Validation of a Food Frequency Questionnaire to Assess Intake of n-3 Polyunsaturated Fatty Acids in Switzerland

Participatory Research in Clinical Studies: An Innovative Approach to Co-creating Nutritional and Physical Activity Recommendations for Older Adults With Sarcopenia (FOOP-Sarc Project)

BACKGROUND

Participating in co-creation processes can improve the knowledge, satisfaction and healthcare outcomes of volunteers. However, this methodology is still underused in nutritional clinical studies.

OBJECTIVE

This study aimed to use participatory research as an innovative approach to co-creating nutritional and physical activity (PA) recommendations for the FOOP-Sarc project and to assess their usability and volunteers' satisfaction and engagement experience (SEE) during the co-creation process.

DESIGN

The co-creation process was based on four stages: (s1) co-ideation, (s2) co-design, (s3) co-implementation and (s4) co-evaluation (Ref.: NCT05485402).

SETTING AND PARTICIPANTS

Thirteen volunteers with sarcopenia were included (stages 1-2 [n = 7], stage 3 [n = 3 intervention, n = 3 control] and stage 4 [n = 13]).

MEASURES

The co-ideation (s1) and co-design (s2) stages focused on designing recommendations adapted to the volunteers' preferences; the co-implementation (s3) stage included the implementation and comparison of the co-created or standard recommendations for 3 weeks to test the recommendations' acceptance; and the co-evaluation (s4) stage focused on usability, SEE, and adherence.

RESULTS

The volunteers co-created recommendations for improving sarcopenia according to the barriers identified related to diet and PA. The recommendations' usability and the SEE of volunteers were high in all cases.

CONCLUSIONS

The participatory research approach used in this nutritional intervention study, demonstrates a high usability of the co-created recommendations for sarcopenia and high SEE of the volunteers, particularly in the volunteers who participated in co-ideation (s1) and co-design (s2), the most key stages of the co-creation process.

PATIENT OR PUBLIC CONTRIBUTION

The volunteers in this study participated in the co-creation of nutritional and PA recommendations to improve sarcopenia, which they must subsequently follow.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT05485402.

Size of lipid emulsion droplets influences metabolism in human CD4+ T cells

SCOPE

Triglyceride-based lipid emulsions are critical for total parenteral nutrition (TPN), but their long-term use has adverse effects, such as severe liver dysfunction necessitating improved formulations. This study compares the uptake mechanism and intracellular fate of novel glycerol-stabilized nano-sized lipid emulsions with conventional emulsions in CD4+ T cells, focusing on their impact on cellular metabolism.

METHODS AND RESULTS

Nanoemulsions were formulated with increased glycerol content. Uptake of emulsions in primary human CD4+ T cells was investigated using different endocytic blockers, then quantified by flow cytometry, and visualized by confocal microscopy. To investigate emulsion intracellular fate, fatty acids in membrane phospholipids were quantified by GC-MS/MS and cellular metabolism was assessed by Seahorse technology. Results show T cells internalize both conventional and nano-sized emulsions using macropinocytosis. Fatty acids from emulsions are stored as neutral lipids in intracellular vesicles and are incorporated into phospholipids of cellular membranes. However, only nanoemulsions additionally use clathrin-mediated endocytosis and deliver fatty acids to mitochondria for increased β-oxidation.

CONCLUSIONS

Size of lipid emulsion droplets significantly influences their uptake and subsequent metabolism in CD4+ T cells. Our results highlight the potential for improved nutrient utilization with nanoemulsions in TPN formulations possibly leading to less adverse effects.

Mental health in society's margins: poor n-3 PUFA intake and psychological well-being of homeless youth

Dietary intake of long-chain n-3 PUFA (n-3 PUFA), particularly EPA and DHA, has been associated with psychological well-being, but little is known about the n-3 PUFA intake of homeless youth. The current study determined the association between depression and anxiety symptoms and n-3 PUFA intake and erythrocytes status in homeless youth. Totally, 114 homeless youth aged 18-24 years were recruited from a drop-in centre. n-3 PUFA dietary intake was assessed using an FFQ, and erythrocytes status was determined by gas chromatography (GC). Linear regression models were used to determine the relationship between psychological well-being and n-3 PUFA intake and status. The mean intakes of EPA and DHA for all participants (0·06 ± 0·13 g/d and 0·11 ± 0·24 g/d) were well below recommended levels, and mean erythrocytes EPA + DHA (n-3 index) in the cohort (2·42 %) was lower than reported for healthy, housed adolescents and those with clinical depression. There was no association of n-3 PUFA intake and erythrocytes status with either depression or anxiety. However, the relationships of depression with dietary EPA (P = 0·017) and DHA (P = 0·008), as well as erythrocytes DHA (P = 0·007) and n 3-index (P = 0·009), were significantly moderated by sex even after adjusting for confounders. Specifically, among females, as the intake and status of these n-3 PUFA decreased, depression increased. Our findings show poor dietary intake and low erythrocytes status of n-3 PUFA among homeless youth, which is associated with depressive symptoms among females.

Omega-3 fatty acid supply in pregnancy for risk reduction of preterm and early preterm birth

This clinical practice guideline on the supply of the omega-3 docosahexaenoic acid and eicosapentaenoic acid in pregnant women for risk reduction of preterm birth and early preterm birth was developed with support from several medical-scientific organizations, and is based on a review of the available strong evidence from randomized clinical trials and a formal consensus process. We concluded the following. Women of childbearing age should obtain a supply of at least 250 mg/d of docosahexaenoic+eicosapentaenoic acid from diet or supplements, and in pregnancy an additional intake of ≥100 to 200 mg/d of docosahexaenoic acid. Pregnant women with a low docosahexaenoic acid intake and/or low docosahexaenoic acid blood levels have an increased risk of preterm birth and early preterm birth. Thus, they should receive a supply of approximately 600 to 1000 mg/d of docosahexaenoic+eicosapentaenoic acid, or docosahexaenoic acid alone, given that this dosage showed significant reduction of preterm birth and early preterm birth in randomized controlled trials. This additional supply should preferably begin in the second trimester of pregnancy (not later than approximately 20 weeks' gestation) and continue until approximately 37 weeks' gestation or until childbirth if before 37 weeks' gestation. Identification of women with inadequate omega-3 supply is achievable by a set of standardized questions on intake. Docosahexaenoic acid measurement from blood is another option to identify women with low status, but further standardization of laboratory methods and appropriate cutoff values is needed. Information on how to achieve an appropriate intake of docosahexaenoic acid or docosahexaenoic+eicosapentaenoic acid for women of childbearing age and pregnant women should be provided to women and their partners.

Associations of n-3 polyunsaturated fatty acid status and intake with paediatric major depressive disorder in Swiss adolescents: A case-control study

BACKGROUND

Observational studies suggest a link between n-3 polyunsaturated fatty acid (PUFA) intake, n-3 PUFA status, and depression in adults, but studies in adolescents are scarce. This study aimed to determine associations of n-3 PUFA status and intake with paediatric major depressive disorder (pMDD) in Swiss adolescents.

METHODS

We conducted a matched case-control study in 95 adolescents diagnosed with pMDD and 95 healthy controls aged 13 to <18 years. We analysed red blood cell (RBC) fatty acid (FA) composition (% of total FA). n-3 PUFA intake was assessed using a focused food frequency questionnaire and depression severity was assessed by the Children's Depression Rating Scale-Revised (CDRS-R).

RESULTS

Mean RBC eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) were lower in cases than controls (EPA: 0.41 ± 0.11 vs 0.46 ± 0.12, p < 0.001; DHA: 4.07 ± 1.04 vs 4.73 ± 1.04, p < 0.001). Subsequently, the mean RBC n-3 index was lower (4.51 ± 1.10 vs 5.20 ± 1.11, p < 0.001) and the n-6/n-3 PUFA ratio higher (5.51 ± 1.25 vs 4.96 ± 1.08, p < 0.001) in cases than controls. Adolescents with a higher n-3 index had lower odds for depression (OR = 0.49 [95% CI: 0.32-0.71]). In contrast, the n-6/n-3 PUFA ratio was associated with higher odds for depression (OR = 1.58 [95% CI: 1.14-2.25]). Intake of alpha-linolenic acid, EPA and DHA did not differ between cases and controls.

CONCLUSION

Our results suggest that a higher RBC n-3 PUFA status during adolescence is associated with a lower risk for pMDD, whereas a higher n-6/n-3 PUFA ratio is associated with a higher risk for pMDD. Differences in n-3 PUFA intake did not explain the observed differences in n-3 PUFA status.

Biomarker-based validation of a food frequency questionnaire for the assessment of omega-3 fatty acid status in a healthy Iranian population

There is no valid instrument to assess n-3 polyunsaturated fatty acids (n-3 PUFAs) intake in Iran. This study aims to develop a food frequency questionnaire (FFQ) that estimates the intake of n-3 PUFA and validate it in a healthy Iranian population based on the n-3 PUFA content of red blood cells (RBCs) and a 3-day food record (FR). A healthy population (n = 221) was recruited between February and July 2021. Participants completed the new FFQ and 3-day FR to evaluate the average intake of n-3 PUFAs. We used gas chromatography to assess the n-3 PUFA content of RBCs. To validate the FFQ based on FR and biomarker as references, the correlation coefficient was calculated. According to the Bland-Altman plots, a good agreement was found between the new FFQ and FR. Moreover, absolute intake values of ALA, EPA, DPA, DHA, and total n-3 PUFAs based on FFQ were positively correlated to their respective RBC membrane levels (coefficients between 0.205 and 0.508, p < 0.005) and FR (coefficients between 0.771 and 0.827, p < 0.001). This new FFQ is a valid instrument that can be applied to estimate the n-3 PUFA status of healthy Iranian adults.

Dietary Intake, Biological Status, and Barriers towards Omega-3 Intake in Elite Level (Tier 4), Female Athletes: Pilot Study

Omega-3 polyunsaturated fatty acids (n-3 PUFA) have unique properties which benefit athlete populations. The literature investigating NCAA collegiate, rugby sevens and German endurance athletes indicates suboptimal n-3 PUFA dietary intake and biological status. The aims of this study were: (i) to explore the dietary intakes and FA profiles of elite level, team-based, female athletes and (ii) to understand perceived barriers towards achieving n-3 dietary guidelines. A total of 35 athletes (24.8 ± 4.5 years) completed both a questionnaire and a finger prick test. All the participants reported consuming fish and seafood over the previous six months however only nine athletes consumed ≥ 2 servings of fish per week. Four participants reported using an n-3 supplement. The mean omega-3 index (O3I; including supplementers) was below target levels of >8% (5.19 ± 0.86%). O3I was significantly higher (p < 0.001) in those consuming ≥ 2 servings of fish per week and/or supplements (5.91 ± 0.81%) compared with those who did not (4.82 ± 0.63%). The main barriers reported by those not consuming two servings of fish per week were sensory (n = 11; 42%), cooking skills (n = 10; 38%) and knowledge of n-3 benefits (n = 7; 27%). The current study shows that elite level female athletes present with suboptimal n-3 dietary intake and O3I due to their food preferences, cooking skills and n-3 knowledge.

Perturbations in fatty acid metabolism and collagen production infer pathogenicity of a novel MBTPS2 variant in Osteogenesis imperfecta

Osteogenesis imperfecta (OI) is a heritable and chronically debilitating skeletal dysplasia. Patients with OI typically present with reduced bone mass, tendency for recurrent fractures, short stature and bowing deformities of the long bones. Mutations causative of OI have been identified in over 20 genes involved in collagen folding, posttranslational modification and processing, and in bone mineralization and osteoblast development. In 2016, we described the first X-linked recessive form of OI caused by MBTPS2 missense variants in patients with moderate to severe phenotypes. MBTPS2 encodes site-2 protease, a Golgi transmembrane protein that activates membrane-tethered transcription factors. These transcription factors regulate genes involved in lipid metabolism, bone and cartilage development, and ER stress response. The interpretation of genetic variants in MBTPS2 is complicated by the gene's pleiotropic properties; MBTPS2 variants can also cause the dermatological conditions Ichthyosis Follicularis, Atrichia and Photophobia (IFAP), Keratosis Follicularis Spinulosa Decalvans (KFSD) and Olmsted syndrome (OS) without skeletal abnormalities typical of OI. Using control and patient-derived fibroblasts, we previously identified gene expression signatures that distinguish MBTPS2-OI from MBTPS2-IFAP/KFSD and observed stronger suppression of genes involved in fatty acid metabolism in MBTPS2-OI than in MBTPS2-IFAP/KFSD; this was coupled with alterations in the relative abundance of fatty acids in MBTPS2-OI. Furthermore, we observed a reduction in collagen deposition in the extracellular matrix by MBTPS2-OI fibroblasts. Here, we extrapolate our observations in the molecular signature unique to MBTPS2-OI to infer the pathogenicity of a novel MBTPS2 c.516A>C (p.Glu172Asp) variant of unknown significance in a male proband. The pregnancy was terminated at gestational week 21 after ultrasound scans showed bowing of femurs and tibiae and shortening of long bones particularly of the lower extremity; these were further confirmed by autopsy. By performing transcriptional analyses, gas chromatography-tandem mass spectrometry-based quantification of fatty acids and immunocytochemistry on fibroblasts derived from the umbilical cord of the proband, we observed perturbations in fatty acid metabolism and collagen production similar to what we previously described in MBTPS2-OI. These findings support pathogenicity of the MBTPS2 variant p.Glu172Asp as OI-causative and highlights the value of extrapolating molecular signatures identified in multiomics studies to characterize novel genetic variants.

Association of plasma zinc levels with anti-SARS-CoV-2 IgG and IgA seropositivity in the general population: A case-control study

INTRODUCTION

Some micronutrients have key roles in immune defence, including mucosal defence mechanisms and immunoglobulin production. Altered micronutrient status has been linked with COVID-19 infection and disease severity. We assessed the associations of selected circulating micronutrients with anti-SARS-CoV-2 IgG and IgA seropositivity in the Swiss community using early pandemic data.

METHODS

Case-control study comparing the first PCR-confirmed COVID-19 symptomatic cases in the Vaud Canton (May to June 2020, n = 199) and controls (random population sample, n = 447), seronegative for IgG and IgA. The replication analysis included seropositive (n = 134) and seronegative (n = 152) close contacts from confirmed COVID-19 cases. Anti-SARS-CoV-2 IgG and IgA levels against the native trimeric spike protein were measured using the Luminex immunoassay. We measured plasma Zn, Se and Cu concentrations by ICP-MS, and 25-hydroxy-vitamin D₃ (25(OH)D₃) with LC-MS/MS and explored associations using multiple logistic regression.

RESULTS

The 932 participants (54.1% women) were aged 48.6 ± 20.2 years (±SD), BMI 25.0 ± 4.7 kg/m² with median C-Reactive Protein 1 mg/l. In logistic regressions, log₂(Zn) plasma levels were negatively associated with IgG seropositivity (OR [95% CI]: 0.196 [0.0831; 0.465], P < 0.001; replication analyses: 0.294 [0.0893; 0.968], P < 0.05). Results were similar for IgA. We found no association of Cu, Se, and 25(OH)D₃ with anti-SARS-CoV-2 IgG or IgA seropositivity.

CONCLUSION

Low plasma Zn levels were associated with higher anti-SARS-CoV-2 IgG and IgA seropositivity in a Swiss population when the initial viral variant was circulating, and no vaccination available. These results suggest that adequate Zn status may play an important role in protecting the general population against SARS-CoV-2 infection.

REGISTRY

CORONA IMMUNITAS:: ISRCTN18181860.

Prospective dietary polyunsaturated fatty acid intake is associated with trajectories of fatty liver disease: an 8 year follow-up study from adolescence to young adulthood

BACKGROUND AND AIM

Dietary fat intake has long been associated with fatty liver. Our study aimed to determine the effect of dietary fats on longitudinal fatty liver index (FLI) trajectories from adolescence to young adulthood.

METHODS

Nine hundred eighty-five participants in the Raine Study, Perth, Western Australia, Australia, had cross-sectional assessments at ages 14, 17, 20 and 22 years, during which anthropometric measurements and blood tests were obtained. FLI trajectories were derived from the longitudinal FLI results. Dietary fat intake was measured with a semi-quantitative food frequency questionnaire at 14 years and log multinominal regression analyses were used to estimate relative risks.

RESULTS

Three FLI trajectories were identified and labelled as stable-low (79.1%, N = 782), low-to-high (13.9%, N = 132), and stable-high (7%, N = 71). The low-to-high group associated with an increased intake of the long-chain polyunsaturated fatty acids EPA, DPA and DHA (RR 1.27, 95% CI 1.10-1.48) relative to the stable-low group. Compared to the stable-low group, omega-6 and the ratio of omega-6 to omega-3 in the stable-high group were associated with an increased relative risk of 1.34 (95% CI 1.02-1.76) and 1.10 (95% CI 1.03-1.16), respectively.

CONCLUSION

For those at high risk of fatty liver in early adolescence, high omega-6 fatty acid intake and a high ratio of omega-6 to omega-3 fatty acids are associated with increased risk of fatty liver. There should be caution in assuming these associations are causal due to possible undetected and underestimated confounding factors.

Lipid emulsion rich in n-3 polyunsaturated fatty acids elicits a pro-resolution lipid mediator profile in mouse tissues and in human immune cells

BACKGROUND

Lipid emulsions are a key component of total parenteral nutrition (TPN) and are administered to patients who are unable to ingest their daily required calories orally. Lipid emulsions rich with n-6 (ω-6) PUFAs are known to cause parenteral nutrition-associated liver disease and have inflammatory side effects, whereas n-3 PUFA-rich emulsions have favourable clinical outcomes.

OBJECTIVES

The present study used targeted lipid mediator analysis to investigate the metabolism of a n-3 PUFA-rich lipid emulsion and a n-6 PUFA-rich lipid emulsion in a mouse model of TPN and in primary human monocyte-derived macrophages (MDMs) and CD4+ T cells.

RESULTS

Mice given n-3 PUFA-based TPN for 7 d had a less proinflammatory lipid mediator profile compared with those receiving n-6 PUFA-based TPN. This was characterized by higher concentrations of specialized pro-resolving mediators (SPMs) and endocannabinoids, including resolvin D (RvD) 1, maresin (MaR) 1, MaR2, protectin D1 (PD1), protectin DX (PDX), and the endocannabinoids eicosapentaenoyl ethanolamide (EPEA) and docosahexaenoyl ethanolamide (DHEA) in the liver and RvD1, 17R-RvD1, RvD2, RvD3, RvD5, MaR1, MaR2, PD1, PDX, and EPEA and DHEA in the spleen. The spleen was identified as a source of high lipid mediator and SPM formation as lipid mediator concentrations were on average 25-fold higher than in the liver. Additionally, n-3 PUFA-treated primary human MDMs produced RvD5 and the endocannabinoids EPEA and DHEA, which was associated with an increased IL-10 secretion. In contrast, primary human CD4+ T cells showed only an increase in SPM precursors and an increase in the endocannabinoids EPEA and DHEA, which was associated with reduced cytokine expression.

CONCLUSIONS

This demonstrates that lipid mediators, particularly SPMs and endocannabinoids from spleen, could play a key role in facilitating the favorable clinical outcomes associated with the use of n-3 PUFA-rich lipid emulsions in TPN.

Omega-3 polyunsaturated fatty acids: moving towards precision use for prevention and treatment of colorectal cancer

Data from experimental studies have demonstrated that marine omega-3 polyunsaturated fatty acids (O3FAs) have anti-inflammatory and anticancer properties. In the last decade, large-scale randomised controlled trials of pharmacological delivery of O3FAs and prospective cohort studies of dietary O3FA intake have continued to investigate the relationship between O3FA intake and colorectal cancer (CRC) risk and mortality. Clinical data suggest that O3FAs have differential anti-CRC activity depending on several host factors (including pretreatment blood O3FA level, ethnicity and systemic inflammatory response) and tumour characteristics (including location in the colorectum, histological phenotype (eg, conventional adenoma or serrated polyp) and molecular features (eg, microsatellite instability, cyclooxygenase expression)). Recent data also highlight the need for further investigation of the effect of O3FAs on the gut microbiota as a possible anti-CRC mechanism, when used either alone or in combination with other anti-CRC therapies. Overall, these data point towards a precision approach to using O3FAs for optimal prevention and treatment of CRC based on mechanistic understanding of host, tumour and gut microbiota factors that predict anticancer activity of O3FAs.

Validation of an abbreviated food frequency questionnaire for estimating DHA intake of pregnant women in the United States

Docosahexaenoic acid (DHA) intake was estimated in pregnant women between 12- and 20-weeks' gestation using the National Cancer Institute's (NCI) Diet History Questionnaire-II (DHQ-II) and a 7-question screener designed to capture DHA intake (DHA Food Frequency Questionnaire, DHA-FFQ). Results from both methods were compared to red blood cell phospholipid DHA (RBC-DHA) weight percent of total fatty acids. DHA intake from the DHA-FFQ was more highly correlated with RBC-DHA (r_s=0.528) than the DHQ-II (r_s=0.352). Moreover, the DHA-FFQ allowed us to obtain reliable intake data from 1355 of 1400 participants. The DHQ-II provided reliable intake for only 847 of 1400, because many participants only partially completed it and it was not validated for Hispanic participants. Maternal age, parity, and socioeconomic status (SES) were also significant predictors of RBC-DHA. When included with estimated intake from the DHA-FFQ, the model accounted for 36% of the variation in RBC-DHA.

Intake of n-3 LCPUFA and trans-fatty acids is unrelated to development in body mass index and body fat among children

BACKGROUND

The number of children and adolescents with obesity has increased worldwide. Some studies have found an increase in the intake of n-3 long-chain polyunsaturated fatty acid (LCPUFA) to be beneficial for weight and obesity status. The objectives of this study were to examine if intake of trans-fatty acids (TFA) and n-3 LCPUFA at school start was associated with weight and body fat development in the following 3 and 7 years, and if substituting other fats for n-3 LCPUFA in regression models influenced weight and body fat development.

METHODS

A total of 285 children (boys:130, girls:155) were included in this study. Weight, height and skinfold thickness (SF) of children were measured at age 6, 9 and 13 years by trained research personnel. Multivariate linear regression models were used to investigate the associations between n-3 LCPUFA or TFA intake and subsequent changes in body mass index (BMI) or SF. To investigate substitution effects, we constructed regression models including information on n-3 LCPUFA and all other energy given components of the diet, except for the nutrient to be substituted (all other fats and specific subgroups; saturated fatty acids (SFAs), monounsaturated fatty acids (MUFAs) and other polyunsaturated fatty acids (PUFAs)).

RESULTS

No significant associations were observed between intake of TFA or n-3 LCPUFA and changes in BMI and SF. Also, results from regression analysis showed substituting other fats for n-3 LCPUFA did not associate with BMI or SF development.

CONCLUSION

The lack of associations between n-3 LCPUFA and TFA and adiposity suggests that fat composition in the diet does not play a major role in obesity development among school-aged children.

Development and validation of a food frequency questionnaire for children aged 7 to 10 years

ABSTRACT Objective Food and nutritional evaluation of children can support public policies to combat early overweight and obesity. This study developed and validated a quantitative food frequency questionnaire for assessing the dietary intake of children. Methods This is a cross-sectional study of the development of a food frequency questionnaire for 130 children of both genders aged 7 to 10 years old. For the food frequency questionnaire list, 81 food items were selected. The validity of the food frequency questionnaire was evaluated by comparison with 24-hour recalls and reproducibility was performed by comparing two food frequency questionnaires. Results Most of the foods with 95% relative contribution were ultra-processed, such as packaged snacks and powdered juice. In validation, correlation coefficients were found between 0.45 (p<0.000) for lipids and 0.37 (p<0.000) for carbohydrates. An adjustment for energy reduced the correlations, but there was an increase in the correlation in calcium (r=0.75) and retinol (r=0.20). In terms of reproducibility, all macronutrients and calcium showed a satisfactory intraclass correlation coefficient (>0.400) and moderate correlations [proteins (0.54; p<0.000) and lipids (0.41; p<0.000)]. Conclusion The food frequency questionnaire developed was valid and able to assess the local food consumption by children from northeastern Brazil.

Development and Validation of a Mobile Phone Application Developed for Measuring Dietary Fiber Intake

We have developed a mobile phone application for measuring the intake of dietary fiber and validated the ability of the application to accurately capture this intake against measurements registered by a dietary record. We also investigated what food groups contributed most to the total, soluble, and insoluble dietary fiber intake. Twenty-six randomly selected Swedish women aged 35–85 years were included and randomized to either start to register dietary intake in the application or by a dietary record, during three consecutive days. After a washout period of at least two weeks, the participants used the other method. We found that the difference in measured mean fiber intake between the dietary record and the application was two grams independent of the total intake per day. A statistically significant correlation between fiber intake as measured by the two methods was found (rho = 0.65, p < 0.001). Vegetables and roots were the predominantly contributing foods to total and soluble fiber intake. Bread and crackers contributed most to insoluble fiber intake. In conclusion, the application may be considered as a useful and easy-to-use method to measure dietary fiber intake.

Omics Profiling of S2P Mutant Fibroblasts as a Mean to Unravel the Pathomechanism and Molecular Signatures of X-Linked MBTPS2 Osteogenesis Imperfecta

Osteogenesis imperfecta (OI) is an inherited skeletal dysplasia characterized by low bone density, bone fragility and recurrent fractures. The characterization of its heterogeneous genetic basis has allowed the identification of novel players in bone development. In 2016, we described the first X-linked recessive form of OI caused by hemizygous MBTPS2 missense variants resulting in moderate to severe phenotypes. MBTPS2 encodes site-2 protease (S2P), which activates transcription factors involved in bone (OASIS) and cartilage development (BBF2H7), ER stress response (ATF6) and lipid metabolism (SREBP) via regulated intramembrane proteolysis. In times of ER stress or sterol deficiency, the aforementioned transcription factors are sequentially cleaved by site-1 protease (S1P) and S2P. Their N-terminal fragments shuttle to the nucleus to activate gene transcription. Intriguingly, missense mutations at other positions of MBTPS2 cause the dermatological spectrum condition Ichthyosis Follicularis, Atrichia and Photophobia (IFAP) and Keratosis Follicularis Spinulosa Decalvans (KFSD) without clinical overlap with OI despite the proximity of some of the pathogenic variants. To understand how single amino acid substitutions in S2P can lead to non-overlapping phenotypes, we aimed to compare the molecular features of MBTPS2-OI and MBTPS2-IFAP/KFSD, with the ultimate goal to unravel the pathomechanisms underlying MBTPS2-OI. RNA-sequencing-based transcriptome profiling of primary skin fibroblasts from healthy controls (n = 4), MBTPS2-OI (n = 3), and MBTPS2-IFAP/KFSD (n = 2) patients was performed to identify genes that are differentially expressed in MBTPS2-OI and MBTPS2-IFAP/KFSD individuals compared to controls. We observed that SREBP-dependent genes are more downregulated in OI than in IFAP/KFSD. This is coupled to alterations in the relative abundance of fatty acids in MBTPS2-OI fibroblasts in vitro, while no consistent alterations in the sterol profile were observed. Few OASIS-dependent genes are suppressed in MBTPS2-OI, while BBF2H7- and ATF6-dependent genes are comparable between OI and IFAP/KFSD patients and control fibroblasts. Importantly, we identified genes involved in cartilage physiology that are differentially expressed in MBTPS2-OI but not in MBTPS2-IFAP/KFSD fibroblasts. In conclusion, our data provide clues to how pathogenic MBTPS2 mutations cause skeletal deformities via altered fatty acid metabolism or cartilage development that may affect bone development, mineralization and endochondral ossification.

Strengthening the immunity of the Swiss population with micronutrients: A narrative review and call for action

BACKGROUND

The enormous health impact of the COVID-19 pandemic has refocused attention on measures to optimize immune function and vaccine response. Dietary deficiencies of micronutrients can weaken adaptive immunity. The aim of this review was to examine links between micronutrients, immune function and COVID-19 infection, with a focus on nutritional risks in subgroups of the Swiss population.

METHODS

Scoping review on the associations between selected micronutrients (vitamins D and C, iron, selenium, zinc, and n-3 PUFAs) and immunity, with particular reference to the Swiss population. These nutrients were chosen because previous EFSA reviews have concluded they play a key role in immunity.

RESULTS

The review discusses the available knowledge on links between sufficient nutrient status, optimal immune function, and prevention of respiratory tract infections. Because of the rapid spread of the COVID-19 pandemic, controlled intervention studies of micronutrients in the context of COVID-19 infection are now underway, but evidence is not yet available to draw conclusions. The anti-inflammatory properties of n-3 PUFAs are well established. In Switzerland, several subgroups of the population are at clear risk of nutrient deficiencies; e.g., older adults, multiple comorbidities, obesity, pregnancy, and institutionalized. Low intakes of n-3 PUFA are present in a large proportion of the population.

CONCLUSION

There are clear and strong relationships between micronutrient and n-3 PUFA status and immune function, and subgroups of the Swiss population are at risk for deficient intakes. Therefore, during the COVID-19 pandemic, as a complement to a healthy and balanced diet, it may be prudent to consider supplementation with a combination of moderate doses of Vitamins C and D, as well as of Se, Zn and n-3 PUFA, in risk groups.

Choice of Lipid Emulsion Determines Inflammation of the Gut-Liver Axis, Incretin Profile, and Insulin Signaling in a Murine Model of Total Parenteral Nutrition

SCOPE

The aim of this study is to test whether the choice of the lipid emulsion in total parenteral nutrition (TPN), that is, n-3 fatty acid-based Omegaven versus n-6 fatty acid-based Intralipid, determines inflammation in the liver, the incretin profile, and insulin resistance.

METHODS AND RESULTS

Jugular vein catheters (JVC) are placed in C57BL/6 mice and used for TPN for 7 days. Mice are randomized into a saline group (saline infusion with oral chow), an Intralipid group (IL-TPN, no chow), an Omegaven group (OV-TPN, no chow), or a chow only group (without JVC). Both TPN elicite higher abundance of lipopolysaccharide binding protein in the liver, but only IL-TPN increases interleukin-6 and interferon-γ, while OV-TPN reduces interleukin-4, monocyte chemoattractant protein-1, and interleukin-1α. Insulin plasma concentrations are higher in both TPN, while glucagon and glucagon-like peptide-1 (GLP-1) were higher in IL-TPN. Gluconeogenesis is increased in IL-TPN and the nuclear profile of key metabolic transcription factors shows a liver-protective phenotype in OV-TPN. OV-TPN increases insulin sensitivity in the liver and skeletal muscle.

CONCLUSION

OV-TPN as opposed to IL-TPN mitigates inflammation in the liver and reduces the negative metabolic effects of hyperinsulinemia and hyperglucagonemia by "re-sensitizing" the liver and skeletal muscle to insulin.