According to the World Health Organization, around 55 million people worldwide suffer from dementia. Although there’s currently no cure, researchers are unabatedly looking for treatments that could improve the lives of dementia patients and their care-givers. Working towards that end, researchers in Japan have recently developed a nasal spray that may lead to a safe and effective way to prevent dementia.
Coming from Osaka Metropolitan University, the scientists have reported successful preclinical tests of a novel nasal spray intended to prevent the onset of neurodegenerative diseases such as Alzheimer’s. The spray consists of a combination of two pre-existing drugs, and the study’s findings show that it improved cognitive function in several different mice models of dementia.
The study, published in the journal Frontiers in Neuroscience, follows up on foundational research from 2016 that discovered a common antibiotic called rifampicin can reduce the accumulation of toxic proteins in the brain associated with the development of Alzheimer’s. That research proved that the drug could improve cognitive function if administered during the earliest stages of the disease. Although, it also found that long-term administration has side effects such as liver damage.
Confronted with that problem, in 2018 the researchers explored whether administering rifampicin through a nasal spray would allow the drug to reach the brain more directly, avoiding the damaging effects on the liver. It turned out that was indeed the case, as the researchers observed improved cognitive function and reduced levels of liver toxicity.
“To further secure the safety of nasal rifampicin, we hypothesized that rifampicin’s undesired actions could be antagonized by other compounds,” the researchers wrote in the current study. “Thus, we explored the literature for a compound that possesses hepatoprotective actions opposite to rifampicin and, if possible, additional clinical effects that rifampicin does not show.”
As a result, the new study brought a natural antioxidant called resveratrol into the mix. The team hypothesized that combining resveratrol with rifampicin into a nasal spray solution could pave the way for a safe long-term treatment that could prevent or at least slow down the development of dementia.
Promising test results
To study this hypothesis, over the course of a month, the scientists administered a fixed-dose combination of the drug intranasally five times a week to several different mouse models of neurodegeneration, including Alzheimer’s disease. The findings showed the new combination of resveratrol and rifampicin significantly improved the cognitive function of the mice and inhibited the accumulation of toxic proteins in the brain.
The scientists also observed that the drug combination didn’t damage the liver and was more effective at preventing neurodegeneration compared to delivering each drug individually. Following the successful results, the team is now preparing to move the study to human trials.
Source study: Frontiers in Neuroscience — Oligomer-Targeting Prevention of Neurodegenerative Dementia by Intranasal Rifampicin and Resveratrol Combination