Evaluation of the genotoxic and antigenotoxic potential of lignin-derivative BP-C2 in the comet assay in vivo

Determination of genoprotection against cyclophosphamide induced toxicity in bone marrow of Swiss albino mice by Moringa oleifera leaves and Tinospora cordifolia stem

The present study aimed to determine the genoprotective activity and safety of Moringa oleifera leave and Tinospora cordifolia stem extracts against cyclophosphamide (CP)-induced genotoxicity utilizing Swiss albino mice. Animals were divided into 14 groups for subacute treatment with either M. oleifera or T. cordifolia extracts daily for 28 days. The extract doses selected were 100, 200 or 400 mg/kg b.w administered orally alone or combined with CP (50 mg/kg b.w. intraperitoneally daily for 5 days). Analyses performed included the comet assay, micronucleus test (MN) in bone marrow cells and sperm head abnormality assay (SHA). M. oleifera and T. cordifolia extracts induced no significant genotoxic effects on somatic and germ cells. In contrast, for all cells examined M. oleifera and T. cordifolia extracts inhibited DNA damage initiated by CP. Taken together data demonstrated that both plant extracts did not exhibit marked genotoxic effects but displayed potential chemoprotective properties against CP-induced genotoxicity in Swiss mice.

Polyphenols as anticancer agents: Toxicological concern to healthy cells

Polyphenols are a group of diverse chemical compounds present in a wide range of plants. Various biological properties such as antiallergic, antiviral, antibacterial, anticarcinogenic, antiinflammatory, antithrombotic, vasodilatory, and hepatoprotective effect of different polyphenols have been reported in the scientific literature. The major classes of polyphenols are flavonoids, stilbenoids, lignans, and polyphenolic acids. Flavonoids are a large class of food constituents comprising flavones, isoflavanones, flavanones, flavonols, catechins, and anthocyanins sub-classes. Even with seemingly broad biological activities, their use is minimal clinically. Among the other concurrent problems such as limited bioavailability, rapid metabolism, untargeted delivery, the toxicity associated with these polyphenols has been a topic of concern lately. These polyphenols have been reported to result in different forms of toxicity that include organ toxicity, genotoxicity, mutagenicity, cytotoxicity, etc. In the present article, we have tried to unravel the toxicological aspect of these polyphenols to healthy cells. Further high-quality studies are needed to establish the clinical efficacy and toxicology concern leading to further exploration of these polyphenols.

Geroprotective potential of in vitro bioactive compounds isolated from yarrow (Achilleae millefolii L.) cell cultures

Introduction. There is an urgent need for geroprotectors that prevent premature aging, especially antioxidants of plant origin. Due to the shortage of medicinal plant materials, scientists look for alternative sources of bioactive compounds of phenolic nature, for example, cell cultures and organs of higher plants. This paper describes a study of the geroprotective potential of in vitro bioactive compounds isolated from yarrow (Achilleae millefolii L.) cell cultures. Study objects and methods. Callus, suspension and hairy root cultures of A. millefolii were obtained by in vitro cultivation on modified nutrient media. High performance liquid chromatography (HPLC) was used to analyze the composition of the cell cultures and ethanol extracts. The extracts’ antimicrobial activity was studied by the disk diffusion method and their antioxidant activity was measured based on titration of a potassium permanganate solution. Results and discussion. The biomass of all yarrow cell cultures contained essential oils, flavonoids, glycosides, phenolic acids, carotenoids, as well as vitamins C and E. The suspension culture had a higher content of essential oils, flavonoids and glycosides than the callus and hairy root cultures. The extracts of the A. millefolii suspension culture also contained geroprotectors – phenylpropanoids, flavonoids, and simple phenols, with a prevalence of caffeic acid, cynaroside, 4,5-dicofeylquinic acid, apigenin, and luteolin. In addition, HPLC revealed the presence of cumic aldehyde, umbelliferone, 3-caffeylquinic acid, and caffeic acid – the bioactive compounds previously not reported in yarrow. In vitro experiments with the extracts proved their antimicrobial and antioxidant activity. Conclusion. The complex of bioactive compounds isolated from the biomass of yarrow suspension culture provides this plant with potential geroprotective properties. Thus, yarrow can be used to create nutraceuticals that prevent premature aging.

Safety aspects of kraft lignin fractions: Discussions on the in chemico antioxidant activity and the induction of oxidative stress on a cell-based in vitro model

Lignin is a complex phenolic biopolymer present in plant cell walls and a by-product of the cellulose pulping industry. Lignin has functional properties, such as antioxidant activity, that make it a potential natural active ingredient for health-care products. However, not all safety aspects of lignin fractions have been adequately investigated. Herein, we evaluated the antioxidant and genotoxic potential of two hardwood kraft lignins (F3 and F5). The chemical characterization of F3 and F5 demonstrated their thermal stability and the presence of different phenolic units, while the DPPH assay confirmed the antioxidant activity of these lignin fractions. Despite being antioxidants in the DPPH assay, F3 and F5 were capable of generating intracellular reactive oxygen species (ROS) and subsequently causing oxidative DNA damage (Comet assay) in HepG2 cells. The biological relevance of the DPPH assay might be uncertain in some cases; therefore, we suggest combining in chemico tests with biological system-based tests to determine efficacy and safety levels of lignins and define appropriate applications of lignins for consumer products. Moreover, kraft lignins obtained by acid precipitation may pose risks to human health; however, as genotoxicity is not the sole endpoint of toxicity required in hazard assessments, additional toxicological evaluations are needed.