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Cross-linking theory of aging

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Structural changes of proteins due to molecular Cross-linking Cellinsight Everything about human ageing and related diseases Understanding Cross-linking theory The cross-linking theory of aging was proposed in 1942 by Johan Bjorksten. According to this theory Collagen and other proteins undergoing structural changes due to molecular cross linkage (collagen is an important body proteins comprising 30℅ of body proteins) . In the presence of oxygen glucose molecules binding to to proteins and this cross-linked proteins causing damage to cells and tissues resulting in aging. This theory is also called as glycosylation theory of aging.  # Wrinkle and skin changes The cross-linked skin protein collagen  is responsible for wrinkles and skin changes during aging # Tendon stiffening An increased cross-linked collagen is the reason behind tendon stiffening, tendons are connective tissues which connect muscles to bones. a stiff tendon can pass more mechanical energy from ...

Animals who defeated ageing.

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Cellinsight Everything about human ageing and related diseases Immortal animals Nothing is forever in this world, death is certain, one day it will visit us. But there are some creatures that never die by natural aging process. Human cells are capable of dividing only 50 times, later the cells entered the senescence stage, and this is the exact reason for aging. Any animal which is not experiencing senescence can defeat ageing, today I am going to tell about such types of animals and how they live without the fear of ageing 1. Jelly fish (Turritopsis dohrnii)  Immortal jellyfish (Image credit goes to Wikimedia )  Jelly fishes are sea animals, included in the phylum coelenterata (cnideria). Turritopsis dohrnii is a species of jellyfish which is known as immortal jellyfish. Jellyfish reproduce both sexually and asexually.The life cycle consisted of three main stages, planulae,polyps and medusae. fertilized egg give birth to planula. The  Planula is the larval stage...

The Hallmarks of aging

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What are The 9 hallmarks of Aging ?  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 expl...

Telomere theory of aging

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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 cancecells and germ cells ,these cells are devoid of aging and they are immortal.The telomere theory of aging got more popularity when three geneticists, Elis...

The free radical theory of aging

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style="text-align: left;"> 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. Cell struc...