Recent News and Articles on the Keywords: key + enzyme + associated  Related to the article below (Last Update: 8/5/2008)

Business Wire (press release) Hollis-Eden Pharmaceuticals Commences Phase I/II Clinical Trial ... Business Wire (press release), CA - For example, Celebrex?, a commonly used anti-inflammatory drug for RA that inhibits the cox-2 enzyme currently has annual sales in excess of $2 billion. ...HEPH Lexicon Pharmaceuticals' Drug Candidate for Irritable Bowel ... MarketWatch - Jul 29, 2008 The target of LX1031 is tryptophan hydroxylase (TPH), a key enzyme in the synthesis of serotonin. Lexicon discovered that mice lacking TPH1, ...LXRX AtheroGenics Reports Positive Results From ANDES Phase 3 Clinical ... MarketWatch - Jul 31, 2008 One patient in the 150mg arm and two patients in the 75mg arm had unexplained liver enzyme elevations of greater than five times the upper limit of normal. ...AGIX Viagra helpful to women on antidepressants, study finds Los Angeles Times, CA - Jul 23, 2008 The drug blocks an enzyme that inhibits blood flow, which, in the case of men, allows more blood to flow to the penis. In women, the drug increased ... Hepatitis C Virus May Need Enzyme's Help To Cause Liver Disease Science Daily (press release) - Jul 9, 2008 ScienceDaily (July 9, 2008) ? A key enzyme may explain how hepatitis C infection causes fatty liver -- a buildup of excess fat in the liver, which can lead ... Kane Biotech Meets Key Milestone in DispersinB(TM) Manufacturing ... FOXBusiness - Jul 7, 2008 DispersinB(TM) is a novel antibiofilm enzyme capable of both inhibiting and dispersing bacterial biofilms. Kane Biotech has received a patent from the US ...CVE:KNE - TSE:X - OTC:CMTX ABF and Mascoma Corporation collaborate on enzymes in Biomass ... Food Ingredients First (press release), Netherlands - Jul 25, 2008 Our long time investment in Thermostable enzymes, developed for other industries, was a key reason for Mascoma to choose us as a partner. ...LON:ABF Scientists discover key patterns in the packaging of genes Hindu, India - Jul 12, 2008 First they used an enzyme to cut the DNA into short segments, which remained attached to histone "spools." For each of 39 distinct histone modifications, ... HEALTH MATTERS: Keeping kidneys healthy Cranbury Press, NJ - Jul 31, 2008 The most common class of drugs used to treat chronic kidney disease are called angiotensin converting enzyme (ACE) inhibitors, which are used to control ... Process Used By Microbes To Make Greenhouse Gases Uncovered Science Daily (press release) - Jul 8, 2008 ?This enzyme is the key to the whole process of methanogenesis from acetic acid,? Krzycki said. ?Without it, this form of methanogenesis wouldn?t happen. ...

Lack of Key Enzyme Associated with Development of Rare Tumor

Researchers at the National Institutes of Health have discovered that a rare tumor of the adrenal glands appears to result from a genetic deficiency of an important enzyme. The enzyme is one of a class of enzymes involved in halting a cell’s response to hormones and appears to stop cells from dividing.

The study, published in Nature Genetics, was conducted by researchers in NIH’s National Institute of Child Health and Human Development. The NIH group collaborated with scientists from the Mayo Clinic, the Cochin Institute in Paris, the University of Paris, Ohio State University in Columbus, and the Universitaire Vaudois in Lausanne, Switzerland, in collecting samples from patients with rare adrenal disorders. Scientists from Sapio Sciences in York, Pennsylvania, assisted in the analysis of the data.

In conducting the study, the researchers used gene arrays to analyze the DNA of patients with a rare tumor of the adrenal glands, known as micronodular adrenocortical hyperplasia, explained the study’s senior author, Constantine Stratakis, M.D., D(Med)Sc, Chief of NICHD’s Section on Endocrinology and Genetics. The researchers also used the technology to analyze samples of the patients’ tumors.

The researchers found four patients who had mutant copies of a gene that contains the information for Phosphodiesterase 11A (PDE11A). Phosphodiesterases are a family of enzymes involved in “switching off” a cell’s response to hormones, Dr. Stratakis explained.

For a hormone to affect the cell, it must first bind to a molecule, or receptor, on the cell’s surface, analogous to how a key fits into a lock. This action triggers the cell to produce substances known as cyclic nucleotides. These function as “second messengers,” often stimulating the cell to begin an activity. In the case of adrenal cells, cyclic nucleotides, such as cyclic AMP and cyclic GMP, may stimulate cell growth or other activities. Once the activity has ended, phosphodiesterases degrade the cyclic nucleotides, thereby halting the cell’s response to the hormone.

other kinds of cells in the body. Because they lacked PDE11A, the patients’ adrenal cells had higher levels of cyclic nucleotides. The researchers believe that these higher cyclic nucleotide levels led to the formation of tumors.

The gene for PDE11A contains the information needed to make 4 slightly different forms of the enzyme. The form of the enzyme that was mutated in the patients who took part in the study was found in large amounts in normal adrenal glands and in even larger amounts in normal prostate glands, Dr. Stratakis added. Other forms of PDE11A are found in several other tissues, including the testes, skeletal muscle, and the heart.

Dr. Stratakis noted that although the evidence associating the mutation in the gene for PDE11A to the development of adrenal tumors was very strong, the study was not capable of proving that the mutation actually caused the tumors.

In their article, the researchers wrote that drugs used to treat erectile dysfunction interfere with the functioning of PDE11A. The researchers noted that PDE11A “is partially inhibited” by the drug tadalafil and “weakly” inhibited by sildenafil. They added that there are no reports in the medical literature of malfunctioning adrenal glands or increased adrenal cell growth in users of these drugs.

“However, detailed clinical studies addressing this potential complication are currently lacking,” they wrote.

Dr. Stratakis and his colleagues are currently planning studies to determine if differences in the gene for PDE11A might influence an individual’s cancer risk.

The NICHD sponsors research on development, before and after birth; maternal, child, and family health; reproductive biology and population issues; and medical rehabilitation. For more information, visit the Institute’s Web site at http://www.nichd.nih.gov/.

The National Institutes of Health (NIH) — The Nation's Medical Research Agency — includes 27 Institutes and Centers and is a component of the U.S. Department of Health and Human Services. It is the primary federal agency for conducting and supporting basic, clinical and translational medical research, and it investigates the causes, treatments, and cures for both common and rare diseases. For more information about NIH and its programs, visit www.nih.gov.