Free Radicals: Health Implications and their Mitigation by Herbals.

Free radicals pose serious threat to tissues and vital organs, especially membrane lipids, proteins and nucleic acids of cells. Overproduction of reactive oxygen/ nitrogen species (ROS/RNS) and other related radicals lead to oxidative stress which has been implicated in aging and a number of diseases. Free radicals react with biomolecules and cause lipid peroxidation, loss of enzyme activity, mutation and carcinogenesis. A number of degenerative diseases including cardiovascular disease, diabetes, and adverse hepatic conditions have been attributed to accumulation of free radicals. Diseases resulting from radical overload might also lead to different types of cancers. However free radicals at low or moderate levels are vital to human health. ROS and RNS produced in a well regulated manner help maintain homeostasis at the cellular level in the normal healthy tissues and play an important role as signaling molecules. Cellular antioxidant enzyme systems including superoxide dismutase, catalase, glutathione peroxidases/reductase, peroxiredoxins along with non enzymatic antioxidants viz., tocopherols, vitamin C and glutathione etc., apart from several dietary components protect cells and organisms from the lethal effects of excessive ROS production. Natural products of plant origin have been used in traditional medicine for the treatment of diseases resulting from radical overload. The diversity of phytochemicals such as polyphenols, flavonoids, carotenes and saponins etc. present in plants and dietary components provide drug leads for the development of novel therapeutic agents. This review deals with the components of free radical biology, their adverse consequences in humans and amelioration of diseases by botanical therapeutics.

Cell cycle inhibitory activity of Piper longum against A549 cell line and its protective effect against metal-induced toxicity in rats.

Anticancer potential of Piper longum fruit against human cancer cell lines (DU-145 prostate, A549 lung, THP-1 leukemia, IGR-OVI-1 ovary and MCF-7 breast) as well as its in vitro and in vivo biochemical efficacy in AlCl3-induced hepatotoxicity were evaluated in the rats. Dried samples were extracted with several solvents using soxhlet apparatus. Flavonoid content in chloroform, benzene, ethyl alcohol and aqueous extracts of fruit was 19, 14, 12 and 11 μg quercetin equivalent/mg of sample, respectively. Hexane extracts exhibited 90-92% cytotoxicity against most of the test cell lines (A549, THP-1, IGR-OVI-1 and MCF-7), while benzene extract displayed 84-87% cytotoxicity against MCF-7, IGR-OV-1 and THP-1 cell lines. Among extracts, hexane, benzene and acetone extracts demonstrated considerable cytotoxicity (91-95%) against A549 (lung cancer) cell line in Sulforhodamine B dye (SRB) assay. Cell cycle analysis revealed that hexane, benzene and acetone extracts produced 41, 63 and 43% sub-G1 DNA fraction, demonstrating cell cycle inhibitory potential of these extracts against A549 cell line. Chloroform, ethyl alcohol and aqueous extracts displayed 71, 64 and 65% membrane protective activity, respectively in lipid peroxidation inhibition assay. P. longum fruit extracts also ameliorated AlCl3-induced hepatotoxicity, as indicated by alterations observed in serum enzymes ALP, SGOT and SGPT activity, as well as creatinine and bilirubin contents. In conclusion, study established the cytotoxic and hepatoprotective activity in P. longum extracts.