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Studies have shown that maternal exposure to PM2.5 could potentially disrupt glucose and lipid metabolism in offspring supplied with high-fat diet, yet whether this effect is gender-dependent or not and the underlying biological mechanisms are not well understood. In our current research, female ICR mice were exposed to filtered air (FA) or concentrated ambient PM2.5 (CAP) before and during pregnancy. The offspring mice were fed with control diet (CD) or high-fat diet (HFD) for 9 weeks, and their metabolic conditions were analyzed. Our findings reveal that maternal exposure to PM2.5 induced glucose intolerance and insulin resistance in female offspring fed with HFD but not in males. Specifically, hepatic insulin resistance as indicated by significantly decreased AKT phosphorylation (p-AKT) level, changed liver structure as indicated by increased ballooning and steatosis based on H&E staining images, and impaired liver function as indicated by up-regulated ALT activity were observed in HFD-fed female offspring from CAP-exposed mothers in comparison to those from FA-exposed ones. Further analysis indicated that these impacts of prenatal PM2.5 exposure on glucose metabolism in offspring may result from disturbed gluconeogenesis and induced inflammatory response in liver. Our research underscores that prenatal PM2.5 exposure induces glucose metabolism abnormalities in offspring fed with HFD in a gender-dependent manner, and the liver potentially serves as a key player in mediating these effects of maternal PM2.5 exposure.

Background: Previous studies found that urinary phthalates (PAEs) metabolites may be associated with increased serum uric acid concentration and hyperuricemia risk. However, no population-based study has investigated the underlying biological mechanisms. Methods: This nationwide cross-sectional study analyzed the data from the National Health and Nutrition Examination Survey (NHANES) 2003–2018. Urinary PAEs metabolites were measured and 8 PAEs metabolites (MCPP, MECPP, MEHHP, MEOHP, MBzP, MiBP, MBP, and MEP) were incorporated into the analysis. Serum uric acid was determined and hyperuricemia cases were identified. Multi-variable generalized linear model, exposure-response (E-R) function and weighted quantile sum (WQS) regression were utilized to investigate the relationships of PAEs metabolites with serum uric acid concentration and hyperuricemia risk. Systemic immune inflammation (SII) was assessed using the SII index and its mediation effects were explored using causal mediation effect model. Results: Data from 10,633 US adults in the NHANES 2003–2018 was analyzed. Except for MEP, individual PAEs metabolite and total PAEs metabolites were associated with increased serum uric acid concentration and hyperuricemia risk. E-R function of PAEs metabolites with serum uric acid concentration and the risk of hyperuricemia showed significantly positive associations with most curves in a nearly linear relationship. WQS regression showed that the mixture of PAEs metabolites was related to elevated serum uric acid and hyperuricemia risk, and MBzP was identified as the most contributing PAEs metabolite. The causal mediation effect model found that SII significantly mediated the relationships of PAEs metabolites with serum uric acid and hyperuricemia risk. Conclusion: Individual and mixture of urinary PAEs metabolites were associated with increased serum uric acid concentration and the risk of hyperuricemia. MBzP exhibited the highest contribution to the overall effects. SII alteration may be an important biological mechanism underlining the impact of PAEs metabolites on serum uric acid concentration and hyperuricemia risk.

Air pollution is one of the most important environmental issues in China and worldwide, as well as a critical public health problem affecting human health. With the implementation of emission reduction and other programs, the air quality in China has been improved dramatically in recent years, but is still worse than the WHO guideline recommended levels. Numerous epidemiological and toxicological studies have shown that short-term or long-term exposure to air pollution is strongly associated with respiratory diseases, cardiovascular diseases, diabetes, and so forth, in which interleukin-6 (IL-6), a well-known inflammatory factor, may play an important role. Studies have found that IL-6 can bind to interleukin-6 receptor (IL-6R) , which leads to the recruiting and activation of glycoprotein 130, and then the formed IL-6/IL-6R/gp130 complex triggers the janus kinase/signal transducer and activator of transcription, Src homology-2 domain-containing protein tyrosine phosphatase-2/mitogen-activated protein kinase, and phosphatidylinositol 3-kinase/protein kinase B signaling pathways. All of these signaling pathways are found to be involved in a variety of physiopathological processes. In the present review, information about the IL-6 signaling pathway and its role in air pollution-induced adverse health effects was systematically reviewed, hoping to provide insights for the future prevention and control policies.

Background: Ambient fine particulate matter (PM2.5) exposure increases local and systemic interleukin-6 (IL-6). However, the pathogenic role of IL-6 signalling following PM2.5 exposure, particularly in the development of pulmonary dysfunction and abnormal glucose homeostasis, has hardly been investigated. Results: In the study, IL-6 receptor (IL-6R)-deficient (IL-6R-/-) and wildtype littermate (IL-6R+/+) mice were exposed to concentrated ambient PM2.5 (CAP) or filtered air (FA), and their pulmonary and metabolic responses to these exposures were analyzed. Our results demonstrated that IL-6R deficiency markedly alleviated PM2.5 exposure-induced increases in lung inflammatory markers including the inflammation score of histological analysis, the number of macrophages in bronchoalveolar lavage fluid (BALF), and mRNA expressions of TNFα, IL-1β and IL-6 and abnormalities in lung function test. However, IL-6R deficiency did not reduce the hepatic insulin resistance nor systemic glucose intolerance and insulin resistance induced by PM2.5 exposure. Conclusion: Our findings support the crucial role of IL-6 signalling in the development of pulmonary inflammation and dysfunction due to PM2.5 exposure but question the putative central role of pulmonary inflammation for the extra-pulmonary dysfunctions following PM2.5 exposure, providing a deep mechanistic insight into the pathogenesis caused by PM2.5 exposure.