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So What Exactly Are Stem Cells?
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 identicle 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 cells' characteristic depends on signals from the microenvironment, such as neighboring cells that form a function. Pricipally, 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 seperated 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. Th 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 relationshipof 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 bottom layer of the epidermis, and hair bulge stem cells situated in the hair follicle. The skin's top layer, the epidermis, is a stratified epithelium housing terminally differentiated cells that shed by the millions daily from the skin, continuously delivering new skin cells. Because of the fifferntiating cell dynamic, the importance of stem cells in the skin is scientifically substantiated, enumerating their relevance to skin age management. The stem cell, which is responsible for cell renewal replacement in the epedermis, is an intermediate between the keratinocyte stem cell and terminally differentiating cells. The stem cell is the amplifying cell that undergoes limited cycles of replication. One of the key questions in stem cell research has been how stem cells know when it's time to stop reproducing. In some cases, stem cells seem to be able to divide into two structurally different cells; one that remains a stem cell and another, called a progenitor cell, that goes on the generate specialized cells. Details still remain unclear, so this area of research remains active, however the study with skin stem cells reveals important information about other organs of the body. Researchers believe certain proteins and other signaling or controlling molecules are responsible for directing cell specialization, however they are still actively working to identify the specific molecules that control normal skin development. Scientists recognize skin stem cells are the decision-makers that direct the production of new skin cells, as is evidenced by the daily shedding of dead stratum corneum epithlium (the outermost layer of the skin.) If skin stem cells did not preside over and create skin replacements, they certainly would suffer a fateful demise. Skin stem cells generate new skin to replace the cells lost every day and influence wound-healing. Skin begins with a single cell. One cell, dividing into two, then two into four and four into eight until there are billions of cells, patterned and diffuse, color-coded and clear, working class and upper-crust, ancient and young, defenders and helpers, assembled into a great, thriving mass that is a complete skin organ. And from this, millions drop from the skin daily and the replication process keeps new generations of cells in a replenishment course of action that can repeat itself more than 900 times during a life cycle of self-renewal.
To learn more about stem cells and how they help with age management, join us for our Skin Care Happy Hour on August 5th from 6:30-9pm where we will be talking about "New Skin Science for Anti-Aging." You can RSVP by calling us at (636)532-1224 or email me at erind@skincaretherapy.net
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