Glucocorticoid insensitivity affects a subset of asthma patients, yet its mechanism is unclear. Given the key role of airway epithelium in asthma, this study hypothesized that glucocorticoids may impair this barrier. We examined whether glucocorticoid-induced autophagy-associated apoptosis contributes to reduced treatment efficacy. Using an ovalbumin-induced asthma model in BALB/c mice and 16HBE human bronchial epithelial cells treated with dexamethasone and/or autophagy inhibitor EACC (C13H11N3O6S2), we assessed cell viability and apoptosis via CCK-8 and TUNEL assays, respectively. Apoptosis and autophagy markers were analyzed by quantitative polymerase chain reaction (PCR) and western blot. Dexamethasone alleviated airway inflammation but worsened epithelial integrity in asthmatic mice. It failed to downregulate pro-apoptotic factors while reducing anti-apoptotic factors both in vivo and in vitro. Dexamethasone decreased 16HBE cell viability and increased apoptosis. Mechanistically, dexamethasone upregulated autophagy markers and suppressed anti-autophagy factors in mouse lungs and cells, concurrently reducing the phosphorylation of negative regulators of autophagy. Importantly, the autophagy inhibitor EACC enhanced cell viability and attenuated dexamethasone-induced apoptotic signaling in 16HBE cells. These findings suggest glucocorticoids may compromise the airway epithelial barrier via autophagy-associated apoptosis in vitro and in vivo, indicating autophagy inhibition as a potential hypothesis for future therapeutic exploration for glucocorticoid-insensitive asthma.
ABSTRACT Among preterm infants, bronchopulmonary dysplasia (BPD) is the most prevalent chronic pulmonary disorder. Its pathogenesis involves a complex interplay between prenatal inflammatory exposure and abnormal immune activation. Neutrophil extracellular traps (NETs) are mediators of tissue damage, but whether they bridge intrauterine inflammation and the subsequent development of BPD is not yet clear. We used a prenatal lipopolysaccharide (LPS)‐exposed rat model to ask two questions: first, whether excessive NETs drive BPD pathogenesis, and second, whether human umbilical cord mesenchymal stem cell‐derived microvesicles (hUCMSC‐MVs) can alleviate lung injury by inhibiting this process. We established a BPD model in preterm rats via prenatal LPS exposure and assessed lung morphometry, neutrophil infiltration, and NETs markers. We then compared the therapeutic effects of hUCMSC‐MVs with NET extrusion (NETosis) inhibitors in vivo and also examined direct neutrophil effects in vitro. Prenatal LPS exposure led to significantly elevated NET markers in both lung tissue and circulation, which correlated with severe alveolar simplification. Neutrophils in this model exhibited a “primed” phenotype with enhanced potential for NETs release. In vivo, hUCMSC‐MVs suppressed NET formation, attenuated neutrophilic inflammation, and restored alveolar structure, matching the efficacy of conventional NETosis inhibitors. In vitro, they were internalized by neutrophils and abrogated LPS‐induced NETosis. These findings point to excessive NETosis as a key mechanistic link between prenatal inflammation and postnatal lung impairment. hUCMSC‐MVs directly inhibit this pathological process and alleviate BPD‐like lung injury. This work advances the mechanistic understanding of BPD and supports hUCMSC‐MVs as a promising cell‐free therapeutic candidate.
ABSTRACT Tubular epithelial dedifferentiation and loss of polarity are early pathological events in obstructive nephropathy and critically contribute to progressive renal fibrosis. Human umbilical cord mesenchymal stem cell–derived exosomes (HucMSC‐Exos) have shown therapeutic potential for kidney injury, yet the mechanisms by which they preserve epithelial identity remain unclear. Mafb, a transcription factor essential for renal epithelial differentiation, has been implicated in epithelial homeostasis, but its role in adult obstructive injury and its regulation by exosomes are unknown. Here, a unilateral ureteral obstruction (UUO) mouse model was used to evaluate early tubular injury and the effects of HucMSC‐Exos. UUO induced marked epithelial damage characterized by decreased E‐cadherin, increased vimentin and α‐smooth muscle actin (α‐SMA) expression, and disruption of epithelial polarity, whereas HucMSC‐Exo administration significantly ameliorated these alterations. Mafb expression was profoundly downregulated in UUO kidneys but was effectively restored following exosome treatment. In vitro, Mafb knockdown in Human renal proximal tubular epithelial (HK‐2) cells markedly aggravated TGF‐β1–induced dedifferentiation, confirming its protective role in epithelial integrity. Analysis of Mafb−/− embryonic kidneys demonstrated severe developmental defects and loss of polarity markers, highlighting the essential function of Mafb in renal epithelium. Importantly, HucMSC‐Exos rescued epithelial marker expression even in Mafb‐silenced cells, suggesting both Mafb‐dependent and independent mechanisms. These findings identify Mafb as a key regulator of tubular epithelial homeostasis and reveal that HucMSC‐Exos attenuate early renal injury partly through Mafb restoration.
ABSTRACT The optimal dose for ultrasound‐guided axillary brachial plexus block (ABPB) in children remains poorly defined. This study aimed to find the median effective volume (EV50) of ropivacaine (0.2%) for ABPB in children aged 6–10 years. A prospective, double‐blind, dose‐finding trial using the Dixon up‐and‐down method was conducted. Pediatric patients (aged 6–10 years, ASA I–II) undergoing unilateral elbow or below‐elbow surgery were enrolled. Ultrasound‐guided ABPB was performed using a dual‐injection technique with supplemental musculocutaneous nerve blockade. The initial volume of ropivacaine (0.2%) was 0.5 mL/kg, adjusted by 0.05 mL/kg based on the previous patient's response. The study continued until seven inflection points were observed from failure to success. EV50 and EV95 (95% effective volume) were calculated using isotonic regression and bootstrapping, with 95% confidence intervals (CIs). Patient demographics, postoperative pain scores, and adverse events were monitored. Twenty‐nine patients were enrolled. The EV50 was 0.350 mL/kg (95% CI: 0.197–0.362 mL/kg), and the EV95 was 0.395 mL/kg (95% CI: 0.385–0.396 mL/kg). No adverse events were observed during the perioperative period. This study provides evidence‐based dosing parameters for 0.2% ropivacaine in pediatric ABPB, aiding clinicians in optimizing efficacy and safety. The findings support age‐specific precision in pediatric regional anesthesia.
Hypospadias is among the most frequent congenital malformations of the male genitalia. The expression of V-maf musculoaponeurotic fibrosarcoma oncogene homolog B (MAFB), a transcription factor within the androgen signaling pathway, is closely correlated with the etiology of this condition. From an epigenetic perspective, this study investigated the role of microRNA-130a-3p (miR-130a-3p) in regulating MAFB during hypospadias pathogenesis. Clinical foreskin samples from hypospadias children and the dioctyl phthalate (DEHP)-induced mouse genital tubercle tissues were analyzed. The expression levels of miR-130a-3p and MAFB were detected by qRT-PCR and western blot. In vitro, miR-130a-3p was modulated in HS68 cells; CCK-8, scratch assay, western blot, flow cytometry, and dual-luciferase assay were used to assess its effects and targeting of MAFB. Our study demonstrated that miR-130a-3p targeted and suppressed MAFB expression. This suppression inhibited cellular proliferation and migration and reduced Vimentin mRNA expression. Cell cycle distribution was disrupted, marked by Gap 1 phase increase and Synthesis phase reduction, and the cell apoptosis rate increased. Cyclin-dependent kinase 2 (CDK2), Cyclin E1, and Proliferating Cell Nuclear Antigen (PCNA) were downregulated. miR-130a-3p targets and inhibits MAFB expression, disrupting the normal processes of cell proliferation, migration, cell apoptosis, and cell cycle progression, ultimately leading to the development of hypospadias.
