Associations between maternal stressful life events experiences and risk of neural tube defects in offspring: a systematic review and meta-analysis.

OBJECTIVES: Multiple factors associated with neural tube defects (NTDs) risk have been identified, yet there is little evidence on the possible effects of maternal stressful life events. In this study, we aimed to investigate the association between stressful life events during the periconceptional period and risk of NTDs in offspring. METHODS: Relevant literature was searched in PubMed, Springer Link, ScienceDirect, and Cochrane Library up to July 2023. The pooled odds ratio (OR) and 95% confidence interval (CI) of NTDs risk with maternal stressful life events were estimated using a random effects model. Publication bias was assessed using Egger's regression asymmetry test and Begg's rank correlation test with Begg's funnel plot. RESULTS: Analysis results showed that mothers who experienced stressful life events during the periconceptional period were at greater risk of having NTDs offspring (OR: 1.37, 95% CI: 1.08-1.73) than those who did not. In subgroup analysis, the pooled OR was 1.37 (1.13-1.67) and 1.73 (0.36-8.32) for with and without adjusting for folic acid supplementation in each included study, while was 1.37 (1.13-1.67) and 1.64 (0.39-6.88) for exposure time of three months preconception until three months post conception and one year preconception until three months post conception, respectively. CONCLUSIONS: This study suggests that maternal stressful life events during the periconceptional period are significantly associated with higher NTDs risk in offspring. Tailored approaches for evaluating the risk and policy of NTDs among women of childbearing age should emphasize individual stressful experiences before and during early pregnancy.

Sphingomyelin synthase 2 (SMS2) deficiency attenuates LPS-induced lung injury.

Sphingomyelin synthase (SMS) catalyzes the synthesis of sphingomyelin (SM) and is required for maintenance of plasma membrane microdomain fluidity. Of the two isoforms of mammalian SMS, SMS1 is mostly present in the trans-Golgi apparatus, whereas SMS2 is predominantly found at the plasma membrane. SMS2 has a role in receptor mediated response to inflammation in macrophages, however, the role of SMS2 in vascular permeability, pulmonary edema, and lung injury have not been investigated. To define the role of SMS activation in lung injury, we utilized a lipopolysaccharide (LPS)-induced lung edema model. SMS activity was measured and correlated with the severity of lung injury. Within 4 h of LPS treatment, SMS activity was increased significantly and remained upregulated up to 24 h. Comparison of LPS-induced lung injury in SMS2 knockout (SMS2(-/-)) and wild-type littermate control mice showed that inflammation, cytokine induction, and lung injury were significantly inhibited in SMS2(-/-) mice. Our results suggest that a deficiency of SMS2 can diminish the extent of pulmonary edema and lung injury. Furthermore, we show that depletion of SMS2 was sufficient to decrease MAP kinase-JNK activation, severity of LPS-induced pulmonary neutrophil influx, and inflammation, suggesting a novel role of SMS2 activation in lung injury.