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Kooijman, S.

Publications and source records attributed to Kooijman, S..

6 recordsLinked to original sources

Exercise training at different intensities induces heat stress, disrupts barrier function and alters microbiota in the gut of mice

Exercise is generally beneficial for health but strenuous exercise can have detrimental effects on the gastrointestinal tract. The combination of ischemia and heat shock during exercise is a crucial contributor to intestinal epithelial damage. Growing evidence points towards an important regulatory role of gut microbes in intestinal homeostasis. Here, we characterize and compare the effects of moderate and vigorous exercise training on intestinal epithelial damage, stress response, inflammatory response, and gut microbiota alterations in mice and investigate the mechanisms underlying exercise-induced intestinal injury. Exercise training for six weeks caused heat stress in the intestine, resulting in the disruption of the intestinal epithelial barrier and local inflammation. This was characterized by increased colonic HSP-70 and HSF-1 protein expression, increased epithelial permeability, decreased colonic expression of tight junction proteins ZO-1 and occludin and intestinal morphological changes. Daily moderate exercise training caused hereby more severe injury than vigorous training on alternating days. Furthermore, exercise training altered the gut microbiota profile. The abundance of Lactobacillaceae was reduced, potentially contributing to the deteriorated intestinal status, while the abundance of short-chain fatty acid-producing Lachnospiraceae was increased, especially following vigorous training. This increase in short-chain fatty acid-producing bacteria following vigorous training possibly counteracted the impairment of the intestinal barrier function. In summary, exercise disrupts the intestinal barrier function, with vigorous exercise training with intermittent rest days being less damaging than daily moderate exercise training.

physiology↗

Short-term Pre-operative Methionine Restriction Induces Browning of Perivascular Adipose Tissue and Improves Vein Graft Remodeling in Mice

Short-term preoperative methionine restriction (MetR) shows promise as a translatable strategy to modulate the bodys response to surgical injury. Its application, however, to improve post-interventional vascular remodeling remains underexplored. Here, we find that MetR protects from arterial intimal hyperplasia in a focal stenosis model and adverse vascular remodeling after vein graft surgery. RNA sequencing reveals that MetR enhances the brown adipose tissue phenotype in arterial perivascular adipose tissue (PVAT) and induces it in venous PVAT. Specifically, PPAR- was highly upregulated in PVAT-adipocytes. Furthermore, MetR dampens the post-operative pro-inflammatory response to surgery in PVAT-macrophages in vivo and in vitro. This study shows for the first time that the detrimental effects of dysfunctional PVAT on vascular remodeling can be reversed by MetR, and identifies pathways involved in browning of PVAT. Furthermore, we demonstrate the potential of short-term pre-operative MetR as a simple intervention to ameliorate vascular remodeling after vascular surgery. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=109 SRC="FIGDIR/small/565269v1_ufig1.gif" ALT="Figure 1"> View larger version (38K): org.highwire.dtl.DTLVardef@112f51aorg.highwire.dtl.DTLVardef@1998bd8org.highwire.dtl.DTLVardef@1ac5046org.highwire.dtl.DTLVardef@1ca4c87_HPS_FORMAT_FIGEXP M_FIG C_FIG

systems biology↗

Time to run: Late rather than early exercise training in mice remodels the gut microbiome and reduces atherosclerosis development

The metabolic and inflammatory processes that are implicated in the development of cardiovascular diseases are under control of the biological clock. While skeletal muscle function exhibits circadian rhythms, it is unclear to what extent the beneficial health effects of exercise are restricted to unique time windows. We aimed to study whether the timing of exercise training differentially modulates the development of atherosclerosis and elucidate underlying mechanisms. We endurance-trained atherosclerosis-prone female APOE*3-Leiden.CETP mice fed a Western-type diet, a well-established human-like model for cardiometabolic diseases, for one hour five times a week for four weeks either in their early or in their late active phase on a treadmill. We monitored metabolic parameters, the development of atherosclerotic lesions in the aortic root and assessed the composition of the gut microbiota. Late, but not early, exercise training reduced fat mass by 19% and the size of early-stage atherosclerotic lesions by as much as 29% compared to sedentary animals. No correlation between cholesterol exposure and lesion size was evident, as no differences in plasma lipid levels were observed, but circulating levels of the pro-inflammatory markers ICAM-1 and VCAM-1 were reduced with late exercise. Strikingly, we observed a time-of-day-dependent effect of exercise training on the composition of the gut microbiota as only late training increased the abundance of gut bacteria producing short-chain fatty acids with proposed anti-inflammatory properties. Together, these findings indicate that timing is a critical factor to the beneficial anti-atherosclerotic effects of exercise with a great potential to further optimize training recommendations for patients.

physiology↗

Cold exposure induces dynamic changes in circulating triacylglycerol species, which is dependent on intracellular lipolysis: a randomized cross-over trial

BackgroundThe application of cold exposure has emerged as an approach to enhance whole-body lipid catabolism. The global effect of cold exposure on the lipidome in humans has been reported with mixed results depending on intensity and duration of cold. MethodsThis secondary study was based on data from a previous randomized cross-over trial (ClinicalTrials.gov ID: NCT03012113). We performed sequential lipidomic profiling in serum during 120 min cold exposure of human volunteers. Next, the intracellular lipolysis was blocked in mice using a small-molecule inhibitor of adipose triglyceride lipase (ATGL; Atglistatin), and were exposed to cold for a similar duration. The quantitative lipidomic profiling was assessed in-depth using the Lipidyzer platform. FindingsCold exposure gradually increased circulating free fatty acids reaching a maximum at 60 min, and transiently decreased total triacylglycerols (TAGs) only at 30 min. A broad range of TAG species was initially decreased, in particular unsaturated and polyunsaturated TAG species with [≤]5 double bonds, while after 120 min a significant increase was observed for polyunsaturated TAG species with [≥]6 double bonds. The mechanistic study in mice revealed that the cold-induced increase in polyunsaturated TAGs was largely prevented by blocking adipose triglyceride lipase. InterpretationWe interpret these findings as that cold exposure feeds thermogenic tissues with TAG-derived fatty acids for combustion, resulting in a decrease of circulating TAG species, followed by increased hepatic production of polyunsaturated TAG species induced by liberation of free fatty acids stemming from adipose tissue. Research in ContextO_ST_ABSEvidence before this studyC_ST_ABSCold exposure has emerged as a novel non-pharmacological strategy to enhance whole-body lipid catabolism, to improve lipid homeostasis and ultimately cardiometabolic health. In mice, cold exposure accelerates the clearance of triacylglycerol (TAG)-rich lipoproteins from the circulation, reducing circulating TAGs. In humans however, the effect of cold exposure on whole-body TAG metabolism remained thus far controversial, as mixed results are reported depending on intensity and duration of cold. Added value of this studyHere, we performed sequential lipidomic profiling in serum during 120 min cold exposure of human volunteers. We show that cold exposure gradually increases circulating free fatty acids and transiently decreases total TAGs after 30 min, accompanied with a dynamic change in circulating TAGs as dependent on their saturation status and length. Specifically, cold exposure decreases a broad range of more saturated and shorter TAG species, while after 90-120 min polyunsaturated TAG species with [≥]6 double bonds start to increase. Subsequently, we performed a mechanistic study in mice, in which we show that the cold-induced increase in polyunsaturated TAGs is largely prevented when blocking intracellular lipolysis. Implications of all the available evidenceOur findings describe a mechanism by which cold exposure provides thermogenic tissues with TAG-derived fatty acids for combustion. At the same time, cold exposure increases lipolysis in white fat to drive hepatic TAG production to further feed thermogenic tissues. For the first time, these results show that the TAG lowering effect of cold exposure as observed in mice can be recapitulated in humans, which warrants further studies on the beneficial effects of cold exposure on accelerating lipid metabolism to improve cardiometabolic health.

physiology↗

Aging selectively dampens oscillation of lipid abundance in white and brown adipose tissue

Lipid metabolism is under the control of the circadian system and circadian dysregulation has been linked to obesity and dyslipidemia. These factors and outcomes have also been associated to, or affected by, the process of aging. Here, we investigated whether murine white (WAT) and brown (BAT) adipose tissue lipids exhibit rhythmicity and if this is affected by aging. To this end, we have measured the 24 hour lipid profiles of WAT and BAT using a global lipidomics analysis of >1100 lipids. We observed rhythmicity in nearly all lipid classes including glycerolipids, glycerophospholipids, sterol lipids and sphingolipids. Overall, ~22% of the analyzed lipids were considered rhythmic in WAT and BAT. Despite a general accumulation of lipids upon aging the fraction of oscillating lipids decreased in both tissues to 14% and 18%, respectively. Diurnal profiles of lipids in BAT appeared to depend on the lipid acyl chain length and this specific regulation was lost in aged mice. Our study revealed how aging affects the rhythmicity of lipid metabolism and could contribute to the quest for targets that improve diurnal lipid homeostasis to maintain cardiometabolic health during aging.

biochemistry↗

Associations between outdoor temperature and bright sunlight with metabolites in two population-based European cohorts

Context: Outdoor temperature and bright sunlight may directly and/or indirectly modulate systemic metabolism. Objective: We assessed the associations between outdoor temperature and bright sunlight duration with metabolomics. Design: meta-analysis of two cross-sectional studies. Setting: Two population-based European cohort studies. Patients or other participants: Non-diabetic individuals from the Oxford BioBank (OBB; N=6,368; mean age 47.0 years, males 44%) and the Netherlands Epidemiology of Obesity (NEO; N=5,916; mean age 55.6 years, males 43%) studies. Intervention(s): Data on mean outdoor bright sunlight and temperature collected from local weather stations in the week prior to blood sampling. Main Outcome Measure(s): Serum levels of 148 metabolites measured using NMR spectroscopy, including 14 lipoprotein subclasses. Statistical analyses: Multivariable linear regression analyses adjusted for age, sex, body mass index, season and either outdoor temperature or bright sunlight. Summary statistics from the OBB and NEO cohorts were combined using fixed-effect meta-analyses. Results: A higher mean outdoor temperature was associated with increased concentrations of lipoprotein (sub)particles and certain amino acids such as phenylalanine and leucine. In contrast, longer mean hours of bright sunlight were specifically associated with lower concentrations of very low density lipoprotein (sub)particles. The direction of effects was consistent between the OBB and NEO, although effect sizes were generally larger in the OBB. Conclusions: Increased bright sunlight duration is associated with an improved metabolic profile whilst higher outdoor temperature may adversely impact cardiometabolic health.

physiology↗