Australian researchers have discovered a previously overlooked group of bladder nerves that help detect urinary tract infections (UTIs) and trigger the body’s response to clear them, providing a potential new target for future bladder pain therapies.

The study shows that bladder nerves located close to the lining of the bladder act as a frontline infection sensor, helping the body recognise UTIs and trigger responses that reduce the severity and spread of infection.

UTIs are among the most common bacterial infections worldwide, with more than 400 million cases reported every year. Nearly one in three women will experience UTIs before the age of 24, and many elderly people and those with bladder issues from spinal cord injuries can experience multiple UTIs in a single year.

Symptoms often include frequent urination, a sudden urge to urinate, pain during urination, and pelvic discomfort can be debilitating for some patients.

Flinders University’s Dr Luke Grundy says that while scientists have long understood how the bladder senses as it fills and triggers urination, the role of a specialised group of bladder nerves near the bladder lining has remained unclear.

“Most bladder nerves act like a fuel gauge, telling the brain when the bladder is filling up and needs emptying,” says Dr Grundy, Head of the NeuroUrology Research Group at Flinders University.

“The nerves we studied in this research are different. They sit close to the bladder lining and appear to act more like an early warning system, detecting infection and inflammation.

“They don’t just sense infection. They help coordinate the body’s response to it by triggering pain and urinary frequency, behaviours that appear to help clear bacteria from the bladder as part of the body’s defence system.”

Lead author and recently graduated PhD student Dr Cindy Tay says the discovery changes how these nerves are understood.

“These mucosal nerves have puzzled scientists for almost two decades because they stay quiet while the bladder fills and empties, which is the main job of the bladder,” says Dr Tay.

“What we’ve found is that they have a hidden job — acting as an early warning system that springs into action the moment infection takes hold.”

The research team developed a novel method to selectively study a specialised group of sensory nerves in the bladder lining of mice, revealing that while these nerves play little role in normal bladder function, they become highly responsive during a UTI and help detect and respond to infection.

“When the bladder is healthy, these nerves are relatively quiet, but during a urinary tract infection they become highly sensitive and respond to the presence of bacteria and inflammation,” says Dr Grundy.

“It may feel unpleasant, but urinating more frequently actually helps clear the infection by flushing out the harmful bacteria.”

The study also helps explain why people with conditions affecting nerve function may be more prone to recurrent or severe UTIs.

“If the nerves that detect infection aren’t working properly, the body may not respond as effectively,” says Dr Grundy.

Building on previous research, the new study reveals a deeper understanding of how UTIs affect bladder function and the nervous system, and could help develop new treatments that target these nerves to relieve UTI-related symptoms.

“Our findings provide new insight into how the bladder detects and responds to infection, helping explain the biological processes that drive the pain, urgency and discomfort commonly experienced during UTIs,” says Dr Grundy

Researchers say the next challenge is to develop therapies that ease the pain and urgency associated with UTIs while preserving the protective role these nerves play in fighting infection.

The paper, ‘Bladder mucosal afferents detect UTI and aid pathogen clearance,’ by Cindy Tay, Harman Sharma, Stewart Ramsay (University of Adelaide), Georgia Bourlotos, Sarah K Manning, Natalie E Stevens, Sophie J Miller, Geraint B Rogers, David J Lynn, Feargal J Ryan, Andrea M Harrington (University of Adelaide), Vladimir Zagorodnyuk, Steven L Taylor and Luke Grundy was published in Proceedings of the National Academy of Sciences (PNAS).

McGill University researchers have developed a new tool to identify heart disease risk in women earlier in life.

Findings from a study published in JACC: Advances highlight gaps in existing approaches.

“Heart disease is the leading cause of death in women, yet existing risk tools were developed in older populations and ignore factors unique to women,” said senior author Robert Platt, Professor in the Department of Epidemiology, Biostatistics, and Occupational Health and Director of the School of Population and Global Health.

While pregnancy complications are known to be linked to future heart risk, there has been no way to identify which younger women are most at risk, he added.

Detecting risk earlier

Using health data from more than 260,000 women in the UK aged 15 to 45 who had given birth, researchers developed and validated a prediction model to estimate future heart disease risk. Participants were followed for nearly four years after delivery.

The model identified several factors – not included in existing tools – that can help predict risk, including hypertensive disorders of pregnancy, gestational diabetes, preterm birth, PCOS, depression, thyroid disorders, oral contraceptive use and social deprivation.

The findings suggest some women, particularly younger women often considered low risk, may face a higher risk of heart disease earlier than previously recognized.

“Millions of women who give birth each year are never considered candidates for cardiovascular risk assessment simply because of their age,” said co-author Kristian Filion, Professor in the Departments of Medicine and of Epidemiology, Biostatistics, and Occupational Health.

If integrated into routine postpartum care, this tool could enable earlier monitoring, lifestyle counselling or referral to a specialist, potentially helping prevent a heart attack or stroke later in life, he added.

The next step is to validate the model in Canada and the United States. In the longer term, the goal is to integrate a practical calculator into electronic health records so higher-risk patients can be identified earlier.

About the study

“Development and Validation of a Prediction Model for Cardiovascular Risk in Reproductive-Aged Women” by Sonia Grandi, Kristian Filion, Jennifer Hutcheon, Graeme Smith, and Robert Platt was published in JACC: Advances. The study was supported by the Canadian Institutes of Health Research.

A person’s posture appears to affect their emotions and decision-making ability more than they realize, according to new research from McGill University. In a recent study, participants sitting upright performed better at a risk-taking task and reported more positive feelings than did their peers in the slouching or control groups.

Though the effects were modest and observed in a laboratory setting, the results highlight the body’s influence on our mood and behavior, said Jorge Armony, professor in the Departments of Psychiatry and Psychology at McGill and senior author of the study.

A cover story to influence body position

Armony and graduate student Soren Wainio-Theberge, who originated the idea for the research and is a co-author of the paper, recruited nearly 200 participants from the McGill community.

After some initial testing on a computer monitor, they asked them to complete a new task on a tablet, under the guise of testing a mobile application. For some, the tablet was positioned on a stand on an adjustable table, to encourage an upright posture while sitting. For others, it was placed flat on the desk, which was also positioned at a lower setting, prompting participants to hunch over.

Participants then completed a risk-taking test, in which players can earn rewards by inflating a virtual balloon, but risk losing everything if it bursts. Over the course of the task, participants in the upright posture took greater risks and tended to earn greater rewards.

“This suggests they were not acting more impulsively but rather were engaging in more effective risk-taking,” explained Armony.

In the accompanying questionnaire, participants in the upright group also reported significantly higher feelings of pride, which is associated with a positive mood.

Bringing new insight to posture research

The findings shed light on the long-debated notion that the body’s posture can influence the mind.

The McGill team tested this relationship while avoiding concerns associated with previous studies.

The researchers avoided telling subjects which posture to adopt, but, rather, influenced their choice without their knowledge. This helped address a common criticism of earlier “power pose” research: that results may simply reflect that participants responded to researchers’ expectations. In post-experiment interviews, most participants indicated that they were unaware their posture had been manipulated.

The researchers also used video software to measure neck angle as a benchmark for posture conformity. In previous studies, this had not often been measured.

The findings do not mean that changing posture can dramatically transform a person’s life, Armony cautioned, but it does raise interesting questions about whether everyday features of our environment – such as workplace ergonomics – can subtly influence mood and behavior.

About the study

“Manipulating posture implicitly through environmental constraints influences mood and
risk-taking behaviour”, by Soren Wainio-Theberge and Jorge Armony, was published in the British Journal of Psychology.