News and Events

News and Events

University of Louisville researchers show that chronic exposure to benzene causes insulin resistance in mice

Benzene exposure induces insulin resistance in mice

Wesley Abplanalp, PhD Nalinie S Wickramasinghe, PhD Srinivas D Sithu, PhDDaniel J Conklin, PhD Zhengzhi Xie, PhD Aruni Bhatnagar, PhD Sanjay Srivastava, PhDTimothy E O’Toole, PhD

Abstract

 

Benzene is a ubiquitous pollutant associated with hematotoxicity but its metabolic effects are unknown. We sought to determine if and how exposure to volatile benzene impacted glucose handling. We exposed wild type C57BL/6 mice to volatile benzene (50ppm x 6h/d) or HEPA-filtered air for 2 or 6wk and measured indices of oxidative stress, inflammation and insulin signaling. Compared to air controls, we found that mice inhaling benzene demonstrated increased plasma glucose (p = 0.05), insulin (p = 0.03), and HOMA-IR (p = 0.05), establishing a state of insulin and glucose intolerance. Moreover, insulin-stimulated Akt phosphorylation was diminished in the liver (p = 0.001) and skeletal muscle (p = 0.001) of benzene-exposed mice, accompanied by increases in oxidative stress and NF-κB phosphorylation (p = 0.025). Benzene-exposed mice also demonstrated elevated levels of MIP1-α transcripts and SOCS1 (p = 0.001), but lower levels of IRS-2 tyrosine phosphorylation (p = 0.0001). Treatment with the superoxide dismutase mimetic, TEMPOL, reversed benzene-induced effects on oxidative stress, NF-κB phosphorylation, SOCS1 expression, IRS-2 tyrosine phosphorylation, and systemic glucose intolerance. These findings suggest that exposure to benzene induces insulin resistance and that this may be a sensitive indicator of inhaled benzene toxicity. Persistent ambient benzene exposure may be a heretofore unrecognized contributor to the global human epidemics of diabetes and cardiovascular disease. Tox Sci, 2018 (in press)

 

 

Superfund Research Program Administrator visits the UofL Superfund Research Center

NIEHS Superfund Research Program Administrator Dr. Danielle Carlin visits our Center November 5, 2018.

UofL Superfund Researchers attend the Annual Superfund Research Program Meeting 2018

Many of the University of Louisville Superfund Research Center members attended the Superfund Research Program Annual Meeting in Sacramento, California November 28th-30th.  This is always a great opportunity for our center to learn what other researchers from programs all over the country are doing to study the affects of hazardous chemicals found at other Superfund Sites.  The Superfund Research Centers at UC Davis, along with UC Berkeley and UC Diego is hosting this meeting.  This year's theme was “The Next Generation of Superfund Training, Translation and Research”. "A major objective of the meeting is to highlight innovation occurring within SRP centers to promote environmental health, particularly that being driven by early stage investigators and trainees". For more information about this meeting see the SRP's meeting website