Posts tagged with "Centers for Disease Control"

Binge Drinking May be More Damaging to Women

Alcohol consumption is a major cause of chronic liver disease in the United States, and binge drinking is emerging as a significant contributor to liver injury. According to the Centers for Disease Control and Prevention, one in six U.S. adults binge drink four times per month. In a recently published study examining the effects of binge drinking on rats, researchers from the University of Missouri School of Medicine discovered that female rats who were of equal age and weight to male rats were more sensitive to alcohol and experienced alcoholic liver injury at a higher rate than male rats.

“Some chronic drinkers can drink for several years and still live relatively healthy lives,” said Shivendra Shukla , PhD, Margaret Proctor Mulligan Professor of medical pharmacology and physiology at the University of Missouri School of Medicine . “But many chronic drinkers are susceptible to liver damage when they binge drink. The liver is the metabolic powerhouse of the body and liver injury can compound damage to other organs. We studied the similarities and differences of gender-specific responses to repeat binge drinking. Our research showed just three binge drinking episodes triggered a response for more injury in the female rats.”

Shukla found a statistically significant difference using just four male and four female rats, giving them the same amount of alcohol three times at 12-hour intervals. He collected and analyzed blood and liver tissues four hours after the last binge episode. Shukla discovered the blood alcohol concentration was twice that in the female rats, but not all damage in males and females reflected that ratio. He discovered the female rats had nearly 4 times as much fatty build-up in the liver, a trigger for additional inflammation and damage.

“There’s a protein called diacylglycerol kinase-alpha (DGKa) that has been shown in other studies to promote tumor growth and cancer,” Shukla said. “In our findings, this protein goes up 20% in male rats, but increases 95% in females. However, any role this protein plays in alcohol-induced breast cancer is unknown and remains to be investigated in the future.”

Shukla says additional studies in humans will be needed to further understand the potential differences in how binge drinking affects males and females, and the metabolic causes for these differences. “Unfortunately, alcohol has been glamorized,” Shukla said. “It is dangerous. Don’t binge drink. The research is very clear.”

In addition to Shukla, the study authors include Ricardo Restrepo, PhD, Annayya Aroor, PhD, Robert Lim, PhD, Ronald Korthuis, PhD, and Xuanyou Liu, graduate student from the Department of Medical Pharmacology and Physiology at the University of Missouri School of Medicine; and David Ford, PhD, and Jacob Frank, graduate student, Department of Biochemistry and Molecular Biology and Center for Cardiovascular Research at Saint Louis University.

The study, “Binge alcohol is more injurious to liver in female than male rats: histopathological, pharmacological, and epigenetic profiles,” was recently published in the Journal of Pharmacology and Experimental Therapeutics. The authors of the study declare that they have no conflicts of interest.

Fighting Antibiotic Resistance

To combat the rise of drug-resistant bacteria, researchers are examining how one superbug adapts to fight an antibiotic of last resort, hoping to find clues that can prolong the drug’s effectiveness.

At Rice University and the University of Texas Health Science Center at Houston ran experiments to track the biochemical changes that vancomycin-resistant Enterococci (VRE) underwent as they adapted to fight another antibiotic, daptomycin. “We need to get to a stage where we can anticipate how these pathogens will become resistant to antibiotics so we can stay one step ahead of them,” said Rice biochemist Yousif Shamoo, co-author of a study in the journal Antimicrobial Agents and Chemotherapy that found VRE can develop resistance to daptomycin in more than one way. The stakes are high. In 2014, the World Health Organization reported that antibiotic-resistant infections were on pace to kill 10 million people per year worldwide by 2050.

According to the U.S. Centers for Disease Control, VRE is one of the nation’s leading antibiotic resistance threats. The CDC estimated VRE will infect some 20,000 people in the U.S. this year and kill 1,300 of them. Daptomycin, an antibiotic that first became available in 2003, is one of the last drugs doctors can use to fight multidrug-resistant superbugs like VRE, methicillin-resistant Staphylococcus aureus (MRSA) and glycopeptide resistant enterococci (GRE). Unfortunately, health officials documented cases of daptomycin resistance as early as 2005, and the number of cases is on the rise worldwide.

Shamoo said one of the principle findings of the study was that a specific strain of VRE, Enterococcus faecium, has an unusually diverse set of strategies for resisting antibiotics like daptomycin, and that diversity can make treatment of infections even more difficult. “By understanding how these pathogens acquire resistance, we can develop new treatment strategies or new ‘co-drugs’ that target their ability to become resistant,” Shamoo said. Co-drugs that target the evolution of resistance could be administered with antibiotics like daptomycin to both help patients fight off infection and stem the spread of increasingly resistant strains of bacteria in hospitals, he said.

Study lead author Amy Prater, a Ph.D. student who graduated from Rice in July, showed that the same strain of VRE could activate different biochemical pathways to activate up to three strategies, depending upon its environment. Shamoo said the multipronged strategy will make it more difficult for health officials to fight growing daptomycin resistance in VRE, but he said the results help clear up previously confusing experimental findings about VRE resistance, which is a step in the right direction. “If we understand how a pathogen acquires resistance, we can anticipate its next move, and hopefully act beforehand to cut it off,” Shamoo said. “Predictability is the key.”

Shamoo is Rice’s vice provost for research and a professor of biochemistry and cell biology in the Department of BioSciences. Additional co-authors include Heer Mehta and Abigael Kosgei of Rice and William Miller, Truc Tran and Cesar Arias of the UTHealth McGovern Medical School.