Matrix Metalloproteinase-1 Production Observed After Solar-Simulated Radiation Exposure is Assumed by Dermal Fibroblasts but Involves a Paracrine Activation Through Epidermal Keratinocytes¶

Long-wave Ultraviolet Ray Promotes Inflammation in Keloid-derived Fibroblasts by Activating P38-NFκB1 Signaling Pathway

One of the main mechanisms of keloid formation is the persistent chronic inflammation, which initiates the activation of keloid-derived fibroblasts (KFs) and boosts the production of extracellular matrix. Meanwhile, 95% of the ultraviolet rays that reach the earth are long-wave ultraviolet (UVA). However, the effect of UVA on keloids is currently unclear. The objective of our research is to investigate UVA's impact on keloids. Cell viability assay, migration assay, and cell cycle analysis were conducted. UVA's impacts on gene expressions were detected by real-time quantitative polymerase chain reaction, western blot analysis, enzyme-linked immunosorbent assay, and immunofluorescence. Our results indicated that UVA inhibited the proliferation and migration of KFs. In addition, after UVA irradiation, the expressions of matrix metallopeptidase 1 and matrix metallopeptidase 2 markedly increased in KFs. Moreover, the expression of α-smooth muscle actin and collagen I decreased. Furthermore, KFs with UVA irradiation secreted more interleukin-6 and interleukin-8 in the culture medium. And it was confirmed that the protein expressions of inflammation-related factors, including P38, CK2A, NFκB1, and P65, increased observably in KFs with UVA irradiation. The protein expression of IKBα, also known as NFκB inhibitor α, decreased. All these observations suggested that UVA irradiation could inhibit cellular activity and collagen production in KFs while promoting inflammation by activating P38-NFκB1 signal pathway.

Formulation, Characteristic Evaluation, Stress Test and Effectiveness Study of Matrix Metalloproteinase-1 (MMP-1) Expression of Glutathione Loaded Alginate Microspheres and Gel

Background: The present study aimed to formulate and evaluate the stability, characteristics and effectiveness of glutathione-loaded alginate microspheres through increased lipophilicity using surfactant with a Hydrophylic-Lipophilic Balance (HLB) value equal to 7. The selection of glutathione as an antioxidant was based on its prominent role in maintaining intracellular redox balance. Alginate was used as the polymer, while calcium chloride constituted a cross-linking agent and Tween and Span were employed as surfactants. Methods: The study applied an ionotropic gelation-aerosolization method. Microspheres were characterized by their morphology, size, drug loading, entrapment efficiency and yield. Stress testing utilized a forced degradation method, while an effectiveness study of glutathione incorporated a Matrix Metalloproteinase I (MMP-1) parameter on mouse skin. Glutathione-microspheres, to which had been added surfactants with a HLB value equal to 7, were compared to those without surfactants. Results: Microspheres demonstrated both high yield and encapsulation efficiency. From the stability study conducted, it was evident that the glutathione-microspheres with additional surfactant were more stable than glutathione with surfactant, but without microspheres. Similarly, the glutathione-microspheres with additional surfactant were more stable than the glutathione without surfactant. The in vivo effectivity showed lipophilic glutathione microspheres were able to decrease MMP-1 expression in the dermis tissue of mice. Conclusion: The results of freeze-dried glutathione-loaded alginate microspheres with surfactant with a HLB value equal to 7 can be utilized as potential glutathione delivery systems.

[Immunohistochemical study of the specific features of expression of matrix metalloproteinases 1, 9 in the photoaged skin, the foci of actinic keratosis and basal cell carcinoma]

Matrix metalloproteinases (MMPs) mediate the degradation of all types of collagens and other extracellular matrix components (elastin, proteoglycans, and laminin), their synthesis and accumulation play a key role in the hydrolysis of basement membrane. MMPs are involved in a wide range of proteolytic processes in the presence of different physiological and pathological changes, including inflammation, wound healing, angiogenesis, and carcinogenesis.

AIM

to study the specific features of MMP-1 and MMP-9 expression in different stages of skin photoaging, in the foci of actinic keratosis and basal cell carcinoma by immunohistochemical examination.

MATERIAL AND METHODS

12 samples of the healthy skin (6 samples of the eyelid skin with Glogau grade II photoaging; 6 ones of eyelid skin with Glogau grades III-IV photoaging) and biopsies from 8 foci of actinic keratosis and from 8 ones of basal cell carcinoma were examined. A positive reaction to MMPs was shown as different brown staining intensity in the cytoplasm of keratinocytes/tumor cells.

RESULTS

MMP-1 and MMP-9 expression was recorded in 67% of the histological specimens of the Glogau grade III photoaged skin and in 100% of those of Glogau grade IV. In the foci of actinic keratosis, the expression of MMP-1 was observed in 62.5% of cases and that of MMP-9 was seen in 87.5%. In basal cell carcinoma, the expression of MMP-1 and MMP-9 was detected in all investigated samples.

CONCLUSION

The immunomorphological findings are indicative of the important role of the level of MMP-1 and MMP-9 expression that is associated with the degree of progression of skin photoaging processes. Minimal MMP-1 and MMP-9 expression was recorded even in grades III-IV photoaging and in the foci of actinic keratosis. Intense MMP-1 and MMP-9 expression was detected in malignant skin epithelial neoplasms as different clinicomorphological types of basal cell carcinoma.