Diabetic kidney disease (DKD) is the most common microvascular complication of type 2 diabetes mellitus (2-DM). Currently, urine and kidney biopsy specimens are the major clinical resources for DKD diagnosis. Our study proposes to evaluate the diagnostic value of blood in monitoring the onset of DKD and distinguishing its status in the clinic. This study recruited 1,513 participants including healthy adults and patients diagnosed with 2-DM, early-stage DKD (DKD-E), and advanced-stage DKD (DKD-A) from 4 independent medical centers. One discovery and four testing cohorts were established. Sera were collected and subjected to training proteomics and large-scale metabolomics. Deep profiling of serum proteomes and metabolomes revealed several insights. First, the training proteomics revealed that the combination of α₂-macroglobulin, cathepsin D, and CD324 could serve as a surrogate protein biomarker for monitoring DKD progression. Second, metabolomics demonstrated that galactose metabolism and glycerolipid metabolism are the major disturbed metabolic pathways in DKD, and serum metabolite glycerol-3-galactoside could be used as an independent marker to predict DKD. Third, integrating proteomics and metabolomics increased the diagnostic and predictive stability and accuracy for distinguishing DKD status. Serum integrative omics provide stable and accurate biomarkers for early warning and diagnosis of DKD. Our study provides a rich and open-access data resource for optimizing DKD management.

Our group recently characterized a cell-autonomous mammalian 12-h clock independent from the circadian clock, but its function and mechanism of regulation remain poorly understood. Here, we show that in mouse liver, transcriptional regulation significantly contributes to the establishment of 12-h rhythms of mRNA expression in a manner dependent on Spliced Form of X-box Binding Protein 1 (XBP1s). Mechanistically, the motif stringency of XBP1s promoter binding sites dictates XBP1s’s ability to drive 12-h rhythms of nascent mRNA transcription at dawn and dusk, which are enriched for basal transcription regulation, mRNA processing and export, ribosome biogenesis, translation initiation, and protein processing/sorting in the Endoplasmic Reticulum (ER)-Golgi in a temporal order consistent with the progressive molecular processing sequence described by the central dogma information flow (CEDIF). We further identified GA-binding proteins (GABPs) as putative novel transcriptional regulators driving 12-h rhythms of gene expression with more diverse phases. These 12-h rhythms of gene expression are cell autonomous and evolutionarily conserved in marine animals possessing a circatidal clock. Our results demonstrate an evolutionarily conserved, intricate network of transcriptional control of the mammalian 12-h clock that mediates diverse biological pathways. We speculate that the 12-h clock is coopted to accommodate elevated gene expression and processing in mammals at the two rush hours, with the particular genes processed at each rush hour regulated by the circadian and/or tissue-specific pathways.

A cell-autonomous 12-hour clock coordinates nuclear speckle LLPS with proteostasis control.

Obesity is increasing worldwide and leads to a multitude of metabolic diseases, including cardiovascular disease, type 2 diabetes, nonalcoholic fatty liver disease, and nonalcoholic steatohepatitis (NASH). Cysteine-rich angiogenic inducer 61 (CYR61) is associated with the progression of NASH, but it has been described to have anti- and proinflammatory properties. We sought to examine the role of liver CYR61 in NASH progression. CYR61 liver-specific knockout mice on a NASH diet showed improved glucose tolerance, decreased liver inflammation, and reduced fibrosis. CYR61 polarized infiltrating monocytes promoting a proinflammatory/profibrotic phenotype through an IRAK4/SYK/NF-κB signaling cascade. In vitro, CYR61 activated a profibrotic program, including PDGFa/PDGFb expression in macrophages, in an IRAK4/SYK/NF-κB–dependent manner. Furthermore, targeted-antibody blockade reduced CYR61-driven signaling in macrophages in vitro and in vivo, reducing fibrotic development. This study demonstrates that CYR61 is a key driver of liver inflammation and fibrosis in NASH.

Nonalcoholic fatty liver disease (NAFLD) is the most common type of chronic liver disease in children. The mechanisms that drive NAFLD disease progression in this specific patient population remain poorly defined. In this study, we obtained liver biopsy samples from a multiethnic cohort of pediatric patients with NAFLD (n = 52, mean age = 13.6 years) and healthy liver controls (n = 5). We analyzed transcriptomic changes associated with NAFLD stages using high‐throughput RNA sequencing. Unsupervised clustering as well as pairwise transcriptome comparison distinguished NAFLD from healthy livers. We identified perturbations in pathways including calcium and insulin/glucose signaling occurring early in NAFLD disease, before the presence of histopathologic evidence of advanced disease. Transcriptomic comparisons identified a 25‐gene signature associated with the degree of liver fibrosis. We also identified expression of the insulin‐like growth factor binding protein (IGFBP) gene family (1/2/3/7) as correlating with disease stages, and it has the potential to be used as a peripheral biomarker in NAFLD. Comparing our data set with publicly available adult and adolescent transcriptomic data, we identified similarities and differences in pathway enrichment and gene‐expression profiles between adult and pediatric patients with NAFLD. Regulation of genes including interleukin‐32, IGFBP1, IGFBP2, and IGFBP7 was consistently found in both NAFLD populations, whereas IGFBP3 was specific to pediatric NAFLD. Conclusion: This paper expands our knowledge on the molecular mechanisms underlying pediatric NAFLD. It identifies potential biomarkers and directs us toward new therapies in this population.