CD36 deficiency blunts effects of diet on regulatory T cells in murine gonadal adipose tissue and mesenteric lymph nodes

The effect of cluster of differentiation (CD)36 on regulatory T cells (Treg) was investigated in gonadal (GN) adipose tissues and mesenteric lymph nodes (MLN) of wild-type (WT) and CD36 deficient (CD36−/−) mice kept on standard fat (SFD, lean) or on high fat diet (HFD, obese). GN adipose tissue mass was smaller, but MLN size larger for obese CD36−/− versus obese WT mice. Overall, the reduction of Treg cells in GN adipose tissue and MLN after a HFD is much more prominent in WT than CD36−/− mice. Moreover, CD36−/− mice may be protected against obesity-related chronic inflammation.publisher: Elsevier articletitle: CD36 deficiency blunts effects of diet on regulatory T cells in murine gonadal adipose tissue and mesenteric lymph nodes journaltitle: Cellular Immunology articlelink: http://dx.doi.org/10.1016/j.cellimm.2015.08.006 content_type: article copyright: Copyright © 2015 Elsevier Inc. All rights reserved.status: publishe

The Anti-Adipogenic Potential of COUP-TFII Is Mediated by Downregulation of the Notch Target Gene Hey1

BACKGROUND: Chicken ovalbumin upstream promoter transcription factor II (COUP-TFII) belongs to the steroid/thyroid hormone receptor superfamily and may contribute to the pathogenesis of obesity. It has not conclusively been established, however, whether its role is pro- or anti-adipogenic. METHODS AND RESULTS: Gene silencing of Coup-tfII in 3T3-F442A preadipocytes resulted in enhanced differentiation into mature adipocytes. This was associated with upregulation of the Notch signaling target gene Hey1. A functional role of Hey1 was confirmed by gene silencing in 3T3-F442A preadipocytes, resulting in impaired differentiation. In vivo, de novo fat pad formation in NUDE mice was significantly stimulated following injection of preadipocytes with Coup-tfII gene silencing, but impaired with Hey1 gene silencing. Moreover, expression of Coup-tfII was lower and that of Hey1 higher in isolated adipocytes of obese as compared to lean adipose tissue. CONCLUSIONS: These in vitro and in vivo data support an anti-adipogenic role of COUP-TFII via downregulating the Notch signaling target gene Hey1.status: publishe

Protein-Polyelectrolyte complexes as versatile building blocks for the surface immobilization of proteins in layer-by-layer assemblies

ORAL presentation at the 31st Conference of the European Society for Biomaterials (ESB2021) together with 43rd Annual Congress of the Iberian Society of Biomechanics and Biomaterials (SIBB

Adiposity and metabolic health in mice deficient in intestinal alkaline phosphatase

Intestinal alkaline phosphatase 3 (AKP3) is an enzyme that was reported to play a role in lipid metabolism and to prevent high fat diet-induced metabolic syndrome in mice. To investigate a potential functional role of AKP3 in diet-induced adiposity and metabolic health, we have kept male and female wild-type or AKP3 deficient mice on a high fat diet for 15 weeks to induce obesity and compared those with mice kept on standard fat diet. Body weight as well as adipose tissue mass were statistically significantly higher upon high fat diet feeding for mice of both genders and genotypes. Female mice of either genotype kept on high fat diet gained less weight, resulting in smaller adipose tissue depots with smaller adipocytes. However, AKP3 deficiency had no significant effect on body weight gain or adipose tissue mass and did not affect adipocyte size or density. Gene expression analysis revealed no effect of the genotype on inflammatory parameters in adipose tissue, except for tumor necrosis factor alpha, which was higher in mesenteric adipose tissue of female obese mice. Plasma glucose and insulin levels were also not affected in obese AKP3 deficient mice. Overall, our data do not support a functional role of AKP3 in adipose tissue development, or insulin sensitivity.status: publishe

Expression of <i>Coup-tfII</i> and <i>Hey1</i> in adipose tissue and isolated cell fractions.

<p>Expression of <i>Coup-tfII</i> (A) or <i>Hey1</i> (B) in gonadal (GN) and subcutaneous (SC) adipose tissues, as well as in isolated adipocytes and stromal vascular fractions (SVF) and in microvascular endothelial cells (MEC) derived from SC and GN adipose tissues obtained from obese mice, is shown relative to samples from lean mice (dotted line). Data are means ± SEM of at least 4 samples; * p < 0.05, ** p < 0.01, *** p < 0.001.</p

Body weight and fat depots of NUDE mice injected with 3T3-F442A preadipocytes with or without Hey1 gene silencing and kept on HFD for 4 weeks.

<p>Data are means ± SEM of n experiments. SC, subcutaneous; GN, gonadal; Hey1 kd (Hey1 gene silencing).</p

Advanced-age C57BL/6JRj mice do not develop obesity upon western-type diet exposure

Obesity has become a global health-threat for every age group. It is well known that young mice (10-12 weeks of age) fed a western-type diet (WD) become obese and develop higher cholesterol levels and liver steatosis whereas insulin sensitivity is reduced. Less is known, however, about the effect of a WD on advanced-age mice. Therefore, 10 week-old (young) and 22 month-old (advanced-age), male C57BL/6JRj mice were kept on either a WD or a control diet (SFD) for 15 weeks. In contrast to young mice, advanced-age mice on WD did not show a higher body weight or adipose tissue (AT)-masses, suggesting a protection against diet-induced obesity. Furthermore, plasma adiponectin and leptin levels were not affected upon WD-feeding. A WD, however, did induce more hepatic lipid accumulation as well as increased hepatic expression of the macrophage marker F4/80, in advanced-age mice. There were no significant differences in mRNA levels of uncoupling protein-1 or F4/80 in brown AT (BAT) or of several intestinal integrity markers in colon suggesting that the protection against obesity is not due to excessive BAT or to impaired intestinal absorption of fat. Thus, advanced-age mice, in contrast to their younger counterparts, appeared to be protected against diet-induced obesity.status: publishe

Effect of <i>Coup-tfII</i> gene silencing on <i>in vitro</i> differentiation of 3T3-F442A preadipocytes.

<p>(A) Western blotting of COUP-TFII protein in extracts of cells without (control) or with (clone #1 and <i>#2 CouptfII kd</i>) gene silencing; lane M represents the protein marker (50 kDa) and Pos represents a positive control. (B) Time course of <i>Coup-tfII</i> expression during differentiation without (⚫, black circles) or with (△, open triangles) knockdown (kd). (C-D) Oil Red O staining (C) and quantification; OD at 490 nm (D) at day 12 of differentiation. (E-H) Time course of expression of <i>Pref-1</i> (E), <i>PPAR-γ</i> (F), <i>CD36</i> (G) and <i>GLUT4</i> (H) during differentiation without (⚫, black circles) or with (△, open triangles) gene silencing. (I) Time course of <i>Hey1</i> expression without (⚫, black circles) or with (△, open triangles) <i>Coup-tfII</i> knockdown (kd). (J) Correlation between expression (delta CT levels) of <i>Coup-tfII</i> and <i>Hey1</i> with or without <i>Coup-tfII</i> knockdown. (K-M) Time course of expression of C/EBPα (K), <i>C/EBPβ</i> (L) and <i>C/EBPδ</i> (M) during differentiation without (⚫, black circles) or with (△, open triangles) gene silencing. Data are means ± SEM of 3 independent experiments; * p < 0.05; ** p<0.01; *** p<0.001; **** p<0.0001 versus control. The scale bar in panel C corresponds to 100 μm</p

Body weight and fat depots of NUDE mice injected with 3T3-F442A preadipocytes with or without COUP-TFII gene silencing and kept on HFD for 4 weeks.

<p>Data are means ± SEM of n experiments. SC, subcutaneous; GN, gonadal; COUP-TFII kd (COUP-TFII gene silencing).</p

Layer-by-Layer Nanoarchitectonics Using Protein–Polyelectrolyte Complexes toward a Generalizable Tool for Protein Surface Immobilization

Layer-by-layer (LbL) self-assembly is an attractive method for the immobilization of macromolecules at interfaces. Integrating proteins in LbL thin films is however challenging due to their polyampholyte nature. Recently, we developed a method to integrate lysozyme into multilayers using protein−polyelectrolytes complexes (PPCs). In this work, we extended this method to a wide range of protein−polyelectrolyte combinations. We demonstrated the robustness and versatility of PPCs as building blocks. LL-37, insulin, lysozyme, and glucose oxidase were complexed with alginate, poly(styrenesulfonate), heparin, and poly(allylamine hydrochloride). The resulting PPCs were then LbL self-assembled with chitosan, PAH, and heparin. We demonstrated that multilayers built with PPCs are thicker compared to the LbL selfassembly of bare protein molecules. This is attributed to the higher mass of protein in the multilayers and/or the more hydrated state of the assemblies. PPCs enabled the self-assembly of proteins that could otherwise not be LbL assembled with a PE or with another protein. Furthermore, the results also show that LbL with PPCs enabled the construction of multilayers combining different proteins, highlighting the formation of multifunctional films. Importantly, we show that the adsorption behavior and thus the multilayer growth strongly depend on the nature of the protein and polyelectrolyte used. In this work, we elaborated a rationale to help and guide the use of PPCs for protein LbL assembly. It will therefore be beneficial to the many scientific communities willing to modify interfaces with hard-to-immobilize proteins and peptides