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Skin wound repair is a multistage process involving multiple cellular and molecular interactions, which modulate the cell behaviors and dynamic remodeling of extracellular matrices to maximize regeneration and repair. Consequently, abnormalities in cell functions or pathways inevitably give rise to side effects, such as dysregulated inflammation, hyperplasia of nonmigratory epithelial cells, and lack of response to growth factors, which impedes angiogenesis and fibrosis. These issues may cause delayed wound healing or even non‐healing states. Current clinical therapeutic approaches are predominantly dedicated to preventing infections and alleviating topical symptoms rather than addressing the modulation of wound microenvironments to achieve targeted outcomes. Bioactive materials, relying on their chemical, physical, and biological properties or as carriers of bioactive substances, can affect wound microenvironments and promote wound healing at the molecular level. By addressing the mechanisms of wound healing from the perspective of cell behaviors, this review discusses how bioactive materials modulate the microenvironments and cell behaviors within the wounds during the stages of hemostasis, anti‐inflammation, tissue regeneration and deposition, and matrix remodeling. A deeper understanding of cell behaviors during wound healing is bound to promote the development of more targeted and efficient bioactive materials for clinical applications. [ABSTRACT FROM AUTHOR]

New Findings What is the central question of this study? The present study investigated the relationship between H2S and NO in regulation of gastric fundus tension., What is the main finding and its importance? Endogenous or exogenous H2S and NO have opposite effects on fundus tension, and H2S-induced gastric fundus tension enhancements are mediated by inhibition of NO generation through the phosphoinositide 3-kinase/Akt pathway. These results are very important in exploring the mechanism of physiological accommodation and accommodation disorder., Hydrogen sulphide (H2S) is considered a new gasotransmitter, along with NO and CO. It was recently confirmed that H2S and NO play important roles in the regulation of gastrointestinal smooth muscle tension. The present study was designed to elucidate the interactions between H2S and NO with respect to the regulation of gastric fundus smooth muscle tension using Western blotting, physiological and electrochemical techniques. Real-time H2S and NO generation was detected in gastric smooth muscle tissue. NaHS, an H2S donor, enhanced fundus smooth muscle tension, whereas SNP, an NO donor, decreased fundus smooth muscle tension in a dose-dependent manner. NaHS-induced increases in fundus smooth muscle tension were suppressed by l-NAME, an NO synthase inhibitor. Aminooxyacetic acid (AOAA), a cystathionine β-synthase inhibitor, exerted inhibitory effects on fundus smooth muscle tension; these effects were also suppressed by l-NAME. Real-time NO generation was significantly potentiated by AOAA. Endothelial nitric oxide synthase (eNOS) phosphorylation at serine 1177 and Akt phosphorylation at serine 308 and threonine 473 were significantly inhibited by NaHS. LY294002, a phosphoinositide 3-kinase inhibitor, blocked these NaHS-mediated effects. However, eNOS phosphorylation at serine 1177 and Akt phosphorylation at serine 308 and threonine 473 were significantly potentiated by AOAA. Cystathionine β-synthase siRNA interference significantly increased eNOS phosphorylation at serine 1177 and Akt phosphorylation at serine 308 and threonine 473. Cystathionine β-synthase siRNA interference also increased total eNOS protein expression levels but did not significantly change total Akt kinase protein expression levels. These results suggest that H2S-induced enhancement of gastric fundus tension is mediated by inhibition of NO generation through the phosphoinositide 3-kinase/Akt pathway. [ABSTRACT FROM AUTHOR]

Epidermal growth factor (EGF) plays an important role in epithelial cell proliferation and apoptosis. Our recent studies found that EGF-attenuated tumor necrosis factor-α induced HaCaT keratinocyte apoptosis, and this effect was accompanied by up-regulation of the expression of peroxisome proliferator-activated receptor β (PPARβ). However, little is known about whether PPARβ is functionally involved in the inhibition of keratinocyte apoptosis by EGF. Here, we showed that EGF up-regulated the DNA-binding and transcriptional regulation activities of PPARβ. Antisense phosphorothioate oligonucleotides against PPARβ markedly inhibited de novo synthesis of PPARβ and attenuated the protective effect of EGF on tumor necrosis factor-α–induced apoptosis. L165041, a specific PPARβ ligand, significantly enhanced the transcriptional regulation activity of PPARβ and increased the protective effect of EGF. These results suggest a molecular mechanism by which EGF protects HaCaT keratinocytes against apoptosis in a PPARβ-dependent manner. [ABSTRACT FROM AUTHOR]