| 1. |
- Rydén, Mikael, et al.
(författare)
-
Lipolysis defect in people with obesity who undergo metabolic surgery
- 2022
-
Ingår i: Journal of Internal Medicine. - : Wiley-Blackwell Publishing Inc.. - 0954-6820 .- 1365-2796. ; 292:4, s. 667-678
-
Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: Cross-sectional studies demonstrate that catecholamine stimulation of fat cell lipolysis is blunted in obesity. We investigated whether this defect persists after substantial weight loss has been induced by metabolic surgery, and whether it is related to the outcome.DESIGN/METHODS: Patients with obesity not able to successfully reduce body weight by conventional means (n = 126) were investigated before and 5 years after Roux-en-Y gastric bypass surgery (RYGB). They were compared with propensity-score matched subjects selected from a control group (n = 1017), and with the entire group after adjustment for age, sex, body mass index (BMI), fat cell volume and other clinical parameters. Catecholamine-stimulated lipolysis (glycerol release) was investigated in isolated fat cells using noradrenaline (natural hormone) or isoprenaline (synthetic beta-adrenoceptor agonist).RESULTS: Following RYGB, BMI was reduced from 39.9 (37.5-43.5) (median and interquartile range) to 29.5 (26.7-31.9) kg/m2 (p < 0.0001). The post-RYGB patients had about 50% lower lipolysis rates compared with the matched and total series of controls (p < 0.0005). Nordrenaline activation of lipolysis at baseline was associated with the RYGB effect; those with high lipolysis activation (upper tertile) lost 30%-45% more in body weight, BMI or fat mass than those with low (bottom tertile) initial lipolysis activation (p < 0.0007).CONCLUSION: Patients with obesity requiring metabolic surgery have impaired ability of catecholamines to stimulate lipolysis, which remains despite long-term normalization of body weight by RYGB. Furthermore, preoperative variations in the ability of catecholamines to activate lipolysis may predict the long-term reduction in body weight and fat mass.
|
|
| 2. |
- Li, Mei, et al.
(författare)
-
Development and prevention of ischemic contracture (“stone heart”) in the pig heart
- 2023
-
Ingår i: Frontiers in Cardiovascular Medicine. - : Frontiers Media SA. - 2297-055X. ; 10
-
Tidskriftsartikel (refereegranskat)abstract
- Stone heart (ischemic contracture) is a rare and serious condition observed in the heart after periods of warm ischemia. The underlying mechanisms are largely unknown and treatment options are lacking. In view of the possibilities for cardiac donation after circulatory death (DCD), introducing risks for ischemic damage, we have investigated stone heart in pigs. Following cessation of ventilation, circulatory death (systolic pressure <8 mmHg) occurred within 13.1 ± 1.2 min; and a stone heart, manifested with asystole, increased left ventricular wall thickness and stiffness, established after a further 17 ± 6 min. Adenosine triphosphate and phosphocreatine levels decreased by about 50% in the stone heart. Electron microscopy showed deteriorated structure with contraction bands, Z-line streaming and swollen mitochondria. Synchrotron based small angle X-ray scattering of trabecular samples from stone hearts revealed attachment of myosin to actin, without volume changes in the sarcomeres. Ca2+ sensitivity, determined in permeabilized muscle, was increased in stone heart samples. An in vitro model for stone heart, using isolated trabecular muscle exposed to hypoxia/zero glucose, exhibited the main characteristics of stone heart in whole animals, with a fall in high-energy phosphates and development of muscle contracture. The stone heart condition in vitro was significantly attenuated by the myosin inhibitor MYK-461 (Mavacamten). In conclusion, the stone heart is a hypercontracted state associated with myosin binding to actin and increased Ca2+ sensitivity. The hypercontractile state, once developed, is poorly reversible. The myosin inhibitor MYK-461, which is clinically approved for other indications, could be a promising venue for prevention.
|
|
| 3. |
- Pillon, Nicolas J., et al.
(författare)
-
Distinctive exercise-induced inflammatory response and exerkine induction in skeletal muscle of people with type 2 diabetes
- 2022
-
Ingår i: Science Advances. - : NLM (Medline). - 2375-2548. ; 8:36
-
Tidskriftsartikel (refereegranskat)abstract
- Mechanistic insights into the molecular events by which exercise enhances the skeletal muscle phenotype are lacking, particularly in the context of type 2 diabetes. Here, we unravel a fundamental role for exercise-responsive cytokines (exerkines) on skeletal muscle development and growth in individuals with normal glucose tolerance or type 2 diabetes. Acute exercise triggered an inflammatory response in skeletal muscle, concomitant with an infiltration of immune cells. These exercise effects were potentiated in type 2 diabetes. In response to contraction or hypoxia, cytokines were mainly produced by endothelial cells and macrophages. The chemokine CXCL12 was induced by hypoxia in endothelial cells, as well as by conditioned medium from contracted myotubes in macrophages. We found that CXCL12 was associated with skeletal muscle remodeling after exercise and differentiation of cultured muscle. Collectively, acute aerobic exercise mounts a noncanonical inflammatory response, with an atypical production of exerkines, which is potentiated in type 2 diabetes.
|
|
| 4. |
- Reitzner, Stefan M., et al.
(författare)
-
Molecular profiling of high-level athlete skeletal muscle after acute endurance or resistance exercise : A systems biology approach
- 2024
-
Ingår i: Molecular Metabolism. - : Elsevier GmbH. - 2212-8778. ; 79
-
Tidskriftsartikel (refereegranskat)abstract
- Objective: Long-term high-level exercise training leads to improvements in physical performance and multi-tissue adaptation following changes in molecular pathways. While skeletal muscle baseline differences between exercise-trained and untrained individuals have been previously investigated, it remains unclear how training history influences human multi-omics responses to acute exercise. Methods: We recruited and extensively characterized 24 individuals categorized as endurance athletes with >15 years of training history, strength athletes or control subjects. Timeseries skeletal muscle biopsies were taken from M. vastus lateralis at three time-points after endurance or resistance exercise was performed and multi-omics molecular analysis performed. Results: Our analyses revealed distinct activation differences of molecular processes such as fatty- and amino acid metabolism and transcription factors such as HIF1A and the MYF-family. We show that endurance athletes have an increased abundance of carnitine-derivates while strength athletes increase specific phospholipid metabolites compared to control subjects. Additionally, for the first time, we show the metabolite sorbitol to be substantially increased with acute exercise. On transcriptional level, we show that acute resistance exercise stimulates more gene expression than acute endurance exercise. This follows a specific pattern, with endurance athletes uniquely down-regulating pathways related to mitochondria, translation and ribosomes. Finally, both forms of exercise training specialize in diverging transcriptional directions, differentiating themselves from the transcriptome of the untrained control group. Conclusions: We identify a “transcriptional specialization effect” by transcriptional narrowing and intensification, and molecular specialization effects on metabolomic level Additionally, we performed multi-omics network and cluster analysis, providing a novel resource of skeletal muscle transcriptomic and metabolomic profiling in highly trained and untrained individuals.
|
|
| 5. |
- Szekeres, Ferenc L. M., et al.
(författare)
-
A small molecule inhibitor of Nox2 and Nox4 improves contractile function after ischemia–reperfusion in the mouse heart
- 2021
-
Ingår i: Scientific Reports. - : Springer Nature. - 2045-2322. ; 11:1
-
Tidskriftsartikel (refereegranskat)abstract
- The NADPH oxidase enzymes Nox2 and 4, are important generators of Reactive oxygen species (ROS). These enzymes are abundantly expressed in cardiomyocytes and have been implicated in ischemia–reperfusion injury. Previous attempts with full inhibition of their activity using genetically modified animals have shown variable results, suggesting that a selective and graded inhibition could be a more relevant approach. We have, using chemical library screening, identified a new compound (GLX481304) which inhibits Nox 2 and 4 (with IC50 values of 1.25 µM) without general antioxidant effects or inhibitory effects on Nox 1. The compound inhibits ROS production in isolated mouse cardiomyocytes and improves cardiomyocyte contractility and contraction of whole retrogradely (Langendorff) perfused hearts after a global ischemia period. We conclude that a pharmacological and partial inhibition of ROS production by inhibition of Nox 2 and 4 is beneficial for recovery after ischemia reperfusion and might be a promising venue for treatment of ischemic injury to the heart.
|
|
| 6. |
- Tabrizi, Fara, et al.
(författare)
-
P117. Predicting Genetic Risk for Depression and Anxiety Disorders
- 2022
-
Ingår i: Biological Psychiatry. - : Elsevier BV. - 0006-3223 .- 1873-2402. ; 91
-
Tidskriftsartikel (refereegranskat)abstract
- BackgroundPolygenic scores (PGSs) harness the potential to provide an overall measure of individuals’ genetic liability to develop a disease (Torkamani et al., 2018), though much research is still needed. The aim of the present study was to predict prescription of pharmacological treatment of anxiety or depression from PGSs.MethodsThe target sample comprised two cohorts of genotyped Swedish twins (n = 11037). Cases were defined as individuals prescribed pharmacological treatment of depression (n = 1129) or anxiety (n = 1446). We constructed 6 PGSs based on GWAS on MDD diagnosis, Anxiety, Schizophrenia, Neuroticism scores, the GAD-7 scale, and the PHQ-9. Data were analyzed by logistic regression models with change in pseudo-R2 (above the baseline model with sex, age, cohort, and 20 ancestral PCs) following the inclusion of PGSs to predict the risk of anxiety or depression medication. All results corrected for multiple comparisons.ResultsPredictive performance was estimated to ΔR2depression = 0.028; ΔR2anxiety = 0.025 when all PGSs were included in the same model, with PGS for MDD being the single best predictor for both anxiety and depression. Individuals in the top 10% of the PGS distribution had greater odds of drug prescription (ORdepression = 1.82; CI95% = 1.53—2.17; ORanxiety = 1.65; CI95% = 1.40—1.95), while the bottom 10% had decreased risk (ORanxiety = 0.56; CI95% = 0.45—0.70; ORdepression = 0.58; CI95% = 0.45—0.74) compared to the remaining 90% of the distribution.ConclusionsPGSs can predict drug prescription for anxiety and depression in an independent sample.
|
|
| 7. |
- Tabrizi, Fara, et al.
(författare)
-
Prediction of anxiety and depression from polygenic scores in Swedish twins
- 2021
-
Ingår i: Abstracts of the WASAD Congress 2021. - : Springer. ; , s. 1802-1803
-
Konferensbidrag (refereegranskat)abstract
- Recent genome-wide association studies (GWAS) have identified several common variants associated with depression (Howard et al. 2019; Levey et al. 2021) and anxiety disorders (Levey et al. 2020; Meier et al. 2019; Purves et al. 2020), and these findings have been harnessed to develop polygenic scores (PGS) in order to provide an overall measure of individuals’ genetic liability to develop a disease (Torkamani et al. 2018). Research on the utility of PGSs as predictors of risk for disease is gaining traction, with studies on somatic illness showing that disease risk increases sharply in the right tail of the PGS distribution (Khera et al. 2018). Thus, PGS stratification could be of clinical relevance if it provides an opportunity to target those in need of preventive interventions with increased precision. The current potential of PGS stratification for depression and anxiety disorders remains an open question. In the current study, we applied 36 predefined PGSs from the polygenic index repository (Becker et al. 2021) on a target sample of 11,210 genotyped twins. Cases were defined as those with prescribed medication, where the prescription explicitly stated that a drug was ordinated for indication of depression or anxiety, respectively. Drugs included antidepressants (SSRI and SNRI), Benzodiazepines, Antihistamines, Buspirone, and Betablockers.
|
|
