New culprit for viral infections among elderly -- an overactive immune responsefrom the leaflady: Nettle
ScienceDaily (2009-11-30) -- Researchers have found that exaggerated responses of the immune system explain why the elderly succumb to viral infections more readily than younger people. The study bucks the general belief that declining immune responses are to blame for susceptibility to viral infections. ... > read full article
"Anti-inflammatoryexcerpt above from Notes on Nettle at leaflady.org
Stinging nettle demonstrates anti-inflammatory activity in experimental situations. The extract partially inhibits the activity of 5-lipoxygenase and shows a concentration dependent inhibition of the synthesis of cyclooxygenase derived reactions.(2) (Note: these are the same enzymes that aspirin inhibits). A new class of drugs (called Cox2 inhibitors) aimed specifically at modulating cyclooxygenase enzymes is one of the new darling in the pharmaceutical industry.
Stinging nettle (both the leaf and root) also appears to prevent the over stimulation of proinflammatory cytokines like tumor necrosis factor-alpha and interleukin-1 beta. Cytokines can be thought of in simple terms as immune system messengers. And while a discussion of these proinflammatory cytokines and immune system balance is beyond the scope of this column, cytokine balance is a growing area of interest in medicine.
In fact, virtually all immune disorders (from HIV, to cancer, to autoimmune diseases), allergic conditions (like asthma and allergies) and even obesity/insulin resistance have characteristic imbalances in cytokine levels as part of the functional derangement occurring at a metabolic level. Between the lipoxygenase, cyclooxygenase, and cytokine modulating activities of this plant, stinging nettle is literally a treasure chest of unexplored potential.
Anti-viral and Immune Balancing
UDA Superantigen Stinging nettle actually contains a "super lectin" called UDA superantigen (UDA for short). For those interested, UDA appears to be an N-acetylglucosamine specific lectin. Evidence indicates that this super lectin can inhibit a range of viruses including those responsible for HIV, colds, and influenza.(4)
UDA is also T-cell mitogen, distinguishable from classical T-cell lectin mitogens, by its ability to discriminate a particular population of CD4+ and CD8+ T-cells, as well as its capacity to induce an original pattern of T-cell activation and cytokine production.(5) Basically, what this means is that unlike most things that stimulate the immune system only toward greater activity, the super lectin in stinging nettles appears to stimulate the immune system to be in balance.(6)
While studies in humans are lacking (and would be extremely desirable), the UDA super lectin has been shown to prevent the progression of experimentally induced systemic lupus erythematosus-like pathology in mice. In the experiment, UDA-lectin treated animals did not develop overt clinical signs of lupus and nephritis (kidney disease). UDA was also shown to alter the production of autoantibodies in a sex-dependent manner.(14)"