In vitro Toxicity and Genotoxic Activity of Aqueous Leaf Extracts From Four Varieties of Olea europea (L)

Mutagenic and antimutagenic evaluation of Asparagus laricinus Burch., Senecio asperulus DC., and Gunnera perpensa L. to hepatic cells

Introduction. The use of traditional medicinal plant concoctions to cure or treat different diseases daily in African folk medicine. However, the effects of most medicinal plants on human health or genetic material remain unknown. This study thus aimed to evaluate the mutagenic and antimutagenic potentials of Asparagus laricinus Burch. cladodes, Senecio asperulus DC., and Gunnera perpensa L. roots extract in vitro. Methods. Neutral red uptake assay, alkaline comet assay, and the VITOTOX test was used with plant extract dilutions of 4, 20, 50, and 100 µg/ml, respectively, on hepatic (C3A) cells and Salmonella Typhimurium TA104 strains. Ethyl methane-sulfonate and 4-nitroquinoline oxide were used as positive controls for the comet and VITOTOX assays, respectively. Results.  In vitro cytotoxicity and genotoxicity were not observed from all tested extracts, except for the two dichloromethane (DCM) extracts of S. asperulus and G. perpensa, which appeared to be cytotoxic with S9 metabolic activation, but not genotoxic or mutagenic. From the VITOTOX test results, none of the extracts appeared to have antimutagenic properties after treating S. Typhimurium strains with a known mutagen. Conclusions. These results confirm that previously reported anticarcinogenic properties of A. laricinus, S. asperulus, and G. perpensa did not result from the protective mechanism against genotoxicity but from other ones. Moreover, the negative mutagenic and cytotoxic activities of the tested plants highlighted the safe use of these medicinal plants in vitro. Therefore, S. asperulus and G. perpensa DCM extracts require further investigation for their possible in vivo cytotoxic effects on humans.

Genotoxic effects of Dukhan: A smoke bath from the wood of Acacia seyal used traditionally by Sudanese women

ETHNOBOTANICAL RELEVANCE

Smoke from the wood of Acacia seyal Delile has been used by Sudanese women for making a smoke bath locally called Dukhan. The ritual is performed to relieve rheumatic pain, smooth skin, heal wounds and achieve general body relaxation.

AIM OF THE STUDY

The present study was designed to investigate the in vitro anti-inflammatory effect of the smoke condensate using cyclooxygenase -1 (COX-1) and -2 (COX-2) as well as its potential genotoxic effects using the bacterial-based Ames test and the mammalian cells-based micronucleus/cytome and comet assays.

MATERIAL AND METHODS

The smoke was prepared in a similar way to that commonly used traditionally by Sudanese women then condensed using a funnel. Cyclooxygenase assay was used to evaluate its in vitro anti-inflammatory activity. The neutral red uptake assay was conducted to determine the range of concentrations in the mammalian cells-based assays. The Ames, cytome and comet assays were used to assess its potential adverse (long-term) effects.

RESULTS

The smoke condensate did not inhibit the cyclooxygenases at the highest concentration tested. All smoke condensate concentrations tested in the Salmonella/microsome assay induced mutation in both TA98 and TA100 in a dose dependent manner. A significant increase in the frequency of micronucleated cells, nucleoplasmic bridges and nuclear buds was observed in the cytome assay as well as in the % DNA damage in the comet assay.

CONCLUSIONS

The findings indicated a dose dependent genotoxic potential of the smoke condensate in the bacterial and human C3A cells and may pose a health risk to women since the smoke bath is frequently practised. The study highlighted the need for further rigorous assessment of the risks associated with the smoke bath practice.

Evaluation of the cytotoxicity, oral toxicity, genotoxicity, and mutagenicity of the latex extracted from Himatanthus drasticus (Mart.) Plumel (Apocynaceae)

ETHNOPHARMACOLOGICAL RELEVANCE

Himatanthus drasticus is a tree popularly known as janaguba. Endemic to Brazil, it is found in the Cerrado and Caatinga biomes, rock fields, and rainforests. Janaguba latex has been used in folk medicine for its antineoplastic, anti-inflammatory, analgesic, and antiallergic activities. However, studies investigating the safety of its use for medicinal purposes are limited.

AIM OF THE STUDY

This study aimed to evaluate the toxicity of the latex extracted from H. drasticus.

MATERIALS AND METHODS

The latex was extracted from H. drasticus specimens by removing a small area of bark (5 × 30 cm) and then dissolving the exudate in water and lyophilizing it. Phytochemical screening was performed by TLC and GC-MS, protein, and carbohydrate levels. Cell viability was performed by the MTT method. Acute oral toxicity, genotoxicity, and mutagenicity assays were performed in mice.

RESULTS

TLC showed the presence of saponins and reducing sugars, as well as steroids and terpenes. The GC-MS analysis of the nonpolar fraction identified lupeol acetate, betulin, and α/β-amyrin derivatives as the major compounds. The latex was toxic to S-180 cells at 50 and 100 μg/mL. No signals of toxicity or mutagenicity was found in mice treated with 2000 mg/kg of the latex, but genotoxicity was observed in the Comet assay.

CONCLUSIONS

H. drasticus latex showed toxicity signals at high doses (2000 mg/kg). Although the latex was not mutagenic to mice, it was genotoxic in the Comet assay in our experimental conditions. Even testing a limit dose of 2000 mg/kg, which is between 10 to 35-fold the amount used in folk medicine, caution must be taken since there is no safe level for genotoxic compounds exposure. Further studies on the toxicological aspects of H. drasticus latex are necessary to elucidate its possible mechanisms of genotoxicity.

Ruscus hypophyllum L. extracts: chemical composition, antioxidant, anticoagulant, and antimicrobial activity against a wide range of sensitive and multi-resistant bacteria

The aim of this study is to evaluate the polyphenolic and flavonoid contents in the leaves extracts of Ruscus hypophyllum. Antioxidant activity was estimated by α,α-diphenyl-β-picrylhydrazyl (DPPH) and 2,2'-azino-bis-3-ethylbenzthiazoline-6-sulfonic acid (ABTS) assays. The anticoagulant activity of Ruscus extracts was evaluated in vitro, using the prothrombin time (PT) and a PTT-activated partial thromboplastin time tests. The antibacterial activity was tested against large number of important medically and resistant bacteria by the broth dilution method. In this study, ethyl acetate and chloroform extracts displayed the highest total phenols contents (74.76 mg EAG/g and 73.89 mg EAG/g, respectively) and flavonoid content 40 and 32.43 mg EC/g, respectively. The GC-MS analysis of ethyl acetate extract confirmed the presence of oxygenated sesquiterpenes and hydrocarbon diterpenes with percentages of 16.41% and 10.72%, respectively, but chloroform extract was rich with, oxygenated monoterpenes, and oxygenated diterpenes, with percentages of 6.19 and 3.27%, respectively. Among tested extracts, ethyl acetate exhibited the best antioxidant and anticoagulant activities. Furthermore, ethyl acetate and chloroform extracts showed important antibacterial activity against resistant bacteria methicillin-resistant Staphylococcus aureus (SARM), Acinetobacter imipenem-resistant (IMP/R), P. aeruginosa imipenem-resistant (IMP/R) and extended-spectrum beta-lactamase producing E. cloacae (BLSE) with minimal inhibitory concentration (MIC) values varying between 0.125 and 0.5 mg/mL.

Evaluation of cytotoxic potential, oral toxicity, genotoxicity, and mutagenicity of organic extracts of Pityrocarpa moniliformis

The objective of this study was to determine the cytotoxicity of organic extracts of P. moniliformis in vitro and identify the acute toxicity and genotoxicity in vivo. The leaves were extracted using three organic solvents (cyclohexane [EP1], ethyl acetate [EP2], and methanol [EP3]). Phytochemical qualitative analysis was performed by thin layer chromatography (TLC). Cytotoxicity tests were performed on human embryonic kidney (HEK) cells and J774 murine macrophages. Acute toxicity in mice was measured after intraperitoneal (ip) administration of 2000 mg/kg, while evaluation of genotoxicity and mutagenicity were assessed using the comet assay and the micronucleus (MN) test, respectively. The TLC analysis of the extracts revealed the presence of flavonoids, triterpenes, steroids, and saponins. In the cytotoxicity assay, extracts EP1 and EP3 altered proliferation of HEK cells, and all organic extracts increased the viability of J774 cells. In the toxicity tests, no deaths or behavioral alterations were observed in mice exposed to the acute dose of the extracts. Although some extracts led to changes in hematological and histological parameters, these results did not indicate physiological changes. In relation to the MN test and comet assay, no significant changes were detected in the DNA of the animals tested with the extracts EP1, EP2, and EP3. Thus, extracts of P. moniliformis were not considered to be toxic and did not induce formation of MN or damage to cellular DNA in the genotoxicity tests.