The effect of dialysis membrane type on plasma concentrations of pentosidine, a marker of carbonyl stress, in hemodialyzed patients.

INTRODUCTION

Advanced glycation end products (AGEs), which accumulate in plasma of hemodialyzed patients, participate in the development of complications associated with hemodialysis (HD). Carbonyl stress plays an essential role in the formation of AGEs, including pentosidine.

OBJECTIVES

The aim of the study was to assess the effect of various low-flux dialysis membranes on plasma concentrations of total (P(tot)) and free (P(free)) pentosidine.

PATIENTS AND METHODS

We examined 56 adult patients (aged 50 +/-13 years) on chronic HD. Plasma pentosidine concentrations were measured with high-performance liquid chromatography with fluorescence detection. Plasma proteins were subjected to acid hydrolysis or precipitation with trichloroacetic acid before measurement of P(tot) and P(free), respectively.

RESULTS

Significantly lower concentrations of P(tot) were observed in patients dialyzed with polysulfone than non-polysulfone membranes before the HD session (22.0 +/-11.9 vs 34.4 +/-12.5 pmol/mg protein, respectively, p = 0.0008) and after the HD session (22.5 +/-12.9 vs 32.9 +/-12.0 pmol/mg protein, p = 0.004). Moreover, there was a strong inverse correlation between the percentage of HD sessions performed with polysulfone membranes during the last 3 months and P(tot) concentration before HD (Rs = -0.44, p = 0.0011) and after HD (Rs = -0.45, p = 0.00073).

CONCLUSIONS

The results suggest that polysulfone membranes reduce carbonyl stress more effectively than modified or unmodified cellulose membranes in patients on chronic HD. Determination of plasma pentosidine in hemodialyzed patients may help in comparing the physicochemical and biological properties of dialysis membranes. It may also contribute to the development of optimal strategies for renal replacement therapy.