Research briefs

Study links cancer risk to RNA functions

Australian cancer researchers have made an important new connection between a person’s cancer risk and the functions of circular RNAs, a recently discovered family of genetic fragments present in cells.

A Flinders University-led study published in Cancer Cell finds that specific circular RNAs can stick to the DNA in cells and cause DNA mutations that result in cancer.

‘While environmental and genetic factors have long been believed the major contributors to cancer, this revolutionary finding – which we call ‘”ER3D” (from ‘endogenous RNA directed DNA damage’) – ushers in an entirely new area of medical and molecular biology research,’ says Flinders University Professor Simon Conn

‘This opens the door to use these molecules as new therapeutic targets and markers of disease at a very early stage, when the likelihood of curing cancers is much higher.’

The research compared the neonatal blood tests or Guthrie cards of babies who went on to develop acute leukemia as infants with children without any blood disorders. This found that one specific circular RNA was present at much higher levels at birth, prior to onset of the symptoms of leukemia.

The findings suggest it is the abundance of the circular RNA molecules within certain individuals’ cells which is a major determinant for why they develop these specific cancer-causing genes or oncogenes and other do not.

Fatty fish consumption increases cell membrane fluidity

Eating fatty fish decreases the lipophilic index in people with impaired glucose metabolism or coronary heart disease, according to a new study from the University of Eastern Finland. The lipophilic index is considered a marker of cell membrane fluidity, and a low lipophilic index indicates better membrane fluidity and cardiovascular benefit.

The researchers used data from two randomised clinical trials to study the effects of fish and camelina sativa oil intake on the lipophilic index. The first study included 79 men and women with impaired glucose tolerance. The second study included 33 men and women with cardiovascular disease.

Study participants were randomly divided into four groups for a 12-week intervention: the camelina oil group, the fatty fish group, the lean fish group, and the control group in the first study. In the second study, subjects were randomly divided into the fatty fish, lean fish, and control groups for an eight-week intervention. The lipophilic index was calculated based on erythrocyte membrane fatty acids in the first study, and serum phospholipid fatty acids in the second study.

In both studies, eating four meals of fatty fish per week reduced the lipophilic index, which indicates better membrane fluidity. Better membrane fluidity has been associated with lower cardiovascular risk.

Finding rewrites understanding Parkinson’s disease

Researchers have solved a longstanding mystery about how a protein helps rid the body of damaged mitochondria in findings that could help lead to potential new treatments for Parkinson’s disease.

This answers a long-standing question about how Optineurin, a protein that is highly expressed in the human brain, helps the body remove damaged mitochondria.

The new research, published in Molecular Cell, solves a mystery about how the protein Optineurin recognises unhealthy mitochondria ‘tagged’ by PINK1 and Parkin proteins, enabling delivery to our body’s garbage disposal system.

The researchers found that Optineurin links damaged cellular materials to the garbage disposal machinery in a highly unconventional way unlike similar proteins.

PINK1 acts as a ‘watch-house’ inside the mitochondria, responsible for monitoring their health. When it detects problems, it activates Parkin, which tags damaged mitochondria for removal.

The new study revealed that Optineurin removes damaged mitochondria by binding to an enzyme known as TBK1. From there, they found that TBK1 goes on to activate a specific cellular machine that is key to generating these garbage bags around unhealthy mitochondria.

This finding may provide a framework to target PINK1 and Parkin mitophagy in disease and prevent the build-up of damaged mitochondria in neurons.

Fewer fractures for preterm and low birthweight newborns

Pre-term and low birthweight infants have fewer fractures in childhood than full-term and normal-weight newborns, according to a new a study based on one million children and nearly 100,000 fractures.

This contrasts with earlier smaller studies that reported an increased risk of fractures in childhood in children born pre-term and an earlier study from Finland which found that pre-term infants continue to have lower bone mineral density even in adulthood.

The study from the University of Eastern Finland and Kuopio University Hospital found that pre-term and low birthweight infants had significantly fewer fractures in childhood than other newborns. The difference was particularly evident in children born before the 32nd week of pregnancy, who had 23% fewer fractures than in children born full-term.

There were also fewer fractures in the group whose birthweight was less than 2,500 grams, and especially in the group whose birthweight was less than 1,000 grams.

‘It can be concluded that the risk of fractures in childhood is explained by factors other than the effect of being pre-term on bones. However, we know that pre-term children are less likely to participate in sports, and they have less risk-taking behaviour even as adults than full-term children,’ the researchers said.

They note further research is needed on whether foetal growth disorder, i.e., abnormal growth in relation to weeks of pregnancy, is associated with fractures in early childhood, as this was not addressed in the present study.

Scientists identify common cause of gastro

Atype of bacteria not routinely tested for has been discovered as the second most common cause of bacterial gastroenteritis.

In a study of over 300,000 patient samples, UNSW Sydney scientists have discovered that a type of bacteria known as Aeromonas are the second most prevalent bacterial pathogens found in patients with gastroenteritis.

It was previously believed that Salmonella was the most common cause of bacterial gastro after Campylobacter

‘Our results have found that Aeromonas are the second most prevalent enteric bacterial pathogens across all age groups, and in fact are the most common enteric bacterial pathogens in children under 18 months,’ the researchers say.

The team used quantitative real-time PCR testing of faecal samples and analysed data from 341,330 patients with gastroenteritis in Australia between 2015 and 2019.

The most frequent occurrences of Aeromonas enteric infections was in young children and individuals over 50 years old, suggesting a higher susceptibility to these infections during stages when the immune system tends to be weaker.

There was also an increase in Aeromonas enteric infections among patients aged 20-29 years, which could be attributed to increased exposure to the pathogen at this age.

These findings suggest that both human host and microbial factors contribute to the development of Aeromonas enteric infections. The high rate of Aeromonas infection discovered suggest that Aeromonas species should be included on the common enteric bacterial pathogen examination list.

AI platform targets safe use of medicines after discharge

Amajor new $2.9 million digital health project led by Flinders University will target the dosage and failures of prescription drugs used by patients at home after they leave hospital.

The ‘AutoMedic’ project aims to create a more streamlined and accurate electronic record of prescription medicine used by patients discharged from six South Australian public hospitals to better manage their recovery and longer-term health outcomes.

The trial will provide a useful model for a smart, scalable solution to detect and resolve medicine harm’, says Associate Professor of Digital Health Niranjan Bidargaddi, from Flinders’ College of Medicine and Public Health.

More accurate e-health solutions are expected to create an AI-enhanced medicine review for individual patients, supporting hospital clinical pharmacists to give advice or alternative prescriptions in a timely manner before discharge.

This new e-health system will help identify patients most at risk of adverse events due to medicine errors when in hospital and enable GPs and pharmacies to intervene and assist with such problems, which can lead to hospital readmissions.

The new system will work in tandem with the federal My Health Record platform, which collates prescription, imaging and pathology data from Medicare-funded programs, a new single electronic medical record (‘Sunrise AllScripts’) operating at public hospitals in SA.