Synergistic Impact of Xanthorrhizol and -δ-Tocotrienol on the Proliferation of Murine B16 Melanoma Cells and Human DU145 Prostate Carcinoma Cells.

Isoprenoids suppress the mevalonate pathway that provides prenyl groups for the posttranslational modification of growth-regulating proteins. We hypothesize that xanthorrhizol and -δ-tocotrienol synergistically suppress the growth of murine B16 melanoma and human DU145 prostate carcinoma cells. Xanthorrhizol (0-200 µmol/L; half maximal inhibitory concentration [IC] = 65 µmol/L) and -δ-tocotrienol (0-40 µmol/L; IC = 20 µmol/L) each induced a concentration-dependent suppression of the proliferation of B16 cells and concurrent cell cycle arrest at the G1 phase.

Potential roles of vitamin E in age-related changes in skeletal muscle health.

Skeletal muscle disorders including sarcopenia are prevalent during the complex biological process of aging. Loss of muscle mass and strength commonly seen in sarcopenia is induced by impaired neuromuscular innervation, transition of skeletal muscle fiber type, and reduced muscle regenerative capacity, all attributable to chronic inflammation, oxidative stress, and mitochondrial dysfunction. Current literature suggests that vitamin E molecules (α-, β-, γ-, δ-tocopherols and the corresponding tocotrienols) with their antioxidant and anti-inflammatory capabilities may mitigate age-associated skeletal dysfunction and enhance muscle regeneration, thus attenuating sarcopenia.

Mevalonate deprivation mediates the impact of lovastatin on the differentiation of murine 3T3-F442A preadipocytes.

The statins competitively inhibit 3-hydroxy-3-methylglutaryl coenzyme A (HMG CoA) reductase activity and consequently the synthesis of mevalonate. The use of statins is associated with insulin resistance, presumably due to the impaired differentiation and diminished glucose utilization of adipocytes. We hypothesize that mevalonate is essential to adipocyte differentiation and adipogenic gene expression.

Mevalonate depletion mediates the suppressive impact of geranylgeraniol on murine B16 melanoma cells.

The diterpene geranylgeraniol (all trans-3,7,11,15-tetramethyl-2,6,10,14-hexadecatetraen-1-ol) suppresses the growth of human liver, lung, ovary, pancreas, colon, stomach and blood tumors with undefined mechanisms. We evaluated the growth-suppressive activity of geranylgeraniol in murine B16 melanoma cells. Geranylgeraniol induced dose-dependent suppression of B16 cell growth (IC(50) = 55 ± 13 µmol/L) following a 48-h incubation in 96-well plates.

Plasma copper, zinc, and selenium levels and correlates with metabolic syndrome components of lebanese adults.

Zinc, copper, and selenium statuses were reported to be linked to the development of chronic diseases, especially coronary heart disease (CHD). Metabolic syndrome, a known CHD risk factor, was found to be highly prevalent in Lebanon. Nevertheless, no data are available on the statuses of plasma zinc, copper, and selenium, especially in terms of their relation to the components of the metabolic syndrome.