Potential genotoxicity of plant extracts used in Ethiopian traditional medicine

Developmental toxicity and estrogenic activity of antimicrobial phenolic-branched fatty acids using in silico simulations and in vivo and in vitro bioassay

Due to the growing safety and environmental concerns associated with biocides, phenolic-soy branched chain fatty acids (phenolic-soy BCFAs) are synthesized as new bio-based antimicrobial agents. Safety evaluation is essential before the wide adoption of these new antimicrobial products. This study was initiated to evaluate the safety of four phenolic-soy BCFAs (with phenol, thymol, carvacrol, or creosote branches). Methyl-branched iso-oleic acid, phenol, and creosote were included in the study as controls. In silico toxicity simulation tools predicted that the phenolic BCFAs had much higher toxicities to aquatic organisms than free phenolics did, while the opposite was predicted for rats. The developmental toxicity of four phenolic-soy BCFAs was assessed using an in vivo chicken embryonic assay. Results showed that creosote-soy BCFA had much lower mortality rates than creosote at the same dosages. Additionally, creosote-soy BCFA and methyl-branched iso-oleic acid induced minimal estrogenic activity in the concentration range of 10 nM - 1 µM. Carvacrol-soy BCFA treatments significantly increased (p < 0.05) oxidative stress levels with higher thiobarbituric acid reactive substances in the livers of chicken embryos. Altogether, the phenolic-soy BCFAs, especially creosote-soy BCFA, reported in this study are potentially promising and safer bio-based antimicrobial products.

Toxicity Evaluation of a Non-Pain Pharmacopuncture Extract Using a Bacterial Reverse Mutation Test

Objectives

The objective of this study was to assess the genotoxicity of a no-pain pharmacopuncture (NPP) extract developed in 2022 using a bacterial reverse mutation assay, aiming to further substantiate the safety profile of NPP.

Methods

The genotoxicity evaluation involved a bacterial reverse mutation assay to assess the mutagenic potential of NPP extracts with and without metabolic activation. Histidine-requiring Salmonella typhimurium strains (TA98, TA100, TA1535, and TA1537) and tryptophan-requiring Escherichia coli strains (WP2uvrA) were used in the assay.

Results

The NPP extract did not induce a revertant colony count exceeding two times that of the negative control at any dose level in any of the tested strains, both with and without metabolic activation. Additionally, no growth inhibition or precipitation was observed in the presence of NPP.

Conclusion

Based on the findings, it can be concluded that the NPP extract exhibited no mutagenic potential in the in vitro genotoxicity tests conducted.

Toxicity Assessment of a No-Pain Pharmacopuncture Extract Using a Standard Battery of In Vitro Chromosome Aberration Tests

Objectives

Genotoxicity is evaluated through a chromosomal aberration test using cultured mammalian cells to determine the toxicity of no-pain pharmacopuncture (NPP), which has recently been used to treat musculoskeletal pain disorders in Korean medical clinical practice.

Methods

An initial test was performed to determine the dosage range of the NPP, followed by the main test. In this study, NPP doses of 10.0, 5.0, and 2.5%, and negative and positive controls were tested. An in vitro chromosome aberration test was performed using Chinese hamster lung cells under short-term treatment with or without metabolic activation and under continuous treatment without metabolic activation.

Results

Compared with the saline negative control group, NPP did not significantly increase the frequency of chromosomal abnormalities in Chinese hamster lung cells, regardless of the presence or absence of metabolic activation. Additionally, the number of cells with structural chromosomal abnormalities was significantly higher in the positive control group than that in the negative control group that received saline.

Conclusion

Based on the above results, the chromosomal abnormality-producing effect of NPP was determined to be negative under these test conditions.

Comet assay and hormesis

The paper provides the first assessment of the occurrence of hormetic dose responses using the Comet assay, a genotoxic assay. Using a priori evaluative criteria based on the Hormetic Database on peer-reviewed comet assay experimental findings, numerous examples of hormetic dose responses were obtained. These responses occurred in a large and diverse range of cell types and for agents from a broad range of chemical classes. Limited attempts were made to estimate the frequency of hormesis within comet assay experimental studies using a priori entry and evaluative criteria, with results suggesting a frequency in the 40% range. These findings are important as they show that a wide range of genotoxic chemicals display evidence that is strongly suggestive of hormetic dose responses. These findings have significant implications for study design issues, including the number of doses selected, dose range and spacing. Likewise, the widespread occurrence of hormetic dose responses in this genotoxic assay has important risk assessment implications.

In Vivo Genotoxicity Evaluation of a No-Pain Pharmacopuncture Extract Using the Micronucleus Test

Objectives

We aimed to evaluate the genotoxicity of a recently developed no-pain pharmacopuncture (NPP) targeting muscle relaxation and analgesia using the micronucleus test.

Methods

To evaluate the potential of NPP extracts to induce micronuclei in rat bone marrow cells, a micronucleus test was performed using male Sprague-Dawley rats. The test substance NPP was administered intramuscularly at concentrations of 0.25, 0.5, and 1 mL/animal. Saline was used as the negative control and cyclophosphamide as the positive control.

Results

No NPP treatment-related deaths or abnormal changes in general appearance were observed at any dose level during the experimental period. No statistically significant differences in body weight were observed in any of the NPP dose groups compared to the saline negative control group. NPP did not cause a significant increase in the incidence of micronucleated polychromatic erythrocytes (PCEs) and PCEs or in the ratio of PCE-to-total erythrocytes.

Conclusion

The NPP extract did not exhibit genotoxic in Sprague-Dawley rat bone marrow cells under the conditions of this study. Further toxicity studies of the NPP extract are required.

Evaluation of the antioxidant activity, genotoxic, and cytotoxic effects of the ethanolic leaves extract of Abutilon hirtum (Lam.) Sweet using in vitro assays

Abutilon hirtum (Lam.) Sweet belongs to the Malvaceae family and is a perennial shrub commonly known as Indian mallow, which is distributed in tropical regions and many different areas in Saudi Arabia. A. hirtum is an economically and a medicinally useful plant in different zones of the world for healing various diseases. The current research explores the in vitro antioxidant characteristics and cytotoxic and genotoxic potential effects of the ethanolic leaf extract of A. hirtum (LEAH). Mitotic index (MI), micronucleus (MN), and chromosomal aberration (CA) tests were performed in Allium cepa, and MTT assays were performed using human dermal fibroblast, adult (HDFa) and breast cancer (MCF7) cell lines. The comet assay was used to assess the genotoxic effect of LEAH. The antioxidant activity of LEAH was evaluated by DPPH and superoxide anion free radical scavenging assays. The results revealed that the cytotoxic effects of LEAH on Allium cepa were significantly changed in an inverse relationship with MI (general average for 3 times 0.275) and a direct relationship with MNs and CAs against concentration and treatment time, for highest concentration 1.351 mg/ml were 0.74 and 1.81 respectively. In addition, the MTT test revealed a dose-dependent cytotoxic impact, with the % cell viability decreasing as the concentration of LEAH increased, the lowest % cell viability (19.54) and highest inhibition (80.46) were obtained with 4.40 mg/ml of LEAH. In general, the results indicated that A. hirtum has a damaging effect at high doses; however, a cell safe effect, and a strong antioxidant and DNA protective effect at carefully calculated doses was observed. This provides credibility to justify its general therapeutic activity. Moreover, future studies should identify bioactive molecules and their molecular mechanisms responsible for potential therapies.

Phytochemicals, Antioxidant Activities, and Toxicological Screening of Native Australian Fruits Using Zebrafish Embryonic Model

Phytochemicals play a pivotal role in human health and drug discovery. The safety evaluation of plant extracts is a prerequisite to ensure that all phytochemicals are safe before translational development and human exposure. As phytochemicals are natural, they are generally considered safe, although this is not always true. The objective of this study was to investigate and compare the phytochemical composition, antioxidant potential, and safety evaluation of native Australian Muntries (Kunzea pomifera), Kakadu plum (Terminalia ferdinandiana), Davidson plum (Davidsonia) and Quandong peach (Santalum acuminatum) through the in vivo vertebrate zebrafish embryonic model. The highest total phenolic content (TPC; 793.89 ± 22.27 μg GAE/mg) was quantified in Kakadu plum, while the lowest TPC (614.44 ± 31.80 μg GAE/mg) was quantified in Muntries. Developmental alterations, mortality, and morbidity were assessed for toxicological screening of these selected native Australian fruit extracts. In this study, muntries were quantified as having the least LC50 value (169 mg/L) compared to Davidson plum (376 mg/L), Kakadu plum (>480 mg/L), and Quandong peach (>480 mg/L), which indicates that muntries extract was more toxic than other fruit extracts. Importantly, we found that adverse effects were not correlated to the total phenolic content and antioxidant potential of these native Australian fruits and cannot simply be predicted from the in vitro analysis. Conclusively, these selected native Australian fruit extracts are categorized as safe. This study could explore the use of these native Australian fruits in cosmetics, pharmaceuticals, and drug discovery.

Assessment of antiandrogenic and antispermatogenic activity of Hedera nepalensis in adult male rats

The use of medicinal plants for fertility regulation has been prevalent worldwide for many centuries. They possess natural substances having antiandrogenic properties and can be used as source of contraception. In the current study, methanolic leaf extract of Hedera nepalensis was evaluated for antiandrogenic and antispermatogenic activity in adult male rats through various reproductive parameters. Experimental findings showed significantly increased oxidative stress with reduced antioxidant activity at highest dose regimens in both in vitro and in vivo studies. Increased ROS generation and lipid peroxidation lead to DNA damage in rat sperm. In vivo determination of sperm parameters exhibited notable reduction in sperm motility, viability and DSP in dose-treated animals. Histopathological observations revealed reduced epithelial height and wider lumen having less number of spermatozoa in high-dose-treated groups. Additionally, a marked decline noted in Testosterone concentration in all extract treated groups, while plasma LH and FSH levels only in high-dose-treated groups were noted. The findings of the current study conclude that methanolic leaf extract of H. nepalensis has the potential to disturb male fertility by generating oxidative stress and hormonal imbalance leading to histological alterations and sperm DNA damage.

Nuclear and mitochondrial genome instability induced by fractions of ethanolic extract from Hovenia dulcis Thunberg in Saccharomyces cerevisiae strains

Hovenia dulcis is a plant commonly used as a pharmaceutical supplement, having displayed important pharmacological properties such antigiardic, antineoplastic and hepatoprotective. The purpose of this work was investigate the cytotoxic, genotoxic and mutagenic potential from fractions of Hovenia dulcis ethanolic extract on Saccharomyces cerevisiae strains FF18733 (wild type) and CD138 (ogg1). Ethanolic extract from Hovenia dulcis leaves was fractioned using organic solvents according to increasing polarity: Hexane (1:1), dichlorometane (1:1), ethyl acetate (1:1) and butanol (1:1). Three experimental assays were performed, such as (i) inactivation of cultures; (ii) mutagenesis (canavanine resistance system) and (iii) loss of mitochondrial function (petites colonies). The findings shown a decrease in cell viability in FF18733 and CD138 strains; all fractions of the extract were mutagenic in CD138 strain; only ethyl acetate and butanol fractions increased the rate of petites colonies for CD138 strains. Ethyl acetate and n-butanol fractions induces mutagenicity, at the evaluated concentrations, in mitochondrial and genomic DNA in CD138 strain, mediated by oxidative lesions. In conclusion, it is possible to infer that the lesions caused by the extract fractions could be mediated by reactive oxygen species and might reach multiple molecular targets to cause cellular damage.

Flash-comet: Significantly improved speed and sensitivity of the comet assay through the introduction of lithium-based solutions and a more gentle lysis

Evaluation of primary DNA-damage is one way to identify potential genotoxic agents and for this purpose the Comet assay has, for the last decades, been used to monitor DNA single strand and double strand breaks in individual cells. Various attempts have been made to modify the different steps in the in vitro protocol for the Comet assay in order to improve its sensitivity. However, to the best of our knowledge, nobody has tried to replace the traditionally used NaOH-based electrophoresis solution (pH > 13), with another type of solution. In the present paper, using TK-6 cells exposed to different concentrations of H₂O₂ or ionizing radiation, we present evidence clearly showing that a low-conductive LiOH-based electrophoresis solution at pH 12.5, and a more gentle lysis procedure, significantly improved both the speed and sensitivity of the assay. The new approach, which we call the Flash-comet, is based on a lysis buffer at pH 8.5, an unwinding time of 2.5 min in a LiOH solution without EDTA at pH 12.5, and an electrophoresis time of 1 min at 150 V (5 V/cm) using the same solution.

Phytochemical Study of Aqueous Extract of Ochna schweinfurthiana F. Hoffm Powder Bark and Evaluation of Their Anti-Inflammatory, Cytotoxic, and Genotoxic Properties

Ochna schweinfurthiana has been used in traditional medicine to treat pain, inflammation, and arthritis. It is a rich source of complex dimers of flavonoids with potential use as templates for the development of therapeutic drugs. Hence, the aim of this study was to study the phytochemical content and evaluate the in vitro cytotoxic, genotoxic, and anti-inflammatory activities of the aqueous extract of Ochna schweinfurthiana bark (OSE). Phytochemical study was carried out according to LC-MS procedures, while isolation was carried out using thin layer and column chromatographies. Cytotoxicity was investigated by the mitochondrial viability [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] (MTT) method while genotoxicity potential of the extract was ascertained using the Salmonella typhimurium test strains TA98 and TA100. The anti-inflammatory effect of OSE was evaluated by the in vitro inhibition of 15-lipooxygenase enzyme and bovine serum albumin denaturation (BSA) assays. The investigation of compounds extracted from OSE led to the identification and isolation of six known compounds, namely, hemerocallone (9), 6,7-dimethoxy-3'-4'-dimethoxyisoflavone (10), lithospermoside (13), amentoflavone (14), agathisflavone (15), and β-D-fructofuranosyl-α-D-glucopyranoside (17). In the anti-inflammatory assay, aqueous extracts of the bark showed selective inhibition of 15-lipooxygenase with IC50 value of 32.2 ± 0.36  μg/mL and the result of the bovine serum albumin denaturation assay with IC50 value of 130± 5.78 μg/mL showed moderate activity. The toxicity assay indicated that OSE are noncytotoxic on Vero cell line with LC50 value of 50 mg/mL and nongenotoxic toward Salmonella typhimurium tester strain TA98 and TA100. Result from this study supports the traditional use of the selected medicinal plants in Cameroon for the treatment of inflammatory conditions. Noncytotoxicity and nongenotoxicity of OSE suggest that this plant is safe for use.

Investigation of Safety Profile of Four Copaifera Species and of Kaurenoic Acid by Salmonella/Microsome Test

Trees of the Copaifera genus are native to the tropical regions of Latin America and Western Africa. Copaifera sp is widely used as a popular medicine and it has various ethnopharmacological indications, including gonorrhea, bronchitis, asthma, skin ulcers, ulcers, sore throat, uterine infections, general inflammations, cancer, and leishmanioses. Kaurenoic acid is a naturally occurring diterpene found in Copaifera and has been used as an anti-inflammatory, treatment of ulcer, leishmaniasis, and cancer. Bearing in mind the fact that the Ames test is an excellent tool to assess the safety of extracts, oils, and phytochemicals isolated from medicinal plants, from it, we evaluate the mutagenic potential of four species, between oleoresins (C. oblongifolia; C. langsdorffii) and leaves extracts (C. lucens; C. multijuga), of the Copaifera genus and also of kaurenoic acid, which is one of its major compounds. The results showed that the Copaifera spp. and kaurenoic acid did not induce an increase in the number of revertant colonies, without mutagenic effect in experiments, in the all concentrations evaluated by Ames test. The results obtained in our study support the safe use of the Copaifera genus medicinal plants selected and of kaurenoic acid.

Safety Profile Investigations of Meyna spinosa (Roxb.) and Oroxylum indicum (Linn.) Extracts Collected from Northeast India

Background

Meyna spinosa (M.S) (Roxb.) ex Link and Oroxylum indicum (O.I) (Linn.) Vent, widely used traditional Northeast Indian medicinal plant used for various purposes, have not yet explored for safety profile.

Objective

To investigate the safety profile of M.S (Roxb.) ex Link leaves and O.I (Linn.) Vent stem bark extracts collected from Northeast region of India.

Materials and Methods

In this study, mutagenic, cytotoxic, and genotoxic and/or nontoxic potential of these two plant extracts using various toxicological investigations, as per the regulatory test guidelines, were evaluated. The mutagenic, cytotoxic, and genotoxic potential of these two plants were assayed using Ames test, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, comet assay, and micronucleus test in the bone marrow cells.

Results

The results demonstrated that the tested doses of M.S (Roxb.) ex Link leaves extract showed mutagenic, cytotoxic, and genotoxic effects, whereas O.I (Linn.) Vent stem bark extracts showed nonmutagenic, noncytotoxic, and nongenotoxic effects.

Conclusion

The stem bark extracts of O.I (Linn.) Vent has no mutagenic, cytotoxic, and genotoxic or clastogenic effects in our experimental conditions. However, M.S (Roxb.) ex Link leaves extract caused a significant increase in DNA damage as compared with the positive control, i.e., cyclophosphamide. Thus, the present study revealed that M.S (Roxb.) ex Link leaves extract is toxic, while O.I (Linn.) Vent stem bark extract was found to be safe.

SUMMARY

For the first time, we reported the safety performance of these two plants.The absence of toxicity in Oroxylum indicum (O.I) plant extracts was observed at various doses in animals.Interestingly, our result indicated that Meyna spinosa (M.S) extract shows toxicological effect.Therefore, O.I plant extracts was considered as safer plant extract as compared to M.S. Abbreviations used: MS: Meyna spinosa; OI: Oroxylum indicum.

Genotoxicity study of Ethiopian medicinal plant extracts on HepG2 cells

BACKGROUND

Most of herbal medicines are used without any standard safety and toxicological trials although common assumption is that these products are nontoxic. However, this assumption is incorrect and dangerous, so toxicological studies should be done for herbal drugs. Although Pterolobium stellatum, Otostegia integrifolia and Vernonia amygdalina root extracts are frequently used in Ethiopian traditional medicine, there are no evidences of their active toxic compounds. Therefore, we made an effort to assess probable genotoxic effect of these plant extracts on DNA of human hematoma (HepG₂) cells using alkaline comet assay.

METHODS

Genotoxic effects of extracts were evaluated using single cell gel electrophoresis (SCGE) method on HepG₂ cell. Regarding comet data, the average mean tail intensities (TI) from each individual experiment and treatment (usually at least 3 cultures/treatment) were pooled and the average mean TI was used as an indicator of DNA damage and the standard error of mean (SEM) as the measure of variance.

RESULTS

DNA damage in the form of comet tail has been observed for 1 and 0.5 mg/ml P. stellatum chloroform and 80% methanol extracts on HepG₂ cells, respectively. The chloroform extract of P. stellatum showed increased tail DNA percentage in a concentration dependent manner. Comet tail length in the chloroform P. stellatum extract treated cells (1 mg/ml) was significantly higher by 89% (p < 0.05) compared to vehicle treated controls. The rest of test extracts seemed to be without genotoxic effect up to a concentration of 0.5 mg/ml.

CONCLUSIONS

Our findings show that two extracts from one plant evaluated have a genotoxic potential in vitro which calls for a more thorough safety evaluation. Such evaluation should include other end-points of genotoxicity apart from DNA damage, and possibly also pure compounds.

The genotoxicity of an aqueous extract of Gyejibokryeong-hwan

Background

Gyejibokryeong-hwan (Guizhi Fuling Wan in China), a mixture of five herbal plants, is a well-known treatment for renal diseases including those associated with climacteric syndrome. However, the genotoxicity of Gyejibokryeong-hwan has not yet been well established.

Methods

The present study investigated that the genotoxicity of an aqueous extract of Gyejibokryeong-hwan (GJBRHE): an in vitro chromosomal aberration test using Chinese hamster lung cells, an in vitro bacterial reverse mutation assay (Ames test) with Salmonella typhimurium and Escherichia coli strains, and an in vivo micronucleus test using ICR mouse bone marrow.

Results

GJBRHE with or without the S9 mix showed no genotoxicity in the Ames test up to 5000 μg/plate or in the in vivo MN test up to 2000 mg/kg body weight. In contrast, the chromosomal aberration test showed that GJBRHE induced an increase in the number of chromosomal aberrations compared with the control after treatment for 6 h with 4200 μg/mL GJBRHE in the presence of the S9 mix and for 22 h with 800 μg/mL GJBRHE in the absence of the S9 mix.

Conclusions

GJBRHE did not cause detectable genotoxic effects in the bacterial mutation test or the in vivo MN test, however genotoxic effect was detected in the in vitro chromosomal aberration assay. Our results suggest that GJBRHE may be associated with a low risk of carcinogenesis. Thus, further detailed experiments would be needed to clarify the compound responsible for inducing this genotoxicity of GJBRHE and to determine its mechanism.

Improvised Hand Injury Treatment Using Traditional Veterinary Medicine in Ethiopia

In remote wilderness environments, local people with traditional knowledge of medicinal plants are potentially important first-line health care providers. We present a case of a 31-year-old man who fell off a horse while trekking through a remote mountain landscape in Ethiopia and sustained blunt force trauma to the hand. A local mountain hut keeper examined the patient's hand and used heated leaves of the succulent plant Kalanchoe petitiana to treat a suspected metacarpal fracture. As first responder in a low-resource setting, the hut keeper relied on his traditional knowledge of ethnoveterinary medicine to improvise a treatment for a human injury in a remote mountain environment. Although in this case the outcome of the traditional intervention was positive, our analysis shows that the massage component of the intervention could have led to complications. Conversely, reports from the use of related Kalanchoe species suggest that heated Kalanchoe leaves could be useful in the compression component of traditional care for hand injuries. Validation of traditional remedies and their therapeutic potential are needed if they are to complement wilderness wound care safely and reliably. The documentation and validation of these remedies are urgently needed, as many medicinal plants and indigenous knowledge of how to use these valuable natural resources are being lost.

The Genus Rumex: Review of traditional uses, phytochemistry and pharmacology

ETHNOPHARMACOLOGICAL RELEVANCE

The approximately 200 species of the genus Rumex (sorrel, Polygonaceae) are distributed worldwide (European, Asian, African and American countries). Some species have been used traditionally as vegetables and for their medicinal properties. Based on the traditional knowledge, different phytochemical and pharmacological activities have been at the focus of research. This review aims to provide an overview of the current state of knowledge of local and traditional medical uses, chemical constituents, pharmacological activities, toxicity, and safety of Rumex species, in order to identify the therapeutic potential of Rumex species and further directions of research.

MATERIALS AND METHODS

The selection of relevant data was made through a search using the keyword "Rumex" in "Scopus", "Google Scholar", "Web of Science", "PubMed", and "ScienceDirect" databases. Plant taxonomy was validated by the databases "The Plant List", and "Mansfeld's Encyclopedia". Additional information on traditional use and botany was obtained from published books and MSc dissertations.

RESULTS

This review discusses the current knowledge of the chemistry, the in vitro and in vivo pharmacological studies carried out on the extracts, and the main active constituents, isolated from plants of genus Rumex. Although, there are about 200 species in this genus, most of the phytochemical and pharmacological studies were performed on up to 50 species. The aerial parts, leaves and roots of the plants are used as vegetables and for the treatment of several health disorders such as mild diabetes, constipation, infections, diarrhoea, oedema, jaundice, and as an antihypertensive, diuretic and analgesic and in case of skin, liver and gallbladder disorders, and inflammation. Many phytochemical investigations on this genus confirmed that Rumex species are rich in anthraquinones, naphthalenes, flavonoids, stilbenoids, triterpenes, carotenoids, and phenolic acids. Moreover, it draws the attention that high level of oxalic acid in some species can cause toxicity (kidney stones) if consumed large quantity.

CONCLUSIONS

This review confirms that some Rumex species have emerged as a good source of the traditional medicine for treatment of inflammation, cancer and different bacterial infections and provides new insights for further promising investigations on isolated compounds, especially quercetin 3-O-glucoside, emodin, nepodin, torachrysone, and trans-resveratrol to find novel therapeutics and aid drug discovery. In addition, hepatoprotective, antiviral and antidiabetic activities should have priority in future pharmacological studies. However, for applying species to prevent or treat various diseases, additional pharmacological studies are needed to find the mechanism of actions, safety and efficacy of them before starting clinical trials.

Pharmacological Studies of Artichoke Leaf Extract and Their Health Benefits

Artichoke (Cynara scolymus) leaf extract was one of the few herbal remedies which the clinical and experimental trials have complemented each other. Both experimental and clinical effects have been verified through extensive biomedical herbal remedy research. Specifically, antioxidant, choleretic, hepatoprotective, bile-enhancing and lipid-lowering effects have been demonstrated, which corresponded with its historical use. Ongoing research seems to indicate that artichoke indeed have medicinal qualities. Most significant appears to be its beneficial effect on the liver. In animal studies, liquid extracts of the roots and leaves of artichoke have demonstrated an ability to protect the liver, with possibly even to help liver cells regenerate. Although research is not yet conclusive, scientists were optimistic that its long-standing use in humans for digestive and bowel problems was indeed justified. It may also play a role in lowering cholesterol and thus help to prevent heart disease. Boiled wild artichoke reduced postprandial glycemic and insulinemic responses in normal subjects but has no effect on metabolic syndrome patients. This article intended to review the wide ranging pharmacological effects of artichoke leaf extract.

Genotoxicity evaluation of Oryeong-san water extract using in vitro and in vivo tests

Background

Oryeong-san, a mixture of five herbal plants, is a well-known therapy for renal-associated diseases such as those manifesting edema, dysuria, and oliguria.

Methods

In the present study, we investigatee the potential genotoxic effects of a water extract of Oryeong-san (ORSE) in three mutagenicity assays (an in vitro bacterial reverse mutation assay (Ames test) with Salmonella typhimurium and Escherichia coli strains, an in vitro mammalian chromosomal aberration test using Chinese hamster lung cells, and an in vivo micronucleus test using ICR mice bone marrow).

Results

ORSE showed no genotoxicity in the Ames test up to 5000 μg/plate; the in vitro chromosome aberration test showed no significant structural aberrations with and without the S9 mix up to 5000 μg/mL, or the in vivo micronucleus test up to 2000 mg/kg body weight.

Conclusions

In conclusion, under the current test conditions, ORSE seems safe for use; however, other genotoxicity tests (e.g. sister-chromatid exchange or Comet) or chronic toxicity tests are warranted.

Evaluation of a water extract of So-Cheong-Ryong-Tang for acute toxicity and genotoxicity using in vitro and in vivo tests

Background

So-Cheong-Ryong-Tang, a traditional Korean medicine, has been used empirically for the treatment of asthma, allergic rhinitis, and colds for hundreds of years. However, its genotoxicity has been rarely examined.

Methods

We therefore investigated the genotoxicity of an aqueous extract of So-Cheong-Ryong-Tang (SCRT) in two in vitro and one in vivo assays: a bacterial reverse mutation assay (Ames test), a chromosomal aberration assay, and a micronucleus assay, respectively.

Results

In the bacterial reverse mutation assay, SCRT did not increase revertant colony numbers in Salmonella. typhimurium strains (TA98, TA100, TA1535, and TA1537) or an Escherichia coli strain (WP2 uvrA) regardless of metabolic activation or the duration of treatment. However, statistically significant differences in the incidence of chromosomal aberrations following SCRT >4000 μg/mL were observed in Chinese hamster lung cells exposed with or without an S9 enzyme and cofactor mixture.

Conclusions

These results suggest further genotoxic testing of SCRT, such as a comet assay, to ascertain its generally recognized safety.

Electronic supplementary material

The online version of this article (doi:10.1186/s12906-015-0737-x) contains supplementary material, which is available to authorized users.

Gastroprotective potential against indomethacin and safety assessment of the homology of medicine and food formula cuttlebone complex

Cuttlebone complex (CBC), a homology of medicine and food formula, is comprised of five herbal medicines (Endoconcha Sepiae, Radix Paeoniae Rubra, fresh ginger, Fructus Amomi, and Radix Glycyrrhizae) and two food ingredients (Zingiber zerumbet and chitosan). Herein, the gastroprotective potential against indomethacin and a safety assessment of CBC were investigated. In a gastroprotective model, CBC effectively decreased the indomethacin-increased gastric ulcerous lesions, and increased the indomethacin-decreased prostaglandin E2 levels in the gastric mucosa. In genotoxicity tests, CBC treatment did not increase the numbers of revertant colonies in five Salmonella typhimurium strains and chromosome aberrations in Chinese hamster ovary CHO-K1 cells, with or without S9 metabolic activation. The oral supplementation of CBC did not increase micronucleus formation in the peripheral blood of mice. In a subacute toxicity study, the body weight and blood biochemical parameters observed in CBC-treated rats were normal. In conclusion, CBC was considered as a non-toxic formula and could be used to remedy indomethacin-induced gastric damage.

Investigation of repeated dose (90 day) oral toxicity, reproductive/developmental toxicity and mutagenic potential of 'Calebin A'

The present work investigated repeated dose and reproductive toxicity of Calebin A in Wistar rats. A study for assessing the mutagenic potential of Calebin A through an AMES test is also described. Calebin A was orally administered to groups of 10 male and/or 10 female Wistar rats each, assigned to three dose levels (20, 50 and 100 mg/kg/body weight) once daily for 90 consecutive days. None of the animals in any of the treatment/control groups exhibited any abnormal clinical signs/behavioral changes, reproductive as well as developmental parameters, or gross and microscopic changes in both male and female rats. Calebin A was also evaluated for its ability to induce reverse mutations at selected loci of Salmonella typhimurium in the presence and absence of Aroclor 1254 induced rat liver S9 cell lines. In conclusion, 100 mg/kg/d of Calebin A is not likely to produce any significant toxic effects in male and female Wistar rats and no reproductive or developmental toxicity was observed at the same dose and hence Calebin A at 100 mg/kg was determined as “No Observed Adverse Effect Level (NOAEL)” under the test conditions.

Antigenotoxic and antioxidant effects of the Mongolian medicinal plant Leptopyrum fumarioides (L): an in vitro study

ETHNOPHARMACOLOGICAL RELEVANCE

Leptopyrum fumarioides has been used in the traditional medicine of Mongolia for the treatment of various diseases, including drug intoxications. However, since there is only sparse information about its chemistry, active components, and pharmacological and toxicological effects, the major aim of the present study employing mouse lymphoma cells was to evaluate the genotoxic and antigenotoxic/antioxidative effects of extracts and components isolated from this plant.

MATERIAL AND METHODS

A crude methanol extract was separated into three different sub-extracts: dichloromethane, n-butanol, and water. The major constituent of the n-butanol extract, i.e., the flavone luteolin-7-O-glucoside and a mixture of the most abundant compounds in the dichloromethane sub-extract were then isolated. DNA damage was evaluated using the comet assay; the antioxidant activity was evaluated using the DPPH radical scavenging assay.

RESULTS

The crude methanol extract, the dichloromethane sub-extract and the mixture of compounds isolated from the latter fraction, increased the level of DNA damage after three hours of exposure. In contrast, no increase in DNA damage was observed in the cells that had been exposed to the n-butanol and water sub-extracts, or to the pure flavone. When non-DNA damaging concentrations of extracts and compounds were tested together with the DNA damaging agent catechol, all sub-extracts were found to reduce the catechol-induced DNA damage (the flavone was then found to be the most effective protective agent). The n-butanol sub-extract and the flavone were also found to have the most prominent antioxidative effects.

CONCLUSION

Based on the results from the present study, components in Leptopyrum fumarioides were found to protect the DNA damage induced by catechol, probably by acting as potent antioxidants.

Genotoxicity evaluation of Guibi-Tang extract using an in vitro bacterial reverse mutation assay, chromosome aberration assay, and in vivo micronucleus test

Background

Guibi-Tang is a traditional herbal prescription made from 12 different herbs that is used in the treatment of amnesia and poor memory.

Methods

In the present study, we evaluated the acute oral toxicity and genotoxic potential of Guibi-Tang water extract (GBT) at doses up to 2000 μg/plate an using a bacterial reverse mutation test (Ames test) with Salmonella typhimurium strains TA100, TA1535, TA98, and TA1537, and Escherichia coli strain WP2uvrA. Acute toxicity and genotoxic potential were measured in the presence and absence of an exogenous source of metabolic activation, in an in vitro chromosome aberration assay with Chinese hamster lung (CHL) cells, and in an in vivo micronucleus test using ICR mice bone marrow as recommended by the Korean Food and Drug Administration. An acute oral toxicity test of GBT was performed in Sprague Dawley rats. The Ames test showed that GBT did not induce gene mutations in S. typhimurium or in E. coli in the presence or absence of S9 activation.

Results

GBT did not significantly increase the number of structural aberrations in CHL cells with or without S9 activation. The oral administration of GBT 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.

Conclusions

However, as we did not identify the components of GBT responsible for these effects, other assays are needed to confirm its genotoxicity.

The current status of knowledge of herbal medicine and medicinal plants in Fiche, Ethiopia

BACKGROUND

A majority of Ethiopians rely on traditional medicine as their primary form of health care, yet they are in danger of losing both their knowledge and the plants they have used as medicines for millennia. This study, conducted in the rural town of Fiche in Ethiopia, was undertaken with the support of Southern Cross University (SCU) Australia, Addis Ababa University (AAU) Ethiopia, and the Ethiopian Institute of Biodiversity (EIB), Ethiopia. The aim of this study, which included an ethnobotanical survey, was to explore the maintenance of tradition in the passing on of knowledge, the current level of knowledge about medicinal herbs and whether there is awareness and concern about the potential loss of both herbal knowledge and access to traditional medicinal plants.

METHODS

This study was conducted using an oral history framework with focus groups, unstructured and semi-structured interviews, field-walk/discussion sessions, and a market survey. Fifteen people were selected via purposeful and snowball sampling. Analysis was undertaken using a grounded theory methodology.

RESULTS

Fourteen lay community members and one professional herbalist provided information about 73 medicinal plants used locally. An ethnobotanical survey was performed and voucher specimens of 53 of the plants, representing 33 families, were collected and deposited at the EIB Herbarium. The community members are knowledgeable about recognition of medicinal plants and their usage to treat common ailments, and they continue to use herbs to treat sickness as they have in the past. A willingness to share knowledge was demonstrated by both the professional herbalist and lay informants. Participants are aware of the threat to the continued existence of the plants and the knowledge about their use, and showed willingness to take steps to address the situation.

CONCLUSION

There is urgent need to document the valuable knowledge of medicinal herbs in Ethiopia. Ethnobotanical studies are imperative, and concomitant sustainable programmes that support the sustainability of herbal medicine traditions may be considered as a way to collect and disseminate information thereby supporting communities in their efforts to maintain their heritage. This study contributes to the documentation of the status of current traditional herbal knowledge in Ethiopia.

Anti-inflammatory and mutagenic evaluation of medicinal plants used by Venda people against venereal and related diseases

ETHNOPHARMACOLOGY RELEVANCE

Inflammation is a major risk factor for various human diseases including venereal diseases, often resulting in treatment complications. Plants have been traditionally used for treatment of many different diseases and have been successfully proven to be an alternative source in treatment of infectious diseases.

AIM OF THE STUDY

This study was aimed at evaluating the anti-inflammatory activities and the mutagenic properties of 12 medicinal plants used by the Venda people against venereal and related diseases.

MATERIALS AND METHODS

The plants were evaluated for their anti-inflammatory activity against the cyclooxygenase (COX-1 and -2) enzymes and genotoxicity using the Ames test, with and without S9 (metabolic activation) against Salmonella typhimurium tester strain TA98.

RESULTS

DCM and PE extracts of Adansonia digitata bark, Bolusanthus speciosus bark, Pterocarpus angolensis bark and Pappea capensis leaves and EtOH and water extracts of Bolusanthus speciosus stem and Ekebergia capensis bark showed the best anti-inflammatory activity in both COX-1 and -2 assays at 250 μg/ml. These were further evaluated at three other concentrations (31.25, 62.5, and 125 μg/ml) to determine IC50 values. Water extracts of Ekebergia capensis bark showed the best IC50 value towards COX-1. The Ames test revealed that all plant extracts were non-mutagenic towards Salmonella typhimurium strain TA98 except for Elephantorrhiza burkei and Ekebergia capensis that showed weak mutagenicity.

CONCLUSION

The active plants may offer a new source of chemicals for the effective treatment of anti-inflammatory conditions related to venereal diseases.

An in vitro study on the DNA damaging effects of phytochemicals partially isolated from an extract of Glinus lotoides

An extract of Glinus lotoides, a medicinal plant used in Africa and Asia for various therapeutic purposes, was recently shown to cause DNA damage in vitro. To further explore the potential genotoxicity of this plant, fractionation of the crude extract was performed using reverse phase solid-phase extraction and a stepwise gradient elution of methanol in water. Four fractions were collected and subsequently analysed for their DNA damaging effects in mouse lymphoma cells using an alkaline version of the comet assay. To identify potential genotoxic and non-genotoxic principles, each fraction was then subjected to liquid chromatography coupled to mass spectrometry, LC-MS/MS. 1D and 2D nuclear magnetic resonance analyses were used to confirm the identity of some saponins. Although fractions containing a mixture of flavonoids and oleanane-type saponins or oleanane-type saponins alone produced no DNA damage, those containing hopane-type saponins exhibited a pronounced DNA damaging effect without affecting the viability of the cells. To conclude, even if this study presents evidence that hopane-type of saponins are endowed with a DNA damaging ability, further studies are needed before individual saponins can be cited as a culprit for the previously reported genotoxicity of the crude extract of G. lotoides.

Genetic toxicology evaluation of essential oil of Alpinia zerumbet and its chemoprotective effects against H(2)O(2)-induced DNA damage in cultured human leukocytes

Essential oil (EO) of Alpinia zerumbet leaves, at non-toxic concentrations (50-300 μg/mL), did not induce genotoxicity in human leukocytes. However, at the highest concentration (500 μg/mL) tested caused a reduction in cell proliferation and viability, and an increase in DNA damage. Moreover, in vivo experiments showed that EO (400 mg/kg) did not exert mutagenicity on peripheral blood cells and bone marrow in mice. In DPPH test, EO showed scavenging effects against DPPH radicals, and other free radicals (determination of intracellular GSH and lipid peroxidation assays). Furthermore, EO was able to reduce the intracellular levels of ROS, and prevented leukocytes DNA against oxidative damage. The ability of EO to reduce H(2)O(2) toxicity was observed only when cells were treated with EO during and after exposure to H(2)O(2). With the co- and post-treatment procedures, EO decreased the frequency of apoptotic and micronucleated leukocytes as well DNA strand breaks. However, a synergistic effect was observed in cultures exposed to 500 μg/mL EO. In conclusion, EO at concentrations up to 300 μg/mL or doses up to 400mg/kg are not mutagenic in leukocytes and in mice, but do have antioxidative and protective effects against the cytotoxicity and clastogenesis induced by H(2)O(2).

Plant use in Odo-Bulu and Demaro, Bale region, Ethiopia

This paper reports on the plant use of laypeople of the Oromo in Southern Ethiopia. The Oromo in Bale had names/uses for 294 species in comparison to 230 species documented in the lower reaches of the Bale area. Only 13 species was used for veterinary purposes, or as human medicine (46). Plant medicine served mostly to treat common everyday ailments such as stomach problems and diarrhea, for wound treatment and as toothbrush-sticks, as anthelmintic, for skin infections and to treat sore muscles and. Interestingly, 9 species were used to treat spiritual ailments and to expel demons. In most cases of medicinal applications the leaves or roots were employed.Traditional plant knowledge has clearly declined in a large part of the research area. Western style health care services as provided by governments and NGOs, in particular in rural areas, seem to have contributed to a decline in traditional knowledge, in part because the local population simply regards western medicine as more effective and safer.

Implementation of the three Rs in the human hazard assessment of Brazilian medicinal plants: an evaluation of the cytotoxic and genotoxic potentials of Dipteryx alata Vogel

In Brazil, medicinal plants are widely used by the indigenous people, which leads to a constant requirement for toxicity tests to be performed on the plant extracts. Although the current Brazilian Directive 90/2004 on the preclinical toxicity testing of phytotherapeutics recommends only in vivo tests, some Brazilian researchers would like to change this situation by implementing the Three Rs in the toxicological testing of medicinal plants. The present study evaluated the cytotoxic and genotoxic potentials of bark extracts from Dipteryx alata Vogel, a medicinal plant of the Brazilian cerrado, by using CHO-K1 (Chinese hamster ovary) cells. An IC50 value was obtained, which corresponded to 0.16mg/ml of plant extract, and from this the equivalent LD50 was determined as 705mg/kg. In order to determine the genotoxic potential of the sample, the frequency of micronucleus formation was assessed. CHO-K1 cells were exposed, during targeted mitosis, to different concentrations of plant extract and cytochalasin B, in the presence and absence of an appropriate metabolic activation system (an S9 mix). The results obtained indicated that it might be possible to implement the Three Rs in assessing the potential human hazard of medicinal plants. The publication of such data can increase awareness of the Three Rs by showing how to optimise the management of animal use, if in vivo toxicological experiments are required.

In vitro biocompatibility of chitosan porous skin regenerating templates (PSRTs) using primary human skin keratinocytes

Biopolymer chitosan (beta-1,4-d-glucosamine) comprises the copolymer mixture of N-acetylglucosamine and glucosamine. The natural biocompatibility and biodegradability of chitosan have recently highlighted its potential use for applications in wound management. Chemical and physical modifications of chitosan influence its biocompatibility and biodegradability, but it is unknown as to what degree. Hence, the biocompatibility of the chitosan porous skin regenerating templates (PSRT 82, 87 and 108) was determined using an in vitro toxicology model at the cellular and molecular level on primary normal human epidermal keratinocytes (pNHEK). Cytocompatibility was accessed by using a 3-[4,5-dimethyl-2-thiazolyl]-2,5-diphenyl tetrazolium bromide (MTT) assay from 24 to 72h. To assess the genotoxicity of the PSRTs, DNA damage to the pNHEK was evaluated by using the Comet assay following direct contact with the various PSRTs. Furthermore, the skin pro-inflammatory cytokines TNF-alpha and IL-8 were examined to evaluate the tendency of the PSRTs to provoke inflammatory responses. All PSRTs were found to be cytocompatible, but only PSRT 108 was capable of stimulating cell proliferation. While all of the PSRTs showed some DNA damage, PSRT 108 showed the least DNA damage followed by PSRT 87 and 82. PSRT 87 and 82 induced a higher secretion of TNF-alpha and IL-8 in the pNHEK cultures than did PSRT 108. Hence, based on our experiments, PSRT 108 is the most biocompatible wound dressing of the three tested.

Modulatory role of alizarin from Rubia cordifolia L. against genotoxicity of mutagens

Rubia cordifolia L. (Rubiaceae) is an important medicinal plant used in the Ayurvedic medicinal system. Its use as a traditional therapeutic has been related to the treatment of skin disorders and cancer. Besides its medicinal value, anthraquinones from this plant are used as natural food colourants and as natural hair dyes. Dyes derived from natural sources have emerged as important alternatives to synthetic dyes. Alizarin (1,2-dihydroxyanthraquinone) was isolated and characterized from R. cordifolia L. and evaluated for its antigenotoxic potential against a battery of mutagens viz. 4-nitro-o-phenylenediamine (NPD) and 2-aminofluorene (2-AF) in Ames assay using TA98 tester strain of Salmonella typhimurium; hydrogen peroxide (H(2)O(2)) and 4-nitroquinoline-1-oxide (4NQO) in SOS chromotest using PQ37 strain of Escherichia coli and in Comet assay using human blood lymphocytes. Our results showed that alizarin possessed significant modulatory role against the genotoxicity of mutagens.