The use of GH to treat heart failure has received considerable attention in recent years. Although the mechanisms of its beneficial effects are unknown, it has been implicated in the regulation of apoptosis in several cell types, and cardiomyocyte apoptosis is known to occur in heart failure. We therefore decided to investigate whether GH protects cardiomyocytes from apoptosis. Preliminary experiments confirmed the expression of the GH receptor (GHR) gene in primary cultures of neonatal rat cardiomyocytes (PC), the specific binding of GH by HL-1 cardiomyocytes, and the GH-induced activation of GHR and its classical downstream effectors in the latter. That GH prevented the apoptosis of PC cells deprived of serum for 48 h was shown by DNA electrophoresis and by Hoechst staining assays in which GH reduced the percentage of cells undergoing apoptosis. Similarly, the TUNEL-evaluated pro-apoptotic effect of cytosine arabinoside (AraC) on HL-1 cells was almost totally prevented by pre-treatment with GH. Fluorescence-activated cell sorter (FACS) analysis showed apoptosis in 9.7% of HL-1 cells growing in normal medium, 21.1% of those treated with AraC and 13.9% of those treated with AraC+GH, and that GH increased the percentage of AraC-treated cells in the S/G(2)/M phase from 36.9% to 52.8%. GH did not modify IGF-I mRNA levels or IGF-I secretion in HL-1 cells treated with AraC, and the protection afforded by GH against AraC-induced apoptosis in HL-1 cells was not affected by the presence of anti-IGF-I antibodies, but was largely abolished by the calcineurin-inhibiting combination cyclosporin+FK506. GH also reduced AraC-induced phosphorylation of mitogen-activated protein kinase p38 (MAPK p38) in HL-1 cells. In summary, GH protects PC and HL-1 cells from apoptosis. This effect is not mediated by IGF-I and may involve MAPK p38 as well as calcineurin.
Endothelial cell (EC) dysfunction is a well-established response to cardiovascular disease (CVD) risk factors, such as smoking and obesity. Risk factor exposure can modify EC signalling and behaviour, leading to arterial and venous disease development. Biomarker panels to assess EC dysfunction are lacking, but could be useful for risk stratification and to monitor treatment response. Here, we used affinity proteomics to identify EC-derived proteins circulating in plasma that were associated with CVD risk factor exposure. 216 proteins, known to be expressed in ECs across vascular beds, were measured in plasma samples (n=1005) from the population-based Swedish CArdioPulmonary bioImage Study (SCAPIS) pilot. We identified 38 EC-derived proteins that were associated with body mass index, total cholesterol, low density lipoprotein, smoking, hypertension or diabetes. Sex-specific analysis revealed female- and male-only associations were most frequently observed with BMI, or total cholesterol, respectively. We showed a relationship between individual CVD risk, calculated with the Framingham risk score, and the corresponding biomarker profiles; presenting the concept of measuring EC-derived proteins in plasma to infer vascular status.
Genes with cell type specific expression typically encode for proteins that have cell type specific functions. Single cell RNAseq (scRNAseq) has facilitated the identification of such genes, but various challenges limit the analysis of certain cell types and lowly expressed genes. Here, we performed an integrative network analysis of over 6000 bulk RNAseq datasets from 15 human organs, to generate a tissue-by-tissue cell type enrichment prediction atlas for all protein coding genes. We profile all the major constituent cell types, including several that are fragile or difficult to process and thus absent from existing scRNAseq-based atlases. The stability and read depth of bulk RNAseq data, and the high number of biological replicates analysed, allowed us to identify lowly expressed cell type enriched genes that are difficult to classify using existing methods. We identify co-enriched gene panels shared by pancreatic alpha and beta cells, chart temporal changes in cell enrichment signatures during spermatogenesis, and reveal that cells in the hair root are a major source of skin enriched genes. In a cross-tissue analysis, we identify shared gene enrichment signatures between highly metabolic and motile cell types, and core identity profiles of cell types found in across tissue types. Our study provides the only cell type gene enrichment atlas generated independently of scRNAseq, representing a new addition to our existing toolbox of resources for the understanding of gene expression across human tissues.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.