Faculty, Staff and Student Publications

Language

English

Publication Date

2-28-2025

Journal

The FASEB Journal

DOI

10.1096/fj.202402531R

PMID

39985299

PMCID

PMC11846021

PubMedCentral® Posted Date

2-22-2025

PubMedCentral® Full Text Version

Post-print

Abstract

High fructose corn syrup (HFCS) is a commonly used sweetener in soft drinks and processed foods, and HFCS exacerbates inflammation when consumed in excess. Fructose, a primary component of HFCS; however, it is unclear whether fructose directly activates inflammatory signaling. Growth hormone secretagogue receptor (GHSR) is a receptor of the nutrient‐sensing hormone ghrelin. We previously reported that GHSR ablation mitigates HFCS‐induced inflammation in adipose tissue and liver, shifting macrophages toward an anti‐inflammatory spectrum. Since inflammation is primarily governed by innate immune cells, such as macrophages in the peripheral tissues and microglia in the brain, this study aims to investigate whether GHSR autonomously regulates pro‐inflammatory activation in macrophages and microglia upon fructose exposure. GHSR deletion mutants of RAW 264.7 macrophages and the immortalized microglial cell line (IMG) were generated using CRISPR‐Cas9 gene editing. After treating the cells with equimolar concentrations of fructose or glucose for 24 h, fructose increased mRNA and protein expression of GHSR and pro‐inflammatory cytokines (Il1βIl6, and Tnfα) in both macrophages and microglia, suggesting that fructose activates Ghsr and induces inflammation directly in macrophages and microglia. Remarkably, GHSR deletion mutants (Ghsr mutant) of macrophages and microglia exhibited reduced inflammatory responses to fructose, indicating that GHSR mediates fructose‐induced inflammation. Furthermore, we found that GHSR regulates fructose transport and fructose metabolism and mediates fructose‐induced inflammatory activation through CREB–AKT‐NF‐κB and p38 MAPK signaling pathways. Our results underscore that fructose triggers inflammation, and reducing HFCS consumption would reduce disease risk. Moreover, these findings reveal for the first time that the nutrient‐sensing receptor GHSR plays a crucial role in fructose‐mediated inflammatory activation, suggesting that targeting GHSR may be a promising therapeutic approach to combat the immunotoxicity of foods that contain fructose.

Keywords

Animals, Microglia, Mice, Receptors, Ghrelin, Fructose, Macrophages, Inflammation, RAW 264.7 Cells, Signal Transduction, fructose, growth hormone secretagogue receptor (GHSR), inflammation, macrophage, microglia

Published Open-Access

yes

Share

COinS
 
 

To view the content in your browser, please download Adobe Reader or, alternately,
you may Download the file to your hard drive.

NOTE: The latest versions of Adobe Reader do not support viewing PDF files within Firefox on Mac OS and if you are using a modern (Intel) Mac, there is no official plugin for viewing PDF files within the browser window.