Expressional profile of the diacylglycerol kinase eta gene DGKH

High glucose induces tau hyperphosphorylation in hippocampal neurons via inhibition of ALKBH5-mediated Dgkh m6A demethylation: a potential mechanism for diabetic cognitive dysfunction

Tau hyperphosphorylation in hippocampal neurons has an important pathogenetic role in the development of diabetic cognitive dysfunction. N6-methyladenosine (m6A) methylation is the most common modification of eukaryotic mRNA and is involved in regulating diverse biological processes. However, the role of m6A alteration in tau hyperphosphorylation of hippocampus neurons has not been reported. We found lower ALKBH5 expression in the hippocampus of diabetic rats and in HN-h cells with high-glucose intervention, accompanied by tau hyperphosphorylation. ALKBH5 overexpression significantly reversed tau hyperphosphorylation in high-glucose-stimulated HN-h cells. Furthermore, we found and confirmed by m6A-mRNA epitope transcriptome microarray and transcriptome RNA sequencing coupled with methylated RNA immunoprecipitation that ALKBH5 regulates the m6A modification of Dgkh mRNA. High glucose inhibited the demethylation modification of Dgkh by ALKBH5, resulting in decreases in Dgkh mRNA and protein levels. Overexpression of Dgkh reversed tau hyperphosphorylation in HN-h cells after high-glucose stimulation. Overexpression of Dgkh by adenovirus suspension injection into the bilateral hippocampus of diabetic rats significantly ameliorated tau hyperphosphorylation and diabetic cognitive dysfunction. In addition, ALKBH5 targeted Dgkh to activate PKC-α, leading to tau hyperphosphorylation under high-glucose conditions. The results of this study reveal that high glucose suppresses the demethylation modification of Dgkh by ALKBH5, which downregulates Dgkh and leads to tau hyperphosphorylation through activation of PKC-α in hippocampal neurons. These findings may indicate a new mechanism and a novel therapeutic target for diabetic cognitive dysfunction.

Machine learning-based metabolism-related genes signature and immune infiltration landscape in diabetic nephropathy

BACKGROUND

To identify the diagnostic biomarkers of metabolism-related genes (MRGs), and investigate the association of the MRGs and immune infiltration landscape in diabetic nephropathy (DN).

METHODS

The transcriptome matrix was downloaded from the GEO database. R package "limma" was utilized to identify the differential expressed MRGs (DE-MRGs) of HC and DN samples. Genetic Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses of DE-MRGs were performed using "clusterProfiler" R package. WGCNA, LASSO, SVM-RFE, and RFE algorithms were employed to select the diagnostic feature biomarkers for DN. The ROC curve was used to evaluate discriminatory ability for diagnostic feature biomarkers. CIBERSORT algorithm was performed to investigate the fraction of the 22-types immune cells in HC and DN group. The correlation of diagnostic feature biomarkers and immune cells were performed via Spearman-rank correlation algorithm.

RESULTS

A total of 449 DE-MRGs were identified in this study. GO and KEGG pathway enrichment analysis indicated that the DE-MRGs were mainly enriched in small molecules catabolic process, purine metabolism, and carbon metabolism. ADI1, PTGS2, DGKH, and POLR2B were identified as diagnostic feature biomarkers for DN via WGCNA, LASSO, SVM-RFE, and RFE algorithms. The result of CIBERSORT algorithm illustrated a remarkable difference of immune cells in HC and DN group, and the diagnostic feature biomarkers were closely associated with immune cells.

CONCLUSION

ADI1, PTGS2, DGKH, and POLR2B were identified as diagnostic feature biomarkers for DN, and associated with the immune infiltration landscape, providing a novel perspective for the future research and clinical management for DN.

Immunocytochemical Analysis of DGKη in Cultured Cells Using a Monoclonal Antibody DhMab-4

Diacylglycerol kinase (DGK) is a lipid kinase that converts diacylglycerol (DG) to phosphatidic acid (PA). Since both DG and PA serve as intracellular second messenger molecules, DGK plays a pivotal role in balancing these two signaling pathways. Of the DGK family, DGKη is classified as a type II DGK. Reportedly, DGKη is expressed ubiquitously through mammalian tissues and cells. Previous studies using cDNA transfection methods reported cytoplasmic localization of DGKη in cultured human cells. However, subcellular localization of native protein is still unknown. Recently, we established a human DGKη-specific monoclonal antibody, DhMab-4. In this study, we examined subcellular localization of native protein of DGKη using DhMab-4 by immunocytochemistry in human cultured cells.

Genome-wide association analyses of lesion counts in group-housed pigs

Aggression in group-housed pigs is a welfare concern and can negatively affect production. Skin lesions are reliable indicators of aggression and are moderately heritable, suggesting that selective breeding may reduce aggression. To further understand the genetic control of behavioral traits, such as the aggressive response to regrouping, associated single nucleotide polymorphisms (SNPs) can be identified within the genome, and the region in which these SNPs are located can be related to known genes. To investigate SNPs associated with aggression, 1093 purebred Yorkshire pigs were strategically remixed into new groups of familiar and unfamiliar animals at three life stages and lesion counts were recorded. Genomic best linear unbiased prediction (GBLUP) models were fitted for each trait. The genetic additive effect was obtained from a genetic relationship matrix constructed from the 50 924 SNPs. SNP effects and their variances were estimated from the GBLUP objects. SNPs that were associated with a significant portion of the trait variance were identified for lesions to the anterior (three SNPs, FDR <5%) and central (one SNP, FDR <5%) portions of the body in grow-finish pigs. These SNPs were located on chromosome 11, suggesting that chromosome 11 contains a region explaining variation in lesion counts that should be further explored to identify genes underlying biological control of aggression.