Key Points:
- Supplementing aged rats with resveratrol protects against age-related memory decline and motor dysfunction.
- Treatment with resveratrol mitigates brain inflammation (neuroinflammation) by regulating the activity of sirtuin 1 (SIRT1) – a critical protein for genomic stability and DNA repair.
Scientists have hailed resveratrol as one of the most promising anti-aging interventions to date, with studies revealing that supplementation extends the lifespan of multiple model organisms. What’s more, this natural polyphenol, commonly found in wine and certain plants, nuts, and berries, is widely touted for its potent anti-oxidative and anti-inflammatory properties, which contribute to neuroprotection in models of Alzheimer’s and Parkinson’s. Although resveratrol’s effects on neurodegenerative diseases are more established, few studies have investigated the effects of resveratrol supplementation during normal aging.
In a new study published in the Journal of Functional Foods, researchers from the University of the Balearic Islands in Spain explored the neuroprotective effects of chronic resveratrol supplementation in disease-free aged rats. Sarubbo and colleagues reported that treating aged rats with resveratrol preserved memory function and mitigated motor dysfunction. Furthermore, the findings suggest that resveratrol’s neuroprotective effects stem from alleviating brain inflammation via SIRT1 regulation.
Resveratrol Boosts Memory and Enhances Motor Function
The brain is constantly orchestrating harmonious neuron networks with finesse, allowing us to execute vital functions and catalog memories. However, aging slowly intervenes and eventually deregulates the brain’s responses to stimuli, ultimately limiting the way we think and move. Scientists are finding more and more evidence that resveratrol and other polyphenols like fisetin and quercetin can potentially mitigate disease-induced memory, motor, and muscle decline. With this in mind, Sarubbo and colleagues examined whether resveratrol exerts protective effects on memory and motor function in naturally aging rats.
To evaluate memory, the investigators employed the novel object recognition test, an exam to assess the rats’ ability to remember and recognize previously unseen objects. Rats that spend more time exploring a novel object over a familiar one imply superior memory. Upon experimentation following resveratrol treatment for 28 days, treated rats spent significantly more time exploring the novel object than their untreated counterparts, demonstrating preserved memory.
The investigators then subjected rats to a common motor experiment (rotor rod test) that tests the rats’ ability to balance on a rotating rod. By the end of supplementation, those that received resveratrol treatment lasted 58% longer on the rotating rod (before falling off) than untreated rats, indicating that treatment enhanced motor function upon aging. Collectively, these initial findings show that resveratrol improves key functions tied to brain health.
Resveratrol Decreases Brain Inflammation
Scientists coined the term “inflammaging” to detail the intimate relationship between chronic inflammation and the development of several age-related diseases, especially those tied to neurodegeneration. One vital protein at the epicenter of inflammation regulation in the brain is SIRT1, the activity of which naturally declines with age. Notably, research has shown that decreased SIRT1 activity leads to the modification (acetylation) of another protein called NF-kB, which, upon acetylation, drives inflammation.
To determine if resveratrol treatment could ameliorate brain inflammation, the research team looked at the rats’ levels of SIRT1 and the acetylated form of NF-kB in the hippocampus – the brain region responsible for learning and memory. Compared to young untreated rats, old untreated rats exhibited significantly lower levels of SIRT1, highlighting that SIRT1 activity decreases with age. However, resveratrol treatment restored SIRT1 levels by 41%.
The results also showed that the levels of acetylated NF-kB were higher in old untreated rats than in young untreated rats, reasserting the connection between decreased SIRT1 activity and increased NF-kB activity. Moreover, rats that took resveratrol displayed NF-kB levels similar to those in young untreated rats. Taken together, the findings suggest that resveratrol attenuates brain inflammation through SIRT1 and NF-kB regulation.
Taking Resveratrol To Counter Aging
Overall, the data presented in this study show that chronic resveratrol supplementation counters age-related memory and motor dysfunction by quenching brain inflammation through SIRT1 and NF-kB regulation. Growing evidence across multiple model organisms reaffirms resveratrol’s potential to delay and thwart various features of aging. Uniquely, some female rodent studies have found that resveratrol protects against age-related infertility, which drastically increases in women above the age of 35. Furthermore, resveratrol supplementation has been shown to boost mitochondrial function and reduce cellular senescence – a hallmark of many age-related diseases.
Humans can only intake relatively small quantities of resveratrol if consumed naturally. Thus, taking resveratrol in supplement form is ideal to potentially experience its health-boosting effects. That being said, further research is needed before we can claim resveratrol as the future of anti-aging therapeutics.