Why does skin age and how to deal with it?

The autumnal equinox has arrived, and the hot summer has finally passed. How is your skin after a summer? What do you think is the most important thing in skin care?

I think it is anti-aging and thus restoring youth. Many people may find this counterintuitive. Isn't anti-aging something that you need to consider when you reach a certain age? Do you need to do it at a young age? Today, let's talk about skin issues.

01Why do skin problems occur?

Why do we rarely hear about teenagers doing various forms of skin care? Just look at their plump collagen and firm skin and you will know that it is proof of youthful vitality.

Why do many people need to take care of their skin after they become adults? Because you will find that our skin begins to have some problems, such as decreased skin elasticity, changes in skin color and skin texture. If we do not take care of our skin, these problems will be further aggravated.

At this time, people often think: there must be some reason. Of course, skin experts have analyzed this series of reasons for us. Ultraviolet rays will continue to attack our skin, causing damage and melanin production, ubiquitous oxidative stress and inflammatory molecules will damage skin cells, and poor living habits will affect rhythm, etc.

But if you examine these factors carefully, you will find that they all point to one essence: cells are old. If the cells are young enough, these are not a problem, they can directly repair these problems or simply renew themselves. Because the cells are old and have insufficient repair capacity, they cannot cope with these problems, so we need all kinds of skin care to help us, whether it is to strengthen defense or promote regeneration.

Don’t think that aging is something surprising. If you look back at the cellular life signs such as telomeres, you will understand that aging actually starts very early, much earlier than we thought, but you didn’t notice it at first. Especially in the beginning, our skin’s repair ability will cover up these essences. However, as time goes by, various components in the cells are damaged more and more, and the repair ability is obviously unable to cope with it. Even the repair system itself is damaged, so skin problems arise.

So, what is the most fundamental thing about skin care? The answer actually points to root anti-aging.

02How to fight aging from the root?

How to fight aging from the root? In fact, this question is a difficult question that countless people have been asking since ancient times. Countless people in history have tried various methods to resist aging and achieve longevity, but all ended in failure.

It was not until the last century, with the extensive research of modern science, that we began to find some factors related to aging, a typical example of which is the sirtuin family (translated as "sirtuin" in Chinese).

There is a story behind the discovery of the Sirtuin family. We know that yeast is a common experimental material, and many biological experiments require yeast.

However, scientists have found that although they are all yeast, some yeasts have a particularly long lifespan, which has aroused the curiosity of scientists. What is the reason why some yeasts have a longer lifespan? We know that genes determine traits, so they studied the genes of yeast and found that the cause of all this is a gene called sirtuin, which is a deacetylase that is used to modify a variety of non-histone proteins. If this gene is manipulated, the lifespan of yeast can be significantly extended.

In this case, does this sirtuin have homologous genes in other organisms? So the researchers explored the genes of different species and found that this gene is widely distributed in different species, including 7 members, namely SIRT1-7. Although sirtuin is a NAD+-dependent deacetylase and deacylase, it plays many roles in cells, including DNA damage repair, cell metabolism, mitochondrial function, etc., which also means that sirtuin is a gene family with important regulatory capabilities for life and health.

03. Does the sirtuin family have a longevity function in other species?

So, does the sirtuin family play the same longevity function in other species as in yeast? So the researchers explored the anti-aging and longevity effects of the sirtuin family and found that this effect can be achieved in multiple species.

Taking mice, the most common mammalian experimental model, as an example, researchers have found that simply overexpressing a previously neglected gene, sirt6, can significantly extend the lifespan of mice, increasing their lifespan by 30% [1]

Moreover, after overexpression of sirt6, the mice showed an overall younger trend. Moreover, the blood of the mice was investigated, and the red blood cell (RBC) count, hematocrit (Hct), hemoglobin (Hb), and serum albumin concentration in the mice were successfully saved. Some indicators were even better than those of young mice, which can be called "rejuvenation" to some extent.

As for Sirt1 and 2, which have been studied more, they have been proven to have good anti-aging effects in multiple studies.

04Study on the sirtuin family

Nowadays, the research on sirtuin family is very popular, which is actually very easy to understand. Who is most concerned about the progress in the field of anti-aging? The skin care field is undoubtedly the most important. After all, anti-aging is a major demand in the skin care field. If they can participate in the research of anti-aging, then they may be able to plan ahead and introduce it into the product line to obtain huge application space.

Sirt3 is a key regulator in keratinocyte formation and skin barrier maintenance, and can participate in keratinocyte differentiation by reducing the level of oxidative stress during the differentiation process [2].

For example, an article in the Nature portfolio introduced the research on SIRT2 [3].

This is a protein located in the cytoskeleton, which can help cells avoid the effects of aging by maintaining the integrity and function of the cell structure, but with aging, the activity of sirt2 begins to decline. Studies on other members of the sirtuin family have also found similar effects, of course, because different sirtuins have different locations and functions.

This has even been verified in humans, with a typical example being the study of long-lived people. Bama in Guangxi is a world-renowned longevity region, where the proportion of centenarians is much higher than the national level. Some people have studied the sirtuins in the local long-lived population and found that their sirtuin content is significantly higher and more active, which may explain to some extent why there are more centenarians in the region. In terms of the polymorphism of sirt6, there is also a clear difference between people in longevity areas and non-longevity areas, indicating that the sirt family has a greater genetic effect [4].

It can be said that today, the ability of the sirtuin family to resist aging and prolong life has been confirmed by many scientific research results.

In fact, the essence of skin care is to rejuvenate and regenerate skin cells. Those other skin damage factors and protection methods that we often mention are essentially an impact on skin aging. Only by comprehensively improving the aging condition of the skin can we achieve true skin care as a whole.

1. Roichman A, et al. Restoration of energy homeostasis by SIRT6 extends healthy lifespan. Nat Commun. 2021 May 28;12(1):3208.

2. Bause, Alexandra S., Mary S. Matsui, and Marcia C. Haigis. "The protein deacetylase SIRT3 prevents oxidative stress-induced keratinocyte differentiation." Journal of Biological Chemistry 288.51 (2013): 36484-36491.

3. https://www.nature.com/articles/d42473-021-00419-6

4. Liang Guiyun. Study on the correlation between SIRT6, PON1, HSP70 gene polymorphism and longevity in Bama, Guangxi[D]. Guangxi Medical University, 2012.