Potent Hepatocarcinogen Research Articles

Formation of hepatocyte cytoplasmic inclusions and their contribution to methylcarbamate-induced hepatocarcinogenesis in F344 rats.

Methylcarbamate (MC), a reaction product between dimethyl dicarbonate and ammonia or ammonium ion, is a potent hepatocarcinogen in F344 rats. Various genotoxicity tests have shown negative results for MC. Although previous studies have described the effects of MC on the liver, including the formation of characteristic basophilic cytoplasmic inclusions (CIs) in hepatocytes, the toxicological significance of CIs and their involvement in hepatocarcinogenesis remain unclear. In the current study, to elucidate the mechanisms of MC hepatocarcinogenesis, we examined hepatotoxicity and genotoxicity after 4 weeks of administration of MC using gpt delta rats with an F344 genetic background as a reporter gene transgenic animal model. Histopathologically, single-cell necrosis, karyomegaly, and the formation of CIs positive for Feulgen staining were observed in hepatocytes at the carcinogenic dose, demonstrating the hepatotoxicity of MC. CIs were also detected as large micronuclei in liver micronucleus tests but not in the bone marrow, suggesting that MC could cause chromosomal instability specifically in the livers of rats. Reporter gene mutation assays demonstrated that MC did not induce mutagenicity even in the liver. Immunofluorescence analyses revealed that CIs exhibited loss of nuclear envelope integrity, increased heterochromatinization, and accumulation of DNA damage. An increase in liver STING protein levels suggested an effect on the cyclic GMP-AMP synthase/stimulator of interferon genes innate immune pathway. Overall, these data demonstrated the possible occurrence of chromothripsis-like chromosomal rearrangements via CIs. Thus, the formation of CIs could be a crucial event in the early stage of MC-induced hepatocarcinogenesis in F344 rats.

Aflatoxin B1 Induces Inflammatory Liver Injury via Gut Microbiota in Mice.

Aflatoxin B1 (AFB1), a potent food-borne hepatocarcinogen, is the most toxic aflatoxin that induces liver injury in humans and animals. Species-specific sensitivities of aflatoxins cannot be fully explained by differences in the metabolism of AFB1 between animal species. The gut microbiota are critical in inflammatory liver injury, but it remains to reveal the role of gut microbiota in AFB1-induced liver injury. Here, mice were gavaged with AFB1 for 28 days. Then, the modulation of gut microbiota, colonic barrier, and liver pyroptosis and inflammation were analyzed. To further verify the direct role of gut microbiota in AFB1-induced liver injury, mice were treated with antibiotic mixtures (ABXs) to deplete the microbiota, and fecal microbiota transplantation (FMT) was conducted. The treatment of AFB1 in mice altered gut microbiota composition, such as increasing the relative abundance of Bacteroides, Parabacteroides, and Lactobacillus, inducing colonic barrier dysfunction and promoting liver pyroptosis. In ABX-treated mice, AFB1 had little effect on the colonic barrier and liver pyroptosis. Notably, after FMT, in which the mice were colonized with gut microbiota from AFB1-treated mice, colonic barrier dysfunction, and liver pyroptosis and inflammation were obliviously identified. We proposed that the gut microbiota directly participated in AFB1-induced liver pyroptosis and inflammation. These results provide new insights into the mechanisms of AFB1 hepatotoxicity and pave a window for new targeted interventions to prevent or reduce AFB1 hepatotoxicity.

Aflatoxin B1 bioremoval by fungal cells immobilised on magnetic nanoparticles

ABSTRACT Aflatoxins are the most potent hepatocarcinogens of all biologically produced toxins found to date. Contaminated food and commodities are one of the most serious problems due to an irreversible damage to health. Taking advantage of biological methods to improve food safety, an aflatoxin B1 (AFB1) bioremoval study was conducted to investigate the potential of arrested fungal cells on magnetic nanoparticles. The favourable results on the degradation of AFB1 indicate a reasonable influence of the carriers on the fungal cells and the degradation process. The efficacy of degradation of AFB1 by free and immobilised fungal cells on four different magnetic nanoparticles (Fe3O4) was investigated. The degradation rate by HPLC analysis exhibited 54.97% for the free cell study, 85.85% for Fe3O4@MTMS@cell, 95.07% for Fe3O4@TEOS@cell, 84.48% for Fe3O4@SiO2-NH2@cell and 96.52% for Fe3O4@BCD@cell for the 3 μg/ml AFB1. The degradation with Fe3O4@ BCD@cell showed remarkable results even for 5 μg/ml AFB1 resulting 93.42%.

Pyrrolizidine alkaloids in food and phytomedicine: Occurrence, exposure, toxicity, mechanisms, and risk assessment - A review

Among naturally occurring plant constituents, the 1,2-unsaturated pyrrolizidine alkaloids (in the following termed ‘PAs’) play a distinct role because of the large number of congeners occurring in nature and the pronounced toxicity of some congeners. Several PAs are hepatotoxic in humans, experimental and farm animals and were shown to be potent hepatocarcinogens in laboratory rodents. Although the general mode of action leading to toxicity has been elucidated, i.e., being mediated by metabolic conversion of the parent molecule into a highly reactive electrophile capable of attacking cellular target molecules, major questions related to the risk assessment of PAs remain unresolved.It was the aim of a workshop held in September 2018 to shed more light on the occurrence, exposure, mode of action, toxicokinetics and –dynamics of PAs to improve the scientific basis for an advanced toxicological risk assessment. The contributions in nine chapters describe the scientific progress using advanced analytical methods, studies in subcellular fractions, cell culture, experimental animals and humans and the use of PBPK modeling and structure-activity relationship considerations aiming at a better understanding of PA toxicity and genotoxicity. Since PAs differ considerably in their toxic potencies and substantial species differences in sensitivity towards PA exposure exist, a special emphasis was placed on these issues.

Critical role of caveolin-1 in aflatoxin B1-induced hepatotoxicity via the regulation of oxidation and autophagy

Aflatoxin B1 (AFB1) is a potent hepatocarcinogen in humans and exposure to AFB1 is known to cause both acute and chronic hepatocellular injury. As the liver is known to be the main target organ of aflatoxin, it is important to identify the key molecules that participate in AFB1-induced hepatotoxicity and to investigate their underlying mechanisms. In this study, the critical role of caveolin-1 in AFB1-induced hepatic cell apoptosis was examined. We found a decrease in cell viability and an increase in oxidation and apoptosis in human hepatocyte L02 cells after AFB1 exposure. In addition, the intracellular expression of caveolin-1 was increased in response to AFB1 treatment. Downregulation of caveolin-1 significantly alleviated AFB1-induced apoptosis and decreased cell viability, whereas overexpression of caveolin-1 reversed these effects. Further functional analysis showed that caveolin-1 participates in AFB1-induced oxidative stress through its interaction with Nrf2, leading to the downregulation of cellular antioxidant enzymes and the promotion of oxidative stress-induced apoptosis. In addition, caveolin-1 was found to regulate AFB1-induced autophagy. This finding was supported by the effect that caveolin-1 deficiency promoted autophagy after AFB1 treatment, leading to the inhibition of apoptosis, whereas overexpression of caveolin-1 inhibited autophagy and accelerated apoptosis. Interestingly, further investigation showed that caveolin-1 participates in AFB1-induced autophagy by regulating the EGFR/PI3K-AKT/mTOR signaling pathway. Taken together, our data reveal that caveolin-1 plays a crucial role in AFB1-induced hepatic cell apoptosis via the regulation of oxidation and autophagy, which provides a potential target for the development of novel treatments to combat AFB1 hepatotoxicity.

06Dietary Exposure Assessment of Aflatoxin From Dried Figs in Turkey

Aflatoxins are fungi’s secondary toxigenic metabolites and known as potent hepatocarcinogen for humans. The purpose of the present study is to assess health risk for Turkish adult population posing by dried fig consumption due to the aflatoxin contamination. In order to make this evaluation total of 23.547 aflatoxin monitoring data of dried figs from the Turkish Ministry of Food, Agriculture and Livestock between the crop years of 2011/2012-2015/2016 in Turkey were used. Intakes were estimated using consumption data and aflatoxin concentrations and expressed using the average Turkish adults’ body weight 72.8 kg . Estimated daily exposure was found 0.005 ng/kg bw/day for aflatoxin B1 , 0.009 for total aflatoxins in a worst case scenario. The calculated margin of exposure MOE was higher than the 10.000. Cancer risk in Turkish adult population observed in the range between 0.00017 to 0.00030 cancers per 100,000 people per year. Calculated MOE and population risk according to estimated daily intake revealed that Turkish adult population are not under the toxicological risk through dried fig consumption.

Secondary Metabolite Dereplication and Phylogenetic Analysis Identify Various Emerging Mycotoxins and Reveal the High Intra-Species Diversity in Aspergillus flavus.

Aspergillus flavus is one of the most important mycotoxigenic species from the genus Aspergillus, due to its ability to synthesize the potent hepatocarcinogen, aflatoxin B1. Moreover, this fungus is capable of producing several other toxic metabolites from the class of indole-tetramates, non-ribosomal peptides, and indole-diterpenoids. Populations of A. flavus are characterized by considerable diversity in terms of morphological, functional and genetic features. Although for many years A. flavus was considered an asexual fungus, researchers have shown evidence that at best these fungi can exhibit a predominantly asexual existence. We now know that A. flavus contains functional genes for mating, uncovering sexuality as potential contributor for its diversification. Based on our results, we reconfirm that A. flavus is a predominant producer of B-type aflatoxins. Moreover, this fungus can decisively produce AFM1 and AFM2. We did not observe any clear relationship between mating-type genes and particular class of metabolites, probably other parameters such as sexual/asexual ratio should be investigated. A dynamic secondary metabolism was found also in strains intended to be used as biocontrol agents. In addition we succeeded to provide mass spectrometry fragmentation spectra for the most important classes of A. flavus metabolites, which will serve as identification cards for future studies. Both, metabolic and phylogenetic analysis proved a high intra-species diversity for A. flavus. These findings contribute to our understanding about the diversity of Aspergillus section Flavi species, raising the necessity for polyphasic approaches (morphological, metabolic, genetic, etc.) when dealing with this type of complex group of species.

Aflatoxins in rice: Worldwide occurrence and public health perspectives.

Aflatoxins are fungal secondary metabolites that contaminate dietary staples worldwide, including maize, rice and groundnuts. Dietary exposure to aflatoxins is a public health concern due to their carcinogenic, acute and chronic effects. Rice is an important staple food consumed widely and consists of a major part of the diets for half of the world population. Human exposure to these mycotoxins is a serious problem especially in developing countries where hot and humid climates favor the fungal growth and where food storage conditions are poor and lack of regulatory limits enforcement. The recent developments of biomarkers have provided opportunities in assessing aflatoxins exposure and related health effects in the high-risk population groups. This review describes the worldwide occurrence of aflatoxins in rice during the period from 1990 to 2015 and biomarkers-based evidence for human exposure to aflatoxins and their adverse health effects. Aflatoxin is a potent hepatocarcinogen and humans may expose to it at any stage of life. Epidemiological studies reported an association between aflatoxin intake and the incidence of hepatocellular carcinoma in some sub-Saharan and Asian countries. Even daily high intake of rice with a low level of contamination is of health concern. Thus, it is necessary to implement effective strategies to prevent contamination and fungal growth in rice. A good agricultural and manufacturing practice should be applied during handling, storage and distribution of rice to ensure that aflatoxins contamination level is lower in the final product. Moreover, a regular survey for aflatoxins occurrence in rice and biomarkers-based studies is recommended to prevent and reduce the adverse health effects in the world population.

Aflatoxin B1 metabolism: Regulation by phase I and II metabolizing enzymes and chemoprotective agents.

Aflatoxin B1 (AFB1) widely contaminates staple food and feed crops and is well-known as the most potent natural hepatocarcinogen in humans and domesticated animals. This review highlights significant advances in our understanding of the pivotal role of phase I and II metabolizing enzymes in the bioactivation and detoxification of AFB1 and its metabolites across species. In humans, cytochrome P450 (CYP) 1A2, CYP3A4, CYP3A5, and CYP3A7 in liver and CYP2A13 in lung are essential for the bioactivation of AFB1 to the extremely toxic exo-AFB1-8,9-epoxide (AFBO), whereas CYP1A1, CYP1A2, CYP2A6, and CYP3A4 are important in the turkey and duck, CYP1A1 and CYP2A6 are important in the chicken and quail, CYP3A11 and CYP3A13 are important in mice, and CYP2A5 are important in the hamster. In contrast, glutathione-S-transferase (GST) M1 and GSTT1 are primary responsible for detoxification of the AFB1 by catalyzing the conjugation of GSH to AFBO in humans, whereas GSTM2 in a nonhuman primate, GSTA3 in mice, GSTA5 in rats, and GSTA1, GSTA2, GSTA3 and GSTA4 in the turkey are important. Additionally, microsomal epoxide hydrolase (mEH) and aflatoxin-aldehyde reductase (AFAR) have also been shown to play key roles in AFB1 detoxification in the human, rat, and pig. Moreover, an overview of the chemoprotective agents, including synthetic compounds and naturally occurring plant compounds, which can be used to reduce aflatoxicosis is provided based on their ability to regulate these key enzymes. Collectively, this review summarizes the pivotal enzymes in the metabolism of AFB1 among humans, experimental and farm animals, as well as the chemoprotective agents that can be used to minimize risk of aflatoxicosis.

Aflatoxin B1 affects apoptosis and expression of death receptor and endoplasmic reticulum molecules in chicken spleen.

Aflatoxin B1 (AFB1) is a natural product of the Aspergillus genus of molds, which grow on several foodstuffs stored in hot moist conditions, and is among the most potent hepatocarcinogens and immunosuppression presently known. The latter was related to the up-regulated apoptosis of immune organs. However, the effect of expression of death receptor and endoplasmic reticulum molecules in AFB1-induced apoptosis of chicken splenocytes was largely unknown. The objective of this study was to investigate this unknown field. One hundred and forty four one-day-old chickens were randomly divided into control group (0 mg/kg AFB1) and AFB1 group (0.6 mg/kg AFB1), respectively and fed with AFB1 for 21 days. Histological observation demonstrated that AFB1 caused slight congestion and lymphocytic depletion in the spleen. TUNEL and flow cytometry assays showed the excessive apoptosis of splenocytes provoked by AFB1. Moreover, quantitative real-time PCR analysis revealed that AFB1 induced the elevated mRNA expression of Fas, FasL, TNF-α, TNF-R1, Caspase-3, Caspase-8, Caspase-10, Grp78 and Grp94 in the spleen. These findings suggested that AFB1 could lead the excessive apoptosis and alter the expression of death receptor and endoplasmic reticulum molecules in chicken spleen.

Abstract 4247: Quantitative measurement of aflatoxin-serum albumin adducts reveals substantial exposure in Guatemala, a country with high rates of liver cancer mortality in men and women

Abstract Low-income countries across the world are increasingly burdened with growing rates of cancer incidence and mortality. Opportunities for prevention in these populations may be realized most readily for cancer sites with known etiologies that are amenable to intervention. Liver cancer is the sixth-most commonly occurring cancer worldwide and is the second-most common contributor to global cancer mortality. Aflatoxin B1 (AFB1) is a known and potent human hepatocarcinogen, with exposure occurring via ingestion of grains - especially maize - contaminated with Aspergillus flavus. Previous work in regions with endemic levels of liver cancer has shown that reducing AFB1 exposure attenuated liver cancer mortality - even in the presence of other known etiological exposures, such as hepatitis B virus. Guatemala experiences high rates of liver cancer - which is uniquely distributed equally between men and women - and consumes maize as a dietary staple, making the assessment of AFB1 exposure a high priority for cancer prevention efforts in this country. Therefore, we measured circulating levels of the AFB1-albumin adduct, an established biomarker of AFB1 exposure, in adults residing in five geographically and ecologically dispersed departments of Guatemala (Guatemala, Suchitepéquez, Sololá, Escuintla, and Quiché). Healthy men and women aged 40 and older were recruited for the study. Pregnant women or individuals with implanted cardiac devices were excluded from participation. Subjects (n=436) gave informed consent and provided demographic information and a venipuncture blood sample during a clinic visit. Serum was separated from whole blood, digested with protease, subjected to solid-phase extraction, and analyzed with isotope dilution ultrahigh-performance liquid chromatography-triple quadrupole mass spectrometry. Serum albumin was measured by ELISA. AFB1-albumin adducts (pg AFB1-lysine adduct/mg albumin) were detectable in 100% of samples, with a mean ± SEM of 21.6 ± 2.5 and range of 0.2 - 814.8. These levels are similar to those observed in regions of China in the 1980s, prior to reductions in AFB1 exposure and liver cancer mortality. Stratification by demographic factors revealed significant differences in aflatoxin levels in urban (9.6 ± 1.3) versus rural (28.8 ± 3.9) subjects (p ≤ 0.001). Accordingly, AFB1-albumin adduct levels were lowest in the urban municipality of Escuintla (5.8 ± 1.1) and highest in rural Suchitepéquez (36.4 ± 4.8). Exposure was significantly different by sex, with men having higher levels compared to women (30.0 ± 5.4 vs. 15.3 ± 1.3, p = 0.01). These data show that AFB1 exposure in Guatemalan adults is similar to levels previously shown to increase liver cancer risk. Larger cohort and prospective studies are warranted to assess the relationship between liver cancer incidence and AFB1 exposure in this population. Citation Format: Joshua W. Smith, Patricia A. Egner, Mariana Lazo, Alvaro Rivera, Fernanda Kroker, Neal D. Freedman, Katherine A. McGlynn, Manuel Ramirez-Zea, Eliseo Guallar, John D. Groopman. Quantitative measurement of aflatoxin-serum albumin adducts reveals substantial exposure in Guatemala, a country with high rates of liver cancer mortality in men and women [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4247. doi:10.1158/1538-7445.AM2017-4247

Covering the Cover

Covering the Cover

Curcumin Attenuates N-Nitrosodiethylamine-Induced Liver Injury in Mice by Utilizing the Method of Metabonomics.

N-Nitrosodiethylamine (DEN) exists as a food additive in cheddar cheese, processed meats, beer, water, and so forth. It is a potent hepatocarcinogen in animals and humans. Curcumin as a natural dietary compound decreased DEN-induced hepatocarcinogenesis in this research. According to the histopathological examination of liver tissues and biomarker detection in serum and livers, it was demonstrated that curcumin attenuated DEN-induced hepatocarcinogenesis through parts of regulating the oxidant stress enzymes (T-SOD and CAT), liver function (ALT and AST) and LDHA, AFP level, and COX-2/PGE2 pathway. Furthermore, curcumin attenuated metabolic disorders via increasing concentration of glucose and fructose, and decreasing levels of glycine and proline, and mRNA expression of GLUT1, PKM and FASN. Docking study indicated that curcumin presented strong affinity with key metabolism enzymes such as GLUT1, PKM, FASN and LDHA. There were a number of amino acid residues involved in curcumin-targeting enzymes of hydrogen bonds and hydrophobic interactions. All in all, curcumin exhibited a potent liver protective agent inhibiting chemically induced liver injury through suppressing liver cellular metabolism in the prospective application.

Characterization of rat or human hepatocytes cultured in microphysiological systems (MPS) to identify hepatotoxicity

The liver is the main site for drug and xenobiotics metabolism, including inactivation or bioactivation. In order to improve the predictability of drug safety and efficacy in clinical development, and to facilitate the evaluation of the potential human health effects from exposure to environmental contaminants, there is a critical need to accurately model human organ systems such as the liver in vitro. We are developing a microphysiological system (MPS) based on a new commercial microfluidic platform (Nortis, Inc.) that can utilize primary liver cells from multiple species (e.g., rat and human). Compared to conventional monolayer cell culture, which typically survives for 5–7days or less, primary rat or human hepatocytes in an MPS exhibited higher viability and improved hepatic functions, such as albumin production, expression of hepatocyte marker HNF4α and canaliculi structure, for up to 14days. Additionally, induction of Cytochrome P450 (CYP) 1A and 3A4 in cryopreserved human hepatocytes was observed in the MPS. The acute cytotoxicity of the potent hepatotoxic and hepatocarcinogen, aflatoxin B1, was evaluated in human hepatocytes cultured in an MPS, demonstrating the utility of this model for acute hepatotoxicity assessment. These results indicate that MPS-cultured hepatocytes provide a promising approach for evaluating chemical toxicity in vitro.

DNA-Bioprotective Effects of Lactic Acid Bacteria against Aflatoxin B1

Lactic acid bacteria commonly named as probiotics have a broad range of utilization area in human diet and food industry. Besides these known properties of probiotics, in recent years many researchers have focused on their anti-genotoxic called DNA-bioprotective effects. Human gets exposure with genotoxins such as mycotoxins, polycyclic aromatic hydrocarbons, and n-nitroso-compounds through diet and environmental contaminations. Aflatoxin B1 is mycotoxin which was reported one of the most potent hepato-carcinogen and its exposure stems from human diet. In this study, we aimed to investigate DNA-bioprotective effect of Lactobacillus plantarum on human colon adenocarcinoma (Caco-2) cells against Aflatoxin B1 (AFB1) with comet assay without metabolic activation. The results showed that DNA-bioprotective effect of L. plantarum did reduce the AFB1’s genotoxic effect on colon adenocarcinoma (Caco-2) cells. Positive control (50 μM H2O2 applied) and high dose (>10ppm) AFB1 applied cells have the same comet tail appearance. Only visual scoring is performed. Besides negative control cells (Only PBS) and Lactobacillus plantarum+AFB1 mixture showed the same manner with each other; no comet tail detected. These results clearly indicate that L. plantarum is capable of reduce AFB1 safely without producing any by-products.

Correlation of susceptibility to ortho-aminoazotoluene-induced hepatocarcinogenesis with Car and Ahr signaling pathway activation in mice

ortho-Aminoazotoluene (o-AT) is a potent hepatocarcinogen for most mouse strains. Previously, it has been shown that oAT administration activates the aryl hydrocarbon receptor (Ahr) and the constitutive androstane receptor (Car) in the mouse liver. Both receptors are directly involved in hepatocarcinogenesis. In this study, we investigated the effect of chronic o-AT administration on the mRNA expression levels of Ahr, Car, and their target genes Cyp1a1 and Cyp2b10, as well as the correlation of their expression with the degree of inflammatory response in the mouse strains DD/He (DD) and CC57BR/Mv (BR), which are contrasting in their sensitivity to hepatocarcinogenesis. Male mice of both strains received the o-AT oil solution at a dose of 225 mg/kg body weight four times within two months. Control animals received the equivalent solvent amount. The mice were sacrificed after 1 and 4 days since the last o-AT administration. The gene expression levels in the liver were determined by real-time PCR. The inflammatory response was evaluated by the serum concentration of the tumor necrosis factor alpha (TNFα). In resistant BR mice, the o-AT administration induced a more pronounced and prolonged increase in the Cyp1a1 mRNA, indicating the preferential Ahr activation in these animals. At the same time a more pronounced increase in the Cyp2b10 expression level in the sensitive DD mice was observed, suggesting the Car activation. In addition, a strong and prolonged inflammatory response to o-AT administration was noted in the DD mice, but not in BR. It is assumed that the prevalence of the Ahr signaling pathway activation over the Car signaling pathway activation is a factor of the resistance to o-AT-induced hepatocarcinogenesis.

Protective role of garlic oil against oxidative damage induced by furan exposure from weaning through adulthood in adult rat testis

Furan is produced in a wide variety of heat-treated foods via thermal degradation. Furan contamination is found to be relatively high in processed baby foods, cereal products, fruits juices, and canned vegetables. Several studies have demonstrated that furan is a potent hepatotoxin and hepatocarcinogen in rodents. However, few studies have investigated the toxic effects of furan in the testis. In addition, the exact mechanism(s) by which furan exerts toxicity in the testis has not been fully elucidated. In this study, we investigated the potential of furan exposure from weaning through adulthood to induce oxidative stress in adult rat testis, as well as the potential of garlic oil (GO) to ameliorate the induced toxicity. Our results reveal that furan administration significantly reduced serum testosterone levels and increased the levels of malondialdehyde (MDA); furthermore, furan administration decreased significantly the enzymatic activity of testicular antioxidants, including glutathione (GSH), superoxide dismutase (SOD), and catalase (CAT) and induced histopathological alterations in the testis. GO co-administration ameliorated the reduction in testosterone levels and dramatically attenuated the furan-induced oxidative and histopathological changes. In addition, Go significantly down-regulated the increased caspase-3 and cytochrome P450 2E1 (CYP2E1) expression in the furan-treated testis. To the best of our knowledge, this study is the first to demonstrate the furan-induced oxidative changes in the adult rat testis and the protective role of GO to ameliorate these changes through its antioxidant effects and its ability to inhibit CYP2E1 production.

Lime (Citrus aurantifolia L.) Juice a Potent Treatment for the Virulent Hepatocarcinogen Aflatoxin B1 in Peanut Paste

The Aflatoxins are fungal toxins and products of Aspergillus flavus and A. niger. They include B aflatoxins (B1, the most potent hepatocarcinogen known, and B2) which are produced by both species and aflatoxins G (G1 and G2) that are produced by A. niger and aflatoxin M1 and Q1 metabolites of B1 and aflatoxin M2 metabolite of Aflatoxin B2. Since the discovery of aflatoxins in 1960, after an outbreak of a disease of unknown etiology of turkey in England, the scientific approach towards these toxins concentrated on the protective measures and control of the incidence of these carcinogens either. Objective: This study aimed at coming out with a remedy and curing for elimination of aflatoxin B1 in peanut paste. The importance of this stemmed from the fact that aflatoxin occurrence is rather inevitable considering all the advancements in the protective measures. Methods: However, since the incidence of these toxins is rather unavoidable countable attempts were done on the treatment of these toxins in food and feed stuffs. Accordingly this fact persuaded testing some easy and familiar culinary approaches to mitigate and/ or perhaps diminish the presence of aflatoxin B1 (AFLB1) in the commonly consumed peanut (Arachis hypogaea L.) paste. Lime juice, in two doses (12.5 and 25 ml/ g), was applied to 25 g peanut paste contained AFLB1 (7.53 ppb) and stored for 1, 3 and 7 days. The test material was then analyzed for AFLB1 using aflatest® HPLC column of Vicam® of Waters corporation and HPLC Shimatzu® brand. Results: The collected data of the test samples reflected a reduction in AFLB1, due to the doses of 12.5 and 25 ml lime juice, of 11% and 31%, respectively (for one day storage), 54% and 66%, respectively (for 3 days storage), and 74% and 92% (for 7 days storage). Conclusions: These results are encouraging for use of lime juice as a treatment for aflatoxin B1 wherever applicable.

Combination of Loperamide and Niacin modify DENA induced altered Liver enzymes

Hepatocellular Carcinoma (HCC) is among the most lethal cancers which makes it the third most frequent cause of cancer related deaths. Diethylnitrosamine (DENA) is a potent initiator and hepatocarcinogen in rats. DENA induced Hepatocellular damage clearly demonstrates by the elevated levels of liver enzymes serum glutamate oxaloacetate transaminase (SGOT), serum glutamate pyruvate transaminase (SGPT), serum alkaline phosphatase (ALP), and a-feto protein (AFP). This work is an attempt to test the hypothesis that Loperamide (5mg/kg) and Niacin in combination restores the DENA (160mg/kg) induced altered enzymes after single i.p administration in Wistar rats. The ability to alter the enzymes was measured by comparing biochemical serum markers and AFP. The results have confirmed the significant elevation of these parameters in DENA control group compared to normal control and the therapeutic groups. Therapeutic group significantly reveals that Loperamide and Niacin restores the altered hepatic enzymes towards the Normal. Key messages: Our data reveals and confirms that this remarkable combination possess the potential for the treatment of hepatocellular carcinomas in rats exposed to DENA. Administration of Loperamide + Niacin relatively improved the biochemical parameters to values approximating those of the normal controls.

Correlation of susceptibility to ortho-aminoazotolueneinduced hepatocarcinogenesis with Car and Ahr signaling pathway activation in mice

Ortho-aminoazotoluene (OAT) is a potent hepatocarcinogen for most strains of mice. It has previously been shown that OAT application activates the aryl hydrocarbon receptor (Ahr) and the constitutive androstane receptor (Car) in the mouse liver. Both of these receptors are directly involved in the process of hepatocarcinogenesis. In this study, we investigated the effect of chronic OAT administration on the mRNA expression levels of Ahr, Car and their target genes Cyp1a1 and Cyp2b10 in the liver of DD/He (DD) and CC57BR/Mv (BR) mouse strains contrasting in sensitivity to hepatocarcinogenesis. The inflammatory response of these strains was also studied. Male mice of both strains received OAT oil solution at the dose of 225 mg/kg body weight four times within two months. Control animals received the equivalent solvent amount. Mice were sacrificed on days 1 and 4 after the last OAT administration. Gene expression levels in the liver were determined by real-time PCR. The inflammatory response was evaluated by serum concentration of tumor necrosis factor alpha (TNF-alpha). In resistant BR mice, OAT induced a pronounced and prolonged increase in Cyp1a1 mRNA, showing primarily Ahr activation, while the DD strain displayed a more pronounced elevation of Cyp2b10 expression, indicative of Car activation. In addition, a strong inflammatory response to OAT was recorded in DD mice but not in BR. It is assumed that the prevalence of Ahr signaling pathway activation over Car signaling pathway activation is a factor of resistance to OAT-induced hepatocarcinogenesis.