Hair loss is one of the health problems faced by middle-aged and elderly people around the world, and in recent years, they have gradually become younger. With the deepening of research on healthy functional microorganisms, the problem of probiotics in repairing hair loss has become a new hot spot in scientific research and market application, but the mechanism of action of probiotics in repairing hair loss is not clear.
Therefore, this study explored the probiotics that can repair hair damage through multi-omics combination, and first analyzed the relationship between scalp microecology and hair loss by analyzing the composition of scalp microbial community in patients with hair loss and normal population.
1. Hair loss
Hair loss is one of the health problems faced by middle-aged and elderly people around the world, and it has become the "top priority" for many people, and it has gradually tended to be younger in recent years. Types of hair loss are divided into cicatricial alopecia and non-cicatricial alopecia, with cicatricial alopecia being when normal hair follicles are replaced by connective tissue and hair follicles no longer grow, resulting in permanent baldness.
Non-cicatricial alopecia is a reversible type of hair loss, which can regrow after treatment, mainly including androgenetic alopecia, telogen effluvium, alopecia areata, etc.
Among them, AGA is the most common, mainly caused by excessive androgen secretion in the scalp or oversensitivity to androgens. The main mechanism is that the 5OT-reductase enzyme in the hair follicle converts the free testosterone in the body into more active bi-gas testosterone, resulting in high levels of androgens in the scalp.
High levels of androgens can cause hair follicles to become miniaturized, and hair follicles gradually shrink until they fall out. Alopecia is characterized by miniaturization of the hair follicles on the forehead and top of the scalp, a gradual decrease in the density of damaged hair follicles, and a clinical manifestation of baldness.
Although hair loss has no direct impact on people's life safety, due to the long course of the disease, patients will have symptoms such as psychological anxiety and depression, which seriously affects the quality of life and physical and mental health of patients. At present, the main ways to treat hair loss are drug treatment and hair transplantation, but the side effects of drugs and the high cost of surgery have caused people trouble.
Long-term use of such drugs can lead to allergic reactions such as rashes, itchy skin, and even defects such as decreased libido. It does not meet people's needs in terms of efficacy, practicability and safety, resulting in most patients giving up treatment. Therefore, it is urgent to find a healthy and safe treatment to solve the problem of hair loss.
1. Hair Biology
The growth cycle of hair mainly includes anagen, catagen, and telogen phases. Hair follicles themselves can produce a variety of growth factors, cytokines, neuropeptides and hormones to regulate and maintain their own growth cycle. During the anagen phase, hair follicles enlarge and increase in number, and new hairs continue to grow.
When the activity of hair follicle cells gradually decreases, the anagen phase also slowly ends, entering the telogen phase, and a short anagen phase or a long telogen phase may lead to hair loss. At the lower end of the hair follicle, the hair matrix is made up of epithelial cells, which are encased by the dermal sheath and dermal hair papillae, and enter different differentiation processes to form the outer hair root sheath, the inner hair root sheath and the hair shaft.
DPCs stimulate peripheral vascular circulation around hair follicles, promote the growth of hair papilla cells and the formation of hair follicles, and regulate and maintain the normal growth cycle of hair follicles by secreting insulin-like growth factor and vascular endothelial growth factor.
2. Factors of hair loss
The main causes of hair loss include: genetic factors, drug factors, mental factors and scalp ecological environment. Hereditary alopecia is mainly closely related to the genetic mutation of patients, which leads to this genetic disease in families, but the specific genetic variant characteristics are not fully understood and need further research.
In addition, the significant difference in incidence among different ethnic groups also shows the importance of heredity, with studies reporting that the incidence is significantly higher in white males than in yellow males. Compared with Caucasians, most people of the yellow race maintain their anterior hairline after puberty, and the incidence of hair loss is low, the onset is late, and the progression is slower.
The drug factor is mainly manifested as hair loss caused by chemotherapy, which attacks fast-growing cancer cells and, unfortunately, other fast-growing cells such as hair cells in the scalp, eyebrows, and other parts of the body.
Hair loss caused by mental factors is mainly due to long-term anxiety or chronic stress, when cortisol is removed in a certain way, the hair follicle cells return to the anagen phase, and the hair starts to grow normally again. In recent years, with the development of genomics, metagenomics and other omics, researchers have analyzed the relationship between skin microbes and skin diseases more thoroughly.
At present, AGA research has also begun to focus on microbiology and immune cytology. Due to the large number of sweat glands in the scalp, its humidity and oil content are relatively high, forming a relatively anaerobic environment with high lipid content, which is very suitable for the growth and reproduction of microorganisms.
When the scalp microbiome is disturbed, especially the increase in the abundance of P. acnes, it seriously affects the normal growth of hair. Although there are studies to analyze the association between scalp microbes and hair loss at the molecular level, the specific mechanism of scalp microbes affecting hair growth is still not clear.
3. The dangers of hair loss
Although hair loss has no direct impact on people's life safety, due to the long course of the disease, obvious hair loss is often regarded as a manifestation of physical aging and functional decline, which makes patients feel poor self-image and lack self-confidence. As a result, patients will have symptoms such as psychological anxiety and depression, which seriously affects people's quality of life and physical and mental health.
Hair loss means that the ecological environment of the scalp is seriously deteriorated, and excessive sebum secretion causes a large number of bacteria to proliferate, resulting in damage to the scalp hair follicles, and some patients are accompanied by itching and folliculitis and other symptoms. Some patients will experience symptoms such as metabolic disorders, trace nutrient deficiencies and functional decline, and some studies have reported that hair loss is often closely related to other metabolic diseases.
People are affected by hair loss, which leads to severe damage to their image, and many problems in interpersonal communication and job search.
2. The interconnection between microorganisms and hair loss
1. Scalp microbiota
The surface of human skin is a recognized site of microbial colonization, inhabited by bacteria, archaea, fungi and viruses. These microbes help the host regulate the immune system by interacting with immune cells, affecting homeostasis and inflammation.
Although the surface of the skin is acidic, high-salt, dry, and aerobic, the invagination that forms the sebaceous units of the hair follicle is relatively anaerobic, and even more abundant lipids, which is very suitable for the growth and reproduction of microorganisms. The scalp is the place where hair depends, and the balance of its microbiota environment is particularly important for hair growth. These microbiota maintain a symbiotic relationship with the scalp and work together to maintain scalp health.
When the scalp microecology is out of balance, it is easy to breed a large number of harmful bacteria, resulting in itchy scalp, scalp and shoulder increase and even shedding. Traditionally, the exploration of the skin microbiome has been based on a culture-based approach.
Researchers can basically identify the composition of the skin microbial community by using culture technology, but in fact, the composition of skin microorganisms is much more than that, many bacteria require harsh growth conditions and are difficult to isolate, and only a few bacteria thrive in individual cultures.
With the development of various omics such as whole genomics and metagenomics, researchers have analyzed the relationship between microorganisms and skin diseases more thoroughly. At present, research on hair loss has also begun to focus on microbiology and immune cytology.
With advances in science and technology, next-generation sequencing technologies have revolutionized the way we think about human-related microbial communities, and it is now possible to characterize and analyze skin microbiota with greater breadth and precision.
2. The link between scalp microbiota and hair loss
Due to the large number of sweat glands in the scalp, its humidity and oil content are relatively high, forming a relatively anaerobic environment with high lipid content, which is very suitable for the growth and reproduction of microorganisms. When the scalp microbiome is out of balance, it is easy to breed a large number of harmful bacteria, resulting in itchy scalp, increased dandruff and even shedding.
The anaerobic and lipid-containing environment of the sebaceous units of the hair follicles makes P. acnes the dominant flora. It can not only hydrolyze triglycerides into free fatty acids, but also stimulate keratinocytes, sebaceous gland cells and monocytes to release various inflammatory factors and promote inflammatory responses.
The composition of the hair follicle microbial community in patients with androgenetic alopecia was changed, and the abundance of P. acnes on the scalp was significantly increased in patients with androgenetic alopecia, while the abundance of Staphylococcus epidermidis was significantly down-regulated. These studies have shown that scalp microbiota imbalance caused by changes in the scalp microbiota is closely related to hair loss.
3. Research progress of probiotics in the treatment of hair loss
1. Overview of probiotics
Probiotics are a class of live microorganisms that are beneficial to the health of the host and maintain the health of the body by regulating the balance of intestinal flora. In addition, probiotics also have good application prospects in regulating the skin microbiota and improving skin health.
Probiotics are able to optimize, maintain, and restore the skin's microbiota in different ways, by strengthening the skin's natural defense barrier, producing antimicrobial peptides that benefit the skin's immune response and eliminate pathogens.
Multi-omics analysis is a common means to study the disease process and the metabolic pathways of substances in the body in recent years, and it is revealed that probiotic fermentation of Astragalus membranaceus regulates intestinal flora in the treatment of hyperuricemia. Multi-omics analysis is used to reveal the changes of host-microbial interaction and aging, and multi-omics analysis will be widely used in evolutionary biology and medical research in the future.
Our research team has isolated more than 20,000 strains of healthy functional microorganisms worldwide, built a corresponding strain resource bank and genome database, and excavated the functions of their strains, and has successfully screened out probiotics that can prevent or improve human diseases, specifically in antioxidant, hypoglycemic, uric acid, sleep promotion, skin health, etc.
2. Research progress of probiotics in the treatment of hair loss
With the continuous development of science and technology and the unremitting efforts of researchers, many studies have found that the impact of probiotics on the human body is no longer limited to the intestines, but also affects other organs outside the intestines. In recent years, probiotics have shown broad application prospects in improving hair loss.
The study pointed out that the emulsifier can destroy the intestinal flora of mice and cause hair loss, and targeted supplementation of Bifidobacterium longum HK003 can alleviate and reverse this phenomenon. Long-term feeding of probiotic-deficient food to mice, mice will have slight hair loss, when the mice are malnourished and biotin levels are reduced, the hair loss phenomenon becomes more obvious, when the appropriate amount of biotin supplementation, the hair removal phenomenon is significantly improved.
Probiotics that can improve hair are isolated from kimchi, promote hair growth and reverse hair loss by improving the growth cycle. Studies have shown that diet can regulate the appearance of skin or hair, and fruits and vegetables contain a lot of vitamins, antioxidants, fatty acids and other nutrients, which have a good effect on skin or hair after consumption.
A flavonol was found in fruits and vegetables, which has the effect of promoting hair growth, and it has been found to have a good proliferative effect on DPCs in animal experiments, and can also effectively induce mouse hair to enter the anagen phase quickly. Leuconostoc minguto, isolated from human scalp tissue, induces hair growth by stimulating the growth of hair follicle dermal cells.
Feeding probiotics to aged mice quickly induced more shiny skin and hair, which was not observed in the blank control group. Lactobacillus reuteri was found to improve the hair growth cycle and promote hair growth.
Lactobacillus paracasei HY7015 can promote hair growth by stimulating the proliferation of DPCs and the secretion of hair growth factors. Compared with drugs, oral probiotics have fewer side effects and are not dependent, although the mechanism of action of probiotics to treat hair loss is not clear enough, but with the continuous development of microbiome, this new treatment method will continue to be confirmed by research.
IV. Conclusion
In summary, the imbalance of scalp and hair follicle microbiota may be the main factor leading to hair loss, especially the effect of Propionibacterium acnes on hair follicles. Probiotics, especially Lactobacillus plantarum L30 and Bifidobacterium 070310, can improve the levels of micronutrients and hair growth factors caused by androgenetic alopecia by regulating the scalp microbiota and scalp androgen balance, thereby repairing hair damage.
This study opens up a new avenue for the treatment of hair loss and lays a theoretical foundation for the development of safer and more effective foods and drugs.
This article ends here, will you sigh after reading it, it turns out that probiotics can repair hair. If you find this article helpful, you may wish to share this article with your friends.