Nutrition and Age‐Associated Inflammation: Implications for Disease Prevention

Abstract

Accumulating evidence suggests that aging is associated with dysregulated immune and inflammatory responses. Investigation into the cellular and molecular mechanisms underlying this phenomenon suggests that an up-regulated cyclooxygenase (COX)-2 expression, and resulting increase in production of prostaglandin E(2) (PGE(2)), is a critical factor. Macrophages from old mice have significantly higher levels of PGE(2) production compared with those from young mice, a result of increased COX-2 expression and protein levels leading to increased COX enzyme activity. Furthermore, studies suggest that the age-associated increase in macrophage PGE(2) production is due to ceramide-induced up-regulation of nuclear factor-kappa B activation. Such processes may also occur in cell types other than macrophages, lending further insight into potential mechanisms of age-related diseases. Moreover, the excess PGE(2) induces harmful effects in other cell types such as T cells and adipocytes through the negative crosstalk between macrophages with other cells, resulting in further increased susceptibility to diseases. Nutrient/dietary medications, such as antioxidants and certain lipids have suggested a promising route to reduce the age-related increase in COX activity and PGE(2) production that is associated with several disease states.

Probiotics improve bowel movements in hospitalized elderly patients — The proage study

“…Some studies in the elderly have found that probiotics could enhance immune response (13,30,32). Moreover, in a study of healthy elderly volunteers, it has been shown that those with the poorest immunological response had the best enhancement of immunity after probiotics intake.…”

“…A simple available way to measure chronic inflammation is by assessing the CRP level (32). Some studies in the elderly have found that probiotics could enhance immune response (13,30,32).…”

Suppression of intestinal inflammation and inflammation-driven colon cancer in mice by dietary sphingomyelin: importance of peroxisome proliferator-activated receptor γ expression

“…In macrophages, an increase in ceramide levels was associated with a higher Cox-2 expression [20] via NF-κB activation [18]. Exogenous ceramide mimicked these events in murine macrophages and it is thought that a ceramide-mediated suppression of PPAR-γ prevents suppression of NF-κB activity (see recent review [50]). Other studies suggest a key role of ceramide in the increased secretion of pro-inflammatory cytokines via NF-κB activation in adipose tissue-associated macrophages [18], and Cox-2, cPLA2 and 12-LOX in primary astrocytes [51].…”

Characterization of an arachidonic acid-deficient (Fads1 knockout) mouse model

“…As AA-derived eicosanoids play an important role in immune regulation ( 27,28 ), we next investigated the immunomodulatory effects associated with a defi ciency in AA-derived 2-series prostaglandins. For this purpose, we acid analysis also confi rmed that Fads1 null mice have negligible levels of AA ( ‫ف‬ 1 mol%) compared with heterozygous ( ‫ف‬ 14 mol%) and wild-type ( ‫ف‬ 15 mol%) mice ( Fig.…”