in neurotransmitters including DA, 5-HT and AChE and oxidative proteins including GSH, GST, CAT and SOD and increased TBARES levels in Al-treated mice compared to untreated mice. Pomegranate juice provided protection against these effects after Al exposure by ameliorating learning and memory retention and oxidative state in a dose-independent manner.

CONCLUSION

Our data demonstrated that Al exposure caused behavioral and biochemical disorders. Pomegranate juice in lower dose has beneficial properties for health and can be used as a source of antioxidants to reduce the toxicity of Al and other substances.

Astaxanthin protects cognitive function of vascular dementia

OBJECTIVE

The purpose of this study was to evaluate the effect of astaxanthin (AST) on cognition function, inflammatory response and oxidative stress in vascular dementia (VD) mice.

METHOD

VD mice model was established by left unilateral common carotid arteries occlusion (LUCCAO). Following LUCCAO, AST was intragastrically administered for 30 days. Object recognition test and morris water maze test were used to evaluate cognitive function. Hematoxylin and eosin staining was performed to observe the hippocampal neuron structure. Enzyme-linked immunosorbent assay kit and bicinchoninic acid kit were respectively adopted to measure IL-1β and IL-4 protein expression and superoxide dismutase (SOD) activity and malondialdehyde (MDA) content in hippocampus and prefrontal cortex.

RESULTS

AST improved the discrimination ability of VD mice. The escape latency and path length of VD mice treated with AST were dramatically reduced. Besides, AST 200 mg/kg enhanced crossing platform time and the number of times crossing the platform quadrant, and alleviated the morphological impairment in VD mice. Moreover, we found that AST inhibited IL-1β expression and MDA content, whereas promoted IL-4 expression and SOD activity in a dose-dependent manner.

CONCLUSION

AST could improve cognitive impairment and hippocampal neurons in VD mice, which may be related to suppression of inflammatory response and oxidative stress.

Aluminum maltolate triggers ferroptosis in neurons: mechanism of action

Aluminum (Al), a neurotoxic element, can induce Alzheimer's disease (AD) via triggering neuronal death. Ferroptosis is a new type of programmed cell death related to neurological diseases. Unfortunately, its role in aluminum-induced neuronal death remains completely unclear. This study aimed to investigate whether ferroptosis is involved in neuronal death in response to aluminum exposure as well as its underlying mechanism. In this study, rat adrenal pheochromocytoma (PC12) cells were treated with 200 μM aluminum maltolate (Al(mal)₃) for 24 h, and related biochemical indicators were assessed to determine whether ferroptosis was induced by aluminum in neurons. Then, the potential mechanism was explored by detecting of these genes and proteins associated with ferroptosis after adding ferroptosis-specific agonist Erastin (5 μM) and antagonist Ferrostatin-1 (Fer-1) (5 μM). The experimental results demonstrated that aluminum exposure significantly increased the death of PC12 cells and caused specific mitochondrial pathological changes of ferroptosis in PC12 cells. Further research confirmed that ferroptosis was triggered by aluminum in PC12 cells by means of activating the oxidative damage signaling pathway, which was displayed as inhibition of the cysteine/glutamate antiporter system (system Xc^-), causing the depletion of cellular glutathione (GSH) and inactivation of glutathione peroxidase (GSH-PX) eventually lead to accumulation of reactive oxygen species (ROS). Taken together, ferroptosis was a means of neuronal death induced by aluminum and oxidative damage may be its underlying mechanism, which also provided some new clues to potential target for the intervention and therapy of AD.

Bergamot essential oil attenuate aluminum-induced anxiety-like behavior through antioxidation, anti-inflammatory and GABA regulation in rats

A large number of studies showed that aluminum (Al) has potential neurotoxicity to human and animal bodies. Al-treated animals showed anxiety-like behavior, oxidative stress, neuroinflammation and γ-aminobutyric acid (GABA) changes. Bergamot essential oil (BEO) is a kind of well-known plant extract from the fresh fruit of bergamot. Previous studies suggested that BEO improved mood and relieved symptoms of stress-induced anxiety. This study was designed to study the effects of BEO on anxiety-like behavior, oxidative stress, neuroinflammation and GABA system in aluminum trichloride (AlCl₃) treated rats. Results showed that AlCl₃ exposure induced anxiety-like behavior in the elevated plus maze and the open field test. Moreover, AlCl₃ exposure decreased the level of GABA and the activity of glutathione peroxidase (GPx), catalase (CAT) and superoxide dismutase (SOD) in the hippocampus (HP) and the frontal cortex (FC). In addition, AlCl₃ exposure increased the levels of malondialdehyde (MDA) and 8-hydroxy-2'-deoxyguanosine (8-OHdG) and the levels of interleukin-1 beta (IL-1β), interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α) in the HP and the FC. To the contrary, co-administration of BEO and AlCl₃ improved the anxiety-like behavior, GABA system, oxidative stress and neuroinflammation. These results indicated that BEO can alleviate the anxiety-like behavior of AlCl₃-exposed rats through the combined action of antioxidant, anti-inflammatory and GABA regulation.

Astaxanthin Attenuates Fish Oil-Related Hepatotoxicity and Oxidative Insult in Juvenile Pacific White Shrimp (Litopenaeus vannamei)

The present study investigated the effect of dietary astaxanthin (AX) on the growth performance, antioxidant parameters, and repair of hepatopancreas damage in Pacific white shrimp (Litopenaeus vannamei). To evaluate the hepatopancreas protective function of AX in shrimps, we compared the effect of five isonitrogenous and isoenergetic diets under oxidized fish oil conditions with varying AX levels during the 50-day experimental period. The formulated diets were as follows: (i) OFO (oxidized fish oil); (ii) OFO/AX150 (oxidized fish oil + AX150 mg/kg); (iii) OFO/AX250 (oxidized fish oil + AX250 mg/kg); (iv) OFO/AX450 (oxidized fish oil + AX450 mg/kg); and, (v) control group (fresh fish oil). Results showed that the oxidized fish oil with 275.2 meq/kg peroxide value (POV) resulted in a substantial decrease in the final body weight of L. vannamei (P > 0.05) and induced some visible histopathological alterations in the hepatopancreas. Growth performance was significantly higher in shrimps fed with the OFO/AX450 diet than those fed with the OFO diet (p < 0.05). However, no significant difference was observed when the OFO/AX450 diet was compared to the control diet containing fresh fish oil (p > 0.05). Moreover, shrimps under the OFO/AX450 diet displayed a significant improvement in hepatopancreatic health and showed a reduction of malondialdehyde (MDA) compared to those under the OFO diet (p < 0.05). Dietary AX improved the antioxidant capacity of L. vannamei by increasing the catalase (CAT) activity in the hemolymph. Acute salinity change test showed a higher shrimp survival rate under OFO/AX450 diet than the OFO diet (p < 0.05), suggesting that AX can contribute to enhanced stress tolerance. In conclusion, our data suggest that AX confers dose-dependent protection against OFO-induced oxidative insults and hepatopancreatic damage in shrimp.

Natural Compounds Rosmarinic Acid and Carvacrol Counteract Aluminium-Induced Oxidative Stress

Aluminum accumulation, glutathione (GSH) and malondialdehyde (MDA) concentrations as well as catalase (CAT) and superoxide dismutase (SOD) activities were determined in erythrocytes and brain and liver homogenates of BALB/c mice treated with Al3+ (7.5 mg/kg/day (0.15 LD50) as AlCl3 (37.08 mg/kg/day), whereas HCl (30.41 mg/kg/day) was used as Cl- control, the treatments were performed for 21 days, i.p., in the presence and absence of rosmarinic acid (0.2805 mg/kg/day (0.05 LD50), 21 days, i.g.) or carvacrol (0.0405 mg/kg/day (0.05 LD50), 21 days, i.g.). The treatment with AlCl3 increased GSH concentration in erythrocytes only slightly and had no effect on brain and liver homogenates. Rosmarinic acid and carvacrol strongly increased GSH concentration in erythrocytes but decreased it in brain and liver homogenates. However, AlCl3 treatment led to Al accumulation in mice blood, brain, and liver and induced oxidative stress, assessed based on MDA concentration in the brain and liver. Both rosmarinic acid and carvacrol were able to counteract the negative Al effect by decreasing its accumulation and protecting tissues from lipid peroxidation. AlCl3 treatment increased CAT activity in mice brain and liver homogenates, whereas the administration of either rosmarinic acid or carvacrol alone or in combination with AlCl3 had no significant effect on CAT activity. SOD activity remained unchanged after all the treatments in our study. We propose that natural herbal phenolic compounds rosmarinic acid and carvacrol could be used to protect brain and liver against aluminum induced oxidative stress leading to lipid peroxidation.

Anti-inflammatory Property of AMP-activated Protein Kinase

BACKGROUND

One of the many debated topics in inflammation research is whether this scenario is really an accelerated form of human wound healing and immunityboosting or a push towards autoimmune diseases. The answer requires a better understanding of the normal inflammatory process, including the molecular pathology underlying the possible outcomes. Exciting recent investigations regarding severe human inflammatory disorders and autoimmune conditions have implicated molecular changes that are also linked to normal immunity, such as triggering factors, switching on and off, the influence of other diseases and faulty stem cell homeostasis, in disease progression and development.

METHODS

We gathered around and collected recent online researches on immunity, inflammation, inflammatory disorders and AMPK. We basically searched PubMed, Scopus and Google Scholar to assemble the studies which were published since 2010.

RESULTS

Our findings suggested that inflammation and related disorders are on the verge and interfere in the treatment of other diseases. AMPK serves as a key component that prevents various kinds of inflammatory signaling. In addition, our table and hypothetical figures may open a new door in inflammation research, which could be a greater therapeutic target for controlling diabetes, obesity, insulin resistance and preventing autoimmune diseases.

CONCLUSION

The relationship between immunity and inflammation becomes easily apparent. Yet, the essence of inflammation turns out to be so startling that the theory may not be instantly established and many possible arguments are raised for its clearance. However, this study might be able to reveal some possible approaches where AMPK can reduce or prevent inflammatory disorders.

The Role of the Reactive Oxygen Species Scavenger Agent, Astaxanthin, in the Protection of Cisplatin-Treated Patients Against Hearing Loss

Emerging evidence of significant hearing loss occurring shortly after cisplatin administration in cancer patients has stimulated research into the causes and treatment of this side effect. Although the aetiology of cisplatin-induced hearing loss (CIHL) remains unknown, an increasing body of research suggests that it is associated with excessive generation of intracellular reactive oxygen species (ROS) in the cochlea. Astaxanthin, a xanthophyll carotenoid, has powerful anti-oxidant, anti-inflammatory, and anti-apoptotic properties based on its unique cell membrane function, diverse biological activities, and ability to permeate the blood-brain barrier. In this review, we summarize the role of ROS in CIHL and the effect of astaxanthin on inhibiting ROS production. We focus on investigating the mechanism of action of astaxanthin in suppressing excessive production of ROS.

The Role of Redox Dysregulation in the Effects of Prenatal Stress on Embryonic Interneuron Migration

Maternal stress during pregnancy is associated with increased risk of psychiatric disorders in offspring, but embryonic brain mechanisms disrupted by prenatal stress are not fully understood. Our lab has shown that prenatal stress delays inhibitory neural progenitor migration. Here, we investigated redox dysregulation as a mechanism for embryonic cortical interneuron migration delay, utilizing direct manipulation of pro- and antioxidants and a mouse model of maternal repetitive restraint stress starting on embryonic day 12. Time-lapse, live-imaging of migrating GAD67GFP+ interneurons showed that normal tangential migration of inhibitory progenitor cells was disrupted by the pro-oxidant, hydrogen peroxide. Interneuron migration was also delayed by in utero intracerebroventricular rotenone. Prenatal stress altered glutathione levels and induced changes in activity of antioxidant enzymes and expression of redox-related genes in the embryonic forebrain. Assessment of dihydroethidium (DHE) fluorescence after prenatal stress in ganglionic eminence (GE), the source of migrating interneurons, showed increased levels of DHE oxidation. Maternal antioxidants (N-acetylcysteine and astaxanthin) normalized DHE oxidation levels in GE and ameliorated the migration delay caused by prenatal stress. Through convergent redox manipula-tions, delayed interneuron migration after prenatal stress was found to critically involve redox dysregulation. Redox biology during prenatal periods may be a target for protecting brain development.

Astaxanthin exerts protective effects similar to bexarotene in Alzheimer's disease by modulating amyloid-beta and cholesterol homeostasis in blood-brain barrier endothelial cells

The pathogenesis of Alzheimer's disease (AD) is characterized by overproduction, impaired clearance, and deposition of amyloid-β peptides (Aβ) and connected to cholesterol homeostasis. Since the blood-brain barrier (BBB) is involved in these processes, we investigated effects of the retinoid X receptor agonist, bexarotene (Bex), and the peroxisome proliferator-activated receptor α agonist and antioxidant, astaxanthin (Asx), on pathways of cellular cholesterol metabolism, amyloid precursor protein processing/Aβ production and transfer at the BBB in vitro using primary porcine brain capillary endothelial cells (pBCEC), and in 3xTg AD mice. Asx/Bex downregulated transcription/activity of amyloidogenic BACE1 and reduced Aβ oligomers and ~80 kDa intracellular 6E10-reactive APP/Aβ species, while upregulating non-amyloidogenic ADAM10 and soluble (s)APPα production in pBCEC. Asx/Bex enhanced Aβ clearance to the apical/plasma compartment of the in vitro BBB model. Asx/Bex increased expression levels of ABCA1, LRP1, and/or APOA-I. Asx/Bex promoted cholesterol efflux, partly via PPARα/RXR activation, while cholesterol biosynthesis/esterification was suppressed. Silencing of LRP-1 or inhibition of ABCA1 by probucol reversed Asx/Bex-mediated effects on levels of APP/Aβ species in pBCEC. Murine (m)BCEC isolated from 3xTg AD mice treated with Bex revealed elevated expression of APOE and ABCA1. Asx/Bex reduced BACE1 and increased LRP-1 expression in mBCEC from 3xTg AD mice when compared to vehicle-treated or non-Tg treated mice. In parallel, Asx/Bex reduced levels of Aβ oligomers in mBCEC and Aβ species in brain soluble and insoluble fractions of 3xTg AD mice. Our results suggest that both agonists exert beneficial effects at the BBB by balancing cholesterol homeostasis and enhancing clearance of Aβ from cerebrovascular endothelial cells.

Lipid peroxidation in neurodegeneration

Neurodegenerative diseases have great social and economic impact and cause millions of deaths every year. The potential molecular mechanisms in these pathologies have been widely studied and implicate lipid peroxidation as an important factor in the development of neurodegenerative disorders such as Alzheimer's, Parkinson's and Huntington's diseases. Data indicates that pathologic mechanisms specifically involve ferroptosis and mitochondrial dysfunction. Here we review the molecular mechanisms related to the lipid peroxidation that involve the development of neurodegeneration, as well as the utility of some biomarkers in diagnosis, prognosis and evaluation of new therapies for neurodegenerative diseases.

Astaxanthin ameliorates scopolamine-induced spatial memory deficit via reduced cortical-striato-hippocampal oxidative stress

Alzheimer's disease is characterized by progressive disruption of cholinergic neurotransmission and impaired cognitive functions. In rodents, scopolamine has been used to induce cholinergic dysfunction resulting in cognitive impairments and an increment of oxidative stress in the brain. Here we tested whether oxidative stress can be attenuated via an antioxidant (astaxanthin) to rescue scopolamine-induced spatial memory. For this purpose, we administered either 0.9% saline (control), or scopolamine (SCP), or scopolamine plus astaxanthin (SCP + AST) to Swiss albino mice (ten weeks old; n = 20) for 28 consecutive days and subsequently examined animals' locomotor activity, spatial learning, and memory performance. The mice were then euthanized and prefrontal cortex (PFC), striatum (ST), hippocampus (HP), and liver tissues were assayed for antioxidant enzymes, glutathione (GSH), superoxide dismutase (SOD), catalase (CAT), and nitric oxide (NO). The SCP group exhibited impaired spatial learning and significantly altered levels of antioxidant enzymes and NO in the PFC, ST, and HP. In contrast, SCP + AST treatment did not cause spatial learning deficits. Furthermore, this condition also showed unaltered levels of SOD and NO in the ST and HP. Taken together, our results show that scopolamine may interrupt the striatal-hippocampal cholinergic activity resulting in impaired spatial memory. At the same time, these impairments are extinguished with astaxanthin by preventing oxidative damage in the striatal-hippocampal cholinergic neurons. Therefore, we suggest astaxanthin as a potential treatment to slow the onset or progression of cognitive dysfunctions that are elicited by abnormal cholinergic neurotransmission in Alzheimer's disease.

Levocarnitine Improves AlCl3-Induced Spatial Working Memory Impairment in Swiss albino Mice

Background: Aluminum, a neurotoxic substance, causes oxidative stress induced-neurodegenerative diseases. Several lines of evidence suggest that levocarnitine has an antioxidant effect and also plays an important role in beta-oxidation of fatty acids. However, the role of levocarnitine in aluminum-induced neurotoxicity has not been well documented. Here we aimed to investigate the effect of levocarnitine on aluminum chloride (AlCl₃)-induced oxidative stress and memory dysfunction.

Methods: Male Swiss albino mice (n = 30) were treated with either control (saline) or AlCl₃ or AlCl₃ plus levocarnitine or levocarnitine or astaxanthin plus AlCl₃ or astaxanthin alone. The spatial working memory was determined by radial arm maze (RAM). In addition, we measured the lipid peroxidation (MDA), glutathione (GSH), advanced oxidation of protein products (AOPP), nitric oxide (NO) and activity of superoxide dismutase (SOD) in the various brain regions including prefrontal cortex (PFC), striatum (ST), parietal cortex (PC), hippocampus (HIP) hypothalamus (HT) and cerebellum (CB). We used astaxanthin as a standard antioxidant to compare the antioxidant activity of levocarnitine.

Results: The RAM data showed that AlCl₃ treatment (50 mg/kg) for 2 weeks resulted in a significant deficit in spatial learning in mice. Moreover, aluminum exposure significantly (p < 0.05) increased the level of oxidative stress markers such as MDA, GSH, AOPP and NO in the various brain regions compared to the controls. In addition, combined administration of levocarnitine and AlCl₃ significantly (p < 0.05) lowered the MDA, AOPP, GSH and NO levels in mice.

Conclusion: Our results demonstrate that levocarnitine could serve as a potential therapeutic agent in the treatment of oxidative stress associated diseases as well as in memory impairment.

Astaxanthin supplementation modulates cognitive function and synaptic plasticity in young and aged mice

The incidence of neurodegenerative disorders and cognitive impairment is increasing. Rising prevalence of age-related medical conditions is associated with a dramatic economic burden; therefore, developing strategies to manage these health concerns is of great public health interest. Nutritionally based interventions have shown promise in treatment of these age-associated conditions. Astaxanthin is a carotenoid with reputed neuroprotective properties in the context of disease and injury, while emerging evidence suggests that astaxanthin may also have additional biological activities relating to neurogenesis and synaptic plasticity. Here, we investigate the potential for astaxanthin to modulate cognitive function and neural plasticity in young and aged mice. We show that feeding astaxanthin to aged mice for 1 month improves performance on several hippocampal-dependent cognitive tasks and increases long-term potentiation. However, we did not observe an alteration in neurogenesis, nor did we observe a change in microglial-associated IBA1 immunostaining. This demonstrates the potential for astaxanthin to modulate neural plasticity and cognitive function in aging.

Astaxanthin Attenuates Environmental Tobacco Smoke-Induced Cognitive Deficits: A Critical Role of p38 MAPK

Increasing evidence indicates that environmental tobacco smoke (ETS) impairs cognitive function and induces oxidative stress in the brain. Recently, astaxanthin (ATX), a marine bioactive compound, has been reported to ameliorate cognitive deficits. However, the underlying pathogenesis remains unclear. In this study, ATX administration (40 mg/kg and 80 mg/kg, oral gavage) and cigarette smoking were carried out once a day for 10 weeks to investigate whether the p38 MAPK is involved in cognitive function in response to ATX treatment in the cortex and hippocampus of ETS mice. Results indicated that ATX administration improved spatial learning and memory of ETS mice (p < 0.05 or p < 0.01). Furthermore, exposure to ATX prevented the increases in the protein levels of the p38mitogen-activated protein kinase (p38 MAPK; p < 0.05 or p < 0.01) and nuclear factor-kappa B (NF-κB p65; p < 0.05 or p < 0.01), reversed the decreases in the mRNA and protein levels of synapsin I (SYN) and postsynaptic density protein 95 (PSD-95) (all p < 0.05 or p < 0.01). Moreover, ATX significantly down-regulated the increased levels of pro-inflammatory cytokines including interleukin-6 (IL-6) and tumor necrosis factor (TNF-α) (all p < 0.05 or p < 0.01). Meanwhile, the increased level of malondialdehyde (MDA) and the decreased activities of superoxide dismutase (SOD), glutathione (GSH), and catalase (CAT) were suppressed after exposure to ATX (all p < 0.05 or p < 0.01). Also, the results of the molecular docking study of ATX into the p38 MAPK binding site revealed that its mechanism was possibly similar to that of PH797804, a p38 MAPK inhibitor. Therefore, our results indicated that the ATX might be a critical agent in protecting the brain against neuroinflammation, synaptic plasticity impairment, and oxidative stress in the cortex and hippocampus of ETS mice.

Effect of Coenzyme Q10 Supplementation on Testosterone

Enhancing testosterone production in males is a continuous research direction for many scientists in the field, due to its role as a principal sex hormone and as a crucial modulator of well-being and general health in humans. Since 1978, there have been more than 30 studies that have connected coenzyme Q₁₀ and testosterone. Such a link is attributable to the vigorous biological role of coenzyme Q₁₀ as a crucial member in the energy production route in humans and animals, which is thought to have a positive influence on testosterone production, and hence on infertility, particularly male infertility. However, this connection has not yet been deliberated. The present work systematically reviews and summarizes the influence of coenzyme Q₁₀ supplementation on testosterone. To accomplish this purpose, the Scopus, PubMed, and Web of Science databases were searched using the keywords “coenzyme Q₁₀” versus “testosterone” for English language papers from November 1978 through October 2018. Relevant articles were also discussed and included to address an integral discussion. In summary, to date the studies conducted on human males reveal insignificant effects of coenzyme Q₁₀ supplementation on testosterone. Similarly, rather than the reproductive toxicity studies, the studies conducted on animals did not show any positive influence of coenzyme Q₁₀ on testosterone. However, coenzyme Q₁₀ supplementation was found to ameliorate the reduction in testosterone induced by chemical reproductive toxicants, mainly by neutralizing the damaging effect of the generated free radicals. However, collectively these findings require further confirmation by additional research studies.

Role of astaxanthin in the modulation of brain-derived neurotrophic factor and spatial learning behavior in perinatally undernourished Wistar rats

Objective: Maternal health and nutrition during the perinatal period is the predominant factor influencing the functional development of the brain. Maternal malnutrition during the perinatal period causes retardation of brain development. The current study investigates the role of Astaxanthin (AsX) in spatial learning and memory and BDNF in perinatally undernourished Wistar rats.Methods: The albino wistar rats were perinatally undernourished and administered with different dosages of AsX. The spatial learning and memory performance and BDNF level were assessed. Data were collected and analysed.Results: The % Correct choice during the acquisition phase, performance at the end of the acquisition phase and the mean BDNF level at the Hippocampus, Cerebellum, and Cerebral cortex showed significant decline (P<0.001) in the PUN group and significantly high (P<0.001) in the PUNA2 group compared to the control. However, the mean RME and mean WME during different days of the acquisition phase were significantly high (P<0.001) in the PUN group and insignificant (P>0.05) in PUNA2 compared to the control.Discussion: The results showed that AsX effectively modulated the cognitive deficit that occurred in perinatally undernourished rats. This can be attributed to BDNF upregulation as evidenced by the significant increase of the BDNF level.

Dietary astaxanthin can accumulate in the brain of rats

We evaluated the distribution of astaxanthin in rat brains after a single dose administration and after feeding 0.1% astaxanthin diet for 5 days. Astaxanthin was detected in the hippocampus and cerebral cortex 4 and 8 h after a single dose. Astaxanthin concentration in rat brains was higher after consumption of astaxanthin diet for 5 days than after a single dose.

Synergistic Effect of Quercetin and α-Lipoic Acid on Aluminium Chloride Induced Neurotoxicity in Rats

Objectives

The present study was carried out to study the protective effects of quercetin and α-lipoic acid alone and in combination against aluminum chloride induced neurotoxicity in rats.

Materials and Methods

The study consisted of eight groups, namely, Group 1: control rats, Group 2: rats receiving aluminium chloride 7 mg/kg body weight intraperitoneal route (i.p) for two weeks, Group 3: rats receiving quercetin 50 mg/kg body weight i.p. for two weeks, Group 4: rats receiving quercetin 50 mg/kg body weight followed by aluminium chloride 7 mg/kg body weight i.p. for two weeks, Group 5: rats receiving α-lipoic acid 20 mg/kg body weight i.p. for two weeks, Group 6: rats receiving lipoic acid 20 mg/kg body weight followed by aluminium chloride 7 mg/kg body weight i.p. for two weeks, Group 7: rats receiving α-lipoic acid 20 mg/kg body weight and quercetin 50 mg/kg body weight i.p. for two weeks, and Group 8: rats receiving α-lipoic acid 20 mg/kg body weight and quercetin 50 mg/kg body weight followed by aluminium chloride 7 mg/kg body weight i.p. for two weeks. The animals were killed after 24 hours of the last dose by cervical dislocation.

Results

Aluminium chloride treatment of rats resulted in significant increases in lipid peroxidation, protein carbonyl levels, and acetylcholine esterase activity in the brain. This was accompanied with significant decreases in reduced glutathione, activities of the glutathione reductase, and superoxide dismutase. Pretreatment of AlCl₃ exposed rats to either quercetin or α-lipoic acid also restored altered lipid peroxidation and superoxide dismutase to near normal levels. Quercetin or α-lipoic acid pretreatment of AlCl₃ exposed rats improved the protein carbonyl and reduced glutathione, glutathione reductase, and acetylcholine esterase activities in rat brains towards normal levels. Combined pretreatment of AlCl3 exposed rats with quercetin and α-lipoic acid resulted in a tendency towards normalization of most of the parameters.

Conclusions

Quercetin and α-lipoic acid complemented each other in protecting the rat brain against oxidative stress induced by aluminium chloride.

Astaxanthin is neuroprotective in an aged mouse model of Parkinson's disease

Parkinson's disease (PD) is the second most common neurodegenerative disorder and prevalence increases with age. Normal physiological changes that occur during the aging process reflect the pathological characteristics of Parkinson's disease. It is also recognized that age related changes significantly interact with the pathological mechanisms that underlie the neurodegeneration in PD and perpetuate the disease process. Despite the fact that aging is considered to be a primary risk factor for developing PD, the use of aged animal models are still under-utilized in pre-clinical research, thus reducing the translatability of experimental findings. Here, we use a natural compound astaxanthin (AXT) with multiple biological activities to attenuate neurotoxicity in a mouse model of Parkinson's disease in both young and aged mice. We observed that AXT preserved neurons in the substantia nigra of both young and aged mice that were exposed to the MPTP neurotoxin. However, AXT was less efficacious in the aged animals, as AXT was not able to protect against the MPTP induced loss of tyrosine hydroxylase (TH) throughout the aged nigro-striatal circuit. This disparity in the neuroprotective effect of AXT suggests that aging is a critical factor to consider during the development of novel therapeutics for neurodegenerative diseases and should be more rigorously evaluated in preclinical models.

Astaxanthin alleviated acute lung injury by inhibiting oxidative/nitrative stress and the inflammatory response in mice

The purpose of the present study was to assess the effect of astaxanthin (ASX) treatment on the acute lung injury (ALI) induced by cecal ligation and puncture (CLP) in mice. Mice were randomly allocated into the following groups: (1) the saline control group, in which mice were given saline before sham operation; (2) the ASX control group, in which mice received ASX before sham operation; (3) the ALI group, in which mice were given saline before CLP operation; and (4) the ALI+ASX group, in which mice received ASX before CLP operation. ASX was dissolved in olive oil and administrated by oral gavage for 14days consecutively before the CLP or sham operation. In experiment 1, Kaplan-Meier survival analysis was conducted for 72h after CLP. In experiment 2, blood, bronchoalveolar lavage fluid (BALF) and lung tissues were collected at 24h after the CLP or sham operation to determine the severity of lung injury. The results showed that ASX treatment could significantly decrease the CLP-induced mortality rate in mice. Meanwhile, ASX treatment significantly attenuated CLP-induced lung histopathological injury, inflammatory infiltration, total protein and albumin concentration, and total cell and neutrophil counts in the BALF. Furthermore, ASX treatment alleviated oxidative/nitrative stress, inflammation levels and pulmonary apoptosis in lung tissues. In addition, ASX treatment markedly down-regulated the expression of inducible nitric oxide synthase (i-NOS), nitrotyrosine (NT) and nuclear factor-kappa B (NF-Κb) P65 in the lung tissues compared with that in the ALI group. Astaxanthin treatment had markedly protective effect against ALI in mice, and the potential mechanism is associated with its ability to inhibit the inflammatory response, oxidative/nitrative stress, and pulmonary apoptosis, as well as down-regulate NF-κB P65 expression.

Astaxanthin mitigates cobalt cytotoxicity in the MG-63 cells by modulating the oxidative stress

Background

With the re-popularity of metal-on-metal (MoM) bearing in recent years, the cobalt toxicity has been a cause for concern in the total hip replacement surgery by both physicians and patients.

Methods

MG-63 cell line was cultured in vitro and incubated with cobalt (II) chloride (CoCl₂) and/or with astaxanthin (ASX) for 24 h. MTT assay was conducted to evaluate the cell viability after cobalt exposure and ASX treatment. Fluorescence-activated cell sorting (FACS) analysis was performed to examine the reactive oxygen species (ROS) level. Quantitative real-time polymerase chain reaction (PCR) was adopted to determine the mRNA levels of related targets. And western blot analysis was used to examine the protein expressions. One-way ANOVA with posttest Newman-Keuls multiple comparisons was adopted to analysis all the obtained data.

Results

In the current study, ASX exhibited significant protective effect against the Co(II)-induced cytotoxicity in MG-63 cell line. We also found that ASX protected the cells against Co-induced apoptosis by regulating the expression of Bcl-2 family proteins. Besides, heme oxygenase 1 (HO-1) could be activated by Co exposure; ASX treatment significantly inhibited HO-1 activation, suppressing the oxidative stress induced by Co exposure. Moreover, c-Jun N-terminal Kinase (JNK) phosphorylation was shown to participate in the signaling pathway of the protective effect of ASX. However, knockdown of JNK expression by siRNA transfection or JNK inhibitor SP600125 treatment did not affect the protective effect of ASX against cobalt cytotoxicity in MG-63 cells.

Conclusions

ASX mitigated cobalt cytotoxicity in the MG-63 cells by modulating the oxidative stress. And ASX could be a promising therapy against cobalt toxicity in the hip articulation surgery.

Electronic supplementary material

The online version of this article (doi:10.1186/s40360-017-0166-1) contains supplementary material, which is available to authorized users.

Neuroprotective mechanisms of astaxanthin: a potential therapeutic role in preserving cognitive function in age and neurodegeneration

Astaxanthin (AXT) is a carotenoid with multiple health benefits. It is currently marketed as a health supplement and is well known for its antioxidant capacity. Recent evidence has emerged to suggest a broad range of biological activities. The interest in this compound has increased dramatically over the last few years and many studies are now applying this molecule across many disease models. Results from the current research are beginning to come together to suggest neuroprotective properties including anti-inflammatory, anti-apoptotic, and antioxidant effects, as well as the potential to promote or maintain neural plasticity. These emergent mechanisms of actions implicate AXT as a promising therapeutic agent for neurodegenerative disease. This review will examine and extrapolate from the recent literature to build support for the use of AXT in mitigating neuropathy in normal aging and neurodegenerative disease.