Exercises down regulate Toll-like receptor 4 signaling pathway in obese and overweight pregnant women / 中华围产医学杂志

ABSTRACT

Objective:To explore the effect of exercise intervention on regulation of Toll-like receptor 4 (TLR4) signaling pathway in overweight and obese pregnant women.Methods:The cohort was based on a randomized controlled trial (RCT) carried out by the same research group in Peking University First Hospital from December 2014 to July 2016. Overweight and obese patients who delivered by elective cesarean section without pregnancy complications were recruited, among which 12 cases in the exercise group and 11 cases in the control group were selected. Real-time polymerase chain reaction, Western Blot, and Luminex experiments were used to compare the expression of TLR4-myeloid differentiation factor 8(MyD88)-nuclear factor-κB(NF-κB) pathway in peripheral blood mononuclear cell (PBMC), rectus abdominis muscle, omental adipose, and subcutaneous adipose, as well as the levels of inflammatory factors (TNF-α, IL-1β, IL-10) in plasma between the two groups. Two independent samples t-test, generalized estimating equation, Chi-square test, and Pearson correlation analysis were adopted for statistical analysis. Results:(1) The expression of inflammatory factors TNF-α and IL-1β in the exercise group showed a downward trend compared with the control in the second and third trimester, but none of the differences were statistically significant (all P>0.05). (2) The mRNA expression of TLR4, MyD88, and NF-κB and the protein expression of TLR4 and NF-κB in PBMC of the exercise group were significantly lower than those in the control group during pregnancy (TLR4 mRNA 0.06±0.03 vs 0.10±0.04 in the second trimester, 0.05±0.02 vs 0.11±0.05 in the third trimester, χ2=8.07; MyD88 mRNA 0.09±0.03 vs 0.11±0.03 in the second trimester, 0.10±0.04 vs 0.17±0.06 in the third trimester, χ2=5.81; NF-κB mRNA 0.10±0.03 vs 0.17±0.08 in the second trimester, 0.08±0.03 vs 0.20±0.08 in the third trimester, χ2=14.71; TLR4 protein 1.7±0.5 vs 1.9±0.8 in the second trimester, 1.7±0.4 vs 2.3±0.8 in the third trimester, χ2=5.83; NF-κB protein 1.0±0.4 vs 1.5±0.4 in the second trimester, 1.2±0.3 vs 1.5±0.5 in the third trimester, χ2=4.73; all P<0.05). Moreover, the differences in the mRNA expression of TLR4, MyD88, and NF-κB and TLR4 protein expression in PBMC between the two groups gradually increased. (3) NF-κB in rectus abdominis and omental adipose tissue (0.04±0.02 vs 0.08±0.04, t=－3.72; 0.25±0.05 vs 0.63±0.21, t=－5.41; both P<0.05) and TLR4 and MyD88 in subcutaneous adipose tissue (0.12±0.03 vs 0.30±0.10, t=－5.30; 0.24±0.09 vs 0.44±0.08, t=－5.38; both P<0.05) were observed a decreased mRNA level in the exercise group compared with the control group. The protein level of MyD88 and NF-κB in omental adipose tissue and NF-κB in subcutaneous adipose tissue in the exercise group were significantly lower than those in the control group (1.1±0.5 vs 2.0±0.8, t=－3.15; 1.3±0.5 vs 2.0±0.9, t=－2.23; 1.2±0.5 vs 1.9±0.8, t=－2.80, all P<0.05). (4) The expressions of TLR4 and NF-κB mRNA ( r=0.453 and 0.485) in rectus abdominis muscle, NF-κB mRNA, TLR4 and MyD88 protein ( r=0.539, 0.437 and 0.527) in omental adipose in the two groups were positively correlated with the level of fasting blood glucose ( P<0.05). Conclusions:Regular exercise during pregnancy can down-regulate the expression and activation of the TLR4-MyD88-NFκB pathway in overweight and obese pregnant women. The expression of related factors along this pathway has a certain correlation with fasting blood glucose.