Скачать или смотреть What are free radicals? How free radicals affects our health? Free radical damage

What is a free radical? A free radical is a molecule or molecular fragment that contains one or more unpaired electrons in its outer orbital. Oxidation reactions ensure that molecular oxygen is completely reduced to water. However, the products of partial reduction of oxygen become free radicals. They are highly reactive and are also called reactive oxygen species or ROS.

Characteristics of ROS of free radicals are,
1 Extreme reactivity.
2 Short life span.
3 Generation of new free radicals by chain reaction.
4 Damage to various tissues.

When free radicals attack proteins, they cause oxidation of sulfhydryl groups & modification of certain amino acids. Free radicals may damage proteins by fragmentation, cross-linking & aggregation, forming malformed proteins that can be detrimental for wellbeing of the cells and tissues.

When free radicals attack carbohydrates, it causes oxidation of monosaccharides (e.g. glucose) which can produce H2O2 & oxoaldehyde are in turn free radicals that set the chain reaction.
Free radicals may cause DNA strand breaks and fragmentation which may lead to mutant cells and cancerous cells.

Chronic inflammatory diseases such as rheumatoid arthritis are self-perpetuated by the free radicals released by neutrophils. Free-radical induced tissue damage appears to be involved in pathogenesis of chronic ulcerative colitis, chronic glomerulonephritis,

Cardiovascular diseases: Free radicals oxidize the LDL in our body. These oxidized LDL promote atherosclerosis & can cause cardiovascular or heart diseases.

Free radicals can damage DNA & cause mutagenicity and cytotoxicity & play a key role in carcinogenesis.

Respiratory diseases: Our lungs are directly exposed to oxygen over a long period. Hence, there is higher risk of free radical damage. Free radicals are also responsible for adult respiratory distress syndrome (ARDS), pulmonary edema, bronchitis or asthma.

Diabetes: When the free radical accumulation around pancreas leads to destruction of islets of pancreas which can lead to Diabetes, especially type 1 diabetes.

Free radicals also contribute to cataract formation. Free radicals reduce sperm motility and lead to DNA fragmentation thus leading to male infertility.

Free radicals play a pivotal role in the degenerative brain disorders such as Parkinsonism, Alzheimer's, dementia, and multiple sclerosis. Cumulative effects of free radical injury cause gradual deterioration in aging process.

Free radicals are so scary. They cause serious harm when left unchecked. We are at increased risk of free radical damages due to.
1. Air pollution.
2. Water pollution.
3. Increased radiation.
4. Increased use of pesticides and chemical fertilizers
5. Ultra processed foods with preservatives, colors and flavors added.
6. Increased stress levels.
7. Decreased activity levels.

However, we are not defenseless in our fight with free radicals. We have our allies in this fight called antioxidants. We will talk more about antioxidants in our next video.