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Human ageing

The Hallmarks of aging

Aging- a Symbolic presentation What are The 9 hallmarks of Aging? According to the scientific world there are 9 reasons behind Aging, they are generally known as 9 Hallmarks of Aging. They are Genomic instability, Telomeres Attrition, Epigenetic Alteration, Loss of Proteostasis Deregulated Nutrient Sensing, Mitochondrial Dysfunction, Cellular senescence, Stem cells Exhaustion and Altered inter cellular Communications. genomic instability Genome is the genetical codes present in organisms. In other words genome is the complete set of DNA present in a cell. Every cell has  copy of the DNA. Genomic instability is the result of high frequency mutations ( sudden changes ) Because of  these mutations chromosome May rearranged, sometime the sequence of nucleic acids  or even the chromosome number May changed,( the chromosome number of human is 23 pairs, or 46 ).  Telomeres attrition Telomeres are the tail ends of chromosomes, which act as protective caps. I already explained about telome

Telomere theory of aging

Telomere theory of aging
Telomere theory of aging was proposed by a Russian scientist A.M.Olovnikov in the year 1971.In the year 1961,an american scientist L.Hayflick  discovered that cultured human cells can only divide up to 50 times.On the basis of this discovery and it's data A.M olovnikov studied more and proposed the telomere theory of aging. According to the theory,when the telomeres (tail end of  chromosome) become too short the cells lose their ability to divide,gradually it lose its efficiency and become aged.After each and every cell division telomeres are unable to be fully copied,therefore they become shorter and shorter.The telomere theory was fully confirmed when an enzyme called telomerase was discovered in 1984,telomerase can maintain the length of telomeres in cancer cells and germ cells,these cells are devoid of aging and they are immortal.The telomere theory of aging got more popularity when three geneticists,Elisabeth Blackburn,Carol Greider and Jack Szostak got Nobel prize in the year 2009 for Physiology or medicine.Their work was based on telomers and telomerase enzyme, Elizabeth Black burn discovered that telomers have a peculiar DNA,she and Jack Szostak proved that the DNA present in telomers prevent chromosome from being brocken drown when cell divides in the year 1982,Elizabeth Black burn and Carol Greider discovered the enzyme telomerase in 1984.

Location of telomere
Location of telomere

TELOMERE

 Telomeres are the tail ends of chromosomes,working as protective cap.They consist of same sequence of bases.Generally there are four bases adinine,guanine,thymine and cytosine in human being the sequence is TTAGGG(thymine-thymine-adinine-guanine-guanine-guanine),this sequence repeated over and over.This sequence is repeated approximately 2500-3000 times and can reach up to 11000-15000 base pairs.Base sequence differs in different animals,for examble In the case of Bombix mori(insect) the base sequence is TTAGG,ascaris(round worm) the sequence is TTAGGC,Plasmodium(Protozoa) the sequence is TTAGGG(T/C), Paramesium(Protozoa)the base sequence is TTGGG(T/G) and so on.In human telomeres are consisted of TTAGGG sequence of bases,here I am talking about one strand only,what about the other strand?,as we know thymine (T) always pairs with adenine(A),and guanine(G) with cytosine (C) so if TTAGGG sequence is on one strand the other strand sequence will be AATCCC,so one section is made up of six base pairs.
It is noted that the length of telomer in WBC (white blood cells) of newborn babies is 8000 base pairs approx ,but in adult the data is 3000 base pairs and in elderly people it will be 1500.Each time cell divide telomere loses 30 to 200 base pairs.Telomere do not shorten in heart muscles cells,because it do not divide continually .

Cell division

All the living organisms that start their life with a single cell.For growth and reproduction, the cell divion is necessary,each parent cell is divides in to two and later, these cells will divide again and this process will continue. There are two types of cell divisions occurs in our body, mitosis and meiosis.The mitosis is the common type which is the process of making new cells in our body,the other one meiosis which makes egg cells and sperm cells.The mitosis cell division is a very critical process, during this the parent cell split in to two identical daughter cells and this process is controlled by a number of genes,eventhough he length of telomeres decreased after each cell division.The other one the meiosis cell division reduces chromasome number by half( 46 to 23),unlike mitosis the end product of meiosis is four daughter cells with 23 chromosomes) these daughter cells should be sperm cells or egg cells.

Medicine available to increase life span
many medicine are available at online for altering telomere's length. For example, TA65®.  This is a patented natural herbal product.The company   Claims "this compound can help to maintain the length of  telomers by activating telomerase enzyme.It can  slow down and possibly,reverse aging". Another one human telomerase reverse transcriptase(hTERT) which is used to diminish telomer's length,you may wonder why should one diminishes telomer's length?, well this is an effective medicicine fort cancer,especially for tumors,you know cancer cells are able to produce excess telomerase so the length of telomere never reduced,they are immortal.hTERT used to diminish telomer's length, and therefore the cells become inactive. This type of medicines manufactured a number of companies in different names and different forms.
Conclusion
Telomere theory of aging is a most popular theory of aging.It is proved that after each and every cell division the length of telomere decreases,it is also noted that telomere shortening is different for every one,when we try to measure,for some people you can see the difference in 3 years and some others it can notice in 5 years depend on health status,stress reduction and healthy habits can help to slow the telomere shortening. 
Special info
our blog is again selected for top 60 aging blog, by feedspot.com,again my sincere thanks to Mr. Anuj Agarwal and his team.
             Cellinsight.online

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