The relative abundance of fecal bacterial species belonging to the Firmicutes and Bacteroidetes phyla is related to plasma levels of bile acids in young adults.

BACKGROUND: Gut bacteria play a crucial role in the metabolism of bile acids (BA). Whether an association exists between the fecal microbiota composition and circulating BA levels in humans is poorly understood. Here, we investigated the relationship between fecal microbiota diversity and composition with plasma levels of BA in young adults. METHODS: Fecal microbiota diversity/composition was analyzed with 16S rRNA sequencing in 80 young adults (74% women; 21.9 ± 2.2 years old). Plasma levels of BA were measured using liquid chromatography-tandem mass spectrometry. PERMANOVA and Spearman correlation analyses were used to investigate the association between fecal microbiota parameters and plasma levels of BA. RESULTS: Fecal microbiota beta (P = 0.025) and alpha diversity indexes of evenness (rho = 0.237, P = 0.033), Shannon (rho = 0.313, P = 0.004), and inverse Simpson (rho = 0.283, P = 0.010) were positively associated with plasma levels of the secondary BA glycolithocholic acid (GLCA). The relative abundance of genera belonging to the Firmicutes and Bacteroidetes phyla was positively correlated with plasma levels of GLCA (all rho ≥ 0.225, P ≤ 0.049). However, the relative abundance of species from Firmicutes and Bacteroidetes phyla were negatively correlated with plasma levels of primary and secondary BA (all rho ≤ - 0.220, P ≤ 0.045), except for the relative abundance of Bacteroides vulgatus, Alistipes onderdonkii, and Bacteroides xylanisolvens species (Bacteroidetes phylum) that were positively correlated with the plasma levels of GLCA. CONCLUSIONS: The relative abundance of specific fecal bacteria species is associated with plasma levels of BA in young adults. However, further investigations are required to validate whether the composition of the gut microbiota can regulate the plasma concentrations of BA in humans.

Longitudinal associations between cardiovascular biomarkers and metabolic syndrome during puberty: the PUBMEP study.

Puberty has been described as a life stage of considerable metabolic risk specially for those with obesity. The low-grade systemic inflammatory status associated with obesity could be one of the connections with metabolic syndrome (MetS). Thus, we aimed to assess the relationship between inflammatory and cardiovascular biomarkers and the development of MetS during puberty. Seventy-five children from the PUBMEP study (33 females), aged 4-18 years, were included. Cardiovascular and inflammatory biomarkers were measured in the prepubertal and pubertal stage, including high-sensitivity C-reactive protein (CRP), leptin, tumor necrosis factor-alpha (TNFα), interleukin 8 (IL8), monocyte chemoattractant protein 1 (MCP-1), total plasminogen activator inhibitor-1 (tPAI), resistin, adiponectin, myeloperoxidase (MPO), and soluble intercellular adhesion molecule-1 (sICAM-1). MetS was diagnosed at each measurement point. Mixed-effects and logistic regressions were performed. Those children with MetS in puberty presented higher prepubertal values of several cardiometabolic biomarkers in comparison to those without MetS (z-score body mass index (zBMI), waist circumference, insulin, HOMA-IR, leptin, and tPAI (p < 0.05)). For prepubertal children with obesity, the odds of developing MetS in puberty were significantly higher in those having high zBMI (OR = 4.27; CI: 1.39-22.59) or high concentrations of tPAI (OR = 1.19; CI: 1.06-1.43). CONCLUSION: Those with obesity with higher prepubertal tPAI plasma levels had 19% higher odds of having MetS at puberty highlighting the existence of association between MetS, obesity, and inflammation already in puberty. Thus, assessing cardiometabolic and inflammatory status in children with obesity already at prepuberty is key to avoiding future comorbidities. WHAT IS KNOWN: • Inflammation, metabolic syndrome, and obesity may have their onset in childhood. • Puberty is a life stage characterized for an increased cardiovascular risk. WHAT IS NEW: • Prepuberty state could be an early indicator of future cardiometabolic risk. • Children with obesity and high total plasminogen have higher odds of future metabolic syndrome.

Effects of a Novel Infant Formula on the Fecal Microbiota in the First Six Months of Life: The INNOVA 2020 Study.

Exclusive breastfeeding is highly recommended for infants for at least the first six months of life. However, for some mothers, it may be difficult or even impossible to do so. This can lead to disturbances in the gut microbiota, which in turn may be related to a higher incidence of acute infectious diseases. Here, we aimed to evaluate whether a novel starting formula versus a standard formula provides a gut microbiota composition more similar to that of breastfed infants in the first 6 months of life. Two hundred and ten infants (70/group) were enrolled in the study and completed the intervention until 12 months of age. For the intervention period, infants were divided into three groups: Group 1 received formula 1 (INN) with a lower amount of protein, a proportion of casein to whey protein ratio of about 70/30 by increasing the content of α-lactalbumin, and with double the amount of docosahexaenoic acid/arachidonic acid than the standard formula; INN also contained a thermally inactivated postbiotic (Bifidobacterium animalis subsp. lactis). Group 2 received the standard formula (STD) and the third group was exclusively breastfed (BF) for exploratory analysis. During the study, visits were made at 21 days, 2, 4, and 6 months of age, with ±3 days for the visit at 21 days of age, ±1 week for the visit at 2 months, and ±2 weeks for the others. Here, we reveal how consuming the INN formula promotes a similar gut microbiota composition to those infants that were breastfed in terms of richness and diversity, genera, such as Bacteroides, Bifidobacterium, Clostridium, and Lactobacillus, and calprotectin and short-chain fatty acid levels at 21 days, 2 and 6 months. Furthermore, we observed that the major bacteria metabolic pathways were more alike between the INN formula and BF groups compared to the STD formula group. Therefore, we assume that consumption of the novel INN formula might improve gut microbiota composition, promoting a healthier intestinal microbiota more similar to that of an infant who receives exclusively human milk.

Innova 2020: A Follow-Up Study of the Fecal Microbiota of Infants Using a Novel Infant Formula between 6 Months and 12 Months of Age.

The World Health Organization recommends exclusive breastfeeding on demand until at least the sixth month of life. Breast milk or infant formula is the infant's primary food source until the age of one year, followed by the gradual introduction of other foods. During weaning, the intestinal microbiota evolves to a profile close to that of the adult, and its disruption can result in an increased incidence of acute infectious diseases. We aimed to determine whether a novel starting formula (INN) provides gut microbiota compositions more similar to those of breastfed (BF) infants from 6 to 12 months of age compared to a standard formula (STD). This study included 210 infants (70 per group) who completed the intervention until they reached the age of 12 months. In the intervention period, infants were divided into three groups. Group 1 received an INN formula with a lower protein content, a casein to whey protein ratio of approximately 70/30, twice as much docosahexaenoic acid as the STD formula, a thermally inactivated postbiotic (Bifidobacterium animalis subsp. lactis, BPL1TM HT), and twice as much arachidonic acid as the STD formula contained. The second group received the STD formula, while the third group was exclusively BF for exploratory purposes. In the course of the study, visits were conducted at 6 months and 12 months of age. Compared to the BF and STD groups, the Bacillota phylum levels in the INN group were significantly reduced after 6 months. At the end of 6 months, the alpha diversity indices of the BF and INN groups differed significantly from those of the STD group. At 12 months, the Verrucomicrobiota phylum levels in the STD group were significantly lower than those in the BF and INN groups. Based on the comparison between 6 and 12 months, the Bacteroidota phylum levels in the BF group were significantly higher than those in the INN and STD groups. When comparing the INN group with the BF and STD groups, Clostridium sensu stricto 1 was significantly higher in the INN group. The STD group had higher levels of calprotectin than the INN and BF groups at 6 months. The immunoglobulin A levels in the STD group were significantly lower than those in the INN and BF groups after 6 months. Both formulas had significantly higher levels of propionic acid than the BF group at 6 months. At 6 months, the STD group showed a higher quantification of all metabolic pathways than the BF group. The INN formula group exhibited similar behavior to the BF group, except for the superpathway of phospholipid biosynthesis (E. coli). We hypothesize that the novel INN formula may promote an intestinal microbiota that is more similar to the microbiota of an infant who consumes only human milk before the weaning period.

Impact of Physical Activity Intensity Levels on the Cardiometabolic Risk Status of Children: The Genobox Study.

Childhood obesity has been related to metabolic syndrome and low-grade chronic inflammation. This study aimed to evaluate the impact of physical activity intensities and practice on inflammation, endothelial damage, and cardiometabolic risk factors in children. There were 513 participants, aged 6-14 years, recruited for the study. Physical activity was measured by accelerometry, and the children were classified into four groups according to quartiles of moderate to vigorous physical activity (MVPA) practice as very low active, low active, moderate active, and high active. Anthropometric measures, blood pressure, and plasma metabolic and proinflammatory parameters were analyzed. Very low active group presented a worse lipid profile and higher insulin, leptin, adiponectin, resistin, matrix metallopeptidase-9, and tissue plasminogen activator inhibitor-1, while lower levels of tumor necrosis factor-alpha, Type 1 macrophages, and interleukin 8 than high-active children. Regression analyses showed that a higher MVPA practice was associated with lower levels of triacylglycerols (ß: -0.118; p = .008), resistin (ß: -0.151; p = .005), tPAI (ß: -0.105; p = .046), and P-selectin (ß: -0.160; p = .006), independently of sex, age, and body mass index (BMI). In contrast, a higher BMI was associated with higher levels of insulin (ß: 0.370; p < .001), Homeostasis Model Assessment (ß: 0.352; p < .001), triacylglycerols (ß: 0.209; p < .001), leptin (ß: 0.654; p < .001), tumor necrosis factor-alpha (ß: 0.182; p < .001), Type 1macrophages (ß: 0.181; p < .001), and tissue plasminogen activator inhibitor (ß: 0.240; p < .001), independently of sex, age, and MVPA. A better anthropometric, metabolic, and inflammatory profile was detected in the most active children; however, these differences were partly due to BMI. These results suggest that a higher MVPA practice and a lower BMI in children may lead to a better cardiometabolic status.

Vitamin D Deficiency and COVID-19: A Biological Database Study on Pathways and Gene-Disease Associations.

Vitamin D (VD) is a fat-soluble vitamin, and pivotal for maintaining health. Several genetic markers have been related to a deficient VD status; these markers could confer an increased risk to develop osteoporosis and other chronic diseases. A VD deficiency could also be a determinant of a severe COVID-19 disease. This study aimed to interrogate genetic/biological databases on the biological implications of a VD deficiency and its association with diseases, to further explore its link with COVID-19. The genetic variants of both a VD deficiency and COVID-19 were identified in the genome-wide association studies (GWAS) catalog and other sources. We conducted enrichment analyses (considering corrected p-values < 0.05 as statistically significant) of the pathways, and gene-disease associations using tools, such as FUMA, REVIGO, DAVID and DisGeNET, and databases, such as the Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO). There were 26 and 46 genes associated with a VD deficiency and COVID-19, respectively. However, there were no genes shared between the two. Genes related to a VD deficiency were involved in the metabolism of carbohydrates, retinol, drugs and xenobiotics, and were associated with the metabolic syndrome and related factors (obesity, hypertension and diabetes mellitus), as well as with neoplasms. There were few enriched pathways and disease connections for the COVID-19-related genes, among which some of the aforementioned comorbidities were also present. In conclusion, genetic factors that influence the VD levels in the body are most prominently associated with nutritional and metabolic diseases. A VD deficiency in high-risk populations could be therefore relevant in a severe COVID-19, underlining the need to examine whether a VD supplementation could reduce the severity of this disease.

Bifidobacterium longum subsp. infantis CECT 7210 Reduces Inflammatory Cytokine Secretion in Caco-2 Cells Cultured in the Presence of Escherichia coli CECT 515.

Previous works have described the activity of Bifidobacterium longum subsp. infantis CECT 7210 (also commercially named B. infantis IM-1®) against rotavirus in mice and intestinal pathogens in piglets, as well as its diarrhea-reducing effect on healthy term infants. In the present work, we focused on the intestinal immunomodulatory effects of B. infantis IM-1® and for this purpose we used the epithelial cell line isolated from colorectal adenocarcinoma Caco-2 and a co-culture system of human dendritic cells (DCs) from peripheral blood together with Caco-2 cells. Single Caco-2 cultures and Caco-2: DC co-cultures were incubated with B. infantis IM-1® or its supernatant either in the presence or absence of Escherichia coli CECT 515. The B. infantis IM-1® supernatant exerted a protective effect against the cytotoxicity caused by Escherichia coli CECT 515 on single cultures of Caco-2 cells as viability reached the values of untreated cells. B. infantis IM-1® and its supernatant also decreased the secretion of pro-inflammatory cytokines by Caco-2 cells and the co-cultures incubated in the presence of E. coli CECT 515, with the response being more modest in the latter, which suggests that DCs modulate the activity of Caco-2 cells. Overall, the results obtained point to the immunomodulatory activity of this probiotic strain, which might underlie its previously reported beneficial effects.

The Metabolic Impact of Two Different Parenteral Nutrition Lipid Emulsions in Children after Hematopoietic Stem Cell Transplantation: A Lipidomics Investigation.

Hematopoietic stem cell transplantation (HSCT) involves the infusion of either bone marrow or blood cells preceded by toxic chemotherapy. However, there is little knowledge about the clinical benefits of parenteral nutrition (PN) in patients receiving high-dose chemotherapy during HSCT. We investigated the lipidomic profile of plasma and the targeted fatty acid profiles of plasma and erythrocytes in children after HSCT using PN with either a fish oil-based lipid emulsion or a classic soybean oil emulsion. An untargeted liquid chromatography high-resolution mass spectrometry platform connected with a novel in silico annotation algorithm was utilized to determine the most relevant chemical subclasses affected. In addition, we explored the interrelation between the lipidomics profile in plasma, the targeted fatty acid profile in plasma and erythrocytes, several biomarkers of inflammation, and antioxidant defense using an innovative data integration analysis based on Latent Components. We observed that the fish oil-based lipid emulsion had an impact in several lipid subclasses, mainly glycerophosphocholines (PC), glycerophosphoserines (PS), glycerophosphoethanolamines (PE), oxidized PE (O-PE), 1-alkyl,2-acyl PS, lysophosphatidylethanolamines (LPE), oxidized PS (O-PS) and dicarboxylic acids. In contrast, the classic soybean oil emulsion did not. Several connections across the different blocks of data were found and aid in interpreting the impact of the lipid emulsions on metabolic health.

Elevated plasma succinate levels are linked to higher cardiovascular disease risk factors in young adults.

BACKGROUND: Succinate is produced by both host and microbiota, with a key role in the interplay of immunity and metabolism and an emerging role as a biomarker for inflammatory and metabolic disorders in middle-aged adults. The relationship between plasma succinate levels and cardiovascular disease (CVD) risk in young adults is unknown. METHODS: Cross-sectional study in 100 (65% women) individuals aged 18-25 years from the ACTIvating Brown Adipose Tissue through Exercise (ACTIBATE) study cohort. CVD risk factors, body composition, dietary intake, basal metabolic rate, and cardiorespiratory fitness were assessed by routine methods. Plasma succinate was measured with an enzyme-based assay. Brown adipose tissue (BAT) was evaluated by positron emission tomography, and circulating oxylipins were assessed by targeted metabolomics. Fecal microbiota composition was analyzed in a sub-sample. RESULTS: Individuals with higher succinate levels had higher levels of visceral adipose tissue (VAT) mass (+ 42.5%), triglycerides (+ 63.9%), C-reactive protein (+ 124.2%), diastolic blood pressure (+ 5.5%), and pro-inflammatory omega-6 oxylipins than individuals with lower succinate levels. Succinate levels were also higher in metabolically unhealthy individuals than in healthy overweight/obese peers. Succinate levels were not associated with BAT volume or activity or with fecal microbiota composition and diversity. CONCLUSIONS: Plasma succinate levels are linked to a specific pro-inflammatory omega-6 signature pattern and higher VAT levels, and seem to reflect the cardiovascular status of young adults.

Efficiency of Machine Learning Algorithms for the Determination of Macrovesicular Steatosis in Frozen Sections Stained with Sudan to Evaluate the Quality of the Graft in Liver Transplantation.

Liver transplantation is the only curative treatment option in patients diagnosed with end-stage liver disease. The low availability of organs demands an accurate selection procedure based on histological analysis, in order to evaluate the allograft. This assessment, traditionally carried out by a pathologist, is not exempt from subjectivity. In this sense, new tools based on machine learning and artificial vision are continuously being developed for the analysis of medical images of different typologies. Accordingly, in this work, we develop a computer vision-based application for the fast and automatic objective quantification of macrovesicular steatosis in histopathological liver section slides stained with Sudan stain. For this purpose, digital microscopy images were used to obtain thousands of feature vectors based on the RGB and CIE L*a*b* pixel values. These vectors, under a supervised process, were labelled as fat vacuole or non-fat vacuole, and a set of classifiers based on different algorithms were trained, accordingly. The results obtained showed an overall high accuracy for all classifiers (>0.99) with a sensitivity between 0.844 and 1, together with a specificity >0.99. In relation to their speed when classifying images, KNN and Naïve Bayes were substantially faster than other classification algorithms. Sudan stain is a convenient technique for evaluating ME in pre-transplant liver biopsies, providing reliable contrast and facilitating fast and accurate quantification through the machine learning algorithms tested.

Self-reported prevalence of periodontal disease among the Spanish population and immigrants: 2006, 2011/12 and 2017: a population-based study.

BACKGROUND: Periodontal disease is one of the most common pathologies in the population. Self-reporting has been used as a diagnostic tool in large populations, among other reasons, to detect the needs of potentially vulnerable groups. This study evaluated the prevalence of periodontal disease in people of Spanish nationality and immigrants in Spain. METHODS: This population-based, cross-sectional study was carried out using data obtained from National Health Interview Surveys (NHSs) carried out in 2006, 2011/2012 and 2017 in Spain. Subjects aged 16 years and older were included in the NHS-2006 and aged 15 years and older were included in the other NHSs. The following variables were self-reported by the participants: gum bleeding, tooth mobility, tooth extraction and missing teeth. Chi-square homogeneity tests were performed to assess the main associations between the independent variable (nationality) and the dependent variables (bleeding gums, tooth mobility, tooth extraction and missing teeth). Multinomial logistic regression models were constructed to evaluate the influences of the variables age and sex and their interactions on the main associations. RESULTS: A total of 115,123 participants were included in the NHS-2006 (n = 37,327, 11.38% immigrants), NHS-2011/12 (n = 38,727, 14.39% immigrants) and NHS-2017 (n = 39,069, 13.71% immigrants). The variables directly related to periodontal disease were gum bleeding and tooth mobility. These were significantly associated with nationality in the NHS-2006 and NHS-2017 cohorts. In the NHS-2011/12 cohort, only tooth mobility was associated with nationality. After adjustments for sex, age, and their interactions, immigrant status was associated with increased odds of bleeding in only the NHS-2006 cohort (RR = 1.65, 95% CI 1.38-1.99, p = 0.000). CONCLUSION: Immigrants in Spain have a lower probability of developing signs associated with periodontal disease than the Spanish population. Among the immigrant cohort, females and those in adult age groups had lower prevalence rates than their counterparts.

HIV-1 DNA decay dynamics in early treated individuals: practical considerations for clinical trial design.

BACKGROUND: Initiation of combination antiretroviral therapy (cART) soon after HIV-1 infection limits the establishment of viral reservoirs. Thus, early treated individuals are preferred candidates to evaluate novel viral remission strategies. However, their cART-dependent HIV-1 DNA decay dynamics are still poorly defined. This can hamper the design and interpretation of results from clinical trials intended to further reduce viral reservoirs. OBJECTIVES: To clarify the duration of cART needed for the HIV-1 reservoir to be stabilized in early treated individuals. METHODS: We characterized the longitudinal decline of total HIV-1 DNA levels by droplet digital PCR in 21 individuals initiating cART within 6 months after estimated HIV-1 acquisition. Measurements were taken at cART initiation, after 6 months and annually until Year 4. Correlations between virological and clinical parameters were statistically analysed. Statistical modelling was performed applying a mixed-effects model. RESULTS: Total HIV-1 DNA experienced a median overall decrease of 1.43 log10 units (IQR = 1.17-1.69) throughout the 4 years of follow-up. Baseline levels for total HIV-1 DNA, viral load, absolute CD4+ T cell count and CD4+/CD8+ ratio correlate with final HIV-1 DNA measurements (R2 = 0.68, P < 0.001; R2 = 0.54, P = 0.012; R2 = -0.47, P = 0.031; and R2 = -0.59, P = 0.0046, respectively). Statistical modelling shows that after 2 years on cART the viral reservoir had reached a set point. CONCLUSIONS: A waiting period of 2 years on cART should be considered when designing interventions aiming to impact latent HIV-1 reservoir levels and viral rebound kinetics after cART discontinuation, in order to facilitate interpretation of results and enhance the chance of viral control.

Is there evidence for bacterial transfer via the placenta and any role in the colonization of the infant gut? - a systematic review.

With the important role of the gut microbiome in health and disease, it is crucial to understand key factors that establish the microbial community, including gut colonization during infancy. It has been suggested that the first bacterial exposure is via a placental microbiome. However, despite many publications, the robustness of the evidence for the placental microbiome and transfer of bacteria from the placenta to the infant gut is unclear and hence the concept disputed. Therefore, we conducted a systematic review of the evidence for the role of the placental, amniotic fluid and cord blood microbiome in healthy mothers in the colonization of the infant gut. Most of the papers which were fully assessed considered placental tissue, but some studied amniotic fluid or cord blood. Great variability in methodology was observed especially regarding sample storage conditions, DNA/RNA extraction, and microbiome characterization. No study clearly considered transfer of the normal placental microbiome to the infant gut. Moreover, some studies in the review and others published subsequently reported little evidence for a placental microbiome in comparison to negative controls. In conclusion, current data are limited and provide no conclusive evidence that there is a normal placental microbiome which has any role in colonization of infant gut.

Malnutrition in all its forms by wealth, education and ethnicity in Latin America: who are more affected?

OBJECTIVE: To summarise the findings from this supplemental issue on the distribution of malnutrition (stunting/short stature, anaemia and overweight) by wealth, education and ethnicity within and between ten Latin American countries. DESIGN: We retrieved information from each country's article and estimated the average difference in the prevalence of malnutrition between groups. We estimated the associations between countries' malnutrition prevalence and GDP, percentage of women with high education and percentage of non-indigenous ethnicity. SETTING: Nationally representative surveys from ten Latin American countries conducted between 2005 and 2017. PARTICIPANTS: Children (<5 years), adolescent women (11-19 years) and adult women (20-49 years). RESULTS: Socially disadvantaged groups (low wealth, low education and indigenous ethnicity) had on average 15-21 (range across indicators and age groups) percentage points (pp) higher prevalence of stunting/short stature and 3-11 pp higher prevalence of anaemia. For overweight or obesity, adult women with low education had a 17 pp higher prevalence; differences were small among children <5 years, and results varied by country for adolescents by education, and for adults and adolescents by wealth and ethnicity. A moderate and strong correlation (-0·58 and -0·71) was only found between stunting/short stature prevalence and countries' GDP per capita and percentage of non-indigenous households. CONCLUSIONS: Overweight was equally distributed among children; findings were mixed for ethnicity and wealth, whereas education was a protective factor among adult women. There is an urgent need to address the deep inequalities in undernutrition and prevent the emerging inequalities in excess weight from developing further.

Biology and Therapeutic Targets of Colorectal Serrated Adenocarcinoma; Clues for a Histologically Based Treatment against an Aggressive Tumor.

Serrated adenocarcinoma (SAC) is a tumor recognized by the WHO as a histological subtype accounting for around 9% of colorectal carcinomas. Compared to conventional carcinomas, SACs are characterized by a worse prognosis, weak development of the immune response, an active invasive front and a frequent resistance to targeted therapy due to a high occurrence of KRAS or BRAF mutation. Nonetheless, several high-throughput studies have recently been carried out unveiling the biology of this cancer and identifying potential molecular targets, favoring a future histologically based treatment. This review revises the current evidence, aiming to propose potential molecular targets and specific treatments for this aggressive tumor.

Are we close to defining a metabolomic signature of human obesity? A systematic review of metabolomics studies.

INTRODUCTION: Obesity is a disorder characterized by a disproportionate increase in body weight in relation to height, mainly due to the accumulation of fat, and is considered a pandemic of the present century by many international health institutions. It is associated with several non-communicable chronic diseases, namely, metabolic syndrome, type 2 diabetes mellitus (T2DM), cardiovascular diseases (CVD), and cancer. Metabolomics is a useful tool to evaluate changes in metabolites due to being overweight and obesity at the body fluid and cellular levels and to ascertain metabolic changes in metabolically unhealthy overweight and obese individuals (MUHO) compared to metabolically healthy individuals (MHO). OBJECTIVES: We aimed to conduct a systematic review (SR) of human studies focused on identifying metabolomic signatures in obese individuals and obesity-related metabolic alterations, such as inflammation or oxidative stress. METHODS: We reviewed the literature to identify studies investigating the metabolomics profile of human obesity and that were published up to May 7th, 2019 in SCOPUS and PubMed through an SR. The quality of reporting was evaluated using an adapted of QUADOMICS. RESULTS: Thirty-three articles were included and classified according to four types of approaches. (i) studying the metabolic signature of obesity, (ii) studying the differential responses of obese and non-obese subjects to dietary challenges (iii) studies that used metabolomics to predict weight loss and aimed to assess the effects of weight loss interventions on the metabolomics profiles of overweight or obese human subjects (iv) articles that studied the effects of specific dietary patterns or dietary compounds on obesity-related metabolic alterations in humans. CONCLUSION: The present SR provides state-of-the-art information about the use of metabolomics as an approach to understanding the dynamics of metabolic processes involved in human obesity and emphasizes metabolic signatures related to obesity phenotypes.

Evidence of high 18 F-fluorodeoxyglucose uptake in the subcutaneous adipose tissue of the dorsocervical area in young adults.

NEW FINDINGS: What is the central question of this study? In some studies, biopsies have been performed of the subcutaneous adipose tissue in the abdomen, and they failed to find browning markers. Is the abdomen the right place to take biopsies? What is the main finding and its importance? For first time, we observed that the glucose uptake in the dorsocervical subcutaneous adipose tissue is higher in comparison to other areas of subcutaneous adipose tissue. ABSTRACT: Neonates have subcutaneous brown adipose tissue (BAT) in the dorsocervical area, and it is thought that these depots gradually disappear with age. Here, we determined that young adults have high 18 F-flurodeoxyglucose (18 F-FDG) uptake in the subcutaneous adipose tissue (SAT) of the dorsocervical area. A total of 133 young adults (age 22 ± 2 years; body mass index 25 ± 5 kg m2 ) were included in the study. We performed a shivering threshold test for every participant. Later, we performed 2 h of personalized cold exposure, immediately before a positron emission tomography/computed tomography scan. We showed that 23 of 133 participants had 18 F-FDG uptake in the dorsocervical area that achieved the criteria to be considered BAT, mainly in women (96%, n = 22 of 23). In the whole sample, the glucose uptake in the SAT of the dorsocervical area was positively correlated with BAT volume and activity located in the supraclavicular area. We showed that the 18 F-FDG uptake of the SAT of the dorsocervical area in humans is different from that of other SAT areas. Future studies are warranted to confirm the brown signature of this tissue.

The chemical physics of sequential infiltration synthesis-A thermodynamic and kinetic perspective.

Sequential infiltration synthesis (SIS) is an emerging materials growth method by which inorganic metal oxides are nucleated and grown within the free volume of polymers in association with chemical functional groups in the polymer. SIS enables the growth of novel polymer-inorganic hybrid materials, porous inorganic materials, and spatially templated nanoscale devices of relevance to a host of technological applications. Although SIS borrows from the precursors and equipment of atomic layer deposition (ALD), the chemistry and physics of SIS differ in important ways. These differences arise from the permeable three-dimensional distribution of functional groups in polymers in SIS, which contrast to the typically impermeable two-dimensional distribution of active sites on solid surfaces in ALD. In SIS, metal-organic vapor-phase precursors dissolve and diffuse into polymers and interact with these functional groups through reversible complex formation and/or irreversible chemical reactions. In this perspective, we describe the thermodynamics and kinetics of SIS and attempt to disentangle the tightly coupled physical and chemical processes that underlie this method. We discuss the various experimental, computational, and theoretical efforts that provide insight into SIS mechanisms and identify approaches that may fill out current gaps in knowledge and expand the utilization of SIS.

Identification and functional analysis of missense mutations in the lecithin cholesterol acyltransferase gene in a Chilean patient with hypoalphalipoproteinemia.

BACKGROUND: Lecithin-cholesterol acyltransferase (LCAT) is a plasma enzyme that esterifies cholesterol in high- and low-density lipoproteins (HDL and LDL). Mutations in LCAT gene causes familial LCAT deficiency, which is characterized by very low plasma HDL-cholesterol levels (Hypoalphalipoproteinemia), corneal opacity and anemia, among other lipid-related traits. Our aim is to evaluate clinical/biochemical features of a Chilean family with a proband showing clinical signs of familial LCAT deficiency, as well as to identify and assess the functional effects of LCAT mutations. METHODS: An adult female proband with hypoalphalipoproteinemia, corneal opacity and mild anemia, as well as her first-degree relatives, were recruited for clinical, biochemical, genetic, in-silico and in-vitro LCAT analysis. Sequencing of exons and intron-exon boundaries was performed to identify mutations. Site-directed mutagenesis was carried out to generate plasmids containing cDNA with wild type or mutant sequences. Such expression vectors were transfected to HEK-239 T cells to asses the effect of LCAT variants in expression, synthesis, secretion and enzyme activity. In-silico prediction analysis and molecular modeling was also used to evaluate the effect of LCAT variants. RESULTS: LCAT sequencing identified rare p.V333 M and p.M404 V missense mutations in compound heterozygous state in the proband, as well the common synonymous p.L363 L variant. LCAT protein was detected in proband's plasma, but with undetectable enzyme activity compared to control relatives. HEK-293 T transfected cells with vector expression plasmids containing either p.M404 V or p.V333 M cDNA showed detectable LCAT protein expression both in supernatants and lysates from cultured cells, but with much lower enzyme activity compared to cells transfected with the wild-type sequence. Bioinformatic analyses also supported a causal role of such rare variations in LCAT lack of function. Additionally, the proband carried the minor allele of the synonymous p.L363 L variant. However, this variant is unlikely to affect the clinical phenotype of the proband given its relatively high frequency in the Chilean population (4%) and its small putative effect on plasma HDL-cholesterol levels. CONCLUSION: Genetic, biochemical, in vitro and in silico analyses indicate that the rare mutations p.M404 V and p.V333 M in LCAT gene lead to suppression of LCAT enzyme activity and cause clinical features of familial LCAT deficiency.

Vitamin D: Classic and Novel Actions.

BACKGROUND: Classically, vitamin D has been implicated in bone health by promoting calcium absorption in the gut and maintenance of serum calcium and phosphate concentrations, as well as by its action on bone growth and reorganization through the action of osteoblasts and osteoclasts cells. However, in the last 2 decades, novel actions of vitamin D have been discovered. The present report summarizes both classic and novel actions of vitamin D. SUMMARY: 1,25(OH)2 vitamin D, the active metabolite of vitamin D, also known as calcitriol, regulates not only calcium and phosphate homeostasis but also cell proliferation and differentiation, and has a key a role to play in the responses of the immune and nervous systems. Current effects of vitamin D include xenobiotic detoxification, oxidative stress reduction, neuroprotective functions, antimicrobial defense, immunoregulation, anti-inflammatory/anticancer actions, and cardiovascular benefits. The mechanism of action of calcitriol is mediated by the vitamin D receptor, a subfamily of nuclear receptors that act as transcription factors into the target cells after forming a heterodimer with the retinoid X receptor. This kind of receptors has been found in virtually all cell types, which may explain its multiple actions on different tissues. Key Messages: In addition to classic actions related to mineral homeostasis, vitamin D has novel actions in cell proliferation and differentiation, regulation of the innate and adaptative immune systems, preventive effects on cardiovascular and neurodegenerative diseases, and even antiaging effects.