Brown adipocytes and β-stimulant-induced brown-like adipocytes contribute to the prevention of renal crystal formation.

According to recent studies, kidney stones are associated with metabolic syndrome. We focused on brown adipocytes and β-stimulant-induced brown-like adipocytes to investigate how these adipocytes influence kidney stone disease. For the interscapular brown adipose tissue (iBAT) removal experiment, mice were subjected to either iBAT removal or sham operation (X-BAT group or sham group), and, after 3 wk, renal crystal deposition was induced by intra-abdominal injection of glyoxylate (GOX) for 6 days. For the β-stimulant experiment, mice were administered intra-abdominal injections of the β-stimulant (β-group) or saline (control group) for 6 days. Thereafter, renal crystal deposition was induced by intra-abdominal injection of GOX for 6 days. iBAT removal decreased the expression of and increased that of chemokine (C-C motif) ligand 2 (), EGF module-containing mucin-like receptor 1 (), and tumor necrosis factor () in the kidneys. Renal crystal deposition was 2.06-fold higher in the X-BAT group than in the sham group. The β-stimulant caused differentiation of white adipocytes into brown-like adipocytes. In the kidneys of the β-group, the expression of and decreased and that of increased. Renal crystal deposition was 0.17-fold lower in the β-group than in the control group. In summary, iBAT removal promoted kidney inflammation and renal crystal formation. β-Stimulant-induced brown-like adipocytes reduced inflammation and improved antioxidant action in the kidneys, which suppressed renal crystal formation. This is the first report on the therapeutic role of brown and brown-like adipocytes for kidney stone formation.