Effect of chlorogenic acids on fatigue and sleep in healthy males: A randomized, double-blind, placebo-controlled, crossover study

Dietary polyphenols and sleep modulation: Current evidence and perspectives

Polyphenols are plant compounds with several biological activities. This review aims to summarize current knowledge on the potential role of polyphenols in modulating sleep. A total of 28 preclinical studies, 12 intervention studies and four observational studies exploring the role of polyphenol intake on sleep were identified. From animal studies, 26 out of the 28 studies found beneficial effects of polyphenols on sleep architecture. Three out of four human observational studies found a beneficial association between polyphenol intake and sleep parameters. And, among clinical intervention studies, eight from a total of 12 studies found some beneficial effect of polyphenol intake on various sleep parameters, although some discrepancies between studies were found. Overall, emerging evidence suggests a benefit of polyphenol intake on sleep. Several mechanisms of action have been suggested, ranging from effects on neurotransmitters to an action through the gut-brain axis. However, more research in this field is needed, emphasizing the use of nutritional doses in mechanistic studies and interventions targeting participants with sleep problems. This would allow to elucidate whether an additional biological effect of polyphenols is modulation of sleep, a behavior associated with adverse health outcomes.

Effects of Dendropanax morbiferus Leaf Extract on Sleep Parameters in Invertebrate and Vertebrate Models

Dendropanax morbiferus is highly valued in traditional medicine and has been used to alleviate the symptoms of numerous diseases owing to its excellent antioxidant activity. This study aimed to evaluate the sleep promotion and related signaling pathways of D. morbiferus extract (DE) via behavioral analysis, molecular biological techniques, and electrophysiological measurements in invertebrate and vertebrate models. In Drosophila, the group treated with 4% DE experienced decreased subjective nighttime movement and sleep bout and increased total sleeping time. Moreover, substantial changes in locomotor activity, including distance moved, velocity, and movement, were confirmed in the 4% DE-treated group. Compared to Drosophila in which insomnia and oxidative stress were induced by exposure to 0.1% caffeine, the DE-treated group improved sleep-related parameters to the level of the normal group. In the Drosophila model, exposure to 4% DE upregulated the expression of gamma-aminobutyric acid (GABA)-related receptors and serotonin receptor (5-HT1A), along with the expression of antioxidant-related factors, glutathione, and catalase. In the pentobarbital-induced sleep test using ICR mice, the duration of sleep was markedly increased by high concentration of DE. In addition, through the electroencephalography analysis of SD-rats, a significant increase in non-rapid-eye-movement sleep and delta waves was confirmed with high concentrations of DE administration. The increase in sleep time and improvement in sleep quality were confirmed to be related to the expression of altered GABA receptors and the enhancement of the contents of the neurotransmitters GABA and serotonin (5-HT) because of high DE administration. High-dose administration of DE also increased the expression of antioxidant-related factors in the brain and significantly decreased malondialdehyde content. Taken together, DE induced improvements in sleep quantity and quality by regulating neurotransmitter content and related receptor expression, along with high antioxidant activity, and may have a therapeutic effect on sleep disorders.

Potential of Polyphenols for Improving Sleep: A Preliminary Results from Review of Human Clinical Trials and Mechanistic Insights

Global epidemiologic evidence supports an interrelationship between sleep disorders and fruits and vegetable ingestion. Polyphenols, a broad group of plant substances, are associated with several biologic processes, including oxidative stress and signaling pathways that regulate the expression of genes promoting an anti-inflammatory environment. Understanding whether and how polyphenol intake is related to sleep may provide avenues to improve sleep and contribute to delaying or preventing the development of chronic disease. This review aims to assess the public health implications of the association between polyphenol intake and sleep and to inform future research. The effects of polyphenol intake, including chlorogenic acid, resveratrol, rosmarinic acid, and catechins, on sleep quality and quantity are discussed to identify polyphenol molecules that may improve sleep. Although some animal studies have investigated the mechanisms underlying the effects of polyphenols on sleep, the paucity of trials, especially randomized controlled trials, does not allow for conducting a meta-analysis to reach clear conclusions about the relationships among these studies to support the sleep-improving effects of polyphenols.

Short-Term Intake of Chlorogenic Acids Improves Psychomotor Speed and Motor Speed in Adults: A Randomized Crossover Trial

Chlorogenic acid (CGA), a polyphenolic compound found in various plants, has been reported to improve cognitive function. However, it remains unclear how long it takes for CGAs to exert their effects. Here, we evaluated the short-term effects of CGAs on cognitive function. We assessed the effects of 2-week CGA intake on cognitive function. The study was carried out as a randomized, double-blind, placebo-controlled, crossover trial. Twenty-six healthy Japanese participants (50–65 years of age) were randomly assigned to either the active beverage (CGAs: 270 mg) or the placebo beverage group daily for 2 weeks. After a 2-week washout period, the participants consumed the other beverages. We assessed cognitive function at baseline and following the first treatment period using the Japanese version of CNS Vital Signs. CGAs significantly improved the scores for psychomotor speed, motor speed, and right and left finger tapping compared to placebo. In addition, processing speed scores improved significantly from baseline only after CGA intake. In conclusion, CGAs were confirmed to improve cognitive function over a short period of two weeks.

Association between Coffee Consumption/Physical Exercise and Gastric, Hepatic, Colon, Breast, Uterine Cervix, Lung, Thyroid, Prostate, and Bladder Cancer

Although the effects of coffee consumption and physical exercise on the risk of cancer have been suggested, their interactions have not been investigated. The present cross-sectional study aimed to investigate the correlation of coffee consumption and physical exercise with cancer. Participants ≥40 years old in the Korean Genome and Epidemiology Study 2004–2016 were included (n = 162,220). Histories of gastric cancer, hepatic cancer, colon cancer, breast cancer, uterine cervix cancer, lung cancer, thyroid cancer, prostate cancer, and bladder cancer were analyzed according to the coffee consumption groups using logistic regression models. The odds among individuals in the >60 cups/month coffee group were lower for gastric cancer (adjusted odds ratio (aOR) = 0.80 (95% confidence intervals = 0.65–0.98)), hepatic cancer (0.32 (0.18–0.58)), colon cancer (0.53 (0.39–0.72)), breast cancer (0.56 (0.45–0.70)), and thyroid cancer (0.71 (0.59–0.85)) than for individuals in the no coffee group. Physical exercise of ≥150 min/week was correlated with higher odds for gastric cancer (1.18 (1.03–1.36)), colon cancer (1.52 (1.26–1.83)), breast cancer (1.53 (1.35–1.74)), thyroid cancer (1.42 (1.27–1.59)), and prostate cancer (1.61 (1.13–2.28)) compared to no exercise. Coffee consumption and physical exercise showed an interaction in thyroid cancer (p = 0.002). Coffee consumption was related to a decreased risk of gastric cancer, hepatic cancer, colon cancer, breast cancer, and thyroid cancer in the adult population. Physical exercise was positively correlated with gastric cancer, colon cancer, breast cancer, thyroid cancer, and prostate cancer.

Effects of Chlorogenic Acids on Menopausal Symptoms in Healthy Women: A Randomized, Placebo-Controlled, Double-Blind, Parallel-Group Trial

A reduction in estrogen levels in the perimenopausal and postmenopausal periods causes various symptoms in women, such as hot flushes, sweats, depression, anxiety, and insomnia. Chlorogenic acids (CGAs), which are phenolic compounds widely present in plants such as coffee beans, have various physiological functions. However, the effects of CGAs on menopausal symptoms are unknown. To examine the effects of CGAs on menopausal symptoms, especially hot flushes, a randomized, placebo-controlled, double-blind, parallel-group trial was conducted in healthy women. Eighty-two subjects were randomized and assigned to receive CGAs (270 mg) tablets or the placebo for 4 weeks. After 4 weeks of intake, the number of hot flushes, the severity of hot flushes during sleep, and the severity of daytime sweats decreased significantly in the CGA group compared to the placebo group. The modified Kupperman index for menopausal symptoms decreased significantly after 2 weeks in the CGA group compared to the placebo group. Adverse effects caused by CGAs were not observed. The results show that continuous intake of CGAs resulted in improvements in menopausal symptoms, especially hot flushes, in healthy women.

Effect of Chlorogenic Acids on Cognitive Function in Mild Cognitive Impairment: A Randomized Controlled Crossover Trial

BACKGROUND

Mild cognitive impairment (MCI) is a global-scale issue, due in large part to the rapidly growing elderly population. The main polyphenol contained in coffee beans, chlorogenic acid (CGA), improves attention in healthy individuals. The utility of CGAs for treating MCI, however, has not been evaluated.

OBJECTIVE

To determine the effects of continuous CGA intake on cognitive function, especially attention, in patients diagnosed with MCI.

METHODS

The study was a randomized controlled crossover trial including 34 patients with MCI. Participants were randomly divided into two groups: Those who first ingested a placebo beverage and those who first ingested an active beverage containing CGAs (553.6 mg/bottle) twice daily for 12 weeks. After a 4-week washout period, the subjects ingested the other beverage (i.e., placebo or active beverage) in the same manner. Endpoint measures included scores on the Japanese version of the Mini-Mental State Examination (MMSE), the Japanese version of the Alzheimer's Disease Assessment Scale-cognitive component (ADAS-cog) testing overall cognitive function, and the Japanese version of the Trail Making Test (TMT-A, TMT-B) testing attention, along with the results of blood tests to evaluate safety.

RESULTS

In the TMT-B test, participants had a significantly reduced number of errors while ingesting the CGA beverage as compared with the placebo beverage (p < 0.05), although there was no difference in test completion time. Scores in the MMSE, ADAS-cog, and TMT-A did not differ significantly between conditions.

CONCLUSION

Continuous intake of CGAs appears to improve attention and executive function among cognitive functions in MCI.