So-Min Oh, Un-Seong Na, Do-Youn Jeong, Hayoung Woo, Anna Han
Obesity causes chronic kidney damage. This study investigated the renoprotective effects of Gochujang, a Korean traditional fermented food, despite its high salt content. Gochujang extract (GE) significantly inhibited lipid accumulation and reduced inflammation-related proteins, including TNF-α, in renal tubular epithelial (HK-2) cells. Additionally, Gochujang markedly attenuated kidney injury-associated changes by lowering blood urea nitrogen (BUN) and kidney injury molecule-1 (KIM-1) levels, and by improving histopathology in high-fat diet (HD)-induced obese mice. Moreover, Gochujang altered HD-induced gut microbiota changes by increasing diversity and reducing the Firmicutes-to-Bacteroidetes ratio, whereas table salt had no effect. Importantly, alterations in the gut microbiota were strongly correlated with improvements in renal injury and inflammatory indicators, implying an association between the renoprotective effects of Gochujang and gut microbiota modulation. These findings highlight the potential of Gochujang to attenuate obesity-related kidney injury-related changes despite its high salt content.