Creation of a pandemic memory by tracing COVID-19 infections and immunity in Luxembourg (CON-VINCE).

BACKGROUND: During the COVID-19 pandemic swift implementation of research cohorts was key. While many studies focused exclusively on infected individuals, population based cohorts are essential for the follow-up of SARS-CoV-2 impact on public health. Here we present the CON-VINCE cohort, estimate the point and period prevalence of the SARS-CoV-2 infection, reflect on the spread within the Luxembourgish population, examine immune responses to SARS-CoV-2 infection and vaccination, and ascertain the impact of the pandemic on population psychological wellbeing at a nationwide level. METHODS: A representative sample of the adult Luxembourgish population was enrolled. The cohort was followed-up for twelve months. SARS-CoV-2 RT-qPCR and serology were conducted at each sampling visit. The surveys included detailed epidemiological, clinical, socio-economic, and psychological data. RESULTS: One thousand eight hundred sixty-five individuals were followed over seven visits (April 2020-June 2021) with the final weighted period prevalence of SARS-CoV-2 infection of 15%. The participants had similar risks of being infected regardless of their gender, age, employment status and education level. Vaccination increased the chances of IgG-S positivity in infected individuals. Depression, anxiety, loneliness and stress levels increased at a point of study when there were strict containment measures, returning to baseline afterwards. CONCLUSION: The data collected in CON-VINCE study allowed obtaining insights into the infection spread in Luxembourg, immunity build-up and the impact of the pandemic on psychological wellbeing of the population. Moreover, the study holds great translational potential, as samples stored at the biobank, together with self-reported questionnaire information, can be exploited in further research. TRIAL REGISTRATION: Trial registration number: NCT04379297, 10 April 2020.

No influence of supplemental dietary calcium intake on the bioavailability of spinach carotenoids in humans.

Dietary carotenoid intake, especially from fruits and vegetables, has been associated with a reduced incidence of several chronic diseases. However, its bioavailability can vary, depending on the food matrix and host factors. Recently, it has been suggested that divalent minerals negatively impinge on carotenoid bioavailability by reducing bile-salt and non-esterified fatty-acid levels in the gut, which normally aid in emulsifying carotenoids. The aim of the present study was to investigate whether supplemental Ca would negatively influence carotenoid absorption in humans. A total of twenty-five healthy, non-obese men (age: 20-46 years, BMI<30 kg/m2) were recruited for this postprandial, randomised, crossover, double-blinded trial. Following a randomised block design, each participant received (after 2-week washout periods), on three occasions separated by 1 week, 270 g of spinach-based meals (8·61 (sd 1·08) mg carotenoids/100 g fresh weight), supplemented with 0, 500 or 1000 mg of Ca (as calcium carbonate), with each participant acting as his or her own control. Blood samples were collected at regular postprandial intervals for up to 10 h following test meal intake, and standardised lunches were served. TAG-rich lipoprotein fractions were separated and carotenoid concentrations determined. AUC for meals without supplemented Ca were 22·72 (sem 2·78) nmol×h/l (lutein), 0·19 (sem 3·90) nmol×h/l (ß-carotene) and 2·80 (sem 1·75) nmol×h/l (ß-cryptoxanthin). No significant influence of supplementation with either 500 or 1000 mg of supplemental Ca was found. In conclusion, Ca - the most abundant divalent mineral in the diet - given at high but physiological concentrations, does not appear to have repercussions on the bioavailability of carotenoids from a spinach-based meal.

Advice on lifestyle changes (diet, red wine and physical activity) does not affect internal carotid and middle cerebral artery blood flow velocity in patients with carotid arteriosclerosis in a randomized controlled trial.

BACKGROUND: A Mediterranean diet, with and without small daily amounts of red wine, and physical activity reduce the risk of cerebrovascular disease and improve cognition. An increase in cerebral blood flow may be the underlying mechanism. Under normal conditions, cerebral blood flow velocity changes in the internal carotid arteries and in large basal cerebral arteries correlate closely with cerebral blood flow changes, as the diameter of these vessels hardly changes and only the smaller vessels downstream change their diameter. METHODS: A prospective randomized controlled trial was performed in 108 patients with carotid atherosclerosis (mean age 64 years, 67% men, 66% on statin therapy). Half of them were advised to follow a polyphenol-rich modified Mediterranean diet including 1-2 tomatoes, 3-5 walnuts and a bar of dark chocolate (25 g) a day and to perform moderate physical exercise for 30 min/day (lifestyle changes). Within these two groups, half of the patients were randomized either to avoid any alcohol or to drink 100 ml of red wine (women) or 200 ml of red wine (men) daily. Bilateral middle cerebral and internal carotid blood flow velocity (peak systolic, peak end-diastolic and mean) was measured at baseline and after 4 and 20 weeks using colour-coded duplex ultrasound. Insonation depth and insonation angle were used to identically place the sample volume during follow-up investigations. A general linear model with Tukey-Kramer adjustment for multiple comparisons was used to assess the primary end points. For the analysis we used the mean values of the right and left artery. RESULTS: Neither lifestyle changes nor red wine had an effect on peak systolic, peak end-diastolic or mean cerebral blood flow velocity. CONCLUSIONS: Advice on lifestyle changes, including a modified polyphenol-rich Mediterranean diet, a glass of red wine daily and physical exercise, did not affect middle cerebral and internal carotid blood flow velocity in our patient group with carotid atherosclerosis. An increase in cerebral blood flow is thus unlikely to be the cause of the reduced risk of cerebrovascular disease and improved cognitive functioning described in the literature. One possible explanation for the fact that blood flow velocity was not affected by red wine, diet and physical activity advice is that two thirds of our patients were already on statin therapy. Statins increase cerebral blood flow and vasomotor reactivity via nitric oxide.

A daily glass of red wine associated with lifestyle changes independently improves blood lipids in patients with carotid arteriosclerosis: results from a randomized controlled trial.

BACKGROUND: Physical exercise and a Mediterranean diet improve serum lipid profile. The present work studied whether red wine has an effect on top of a lipid-lowering lifestyle in patients with carotid atherosclerosis. METHODS: A prospective randomised unblinded trial was performed from 2009 to 2011 in 108 patients with carotid atherosclerosis, 65% of whom were already on statin therapy with a low mean LDL of 104.9 mg/dl. Half of them were advised to follow a modified Mediterranean diet and to perform moderate physical exercise during 30 min/day (lifestyle changes) for 20 weeks. Within these two groups half of the patients were randomised either to avoid any alcohol or to drink 100 ml of red wine (women) or 200 ml of red wine (men) daily. RESULTS: LDL was significantly lowered by 7% in the lifestyle-changes group compared to the no-lifestyle-changes group (p = 0.0296) after 20 weeks. Lifestyle changes lowered the LDL/HDL ratio after 20 weeks by 8% (p = 0.0242) and red wine independently by 13% (p = 0.0049). The effect on LDL/HDL ratio after 20 weeks was, however, more pronounced in the non-LC group. Total cholesterol (-6%; p = 0.0238) and triglycerides (-13%; p = 0.0361) were lowered significantly by lifestyle changes after 20 weeks compared to the no-lifestyle-changes group. Lipoprotein (a) was not significantly affected by any intervention. The given results are per ITT analysis. CONCLUSIONS: Lifestyle changes including a modified Mediterranean diet and physical exercise as well as a glass of red wine daily improve independently the LDL/HDL ratio in patients with carotid arteriosclerosis even though the vast majority of them was already on statin therapy.

Luxembourg Parkinson's study -comprehensive baseline analysis of Parkinson's disease and atypical parkinsonism.

Background: Deep phenotyping of Parkinson's disease (PD) is essential to investigate this fastest-growing neurodegenerative disorder. Since 2015, over 800 individuals with PD and atypical parkinsonism along with more than 800 control subjects have been recruited in the frame of the observational, monocentric, nation-wide, longitudinal-prospective Luxembourg Parkinson's study. Objective: To profile the baseline dataset and to explore risk factors, comorbidities and clinical profiles associated with PD, atypical parkinsonism and controls. Methods: Epidemiological and clinical characteristics of all 1,648 participants divided in disease and control groups were investigated. Then, a cross-sectional group comparison was performed between the three largest groups: PD, progressive supranuclear palsy (PSP) and controls. Subsequently, multiple linear and logistic regression models were fitted adjusting for confounders. Results: The mean (SD) age at onset (AAO) of PD was 62.3 (11.8) years with 15% early onset (AAO < 50 years), mean disease duration 4.90 (5.16) years, male sex 66.5% and mean MDS-UPDRS III 35.2 (16.3). For PSP, the respective values were: 67.6 (8.2) years, all PSP with AAO > 50 years, 2.80 (2.62) years, 62.7% and 53.3 (19.5). The highest frequency of hyposmia was detected in PD followed by PSP and controls (72.9%; 53.2%; 14.7%), challenging the use of hyposmia as discriminating feature in PD vs. PSP. Alcohol abstinence was significantly higher in PD than controls (17.6 vs. 12.9%, p = 0.003). Conclusion: Luxembourg Parkinson's study constitutes a valuable resource to strengthen the understanding of complex traits in the aforementioned neurodegenerative disorders. It corroborated several previously observed clinical profiles, and provided insight on frequency of hyposmia in PSP and dietary habits, such as alcohol abstinence in PD.Clinical trial registration: clinicaltrials.gov, NCT05266872.

The gut microbial metabolite formate exacerbates colorectal cancer progression.

The gut microbiome is a key player in the immunomodulatory and protumorigenic microenvironment during colorectal cancer (CRC), as different gut-derived bacteria can induce tumour growth. However, the crosstalk between the gut microbiome and the host in relation to tumour cell metabolism remains largely unexplored. Here we show that formate, a metabolite produced by the CRC-associated bacterium Fusobacterium nucleatum, promotes CRC development. We describe molecular signatures linking CRC phenotypes with Fusobacterium abundance. Cocultures of F. nucleatum with patient-derived CRC cells display protumorigenic effects, along with a metabolic shift towards increased formate secretion and cancer glutamine metabolism. We further show that microbiome-derived formate drives CRC tumour invasion by triggering AhR signalling, while increasing cancer stemness. Finally, F. nucleatum or formate treatment in mice leads to increased tumour incidence or size, and Th17 cell expansion, which can favour proinflammatory profiles. Moving beyond observational studies, we identify formate as a gut-derived oncometabolite that is relevant for CRC progression.

Whey- and Soy Protein Isolates Added to a Carrot-Tomato Juice Alter Carotenoid Bioavailability in Healthy Adults.

Recent findings suggested that proteins can differentially affect carotenoid bioaccessibility during gastro-intestinal digestion. In this crossover, randomized human trial, we aimed to confirm that proteins, specifically whey- and soy-protein isolates (WPI/SPI) impact postprandial carotenoid bioavailability. Healthy adults (n = 12 males, n = 12 females) were recruited. After 2-week washout periods, 350 g of a tomato-carrot juice mixture was served in the absence/presence of WPI or SPI (50% of the recommended dietary allowance, RDA ≈ 60 g/d). Absorption kinetics of carotenoids and triacylglycerols (TAGs) were evaluated via the triacylglycerol-rich lipoprotein (TRL) fraction response, at timed intervals up to 10 h after test meal intake, on three occasions separated by 1 week. Maximum TRL-carotenoid concentration (Cmax) and corresponding time (Tmax) were also determined. Considering both genders and carotenoids/TAGs combined, the estimated area under the curve (AUC) for WPI increased by 45% vs. the control (p = 0.018), to 92.0 ± 1.7 nmol × h/L and by 57% vs. SPI (p = 0.006). Test meal effect was significant in males (p = 0.036), but not in females (p = 0.189). In males, significant differences were found for phytoene (p = 0.026), phytofluene (p = 0.004), α-carotene (p = 0.034), and ß-carotene (p = 0.031). Cmax for total carotenoids (nmol/L ± SD) was positively influenced by WPI (135.4 ± 38.0), while significantly lowered by SPI (89.6 ± 17.3 nmol/L) vs. the control (119.6 ± 30.9, p < 0.001). Tmax did not change. The results suggest that a well-digestible protein could enhance carotenoid bioavailability, whereas the less digestible SPI results in negative effects. This is, to our knowledge, the first study finding effects of proteins on carotenoid absorption in humans.

Corrigendum: Contributing Factors and Evolution of Impulse Control Disorder in the Luxembourg Parkinson Cohort.

[This corrects the article DOI: 10.3389/fneur.2020.578924.].

Contributing Factors and Evolution of Impulse Control Disorder in the Luxembourg Parkinson Cohort.

Background: To establish the frequency of impulse control disorder (ICD) in Parkinson's disease (PD). Methods: Within the Luxembourg Parkinson's Study, PD patients were evaluated for ICD presence (score ≥ 1 on MDS-UPDRS I item 1.6), use of dopamine agonists (DA) and other medications. Results: 470 patients were enrolled. Among 217 patients without DA use, 6.9% scored positive for ICD, vs. 15.4% among 253 patients with DA use (p = 0.005). The regression analysis showed that age at PD diagnosis had only a minor impact on ICD occurrence, while there was no influence by gender or co-medications. The longitudinal study over 2 years in 156 patients demonstrated increasing ICD frequency in DA users (p = 0.005). Conclusion: This large and non-interventional study confirms that PD patients with DA treatment show higher frequency of ICD than patients without DA use. It newly demonstrates that ICD can develop independently from age, gender, or co-medications.

Protocol for a prospective, longitudinal cohort of people with COVID-19 and their household members to study factors associated with disease severity: the Predi-COVID study.

INTRODUCTION: A few major clinical factors such as sex, obesity or comorbidities have already been associated with COVID-19 severity, but there is a need to identify new epidemiological, clinical, digital and biological characteristics associated with severity and perform deep phenotyping of patients according to severity. The objectives of the Predi-COVID study are (1) to identify new determinants of COVID-19 severity and (2) to conduct deep phenotyping of patients by stratifying them according to risk of complications, as well as risk factors for infection among household members of Predi-COVID participants (the Predi-COVID-H ancillary study). METHODS AND ANALYSIS: Predi-COVID is a prospective, hybrid cohort study composed of laboratory-confirmed COVID-19 cases in Luxembourg who will be followed up remotely for 1 year to monitor their health status and symptoms. Predi-COVID-H is an ancillary cohort study on household members of index cases included in Predi-COVID to monitor symptoms and household clusters in this high-risk population. A subcohort of up to 200 Predi-COVID and 300 Predi-COVID-H participants with biological samples will be included. Severity of infection will be evaluated by occurrence and duration of hospitalisation, admission and duration of stay in intensive care units or equivalent structures, provision of and duration of supplemental oxygen and ventilation therapy, transfer to another hospital, as well as the impact of infection on daily activities following hospital discharge. ETHICS AND DISSEMINATION: The study has been approved by the National Research Ethics Committee of Luxembourg (study number 202003/07) in April 2020. An informed consent is signed by study participants. Scientific articles will be submitted to international peer-reviewed journals, along with press releases for lay audience for major results. TRIAL REGISTRATION NUMBER: NCT04380987.

The Luxembourg Parkinson's Study: A Comprehensive Approach for Stratification and Early Diagnosis.

While genetic advances have successfully defined part of the complexity in Parkinson's disease (PD), the clinical characterization of phenotypes remains challenging. Therapeutic trials and cohort studies typically include patients with earlier disease stages and exclude comorbidities, thus ignoring a substantial part of the real-world PD population. To account for these limitations, we implemented the Luxembourg PD study as a comprehensive clinical, molecular and device-based approach including patients with typical PD and atypical parkinsonism, irrespective of their disease stage, age, comorbidities, or linguistic background. To provide a large, longitudinally followed, and deeply phenotyped set of patients and controls for clinical and fundamental research on PD, we implemented an open-source digital platform that can be harmonized with international PD cohort studies. Our interests also reflect Luxembourg-specific areas of PD research, including vision, gait, and cognition. This effort is flanked by comprehensive biosampling efforts assuring high quality and sustained availability of body liquids and tissue biopsies. We provide evidence for the feasibility of such a cohort program with deep phenotyping and high quality biosampling on parkinsonism in an environment with structural specificities and alert the international research community to our willingness to collaborate with other centers. The combination of advanced clinical phenotyping approaches including device-based assessment will create a comprehensive assessment of the disease and its variants, its interaction with comorbidities and its progression. We envision the Luxembourg Parkinson's study as an important research platform for defining early diagnosis and progression markers that translate into stratified treatment approaches.

Time-of-day dependent pharmacodynamic and pharmacokinetic profiles of caffeine in rats.

This study aims to investigate the effects of caffeine on the daily rhythms of heart rate (HR), body temperature (BT) and locomotor activity (LA) in rats in relation to time-of-day of administration, as well as their possible mechanisms, particularly related to caffeine pharmacokinetics. During the pharmacodynamic study, HR, BT and LA were measured every 10 min by radiotelemetry and analysed by Cosinor. This study was divided into three periods: a control period P1, a treatment period P2 and a recovery period P3. During P2, rats of the morning group ( M(tel)) received a 25 mg/kg s.c. dose of caffeine at 08.00 while rats of the evening group ( E(tel)) received the same dose of caffeine at 20.00. The pharmacokinetic study was conducted in parallel with the telemetric study and was divided into two periods: a control period P1, and a treatment period P2. During P2, animals of the morning ( M(pk)) and the evening ( E(pk)) groups received the same treatment as the animals of the telemetric study. At the last day of P2, blood samples were drawn 0.25, 0.5, 1, 2, 4, 8, 12 and 24 h after the last morning and the last evening administration in order to determine the pharmacokinetics of M(pk) and E(pk). Our results showed that morning administration of caffeine suppressed the daily rhythmicity of LA and modified the mesors and amplitudes of the HR and BT daily rhythms, while the evening administration did not suppress the daily rhythm of LA, but altered the mesors, amplitudes and acrophases of the three rhythms, indicating a chronopharmacological effect. With respect to the pharmacokinetic effects, the area under the curve (AUC) was significantly lower in rats of E(pk) compared with M(pk), due to an increase of the total plasma clearance and the volume of distribution. Our data suggest that the chronopharmacokinetic effects of caffeine may explain, at least in part, the observed caffeine-induced modifications on the daily rhythms.

The use of saliva for assessment of cortisol pulsatile secretion by deconvolution analysis.

Cortisol is the key effector molecule of the HPA axis and is secreted in a pulsatile manner in all species studied. In order to understand cortisol signalling in health and disease, detailed analysis of hormone pulsatility is necessary. To dissect cortisol pulsatility in plasma deconvolution techniques have been applied. Blood sampling is a labour-intensive, expensive and invasive technique that causes stress and alters HPA axis activity. Therefore saliva has been extensively investigated as an alternative sample to measure cortisol. Here we use state of the art deconvolution algorithms to investigate cortisol pulsatility in saliva. Blood and saliva samples were obtained at 15-min intervals over an 8h period in 18 healthy men to analyse their diurnal cortisol levels. A multiparameter deconvolution technique was used to generate statistically significant models of cortisol secretion and elimination in plasma and saliva. The models consisted of estimates of the number, amplitude, duration and frequency of secretory bursts as well as the elimination half-life (t1/2) in a subject specific manner. No significant differences were noted between plasma and saliva with regard to the observed secretory bursts (7.8±1.5 vs. 7.0±1.4) and the interpeak interval (59.6±10.5 min vs. 61.0±11.5 min). Moreover a strong positive correlation between the numbers of peaks in both fluids was observed (r=0.83, P<0.0001). Monte Carlo simulations revealed an 84% temporal concordance between plasma and saliva peaks in all donors (P<0.05) with a mean of 1.3±0.8 plasma peaks unmatched in saliva. The percentage concordance increased to 90% when concording only the morning cortisol peaks in plasma and saliva up to 11:00 h. The deconvolution of the most distinct component of cortisol diurnal rhythm-cortisol awakening response (CAR), revealed an average 2.5±1.1 peaks based on the individual time for cortisol to return to baseline levels. In conclusion, deconvolution analysis of plasma and salivary cortisol concentration time series showed a close correlation and similar pulsatile characteristics between saliva and plasma cortisol. Similarly, Monte Carlo simulations revealed a high concordance between the peaks in these coupled time series suggesting that saliva is a suitable medium for subsequent deconvolution analysis yielding accurate and reliable models of cortisol secretion in particular during the morning hours.

A daily glass of red wine and lifestyle changes do not affect arterial blood pressure and heart rate in patients with carotid arteriosclerosis after 4 and 20 weeks.

BACKGROUND: Regular consumption of small amounts of red wine improves blood lipids. However, there is concern whether this beneficial effect might be counterbalanced by an increase in blood pressure (BP) and heart rate (HR), which are risk factors for cerebro-cardiovascular disease. In particular, we studied whether regular consumption of red wine with and without lifestyle changes (LC; healthy diet and physical activity advice) results in an increase in BP and HR. METHODS: A prospective, unblinded randomized trial was performed in 108 patients (67% men) with carotid atherosclerosis documented by ultrasound, a mean BP of 122/79 mm Hg and a mean HR of 71 bpm at inclusion in the study. Sixty-eight percent were known and treated hypertensives. The mean 24-hour BP at baseline was 122/79 mm Hg. Half of the study participants, the control group, was seen by a nurse at baseline, after 4 and after 20 weeks, and was instructed not to change their eating and physical activity habits. In the other half, a dietician performed five sessions of 30 min each (at baseline, after 1 week and after 2, 3 and 4 weeks) giving advice on healthy eating based on a Mediterranean diet and physical exercise. The recommendations given were the following: 5 portions of fruit/vegetables per day, a diet low in absolute fat, a preference of vegetable oil (olive or rapeseed oil), whole-grain products, poultry, low-fat dairy products, 1 fat and 1 lean fish meal per week, reduced consumption of red meat, and avoidance of pork, ready-made meals, sugar and excessive salt intake. In addition, regular consumption of 1 bar of dark chocolate (25 g, >70% of cacao), 1-2 tomatoes, and 3-5 walnuts as well as at least 30 min of moderate daily physical activity were recommended. Within these two groups, half of the patients were randomized either to avoid alcohol completely or to drink 100 ml (women) or 200 ml of red wine (men) daily. RESULTS: Neither LC nor red wine had an effect on the mean systolic and diastolic 24-hour BP and HR after 4 and 20 weeks, as analyzed by general linear modeling. No difference was found for diurnal and nocturnal values. CONCLUSIONS: The possible beneficial effect of regular consumption of small amounts of red wine is not counterbalanced in the long term by an increase in the mean BP or HR in mainly normotensive and well-treated hypertensive patients with carotid atherosclerosis, neither in the patients given healthy lifestyle advice nor in those with a standard lifestyle. Yet, we remain cautious about actively advice patients to drink alcohol regularly given the well-known risks.