Effect of standard and neutral-pH peritoneal dialysis solutions upon fibroblasts proliferation.

INTRODUCTION: Continuous exposition of the peritoneal membrane to conventional dialysis solutions is an important risk factor for inducing structural and functional alterations. OBJECTIVE: To compare in vitro mouse fibroblast NIH-3T3 cell viability after exposition to a neutral pH dialysis solution in comparison to cells exposed to a standard solution. METHODS: Experimental study to compare the effects of a conventional standard or a neutral-pH, low-glucose degradation products peritoneal dialysis solution on the viability of exposed fibroblasts in cell culture. Both solutions were tested in all the commercially available glucose concentrations. Cell viability was evaluated with tetrazolium salt colorimetric assay. RESULTS: Fibroblast viability was significantly superior in the neutral pH solution in comparison to control, in all three glucose concentrations (Optical density in nm-means ± SD: 1.5% 0.295 ± 0.047 vs. 0.372 ± 0.042, p < 0.001; 2.3% 0.270 ± 0.036 vs. 0.337 ± 0.051, p < 0.001; 4.25% 0.284 ± 0.037 vs. 0.332 ± 0.032, p < 0.001; control vs. neutral pH respectively, Student t Test). There was no significant difference in cell viability between the three concentrations of glucose when standard solution was used (ANOVA p = 0.218), although cell viability was higher after exposition to neutral pH peritoneal dialysis fluid at 1.5% in comparison to 2.3 and 4.25% glucose concentrations (ANOVA p = 0.008: Bonferroni 1.5% vs. 2.3% p = 0.033, 1.5% vs. 4.25% p = 0.014, 2.3% vs. 4.25% p = 1.00). CONCLUSION: Cell viability was better in neutral pH dialysis solution, especially in the lower glucose concentration. A more physiological pH and lower glucose degradation products may be responsible for such results.

Effect of standard and neutral-pH peritoneal dialysis solutions upon fibroblasts proliferation / Efeito da solução de diálise peritoneal com pH neutro e padrão sobre a proliferação de fibroblastos

Introduction: Continuous exposition of the peritoneal membrane to conventional dialysis solutions is an important risk factor for inducing structural and functional alterations. Objective: To compare in vitro mouse fibroblast NIH-3T3 cell viability after exposition to a neutral pH dialysis solution in comparison to cells exposed to a standard solution. Methods: Experimental study to compare the effects of a conventional standard or a neutral-pH, low-glucose degradation products peritoneal dialysis solution on the viability of exposed fibroblasts in cell culture. Both solutions were tested in all the commercially available glucose concentrations. Cell viability was evaluated with tetrazolium salt colorimetric assay. Results: Fibroblast viability was significantly superior in the neutral pH solution in comparison to control, in all three glucose concentrations (Optical density in nm-means ± SD: 1.5% 0.295 ± 0.047 vs. 0.372 ± 0.042, p < 0.001; 2.3% 0.270 ± 0.036 vs. 0.337 ± 0.051, p < 0.001; 4.25% 0.284 ± 0.037 vs. 0.332 ± 0.032, p < 0.001; control vs. neutral pH respectively, Student t Test). There was no significant difference in cell viability between the three concentrations of glucose when standard solution was used (ANOVA p = 0.218), although cell viability was higher after exposition to neutral pH peritoneal dialysis fluid at 1.5% in comparison to 2.3 and 4.25% glucose concentrations (ANOVA p = 0.008: Bonferroni 1.5% vs. 2.3% p = 0.033, 1.5% vs. 4.25% p = 0.014, 2.3% vs. 4.25% p = 1.00). Conclusion: Cell viability was better in neutral pH dialysis solution, especially in the lower glucose concentration. A more physiological pH and lower glucose degradation products may be responsible for such results. .

Introdução: A exposição contínua da membrana peritoneal a soluções convencionais de diálise é um importante fator de risco para induzir alterações estruturais e funcionais. Objetivo: Comparar a viabilidade in vitro dos fibroblastos NIH-3T3 de camundongo após exposição à solução de diálise com pH neutro com células expostas à solução padrão. Métodos: Estudo experimental; ambas as soluções foram testadas em todas as concentrações de glicose comercialmente disponíveis. A viabilidade celular foi avaliada por ensaio colorimétrico de sal tetrazólio. Resultados: A viabilidade de fibroblastos foi melhor na solução de pH neutro em relação ao controle nas três concentrações de glicose (densidade óptica em nm-médias ± DP: 1,5% 0,295 ± 0,047 vs. 0,372 ± 0,042, p < 0,001; 2,3% 0,270 ± 0,036 vs. 0,337 ± 0,051, p < 0,001; 4,25% 0,284 ± 0,037 vs. 0,332 ± 0,032, p < 0,001; controle vs. pH neutro respectivamente, teste t de Student). Não houve diferença significativa na viabilidade celular entre as três concentrações de glicose quando solução padrão foi utilizada (ANOVA p = 0,218), embora a viabilidade celular tenha sido superior após exposição aos fluidos de diálise peritoneal neutros, pH 1,5% em comparação com 2,3 e 4,25% de concentrações de glicose (ANOVA p = 0,008: Bonferroni 1,5% vs. 2,3% p = 0,033, 1,5% vs. 4,25% p = 0,014, 2,3% vs. 4,25% p = 1,0). Conclusão: A viabilidade celular foi melhor em solução neutra de pH de diálise, especialmente nas menores concentrações de glicose. O pH fisiológico e com menos produtos de degradação de glicose podem ser responsáveis por estes resultados. .