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Static, Low-Frequency, and Pulsed Magnetic Fields in Biological Systems
Published in James C. Lin, Electromagnetic Fields in Biological Systems, 2016
In contrast to the estimation of torque force induced by a uniform SMF, the intense inhomogeneous SMF acting on diamagnetic materials can generate a strong magnetic force. Qian et al. (2009) have developed a superconducting magnet platform with large-gradient high magnetic field (LG-HMF), which can produce three magnetic force fields of –1360, 0, and 1312 T2/m and three corresponding apparent gravity levels of 0, 1, and 2 g for diamagnetic materials. The authors investigated the effects of different magnetic force fields on osteoblast-like cell (MG-63 and MC3T3-E1) viability, microtubule actin cross-linking factor 1 (MACF1) expression, and MACF1’s association with cytoskeleton. Results showed that cell viability increased to different degrees after 24 hours of exposure to 0 or 1 g conditions, whereas it decreased by about 30% under 2 g conditions compared with the control conditions. An increase in MACF1 expression at the RNA or protein level was observed in osteoblast-like cells under the LG-HMF of –1360 T2/m (0 g) compared to that under 1312 T2/m (2 g). Under control conditions, anti-MACF1 staining was scattered in the cytoplasm and partially colocalized with actin filaments or microtubules in most osteoblast-like cells. Under 0 g conditions, MACF1 labeling was concentrated at the perinuclear region and colocalization was not apparent. The patterns of anti-MACF1 labeling on microtubules varied under LG-HMF environment. In conclusion, LG-HMF affects osteoblast-like cell viability, MACF1 distribution, MACF1 expression, and MACF1’s association with cytoskeleton.
Conditioned medium from the three-dimensional culture of human umbilical cord perivascular cells accelerate the migration and proliferation of human keratinocyte and fibroblast
Published in Journal of Biomaterials Science, Polymer Edition, 2018
Min Ho Kim, Wen Hao Wu, Jee Hyun Choi, Ji Hyun Kim, Seok-Ho Hong, Jin Hyun Jun, Yong Ko, Jong Hun Lee
Although a significant difference was not detected in the proliferation of HDFs, the PVC-conditioned medium obtained from a more physiological environment was more effective in the proliferation and migration tests of cell lines than PVC-CM-2D (Figures 3, 4), suggesting that the two systems have different protein profiles. This finding led to further analyses of PVC-CM using 2D electrophoresis and MALDI-TOF (Figure 5, Table 1). PVC-CM-3D contained higher amounts of type I collagen and myosin heavy chain than PVC-CM-2D. The collagen provides cells with environments that mimic the extracellular matrix (ECM) of human skin; ECM has been regarded as very important for cellular adhesion, proliferation, and migration. It is therefore believed that this protein affects the proliferation and migration of keratinocytes and fibroblasts. KIAA0465, N-RAP, and thioredoxin are exclusively expressed in PVC-CM-3D. KIAA0465, which is also called ‘MACF1’, is a member of a family of proteins that form bridges between different cytoskeletal elements. This protein facilitates actin-microtubule interactions at the cell periphery and couples the microtubule network to cellular junctions. Moreover, KIAA0465 is involved in the organization of the cytoskeleton [30], tissue repair [31], and vertebrate development [32]. N-RAP is a nebulin family member that acts as an organizing center for the initial recruitment and assembly of sarcomeric actin filaments and Z-discs [33]. Thioredoxins are proteins that act as antioxidants by facilitating the reduction of other proteins by cysteine thiol-disulfide exchange. Thioredoxins are found in nearly all known organisms and are essential for life in mammals [34]. Recently, Telorack et al. (2016) reported that a glutathione-Nrf2-thioredoxin cross-talk ensures keratinocyte survival and efficient wound repair [35]. These reports indicate that type I collagen, KIAA0465, N-RAP, and thioredoxin are involved not only in the proliferation, migration, and adhesion of human keratinocytes and fibroblasts, but also in the wound-healing process.