Should we die?
Ladies and gentleman, I must announce now your destiny. You are going to die. Do you want to die now? No? Sometimes later? Maybe? How about never? Perhaps. So it is and I must also inform you, this is a question we must answer soon.
Fighting the reaper had been the dream of many throughout our history as a civilisation; from emperors to popes to philosophers and to the countless common folks, we tried and tried again to escape this finality. Though, not until recently have we found a path potentially to defeating the reaper once and for all.
In this article, I will discuss two approaches we have come to realise in our recent discovery and development to further our cause of human longevity; clearing of senescent cells accumulation, and Stem cell treatment.
Senescent cells, telomeres and ageing process
No process in the natural world are perfect, including the replication and division process of your cell. With each replication, a certain section on each end of the chromosome is lost. As a protective mechanism against this process eroding away useful information in the DNA, each end of your chromosome have a bit of extra known as telomeres. The average length of telomeres in each chromosome is around 8,000 to 10,000 nucleotide in a newborn child.
This protective extra on each end, with the passage with time, wears out after around 50 cell division. At this threshold, the cell practically terminate all it’s function, and thus becomes what is known as a senescent cells. In another word, senescent cell may be think of as retired cells in ones body.
These retirees, however, are no good to your bodily function. They are often noisy and disturb other adjacent cell in its neighbourhood (or known as tissue) by emitting inflammatory agent. This disrupts the functionality of nearby cells , which triggers a further chain reaction as the affected cells begin producing its own inflammatory agent.
As human ages, our body accumulate senescent cells. Accumulation of senescent cell increase the risk of practically all age related pathologies, and are commonly associated as a indication of Aging itself. This process though, is seemingly reversible.
Affect of senescent cell accumulation is best mitigated by clearing them out of one’s body. The two most prominent ways discovered and developed in recent times are perturbing the function of Forkhead box protein O4, or through fasting induced autophagy.
The survival of senescent cell are dependent on the function of Forkhead box protein O4, thus by clinically introducing external factors perturbing the function of the protein, accumulation of senescent cells can be effectively reduced. Senescence-associated secretory phenotype (SASP) are currently the best candidate for this job, inducing neighbouring cells to repair the tissue and attracting inflammatory cell to eliminate senescent cells.
Autophagy are a cellular process essentially of recycling usable material in dysfunctional organ and reusing it as energy (glucose). Human Cell are generally triggered to undergo autophagy in environment where energy is scarce. When triggered, dysfunctional senescent component are removed and recycled into protein and glucose, effectively reducing the senescent build up.
Stem cells research
Stem cells are essentially undifferentiated cells within human body. Two types of stem cells are generally present: Adult (tissue specific) stem cells, and embryonic stem cells.
Lets begin with adult stem cells. Adult, or tissue specific stem cells are, as the name suggest, within each and every one of your tissue. When certain cell dies in the tissue for any reason, the tissue specific stem cell may be used to take its place. Tissue specific stem cells, though, are not pluripotent, meaning it does not have the ability to differentiate into different types of cells within ones body.
Embryonic stem cells, on the other hand, are pluripotent. They are most commonly found within infant, and as newly discovered, in the placenta. Embryonic stem cells are a potential gate way to extension of health span and longevity for its potential in differentiation into different cells within ones body.
Another type of stem cells are induced pluripotent stem cells. They are not a natural occurrence, however, but a genetically engineered tissue specific stem cells to regain its pluripotent attribute.
In regard to longevity, several implication of stem cells have been identified. It is believed that the injection of pluripotent stem cells (either type) into certain human organs may invigorate its function. Animal test had been performed on rodents where pluripotent stem cell is injected to its hypothalamus. The result is positive; the treated rodent displayed a higher ability in physiological function and seen observable extension in life span.
Further, as the basis of regenerative medicine, induced pluripotent stem cells can be relied on to differentiate into the tissue specific cells, then transport to the tissue in need of repair. The focus of current research of stem cell therapy is on this field, with the most prominent effort focused on cardiovascular tissue (regeneration and repair of heart cells in prevention of heart disease) and Endothelial Precursor Cells (Regeneration of blood vessel and formation of new ones).
In the recent decade, we had made several prominent discovery in regard of extension to human life span and health span. Senescent cell and stem cell research are the more established field amongst many others. One must then speculate; how far away are we indeed, from fighting off the reaper, for better or for worse.
