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Balaz M, Wolfrum C. Statins: benefits and risks revisited. Aging (Albany NY) 2019; 11:4300-4302. [PMID: 31303605 PMCID: PMC6660028 DOI: 10.18632/aging.102056] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2018] [Accepted: 06/23/2019] [Indexed: 01/13/2023]
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Banhos Danneskiold-Samsøe N, Sonne SB, Larsen JM, Hansen AN, Fjære E, Isidor MS, Petersen S, Henningsen J, Severi I, Sartini L, Schober Y, Wolf J, Nockher WA, Wolfrum C, Cinti S, Sina C, Hansen JB, Madsen L, Brix S, Kristiansen K. Overexpression of cyclooxygenase-2 in adipocytes reduces fat accumulation in inguinal white adipose tissue and hepatic steatosis in high-fat fed mice. Sci Rep 2019; 9:8979. [PMID: 31222118 PMCID: PMC6586826 DOI: 10.1038/s41598-019-45062-w] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Accepted: 05/30/2019] [Indexed: 12/16/2022] Open
Abstract
Cyclooxygenases are known as important regulators of metabolism and immune processes via conversion of C20 fatty acids into various regulatory lipid mediators, and cyclooxygenase activity has been implicated in browning of white adipose tissues. We generated transgenic (TG) C57BL/6 mice expressing the Ptgs2 gene encoding cyclooxygenase-2 (COX-2) in mature adipocytes. TG mice fed a high-fat diet displayed marginally lower weight gain with less hepatic steatosis and a slight improvement in insulin sensitivity, but no difference in glucose tolerance. Compared to littermate wildtype mice, TG mice selectively reduced inguinal white adipose tissue (iWAT) mass and fat cell size, whereas the epididymal (eWAT) fat depot remained unchanged. The changes in iWAT were accompanied by increased levels of specific COX-derived lipid mediators and increased mRNA levels of interleukin-33, interleukin-4 and arginase-1, but not increased expression of uncoupling protein 1 or increased energy expenditure. Epididymal WAT (eWAT) in TG mice exhibited few changes except from increased infiltration with eosinophils. Our findings suggest a role for COX-2-derived lipid mediators from adipocytes in mediating type 2 immunity cues in subcutaneous WAT associated with decreased hepatic steatosis, but with no accompanying induction of browning and increased energy expenditure.
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Abstract
Marrow adipose tissue (MAT) is a specialized adipose tissue with endocrine function found in bone marrow. In this issue of Cell Stem Cell, Ambrosi et al. (2017) identify a stem cell population in the bone marrow that can give rise to both osteogenic and adipogenic MAT precursors and is regulated by diet and aging and affects bone functionality.
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Sun W, von Meyenn F, Peleg‐Raibstein D, Wolfrum C. Environmental and Nutritional Effects Regulating Adipose Tissue Function and Metabolism Across Generations. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2019; 6:1900275. [PMID: 31179229 PMCID: PMC6548959 DOI: 10.1002/advs.201900275] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2019] [Revised: 03/21/2019] [Indexed: 05/12/2023]
Abstract
The unabated rise in obesity prevalence during the last 40 years has spurred substantial interest in understanding the reasons for this epidemic. Studies in mice and humans have demonstrated that obesity is a highly heritable disease; however genetic variations within specific populations have so far not been able to explain this phenomenon to its full extent. Recent work has demonstrated that environmental cues can be sensed by an organism to elicit lasting changes, which in turn can affect systemic energy metabolism by different epigenetic mechanisms such as changes in small noncoding RNA expression, DNA methylation patterns, as well as histone modifications. These changes can directly modulate cellular function in response to environmental cues, however research during the last decade has demonstrated that some of these modifications might be transmitted to subsequent generations, thus modulating energy metabolism of the progeny in an inter- as well as transgenerational manner. In this context, adipose tissue has become a focus of research due to its plasticity, which allows the formation of energy storing (white) as well as energy wasting (brown/brite/beige) cells within the same depot. In this Review, the effects of environmental induced obesity with a particular focus on adipose tissue are discussed.
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Chen W, Schwalie PC, Pankevich EV, Gubelmann C, Raghav SK, Dainese R, Cassano M, Imbeault M, Jang SM, Russeil J, Delessa T, Duc J, Trono D, Wolfrum C, Deplancke B. ZFP30 promotes adipogenesis through the KAP1-mediated activation of a retrotransposon-derived Pparg2 enhancer. Nat Commun 2019; 10:1809. [PMID: 31000713 PMCID: PMC6472429 DOI: 10.1038/s41467-019-09803-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Accepted: 03/29/2019] [Indexed: 12/15/2022] Open
Abstract
Krüppel-associated box zinc finger proteins (KZFPs) constitute the largest family of mammalian transcription factors, but most remain completely uncharacterized. While initially proposed to primarily repress transposable elements, recent reports have revealed that KFZPs contribute to a wide variety of other biological processes. Using murine and human in vitro and in vivo models, we demonstrate here that one poorly studied KZFP, ZFP30, promotes adipogenesis by directly targeting and activating a retrotransposon-derived Pparg2 enhancer. Through mechanistic studies, we further show that ZFP30 recruits the co-regulator KRAB-associated protein 1 (KAP1), which, surprisingly, acts as a ZFP30 co-activator in this adipogenic context. Our findings provide an understanding of both adipogenic and KZFP-KAP1 complex-mediated gene regulation, showing that the KZFP-KAP1 axis can also function in a non-repressive manner.
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81
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Balaz M, Becker AS, Balazova L, Straub L, Müller J, Gashi G, Maushart CI, Sun W, Dong H, Moser C, Horvath C, Efthymiou V, Rachamin Y, Modica S, Zellweger C, Bacanovic S, Stefanicka P, Varga L, Ukropcova B, Profant M, Opitz L, Amri EZ, Akula MK, Bergo M, Ukropec J, Falk C, Zamboni N, Betz MJ, Burger IA, Wolfrum C. Inhibition of Mevalonate Pathway Prevents Adipocyte Browning in Mice and Men by Affecting Protein Prenylation. Cell Metab 2019; 29:901-916.e8. [PMID: 30581121 DOI: 10.1016/j.cmet.2018.11.017] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/14/2018] [Revised: 10/15/2018] [Accepted: 11/27/2018] [Indexed: 01/10/2023]
Abstract
Recent research focusing on brown adipose tissue (BAT) function emphasizes its importance in systemic metabolic homeostasis. We show here that genetic and pharmacological inhibition of the mevalonate pathway leads to reduced human and mouse brown adipocyte function in vitro and impaired adipose tissue browning in vivo. A retrospective analysis of a large patient cohort suggests an inverse correlation between statin use and active BAT in humans, while we show in a prospective clinical trial that fluvastatin reduces thermogenic gene expression in human BAT. We identify geranylgeranyl pyrophosphate as the key mevalonate pathway intermediate driving adipocyte browning in vitro and in vivo, whose effects are mediated by geranylgeranyltransferases (GGTases), enzymes catalyzing geranylgeranylation of small GTP-binding proteins, thereby regulating YAP1/TAZ signaling through F-actin modulation. Conversely, adipocyte-specific ablation of GGTase I leads to impaired adipocyte browning, reduced energy expenditure, and glucose intolerance under obesogenic conditions, highlighting the importance of this pathway in modulating brown adipocyte functionality and systemic metabolism.
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Sun W, Dong H, Becker AS, Dapito DH, Modica S, Grandl G, Opitz L, Efthymiou V, Straub LG, Sarker G, Balaz M, Balazova L, Perdikari A, Kiehlmann E, Bacanovic S, Zellweger C, Peleg-Raibstein D, Pelczar P, Reik W, Burger IA, von Meyenn F, Wolfrum C. Publisher Correction: Cold-induced epigenetic programming of the sperm enhances brown adipose tissue activity in the offspring. Nat Med 2018; 24:1777. [PMID: 30087436 DOI: 10.1038/s41591-018-0163-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
In the version of this article originally published, the bars in the mean temperature graph in Fig. 1a were incorrectly aligned. The left-most bar should have been aligned with the Apr label on the projected month of conception axis. The error has been corrected in the print, PDF and HTML versions of this article.
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Wolfrum C, Kiehlmann E, Pelczar P. TRPC1 regulates brown adipose tissue activity in a PPARγ-dependent manner. Am J Physiol Endocrinol Metab 2018; 315:E825-E832. [PMID: 29989850 DOI: 10.1152/ajpendo.00170.2017] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Brown adipose tissue (BAT) has the unique ability to convert energy stored in the form of triglycerides into heat. This property makes BAT a target tissue to increase energy expenditure and improve systemic metabolic control. TRPC1 is a founding member of the TRP protein family that also includes several temperature sensitive channels. We show that TRPC1 is highly expressed in all adipocyte depots including BAT and that Trpc1-deficient mice are prone to weight gain and manifest reduced metabolic control. We also demonstrate that knockdown of TRPC1 in cultured brown adipocytes leads to a downregulation of several metabolic genes, including UCP1 and PPARγ, as well as upregulation of a BAT-specific thermosensitive channel TRPV2, ultimately resulting in impaired respiratory function. We also show that TRPC1 is a possible target of PPARγ, suggesting that TRPC1 is a downstream component of a mechanism that translates metabolic or environmental stimuli into output in the form of BAT activity. Better understanding of the possible role of TRPC1 and other TRP channels in body temperature regulation and BAT function may help us to develop obesity therapies based on BAT activation.
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Sarker G, Berrens R, von Arx J, Pelczar P, Reik W, Wolfrum C, Peleg-Raibstein D. Transgenerational transmission of hedonic behaviors and metabolic phenotypes induced by maternal overnutrition. Transl Psychiatry 2018; 8:195. [PMID: 30315171 PMCID: PMC6185972 DOI: 10.1038/s41398-018-0243-2] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/17/2017] [Revised: 02/18/2018] [Accepted: 04/15/2018] [Indexed: 12/22/2022] Open
Abstract
Maternal overnutrition has been associated with increased susceptibility to develop obesity and neurological disorders later in life. Most epidemiological as well as experimental studies have focused on the metabolic consequences across generations following an early developmental nutritional insult. Recently, it has been shown that maternal high-fat diet (HFD) affects third-generation female body mass via the paternal lineage. We showed here that the offspring born to HFD ancestors displayed addictive-like behaviors as well as obesity and insulin resistance up to the third generation in the absence of any further exposure to HFD. These findings, implicate that the male germ line is a major player in transferring phenotypic traits. These behavioral and physiological alterations were paralleled by reduced striatal dopamine levels and increased dopamine 2 receptor density. Interestingly, by the third generation a clear gender segregation emerged, where females showed addictive-like behaviors while male HFD offspring showed an obesogenic phenotype. However, methylome profiling of F1 and F2 sperm revealed no significant difference between the offspring groups, suggesting that the sperm methylome might not be the major carrier for the transmission of the phenotypes observed in our mouse model. Together, our study for the first time demonstrates that maternal HFD insult causes sustained alterations of the mesolimbic dopaminergic system suggestive of a predisposition to develop obesity and addictive-like behaviors across multiple generations.
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85
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Grandl G, Straub L, Rudigier C, Arnold M, Wueest S, Konrad D, Wolfrum C. Short-term feeding of a ketogenic diet induces more severe hepatic insulin resistance than an obesogenic high-fat diet. J Physiol 2018; 596:4597-4609. [PMID: 30089335 PMCID: PMC6166091 DOI: 10.1113/jp275173] [Citation(s) in RCA: 62] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2018] [Accepted: 06/18/2018] [Indexed: 11/25/2022] Open
Abstract
KEY POINTS A ketogenic diet is known to lead to weight loss and is considered metabolically healthy; however there are conflicting reports on its effect on hepatic insulin sensitivity. KD fed animals appear metabolically healthy in the fasted state after 3 days of dietary challenge, whereas obesogenic high-fat diet (HFD) fed animals show elevated insulin levels. A glucose challenge reveals that both KD and HFD fed animals are glucose intolerant. Glucose intolerance correlates with increased lipid oxidation and lower respiratory exchange ratio (RER); however, all animals respond to glucose injection with an increase in RER. Hyperinsulinaemic-euglycaemic clamps with double tracer show that the effect of KD is a result of hepatic insulin resistance and increased glucose output but not impaired glucose clearance or tissue glucose uptake in other tissues. ABSTRACT Despite being a relevant healthcare issue and heavily investigated, the aetiology of type 2 diabetes (T2D) is still incompletely understood. It is well established that increased endogenous glucose production (EGP) leads to a progressive increase in glucose levels, causing insulin resistance and eventual loss of glucose homeostasis. The consumption of high carbohydrate, high-fat, western style diet (HFD) is linked to the development of T2D and obesity, whereas the consumption of a low carbohydrate, high-fat, ketogenic diet (KD) is considered healthy. However, several days of carbohydrate restriction are known to cause selective hepatic insulin resistance. In the present study, we compare the effects of short-term HFD and KD feeding on glucose homeostasis in mice. We show that, even though KD fed animals appear to be healthy in the fasted state, they exhibit decreased glucose tolerance to a greater extent than HFD fed animals. Furthermore, we show that this effect originates from blunted suppression of hepatic glucose production by insulin, rather than impaired glucose clearance and tissue glucose uptake. These data suggest that the early effects of HFD consumption on EGP may be part of a normal physiological response to increased lipid intake and oxidation, and that systemic insulin resistance results from the addition of dietary glucose to EGP-derived glucose.
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86
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Senn JR, Maushart CI, Gashi G, Michel R, Lalive d'Epinay M, Vogt R, Becker AS, Müller J, Baláz M, Wolfrum C, Burger IA, Betz MJ. Outdoor Temperature Influences Cold Induced Thermogenesis in Humans. Front Physiol 2018; 9:1184. [PMID: 30190681 PMCID: PMC6115528 DOI: 10.3389/fphys.2018.01184] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Accepted: 08/06/2018] [Indexed: 11/16/2022] Open
Abstract
Objective: Energy expenditure (EE) increases in response to cold exposure, which is called cold induced thermogenesis (CIT). Brown adipose tissue (BAT) has been shown to contribute significantly to CIT in human adults. BAT activity and CIT are acutely influenced by ambient temperature. In the present study, we investigated the long-term effect of seasonal temperature variation on human CIT. Materials and Methods: We measured CIT in 56 healthy volunteers by indirect calorimetry. CIT was determined as difference between EE during warm conditions (EEwarm) and after a defined cold stimulus (EEcold). We recorded skin temperatures at eleven anatomically predefined locations, including the supraclavicular region, which is adjacent to the main human BAT depot. We analyzed the relation of EE, CIT and skin temperatures to the daily minimum, maximum and mean outdoor temperature averaged over 7 or 30 days, respectively, prior to the corresponding study visit by linear regression. Results: We observed a significant inverse correlation between outdoor temperatures and EEcold and CIT, respectively, while EEwarm was not influenced. The daily maximum temperature averaged over 7 days correlated best with EEcold (R2 = 0.123, p = 0.008) and CIT (R2 = 0.200, p = 0.0005). The mean skin temperatures before and after cold exposure were not related to outdoor temperatures. However, the difference between supraclavicular and parasternal skin temperature after cold exposure was inversely related to the average maximum temperature during the preceding 7 days (R2 = 0.07575, p = 0.0221). Conclusion: CIT is significantly related to outdoor temperatures indicating dynamic adaption of thermogenesis and BAT activity to environmental stimuli in adult humans. Clinical Trial Registration:www.ClinicalTrials.gov, Identifier NCT02682706.
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87
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Balazova L, Wolfrum C, Balaz M. Weight Loss and Adipose Tissue Browning in Humans: The Chicken or the Egg? Trends Endocrinol Metab 2018; 29:450-452. [PMID: 29548805 DOI: 10.1016/j.tem.2018.03.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Accepted: 03/02/2018] [Indexed: 01/05/2023]
Abstract
Recruitment of thermogenic adipocytes within white fat depots represents a promising strategy to increase energy expenditure. Negative energy balance has been reported to promote adipose tissue browning in rodents. In a recent issue of Cell Reports, Barquissau et al. show that caloric restriction-associated weight loss does not induce browning of subcutaneous abdominal white fat in obese humans.
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Schwalie PC, Dong H, Zachara M, Russeil J, Alpern D, Akchiche N, Caprara C, Sun W, Schlaudraff KU, Soldati G, Wolfrum C, Deplancke B. A stromal cell population that inhibits adipogenesis in mammalian fat depots. Nature 2018; 559:103-108. [PMID: 29925944 DOI: 10.1038/s41586-018-0226-8] [Citation(s) in RCA: 284] [Impact Index Per Article: 47.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Accepted: 05/16/2018] [Indexed: 02/07/2023]
Abstract
Adipocyte development and differentiation have an important role in the aetiology of obesity and its co-morbidities1,2. Although multiple studies have investigated the adipogenic stem and precursor cells that give rise to mature adipocytes3-14, our understanding of their in vivo origin and properties is incomplete2,15,16. This is partially due to the highly heterogeneous and unstructured nature of adipose tissue depots17, which has proven difficult to molecularly dissect using classical approaches such as fluorescence-activated cell sorting and Cre-lox lines based on candidate marker genes16,18. Here, using the resolving power of single-cell transcriptomics19 in a mouse model, we reveal distinct subpopulations of adipose stem and precursor cells in the stromal vascular fraction of subcutaneous adipose tissue. We identify one of these subpopulations as CD142+ adipogenesis-regulatory cells, which can suppress adipocyte formation in vivo and in vitro in a paracrine manner. We show that adipogenesis-regulatory cells are refractory to adipogenesis and that they are functionally conserved in humans. Our findings point to a potentially critical role for adipogenesis-regulatory cells in modulating adipose tissue plasticity, which is linked to metabolic control, differential insulin sensitivity and type 2 diabetes.
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Langhans W, Adan R, Arnold M, Banks WA, Card JP, Dailey MJ, Daniels D, de Kloet AD, de Lartigue G, Dickson S, Fedele S, Grill HJ, Jansson JO, Kaufman S, Kolar G, Krause E, Lee SJ, Le Foll C, Levin BE, Lutz TA, Mansouri A, Moran TH, Pacheco-López G, Ramachandran D, Raybould H, Rinaman L, Samson WK, Sanchez-Watts G, Seeley RJ, Skibicka KP, Small D, Spector AC, Tamashiro KL, Templeton B, Trapp S, Tso P, Watts AG, Weissfeld N, Williams D, Wolfrum C, Yosten G, Woods SC. New horizons for future research - Critical issues to consider for maximizing research excellence and impact. Mol Metab 2018; 14:53-59. [PMID: 29886182 PMCID: PMC6034110 DOI: 10.1016/j.molmet.2018.05.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Revised: 05/08/2018] [Accepted: 05/08/2018] [Indexed: 12/18/2022] Open
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Stadion M, Schwerbel K, Graja A, Baumeier C, Rödiger M, Jonas W, Wolfrum C, Staiger H, Fritsche A, Häring HU, Klöting N, Blüher M, Fischer-Posovszky P, Schulz TJ, Joost HG, Vogel H, Schürmann A. Increased Ifi202b/IFI16 expression stimulates adipogenesis in mice and humans. Diabetologia 2018; 61:1167-1179. [PMID: 29478099 PMCID: PMC6448999 DOI: 10.1007/s00125-018-4571-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/24/2017] [Accepted: 01/19/2018] [Indexed: 02/07/2023]
Abstract
AIMS/HYPOTHESIS Obesity results from a constant and complex interplay between environmental stimuli and predisposing genes. Recently, we identified the IFN-activated gene Ifi202b as the most likely gene responsible for the obesity quantitative trait locus Nob3 (New Zealand Obese [NZO] obesity 3). The aim of this study was to evaluate the effects of Ifi202b on body weight and adipose tissue biology, and to clarify the functional role of its human orthologue IFI16. METHODS The impact of Ifi202b and its human orthologue IFI16 on adipogenesis was investigated by modulating their respective expression in murine 3T3-L1 and human Simpson-Golabi-Behmel syndrome (SGBS) pre-adipocytes. Furthermore, transgenic mice overexpressing IFI202b were generated and characterised with respect to metabolic traits. In humans, expression levels of IFI16 in adipose tissue were correlated with several variables of adipocyte function. RESULTS In mice, IFI202b overexpression caused obesity (Δ body weight at the age of 30 weeks: 10.2 ± 1.9 g vs wild-type mice) marked by hypertrophic fat mass expansion, increased expression of Zfp423 (encoding the transcription factor zinc finger protein [ZFP] 423) and white-selective genes (Tcf21, Tle3), and decreased expression of thermogenic genes (e.g. Cidea, Ucp1). Compared with their wild-type littermates, Ifi202b transgenic mice displayed lower body temperature, hepatosteatosis and systemic insulin resistance. Suppression of IFI202b/IFI16 in pre-adipocytes impaired adipocyte differentiation and triacylglycerol storage. Humans with high levels of IFI16 exhibited larger adipocytes, an enhanced inflammatory state and impaired insulin-stimulated glucose uptake in white adipose tissue. CONCLUSIONS/INTERPRETATION Our findings reveal novel functions of Ifi202b and IFI16, demonstrating their role as obesity genes. These genes promote white adipogenesis and fat storage, thereby facilitating the development of obesity-associated insulin resistance.
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Jomard A, Doytcheva P, Deuel J, Luscher T, Wolfrum C, Lutz T, Osto E. P533The functional relevance of HDL structure and composition in the improvement of cholesterol efflux capacity after Roux-en-Y gastric bypass. Cardiovasc Res 2018. [DOI: 10.1093/cvr/cvy060.389] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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92
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Wolfrum C, Peleg-Raibstein D. Maternal overnutrition leads to cognitive and neurochemical abnormalities in C57BL/6 mice. Nutr Neurosci 2018; 22:688-699. [DOI: 10.1080/1028415x.2018.1432096] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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93
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Grandl G, Wolfrum C. Hemostasis, endothelial stress, inflammation, and the metabolic syndrome. Semin Immunopathol 2018; 40:215-224. [PMID: 29209827 PMCID: PMC5809518 DOI: 10.1007/s00281-017-0666-5] [Citation(s) in RCA: 164] [Impact Index Per Article: 27.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2017] [Accepted: 11/14/2017] [Indexed: 12/23/2022]
Abstract
Obesity and the metabolic syndrome (MS) are two of the pressing healthcare problems of our time. The MS is defined as increased abdominal obesity in concert with elevated fasting glucose levels, insulin resistance, elevated blood pressure, and plasma lipids. It is a key risk factor for type 2 diabetes mellitus (T2DM) and for cardiovascular complications and mortality. Here, we review work demonstrating that various aspects of coagulation and hemostasis, as well as vascular reactivity and function, become impaired progressively during chronic ingestion of a western diet, but also acutely after meals. We outline that both T2DM and cardiovascular disease should be viewed as inflammatory diseases and describe that chronic overload of free fatty acids and glucose can trigger inflammatory pathways directly or via increased production of ROS. We propose that since endothelial stress and increases in platelet activity precede inflammation and overt symptoms of the MS, they are likely the first hit. This suggests that endothelial activation and insulin resistance are probably causative in the observed chronic low-level metabolic inflammation, and thus both metabolic and cardiovascular complications linked to consumption of a western diet.
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Sanchez-Gurmaches J, Tang Y, Jespersen NZ, Wallace M, Martinez Calejman C, Gujja S, Li H, Edwards YJK, Wolfrum C, Metallo CM, Nielsen S, Scheele C, Guertin DA. Brown Fat AKT2 Is a Cold-Induced Kinase that Stimulates ChREBP-Mediated De Novo Lipogenesis to Optimize Fuel Storage and Thermogenesis. Cell Metab 2018; 27:195-209.e6. [PMID: 29153407 PMCID: PMC5762420 DOI: 10.1016/j.cmet.2017.10.008] [Citation(s) in RCA: 135] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Revised: 06/30/2017] [Accepted: 10/18/2017] [Indexed: 12/13/2022]
Abstract
Brown adipose tissue (BAT) is a therapeutic target for metabolic diseases; thus, understanding its metabolic circuitry is clinically important. Many studies of BAT compare rodents mildly cold to those severely cold. Here, we compared BAT remodeling between thermoneutral and mild-cold-adapted mice, conditions more relevant to humans. Although BAT is renowned for catabolic β-oxidative capacity, we find paradoxically that the anabolic de novo lipogenesis (DNL) genes encoding ACLY, ACSS2, ACC, and FASN were among the most upregulated by mild cold and that, in humans, DNL correlates with Ucp1 expression. The regulation and function of adipocyte DNL and its association with thermogenesis are not understood. We provide evidence suggesting that AKT2 drives DNL in adipocytes by stimulating ChREBPβ transcriptional activity and that cold induces the AKT2-ChREBP pathway in BAT to optimize fuel storage and thermogenesis. These data provide insight into adipocyte DNL regulation and function and illustrate the metabolic flexibility of thermogenesis.
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Abstract
The adult human adipose tissue is predominantly composed of white adipocytes. However, within certain depots, adipose tissue contains thermogenically active brown-like adipocytes, which have been evolutionarily conserved in mammals. This chapter will give a brief overview on the methods used to genetically target and trace both white and brown adipocytes using techniques such as bacterial artificial chromosome (BAC) cloning to create transgenic mouse models and the tools with which genetic recombination is mediated in vivo (e.g., Cre-loxP, CreERT, and Tet-On). The chapter furthermore critically discusses the strength and limitation of the various systems used to target mature white and brown adipocytes (ap2-Cre, Adipoq-Cre, and Ucp1-Cre). Based on these systems, it is evident that our knowledge of mature adipocyte categorization into brown, white, brite, or beige adipocytes is strongly influenced by the use of the various genetic mouse models described in this chapter. Our evaluation of different studies using the aforementioned systems focuses on key genes, which have been reported to maintain adipocyte's function (insulin receptor, Raptor, or Atgl).
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96
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Schosserer M, Grillari J, Wolfrum C, Scheideler M. Age-Induced Changes in White, Brite, and Brown Adipose Depots: A Mini-Review. Gerontology 2017; 64:229-236. [DOI: 10.1159/000485183] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2017] [Accepted: 11/13/2017] [Indexed: 11/19/2022] Open
Abstract
Aging is a time-related process of functional decline at organelle, cellular, tissue, and organismal level that ultimately limits life. Cellular senescence is a state of permanent growth arrest in response to stress and one of the major drivers of aging and age-related disorders. Senescent cells accumulate with age, and removal of these cells delays age-related disorders in different tissues and prolongs healthy lifespan. One of the most studied aging mechanisms is the accumulation of reactive oxygen species damage in cells, organs, and organisms over time. Elevated oxidative stress is also found in metabolic diseases such as obesity, metabolic syndrome and associated disorders. Moreover, dysregulation of the energy homeostasis is also associated with aging, and many age-related genes also control energy metabolism, with the adipose organ, comprising white, brite, and brown adipocytes, as an important metabolic player in the regulation of whole-body energy homeostasis. This review summarizes transformations in the adipose organ upon aging and cellular senescence and sheds light on the reallocation of fat mass between adipose depots, on the metabolism of white and brown adipose tissue, on the regenerative potential and adipogenic differentiation capacity of preadipocytes, and on alterations in mitochondria and bioenergetics. In conclusion, the aging process is a lifelong, creeping process with gradual decline in (pre-)adipocyte function over time. Thus, slowing down the accumulation of (pre-)adipocyte damage and dysfunction, removal of senescent preadipocytes as well as blocking deleterious compounds of the senescent secretome are protective measures to maintain a lasting state of health at old age.
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Dalmas E, Lehmann FM, Dror E, Wueest S, Thienel C, Borsigova M, Stawiski M, Traunecker E, Lucchini FC, Dapito DH, Kallert SM, Guigas B, Pattou F, Kerr-Conte J, Maechler P, Girard JP, Konrad D, Wolfrum C, Böni-Schnetzler M, Finke D, Donath MY. Interleukin-33-Activated Islet-Resident Innate Lymphoid Cells Promote Insulin Secretion through Myeloid Cell Retinoic Acid Production. Immunity 2017; 47:928-942.e7. [PMID: 29166590 DOI: 10.1016/j.immuni.2017.10.015] [Citation(s) in RCA: 112] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2016] [Revised: 07/24/2017] [Accepted: 10/26/2017] [Indexed: 01/04/2023]
Abstract
Pancreatic-islet inflammation contributes to the failure of β cell insulin secretion during obesity and type 2 diabetes. However, little is known about the nature and function of resident immune cells in this context or in homeostasis. Here we show that interleukin (IL)-33 was produced by islet mesenchymal cells and enhanced by a diabetes milieu (glucose, IL-1β, and palmitate). IL-33 promoted β cell function through islet-resident group 2 innate lymphoid cells (ILC2s) that elicited retinoic acid (RA)-producing capacities in macrophages and dendritic cells via the secretion of IL-13 and colony-stimulating factor 2. In turn, local RA signaled to the β cells to increase insulin secretion. This IL-33-ILC2 axis was activated after acute β cell stress but was defective during chronic obesity. Accordingly, IL-33 injections rescued islet function in obese mice. Our findings provide evidence that an immunometabolic crosstalk between islet-derived IL-33, ILC2s, and myeloid cells fosters insulin secretion.
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98
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Nicolaou A, Northoff BH, Sass K, Ernst J, Kohlmaier A, Krohn K, Wolfrum C, Teupser D, Holdt LM. Quantitative trait locus mapping in mice identifies phospholipase Pla2g12a as novel atherosclerosis modifier. Atherosclerosis 2017; 265:197-206. [PMID: 28917158 DOI: 10.1016/j.atherosclerosis.2017.08.030] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Revised: 08/23/2017] [Accepted: 08/24/2017] [Indexed: 01/06/2023]
Abstract
BACKGROUND AND AIMS In a previous work, a female-specific atherosclerosis risk locus on chromosome (Chr) 3 was identified in an intercross of atherosclerosis-resistant FVB and atherosclerosis-susceptible C57BL/6 (B6) mice on the LDL-receptor deficient (Ldlr-/-) background. It was the aim of the current study to identify causative genes at this locus. METHODS We established a congenic mouse model, where FVB.Chr3B6/B6 mice carried an 80 Mb interval of distal Chr3 on an otherwise FVB.Ldlr-/- background, to validate the Chr3 locus. Candidate genes were identified using genome-wide expression analyses. Differentially expressed genes were validated using quantitative PCRs in F0 and F2 mice and their functions were investigated in pathophysiologically relevant cells. RESULTS Fine-mapping of the Chr3 locus revealed two overlapping, yet independent subloci for female atherosclerosis susceptibility: when transmitted by grandfathers to granddaughters, the B6 risk allele increased atherosclerosis and downregulated the expression of the secreted phospholipase Pla2g12a (2.6 and 2.2 fold, respectively); when inherited by grandmothers, the B6 risk allele induced vascular cell adhesion molecule 1 (Vcam1). Down-regulation of Pla2g12a and up-regulation of Vcam1 were validated in female FVB.Chr3B6/B6 congenic mice, which developed 2.5 greater atherosclerotic lesions compared to littermate controls (p=0.039). Pla2g12a was highly expressed in aortic endothelial cells in vivo, and knocking-down Pla2g12a expression by RNAi in cultured vascular endothelial cells or macrophages increased their adhesion to ECs in vitro. CONCLUSIONS Our data establish Pla2g12a as an atheroprotective candidate gene in mice, where high expression levels in ECs and macrophages may limit the recruitment and accumulation of these cells in nascent atherosclerotic lesions.
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Kälin S, Becker M, Ott VB, Serr I, Hosp F, Mollah MMH, Keipert S, Lamp D, Rohner-Jeanrenaud F, Flynn VK, Scherm MG, Nascimento LFR, Gerlach K, Popp V, Dietzen S, Bopp T, Krishnamurthy P, Kaplan MH, Serrano M, Woods SC, Tripal P, Palmisano R, Jastroch M, Blüher M, Wolfrum C, Weigmann B, Ziegler AG, Mann M, Tschöp MH, Daniel C. A Stat6/Pten Axis Links Regulatory T Cells with Adipose Tissue Function. Cell Metab 2017; 26:475-492.e7. [PMID: 28877454 PMCID: PMC5627977 DOI: 10.1016/j.cmet.2017.08.008] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/29/2016] [Revised: 07/21/2017] [Accepted: 08/08/2017] [Indexed: 12/22/2022]
Abstract
Obesity and type 2 diabetes are associated with metabolic defects and adipose tissue inflammation. Foxp3+ regulatory T cells (Tregs) control tissue homeostasis by counteracting local inflammation. However, if and how T cells interlink environmental influences with adipocyte function remains unknown. Here, we report that enhancing sympathetic tone by cold exposure, beta3-adrenergic receptor (ADRB3) stimulation or a short-term high-calorie diet enhances Treg induction in vitro and in vivo. CD4+ T cell proteomes revealed higher expression of Foxp3 regulatory networks in response to cold or ADRB3 stimulation in vivo reflecting Treg induction. Specifically, Ragulator-interacting protein C17orf59, which limits mTORC1 activity, was upregulated in CD4+ T cells by either ADRB3 stimulation or cold exposure, suggesting contribution to Treg induction. By loss- and gain-of-function studies, including Treg depletion and transfers in vivo, we demonstrated that a T cell-specific Stat6/Pten axis links cold exposure or ADRB3 stimulation with Foxp3+ Treg induction and adipose tissue function. Our findings offer a new mechanistic model in which tissue-specific Tregs maintain adipose tissue function.
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Marzolla V, Taheri A, Caprio M, Wolfrum C, Lutz T, Luscher T, Osto E. P3477Role of glucagon-like peptides and glucagon in the control of vascular function. Eur Heart J 2017. [DOI: 10.1093/eurheartj/ehx504.p3477] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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