Pg and its chemical components possess various pharmacological and toxicological properties including antioxidant, anti-inflammatory (by inhibiting pro-inflammatory cytokines), anti-cancer and anti-angiogenesis activities. They also show inhibitory effects on invasion/motility, cell cycle, apoptosis, and vital enzymes such as cyclooxygenase (COX), lipooxygenase (LOX), cytochrome P450 (CYP450), phospholipase A2 (PLA2), ornithine decarboxylase (ODC), carbonic anhydrase (CA), 17beta-hydroxysteroid dehydrogenase (17β-HSDs) and serine protease (SP). Furthermore, they can stimulate cell differentiation and possess anti-mutagenic effects. Other studies have also shown the protective effects of Pg on the cardiovascular system, including reduction of LDL and cholesterol, anti-hypertension action by combating OS induced by diabetes and angiotensin II, reduction of carotid arterial stenosis and increase of endothelial nitric oxide (NO) syntheses and suggest the Pg as part of a heart-healthy diet through inhibiting of OS mechanism. Acute inflammation is a beneficial host response for prevention of tissue injury, but it may also cause immune-associated diseases such as rheumatoid arthritis, inflammatory bowel disease and cancers. Interestingly, Pg, Pg has been shown to inhibit inflammation by different mechanisms. Pg possesses inhibitory effects on different type of cancers such as prostate, breast, colon, and lung cancers. Different mechanisms have been outlined for pomegranates anti-cancer activities in these studies.
Apoptosis is the process of programmed cell death, which is a useful marker for predicting tumor response after anti-cancer treatment. Pg causes apoptosis by different mechanisms. PE has been found to induce apoptosis by increasing caspase-3 activity in a mouse mammary cancer cell line (WA4). In addition, Pg extracts and punic acid, an omega-5 long chain poly unsaturated fatty acid derived from Pg, have been shown to induce apoptosis in both an estrogen in sensitive breast cancer cell line (MDA-MB-231) and an estrogen sensitive cell line developed from MDA-MB-231 cells (MDA-ERalpha7) through lipid peroxidation and the PKC (Protein kinase C) signaling pathway. Cellular differentiation, in developmental biology, is the process by which a less specialized cell becomes a more specialized cell type. Study has shown that Pg stimulates the differentiation of osteoblastic MC3T3-E1 cells and affects the function of these cells. Pg seed oil (but not aqueous extracts of fermented juice, peel or seed cake) has been shown to stimulate keratinocyte proliferation in monolayer culture, without effecting fibroblast function, and as a result facilitates skin repair and promotes regeneration of dermis and epidermis. A mutagen is a physical orchemical agent that alters the genetic material of an organism, usually DNA, permanently and thus increases the frequency of mutations above the natural background level Mutagenicity is the capacity of a chemical or physical agent to cause such permanent change. It has been shown that Pg peel fractions, especially methanol, has anti- mutagenic activities as was detected by the Ames Salmonella/microsome assay against sodium azide (NaN3), methyl methane sulphonate (MMS), 2-aminofluorene (2-AF), and benzo(a)pyrene (B(a)P) induced mutagenicity in Salmonella typhimurium (TA97a, TA98, TA100 and TA102) tester strains. Methanolic extract of Pg (15 mg/plate) shows the highest anti-mutagenic activity in TA 100 cells.