The effect of sodium bicarbonate on cytokine secretion in CKD patients with metabolic acidosis

The incidence of acidosis increases with the progression of chronic kidney disease (CKD). Correction of acidosis by sodium bicarbonate may slow CKD deterioration. Inflammation, which is common in CKD, may be related to acidosis. Whether the slower rate of GFR decline following the correction of acidosis is related to changes in inflammatory markers is unknown. The current study examined whether correcting CKD-acidosis affected inflammatory cytokines secretion. Thirteen patients with CKD 4-5 and acidosis were tested for cytokines secretion from peripheral-blood mononuclear cells at baseline and after one month of oral sodium bicarbonate. Following treatment with sodium bicarbonate there was no change in weight, blood pressure, serum creatinine, albumin, sodium, calcium, phosphate, PTH, hemoglobin and CRP. Serum urea decreased (134 ± 10-116 ± 8. mg/dl, P = 0.002), potassium decreased (5.1 ± 0.4-4.8 ± 0.1. mequiv./l, P = 0.064), pH increased (7.29 ± 0.01-7.33 ± 0.01, P = 0.008), and serum bicarbonate increased (18.6 ± 0.4. mequiv./l to 21.3 ± 0.3. mequiv./l, P = 0.001). The secretion of the anti-inflammatory cytokine IL-10 decreased (2.75 ± 0.25. ng/ml to 2.29 ± 0.21. ng/ml, P = 0.041). There was no significant change in the secretion of the other pro-inflammatory and anti-inflammatory cytokines, including IL-1β, IL-2, IL-6, TNFα, IFNγ, IL-1ra. Thus, correcting acidosis in CKD with bicarbonate decreases IL-10 secretion. Its significance needs to be further investigated.