QS Study

Cortisol is a steroid hormone that is thought to be taken up in a target cell by simple diffusion. It is often called the “stress hormone” because of its correlation to the stress reaction, however, it is much more than just a hormone released during stress. Cortisol is a powerful anti-inflammatory, even when secreted at normal levels.

Anti-inflammatory effect

The main basis of anti-inflammatory effect:

Nuclear factor – kb, (NFkB) is a transcription factor which normally exists in the cytoplasm of cells bound to IkBk which renders into inactive stimuli such as Cytokines, viruses, and oxidants separate NFkB, from IkBk, which is then degraded. NFk-B moves to the nucleus, where it binds to the DNA of the genes for numerous inflammatory mediators, resulting in their increased production and secretion.

Cortisol inhibits the activation of NF-kB by increasing the production of IkBk and this is probably the main basis of its inflammatory action.

  • Suppresses lymphoid tissue systemically, therefore, decrease in T cell and antibody production thereby decreasing immunity.
  • Decrease immunity could be fatal in diseases such as tuberculosis,
  • Decrease immunity effect of cortisol is useful during transplant operations in reducing organ rejection.
  • Reduces fever,
  • Suppresses allergic reactions.

Fig: Pro- and Anti-Inflammatory Effects of Stress in the Brain

Prevention of the development of inflammation:

Cortisol prevents the development of inflammation by the following effect:

(a) Cortisol stabilizes the lysosomal membrane. Therefore most of the proteolytic enzymes that are released by damaged cells to raise inflammation which is mainly stored in the lysosome. So, cortisol decrease quantity.

(b) Cortisol decreases the permeability of capillaries.

(c) Cortisol decreases both migrations of WBC into the inflamed area and phagocytosis of the damaged cells

Cortisol diminishes the conc. of prostaglandin and leukotriene.

(d) Cortisol suppresses the immune system, especially T – lymphocytes.

(e) Cortical reduces/lowers fever because of reducing the secretion of IL-1.

Resolution of inflammation:

Cortisol causes resolution of inflammation by mobilization of amino acid and fatty acid to the Inflamed area, we them for gluconeogenesis for repairing the damaged tissue. It acts rapidly to get rid of and avert redness and swelling of almost all tissues. These anti-inflammatory actions keep mosquito bites from flaring into giant lumps, bronchial tubes and eyes from swelling shut from allergens, and mild scratches from looking like you have just had a close call with a mountain lion.