| 1. |
- Fischer, Katrin, et al.
(författare)
-
Alternatively activated macrophages do not synthesize catecholamines or contribute to adipose tissue adaptive thermogenesis
- 2017
-
Ingår i: Nature Medicine. - : Springer Science and Business Media LLC. - 1078-8956 .- 1546-170X. ; 23:5, s. 623-630
-
Tidskriftsartikel (refereegranskat)abstract
- Adaptive thermogenesis is the process of heat generation in response to cold stimulation. It is under the control of the sympathetic nervous system, whose chief effector is the catecholamine norepinephrine (NE). NE enhances thermogenesis through beta 3-adrenergic receptors to activate brown adipose tissue and by 'browning' white adipose tissue. Recent studies have reported that alternative activation of macrophages in response to interleukin (IL)-4 stimulation induces the expression of tyrosine hydroxylase (TH), a key enzyme in the catecholamine synthesis pathway, and that this activation provides an alternative source of locally produced catecholamines during the thermogenic process. Here we report that the deletion of Th in hematopoietic cells of adult mice neither alters energy expenditure upon cold exposure nor reduces browning in inguinal adipose tissue. Bone marrow-derived macrophages did not release NE in response to stimulation with IL-4, and conditioned media from IL-4-stimulated macrophages failed to induce expression of thermogenic genes, such as uncoupling protein 1 (Ucp1), in adipocytes cultured with the conditioned media. Furthermore, chronic treatment with IL-4 failed to increase energy expenditure in wild-type, Ucp1(-/-) and interleukin-4 receptor-alpha double-negative (Il4ra(-/-)) mice. In agreement with these findings, adipose-tissue-resident macrophages did not express TH. Thus, we conclude that alternatively activated macrophages do not synthesize relevant amounts of catecholamines, and hence, are not likely to have a direct role in adipocyte metabolism or adaptive thermogenesis.
|
|
| 2. |
- Fischer, Katrin, et al.
(författare)
-
The scaffold protein p62 regulates adaptive thermogenesis through ATF2 nuclear target activation
- 2020
-
Ingår i: Nature Communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 11:1
-
Tidskriftsartikel (refereegranskat)abstract
- During beta -adrenergic stimulation of brown adipose tissue (BAT), p38 phosphorylates the activating transcription factor 2 (ATF2) which then translocates to the nucleus to activate the expression of Ucp1 and Pgc-1 alpha. The mechanisms underlying ATF2 target activation are unknown. Here we demonstrate that p62 (Sqstm1) binds to ATF2 to orchestrate activation of the Ucp1 enhancer and Pgc-1 alpha promoter. P62(Delta 69-251) mice show reduced expression of Ucp1 and Pgc-1 alpha with impaired ATF2 genomic binding. Modulation of Ucp1 and Pgc-1 alpha expression through p62 regulation of ATF2 signaling is demonstrated in vitro and in vivo in p62(Delta 69-251) mice, global p62(-/-) and Ucp1-Cre p62(flx/flx) mice. BAT dysfunction resulting from p62 deficiency is manifest after birth and obesity subsequently develops despite normal food intake, intestinal nutrient absorption and locomotor activity. In summary, our data identify p62 as a master regulator of BAT function in that it controls the Ucp1 pathway through regulation of ATF2 genomic binding. Beta-adrenergic stimulation of brown adipose tissue leads to thermogenesis via the activating transcription factor 2 (ATF2) mediated expression of the thermogenic genes Ucp1 and Pgc-1 alpha. Here, the authors show that the scaffold protein p62 regulates brown adipose tissue function through modifying ATF2 genomic binding and subsequent Ucp1 and Pgc-1 alpha induction.
|
|
| 3. |
- Gonzalez-Franquesa, Alba, et al.
(författare)
-
Discovery of thymosin β4 as a human exerkine and growth factor
- 2021
-
Ingår i: American Journal of Physiology - Cell Physiology. - : American Physiological Society. - 0363-6143 .- 1522-1563. ; 321:5, s. 770-778
-
Tidskriftsartikel (refereegranskat)abstract
- Skeletal muscle is an endocrine organ secreting exercise-induced factors (exerkines), which play a pivotal role in interorgan cross talk. Using mass spectrometry (MS)-based proteomics, we characterized the secretome and identified thymosin b4 (TMSB4X) as the most upregulated secreted protein in the media of contracting C2C12 myotubes. TMSB4X was also acutely increased in the plasma of exercising humans irrespective of the insulin resistance condition or exercise mode. Treatment of mice with TMSB4X did not ameliorate the metabolic disruptions associated with diet induced-obesity, nor did it enhance muscle regeneration in vivo. However, TMSB4X increased osteoblast proliferation and neurite outgrowth, consistent with its WADA classification as a prohibited growth factor. Therefore, we report TMSB4X as a human exerkine with a potential role in cellular cross talk.
|
|
| 4. |
- Kyhl, Kasper, et al.
(författare)
-
Complete Revascularization Versus Culprit Lesion Only in Patients With ST-Segment Elevation Myocardial Infarction and Multivessel Disease : A DANAMI-3–PRIMULTI Cardiac Magnetic Resonance Substudy
- 2019
-
Ingår i: JACC: Cardiovascular Interventions. - : Elsevier BV. - 1936-8798. ; 12:8, s. 721-730
-
Tidskriftsartikel (refereegranskat)abstract
- Objectives: The aim of this study was to evaluate the effect of fractional flow reserve (FFR)–guided revascularization compared with culprit-only percutaneous coronary intervention (PCI) in patients with ST-segment elevation myocardial infarction (STEMI) on infarct size, left ventricular (LV), function, LV remodeling, and the presence of nonculprit infarctions. Background: Patients with STEMI with multivessel disease might have improved clinical outcomes after complete revascularization compared with PCI of the infarct-related artery only, but the impact on infarct size, LV function, and remodeling as well as the risk for periprocedural infarction are unknown. Methods: In this substudy of the DANAMI-3 (Third Danish Trial in Acute Myocardial Infarction)–PRIMULTI (Primary PCI in Patients With ST-Elevation Myocardial Infarction and Multivessel Disease: Treatment of Culprit Lesion Only or Complete Revascularization) randomized trial, patients with STEMI with multivessel disease were randomized to receive either complete FFR-guided revascularization or PCI of the culprit vessel only. The patients underwent cardiac magnetic resonance imaging during index admission and at 3-month follow-up. Results: A total of 280 patients (136 patients with infarct-related and 144 with complete FFR-guided revascularization) were included. There were no differences in final infarct size (median 12% [interquartile range: 5% to 19%] vs. 11% [interquartile range: 4% to 18%]; p = 0.62), myocardial salvage index (median 0.71 [interquartile range: 0.54 to 0.89] vs. 0.66 [interquartile range: 0.55 to 0.87]; p = 0.49), LV ejection fraction (mean 58 ± 9% vs. 59 ± 9%; p = 0.39), and LV end-systolic volume remodeling (mean 7 ± 22 ml vs. 7 ± 19 ml; p = 0.63). New nonculprit infarction occurring after the nonculprit intervention was numerically more frequent among patients treated with complete revascularization (6 [4.5%] vs. 1 [0.8%]; p = 0.12). Conclusions: Complete FFR-guided revascularization in patients with STEMI and multivessel disease did not affect final infarct size, LV function, or remodeling compared with culprit-only PCI.
|
|
| 5. |
- Tobias, Deirdre K, et al.
(författare)
-
Second international consensus report on gaps and opportunities for the clinical translation of precision diabetes medicine
- 2023
-
Ingår i: Nature Medicine. - 1546-170X. ; 29:10, s. 2438-2457
-
Forskningsöversikt (refereegranskat)abstract
- Precision medicine is part of the logical evolution of contemporary evidence-based medicine that seeks to reduce errors and optimize outcomes when making medical decisions and health recommendations. Diabetes affects hundreds of millions of people worldwide, many of whom will develop life-threatening complications and die prematurely. Precision medicine can potentially address this enormous problem by accounting for heterogeneity in the etiology, clinical presentation and pathogenesis of common forms of diabetes and risks of complications. This second international consensus report on precision diabetes medicine summarizes the findings from a systematic evidence review across the key pillars of precision medicine (prevention, diagnosis, treatment, prognosis) in four recognized forms of diabetes (monogenic, gestational, type 1, type 2). These reviews address key questions about the translation of precision medicine research into practice. Although not complete, owing to the vast literature on this topic, they revealed opportunities for the immediate or near-term clinical implementation of precision diabetes medicine; furthermore, we expose important gaps in knowledge, focusing on the need to obtain new clinically relevant evidence. Gaps include the need for common standards for clinical readiness, including consideration of cost-effectiveness, health equity, predictive accuracy, liability and accessibility. Key milestones are outlined for the broad clinical implementation of precision diabetes medicine.
|
|
