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LancePodstrong [soylentnews.org] writes:

Because of undetected toxicity problems, about a third of prescription drugs approved in the U.S. are withdrawn from the market or require added warning labels limiting their use. An exceptionally sensitive toxicity test invented at the University of Utah could make it possible to uncover more of these dangerous side effects early in pharmaceutical development so that fewer patients are given unsafe drugs.
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The key to the test's sensitivity is the way it uses untamed house mice -- rather than docile, inbred laboratory strains -- and subjects them to a relentless, Darwinian competition for food, shelter and mates much like they would face in the wild. Mice jostle and race for a place in a roughly 300-square-foot pen divided into six territories by wire fencing that individuals must climb to invade or flee neighboring turf. Four of the territories are prime real estate with multiple hidden nesting sites and direct access to feeders. Two territories are poor, offering only open nesting sites and indirect feeder access. The test is called the organismal performance assay, or OPA.

Potts first came up with the idea as a way to explore the impact of inbreeding. Those studies revealed harmful effects of cousin-level inbreeding that had gone unnoticed for decades of research on mouse genetics. Laboratory mice that are only slightly less healthy may not appear so when given ample food and living space. But if there is a defect in any physiological system, it is likely to stand out during intense competition.
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In a study published last year, the performance assay revealed that doses of sugar that people regularly consume -- and deemed safe by regulators -- may in fact be toxic. When mice ate a diet of 25 percent extra sugar (the mouse equivalent of drinking three cans of soda daily) females died at twice the normal rate and males were a quarter less likely to hold territory and reproduce.
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In the Paxil study, the researchers gave food laced with the antidepressant to 20 breeding pairs of mice for several weeks, until all had produced up to four litters. Doses were equivalent to about 1.8 times the level typically prescribed for people. The offspring also ate Paxil-laced chow until they reached breeding age. The researchers then released the exposed offspring into the competitive arena with the offspring of a control group of mice never exposed to Paxil. Groups consisted of eight males and 14 to 16 females, creating population densities comparable to those seen in the wild. The researchers started five such populations and kept them going for six months.

Males exposed to Paxil were about half as likely to control a territory. They also lagged behind control males in body weight throughout the weeks of competition and were more likely to die. Exposed males produced 44 percent fewer offspring. Exposed females showed no significant weight or mortality differences, but they produced half as many offspring as control females at the initial assessment. Their fecundity rebounded at later time points.

This story is from December 14, 2014, but I just found out about it today. I found it fascinating and thought you might enjoy it too.

Original Submission