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van der Zande, H. J. P.

Publications and source records attributed to van der Zande, H. J. P..

4 recordsLinked to original sources

Weight cycling-induced hypothalamic and metabolic tissue immune remodeling is uncoupled from metabolic dysfunctions

BackgroundObesity-induced insulin resistance is associated with white adipose tissue (WAT) and liver inflammation, which are both mitigated by weight loss. However, most individuals undergoing weight loss will regain lost weight, resulting in weight cycling (WC), which may exacerbate metabolic dysfunctions. Here, we studied the immunometabolic impact of WC in mice. MethodsC57BL/6J mice were exposed to two cycles of weight gain and weight loss by alternating between low (LFD) and high-fat diet (HFD) feeding. Animals were sacrificed when WC mice were weight stable for 10 weeks upon weight loss (WC-lean) and after a subsequent exposure to weight regain for 10 weeks (WC-obese), and compared to mice persistently fed LFD (LFD-lean) or HFD (HFD-obese). ResultsBody weight stabilized at a higher level in WC-lean mice after two weight gain/loss cycles compared to LFD-lean controls. While insulin resistance, metabolic tissue inflammation, and hepatic steatosis normalized between the two groups of lean mice, WC-lean mice exhibited features of WAT dysfunction. In the hypothalamus, inflammatory microglia were less abundant in WC-lean mice compared to LFD-lean mice, but mean individual microglial cell volume was larger. WC-obese mice stabilized at slightly lower weight compared with HFD-obese controls. Intriguingly, WC-obese mice exhibited increased WAT macrophages and reduced WAT and liver effector T cells compared to HFD-obese mice, whereas energy intake, body composition, whole-body insulin resistance and hepatic steatosis were similar. ConclusionsOur results suggest that WC in mice differently impacts animals in the weight-stable lean and obese states. WC-lean mice display features of a novel body weight settling point, associated with hypothalamic inflammatory changes. However, metabolic dysfunctions were uncoupled from WC-induced metabolic tissue inflammation in WC-obese mice.

immunology↗

In-depth immunometabolic profiling by measuring single-cell protein translation inhibition via bioorthogonal noncanonical amino acid tagging (SCENITH-BONCAT)

MotivationExtracellular Flux (XF) analysis has been a key technique in immunometabolism research, measuring cellular oxygen consumption rate (OCR) and extracellular acidification rate (ECAR) to determine immune cell metabolic profiles. However, XF analysis has several limitations, including the need for purified adherent cells, relatively high cell numbers, and specialized equipment. Recently, a novel flow cytometry-based technique called SCENITH (Single Cell Energetic metabolism by profiling Translation inhibition) was introduced, which measures the inhibition of cellular protein synthesis as a proxy for metabolic activity in single cells. A limitation of this technique is its reliance on fluorescent staining of intracellular puromycin, a toxic antibiotic. To address this, we propose an alternative approach using biorthogonal noncanonical amino acid tagging (BONCAT) to measure protein synthesis. SummaryThe field of immunometabolism has revealed that cellular energy metabolism significantly contributes to immune cell function. Disturbances in immune cell metabolism have been associated with various diseases, including obesity, atherosclerosis, and cancer. To further advance immunometabolic research, developing novel methods to study the metabolism of immune cells in complex samples is essential. Here, we introduce CENCAT (Cellular Energetics through Non-Canonical Amino acid Tagging). This technique utilizes click-labeling of alkyne-bearing non-canonical amino acids (ncAAs) to measure protein synthesis inhibition as a proxy of metabolic activity. CENCAT successfully reproduced known metabolic signatures of immune cell activation. Specifically, LPS/IFN{gamma}-induced classical activation increased glycolytic capacity, and IL-4-induced alternative activation enhanced mitochondrial dependence in human primary macrophages. The assays applicability was further explored in more complex samples, including peripheral blood mononuclear cells (PBMCs) from healthy volunteers, which revealed diverse metabolic rewiring in immune cell subsets upon stimulation with different activators. Finally, CENCAT was used to analyze the cellular metabolism of murine tissue-resident immune cells from various organs. Principal component analysis (PCA) revealed tissue-specific clustering based on metabolic profiles, likely driven by microenvironmental priming of tissue-resident immune cells. In conclusion, CENCAT offers valuable insights into immune cell metabolic responses and presents a powerful platform for studying immune cell metabolism in complex samples and tissue-resident immune populations in both human and murine studies.

immunology↗

LKB1 signalling in dendritic cells controls whole-body metabolic homeostasis by limiting T helper 17 priming

Obesity-associated metaflammation drives the development of insulin resistance and type 2 diabetes, notably through modulating innate and adaptive immune cells in metabolic organs. The nutrient sensor liver kinase B1 (LKB1) has recently been shown to control cellular metabolism and T cell priming functions of dendritic cells (DCs). Here, we report that hepatic DCs from high-fat diet (HFD)-fed obese mice display increased LKB1 phosphorylation and that LKB1 deficiency in DCs (CD11c{Delta}LKB1) worsened HFD-driven hepatic steatosis, systemic insulin resistance and glucose intolerance. Loss of LKB1 in DCs was associated with increased cellular expression of Th17-polarizing cytokines and increased hepatic CD4+ IL-17A+ Th17 cells in HFD-fed mice. Importantly, IL-17A neutralization rescued metabolic perturbations in HFD-fed CD11c{Delta}LKB1 mice. Mechanistically, disrupted metabolic homeostasis was independent of the canonical LKB1-AMPK axis. Instead, we provide evidence for involvement of the AMPK-related salt-inducible kinase(s) in controlling Th17-polarizing cytokine expression in LKB1-deficient DCs. Altogether, our data reveal a key role for LKB1 signalling in DCs in protection against obesity-induced metabolic dysfunctions by limiting hepatic Th17 differentiation.

immunology↗

The helminth glycoprotein omega-1 improves metabolic homeostasis in obese mice through type-2 immunity-independent inhibition of food intake

Type 2 immunity plays an essential role in the maintenance of metabolic homeostasis and its disruption during obesity promotes meta-inflammation and insulin resistance. Infection with the helminth parasite Schistosoma mansoni and treatment with its soluble egg antigens (SEA) can induce a type 2 immune response in metabolic organs and improve insulin sensitivity and glucose tolerance in obese mice, yet a causal relationship remains unproven. Here, we investigated the effects and underlying mechanisms of the T2 ribonuclease omega-1 (ω1), one of the major S. mansoni immunomodulatory glycoproteins, on metabolic homeostasis. Male C57Bl6/J mice were fed a high-fat diet for 12 weeks followed by bi-weekly injection of SEA, ω1 or vehicle for 4 additional weeks. Whole-body metabolic homeostasis and energy expenditure were assessed by glucose/insulin tolerance tests and indirect calorimetry, respectively. Tissue-specific immune cell phenotypes were determined by flow cytometry. We show that treatment of obese mice with plant-produced recombinant ω1, harboring similar glycan motifs as present on the native molecule, decreased body fat mass and improved systemic insulin sensitivity and glucose tolerance in a time-and dose-dependent manner. This effect was associated with an increase in white adipose tissue (WAT) type 2 T helper cells, eosinophils and alternatively-activated macrophages, without affecting type 2 innate lymphoid cells. In contrast to SEA, the metabolic effects of ω1 were still observed in obese STAT6-deficient mice with impaired type 2 immunity, indicating that its metabolic effects are independent of the type 2 immune response. Instead, we found that ω1 inhibited food intake, without affecting locomotor activity, WAT thermogenic capacity or whole-body energy expenditure, an effect also occurring in leptin receptor-deficient obese and hyperphagic db/db mice. Altogether, we demonstrate that while the helminth glycoprotein ω1 can induce type 2 immunity, it improves whole-body metabolic homeostasis in obese mice by inhibiting food intake via a STAT6-independent mechanism.Author summary The obesity-induced chronic low-grade inflammation, notably in adipose tissue, contributes to insulin resistance and increased risk of type 2 diabetes. We have previously shown that infection with parasitic helminth worms was associated with protection against obesity-related metabolic dysfunctions both in mice and humans. We have also reported that treatment of obese mice with an extract of Schistosoma mansoni eggs (SEA) improves insulin sensitivity and glucose tolerance, a beneficial effect that was associated with a helminth-specific type 2 immune response in metabolic organs. Here, we studied the effects of omega-1 (ω1), a single immunomodulatory molecule from SEA, on metabolic health in obese mice, and investigated the role of the host immune response elicited. We found that ω1 induced a helminth-characteristic type 2 immune response in adipose tissue and improved both insulin sensitivity and glucose tolerance in obese mice. Yet, in contrast to SEA, ω1’s immunomodulatory properties were dispensable for its metabolic effects. Instead, we show that ω1 inhibited food intake, a feature accounting for most of the improvements in metabolic health. Together, our findings indicate that helminth molecules may improve metabolic health through multiple distinct mechanisms, and further characterization of such molecules could lead to new therapeutic strategies to combat obesity.List of abbreviationsAAMAlternatively activated macrophageALATAlanine aminotransferaseBATBrown adipose tissueDCDendritic cellEEEnergy expenditureGTTGlucose tolerance testHEKHuman embryonic kidneyHFDHigh-fat dietHOMA-IRHomeostatic model assessment of insulin resistanceIFN-γInterferon gammaILInterleukinILCInnate lymphoid cellITTInsulin tolerance testLBMLean body massLFDLow-fat dietNAFLDNon-alcoholic fatty liver diseaseNASHNon-alcoholic steatohepatitispLeX-ω1Recombinant omega-1 from LeX-glyco-engineered Nicotiana benthamiana plantsPMAPhorbol myristate acetatepWT-ω1Recombinant omega-1 from wild-type N. benthamiana plantsSEASchistosoma mansoni soluble egg antigensSTATSignal transducer and activator of transcriptionSVFStromal vascular fractionThT helperTNFTumor necrosis factorUCP1Uncoupling protein 1WATWhite adipose tissueWTWild-typeView Full Text

immunology↗