Research Roundup: experimental HIV vaccine shows promise in macaques; an ultrasound treatment for dementia and more!

Welcome to this week’s Research Roundup. These Friday posts aim to inform our readers about the many stories that relate to animal research each week. Do you have an animal research story we should include in next week’s Research Roundup? You can send it to us via our Facebook page or through the contact form on the website.

  • Experimental Vaccine Protects Rhesus Macaques from HIV-Like Infection. A study led by researchers from the Scripps Research Institute, the University of Pennsylvania and Harvard Medical School shows that rhesus macaques (Macaca mulatta) can be prompted to produce neutralizing antibodies against one strain of HIV that resembles the resilient viral form that most commonly infects people, called a Tier 2 virus. Published in the journal Immunity, the study also provides the first-ever estimate of vaccine-induced neutralizing antibody levels needed to protect against HIV.
Male rhesus macaque. Source: Kathy West.
  • Tiny implantable device for battling obesity. A tiny and battery-free implantable device has been developed by engineers at the University of Wisconsin-Madison to short-circuit hunger pangs. In laboratory testing, rats with the device shed approximately 40% of the body weight. The device generates and sends gentle electrical pulses to the vagus nerve in synchrony with stomach churns. By stimulating this nerve in synchrony with the stomach, the device fools the brain into thinking that the stomach is full. If or when the device reaches human trials, it will be a great alternative to procedures like a gastric bypass or sleeve. This is because these procedures are permanent, while the device can be removed and normal eating patterns can be resumed. Published in Nature Communications.
Image from Understanding Animal Research
  • Brain circuits of compulsive drug addiction identified. A study in mice identifies a brain adaptation that underlies the compulsive behavior associated with drug addiction, and which might explain why some drug users behave compulsively whereas others do not. Using optogenetics, researchers first trained mice to stimulate their own brain area associated with addiction, when pressing a lever. Next, mice received a mild electric shock, 33% of the time when they pressed the same lever. This allowed the researchers to discriminate between individuals who were perseveres (those which continued to press the lever) and renouncers (those which stopped pressing the lever). Communication between the orbitofrontal cortex (OFC), an area involved in decision-making, and the dorsal striatum increased in perseverers–optogenetic inhibition of this neural pathway turned persevering mice into renouncing mice. The authors also found that compulsive behavior could be suppressed or induced by respectively decreasing or increasing the strength of this neural connection. Published in Nature.