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Differences between “prime aging” and “anti-aging”


Functions of longevity genes (Telomere and Sirtuins)

Hello everyone. In the fifth article, I would like to talk about prime aging and longevity genes.
Telomere is one kind of genes that is associated with longevity. We first need to have knowledge about how human bodies are maintained, as a premise to understand what telomere is. A human body is made up of about 37 trillion cells on average through the whole life time. Among them, about 1% of these cells, approximately 200 billion cells die, and are replaced with new cells every day. Bodies of many living things, including human beings, are maintained by this process. Chromosomes play a key role in creating cells. They exist in the nucleus of cells, storing genetic information that are indispensable for cell proliferation. They are as if a blueprint for construction since cells are created based on this information. However, cell proliferation is discontinued at a certain point of the lifetime, and when it happens may be different according individual cells. Telomere is deeply involved in how many times cells are divided.

It has been found that telomeres stick to both ends of chromosomes, which are like plastic covers that bundle shoelaces. Telomere DNA becomes shorter little by little at each cell division. Then subsequently cells become unable to be divided any more, and finally die. This can be called “aging of the cell.” Telomeres, are also called as if” coupon tickets for a lifetime”, which are deeply associated with development of serious diseases such as cancer, arteriosclerosis, and myocardial infarction. I would like to cite an example; when cells are damaged by ultraviolet rays which sometimes trigger skin cancer, or by tobacco which may cause cancer, cell divisions become active in order to replace damaged cells with new ones. As a result, telomeres in these cells become shorter in less time. Cells become unstable once they lose telomeres, and may be connected to other chromosomes. Alcoholic hepatitis progresses to liver cirrhosis, and eventually to liver cancer in this process. Telomeres in patients with cancer or other diseases tend to be shorter. However, people whose telomeres are shorter don’t necessarily suffer from cancer. Additionally, it has been clarified that our bodies also have enzyme called telomerase, however, unfortunately no reliable way to activate telomeres to lengthen telomeres have been found. Although telomere is attracting a great attention as an indicator to measure aging status in anti-aging medicine societies, further studies and researches are required to apply this mechanism in clinical practices.

I would like to talk about another kind of genes that is associated with longevity. It is called sirtuin. A cell has an organ called ribosome, which produces protein. Sirtuin regulates information of genes that produce ribosome. Sertuin is called “longevity gene”, and it is considered to reduce oxidative stress on mitochondria that produces energy for cells, to suppress inflammation, to promote insulin secretion from β cells at the pancreas, and to improve metabolism of sugars and lipids in the liver. Along with these findings, it has been also shown that these genes are usually dormant. It is suggested that sirtuin is activated and ameliorate aging, when the body is in dietary- restricted status (energy intake is limited to 70% of the required amount), or light physical exercises, like jogging, is performed. Furthermore, sirtuin is considered to be negatively associated with accumulation of visceral fat. Therefore, it is expected to play a role as an indicator of metabolic syndrome. NMN (nicotinamide mono nucleotide), which activate sirtuin, have anti-inflammatory and anti-apoptosis activities, as well as are also deeply involved in metabolism of NAD+ (nicotinamide adenine self-nucleotide). NAD+ is deeply related to aging. Decreased NAD+ level induces troubles in deacethylation activity of sirtuin, and also affects the downstream reactions, including permeability and oxidative stress response of mitochondria. This sequence of abnormalities results in various dysfunctions of organs, including alcoholic liver disorder, acute renal failure, retinal degeneration and corneal disorder, Alzheimer’s disease, disorders in neuroprotection and cognitive function, intracerebral hemorrhage, vascular dysfunction, heart failure and myocarditis, ischemic reperfusion disorder, obesity, and diabetes. NMN has been studied in clinical trials as an intermediary metabolite in the metabolic pathway of NAD+. This substance is expected to slow down the aging process by strengthening the synthetic metabolism of NAD+ (nicotin amidadenin self-nucleotide), which is increasingly consumed due to aging.

We conduct researches on genes related to aging in the laboratory of our hospital. We would like to develop a technology to evaluate the biological age of patients, and to objectively measure effects of anti-aging supplements including BioBran.


Midori Meshitsuka M.D.

Midori Meshitsuka M.D.
M Regenerative Clinic Director

2008 Graduated from Peking University Health Science Center (China)
2009 Obtained Chinese medical license
2014 Obtained Japanese medical license
2019 M Regenerative Clinic Director
Dr. Midori completed her internship at Harvard medical school Massachusetts General Hospital and Peking University Third Hospital. She then worked at the University of Tokyo Hospital, Tokyo Women’s medical University. In 2019 she joined her family practice, established M Regenerative Clinic as Director.

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