Extracellular vesicles from adipose-derived stem cells ameliorate ultraviolet B-induced skin photoaging by attenuating reactive oxygen species production and inflammation
STEM CELL RESEARCH & THERAPY
Authors: Xu, Peng; Xin, Yu; Zhang, Zheng; Zou, Xiangyu; Xue, Ke; Zhang, Huizhong; Zhang, Wenjie; Liu, Kai
Abstract
Background: Large numbers of adipose-derived stem cells (ADSCs) are easily obtained and have been demonstrated to protect against ultraviolet B (UVB)-induced skin photoaging. Extracellular vesicles (EVs) exhibit some of the same effects as the cells from which they originate and have many advantages over stem cells. In particular, their application circumvents many safety concerns associated with cell therapy. Thus, as a cell-free agent, adipose-derived stem cell extracellular vesides (ADSC-EVs) have anti-photoaging potential. However, the protective effects of ADSC-EVs in skin photoaging remain uncertain. Methods: To investigate the effect of ADSC-EVs on mice with UVB-induced photoaging, 150 mu g and 300 mu g ADSC-EVs were subcutaneously injected weekly into photoaging mice for 8 weeks. The protective effect was evaluated by gross assessment and hematoxylin and eosin, Masson's trichrome, and beta-galactosidase staining. Proliferating cell nuclear antigen, CD68, and dihydroethidium staining were performed to evaluate cell proliferation, inflammation infiltration, and reactive oxygen species (ROS) production, respectively. In vitro, 100 mu g/mL and 200 mu g/mL ADSC-EVs were used to treat photoaging fibroblasts (FBs). beta-galactosidase staining and collagen 1 and matrix metalloproteinase 3 (MMP-3) expression were analyzed to evaluate FB senescence. To explain the protective mechanism of ADSC-EVs, their role in regulating ROS production, antioxidant enzyme expression, cell cycle arrest, and inflammation was evaluated. Results: In vivo, we showed that ADSC-EVs decreased skin wrinkles in mice with UVB-induced photoaging, while promoting epidermal cell proliferation and attenuating macrophage infiltration and ROS production. In vitro, we showed that ADSC-EVs increased FB activity and protected FBs from UVB-induced senescence, attenuated raw 264.7 cell differentiation from M0 to M1 macrophages, reduced intracellular ROS production, promoted antioxidant enzyme expression, and rescued FBs from cell cycle arrest. Conclusion: The anti-photoaging effect of ADSC-EVs was attributed to their ability to attenuate ROS production and the inflammatory response, which are key factors in MMP activation and collagen degradation.
Macrophages of the subcutaneous and omental fatty tissue in obese patients: Immunohistochemical phenotyping of M2 subtypes in relation to type 2 diabetes
BIOMEDICAL PAPERS-OLOMOUC
Authors: Chylikova, Jaroslava; Dvorackova, Jana; Cizkova, Katerina; Lacey, Helena; Kamarad, Vojtech
Abstract
Background and Aims. Macrophages are linked to the initiation of the chronic inflammation believed to underlie the changes taking place in the white fatty tissue of obese people. Both the number of macrophages, but their functional status, play an important role in the development of inflammation. Classically, macrophages are divided into two types: pro-inflammatory (M1) and anti-inflammatory (M2) types, and based on current immunological studies, further views on the functional distribution of macrophages are suggested. In this study, we evaluated the M1 and M2 macrophages ratio in obese subjects with, or without diabetes. To identify all macrophages, we used CD68 expression, while CD204 expression is typically used for the M2 macrophage. Materials and Methods. During bariatric surgery, carried out in obese people with and without type 2 diabetes (T2D), we obtained subcutaneous adipose tissue from the navel and omental adipose tissue. We also obtained the same tissue from people with a physiological range of BMI from a judicial autopsy. Applying immunohistochemical staining anti-CD68 and anti-CD204, we carried out a quantitative evaluation of the number of macrophages. Results. We found CD68+ and CD204+ positive macrophages in perivascular spaces and between fat cells, both isolated and in larger infiltrates. They were also present in so-called "crown-like structures" (CLS) around dying adipocytes. Quantitative analysis showed an increased number of macrophages in all obese patients compared to the control group of non-obese, individuals without T2D. The most striking observation was the macrophage increase in the visceral fatty tissue of diabetics. The number of CD68 and CD204 positive macrophages was statistically significantly smaller in patients without T2D. Conclusion. We demonstrated a significantly greater number of macrophages in visceral adipose tissue, especially in patients with T2D. Our results also show a positive correlation between the presence of T2D and the total number of macrophages; a significantly greater number of macrophages were found in visceral adipose tissue, especially in patients with T2D.