Current HIV drug therapies are not able to control the virus’ complete replication in the brain and are therefore ineffective against complications linked to neurocognitive impairment in HIV patients. However, a new study published online in the Journal of NeuroVirology has revealed that a group of plant polyphenols known as catechins that occur naturally in green tea and the seed of the cacao tree may help to prevent these neurological complications.

Earlier studies have shown that the protein brain-derived neurotrophic factor (BDNF) plays a vital role in supporting the survival and growth of neurons within the brain and that it is active in brain areas linked to learning, higher thinking and memory. It has been discovered that HIV patients have lower levels of BDNF in their brains than healthy individuals, which indicates that this could be directly responsible for the cognitive impairment suffered.

Joseph Steiner and his team from the Johns Hopkins University decided to assess the impact of 2000 compounds on brain cells in the laboratory. The compounds contained both natural substances and FDA-approved drugs, and the team discovered various compounds that could potentially help in protecting the brain’s neurons, amongst which are 9 compounds that are related to epicatechin, a compound found in cocoa and green tea leaves.

After further evaluation and comparison with the antioxidant found in red wine, i.e. resveratrol, the team discovered that epicatechin and epigallocatechin gallate (EGCG) were the most effective in assisting to protect neurons by inducing BDNF production.

Even though there is sufficient evidence of epicatechin’s and EGCG’s activities, the potential discovery of being responsible for inducing BDNF production represents a welcome advancement in this field. Its therapeutic potential is further increased by the fact that these compounds readily cross the blood-brain barrier, which has often been a major hurdle in developing therapies that are targeted at the brain. This offers new hope for HIV patients since there is no neuroprotective therapy available for these patients who have a cognitive impairment related to HIV.

The researchers conclude:

“Due to its simpler structure and more efficient blood-brain barrier penetration properties, epicatechin might be the best therapeutic candidate for neurodegenerative diseases. These include HIV-associated cognitive disorders where oxidative stress is an important pathophysiological mechanism.”

The team adds that further research in HIV patients is necessary to establish the real efficacy of these natural compounds.