The interactions between the nervous and immune systems have been associated with psychosocial stress, peripheral inflammation, and chronic diseases (Liezmann et al., 2012; Peters et al., 2012). The concept of “inflammaging” refers to the premature aging with a pro-inflammatory condition and chronic inflammation (Liezmann et al., 2012). One of the most important organs involved in the neuroendocrine-immune interactions and stress responses is the spleen that modulates the immune reactions.
In acute peripheral inflammation, the activation of the stress axis and immune adaptation is critical to reach a balance, such as the activation of the sympathetic axis. In addition, the hypothalamus-pituitary-adrenal axis also plays a crucial role (Peters et al., 2012). Higher levels of neurotrophin and neuropeptide can be induced. The plasticity within the neuroendocrine-immune interactions enables the continuous adjustment to meet the challenges from the environment and from the inside (Liezmann et al., 2012).
However, the chronic activation of the stress-axis may alter this plasticity, leading to maladaptation and chronic inflammations. Thus inflammaging can be caused and enhanced by chronic stress conditions (Liezmann et al., 2012). Chronic stress responses may influence many organs such as the skin, and cause a variety of skin disorders including allergic inflammation, skin cancer, and psoriasis (Peters et al., 2012). More studies in psychoneuroimmunology are still needed to elucidate the underlying mechanisms of the acute and chronic stress responses to find better treatment for chronic inflammatory diseases.
Liezmann C, Stock D, Peters EM. Stress induced neuroendocrine-immune plasticity: A role for the spleen in peripheral inflammatory disease and inflammaging? Dermatoendocrinol. 2012 Jul 1;4(3):271-9. doi: 10.4161/derm.22023.
Peters EM, Liezmann C, Klapp BF, Kruse J. The neuroimmune connection interferes with tissue regeneration and chronic inflammatory disease in the skin. Ann N Y Acad Sci. 2012 Jul;1262:118-26. doi: 10.1111/j.1749-6632.2012.06647.x.