Catalogue Search | MBRL
Search Results Heading
Explore the vast range of titles available.
MBRLSearchResults
-
DisciplineDiscipline
-
Is Peer ReviewedIs Peer Reviewed
-
Item TypeItem Type
-
SubjectSubject
-
YearFrom:-To:
-
More FiltersMore FiltersSourceLanguage
Done
Filters
Reset
33
result(s) for
"Pinto-Sietsma, Sara-Joan"
Sort by:
The role of the gut microbiome and exercise in non-alcoholic fatty liver disease
by
Boulund, Ulrika
,
Pinto-Sietsma, Sara-Joan
,
Nieuwdorp, Max
in
Clinical trials
,
Digestive system
,
Fatty liver
2020
In recent years, the human gut microbiome has been found to influence a multitude of non-communicable diseases such as cardiovascular disease and metabolic syndrome, with its components type 2 diabetes mellitus and obesity. It is recognized to be mainly influenced by environmental factors, such as lifestyle, but also genetics may play a role. The interaction of gut microbiota and obesity has been widely studied, but in regard to non-alcoholic fatty liver disease (NAFLD) as a manifestation of obesity and insulin resistance, the causal role of the gut microbiome has not been fully established. The mechanisms by which the gut microbiome influences lipid accumulation, inflammatory responses, and occurrence of fibrosis in the liver are a topic of active research.
In addition, the influence of exercise on gut microbiome composition is also being investigated. In clinical trials, exercise reduced hepatic steatosis independently of weight reduction. Other studies indicate that exercise may modulate the gut microbiome. This puts forward the question whether exercise could mediate its beneficial effects on NAFLD via changes in gut microbiome. Yet, the specific mechanisms underlying this potential connection are largely unknown. Thus, associative evidence from clinical trials, as well as mechanistic studies in vivo are called for to elucidate the relationship between exercise and the gut microbiome in NAFLD. Here, we review the current literature on exercise and the gut microbiome in NAFLD.
Journal Article
Study Design and qPCR Data Analysis Guidelines for Reliable Circulating miRNA Biomarker Experiments: A Review
by
de Ronde, Maurice W J
,
Pinto-Sietsma, Sara-Joan
,
Ruijter, Jan M
in
Biological variation
,
Biomarkers
,
Cancer
2018
In the past decade, the search for circulating microRNA (miRNA) biomarkers has yielded numerous associations between miRNAs and different types of disease. However, many of these relations could not be replicated in subsequent studies under similar experimental conditions. Although this lack of replicability may be explained by the variation in experimental design and analysis methods, guidelines on the most appropriate design and analysis methods to study circulating miRNAs are scarce.
miRNA biomarker experiments generally consist of a discovery phase and a validation phase. In the discovery phase, typically hundreds of miRNAs are measured in parallel to identify candidate biomarkers. Because of the costs of such high-throughput experiments, the number of individuals included in those studies is often too small, which can easily lead to false positives and false negatives. In the validation phase, a small number of identified biomarker candidates are measured in a large cohort of cases and controls, generally by quantitative PCR (qPCR). Although qPCR is a sensitive method to measure miRNAs in the circulation, experimental design and qPCR data analysis remain challenging. Omitting some crucial steps in the design and analysis of the qPCR experiment or performing them incorrectly can cause serious biases, ultimately leading to false conclusions.
In this review, we aim to expose and discuss the most common sources of interstudy variation in miRNA research from a methodological point of view and to provide guidelines on how to perform these steps correctly to increase replicability of studies on circulating miRNAs.
Journal Article
Reproducibility of sublingual microcirculation parameters obtained from sidestream darkfield imaging
by
Zwinderman, Aeilko H.
,
Valerio, Luca
,
Pinto-Sietsma, Sara-Joan
in
Adult
,
Atherosclerosis
,
Biology and Life Sciences
2019
Changes in the microcirculation may be used as a surrogate outcome in studies on cardiovascular disease. We assessed the reliability characteristics of the sublingual microcirculation parameters Vascular Density (VD), Red Blood Cell Filling (RBCF), and Perfused Boundary Region (PBR) as obtained by sidestream darkfield imaging.
For each of the three parameters, the variance components of measurement, the Intraclass Correlation Coefficient (ICC), the Standard Error of Measurement, and the limits of agreement were estimated for the intra-rater setting (N = 50) and the inter-rater setting (N = 48). Subsequently, as a proof of concept, the reliability measures were used for a power analysis to design studies to evaluate the effect of acute stimuli-i.e. having a meal (N = 50) and cigarette smoking (N = 21) on the three parameters.
Reproducibility was poor for all three parameters. The intra-rater ICC for 2 measurements was 0.28 (95% CI: 0.04, 0.53) for the VD, 0.51 (95% CI: 0.27, 0.69) for the RBCF, and 0.33 (95% CI: 0.08-0.56) for the PBR. The standard errors of measurement and the limits of agreement for all three parameters were larger than most statistically significant intra-individual or inter-individual differences reported in previous studies. The proofs of concept showed that sample sizes in excess of 600 subjects are necessary to reach statistical significance for the observed effects of having a meal or smoking on VD and PBR.
The reliability of the three sublingual microcirculation parameters in their current form appears to be low and a large sample size is advisable for their use in conditions similar to those we describe.
Journal Article
The mechanistic overview of SARS-CoV-2 using angiotensin-converting enzyme 2 to enter the cell for replication: possible treatment options related to the renin–angiotensin system
by
Paul, Martin
,
Montijn, Roy
,
Singh, Sandeep
in
Angiotensin II - metabolism
,
Angiotensin II Type 1 Receptor Blockers - therapeutic use
,
Animals
2020
Abstract
The SARS-CoV-2 pandemic is a healthcare crisis caused by insufficient knowledge applicable to effectively combat the virus. Therefore, different scientific discovery strategies need to be connected, to generate a rational treatment which can be made available as rapidly as possible. This relies on a solid theoretical understanding of the mechanisms of SARS-CoV-2 infection and host responses, which is coupled to the practical experience of clinicians that are treating patients. Because SARS-CoV-2 enters the cell by binding to angiotensin-converting enzyme 2 (ACE2), targeting ACE2 to prevent such binding seems an obvious strategy to combat infection. However, ACE2 performs its functions outside the cell and was found to enter the cell only by angiotensin II type 1 receptor (AT1R)-induced endocytosis, after which ACE2 is destroyed. This means that preventing uptake of ACE2 into the cell by blocking AT1R would be a more logical approach to limit entry of SARS-CoV-2 into the cell. Since ACE2 plays an important protective role in maintaining key biological processes, treatments should not disrupt the functional capacity of ACE2, to counterbalance the negative effects of the infection. Based on known mechanisms and knowledge of the characteristics of SARS-CoV we propose the hypothesis that the immune system facilitates SARS-CoV-2 replication which disrupts immune regulatory mechanisms. The proposed mechanism by which SARS-CoV-2 causes disease immediately suggests a possible treatment, since the AT1R is a key player in this whole process. AT1R antagonists appear to be the ideal candidate for the treatment of SARS-CoV-2 infection. AT1R antagonists counterbalance the negative consequences of angiotesnin II and, in addition, they might even be involved in preventing the cellular uptake of the virus without interfering with ACE2 function. AT1R antagonists are widely available, cheap, and safe. Therefore, we propose to consider using AT1R antagonists in the treatment of SARS-CoV-2.
Journal Article
Sublingual endothelial glycocalyx and atherosclerosis. A cross-sectional study
by
Zwinderman, Aeilko H.
,
Valerio, Luca
,
Pinto-Sietsma, Sara-Joan
in
Adult
,
Aged
,
Anticholesteremic agents
2019
Damage to endothelial glycocalyx is thought to be an early marker of atherosclerosis and measuring reduced glycocalyx size clinically via the Perfused Boundary Region (PBR) may allow early detection of cardiovascular disease. However, the true value of the glycocalyx in estimating cardiovascular risk or detecting cardiovascular disease is uncertain. We therefore investigated whether small glycocalyx size is associated with cardiovascular risk or disease in a large multi-ethnic cohort.
In a multi-ethnic community-based sample (N = 6169, 42.4% male, mean age 43.6 ±13) we applied multiple imputation for missing data and used logistic regression and odds ratios to cross-sectionally investigate the relationship of small glycocalyx size as estimated by highest quartile of PBR with, on the one hand, classical risk factors for atherosclerosis including age, sex, diastolic and systolic blood pressure, LDL, HDL, triglycerides, BMI, diabetes, smoking status, and antihypertensive and lipid-lowering medication; on the other hand, prevalent cardiovascular disease. Analyses were additionally adjusted for ethnicity.
With PBR divided in quartiles, the highest PBR quartile (smallest glycocalyx size) as dependent variable was independently associated with female sex (OR for male versus female: 0.61, 95% CI: 0.53, 0.70) and diabetes (OR: 1.28, 95% CI: 1.03-1.59) in a model adjusted for all classical risk factors of atherosclerosis and for ethnicity. With regard to cardiovascular disease, no association was found between the smallest glycocalyx size as independent variable and overall cardiovascular disease, coronary heart disease and revascularization procedures, or stroke.
Small glycocalyx size as estimated by highest PBR is associated with female sex and diabetes, which do not completely reflect a high cardiovascular risk profile. At the same time, glycocalyx size is not associated with prevalent cardiovascular disease.
Journal Article
Depicting the composition of gut microbiota in a population with varied ethnic origins but shared geography
by
Bakker, Guido J.
,
Zwinderman, Aeilko H.
,
Pinto-Sietsma, Sara-Joan
in
631/326/2565/2134
,
692/308/174
,
Africa - epidemiology
2018
Trillions of microorganisms inhabit the human gut and are regarded as potential key factors for health
1
,
2
. Characteristics such as diet, lifestyle, or genetics can shape the composition of the gut microbiota
2
–
6
and are usually shared by individuals from comparable ethnic origin. So far, most studies assessing how ethnicity relates to the intestinal microbiota compared small groups living at separate geographical locations
7
–
10
. Using fecal 16S ribosomal RNA gene sequencing in 2,084 participants of the Healthy Life in an Urban Setting (HELIUS) study
11
,
12
, we show that individuals living in the same city tend to share similar gut microbiota characteristics with others of their ethnic background. Ethnicity contributed to explain the interindividual dissimilarities in gut microbiota composition, with three main poles primarily characterized by operational taxonomic units (OTUs) classified as
Prevotella
(Moroccans, Turks, Ghanaians),
Bacteroides
(African Surinamese, South-Asian Surinamese), and Clostridiales (Dutch). The Dutch exhibited the greatest gut microbiota α-diversity and the South-Asian Surinamese the smallest, with corresponding enrichment or depletion in numerous OTUs. Ethnic differences in α-diversity and interindividual dissimilarities were independent of metabolic health and only partly explained by ethnic-related characteristics including sociodemographic, lifestyle, or diet factors. Hence, the ethnic origin of individuals may be an important factor to consider in microbiome research and its potential future applications in ethnic-diverse societies.
Stool microbiota composition correlates with the ethnic backgrounds of people living in the same city, suggesting that geographical location and ethnicity have distinct effects on microbiota.
Journal Article
Primary Prevention of Atherosclerotic Cardiovascular Disease Fails in Young Individuals According to Recent Data in The Netherlands
by
Wottschel, Viktor
,
van de Wiel, Kayleigh M.
,
Crooijmans, Juliette J.
in
atherosclerotic disease
,
cardiovascular disease
,
Comorbidity
2026
Background: Atherosclerotic cardiovascular disease (ASCVD) is one of the most important causes of morbidity worldwide. Registries show an impressive decline in prevalent ASCVD morbidity over the last years. Whether this decline is due to the improvement in treatment options for ASCVD or whether we are also able to prevent first ASCVD events is still unknown. Methods: A nationally representative real-world data longitudinal prescription (LRx) database (IQVIA) was used over a period from 2008 to 2019. All patients ≥20 years were included from the moment they had been prescribed ASCVD medication. The primary outcome was the standardized incidence of first ASCVD events among men and women of different age groups. The secondary outcome of this study was to identify comorbidities in the year 2019. Results: The prescription data on 296.050 individuals were analyzed, and the results indicate the standardized cumulative incidence (%) among women of first ASCVD event prescriptions. This rise in incidence was most pronounced for young women (women 20–39 yr: + 109.46%). The comorbidity analysis indicated that, e.g., thyroid hormones were significantly more often prescribed in the young patients with a first ASCVD event than in those patients without ASCVD events. Conclusions: Prescriptions for the first ASCVD event increased over a period of 12 years among young women. This study suggests that although ASCVD as a whole has decreased over time, this does not seem to be the case for first ASCVD events and that young women are particularly affected.
Journal Article
Platelets in Patients with Premature Coronary Artery Disease Exhibit Upregulation of miRNA340 and miRNA624
by
Bakker, Annemieke
,
Pinto-Sietsma, Sara-Joan
,
de Ronde, Maurice W. J.
in
Adult
,
Arteriosclerosis
,
Atherosclerosis
2011
Coronary artery disease (CAD) is the leading cause of human morbidity and mortality worldwide, underscoring the need to improve diagnostic strategies. Platelets play a major role, not only in the process of acute thrombosis during plaque rupture, but also in the formation of atherosclerosis itself. MicroRNAs are endogenous small non-coding RNAs that control gene expression and are expressed in a tissue and disease-specific manner. Therefore they have been proposed to be useful biomarkers. It remains unknown whether differences in miRNA expression levels in platelets can be found between patients with premature CAD and healthy controls.
In this case-control study we measured relative expression levels of platelet miRNAs using microarrays from 12 patients with premature CAD and 12 age- and sex-matched healthy controls. Six platelet microRNAs were significantly upregulated (miR340*, miR451, miR454*, miR545:9.1. miR615-5p and miR624*) and one miRNA (miR1280) was significantly downregulated in patients with CAD as compared to healthy controls. To validate these results, we measured the expression levels of these candidate miRNAs by qRT-PCR in platelets of individuals from two independent cohorts; validation cohort I consisted of 40 patients with premature CAD and 40 healthy controls and validation cohort II consisted of 27 patients with artery disease and 40 healthy relatives. MiR340* and miR624* were confirmed to be upregulated in patients with CAD as compared to healthy controls in both validation cohorts.
Two miRNAs in platelets are significantly upregulated in patients with CAD as compared to healthy controls. Whether the two identified miRNAs can be used as biomarkers and whether they are cause or consequence of the disease remains to be elucidated in a larger prospective study.
Journal Article
Circulating MicroRNAs Characterizing Patients with Insufficient Coronary Collateral Artery Function
2015
Coronary collateral arteries function as natural bypasses in the event of coronary obstruction. The degree of collateral network development significantly impacts the outcome of patients after an acute myocardial infarction (AMI). MicroRNAs (miRNAs, miRs) have arisen as biomarkers to identify heterogeneous patients, as well as new therapeutic targets in cardiovascular disease. We sought to identify miRNAs that are differentially expressed in chronic total occlusion (CTO) patients with well or poorly developed collateral arteries.
Forty-one CTO patients undergoing coronary angiography and invasive assessment of their coronary collateralization were dichotomized based on their collateral flow index (CFI). After miRNA profiling was conducted on aortic plasma, four miRNAs were selected for validation by real-time quantitative reverse transcription polymerase chain reaction in patients with low (CFI<0.39) and high (CFI>0.39) collateral artery capacity. We confirmed significantly elevated levels of miR423-5p (p<0.05), miR10b (p<0.05), miR30d (p<0.05) and miR126 (p<0.001) in patients with insufficient collateral network development. We further demonstrated that each of these miRNAs could serve as circulating biomarkers to discriminate patients with low collateral capacity (p<0.01 for each miRNA). We also determined significantly greater expression of miR30d (p<0.05) and miR126 (p<0.001) in CTO patients relative to healthy controls.
The present study identifies differentially expressed miRNAs in patients with high versus low coronary collateral capacity. We have shown that these miRNAs can function as circulating biomarkers to discriminate between patients with insufficient or sufficient collateralization. This is the first study to identify miRNAs linked to coronary collateral vessel function in humans.
Journal Article