Micronucleus Test of Picrorrhiza Rhizoma Aqueous Extract in Bone Marrow Cells of Male ICR Mice

Low Dose of Nickel and Benzo [a] Anthracene in Rat-Diet, Induce Apoptosis, Fibrosis, and Initiate Carcinogenesis in Liver via NF-Ƙβ Pathway

Environmental contaminants such as polycyclic aromatic hydrocarbon (PAH) and heavy metals are major contaminants of food such as fish thus serving as source of exposure to human. This study was designed to evaluate the carcinogenic risk and other risks associated with long-term consumption of environmentally relevant dose of nickel and benzo [a] anthracene in rats. Thirty-six (36) male rats weighing between 80 and 100 g were assigned into 6 groups of 6 animals each; normal, nickel-, and benzo [a] anthracene-exposed groups for 12 and 24 weeks, respectively. Micronucleus and comet analyses were done in the blood, liver, and bone marrow. Liver function, redox, and inflammatory markers (AST, ALT, GGT, SOD, GSH, MDA, protein carbonyl, protein thiol, total protein, IL-10, 1L-1β, TNF-α, TGF-β NF-Ƙβ, and 8-oxodeoxyguansine) were analysed by standard methods. Immuno-histochemical quantification of Bax, Bcl2, and Erk 1/2 as well as mRNA expression of cyclin D1 was done in liver. From the results, weight gain was observed in varying degrees throughout the exposure period. The polychromatic erythrocytes/normochromatic erythrocytes ratio > 0.2 indicates no cytotoxic effects on the bone marrow. Percentage-MnPCE in blood significantly (p < 0.05) increased throughout exposure duration. Percentage tail DNA in blood was significantly (< 0.05) increased at weeks 20 and 24 in the exposed groups and in liver at weeks 12 (16.22 ± 0.47) and 24 (17.00 ± 0.36) of nickel-exposed rats. The aspartate amino transferase (AST):alanine amino transferase (ALT) ratio indicated fatty liver disease in the benzo [a] anthracene (0.90) and acute liver injury in the nickel (> 10 times greater than the upper limits of the reference group) exposed groups during the first 12 weeks. Observation from the histological and cytological data of the liver revealed the presence of inflammation, fibrosis, and high nuclear/cytoplasmic ratio, respectively, in the nickel and benzo [a] anthracene groups. Only benzo [a] anthracene induced liver oxidative stress with significant (p < 0.05) decrease in SOD (0.64 ± 0.02) activity and increase in protein carbonyl (7.60 ± 0.80 × 10-5) and MDA (57.10 ± 6.64) concentration after 24 weeks. Benzo [a] anthracene up-regulated the cyclin D1 expression and significantly (p < 0.05) increased the levels of the cytokines. Nickel and benzo [a] anthracene significantly (p < 0.05) increased the Bax (183.45 ± 6.50 and 199.76 ± 10.04) and Erk 1/2 (108.25 ± 6.41 and 136.74 ± 4.22) levels when compared with the control (37.43 ± 22.22 and 60.37 ± 17.86), respectively. Overall result showed that the toxic effects of nickel and benzo [a] anthracene might involve fibrosis, cirrhosis, apoptosis, and inflammation of the liver. As clearly demonstrated in this study, benzo [a] anthracene after the 24 weeks of exposure stimulates carcinogenic process by suppressing the liver antioxidant capacity, altering apoptotic, cell proliferation, and differentiation pathways.

Ginger mitigated the health risks associated with arsenic-contamination of rats feed via inflammatory and apoptosis regulation

Millions of people around the world are inadvertently exposed to arsenic through drinking water and food. However, food spices possess antioxidants and anti-inflammatory potentials. Therefore, this study evaluated the protective potentials of Zingiber officinale (ginger) against the toxic effects of arsenic in male Wistar rats. Thirty-six Wistar rats were assigned into 6 groups (n = 6); group A1 and A2 (control), group B1 and B2 were fed with arsenic-contaminated feed (3.45x10-3 mg/kg), group C1 and C2 were feed with arsenic-contaminated feed (3.45x10-3 mg) supplemented with ginger respectively for 12 and 24 weeks. The blood, bone marrow, and liver of rats were harvested and prepared for various analyses. Micronucleus and Comet analysis were performed for the genotoxicity assessment every 4 weeks. Activities of AST, ALT, GGT, and SOD, and the concentration of GSH, MDA, protein carbonyl, protein thiol, and total protein, were measured by spectrophotometric methods. Quantification of IL-10, 1 L-1β, TNF-α, TGF-β NF-Ƙβ, and 8-oxodeoxyguanosine was done by ELISA method while Bax, Bcl2, and Erk 1/2 were quantified by immuno-histochemical staining. mRNA expression of cyclin D1 was quantified using qRT-PCR. Statistical analysis was performed with SPSS and statistical significance was accepted when p<0.05. Result showed significant (p<0.05) decrease in the haemoglobin concentration, red blood cell, lymphocyte counts, tail DNA and MnPCE of rats fed arsenic-contaminated feed compared with control. The supplementation with ginger significantly reduced serum activities of AST and GGT (p<0.05). Ginger supplementation also lowered the arsenic indued increases in liver MDA, protein carbonyl and 8-OXdG levels. Ginger restores to near normal the histological changes due to arsenic exposure. In the arsenic-exposed group, liver IL-10, IL-1β and TNF-α decreased significantly (p<0.05) at week 24 whereas, NF-Ƙβ and TGF-β increased significantly (p 0.05) at weeks 12 and 24 and TNF-α, Bcl2 at week 24. mRNA expression of cyclin D1 was significantly (p<0.05) downregulated in the arsenic and ginger-supplemented groups. This study showed that long-term consumption of arsenic resulted in immunosuppression, anaemia and activated anti-apoptotic process that was mitigated due to ginger supplementation.

Amelioration of Radiation-Induced Damages in Mice by Curcuminoids: The Role of Bioavailability

PURPOSE

The present study investigated the role of free curcuminoids bioavailability on the relative radioprotective efficacy of natural unformulated curcuminoids.

MATERIALS AND METHODS

A food-grade bioavailable formulation of curcuminoids as curcumagalactomannosides (CGM) and unformulated curcuminoids (UC) were employed for the study. Swiss albino mice were randomized into Normal control, Radiation control, Radiation + UC, and Radiation + CGM groups and irradiated with γ-radiation of 6, 8, 10 and 12 Gy. Survival rate, hematological and biochemical parameters, bone marrow cellularity, chromosomal aberrations and histopathology of intestine were followed as a measure of the relative efficacy.Results and Discussion: Oral administration with both UC and CGM at 100 mg/kg. b.wt. produced significant radioprotective effect over the untreated control group of animals. However, CGM treatment was found to provide better clastogenic and genotoxic potential as compared to UC. Further, the histopathology analysis of intestine confirmed the better protective effect of CGM over UC-treated animals.

CONCLUSION

The present study demonstrated the positive role of the bioavailability of curcuminoids in the amelioration of radiation-induced damages in mice since CGM treatment exerted better survival rate and radioprotective effect as compared with UC, despite the relatively low concentrations of curcuminoids in CGM (39% w/w).

Genotoxicity evaluation of a Phragmitis rhizoma extract using a standard battery of in vitro and in vivo assays

ETHNOPHARMACOLOGICAL RELEVANCE

A rhizome of Phragmites communis Trinius has been used in traditional medicine to remove a heat, relieve vomiting and fever, nourish body fluids, and treat diseases like cancers. However, the safety of Phragmitis rhizoma has not yet been fully assessed.

AIM OF THE STUDY

The present study evaluated the genotoxicity of an aqueous extract of Phragmitis rhizoma (AEPR).

MATERIALS AND METHODS

The genotoxic potential of AEPR was evaluated using both in vitro and in vivo assay systems: a bacterial reverse mutation (AMES) test using auxotrophic mutant strains of Salmonella typhimurium (TA100, TA1535, TA98, TA1537) and Escherichia coli (WP2 uvrA), a chromosomal aberration test using Chinese hamster lung cells, and a micronucleus test using bone marrow cells from male ICR mice subjected to an oral administration of AEPR. All tests were completed in compliance with the OECD guidelines or regional regulatory standards for toxicity study, and Good Laboratory Practice.

RESULTS

When compared with the negative control, no genotoxic signs related to the AEPR treatment were observed in the AMES test up to 5000 μg/plate of AEPR and in the chromosomal aberration test up to 500 μg/ml of AEPR regardless of metabolic activation. Repeated oral administration of AEPR up to 5000 mg/kg/day for 2 days did not affect the body weight gains or mortalities of the experimental mice and did not induce any significant changes in the frequency of micronucleated polychromatic erythrocytes.

CONCLUSIONS

The present study demonstrated that aqueous extract of Phragmitis rhizoma is safe regarding genotoxicity in an experimental model at least under the conditions tested. Further toxicity assessment in a human clinical study should be done to support the safe use of Phragmitis rhizoma by patients and healthcare providers.

The research of genetic toxicity of β-phellandrene

β-Phellandrene, a plant extract, can be used as natural pesticides and synthetic materials. As a factor that human may be exposed to, the toxicity information about β-phellandrene is scared at present. This study focused on the genetic toxicity of β-phellandrene. The genetic toxicity of β-phellandrene was evaluated by micronucleus test, comet assay, Ames test, and chromosomal aberration test. In this study, 2850, 1425, 712.5mg/kg β-phellandrene were used in vivo experiments (comet assay and micronucleus test). For Ames test, pure β-phellandrene and different concentrations were used in the experiment. According to the results of cell viability assay (MTT test), the concentration of chromosomal aberration test was formulated. The result of comet assay showed that β-phellandrene can significantly induce DNA damage at the dosage of 1425 and 2850mg/kg. While the results of Micronucleus test and chromosome aberration test showed that β-phellandrene does not lead to apparently genetic toxicity on chromosome level. Ames tests suggest that β-phellandrene had the ability to increase gene mutation with or without S9 mixture. So, it could be drawn that β-phellandrene would have certain genetic toxicity, and the toxicity is reflected as DNA strand breaks and mutation. This study filled the lack of genetic toxicity study of β-phellandrene, and enriched information for risk assessment for β-phellandrene.

Genotoxicity testing of Persicariae Rhizoma (Persicaria tinctoria H. Gross) aqueous extracts

Persicariae Rhizoma (PR) has been used as an anti-inflammatory and detoxification agent in Korea, and contains the biologically active dyes purple indirubin and blue indigo. Despite synthetic indigo showing genotoxic potential, thorough studies have not been carried out on the genotoxicity of PR. The potential genotoxicity of an aqueous extract of PR containing indigo (0.043%) and indirubin (0.009%) was evaluated using a standard battery of tests for safety assessment. The PR extract did not induce any genotoxic effects under the conditions of this study. The results of a reverse mutation assay in four Salmonella typhimurium strains and one Escherichia coli strain indicated that PR extract did not increase the frequency of revertant colonies in any strain, regardless of whether S9 mix was present or not. The PR extract also did not increase chromosomal aberrations in the presence or absence of S9 mix. Although slight signs of diarrhea were restrictedly detected in the mice treated with 2,000 mg/kg PR extract, no noteworthy changes in the frequency of micronucleated polychromatic erythrocytes were observed at doses ≤2,000 mg/kg in a bone marrow micronucleus test. These results indicate the potential safety of the PR extract, particularly if it is consumed in small amounts compared with the quantities used in the genotoxicity tests.