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The photosynthetic strain Z of Euglena gracilis is more susceptible to cadmium chloride (Cd) than the non-photosynthetic strain SMZ. We investigated the correlation of intracellular reactive oxygen species (ROS) levels with Cd-induced cellular damage. Flow cytometry with dihydrorhodamine 123 showed that strain Z generated higher levels of ROS, probably H2O2 and/or ONOO−, than strain SMZ, and that this difference between the two strains became more pronounced with increasing Cd dose. The levels of ROS increased at cytotoxic concentrations of Cd, at over 10 μM Cd for Z and 50 μM Cd for SMZ. These results show an association of Cd cytotoxicity with ROS generation. Considering that strain SMZ is non-photosynthetic, the higher levels of ROS in strain Z might be due to blockage of photosynthetic electron flow by Cd. Using terminal deoxyribonucleotidyl transferase-mediated dUTP nick end-labeling analysis in combination with 4′,6-diamidino-2-phenylindole, dihydrochloride staining, we observed DNA breaks in the mitochondria of both strains after Cd exposure. The results suggest that the mitochondrion is the primary target organelle of Cd in E. gracilis cells. [Copyright &y& Elsevier]

The effective use of human-derived cells that are difficult to freeze, such as parenchymal cells and differentiated cells from stem cells, is crucial. A stable supply of damage-sensitive cells, such as differentiated neuronal cells, neurons, and glial cells can contribute considerably to cell therapy. We developed a serum-free freezing solution that is effective for the cryopreservation of differentiated neuronal cells. The quality of the differentiated and undifferentiated SK-N-SH cells was determined based on cell viability, live-cell recovery rate, and morphology of cultured cells, to assess the efficacy of the freezing solutions. The viability and recovery rate of the differentiated SK-N-SH neuronal cells were reduced by approximately 1.5-folds compared to that of the undifferentiated SK-N-SH cells. The viability and recovery rate of the differentiated SK-N-SH cells were remarkably different between the freezing solutions containing 10% DMSO and that containing 10% glycerol. Cryoprotectants such as fetal bovine serum (FBS), antifreeze proteins (sericin), and sugars (maltose), are essential for protecting against freeze damage in differentiated neuronal cells and parenchymal cells. Serum-free alternatives (sericin and maltose) could increase safety during cell transplantation and regenerative medicine. Considering these, we propose an effective freezing solution for the cryopreservation of neuronal cells., Competing Interests: The authors declare no conflict of interest., (© 2022 The Japanese Society for Regenerative Medicine. Production and hosting by Elsevier B.V.)

Introduction: The development of cancer generally occurs as a result of various deregulated molecular mechanisms affecting the genes that can control normal cellular growth. Signal transducer and activator of transcription 3 (STAT3) pathway, once aberrantly activated can promote carcinogenesis by regulating the transcription of a number of oncogenic genes., Objectives: Here, we evaluated the impact of fangchinoline (FCN) to attenuate tumor growth and survival through modulation of oncogenic STAT3 signaling pathway using diverse tumor cell lines and a xenograft mouse model., Methods: To evaluate the action of FCN on STAT3 cascade, protein levels were analyzed by Western blot analysis and electrophoretic mobility shift assay (EMSA). Translocation of STAT3 was detected by immunocytochemistry. Thereafter, FCN-induced ROS was measured by GSH/GSSG assay and H2DCF-DA. FCN-induced apoptosis was analyzed using Western blot analysis and flow cytometry for various assays. Finally, anti-cancer effects of FCN in vivo was evaluated in a myeloma model., Results: We noted that FCN abrogated protein expression levels of STAT3 and upstream signals (JAK1/2 and Src). In addition, FCN also attenuated DNA binding ability of STAT3 and its translocation into the nucleus. It altered the levels of upstream signaling proteins, increased SHP-1 levels, and induced substantial apoptosis in U266 cells. FCN also promoted an increased production of reactive oxygen species (ROS) and altered GSSG/GSH ratio in tumor cells. Moreover, FCN effectively abrogated tumor progression and STAT3 activation in a preclinical myeloma model., Conclusion: Overall, this study suggests that FCN may have a tremendous potential to alter abnormal STAT3 activation and induce cell death in malignant cells along with causing the suppression of pathogenesis and growth of cancer through a pro-oxidant dependent molecular mechanism., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2021 The Authors. Published by Elsevier B.V. on behalf of Cairo University.)

Background & Aims: Aberrations in the esophageal proliferation-differentiation gradient are histologic hallmarks in eosinophilic esophagitis (EoE) and gastroesophageal reflux disease. A reliable protocol to grow 3-dimensional (3D) esophageal organoids is needed to study esophageal epithelial homeostasis under physiological and pathologic conditions., Methods: We modified keratinocyte-serum free medium to grow 3D organoids from endoscopic esophageal biopsies, immortalized human esophageal epithelial cells, and murine esophagi. Morphologic and functional characterization of 3D organoids was performed following genetic and pharmacologic modifications or exposure to EoE-relevant cytokines. The Notch pathway was evaluated by transfection assays and by gene expression analyses in vitro and in biopsies., Results: Both murine and human esophageal 3D organoids displayed an explicit proliferation-differentiation gradient. Notch inhibition accumulated undifferentiated basal keratinocytes with deregulated squamous cell differentiation in organoids. EoE patient-derived 3D organoids displayed normal epithelial structure ex vivo in the absence of the EoE inflammatory milieu. Stimulation of esophageal 3D organoids with EoE-relevant cytokines resulted in a phenocopy of Notch inhibition in organoid 3D structures with recapitulation of reactive epithelial changes in EoE biopsies, where Notch3 expression was significantly decreased in EoE compared with control subjects., Conclusions: Esophageal 3D organoids serve as a novel platform to investigate regulatory mechanisms in squamous epithelial homeostasis in the context of EoE and other diseases. Notch-mediated squamous cell differentiation is suppressed by cytokines known to be involved in EoE, suggesting that this may contribute to epithelial phenotypes associated with disease. Genetic and pharmacologic manipulations establish proof of concept for the utility of organoids for future studies and personalized medicine in EoE and other esophageal diseases.