What is melanin? Melanin is a substance in the skin. It has the function to provide the first line in defensing against the sun. Because this substance can absorb the sun light of ultra violet (UV), so if there is a person who doesn’t have melanin in the skin. It will be dangerous, the skin can damage because the darker color of someone’s skin, so the more of the melanin in the skin is needed.
Sunbathing in long time will make the skin darken and then in responding the excessive sun light, the melanin will produce more. According to the research that has done in Florida, when a person’s skin burnt, it means that the skin becomes inflamed.
So when the skin feels warm because of the direct contact with the sun light, it becomes red. In severe case, the skin will be peeling and blistering. For the exact definition about what is melanin, it can be explained in easy way as a protein substance. It plays the role in determining the skin color.
The dark skin color has more melanin in the epidermis when it is compared with the people who have light color skin. Melanin that is exposed by the ultra violet light will make the dark spot in the skin. it can be getting worse by many factors such as pollution, stress feeling, free radical, smoking, age, and hormonal.
In the normal situation, the melanin that is produced by melanocyte cells regularly is good for the health skin. The other function of melanin is giving the color of the skin. Therefore people in this world have different skin color. This substance can protect the skin from the exposure of the sun light because actually, the sun light can destroy the structure of the skin, and make the skin darker.
However, melanin is very useful to protect the kin from the ultra violet light. The formation of this melanin can be stimulated by the light of the ultra violet. Melanin is the important pigment as a protective skin from ultra violet rays.
The pigment cells called melanocytes produce melanin in the outer skin layer. All the melanocytes produce melanin, but the cells in dark-skinned people produce more melanin per cell. There are two melanin produced by human skin, including black-brown melanin and yellow-red, pheomelanin.
Each melanin has separate biological properties. For addition, women produced about 3-4% more melanin in their skin than men. The substance of melanin is found in some parts in the body. It is including the eyes, ear, skin, and brain.
The proper function of melanin in the certain parts of human body is unknown. But some doctors declared that melanin in the certain sides in the body parts can give the hair and eyes color in human. Doctors also have a good understanding of how the work of melanin in the skin, because melanin is important to protect people from the harmful effects of the sun light.
Before the global migration, the majority of people with dark skin were living closest to the equator. Melanin absorbs the ultraviolet light, thus protecting humans from harmful UV radiation. The UV radiation can damage skin cells and improve melanoma, the cause skin cancer. European people have 10 times higher risk of melanoma than Africans.
Although melanin can do as shield, the shield will very dangerous, because the short-wave of UV radiation is necessary to penetrate the skin in producing the vitamin D. About 90% of vitamin D will be synthesized in the skin.
Melanin as The Natural Sun Screen
The ultra violet light can make the radiation, and the energy of the radiation can’t be evicted as well, unless the substance is absorbed with the other substance. The melanin is the pigment in the human skin. It can absorb the rays that are harmful and it can protect the skin from the ultra violet. But in this case, melanin has the limitation amount in absorbing the UV lights.
The color of the skin becomes darker because it absorbs the energy from the ultraviolet rays that causing the darkening skin as the effect of sunbathing. Sunburn occurs when the amount of ultraviolet light exceeds the capacity of existing melanin in the skin. People with naturally darker skin have more melanin pigment in their skin than people with white as a natural result of evolution, because some parts of the world exposed to the sun more than the other parts of the world.
What is Melanin?
Based on the true definition, melanin is the biological compounds. The compounds can be found in human body, plants, animals, and also Protista. The function of melanin is as a pigment. Pigment that has been producing is the tyrosine amino acids.
Melanin is the secondary metabolite. The secondary metabolites are the metabolites that are not essential to the growth of organisms and it is found in the unique form or it is different between one species and another. Every organism usually produces secondary metabolites were different, maybe even a kind of secondary metabolites found only in one species within a kingdom.
These compounds are also not always generated, but it is produced only when needed or in certain phases. The function of the secondary metabolites is to defend themselves from unfavorable environmental conditions, for example to cope with pests and diseases, attract pollinators, and as a signaling molecule. In short, the secondary metabolites is used by the organisms interact with the environment.
The existence of melanin can cause the diversity if the skin color in humans. Humans have the variety colors of skin with the range nearly dark or black until light or white. Men with dark skin have a higher amount of melanin, and vice versa man who has less melanin will have the white skin.
Basically, the number of melanocytes in people who have black skin or white skin is the same. The difference is the size of melanocyte cells and the spreading. In humans who have black skin, the melanocyte is larger and more evenly spread, whereas in humans who have whiter skin the melanocyte is smaller and less spreading.
In humans who have white skin, the activity of melanocytes in producing the melanin is lower than the black man. Melanin will be very useful for life creature. This means that the content of melanin in the body is not less and not excessive. The effect of excessive melanin in the skin or body is a disease that is commonly called albino. Albino can not only human but also plant and animal.
The most common type of melanin is eumelanin and pheomelanin. The most common form of melanin is eumelanin. Brown-black eumelanin is a polymer of dihydroxy indole carboxylic acids. Another form of melanin is pheomelanin a red-brown and is a polymer of benzothiazine. Melanin is responsible for providing the color red hair and freckles. Pheomelanin and eumelanin are found in human skin and hair. But eumelanin is the most abundant melanin in humans.
The Main Function of Melanin for Human Being
Melanin is pigment that produced in the skin of most creatures on earth. His role in the survival of the creatures is very important, and the varieties depend on the organism. Skin color is the characteristic that is influenced by some factors, variety genes, factors of nutrition, and factor of environment may hold the role in skin color. The most important components of the skin that hold the contribution to skin a pigment is popular with the name melanin.
Melanin is the pigment produced by the cells that are known as melanocytes in animals and plants, including humans. This pigment is presented in different types, depends on the genetic cells of each person. Melanin appears in basic forms. There are 2 forms that can reach the range from yellow and brown color of the skin until dark red. Eumelanin is the most usual form of melanin, and brown.
The basic name type of melanin is namely pheomelanin, which can produce the red or brown color which is often related to the red hair and freckles. In production of pigment melanin in each people is determined by a few factors. In general, people have the exactly number of amount of melanocytes.
What make it different of the melanin production is effected by some factors such as:
- The exposure of ultra violet radiation
Melanin is produced as the response to UV radiation. The pigment melanin can protect the damage of the skin until the DNA. People, who are get more exposition of UV light or has more activity outdoor will produce more melanin for protection through the skin then the people who has the activity inside the room
The ethnic and the different culture are genetic. It is related to the production of particular colors and the amount of the melanin based on the inheritance. It becomes main indicator that to determine the human race in certain population.
- The size of melanocytes
The sizes of melanocytes are various in different individuals, and it may bring to how much melanin produced in each cell.
- The disease
Some diseases can affect the production of the melanin, including the albinism and vitiligo.
Problems with Melanin
In humans, melanin production is important for the prevention of skin cancer, such as melanoma. This means that the skin becomes darker in most individuals when the skin is exposure by the excessive sun light. In addition, the overgrowth of melanocytes may bring to the development of moles on the skin. A mole or nevus, usually benign or not threatening, but it can become the cancer disease with the increasing of the exposure to sunlight.
The Role of Melanin for Human’s Skin
The human skin is composed of two layers, the epidermis and dermis. The epidermis in the top layer in human skin has a different thickness about 400-600 μm thick skin and 75-150 μm for thin skin. Thin skin is the skin in hand, feet and hair. The epidermis is composed in layers such as
- The melanocytes is the cells that produce melanin through melanogenesis
- The Langerhans cells are the cells that are constituted the bone. Langerhans cells play an important role in skin immunology.
- Merkel cells are the cells that serve as sensory mechanoreceptors and related to the functions with diffuse neuroendocrine system.
- Stratum Corneum consists of 15-20 layers of flattened cells, without the nucleus to the cytoplasm.
- Stratum Lucidum consist of a thin layer of epidermal cells eosinophilia that is very flat and the thick cytoplasmic consists of keratin. There are desmosomes between cells.
- Granular layer is composed of 3-5 layers of flattened polygonal cells cytoplasm that contains granules keratohialin. In the lamella granule cell membranes are issuing an adhesive material between the cells, which work as a filter selectively against the entry of foreign materials. It can protect the skin.
While the dermis, it is the layer of skin below the epidermis. It has various thicknesses, depending on the area of the body. And it reaches a maximum of 4 mm in the back. The dermis is composed of two layers with no real limits. They are stratum corneum papilare and reticular.
- Straum Papilare
This is the main part of papillary dermis. It is composed by the loose connection tissue. In this stratum, we can find fibroblast, mast cells, macrophages, and leukocytes.
- Stratum Retikulare
It is thicker than the stratum papillary dermis.
Dermis also contains several derivatives of the epidermis, the hair follicles, sweat glands, and sebaceous glands. Hair is a long keratinized structure that derived from epithelial invagination of the epidermis, the hair follicles. In these follicles are widening terminal shaped bumps on a papillary dermis. The dermal papilla contains capillaries and it is covered by the cells that will form the hair cortex, hair cuticle and hair root sheath.
Sebaceous gland is a holokrin gland. It is immersed in the dermis with varying amounts ranging from one hundred to nine hundred per square centimeter. The secretions from the sebaceous glands is sebum, which is composed of a mixture of lipids include triglycerides, wax, and cholesterol.
At the bottom of the dermis, there is a loose connective tissue called the subcutaneous tissue and cells containing various fats. This tissue is also called superficial fascia, or panikulus adiposus. This tissue contains a rich tangle of blood vessels and lymph vessels.
Arteries that are formed two plexus, one of the stratum papillary and retikulare, another one in between the dermis and subcutaneous tissue. The branches of the plexus fill the papillary dermis. While the venous plexus formed in three, two are located such as arteries, one in the mid-dermis.
The lymphatic vessels have the same location with arteries. To support the skin functions as a recipient of stimulus, then there are many nerve endings, among others in the epidermis, hair follicles, cutaneous glands, dermis and subcutaneous tissue, and papillary dermis.
These nerve endings respond to stimulate such as palpation-pressure, tactile sensations, high – low temperature, pain, itching, and other sensations. In addition, nails are keratinized epithelial cell plate on the dorsal surface of each of the distal phalanx. Nail plate is located on the stratum corneum, while the base of the nail lies on a stratum basal and spinosum.
The Effect Lack of Melanin
Gray or white hair on the head is a sign of getting old age. Although there are also people who identified it with the maturity and tact. But what is the reason if the strands of the gray hair come at the young age? If that happens, then it means there is no running normally in the body.
The question is why gray hair can grow faster? What are the causes and how to solve it? Gray hair that appeared too early can occur in men and women. Although men look more often experience, there are many young women with gray hair. It’s just that most women are able to cover his gray with some ways that are not apparent on the surface. The occurrence of gray hair is caused due to shortage of the color pigment melanin in the hair.
Melanin is produced by melanocytes in the hair follicle. The cause of the reduced melanin is influenced by several factors, among these psychological factors, lack of oxygen in the blood, the influence of drugs, age, and heredity. But for a young age, it is mostly influenced by the heredity and psychological. For example, the psychological factor could be due to the stress that affects the production of melanin hair.
The other effect in lack of melanin in the skin is the albinism. Albino is a term to call person who does not have a color, or pigmentation. All races have a certain amount of pigmentation, although some of them with white race only have it in very small amounts.
What causes the color or pigmentation in humans? It is produced by certain substances in the body that is mutually acted with each other. This substance is a basic color or chromogenic, as the resulting of pigmentation. If one does not happen to have one of these substances in their bodies, no pigmentation, and he became albinism.
The word comes from the Greek word “albus, meaning white” Someone who is albino has pink eye, and it is caused by the red blood that seems to flow in retina. The eyes of the albino are sensitive to light. So albinos are always keeping his eyelids half closed with blinking.
The hair in the body is also white. Even in his body tissues such as the brain and spinal cord white. Albinism is not only found in humans, but also in plants and every kind of animal even at the birds. And no human race doesn’t have albino.
It is believed that albinism may be declining and many people are not albino but pass this characteristic to their children. Perhaps the most familiar albino rats and rabbits are white. It is doubtful for those who never see albino squirrels and even an albino giraffe.
Vitiligo is a condition in which the skin loses melanin. The pigment determined the color of the skin, hair, and eyes. This happens due to the cells that produce melanin lives no longer. As the result, the skin pigment fading and white patches appear in an irregular shape that the longer size can be enlarged.
Although all parts of your body can be affected by vitiligo. However, usually vitiligo will occur in sun-exposed areas first, such as the hands, feet, arms, face, and lips. Genitals may also be affected by this disease. Vitiligo knows no racial, it can happen to anyone.
However, new vitiligo is often experienced with the age around 10 to 30 years. Vitiligo appeared in three patterns. The first type is generalized. This pattern is the most common pattern of vitiligo. The missing skin pigment is widespread in many parts of your body and symmetrically shaped.
The second pattern is segmental. The skin color is lost only occurs on one side of the body. This type of vitiligo is often experienced by young people. This type occurs for approximately one to two years and then stopped. And the last type is focal.
This type happened only one or few area in the body. This disease can be detected soon with the use of ultra violet or the skin biopsy. In skin biopsy, the doctor will take a small sample of tissue in the skin area that is pigmented to determine whether that is vitiligo or not. And the last step is blood test.
The doctor will take the blood to count and check thyroid function blood cells and for the presence of anti-nuclear antibodies that can indicate an autoimmune disease. Vitiligo disease can occur when the cells that produce melanin die.
As a result, the skin loses melanin determine the pigment in the skin, eyes, and hair and appeared patches of milky irregular on the skin. However, doctors and scientists also had the theory which stated that vitiligo occurs when the body experiences a disruption of the immune system.
More than that, heredity, emotional state, excessive exposition to the sun light, and have a history of melanoma also increase that risk of developing vitiligo. The main symptom of vitiligo that appears physically is skin color faded and turned into milky white patches. Moreover, the person who is affected will experience bleaching or growth of gray hair on the scalp prematurely. In addition, the tissue that lines the inside of the mouth and the inner lining of the eye or retina will lose the color.