Neuropeptides: The Information Superhighway to Cellular Repair
The skin has abundant nerve endings whose role is to provide information to the brain. It is also composed of many different types of cells, such as fibroblasts and keratinocytes, as well as messengers such as hormones, neuropeptides, and neurotransmitters. When the skin is challenged by an environmental stressor such as the sun or by physical or mental stress, its responsibility is to provide information to all of the other organ systems in our bodies. In other words, the skin can function very much like the brain or the endocrine system in providing important data to the body.
When we are in an embryonic state, the layers of cells that eventually develop into skin are also responsible for making brain cells. This means that the skin and brain are very closely connected. I refer to this as the brain–beauty connection, and as you will learn, it clearly indicates that the skin is much more than just a protective barrier. The skin also has receptor sites for all the different types of messengers mentioned above. This means that the skin can not only transmit messages throughout the body but also receive messages by way of neurotransmitters, neuropeptides, hormones, and nerve impulses. This information was revelatory for scientists, who knew that the brain communicated with other organ systems but did not realize that the rest of the body was responding! This information superhighway communication system opened doors to a much greater understanding of the entire mind–body connection and its role in physical and mental health. This discovery is extremely relevant when we look not only at diseases of the skin but also at mental diseases and disorders. By just stimulating the skin, you can actually change the chemistry in your brain. Conversely, your skin will show the result of anxiety attacks and depression.
This is of tremendous importance to dermatologists and their patients because historically many skin diseases have been categorized as having an unknown etiology (the cause or origin of disease). This has made many skin diseases notoriously difficult to treat. However, we know that these diseases have a significant inflammatory component and that diseases such as acne, psoriasis, and atopic dermatitis are all deeply affected and even precipitated by mental stress. Any acne sufferer will tell you that new lesions always appear right before an important event—and that is no coincidence. This adds a new level of truth to the aphorism “You are what you eat” and proves that you are also what you think and feel.
If we are to age successfully, looking and feeling good into advanced decades, we must remember these two simple yet incontrovertible facts: The foods we eat not only affect our physical health but also profoundly affect our mental attitudes and our sense of wellbeing, especially where stress is concerned.
When we experience stress, a neuropeptide known as substance P (SP) is released into both the skin and the brain. SP is a strong, proinflammatory molecule. When released into the skin, it starts a flow of pro-inflammatory chemicals, resulting in the activation or exacerbation of skin disease. SP can also slow hair growth and cause hair loss because of its ability to affect hair follicles. SP also affects the sebaceous glands (glands in the skin that produce sebum, an oily substance) by making them more active and by affecting their growth and creating the inflammation that can clog pores. It is interesting to note that the skin of acne patients has a much greater number of these SP-containing nerves than the average person. Thus we can see the brain–skin connection is a powerful one, mediated by neuropeptides, with the final common pathway, as always, being inflammation.
Posted in Skin Health
