RESUMO
Lumbar-disc degeneration (LDD) is a polygenic disease. Susceptibility genes reported so far are mainly extracellular matrix proteins. D14 allele of asporin (ASPN) is associated with osteoarthritis (OA). Candidate-gene association studies showed that the D14 allele is also significantly associated with LDD in Chinese and Japanese individuals. Meta-analysis showed that individuals harboring a D14 allele had higher risk with a summary odds ratio of 1.70 (p = 0.000013). ASPN expression in vertebral discs increased with age and degeneration. Our results indicate ASPN is a LDD gene in Asians, and common risk factors may be considered for OA and LDD.
Assuntos
Povo Asiático/genética , Proteínas da Matriz Extracelular/genética , Predisposição Genética para Doença , Disco Intervertebral , Vértebras Lombares , Osteocondrite/genética , Adolescente , Adulto , Alelos , Ácido Aspártico/química , Ácido Aspártico/genética , Proteínas da Matriz Extracelular/química , Feminino , Frequência do Gene , Humanos , Masculino , Pessoa de Meia-Idade , Osteoartrite/genética , Polimorfismo Genético , Sequências Repetitivas de Aminoácidos/genéticaRESUMO
This study investigated the expression profile of placental leptin and leptin receptor isoforms in preeclampsia, using placental tissue from normal pregnancies that were matched in gestational age and birth weight as controls. A total of 29 cases of preeclampsia were studied by immunohistochemistry, including 16 severe and 13 mild preeclampsia cases. Reverse transcriptase-polymerase chain reaction (RT-PCR) was further performed using RNA extracted from frozen tissue (10 severe preeclampsia, 10 mild preeclampsia, and 20 normal third trimester placentas). In all tissue sections, immunostaining signal was shown in the cytoplasmic compartment of the trophoblastic cells. Both the severe and mild preeclampsia groups showed significantly higher immunostaining for leptin compared with normal controls (p < 0.05), but there was no significant difference between the severe and mild preeclampsia groups (p > 0.05). There was no significant difference in immunostaining for leptin receptor between both severe and mild preeclampsia compared with controls (p > 0.05). RT-PCR showed significantly higher levels of mRNA transcripts of leptin in severe preeclampsia (p < 0.05), but not mild preeclampsia (p > 0.05), compared with normal controls. No significant difference in expression of all the receptor isoforms was demonstrated between both severe and mild preeclampsia groups compared with controls (p > 0.05). In conclusion, we confirmed an up-regulated expression of leptin in placental tissue in preeclampsia. However, there was no difference in the expression of all leptin receptor isoforms in placental tissue between preeclamptic and normal pregnancies. The leptin signal probably does not play a major primary role in the pathogenesis of preeclampsia.
