In collaboration with Boldogh, Srivastava next investigated whether aldose reductase inhibitors could reduce the asthma-like symptoms of mice exposed to ragweed extract, a well-established clinical model mimicking the allergic airway inflammation that commonly leads to asthma in humans. When untreated mice inhaled ragweed extract, their lungs suffered an influx of eosinophils (inflammation-inducing white blood cells), a jump in inflammatory signaling molecules, a buildup of mucin (a protein component of mucus) and an increase in airway hyper-reactivity (the tendency of air passages to suddenly constrict under stress). Mice fed a dose of aldose reductase inhibitor before inhaling ragweed extract, however, showed dramatically reduced levels of these components of the asthmatic response.

"Our hypothesis performed exactly as expected, with the experiments showing that aldose reductase is an essential enzyme in the transduction pathways that cause the transcription of the cytokines and chemokines known to act in asthma pathogenesis," Srivastava said. "They attract eosinophils and cause inflammation and mucin production in the airway."

The next step, Srivastava said, will be clinical trials to determine whether aldose reductase inhibitors can relieve asthma in humans. The researcher expressed optimism about their potential outcome of the trials, as well as gratitude to the UTMB National Institute of Environmental Health Sciences Center and the sole supporter of his asthma work, the American Asthma Foundation, which last year awarded him a three-year $750,000 research grant.

"Really, a lot of the credit for this belongs to the AAF," Srivastava said. "Our primary interest is in cancer and the secondary complications of diabetes, but we were attracted to asthma pathogenesis because the AAF invited me to apply for a grant. I think they're going to be happy with the results." 

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