Int J Med Sci
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Background: Acute lung injuries (ALI) cause disruption of the alveolar-capillary barrier and is the leading cause of death in critically ill patients. This study tested the hypothesis that the administration of freshly isolated viable allogeneic mitochondria can prevent alveolar-capillary barrier injuries at the endothelial level, as mitochondrial dysfunction of the pulmonary endothelium is a critical aspect of ALI progression. Methods: ALI was induced by intratracheal lipopolysaccharide instillation (LPS, 1mg/kg) in anesthetized rats. ⋯ In addition, relaxation responses to acetylcholine and eNOS expression were potentiated in injured pulmonary arteries and inflammatory cells infiltration into lung tissue was reduced following mitochondrial transplantation. Conclusions: Transplantation of viable mitochondria protects the integrity of endothelial lining of the alveolar-capillary barrier, thereby improving gas exchange during the acute stages of endotoxin-induced ALI. However, the long-term effects of mitochondrial transplantation on pulmonary function recovery after ALI requires further investigation.
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The injury of Schwann cells is an important pathological feature of peripheral neuropathy. However, the explicit molecular mechanism and blocking method remains to be explored. In this study, we identified an pivotal executor of necroptosis-RIPK1, performed an unique function in response to oxidative stress-induced injury in Rat Schwann cells. ⋯ While administration of Necrostatin-1 (Nec-1) failed to influence the levels of ROS and mitochondrial membrane potential, revealing that RIPK1 served as the down-stream regulators of ROS. Lastly, pharmacological inhibition of RIPK1 by Nec-1 attenuated the levels of necroptosis, increased proliferation, as indicated by Annexin V/PI evaluation, CCK-8 detection, TEM scanning and EdU staining. Our results indicate a previous un-recognized post-translational change of RIPK1 in response to oxidative stress in Schwann cells.
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Mammalian cardiomyocytes (CMs) maintain a low capacity for self-renewal in adulthood, therefore the induction of CMs cycle re-entry is an important approach to promote myocardial repair after injury. Recently, photobiomodulation (PBM) has been used to manipulate physiological activities of various tissues and organs by non-invasive means. Here, we demonstrate that conditioned PBM using light-emitting diodes with a wavelength of 630 nm (LED-Red) was capable of promoting the proliferation of neonatal CMs. ⋯ Moreover, GADD45g siRNA reversed the positive effect of LED-Red on the proliferation of neonatal CMs. Taken together, conditioned LED-Red irradiation increased miR-877-3p expression and promoted the proliferation of neonatal CMs by targeting GADD45g. This finding provides a new insight into the role of LED-Red irradiation in neonatal CMs biology and suggests its potential application in myocardial injury repair.
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Background: We previously found that intermediate conductance Ca2+-activated K+ channel (SK4) might be an important target in atrial fibrillation (AF). Objective: To investigate the role of SK4 in AF maintenance. Methods: Twenty beagles were randomly assigned to the sham group (n=6), pacing group (n=7), and pacing+TRAM-34 group (n=7). ⋯ Compared with the sham group, the expression of SK4 in atria was higher in the pacing group, which was associated with an increased number of myofibroblasts and levels of extracellular matrix in atrium (all P<0.05), and this effect was reversed by TRAM-34 treatment (all P<0.05). In atrial fibroblasts, the increased expression of SK4 induced by angiotensin II stimulation or Ad-SK4 transfection contributed to higher levels of P38, ERK1/2 and their downstream factors c-Jun and c-Fos, leading to the increased expression of α-SMA (all P<0.05), and all these increases were markedly reduced by TRAM-34 treatment. Conclusion: SK4 blockade suppressed AF by attenuating cardiac fibroblast activity and atrial fibrosis, which was realized through not only a decrease in fibrogenic factors but also inhibition of fibrotic signaling pathways.
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Background: Kartogenin is a heterocyclic compound able to promote the proliferation, migration, and differentiation of various cell types and induce cartilage-like tissue regeneration. However, the role of kartogenin in hair follicles (HFs), remains unknown. We therefore investigated the effects of kartogenin on the regulation of hair growth and hair growth cycle transition. ⋯ Results: Kartogenin enhanced ORSC proliferation and migration function in a dose-dependent manner, and downregulated the expression of TGF-β2/Smad signaling molecules in vitro. Injection of kartogenin delayed catagen phase and increased regenerated hair length in mice in vivo. Conclusions: Kartogenin modulates HF growth and regulates the hair cycle and the TGF-β2/Smad signaling pathway, providing a potential new approach for the treatment of hair loss.