Systemic serum protein alterations and molecular mechanisms in alcohol dependence.

[INTRODUCTION] Most of the studies on alcohol dependence (AD) emphasize its impact on the nervous system and organ functions of the human body, but its molecular mechanism is largely unknown so far. This study determines serum protein changes in alcohol-dependent patients for the identification of biomarkers and the revelation of molecular mechanisms behind alcohol dependence.

[METHODS] Serum samples from seven newly diagnosed alcohol-dependent patients and four healthy controls are subjected to researcher-conducted proteomic analyses using data-independent acquisition (DIA) mass spectrometry. Functional enrichment analysis of gene activity and biological pathways is performed by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) to reveal key processes related to alcohol dependence. The expression of Small Nuclear Ribonucleoprotein Polypeptide B (SNRPB) is evaluated to assess its potential as a biomarker, and survival analysis is performed to investigate its clinical relevance.

[RESULTS] The mass spectrometry detected a total of 1,249 and 1,020 proteins in the serum from alcohol-dependent patients and healthy controls, respectively. Biomarker analysis identified 195 proteins as potential markers with a differentially expressed pattern. Among them, 99 proteins are upregulated and 96 proteins downregulated in alcohol-dependent patients compared with controls. The GO and KEGG pathway analysis revealed that alcohol-dependent patients exhibit enhanced activity in pathways related to adenosine triphosphate (ATP)-dependent chromatin remodeling and immune responses but reduced activity in metabolic pathways. Alcohol-dependent patients exhibited significantly higher levels of the SNRPB protein, suggesting its potential role in immune system regulation and cell growth control. Survival analysis results indicated that higher levels of SNRPB are linked to worse outcomes in liver cancer patients, specifically those with liver hepatocellular carcinoma (LIHC), suggesting it could be a useful biomarker for alcohol-related diseases.

[CONCLUSION] This study provides valuable insights into the systemic protein changes in alcohol dependence, identifying several potential biomarkers for early diagnosis and therapeutic targeting. The upregulation of SNRPB suggests its role as a potential biomarker in clinical applications.