Pre-dementia phases including subjective cognitive impairment (SCI) and mild cognitive impairment (MCI) develop over decades and can be reversed, or halted, or deteriorate into Alzheimer’s disease (AD). The pathology of AD is said to be linked with oxidative damage and inflammation.
According to a recent article published in the BMC Nutrition journal (DOI: https://doi.org/10.1186/s40795-021-00482-8), consuming a juice of bilberries and red grapes decreased levels of biomarkers for inflammation and tissue damage in aged men. In the 9-week double-blind, placebo-controlled study, researchers tested the effects of consuming polyphenol-rich juice made of European wild blueberries (Vaccinium Myrtillus) and red grapes (Vitis Vinifera) on cognitive benefits as well as the biomarkers for oxidative stress, inflammation, and tissue damage.
The sixty-one Norwegian research participants were all men, aged 67-77 years, and had subjective memory impairment. The intervention group consumed 660 ml of bilberry/red grape juice per day while the control consumed the same quantity of placebo juice.
No significant differences were observed between the placebo and intervention groups on visual memory or psychomotor tempo; however, the intervention group experienced significantly decreased levels of tissue damage and inflammatory biomarkers compared to the control. LDH, the tissue damage biomarker, is present in several tissues, including the heart, lungs, kidneys, and liver; therefore, elevated levels might signal organ damage. The research found LHD was significantly reduced in the intervention group compared to the control. Additionally, the within-group LHD levels for the intervention group reduced from 362 U/L to 346 U/L.
Further analysis suggests that there is an association between higher inflammatory levels and impaired memory skills. Compared to the control, there were also greater decreases in the intervention group for myocardium specific CK as well as plasma creatine kinase. Additionally, the significant increases of several polyphenols in fasting plasma following bilberry/red grape juice consumption and the seeming effect to dampen inflammation suggests that the polyphenols are bioavailable and bioactive.
The researchers conclude that “the intervention decreased levels of tissue damage- and inflammation biomarkers which indicate beneficial effects of the intervention possibly by restraining chronic inflammation, oxidative stress and the subsequent oxidative damage.”