Early Fetal Development
By the end of eight weeks’ gestation, the basic components of most organ systems have been laid down. Over the next several weeks, more layers are added to the intermediate zone of the epidermis, such that by 22-24 weeks, the epidermis contains four to five layers in addition to the periderm. After the onset of stratification, the basal layer becomes more cuboidal and begins to synthesize keratin peptides (K6. K8, K19, and the K6/K16)^25,26. This latter keratin pair is not normally expressed in mature inter follicular epidermis. During early development, the basal cell layer also begins to express the hemidesmosomal proteins BPA1 and BPA2, and to secrete collagen types V and VII.
Late Fetal Development
Maturation of the epidermis during late fetal development is characterized by granular and stratum corneal layers, the formation of a water-impermeable barrier, and the sloughing of the periderm. Keratinization is first initiated in the skin between 11 and 15 weeks. Initiation of keratinization is characterized by an increase in cytoplasmic density of keratinocytes. The early granular layer continues to matter with the formation of more granules. More superficial ;ayers undergo terminal differentiation, resulting in the formation of transglutaminase-mediated cross-linked envelopes. At later stages the terminal differentiation is more complete, resulting in the complete absence of organelles in keratinized cells. During the third trimester, the cornified cell layers increase in number. Although the third-trimester stratum corneum is structurally similar to that of an adult, functional studies indicate that it is much less effective at preventing water loss.
all these processes contribute to the perfect appearance of newborn skin- a golden standard for cosmetology. However, skin appearance of premature and post mature infants does not conform to golden standards.
All skin layers (i.e. epidermis, dermis, and subcutaneous fat) are thinner in the preterm infant than at term. ^2,3 Stratum corneum begins to form around hair follicles at about 14 weeks’ gestational age. During the ensuing weeks, the thickness of the stratum corneum increases to several cell layers. the ‘excess,’ outermost layers of the stratum corneum are then shed during the first days of life; this process of physiologic desquamation is accentuated in postmature babies. As pregnancy progresses, the skin becomes less transparent indicative of a thickening stratum corneum.
our original hypothesis was that Wharton Jelly proteins contribute to the youthful appearance of healthy newborn skin by stimulating skin stem cells. The amount and quality of Wharton Jelly content are directly related to skin appearance. The abnormally thin umbilical cords in premature babies and devitalized and the wrinkled cords found in post mature newborns have an effect on skin status.
Fetal skin is link to an invaluable source of stem cells, many of which migrate from the Wharton’s Jelly. One out of every 200,000,000 cord blood cells is a stem cell, while one in every 300 of the Wharton Jelly cells is an omnipotent stem cell. The true anti-aging frontier in cosmetic research lies in the exploration and application of a specific peptide from Wjharton Jelly to incite the safe and efficient arousal of stem cells in adult skin and, thereby, to duplicate in adult skin and the magnificent regenerative process seen in fetal skin. Research was conducted on a complex of bioactive substances from embryonic tissue-Wharton’s Jelly. Wharton’s Jelly is the least studied part of the composition of the umbilicus, which indispensable in the fetal blood supply. As a result of years of scientific work, it has become possible to isolate such a substance and synthesize it chemically. The preparation was called Wharton Jelly Peptide P199. It was shown that in a cell culture, Peptide P199 causes an increase in the expression of IL-1, IL-3, IL-6, IL-8, keratinocyte growth factor, fibroblast growth factor, epidermal growth factor, and endothelial growth factor, i.e., the cascade of cytokines and growth factor necessary for the activation of stem cell proliferation and differentiation processes for the purpose of initiating effective cellular renewal of skin.
Methods And Materials
the purpose of the present study was to determine the effect of Peptide P199 on the activity and proliferative capacity of stem cells in human skin samples. The epidermal stem cell content was evaluated based on the expression of the following markers: B1 integrjn , cytokeratin 15 and cytokeratin 19. According to the data from the literature*, B1 integrin, cytokeratin 15 and cytokeratin 19 are putative markers of epidermal stem cells. The study was performed on skin biopsy samples obtained as a result of a facelift with the voluntary consent of the patients. 15 patients, aged 35-45, were selected. A significant increase was seen for cytokeratin 19 positive cells in 2.4 time. A significant increase was seen for cytokeratin 15 positive cells in 3.5 times. An increase was noted in B1 integrin.
A cream containing th peptide was used on both sides of the face for 28 days. Upon completion of the 28 day treatment a second biopsy was taken from the opposite parotid region than the first. Histological sampled were taken from the biopsy and stained with hematoxyline-eosin. The samples were visualized with digital photography through a fluorescent microscope. Total collagen was determined through collagen autofluorescense via computer image analysis.
The post treatment tissue vowed significant changes to the papillary and superior reticular dermal layer, consisting of new collagen fibers with parallel distribution to each other and reduced thickness. These results show topical treatment with the peptide P199, led to improved fibroblast functionality and resulted in the synthesis of new collagen fibers with better-organized distribution.
Agin starts when cells stop growing. Skin aging can be decided into distinct group depending on ethnic origin. Thus, in Caucasions, first signs of aging can be seen on the face (38-41%), then salt tissues (abdomen, buttocks, breasts-10-15%). Then hands and legs.
Types of Aging:
1) Granitational- Tired face
As we age, people with granitational type of aging retain fluid in soft tissues behind the epidermis, It manifests itself as “bags” under the eyes, dropped corners of the mouth, and hanging cheeks.
2) “Baby Face” aging
So called “Baby face” aging occurs when people contain large amounts of sobcotenous fat, which with time can not be adequately supported by collagen carcass. fat globules start to prolapse which then manifests itself as hanging cheeks, as well as upper lids and facial deformation.
3) Muscular aging
People with well developed facial muscles age in a different fashion. muscles when in action, cause and collagen disruption of the overlying skin, This results in the formation of multiple wrinkles, mostly on the forehead, and around the eyes and mouth.