A compound heterozygous mutation of ERCC8 is responsible for a family with Cockayne syndrome.

BACKGROUND: Cockayne syndrome is an inherited heterogeneous defect in transcription-coupled DNA repair (TCR) cause severe clinical syndromes, which may affect the nervous system development of infants and even lead to premature death in some cases. ERCC8 diverse critical roles in the nucleotide excision repair (NER) complex, which is one of the disease-causing genes of Cockayne syndrome. METHODS AND RESULTS: The mutation of ERCC8 in the patient was identified and validated using WES and Sanger sequencing. Specifically, a compound heterozygous mutation (c.454_460dupGTCTCCA p. T154Sfs*13 and c.755_759delGTTTT p.C252Yfs*3) of ERCC8 (CSA) was found, which could potentially be the genetic cause of Cockayne syndrome in the proband. CONCLUSION: In this study, we identified a novel heterozygous mutation of ERCC8 in a Chinese family with Cockayne syndrome, which enlarging the genetic spectrum of the disease.

Identification of truncated variants in GLI family zinc finger 3 (GLI3) associated with polydactyly.

BACKGROUND: Polydactyly is a prevalent congenital anomaly with an incidence of 2.14 per 1000 live births in China. GLI family zinc finger 3 (GLI3) is a classical causative gene of polydactyly, and serves as a pivotal transcription factor in the hedgehog signaling pathway, regulating the development of the anterior-posterior axis in limbs. METHODS: Three pedigrees of polydactyly patients were enrolled from Hunan Province, China. Pathogenic variants were identified by whole-exome sequencing (WES) and Sanger sequencing. RESULTS: Three variants in GLI3 were identified in three unrelated families, including a novel deletion variant (c.1372del, p.Thr458GlnfsTer44), a novel insertion-deletion (indel) variant (c.1967_1968delinsAA, p.Ser656Ter), and a nonsense variant (c.2374 C > T, p.Arg792Ter). These variants were present exclusively in patients but not in healthy individuals. CONCLUSIONS: We identified three pathogenic GLI3 variants in polydactyly patients, broadening the genetic spectrum of GLI3 and contributing significantly to genetic counseling and diagnosis for polydactyly.

RTN3 deficiency exacerbates cisplatin-induced acute kidney injury through the disruption of mitochondrial stability.

Reticulum 3 (RTN3) is an endoplasmic reticulum (ER) protein that has been reported to act in neurodegenerative diseases and lipid metabolism. However, the role of RTN3 in acute kidney injury (AKI) has not been explored. Here, we employed public datasets, patient data, and animal models to explore the role of RTN3 in AKI. The underlying mechanisms were studied in primary renal tubular epithelial cells and in the HK2 cell line. We found reduced expression of RTN3 in AKI patients, cisplatin-induced mice, and cisplatin-treated HK2 cells. RTN3-null mice exhibit more severe AKI symptoms and kidney fibrosis after cisplatin treatment. Mitochondrial dysfunction was also found in cells with RTN3 knockdown or knockout. A mechanistic study revealed that RTN3 can interact with HSPA9 in kidney cells. RTN3 deficiency may disrupt the RTN3-HSPA9-VDAC2 complex and affect MAMs during ER-mitochondrion contact, which further leads to mitochondrial dysfunction and exacerbates cisplatin-induced AKI. Our study indicated that RTN3 was important in the kidney and that a decrease in RTN3 in the kidney might be a risk factor for the aggravation of AKI.

Correction to: Increased RTN3 phenocopies nonalcoholic fatty liver disease by inhibiting the AMPK-IDH2 pathway.

[This corrects the article DOI: 10.1002/mco2.226.].

Reticulon 3 regulates sphingosine-1-phosphate synthesis in endothelial cells to control blood pressure.

The discovery of the endothelium as a major regulator of vascular tone triggered intense research among basic and clinical investigators to unravel the physiologic and pathophysiologic significance of this phenomenon. Sphingosine-l-phosphate (S1P), derived from the vascular endothelium, is a significant regulator of blood pressure. However, the mechanisms underlying the regulation of S1P biosynthetic pathways in arteries remain to be further clarified. Here, we reported that Reticulon 3 (RTN3) regulated endothelial sphingolipid biosynthesis and blood pressure. We employed public datasets, patients, and mouse models to explore the pathophysiological roles of RTN3 in blood pressure control. The underlying mechanisms were studied in human umbilical vein endothelial cells (HUVECs). We reported that increased RTN3 was found in patients and that RTN3-null mice presented hypotension. In HUVECs, RTN3 can regulate migration and tube formation via the S1P signaling pathway. Mechanistically, RTN3 can interact with CERS2 to promote the selective autophagy of CERS2 and further influence S1P signals to control blood pressure. We also identified an RTN3 variant (c.116C>T, p.T39M) in a family with hypertension. Our data provided the first evidence of the association between RTN3 level changes and blood pressure anomalies and preliminarily elucidated the importance of RTN3 in S1P metabolism and blood pressure regulation.

The role of modeling and simulation in pediatric clinical trials / 国际药学研究杂志

Children’ s ability to dispose of drugs and the efficacy/safety of drugs for children differ from those adults as children are in the process of growth and development. In general,medication for children in a certain age group should be supported by clinical trial data from the corresponding pediatric population. However,compared with clinical trials in adults,children’s clinical trials have many challenges such as the ethical limitation and the difficulty in enrolling subjects. As a result,the use of drugs for children is often not formally approved by the drug regulatory authori- ties. At present,researchers tend to apply modeling and simulation to clinical trials,and conduct prospective studies be- fore the clinical use of drug to predict the optimal dosage regimen for children of different ages. In particular,there have been several successful cases in determining the optimal sample size for clinical trials based on the optimal design theory, optimizing sampling time point using the prior information from modeling,and processing sparse data by the Bayesian principle. This paper summarizes the role of modeling and simulation in pediatric clinical trials by reviewing previously reported clinical trial literature.