ABSTRACT
Thyroxine receptor beta (TRß) is a ligand-dependent nuclear receptor that participates in regulating multiple biological processes, particularly playing an important role in lipid metabolism regulation. TRß is currently a popular therapeutic target for nonalcoholic steatohepatitis (NASH), while no drugs have been approved to treat this disease. MGL-3196 (Resmetirom) is the first TRß agonist that has succeeded in phase III clinical trials for the treatment of NASH; therefore, studying its molecular mechanism of action is of great significance. In this study, we employed molecular dynamic simulation to investigate the interaction mode between MGL-3196 and TRß at the all-atom level. More importantly, by comparing the binding patterns of MGL-3196 in several prevalent TRß mutants, it was identified that the mutations R243Q and H435R located, respectively, around and within the ligand-binding pocket of TRß cause TRß to be insensitive to MGL-3196. This indicates that patients with NASH carrying these two mutations may exhibit resistance to the medication of MGL-3196, thereby highlighting the potential impact of TRß mutations on TRß-targeted treatment of NASH and beyond.
ABSTRACT
The objective of this study was to assess the relationship of ACS with neonatal outcomes among very preterm infants born to mothers with clinical chorioamnionitis in China. This was a multicenter retrospective cohort study. Study participants included infants born at <32 weeks' gestation with clinical chorioamnionitis and registered in the Chinese Neonatal Network from 1 January 2019 to 31 December 2020. Infants were divided into two groups: any amount of ACS or no administration of ACS. Multivariable generalized linear models using generalized estimating equations were used to assess the association between ACS and neonatal outcomes among the study population. We identified 2193 infants eligible for this study; 1966 (89.6%) infants had received ACS therapy, and 227 (10.4%) had not received any ACS therapy. Among very preterm infants born to mothers with clinical chorioamnionitis, any ACS usage was significantly associated with decreased risks of early death (aRR 0.56, 95% CI 0.32, 0.99) and severe ROP (aRR 0.51, 95% CI 0.28, 0.93) after adjustment for maternal hypertension, gestational age at birth, Caesarean section, being inborn, and administration of systemic antibiotics to the mother within 24 h before birth. In addition, out of the 2193 infants, the placentas of 1931 infants underwent pathological examination with recorded results. Subsequently, 1490 of these cases (77.2%) were diagnosed with histological chorioamnionitis. In 1490 cases of histologic chorioamnionitis, any ACS usage was significantly related to decreased risks of overall mortality (aRR 0.52, 95% CI 0.31, 0.87), severe ROP (aRR 0.47, 95% CI 0.25, 0.97), and respiratory distress syndrome (aRR 0.52, 95% CI 0.31, 0.87). We concluded that any ACS was associated with reduced risks for neonatal early death and severe ROP among very preterm infants born to mothers with clinical chorioamnionitis.
ABSTRACT
Primary carnitine deficiency (PCD) caused by pathogenic variants in the solute carrier family 22 member 5 (SLC22A5) gene is a rare autosomal recessive disease that results in defective fatty acid oxidation. PCD can be detected through tandem mass spectrometry (MS/MS), but transplacental transport of free carnitine from mothers may cause false negatives or positives during newborn screening (NBS). This study aimed to analyze the genetic characteristics of SLC22A5 and estimate the prevalence of PCD in the Chinese population, providing useful information for NBS and genetic counseling. We manually curated SLC22A5 pathogenic or likely pathogenic (P/LP) variants according to the American College of Medical Genetics and Genomics (ACMG) guidelines and identified 128 P/LP variants. Based on the China Neonatal Genomes Project (CNGP), the estimated PCD prevalence was 1:17,456, which was higher than that in other populations. The genotype-phenotype association analysis showed that patients carrying homozygous c.760C>T and c.844C>T were more likely to present cardiomyopathy, whereas those carrying homozygous c.1400C>G were more likely to be asymptomatic (all p-values < 0.05). We found that there was no significant difference in initial C0 concentrations between patients and carriers, but there was a significant difference in the second-tier screening of C0 concentration between them (p-value < 0.05). We established a cost-effective variant panel containing 10 high-frequency sites and developed a screening algorithm incorporating gene panels with MS/MS, which could rescue one more patient who was undetected from MS/MS. In conclusion, the prevalence of PCD in the Chinese population is relatively high. The combination of conventional NBS with genetic sequencing is suggested for early diagnosis of PCD.