Aging immune system function

It is known that zinc and cooper play an important role in immune system functioning (Kelley et al., 1995 Skalny and Rudakov, 2004 Zinc, 2001). Deficiency of these metals causes immune system dysfunctions. Recently these dysfunctions are seen to be widely distributed, especially in children. It is known also that sensitivity of the immune system to external influences differs in different age periods and it was found (Evstafyeva et al., 2002) that the influence of toxic metals is more significant in 7-11-year-old urbanized children. At the same time zinc and cooper deficiency was found in 1-6-year-old children, zinc deficiency and copper lowered contents, in... 

The ozone layer around the Earth has provided us all a natural ring of protection from harmful UV radiation. However, multiple anthropogenic activities have acted as barriers and often caused damage to this shield. Less protection from UV light will, over time, lead to increased health problems and crop damage. Major health problems linked to overexposure to UV radiation by the depletion of ozone include skin cancer (melanoma and nonmelanoma), premature aging of the skin and other skin problems, cataracts and other eye damage, and suppression of normal immune system function.29... 

Cancer, or neoplasia, which occurs in one of every four individuals and results in the death of one of every five individuals in the United States, is a complex disease with multiple causes. Many intrinsic and extrinsic factors influence the development of cancer. Intrinsic or host factors include age, sex, genetic constitution, immune system function, metabolism, hormone levels, and nutritional status. Extrinsic factors include substances eaten, drunk, or smoked workplace and environmental (air, water, and soil) exposures natural and medical radiation exposure ... 

Wander RC, Hall JA, Gradin JL, Du SH, Jewell DE. The ratio of dietary (n-6) to (n-3) fatty acids influences immune system function, eicosanoid metabolism, hpid peroxidation and vitamin E status in aged dogs. J Nutr. 1997 127 1198-205. 

Weyand CM, Brandes JC, Schmidt D, Fulbright JW, Goronzy JJ. Functional properties of CD4+ CD28-T-cells in the aging immune system. Meeh Ageing Dev 1998 102 131-147. 

The ideal of any vaccine is to provide life-long protection to the individual against disease. Immunological memory (Chapter 14) depends upon the survival of cloned populations of small B and T lymphocytes (memory cells). These small lymphocytes have a lifespan in the body of ca. 15-20 years. Thus, if the immune system is not boosted, either by natural exposure to the organism or by re-immunization, then immunity gained in childhood will be attenuated or lost completely by the age of 30. Those vaccines which provide only poor protection against disease have proportionately reduced time-spans of effectiveness. Yellow fever vaccination, which is highly effective, must therefore be repeated at 10-year intervals, whilst typhoid vaccines are only effective for 1-3 years. Whether or not immunization in childhood is boosted at adolescence or in adult life depends on the relative risks associated with the infection as a function of age. 

The sympathetic nervous system (SNS) and the hypothalamic-pituitary axis work together as important modulators of the immune system after exposure to stressors. Norepinephrine (NE) and epinephrine (EPI) (catecholamines from the SNS) and neuroendocrine hormones modulate a range of immune cell activities, including cell proliferation, cytokine and antibody production, lytic activity, and migration. This chapter will focus on these two major pathways of brain-immune signaling, briefly summarizing the evidence for SNS and hypothalamic-pituitary-adrenal (HPA) modulation of immune function, their influence on immune-mediated diseases, immune modulation in aging, and early life influences on these pathways. 

Some authors claim that liposaccharides can depress the content of TNF-a and increase the activity of superoxide dismutase (SOD) and catalase, thus—via mediators—they can affect the immune system (Can et al. 2003). It has been demonstrated that the NF-p transcription factor, (highly sensitive to the redox potential in its environment), which regulates synthesis of many mediators—cytokines, associated with inflammatory condition and the phenomenon of adhesion of cells— becomes deregulated in old age. Defense functions in such cases (and primarily in arthritis and arthritis-related conditions) are said to be performed by antioxidants (including a-lipoic acid), which can modulate the activity of monocytes and inhibit changes caused by deregulating of the transcription factor NF-kB under the influence of redox conditions in elderly people (Lee and Hughes 2002). 

---