Publications

What is a Publication?
4 Publications visible to you, out of a total of 4

Abstract (Expand)

Pollution with metals and metalloids is a global problem that adversely affects human health and environment. Although several studies have reported gene expression changes in response to human exposures to metals, there are a limited number of studies exploring the effect of long-term residence in mining areas. The evidence of increased levels of several essential and non-essential metals in soil, water, and plants in Kapan mining area (Armenia) has been previously demonstrated in several environmental studies. Our study investigated the impact of long-term residence in this mining area on the transcriptome state of human peripheral blood mononuclear cells and the possible association of transcriptome changes with the blood metallome. In total, 58 participants including 27 mining region residents (MRR) and 31 non-mining region residents (NMR) were selected for our study. Transcriptomic analysis of peripheral blood mononuclear cells was performed by mRNA sequencing. Differential expression analyses were conducted using generalized linear modeling, optimized for participant demographics, cell types, and sequencing technical factors, followed by pathway analysis. The study revealed that long-term residence in a mining area is correlated with alterations in the blood transcriptome, with responses varying by sex. The identified transcriptome changes were enriched for pathways related to immune response and RNA translation. These changes correlated with higher blood levels of a mixture of non-essential metals, including arsenic, antimony, nickel, thallium, and beryllium. Additionally, the study identified differences in the transcriptome response between male and female MRR. While females exhibited a stronger immune response, males show dysregulation in ion transport and epigenetic modifications. Our findings contribute to understanding the effects of long-term residence in mining regions and can aid in developing more effective risk assessment and mitigation approaches in target populations.

Authors: A. Stepanyan, A. Arakelyan, J. Schug

Date Published: 24th Mar 2025

Publication Type: Journal

Abstract (Expand)

BACKGROUND: Long-term consumption of Western Diet (WD) is a well-established risk factor for the development of cardiovascular disease (CVD); however, there is a paucity of studies on the long-term effects of WD on the pathophysiology of CVD and sex-specific responses. METHODS: Our study aimed to investigate the sex-specific pathophysiological changes in left ventricular (LV) function using transthoracic echocardiography (ECHO) and LV tissue transcriptomics in WD-fed C57BL/6 J mice for 125 days, starting at the age of 300 through 425 days. RESULTS: In female mice, consumption of the WD diet showed long-term effects on LV structure and possible development of HFpEF-like phenotype with compensatory cardiac structural changes later in life. In male mice, ECHO revealed the development of an HFrEF-like phenotype later in life without detectable structural alterations. The transcriptomic profile revealed a sex-associated dichotomy in LV structure and function. Specifically, at 530-day, WD-fed male mice exhibited differentially expressed genes (DEGs), which were overrepresented in pathways associated with endocrine function, signal transduction, and cardiomyopathies. At 750 days, WD-fed male mice exhibited dysregulation of several genes involved in various lipid, glucagon, and glutathione metabolic pathways. At 530 days, WD-fed female mice exhibited the most distinctive set of DEGs with an abundance of genes related to circadian rhythms. At 640 days, altered DEGs in WD-fed female mice were associated with cardiac energy metabolism and remodeling. CONCLUSIONS: Our study demonstrated distinct sex-specific and age-associated differences in cardiac structure, function, and transcriptome signature between WD-fed male and female mice.

Authors: A. Stepanyan, A. Brojakowska, R. Zakharyan, S. Hakobyan, S. Davitavyan, T. Sirunyan, G. Khachatryan, M. K. Khlgatian, M. Bisserier, S. Zhang, S. Sahoo, L. Hadri, A. Rai, V. N. S. Garikipati, A. Arakelyan, D. A. Goukassian

Date Published: 28th Dec 2024

Publication Type: Journal

Abstract (Expand)

Most high throughput genomic data analysis pipelines currently rely on over-representation or gene set enrichment analysis (ORA/GSEA) approaches for functional analysis. In contrast, topology-based pathway analysis methods, which offer a more biologically informed perspective by incorporating interaction and topology information, have remained underutilized and inaccessible due to various limiting factors. These methods heavily rely on the quality of pathway topologies and often utilize predefined topologies from databases without assessing their correctness. To address these issues and make topology-aware pathway analysis more accessible and flexible, we introduce the PSF (Pathway Signal Flow) toolkit R package. Our toolkit integrates pathway curation and topology-based analysis, providing interactive and command-line tools that facilitate pathway importation, correction, and modification from diverse sources. This enables users to perform topology-based pathway signal flow analysis in both interactive and command-line modes. To showcase the toolkit's usability, we curated 36 KEGG signaling pathways and conducted several use-case studies, comparing our method with ORA and the topology-based signaling pathway impact analysis (SPIA) method. The results demonstrate that the algorithm can effectively identify ORA enriched pathways while providing more detailed branch-level information. Moreover, in contrast to the SPIA method, it offers the advantage of being cut-off free and less susceptible to the variability caused by selection thresholds. By combining pathway curation and topology-based analysis, the PSF toolkit enhances the quality, flexibility, and accessibility of topology-aware pathway analysis. Researchers can now easily import pathways from various sources, correct and modify them as needed, and perform detailed topology-based pathway signal flow analysis. In summary, our PSF toolkit offers an integrated solution that addresses the limitations of current topology-based pathway analysis methods. By providing interactive and command-line tools for pathway curation and topology-based analysis, we empower researchers to conduct comprehensive pathway analyses across a wide range of applications.

Authors: S. Hakobyan, A. Stepanyan, L. Nersisyan, H. Binder, A. Arakelyan

Date Published: 8th Sep 2023

Publication Type: Journal

Abstract (Expand)

BACKGROUND: Long-term environmental exposure to metals leads to epigenetic changes and may increase risks to human health. The relationship between the type and level of metal exposure and epigenetic changes in subjects exposed to high concentrations of metals in the environment is not yet clear. The aim of our study is to find the possible association of environmental long-term exposure to metals with DNA methylation changes of genes related to immune response and carcinogenesis. We investigated the association of plasma levels of 21 essential and non-essential metals detected by ICP-MS and the methylation level of 654 CpG sites located on NFKB1, CDKN2A, ESR1, APOA5, IGF2 and H19 genes assessed by targeted bisulfite sequencing in a cohort of 40 subjects living near metal mining area and 40 unexposed subjects. Linear regression was conducted to find differentially methylated positions with adjustment for gender, age, BMI class, smoking and metal concentration. RESULTS: In the metal-exposed group, five CpGs in the NFKB1 promoter region were hypomethylated compared to unexposed group. Four differentially methylated positions (DMPs) were associated with multiple metals, two of them are located on NFKB1 gene, and one each on CDKN2A gene and ESR1 gene. Two DMPs located on NFKB1 (chr4:102500951, associated with Be) and IGF2 (chr11:2134198, associated with U) are associated with specific metal levels. The methylation status of the seven CpGs located on NFKB1 (3), ESR1 (2) and CDKN2A (2) positively correlated with plasma levels of seven metals (As, Sb, Zn, Ni, U, I and Mn). CONCLUSIONS: Our study revealed methylation changes in NFKB1, CDKN2A, IGF2 and ESR1 genes in individuals with long-term human exposure to metals. Further studies are needed to clarify the effect of environmental metal exposure on epigenetic mechanisms and pathways involved.

Authors: A. Stepanyan, A. Petrackova, S. Hakobyan, J. Savara, S. Davitavyan, E. Kriegova, A. Arakelyan

Date Published: 7th Aug 2023

Publication Type: Journal

Powered by
(v.1.15.0-main)
Copyright © 2008 - 2024 The University of Manchester and HITS gGmbH