Stem cell therapy for repair and regeneration of tissues and organs damaged by trauma or degeneration is now used in many fields of medicine. The mesenchymal stem cells are one of the major stem cell types used in regenerative medicine. They can be obtained from several tissues, including the subcutaneous adipose tissue, and used either immediately or after their expansion in vitro.
Mesenchymal stem cells have been used extensively in skin therapies, because they have a broad paracrine action on dermal cells; they stimulate angiogenesis; they protect other cells from the peroxide-mediated damage; and also modulate inflammation, pain, and immune tolerance. Experimental studies also suggested the role of adipose-derived stem cells in improving quality of the aging skin, but we still need extensive clinical studies concerning the histologic changes of the human skin that was exposed to local interaction with adipose-derived stem cells.
In the skin showing photoaging, a progressive degeneration of the entire elastin network occurs in the deep dermis. Major elastic fibers become thickened, tangled, tortuous, degraded, and dysfunctional, setting the solar actinic elastosis, the most relevant feature of the photoaged skin. The overall marked loss of collagen and the thickening of elastic fibers cause accumulation of the dysfunctional elastic component in the skin of elderly humans compared with young ones.
Stem cell treatments ‘go deep’ to regenerate sun-damaged skin
Dr. Luis Charles-de-Sá, MD, of Universidade Federal do Rio de Janeiro, Brazil, Natale Gontijo-Amorim, MD and Gino Rigotti, MD of Verona-Italy University and colleagues, assessed the cellular- and molecular-level effects of MSC treatment on sun-damaged (photoaged) facial skin.
All 20 patients in the study, average age 56 years, were scheduled for facelift surgery. The patients lived in northeast Brazil, a region where intense sun exposure is expected.
For each patient, a small sample of fat cells from the abdomen was processed to create patient-specific MSCs. The cultured stem cells were injected under the skin of the face, in front of the ear. When the patients underwent facelift surgery three to four months later, skin samples from the stem cell-treated area were compared to untreated areas.
Histologic and structural under the microscope analysis demonstrated that MSC treatment led to improvement in overall skin structure. Treated areas showed “partial or extensive reversal” of sun-related damage to the skin’s stretchy elastin network , the main skin structure affected by photoaging. In the layer immediately beneath the skin surface, the stem cell-treated areas showed regeneration of a new, fully organized network of fiber bundles and dermal extracellular matrix remodeling changes.
In the deeper skin layer, “tangled, degraded, and dysfunctional” deposits of sun-damaged elastin were replaced by a normal elastin fiber network. These changes were accompanied by molecular markers of processes involved in absorbing the abnormal elastin and development of new elastin.
As we can see, the findings suggested that stem cells triggered each of the many cellular- and molecular-level pathways involved in skin repair and regeneration. Use of the patient’s own fat-derived MSCs may be a relevant proposal for the anti-ageing action in regeneration of photodamaged human skin; it would be interesting to investigate whether other types of stem cells such as umbilical cord MSCs could have the same benefits.
Charles-de-Sá, Luiz M.D., Ph.D.; Gontijo-de-Amorim, Natale Ferreira M.D., Ph.D.; Rigotti, Gino M.D., Ph.D.; Sbarbati, Andrea M.D., Ph.D.; Bernardi, Paolo Ph.D.; Benati, Donatella Ph.D.; Bizon Vieira Carias, Rosana Ph.D.; Maeda Takiya, Christina M.D., Ph.D.; Borojevic, Radovan Ph.D. Photoaged Skin Therapy with Adipose-Derived Stem Cells (June 2020). Plastic and Reconstructive Surgery. Retrieved from : https://journals.lww.com/plasreconsurg/toc/2020/06000
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