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Physiology & Behavior Oct 2022Lutein and zeaxanthin-xanthophyll carotenoids with antioxidant and anti-inflammatory characteristics-are present in the retina and the brain. High concentrations of... (Review)
Review
Lutein and zeaxanthin-xanthophyll carotenoids with antioxidant and anti-inflammatory characteristics-are present in the retina and the brain. High concentrations of these carotenoids have been positively related to cognitive performance. Therefore, this systematic review analyses the relationship between macular pigment density and cognitive functions. Most relevant databases were scoured for studies on healthy people relating cognitive functions to macular pigment optical density (MPOD). There were no age, sex, or race limitations. PROSPERO registration: CRD42021254833. Nineteen studies were included, seven randomized controlled trials (RCT) and eleven observational studies. The general aim of the studies was to examine the association between carotenoids (lutein, meso‑zeaxanthin and zeaxanthin) and cognitive function. Most observational studies correlates MPOD levels with cognitive function or brain activity. Besides, RCTs compared the cognitive function and/or brain activity after increasing lutein and zeaxanthin intake though dietary supplementation or avocado consumption. Dietary lutein and zeaxanthin intake increased MPOD in six of the seven clinical trials and significantly improved most of the cognitive functions studied. A wide variety of test and methodologies for measuring cognitive functions were observed. Memory, processing speed, attention and reasoning were the cognitive function significantly related to MPOD levels in adults. Brain activity also was related to MPOD, but the results were inconsistent. Only four of the eleven observational studies were based on young people and all studies showed a significant relationship between MPOD and cognitive functions. This systematic review showed a direct relationship among cognitive functions, macular pigment and the intake of lutein and zeaxanthin.
Topics: Adolescent; Adult; Cognition; Dietary Supplements; Humans; Lutein; Macular Pigment; Zeaxanthins
PubMed: 35752349
DOI: 10.1016/j.physbeh.2022.113891 -
Nutrients Oct 2022: Age-related macular degeneration (AMD) is a neurodegenerative ophthalmic disease. The purpose of this systematic review (SR) and meta-analysis was to evaluate if... (Meta-Analysis)
Meta-Analysis Review
: Age-related macular degeneration (AMD) is a neurodegenerative ophthalmic disease. The purpose of this systematic review (SR) and meta-analysis was to evaluate if dietary supplementation alone or in combinations might delay the progression of any of the stages of AMD. A SR and meta-analysis identifying cohort studies and randomized controlled trials (RCTs) evaluating the effect of supplements in patients diagnosed with AMD. PubMed, Scopus, Web of Science, CINAHL, and Cochrane were searched through 8th October 2021. Twenty studies, examining 5634 participants ranging from 55 to 80 years, were included in the SR. Eight studies were selected for meta-analysis (414 and 216 subjects in the intervention and control groups). Lutein and zeaxanthin plus -3 long-chain polyunsaturated fatty acids (-3 LC-PUFA) supplementation showed significant improvements in best-corrected visual acuity (BCVA) (SMD: -1.99, 95% CI: -3.33, -0.65) compared to the control group. Multifocal electroretinogram results (mfERG) were significantly improved overall (SMD: 4.59, 95% CI: 1.75, 7.43) after lutein plus zeaxanthin supplementation. Combinations of lutein and zeaxanthin with -3 LC-PUFA might be beneficial in preventing AMD progression and deterioration of visual function. Our results encourage initiating further studies with combinations of -3 LC-PUFA, lutein, and zeaxanthin especially in early AMD patients.
Topics: Humans; Zeaxanthins; Lutein; Xanthophylls; Visual Acuity; Double-Blind Method; Macular Degeneration; Dietary Supplements; Fatty Acids, Omega-3
PubMed: 36296956
DOI: 10.3390/nu14204273 -
The Cochrane Database of Systematic... Jul 2020Mycosis fungoides (MF) is the most common type of cutaneous T-cell lymphoma, a malignant, chronic disease initially affecting the skin. Several therapies are available,... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Mycosis fungoides (MF) is the most common type of cutaneous T-cell lymphoma, a malignant, chronic disease initially affecting the skin. Several therapies are available, which may induce clinical remission for a time. This is an update of a Cochrane Review first published in 2012: we wanted to assess new trials, some of which investigated new interventions.
OBJECTIVES
To assess the effects of interventions for MF in all stages of the disease.
SEARCH METHODS
We updated our searches of the following databases to May 2019: the Cochrane Skin Specialised Register, CENTRAL, MEDLINE, Embase, and LILACS. We searched 2 trials registries for additional references. For adverse event outcomes, we undertook separate searches in MEDLINE in April, July and November 2017.
SELECTION CRITERIA
Randomised controlled trials (RCTs) of local or systemic interventions for MF in adults with any stage of the disease compared with either another local or systemic intervention or with placebo.
DATA COLLECTION AND ANALYSIS
We used standard methodological procedures expected by Cochrane. The primary outcomes were improvement in health-related quality of life as defined by participants, and common adverse effects of the treatments. Key secondary outcomes were complete response (CR), defined as complete disappearance of all clinical evidence of disease, and objective response rate (ORR), defined as proportion of patients with a partial or complete response. We used GRADE to assess the certainty of evidence and considered comparisons of psoralen plus ultraviolet A (PUVA) light treatment as most important because this is first-line treatment for MF in most guidelines.
MAIN RESULTS
This review includes 20 RCTs (1369 participants) covering a wide range of interventions. The following were assessed as either treatments or comparators: imiquimod, peldesine, hypericin, mechlorethamine, nitrogen mustard and intralesional injections of interferon-α (IFN-α) (topical applications); PUVA, extracorporeal photopheresis (ECP: photochemotherapy), and visible light (light applications); acitretin, bexarotene, lenalidomide, methotrexate and vorinostat (oral agents); brentuximab vedotin; denileukin diftitox; mogamulizumab; chemotherapy with cyclophosphamide, doxorubicin, etoposide, and vincristine; a combination of chemotherapy with electron beam radiation; subcutaneous injection of IFN-α; and intramuscular injections of active transfer factor (parenteral systemics). Thirteen trials used an active comparator, five were placebo-controlled, and two compared an active operator to observation only. In 14 trials, participants had MF in clinical stages IA to IIB. All participants were treated in secondary and tertiary care settings, mainly in Europe, North America or Australia. Trials recruited both men and women, with more male participants overall. Trial duration varied from four weeks to 12 months, with one longer-term study lasting more than six years. We judged 16 trials as at high risk of bias in at least one domain, most commonly performance bias (blinding of participants and investigators), attrition bias and reporting bias. None of our key comparisons measured quality of life, and the two studies that did presented no usable data. Eighteen studies reported common adverse effects of the treatments. Adverse effects ranged from mild symptoms to lethal complications depending upon the treatment type. More aggressive treatments like systemic chemotherapy generally resulted in more severe adverse effects. In the included studies, CR rates ranged from 0% to 83% (median 31%), and ORR ranged from 0% to 88% (median 47%). Five trials assessed PUVA treatment, alone or combined, summarised below. There may be little to no difference between intralesional IFN-α and PUVA compared with PUVA alone for 24 to 52 weeks in CR (risk ratio (RR) 1.07, 95% confidence interval (CI) 0.87 to 1.31; 2 trials; 122 participants; low-certainty evidence). Common adverse events and ORR were not measured. One small cross-over trial found once-monthly ECP for six months may be less effective than twice-weekly PUVA for three months, reporting CR in two of eight participants and ORR in six of eight participants after PUVA, compared with no CR or ORR after ECP (very low-certainty evidence). Some participants reported mild nausea after PUVA but no numerical data were given. One participant in the ECP group withdrew due to hypotension. However, we are unsure of the results due to very low-certainty evidence. One trial comparing bexarotene plus PUVA versus PUVA alone for up to 16 weeks reported one case of photosensitivity in the bexarotene plus PUVA group compared to none in the PUVA-alone group (87 participants; low-certainty evidence). There may be little to no difference between bexarotene plus PUVA and PUVA alone in CR (RR 1.41, 95% CI 0.71 to 2.80) and ORR (RR 0.94, 95% CI 0.61 to 1.44) (93 participants; low-certainty evidence). One trial comparing subcutaneous IFN-α injections combined with either acitretin or PUVA for up to 48 weeks or until CR indicated there may be little to no difference in the common IFN-α adverse effect of flu-like symptoms (RR 1.32, 95% CI 0.92 to 1.88; 82 participants). There may be lower CR with IFN-α and acitretin compared with IFN-α and PUVA (RR 0.54, 95% CI 0.35 to 0.84; 82 participants) (both outcomes: low-certainty evidence). This trial did not measure ORR. One trial comparing PUVA maintenance treatment to no maintenance treatment, in participants who had already had CR, did report common adverse effects. However, the distribution was not evaluable. CR and OR were not assessable. The range of treatment options meant that rare adverse effects consequently occurred in a variety of organs.
AUTHORS' CONCLUSIONS
There is a lack of high-certainty evidence to support decision making in the treatment of MF. Because of substantial heterogeneity in design, missing data, small sample sizes, and low methodological quality, the comparative safety and efficacy of these interventions cannot be reliably established on the basis of the included RCTs. PUVA is commonly recommended as first-line treatment for MF, and we did not find evidence to challenge this recommendation. There was an absence of evidence to support the use of intralesional IFN-α or bexarotene in people receiving PUVA and an absence of evidence to support the use of acitretin or ECP for treating MF. Future trials should compare the safety and efficacy of treatments to PUVA, as the current standard of care, and should measure quality of life and common adverse effects.
Topics: Acitretin; Antineoplastic Agents; Bexarotene; Combined Modality Therapy; Humans; Immunologic Factors; Interferon-alpha; Mycosis Fungoides; Neoplasm Staging; PUVA Therapy; Photochemotherapy; Photopheresis; Randomized Controlled Trials as Topic; Skin Neoplasms
PubMed: 32632956
DOI: 10.1002/14651858.CD008946.pub3 -
Nutrients Apr 2024This review aims to evaluate the efficacy of any vitamin administration(s) in preventing and managing COVID-19 and/or long-COVID. Databases were searched up to May 2023... (Meta-Analysis)
Meta-Analysis Review
The Efficacy of Multivitamin, Vitamin A, Vitamin B, Vitamin C, and Vitamin D Supplements in the Prevention and Management of COVID-19 and Long-COVID: An Updated Systematic Review and Meta-Analysis of Randomized Clinical Trials.
This review aims to evaluate the efficacy of any vitamin administration(s) in preventing and managing COVID-19 and/or long-COVID. Databases were searched up to May 2023 to identify randomized clinical trials comparing data on the effects of vitamin supplementation(s) versus placebo or standard of care on the two conditions of interest. Inverse-variance random-effects meta-analyses were conducted to estimate pooled risk ratios (RRs) and 95% confidence intervals (CIs) for all-cause mortality between supplemented and non-supplemented individuals. Overall, 37 articles were included: two regarded COVID-19 and long-COVID prevention and 35 records the COVID-19 management. The effects of vitamin D in preventing COVID-19 and long-COVID were contrasting. Similarly, no conclusion could be drawn on the efficacy of multivitamins, vitamin A, and vitamin B in COVID-19 management. A few positive findings were reported in some vitamin C trials but results were inconsistent in most outcomes, excluding all-cause mortality (RR = 0.84; 95% CI: 0.72-0.97). Vitamin D results were mixed in most aspects, including mortality, in which benefits were observed in regular administrations only (RR = 0.67; 95% CI: 0.49-0.91). Despite some benefits, results were mostly contradictory. Variety in recruitment and treatment protocols might explain this heterogeneity. Better-designed studies are needed to clarify these vitamins' potential effects against SARS-CoV-2.
Topics: Humans; Dietary Supplements; COVID-19; Vitamins; Vitamin D; Randomized Controlled Trials as Topic; Ascorbic Acid; SARS-CoV-2; Vitamin A; COVID-19 Drug Treatment; Vitamin B Complex
PubMed: 38732592
DOI: 10.3390/nu16091345 -
BMC Geriatrics Mar 2023Given their potent antioxidation properties, carotenoids play a role in delaying and preventing dementia and mild cognitive impairment (MCI). However, observational... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Given their potent antioxidation properties, carotenoids play a role in delaying and preventing dementia and mild cognitive impairment (MCI). However, observational studies have found inconsistent results regarding the associations between blood carotenoid levels and the risk of dementia and MCI. We conducted this systematic review and meta-analysis to investigate the relationship between blood carotenoid levels and the risk of dementia and MCI.
METHODS
A systematic search was performed in the Web of Science, PubMed, Embase, and Cochrane Library electronic databases to retrieve relevant English articles published from their inception until February 23, 2023. Study quality was assessed by the Newcastle-Ottawa scale. Standardized mean differences (SMDs) and 95% confidence intervals (CIs) were pooled using random-effect meta-analyses. Ultimately, 23 studies (n = 6610) involving 1422 patients with dementia, 435 patients with MCI, and 4753 controls were included.
RESULTS
Our meta-analysis showed that patients with dementia had lower blood lycopene (SMD: -0.521; 95%CI: -0.741, -0.301), α-carotene (SMD: -0.489; 95%CI: -0.697, -0.281), β-carotene (SMD: -0.476; 95%CI: -0.784, -0.168), lutein (SMD: -0.516; 95%CI: -0.753, -0.279), zeaxanthin (SMD: -0.571; 95%CI: -0.910, -0.232) and β-cryptoxanthin (SMD: -0.617; 95%CI: -0.953, -0.281) than the controls. Our results indicated that blood carotenoid levels were significantly lower in patients with dementia than in controls, despite high heterogeneity across the studies. Owing to insufficient data, we did not observe a similar and stable relationship between blood carotenoid levels and MCI.
CONCLUSIONS
Our meta-analysis indicated that lower blood carotenoid levels may be a risk factor for dementia and MCI.
Topics: Humans; Cognitive Dysfunction; Carotenoids; beta Carotene; Lutein; Dementia
PubMed: 36997905
DOI: 10.1186/s12877-023-03900-7 -
Nutrition Reviews Feb 2021Worldwide, there is an array of clinical trials under way to evaluate treatment options against coronavirus disease 2019 (COVID-19), caused by the severe acute...
Worldwide, there is an array of clinical trials under way to evaluate treatment options against coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2. Concurrently, several nutritional therapies and alternative supportive treatments are also being used and tested to reduce the mortality associated with acute respiratory distress in patients with COVID-19. In the context of COVID-19, improved nutrition that includes micronutrient supplementation to augment the immune system has been recognized as a viable approach to both prevent and alleviate the severity of the infection. The potential role of micronutrients as immune-boosting agents is particularly relevant for low- and middle-income countries, which already have an existing high burden of undernutrition and micronutrient deficiencies. A systematic literature review was performed to identify nutritional interventions that might prevent or aid in the recovery from COVID-19. The PubMed, ScienceDirect, Cochrane, Scopus, Web of Science, and Google Scholar databases were searched electronically from February to April 2020. All abstracts and full-text articles were examined for their relevance to this review. The information gathered was collated under various categories. Deficiencies of micronutrients, especially vitamins A, B complex, C, and D, zinc, iron, and selenium, are common among vulnerable populations in general and among COVID-19 patients in particular and could plausibly increase the risk of mortality. Judicious use of need-based micronutrient supplementation, alongside existing micronutrient fortification programs, is warranted in the current global pandemic, especially in low- and middle-income economies.
Topics: COVID-19; Diet; Dietary Supplements; Humans; Immune System; Iron; Micronutrients; Nutrition Therapy; Nutritional Status; Selenium; Trace Elements; Vitamin A; Zinc
PubMed: 33570583
DOI: 10.1093/nutrit/nuaa063 -
Journal of Nutritional Science 2021Countries are increasingly transitioning from event-based vitamin A supplementation (VAS) distribution to delivery through routine health system contacts, shifting also... (Review)
Review
Countries are increasingly transitioning from event-based vitamin A supplementation (VAS) distribution to delivery through routine health system contacts, shifting also to administrative, electronic-based monitoring tools, a process that brings certain limitations affecting the quality of administrative VAS coverage. At present, there is no standardised methodology for measuring the coverage of VAS delivered through routine health services. To address this gap, we conducted a systematic review of the literature to identify and recommend methods to measure VAS coverage, with the aim of providing guidance to countries on the collection of consistent data for planning, monitoring and evaluating VAS programmes integrated into routine health systems. We searched the PubMed®, Embase®, Scopus, Google Scholar and World Health Organization (WHO) Global Index Medicus databases for studies published from 1 January 2000 to 1 January 2021, reporting original data on VAS coverage and methodologies used for measurement. We screened 2371 original titles and abstracts, assessed twenty-seven full-text articles and ultimately included eighteen studies. All but two studies used a coverage cluster survey (CCS) design to measure VAS coverage, adapting the WHO Vaccination Coverage Cluster Surveys methodology, by modifying sample size and sampling parameters. Annual two-dose VAS coverage was reported from only four studies. Until electronic-based systems to collect and analyse VAS data are equipped to measure routine two-dose VAS coverage using administrative data, CCSs that comply with the 2018 WHO Vaccination Coverage Cluster Surveys Reference Manual represent the gold-standard method for effective VAS programme monitoring.
Topics: Dietary Supplements; Humans; Surveys and Questionnaires; Vitamin A; Vitamin A Deficiency
PubMed: 34527226
DOI: 10.1017/jns.2021.65 -
Nutrients Nov 2023Adults with Crohn's disease (CD) may be at risk of micronutrient insufficiency in clinical remission through restrictive eating, malabsorption, abnormal losses or... (Review)
Review
Adults with Crohn's disease (CD) may be at risk of micronutrient insufficiency in clinical remission through restrictive eating, malabsorption, abnormal losses or inflammation. This systematic review synthesises the literature on micronutrient insufficiency in CD in clinical remission in terms of the prevalence of low circulating micronutrient concentrations and as a comparison against a healthy control (HC). Studies were included if the population was predominantly in remission. A total of 42 studies met the inclusion criteria; 12 were rated as low quality, leaving 30 studies covering 21 micronutrients of medium/high quality that were included in the synthesis. Vitamins D and B12 were the most frequently reported nutrients (8 and 11); there were few eligible studies for the remaining micronutrients. The prevalence studies were consistent in reporting individuals with low Vitamins A, B6, B12 and C, β-carotene, D, Magnesium, Selenium and Zinc. The comparator studies were inconsistent in finding differences with CD populations; Vitamin D, the most reported nutrient, was only lower than the HC in one-quarter of the studies. Adult CD populations are likely to contain individuals with low levels of one or more micronutrients, with the most substantial evidence for Vitamins D and B12. The studies on other micronutrients are of insufficient number, standardisation and quality to inform practice.
Topics: Adult; Humans; Micronutrients; Crohn Disease; Trace Elements; Vitamins; Vitamin A; Cholecalciferol
PubMed: 38004171
DOI: 10.3390/nu15224777 -
Advances in Nutrition (Bethesda, Md.) Oct 2022The aim of the current review was to explore the association between various dietary antioxidants and the risk of developing Parkinson's disease (PD). PubMed, Scopus,... (Meta-Analysis)
Meta-Analysis Review
The aim of the current review was to explore the association between various dietary antioxidants and the risk of developing Parkinson's disease (PD). PubMed, Scopus, Web of Science, and Google Scholar were searched up to March 2021. Prospective, observational cohort studies, nested case-control, and case-control designs that investigated the association between antioxidants and PD risk were included. A random-effects model was used to pool the RRs. The certainty of the evidence was rated using the GRADE (Grading of Recommendations Assessment, Development, and Evaluations) scoring system. In addition, a dose-response relation was examined between antioxidant intake and PD risk. Six prospective cohort studies and 2 nested case-control (total n = 448,737 with 4654 cases), as well as 6 case-control (1948 controls, 1273 cases) studies were eligible. The pooled RR was significantly lower for the highest compared with the lowest intake categories of vitamin E (n = 7; 0.84; 95% CI: 0.71, 0.99) and anthocyanins (n = 2; 0.76; 95% CI: 0.61, 0.96) in cohort studies. Conversely, a significantly higher risk of PD was observed for higher lutein intake (n = 3; 1.86; 95% CI: 1.20, 2.88) among case-control studies. Dose-response meta-analyses indicated a significant association between a 50-mg/d increase in vitamin C (n = 6; RR: 0.94; 95% CI: 0.88, 0.99), a 5-mg/d increment in vitamin E (n = 7; RR: 0.84; 95% CI: 0.70, 0.99), a 2-mg/d increment in β-carotene (n = 6; RR: 0.94, 95% CI: 0.89, 0.99), and a 1-mg/d increment in zinc (n = 1; OR: 0.65; 95% CI: 0.49, 0.86) and a reduced risk of PD. Overall, higher intake of antioxidant-rich foods may be associated with a lower risk of PD. Future well-designed prospective studies are needed to validate the present findings. The protocol was registered in the International Prospective Register of Systematic Reviews (PROSPERO) database (https://www.crd.york.ac.uk/PROSPERO, CRD42021242511).
Topics: Humans; Anthocyanins; Antioxidants; Ascorbic Acid; beta Carotene; Lutein; Parkinson Disease; Prospective Studies; Risk Factors; Vitamin E; Zinc; Observational Studies as Topic
PubMed: 35030236
DOI: 10.1093/advances/nmac001 -
Marine Drugs Apr 2022Fucoxanthin, belonging to the xanthophyll class of carotenoids, is a natural antioxidant pigment of marine algae, including brown macroalgae and diatoms. It represents... (Review)
Review
Fucoxanthin, belonging to the xanthophyll class of carotenoids, is a natural antioxidant pigment of marine algae, including brown macroalgae and diatoms. It represents 10% of the total carotenoids in nature. The plethora of scientific evidence supports the potential benefits of nutraceutical and pharmaceutical uses of fucoxanthin for boosting human health and disease management. Due to its unique chemical structure and action as a single compound with multi-targets of health effects, it has attracted mounting attention from the scientific community, resulting in an escalated number of scientific publications from January 2017 to February 2022. Fucoxanthin has remained the most popular option for anti-cancer and anti-tumor activity, followed by protection against inflammatory, oxidative stress-related, nervous system, obesity, hepatic, diabetic, kidney, cardiac, skin, respiratory and microbial diseases, in a variety of model systems. Despite much pharmacological evidence from in vitro and in vivo findings, fucoxanthin in clinical research is still not satisfactory, because only one clinical study on obesity management was reported in the last five years. Additionally, pharmacokinetics, safety, toxicity, functional stability, and clinical perspective of fucoxanthin are substantially addressed. Nevertheless, fucoxanthin and its derivatives are shown to be safe, non-toxic, and readily available upon administration. This review will provide pharmacological insights into fucoxanthin, underlying the diverse molecular mechanisms of health benefits. However, it requires more activity-oriented translational research in humans before it can be used as a multi-target drug.
Topics: Carotenoids; Humans; Neoplasms; Seaweed; Xanthophylls
PubMed: 35621930
DOI: 10.3390/md20050279