laughing gas and suicide risk
Researchers at Washington University School of Medicine are studying the effectiveness of nitrous oxide, commonly known as laughing gas, as a treatment for patients hospitalized for suicide risk. About 85 percent of people who attempt suicide are clinically depressed, and as many as one-third of patients with clinical depression don’t respond to existing drug and psychotherapy treatments. Most antidepressants affect norepinephrine and serotonin in the brain and can take weeks to improve a person’s symptoms. Nitrous oxide interacts with NMDA glutamate receptors and has more immediate effects. The gas also has very few side effects because it leaves the body quickly, but research has shown that its effects may impact the brain even after it’s out of the body. In a previous study, Drs. Charles Conway and Peter Negele tested 20 patients with treatment-resistant depression and found that two-thirds experienced improvement in their symptoms when treated with nitrous oxide. The new study is funded by a grant from the American Foundation.
cancer cell replication
We have new insight into how certain cancer cells operate and interact with chemotherapy. A research team led by Dr. Alessandro Vindigni of Saint Louis University studied BRCA-deficient cancer cells. BRCA proteins play a role in repairing and protecting damaged DNA during replication. When these proteins are missing, the DNA’s replication forks are susceptible to degradation from enzymes known as nucleases. “This explains why patients with BRCA mutations can be treated with chemo drugs that induce DNA damage and replication fork arrest,” Vindigni says. With this information, the research team investigated what nucleases degrade unprotected DNA and how they do so. It also determined that cells have a way to rescue degraded DNA and avoid cell death. This discovery offers insight into chemotherapy resistance and highlights new strategies for optimizing cancer treatments. The team’s paper on the subject is published in the journal Nature Communications.
preventing obesity
There may be a way to consume a high-fat diet and still prevent obesity, according to research from Washington University School of Medicine. A new study, published in the online journal eLife, has identified a way to prevent fat cells from growing larger, the main cause of weight gain. The research focuses on the Hedgehog protein pathway, which is active in many body tissues. When it was activated in fat cells in mice, the animals didn’t have substantial weight gain after eating a high-fat diet for eight weeks. Mice that didn’t have an active Hedgehog pathway became obese after consuming the same diet. Stimulation of Hedgehog and related proteins in fat cells kept the cells from collecting and storing fat droplets. Metabolic studies also found that mice with the active pathway had lower blood glucose levels and higher sensitivity to insulin. According to senior investigator Dr. Fanxin Long, it may be tricky to translate these findings to humans. Any drug or treatment that activates the Hedgehog pathway would need to be carefully targeted, but Long is hopeful the research will be effective in fighting obesity.
