Researchers from the Georgetown University Medical Center has discovered a certain molecule commonly found in red wines and chocolates to be effective in reducing neuronal inflammation, slowing down cognitive decline in Alzheimer's patients.

The new study of the naturally occurring compound resveratrol, which was presented at the Alzheimer's Association International Conference 2016 in Toronto last July 27, revealed that the molecule has the ability to restore the integrity of the blood-brain barrier, preventing harmful immune molecules secreted by immune cells in the body from infiltrating into brain tissues.

"These findings suggest that resveratrol imposes a kind of crowd control at the border of the brain. The agent seems to shut out unwanted immune molecules that can exacerbate brain inflammation and kill neurons," explained neurologist Charbel Moussa, MD, PhD, scientific and clinical research director of the GUMC Translational Neurotherapeutics Program, in a statement.

For the study, the researchers examined specific molecules in the cerebrospinal fluid taken from 38 participants with biomarker-confirmed Alzheimer's disease. The participants were divided into two groups. The first group were treated with resveratrol for a year, which is equivalent to 1,000 bottles of red wine. On the other hand, the second group served as the control group and were given placebo.

The researchers noted that the group treated with resveratrol experienced a 50 percent reduction of matrix metalloproteinase-9 (MMP-9) levels in the cerebrospinal fluid. High MMP-9 levels can breakdown the blood-brain barrier, which in turn allows protein and molecules from the body to enter the brain.

Furthermore, the researchers discovered that patients treated with resveratrol have an increased levels of molecules that are associated with a long-term beneficial or "adaptive" immune reaction. This suggests the involvement of inflammatory cells that are resident in the brain in the removal and degradation of neurotoxic proteins.

Moussa noted that the efficacy of resveratrol should be further tested in the Phase III trial. However, researchers believe that it is unlikely that resveratrol by itself can treat Alzheimer's because it does not inhibit the destruction of brain neurons by tau. Therefore, a more beneficial treatment for Alzheimer's would be a combination of resveratrol and other agents that targets tau.