Investigation of age-related decline of microfibril-associated glycoprotein-1 in human skin through immunohistochemistry study

Abstract

During aging, the reduction of elastic and collagen fibers in dermis can lead to skin atrophy, fragility, and aged appearance, such as increased facial wrinkling and sagging. Microfibril-associated glycoprotein-1 (MAGP-1) is an extracellular matrix protein critical for elastic fiber assembly. It integrates and stabilizes the microfibril and elastin matrix network that helps the skin to endure mechanical stretch and recoil. However, the observation of MAGP-1 during skin aging and its function in the dermis has not been established. To better understand age-related changes in the dermis, we investigated MAGP-1 during skin aging and photoaging, using a combination of in vitro and in vivo studies. Gene expression by microarray was performed using human skin biopsies from young and aged female donors. In addition, immunofluorescence analysis on the MAGP-1 protein was performed in dermal fibroblast cultures and in human skin biopsies. Specific antibodies against MAGP-1 and fibrillin-1 were used to examine protein expression and extracellular matrix structure in the dermis via biopsies from donors of multiple age groups. A reduction of the MAGP-1 gene and protein levels were observed in human skin with increasing age and photoexposure, indicating a loss of the functional MAGP-1 fiber network and a lack of structural support in the dermis. Loss of MAGP-1 around the hair follicle/pore areas was also observed, suggesting a possible correlation between MAGP-1 loss and enlarged pores in aged skin. Our findings demonstrate that a critical “pre-elasticity” component, MAGP-1, declines with aging and photoaging. Such changes may contribute to age-related loss of dermal integrity and perifollicular structural support, which may lead to skin fragility, sagging, and enlarged pores.

The Effect of Ultraviolet B on Fibrillin-1 and Fibrillin-2 in Human Non-pigmented Ciliary Epithelial Cells <i>In Vitro</i>

“…The triple helical [α1(I)] 2 α2(I) band of type I collagen was not affected by UV-B irradiation between 1 and 500 mJ/cm 2 . Moreover, human dermal fibroblasts irradiated with UV-A at a level of 10 mJ/cm 2 followed by 50 mJ/cm 2 UV-B at 24-hr intervals led to a reduction of fibrillin-1 and microfibril-associated glycoprotein (MAGP)-1 [ 22 ], mimicking the conditions occurring in vivo . Therefore, the sensitivity of oxytalan fibers and collagen fibers to UV-B appears to differ, suggesting that the observed changes in microfibril microstructure may be explained by loss of oxytalan fiber continuity, as demonstrated in our immunofluorescence study with irradiation at 150 mJ/cm 2 .…”

Elastin structure and its involvement in skin photoageing

“…Components such as fibrillins, fibulins, microfibril-associated glycoproteins (MAGPs) -mainly MAGP1 and MAGP2, and proteoglycans form a scaffold in which tropoelastin molecules are deposited on preformed bundles of fibrillin microfibrils in the pericellular space [14,46,48]. The microfibril template thus profoundly influences tropoelastin deposition and the organization of mature elastic fibres as well as their biomechanical properties [43,45].…”

Facial Skin Lifting and Brightening Following Sleep on Copper Oxide Containing Pillowcases

“…These ECM structures, made up mostly of collagens I and III, elastin and fibrilin fibers, and glycosaminoglycan-rich proteoglycans, strongly interact with each other providing the skin with strength, extensibility and elasticity [1]. With age, the amount and size of fibroblasts in the dermis decreases, as does the production of ECM by fibroblasts that remain in the skin [2][3][4][5][6]. This results in changes of the skin's structure and appearance, including a marked loss of skin elasticity and recoil, increased appearance of wrinkles and facial sagging skin, especially under the eyes [7][8][9][10][11].…”