Adverse effects of air pollutant exposure on blood lipid levels in adults: A systematic review and meta-analysis

Cardiovascular benefits of air purifier in patients with stable coronary artery disease: A randomized single-blind crossover study

Background

Exposure to PM_2.5 will accelerate the progression of cardiovascular diseases. Air purifier can reduce the PM_2.5 exposure and theoretically alleviate the influence of PM_2.5 on patients with stable coronary artery disease (SCAD). However, few studies of the protective effect showed significant results because the interferent effects of routine medication had not been taken into account. In order to explore the actual effect on patients with SCAD, we conducted a randomized single-blind crossover air purifier intervention trial.

Method

Levels of PM_2.5 exposure during intervention and cardiovascular indicators (inflammation, coagulation, plaque stability, and blood lipids) after intervention were detected, meanwhile the information of drug use was obtained by questionnaire. The kinds of drug used by more than 20% of the subjects were sorted out. And the influence of these drugs on cardiovascular indicators was summarized through literature review. Based on that, the drug use was included as a variable in linear mixed effects models that used to analyze the associations between PM_2.5 exposure reduction by air purifier and cardiovascular indicators.

Results

The result revealed that the interpretation contribution rate of drug use was more than that of PM_2.5 exposure. The level of C-reactive protein significantly decreased by 20.93% (95%CI: 6.56%, 33.10%), 23.44% (95%CI: 2.77%, 39.39%) and 24.11% (95%CI: 4.21%, 39.69%) on lag1, lag01 and lag02 respectively, while the level of high-density lipoprotein cholesterol significantly increased by 5.10% (95%CI: 0.69%, 9.05%), 3.71% (95%CI: 0.92%, 6.60%) and 6.48% (95%CI: 2.58%, 10.24%) respectively on lag0, lag1 and lag01 associated with an interquartile range decrease of 22.51 μg/m³ in PM_2.5 exposure.

Conclusion

The study shows positive effects of air purifier on SCAD, and also provides methodological reference for future related research.

Characterization of plasma-derived exosomal miRNA changes following traffic-related air pollution exposure: A randomized, crossover trial based on small RNA sequencing

BACKGROUND

The underlying mechanisms for health effects of traffic-related air pollution (TRAP) are still unclear. Small RNA sequencing (RNA-seq) in exosomes represents as a powerful approach to elucidate biological pathways in response to environmental exposure. We therefore aimed to explore impact of TRAP exposure on exosomal miRNAs.

METHODS

We performed a randomized, crossover study among 35 healthy college students in Shanghai, China. Participants were randomly assigned to 4-hour exposure in a traffic-polluted Road and in a traffic-free Park, respectively, intermitted by a washout period (at least 2 weeks). RNA-seq was conducted to identify plasma-derived exosomal miRNAs and the differential miRNAs were explored using linear mixed-effect models. Pathway enrichment was conducted using ingenuity pathway analysis. Further, we validated several selected miRNAs by droplet digital PCR (ddPCR).

RESULTS

The average concentrations of air pollutants including ultrafine particles, black carbon, nitrogen dioxide, and carbon dioxide were 2-3 times higher in the Road compared to those in the Park. We identified 271 exosomal miRNAs (212 up-regulated and 59 down-regulated) that were significantly associated with TRAP. We found 5 miRNAs with 242 experimentally validated mRNA targets that were involved in cardiovascular pathway, cytokine signaling, and immune response. The ddPCR analysis suggested that miR-3612, miR-21-5p, and miR-195-5p were significantly changed following TRAP exposure.

CONCLUSIONS

For the first time this trial characterized the genome-wide changes of exosomal miRNA associated with TRAP exposure. The molecular profiling of exosomal miRNAs and "novel" associations of some miRNAs were useful for understanding on biological mechanisms for the adverse effects of TRAP.

Impacts of Environmental Insults on Cardiovascular Aging

PURPOSE OF REVIEW

With cardiovascular disease (CVD) being the top cause of deaths worldwide, it is important to ensure healthy cardiovascular aging through enhanced understanding and prevention of adverse health effects exerted by external factors. This review aims to provide an updated understanding of environmental influences on cardiovascular aging, by summarizing epidemiological and mechanistic evidence for the cardiovascular health impact of major environmental stressors, including air pollution, endocrine-disrupting chemicals (EDCs), metals, and climate change.

RECENT FINDINGS

Recent studies generally support positive associations of exposure to multiple chemical environmental stressors (air pollution, EDCs, toxic metals) and extreme temperatures with increased risks of cardiovascular mortality and morbidity in the population. Environmental stressors have also been associated with a number of cardiovascular aging-related subclinical changes including biomarkers in the population, which are supported by evidence from relevant experimental studies. The elderly and patients are the most vulnerable demographic groups to majority environmental stressors. Future studies should account for the totality of individuals' exposome in addition to single chemical pollutants or environmental factors. Specific factors most responsible for the observed health effects related to cardiovascular aging remain to be elucidated.