In vitro and in vivo evaluation of the genotoxicity of Eriobotrya japonica leaf extract

Study on Cytotoxic and Genotoxic Potential of Bulgarian Rosa damascena Mill. and Rosa alba L. Hydrosols—In Vivo and In Vitro

The Rosa alba L. and Rosa damascena Mill. growing in Bulgaria are known for their extremely fine essential oil and valuable hydrosols. Irrespectively of its wide use in human life, little research exists on the cytotoxic and genotoxic activity of the hydrosols. This set our goal to conduct cytogenetic analyses to study these effects. A complex of classical cytogenetic methods was applied in three types of experimental test systems—higher plant in vivo, ICR mice in vivo, and human lymphocytes in vitro. Mitotic index, PCE/(PCE + NCE) ratio, and nuclear division index were used as endpoints for cytotoxicity and for genotoxicity—induction of chromosome aberrations and micronuclei. Rose hydrosol treatments range in concentrations from 6% to 20%. It was obtained that both hydrosols did not show considerable cytotoxic and genotoxic effects. These effects depend on the type of the tested rose hydrosols, the concentrations applied in the experiments, and the sensitivity and specificity of the test systems used. Human lymphocytes in vitro were the most sensitive to hydrosols, followed by higher plant and animal cells. Chromosomal aberrations and micronucleus assays suggested that R. damascena and R. alba hydrosols at applied concentrations possess low genotoxic risk. Due to the overall low values in terms of cytotoxic and/or genotoxic effects in all test systems, hydrosols are promising for further use in various areas of human life.

Genotoxicity evaluation of self-assembled-micelle inhibitory RNA-targeting amphiregulin (SAMiRNA-AREG), a novel siRNA nanoparticle for the treatment of fibrotic disease

The self-assembled-micelle inhibitory RNA-targeting amphiregulin (SAMiRNA-AREG) is a novel small-interfering RNA (siRNA) nanoparticle that is used for treatment of pulmonary fibrosis. We investigated the potential genotoxicity of SAMiRNA-AREG based on the guidelines published by the Organization for Economic Cooperation and Development. In the bacterial reverse mutation assay (Ames test), SAMiRNA-AREG did not induce mutations in Salmonella typhimurium TA100, TA1535, TA98, and TA1537 and Escherichia coli WP2uvrA at concentrations of up to 3000 μg/plate with or without metabolic activation. The SAMiRNA-AREG (concentrations up to 500 μg/mL) did not induce chromosomal aberrations in cultured Chinese hamster lung cells with or without metabolic activation. In the in vivo mouse bone marrow micronucleus assay, the SAMiRNA-AREG (concentrations up to 300 mg/kg body weight) did not affect the proportions of polychromatic erythrocytes and total erythrocytes, nor did it increase the number of micronucleated polychromatic erythrocytes in ICR mice. Collectively, these results suggest that SAMiRNA-AREG is safe with regard to genotoxicity such as mutagenesis or clastogenesis under the present experimental conditions. These results might support the safety of SAMiRNA-AREG as a potential therapeutic agent for pharmaceutical development.

Toxicological safety evaluation of the cultivated Chinese cordyceps

ETHNOPHARMACOLOGICAL RELEVANCE

The Chinese cordyceps, a parasitic Thitarodes insect-Ophiocordyceps sinensis fungus complex in the Qinghai-Tibet Plateau, is one of the most valuable traditional Chinese medicines and health food for ameliorating conditions associated with aging and for treating fatigue, night sweats, hyperglycemia, hyperlipidemia, respiratory, renal and liver diseases, and hyposexuality. The natural Chinese cordyceps resource is rare due to its harsh growing environment, limited geographical distribution and global climate warming. Artificial cultivation of Chinese cordyceps has been successfully established to meet its high demand in market.

AIMS OF THE STUDY

The present study aims to evaluate the toxicological safety of the cultivated Chinese cordyceps and provide scientific data for subsequent development and utilization of this valuable biological resource.

MATERIALS AND METHODS

The Chinese cordyceps was cultivated by mimicking the habitat environment in low-altitude areas and identified by morphological and microscopic characteristics. Its phytochemical profile was determined by the HPLC. Toxicological studies based on the cultivated Chinese cordyceps were conducted, including chromosomal aberration test of Chinese hamster lung (CHL) cells, Ames test, acute toxicity test and micronucleus (MN) test of bone marrow cells.

RESULTS

The Chinese cordyceps successfully cultivated in low-altitude areas exhibited the same morphological and microscopic characteristics as natural Chinese cordyceps. The adenosine content was in accordance with the Chinese Pharmacopoeia (2015 Edition). The HPLC fingerprint was determined and five main chromatographic peaks representing uracil, uridine, inosine, guanosine and adenosine were identified. No dose-dependent increase in the rates of chromosomal aberration was detected in the presence or absence of metabolic activation system. Ames test also demonstrated no dose-dependent increase in the number of reversion mutation for five bacterial strains, with or without rat liver microsomal enzyme mixture (S9) metabolic activation, at a quantity range of 128-5000 μg cultivated Chinese cordyceps per plate. The acute toxicity test with mice showed that after 20 g/kg oral administration of cultivated Chinese cordyceps, neither animal death nor any abnormal change in general dissection of various tissues and organs of the animals were found within 14 days. The median lethal dose (LD₅₀) was greater than 5 g/kg, which is regarded as a non-toxic level, and maximum tolerable dose (MTD) of cultivated Chinese cordyceps in ICR mice was more than 20 g/kg. MN test of mouse bone marrow cells indicated no significant differences among each sample dose and the negative control.

CONCLUSION

Based on the results from four toxicological tests, it was concluded that the cultivated Chinese cordyceps was classified as non-toxic in one single administration at high doses by intragastric route in mice. This study provides scientific experimental basis for its safety.

HPLC-ESI-QqQ based standardization, mutagenic and genotoxic potential of methanol extract of Ziziphus mauritiana Lam leaves

BACKGROUND

The leaves of Ziziphus mauritiana Lam have been an integral part of the traditional system of medicine for the treatment of inflammation, wounds, fever, asthma and liver disorders. The leaves are utilised as an edible vegetable in rural parts of India and Indonesia. Despite its pharmacological significance, Ziziphus mauritiana Lam lacks scientific evidence on its mutagenic and genotoxic potential.

RATIONALE

The aim of the present work is to identify bioactive compounds present in the methanol extract of Ziziphus mauritiana Lam leaves (MEZ) using HPLC-ESI-QqQ and to evaluate its mutagenic and genotoxic potential.

METHODS

The phytochemical standardization of the MEZ was done using HPLC-ESI-QqQ. The mutagenic and genotoxic potential of MEZ was tested using bacterial reverse mutation (Ames test), chromosomal aberration, and micronucleus tests. The Ames test was performed in Salmonella typhimurium strains TA98, TA100, TA102, TA1535 and TA1537, and the genotoxic potential was tested in in-vitro using chromosome aberration assay with Chinese hamster ovary (CHO) cells and in-vivo micronucleus test using mouse bone marrow cells.

RESULTS

Fifteen phytochemical compounds were identified in HPLC-ESI- QqQ. It was observed from the Ames test that MEZ did not induce gene mutations in the S. typhimurium in the presence or absence of S9 activation. Similarly, no significant increase in the number of structural aberrations was observed in CHO cells with or without S9 activation. The oral administration of MEZ at a dose of up to 2000 mg/kg caused no significant increase in the number of micronucleated polychromatic erythrocytes or in the mean ratio of polychromatic to total erythrocytes.

CONCLUSION

The findings of the present study confirm that MEZ is not-mutagenic and non-genotoxic in the presence or absence of the exogenous metabolizing system.