HMGB1 and acute kidney injury: Interestingly, studies have shown that HMGB1 deletion in renal tubules has no noticeable effect on renal injury in the early stage after unilateral ureteral obstruction (UUO) but greatly alleviates renal interstitial fibrosis in the late/subacute stage10, suggesting that HMGB1 may play additional roles in CKD than differ from those in acute kidney injury.