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Mulders-Manders, C. M.

Publications and source records attributed to Mulders-Manders, C. M..

2 recordsLinked to original sources

Low-grade inflammation in obesity causes low-effort food choice

Inflammation relates to decreased effortful behaviour and altered effort-related responses in brain regions, such as the dorsomedial prefrontal cortex (dmPFC). Inflammation is prevalent in obesity, but its effects on effortful versus more convenient food choices are unknown. We investigated the role of low-grade inflammation in effortful food choice using functional MRI in a cross-sectional study (n=150 women, BMI>27 kg/m{superscript 2}) and a 12-week randomized controlled trial (n=59 women, BMI>30 kg/m{superscript 2}, CRP>3 mg/L; colchicine 0.5 mg/d vs. placebo). Inflammation was related to less high-effort choices (OR=0.27, p=0.004) and higher effort-related dmPFC signal ({beta}=0.23, p=0.025, Rpartial{superscript 2}=0.039), and mediated the association between BMI and dmPFC signal. Colchicine decreased systemic inflammation (i.e. INFLA-score) as expected ({beta}=-0.10 SD, p<0.001, Rpartial{superscript 2}=0.030), increased high-effort choices (OR=1.32, p=0.044), and marginally decreased effort-related dmPFC signal ({beta}=-0.13, p=0.053, Rpartial{superscript 2}=0.037). These findings show a causal role for inflammation in choosing convenience foods in obesity via increased effort aversion and associated dmPFC processing.

neuroscience↗

Increased core body temperature exacerbates defective protein prenylation in mouse avatars of mevalonate kinase deficiency

Mevalonate kinase deficiency (MKD) is caused by biallelic loss-of-function mutations in MVK, leading to recurrent fevers and systemic inflammation. We describe new mouse avatars of MKD bearing p.Val377Ile (the commonest variant) or deletions in Mvk. Compound heterozygous mice recapitulated the biochemical phenotype of MKD, with build-up of unprenylated GTPases and increased plasma mevalonic acid. Mice with different deficiencies in mevalonate kinase revealed new insights into the genotype-phenotype relationship and mirrored the variability in the prenylation defect in human MKD, with p.V377I homozygous mice having a milder phenotype than compound heterozygous animals. The inflammatory response to LPS was enhanced in compound heterozygous mice in vivo and elevated serum interleukin-1{beta} was abrogated by NLRP3 inflammasome inhibition. Increased temperature dramatically but reversibly exacerbated the deficit in the mevalonate pathway and defective prenylation in vitro and in vivo, highlighting increased body temperature as a likely trigger of inflammatory flares and an additional potential target for future therapeutic approaches.

physiology↗