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Corneal ulcers, characterized by severe inflammation of the cornea, can lead to serious, debilitating complications and may be vision-threatening for horses. In this study, we aimed to investigate the role of endoplasmic reticulum (ER) stress in corneal stem progenitor cell (CSSC) dysfunction and explore the potential of equine adipose-derived stromal stem cell (ASC)-derived extracellular vesicles (EVs) to improve corneal wound healing. We showed that CSSCs expressed high levels of CD44, CD45, and CD90 surface markers, indicating their stemness. Supplementation of the ER-stress-inducer tunicamycin to CSSCs resulted in reduced proliferative and migratory potential, accumulation of endoplasmic reticulum (ER)-stressed cells in the G0/G1 phase of the cell cycle, increased expression of proinflammatory genes, induced oxidative stress and sustained ER stress, and unfolded protein response (UPR). Importantly, treatment with EVs increased the proliferative activity and number of cells in the G2/Mitosis phase, enhanced migratory ability, suppressed the overexpression of proinflammatory cytokines, and upregulated the anti-inflammatory miRNA-146a-5p, compared to control and/or ER-stressed cells. Additionally, EVs lowered the expression of ER-stress master regulators and effectors (PERK, IRE1, ATF6, and XBP1), increased the number of mitochondria, and reduced the expression of Fis-1 and Parkin, thereby promoting metabolic homeostasis and protecting against apoptosis in equine CSSCs. Our findings demonstrate that MSCs-derived EVs represent an innovative and promising therapeutic strategy for the transfer of bioactive mediators which regulate various cellular and molecular signaling pathways.
RESUMO
BACKGROUND: Personality traits may also be associated with preference for a particular specialty. However, little is known about the relationship between the surgical career preferences of medical students and their temperament traits. PURPOSES: The aim of the study was to explore the relationship between surgical or nonsurgical specialties and temperament in 6th-year medical students. METHODS: The study included 409 students (283 women, 126 men) of the 6th year at the Medical University of Lodz. The subjects fulfilled a career preference and demographic questionnaire as well as the Formal Characteristics of Behaviour-Temperament Inventory by Zawadzki and Stelau. RESULTS: The surgical specialty was preferred by 30.1% of the students and by 64.5% of the nonsurgical; 5.4% were undecided. The specialty preference of the medical students was associated with temperament traits. An analysis of variance showed differences in Emotional Reactivity, F(1, 380)=3.888, p=049, η2=01; Endurance, F(1, 380)=10.973, p=001, η2=028; and Briskness, F(1, 380)=10.252, p=001, η2=026. Students preferring surgical specialty scored significantly higher on Endurance (M=11.21, SD=4.8) and Briskness (M=16.54, SD=2.82) scales than students choosing a nonsurgical specialty (M=9.12, SD=4.51) and (M=15.19, SD=3.21), respectively. Those preferring a surgical specialty scored lower on the Emotional Reactivity (M=8.91, SD=4.55) scale than students choosing nonsurgical specialty (M=10.53, SD=4.22). CONCLUSIONS: The findings suggest that certain temperament traits may be related to preference of surgical or nonsurgical specialties. This knowledge of temperament traits could be a useful tool in helping graduates choose a fulfilling career best suited to their psychological well-being and diagnosing work related issues in the medical profession.
