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Stem Cell Science & Age Management of Skin
By: Christine Heathman
Posted: June 30, 2010
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Stem cells are unprogrammed cells that can differentiate into a cell with specific functions. They are related to longevity and have a unique growth characteristic allowing them to make identical copies of themselves, as well as differentiate to become specialized cells. Stem cells have the capacity to replenish themselves through self-renewal, and the ability to generate differentiated cells. Each cell, whether stem cell or differentiated cell, has the same DNA—or genes—but a stem cell’s characteristic depends on signals from the microenvironment, such as neighboring cells that form a function. Principally, there are signals inside each cell that control its fate called epigenetic signals. They are tags on the DNA or surrounding histone proteins regulating the switching on or off of genes.
The most remarkable feature of cells is their ability to reproduce. Any cell is simply a compartment with a watery interior separated from the external environment by a surface membrane, which can be thought of as a plasma film, preventing the free flow of molecules in and out of the cell. The simplest type of reproduction entails the division of a parent cell into two daughter cells. This occurs as part of the cell cycle, a series of events that prepares a cell to divide followed by the actual division process, called mitosis.
In single-cell organisms, both daughter cells often resemble the parent cell. In multicellular organisms, stem cells can give rise to two different cells: one that resembles the parent cell and one that does not.
Stem cells and skin
High-tech plant cell cultures have been harnessed to protect skin stem cells based on the science of botanical wound-healing. To understand how these ingredients function, it is important to understand the relationship of the stem cell population with other cells of the skin.
The skin. The skin is the largest and most dynamic immune organ, made up of billions of cells playing a protective and esthetic role where aging is clinically evident via wrinkles. Two types of adult stem cells have been identified within the skin’s ecosystem: epithelial skin cells located in the basal layer of the epidermis, and hair bulge stem cells situated in the hair follicle.