Melatonin in Mediterranean diet, a new perspective

Views and perspectives on the indoleamines serotonin and melatonin in plants: past, present and future

In the decades since their discovery in plants in the mid-to-late 1900s, melatonin (N-acetyl-5-methoxytryptamine) and serotonin (5-methoxytryptamine) have been established as their own class of phytohormone and have become popular targets for examination and study as stress ameliorating compounds. The indoleamines play roles across the plant life cycle from reproduction to morphogenesis and plant environmental perception. There is growing interest in harnessing the power of these plant neurotransmitters in applied and agricultural settings, particularly as we face increasingly volatile climates for food production; however, there is still a lot to learn about the mechanisms of indoleamine action in plants. A recent explosion of interest in these compounds has led to exponential growth in the field of melatonin research in particular. This concept paper aims to summarize the current status of indoleamine research and highlight some emerging trends.

Melatonin protects against diclofenac induced oxidative stress mediated myocardial toxicity in rats: A mechanistic insight

Diclofenac, a traditional non-steroidal anti-inflammatory drug, is commonly used for treating chronic pain and inflammation. Recently, a number of articles have highlighted the toxicities associated with diclofenac. The current study explores the molecular mechanism of diclofenac induced cardiac toxicity following oxidative stress. Diclofenac inhibits catalase, disrupts the redox balance in cardiac tissue, accelerates the monoamine oxidase induced hydroperoxide generation and eventually inhibits crucial mitochondrial enzyme, viz., aldehyde dehydrogenase, thereby causing myocardial injury. Melatonin, the pineal indoleamine with high antioxidative efficacy, is well known for its cardio-protective properties and its dietary consumption has profound impact on cardiac health. The present study demonstrates perhaps for the first time, that apart from ameliorating oxidative load in the cardiac tissue, melatonin also attenuates the inhibition of catalase and aldehyde dehydrogenase, and prevents stress mediated stimulation of monoamine oxidase. Moreover, favourable binding of diclofenac with melatonin may protect the myocardium from the deleterious effects of this drug. The results indicate toward a novel mechanism of protection by melatonin, having future therapeutic relevance.

Survey on patients' attitude towards the nutritional counselling in the dental setting

AIM

A healthy diet could help to prevent both oral and systemic diseases, with dentists and nutritionists supplementing their skills. The dental setting, where patients periodically refer to seeking oral health care, represents a powerful opportunity for nutritional counselling. To the best of our knowledge, no study is available on patients' attitudes towards dietary counselling in the dental setting. This cross-sectional study investigates patients' attitude towards receiving nutritional support within the dental setting and it elucidates whether a transdisciplinary approach would be well accepted.

MATERIALS AND METHODS

A questionnaire was administered to patients attending three different clinics: a private clinic, a hospital dental clinic of the national healthcare system and the private dental practice within the same hospital.

RESULTS

Three hundred thirteen questionnaires were collected. Most dental patients acknowledged receiving nutritional advice from both dentists and nutritionists. The nutritionist within the dental setting was positively perceived, providing useful advice to prevent oral and systemic diseases and also drawing up a diet with periodic follow-ups.

DISCUSSION AND CONCLUSION

These findings support the positive attitude of patients towards receiving nutritional counselling within the dental setting. The dental clinics can be pivotal in oral and systemic disease screening and prevention and a multidisciplinary approach is highly encouraged.

Cocoa as immunomodulatory agent: an update

Cocoa is rich in polyphenols, mainly flavonoids, which correlate with several health benefits mediated by their antioxidant, anti-inflammatory and immunomodulatory properties. Cocoa and chocolate consumption have been reported to impact the regulation of the immune system, both in preclinical studies and in human trials. The mechanisms for immunomodulation can involve different effects of cocoa polyphenols on the immune system, acting as anti-inflammatory, antioxidant and anti-allergic agents, as well as the direct influence of cocoa on innate and acquired immunity, with cytokines production and activation of both lymphocyte-dependent and -independent pathways. Cocoa intake has been also correlated to changes in gut microbiota ecology and composition, also affecting the intestinal immune system. This review summarises the updates of the last two decades on cocoa as immunomodulatory agent and explores the health-related benefits of cocoa and chocolate intake.

The melatonin contained in beer can provide health benefits, due to its antioxidant, anti-inflammatory and immunomodulatory properties

Beer is a fermented beverage with a low alcohol content originating from cereal fermentation (barley or wheat). It forms part of the diet for many people. It contains melatonin (N-acetyl-5-methoxytryptamine). Melatonin is a molecule with a wide range of antioxidant, oncostatic, immunomodulatory, and cytoprotective properties. The aim of this work was to review the data supporting the idea that a moderate consumption of beer, because of its melatonin content, is particularly useful in healthy diets and in other physiological situations (such as pregnancy, menopause, and old age). Data source: a) The MEDLINE /PubMed search was conducted from 1975 to April 2022, and b) Our own experience and published studies on melatonin, the immune system, and beer. We provide a review of research on the mechanisms of melatonin generation in beer, its concentrations, and its possible effects on health. The melatonin contained in beer, as part of a healthy diet and in some special physiological situations, could act as a protective factor and improve the quality of life of those who drink it in moderation. © 2022 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Mediterranean Diet and Melatonin: A Systematic Review

The Mediterranean diet (MD) has beneficial effects on human health, which is evidenced by the observation of lower incidence rates of chronic diseases in Mediterranean countries. The MD dietary pattern is rich in antioxidants, such as melatonin, which is a hormone produced mainly by the pineal gland and controls several circadian rhythms. Additionally, melatonin is found in foods, such as fruit and vegetables. The purpose of this systematic review was to assess the melatonin content in Mediterranean foods and to evaluate the influence of the MD on melatonin levels in both humans and model organisms. A comprehensive search was conducted in four databases (PubMed, Scopus, Cochrane Library and Web of Science) and data were extracted. A total of 31 records were chosen. MD-related foods, such as tomatoes, olive oil, red wine, beer, nuts, and vegetables, showed high melatonin contents. The consumption of specific MD foods increases melatonin levels and improves the antioxidant status in plasma.

Non-saccharomyces yeast probiotics: revealing relevance and potential

Non-Saccharomyces yeasts are unicellular eukaryotes that play important roles in diverse ecological niches. In recent decades, their physiological and morphological properties have been reevaluated and reassessed, demonstrating the enormous potential they possess in various fields of application. Non-Saccharomyces yeasts have gained relevance as probiotics, and in vitro and in vivo assays are very promising and offer a research niche with novel applications within the functional food and nutraceutical industry. Several beneficial effects have been described, such as antimicrobial and antioxidant activities and gastrointestinal modulation and regulation functions. In addition, several positive effects of bioactive compounds or production of specific enzymes have been reported on physical, mental and neurodegenerative diseases as well as on the organoleptic properties of the final product. Other points to highlight are the multiomics as a tool to enhance characteristics of interest within the industry; as well as microencapsulation offer a wide field of study that opens the niche of food matrices as carriers of probiotics; in turn, non-Saccharomyces yeasts offer an interesting alternative as microencapsulating cells of various compounds of interest.

Is Melatonin the "Next Vitamin D"?: A Review of Emerging Science, Clinical Uses, Safety, and Dietary Supplements

Melatonin has become a popular dietary supplement, most known as a chronobiotic, and for establishing healthy sleep. Research over the last decade into cancer, Alzheimer's disease, multiple sclerosis, fertility, PCOS, and many other conditions, combined with the COVID-19 pandemic, has led to greater awareness of melatonin because of its ability to act as a potent antioxidant, immune-active agent, and mitochondrial regulator. There are distinct similarities between melatonin and vitamin D in the depth and breadth of their impact on health. Both act as hormones, affect multiple systems through their immune-modulating, anti-inflammatory functions, are found in the skin, and are responsive to sunlight and darkness. In fact, there may be similarities between the widespread concern about vitamin D deficiency as a "sunlight deficiency" and reduced melatonin secretion as a result of "darkness deficiency" from overexposure to artificial blue light. The trend toward greater use of melatonin supplements has resulted in concern about its safety, especially higher doses, long-term use, and application in certain populations (e.g., children). This review aims to evaluate the recent data on melatonin's mechanisms, its clinical uses beyond sleep, safety concerns, and a thorough summary of therapeutic considerations concerning dietary supplementation, including the different formats available (animal, synthetic, and phytomelatonin), dosing, timing, contraindications, and nutrient combinations.

Adherence to Lifelines Diet Score (LLDS) Is Associated with a Reduced Risk of Breast Cancer (BrCa): A Case-Control Study

BACKGROUND

Previous evidence suggests a link between diet quality and breast cancer (BrCa); however, the link between the Lifelines Diet Score (LLDS)-a fully food-based score that uses the 2015 Dutch Dietary Guidelines-and risk of BrCa has not yet been evaluated. Therefore, the aim of this study was to observe the relationship between adherence to an LLDS and risk of BrCa in Iranian adults.

METHODS

In the hospital-based case-control study, 253 patients with BrCa and 267 non-BrCa controls were enrolled. Individual's food consumption was recorded to calculate LLDS using a semiquantitative food frequency questionnaire. In adjusted models, the association between the inflammatory potential of the diet and the risk of BrCa was estimated by using binary logistic regression.

RESULTS

Compared with control individuals, BrCa patients significantly had higher waist circumference (WC), first pregnancy age, abortion history, and number of children. In addition, the mean intake of vitamin D supplements and anti-inflammatory drugs in the case group was significantly lower than the control group. Furthermore, after adjusted potential confounders, individuals in the highest vs. lowest quartiles of LLDS showed statistically significant lower risk of BrCa in overall population (OR: 0.21; 95% CI: 0.11-0.43; P trend <0.001), premenopausal (OR: 0.26; 95% CI: 0.10-0.68; P trend = 0.003), and post-menopausal women (OR: 0.20; 95% CI: 0.06-0.60; P trend = 0.015).

CONCLUSION

Findings of this study reflected that higher LLDS decreased risk of BrCa, but need further investigation in later studies.

The Relationship Between Diet and Sleep in Older Adults: a Narrative Review

PURPOSE OF REVIEW

Older adults more frequently experience reduced sleep quality and quantity compared to younger adults. Diet is one modifiable lifestyle factor that may influence sleep outcomes in older adults. The purpose of this review is to synthesise the current literature investigating the impact of diet, including foods and nutrients, on the sleep quality and quantity of older adults.

RECENT FINDINGS

Overall, the observational and intervention studies suggest that following a Mediterranean diet, and the consumption of certain food items (e.g. milk), and nutrients (e.g. vitamin D and vitamin E) may influence (improve or reduce) sleep quality and quantity. This review describes the potential efficacy for dietary factors to improve sleep outcomes in older adults. However, given the heterogeneity of included studies in this review (i.e. aims, methodologies, and outcomes assessed), it is difficult to consolidate the available evidence to make specific recommendations. More targeted research exploring the relationship between diet and sleep in older adults is needed to strengthen the current evidence base.

Adherence to Lifelines Diet Score (LLDS) is associated with better sleep quality in overweight and obese women

PURPOSE

Previous studies have shown the connection between diet quality to sleep quality and weight status, although the relationship between Lifelines Diet Score (LLDS)-a fully food-based score that uses the 2015 Dutch Dietary Guidelines and underlying international literature-and sleep quality has not been evaluated in overweight and obese individuals yet. This observational study was conducted on overweight and obese adult females to assess the relationship between adherence to a LLDS pattern and sleep quality in Iran.

METHODS

A cohort of 278 overweight and obese women aged above 18 years was enrolled and their dietary intake was assessed using a 147-item, semi-quantitative, validated food frequency questionnaire. Pittsburgh Sleep Quality Index (PSQI), a self-reported questionnaire including 19-items, was applied to estimate sleep quality among the target population. Diet quality indices (LLDS) were calculated using the P.C. Vinke, et al. method, based on the 2015 Dutch Dietary Guidelines and the underlying literature.

RESULTS

Subjects in the highest LLDS tertile (those who had adhered closely to the food-based score) were older, compared to the lowest tertile (37.57 ± 7.77 versus 34.57 ± 9; p = 0.01). It was shown that about 25.5% of our subjects have poor quality sleep and 39% have better sleep quality which were mostly in the third tertile with greater LLDS. The parallel values in the first tertile were 29.9% and 46.8%, respectively (p = 0.02). Binary logistic regression was applied to evaluate the association between adherence of LLDS and sleep quality. The result has shown that the LLDS were correlated with lower risk poor sleep quality, wherein those who were in higher tertile (higher adherence to LLDS) had better sleep quality (odds ratio [OR]:0.586, 95% confidence interval [CI] (0.285-1.207), p = 0.009) and the result was not affected by adjusting for potential cofounders including age, education levels, and economic levels, sleep quality remained significantly associated with [OR]: 0.531, 95% confidence interval [CI] (0.248-1.138, p = 0.014).

CONCLUSIONS

From this observational study, the higher LLDS can be related with better sleep quality in overweight and obese women.

LEVEL OF EVIDENCE

Level IV, evidence obtained from multiple time series with or without the intervention, such as case studies.

The role of high-density lipoprotein cholesterol, apolipoprotein A and paraoxonase-1 in the pathophysiology of neuroprogressive disorders

Lowered high-density lipoprotein (HDL) cholesterol has been reported in major depressive disorder, bipolar disorder, first episode of psychosis, and schizophrenia. HDL, its major apolipoprotein component, ApoA1, and the antioxidant enzyme paraoxonase (PON)1 (which is normally bound to ApoA1) all have anti-atherogenic, antioxidant, anti-inflammatory, and immunomodulatory roles, which are discussed in this paper. The paper details the pathways mediating the anti-inflammatory effects of HDL, ApoA1 and PON1 and describes the mechanisms leading to compromised HDL and PON1 levels and function in an environment of chronic inflammation. The molecular mechanisms by which changes in HDL, ApoA1 and PON1 might contribute to the pathophysiology of the neuroprogressive disorders are explained. Moreover, the anti-inflammatory actions of ApoM-mediated sphingosine 1-phosphate (S1P) signalling are reviewed as well as the deleterious effects of chronic inflammation and oxidative stress on ApoM/S1P signalling. Finally, therapeutic interventions specifically aimed at improving the levels and function of HDL and PON1 while reducing levels of inflammation and oxidative stress are considered. These include the so-called Mediterranean diet, extra virgin olive oil, polyphenols, flavonoids, isoflavones, pomegranate juice, melatonin and the Mediterranean diet combined with the ketogenic diet.

Assessment of Melatonin and Its Precursors Content by a HPLC-MS/MS Method from Different Romanian Wines

Because melatonin has strong antioxidant activity and wine is an alcoholic beverage of economic relevance, in the present work, the impact of some variable parameters that may occur in the winemaking process on the concentrations of melatonin and its precursors in Romanian wines was studied. Therefore, a sensitive and selective high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method was developed for the simultaneous analysis of melatonin, serotonin, and l-tryptophan, and some method performance parameters including selectivity, detection limit, precision (by comparing with an alternative HPLC-FL method), accuracy, and robustness were validated. These determinations are significant and the final amounts of analytes are dependent on the microorganisms involved in the winemaking process, the grape variety, geographic regions of vineyards, and aging of wines. In the future, the method may be useful to increase the melatonin content and the antioxidant activity in wines by improved steps in the winemaking process, especially based on application of selected yeasts and improved fermentation conditions.

Simultaneous determination of melatonin and trans-resveratrol in wine by dispersive liquid-liquid microextraction followed by HPLC-FLD

The discovery of melatonin (Mel) in wines triggered a new interest in the paradigm of health benefits and wine consumption, usually ascribed to trans-resveratrol (trans-RSV). In this context, a dispersive liquid-liquid microextraction for the analysis of Mel and trans-RSV in wines by LC-FLD was developed. A 2^6-1 factorial design was used to identify the significant variables (p < 0.05) and Central Composite Design was used to achieve the optimal conditions: 300 µL of chloroform (extracting solvent), 1500 µL of acetonitrile (disperser solvent) and 1500 mg of NaCl (ionic strength). Excellent linearity (R² > 0.9999), repeatability (<3.55%), and accuracy (<7.18%) were obtained using a blank matrix and recoveries (>91.9%) using wines. The method was successfully applied to the analyses of Mel (0.63-7.44 ng mL^-1) and trans-RSV (169-2616 ng mL^-1) in different wine varieties. Comparison with literature point the overall advantages of the new method.

Bioavailability of Melatonin from Lentil Sprouts and Its Role in the Plasmatic Antioxidant Status in Rats

Melatonin is a multifunctional antioxidant neurohormone found in plant foods such as lentil sprouts. We aim to evaluate the effect of lentil sprout intake on the plasmatic levels of melatonin and metabolically related compounds (plasmatic serotonin and urinary 6-sulfatoxymelatonin), total phenolic compounds, and plasmatic antioxidant status, and compare it with synthetic melatonin. The germination of lentils increases the content of melatonin. However, the phenolic content diminished due to the loss of phenolic acids and flavan-3-ols. The flavonol content remained unaltered, being the main phenolic family in lentil sprouts, primarily composed of kaempferol glycosides. Sprague Dawley rats were used to investigate the pharmacokinetic profile of melatonin after oral administration of a lentil sprout extract and to evaluate plasma and urine melatonin and related biomarkers and antioxidant capacity. Melatonin showed maximum concentration (45.4 pg/mL) 90 min after lentil sprout administration. The plasmatic melatonin levels increased after lentil sprout intake (70%, p < 0.05) with respect to the control, 1.2-fold more than after synthetic melatonin ingestion. These increments correlated with urinary 6-sulfatoxymelatonin content (p < 0.05), a key biomarker of plasmatic melatonin. Nonetheless, the phenolic compound content did not exhibit any significant variation. Plasmatic antioxidant status increased in the antioxidant capacity upon both lentil sprout and synthetic melatonin administration. For the first time, we investigated the bioavailability of melatonin from lentil sprouts and its role in plasmatic antioxidant status. We concluded that their intake could increase melatonin plasmatic concentration and attenuate plasmatic oxidative stress.

Cluster bagging promotes melatonin biosynthesis in the berry skins of Vitis vinifera cv. Cabernet Sauvignon and Carignan during development and ripening

Melatonin, a tryptophan derivative, is an important functional component in grape berries. We investigated the effect of cluster bagging on melatonin biosynthesis in the berries of two wine grape cultivars, Cabernet Sauvignon and Carignan, during fruit development and ripening. Cluster bagging delayed fruit coloring and ripening, and bag-treated berries of both grape cultivars synthesized more melatonin and most of the precursor compounds including L-tryptophan, N-acetylserotonin, tryptamine, and serotonin compared to those exposed to light (control) conditions. Interestingly, 5-methoxytryptamine was only detected in the berries of Carignan and not of Cabernet Sauvignon, both in the cluster bagging and control groups. In addition, melatonin and most of its precursors, decreased after veraison. VvSNAT1 and VvT5H expression levels were positively correlated with melatonin content. Our findings suggested that melatonin synthesis pathways differ among grape cultivars, and that VvSNAT1 and VvT5H may show key regulatory roles in the melatonin synthesis of grape berries.

Food intake biomarkers for apple, pear, and stone fruit

Fruit is a key component of a healthy diet. However, it is still not clear whether some classes of fruit may be more beneficial than others and whether all individuals whatever their age, gender, health status, genotype, or gut microbiota composition respond in the same way to fruit consumption. Such questions require further observational and intervention studies in which the intake of a specific fruit can be precisely assessed at the population and individual levels. Within the Food Biomarker Alliance Project (FoodBAll Project) under the Joint Programming Initiative “A Healthy Diet for a Healthy Life”, an ambitious action was undertaken aiming at reviewing existent literature in a systematic way to identify validated and promising biomarkers of intake for all major food groups, including fruits. This paper belongs to a series of reviews following the same BFIRev protocol and is focusing on biomarkers of pome and stone fruit intake. Selected candidate biomarkers extracted from the literature search went through a validation process specifically developed for food intake biomarkers.

Effect of Red Wine Intake on Serum and Salivary Melatonin Levels: A Randomized, Placebo-Controlled Clinical Trial

Melatonin (MLT) is a recently discovered phytochemical in wine, but its influence on physiological MLT levels is still unknown. This study aimed at evaluating variations, in serum and saliva, of MLT concentrations after the intake of MLT-enriched red wine. Twelve healthy volunteers were recruited to receive 125 mL of red wine naturally lacking of MLT (placebo, PLC), or the same wine enriched with MLT (MLT+). A physiological steady decline of serum MLT was observed from baseline up to 90 min, for both wines. After PLC intake, the decrease was significantly faster than the one occurring after MLT+ wine, which thus delayed the drop down of serum MLT with a plateau at 30⁻60 min. Salivary MLT levels slightly peaked at 45 min after MLT+ wine intake, without statistical significance. Therefore, the intake of a glass of MLT-enriched red wine changed serum levels of the indoleamine, supporting the role of wine MLT in counteracting the physiological decline of the hormone into the bloodstream.

Cardiovascular Benefits of Dietary Melatonin: A Myth or a Reality?

The role of the diet as well as the impact of the dietary habits on human health and disease is well established. Apart from its sleep regulatory effect, the indoleamine melatonin is a well-established antioxidant molecule with multiple health benefits. Convincing evidence supports the presence of melatonin in plants and foods with the intake of such foods affecting circulating melatonin levels in humans. While numerous actions of both endogenous melatonin and melatonin supplementation are well described, little is known about the influence of the dietary melatonin intake on human health. In the present review, evidence for the cardiovascular health benefits of melatonin supplementation and dietary melatonin is discussed. Current knowledge on the biological significance as well as the underlying physiological mechanism of action of the dietary melatonin is also summarized. Whether dietary melatonin constitutes an alternative preventive treatment for cardiovascular disease is addressed.

Berry Phenolic Antioxidants - Implications for Human Health?

Antioxidants present in the diet may have a significant effect on the prophylaxis and progression of various diseases associated with oxidative stress. Berries contain a range of chemical compounds with antioxidant properties, including phenolic compounds. The aim of this review article is to provide an overview of the current knowledge of such phenolic antioxidants, and to discuss whether these compounds may always be natural gifts for human health, based on both in vitro and in vivo studies. It describes the antioxidant properties of fresh berries (including aronia berries, grapes, blueberries, sea buckthorn berries, strawberries and other berries) and their various products, especially juices and wines. Some papers report that these phenolic compounds may sometimes behave like prooxidants, and sometimes demonstrate both antioxidant and prooxidant activity, while others note they do not behave the same way in vitro and in vivo. However, no unwanted or toxic effects (i.e., chemical, hematological or urinary effect) have been associated with the consumption of berries or berry juices or other extracts, especially aronia berries and aronia products in vivo, and in vitro, which may suggest that the phenolic antioxidants found in berries are natural gifts for human health. However, the phenolic compound content of berries and berry products is not always well described, and further studies are required to determine the therapeutic doses of different berry products for use in future clinical studies. Moreover, further experiments are needed to understand the beneficial effects reported so far from the mechanistic point of view. Therefore, greater attention should be paid to the development of well-controlled and high-quality clinical studies in this area.

Effect of the Mediterranean diet on cognition and brain morphology and function: a systematic review of randomized controlled trials

Background

Observational studies of the Mediterranean diet suggest cognitive benefits, potentially reducing dementia risk.

Objective

We performed the first published review to our knowledge of randomized controlled trials (RCTs) investigating Mediterranean diet effects on cognition or brain morphology and function, with an additional focus on intervention diet quality and its relation to "traditional" Mediterranean dietary patterns.

Design

We searched 9 databases from inception (final update December 2017) for RCTs testing a Mediterranean compared with alternate diet for cognitive or brain morphology and function outcomes.

Results

Analyses were based on 66 cognitive tests and 1 brain function outcome from 5 included studies (n = 1888 participants). The prescribed Mediterranean diets varied considerably between studies, particularly with regards to quantitative food advice. Only 8/66 (12.1%) of individual cognitive outcomes at trial level significantly favored a Mediterranean diet for cognitive performance, with effect sizes (ESs) ranging from small (0.32) to large (1.66), whereas 2 outcomes favored controls. Data limitations precluded a meta-analysis. Of 8 domain composite cognitive scores from 2 studies, the 3 (Memory, Frontal, and Global function) from PREDIMED (PREvención con DIeta MEDiterránea) were significant, with ESs ranging from 0.39 to 1.29. A posttest comparison at a second PREDIMED site found that the Mediterranean diet modulates the effect of several genotypes associated with dementia risk for some cognitive outcomes, with mixed results. Finally, the risk of low-plasma brain-derived neurotrophic factor was reduced by 78% (OR = 0.22; 95% CI: 0.05, 0.90) in those who consumed a Mediterranean diet compared to control diet at 3 y in this trial. There was no benefit of the Mediterranean diet for incident cognitive impairment or dementia.

Conclusions

Five RCTs of the Mediterranean diet and cognition have been published to date. The data are mostly nonsignificant, with small ESs. However, the significant improvements in cognitive domain composites in the most robustly designed study warrant additional research.

Protective Role of Intracellular Melatonin Against Oxidative Stress and UV Radiation in Saccharomyces cerevisiae

Melatonin (Mel) is considered a potent natural antioxidant molecule given its free-radical scavenging ability. Its origin is traced back to the origin of aerobic life as early defense against oxidative stress and radiation. More complex signaling functions have been attributed to Mel as a result of evolution in different biological kingdoms, which comprise gene expression modulation, enzyme activity, and mitochondrial homeostasis regulation processes, among others. Since Mel production has been recently reported in wine yeast, we tested the protective effect of Mel on Saccharomyces cerevisiae against oxidative stress and UV light. As the optimal conditions for S. cerevisiae to synthesize Mel are still unknown, we developed an intracellular Mel-charging method to test its effect against stresses. To assess Mel’s ability to protect S. cerevisiae from both stresses, we ran growth tests in liquid media and viability assays by colony count after Mel treatment, followed by stress. We also analyzed gene expression by qPCR on a selection of genes involved in stress protection in response to Mel treatment under oxidative stress and UV radiation. The viability in the Mel-treated cells after H₂O₂ stress was up to 35% greater than for the untreated controls, while stress amelioration reached 40% for UVC light (254 nm). Mel-treated cells showed a significant shortened lag phase compared to the control cells under the stress and normal growth conditions. The gene expression analysis showed that Mel significantly modulated gene expression in the unstressed cells in the exponential growth phase, and also during various stress treatments.

Plants of the Genus Zingiber as a Source of Bioactive Phytochemicals: From Tradition to Pharmacy

Plants of the genus Zingiber (Family Zingiberaceae) are widely used throughout the world as food and medicinal plants. They represent very popular herbal remedies in various traditional healing systems; in particular, rhizome of Zingiber spp. plants has a long history of ethnobotanical uses because of a plethora of curative properties. Antimicrobial activity of rhizome essential oil has been extensively confirmed in vitro and attributed to its chemical components, mainly consisting of monoterpene and sesquiterpene hydrocarbons such as α-zingiberene, ar-curcumene, β-bisabolene and β-sesquiphellandrene. In addition, gingerols have been identified as the major active components in the fresh rhizome, whereas shogaols, dehydrated gingerol derivatives, are the predominant pungent constituents in dried rhizome. Zingiber spp. may thus represent a promising and innovative source of natural alternatives to chemical food preservatives. This approach would meet the increasing concern of consumers aware of the potential health risks associated with the conventional antimicrobial agents in food. This narrative review aims at providing a literature overview on Zingiber spp. plants, their cultivation, traditional uses, phytochemical constituents and biological activities.

Melatonin: Protection against age-related cardiac pathology

Aging is a complex and progressive process that involves physiological and metabolic deterioration in every organ and system. Cardiovascular diseases are one of the most common causes of mortality and morbidity among elderly subjects worldwide. Most age-related cardiovascular disorders can be influenced by modifiable behaviours such as a healthy diet rich in fruit and vegetables, avoidance of smoking, increased physical activity and reduced stress. The role of diet in prevention of various disorders is a well-established factor, which has an even more important role in the geriatric population. Melatonin, an indoleamine with multiple actions including antioxidant properties, has been identified in a very large number of plant species, including edible plant products and medical herbs. Among products where melatonin has been identified include wine, olive oil, tomato, beer, and others. Interestingly, consumed melatonin in plant foods or melatonin supplementation may promote health benefits by virtue of its multiple properties and it may counteract pathological conditions also related to cardiovascular disorders, carcinogenesis, neurological diseases and aging. In the present review, we summarized melatonin effects against age-related cardiac alterations and abnormalities with a special focus on heart ischemia/reperfusion (IR) injury and myocardial infarction.

Melatonin in Edible and Non-Edible Plants

The concept of melatonin has become more important recently both in plants and in human who utilize plants for nutritional and health purposes. Melatonin, synthesized from L-tryptophan by enzyms, protects plants against difficult conditions. People have consumed these plants for their antioxidant, immunomodulator, antiinflammatory and anticancer effects. In parts of edible and non-edible plants, levels of melatonin are determined by cyclodextrin-modified micellar electrokinetic chromatography, enzyme-linked immuno sorbent assay, radioimmunoassay, high-performance liquid chromatography, liquid chromatography with electrochemical detection, liquid chromatography with fluorimetric detection, liquid chromatography-mass spectrometry, and liquid chromatography-ultraviolet spectrophotometry. In this review, biosynthesis of melatonin in both animal and plants, function of melatonin in plant kingdom, especially in medicinal/edible and nonedible plants, and detection of phytomelatonin content in those plants are presented.

Changes over time in mental well-being, fruit and vegetable consumption and physical activity in a community-based lifestyle intervention: a before and after study

OBJECTIVES

There is a theoretical basis for believing that healthy lifestyle interventions can improve mental well-being and evidence to show that mental well-being is protective of future health. This study contributes to the evidence base by examining changes in mental well-being associated with the One Body One Life (OBOL) healthy lifestyle programme in a community setting in the West Midlands.

STUDY DESIGN

Quantitative, before and after the evaluation.

METHODS

We conducted a before and after study of the lifestyle intervention 'OBOL', a multi component intervention that includes exercise and healthy eating education. Mental well-being was measured with the Warwick-Edinburgh Mental Well-being Scale. Physical activity and fruit and vegetable consumption were self-reported. Measures were collected before and after the 12-week intervention and three months post completion. Non-parametric tests were used to assess differences between groups, and linear mixed models were used to assess change over time.

RESULTS

Four hundred and eighty-one (81% of attendees) adult participants completed a valid Warwick-Edinburgh Mental Well-being Scale before starting OBOL; of whom, 63.8% completed the Warwick-Edinburgh Mental Well-being Scale immediately post intervention and 25.2% at three months. Mental well-being levels increased significantly (P < 0.001) over the course of the intervention and were sustained at the three-month follow-up (baseline median Warwick-Edinburgh Mental Well-being Scale score = 48 [interquartile range 41-55], completion = 53 [interquartile range 46-57], 3-month follow-up = 52 [interquartile range 46-56]). Change in mental well-being was clinically significant after accounting for age and gender. Changes in both fruit and vegetable consumption and physical activity appeared to explain some but not all of the variation in mental well-being.

CONCLUSION

We found significant improvements in mental well-being among participants directly after the intervention which were sustained at the three-month follow-up. These findings contribute to a growing body of knowledge on the contribution of lifestyle interventions to promoting and sustaining mental well-being.

Intake of bean sprouts influences melatonin and antioxidant capacity biomarker levels in rats

Melatonin is an endogenous antioxidant hormone, which reduces with ageing and the low levels are associated with some chronic diseases. Germination of legumes increases the plant levels of melatonin, making sprouts a suitable food source of this hormone. However, information on its bioavailability after consumption is lacking. We aimed to evaluate in rats the effect of kidney bean sprout intake on the plasma levels of melatonin and metabolically related compounds (serotonin, 6-sulfatoxymelatonin), total phenolic compounds and total antioxidant capacity. In addition, we compared the plasma bioavailability derived from kidney bean sprouts versus synthetic melatonin intake. Kidney beans were germinated for 6 days and an extract was prepared in water. Male young Sprague Dawley rats were used; blood and urine samples were obtained before and after 90 min of administration of kidney bean sprout extract via a gavage. The plasmatic melatonin levels increased after sprout ingestion (16%, p < 0.05). This increment correlated with the urinary 6-sulfatoxymelatonin content, the principal biomarker of plasmatic melatonin levels (p < 0.01). Nevertheless, the phenolic compounds and antioxidant capacity levels did not exhibit any significant variation. The comparison of the bioavailability between the melatonin contained in the kidney bean sprouts and in a synthetic solution evidenced slightly higher levels of plasmatic melatonin (17%) in rats fed with the solution of synthetic melatonin. We conclude that kidney bean sprouts could be a good source of dietary melatonin and other bioactive compounds known to have health benefits.

Putative Role of Red Wine Polyphenols against Brain Pathology in Alzheimer's and Parkinson's Disease

Alzheimer's disease (AD) and Parkinson's disease (PD) are the most common age-related neurodegenerative disorders and hence pose remarkable socio-economical burdens to both families and state. Although AD and PD have different clinical and neuropathological features, they share common molecular mechanisms that appear to be triggered by multi-factorial events, such as protein aggregation, mitochondrial dysfunction, oxidative stress (OS), and neuroinflammation, ultimately leading to neuronal cell death. Currently, there are no established and validated disease-modifying strategies for either AD or PD. Among the various lifestyle factors that may prevent or slow age-related neurodegenerative diseases, epidemiological studies on moderate consumption of red wine, especially as part of a holistic Mediterranean diet, have attracted increasing interest. Red wine is particularly rich in specific polyphenolic compounds that appear to affect the biological processes of AD and PD, such as quercetin, myricetin, catechins, tannins, anthocyanidins, resveratrol, and ferulic acid. Indeed, there is now a consistent body of in vitro and in vivo data on the neuroprotective effects of red wine polyphenols (RWP) showing that they do not merely possess antioxidant properties, but may additionally act upon, in a multi-target manner, the underlying key mechanisms featuring in both AD and PD. Furthermore, it is important that bioavailability issues are addressed in order for neuroprotection to be relevant in a clinical study scenario. This review summarizes the current knowledge about the major classes of RWP and places into perspective their potential to be considered as nutraceuticals to target neuropathology in AD and PD.

The Impact of Melatonin in Research

Citation indexes represent helpful tools for evaluating the impact of articles on research. The aim of this study was to obtain the top-100 ranking of the most cited papers on melatonin, a relevant neurohormone mainly involved in phase-adjusting the biological clock and with certain sleep-promoting capability. An article search was carried out on the Institute for Scientific Information (ISI) Web of Science platform. Numbers of citations, names of authors, journals and their 2014-impact factor, year of publication, and experimental designs of studies were recorded. The ranking of the 100-most cited articles on melatonin research (up to February 2016) revealed a citation range from 1623 to 310. Narrative reviews/expert opinions were the most frequently cited articles, while the main research topics were oxidative stress, sleep physiology, reproduction, circadian rhythms and melatonin receptors. This study represents the first detailed analysis of the 100 top-cited articles published in the field of melatonin research, showing its impact and relevance in the biomedical field.

Yeast contribution to melatonin, melatonin isomers and tryptophan ethyl ester during alcoholic fermentation of grape musts

Melatonin (MEL) has been found in some medicinal and food plants, including grapevine, a commodity of particular interest for the production of wine, a beverage of economic relevance. It has also been suggested that MEL in wine may, at least in part, contribute to the health-promoting properties attributed to this beverage and, possibly, to other traditional Mediterranean foodstuffs. After a preliminary screening of 9 yeast strains in laboratory medium, three selected strains (Saccharomyces cerevisiae EC1118, Torulaspora delbrueckii CBS1146(T) and Zygosaccharomyces bailii ATCC36947(T) ) were inoculated in experimental musts obtained from 2 white (Moscato and Chardonnay) and 2 red (Croatina and Merlot) grape varieties. The production of MEL, melatonin isomers (MIs) and tryptophan ethyl ester (TEE) was monitored during the alcoholic fermentation. The screening showed that the three investigated strains produced the highest concentrations of MEL and two MIs in optimal growth conditions. However, MEL and MIs were not produced in oenological conditions, but the three strains synthesized high concentrations of a new MI and TEE in musts.