Bacterial protein mimics its host to disable a key enzyme
NEW YORK Helicobacter pylori, an infection that causes gastric ulcers and cancers of the gut, may be influenced by a bacterial protein that influences the structure of stomach tissue, scientists found.
C. Erec Stebbins, head of the Laboratory of Structural Microbiology at Rockefeller University, Research Associate Dragana Nesic and colleagues deciphered the atomic structure of an important segment of the large H. pylori protein CagA as it attached to a human enzyme called MARK2. MARK2 (also known as PAR1b) regulates processes, including the “tight junctions” that form between cells, packing stomach tissue together.
The researchers concluded that the protein’s make-up was similar to a human protein, but instead, it disrupted different cell functions. By injecting a protein into the stomach lining that mimics a native protein but has its opposite effect, the bacterium shuts down a process that aids the development of the stomach lining, scientists said.
H. pylori is known for its direct involvement in gastric ulcers and tumors, and the activity of the enzyme that CagA effectively shuts down has been implicated in other disorders, including Alzheimer’s disease and obesity. Understanding more about how CagA works is potentially useful for treating a litany of medical problems, researchers noted.
“Evolution has created a bacterial protein — CagA — that looks exactly like one of ours, and the enzyme that interacts with it is totally fooled,” Stebbins said. “CagA binds to it so tightly that the enzyme gets locked in this trapped, dead state and is unable to do what it usually would.
“What we hope is that now we’ve opened up CagA by showing how we can take this huge protein on,” Stebbins added. “We would love to see this kind of research accelerate because there is a lot more we need to understand about how it works.”
Tylenol Arthritis caplet recall becomes a bigger headache
NEW YORK Johnson & Johnson has expanded its voluntary recall of Tylenol Arthritis caplets in the wake of consumer reports of a moldy smell that can cause nausea and sickness. The recall now includes all product lots of the Arthritis Pain caplet 100-count bottles with the red EZ-Open cap.
Prior to this, the company had recalled five lots of the product in November, citing similar reasons, with user complaints of nausea, stomach pain, vomiting and diarrhea.
According to J&J, the odor is coming from trace amounts of 2,4,6-tribromoanisole — a chemical used to treat wooden pallets that transport and store packaging materials — which is believed to be the result from the breakdown of another chemical used in the manufacture of the drug.
To date, the side effects have been “temporary and non-serious,” although the health effects of the compound have not been studied.
The recall only affects the specific lots reported, and does not extend to any other Tylenol pain products.
J&J is moving its production of Tylenol Arthritis Pain caplets 100-count to another plant, and plans to reintroduce the product in January.
J&J is advising consumers seeking a refund or replacement to call (888) 222-6036.
CVS Caremark appoints new president of PBM business
NEW YORK If there was any doubt as to the value CVS Caremark places on personalized medicine, that doubt no longer should exist.
Clearly, the company believes that one area its PBM can create real value for payers is within pharmacogenomics or personalized medicine. Not only has CVS Caremark tapped Per Lofberg, co-founder of genetic benefit management company Generation Health, to serve as the PBM president, but it also has upped its stake in Generation Health.
Generation Health will continue to operate as a separate business from CVS Caremark, but CVS Caremark will have financial and strategic ties to the company, as well as representation on its board of directors.
The moves are undoubtedly in line with CVS Caremark’s efforts to move well beyond a traditional retail pharmacy role and into a pharmacy healthcare service company aimed at improving health outcomes and lowering healthcare costs.
PGx clinical services are expected to be introduced to CVS Caremark’s PBM clients in the second quarter 2010, and will initially focus on testing programs for medications in the areas of oncology, cardiovascular medicine and HIV, among others. In addition, the partnership opens the door for future programs to test for certain hereditary diseases.
According to Generation Health, genomic testing represents a $3 billion market that is growing 45% annually. There are at least 100 new tests added each year and they are usually priced at several hundred dollars each.