Skip to main content

Human ageing

Effects of enzymes on aging and related diseases .

Effects of enzymes on aging and related diseases  Enzymes How enzyme catalyze a chemical reaction Enzymes are biological catalysts , catalysts are those substances which can alter the speed of chemical reactions.There are positive and negative catalysts, positive catalysts speed up chemical reactions where as negative catalysts decreases the rate of chemical reactions.Enzymes are positive catalysts, which accelerate chemical reactions in our body.Enzymes are basically proteins ,made up of long chains of amino acids .Enzymes are discovered in 1897 by a German biochemist Eduard Buchner , he got Nobel prize in chemistry in 1907 for his discovery of cell-free fermentation . He showed that an enzyme named zymase extracted from yeast cells can break up sugar into alcohol and carbon dioxide.There are about 40,000 different enzymes present in our body ( these number may increase because every day new enzymes are discovering )each enzyme catalyze a different chemical r

The free radical theory of aging


The free radical theory of aging

Dr.Denham Herman a scientific researcher who proposed the 'free radical theory of aging' in the year 1956.according to this theory the process of aging is due to oxidative damage of cell organelles and other cytoplasmic contents by free radicals. intially it was assumed that the free radicals such as ROS(reactive oxygen species) produced during normal respiratory process.The free radical theory got more attention when researchers studied the cause of cancer ,Alzheimer disease,and heart diseases .This theory realises that old age is just another disease,our old age is starting when mitochondrial DNA (mtDNA) get damaged by free radicals.1970s many scientist involved in Reserch related to this theory and in 1980 J.Miquel clearly explained the mitochondrial involvement in the production of free radicals,the theory is known as mitochondrial theory of free radicals.
The free radical theory of aging
Cell structure
                   Animal cell,inrenal view (mitochondria distributed incytoplasm)

Mitochondria(mitochondrion-singular)

Mitochondria are tiny cellular organelles which are freely distributed in cytoplasm,they are covered with two membranes.The outer membrane is a double phospholipid layer,it covers and protects the inner part of the organelle and the inner one folded many times and forms structures called cristae,the fluid filled inner space of the organelle is called matrix.mitochondria has its own DNA(mtDNA)and ribosomes. mitochondria are often called as power houses of cell,they produce energy and stored in it.The energy that released from metabolic activities are using to convert ADP(adenosine diphosphate)to ATP(adenosine triphospate),when energy utilised ATP will change to ADP.More mitochondria are present in such cells which need more energy,for example muscle cells contain more mitochondria because it needed more energy for muscular activities,the Neuron has the least numer of mitochondria because it's function is to conduct electric impulses to and fro from central nervous system and deferent parts of the body,it need not much energy to work,and RBC( red blood corpacells)has no mitochondria because it need no extra energy to perform it's function,it work as oxygen carriers,the haemoglobin present in the RBC capable of doing the work.Most of the metabolic process is done inside mitochondria with the help of oxygen,this process is also called cellular respiration.
The free radical theory of aging
internal view


Free radicals

Free radicals are atoms or molecules with one unpared electron,in other words they are charged atoms or molecules.They are unstable and highly reactive,it pull out an electron from adjacent atoms or molecule to attain stability,the atom or molecule where the free radical pulled out electron became unstable and act as free free radical it will attack another and this process will continue,finally the whole cell may damage this process is called chain reaction.Initially ROS (reactive oxygen species)is termed as free radicals but later RNS(reactive nitrogen species) radicals are also found involving in oxidatative damage to cells and tissues.Both species consist of a number of free radicals and non radicals,non radicals also make damage to our body,some of the radicals and non radicals are giving below,
Super oxide....................O2*-
Pyroxyl...........................ROO* (general code),eg;(HOO*)
Hydrogen peroxide.........H2O2
Ozone................................O3
Hypoclorous acid............... Hocl
Nitric oxide........................NO*(RNS)
Nitrosyl anion......................NO-
Nitrosil cation......................NO+
Nytryl chloride ....................NO2cl
Nitrous acid.....................HNO2

Peroxynitric acid..................ONOOH

The antioxidants

Antioxidants are substances that are able to neutralise free radicals by donating an electron,eg ; vitaminC, vitaminE,beta-carotene,etc.
Age related mascular degeneration can be treated by vitaminC,beta-carotene, and zinc to some extent,complete relief is not possible.study shows that skin cancer patients get significant reduction in cancer when treated with selinium.Anti oxident rich food such as fruits and vegetables can diminish oxidative stress and increase life span.once Dr.Denham Herman said 'accept the fact that you are not going to live fore ever but there is possibility if you work at it,you might make 100'. Herman used to eat vitamin rich diets and he died at the age of 98.

Oxidative stress

Oxidative stress is an imbalence of free radicals and antioxidants in the body,body produced a small amount of antioxidants the rest is absorbed from food,vegetables and fruits are good sources of antioxidants and also the regular excersice is good for avoiding oxidative stress,but it increases the formation of free radical the result is temperaly oxidative stress,however the free radical formed in muscles stimulate the production of antioxidants in the tissue.

Challenges

√ our immune system producing free radicals,WBC producing free radicals that used to kill micro organisms that enter in our body.
√ scientist considered the free radical theory as one of many reasons of aging.
√ scientists compared the life span of parrots with same sized birds the quails,the ROS production in heart,liver,erythrocytes, muscle etc are very similar in both birds species,but parrots live 5_7 times more than the quails,feeding habit of both birds are different,parrots eat fruits,seeds etc,while quails eat grains insects etc 80% of its food is carbohydrate. If you  give same meals for both birds,the result is same,the parrots live longer,this experiment cannot explain on the basis of oxidative stress theory

Conclusion

The free radical theory failed in a number of scientific observation and even some sources said the theory is flavoured.however the cause of many degenerative diseases such as cancer,old age heart diseases, Alzheimer,atherosclerosis, and other chronic conditions found on the basis of this theory.Diet restriction can increase life span,this is scientifically proved and nobody question about it.There are many limitation to conduct experiment on this theory,the free radicals formed in our body will disappear within fraction of seconds,it will react with other molecules or atoms.Only way is to check the oxidative damage of DNA,proteins, lipids, connective tissues etc,there are  various testing tool kits available in the market for this purpose.
Special information
l started this blog recently, hardly one and a half month ago,today I am happy to infom all of my readers that this blog is selected for top Feedspot top 20 biotech.blog and they provided visitors to my blog, my sincere thanks to feedspot.com and it's founder Mr.Anuj agarwal.

                         Cellinsight.online

Comments

Popular posts from this blog

HOW THE CORONA VIRUS INFECT HUMAN?

Covid19 Use mask for protection 

Role of protein on ageing

Protein structure  Role of protein on aging  Protein which controls the length of telomere are telomerase and a protein complex known as shelterin.a new study by Scripps Reserch Institute (TSRI) discovered a new protein named as TZAP (telomeric zinc associated protein)which decrease the length of telomeres by trimming,telomere is the clock of a biological cell,if it's length is too short the cell cannot multiply,a human cell can divide maximum 50 times,if it increase more, our life span may increase considerably. Certain proteins undergo oxidisation which are known to be associated with ageing and some age related diseases,when people turn about 80 approximately half of the bady proteins are damaged due to oxidation,the oxidation occurs because of random chemical degradation,that are associated with convention of food particles to enregy( metabolism) . Protein's misfoldings are another reason for ageing,when native proteins are synthesised in our cells,which i

Why we are getting old?

Why we are getting old? The answer is simple,the 'errors'.The errors that happening during cell multiplication and by the influences of external factors. Somany  changes happens in DNA every year,most important one is the shortening of telomeres. A telomere is the tail end of chromosomes.  The free radical theory of -ageing,  which devolved in1950 says that  the reactive oxygen  species(ROS)   produced during mitochondrial functions react with their DNA (mtDNA)  and other cell organelles, makes sever damage and declined mitochondrial functions that leads us to aging. ROS is produced when mitochondria make energy from food particles,when we eat more the mitochondria produce more energy and more ROS also evolved as by product. So having a comparatively limited amount of diet and  anti oxidant rich food,such as green vegetables fruits etc can increase life span.  In the year 1961 an American scientist L.Hayflick discovered that human cells have limited capacity to divide