Tuesday, May 18, 2010
Monday, May 10, 2010
Thursday, May 6, 2010
In the April 23, 2010, issue ofImmunity, Drs. Brian Stadinski, John Kappler and George Eisenbarth propose that the unusual and rare presentation of protein fragments (peptides) to the immune system allows autoreactive T cells to escape the thymus and trigger autoimmune disease. The findings could lead to a new strategy for preventing type 1 diabetes.
"The immune system normally deletes dangerous, autoreactive T cells that recognize 'self' peptides, which are a normal part of the organism," said Dr. Kappler, Professor of Immunology at National Jewish Health. "We believe autoreactive T cells in diabetes and other autoimmune diseases escape destruction in the thymus because they never see these poorly presented peptides there. But the T cells do encounter those peptides elsewhere in the body and trigger an autoimmune attack."
Pretty fascinating if the theory is correct. It could also suggest very new areas of research for treatment options.
Tuesday, May 4, 2010
Saturday, May 1, 2010
Many studies have looked at connections between diet, etiology, signs and symptoms associated with inflammatory bowel disease (IBD). Although these connections are apparent to clinicians, they are difficult to prove qualitatively or quantitatively. Enteral feeding and polymeric diets are equally effective at bringing about remission in Crohn’s disease (CD). Parenteral feeding is also effective, although none of these methods is as effective as corticosteroid therapy. However, enteral feeding is preferred in the pediatric population because linear growth is more adequately maintained via this route. Exclusion diets in patients brought into remission using an elemental diet have been shown to maintain remission for longer periods. Studies that aim to isolate culpable food groups have shown that individuals react differently on exposure to or exclusion of various foods. The commonly identified food sensitivities are cereals, milk, eggs, vegetables and citrus fruits. Studies that have looked at gut mucosal antigen behavior have shown higher rectal blood flow, in response to specific food antigens, in those with CD over healthy subjects. Exclusion of sugar shows little evidence of amelioration in CD. Omega 3 fatty acids show promise in the treatment of IBD but await larger randomized controlled trials. Patients frequently notice that specific foods cause aggravation of their symptoms. Whilst it has been difficult to pinpoint specific foods, with advances in the laboratory tests and food supplements available, the aim is to prolong remission in these patients using dietary measures, and reduce the need for pharmacotherapy and surgical intervention.
Samples taken from the colons of humans diagnosed with Crohn's disease also show reduced levels of the antimicrobial peptides, or defenses, regulated by the PPAR-gamma protein, they wrote.
Chamaillard said foods or diets containing conjugated linoleic acid (CLA) can also boost PPAR-gamma activity and have been shown to improve colitis and colitis-associated cancer.
CLA is primarily found in milk and meat products.
"In the short-term, managing the disease is what we are looking at, but it may also be that in the future we could develop a way of stopping it," Chamaillard said.
But he added that curing Crohn's disease would mean being able to identify those at highest risk before they contracted it and then being able to boost PPAR gamma-related defenses to ward it off -- both areas that would need more research.
Of all foods, kangaroo meat may have the highest concentration of CLA. Food products (e.g. mutton and beef) from grass-fed ruminants are good sources of CLA, and contain much more of it than those from grain-fed animals. In fact, meat and dairy products from grass-fed animals can produce 300-500% more CLA than those of cattle fed the usual diet of 50% hay and silage, and 50% grain.