In Vitro and In Vivo Genotoxicity Assessment of Aristolochia manshuriensis Kom

Cytotoxic and genotoxic properties of silver nanoparticles synthesized by ethanolic extract of Salacia chinensis

In this study, in vitro and in vivo methods were used to evaluate the cytotoxicity and genotoxicity properties of silver nanoparticles (Ag-NPs) made from a crude ethanolic extract of Salacia chinensis. The test Ag-NPs had no cytotoxicity on the fibroblast cell line at a concentration of 100 μg/mL, according to the MTT assay results. The Chinese hamster ovary (CHO) cell line treated with varied concentrations of test Ag-NPs, with a maximum concentration of 200 μg/mL, did not exhibit any appreciable genotoxic activity, either by comparing the results with positive controls of genotoxicity caused by Methyl methane sulfonate and Benzo (a) pyrene at the concentration of 20 μg/mL, the lack of genotoxicity was established. An in vivo study in Swiss albino mice using various concentrations (250, 500, and 1000 mg/kg) of test Ag-NPs, which were compared with positive controls, further confirmed this in vitro result pattern. Contrary to the genotoxicity caused by the positive control, mouse bone marrow micronucleus testing findings revealed the absence of genotoxicity. These findings imply that at the measured doses, the Ag-NPs produced from the crude ethanolic extract of Salacia chinensis do not exhibit any cytotoxicity or genotoxicity.

The safety of Chinese medicine: A systematic review of endogenous substances and exogenous residues

BACKGROUND

Safety and toxicity have become major challenges in the internationalization of Chinese medicine. Inspite of its wide application, security problems of Chinese medicine still occur from time to time, raising widespread concerns about its safety. Most of the studies either only partially discussed the intrinsic toxicities or extrinsic harmful residues in Chinese medicine, or briefly described detoxification and attenuation methods. It is necessary to systematically discuss Chinese medicine's extrinsic and intrinsic toxic components and corresponding toxicity detoxification or detection methods as a whole.

PURPOSE

This review comprehensively summarizes various toxic components in Chinese medicine from intrinsic and extrinsic. Then the corresponding methods for detoxification or detection of toxicity are highlighted. It is expected to provide a reference for safeguards for developing and using Chinese medicine.

METHODS

A literature search was conducted in the databases, including PubMed, Web of Science,Wan-fang database, and the China National Knowledge Infrastructure (CNKI). Keywords used were safety, toxicity, intrinsic toxicities, extrinsic harmful residues, alkaloids, terpene and macrolides, saponins, toxic proteins, toxic crystals, minerals, heavy metals, pesticides, mycotoxins, sulfur dioxide, detoxification, detection, processing (Paozhi), compatibility (Peiwu), Chinese medicine, etc., and combinations of these keywords. All selected articles were from 2006 to 2022, and each was assessed critically for our exclusion criteria. Studies describe the classification of toxic components of Chinese medicine, the toxic effects and mechanisms of Chinese medicine, and the corresponding methods for detoxification or detection of toxicity.

RESULTS

The toxic components of Chinese medicines can be classified as intrinsic toxicities and extrinsic harmful residues. Firstly, we summarized the intrinsic toxicities of Chinese medicine, the adverse effects and toxicity mechanisms caused by these components. Next, we focused on the detoxification or attenuation methods for intrinsic toxicities of Chinese medicine. The other main part discussed the latest progress in analytical strategies for exogenous hazardous substances, including heavy metals, pesticides, and mycotoxins. Beyond reviewing mainstream instrumental methods, we also introduced the emerging biochip, biosensor and immuno-based techniques.

CONCLUSION

In this review, we provide an overall assessment of the recent progress in endogenous toxins and exogenous hazardous substances concerning Chinese medicine, which is expected to render deeper insights into the safety of Chinese medicine.

Current Trends in Toxicity Assessment of Herbal Medicines: A Narrative Review

Even in modern times, the popularity level of medicinal plants and herbal medicines in therapy is still high. The World Health Organization estimates that 80% of the population in developing countries uses these types of remedies. Even though herbal medicine products are usually perceived as low risk, their potential health risks should be carefully assessed. Several factors can cause the toxicity of herbal medicine products: plant components or metabolites with a toxic potential, adulteration, environmental pollutants (heavy metals, pesticides), or contamination of microorganisms (toxigenic fungi). Their correct evaluation is essential for the patient’s safety. The toxicity assessment of herbal medicine combines in vitro and in vivo methods, but in the past decades, several new techniques emerged besides conventional methods. The use of omics has become a valuable research tool for prediction and toxicity evaluation, while DNA sequencing can be used successfully to detect contaminants and adulteration. The use of invertebrate models (Danio renio or Galleria mellonella) became popular due to the ethical issues associated with vertebrate models. The aim of the present article is to provide an overview of the current trends and methods used to investigate the toxic potential of herbal medicinal products and the challenges in this research field.

Contribution to the Preclinical Safety Assessment of Lannea velutina and Sorindeia juglandifolia Leaves

Dried leaves of Lannea velutina A. Rich. and Sorindeia juglandifolia (A. Rich.) Planch. ex Oliv. (family Anacardiaceae) are used in African traditional medicine. Although these medicinal plants have widespread use in the treatment of inflammatory diseases, there is no scientific data concerning their preclinical or clinical safety. This work aimed to investigate the phytochemical properties of the leaves of both species using HPLC-UV/DAD, as well as the in vivo oral repeated-dose toxicity of 70% hydroethanolic leaf extract of S. juglandifolia and the in vitro genotoxicity of 70% hydroethanolic leaf extracts of L. velutina and S. juglandifolia. Clinical signs of toxicity, body weight variations, and changes in food consumption, mortality, and blood biochemical parameters were monitored. Genotoxicity was assessed using the bacterial reverse mutation assay (Ames test) with and without metabolic activation, according to OECD guidelines. The obtained results showed the presence of gallic acid and anacardic acid as the main marker constituents in both species. No significant changes in general body weight or food intake were observed; small significant changes with no critical relevance were observed in the blood biochemistry of animals treated with S. juglandifolia hydroethanolic extract (50, 400, and 1000 mg/kg body weight) compared to those in the control group. No genotoxicity was observed in the bacterial reverse mutation assay with S. juglandifolia and L. velutina extracts (up to 5 mg/plate). The safety data obtained in vivo and lack of genotoxic potential in vitro points to the safe medicinal use of S. juglandifolia and L. velutina extracts.

Mutagenic potential of medicinal plants evaluated by the Ames Salmonella/microsome assay: A systematic review

The Ames test has become one of the most commonly used tests to assess the mutagenic potential of medicinal plants since they have several biological activities and thus have been used in traditional medicine and in the pharmaceutical industry as a source of raw materials. Accordingly, this review aims to report previous use of the Ames test to evaluate the mutagenic potential of medicinal plants. A database was constructed by curating literature identified by a search on the electronic databases Medline (via Pubmed), Science Direct, Scopus, and Web of Science from 1975 to April 2020, using the following terms: "genotoxicity tests" OR "mutagenicity tests" OR "Ames test" AND "medicinal plants." From the research, 239 articles were selected, including studies of 478 species distributed across 111 botanical families, with Fabaceae, Asteraceae and Lamiaceae being the most frequent. It was identified that 388 species were non-mutagenic. Of these, 21% (83/388) showed antimutagenic potential, most notable in the Lamiaceae family. The results also indicate that 18% (90/478) of the species were mutagenic, of which 54% were mutagenic in the presence and absence of S9. Strains TA98 and TA100 showed a sensitivity of 93% in detecting plant extracts with mutagenic potential. However, the reliability of many reviewed studies regarding the botanical extracts may be questioned due to technical issues, such as testing being performed only in the presence or absence of S9, use of maximum doses below 5 mg/plate and lack of information on the cytotoxicity of tested doses. These methodological aspects additionally demonstrated that a discussion about the doses used in research on mixtures, such as the ones assessed with botanical extracts and the most sensitive strains employed to detect the mutagenic potential, should be included in a possible update of the guidelines designed by the regulatory agencies.

Genome-wide transcriptional analysis of Aristolochia manshuriensis induced gastric carcinoma

Context: Aristolochia manshuriensis Kom (Aristolochiaceae) (AMK) is known for toxicity and mutagenicity.Objective: The tumorigenic role of AMK has yet to be understood.Materials and methods: AMK extracts were extracted from root crude drug. SD (Sprague Dawley) rats underwent gavage with AMK (0.92 g/kg) every other day for 10 (AMK-10) or 20 (AMK-20) weeks. Stomach samples were gathered for histopathological evaluation, microarray and mRNA analysis.Results: The gastric weight to body weight ratio (GW/BW) is 1.7 in the AMK-10 cohort, and 1.8 in AMK-20 cohort compared to control (CTL) cohort. Liver function was damaged in AMK-10 and AMK-20 rats compared to CTL rats. There were no significant changes of CRE (creatinine) in AMK-10 and AMK-20 rats. Histopathological analysis revealed that rats developed dysplasia in the forestomach in AMK-10 rats, and became gastric carcinoma in AMK-20 rats. Genes including Mapk13, Nme1, Gsta4, Gstm1, Jun, Mgst2, Ggt6, Gpx2, Gpx8, Calml3, Rasgrp2, Cd44, Gsr, Dgkb, Rras, and Amt were found to be critical in AMK-10 and AMK-20 rats. Pik3cb, Plcb3, Tp53, Hras, Myc, Src, Akt1, Gnai3, and Fgfr3 worked in AMK-10 rats, and PDE2a and PDE3a played a pivotal role in AMK-20 rats.Discussion and conclusions: AMK induced benign or malignant gastric tumours depends on the period of AMK administration. Genes including Mapk13, Nme1, Gsta4, Gstm1, Jun, Mgst2, Ggt6, Gpx2, Gpx8, Calml3, Rasgrp2, Cd44, Gsr, Dgkb, Rras, Amt, Pik3cb, Plcb3, Tp53, Hras, Myc, Src, Akt1, Gnai3, Fgfr3, PDE2a, and PDE3a were found to be critical in aristolochic acid-induced gastric tumour process.

Acute Oral Toxicity and Genotoxicity of Polysaccharide Fraction from Young Barley Leaves (Hordeum vulgare L.)

Polysaccharides isolated from various plants are considered precious bioactive materials owing to their potent biological activities. Previously, we prepared a polysaccharide fraction (BLE0) isolated from young barley leaves (Hordeum vulgare L.), demonstrating its anti-osteoporotic and immunostimulatory activities. However, data regarding BLE0 toxicity is lacking. To establish its safety, in vitro genotoxicity (chromosomal aberration and bacterial reverse mutation assays) and acute oral toxicity assays were conducted. In the in vitro genotoxicity assays, bacterial reverse mutation and chromosomal aberration assays showed that BLE0 possessed no mutagenicity or clastogenicity. Furthermore, the median lethal dose (LD₅₀) of BLE0 was higher than 5000 mg/kg in female and male Sprague-Dawley (SD) rats and no adverse effects were observed in terms of mortality and abnormal changes in clinical signs (body weight and necropsy). Based on these results, BLE0 was found to be safe with regards to genotoxicity under our test conditions, demonstrating no acute oral toxicity up to 5000 mg/kg in SD rats.

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.

Oral administration of Aristolochia manshuriensis Kom in rats induces tumors in multiple organs

ETHNOPHARMACOLOGICAL RELEVANCE

Aristolochia manshuriensis Kom (AMK), belonging to the Aristolochia family, is traditionally used in China to remove heart fire, promote dieresis, restore menstruation, and enhance milk secretion. The active constitutes of AMK are aristolochic acids (AAs, I and II) that are reported to cause serious side effects including nephrotoxicity and carcinogenicity.

AIM OF THE STUDY

The tumorigenic role of AMK is far to be understood. We analyzed the toxicity reactions after long-term exposure of AMK in rats.

MATERIALS AND METHODS

Sprague-Dawley rats underwent gavage with AMK doses of 51 mg/kg (AMK-1), 253 mg/kg (AMK-2), 508 mg/kg (AMK-3), 1029 mg/kg (AMK-4) or AAs of 15 mg/kg (AAs), and then sacrificed at the 6th, 10th, 14th, 18th, 22th, 26th and 30th weeks. Endpoint measurements included clinical observations, body weights, blood biochemistry, haematology and histomorphological observations.

RESULTS

Body weight decreased after AMK or AAs treatment in rats. AMK destroyed renal function, and induced anemia in rats. AMK caused kidney, stomach, bladder and subcutaneous tumors in rats. In addition, primary hepatic carcinoma was not observed in rats.

CONCLUSIONS

AMK had significant toxic effects in rats with regard to decreased body weight, diminished renal function, increased anemia and tumor incidence. Kidney, stomach, bladder and subcutaneous tissue are carcinogenic target organs of AMK or AAs, however liver is no- carcinogenic target organ of AMK or AAs in rats. AMK is carcinogenic in rats, and not be safe for humans.

Pro-inflammatory and toxicological evaluation of Hepacare® in mice

Objectives

Hepacare^® is a widely marketed herbal formulation in Nigeria for treating chronic liver ailments. This study evaluated the safety, as well as pro-inflammatory and genotoxicity effects, of Hepacare^® in mice.

Methods

The effect of the formulation was estimated in a 28-day study where 25 mice were divided into five groups, and Hepacare^® was orally administered at 250, 500, 750 and 2500 mg/kg body weight. The biochemical and haematological parameters were determined, organ weights were estimated and histopathology was also conducted. mRNA expression of the pro-inflammatory cytokines, TNF-α and IL-6 was estimated by RT-PCR in acute toxicity experiments.

Results

The LD₅₀ was calculated at 3807.89 mg/kg body weight in mice. There was a significant increase (p < 0.05) in the ALP activity in the 750 mg/kg treated group, while the 2500 mg/kg group exhibited significant increases in their AST, ALT, ALP, total bilirubin and total protein levels compared with the control group. However, there was a significant dose related increase in monocytes counts in the groups treated with 750 and 2500 mg/kg. There was no significant difference (p > 0.05) in TNF-α and IL-6 mRNA expression in the genotoxicity studies in all of the treatment groups compared with the control. However, several hepatic and nephro-pathological derangements were observed in the groups treated with higher doses of the formulation.

Conclusions

The study established that the herbal formulation may not induce significant pro-inflammatory toxic responses and genotoxic effects, but prolonged intake of higher doses may cause severe biochemical and clinical abnormalities.

The growing use of herbal medicines: issues relating to adverse reactions and challenges in monitoring safety

The use of herbal medicinal products and supplements has increased tremendously over the past three decades with not less than 80% of people worldwide relying on them for some part of primary healthcare. Although therapies involving these agents have shown promising potential with the efficacy of a good number of herbal products clearly established, many of them remain untested and their use are either poorly monitored or not even monitored at all. The consequence of this is an inadequate knowledge of their mode of action, potential adverse reactions, contraindications, and interactions with existing orthodox pharmaceuticals and functional foods to promote both safe and rational use of these agents. Since safety continues to be a major issue with the use of herbal remedies, it becomes imperative, therefore, that relevant regulatory authorities put in place appropriate measures to protect public health by ensuring that all herbal medicines are safe and of suitable quality. This review discusses toxicity-related issues and major safety concerns arising from the use of herbal medicinal products and also highlights some important challenges associated with effective monitoring of their safety.

Predicting the Drug Safety for Traditional Chinese Medicine through a Comparative Analysis of Withdrawn Drugs Using Pharmacological Network

As the major issue to limit the use of drugs, drug safety leads to the attrition or failure in clinical trials of drugs. Therefore, it would be more efficient to minimize therapeutic risks if it could be predicted before large-scale clinical trials. Here, we integrated a network topology analysis with cheminformatics measurements on drug information from the DrugBank database to detect the discrepancies between approved drugs and withdrawn drugs and give drug safety indications. Thus, 47 approved drugs were unfolded with higher similarity measurements to withdrawn ones by the same target and confirmed to be already withdrawn or discontinued in certain countries or regions in subsequent investigations. Accordingly, with the 2D chemical fingerprint similarity calculation as a medium, the method was applied to predict pharmacovigilance for natural products from an in-house traditional Chinese medicine (TCM) database. Among them, Silibinin was highlighted for the high similarity to the withdrawn drug Plicamycin although it was regarded as a promising drug candidate with a lower toxicity in existing reports. In summary, the network approach integrated with cheminformatics could provide drug safety indications effectively, especially for compounds with unknown targets or mechanisms like natural products. It would be helpful for drug safety surveillance in all phases of drug development.