Inhibition of Human Sulfotransferases by Phthalate Monoesters.

Objective: This study aimed to investigate the inhibition of human important phase II metabolic enzyme sulfotransferases (SULTs) by phthalate monoesters, which are important metabolites of phthalate esters (PAEs). Method: Recombinant SULT-catalyzed metabolism of p-nitrophenol (PNP) was employed as the probe reactions of SULTs to investigate the inhibition of 8 kinds of phthalate monoesters towards SULT isoforms. An in vitro incubation system was utilized for preliminary screening, and 100 µM of phthalate monoesters was used. Inhibition kinetics were carried out to determine the inhibition of SULTs by phthalate monoesters. Result: Multiple phthalate monoesters have been demonstrated to exert strong inhibition potential towards SULT1A1, SULT1B1, and SULT1E1, and no significant inhibition of phthalate monoesters towards SULT1A3 was found. The activity of SULT1A1 was strongly inhibited by mono-hexyl phthalate (MHP), mono-octyl phthalate (MOP), mono-benzyl phthalate (MBZP), and mono-ethylhexyl phthalate (MEHP). Monobutyl phthalate (MBP), MHP, MOP, mono-cyclohexyl phthalate (MCHP), and MEHP significantly inhibited the activity of SULT1B1. MHP, MOP, and MEHP significantly inhibited the activity of SULT1E1. MOP was chosen as the representative phthalate monoester to determine the inhibition kinetic parameters (Ki) towards SULT1B1 and SULT1E1. The inhibition kinetic parameters (Ki) were calculated to be 2.23 µM for MOP-SULT1B1 and 5.54 µM for MOP-SULT1E1. In silico docking method was utilized to understand the inhibition mechanism of SULT1B1 by phthalate monoesters. Conclusions: All these information will be beneficial for understanding the risk of phthalate monoester exposure from a new perspective.

PDGF-D activation by macrophage-derived uPA promotes AngII-induced cardiac remodeling in obese mice.

Obesity-induced secretory disorder of adipose tissue-derived factors is important for cardiac damage. However, whether platelet-derived growth factor-D (PDGF-D), a newly identified adipokine, regulates cardiac remodeling in angiotensin II (AngII)-infused obese mice is unclear. Here, we found obesity induced PDGF-D expression in adipose tissue as well as more severe cardiac remodeling compared with control lean mice after AngII infusion. Adipocyte-specific PDGF-D knockout attenuated hypertensive cardiac remodeling in obese mice. Consistently, adipocyte-specific PDGF-D overexpression transgenic mice (PA-Tg) showed exacerbated cardiac remodeling after AngII infusion without high-fat diet treatment. Mechanistic studies indicated that AngII-stimulated macrophages produce urokinase plasminogen activator (uPA) that activates PDGF-D by splicing full-length PDGF-D into the active PDGF-DD. Moreover, bone marrow-specific uPA knockdown decreased active PDGF-DD levels in the heart and improved cardiac remodeling in HFD hypertensive mice. Together, our data provide for the first time a new interaction pattern between macrophage and adipocyte: that macrophage-derived uPA activates adipocyte-secreted PDGF-D, which finally accelerates AngII-induced cardiac remodeling in obese mice.

[Factors influencing the choice of atrial septal occluder for transcatheter closure of secundum atrial septal defects].

OBJECTIVE: To analyze factors influencing the choice of atrial septal occluder (ASO) for transcatheter closure of patients with secundum atrial septal defect (ASD). METHODS: A total of 1114 ASD patients [388 males, aged from 2 to 75 years, mean age (26.3 +/- 17.0) years] were enrolled. Patients were divided to adult (> 14 years, mean 34.4 years, n = 779) and child (< or = 14 years, mean 7.3 years, n = 335) groups. ASD size in different ultrasound cross-sections was determined by transthoracic echocardiography (TTE). ASO size was chosen on the basis of the maximum diameter of the defect (MD). Defect-shapes and rim lengths of ASD, the difference choice of ASO in the two groups were compared. RESULTS: MD of the defects ranged from 5 to 40 mm [mean (19.7 +/- 7.8) mm]. ASD was successfully occluded in 1085 out of 1114 patients (97.4%). Occluder size ranged from 6 to 46 mm [mean (25.8 +/- 8.9) mm] and the difference between occluder size and MD ranged from 2 to 10 mm [mean (6.1 +/- 3.4) mm, ASO/MD ratio 1.3:1]. Though the diameter of the defect was similar between the 2 groups, the size of occluder was significantly larger in adult group than that in child group (ASO/MD ratio 1.1 - 1.6:1 vs. 1.2 - 1.8:1, P < 0.05). MD was significantly correlated with ASO in both groups (r = 0.911 and r = 0.944 in adults and child groups, respectively, all P < 0.01). The size and increment of the occluder used in patients with deficient anterior rims was significantly bigger than patients with sufficient anterior rims (P < 0.01). CONCLUSION: The maximum diameter of the defect was the major determinant for selecting occluder size and choice of occluder size was also influenced by patient age, defect-shape and defect rim for transcatheter closure of secundum ASD.