Background: Adiponectin and resistin are typically secreted by the adipose tissue and are abnormally expressed in obesity. However, the underlying influential factors and mechanisms are to be elucidated. It is well known that the expression of genes is regulated by epigenetics while gut microbiota participates in epigenetic processes through its metabolites such as folate, biotin, and short-chain fatty acids (SCFAs). Therefore, we supposed that alteration of gut microbiota might affect the transcriptional expression of adiponectin and resistin through epigenetic regulation in obesity. Methods: C57BL/6J mice were fed either a high-fat diet (34.9% fat by wt., 60% kcal) or a normal-fat diet (4.3% fat by wt., 10% kcal) for 16 weeks, with ampicillin and neomycin delivered via drinking water to interfere with gut microbiota development. Fecal microbiota was analyzed by 16S rRNA high-throughput sequencing. The mRNA expression levels of genes were measured by real-time quantitative RT-PCR. SCFA contents in feces were examined using gas chromatography. Results: Alteration of the gut microbiota induced by antibiotic use, characterized by a dramatic reduction of the phylum Firmicutes and Actinobacteria and an increase of Proteobacteria with reductions of genera including Lactobacillus, norank_f_Bacteroidales_S24-7_group, Alistipes, Desulfovibrio, Helicobacter, etc., and increases in Bacteroides, Enterobacter, Klebsiella, inhibited the body weight gain in mice fed the high-fat diet instead of the normal-fat diet. The mRNA expression of adiponectin and resistin was upregulated by antibiotic use in mice fed the high-fat diet, accompanied by increased expression of fat oxidation and thermogenesis-related genes (PPAR-α, Pgc-1α, and Atgl) in the fat and/or liver, whereas no change in the expression of adiponectin and resistin was found in mice fed the normal-fat diet. Furthermore, antibiotic use reduced DNA methylation fractions of the adiponectin and resistin promoters and downregulated the expression of DNA methyltransferase 1 and 3a (DNMT1 and DNMT3a) with the high-fat diet feeding. Conclusion: Alteration of gut microbiota induced by antibiotic use may affect the expression of adiponectin and resistin in mice fed the high-fat diet by modifying promoter DNA methylation, thus leading to increased fatty acid oxidation and less body weight gain.

Background: The expression of leptin is increased in obesity and inhibited by n-3 polyunsaturated fatty acids (n-3 PUFAs), but the underlying molecular mechanisms have not been firmly established. Methods: In this study, we investigated the effects of dietary n-3 PUFAs on the methylation of CpG islands in the promoter regions of the leptin, leptin-R and POMC genes, as well as the effects of n-3 PUFA status in early life on the modification of the promoters of these three genes. Male C57 BL/6J mice were fed a high-fat diet with one of four different fat types: sunflower oil (n-3 PUFA deficient), soy oil, fish oil, or a mixture of soy and fish oil (soy:fish oil = 1:1). Two low-fat diets with sunflower oil or soy oil served as controls. Female mice were fed two breeding diets, sunflower oil or a mixture of soy and fish oil (soy:fish oil = 1:1), during pregnancy and lactation to breed new pups. Results: Compared to mice fed the control diets, the expression of leptin in fat tissue and leptin-R and POMC in the hypothalamus was higher in the diet-induced obesity (DIO) mice, and the n-3 PUFAs in the diets reversed these elevated expression levels. The mean methylation levels of CpG sites in the promoter regions of the leptin and POMC genes showed no difference between the DIO and the control diet groups nor between the n-3 PUFA-containing and -deficient diet groups. For the CpG sites in the promoter regions of leptin-R, no methylation was found in any of the DIO or control groups. Feeding mice with the n-3 PUFA diet during pregnancy and lactation did not affect CpG methylation in the leptin or POMC promoters. Conclusions: Our findings indicate that promoter DNA methylation may not be related to the expression of leptin, leptin-R or its related hypothalamic satiety regulator POMC.

Introduction: Long-term decannulation outcomes after pediatric tracheostomy, particularly among children discharged from the pediatric intensive care unit (PICU), remain poorly described. This study aimed to describe the long-term decannulation outcomes and factors associated with delayed decannulation within 180 days after hospital discharge. Methods: We retrospectively reviewed children aged 29 days to 18 years who underwent first-time tracheostomy in the PICU of Beijing Children's Hospital between January 2016 and December 2020. Follow-up data were obtained from medical records and standardized telephone interviews through August 31, 2025. The cumulative decannulation rate was estimated using the Kaplan–Meier analysis. Factors associated with delayed decannulation were analyzed using Cox regression. The discriminative ability of the independently associated factors in combination was assessed using receiver operating characteristic (ROC) curve analysis. Results: Among 234 children who underwent tracheostomy, 121 survivors with complete follow-up data were included in the final analysis. The median age at tracheostomy was 60 months (IQR, 15–111 months), and 30 patients (24.8%) were aged ≤1 year. At least one post-tracheostomy complication occurred in 66 children (54.5%), with late complications occurring in 62 children (51.2%). During final follow-up, 106 patients (87.6%) achieved successful decannulation, with a median time to decannulation of 126 days (IQR, 68–332). Within 180 days after discharge, 62 children (51.2%) achieved successful decannulation. Multivariable Cox regression analysis showed that age ≤1 year, obstructive airway disease, and poor cough reflex were independently associated with delayed decannulation within 180 days. The combination of these factors showed good discriminatory ability for 180-day decannulation status (AUC, 0.854; 95% CI, 0.783–0.926). Conclusions: Prolonged tracheostomy dependence was common after PICU discharge, with approximately half of children remaining cannulated at 180 days. Infancy, obstructive airway disease, and poor cough reflex were independently associated with delayed decannulation. Ventilator dependence and late complications were also associated with delayed decannulation. These late complications included respiratory infections, tube-related events, swallowing or phonation disorders, granulation tissue formation, tracheocutaneous fistula, and tracheal stenosis or malacia. These findings highlight the importance of individualized airway assessment, effective secretion management, surveillance for late complications, and continued multidisciplinary follow-up after discharge.