No abstract

Mesenchymal stem cells (MSCs) have been suggested as a primary candidate for cell therapy applications because they have self-renewal and differentiation capabilities. Although they can be expanded in ex vivo system, clinical application of these cells is still limited because they survive poorly and undergo senescence or apoptosis when transplanted and exposed to environmental factors such as oxidative stress. Thus, reducing oxidative stress is expected to improve the efficacy of MSC therapy. The milk protein lactoferrin is a multifunctional iron-binding glycoprotein that plays various roles, including reduction of oxidative stress. Thus, we explored the effect of lactoferrin on oxidative stress-induced senescence and apoptosis of human MSCs (hMSCs). Measurement of reactive oxygen species (ROS) revealed that lactoferrin inhibited the production of hydrogen peroxide-induced intracellular ROS, suggesting lactoferrin as a good candidate as an antioxidant in hMSCs. Pretreatment of lactoferrin suppressed hydrogen peroxide-induced senescence of hMSCs. In addition, lactoferrin reduced hydrogen peroxide-induced apoptosis via inhibition of caspase-3 and Akt activation. These results demonstrate that lactoferrin can be a promising factor to protect hMSCs from oxidative stress-induced senescence and apoptosis, thus increasing the efficacy of MSC therapy.

Gecko proteins have long been used as anti-tumor agents in oriental medicine, without any scientific background. Although anti-tumor effects of Gecko proteins on several cancers were recently reported, their effect on bladder cancer has not been investigated. Thus, we explored the anti-tumor effect of Gecko proteins and its cellular mechanisms in human bladder cancer 5637 cells. Gecko proteins significantly reduced the viability of 5637 cells without any cytotoxic effect on normal cells. These proteins increased the Annexin-V staining and the amount of condensed chromatin, demonstrating that the Gecko proteinsinduced cell death was caused by apoptosis. Gecko proteins suppressed Akt activation, and the overexpression of constitutively active form of myristoylated Akt prevented Gecko proteins-induced death of 5637 cells. Furthermore, Gecko proteins activated caspase 9 and caspase 3/7. Taken together, our data demonstrated that Gecko proteins suppressed the Akt pathway and activated the intrinsic caspase pathway, leading to the apoptosis of bladder cancer cells. [BMB Reports 2015; 48(9): 531-536]

No abstract

In this study, we performed two-dimensional electrophoresis with protein extracts from lizard tails, and analyzed the protein expression profiles during the tissue regeneration to identify the dedifferentiation factor. As a result, we identified 18 protein spots among total of 292 spots, of which proteins were specifically expressed during blastema formation. We selected lactoferrin as a candidate because it is the mammalian homolog of leech-derived tryptase inhibitor, which showed the highest frequency among the 18 proteins. Lactoferrin was specifically expressed in various stem cell lines, and enhanced the efficiency of iPSC generation upto approximately 7-fold relative to the control. Furthermore, lactoferrin increased the efficiency by 2-fold without enforced expression of Klf4. These results suggest that lactoferrin may induce dedifferentiation, at least partly by increasing the expression of Klf4.

No abstract

This paper addresses photometric distortion problems of a compact 3D scanning sensor which is composed of a micro-size and inexpensive camera-projector system. Recently, many micro-size cameras and projectors are available. However, erroneous 3D scanning results may arise due to the poor and nonlinear photometric properties of the sensors. This paper solves two inherent photometric distortions of the sensors. First, the response functions of both the camera and projector are derived from the least squares solutions of passive and active calibration, respectively. Second, vignetting correction of the vision camera is done by using a conventional method, however the projector vignetting is corrected by using the planar homography between the image planes of the projector and camera, respectively. Experimental results show that the proposed technique enhances the linear properties of the phase patterns that are generated by the sensor.

It is well-known that some species of lizard have an exceptional ability known as caudal autotomy (voluntary self-amputation of the tail) as an anti-predation mechanism. After amputation occurs, they can regenerate their new tails in a few days. The new tail section is generally shorter than the original one and is composed of cartilage rather than vertebrae bone. In addition, the skin of the regenerated tail distinctly differs from its original appearance. We performed a proteomics analysis for extracts derived from regenerating lizard tail tissues after amputation and found that endoplasmin (ENPL) was the main factor among proteins up-regulated in expression during regeneration. Thus, we performed further experiments to determine whether ENPL could induce chondrogenesis of tonsil-derived mesenchymal stem cells (T-MSCs). In this study, we found that chondrogenic differentiation was associated with an increase of ENPL expression by ER stress. We also found that ENPL was involved in chondrogenic differentiation of T-MSCs by suppressing extracellular signal-regulated kinase (ERK) phosphorylation.