Research news in brief

Gas sensing gut pill beats breath test diagnosis

New trials of an ingestible sensor have revealed that the device is 3000 times more accurate than the technology currently used to diagnose many gut disorders. The gas-sensing capsule developed by researchers at RMIT University could surpass breath testing as the benchmark for diagnosing gut disorders, paving the way to discovering previously undiagnosed conditions. The vitamin pill-sized capsule, currently being commercialised by Atmo Biosciences, provides real-time detection and measurement of hydrogen, carbon dioxide and oxygen in the gut. These data can be sent to a mobile phone. Capsule co-inventor, RMIT’s Dr Kyle Berean, said that the second human trials have revealed information about gas production in the gut previously masked when measured indirectly through the breath. The results are published in Alimentary Pharmacology and Therapeutics. Intestinal gases are currently used to diagnose disorders including small intestinal bacterial overgrowth and carbohydrate malabsorption. Of the one in five people worldwide who will have a gastrointestinal disorder in their lifetime, almost a third remain undiagnosed due to a lack of reliable tests available to gastroenterologists. Findings from the first human trials revealed the stomach releases oxidising chemicals to break down and beat foreign compounds that are staying in the stomach for longer than usual. Such an immune mechanism has never been reported before. This second article made a direct comparison between measuring hydrogen production within the gut via the gas-sensing capsule and indirect measurement through breath testing. Trials were conducted on nine healthy individuals in a blinded comparative study on absorbable versus fermentable carbohydrates.

New drugs put cancers to sleep permanently

In a world first, researchers from the Walter and Eliza Hall Institute of Medical Research have discovered a new type of anticancer drug that can put cancer cells into a permanent sleep, without the harmful side effects caused by conventional cancer therapies. Published in Nature, the research reveals the first class of anticancer drugs that work by arresting tumour growth and spread without damaging the cells’ DNA. The new class of drugs could provide an exciting alternative for people with cancer and has already shown great promise in halting cancer progression in models of blood and liver cancers, as well as in delaying cancer relapse. The new class of drugs was the first to target KAT6A and KAT6B proteins. Both are known to play an important role in driving cancer. KAT6A sits at number 12 on the list of genes most commonly amplified in cancers. “Early on, we discovered that genetically depleting KAT6A quadrupled the life expectancy in animal models of blood cancers called lymphoma. Armed with the knowledge that KAT6A is an important driver of cancer, we began to look for ways of inhibiting the protein to treat cancer,” said Associate Professor Tim Thomas. “Rather than causing potentially dangerous DNA damage, as chemotherapy and radiotherapy do, this new class of anticancer drugs stops cancer cells dividing by switching off their ability to ‘trigger’ the start of the cell cycle. The technical term is cell senescence. The cells are not dead, but they can no longer divide and proliferate. Without this ability, the cancer cells are effectively stopped in their tracks.”

Both long term abstinence and heavy drinking may increase dementia risk

People who abstain from alcohol or consume more than 14 units a week during middle age (midlife) are at increased risk of developing dementia, finds a study in The BMJ. However, the underlying mechanisms are likely to be different in the two groups. Previous studies indicate that moderate drinking is associated with a reduced risk of dementia, whereas both abstinence and heavy drinking are associated with a risk of dementia. But the evidence is far from conclusive, and the reasons underlying these associations remain unclear. A team of researchers from the French National Institute of Health and Medical Research and from University College London in the UK set out to investigate the association between midlife alcohol consumption and risk of dementia into early old age. They also examined whether cardiometabolic disease (including stroke, coronary heart disease, and diabetes) has any effect on this association. Their findings are based on 9087 British civil servants aged between 35 and 55 years in 1985 who were taking part in the Whitehall II Study, which is looking at the impact of social, behavioural and biological factors on long term health. Participants were assessed at regular intervals between 1985 and 1993 (average age, 50 years) on their alcohol consumption and alcohol dependence. Alcohol consumption trajectories between 1985 and 2004 were also used to examine the association of long term alcohol consumption and risk of dementia from midlife to early old age. Admissions for alcohol-related chronic diseases and cases of dementia from 1991, and the role of cardiometabolic disease were then identified from hospital records. Of the 9087 participants, 397 cases of dementia were recorded over an average follow-up period of 23 years. Average age at dementia diagnosis was 76 years. After taking account of sociodemographic, lifestyle and health-related factors that could have affected the results, the researchers found that abstinence in midlife or drinking more than 14 units a week was associated with a higher risk of dementia compared with drinking 1–14 units of alcohol a week. Among those drinking above 14 units of alcohol a week, every 7 unit a week increase in consumption was associated with 17% increase in dementia risk. History of hospital admission for alcohol-related chronic diseases was associated with a four times higher risk of dementia. In abstainers, the researchers show that some of the excess dementia risk was due to a greater risk of cardiometabolic disease. Alcohol consumption trajectories showed similar results, with long term abstainers, those reporting decreased consumption, and long term consumption of more than 14 units a week, all at a higher risk of dementia compared with long term consumption of 1–14 units a week.

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