Aflatoxin B1 reduces non-enzymatic antioxidant defenses and increases protein kinase C activation in the cerebral cortex of young rats

Neurotoxic mechanisms of mycotoxins: Focus on aflatoxin B1 and T-2 toxin

Aflatoxin B1 (AFB1) and T-2 toxin are commonly found in animal feed and stored grain, posing a serious threat to human and animal health. Mycotoxins can penetrate brain tissue by compromising the blood-brain barrier, triggering oxidative stress and neuroinflammation, and leading to oxidative damage and apoptosis of brain cells. The potential neurotoxic mechanisms of AFB1 and T-2 toxin were discussed by summarizing the relevant research reports from the past ten years. AFB1 and T-2 toxin cause neuronal damage in the cerebral cortex and hippocampus, leading to synaptic transmission dysfunction, ultimately impairing the nervous system function of the body. The toxic mechanism is related to excessive reactive oxygen species (ROS), oxidative stress, mitochondrial dysfunction, apoptosis, autophagy, and an exaggerated inflammatory response. After passing through the blood-brain barrier, toxins can directly affect glial cells, alter the activation state of microglia and astrocytes, thereby promoting brain inflammation, disrupting the blood-brain barrier, and influencing the synaptic transmission process. We discussed the diverse effects of various concentrations of toxins and different modes of exposure on neurotoxicity. In addition, toxins can also cross the placental barrier, causing neurotoxic symptoms in offspring, as demonstrated in various species. Our goal is to uncover the underlying mechanisms of the neurotoxicity of AFB1 and T-2 toxin and to provide insights for future research, including investigating the impact of mycotoxins on interactions between microglia and astrocytes.

Aflatoxin B1 induces infertility, fetal deformities, and potential therapies

Aflatoxin B1 (AFB1) is a subsidiary poisonous metabolite, archetypally spawned by Aspergillus flavus and A. parasiticus, which are often isolated in warm or tropical countries across the world. AFB1 is capable of disrupting the functioning of several reproductive endocrine glands by interrupting the enzymes and their substrates that are liable for the synthesis of various hormones in both males and females. In men, AFB1 is capable of hindering testicular development, testicular degeneration, and reduces reproductive capabilities. In women, a direct antagonistic interaction of AFB1 with steroid hormone receptors influencing gonadal hormone production of estrogen and progesterone was responsible for AFB1-associated infertility. AFB1 is potentially teratogenic and is responsible for the development of malformation in humans and animals. Soft-tissue anomalies such as internal hydrocephalus, microphthalmia, cardiac defects, augmented liver lobes, reproductive changes, immune modifications, behavioral changes and predisposition of animals and humans to neoplasm development are AFB1-associated anomalies. Substances such as esculin, selenium, gynandra extract, vitamins C and E, oltipraz, and CDDO-Im are potential therapies for AFB1. Thus, this review elucidates the pivotal pathogenic roles of AFB1 in infertility, fetal deformities, and potential therapies because AFB1 toxicity is a key problem globally.

Cellular and molecular mechanisms of aflatoxin B1-mediated neurotoxicity: The therapeutic role of natural bioactive compounds

Aflatoxin B1 (AFB1), a dietary toxin from the mold Aspergillus species, is well acknowledged to elicit extra-hepatic toxicity in both animals and humans. The neurotoxicity of AFB1 has become a global public health concern. Contemporary research on how AFB1 enters the brain to elicit neuronal dysregulation leading to noxious neurological outcomes has increased greatly in recent years. The current review discusses several neurotoxic outcomes and susceptible targets of AFB1 toxicity at cellular, molecular and genetic levels. Specifically, neurotoxicity studies involving the use of brain homogenates, neuroblastoma cell line IMR-32, human brain microvascular endothelial cells, microglial cells, and astrocytes, as well as mammalian and non-mammalian models to unravel the mechanisms associated with AFB1 exposure are highlighted. Further, some naturally occurring bioactive compounds with compelling therapeutic effects on AFB1-induced neurotoxicity are reviewed. In conclusion, available data from literature highlight AFB1 as a neurotoxin and its possible pathological contribution to neurological disorders. Further mechanistic studies aimed at discovering and developing effective therapeutics for AFB1 neurotoxicity is warranted.

Pitaya Juice Consumption Protects against Oxidative Damage Induced by Aflatoxin B1

Mycotoxins are toxic fungal metabolites and are responsible for contaminating several foods. The intake of foods contaminated by these substances is related to hepatotoxicity and carcinogenic effects, possibly due to increasing oxidative stress. The current study evaluated Pitaya fruit juice's antioxidant effects on oxidative damage aflatoxin B1 (AFB1)-induced. Rats received 1.5 mL of Pitaya juice via gavage (for 30 days), and on the 31st day, they received AFB1 (250 µg/kg, via gavage). Forty-eight hours after the AFB1 dose, rats were euthanized for dosages of alanine transaminase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP); dosage of oxidative markers (thiobarbituric acid reactive species (TBARS), reactive species (RS)) and antioxidant defenses (catalase (CAT), superoxide dismutase (SOD), Glutathione S-transferase (GST) activities and Glutathione (GSH)) levels in the liver; and detection of Heat shock protein 70 (Hsp-70) and nuclear factor- erythroid 2-related factor 2 (Nrf2) immunocontent in the liver. Our results indicated that the Pitaya juice reduced ALP activity. Further, rats exposed to AFB1 experienced liver damage due to the increase in TBARS, RS, and Hsp-70 and the reduction in CAT, GSH, and Nrf2. Pitaya juice could, however, protect against these damages. Finally, these results indicated that pre-treatment with Pitaya juice was effective against the oxidative damage induced. However, other aspects may be elucidated in the future to discover more targets of its action against mycotoxicosis.

Intermittent Exposure to Aflatoxin B1 Did Not Affect Neurobehavioral Parameters and Biochemical Markers of Oxidative Stress

Aflatoxin B1 (AFB1) is the most common toxic mycotoxin that contaminates food. The treatment of its intoxication and the management of contaminations are a constant subject of health agendas worldwide. However, such efforts are not always enough to avoid population intoxication. Our objective was to investigate whether intermittent exposure to AFB1 would cause any impairment in biochemical and behavioral parameters, intending to simulate an irregular consumption. Male Wistar rats received four AFB1 administrations (250 μg/kg) by intragastric route separated by a 96-h interval. Toxicity was evaluated using behavioral tests (open field, object recognition, nest construction, marble burying, and splash test), biochemical markers of oxidative stress (cerebral cortex, hippocampus, liver, and kidneys), and plasma parameters of hepatic and renal functions. The intermittent exposure caused no modification in body weight gain as well as in organ weight. Both control and AFB1 groups presented similar profiles of behavior to all tests performed. Furthermore, AFB1 administrations alter neither antioxidant defenses nor markers of oxidation in all assayed tissues and in the plasma markers of hepatic and renal functions. Therefore, AFB1 intermittent administration did not cause its common damage from exposure to this toxicant, which must be avoided, and additional studies are required.

Repeated co-exposure to aflatoxin B1 and aspartame disrupts the central nervous system homeostasis: Behavioral, biochemical, and molecular insights

Several studies demonstrated the toxicity of aspartame (ASP) and aflatoxin B₁ (AFB₁ ) in preclinical models. Although the majority of these reports assessed the toxic effects of each substance separately, their concomitant exposure and hazardous consequences are scarce. Importantly, the deleterious effects at the central nervous system caused by ASP and AFB₁ co-exposure are rarely addressed. We evaluated if concomitant exposure to AFB₁ and ASP would cause behavioral impairment and alteration in oxidative status of the brain in male rats. Animals received once a day for 14 days AFB₁ (250 µg/kg, intragastric gavage [i.g.]), ASP (75 mg/kg, i.g.), or both substances (association). On day 14, they were subjected to behavioral evaluation, and biochemical and molecular parameters of oxidative status were measured in the cerebral cortex and hippocampus. In the open field test, AFB₁ and combination treatments modified the motor, exploratory, and grooming behavior. In the splash test, all treatments caused a reduction in grooming time compared to the control group. An increase in thiobarbituric acid-reactive substances content induced by AFB₁ and combination treatments was observed. The antioxidant defenses (vitamin C, nonprotein sulfhydryl, and ferric reducing antioxidant power) were impaired in all groups compared to control. Regarding molecular evaluation, mitochondrial superoxide dismutase-2 immunoreactivity decreased after AFB₁ or ASP exposition in the hippocampus. Thus, co-exposure to ASP and AFB₁ was potentially more toxic because it aggravated behavioral impairments and oxidative status disbalance in comparison to the groups that received only ASP or AFB₁ . Therefore, our data suggest that those substances caused a disruption in brain homeostasis.

Neurobehavioral and biochemical responses to artemisinin-based drug and aflatoxin B1 co-exposure in rats

Populations in malaria endemic areas are frequently exposed to mycotoxin-contaminated diets. The possible toxicological outcome of co-exposure to dietary aflatoxin B₁ (AFB₁) and artemisinin-based combination therapy warrants investigation to ascertain amplification or attenuation of cellular injury. Here, we investigated the neurobehavioral and biochemical responses associated with co-exposure to anti-malarial drug coartem, an artemether-lumefantrine combination (5 mg/kg body weight, twice a day and 3 days per week) and AFB₁ (35 and 70 µg/kg body weight) in rats. Motor deficits, locomotor incompetence, and anxiogenic-like behavior induced by low AFB₁ dose were significantly (p < 0.05) assuaged by coartem but failed to rescue these behavioral abnormalities in high AFB₁-dosed group. Coartem administration did not alter exploratory deficits typified by reduced track plot densities and greater heat map intensity in high AFB₁-dosed animals. Furthermore, the reduction in cerebral and cerebellar acetylcholinesterase activity, anti-oxidant enzyme activities, and glutathione and thiol levels were markedly assuaged by coartem administration in low AFB₁ group but not in high AFB₁-dosed animals. The significant attenuation of cerebral and cerebellar oxidative stress indices namely reactive oxygen and nitrogen species, xanthine oxidase activity, and lipid peroxidation by coartem administration was evident in low AFB₁ group but not high AFB₁ dose. Although coartem administration abated nitric oxide level, activities of myeloperoxidase, caspase-9, and caspase-3 in animals exposed to both doses of AFB₁, these indices were significantly higher than the control. Coartem administration ameliorated histopathological and mophometrical changes due to low AFB₁ exposure but not in high AFB₁ exposure. In conclusion, contrary to AFB₁ alone, behavioral and biochemical responses were not altered in animals singly exposed to coartem. Co-exposure to coartem and AFB₁ elicited no additional risk but partially lessened neurotoxicity associated with AFB₁ exposure.

Aflatoxin G1 exposure altered the expression of BDNF and GFAP, histopathological of brain tissue, and oxidative stress factors in male rats

Background and purpose

Aflatoxins are highly toxic compounds that can cause acute and chronic toxicity in humans and animals. This study aimed to evaluate the expression of BDNF and GFAP, histopathological changes, and oxidative stress factors in brain tissue exposed to aflatoxin G1 (AFG1) in male rats.

Experimental approach

Twenty-eight male Wistar rats were used. Animals were randomly divided into 4 groups of 7 each. The control group received 0.2 mL of corn oil and the treatment groups were exposed to AFG1 (2 mg/kg) intra-peritoneally for 15, 28, and 45 days. The tissue was used for histopathological studies, and the level of TAC, SOD, and MDA, and the expression of BDNF and GFAP genes were evaluated.

Findings/Results

Real-time PCR results showed that AFG1 increased GFAP expression and decreased BDNF expression in AFG1-treated groups compared to the control group. The tissue level of TAC and SOD over time in the groups receiving AFG1 significantly decreased and the tissue level of MDA increased compared to the control group. Histopathological results showed that AFG1 can cause cell necrosis, a reduction of the normal cells number in the hippocampal region of CA1, cerebral edema, shrinkage of nerve cells, formation of space around neuroglia, and diffusion of gliosis in the cerebral cortex after 45 days.

Conclusion and implication

AFG1, by causing pathological complications in cortical tissue, was able to affect the exacerbation of nerve tissue damage and thus pave the way for future neurological diseases.

May phytophenolics alleviate aflatoxins-induced health challenges? A holistic insight on current landscape and future prospects

The future GCC-connected environmental risk factors expedited the progression of nCDs. Indeed, the emergence of AFs is becoming a global food security concern. AFs are lethal carcinogenic mycotoxins, causing damage to the liver, kidney, and gastrointestinal organs. Long-term exposure to AFs leads to liver cancer. Almost a variety of food commodities, crops, spices, herbaceous materials, nuts, and processed foods can be contaminated with AFs. In this regard, the primary sections of this review aim to cover influencing factors in the occurrence of AFs, the role of AFs in progression of nCDs, links between GCC/nCDs and exposure to AFs, frequency of AFs-based academic investigations, and world distribution of AFs. Next, the current trends in the application of PPs to alleviate AFs toxicity are discussed. Nearly, more than 20,000 published records indexed in scientific databases have been screened to find recent trends on AFs and application of PPs in AFs therapy. Accordingly, shifts in world climate, improper infrastructures for production/storage of food commodities, inconsistency of global polices on AFs permissible concentration in food/feed, and lack of the public awareness are accounting for a considerable proportion of AFs damages. AFs exhibited their toxic effects by triggering the progression of inflammation and oxidative/nitrosative stress, in turn, leading to the onset of nCDs. PPs could decrease AFs-associated oxidative stress, genotoxic, mutagenic, and carcinogenic effects by improving cellular antioxidant balance, regulation of signaling pathways, alleviating inflammatory responses, and modification of gene expression profile in a dose/time-reliant fashion. The administration of PPs alone displayed lower biological properties compared to co-treatment of these metabolites with AFs. This issue might highlight the therapeutic application of PPs than their preventative content. Flavonoids such as quercetin and oxidized tea phenolics, curcumin and resveratrol were the most studied anti-AFs PPs. Our literature review clearly disclosed that considering PPs in antioxidant therapies to alleviate complications of AFs requires improvement in their bioavailability, pharmacokinetics, tissue clearance, and off-target mode of action. Due to the emergencies in the elimination of AFs in food/feedstuffs, further large-scale clinical assessment of PPs to decrease the consequences of AFs is highly required.

Effects of probiotic supplementation on very low dose AFB1-induced neurotoxicity in adult male rats

AIMS

Aflatoxin B1 (AFB1) is the most toxic and common form of AF found in food and feed. Although AFB1 exposure has toxic effects on many organs, studies on the brain are limited. Moreover, to the best of our knowledge, there is no study on the effect of probiotics on AFB1-induced neurotoxicity. Therefore, we aimed to evaluate the possible effects of probiotics on AFB1-induced neurotoxicity in the brain.

MAIN METHODS

Thirty-two adult male Wistar rats were divided into four groups: Vehicle (VEH), Probiotic (PRO) (2.5 × 10¹⁰ CFU/day VSL#3, orally), Aflatoxin B1 (AFB1) (25 μg/kg/week AFB1, orally), and Aflatoxin B1 + Probiotic (AFB1 + PRO) (2.5 × 10¹⁰ CFU/day VSL#3 + 25 μg/kg/week AFB1, orally). At the end of eight weeks, rats were behaviorally evaluated by the open field test, novel object recognition test, and forced swim test. Then, oxidative stress and inflammatory markers in brain tissues were analyzed. Next, brain sections were processed for Hematoxylin&Eosin staining and NeuN and GFAP immunostaining.

KEY FINDINGS

Probiotic supplementation tended to decrease oxidative stress and inflammatory markers compared to the AFB1 group. Besides, brain tissues had more normal histological structures in VEH, PRO, and AFB1 + PRO groups than in the AFB1 group. Moreover, in probiotic groups, GFAP immunoreactivity intensity was decreased, while NeuN-positive cell number increased in brain tissues compared to the AFB1 group.

SIGNIFICANCE

Probiotics seem to be effective at reducing the neurotoxic effects of AFB1. Thus, our study suggested that especially Bifidobacterium and Lactobacillus species can improve AFB1-induced neurotoxicity with their antioxidant and anti-inflammatory effects.

Aflatoxin B1 induces microglia cells apoptosis mediated by oxidative stress through NF-κB signaling pathway in mice spinal cords

Many studies have shown that aflatoxin B1 (AFB1) can cause cytotoxicity in numerous cells and organs induced by oxidative stress. However, the toxic effects and related mechanism of AFB1 on the microglia cells in the spinal cords have not been studied yet. Our results showed that AFB1 significantly reduced the number of microglia cells, increased the oxidants (malonaldehyde and hydrogen peroxide) but decreased the anti-oxidants (superoxide dismutase and total antioxidant capacity) in a dose dependent manner in mice spinal cords. In addition, AFB1 significantly increased the oxidative stress, promoted apoptosis and cell cycle arrest in G2-M phase, and activated NF-κB phosphorylation in BV2 microglia cells. However, the addition of active oxygen scavenger N-acetylcysteine can significantly reduce the ROS production, improve cell cycle arrest, reduce apoptosis, and the expression of phosphorylated NF-κB in BV2 microglia cells. These results indicate that AFB1 induces microglia cells apoptosis through oxidative stress by activating NF-κB signaling pathway.

Hepatic susceptibility to oxidative damage after repeated concomitant exposure to aspartame and aflatoxin B1 in rats

The potential interactions among food additives/contaminants and the consequences to biological systems is a topic that is rarely addressed in scientific literature. Thus, the current study investigated if the combined administration of ASP and AFB₁ would impair hepatic and renal oxidative status. Male Wistar rats received during 14 days once a day ASP (75 mg/Kg) and/or AFB₁ (250 µg/Kg) through intragastric route. At the end of experimental protocol, samples of liver and kidneys were collected for assessing biochemical markers of oxidative status. In the hepatic tissue, the treatment with a single substance (ASP or AFB₁) caused an increase in TBARS levels, and a reduction in non-enzymatic antioxidant defenses (Vit C and NPSH levels and FRAP test). In the kidneys, TBARS levels were increased only in the group that received ASP + AFB₁. The association reduced NPSH content, while the treatment with AFB₁ reduced the FRAP levels. GST and CAT activities were increased in all treatments. Overall, ASP and AFB1 association presented higher toxic effects to the tissues. To the best of our knowledge, this is the first study demonstrating that the associated use of both ASP and AFB1 induces more extensive injuries in comparison to the effects caused by each one alone. Therefore, these data demonstrated that concomitant exposure to ASP and AFB₁ potentiated their oxidative damage in hepatic tissue, suggesting that this organ is particularly sensitive to the toxic action induced by these substances.

Therapeutic potential of beta-caryophyllene against aflatoxin B1-Induced liver toxicity: biochemical and molecular insights in rats

Aflatoxin B1 (AFB1) is a mycotoxin highly toxic and carcinogenic to humans due to its potential to induce oxidative stress. The Beta-caryophyllene (BCP) have been highlighted for its broad spectrum of pharmacological effects. The present study aimed to investigate the beneficial effects of BCP against the susceptibility of hepatic and renal tissues to AFB1 toxicity, in biochemical parameters to assess organ function, tissue oxidation, and the immunocontent of oxidative and inflammatory proteins. Male Wistar rats was exposed to AFB1 (250 μg/kg, i.g.) and/or BCP (100 mg/kg, i.p.) for 14 successive days. It was found that exposure to AFB1 did not change the measured renal toxicity parameters. Also, AFB1 increased liver injury biomarkers (gamma glutamyl transferase and alkaline phosphatase) and reduced levels of non-enzymatic antioxidant defenses (ascorbic acid and non-protein thiol), however did not cause changes in the lipid peroxidation levels. Moreover, AFB1 interfered in oxidative pathway regulated by Kelch-like ECH-associated protein (Keap1)/nuclear factor (erythroid-derived 2)-like 2 (Nrf2), overacting Glutathione-S-Transferase (GST) activity. Lastly, a main effect of AFB1 on the total interleukin 1 beta (IL-1β) was observed. Remarkably, the associated treatment of AFB1 + BCP improved altered liver parameters. In addition, BCP and AFB1 + BCP groups showed an increase in the levels of inhibitor of nuclear factor kappa-B kinase subunit beta (IKKβ). Thus, these results indicated that BCP has potential protective effect against AFB1 induced hepatotoxicity.

The role of mycotoxins in neurodegenerative diseases: current state of the art and future perspectives of research

Mycotoxins are fungal metabolites that can cause various diseases in humans and animals. The adverse health effects of mycotoxins such as liver failure, immune deficiency, and cancer are well-described. However, growing evidence suggests an additional link between these fungal metabolites and neurodegenerative diseases. Despite the wealth of these initial reports, reliable conclusions are still constrained by limited access to human patients and availability of suitable cell or animal model systems. This review summarizes knowledge on mycotoxins associated with neurodegenerative diseases and the assumed underlying pathophysiological mechanisms. The limitations of the common in vivo and in vitro experiments to identify the role of mycotoxins in neurotoxicity and thereby in neurodegenerative diseases are elucidated and possible future perspectives to further evolve this research field are presented.

Autophagy up-regulated by MEK/ERK promotes the repair of DNA damage caused by aflatoxin B1

Aflatoxin B1 (AFB1), a kind of mycotoxin, exerts its cytotoxicity by increasing the oxidative damage of target organs, especially the liver. In vivo and in vitro experiments were carried out to elucidate the toxic mechanism of AFB1. The results of MTT, cloning-formation, flow cytometry, immunocytochemistry, Reverse transcription PCR (RT-PCR) and western blot showed that AFB1 activated NOX2 gp91 phox, inhibited proliferation and migration, and blocked cell cycle at G0/G1 period of HHL-5 cells. Autophagy promoted the repair of NOX2-dependent DNA damage. NOX2/gp91 phox mainly activates MEK/ERK pathway and then up-regulates autophagy. In vivo experiments have shown that AFB1 (0.75 mg/kg daily orally, 4 weeks) had no significant changes in the size and shape of the liver in mice. However, these treatments lead to structural abnormalities of hepatocytes and DNA damage. In summary, AFB1 caused intracellular oxidative stress and DNA damage, NOX2/gp91-phox activates the MEK/ERK pathway, and upregulated autophagy to promote the repair of DNA damage. We concluded that by increasing the level of autophagy, the ability of anti-AFB1 toxicity of liver can be increased.

Aflatoxicosis Dysregulates the Physiological Responses to Crowding Densities in the Marine Teleost Gilthead Seabream (Sparus aurata)

Several studies in fish have shown that aflatoxin B1 (AFB1) causes a disparity of species-dependent physiological disorders without compromising survival. We studied the effect of dietary administration of AFB1 (2 mg AFB1 kg^-1 diet) in gilthead seabream (Sparus aurata) juveniles in combination with a challenge by stocking density (4 vs. 40 g L^-1). The experimental period duration was ten days, and the diet with AFB1 was administered to the fish for 85 days prior to the stocking density challenge. Our results indicated an alteration in the carbohydrate and lipid metabolites mobilization in the AFB1 fed group, which was intensified at high stocking density (HSD). The CT group at HSD increased plasma cortisol levels, as expected, whereas the AFB1-HSD group did not. The star mRNA expression, an enzyme involved in cortisol synthesis in the head kidney, presented a ninefold increase in the AFB1 group at low stocking density (LSD) compared to the CT-LSD group. Adenohypophyseal gh mRNA expression increased in the AFB1-HSD but not in the CT-HSD group. Overall, these results confirmed that chronic AFB1 dietary exposure alters the adequate endocrinological physiological cascade response in S. aurata, compromising the expected stress response to an additional stressor, such as overcrowding.

Neuroprotective role of gallic acid in aflatoxin B1 -induced behavioral abnormalities in rats

The neurotoxic impact of dietary exposure to aflatoxin B₁ (AFB₁ ) is documented in experimental and epidemiological studies. Gallic acid (GA) is a triphenolic phytochemical with potent anticancer, anti-inflammatory, and antioxidant activities. There is a knowledge gap on the influence of GA on AFB₁ -induced neurotoxicity. This study probed the influence of GA on neurobehavioral and biochemical abnormalities in rats orally treated with AFB₁ per se (75 µg/kg body weight) or administered together with GA (20 and 40 mg/kg) for 28 uninterrupted days. Behavioral endpoints obtained with video-tracking software demonstrated significant (p < .05) abatement of AFB₁ -induced anxiogenic-like behaviors (increased freezing, urination, and fecal bolus discharge), motor and locomotor inadequacies, namely increased negative geotaxis and diminished grip strength, absolute turn angle, total time mobile, body rotation, maximum speed, and total distance traveled by GA. The improvement of exploratory behavior in animals that received both AFB₁ and GA was confirmed by track plots and heat maps appraisal. Abatement of AFB₁ -induced decreases in acetylcholinesterase activity, antioxidant status and glutathione level by GA was accompanied by a marked reduction in oxidative stress markers in the cerebellum and cerebrum of rats. Additionally, GA treatment abrogated AFB₁ -mediated decrease in interleukin-10 and elevation of inflammatory indices, namely tumor necrosis factor-α, myeloperoxidase activity, interleukin-1β, and nitric oxide. Further, GA treatment curtailed caspase-3 activation and histological injuries in the cerebral and cerebellar tissues. In conclusion, abatement of AFB₁ -induced neurobehavioral abnormalities by GA involves anti-inflammatory, antioxidant, and antiapoptotic mechanisms in rats.

Dietary vegetable choline improves hepatic health of Nile tilapia (Oreochromis niloticus) fed aflatoxin-contaminated diet

Aflatoxin B_{1 (}AFB₁) is one of the most important mycotoxins due to its hepatotoxic and carcinogenic effects on animals. The effect of dietary supplementation with vegetable choline (VC) at 400, 800, and 1200 mg/kg against the deleterious effects of AFB₁ (2 ppm/kg diet) in the liver of Nile tilapia (Oreochromis niloticus) was studied. The experimental period was 81 days, and the diet with VC was offered to the fish for 60 days prior to challenge with AFB₁. Diets with AFB₁ were tested in three replications and animals were analyzed at days 14 and 21 of dietary intake. The addition of VC to tilapia diet increased body weight (days 30 and 60 pre-challenge and day 21 post-challenge). The group fed aflatoxin-contaminated diet presented significantly reduced antioxidant enzymes and increased reactive oxygen species (ROS) levels, thiobarbituric acid reactive species (TBARS) levels, and protein carbonyl (PC) content in the liver. Dietary supplementation with VC at 800 and 1200 mg/kg demonstrated a significant protective effect, avoiding the increase of ROS, TBARS, and PC levels in the liver of tilapia from the aflatoxin contaminated groups. Thus, dietary VC supplementation may be used in tilapia to increase antioxidant status and reduce the negative effects caused by AFB₁ toxicity. Based on the findings, it is recommended to use VC as a food supplement for Nile tilapia in order to avoid AFB₁ toxication. In addition, decreased aflatoxin toxicity can be attributed to the VC antioxidant property.

Probabilistic dietary based estimation of the burden of aflatoxin-induced hepatocellular carcinoma among adult Malawians

The risk of aflatoxin-induced hepatocellular carcinoma (HCC) among adults (average body weight of 60 kg) in Malawi was assessed based on aflatoxin B1 (AFB1) exposure through groundnut and maize consumption, by Monte Carlo simulation. The risk (cases per year per 100,000 people) of aflatoxin-induced HCC was estimated based on the AFB1 exposures estimated by this study and hepatitis B virus infection prevalence published for Malawi. AFB1 exposures were estimated by probabilistically combining data of AFB1 contamination in 338 groundnut and 604 maize samples with data of per capita groundnut and maize consumption in 274 households. Aflatoxins in the samples were analysed using validated LC-MS/MS, HPLC and VICAM based methods. The groundnut and maize consumption survey was based on household expenditure technique. The simulated mean AFB1 exposures through consumption of groundnuts, maize, and combination thereof were 28±65, 42±174, and 71±211 ng/kg. body weight (bw)/day, respectively. The estimated HCC risks were 1.26±2.72, 1.86±6.66 and 3.10±6.85 cases per 100,000 persons per year, respectively. Further, hypothetical eradication of hepatitis B virus (HBV) reduced the risk of HCC by 78%. This reaffirms the need for integrating HBV vaccination in the fight of aflatoxin induced HCC.

Behavioural and biochemical effects of one-week exposure to aflatoxin B1 and aspartame in male Wistar rats

Food products are susceptible to contamination by mycotoxins, and aflatoxin B1 (AFB1) stands as the most toxic among them. AFB1 intoxication results in distinct signs, including widespread systemic toxicity. Aspartame (ASP) is an artificial sweetener used as a sugar substitute in many products, and compelling evidence indicates ASP can be toxic. Interestingly, mechanisms underlying ASP and AFB1 toxicity involve oxidative stress. In this context, concomitant use of ASP and AFB1 in a meal may predispose to currently unidentified behavioural and biochemical changes. Therefore, we evaluated the effect of AFB1 (250 μg/kg, intragastrically (i.g.)) and/or ASP (75 mg/kg, i.g.) exposure for 7 days on behavioural and biochemical markers of oxidative stress in male Wistar rats. AFB1 and/or ASP increased hepatic glutathione S-transferase (GST) activity when compared to controls. In the kidneys, increased GST activity was detected in AFB1 and AFB1+ASP groups. In addition, AFB1 and or ASP elicited behavioural changes in the open field, marble burying and splash tests, however no additive effects were detected. Altogether, present data suggest AFB1 and ASP predispose to anxiety- and obsessive-compulsive-like symptoms, as well as to enzymatic defence system imbalance in liver and kidney of Wistar rats.

Oxidative Stress in Extrahepatic Tissues of Rats Co-Exposed to Aflatoxin B1 and Low Protein Diet

Early life exposure to aflatoxin B1 (AFB1) and low protein diet through complementary foods during weaning is common in parts of Africa and Asia. This study evaluated the effect of co-exposure to AFB1 and low protein diet on the extrahepatic tissues of rats. Twenty-four three-week old weanling male albino rats were used for this study and were randomly assigned into four groups: group 1 served as control and was fed normal protein diet (20% protein), group 2 was fed low protein diet (5% protein), group 3 was fed normal protein diet + 40 ppb AFB1 while group 4 received low protein diet + 40 ppb AFB1, all for eight weeks. Afterward, biomarkers of anemia (packed cell volume (PCV), hemoglobin) and kidney function (urea, uric acid, and creatinine) were determined in the blood while biomarkers of oxidative stress were determined in the tissues spectrophotometrically. Co-exposure to AFB1 and low protein diet significantly (p < 0.05) decreased body weight gain and PCV, increased biomarkers of kidney functions and induced oxidative stress in the tissues studied. There was significant (p < 0.05) reduction in glutathione concentration while TBARS was significantly increased in the tissues. Co-exposure to AFB1 and low protein diet had additive effects on decreasing the weight gain and potentiation effect of kidney dysfunction in the rats. The co-exposure also decreased antioxidant enzymes and increased oxidant status in the tissues. Our results demonstrate that this co-exposure has deleterious health effects on extrahepatic tissues and should be a public health concern especially in developing countries where AFB1 contamination is common.