Interleukin information by Ray Sahelian, M.D.

Interleukins are a group of cytokines that were first noticed to be released by white blood cells (leukocytes, hence the -leukin) as a means of communication, hence the term 'inter.' Further research indicated that nterleukins are made by a wide variety of bodily cells. There are many types of interleukins, and they are numbered as interleukin 1, interleukin 2, etc.

Diet and interleukin production
Increased intakes of dietary alpha linolenic acid elicit antiinflammatory effects by inhibiting interleukin 6, interleukin  1 beta, and TNF-{alpha} production in cultured peripheral blood mononuclear cells. Changes in PBMC alpha linolenic acid and eicosapentaenoic acid (derived from dietary ALA) are associated with beneficial changes in TNF-{alpha} release. Thus, the cardioprotective effects of alpha linolenic acid are mediated in part by a reduction in the production of inflammatory cytokines.

Interleukin and food allergy
Interleukin-12 may protect against food allergies. A British team at the Institute of Food Allergy Research in Norwich noted that interleukin-12 is absent during the body's allergic response. "We have identified a molecule that is very important for the regulation of immune response and for the first time clearly represents a potential target for the therapy of allergy. This is currently under investigation," lead researcher Claudio Nicoletti said in a prepared statement. The Interleukin-12 molecule is made by white blood cells. These cells help regulate the body's immune response to foreign materials, including food proteins. Researchers compared cells in the gut and spleen of mice with and without food allergies. Cells in the allergic mice did not make interleukin-12. The discovery helps explain how "a food protein can be perfectly harmless to one person and lethal to another," Nicoletti said. "We have identified the missing molecule that normally keeps immune responses under control." July 2007 issue of the Journal of Allergy and Clinical Immunology.

Interleukin 7 and HIV AIDS
Dr. Paolo Lusso and colleagues at the National Institutes of Health, National Institute of Allergy and Infectious Diseases looked at the role played by interleukin 7 in averting the death of T cells, a kind of white blood cell important to the immune system.  They used blood samples from 24 HIV-infected people. They added interleukin 7 to the blood samples and then gauged the survival of T cells. Interleukin 7 is a substance important in maintaining proper functioning of the immune system. The actual patients themselves were not treated with interleukin 7. The samples with interleukin 7 displayed lower levels of T cell death. The benefits differed from sample to sample based on the person's stage of infection. The researchers believe interleukin 7 potentially could be used alongside existing AIDS drugs to bolster the immune system. Existing AIDS drugs can keep the virus at bay for years, but damage to the immune system commonly persists even after years of such treatment. The next step is a study in which monkeys with the simian equivalent of HIV are given interleukin 7 to see if it blocks immune system dysfunction and immune cell depletion.

Quercetin and Interleukin 6
Effects of quercetin on angiotensin II induced interleukin-6 in vascular smooth muscle cells
Zhong Yao Cai. 2006 Jul;29(7):683-6. Department of Pharmacology, Xi'an Jiao University of Medicine, China.
To observe the effects of quercetin on angiotensin induced interleukin-6 (IL-6) in vascular smooth muscle cells (VSMCs). VSMCs were isolated from the thoracic aorta of Sprague-Dawley rats and were stimulated with different doses of angiotensin II. The production of IL-6 in supernatant of quercetin treated cultures was detected by ELISA. In parallel, interleukin-6 mRNA level was measured by RT-PCR. angiotensin II induced a marked increase of interleukin-6 in a dose- and time-dependent manner in the culture of VSMCs. Quercetin inhibited the production of Ang II -induced interleukin-6 in the culture in a dose-dependent manner. Similarly, the result with RT-PCR indicated that the expression of interleukin-6 mRNA induced by angiotensin II for 24h was down-regulated by quercetin. CONCLUSION: It demonstrates that quercetin possesses a inhibition of angiotensin II-induced production of IL-6 in VSMCs. Moreover, quercetin also down regulates the expression of interleukin-6 mRNA, suggesting the action of quercetin on interleukin-6 release induced by angiotensin II in VSMCs may underlie its anti-inflammatory properties.