Helicobacter pylori (H. pylori)
infection leads to gastric
inflammation,
peptic ulcer and gastric
carcinoma. H. pylori activates
NADPH oxidase and increases
reactive oxygen species (ROS), which induce NF-κB activation and
IL-8 expression in gastric epithelial cells. Dysfunctional mitochondria trigger inflammatory
cytokine production.
Peroxisome proliferator-activated receptors-γ (
PPAR-γ) regulate inflammatory response.
Astaxanthin is a powerful
antioxidant that protects cells against oxidative stress. The present study was aimed at determining whether
astaxanthin inhibits H. pylori-induced
mitochondrial dysfunction, NF-κB activation, and
IL-8 expression via
PPAR-γ activation in gastric epithelial cells. Gastric epithelial AGS cells were treated with
astaxanthin,
NADPH oxidase inhibitor
apocynin and
PPAR-γ antagonist
GW9662, and infected with H. pylori. As a result, H. pylori caused an increase in intracellular and mitochondrial ROS, NF-κB activation and
IL-8 expression, but decreased mitochondrial membrane potential and
ATP level.
Astaxanthin inhibited H. pylori-induced alterations (increased ROS,
mitochondrial dysfunction, NF-κB activation, and IL-8 expression).
Astaxanthin activated
PPAR-γ and its target gene
catalase in H. pylori-infected cells.
Apocynin reduced ROS and inhibited
IL-8 expression while
astaxanthin did not affect
NADPH oxidase activity. Inhibitory effects of
astaxanthin on ROS levels and
IL-8 expression were suppressed by addition of
GW9662. In conclusion,
astaxanthin inhibits H. pylori-induced
mitochondrial dysfunction and ROS-mediated
IL-8 expression by activating
PPAR-γ and
catalase in gastric epithelial cells.
Astaxanthin may be beneficial for preventing oxidative stress-mediated gastric
inflammation-associated H. pylori
infection.