ABSTRACT
Objective:To investigate the effect and mechanism of tumor necrosis factor α (TNF-α) and its inhibitor etanercept (ETA) on the invasion ability of extravillous trophoblast in patients with unexplained recurrent spontaneous abortion (URSA).Methods:(1) Patients were collected from March to June in 2019. They were divided into the URSA group ( n=15) and the normal control group ( n=15), according to whether diagnosed with URSA or not. The mRNA expression levels of TNF-α in villi tissue of patients in the two groups were detected by quantitative real-time PCR (qRT-PCR). (2) The mRNA and protein expression levels of matrix metalloproteinase-2 (MMP-2), Slug and CXC chemokine rceptor 4 (CXCR4) in HTR-8/SVneo cells were detected by qRT-PCR or western blot after being stimulated by exogenous TNF-α (0.2, 2, 20 ng/ml) alone or TNF-α along with ETA, or phosphate buffered saline (PBS) as control. (3) The invasion ability of HTR-8/SVneo cells was investigated by transwell test after stimulating by TNF-α alone or TNF-α along with ETA. (4) The mRNA and protein expression levels of MMP-2, Slug and CXCR4 in HTR-8/SVneo cells, which were stimulated by TNF-α (2 ng/ml) alone after nuclear factor-κB (NF-κB) inhibitor, BAY 11-7028, preconditioning, were detected by qRT-PCR or western blot. Results:(1) The mRNA expression level of TNF-α in villi tissue of URSA group (4.10±0.49) was 4.1 times as much as the normal control group ( t=10.51, P<0.05). (2) The mRNA and protein expression levels of MMP-2, Slug and CXCR4 in HTR-8/SVneo cells of TNF-α group were significantly lower than those in PBS control group ( P<0.05) and those in TNF-α along with ETA group ( P<0.05). (3) The invasion ability of HTR-8/SVneo cells in TNF-α group was significantly decreased than PBS group and TNF-α along with ETA group (78±14 vs 373±26 vs 227±44, P<0.05). (4) The mRNA and protein expression levels of MMP-2, Slug and CXCR4 in HTR-8/SVneo cells with BAY 11-7028 preconditioning (mRNA: 1.03±0.10, 1.03±0.06, 1.09±0.08; protein: 1.09±0.03, 1.49±0.03, 1.12±0.03) were significantly higher than without preconditioning after being stimulated by TNF-α (all P<0.05). Conclusions:The expression of TNF-α in the villi of URSA patients is much higher than normal early pregnant women. TNF-α could decrease the capacity of invasion by suppressing the expression of MMP-2, Slug and CXCR4 through NF-κB signaling pathway in extravillous trophoblast cells. While ETA could improve the invasiveness capability of extravillous trophoblast cells through inhibiting the negative effect of TNF-α.
ABSTRACT
BACKGROUND: Membrane CD36 is a fatty acid transporter implicated in the pathogenesis of metabolic disease. We aimed to evaluate the association between plasma CD36 levels and diabetes risk and to examine if the association was independent of adiposity among Danish population.METHODS: We conducted a case-cohort study nested within the Danish Diet, Cancer and Health study among participants free of cardiovascular disease, diabetes and cancer and with blood samples and anthropometric measurements (height, weight, waist circumference, and body fat percentage) at baseline (1993 to 1997). CD36 levels were measured in 647 incident diabetes cases that occurred before December 2011 and a total of 3,515 case-cohort participants (236 cases overlap).RESULTS: Higher plasma CD36 levels were associated with higher diabetes risk after adjusting for age, sex and other lifestyle factors. The hazard ratio (HR) comparing high versus low tertile of plasma CD36 levels was 1.36 (95% confidence interval [CI], 1.00 to 1.86). However, the association lost its significance after further adjustment for different adiposity indices such as body mass index (HR, 1.23; 95% CI, 0.87 to 1.73), waist circumference (HR, 1.21; 95% CI, 0.88 to 1.68) or body fat percentage (HR, 1.20; 95% CI, 0.86 to 1.66). Moreover, raised plasma CD36 levels were moderately associated with diabetes risk among lean participants, but the association was not present among overweight/obese individuals.CONCLUSION: Higher plasma CD36 levels were associated with higher diabetes risk, but the association was not independent of adiposity. In this Danish population, the association of CD36 with diabetes risk could be either mediated or confounded by adiposity.