Zugl.: Erlangen, Nürnberg, Universiẗat, Diss., 2008.

A icterícia costuma ser um fenômeno fisiológico em recém-nascidos saudáveis, contudo, hiperbilirrubinemia não conjugada grave ocorre em 5 a 6% dessa população. Tem sido sugerido que a variabilidade genética de genes de proteínas transportadoras de bilirrubina poderia aumentar o risco de hiperbilirrubinemia quando associada a outros fatores icterogênicos. O presente estudo incluiu neonatos com idade gestacional de 35 semanas ou mais e peso superior a 2000g com indicação para fototerapia. Os polimorfismos nos genes SLCO1B1 (rs4149056 e rs2306283) e SLCO1B3 (rs17680137 e rs2117032) foram analisados por sondas de hidrólise. Um total de 167 hiperbilirrubinêmicos e 247 recém-nascidos controles foi arrolado. Sexo, incompatibilidade ABO, peso ao nascimento e idade gestacional diferiram entre os grupos, mas as frequências alélicas e genotípicas dos polimorfismos dos genes SLCO1B não. Na análise por regressão logística, incompatibilidade ABO, idade gestacional e o alelo polimórfico T do rs2117032 permaneceram no modelo. A presença desse polimorfismo pareceu conferir proteção à hiperbilirrubinemia. Os indivíduos que eram homozigotos para o alelo G do rs2306283 e deficientes da enzima glicose-6-fosfato desidrogenase eram mais frequentes entre os casos. No presente estudo foram observadas apenas fracas interações entre os diferentes polimorfismos e os fatores clínico-ambientais. / Jaundice usually is a physiological phenomenon among newborns; however, severe hyperbilirubinemia occurs in 5% to 6% of this population. It has been suggested that genetic variation in the genes of bilirubin transporters could enhance the risk of hyperbilirubinemia when co-expressed with other icterogenic conditions. The present study included newborns with a gestational age of greater than 35 weeks and weights greater than 2000 g with indications for phototherapy. The polymorphisms from SLCO1B1 (rs4149056 and rs2306283) and SLCO1B3 (rs17680137 and rs2117032) genes were analyzed by hydrolysis probes. A total of 167 hyperbilirubinemic infants and 247 control subjects were enrolled. The gender, ABO incompatibility, birth weight, and gestational age differed between the groups but the allelic and genotypic frequency of the polymorphisms from SLCO1B genes did not. In logistic regression, the ABO incompatibility, gestational age, and polymorphic T allele of rs2117032 remained in the model. The presence of this polymorphism seemed to provide protection from hyperbilirubinemia. The individuals that were homozygous for the G allele of rs2306283 and glucose 6-phosphate-dehydrogenase deficient were more frequent among the cases. In the present study there were observed only weak associations between the different polymorphisms and the clinical/environmental factors.

A icterícia costuma ser um fenômeno fisiológico em recém-nascidos saudáveis, contudo, hiperbilirrubinemia não conjugada grave ocorre em 5 a 6% dessa população. Tem sido sugerido que a variabilidade genética de genes de proteínas transportadoras de bilirrubina poderia aumentar o risco de hiperbilirrubinemia quando associada a outros fatores icterogênicos. O presente estudo incluiu neonatos com idade gestacional de 35 semanas ou mais e peso superior a 2000g com indicação para fototerapia. Os polimorfismos nos genes SLCO1B1 (rs4149056 e rs2306283) e SLCO1B3 (rs17680137 e rs2117032) foram analisados por sondas de hidrólise. Um total de 167 hiperbilirrubinêmicos e 247 recém-nascidos controles foi arrolado. Sexo, incompatibilidade ABO, peso ao nascimento e idade gestacional diferiram entre os grupos, mas as frequências alélicas e genotípicas dos polimorfismos dos genes SLCO1B não. Na análise por regressão logística, incompatibilidade ABO, idade gestacional e o alelo polimórfico T do rs2117032 permaneceram no modelo. A presença desse polimorfismo pareceu conferir proteção à hiperbilirrubinemia. Os indivíduos que eram homozigotos para o alelo G do rs2306283 e deficientes da enzima glicose-6-fosfato desidrogenase eram mais frequentes entre os casos. No presente estudo foram observadas apenas fracas interações entre os diferentes polimorfismos e os fatores clínico-ambientais. / Jaundice usually is a physiological phenomenon among newborns; however, severe hyperbilirubinemia occurs in 5% to 6% of this population. It has been suggested that genetic variation in the genes of bilirubin transporters could enhance the risk of hyperbilirubinemia when co-expressed with other icterogenic conditions. The present study included newborns with a gestational age of greater than 35 weeks and weights greater than 2000 g with indications for phototherapy. The polymorphisms from SLCO1B1 (rs4149056 and rs2306283) and SLCO1B3 (rs17680137 and rs2117032) genes were analyzed by hydrolysis probes. A total of 167 hyperbilirubinemic infants and 247 control subjects were enrolled. The gender, ABO incompatibility, birth weight, and gestational age differed between the groups but the allelic and genotypic frequency of the polymorphisms from SLCO1B genes did not. In logistic regression, the ABO incompatibility, gestational age, and polymorphic T allele of rs2117032 remained in the model. The presence of this polymorphism seemed to provide protection from hyperbilirubinemia. The individuals that were homozygous for the G allele of rs2306283 and glucose 6-phosphate-dehydrogenase deficient were more frequent among the cases. In the present study there were observed only weak associations between the different polymorphisms and the clinical/environmental factors.

A icterícia costuma ser um fenômeno fisiológico em recém-nascidos saudáveis, contudo, hiperbilirrubinemia não conjugada grave ocorre em 5 a 6% dessa população. Tem sido sugerido que a variabilidade genética de genes de proteínas transportadoras de bilirrubina poderia aumentar o risco de hiperbilirrubinemia quando associada a outros fatores icterogênicos. O presente estudo incluiu neonatos com idade gestacional de 35 semanas ou mais e peso superior a 2000g com indicação para fototerapia. Os polimorfismos nos genes SLCO1B1 (rs4149056 e rs2306283) e SLCO1B3 (rs17680137 e rs2117032) foram analisados por sondas de hidrólise. Um total de 167 hiperbilirrubinêmicos e 247 recém-nascidos controles foi arrolado. Sexo, incompatibilidade ABO, peso ao nascimento e idade gestacional diferiram entre os grupos, mas as frequências alélicas e genotípicas dos polimorfismos dos genes SLCO1B não. Na análise por regressão logística, incompatibilidade ABO, idade gestacional e o alelo polimórfico T do rs2117032 permaneceram no modelo. A presença desse polimorfismo pareceu conferir proteção à hiperbilirrubinemia. Os indivíduos que eram homozigotos para o alelo G do rs2306283 e deficientes da enzima glicose-6-fosfato desidrogenase eram mais frequentes entre os casos. No presente estudo foram observadas apenas fracas interações entre os diferentes polimorfismos e os fatores clínico-ambientais. / Jaundice usually is a physiological phenomenon among newborns; however, severe hyperbilirubinemia occurs in 5% to 6% of this population. It has been suggested that genetic variation in the genes of bilirubin transporters could enhance the risk of hyperbilirubinemia when co-expressed with other icterogenic conditions. The present study included newborns with a gestational age of greater than 35 weeks and weights greater than 2000 g with indications for phototherapy. The polymorphisms from SLCO1B1 (rs4149056 and rs2306283) and SLCO1B3 (rs17680137 and rs2117032) genes were analyzed by hydrolysis probes. A total of 167 hyperbilirubinemic infants and 247 control subjects were enrolled. The gender, ABO incompatibility, birth weight, and gestational age differed between the groups but the allelic and genotypic frequency of the polymorphisms from SLCO1B genes did not. In logistic regression, the ABO incompatibility, gestational age, and polymorphic T allele of rs2117032 remained in the model. The presence of this polymorphism seemed to provide protection from hyperbilirubinemia. The individuals that were homozygous for the G allele of rs2306283 and glucose 6-phosphate-dehydrogenase deficient were more frequent among the cases. In the present study there were observed only weak associations between the different polymorphisms and the clinical/environmental factors.

No description available.

Drug transport across cells and cell membranes in the human body is crucial for the pharmacological effect of drugs. Active transport governed by transport proteins plays an important role in this process. A vast number of transport proteins with a wide tissue distribution have been identified during the last 15 years. Several important examples of their role in drug disposition and drug-drug interactions have been described to date. Investigation of drug-drug interactions at the transport protein level are therefore of increasing interest to the academic, industrial and regulatory research communities. The gene expression of transport proteins involved in drug transport was investigated in the jejunum, liver, kidney and colon to better understand their influence on the ADMET properties of drugs. In addition, the gene and protein expression of transport proteins in cell lines, widely used for predictions of drug transport and metabolism, was examined. The substrate and inhibitor heterogeneity of many transport proteins makes it difficult to foresee whether the transport proteins will cause drug-drug interactions. Therefore, in vitro assays for OCT1 and OATP1B1, among the highest expressed transport proteins in human liver, were developed to allow investigation of the inhibitory patterns of these proteins. These assays were used to investigate two data sets, consisting of 191 and 135 registered drugs and drug-like molecules for the inhibition of OCT1 and OATP1B1, respectively. Numerous new inhibitors of the transport proteins were identified in the data sets and the properties governing inhibition were determined. Further, antidepressant drugs and statins displayed strong inhibition of OCT1 and OATP1B1, respectively. The inhibition data was used to develop predictive in silico models for each of the two transport proteins. The highly polymorphic nature of some transport proteins has been shown to affect drug response and may lead to an increased risk of drug-drug interactions, and therefore, the OCT1 in vitro assay was used to study the effect of common genetic variants of OCT1 on drug inhibition and drug-drug interactions. The results indicated that OCT1 variants with reduced function were more susceptible to inhibition. Further, a drug-drug interaction of potential clinical significance in the genetic OCT1 variant M420del was proposed. In summary, gene expression of transport proteins was investigated in human tissues and cell lines. In vitro assays for two of the highest expressed liver transport proteins were used to identify previously unknown SLC transport protein inhibitors and to develop predictive in silico models, which may detect previously known drug-drug interactions and enable new ones to be identified at the transport protein level. In addition, the effect of genetic variation on inhibition of the OCT1 was investigated.