Poly(HexaMethylene Biguanide) hydrochloride (PHMB) CAS No. [32289-58-0] is a particularly effective member of the biguanides antiseptic chemical group, and has been in use since the early fifties in numerous applications. It has been proposed that PHMB be classified as a category 3 carcinogen although PHMB is not genotoxic. It has been hypothesized that PHMB may have epigenetic properties effects, including non-genotoxic modifications of DNA bases, DNA methylation and mitogenic cytokine production. These properties have been assessed in vitro using 3 cell types: Caco-2 cells (from a human colon adenocarcinoma) with a non-functional p53 gene. (∆p53: mut p53), N2-A (Neuro-2A cells, mouse neural cells), the brain being a possible target organ in rodents and HepG2 cells (human hepatocellular carcinoma) with functional p53 gene. From the concentration 1 µg/mL up to 20 µg/mL of PHMB, no effect was observed, either growth stimulation or inhibition. Viability testing using neutral red led to an IC 50 of 20–25 µg/mL after treatment with PHMB for 3 h, whereas the MTT test led to IC50 values of 80 µg/mL, 160 µg/mL and 160 µg/mL respectively for HepG2 cells, Neuro-2A cells and Caco-2 cells. PHMB does not induce significant oxidative stress (production of MDA or lipoperoxidation, nor does it induce hydroxylation of DNA (8-OH-dG) and/or its hypermethylation (m5dC), the latter being strongly implicated in DNA replication and regulation and cell division. PHMB does not induce significant production of mitogenic cytokines such as TNF-α (tumor necrosis factor), interleukins (IL-1 alpha), and the transcription factor nuclear factor kappa B (NF-κB) which can cause either apoptosis or stimulate the growth of transformed cells or tumors. Instead, from concentrations of 20 to 100 µg/mL, PHMB kills cells of all types in less than 3 h. The expression of genes involved in the mechanisms of cell death induced by PHMB, including p53, the pro apoptotic gene bax and others, the anti-apoptotic bcl-2 and caspase-3 has been evaluated by RT-PCR. Finally, the status of GAP-junctions (GJIC) in the presence of PHMB has been determined and appeared to not be significantly affected. Taken together the data show that in vitro PHMB does not exhibit clear and remarkable epigenetic properties except a slight increase of some cytokines and transcription factor at higher concentrations at which cell lysis occurs rapidly.
Background. Herbal medication is a worldwide and ancient practice, mostly in developing countries, where a large part of the population is involved in this practice. Hence, studies must be conducted to evaluate their safety and efficiency to avoid or prevent toxicological risks due to their usage. In Togo, Carissa spinarum is a medicinal plant belonging to Apocynaceae family, used as an aphrodisiac or to heal some ailments including malaria, sickle cell anemia, hypertension, pain, and asthma. Notwithstanding its several ethnomedicinal benefits, just a few toxicological data associated with its chronic use are available. Objective. Therefore, this study aims to assess the toxicity of an ethanolic root extract of Carissa spinarum in Wistar rats. Methods. The 90-day oral toxicity process following OECD TG 408 guidelines is used. Male Wistar rats received Carissa spinarum root hydroethanolic extract at 500 and 1000 mg/kg for 90 days by oral gavage. Body weight changes, hematological and blood biochemical parameters, organ weight changes, malondialdehyde as a lipoperoxidation marker expressed according to tissue proteins, and histopathology of vital organs were assessed. Results. No signs of toxicity or mortality were observed during the 90 days experiment. Hematological parameters have not shown any treatment-related abnormalities. According to biochemical parameters, an increase in the chloride ion level was observed at 1000 mg/kg p<0.01. There was no significant difference between the treated groups and the control group concerning the malondialdehyde concentration, body weight, and organ relative weight. No changes in necropsy and histopathology of vital organs associated with extract treatment were observed. Conclusion. The results indicated that an ethanolic root extract of Carissa spinarum does not cause adverse effects, which can lead to Wistar rats' death after 90-day oral administration at 500 and 1000 mg.
Pesticides are more and more used in African countries. The aim of this study is to evaluate the risk and the impact of pesticides on gardeners health. It is a transversal descriptive study, which referred to vegetable growers, held in Lomé on the period from May 20 to June 5, 2017. Forty-eight (48) growers participated in the study. Men accounted for 70.8 of the study population against 29.2 of women. The level of education was primary (47.9) in the majority of cases. Married people or couples represented 77.1 of cases. Most gardeners (72.9) has no training in the use of pesticides. Pesticides were consistently applied (100), including insecticides (72.7), herbicides (9.1), and fungicides (18.2). Of 20 pesticides collected, 9 (45) were approved by our authorities. Only 43.8 of growers were supplied with pesticides from authorized structures of agricultural products. Branches of plants (79.2) were the spray means of most of the pesticides. Most gardeners (79, 2) did not use personal protective equipment because of lack of resources for 81.6 of them. Water and environment contamination risk by pesticides was known by only 6.3 of gardeners. Among the adverse effects reported, pruritus was the majority in 85.4 of cases followed by headache (70.8), cough (68.8), and muscle pain (64.6). The training of gardeners, monitoring and control of this informal sector, and the monitoring of unregistered pesticides will help to reduce the risk of poisoning of gardeners and consumers of vegetables as well as environmental pollution.
Objective. Mangifera indica Linn, Bridelia ferruginea Benth, and Alstonia boonei De Wild are three plants commonly used in the traditional treatment of urinary tract infections in Benin. This study sets out to assess the cytotoxic and teratogenic effects of extracts of these plants on Artemia salina larvae and hen embryos. Methods and Results. The aqueous and ethanolic extracts were obtained by maceration of the powders in solvents. Larval cytotoxicity was performed on Artemia salina larvae. The teratogenic effect of these plants was evaluated on chick embryos at 100 mg/kg and 300 mg/kg. The extracts were injected on the 7th and 14th days of incubation. The quality of the hatched chicks was evaluated by the Tona score followed by the hematological and the biochemical parameter assays. The extracts did not show cytotoxicity on the larvae. The eggs treated with plant extracts at 300 mg/kg significantly lowered the hatchability rate, except for the Mangifera indica Linn. The chicks obtained were all at the very good quality. Then, no significant variation was observed between hematological parameters except white blood cells. For the biochemical parameters, only ASAT showed some significant variations for a few extracts. It would be important to assess the genotoxicity of the plant extracts to determine more broader toxicity. These data justify the use of these medicinal plants in traditional Beninese medicine and constitute in fact a source of production of anti‐infectious drugs.
Background. Belonging to the family of Combretaceae, the roots of Anogeissus leiocarpus are traditionally used to treat diabetes, wounds, infections, pain, and gastrointestinal diseases. To our knowledge, no genotoxicity assessment of the plant was reported. Hence, this study was designed to evaluate the potential genotoxic and protective effects of extract of Anogeissus leiocarpus roots using the micronucleus test on mice bone marrow cells in vivo. Methods. Three different concentrations (250, 500, and 1000 mg·kg−1) of hydroalcoholic extract of roots of A. leiocarpus were administered daily for 7 days per os to mice, and the genotoxicity was induced by the administration ip of cyclophosphamide. Genotoxicity and cytotoxicity were evaluated by counting, respectively, the number of micronucleated polychromatic erythrocytes and polychromatic erythrocytes to total erythrocytes in the bone marrow of mice. Results. The administration of A. leiocarpus did neither increase the ratio of the polychromatic erythrocyte (PCE) nor the frequency of micronucleated PCE (MNPCE) significantly in the bone marrow cells of the mice, compared to the vehicle control animals. However, a significant increase in the incidence of MNPCE in the bone marrow cell of the cyclophosphamide-treated mice was found. Moreover, in the groups treated with the total extract of A. leiocarpus at different doses plus cyclophosphamide, there was a significant decrease in MNPCEs compared to the positive controls, in a dose-dependent manner. Conclusion. This first finding reports that the extract of A. leiocarpus was neither genotoxic nor cytotoxic. However, it shows a protective effect against the genotoxicity and cytotoxicity induced by cyclophosphamide.