| 1. |
|
|
| 2. |
- Bauzá-Thorbrügge, Marco, et al.
(författare)
-
Adiponectin stimulates Sca1+CD34−-adipocyte precursor cells associated with hyperplastic expansion and beiging of brown and white adipose tissue
- 2024
-
Ingår i: Metabolism. - : Elsevier. - 0026-0495 .- 1532-8600. ; 151
-
Tidskriftsartikel (refereegranskat)abstract
- Background: The adipocyte hormone adiponectin improves insulin sensitivity and there is an inverse correlation between adiponectin levels and type-2 diabetes risk. Previous research shows that adiponectin remodels the adipose tissue into a more efficient metabolic sink. For instance, mice that overexpress adiponectin show increased capacity for hyperplastic adipose tissue expansion as evident from smaller and metabolically more active white adipocytes. In contrast, the brown adipose tissue (BAT) of these mice looks “whiter” possibly indicating reduced metabolic activity. Here, we aimed to further establish the effect of adiponectin on adipose tissue expansion and adipocyte mitochondrial function as well as to unravel mechanistic aspects in this area. Methods: Brown and white adipose tissues from adiponectin overexpressing (APN tg) mice and littermate wildtype controls, housed at room and cold temperature, were studied by histological, gene/protein expression and flow cytometry analyses. Metabolic and mitochondrial functions were studied by radiotracers and Seahorse-based technology. In addition, mitochondrial function was assessed in cultured adiponectin deficient adipocytes from APN knockout and heterozygote mice. Results: APN tg BAT displayed increased proliferation prenatally leading to enlarged BAT. Postnatally, APN tg BAT turned whiter than control BAT, confirming previous reports. Furthermore, elevated adiponectin augmented the sympathetic innervation/activation within adipose tissue. APN tg BAT displayed reduced metabolic activity and reduced mitochondrial oxygen consumption rate (OCR). In contrast, APN tg inguinal white adipose tissue (IWAT) displayed enhanced metabolic activity. These metabolic differences between genotypes were apparent also in cultured adipocytes differentiated from BAT and IWAT stroma vascular fraction, and the OCR was reduced in both brown and white APN heterozygote adipocytes. In both APN tg BAT and IWAT, the mesenchymal stem cell-related genes were upregulated along with an increased abundance of Lineage−Sca1+CD34− “beige-like” adipocyte precursor cells. In vitro, the adiponectin receptor agonist Adiporon increased the expression of the proliferation marker Pcna and decreased the expression of Cd34 in Sca1+ mesenchymal stem cells. Conclusions: We propose that the seemingly opposite effect of adiponectin on BAT and IWAT is mediated by a common mechanism; while reduced adiponectin levels are linked to lower adipocyte OCR, elevated adiponectin levels stimulate expansion of adipocyte precursor cells that produce adipocytes with intrinsically higher metabolic rate than classical white but lower metabolic rate than classical brown adipocytes. Moreover, adiponectin can modify the adipocytes' metabolic activity directly and by enhancing the sympathetic innervation within a fat depot.
|
|
| 3. |
- Benrick, Anna, 1979, et al.
(författare)
-
Electroacupuncture mimics exercise-induced changes in skeletal muscle gene expression in polycystic ovary syndrome women.
- 2020
-
Ingår i: The Journal of clinical endocrinology and metabolism. - : The Endocrine Society. - 1945-7197 .- 0021-972X. ; 105:6, s. 2027-2041
-
Tidskriftsartikel (refereegranskat)abstract
- Autonomic nervous system activation mediates the increase in whole-body glucose uptake in response to electroacupuncture but the mechanisms are largely unknown.To identify the molecular mechanisms underlying electroacupuncture-induced glucose uptake in skeletal muscle in insulin-resistant overweight/obese women with and without polycystic ovary syndrome (PCOS).Participants: In a case-control study, skeletal muscle biopsies were collected from 15 women with PCOS and 14 controls before and after electroacupuncture. Gene expression and methylation was analyzed using Illumina BeadChips arrays.A single bout of electroacupuncture restores metabolic and transcriptional alterations and induces epigenetic changes in skeletal muscle. Transcriptomic analysis revealed 180 unique genes (q<0.05) whose expression was changed by electroacupuncture, with 95% of the changes towards a healthier phenotype. We identified DNA methylation changes at 304 unique sites (q<0.20), and these changes correlated with altered expression of 101 genes (p<0.05). Among the 50 most upregulated genes in response to electroacupuncture, 38% were also upregulated in response to exercise. We identified a subset of genes that were selectively altered by electroacupuncture in women with PCOS. For example, MSX1 and SRNX1 were decreased in muscle tissue of women with PCOS and were increased by electroacupuncture and exercise. siRNA-mediated silencing of these two genes in cultured myotubes decreased glycogen synthesis, supporting a role for these genes in glucose homeostasis.Our findings provide evidence that electroacupuncture normalizes gene expression in skeletal muscle in a manner similar to acute exercise. Electroacupuncture might therefore be a useful way of assisting those who have difficulties performing exercise.
|
|
| 4. |
- Benrick, Anna, 1979-, et al.
(författare)
-
Electroacupuncture mimics exercise-induced changes in skeletal muscle gene expression in women with polycystic ovary syndrome
- 2020
-
Ingår i: Journal of Clinical Endocrinology and Metabolism. - : Oxford University Press. - 0021-972X .- 1945-7197. ; 105:6, s. 2027-2041
-
Tidskriftsartikel (refereegranskat)abstract
- ContextAutonomic nervous system activation mediates the increase in whole-body glucose uptake in response to electroacupuncture but the mechanisms are largely unknown.ObjectiveTo identify the molecular mechanisms underlying electroacupuncture-induced glucose uptake in skeletal muscle in insulin-resistant overweight/obese women with and without polycystic ovary syndrome (PCOS).Design/ParticipantsIn a case-control study, skeletal muscle biopsies were collected from 15 women with PCOS and 14 controls before and after electroacupuncture. Gene expression and methylation was analyzed using Illumina BeadChips arrays.ResultsA single bout of electroacupuncture restores metabolic and transcriptional alterations and induces epigenetic changes in skeletal muscle. Transcriptomic analysis revealed 180 unique genes (q < 0.05) whose expression was changed by electroacupuncture, with 95% of the changes towards a healthier phenotype. We identified DNA methylation changes at 304 unique sites (q < 0.20), and these changes correlated with altered expression of 101 genes (P < 0.05). Among the 50 most upregulated genes in response to electroacupuncture, 38% were also upregulated in response to exercise. We identified a subset of genes that were selectively altered by electroacupuncture in women with PCOS. For example, MSX1 and SRNX1 were decreased in muscle tissue of women with PCOS and were increased by electroacupuncture and exercise. siRNA-mediated silencing of these 2 genes in cultured myotubes decreased glycogen synthesis, supporting a role for these genes in glucose homeostasis.ConclusionOur findings provide evidence that electroacupuncture normalizes gene expression in skeletal muscle in a manner similar to acute exercise. Electroacupuncture might therefore be a useful way of assisting those who have difficulties performing exercise.
|
|
| 5. |
- 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.
|
|
