Nature's Impact
December 1997
Feature Story: Beta-1,3-D-glucan: The Skin Connection
By Leonid Ber, MD

    Beta-1,3-D-glucan is a polysaccharide that has recently become available as a dietary supplement. It is derived from the cell walls of yeast (Saccharomyces cerevisiae ) and is known as a potent macrophage activator,. It works through beta-glucan receptor on the surface of these cells.
    Macrophages ("big eaters") are the cells that recognize, engulf and destroy any cells, organisms and substances that don¹t belong to the body (bacteria; viruses; fungi; bits of necrosed or changed tissues; dead, mutated or tumor cells; heavy metals; etc.). Unlike other immune cells, macrophages act non-specifically. In other words they respond similarly no matter what kind of challenge they face. Macrophages are the cells that start and regulate the immune process. They ignite itercellular communication via release of chemical messengers called cytokines (such as interleukins, growth factors, colony-stimulating factors, and interferons).
    Macrophages can travel from the site of the first contact with bacteria (or other intruders) to the lymph tissues. This is where the macrophage communicates with T-cells, activating a specific immune response and building specific antibodies to combat this specific intruder.
 

Langerhans Cells

    Macrophages are present in all the organs of our body including blood, liver, nervous tissue and skin. We used to think of skin as an outer shield. In actuality, skin is the largest immune-system organ in our body. Its upper layer, epidermis, contains up to 5 percent of macrophages or Langerhans cells, the primary cells of the immune system. These cells owe their name to a 19th-century German anatomist and microscopist, Paul Langerhans. (He also discovered so-called "Islets of Langerhans" in the pancreas, which are the insulin-producing areas of this endocrine organ.)

    Macrophages in the epidermis have a very special appearance. Each cell has a body and long-reaching extensions of cytoplasm. Because of these extensions, Langerhans cells literally form a fishnet within the upper layer of the skin,reaching most of the skin cells.
    The role of Langerhans cells within the epidermis is extremely important. They carry out defensive and regulating functions within the skin. As with any macrophage, Langerhans cells are initially manufactured in the bone marrow. After being released from the bone marrow, it becomes a monocytes (blood macrophages). Later, they enter the skin through the capillaries and become a specialized epidermal macrophages - Langerhans cell.
    Langerhans cells play a key role in maintaining the integrity of the skin. The skin constantly faces microscopic wounds, so it needs to repair itself on an ongoing basis. When the skin is damaged, macrophages are responsible for cleaning and restoring it. Some individual¹s skin is almost permanently damaged as a result of occupational exposure. This may include daily household exposure to the chemicals in cleansers and detergents. As we age, as the immune system¹s ability to respond to the new challenges declines. The skin becomes less able to heal itself and cope with infections.
    Macrophages, when activated, can prevent or stop growth of infectious agents by attacking and destroying bacteria. At the same time, macrophages can release substances such as the epidermal growth factor, that encourage skin renewal. Therefore it is important to have macrophages (Langerhans cells) fully functional in the skin, especially aged skin.
    Beta-1,3-D-glucan appears to be a substance that activates and supports all these macrophage functions.
 

Beta-1,3-D-Glucan In Skin Care

    The effect of a cosmetic regimen containing beta-1,3-glucan on the signs of aging in the skin was evaluated in 150 women, ages 35 to 60. A 27 percent improvement in skin hydration was observed after eight weeks of using the regimen twice a day. A measurable improvement in lines and wrinkles at the end of the study reached 47 percent, firmness and elasticity increased by 60 percent and skin color improved by 26 percent. Skin renewal was increased by 34 percent compared to the control group.
    The cosmetic products ( serum and cream ) containing this powerful ingredient at a concentration of 10 mg per ounce were applied after use of an exfoliating toner containing salicylic acid. Use of an exfoliator prior to beta-glucan application was important. It removed the very superficial layer of the dead skin, thereby exposing more Langerhans cell extensions to this ingredient.
    While other ingredients are thought to be effective only when they penetrate the skin, glucan is actively taken into the cells. Plenty of exfoliating products on the market today contain either alpha, beta- or a combination of hydroxy acids. When used at certain high concentrations, these acids can produce a significant irritation. Beta-1,3-D-glucan significantly reduces such irritation; it produces fast and powerful healing effects on the chemically stripped skin.

 
UV-Light and Beta-1,3-D-Glucan

    Langerhans cells in the epidermis are very sensitive to environmental factors. One of the factors that can damage these cells function is ultraviolet (UV) light.
    We know that UV light can suppress immune function. In fact, UV light has been used to treat certain autoimmune skin diseases.
    After even a brief exposure to UV light, the skin loses some Langerhans cells. This may explain at least partially how UV light undermines the immune system. When the first cell in the immune reaction chain is not in place, the rest of the immune system has trouble functioning. Lack of immune protection means a higher rate of infections and tumors.
     Investigators at MD Anderson Cancer Center in Houston suggested that conventional sunscreens, while reducing sunburn, do not provide adequate protection from certain skin tumors, including melanoma. Between 1973 and 1992, despite wider use of sunscreens, mortality from melanoma increased 34 percent - the third highest increase of all cancers.
    The effect of UV light on occurrence of other types of tumors is also suspected. Immunosuppression caused by UV radiation affects the whole body. It can even be measured in remote parts of the body that have not been exposed to the radiation.
     How does UV cause Langerhans cells to disappear? UV light creates an enormous amount of free radicals within the skin cells. Eventually, these free radicals can damage the healthy cells irreparably. An arsenal of intracellular antioxidants provides only partial protection. Melanin, a potent free-radical scavenger and photoprotector, is produced by specialized cells called melanocytes. Melanin is also responsible for the color of tanned skin. When melanocytes synthesize and release melanin, it is distributed throughout the skin and becomes incorporated into the epidermal cells, but not into Langerhans cells. This is why even in tanned skin, UV-light exposure still causes the disappearance of Langerhans cells and, consequently, suppresses immune function.
     Experiments with beta-1,3-D-glucan indicate that it protects Langerhans cells after UV-exposure. In this study, a 0.05 percent external application of beta-1,3-D-glucan prevented redness of the skin, skin cell damage and depletion of Langerhans cells by more than 50 percent. This remarkable effect would be easy to explain if beta-glucan was a sunscreening agent. Sunscreens do protect skin cells by absorbing the UV-rays; however, beta-glucan is not a UV-absorbing substance!
     A specific receptor on the extensions of the Langerhans cells recognize and then internalize beta-1,3-D-glucan. As a result, Langerhans cells become activated and more resistant damage. When in the cytoplasm, beta-glucan also becomes a free radical scavenger, especially effective against hydroxyl radical - the most abundant free radical after UV-radiation. This combination of cell activation and free-radical scavenging ability allows protection of vulnerable Langerhans cells from the effects of UV-radiation. This helps these cells continue their important defensive and regulating functions in the skin. Eventually, they can reduce the risks of UV-related immunosuppression.
     Researchers agree that certain types of UV light (UVA) are more damaging to the immune system although they cause less sunburn. Modern FDA-approved sunscreen strength is measured by its ability to prevent redness (so called SPF, sun-protecting factor), which is generated mostly by the UVB spectrum. Unfortunately, even if sunscreen prevents sunburn, it doesn¹t necessarily protects immune function. Immunosuppression is the major culprit in tumor development.
    When buying a sunscreen - make sure that it protects against both UVB and UVA parts of the spectrum. You can also enhance the photoprotective effect of sunscreens by using a substance that specifically addresses your skin¹s immune system. Presumably, a sunscreen and beta-glucan combination would be your best choice.
    UV light is thought to be only one of many environmental agents that can alter Langerhans cell function. Infection with viruses, notably HIV and viral hepatitis, can "turn off" Langerhans cells. A study by Kenyon (1983) showed that chronic viral infections were associated with impaired wound-healing capability. This impairment could be overcome by placing the macrophage-stimulating glucan into the wounds.
 

Wound-Healing Properties

    The wound-healing ability of beta-1,3-D-glucan in general has been firmly established. One study tested several topical agents, and only glucan showed any marked beneficial effect. Twenty mg of beta-1,3-D-glucan was applied per each one cm incision. Glucan-treated wounds resulted in a higher number of macrophages. Hence, re-epithelization (formation of new surface layer tissue) started earlier in the glucan-treated wounds than in the control subjects. Five days after wounding, glucan-treated wounds were generally completely re-epithelized. Completely scar-free healing occurring within 10 days. Control groups during the same 10 day period were still in some stages of tissue restructuring.
    When beta-glucan was used as a salve for chest wall ulcers following surgery and irradiation for breast cancer, these ulcers were healed with no sign of infection. Beta-glucan was applied to the indolent (inactive) pressure ulcers of 31 patients with indolent pressure ulcers were treated with the topical application of beta-glucan at the Charity Hospital in New Orleans. During this short, five-day study, an overall 73.3 percent of ulcers decreased in size and showed significant improvement. As many as 26.7 percent of glucan-treated wounds closed completely with the formation of smooth, normal-appearing skin.

 
Beta-Glucan And Melanoma

    Aside from its external use, researchers have investigated the injectable application of glucan into skin tumors. Dr. Peter Mansell conducted the first series of injections of beta-glucan into small swellings beneath the skin of patients with malignant melanoma. He used dosages of the active ingredient in a range from 10 to 100 mg per injection. Dr. Mansell found that a mass od activated macrophages had replaced the malignant nodules.
    Beta-1,3-D-glucan has been known to attract macrophages. More activated macrophages appeared at the site of injection and continued attacking melanoma cells. the macrophages also kept recruiting other immune cells, thus promoting healing and replacement with normal tissue. In certain human and animal cases, uninjected nodules of melanoma also disappeared. In some cases, tumor growth in remote parts of the body was controlled during this therapy, but the growth started again once the treatment ended.This data confirms the fact that the skin macrophages are intimately involved in entire immune system function.
 

Summary

     Beta-1,3-D-glucan is a polysaccharide that consists of specifically arranged glucose molecules. This ingredient activates macrophages cells, thus promoting a more powerful immune system.
     Aside from being effective orally (not a subject of this article), beta-1,3-D-glucan can also be externally applied for good results. The benefits include skin rejuvenation, prevention and treatment of UV-related skin damage and wound healing. Additionally, beta-1,3-D-glucan may be injected into certain types of skin tumors. However, this use - although shown to be effective almost 20 years ago - has not been widely utilized.