Acinetobacter baumanniiLipopolysaccharide Influences Adipokine Expression in 3T3-L1 Adipocytes

Abstract

Acinetobacter baumanniiis one of the most important nosocomial opportunistic pathogen worldwide. In addition, obesity has been associated with an increased risk of nosocomial infection, suggesting that there may be an association betweenA. baumanniiand white adipose tissue. However, the effects ofA. baumanniion adipocytes have not been well studied at the molecular level. Here, we investigated the potential role ofA. baumannii-derived lipopolysaccharides (LPS) as signaling molecules that affect adipocyte functionality. We tested the effect of increasing concentrations ofA. baumannii-derived LPS (10, 100, or 1000 ng/mL) on the 3T3-L1 adipocyte cell line. Exposure to LPS was found to increase the expression of several adipokines (e.g., MIP-2, MCP-1, TNF-α, IL-6, lipocalin-2, and FABP4) in 3T3-L1 adipocytes and significantly reduced the expression of leptin and adiponectin. The effects ofA. baumannii-derived LPS on MIP-2 expression were similar in comparison with that of LPS prepared fromPseudomonas aeruginosaandEscherichia coliin our cell culture-based system. This study suggests thatA. baumannii-derived LPS functions as a signaling molecule that impacts the inflammatory function of white adipose tissue on the level of gene expression.