Longitudinal study of the scalp microbiome suggests coconut oil to enrich healthy scalp commensals.
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ABSTRACT:
SUBMITTER: Saxena R
PROVIDER: S-EPMC8012655 | biostudies-literature |
REPOSITORIES: biostudies-literature
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Project description:Several scalp microbiome studies from different populations have revealed the association of dandruff with bacterial and fungal dysbiosis. However, the functional role of scalp microbiota in scalp disorders and health remains scarcely explored. Here, we examined the bacterial and fungal diversity of the scalp microbiome and their potential functional role in the healthy and dandruff scalp of 140 Indian women. Propionibacterium acnes and Staphylococcus epidermidis emerged as the core bacterial species, where the former was associated with a healthy scalp and the latter with dandruff scalp. Along with the commonly occurring Malassezia species (M. restricta and M. globosa) on the scalp, a strikingly high association of dandruff with yet uncharacterized Malassezia species was observed in the core mycobiome. Functional analysis showed that the fungal microbiome was enriched in pathways majorly implicated in cell-host adhesion in the dandruff scalp, while the bacterial microbiome showed a conspicuous enrichment of pathways related to the synthesis and metabolism of amino acids, biotin, and other B-vitamins, which are reported as essential nutrients for hair growth. A systematic measurement of scalp clinical and physiological parameters was also carried out, which showed significant correlations with the microbiome and their associated functional pathways. The results point toward a new potential role of bacterial commensals in maintaining the scalp nutrient homoeostasis and highlights an important and yet unknown role of the scalp microbiome, similar to the gut microbiome. This study, therefore, provides new perspectives on the better understanding of the pathophysiology of dandruff.
| S-EPMC6180232 | biostudies-literature
Project description:High dietary saturated fat intake is associated with higher blood concentrations of low-density lipoprotein cholesterol (LDL-C), an established risk factor for coronary heart disease. However, there is increasing interest in whether various dietary oils or fats with different fatty acid profiles such as extra virgin coconut oil may have different metabolic effects but trials have reported inconsistent results. We aimed to compare changes in blood lipid profile, weight, fat distribution and metabolic markers after four weeks consumption of 50?g daily of one of three different dietary fats, extra virgin coconut oil, butter or extra virgin olive oil, in healthy men and women in the general population.Randomised clinical trial conducted over June and July 2017.General community in Cambridgeshire, UK.Volunteer adults were recruited by the British Broadcasting Corporation through their websites. Eligibility criteria were men and women aged 50-75 years, with no known history of cancer, cardiovascular disease or diabetes, not on lipid lowering medication, no contraindications to a high-fat diet and willingness to be randomised to consume one of the three dietary fats for 4?weeks. Of 160 individuals initially expressing an interest and assessed for eligibility, 96 were randomised to one of three interventions; 2 individuals subsequently withdrew and 94 men and women attended a baseline assessment. Their mean age was 60 years, 67% were women and 98% were European Caucasian. Of these, 91 men and women attended a follow-up assessment 4?weeks later.Participants were randomised to extra virgin coconut oil, extra virgin olive oil or unsalted butter and asked to consume 50?g daily of one of these fats for 4?weeks, which they could incorporate into their usual diet or consume as a supplement.The primary outcome was change in serum LDL-C; secondary outcomes were change in total and high-density lipoprotein cholesterol (TC and HDL-C), TC/HDL-C ratio and non-HDL-C; change in weight, body mass index (BMI), waist circumference, per cent body fat, systolic and diastolic blood pressure, fasting plasma glucose and C reactive protein.LDL-C concentrations were significantly increased on butter compared with coconut oil (+0.42, 95%?CI 0.19 to 0.65 mmol/L, P<0.0001) and with olive oil (+0.38, 95%?CI 0.16 to 0.60?mmol/L, P<0.0001), with no differences in change of LDL-C in coconut oil compared with olive oil (-0.04, 95%?CI -0.27 to 0.19?mmol/L, P=0.74). Coconut oil significantly increased HDL-C compared with butter (+0.18, 95%?CI 0.06 to 0.30?mmol/L) or olive oil (+0.16, 95%?CI 0.03 to 0.28?mmol/L). Butter significantly increased TC/HDL-C ratio and non-HDL-C compared with coconut oil but coconut oil did not significantly differ from olive oil for TC/HDL-C and non-HDL-C. There were no significant differences in changes in weight, BMI, central adiposity, fasting blood glucose, systolic or diastolic blood pressure among any of the three intervention groups.Two different dietary fats (butter and coconut oil) which are predominantly saturated fats, appear to have different effects on blood lipids compared with olive oil, a predominantly monounsaturated fat with coconut oil more comparable to olive oil with respect to LDL-C. The effects of different dietary fats on lipid profiles, metabolic markers and health outcomes may vary not just according to the general classification of their main component fatty acids as saturated or unsaturated but possibly according to different profiles in individual fatty acids, processing methods as well as the foods in which they are consumed or dietary patterns. These findings do not alter current dietary recommendations to reduce saturated fat intake in general but highlight the need for further elucidation of the more nuanced relationships between different dietary fats and health.NCT03105947; Results.
| S-EPMC5855206 | biostudies-other
Project description:Introduction: Medium-chain-triglycerides (MCT), formed by fatty acids with a length of 6-12 carbon atoms (C6-C12), constitute about two thirds of coconut oil (Coc). MCT have specific metabolic properties which has led them to be described as ketogenic even in the absence of carbohydrate restriction. This effect has mainly been demonstrated for caprylic acid (C8), which constitutes about 6-8% of coconut oil. Our aim was to quantify ketosis and blood glucose after intake of Coc and C8, with and without glucose intake. Sunflower oil (Suf) was used as control, expected to not break fasting ketosis, nor induce supply-driven ketosis. Method: In a 6-arm cross-over design, 15 healthy volunteers-age 65-73, 53% women-were tested once a week. After a 12-h fast, ketones were measured during 4 h after intake of coffee with cream, in combination with each of the intervention arms in a randomized order: 1. Suf (30 g); 2. C8 (20 g) + Suf (10 g); 3. C8 (20 g) + Suf (10 g) + Glucose (50 g); 4. Coc (30 g); 5. Coc (30 g) + Glucose (50 g); 6. C8 (20 g) + Coc (30 g). The primary outcome was absolute blood levels of the ketone ?-hydroxybutyrate, area under the curve (AUC). ANOVA for repeated measures was performed to compare arms. Results: ?-hydroxybutyrate, AUC/time (mean ± SD), for arms were 1: 0.18 ± 0.11; 2: 0.45 ± 0.19; 3: 0.28 ± 0.12; 4: 0.22 ± 0.12; 5: 0.08 ± 0.04; 6: 0.45 ± 0.20 (mmol/L). Differences were significant (all p ? 0.02), except for arm 2 vs. 6, and 4 vs. 1 & 3. Blood glucose was stable in arm 1, 2, 4, & 6, at levels slightly below baseline (p ? 0.05) at all timepoints hours 1-4 after intake. Conclusions: C8 had a higher ketogenic effect than the other components. Coc was not significantly different from Suf, or C8 with glucose. In addition, we report that a 16-h non-carbohydrate window contributed to a mild ketosis, while blood glucose remained stable. Our results suggest that time-restricted feeding regarding carbohydrates may optimize ketosis from intake of MCT. Clinical Trial Registration: The study was registered as a clinical trial on ClinicalTrials.gov, NCT03904433.
| S-EPMC7175812 | biostudies-literature
Project description:Background: Ketones are the brain's main alternative fuel to glucose. Dietary medium-chain triglyceride (MCT) supplements increase plasma ketones, but their ketogenic efficacy relative to coconut oil (CO) is not clear. Objective: The aim was to compare the acute ketogenic effects of the following test oils in healthy adults: coconut oil [CO; 3% tricaprylin (C8), 5% tricaprin (C10)], classical MCT oil (C8-C10; 55% C8, 35% C10), C8 (>95% C8), C10 (>95% C10), or CO mixed 50:50 with C8-C10 or C8. Methods: In a crossover design, 9 participants with mean ± SD ages 34 ± 12 y received two 20-mL doses of the test oils prepared as an emulsion in 250 mL lactose-free skim milk. During the control (CTL) test, participants received only the milk vehicle. The first test dose was taken with breakfast and the second was taken at noon but without lunch. Blood was sampled every 30 min over 8 h for plasma acetoacetate and ?-hydroxybutyrate (?-HB) analysis. Results: C8 was the most ketogenic test oil with a day-long mean ± SEM of +295 ± 155 µmol/L above the CTL. C8 alone induced the highest plasma ketones expressed as the areas under the curve (AUCs) for 0-4 and 4-8 h (780 ± 426 µmol ? h/L and 1876 ± 772 µmol ? h/L, respectively); these values were 813% and 870% higher than CTL values (P < 0.01). CO plasma ketones peaked at +200 µmol/L, or 25% of the C8 ketone peak. The acetoacetate-to-?-HB ratio increased 56% more after CO than after C8 after both doses. Conclusions: In healthy adults, C8 alone had the highest net ketogenic effect over 8 h, but induced only half the increase in the acetoacetate-to-?-HB ratio compared with CO. Optimizing the type of MCT may help in developing ketogenic supplements designed to counteract deteriorating brain glucose uptake associated with aging. This trial was registered at clinicaltrials.gov as NCT 02679222.
| S-EPMC5998344 | biostudies-literature
Project description:The gene expression profile of blood drawn from healthy individuals was studied over a period of six months, at five time points. The gene expression profiles appeared to be constant over one month and to slightly vary over three months. A small proportion of genes were found to be differentially regulated according to gender. Differential gene regulation by age (in subjects 25–55 years of age versus subjects > 55 years of age) was not observed.
2009-05-09 | GSE16028 | GEO
Project description:The structure and function of infant skin is not fully developed until 34 weeks of gestation, and this immaturity is associated with risk of late-onset sepsis (LOS). Topical coconut oil improves preterm-infant skin integrity and may reduce LOS. However, data on early-life skin-microbiome succession and potential effects of emollient skin care in preterm infants are scarce. We therefore collected skin-microbiome samples from the ear, axilla, and groin on days 1, 7, 14, and 21 from preterm infants born <30 weeks of gestation as part of a randomized clinical trial of standard skin care vs. topical coconut oil. We found that within-sample microbiome diversity was highest on day 1 after birth, with a subsequent decline and emergence of Staphylococcus genus dominance from day 7. Moreover, microbiome assembly was less diverse in infants receiving coconut oil vs. standard skin care. Our study provides novel data on preterm-infant skin-microbiome composition and highlights the modifying potential of emollient skin care.
| S-EPMC10706365 | biostudies-literature
Project description:Fish oil, olive oil, and coconut oil dietary supplementation have several cardioprotective benefits, but it is not established if they can protect against air pollution-induced adverse effects. We hypothesized that these dietary supplements would attenuate ozone-induced systemic and pulmonary effects. Male Wistar Kyoto rats were fed either a normal diet, or a diet enriched with fish, olive, or coconut oil starting at 4 weeks of age for 8 weeks. Animals were then exposed to air or ozone (0.8 ppm), 4h/day for 2 consecutive days. The fish oil diet completely abolished phenylephrine-induced vasoconstriction that was increased following ozone exposure in the animals fed all other diets. Only the fish oil diet increased baseline levels of bronchoalveolar lavage fluid (BALF) markers of lung injury and inflammation. Ozone-induced pulmonary injury/inflammation were comparable in rats on normal, coconut oil, and olive oil diets with altered expression of markers in animals fed the fish oil diet. Fish oil, regardless of exposure, led to enlarged, foamy macrophages in the BALF that coincided with decreased mRNA expression of cholesterol transporters, cholesterol receptors, and nuclear receptors in the lung. Serum miRNA profile was assessed using small RNA-sequencing in normal and fish oil groups and demonstrated marked depletion of a variety of miRNAs, several of which were of splenic origin. No ozone-specific changes were noted. Collectively, these data indicate that while fish oil offered protection from ozone-induced aortic vasoconstriction, it increased pulmonary injury/inflammation and impaired lipid transport mechanisms resulting in foamy macrophage accumulation, demonstrating the need to be cognizant of potential off-target pulmonary effects that might offset the overall benefit of this vasoprotective dietary supplement.
2018-01-11 | GSE102015 | GEO
Project description:BackgroundDuring recent years several studies have investigated the impact of different dietary oils on body weight. They have shown differential positive and negative effects on anthropometry. We investigated the effects of palm and coconut oils on body weight and other anthropometric parameters, considering their importance as a primary source of saturated fat, controlling for other confounding variable such as total energy intake.MethodsThe study was conducted as a sequential feeding clinical trial with 40 healthy men and women divided into two feeding periods of initial palm oil (8 weeks) and subsequent coconut oil (8 weeks), with a 16-week washout period in between. Each participant received a pre-determined volume of each oil, which were integrated into their routine main meals and snacks during the respective study periods. Changes in body weight, body mass index (BMI), waist circumference (WC), hip circumference (HC), and waist-to-hip ratio (WHR) were evaluated. Physical activity levels and dietary intake were also evaluated as potential confounding factors.ResultsThirty-seven participants completed both oil treatment periods. The mean (± SD) age of the participants was 39 (± 13.1) years. There were no significant differences in any of the anthropometric parameters between the initial point of feeding coconut oil and the initial point of feeding palm oil. Following both oil treatment phases, no significant changes in the subjects' body weight, BMI, or other anthropometric measurements (WC, HC, and WHR) were observed.ConclusionNeither coconut oil nor palm oil significantly changed anthropometry-related cardiovascular risk factors such as body weight, BMI, WC, HC, and WHR.Trial registrationSri Lankan Clinical Trial Registry: SLCTR/2019/034 on 4th October 2019 ( https://slctr.lk/trials/slctr-2019-034 ).
| S-EPMC10782760 | biostudies-literature
Project description:ObjectiveTo determine if routine electroencephalography (EEG) in seizure-naive infants with tuberous sclerosis complex (TSC) can predict epilepsy and subsequent neurocognitive outcomes.MethodsForty infants 7 months of age or younger and meeting the genetic or clinical diagnostic criteria for tuberous sclerosis were enrolled. Exclusion criteria included prior history of seizures or treatment with antiseizure medications. At each visit, seizure history and 1-hour awake and asleep video-EEG, standardized across all sites, were obtained until 2 years of age. Developmental assessments (Mullen and Vineland-II) were completed at 6, 12, and 24 months of age.ResultsOf 40 infants enrolled (mean age of 82.4 days), 32 completed the study. Two were lost to follow-up and six were treated with antiepileptic drugs (AEDs) due to electrographic seizures and/or interictal epileptiform discharges (IEDs) on their EEG studies prior to the onset of clinical seizures. Seventeen of the 32 remaining children developed epilepsy at a mean age of 7.5 months (standard deviation [SD] = 4.4). Generalized/focal slowing, hypsarrhythmia, and generalized/focal attenuation were not predictive for the development of clinical seizures. Presence of IEDs had a 77.3% positive predictive value and absence a 70% negative predictive value for developing seizures by 2 years of age. IEDs preceded clinical seizure onset by 3.6 months (mean). Developmental testing showed significant decline, only in infants with ongoing seizures, but not infants who never developed seizures or whose seizures came under control.SignificanceIEDs identify impending epilepsy in the majority (77%) of seizure-naive infants with TSC. The use of a 1-hour awake and asleep EEG can be used as a biomarker for ongoing epileptogenesis in most, but not all, infants with TSC. Persistent seizures, but not history of interictal epileptiform activity or history of well-controlled seizures, correlated with low scores on the Vineland and Mullen tests at 2 years of age.
| S-EPMC6910957 | biostudies-literature
Project description:Refinement is usually used to remove undesired components to improve coconut oil quality. In the present study, crude coconut oil (CCO) was refined in four stages: conventional degumming, neutralization, bleaching, and deodorization. Physiochemical indices during the refinement were evaluated: peroxide value (PV), free fatty acid (FFA), fatty acid composition; fat composition; triacylglycerol profile, micronutrient (e.g., tocopherols and sterols) and contaminant (e.g., 3-monochloropropane-1,2-diol esters (3-MCPD esters), and glycidyl esters (GEs) levels. Compared to CCO, the quality of refined oil was improved by reducing PV and FFA levels. No significant changes in triacylglycerol compositions were found during refinement. However, unsaturated fatty acids like oleic and linoleic acids were decreased after refinement. Also, some micronutrients like tocopherol and sterol were decreased from 12.39 to 0.10 mg/kg and from 679.69 to 426.50 mg/kg, respectively. The undesired contaminants, i.e., 3-MCPD esters and GEs, increased markedly during refinement.
| S-EPMC6542917 | biostudies-literature