828: Screening of lysyl oxidase (LOX) and lysyl oxidase-like (LOXL) enzyme expression and activity in human fetal membranes

ObjectiveLysyl oxidase (LOX) and LOX like enzymes (LOXL 1-4) are required for extracellular matrix remodeling through elastin and collagen crosslinking during pregnancy. In addition, LOX and LOXL are involved in cellular senescence under oxidative stress (OS). The objective of this study is to characterize the role of LOX and LOXL in human fetal membranes.Study DesignLOX and LOXL (1-4) expression and localization in human fetal membranes collected from women with uncomplicated pregnancies at term, preterm birth (PTB) with intact membranes or preterm premature rupture of membranes (pPROM), and in membranes maintained in an organ explant system stimulated with water soluble cigarette smoke extract (wsCSE) and wsCSE + N-Acetylcysteine (NAC) were documented by real time PCR and immunohistochemistry. LOX activity was measured by fluorometeric assay.ResultsLOX gene expression was ∼ 2.5-fold higher in pPROM compared to term and PTB (p=0.02) (Figure 1A). Membranes expressed all LOXL isoforms with no significant differences in their expressions among clinical samples. LOX and LOXL1, 2 and 4 were localized to both amniotic and chorionic cells, whereas LOXL3 was limited to chorion. LOX expression was decreased by half in wsCSE compared to control, and its expression was increased after NAC treatment (Figure 1A). The LOXL isoforms expressions were not different between treated and untreated groups. The wsCSE treatment reduced intracellular LOX activity, while the treatment with antioxidant NAC resulted in a 3-fold increase in secreted LOX activity (p=0.002) (Figure 1B).Conclusion ObjectiveLysyl oxidase (LOX) and LOX like enzymes (LOXL 1-4) are required for extracellular matrix remodeling through elastin and collagen crosslinking during pregnancy. In addition, LOX and LOXL are involved in cellular senescence under oxidative stress (OS). The objective of this study is to characterize the role of LOX and LOXL in human fetal membranes. Lysyl oxidase (LOX) and LOX like enzymes (LOXL 1-4) are required for extracellular matrix remodeling through elastin and collagen crosslinking during pregnancy. In addition, LOX and LOXL are involved in cellular senescence under oxidative stress (OS). The objective of this study is to characterize the role of LOX and LOXL in human fetal membranes. Study DesignLOX and LOXL (1-4) expression and localization in human fetal membranes collected from women with uncomplicated pregnancies at term, preterm birth (PTB) with intact membranes or preterm premature rupture of membranes (pPROM), and in membranes maintained in an organ explant system stimulated with water soluble cigarette smoke extract (wsCSE) and wsCSE + N-Acetylcysteine (NAC) were documented by real time PCR and immunohistochemistry. LOX activity was measured by fluorometeric assay. LOX and LOXL (1-4) expression and localization in human fetal membranes collected from women with uncomplicated pregnancies at term, preterm birth (PTB) with intact membranes or preterm premature rupture of membranes (pPROM), and in membranes maintained in an organ explant system stimulated with water soluble cigarette smoke extract (wsCSE) and wsCSE + N-Acetylcysteine (NAC) were documented by real time PCR and immunohistochemistry. LOX activity was measured by fluorometeric assay. ResultsLOX gene expression was ∼ 2.5-fold higher in pPROM compared to term and PTB (p=0.02) (Figure 1A). Membranes expressed all LOXL isoforms with no significant differences in their expressions among clinical samples. LOX and LOXL1, 2 and 4 were localized to both amniotic and chorionic cells, whereas LOXL3 was limited to chorion. LOX expression was decreased by half in wsCSE compared to control, and its expression was increased after NAC treatment (Figure 1A). The LOXL isoforms expressions were not different between treated and untreated groups. The wsCSE treatment reduced intracellular LOX activity, while the treatment with antioxidant NAC resulted in a 3-fold increase in secreted LOX activity (p=0.002) (Figure 1B). LOX gene expression was ∼ 2.5-fold higher in pPROM compared to term and PTB (p=0.02) (Figure 1A). Membranes expressed all LOXL isoforms with no significant differences in their expressions among clinical samples. LOX and LOXL1, 2 and 4 were localized to both amniotic and chorionic cells, whereas LOXL3 was limited to chorion. LOX expression was decreased by half in wsCSE compared to control, and its expression was increased after NAC treatment (Figure 1A). The LOXL isoforms expressions were not different between treated and untreated groups. The wsCSE treatment reduced intracellular LOX activity, while the treatment with antioxidant NAC resulted in a 3-fold increase in secreted LOX activity (p=0.002) (Figure 1B). Conclusion