136 results on '"Ahnmark A"'
Search Results
2. IDOL regulates systemic energy balance through control of neuronal VLDLR expression
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Lee, Stephen D, Priest, Christina, Bjursell, Mikael, Gao, Jie, Arneson, Douglas V, Ahn, In Sook, Diamante, Graciel, van Veen, J Edward, Massa, Megan G, Calkin, Anna C, Kim, Jason, Andersén, Harriet, Rajbhandari, Prashant, Porritt, Michelle, Carreras, Alba, Ahnmark, Andrea, Seeliger, Frank, Maxvall, Ingela, Eliasson, Pernilla, Althage, Magnus, Åkerblad, Peter, Lindén, Daniel, Cole, Tracy A, Lee, Richard, Boyd, Helen, Bohlooly-Y, Mohammad, Correa, Stephanie M, Yang, Xia, Tontonoz, Peter, and Hong, Cynthia
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Medical Biochemistry and Metabolomics ,Medical Physiology ,Biomedical and Clinical Sciences ,Nutrition and Dietetics ,Nutrition ,Genetics ,Digestive Diseases ,Liver Disease ,Obesity ,2.1 Biological and endogenous factors ,1.1 Normal biological development and functioning ,Oral and gastrointestinal ,Stroke ,Metabolic and endocrine ,Animals ,Blood Glucose ,Diet ,Energy Metabolism ,Hypothalamus ,Insulin Resistance ,Mice ,Mice ,Knockout ,Neurons ,Receptors ,LDL ,Ubiquitin-Protein Ligases ,Medical biochemistry and metabolomics ,Medical physiology ,Nutrition and dietetics - Abstract
Liver X receptors limit cellular lipid uptake by stimulating the transcription of Inducible Degrader of the LDL Receptor (IDOL), an E3 ubiquitin ligase that targets lipoprotein receptors for degradation. The function of IDOL in systemic metabolism is incompletely understood. Here we show that loss of IDOL in mice protects against the development of diet-induced obesity and metabolic dysfunction by altering food intake and thermogenesis. Unexpectedly, analysis of tissue-specific knockout mice revealed that IDOL affects energy balance, not through its actions in peripheral metabolic tissues (liver, adipose, endothelium, intestine, skeletal muscle), but by controlling lipoprotein receptor abundance in neurons. Single-cell RNA sequencing of the hypothalamus demonstrated that IDOL deletion altered gene expression linked to control of metabolism. Finally, we identify VLDLR rather than LDLR as the primary mediator of IDOL effects on energy balance. These studies identify a role for the neuronal IDOL-VLDLR pathway in metabolic homeostasis and diet-induced obesity.
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- 2019
3. TLCD1 and TLCD2 regulate cellular phosphatidylethanolamine composition and promote the progression of non-alcoholic steatohepatitis
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Petkevicius, Kasparas, Palmgren, Henrik, Glover, Matthew S., Ahnmark, Andrea, Andréasson, Anne-Christine, Madeyski-Bengtson, Katja, Kawana, Hiroki, Allman, Erik L., Kaper, Delaney, Uhrbom, Martin, Andersson, Liselotte, Aasehaug, Leif, Forsström, Johan, Wallin, Simonetta, Ahlstedt, Ingela, Leke, Renata, Karlsson, Daniel, González-King, Hernán, Löfgren, Lars, Nilsson, Ralf, Pellegrini, Giovanni, Kono, Nozomu, Aoki, Junken, Hess, Sonja, Sienski, Grzegorz, Pilon, Marc, Bohlooly-Y, Mohammad, Maresca, Marcello, and Peng, Xiao-Rong
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- 2022
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4. PPARγ and PPARα synergize to induce robust browning of white fat in vivo
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Kroon, Tobias, Harms, Matthew, Maurer, Stefanie, Bonnet, Laurianne, Alexandersson, Ida, Lindblom, Anna, Ahnmark, Andrea, Nilsson, Daniel, Gennemark, Peter, O'Mahony, Gavin, Osinski, Victoria, McNamara, Coleen, and Boucher, Jeremie
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- 2020
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5. Pnpla3 silencing with antisense oligonucleotides ameliorates nonalcoholic steatohepatitis and fibrosis in Pnpla3 I148M knock-in mice
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Lindén, Daniel, Ahnmark, Andrea, Pingitore, Piero, Ciociola, Ester, Ahlstedt, Ingela, Andréasson, Anne-Christine, Sasidharan, Kavitha, Madeyski-Bengtson, Katja, Zurek, Magdalena, Mancina, Rosellina M., Lindblom, Anna, Bjursell, Mikael, Böttcher, Gerhard, Ståhlman, Marcus, Bohlooly-Y, Mohammad, Haynes, William G., Carlsson, Björn, Graham, Mark, Lee, Richard, Murray, Sue, Valenti, Luca, Bhanot, Sanjay, Åkerblad, Peter, and Romeo, Stefano
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- 2019
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6. Pnpla3 silencing with antisense oligonucleotides ameliorates nonalcoholic steatohepatitis and fibrosis in Pnpla3 I148M knock-in mice
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Daniel Lindén, Andrea Ahnmark, Piero Pingitore, Ester Ciociola, Ingela Ahlstedt, Anne-Christine Andréasson, Kavitha Sasidharan, Katja Madeyski-Bengtson, Magdalena Zurek, Rosellina M. Mancina, Anna Lindblom, Mikael Bjursell, Gerhard Böttcher, Marcus Ståhlman, Mohammad Bohlooly-Y, William G. Haynes, Björn Carlsson, Mark Graham, Richard Lee, Sue Murray, Luca Valenti, Sanjay Bhanot, Peter Åkerblad, and Stefano Romeo
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Internal medicine ,RC31-1245 - Abstract
Objective: Nonalcoholic fatty liver disease (NAFLD) is becoming a leading cause of advanced chronic liver disease. The progression of NAFLD, including nonalcoholic steatohepatitis (NASH), has a strong genetic component, and the most robust contributor is the patatin-like phospholipase domain-containing 3 (PNPLA3) rs738409 encoding the 148M protein sequence variant. We hypothesized that suppressing the expression of the PNPLA3 148M mutant protein would exert a beneficial effect on the entire spectrum of NAFLD. Methods: We examined the effects of liver-targeted GalNAc3-conjugated antisense oligonucleotide (ASO)-mediated silencing of Pnpla3 in a knock-in mouse model in which we introduced the human PNPLA3 I148M mutation. Results: ASO-mediated silencing of Pnpla3 reduced liver steatosis (p = 0.038) in homozygous Pnpla3 148M/M knock-in mutant mice but not in wild-type littermates fed a steatogenic high-sucrose diet. In mice fed a NASH-inducing diet, ASO-mediated silencing of Pnpla3 reduced liver steatosis score and NAFLD activity score independent of the Pnpla3 genotype, while reductions in liver inflammation score (p = 0.018) and fibrosis stage (p = 0.031) were observed only in the Pnpla3 knock-in 148M/M mutant mice. These responses were accompanied by reduced liver levels of Mcp1 (p = 0.026) and Timp2 (p = 0.007) specifically in the mutant knock-in mice. This may reduce levels of chemokine attracting inflammatory cells and increase the collagenolytic activity during tissue regeneration. Conclusion: This study provides the first evidence that a Pnpla3 ASO therapy can improve all features of NAFLD, including liver fibrosis, and suppress the expression of a strong innate genetic risk factor, Pnpla3 148M, which may open up a precision medicine approach in NASH. Keywords: PNPLA3, NAFLD, NASH, Fibrosis, Liver
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- 2019
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7. PPARγ and PPARα synergize to induce robust browning of white fat in vivo
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Tobias Kroon, Matthew Harms, Stefanie Maurer, Laurianne Bonnet, Ida Alexandersson, Anna Lindblom, Andrea Ahnmark, Daniel Nilsson, Peter Gennemark, Gavin O'Mahony, Victoria Osinski, Coleen McNamara, and Jeremie Boucher
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Brown adipocytes ,Beige adipocytes ,Thermogenesis ,UCP1 ,FGF21 ,PPAR ,Internal medicine ,RC31-1245 - Abstract
Objective: Peroxisome proliferator-activated receptors (PPARs) are key transcription factors that regulate adipose development and function, and the conversion of white into brown-like adipocytes. Here we investigated whether PPARα and PPARγ activation synergize to induce the browning of white fat. Methods: A selection of PPAR activators was tested for their ability to induce the browning of both mouse and human white adipocytes in vitro, and in vivo in lean and obese mice. Results: All dual PPARα/γ activators tested robustly increased uncoupling protein 1 (Ucp1) expression in both mouse and human adipocytes in vitro, with tesaglitazar leading to the largest Ucp1 induction. Importantly, dual PPARα/γ activator tesaglitazar strongly induced browning of white fat in vivo in both lean and obese male mice at thermoneutrality, greatly exceeding the increase in Ucp1 observed with the selective PPARγ activator rosiglitazone. While selective PPARγ activation was sufficient for the conversion of white into brown-like adipocytes in vitro, dual PPARα/γ activation was superior to selective PPARγ activation at inducing white fat browning in vivo. Mechanistically, the superiority of dual PPARα/γ activators is mediated at least in part via a PPARα-driven increase in fibroblast growth factor 21 (FGF21). Combined treatment with rosiglitazone and FGF21 resulted in a synergistic increase in Ucp1 mRNA levels both in vitro and in vivo. Tesaglitazar-induced browning was associated with increased energy expenditure, enhanced insulin sensitivity, reduced liver steatosis, and an overall improved metabolic profile compared to rosiglitazone and vehicle control groups. Conclusions: PPARγ and PPARα synergize to induce robust browning of white fat in vivo, via PPARγ activation in adipose, and PPARα-mediated increase in FGF21.
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- 2020
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8. Inhibition of SGLT2 Preserves Function and Promotes Proliferation of Human Islets Cells In Vivo in Diabetic Mice
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Daniel Karlsson, Andrea Ahnmark, Alan Sabirsh, Anne-Christine Andréasson, Peter Gennemark, Ann-Sofie Sandinge, Lihua Chen, Björn Tyrberg, Daniel Lindén, and Maria Sörhede Winzell
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human islets ,transplantation ,insulin ,glucagon ,dapagliflozin ,diabetes ,Biology (General) ,QH301-705.5 - Abstract
Dapagliflozin is a sodium-glucose co-transporter 2 (SGLT2) inhibitor used for the treatment of diabetes. This study examines the effects of dapagliflozin on human islets, focusing on alpha and beta cell composition in relation to function in vivo, following treatment of xeno-transplanted diabetic mice. Mouse beta cells were ablated by alloxan, and dapagliflozin was provided in the drinking water while controls received tap water. Body weight, food and water intake, plasma glucose, and human C-peptide levels were monitored, and intravenous arginine/glucose tolerance tests (IVarg GTT) were performed to evaluate islet function. The grafted human islets were isolated at termination and stained for insulin, glucagon, Ki67, caspase 3, and PDX-1 immunoreactivity in dual and triple combinations. In addition, human islets were treated in vitro with dapagliflozin at different glucose concentrations, followed by insulin and glucagon secretion measurements. SGLT2 inhibition increased the animal survival rate and reduced plasma glucose, accompanied by sustained human C-peptide levels and improved islet response to glucose/arginine. SGLT2 inhibition increased both alpha and beta cell proliferation (Ki67+glucagon+ and Ki67+insulin+) while apoptosis was reduced (caspase3+glucagon+ and caspase3+insulin+). Alpha cells were fewer following inhibition of SGLT2 with increased glucagon/PDX-1 double-positive cells, a marker of alpha to beta cell transdifferentiation. In vitro treatment of human islets with dapagliflozin had no apparent impact on islet function. In summary, SGLT2 inhibition supported human islet function in vivo in the hyperglycemic milieu and potentially promoted alpha to beta cell transdifferentiation, most likely through an indirect mechanism.
- Published
- 2022
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9. Human genetics uncovers MAP3K15 as an obesity-independent therapeutic target for diabetes
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Abhishek Nag, Ryan S. Dhindsa, Jonathan Mitchell, Chirag Vasavda, Andrew R. Harper, Dimitrios Vitsios, Andrea Ahnmark, Bilada Bilican, Katja Madeyski-Bengtson, Bader Zarrouki, Anthony W. Zoghbi, Quanli Wang, Katherine R. Smith, Jesus Alegre-Díaz, Pablo Kuri-Morales, Jaime Berumen, Roberto Tapia-Conyer, Jonathan Emberson, Jason M. Torres, Rory Collins, David M. Smith, Benjamin Challis, Dirk S. Paul, Mohammad Bohlooly-Y, Mike Snowden, David Baker, Regina Fritsche-Danielson, Menelas N. Pangalos, and Slavé Petrovski
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Multidisciplinary - Abstract
We performed collapsing analyses on 454,796 UK Biobank (UKB) exomes to detect gene-level associations with diabetes. Recessive carriers of nonsynonymous variants in MAP3K15 were 30% less likely to develop diabetes ( P = 5.7 × 10 −10 ) and had lower glycosylated hemoglobin (β = −0.14 SD units, P = 1.1 × 10 −24 ). These associations were independent of body mass index, suggesting protection against insulin resistance even in the setting of obesity. We replicated these findings in 96,811 Admixed Americans in the Mexico City Prospective Study ( P < 0.05)Moreover, the protective effect of MAP3K15 variants was stronger in individuals who did not carry the Latino-enriched SLC16A11 risk haplotype ( P = 6.0 × 10 −4 ). Separately, we identified a Finnish-enriched MAP3K15 protein-truncating variant associated with decreased odds of both type 1 and type 2 diabetes ( P < 0.05) in FinnGen. No adverse phenotypes were associated with protein-truncating MAP3K15 variants in the UKB, supporting this gene as a therapeutic target for diabetes.
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- 2023
10. Elevated Adipocyte Membrane Phospholipid Saturation Does Not Compromise Insulin Signaling.
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Palmgren, Henrik, Petkevicius, Kasparas, Bartesaghi, Stefano, Ahnmark, Andrea, Ruiz, Mario, Nilsson, Ralf, Löfgren, Lars, Glover, Matthew S., Andréasson, Anne-Christine, Andersson, Liselotte, Becquart, Cécile, Kurczy, Michael, Kull, Bengt, Wallin, Simonetta, Karlsson, Daniel, Hess, Sonja, Maresca, Marcello, Bohlooly-Y, Mohammad, Peng, Xiao-Rong, and Pilon, Marc
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WHITE adipose tissue ,FAT cells ,SATURATED fatty acids ,INSULIN ,PALMITIC acid - Abstract
Increased saturated fatty acid (SFA) levels in membrane phospholipids have been implicated in the development of metabolic disease. Here, we tested the hypothesis that increased SFA content in cell membranes negatively impacts adipocyte insulin signaling. Preadipocyte cell models with elevated SFA levels in phospholipids were generated by disrupting the ADIPOR2 locus, which resulted in a striking twofold increase in SFA-containing phosphatidylcholines and phosphatidylethanolamines, which persisted in differentiated adipocytes. Similar changes in phospholipid composition were observed in white adipose tissues isolated from the ADIPOR2-knockout mice. The SFA levels in phospholipids could be further increased by treating ADIPOR2-deficient cells with palmitic acid and resulted in reduced membrane fluidity and endoplasmic reticulum stress in mouse and human preadipocytes. Strikingly, increased SFA levels in differentiated adipocyte phospholipids had no effect on adipocyte gene expression or insulin signaling in vitro. Similarly, increased adipocyte phospholipid saturation did not impair white adipose tissue function in vivo, even in mice fed a high-saturated fat diet at thermoneutrality. We conclude that increasing SFA levels in adipocyte phospholipids is well tolerated and does not affect adipocyte insulin signaling in vitro and in vivo. [ABSTRACT FROM AUTHOR]
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- 2023
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11. ELEVATED ADIPOCYTE MEMBRANE PHOSPHOLIPID SATURATION DOES NOT COMPROMISE INSULIN SIGNALING
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Palmgren, Henrik, primary, Petkevicius, Kasparas, primary, Bartesaghi, Stefano, primary, Ahnmark, Andrea, primary, Ruiz, Mario, primary, Nilsson, Ralf, primary, Löfgren, Lars, primary, Glover, Matthew S., primary, Andréasson, Anne-Christine, primary, Andersson, Liselotte, primary, Becquart, Cécile, primary, Kurczy, Michael, primary, Kull, Bengt, primary, Wallin, Simonetta, primary, Karlsson, Daniel, primary, Hess, Sonja, primary, Maresca, Marcello, primary, Bohlooly-Y, Mohammad, primary, Peng, Xiao-Rong, primary, and Pilon, Marc, primary
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- 2023
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12. Studies of Nontarget-Mediated Distribution of Human Full-Length IgG1 Antibody and Its FAb Fragment in Cardiovascular and Metabolic-Related Tissues
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Davidsson, Pia, Söderling, Ann-Sofi, Svensson, Lena, Ahnmark, Andrea, Flodin, Christine, Wanag, Ewa, Screpanti-Sundqvist, Valentina, and Gennemark, Peter
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- 2015
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13. Elevated Adipocyte Membrane Phospholipid Saturation Does not Compromise Insulin Signaling
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Palmgren, Henrik, primary, Petkevicius, Kasparas, additional, Bartesaghi, Stefano, additional, Ahnmark, Andrea, additional, Ruiz, Mario, additional, Nilsson, Ralf, additional, Löfgren, Lars, additional, Glover, Matthew S., additional, Andréasson, Anne-Christine, additional, Andersson, Liselotte, additional, Becquart, Cécile, additional, Kurczy, Michael, additional, Kull, Bengt, additional, Wallin, Simonetta, additional, Karlsson, Daniel, additional, Hess, Sonja, additional, Maresca, Marcello, additional, Bohlooly-Y, Mohammad, additional, Peng, Xiao-Rong, additional, and Pilon, Marc, additional
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- 2022
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14. ELEVATED ADIPOCYTE MEMBRANE PHOSPHOLIPID SATURATION DOES NOT COMPROMISE INSULIN SIGNALING
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Henrik, Palmgren, Kasparas, Petkevicius, Stefano, Bartesaghi, Andrea, Ahnmark, Mario, Ruiz, Ralf, Nilsson, Lars, Löfgren, Matthew S, Glover, Anne-Christine, Andréasson, Liselotte, Andersson, Cécile, Becquart, Michael, Kurczy, Bengt, Kull, Simonetta, Wallin, Daniel, Karlsson, Sonja, Hess, Marcello, Maresca, Mohammad, Bohlooly-Y, Xiao-Rong, Peng, and Marc, Pilon
- Subjects
Endocrinology, Diabetes and Metabolism ,Internal Medicine - Abstract
Increased saturated fatty acid levels in membrane phospholipids have been implicated in the development of metabolic disease. Here, we tested the hypothesis that increased saturated fatty acid (SFA) content in cell membranes negatively impacts adipocyte insulin signaling. Pre-adipocyte cell models with elevated SFA levels in phospholipids were generated by disrupting the ADIPOR2 locus, which resulted in a striking two-fold increase in SFA-containing phosphatidylcholines and phosphatidylethanolamines, which persisted in differentiated adipocytes. Similar changes in phospholipid composition were observed in white adipose tissues isolated from the ADIPOR2 knockout mice. The SFA levels in phospholipids could be further increased by treating ADIPOR2-deficient cells with palmitic acid and resulted in reduced membrane fluidity and endoplasmic reticulum stress in mouse and human pre-adipocytes. Strikingly, increased SFA levels in differentiated adipocyte phospholipids had no effect on adipocyte gene expression or insulin signaling in vitro. Similarly, increased adipocyte phospholipid saturation did not impair white adipose tissue function in vivo, even in mice fed a high saturated fat diet at thermoneutrality. We conclude that increasing SFA levels in adipocyte phospholipids is well tolerated and does not affect adipocyte insulin signaling in vitro and in vivo.
- Published
- 2023
15. Secretagogin is increased in plasma from type 2 diabetes patients and potentially reflects stress and islet dysfunction.
- Author
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Sara F Hansson, Alex-Xianghua Zhou, Paulina Vachet, Jan W Eriksson, Maria J Pereira, Stanko Skrtic, Helen Jongsma Wallin, Anders Ericsson-Dahlstrand, Daniel Karlsson, Andrea Ahnmark, Maria Sörhede Winzell, Maria Chiara Magnone, and Pia Davidsson
- Subjects
Medicine ,Science - Abstract
Beta cell dysfunction accompanies and drives the progression of type 2 diabetes mellitus (T2D), but there are few clinical biomarkers available to assess islet cell stress in humans. Secretagogin, a protein enriched in pancreatic islets, demonstrates protective effects on beta cell function in animals. However, its potential as a circulating biomarker released from human beta cells and islets has not been studied. In this study primary human islets, beta cells and plasma samples were used to explore secretion and expression of secretagogin in relation to the T2D pathology. Secretagogin was abundantly and specifically expressed and secreted from human islets. Furthermore, T2D patients had an elevated plasma level of secretagogin compared with matched healthy controls, which was confirmed in plasma of diabetic mice transplanted with human islets. Additionally, the plasma secretagogin level of the human cohort had an inverse correlation to clinical assessments of beta cell function. To explore the mechanism of secretagogin release in vitro, human beta cells (EndoC-βH1) were exposed to elevated glucose or cellular stress-inducing agents. Secretagogin was not released in parallel with glucose stimulated insulin release, but was markedly elevated in response to endoplasmic reticulum stressors and cytokines. These findings indicate that secretagogin is a potential novel biomarker, reflecting stress and islet cell dysfunction in T2D patients.
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- 2018
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16. Human genetics uncovers
- Author
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Abhishek, Nag, Ryan S, Dhindsa, Jonathan, Mitchell, Chirag, Vasavda, Andrew R, Harper, Dimitrios, Vitsios, Andrea, Ahnmark, Bilada, Bilican, Katja, Madeyski-Bengtson, Bader, Zarrouki, Anthony W, Zoghbi, Quanli, Wang, Katherine R, Smith, Jesus, Alegre-Díaz, Pablo, Kuri-Morales, Jaime, Berumen, Roberto, Tapia-Conyer, Jonathan, Emberson, Jason M, Torres, Rory, Collins, David M, Smith, Benjamin, Challis, Dirk S, Paul, Mohammad, Bohlooly-Y, Mike, Snowden, David, Baker, Regina, Fritsche-Danielson, Menelas N, Pangalos, and Slavé, Petrovski
- Subjects
Monocarboxylic Acid Transporters ,Diabetes Mellitus, Type 2 ,Humans ,Genetic Predisposition to Disease ,Obesity ,Prospective Studies ,MAP Kinase Kinase Kinases - Abstract
We performed collapsing analyses on 454,796 UK Biobank (UKB) exomes to detect gene-level associations with diabetes. Recessive carriers of nonsynonymous variants in
- Published
- 2022
17. Human genetics uncovers MAP3K15 as an obesity-independent therapeutic target for diabetes
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Nag, Abhishek, primary, Dhindsa, Ryan S., additional, Mitchell, Jonathan, additional, Vasavda, Chirag, additional, Harper, Andrew R., additional, Vitsios, Dimitrios, additional, Ahnmark, Andrea, additional, Bilican, Bilada, additional, Madeyski-Bengtson, Katja, additional, Zarrouki, Bader, additional, Zoghbi, Anthony W., additional, Wang, Quanli, additional, Smith, Katherine R., additional, Alegre-Díaz, Jesus, additional, Kuri-Morales, Pablo, additional, Berumen, Jaime, additional, Tapia-Conyer, Roberto, additional, Emberson, Jonathan, additional, Torres, Jason M., additional, Collins, Rory, additional, Smith, David M., additional, Challis, Benjamin, additional, Paul, Dirk S., additional, Bohlooly-Y, Mohammad, additional, Snowden, Mike, additional, Baker, David, additional, Fritsche-Danielson, Regina, additional, Pangalos, Menelas N., additional, and Petrovski, Slavé, additional
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- 2022
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18. The acute glucose lowering effect of specific GPR120 activation in mice is mainly driven by glucagon-like peptide 1.
- Author
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Linda Sundström, Susanna Myhre, Monika Sundqvist, Andrea Ahnmark, William McCoull, Piotr Raubo, Sam D Groombridge, Magnus Polla, Ann-Christin Nyström, Lisbeth Kristensson, Mats Någård, and Maria Sörhede Winzell
- Subjects
Medicine ,Science - Abstract
The mechanism behind the glucose lowering effect occurring after specific activation of GPR120 is not completely understood. In this study, a potent and selective GPR120 agonist was developed and its pharmacological properties were compared with the previously described GPR120 agonist Metabolex-36. Effects of both compounds on signaling pathways and GLP-1 secretion were investigated in vitro. The acute glucose lowering effect was studied in lean wild-type and GPR120 null mice following oral or intravenous glucose tolerance tests. In vitro, in GPR120 overexpressing cells, both agonists signaled through Gαq, Gαs and the β-arrestin pathway. However, in mouse islets the signaling pathway was different since the agonists reduced cAMP production. The GPR120 agonists stimulated GLP-1 secretion both in vitro in STC-1 cells and in vivo following oral administration. In vivo GPR120 activation induced significant glucose lowering and increased insulin secretion after intravenous glucose administration in lean mice, while the agonists had no effect in GPR120 null mice. Exendin 9-39, a GLP-1 receptor antagonist, abolished the GPR120 induced effects on glucose and insulin following an intravenous glucose challenge. In conclusion, GLP-1 secretion is an important mechanism behind the acute glucose lowering effect following specific GPR120 activation.
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- 2017
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19. Input estimation for drug discovery using optimal control and Markov chain Monte Carlo approaches
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Trägårdh, Magnus, Chappell, Michael J., Ahnmark, Andrea, Lindén, Daniel, Evans, Neil D., and Gennemark, Peter
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- 2016
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20. Inhibition of SGLT2 Preserves Function and Promotes Proliferation of Human Islets Cells In Vivo in Diabetic Mice
- Author
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Karlsson, Daniel, Ahnmark, Andrea, Sabirsh, Alan, Andreasson, Anne-Christine, Gennemark, Peter, Sandinge, Ann-Sofie, Chen, Lihua, Tyrberg, Björn, Linden, Daniel, Winzell, Maria Sörhede, Karlsson, Daniel, Ahnmark, Andrea, Sabirsh, Alan, Andreasson, Anne-Christine, Gennemark, Peter, Sandinge, Ann-Sofie, Chen, Lihua, Tyrberg, Björn, Linden, Daniel, and Winzell, Maria Sörhede
- Abstract
Dapagliflozin is a sodium-glucose co-transporter 2 (SGLT2) inhibitor used for the treatment of diabetes. This study examines the effects of dapagliflozin on human islets, focusing on alpha and beta cell composition in relation to function in vivo, following treatment of xeno-transplanted diabetic mice. Mouse beta cells were ablated by alloxan, and dapagliflozin was provided in the drinking water while controls received tap water. Body weight, food and water intake, plasma glucose, and human C-peptide levels were monitored, and intravenous arginine/glucose tolerance tests (IVarg GTT) were performed to evaluate islet function. The grafted human islets were isolated at termination and stained for insulin, glucagon, Ki67, caspase 3, and PDX-1 immunoreactivity in dual and triple combinations. In addition, human islets were treated in vitro with dapagliflozin at different glucose concentrations, followed by insulin and glucagon secretion measurements. SGLT2 inhibition increased the animal survival rate and reduced plasma glucose, accompanied by sustained human C-peptide levels and improved islet response to glucose/arginine. SGLT2 inhibition increased both alpha and beta cell proliferation (Ki67(+)glucagon(+) and Ki67(+)insulin(+)) while apoptosis was reduced (caspase3(+)glucagon(+) and caspase3(+)insulin(+)). Alpha cells were fewer following inhibition of SGLT2 with increased glucagon/PDX-1 double-positive cells, a marker of alpha to beta cell transdifferentiation. In vitro treatment of human islets with dapagliflozin had no apparent impact on islet function. In summary, SGLT2 inhibition supported human islet function in vivo in the hyperglycemic milieu and potentially promoted alpha to beta cell transdifferentiation, most likely through an indirect mechanism., Funding Agencies|AstraZeneca ABAstraZeneca
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- 2022
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21. Hyperglycemia Induced by Glucokinase Deficiency Accelerates Atherosclerosis Development and Impairs Lesion Regression in Combined Heterozygous Glucokinase and the Apolipoprotein E-Knockout Mice
- Author
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Damilola D. Adingupu, Suvi E. Heinonen, Anne-Christine Andréasson, Mikael Brusberg, Andrea Ahnmark, Margareta Behrendt, Brendan Leighton, and Ann-Cathrine Jönsson-Rylander
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Diseases of the endocrine glands. Clinical endocrinology ,RC648-665 - Abstract
Aim. Models combining diabetes and atherosclerosis are important in evaluating the cardiovascular (CV) effects and safety of antidiabetes drugs in the development of treatments targeting CV complications. Our aim was to evaluate if crossing the heterozygous glucokinase knockout mouse (GK+/−) and hyperlipidemic mouse deficient in apolipoprotein E (ApoE−/−) will generate a disease model exhibiting a diabetic and macrovascular phenotype. Methods. The effects of defective glucokinase on the glucose metabolism and on the progression and regression of atherosclerosis on high-fat diets were studied in both genders of GK+/−ApoE−/− and ApoE−/− mice. Coronary vascular function of the female GK+/−ApoE−/− and ApoE−/− mice was also investigated. Results. GK+/−ApoE−/− mice show a stable hyperglycemia which was increased on Western diet. In oral glucose tolerance test, GK+/−ApoE−/− mice showed significant glucose intolerance and impaired glucose-stimulated insulin secretion. Plasma lipids were comparable with ApoE−/− mice; nevertheless the GK+/−ApoE−/− mice showed slightly increased atherosclerosis development. Conclusions. The GK+/−ApoE−/− mice showed a stable and reproducible hyperglycemia, accelerated atherosclerotic lesion progression, and no lesion regression after lipid lowering. This novel model provides a promising tool for drug discovery, enabling the evaluation of compound effects against both diabetic and cardiovascular endpoints simultaneously in one animal model.
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- 2016
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22. Inhibition of SGLT2 Preserves Function and Promotes Proliferation of Human Islets Cells In Vivo in Diabetic Mice
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Karlsson, Daniel, primary, Ahnmark, Andrea, additional, Sabirsh, Alan, additional, Andréasson, Anne-Christine, additional, Gennemark, Peter, additional, Sandinge, Ann-Sofie, additional, Chen, Lihua, additional, Tyrberg, Björn, additional, Lindén, Daniel, additional, and Sörhede Winzell, Maria, additional
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- 2022
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23. Human genetic evidence supports MAP3K15 inhibition as a therapeutic strategy for diabetes
- Author
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Benjamin Challis, Andrew R. Harper, David J. Smith, Menelas N. Pangalos, Mohammad Bohlooly-Y, Katherine R. Smith, Bader Zarrouki, Katja Madeyski-Bengtson, Dirk S. Paul, David Baker, Bilada Bilican, Andrea Ahnmark, Dimitrios Vitsios, Abhishek Nag, Mike Snowden, Regina Fritsche-Danielson, Quanli Wang, Ryan S. Dhindsa, and Slavé Petrovski
- Subjects
Nonsynonymous substitution ,business.industry ,Diabetes mellitus ,Health condition ,medicine ,Adult population ,medicine.disease ,business ,Bioinformatics ,Exome ,Biobank ,Therapeutic strategy ,HNF1A - Abstract
Diabetes mellitus is a chronic health condition that can result in significant end-organ complications and is estimated to impact at least 8.5% of the global adult population. Here, we performed gene-level collapsing analysis on exome sequences from 454,796 multi-ancestry UK Biobank participants to detect genetic associations with diabetes. Rare non-synonymous variants in GCK, GIGYF1, HNF1A, and HNF4A were significantly associated (P-8) with increased risk of diabetes, whereas rare non-synonymous variants in MAP3K15 were significantly associated with reduced risk of diabetes. Recessive carriers of rare non-synonymous variants in the X chromosome gene MAP3K15 had a 30% reduced risk of diabetes (OR=0.70, 95% CI: [0.62,0.79], P=5.7×10-10), along with reduced blood glucose (beta=-0.13, 95% CI: [-0.15,-0.10], P=5.5×10-18) and reduced glycosylated haemoglobin levels (beta=-0.14, 95% CI: [-0.16,-0.11], P=1.1×10-24). Hemizygous males carrying protein-truncating variants (PTVs) in MAP3K15 demonstrated a 40% reduced risk of diabetes (OR=0.60, 95% CI: [0.45,0.81], P=0.0007). These findings were independently replicated in FinnGen, with a MAP3K15 PTV associating with decreased risk of both type 1 diabetes (T1DM) and type 2 diabetes (T2DM) (pMAP3K15 loss on diabetes was independent of body mass index, suggesting its protective effect is unlikely to be mediated via the insulin resistance pathway. Tissue expression profile of MAP3K15 indicates a possible involvement of pancreatic islet cell or stress response pathways. No safety concerns were identified among heterozygous or recessive MAP3K15 PTV carriers across over 15,719 studied endpoints in the UK Biobank. Human population genetic evidence supports MAP3K15 inhibition as a novel therapeutic target for diabetes.
- Published
- 2021
24. PPARα activation increases triglyceride mass and adipose differentiation-related protein in hepatocytes
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Ulrika Edvardsson, Anna Ljungberg, Daniel Lindén, Lena William-Olsson, Helena Peilot-Sjögren, Andrea Ahnmark, and Jan Oscarsson
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Wy14,643 ,primary hepatocytes ,triglyceride synthesis ,fatty acid oxidation ,triglyceride secretion ,apolipoprotein B-100 ,Biochemistry ,QD415-436 - Abstract
Adipose differentiation-related protein (ADRP) is a lipid droplet-associated protein that is expressed in various tissues. In mice treated with the peroxisome proliferator-activated receptor α (PPARα) agonist Wy14,643 (Wy), hepatic mRNA and protein levels of ADRP as well as hepatic triglyceride content increased. Also in primary mouse hepatocytes, Wy increased ADRP expression and intracellular triglyceride mass. The triglyceride mass increased in spite of unchanged triglyceride biosynthesis and increased palmitic acid oxidation. However, Wy incubation decreased the secretion of newly synthesized triglycerides, whereas apolipoprotein B secretion increased. Thus, decreased availability of triglycerides for VLDL assembly could help to explain the cellular accumulation of triglycerides after Wy treatment. We hypothesized that this effect could be mediated by increased ADRP expression. Similar to PPARα activation, adenovirus-mediated ADRP overexpression in mouse hepatocytes enhanced cellular triglyceride mass and decreased the secretion of newly synthesized triglycerides. In ADRP-overexpressing cells, Wy incubation resulted in a further decrease in triglyceride secretion. This effect of Wy was not attributable to decreased cellular triglycerides after increased fatty acid oxidation because the triglyceride mass in Wy-treated ADRP-overexpressing cells was unchanged. In summary, PPARα activation prevents the availability of triglycerides for VLDL assembly and increases hepatic triglyceride content in part by increasing the expression of ADRP.
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- 2006
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25. Human genetic evidence supports MAP3K15 inhibition as a therapeutic strategy for diabetes
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Nag, Abhishek, primary, Dhindsa, Ryan S., additional, Harper, Andrew R., additional, Vitsios, Dimitrios, additional, Ahnmark, Andrea, additional, Bilican, Bilada, additional, Madeyski-Bengtson, Katja, additional, Zarrouki, Bader, additional, Wang, Quanli, additional, Smith, Katherine, additional, Smith, Dave, additional, Challis, Benjamin, additional, Paul, Dirk S., additional, Bohlooly-Y, Mohammad, additional, Snowden, Mike, additional, Baker, David, additional, Fritsche-Danielson, Regina, additional, Pangalos, Menelas N., additional, and Petrovski, Slavé, additional
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- 2021
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26. Monoclonal antibody targeting of fibroblast growth factor receptor 1c ameliorates obesity and glucose intolerance via central mechanisms.
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Christopher J Lelliott, Andrea Ahnmark, Therese Admyre, Ingela Ahlstedt, Lorraine Irving, Feenagh Keyes, Laurel Patterson, Michael B Mumphrey, Mikael Bjursell, Tracy Gorman, Mohammad Bohlooly-Y, Andrew Buchanan, Paula Harrison, Tristan Vaughan, Hans-Rudolf Berthoud, and Daniel Lindén
- Subjects
Medicine ,Science - Abstract
We have generated a novel monoclonal antibody targeting human FGFR1c (R1c mAb) that caused profound body weight and body fat loss in diet-induced obese mice due to decreased food intake (with energy expenditure unaltered), in turn improving glucose control. R1c mAb also caused weight loss in leptin-deficient ob/ob mice, leptin receptor-mutant db/db mice, and in mice lacking either the melanocortin 4 receptor or the melanin-concentrating hormone receptor 1. In addition, R1c mAb did not change hypothalamic mRNA expression levels of Agrp, Cart, Pomc, Npy, Crh, Mch, or Orexin, suggesting that R1c mAb could cause food intake inhibition and body weight loss via other mechanisms in the brain. Interestingly, peripherally administered R1c mAb accumulated in the median eminence, adjacent arcuate nucleus and in the circumventricular organs where it activated the early response gene c-Fos. As a plausible mechanism and coinciding with the initiation of food intake suppression, R1c mAb induced hypothalamic expression levels of the cytokines Monocyte chemoattractant protein 1 and 3 and ERK1/2 and p70 S6 kinase 1 activation.
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- 2014
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27. Adiponectin receptor 2 deficiency results in reduced atherosclerosis in the brachiocephalic artery in apolipoprotein E deficient mice.
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Anna Lindgren, Malin Levin, Sandra Rodrigo Blomqvist, Johannes Wikström, Andrea Ahnmark, Christina Mogensen, Gerhard Böttcher, Mohammad Bohlooly-Y, Jan Borén, Li-Ming Gan, and Daniel Lindén
- Subjects
Medicine ,Science - Abstract
Adiponectin has been shown to have beneficial cardiovascular effects and to signal through the adiponectin receptors, AdipoR1 and AdipoR2. The original aim of this study was to investigate the effect of combined AdipoR1 and AdipoR2 deficiency (AdipoR1(-/-)AdipoR2(-/-)) on atherosclerosis. However, we made the interesting observation that AdipoR1(-/-) AdipoR2(-/-) leads to embryonic lethality demonstrating the critical importance of the adiponectin signalling system during development. We then investigated the effect of AdipoR2-ablation on the progression of atherosclerosis in apolipoprotein E deficient (ApoE(-/-)) mice. AdipoR2(-/-)ApoE(-/-) mice fed an atherogenic diet had decreased plaque area in the brachiocephalic artery compared with AdipoR2(+/+) ApoE(-/-) littermate controls as visualized in vivo using an ultrasound biomicroscope and confirmed by histological analyses. The decreased plaque area in the brachiocephalic artery could not be explained by plasma cholesterol levels or inflammatory status. However, accumulation of neutral lipids was decreased in peritoneal macrophages from AdipoR2(-/-)ApoE(-/-) mice after incubation with oxidized LDL. This effect was associated with lower CD36 and higher ABCA1 mRNA levels in peritoneal macrophages from AdipoR2(-/-)ApoE(-/-) mice compared with AdipoR2(+/+)ApoE(-/-) controls after incubation with oxidized LDL. In summary, we show that adiponectin receptors are crucial during embryonic development and that AdipoR2-deficiency slows down the progression of atherosclerosis in the brachiocephalic artery of ApoE-deficient mice.
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- 2013
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28. PPARγ and PPARα synergize to induce robust browning of white fat in vivo
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Anna Lindblom, Andrea Ahnmark, Matthew J. Harms, Stefanie Maurer, Tobias Kroon, Laurianne Bonnet, Daniel Nilsson, Victoria Osinski, Jeremie Boucher, Ida Alexandersson, Peter Gennemark, Gavin O'Mahony, and Coleen A. McNamara
- Subjects
0301 basic medicine ,Male ,FGF21 ,Adipocytes, White ,Peroxisome proliferator-activated receptor ,Adipose tissue ,FGF21, fibroblast growth factor 21 ,White adipose tissue ,PPAR ,chemistry.chemical_compound ,Mice ,0302 clinical medicine ,iWAT, inguinal WAT ,Adipose Tissue, Brown ,iBAT, interscapular BAT ,Uncoupling Protein 1 ,chemistry.chemical_classification ,Brown adipocytes ,Thermogenesis ,WAT, white adipose tissue ,TG, triglycerides ,TN, thermoneutrality ,Thermogenin ,DIO, diet-induced obese ,Adipocytes, Brown ,RT, room temperature ,Original Article ,TZD, thiazolidinedione ,Rosiglitazone ,medicine.drug ,medicine.medical_specialty ,lcsh:Internal medicine ,UCP1 ,Tesaglitazar ,Adipose Tissue, White ,030209 endocrinology & metabolism ,QUICKI, quantitative insulin-sensitivity check index ,eWAT, epididymal WAT ,PPAR, peroxisome proliferator-activated receptors ,03 medical and health sciences ,Beige adipocytes ,Internal medicine ,UCP1, uncoupling protein 1 ,medicine ,Animals ,PPAR alpha ,lcsh:RC31-1245 ,Molecular Biology ,Activator (genetics) ,EE, energy expenditure ,Cell Biology ,BAT, brown adipose tissue ,Mice, Inbred C57BL ,PPAR gamma ,030104 developmental biology ,Endocrinology ,chemistry ,Energy Metabolism ,Transcription Factors - Abstract
Objective Peroxisome proliferator-activated receptors (PPARs) are key transcription factors that regulate adipose development and function, and the conversion of white into brown-like adipocytes. Here we investigated whether PPARα and PPARγ activation synergize to induce the browning of white fat. Methods A selection of PPAR activators was tested for their ability to induce the browning of both mouse and human white adipocytes in vitro, and in vivo in lean and obese mice. Results All dual PPARα/γ activators tested robustly increased uncoupling protein 1 (Ucp1) expression in both mouse and human adipocytes in vitro, with tesaglitazar leading to the largest Ucp1 induction. Importantly, dual PPARα/γ activator tesaglitazar strongly induced browning of white fat in vivo in both lean and obese male mice at thermoneutrality, greatly exceeding the increase in Ucp1 observed with the selective PPARγ activator rosiglitazone. While selective PPARγ activation was sufficient for the conversion of white into brown-like adipocytes in vitro, dual PPARα/γ activation was superior to selective PPARγ activation at inducing white fat browning in vivo. Mechanistically, the superiority of dual PPARα/γ activators is mediated at least in part via a PPARα-driven increase in fibroblast growth factor 21 (FGF21). Combined treatment with rosiglitazone and FGF21 resulted in a synergistic increase in Ucp1 mRNA levels both in vitro and in vivo. Tesaglitazar-induced browning was associated with increased energy expenditure, enhanced insulin sensitivity, reduced liver steatosis, and an overall improved metabolic profile compared to rosiglitazone and vehicle control groups. Conclusions PPARγ and PPARα synergize to induce robust browning of white fat in vivo, via PPARγ activation in adipose, and PPARα-mediated increase in FGF21., Graphical abstract Dual PPARα/γ activation is superior to selective PPARγ activation at inducing browning of white fat in vivo: via PPARγ action in the adipose and a PPARα-mediated action in the liver resulting in increased circulating fibroblast growth factor 21 (FGF21).Image 1, Highlights • Dual PPARα/γ activators robustly induce browning of white fat in vitro and in vivo. • PPARγ action alone is sufficient to convert white into brown-like adipocytes in vitro. • Dual PPARα/γ activators are superior to PPARγ activators for browning of white fat in vivo. • PPARγ action in adipose and PPARα-mediated increase in FGF21 synergize to induce browning of white fat in vivo.
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- 2020
29. Monoclonal antibody targeting of fibroblast growth factor receptor 1c causes cardiac valvulopathy in rats
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Andrew Buchanan, Sally Price, Rakesh Dixit, Pia Davidsson, Lorraine Irving, Jean-Martin Lapointe, Feenagh Keyes, Andrea Ahnmark, Lolke de Haan, Nicholas Buss, and Daniel Lindén
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Male ,0301 basic medicine ,Pathology ,medicine.medical_specialty ,animal structures ,Fenfluramine ,medicine.drug_class ,Heart Valve Diseases ,In situ hybridization ,Toxicology ,Fibroblast growth factor ,Monoclonal antibody ,Bone and Bones ,Pathogenesis ,Eating ,03 medical and health sciences ,Osteogenesis ,Weight Loss ,medicine ,Animals ,Receptor, Fibroblast Growth Factor, Type 4 ,RNA, Messenger ,Receptor, Fibroblast Growth Factor, Type 1 ,Rats, Wistar ,Receptor ,Pharmacology ,business.industry ,Fibroblast growth factor receptor 1 ,Antibodies, Monoclonal ,Heart Valves ,Rats ,030104 developmental biology ,Fibroblast growth factor receptor ,Anti-Obesity Agents ,business ,medicine.drug - Abstract
Fibroblast Growth Factors (FGFs) and their receptors (FGFRs) have been proposed as potential drug targets for the treatment of obesity. The aim of this study was to assess the potential toxicity in rats of three anti-FGFR1c mAbs with differential binding activity prior to clinical development. Groups of male rats received weekly injections of either one of two FGFR1c-specific mAbs or an FGFR1c/FGFR4-specific mAb at 10 mg/kg for up to 4 weeks. All three mAbs caused significant reductions in food intake and weight loss leading to some animals being euthanized early for welfare reasons. In all three groups given these mAbs, microscopic changes were seen in the bones and heart valves. In the bones of the femoro-tibial joint, thickening of the diaphyseal cortex of long bones, due to deposition of well organized new lamellar bone, indicated that an osteogenic effect was observed. In the heart, valvulopathy described as an endocardial myxomatous change affecting the mitral, pulmonary, tricuspid and aortic valves was observed in all mAb-treated animals. The presence of FGFR1 mRNA expression in the heart valves was confirmed using in situ hybridization. Targeting the FGF-FGFR1c pathway with anti-FGFR1c mAbs leads to drug induced valvulopathy in rats. In effect, this precluded the development of these mAbs as potential anti-obesity drugs. The valvulopathy observed was similar to that described for fenfluramine and dexafenfluramine. The pathogenesis of the drug-induced valvulopathy is considered FGFR1c-mediated, based on the specificity of the mAbs and FGFR1 mRNA expression in the heart valves.
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- 2018
30. IDOL regulates systemic energy balance through control of neuronal VLDLR expression
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Jie Gao, Stephen Lee, Jason K. Kim, Daniel Lindén, In Sook Ahn, Tracy A Cole, Andrea Ahnmark, Xia Yang, Magnus Althage, Stephanie M. Correa, Frank Seeliger, Harriet Andersén, Helen Boyd, Pernilla Eliasson, Peter Tontonoz, Ingela Maxvall, J. Edward van Veen, Alba Carreras, Anna C. Calkin, Cynthia Hong, Mohammad Bohlooly-Y, Mikael Bjursell, Peter Åkerblad, Megan G. Massa, Christina Priest, Michelle J. Porritt, Graciel Diamante, Richard T. Lee, Prashant Rajbhandari, and Douglas Arneson
- Subjects
Blood Glucose ,Knockout ,Ubiquitin-Protein Ligases ,Endocrinology, Diabetes and Metabolism ,Hypothalamus ,Adipose tissue ,Article ,Oral and gastrointestinal ,LDL ,Mice ,Mediator ,Physiology (medical) ,Receptors ,Gene expression ,Genetics ,Internal Medicine ,Animals ,2.1 Biological and endogenous factors ,Obesity ,Aetiology ,Receptor ,Liver X receptor ,Metabolic and endocrine ,Nutrition ,Mice, Knockout ,Neurons ,biology ,Liver Disease ,Neurosciences ,Cell Biology ,Diet ,Ubiquitin ligase ,Cell biology ,Receptors, LDL ,LDL receptor ,Knockout mouse ,biology.protein ,Insulin Resistance ,Energy Metabolism ,Digestive Diseases - Abstract
Liver X receptors limit cellular lipid uptake by stimulating the transcription of Inducible Degrader of the LDL Receptor (IDOL), an E3 ubiquitin ligase that targets lipoprotein receptors for degradation. The function of IDOL in systemic metabolism is incompletely understood. Here we show that loss of IDOL in mice protects against the development of diet-induced obesity and metabolic dysfunction by altering food intake and thermogenesis. Unexpectedly, analysis of tissue-specific knockout mice revealed that IDOL affects energy balance, not through its actions in peripheral metabolic tissues (liver, adipose, endothelium, intestine, skeletal muscle), but by controlling lipoprotein receptor abundance in neurons. Single-cell RNA sequencing of the hypothalamus demonstrated that IDOL deletion altered gene expression linked to control of metabolism. Finally, we identify VLDLR rather than LDLR as the primary mediator of IDOL effects on energy balance. These studies identify a role for the neuronal IDOL-VLDLR pathway in metabolic homeostasis and diet-induced obesity.
- Published
- 2019
31. Opposing Effects of Adiponectin Receptors 1 and 2 on Energy Metabolism
- Author
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Bjursell, Mikael, Ahnmark, Andrea, Bohlooly-Y, Mohammad, William-Olsson, Lena, Rhedin, Magdalena, Peng, Xiao-Rong, Ploj, Karolina, Gerdin, Anna-Karin, Arnerup, Gunnel, Elmgren, Anders, Berg, Anna-Lena, Oscarsson, Jan, and Lindén, Daniel
- Published
- 2007
32. Pnpla3 silencing with antisense oligonucleotides ameliorates nonalcoholic steatohepatitis and fibrosis in Pnpla3 I148M knock-in mice
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Daniel Lindén, Andrea Ahnmark, Piero Pingitore, Ester Ciociola, Ingela Ahlstedt, Anne-Christine Andréasson, Kavitha Sasidharan, Katja Madeyski-Bengtson, Magdalena Zurek, Rosellina M. Mancina, Anna Lindblom, Mikael Bjursell, Gerhard Böttcher, Marcus Ståhlman, Mohammad Bohlooly-Y, William G. Haynes, Björn Carlsson, Mark Graham, Richard Lee, Sue Murray, Luca Valenti, Sanjay Bhanot, Peter Åkerblad, and Stefano Romeo
- Subjects
Liver Cirrhosis ,lcsh:Internal medicine ,Membrane Proteins ,Lipase ,Oligonucleotides, Antisense ,digestive system diseases ,Mice, Inbred C57BL ,Mice ,Non-alcoholic Fatty Liver Disease ,Phospholipases A2, Calcium-Independent ,Animals ,Humans ,Female ,Gene Silencing ,lcsh:RC31-1245 - Abstract
Objective: Nonalcoholic fatty liver disease (NAFLD) is becoming a leading cause of advanced chronic liver disease. The progression of NAFLD, including nonalcoholic steatohepatitis (NASH), has a strong genetic component, and the most robust contributor is the patatin-like phospholipase domain-containing 3 (PNPLA3) rs738409 encoding the 148M protein sequence variant. We hypothesized that suppressing the expression of the PNPLA3 148M mutant protein would exert a beneficial effect on the entire spectrum of NAFLD. Methods: We examined the effects of liver-targeted GalNAc3-conjugated antisense oligonucleotide (ASO)-mediated silencing of Pnpla3 in a knock-in mouse model in which we introduced the human PNPLA3 I148M mutation. Results: ASO-mediated silencing of Pnpla3 reduced liver steatosis (p = 0.038) in homozygous Pnpla3 148M/M knock-in mutant mice but not in wild-type littermates fed a steatogenic high-sucrose diet. In mice fed a NASH-inducing diet, ASO-mediated silencing of Pnpla3 reduced liver steatosis score and NAFLD activity score independent of the Pnpla3 genotype, while reductions in liver inflammation score (p = 0.018) and fibrosis stage (p = 0.031) were observed only in the Pnpla3 knock-in 148M/M mutant mice. These responses were accompanied by reduced liver levels of Mcp1 (p = 0.026) and Timp2 (p = 0.007) specifically in the mutant knock-in mice. This may reduce levels of chemokine attracting inflammatory cells and increase the collagenolytic activity during tissue regeneration. Conclusion: This study provides the first evidence that a Pnpla3 ASO therapy can improve all features of NAFLD, including liver fibrosis, and suppress the expression of a strong innate genetic risk factor, Pnpla3 148M, which may open up a precision medicine approach in NASH. Keywords: PNPLA3, NAFLD, NASH, Fibrosis, Liver
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- 2018
33. IDOL regulates systemic energy balance through control of neuronal VLDLR expression.
- Author
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Lee, SD, Priest, C, Bjursell, M, Gao, J, Arneson, DV, Ahn, IS, Diamante, G, van Veen, JE, Massa, MG, Calkin, AC, Kim, J, Andersén, H, Rajbhandari, P, Porritt, M, Carreras, A, Ahnmark, A, Seeliger, F, Maxvall, I, Eliasson, P, Althage, M, Åkerblad, P, Lindén, D, Cole, TA, Lee, R, Boyd, H, Bohlooly-Y, M, Correa, SM, Yang, X, Tontonoz, P, Hong, C, Lee, SD, Priest, C, Bjursell, M, Gao, J, Arneson, DV, Ahn, IS, Diamante, G, van Veen, JE, Massa, MG, Calkin, AC, Kim, J, Andersén, H, Rajbhandari, P, Porritt, M, Carreras, A, Ahnmark, A, Seeliger, F, Maxvall, I, Eliasson, P, Althage, M, Åkerblad, P, Lindén, D, Cole, TA, Lee, R, Boyd, H, Bohlooly-Y, M, Correa, SM, Yang, X, Tontonoz, P, and Hong, C
- Abstract
Liver X receptors limit cellular lipid uptake by stimulating the transcription of Inducible Degrader of the LDL Receptor (IDOL), an E3 ubiquitin ligase that targets lipoprotein receptors for degradation. The function of IDOL in systemic metabolism is incompletely understood. Here we show that loss of IDOL in mice protects against the development of diet-induced obesity and metabolic dysfunction by altering food intake and thermogenesis. Unexpectedly, analysis of tissue-specific knockout mice revealed that IDOL affects energy balance, not through its actions in peripheral metabolic tissues (liver, adipose, endothelium, intestine, skeletal muscle), but by controlling lipoprotein receptor abundance in neurons. Single-cell RNA sequencing of the hypothalamus demonstrated that IDOL deletion altered gene expression linked to control of metabolism. Finally, we identify VLDLR rather than LDLR as the primary mediator of IDOL effects on energy balance. These studies identify a role for the neuronal IDOL-VLDLR pathway in metabolic homeostasis and diet-induced obesity.
- Published
- 2019
34. Input estimation for drug discovery using optimal control and Markov chain Monte Carlo approaches
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Neil D. Evans, Magnus Trägårdh, Andrea Ahnmark, Peter Gennemark, Michael J. Chappell, and Daniel Lindén
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0301 basic medicine ,Mathematical optimization ,RM ,Eflornithine ,Computer science ,Monte Carlo method ,Biological Availability ,Deconvolution ,030226 pharmacology & pharmacy ,03 medical and health sciences ,symbols.namesake ,Bayes' theorem ,Mice ,0302 clinical medicine ,Drug Discovery ,Maximum a posteriori estimation ,Animals ,Computer Simulation ,Pharmacology ,Bayes estimator ,Original Paper ,Models, Statistical ,Markov chain ,Markov Chain Monte Carlo method ,Linear system ,Markov chain Monte Carlo ,Bayes Theorem ,Optimal control ,Markov Chains ,Rats ,030104 developmental biology ,symbols ,Nonlinear dynamic systems ,Regression Analysis ,Input estimation ,Monte Carlo Method ,Algorithms ,Software - Abstract
Input estimation is employed in cases where it is desirable to recover the form of an input function which cannot be directly observed and for which there is no model for the generating process. In pharmacokinetic and pharmacodynamic modelling, input estimation in linear systems (deconvolution) is well established, while the nonlinear case is largely unexplored. In this paper, a rigorous definition of the input-estimation problem is given, and the choices involved in terms of modelling assumptions and estimation algorithms are discussed. In particular, the paper covers Maximum a Posteriori estimates using techniques from optimal control theory, and full Bayesian estimation using Markov Chain Monte Carlo (MCMC) approaches. These techniques are implemented using the optimisation software CasADi, and applied to two example problems: one where the oral absorption rate and bioavailability of the drug eflornithine are estimated using pharmacokinetic data from rats, and one where energy intake is estimated from body-mass measurements of mice exposed to monoclonal antibodies targeting the fibroblast growth factor receptor (FGFR) 1c. The results from the analysis are used to highlight the strengths and weaknesses of the methods used when applied to sparsely sampled data. The presented methods for optimal control are fast and robust, and can be recommended for use in drug discovery. The MCMC-based methods can have long running times and require more expertise from the user. The rigorous definition together with the illustrative examples and suggestions for software serve as a highly promising starting point for application of input-estimation methods to problems in drug discovery. Electronic supplementary material The online version of this article (doi:10.1007/s10928-016-9467-z) contains supplementary material, which is available to authorized users.
- Published
- 2016
35. Secretagogin is increased in plasma from type 2 diabetes patients and potentially reflects stress and islet dysfunction
- Author
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Maria Sörhede Winzell, Daniel Karlsson, Helen Jongsma Wallin, Anders Ericsson-Dahlstrand, Maria J. Pereira, Stanko Skrtic, Paulina Vachet, Sara F. Hansson, Jan W. Eriksson, Andrea Ahnmark, Maria Chiara Magnone, Pia Davidsson, and Alex-Xianghua Zhou
- Subjects
Male ,Cytoplasm ,endocrine system diseases ,medicine.medical_treatment ,Cell- och molekylärbiologi ,Cell ,Islets of Langerhans Transplantation ,Biochemistry ,Mice ,0302 clinical medicine ,Endocrinology ,Medicine ,Insulin ,Small interfering RNAs ,lcsh:Science ,education.field_of_study ,Innate Immune System ,geography.geographical_feature_category ,Organic Compounds ,Type 2 Diabetes ,Nucleic acids ,Blood ,Physical Sciences ,Cytokines ,medicine.medical_specialty ,endocrine system ,Endocrine Disorders ,Immunology ,Carbohydrates ,03 medical and health sciences ,Islets of Langerhans ,Diabetes Mellitus ,Genetics ,Humans ,Secretion ,education ,Non-coding RNA ,Aged ,lcsh:R ,Chemical Compounds ,Biology and Life Sciences ,Glucose Tolerance Test ,Molecular Development ,medicine.disease ,Glucagon ,Hormones ,030104 developmental biology ,Glucose ,Diabetes Mellitus, Type 2 ,lcsh:Q ,Gene expression ,030217 neurology & neurosurgery ,Biomarkers ,Cell and Molecular Biology ,Developmental Biology ,0301 basic medicine ,Physiology ,lcsh:Medicine ,Type 2 diabetes ,Endoplasmic Reticulum ,Cohort Studies ,Insulin-Secreting Cells ,Immune Physiology ,Medicine and Health Sciences ,Cellular Stress Responses ,Multidisciplinary ,Monosaccharides ,Middle Aged ,Islet ,Body Fluids ,Chemistry ,medicine.anatomical_structure ,Cell Processes ,Biomarker (medicine) ,Female ,Anatomy ,SECRETAGOGIN ,Research Article ,Adult ,Enzyme-Linked Immunosorbent Assay ,Blood Plasma ,Diabetes Mellitus, Experimental ,Internal medicine ,Animals ,Cell Nucleus ,Diabetic Endocrinology ,geography ,business.industry ,Pancreatic islets ,Organic Chemistry ,Cell Biology ,Gene regulation ,Metabolic Disorders ,Immune System ,RNA ,business ,Secretagogins - Abstract
Beta cell dysfunction accompanies and drives the progression of type 2 diabetes mellitus (T2D), but there are few clinical biomarkers available to assess islet cell stress in humans. Secretagogin, a protein enriched in pancreatic islets, demonstrates protective effects on beta cell function in animals. However, its potential as a circulating biomarker released from human beta cells and islets has not been studied. In this study primary human islets, beta cells and plasma samples were used to explore secretion and expression of secretagogin in relation to the T2D pathology. Secretagogin was abundantly and specifically expressed and secreted from human islets. Furthermore, T2D patients had an elevated plasma level of secretagogin compared with matched healthy controls, which was confirmed in plasma of diabetic mice transplanted with human islets. Additionally, the plasma secretagogin level of the human cohort had an inverse correlation to clinical assessments of beta cell function. To explore the mechanism of secretagogin release in vitro, human beta cells (EndoC-[beta H1) were exposed to elevated glucose or cellular stress-inducing agents. Secretagogin was not released in parallel with glucose stimulated insulin release, but was markedly elevated in response to endoplasmic reticulum stressors and cytokines. These findings indicate that secretagogin is a potential novel biomarker, reflecting stress and islet cell dysfunction in T2D patients.
- Published
- 2018
36. Secretagogin is increased in plasma from type 2 diabetes patients and potentially reflects stress and islet dysfunction
- Author
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Hansson, Sara F., Zhou, Alex-Xianghua, Vachet, Pauline, Eriksson, Jan W, Pereira, Maria J., Skrtic, Stanko, Wallin, Helen Jongsma, Ericsson-Dahlstrand, Anders, Karlsson, Daniel, Ahnmark, Andrea, Winzell, Maria Sorhede, Magnone, Maria Chiara, Davidsson, Pia, Hansson, Sara F., Zhou, Alex-Xianghua, Vachet, Pauline, Eriksson, Jan W, Pereira, Maria J., Skrtic, Stanko, Wallin, Helen Jongsma, Ericsson-Dahlstrand, Anders, Karlsson, Daniel, Ahnmark, Andrea, Winzell, Maria Sorhede, Magnone, Maria Chiara, and Davidsson, Pia
- Abstract
Beta cell dysfunction accompanies and drives the progression of type 2 diabetes mellitus (T2D), but there are few clinical biomarkers available to assess islet cell stress in humans. Secretagogin, a protein enriched in pancreatic islets, demonstrates protective effects on beta cell function in animals. However, its potential as a circulating biomarker released from human beta cells and islets has not been studied. In this study primary human islets, beta cells and plasma samples were used to explore secretion and expression of secretagogin in relation to the T2D pathology. Secretagogin was abundantly and specifically expressed and secreted from human islets. Furthermore, T2D patients had an elevated plasma level of secretagogin compared with matched healthy controls, which was confirmed in plasma of diabetic mice transplanted with human islets. Additionally, the plasma secretagogin level of the human cohort had an inverse correlation to clinical assessments of beta cell function. To explore the mechanism of secretagogin release in vitro, human beta cells (EndoC-[beta H1) were exposed to elevated glucose or cellular stress-inducing agents. Secretagogin was not released in parallel with glucose stimulated insulin release, but was markedly elevated in response to endoplasmic reticulum stressors and cytokines. These findings indicate that secretagogin is a potential novel biomarker, reflecting stress and islet cell dysfunction in T2D patients.
- Published
- 2018
- Full Text
- View/download PDF
37. The acute glucose lowering effect of specific GPR120 activation in mice is mainly driven by glucagon-like peptide 1
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Lisbeth Kristensson, Maria Sörhede Winzell, Sam D. Groombridge, Piotr Raubo, Andrea Ahnmark, William McCoull, Monika Sundqvist, Susanna Myhre, Polla Magnus, Ann-Christin Nyström, Linda Sundström, and Mats Någård
- Subjects
Blood Glucose ,0301 basic medicine ,Physiology ,Oral Glucose Suppression Test ,medicine.medical_treatment ,lcsh:Medicine ,Pharmacology ,Biochemistry ,Receptors, G-Protein-Coupled ,Mice ,Endocrinology ,Glucose Metabolism ,Drug Metabolism ,Glucagon-Like Peptide 1 ,Insulin Secretion ,Cyclic AMP ,Medicine and Health Sciences ,Insulin ,lcsh:Science ,beta-Arrestins ,Glucose tolerance test ,Multidisciplinary ,medicine.diagnostic_test ,Organic Compounds ,Chemistry ,Monosaccharides ,Receptor antagonist ,Physical Sciences ,Carbohydrate Metabolism ,Female ,Signal Transduction ,Research Article ,Agonist ,Cell Physiology ,Gs alpha subunit ,medicine.drug_class ,Carbohydrates ,CHO Cells ,Carbohydrate metabolism ,Cell Line ,Islets of Langerhans ,03 medical and health sciences ,Cricetulus ,GTP-Binding Proteins ,In vivo ,medicine ,Animals ,Humans ,Pharmacokinetics ,Secretion ,Diabetic Endocrinology ,Endocrine Physiology ,Beta-Arrestins ,Organic Chemistry ,lcsh:R ,Chemical Compounds ,Biology and Life Sciences ,Cell Biology ,Glucose Tolerance Test ,Hormones ,Cell Metabolism ,Pharmacologic-Based Diagnostics ,Mice, Inbred C57BL ,Metabolism ,Glucose ,030104 developmental biology ,lcsh:Q ,Physiological Processes - Abstract
The mechanism behind the glucose lowering effect occurring after specific activation of GPR120 is not completely understood. In this study, a potent and selective GPR120 agonist was developed and its pharmacological properties were compared with the previously described GPR120 agonist Metabolex-36. Effects of both compounds on signaling pathways and GLP-1 secretion were investigated in vitro. The acute glucose lowering effect was studied in lean wild-type and GPR120 null mice following oral or intravenous glucose tolerance tests. In vitro, in GPR120 overexpressing cells, both agonists signaled through Gαq, Gαs and the β-arrestin pathway. However, in mouse islets the signaling pathway was different since the agonists reduced cAMP production. The GPR120 agonists stimulated GLP-1 secretion both in vitro in STC-1 cells and in vivo following oral administration. In vivo GPR120 activation induced significant glucose lowering and increased insulin secretion after intravenous glucose administration in lean mice, while the agonists had no effect in GPR120 null mice. Exendin 9–39, a GLP-1 receptor antagonist, abolished the GPR120 induced effects on glucose and insulin following an intravenous glucose challenge. In conclusion, GLP-1 secretion is an important mechanism behind the acute glucose lowering effect following specific GPR120 activation.
- Published
- 2017
38. Monoclonal antibody targeting of fibroblast growth factor receptor 1c causes cardiac valvulopathy in rats
- Author
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Buss, Nicholas, primary, Lapointe, Jean-Martin, additional, de Haan, Lolke, additional, Price, Sally, additional, Ahnmark, Andrea, additional, Irving, Lorraine, additional, Buchanan, Andrew, additional, Keyes, Feenagh, additional, Davidsson, Pia, additional, Dixit, Rakesh, additional, and Lindén, Daniel, additional
- Published
- 2018
- Full Text
- View/download PDF
39. Secretagogin is increased in plasma from type 2 diabetes patients and potentially reflects stress and islet dysfunction
- Author
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Hansson, Sara F., primary, Zhou, Alex-Xianghua, additional, Vachet, Paulina, additional, Eriksson, Jan W., additional, Pereira, Maria J., additional, Skrtic, Stanko, additional, Jongsma Wallin, Helen, additional, Ericsson-Dahlstrand, Anders, additional, Karlsson, Daniel, additional, Ahnmark, Andrea, additional, Sörhede Winzell, Maria, additional, Magnone, Maria Chiara, additional, and Davidsson, Pia, additional
- Published
- 2018
- Full Text
- View/download PDF
40. The acute glucose lowering effect of specific GPR120 activation in mice is mainly driven by glucagon-like peptide 1
- Author
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Sundström, Linda, primary, Myhre, Susanna, additional, Sundqvist, Monika, additional, Ahnmark, Andrea, additional, McCoull, William, additional, Raubo, Piotr, additional, Groombridge, Sam D., additional, Polla, Magnus, additional, Nyström, Ann-Christin, additional, Kristensson, Lisbeth, additional, Någård, Mats, additional, and Winzell, Maria Sörhede, additional
- Published
- 2017
- Full Text
- View/download PDF
41. Hyperglycemia Induced by Glucokinase Deficiency Accelerates Atherosclerosis Development and Impairs Lesion Regression in Combined Heterozygous Glucokinase and the Apolipoprotein E-Knockout Mice
- Author
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Ann-Cathrine Jönsson-Rylander, Andrea Ahnmark, Margareta Behrendt, Damilola D. Adingupu, Anne-Christine Andréasson, Brendan Leighton, Mikael Brusberg, and Suvi E. Heinonen
- Subjects
Male ,0301 basic medicine ,Apolipoprotein E ,medicine.medical_specialty ,Article Subject ,Endocrinology, Diabetes and Metabolism ,030204 cardiovascular system & hematology ,Biology ,Carbohydrate metabolism ,Diet, High-Fat ,lcsh:Diseases of the endocrine glands. Clinical endocrinology ,Lesion ,Mice ,03 medical and health sciences ,Apolipoproteins E ,0302 clinical medicine ,Endocrinology ,TheoryofComputation_ANALYSISOFALGORITHMSANDPROBLEMCOMPLEXITY ,Diabetes mellitus ,Internal medicine ,Glucokinase ,medicine ,Animals ,Aorta ,Mice, Knockout ,lcsh:RC648-665 ,Myocardium ,Atherosclerosis ,medicine.disease ,Lipids ,Phenotype ,030104 developmental biology ,Hyperglycemia ,Knockout mouse ,Disease Progression ,Female ,lipids (amino acids, peptides, and proteins) ,Lipid lowering ,medicine.symptom ,Research Article - Abstract
Aim. Models combining diabetes and atherosclerosis are important in evaluating the cardiovascular (CV) effects and safety of antidiabetes drugs in the development of treatments targeting CV complications. Our aim was to evaluate if crossing the heterozygous glucokinase knockout mouse (GK+/−) and hyperlipidemic mouse deficient in apolipoprotein E (ApoE−/−) will generate a disease model exhibiting a diabetic and macrovascular phenotype.Methods. The effects of defective glucokinase on the glucose metabolism and on the progression and regression of atherosclerosis on high-fat diets were studied in both genders of GK+/−ApoE−/−and ApoE−/−mice. Coronary vascular function of the female GK+/−ApoE−/−and ApoE−/−mice was also investigated.Results. GK+/−ApoE−/−mice show a stable hyperglycemia which was increased on Western diet. In oral glucose tolerance test, GK+/−ApoE−/−mice showed significant glucose intolerance and impaired glucose-stimulated insulin secretion. Plasma lipids were comparable with ApoE−/−mice; nevertheless the GK+/−ApoE−/−mice showed slightly increased atherosclerosis development.Conclusions. The GK+/−ApoE−/−mice showed a stable and reproducible hyperglycemia, accelerated atherosclerotic lesion progression, and no lesion regression after lipid lowering. This novel model provides a promising tool for drug discovery, enabling the evaluation of compound effects against both diabetic and cardiovascular endpoints simultaneously in one animal model.
- Published
- 2016
42. The role of mitochondrial glycerol-3-phosphate acyltransferase-1 in regulating lipid and glucose homeostasis in high-fat diet fed mice
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Marianne Wedin, Anders Elmgren, Andrea Ahnmark, Mohammad Bohlooly-Y, Nigel Turner, Misak Yazdi, Michael Snaith, Anna-Karin Asztély, Daniel Lindén, Fredrik Osla, Lena William-Olsson, and Sandra A. Schreyer
- Subjects
Male ,medicine.medical_specialty ,Biophysics ,Carbohydrate metabolism ,Biology ,Weight Gain ,Biochemistry ,Mice ,Internal medicine ,Glucose Intolerance ,medicine ,Animals ,Homeostasis ,Glucose homeostasis ,Obesity ,Molecular Biology ,Beta oxidation ,Respiratory exchange ratio ,Triglycerides ,Cell Biology ,medicine.disease ,Dietary Fats ,Mice, Mutant Strains ,Diet ,Mitochondria ,Fatty Liver ,Disease Models, Animal ,Cholesterol ,Glucose ,Endocrinology ,Acyltransferase ,Glycerol-3-Phosphate O-Acyltransferase ,Ketone bodies ,Female ,Steatosis ,Energy Metabolism - Abstract
Glycerol-3-phosphate acyltransferase (GPAT) is involved in triacylglycerol (TAG) and phospholipid synthesis, catalyzing the first committed step. In order to further investigate the in vivo importance of the dominating mitochondrial variant, GPAT1, a novel GPAT1(-/-) mouse model was generated and studied. Female GPAT1(-/-) mice had reduced body weight-gain and adiposity when fed chow diet compared with littermate wild-type controls. Furthermore, GPAT1(-/-) females on chow diet showed decreased liver TAG content, plasma cholesterol and TAG levels and increased ex vivo liver fatty acid oxidation and plasma ketone bodies. However, these beneficial effects were abolished and the glucose tolerance tended to be impaired when GPAT1(-/-) females were fed a long-term high-fat diet (HFD). GPAT1-deficiency was not associated with altered whole body energy expenditure or respiratory exchange ratio. In addition, there were no changes in male GPAT1(-/-) mice fed either diet except for increased plasma ketone bodies on chow diet, indicating a gender-specific phenotype. Thus, GPAT1-deficiency does not protect against HFD-induced obesity, hepatic steatosis or whole body glucose intolerance.
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- 2008
43. Opposing Effects of Adiponectin Receptors 1 and 2 on Energy Metabolism
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Jan Oscarsson, Karolina Ploj, Gunnel Arnerup, Mohammad Bohlooly-Y, Magdalena Rhedin, Anna-Karin Gerdin, Andrea Ahnmark, Lena William-Olsson, Daniel Lindén, Xiao-Rong Peng, Mikael Bjursell, Anna-Lena Berg, and Anders Elmgren
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Male ,medicine.medical_specialty ,Time Factors ,ADIPOR2 Gene ,Endocrinology, Diabetes and Metabolism ,Adipokine ,Receptors, Cell Surface ,AMP-Activated Protein Kinases ,Motor Activity ,Protein Serine-Threonine Kinases ,Biology ,Mice ,Multienzyme Complexes ,Internal medicine ,Testis ,Internal Medicine ,medicine ,Animals ,PPAR alpha ,Receptor ,Adiposity ,Mice, Knockout ,Adiponectin ,Body Weight ,Brain ,Lipid metabolism ,Feeding Behavior ,Glucose ,Endocrinology ,Adipose Tissue ,Knockout mouse ,Decreased glucose tolerance ,Female ,Receptors, Adiponectin ,Energy Metabolism ,Signal Transduction ,Hormone - Abstract
The adipocyte-derived hormone adiponectin regulates glucose and lipid metabolism and influences the risk for developing obesity, type 2 diabetes, and cardiovascular disease. Adiponectin binds to two different seven-transmembrane domain receptors termed AdipoR1 and AdipoR2. To study the physiological importance of these receptors, AdipoR1 gene knockout mice ( AdipoR1 −/− ) and AdipoR2 gene knockout mice ( AdipoR2 −/− ) were generated. AdipoR1 −/− mice showed increased adiposity associated with decreased glucose tolerance, spontaneous locomotor activity, and energy expenditure. However, AdipoR2 −/− mice were lean and resistant to high-fat diet–induced obesity associated with improved glucose tolerance and higher spontaneous locomotor activity and energy expenditure and reduced plasma cholesterol levels. Thus, AdipoR1 and AdipoR2 are clearly involved in energy metabolism but have opposing effects.
- Published
- 2007
44. Studies of nontarget-mediated distribution of human full-length IgG1 antibody and its FAb fragment in cardiovascular and metabolic-related tissues
- Author
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Ann-Sofi Söderling, Christine Flodin, Peter Gennemark, Lena Svensson, Ewa Wanag, Pia Davidsson, Andrea Ahnmark, and Valentina Screpanti-Sundqvist
- Subjects
Pharmaceutical Science ,Immunoglobulin Fab Fragments ,Mice ,Pharmacokinetics ,Antigen ,medicine ,Distribution (pharmacology) ,Animals ,Humans ,Tissue Distribution ,Kidney ,biology ,medicine.diagnostic_test ,Chemistry ,Myocardium ,Area under the curve ,Antibodies, Monoclonal ,Heart ,Molecular biology ,Mice, Inbred C57BL ,medicine.anatomical_structure ,Immunoassay ,Immunoglobulin G ,biology.protein ,Female ,Antibody ,Perfusion - Abstract
Tissue distribution and pharmacokinetics (PK) of full-length nontargeted antibody and its antigen-binding fragment (FAb) were evaluated for a range of tissues primarily of interest for cardiovascular and metabolic diseases. Mice were intravenously injected with a dose of 10 mg/kg of either human IgGlor its FAb fragment; perfused tissues were collected at a range of time points over 3 weeks for the human IgG1 antibody and 1 week for the human FAb antibody. Tissues were homogenized and antibody concentrations were measured by specific immunoassays on the Gyros system. Exposure in terms of maximum concentration ( C max ) and area under the curve was assessed for all nine tissues. Tissue exposure of full-length antibody relative to plasma exposure was found to be between 1% and 10%, except for brain (0.2%). Relative concentrations of FAb antibody were the same, except for kidney tissue, where the antibody concentration was found to be ten times higher than in plasma. However, the absolute tissue uptake of full-length IgG was significantly higher than the absolute tissue uptake of the FAb antibody. This study provides a reference PK state for full-length whole and FAb antibodies in tissues related to cardiovascular and metabolic diseases that do not include antigen or antibody binding.
- Published
- 2014
45. Hyperglycemia Induced by Glucokinase Deficiency Accelerates Atherosclerosis Development and Impairs Lesion Regression in Combined Heterozygous Glucokinase and the Apolipoprotein E-Knockout Mice
- Author
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Adingupu, Damilola D., primary, Heinonen, Suvi E., additional, Andréasson, Anne-Christine, additional, Brusberg, Mikael, additional, Ahnmark, Andrea, additional, Behrendt, Margareta, additional, Leighton, Brendan, additional, and Jönsson-Rylander, Ann-Cathrine, additional
- Published
- 2016
- Full Text
- View/download PDF
46. When the patient does not go by ambulance for further care, a study with aspect of patient safety : A retrospective study of 137 ambulance dispatches
- Author
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Insulander Ahnmark, Kajsa and Wennberg, Jonny
- Subjects
Patient safety ,Journal ,Ambulans ,Patient ,TRansport ,Ambulanssjuksköterska ,Nurse ,Specialist nurse in prehospital care science ,Patientsäkerhet ,Ambulance ,Sjuksköterska - Abstract
Introduction: During the past 40 years the ambulance service in Sweden has evolved from mainly being a source of transport to today’s high-tech caring facilities that enable qualified care to start already in the patient’s home. This first level of care is now provided by registered nurses and registered nurses with specialist training in pre hospital care. At the same time as the care provided is becoming more advanced, results from studies demonstrate that the amount of dispatches to patients that lack the need for ambulance care and transport is increasing. Nurses in pre-hospital care possess the knowledge, training and authority to perform an initial assessment of patients and also treat patients according to local and national guidelines. After the treatment it would sometimes be possible for the patients to remain at home without having to use ambulance transport to an emergency department or in other cases find other means of transport to hospital. Today this is, in Sweden, an accepted standard for by district nurses who are mandated to refer, even after only telephone consulting, the patients to self-care. Ambulance nurses lack this according to present guidelines. If a patient is to remain on-scene or home, a strict protocol of documentation has to be filled-in as well as the ambulance crew being in contact with a doctor. In this study, the authors visualize what patient categories stay on-scene or home, what types of examinations was performed and if the patient safety is ensured. Objective: The aim of this study was to visualize patient safety when the patient is not transported to hospital by ambulance. Method: A quantitative, descriptive and retrospective design and analysis of 137 ambulance medical records where the patient was left at home after the initial assessment. Results: The results demonstrate that the patients who wish to remain on-scene have various different conditions. The majority stayed home at their own request and without any further treatment being performed by the pre hospital care provider. In 28 per cent the patients received some kind of treatment, and in some of the cases patients refused ambulance transport even when the ambulance nurse strongly recommended this. This study also demonstrated that, in many cases, the patients´ history as well as the patients´ status were incomplete documented. The ambulance nurse performed, in median, four different examinations on the patients. In more than half of the cases the nurses had documented that the patient had some kind of attendance. Counseling was given both to patients and sometimes to the patients’ family member. A lack of sufficient documentation in the patients’ medical record was found and also that consultation of a doctor only has been completed in 15 per cent. Of a total of 137 patients there were three patients who called for an ambulance within the following 24 hours. One of these became aggressive during the first time of visit, and therefore the nurse wasn´t able to examine her thoroughly. The two other patients do not differ regarding the extent of the examination compared to those who didn´t call for ambulance again. Conclusion: Although this paper demonstrates that patients´ safety has not been compromised in the examined records, the authors recommend further studies on patient safety when patient remain on-scene. There is also a need for more specific and valid indicators. Documentation and adherence to guidelines were, however, in this study found to be insufficient. Key words: patient safety, ambulance, patient, specialist nurse in pre hospital care science, nurse, transport, journal.
- Published
- 2012
47. Liver-directed overexpression of mitochondrial glycerol-3-phosphate acyltransferase results in hepatic steatosis, increased triacylglycerol secretion and reduced fatty acid oxidation
- Author
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Lennart Svensson, John C. Clapham, Carina Hallberg, Helena Peilot Sjögren, Bruno Becker, Kim Ekroos, Jan Oscarsson, Sandra A. Schreyer, Andrea Ahnmark, Lena William-Olsson, and Daniel Lindén
- Subjects
Male ,medicine.medical_specialty ,Recombinant Fusion Proteins ,Phospholipid ,Carbohydrates ,Mitochondria, Liver ,Mitochondrion ,Biochemistry ,Mass Spectrometry ,Diglycerides ,chemistry.chemical_compound ,Mice ,Internal medicine ,Adipocyte ,Genetics ,medicine ,Animals ,Obesity ,RNA, Messenger ,Molecular Biology ,Beta oxidation ,Phospholipids ,Triglycerides ,Diacylglycerol kinase ,Fatty liver ,Fatty Acids ,medicine.disease ,Lipids ,Fatty Liver ,Malonyl Coenzyme A ,Mice, Inbred C57BL ,Endocrinology ,chemistry ,Amino Acid Substitution ,Acyltransferase ,Enzyme Induction ,Glycerol-3-Phosphate O-Acyltransferase ,Steatosis ,Insulin Resistance ,Oxidation-Reduction ,Biotechnology - Abstract
Glycerol-3-phosphate acyltransferase (GPAT) catalyzes the first committed step in triacylglycerol (TAG) and phospholipid biosynthesis. GPAT activity has been identified in both ER and mitochondrial subcellular fractions. The ER activity dominates in most tissues except in liver, where the mitochondrial isoform (mtGPAT) can constitute up to 50% of the total activity. To study the in vivo effects of hepatic mtGPAT overexpression, mice were transduced with adenoviruses expressing either murine mtGPAT or a catalytically inactive variant of the enzyme. Overexpressing mtGPAT resulted in massive 12- and 7-fold accumulation of liver TAG and diacylglycerol, respectively but had no effect on phospholipid or cholesterol ester content. Histological analysis showed extensive lipid accumulation in hepatocytes. Furthermore, mtGPAT transduction markedly increased adipocyte differentiation-related protein and stearoyl-CoA desaturase-1 (SCD-1) in the liver. In line with increased SCD-1 expression, 18:1 and 16:1 in the hepatic TAG fraction increased. In addition, mtGPAT overexpression decreased ex vivo fatty acid oxidation, increased liver TAG secretion rate 2-fold, and increased plasma TAG and cholesterol levels. These results support the hypothesis that increased hepatic mtGPAT activity associated with obesity and insulin resistance contributes to increased TAG biosynthesis and inhibition of fatty acid oxidation, responses that would promote hepatic steatosis and dyslipidemia.
- Published
- 2006
48. PPARalpha activation increases triglyceride mass and adipose differentiation-related protein in hepatocytes
- Author
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Anna Ljungberg, Helena Peilot-Sjögren, Andrea Ahnmark, Lena William-Olsson, Ulrika Edvardsson, Jan Oscarsson, and Daniel Lindén
- Subjects
Apolipoprotein B ,triglyceride secretion ,Palmitic Acid ,Adipose tissue ,Gene Expression ,Biochemistry ,Palmitic acid ,chemistry.chemical_compound ,Mice ,Endocrinology ,Receptor ,Beta oxidation ,fatty acid oxidation ,Mice, Knockout ,biology ,Acyl-CoA Dehydrogenase, Long-Chain ,Peroxisome ,Wy14,643 ,Liver ,Apolipoprotein B-100 ,Peroxisome Proliferators ,Oxidation-Reduction ,congenital, hereditary, and neonatal diseases and abnormalities ,medicine.medical_specialty ,QD415-436 ,triglyceride synthesis ,Transfection ,Perilipin-2 ,Internal medicine ,medicine ,Animals ,Secretion ,PPAR alpha ,primary hepatocytes ,Triglycerides ,Apolipoproteins B ,Triglyceride ,Carnitine O-Palmitoyltransferase ,Membrane Proteins ,Cell Biology ,Dietary Fats ,eye diseases ,Mice, Inbred C57BL ,Pyrimidines ,chemistry ,biology.protein ,Hepatocytes ,Acyl-CoA Oxidase ,Apolipoprotein B-48 - Abstract
Adipose differentiation-related protein (ADRP) is a lipid droplet-associated protein that is expressed in various tissues. In mice treated with the peroxisome proliferator-activated receptor alpha (PPARalpha) agonist Wy14,643 (Wy), hepatic mRNA and protein levels of ADRP as well as hepatic triglyceride content increased. Also in primary mouse hepatocytes, Wy increased ADRP expression and intracellular triglyceride mass. The triglyceride mass increased in spite of unchanged triglyceride biosynthesis and increased palmitic acid oxidation. However, Wy incubation decreased the secretion of newly synthesized triglycerides, whereas apolipoprotein B secretion increased. Thus, decreased availability of triglycerides for VLDL assembly could help to explain the cellular accumulation of triglycerides after Wy treatment. We hypothesized that this effect could be mediated by increased ADRP expression. Similar to PPARalpha activation, adenovirus-mediated ADRP overexpression in mouse hepatocytes enhanced cellular triglyceride mass and decreased the secretion of newly synthesized triglycerides. In ADRP-overexpressing cells, Wy incubation resulted in a further decrease in triglyceride secretion. This effect of Wy was not attributable to decreased cellular triglycerides after increased fatty acid oxidation because the triglyceride mass in Wy-treated ADRP-overexpressing cells was unchanged. In summary, PPARalpha activation prevents the availability of triglycerides for VLDL assembly and increases hepatic triglyceride content in part by increasing the expression of ADRP.
- Published
- 2005
49. Monoclonal Antibody Targeting of Fibroblast Growth Factor Receptor 1c Ameliorates Obesity and Glucose Intolerance via Central Mechanisms
- Author
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Lelliott, Christopher J., primary, Ahnmark, Andrea, additional, Admyre, Therese, additional, Ahlstedt, Ingela, additional, Irving, Lorraine, additional, Keyes, Feenagh, additional, Patterson, Laurel, additional, Mumphrey, Michael B., additional, Bjursell, Mikael, additional, Gorman, Tracy, additional, Bohlooly-Y, Mohammad, additional, Buchanan, Andrew, additional, Harrison, Paula, additional, Vaughan, Tristan, additional, Berthoud, Hans-Rudolf, additional, and Lindén, Daniel, additional
- Published
- 2014
- Full Text
- View/download PDF
50. Monoclonal Antibody Targeting of Fibroblast Growth Factor Receptor 1c Ameliorates Obesity and Glucose Intolerance via Central Mechanisms
- Author
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Andrea Ahnmark, Andrew Buchanan, Mohammad Bohlooly-Y, Ingela Ahlstedt, Daniel Lindén, Laurel M. Patterson, Feenagh Keyes, Lorraine Irving, Tracy Gorman, Mikael Bjursell, Christopher J. Lelliott, Hans-Rudolf Berthoud, Therese Admyre, Michael B. Mumphrey, Tristan J. Vaughan, Paula Harrison, Lelliott, Christopher [0000-0001-8087-4530], and Apollo - University of Cambridge Repository
- Subjects
Leptin ,Serum Response Factor ,Physiology ,lcsh:Medicine ,Mice, Obese ,Biochemistry ,Eating ,Mice ,Endocrinology ,0302 clinical medicine ,Immune Physiology ,Drug Discovery ,Medicine and Health Sciences ,Insulin ,Receptors, Somatostatin ,Chemokine CCL7 ,lcsh:Science ,Receptor ,Chemokine CCL2 ,Mice, Knockout ,2. Zero hunger ,0303 health sciences ,Multidisciplinary ,digestive, oral, and skin physiology ,Antibodies, Monoclonal ,Ribosomal Protein S6 Kinases, 70-kDa ,3. Good health ,Melanocortin 4 receptor ,Physiological Parameters ,Hormone receptor ,Hypothalamus ,Circumventricular Organs ,Cytokines ,Receptor, Melanocortin, Type 4 ,Female ,Mitogen-Activated Protein Kinases ,Signal transduction ,Melanocortin ,hormones, hormone substitutes, and hormone antagonists ,Research Article ,Signal Transduction ,medicine.medical_specialty ,Drug Research and Development ,Biology ,03 medical and health sciences ,Internal medicine ,Glucose Intolerance ,medicine ,Animals ,Humans ,Obesity ,Receptor, Fibroblast Growth Factor, Type 1 ,030304 developmental biology ,Diabetic Endocrinology ,Pharmacology ,Endocrine Physiology ,lcsh:R ,Body Weight ,Arcuate Nucleus of Hypothalamus ,Biology and Life Sciences ,Molecular Development ,Hormones ,Orexin ,Pharmacodynamics ,Gene Expression Regulation ,lcsh:Q ,Insulin Resistance ,Energy Metabolism ,030217 neurology & neurosurgery ,Developmental Biology - Abstract
We have generated a novel monoclonal antibody targeting human FGFR1c (R1c mAb) that caused profound body weight and body fat loss in diet-induced obese mice due to decreased food intake (with energy expenditure unaltered), in turn improving glucose control. R1c mAb also caused weight loss in leptin-deficient ob/ob mice, leptin receptor-mutant db/db mice, and in mice lacking either the melanocortin 4 receptor or the melanin-concentrating hormone receptor 1. In addition, R1c mAb did not change hypothalamic mRNA expression levels of Agrp, Cart, Pomc, Npy, Crh, Mch, or Orexin, suggesting that R1c mAb could cause food intake inhibition and body weight loss via other mechanisms in the brain. Interestingly, peripherally administered R1c mAb accumulated in the median eminence, adjacent arcuate nucleus and in the circumventricular organs where it activated the early response gene c-Fos. As a plausible mechanism and coinciding with the initiation of food intake suppression, R1c mAb induced hypothalamic expression levels of the cytokines Monocyte chemoattractant protein 1 and 3 and ERK1/2 and p70 S6 kinase 1 activation.
- Published
- 2014
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