Impact of oxidative stress on Cystic Fibrosis

Oxidative stress and the importance of antioxidant intake in Cystic Fibrosis

17 March 2021

Free radicals

Free radicals are particularly reactive molecules. They are constantly formed in our body as a waste product of natural metabolic processes that use oxygen (O2) as fuel to produce energy (oxidation). They are also called "Reactive Oxygen Species" (ROS). Superoxide anion (O • 2 - ) and hydroxyl radical (• OH) are among the most common ROS. 

Oxidative stress is a pathological condition that occurs when an imbalance is produced in a living organism between the production and elimination of oxidizing chemical species.

In an oxidative stress state, there is an abnormally high amount of free radicals, which exert a harmful action on the cells and tissues of our body.

One of the physiological roles of free radicals is to promote oxidation which eliminates pathogens and generates energy. When there is an excess, however, they produce oxidation that can damage cell membranes and cause cell death. Free radicals are highly toxic in nature and, if accumulated in excess, can damage macromolecules such as proteins, lipids, mitochondrial and nuclear DNA.

Free radicals are implicated in a large number of human diseases, such as atherosclerosis, Alzheimer's, carcinogenesis, cataracts, diabetes mellitus, rheumatoid arthritis, lung and kidney diseases, and inflammation.

Antioxidants to counteract the action of free radicals

Free radicals are constantly produced in a normal cell or tissue, but they are inactivated by metabolic processes. Antioxidant substances restore the chemical balance in free radicals thanks to the ability to provide them with the electrons they lack. The human body naturally defends itself from free radicals by producing endogenous antioxidants such as superoxide dismutase, catalase and glutathione.

Oxidative stress and cystic fibrosis

Cystic Fibrosis is a pathology characterized by a vicious circle that feeds itself with inflammation and infection. Due to chronic infections, there is an accumulation of free radicals, which in high concentrations fuel inflammation, in turn perpetrating this vicious circle.

The infection activates the immune system and first of all the neutrophils, which act by releasing ROS to counteract pathogens. ROS are not disposed of since CF subjects do not have sufficient antioxidant resources to counteract excess radicals and oxidative damage.

In conclusion, patients with Cystic Fibrosis experience both an excessive production of free radicals linked to the inflammatory and infectious situation that afflicts them and a chronic deficit of antioxidant defenses.

A strategic role is therefore the intake of antioxidants with the diet. In fact, there are many natural compounds with strong antioxidant activities present in our diet, for example polyphenols or flavonoids, anthocyanin, vitamins (especially A, E, C) and elements such as selenium or zinc. Unfortunately, the well-known difficulties of a patient with Cystic Fibrosis in the absorption of vitamins A, D, E, K and antioxidants make a sustained integration to the diet necessary.

It is important that the diet of CF subjects is adequately supported with antioxidant substances as well as vitamins and Omega 3 fatty acids.

The synergistic action of these substances can promote the reduction of oxidative stress and counteract chronic inflammation.



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