The MEK/ERK Module Is Reprogrammed in Remodeling Adult Cardiomyocytes

Fetal and hypertrophic remodeling are hallmarks of cardiac restructuring leading chronically to heart failure. Since the Ras/Raf/MEK/ERK cascade (MAPK) is involved in the development of heart failure, we hypothesized, first, that fetal remodeling is different from hypertrophy and, second, that remodeling of the MAPK occurs. To test our hypothesis, we analyzed models of cultured adult rat cardiomyocytes as well as investigated myocytes in the failing human myocardium by western blot and confocal microscopy. Fetal remodeling was induced through endothelial morphogens and monitored by the reexpression of Acta2, Actn1, and Actb. Serum-induced hypertrophy was determined by increased surface size and protein content of cardiomyocytes. Serum and morphogens caused reprogramming of Ras/Raf/MEK/ERK. In both models H-Ras, N-Ras, Rap2, B- and C-Raf, MEK1/2 as well as ERK1/2 increased while K-Ras was downregulated. Atrophy, MAPK-dependent ischemic resistance, loss of A-Raf, and reexpression of Rap1 and Erk3 highlighted fetal remodeling, while A-Raf accumulation marked hypertrophy. The knock-down of B-Raf by siRNA reduced MAPK activation and fetal reprogramming. In conclusion, we demonstrate that fetal and hypertrophic remodeling are independent processes and involve reprogramming of the MAPK.

The effect of globalization of drug manufacturing, production, and sourcing and challenges for American drug safety

Americans benefit from one of the safest drug supplies and one of the highest standards of consumer protection in the world. Over the past decade, though, a general trend toward globalization of the supply chains for finished pharmaceutical products and active pharmaceutical ingredients has created new challenges for the Food and Drug Administration (FDA) in ensuring the safety and quality of the drug supply. Explosive growth in pharmaceutical manufacturing for the US market is particularly evident in the developing regions of Asia. Manufacturing sites in China and India now comprise approximately 40% of all FDA-registered foreign sites, having increased from 30% in 2002. (In 2001, when legislation first went into effect requiring registration of all foreign drug manufacturing sites, 140 registered sites in China listed 797 drug items for potential importation; as of 1 October 2007, that number had grown to 815 registered sites and well over 3,000 listed items.) In total in 2006, the United States received >145,000 line entries of imported drug products from >160 countries, up from only 1,300 line entries in 2000. FDA regulatory oversight resources (e.g., those allocated to inspection and testing of imports) are being challenged to keep up with the explosive growth of imported drugs. (In 2006, the FDA performed inspections at 212 foreign drug firms. This number has remained relatively consistent over the past 6 years, starting at 249 in 2001 and ranging from 190 to 260 on an annual basis.)

[Morphological study of the adenyl cyclase activity of the rat heart in experimental hypoxia and ischemia]

Alteration of the activity and localization of the reaction of adenylcyclase after perfusion of the rat heart with nitrogen, carbon monoxide and after ischaemia was studied by electronmicroscopy. In the first minutes of hypoxia increase of the activity of the adenylcyclase was revealed. After perfusion with nitrogen during three hours and with carbon monoxide during 30 minutes intensity of the reaction was observed to be decreased. In ischaemia decrease of the intensity of the late reaction could not be observed. Alteration of the localization of the reaction in ischaemia and hypoxia was not significant. Administration of reserpine and propanol did not cause any alteration. Authors believe, that increase of the activity of the adenylcyclase may be caused by accumulation of an endogenous catecholamine.