The macrophage respiratory burst

The cytotoxic action of macrophages is due to production of radicals, including halogen, nitric oxide and oxygen radicals. This means that infection can lead to a considerable increase in the total radical burden in the body. As discussed in section 8.5.1, this may be an important factor in the protein—energy deficiency disease kwashiorkor.

Stimulation of macrophages leads to a considerable increase in the consumption of glucose (the respiratory burst), which is metabolized by the pentose phosphate pathway (section 5.4.2), leading to increased production of NADPH. The respiratory burst oxidase (NADPH oxidase) is a flavoprotein that transfers electrons from NADPH onto cytochrome b558, which then reduces oxygen to superoxide. The reaction is:

The respiratory burst oxidase is a transmembrane multienzyme complex that is activated in response to:

  • complement fragment C5a which arises from the antibody—antigen reaction;
  • peptides containing N-formyl-Met-Leu-Phe, which may be bacterial or arise from the mitochondria of damaged tissue;
  • cytokines and other signalling molecules released in response to infection, including platelet-activating factor, leukotrienes and interleukins.
Supplements For Diabetics

Supplements For Diabetics

All you need is a proper diet of fresh fruits and vegetables and get plenty of exercise and you'll be fine. Ever heard those words from your doctor? If that's all heshe recommends then you're missing out an important ingredient for health that he's not telling you. Fact is that you can adhere to the strictest diet, watch everything you eat and get the exercise of amarathon runner and still come down with diabetic complications. Diet, exercise and standard drug treatments simply aren't enough to help keep your diabetes under control.

Get My Free Ebook

Post a comment