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Zhou P, Li L, Lin Z, Ming X, Feng Y, Hu Y, Chen X. Exploring the Shared Genetic Architecture Between Obstructive Sleep Apnea and Body Mass Index. Nat Sci Sleep 2024; 16:711-723. [PMID: 38863482 PMCID: PMC11166156 DOI: 10.2147/nss.s459136] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/19/2024] [Accepted: 05/25/2024] [Indexed: 06/13/2024] Open
Abstract
Purpose The reciprocal comorbidity of obstructive sleep apnea (OSA) and body mass index (BMI) has been observed, yet the shared genetic architecture between them remains unclear. This study aimed to explore the genetic overlaps between them. Methods Summary statistics were acquired from the genome-wide association studies (GWASs) on OSA (Ncase = 41,704; Ncontrol = 335,573) and BMI (Noverall = 461,460). A comprehensive genome-wide cross-trait analysis was performed to quantify global and local genetic correlation, infer the bidirectional causal relationships, detect independent pleiotropic loci, and investigate potential comorbid genes. Results A positive significant global genetic correlation between OSA and BMI was observed (r g = 0.52, P = 2.85e-122), which was supported by three local signal. The Mendelian randomization analysis confirmed bidirectional causal associations. In the meta-analysis of cross-traits GWAS, a total of 151 single-nucleotide polymorphisms were found to be pleiotropic between OSA and BMI. Additionally, we discovered that the genetic association between OSA and BMI is concentrated in 12 brain regions. Finally, a total 134 expression-tissue pairs were observed to have a significant impact on both OSA and BMI within the specified brain regions. Conclusion Our comprehensive genome-wide cross-trait analysis indicates a shared genetic architecture between OSA and BMI, offering new perspectives on the possible mechanisms involved.
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Affiliation(s)
- Peng Zhou
- Department of Otorhinolaryngology, Head and Neck Surgery, Zhongnan Hospital of Wuhan University, Wuhan, Hubei, People’s Republic of China
- Sleep Medicine Centre, Zhongnan Hospital of Wuhan University, Wuhan, Hubei, People’s Republic of China
| | - Ling Li
- Department of Nuclear Medicine, Zhongnan Hospital of Wuhan University, Wuhan, Hubei, People’s Republic of China
| | - Zehua Lin
- Department of Otorhinolaryngology, Head and Neck Surgery, Zhongnan Hospital of Wuhan University, Wuhan, Hubei, People’s Republic of China
- Sleep Medicine Centre, Zhongnan Hospital of Wuhan University, Wuhan, Hubei, People’s Republic of China
| | - Xiaoping Ming
- Department of Otorhinolaryngology, Head and Neck Surgery, Zhongnan Hospital of Wuhan University, Wuhan, Hubei, People’s Republic of China
- Sleep Medicine Centre, Zhongnan Hospital of Wuhan University, Wuhan, Hubei, People’s Republic of China
| | - Yiwei Feng
- Department of Otorhinolaryngology, Head and Neck Surgery, Zhongnan Hospital of Wuhan University, Wuhan, Hubei, People’s Republic of China
- Sleep Medicine Centre, Zhongnan Hospital of Wuhan University, Wuhan, Hubei, People’s Republic of China
| | - Yifan Hu
- Department of Otorhinolaryngology, Head and Neck Surgery, Zhongnan Hospital of Wuhan University, Wuhan, Hubei, People’s Republic of China
- Sleep Medicine Centre, Zhongnan Hospital of Wuhan University, Wuhan, Hubei, People’s Republic of China
| | - Xiong Chen
- Department of Otorhinolaryngology, Head and Neck Surgery, Zhongnan Hospital of Wuhan University, Wuhan, Hubei, People’s Republic of China
- Sleep Medicine Centre, Zhongnan Hospital of Wuhan University, Wuhan, Hubei, People’s Republic of China
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Lv HY, Shi G, Li C, Ye YF, Chen YH, Chen LH, Tung TH, Zhang M. Association of SULT1A2 rs1059491 with obesity and dyslipidaemia in southern Chinese adults. Sci Rep 2023; 13:7256. [PMID: 37142702 PMCID: PMC10160091 DOI: 10.1038/s41598-023-34296-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2022] [Accepted: 04/27/2023] [Indexed: 05/06/2023] Open
Abstract
In the sulfotransferase (SULT) superfamily, members of the SULT1 family mainly catalyse the sulfonation reaction of phenolic compounds, which is involved in the phase II metabolic detoxification process and plays a key role in endocrine homeostasis. A coding variant rs1059491 in the SULT1A2 gene has been reported to be associated with childhood obesity. This study aimed to investigate the association of rs1059491 with the risk of obesity and cardiometabolic abnormalities in adults. This case‒control study included 226 normal weight, 168 overweight and 72 obese adults who underwent a health examination in Taizhou, China. Genotyping of rs1059491 was performed by Sanger sequencing in exon 7 of the SULT1A2 coding region. Chi-squared tests, one-way ANOVA, and logistic regression models were applied. The minor allele frequencies of rs1059491 in the overweight combined with obesity and control groups were 0.0292 and 0.0686, respectively. No differences in weight and body mass index were detected between the TT genotype and GT + GG genotype under the dominant model, but the levels of serum triglycerides were significantly lower in G-allele carriers than in non-G-allele carriers (1.02 (0.74-1.32) vs. 1.35 (0.83-2.13) mmol/L, P = 0.011). The GT + GG genotype of rs1059491 versus the TT genotype reduced the risk of overweight and obesity by 54% (OR 0.46, 95% CI 0.22-0.96, P = 0.037) after adjusting for sex and age. Similar results were observed for hypertriglyceridaemia (OR 0.25, 95% CI 0.08-0.74, P = 0.013) and dyslipidaemia (OR 0.37, 95% CI 0.17-0.83, P = 0.015). However, these associations disappeared after correction for multiple tests. This study revealed that the coding variant rs1059491 is nominally associated with a decreased risk of obesity and dyslipidaemia in southern Chinese adults. The findings will be validated in larger studies including more detailed information on genetic background, lifestyle and weight change with age.
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Affiliation(s)
- Hai-Yan Lv
- Department of Clinical Laboratory, Taizhou Hospital of Zhejiang Province Affiliated to Wenzhou Medical University, Linhai, 317000, Zhejiang, China
| | - Guifeng Shi
- Department of Preventive Health Care, Taizhou Hospital of Zhejiang Province Affiliated to Wenzhou Medical University, Linhai, 317000, Zhejiang, China
| | - Cai Li
- Department of Neurology, Taizhou Hospital of Zhejiang Province Affiliated to Wenzhou Medical University, Linhai, 317000, Zhejiang, China
| | - Ya-Fei Ye
- Health Management Centre, Taizhou Hospital of Zhejiang Province Affiliated to Wenzhou Medical University, Linhai, 317000, Zhejiang, China
| | - Ya-Hong Chen
- Health Management Centre, Taizhou Hospital of Zhejiang Province Affiliated to Wenzhou Medical University, Linhai, 317000, Zhejiang, China
| | - Li-Hua Chen
- Public Scientific Research Platform, Taizhou Hospital of Zhejiang Province Affiliated To Wenzhou Medical University, Linhai, 317000, Zhejiang, China
| | - Tao-Hsin Tung
- Evidence-Based Medicine Center, Taizhou Hospital of Zhejiang Province Affiliated to Wenzhou Medical University, No. 150, Ximen Street, Linhai, 317000, Zhejiang, China
| | - Meixian Zhang
- Evidence-Based Medicine Center, Taizhou Hospital of Zhejiang Province Affiliated to Wenzhou Medical University, No. 150, Ximen Street, Linhai, 317000, Zhejiang, China.
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Next-generation sequencing of 12 obesity genes in a Portuguese cohort of patients with overweight and obesity. Eur J Med Genet 2023; 66:104728. [PMID: 36775011 DOI: 10.1016/j.ejmg.2023.104728] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Revised: 12/28/2022] [Accepted: 02/10/2023] [Indexed: 02/12/2023]
Abstract
We examined 12 monogenic obesity genes in 72 Portuguese individuals with overweight and obesity (class 1 and class 2), some of which with suspected genetic obesity, to identify known or unknown potential obesity variants. Genomic DNA was analyzed for variants in genes LEP, LEPR, MC4R, POMC, PCSK1, BDNF, NTRK2, SIM1, SH2B1, UCP3, GCG and ADCY3 through next generation sequencing (NGS). The impact of the rare variants was investigated in the ClinVar database and using in silico tools for prediction of pathogenicity. Four potential pathogenic missense variants were detected at the heterozygous state in five individuals: two in the ADCY3 gene, NM_004036.5:c.1153G > A (p.Val385Ile) (rs756783003) and NM_004036.5:c.1222G > A (p.Gly408Arg) (rs201606553), one in gene SH2B1, NM_001145795.1:c.127C > A (p.Arg43Ser) (rs547678855), and the fourth in gene POMC NM_000939.4:c.706C > G (p.Arg236Gly) (rs28932472), which was found in two individuals. Moreover, six rare variants near splicing sites were also identified, as well as eight rare synonymous variants. In summary, some potential pathogenic rare missense variants were identified, two of them in ADCY3 gene, the most recently identified gene as having a role in monogenic obesity. Further analysis should be performed to confirm the clinical relevance of these variants.
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Argetsinger LS, Flores A, Svezhova N, Ellis M, Reynolds C, Cote JL, Cline JM, Myers MG, Carter-Su C. Role of the Beta and Gamma Isoforms of the Adapter Protein SH2B1 in Regulating Energy Balance. Endocrinology 2023; 164:bqad032. [PMID: 36799031 PMCID: PMC10282918 DOI: 10.1210/endocr/bqad032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Revised: 02/03/2023] [Accepted: 02/15/2023] [Indexed: 02/18/2023]
Abstract
Human variants of the adapter protein SH2B1 are associated with severe childhood obesity, hyperphagia, and insulin resistance-phenotypes mimicked by mice lacking Sh2b1. SH2B1β and γ isoforms are expressed ubiquitously, whereas SH2B1α and δ isoforms are expressed primarily in the brain. Restoring SH2B1β driven by the neuron-specific enolase promoter largely reverses the metabolic phenotype of Sh2b1-null mice, suggesting crucial roles for neuronal SH2B1β in energy balance control. Here we test this hypothesis by using CRISPR/Cas9 gene editing to delete the β and γ isoforms from the neurons of mice (SH2B1βγ neuron-specific knockout [NKO] mice) or throughout the body (SH2B1βγ knockout [KO] mice). While parameters of energy balance were normal in both male and female SH2B1βγ NKO mice, food intake, body weight, and adiposity were increased in male (but not female) SH2B1βγ KO mice. Analysis of long-read single-cell RNA seq data from wild-type mouse brain revealed that neurons express almost exclusively the α and δ isoforms, whereas neuroglial cells express almost exclusively the β and γ isoforms. Our work suggests that neuronal SH2B1β and γ are not primary regulators of energy balance. Rather, non-neuronal SH2B1β and γ in combination with neuronal SH2B1α and δ suffice for body weight maintenance. While SH2B1β/γ and SH2B1α/δ share some functionality, SH2B1β/γ appears to play a larger role in promoting leanness.
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Affiliation(s)
- Lawrence S Argetsinger
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI, 48109, USA
| | - Anabel Flores
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI, 48109, USA
| | - Nadezhda Svezhova
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI, 48109, USA
| | - Michael Ellis
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI, 48109, USA
| | - Caitlin Reynolds
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI, 48109, USA
| | - Jessica L Cote
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI, 48109, USA
- Neuroscience Graduate Program, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Joel M Cline
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI, 48109, USA
| | - Martin G Myers
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI, 48109, USA
- Neuroscience Graduate Program, University of Michigan, Ann Arbor, MI, 48109, USA
- Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, MI, 48109, USA
| | - Christin Carter-Su
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI, 48109, USA
- Neuroscience Graduate Program, University of Michigan, Ann Arbor, MI, 48109, USA
- Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, MI, 48109, USA
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SH2B1 variants as potential causes of non-syndromic monogenic obesity in a Brazilian cohort. Eat Weight Disord 2022; 27:3665-3674. [PMID: 36436143 DOI: 10.1007/s40519-022-01506-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Accepted: 10/29/2022] [Indexed: 11/28/2022] Open
Abstract
PURPOSE SH2B1 gene encodes an important adaptor protein to receptor tyrosine kinases or cytokine receptors associated with Janus kinases. This gene has been associated with the structural and functional modulation of neurons and other cells, and impacts on energy and glucose homeostasis. Several studies suggested that alterations in this gene are strong candidates for the development of obesity. However, only a few studies have screened SH2B1 point variants in individuals with obesity. Therefore, the aim of this study was to investigate the prevalence of SH2B1 variants in a Brazilian cohort of patients with severe obesity and candidates to bariatric surgery. METHODS The cohort comprised 122 individuals with severe obesity, who developed this phenotype during childhood. As controls, 100 normal-weight individuals were included. The coding region of SH2B1 gene was screened by Sanger sequencing. RESULTS A total of eight variants were identified in SH2B1, of which p.(Val345Met) and p.(Arg630Gln) variants were rare and predicted as potentially pathogenic by the in the silico algorithms used in this study. The p.(Val345Met) was not found in either the control group or in publicly available databases. This variant was identified in a female patient with severe obesity, metabolic syndrome and hyperglycemia. The p.(Arg630Gln) was also absent in our control group, but it was reported in gnomAD with an extremely low frequency. This variant was observed in a female patient with morbid obesity, metabolic syndrome, hypertension and severe binge-eating disorder. CONCLUSION Our study reported for the first time two rare and potentially pathogenic variants in Brazilian patients with severe obesity. Further functional studies will be necessary to confirm and elucidate the impact of these variants on SH2B1 protein function and stability, and their impact on energetic metabolism. LEVEL OF EVIDENCE Level V, cross-sectional descriptive study.
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Hinney A, Körner A, Fischer-Posovszky P. The promise of new anti-obesity therapies arising from knowledge of genetic obesity traits. Nat Rev Endocrinol 2022; 18:623-637. [PMID: 35902734 PMCID: PMC9330928 DOI: 10.1038/s41574-022-00716-0] [Citation(s) in RCA: 32] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 06/17/2022] [Indexed: 02/07/2023]
Abstract
Obesity is a multifactorial and complex disease that often manifests in early childhood with a lifelong burden. Polygenic and monogenic obesity are driven by the interaction between genetic predisposition and environmental factors. Polygenic variants are frequent and confer small effect sizes. Rare monogenic obesity syndromes are caused by defined pathogenic variants in single genes with large effect sizes. Most of these genes are involved in the central nervous regulation of body weight; for example, genes of the leptin-melanocortin pathway. Clinically, patients with monogenic obesity present with impaired satiety, hyperphagia and pronounced food-seeking behaviour in early childhood, which leads to severe early-onset obesity. With the advent of novel pharmacological treatment options emerging for monogenic obesity syndromes that target the central melanocortin pathway, genetic testing is recommended for patients with rapid weight gain in infancy and additional clinical suggestive features. Likewise, patients with obesity associated with hypothalamic damage or other forms of syndromic obesity involving energy regulatory circuits could benefit from these novel pharmacological treatment options. Early identification of patients affected by syndromic obesity will lead to appropriate treatment, thereby preventing the development of obesity sequelae, avoiding failure of conservative treatment approaches and alleviating stigmatization of patients and their families.
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Affiliation(s)
- Anke Hinney
- Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy and University Hospital Essen, University of Duisburg-Essen, Essen, Germany.
- Center for Translational Neuro- and Behavioral Sciences, University Hospital Essen, University of Duisburg-Essen, Essen, Germany.
| | - Antje Körner
- Leipzig University, Medical Faculty, Hospital for Children and Adolescents, Centre of Paediatric Research (CPL), Leipzig, Germany
- LIFE Child, Leipzig Research Centre for Civilization Diseases, Leipzig, Germany
- Helmholtz Institute for Metabolic, Obesity and Vascular Research (HI-MAG) of the Helmholtz Zentrum München at the University of Leipzig and University Hospital Leipzig, Leipzig, Germany
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Giannopoulou EZ, Zorn S, Schirmer M, Herrmann G, Heger S, Reinehr T, Denzer C, Rabenstein H, Hillmer M, Sowada N, Siebert R, von Schnurbein J, Wabitsch M. Genetic Obesity in Children: Overview of Possible Diagnoses with a Focus on SH2B1 Deletion. Horm Res Paediatr 2022; 95:137-148. [PMID: 34689140 DOI: 10.1159/000520402] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Accepted: 10/21/2021] [Indexed: 11/19/2022] Open
Abstract
INTRODUCTION Genetic obesity is rare and quite challenging for pediatricians in terms of early identification. Src-homology-2 (SH2) B adapter protein 1 (SH2B1) is an important component in the leptin-melanocortin pathway and is found to play an important role in leptin and insulin signaling and therefore in the pathogenesis of obesity and diabetes. Microdeletions in chromosome 16p11.2, encompassing the SH2B1 gene, are known to be associated with obesity, insulin resistance, hyperphagia, and developmental delay. The aim of our study is to report on a case series of young individuals with 16p11.2 microdeletions, including the SH2B1 gene, and provide detailed information on body mass index (BMI) development and obesity-associated comorbidities. In this way, we want to raise awareness of this syndromic form of obesity as a differential diagnosis of genetic obesity. METHODS We describe the phenotype of 7 children (3 male; age range: 2.8-18.0 years) with 16p11.2 microdeletions, encompassing the SH2B1 gene, and present their BMI trajectories from birth onward. Screening for obesity-associated comorbidities was performed at the time of genetic diagnosis. RESULTS All children presented with severe, early-onset obesity already at the age of 5 years combined with variable developmental delay. Five patients presented with elevated fasting insulin levels, 1 patient developed diabetes mellitus type 2, 4 patients had dyslipidemia, and 4 developed nonalcoholic fatty-liver disease. DISCUSSION/CONCLUSION Chromosomal microdeletions in 16p11.2, including the SH2B1 gene, in children are associated with severe, early-onset obesity and comorbidities associated with insulin resistance. Early genetic testing in suspicious patients and early screening for comorbidities are recommended.
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Affiliation(s)
- Eleni Z Giannopoulou
- Division of Pediatric Endocrinology and Diabetes, Department of Pediatrics and Adolescent Medicine, University Medical Center Ulm, Ulm, Germany
| | - Stefanie Zorn
- Division of Pediatric Endocrinology and Diabetes, Department of Pediatrics and Adolescent Medicine, University Medical Center Ulm, Ulm, Germany
| | - Melanie Schirmer
- Division of Pediatric Endocrinology and Diabetes, Department of Pediatrics and Adolescent Medicine, University Medical Center Ulm, Ulm, Germany
| | - Gloria Herrmann
- Division of Pediatric Endocrinology and Diabetes, Department of Pediatrics and Adolescent Medicine, University Medical Center Ulm, Ulm, Germany
| | - Sabine Heger
- Department of Pediatric Endocrinology, Children's Hospital Auf der Bult, Hannover, Germany
| | - Thomas Reinehr
- Department of Pediatric Endocrinology, Diabetes and Nutrition Medicine, Vestische Hospital for Children and Adolescents Datteln, University of Witten/Herdecke, Datteln, Germany
| | - Christian Denzer
- Division of Pediatric Endocrinology and Diabetes, Department of Pediatrics and Adolescent Medicine, University Medical Center Ulm, Ulm, Germany
| | - Hannah Rabenstein
- Institute of Human Genetics, Ulm University & Ulm University Medical Center, Ulm, Germany
| | - Morten Hillmer
- Institute of Human Genetics, Ulm University & Ulm University Medical Center, Ulm, Germany
| | - Nadine Sowada
- Institute of Human Genetics, Ulm University & Ulm University Medical Center, Ulm, Germany
| | - Reiner Siebert
- Institute of Human Genetics, Ulm University & Ulm University Medical Center, Ulm, Germany
| | - Julia von Schnurbein
- Division of Pediatric Endocrinology and Diabetes, Department of Pediatrics and Adolescent Medicine, University Medical Center Ulm, Ulm, Germany
| | - Martin Wabitsch
- Division of Pediatric Endocrinology and Diabetes, Department of Pediatrics and Adolescent Medicine, University Medical Center Ulm, Ulm, Germany
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Perez-Diaz-del-Campo N, Abete I, Cantero I, Marin-Alejandre BA, Monreal JI, Elorz M, Herrero JI, Benito-Boillos A, Riezu-Boj JI, Milagro FI, Tur JA, Martinez JA, Zulet MA. Association of the SH2B1 rs7359397 Gene Polymorphism with Steatosis Severity in Subjects with Obesity and Non-Alcoholic Fatty Liver Disease. Nutrients 2020; 12:nu12051260. [PMID: 32365683 PMCID: PMC7282006 DOI: 10.3390/nu12051260] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Revised: 04/24/2020] [Accepted: 04/27/2020] [Indexed: 12/12/2022] Open
Abstract
Non-alcoholic fatty liver disease (NAFLD) is a major cause of liver disease worldwide. Some genetic variants might be involved in the progression of this disease. The study hypothesized that individuals with the rs7359397 T allele have a higher risk of developing severe stages of NAFLD compared with non-carriers where dietary intake according to genotypes could have a key role on the pathogenesis of the disease. SH2B1 genetic variant was genotyped in 110 overweight/obese subjects with NAFLD. Imaging techniques, lipidomic analysis and blood liver biomarkers were performed. Body composition, general biochemical and dietary variables were also determined. The SH2B1 risk genotype was associated with higher HOMA-IR p = 0.001; and Fatty Liver Index (FLI) p = 0.032. Higher protein consumption (p = 0.028), less mono-unsaturated fatty acid and fiber intake (p = 0.045 and p = 0.049, respectively), was also referred to in risk allele genotype. Lipidomic analysis showed that T allele carriers presented a higher frequency of non-alcoholic steatohepatitis (NASH) (69.1% vs. 44.4%; p = 0.006). In the genotype risk group, adjusted logistic regression models indicated a higher risk of developing an advanced stage of NAFLD measured by FLI (OR 2.91) and ultrasonography (OR 4.15). Multinomial logistic regression models showed that risk allele carriers had higher liver fat accumulation risk (RRR 3.93) and an increased risk of NASH (RRR 7.88). Consequently, subjects carrying the T allele were associated with a higher risk of developing a severe stage of NAFLD. These results support the importance of considering genetic predisposition in combination with a healthy dietary pattern in the personalized evaluation and management of NAFLD.
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Affiliation(s)
- Nuria Perez-Diaz-del-Campo
- Department of Nutrition, Food Science and Physiology, Faculty of Pharmacy and Nutrition, University of Navarra, 31008 Pamplona, Spain; (N.P-D.-d.-C.); (I.C.); (B.A.M.-A.); (J.I.R.-B.); (F.I.M.); (J.A.M.)
- Centre for Nutrition Research, Faculty of Pharmacy and Nutrition, University of Navarra, 31008 Pamplona, Spain
| | - Itziar Abete
- Department of Nutrition, Food Science and Physiology, Faculty of Pharmacy and Nutrition, University of Navarra, 31008 Pamplona, Spain; (N.P-D.-d.-C.); (I.C.); (B.A.M.-A.); (J.I.R.-B.); (F.I.M.); (J.A.M.)
- Centre for Nutrition Research, Faculty of Pharmacy and Nutrition, University of Navarra, 31008 Pamplona, Spain
- Biomedical Research Centre Network in Physiopathology of Obesity and Nutrition (CIBERobn), Instituto de Salud Carlos III, 28029 Madrid, Spain;
- Navarra Institute for Health Research (IdiSNA), 31008 Pamplona, Spain; (J.I.M.); (M.E.); (J.I.H.); (A.B.-B.)
- Correspondence: (I.A.); (M.A.Z.); Tel.: +34-948-25-60-00 (I.A.)
| | - Irene Cantero
- Department of Nutrition, Food Science and Physiology, Faculty of Pharmacy and Nutrition, University of Navarra, 31008 Pamplona, Spain; (N.P-D.-d.-C.); (I.C.); (B.A.M.-A.); (J.I.R.-B.); (F.I.M.); (J.A.M.)
- Centre for Nutrition Research, Faculty of Pharmacy and Nutrition, University of Navarra, 31008 Pamplona, Spain
| | - Bertha Araceli Marin-Alejandre
- Department of Nutrition, Food Science and Physiology, Faculty of Pharmacy and Nutrition, University of Navarra, 31008 Pamplona, Spain; (N.P-D.-d.-C.); (I.C.); (B.A.M.-A.); (J.I.R.-B.); (F.I.M.); (J.A.M.)
- Centre for Nutrition Research, Faculty of Pharmacy and Nutrition, University of Navarra, 31008 Pamplona, Spain
| | - J. Ignacio Monreal
- Navarra Institute for Health Research (IdiSNA), 31008 Pamplona, Spain; (J.I.M.); (M.E.); (J.I.H.); (A.B.-B.)
- Clinical Chemistry Department, Clínica Universidad de Navarra, 31008 Pamplona, Spain
| | - Mariana Elorz
- Navarra Institute for Health Research (IdiSNA), 31008 Pamplona, Spain; (J.I.M.); (M.E.); (J.I.H.); (A.B.-B.)
- Department of Radiology, Clínica Universidad de Navarra, 31008 Pamplona, Spain
| | - José Ignacio Herrero
- Navarra Institute for Health Research (IdiSNA), 31008 Pamplona, Spain; (J.I.M.); (M.E.); (J.I.H.); (A.B.-B.)
- Liver Unit, Clinica Universidad de Navarra, 31008 Pamplona, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), 28029 Madrid, Spain
| | - Alberto Benito-Boillos
- Navarra Institute for Health Research (IdiSNA), 31008 Pamplona, Spain; (J.I.M.); (M.E.); (J.I.H.); (A.B.-B.)
- Department of Radiology, Clínica Universidad de Navarra, 31008 Pamplona, Spain
| | - Jose I. Riezu-Boj
- Department of Nutrition, Food Science and Physiology, Faculty of Pharmacy and Nutrition, University of Navarra, 31008 Pamplona, Spain; (N.P-D.-d.-C.); (I.C.); (B.A.M.-A.); (J.I.R.-B.); (F.I.M.); (J.A.M.)
- Centre for Nutrition Research, Faculty of Pharmacy and Nutrition, University of Navarra, 31008 Pamplona, Spain
- Navarra Institute for Health Research (IdiSNA), 31008 Pamplona, Spain; (J.I.M.); (M.E.); (J.I.H.); (A.B.-B.)
| | - Fermín I. Milagro
- Department of Nutrition, Food Science and Physiology, Faculty of Pharmacy and Nutrition, University of Navarra, 31008 Pamplona, Spain; (N.P-D.-d.-C.); (I.C.); (B.A.M.-A.); (J.I.R.-B.); (F.I.M.); (J.A.M.)
- Centre for Nutrition Research, Faculty of Pharmacy and Nutrition, University of Navarra, 31008 Pamplona, Spain
- Biomedical Research Centre Network in Physiopathology of Obesity and Nutrition (CIBERobn), Instituto de Salud Carlos III, 28029 Madrid, Spain;
- Navarra Institute for Health Research (IdiSNA), 31008 Pamplona, Spain; (J.I.M.); (M.E.); (J.I.H.); (A.B.-B.)
| | - Josep A. Tur
- Biomedical Research Centre Network in Physiopathology of Obesity and Nutrition (CIBERobn), Instituto de Salud Carlos III, 28029 Madrid, Spain;
- Research Group on Community Nutrition and Oxidative Stress, University of Balearic Islands & Balearic Islands Institute for Health Research (IDISBA), 07122 Palma, Spain
| | - J. Alfredo Martinez
- Department of Nutrition, Food Science and Physiology, Faculty of Pharmacy and Nutrition, University of Navarra, 31008 Pamplona, Spain; (N.P-D.-d.-C.); (I.C.); (B.A.M.-A.); (J.I.R.-B.); (F.I.M.); (J.A.M.)
- Centre for Nutrition Research, Faculty of Pharmacy and Nutrition, University of Navarra, 31008 Pamplona, Spain
- Biomedical Research Centre Network in Physiopathology of Obesity and Nutrition (CIBERobn), Instituto de Salud Carlos III, 28029 Madrid, Spain;
- Navarra Institute for Health Research (IdiSNA), 31008 Pamplona, Spain; (J.I.M.); (M.E.); (J.I.H.); (A.B.-B.)
| | - M. Angeles Zulet
- Department of Nutrition, Food Science and Physiology, Faculty of Pharmacy and Nutrition, University of Navarra, 31008 Pamplona, Spain; (N.P-D.-d.-C.); (I.C.); (B.A.M.-A.); (J.I.R.-B.); (F.I.M.); (J.A.M.)
- Centre for Nutrition Research, Faculty of Pharmacy and Nutrition, University of Navarra, 31008 Pamplona, Spain
- Biomedical Research Centre Network in Physiopathology of Obesity and Nutrition (CIBERobn), Instituto de Salud Carlos III, 28029 Madrid, Spain;
- Navarra Institute for Health Research (IdiSNA), 31008 Pamplona, Spain; (J.I.M.); (M.E.); (J.I.H.); (A.B.-B.)
- Correspondence: (I.A.); (M.A.Z.); Tel.: +34-948-25-60-00 (I.A.)
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Peters T, Nüllig L, Antel J, Naaresh R, Laabs BH, Tegeler L, Amhaouach C, Libuda L, Hinney A, Hebebrand J. The Role of Genetic Variation of BMI, Body Composition, and Fat Distribution for Mental Traits and Disorders: A Look-Up and Mendelian Randomization Study. Front Genet 2020; 11:373. [PMID: 32373164 PMCID: PMC7186862 DOI: 10.3389/fgene.2020.00373] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Accepted: 03/26/2020] [Indexed: 12/22/2022] Open
Abstract
Anthropometric traits and mental disorders or traits are known to be associated clinically and to show genetic overlap. We aimed to identify genetic variants with relevance for mental disorders/traits and either (i) body mass index (or obesity), (ii) body composition, (and/or) (iii) body fat distribution. We performed a look-up analysis of 1,005 genome-wide significant SNPs for BMI, body composition, and body fat distribution in 15 mental disorders/traits. We identified 40 independent loci with one or more SNPs fulfilling our threshold significance criterion (P < 4.98 × 10–5) for the mental phenotypes. The majority of loci was associated with schizophrenia, educational attainment, and/or intelligence. Fewer associations were found for bipolar disorder, neuroticism, attention deficit/hyperactivity disorder, major depressive disorder, depressive symptoms, and well-being. Unique associations with measures of body fat distribution adjusted for BMI were identified at five loci only. To investigate the potential causality between body fat distribution and schizophrenia, we performed two-sample Mendelian randomization analyses. We found no causal effect of body fat distribution on schizophrenia and vice versa. In conclusion, we identified 40 loci which may contribute to genetic overlaps between mental disorders/traits and BMI and/or shape related phenotypes. The majority of loci identified for body composition overlapped with BMI loci, thus suggesting pleiotropic effects.
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Affiliation(s)
- Triinu Peters
- Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Lena Nüllig
- Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Jochen Antel
- Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Roaa Naaresh
- Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Björn-Hergen Laabs
- Institute of Medical Biometry and Statistics, University of Lübeck, University Hospital Schleswig-Holstein, Lübeck, Germany
| | - Lisa Tegeler
- Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Chaima Amhaouach
- Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Lars Libuda
- Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Anke Hinney
- Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Johannes Hebebrand
- Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
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Leptin receptor-expressing neuron Sh2b1 supports sympathetic nervous system and protects against obesity and metabolic disease. Nat Commun 2020; 11:1517. [PMID: 32251290 PMCID: PMC7089966 DOI: 10.1038/s41467-020-15328-3] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Accepted: 03/03/2020] [Indexed: 01/08/2023] Open
Abstract
Leptin stimulates the sympathetic nervous system (SNS), energy expenditure, and weight loss; however, the underlying molecular mechanism remains elusive. Here, we uncover Sh2b1 in leptin receptor (LepR) neurons as a critical component of a SNS/brown adipose tissue (BAT)/thermogenesis axis. LepR neuron-specific deletion of Sh2b1 abrogates leptin-stimulated sympathetic nerve activation and impairs BAT thermogenic programs, leading to reduced core body temperature and cold intolerance. The adipose SNS degenerates progressively in mutant mice after 8 weeks of age. Adult-onset ablation of Sh2b1 in the mediobasal hypothalamus also impairs the SNS/BAT/thermogenesis axis; conversely, hypothalamic overexpression of human SH2B1 has the opposite effects. Mice with either LepR neuron-specific or adult-onset, hypothalamus-specific ablation of Sh2b1 develop obesity, insulin resistance, and liver steatosis. In contrast, hypothalamic overexpression of SH2B1 protects against high fat diet-induced obesity and metabolic syndromes. Our results unravel an unrecognized LepR neuron Sh2b1/SNS/BAT/thermogenesis axis that combats obesity and metabolic disease.
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Open Chromatin Profiling in Adipose Tissue Marks Genomic Regions with Functional Roles in Cardiometabolic Traits. G3-GENES GENOMES GENETICS 2019; 9:2521-2533. [PMID: 31186305 PMCID: PMC6686932 DOI: 10.1534/g3.119.400294] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Identifying the regulatory mechanisms of genome-wide association study (GWAS) loci affecting adipose tissue has been restricted due to limited characterization of adipose transcriptional regulatory elements. We profiled chromatin accessibility in three frozen human subcutaneous adipose tissue needle biopsies and preadipocytes and adipocytes from the Simpson Golabi-Behmel Syndrome (SGBS) cell strain using an assay for transposase-accessible chromatin (ATAC-seq). We identified 68,571 representative accessible chromatin regions (peaks) across adipose tissue samples (FDR < 5%). GWAS loci for eight cardiometabolic traits were enriched in these peaks (P < 0.005), with the strongest enrichment for waist-hip ratio. Of 110 recently described cardiometabolic GWAS loci colocalized with adipose tissue eQTLs, 59 loci had one or more variants overlapping an adipose tissue peak. Annotated variants at the SNX10 waist-hip ratio locus and the ATP2A1-SH2B1 body mass index locus showed allelic differences in regulatory assays. These adipose tissue accessible chromatin regions elucidate genetic variants that may alter adipose tissue function to impact cardiometabolic traits.
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12
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Hammarén HM, Virtanen AT, Raivola J, Silvennoinen O. The regulation of JAKs in cytokine signaling and its breakdown in disease. Cytokine 2019; 118:48-63. [DOI: 10.1016/j.cyto.2018.03.041] [Citation(s) in RCA: 83] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Revised: 03/29/2018] [Accepted: 03/30/2018] [Indexed: 01/12/2023]
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Giuranna J, Volckmar AL, Heinen A, Peters T, Schmidt B, Spieker A, Straub H, Grallert H, Müller TD, Antel J, Haußmann U, Klafki H, Liangyou R, Hebebrand J, Hinney A. The Effect of SH2B1 Variants on Expression of Leptin- and Insulin-Induced Pathways in Murine Hypothalamus. Obes Facts 2018; 11:93-108. [PMID: 29631267 PMCID: PMC5981666 DOI: 10.1159/000486962] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/14/2017] [Accepted: 01/15/2018] [Indexed: 12/30/2022] Open
Abstract
OBJECTIVE We aimed to determine the effect of human SH2B1 variants on leptin and insulin signaling, major regulators of energy homeostasis, on the RNA level. METHODS We analyzed the expression of infrequent alleles of seven SH2B1 variants (Arg67Cys, Lys150Arg, Thr175Ala, Thr343Met, Thr484Ala, Ser616Pro and Pro689Leu) in response to insulin or leptin cell stimulation. Two of these were identified in own mutation screens, the others were predicted to be deleterious or to serve as controls. The variants were analyzed in a homologous system of mouse hypothalamic cells. Changes in expression of downstream genes were measured. Student’s t-test for independent samples was applied and effect sizes using Cohen’s d were calculated. RESULTS In 34 of 54 analyzed genes involved in leptin (JAK/STAT or AKT) signaling, variants nominally changed expression. The expression of three genes was considerably increased (p values ≤ 0.001: Gbp2b (67Cys; d = 25.11), Irf9 (689Leu; d = 44.65) and Isg15 (150Arg; d = 20.35)). Of 32 analyzed genes in the insulin signaling pathway, the expression of 10 genes nominally changed (p ≤ 0.05), three resulted in p values ≤ 0.01 ( Cap1 (150Arg; d = 7.48), Mapk1 (343Met; d = –6.80) and Sorbs1 (689Leu; d = 7.82)). CONCLUSION The increased expression of genes in leptin (JAK/STAT or AKT) signaling implies that the main mode of action for human SH2B1 mutations might affect leptin signaling rather than insulin signaling.
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Affiliation(s)
- Johanna Giuranna
- Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Anna-Lena Volckmar
- Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
- Institute of Pathology, Heidelberg University Hospital, Heidelberg, Germany
| | - Anna Heinen
- Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Triinu Peters
- Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Börge Schmidt
- Institute for Medical Informatics, Biometry and Epidemiology (IMIBE), University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Anne Spieker
- Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Helena Straub
- Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Harald Grallert
- Institute of Epidemiology, Helmholtz-Zentrum Munich, Munich, Germany
| | - Timo D. Müller
- Institute of Diabetes and Obesity, Helmholtz-Zentrum Munich, Munich, Germany
| | - Jochen Antel
- Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Ute Haußmann
- Department of Psychiatry and Psychotherapy, Faculty of Medicine, University Hospital Essen, Essen, Germany
| | - Hans Klafki
- Department of Psychiatry and Psychotherapy, Faculty of Medicine, University Hospital Essen, Essen, Germany
- Department of Psychiatry and Psychotherapy, University Medical Center Göttingen (UMG), Georg-August-University Göttingen, Göttingen, Germany
| | - Rui Liangyou
- Molecular & Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Johannes Hebebrand
- Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Anke Hinney
- Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
- *Prof. Dr. Anke Hinney, Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, University Hospital Essen, University of Duisburg-Essen, Wickenburgstraße 21, 45147 Essen, Germany,
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Abstract
Zusammenfassung
Autosomal-rezessiv vererbte Mutationen in den Genen für Leptin, Leptinrezeptor, Proopiomelanocortin (POMC) und Prohormon-Convertase (PC1) führen zu einer ausgeprägten frühkindlichen Adipositas. Patienten mit biologisch inaktivem Leptin oder Leptinmangel können mit humanem rekombinanten Leptin erfolgreich behandelt werden. Für die anderen Patienten hat sich die Behandlung mit einem α‑MSH-Analogon als erfolgreich erwiesen (POMC-Patienten) bzw. befindet sich derzeit in Erprobung.
Kodominant vererbte Mutationen im MC4R-Gen stellen die häufigste Form der monogenen Adipositas dar. Eine kausale Therapie ist hier allerdings nicht möglich.
Es sind inzwischen noch weitere, autosomal-rezessiv vererbte Genmutationen identifiziert worden, die ebenfalls mit einer ausgeprägten Adipositas assoziiert sind. Die meisten dieser Mutationen liegen in Genen, die in die Signaltransduktion von MC4R oder dem Leptinrezeptor involviert sind. Auch für diese Patienten gibt es aktuell noch keine kausale Therapie.
Schlussfolgerung: Bei Patienten mit extremer frühkindlicher Adipositas sollte eine molekulargenetische Diagnostik eingeleitet werden, da die Diagnosestellung für die Betroffenen und ihre Familie eine enorme Erleichterung bedeuten kann. Außerdem gewinnen die Familien Klarheit über das Wiederholungsrisiko und eventuell ist sogar eine kausale oder zumindest optimierte Therapie möglich.
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Affiliation(s)
- Julia von Schnurbein
- Aff1 grid.410712.1 Klinik für Kinder- und Jugendmedizin, Zentrum für Seltene Erkrankungen (ZSE) Ulm, Sektion Pädiatrische Endokrinologie und Diabetologie Universitätsklinik für Kinder- und Jugendmedizin Eythstr. 24 89075 Ulm Deutschland
| | - Martin Wabitsch
- Aff1 grid.410712.1 Klinik für Kinder- und Jugendmedizin, Zentrum für Seltene Erkrankungen (ZSE) Ulm, Sektion Pädiatrische Endokrinologie und Diabetologie Universitätsklinik für Kinder- und Jugendmedizin Eythstr. 24 89075 Ulm Deutschland
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Hu G, Li P, Li Y, Wang T, Gao X, Zhang W, Jia G. Methylation levels of P16 and TP53 that are involved in DNA strand breakage of 16HBE cells treated by hexavalent chromium. Toxicol Lett 2016; 249:15-21. [DOI: 10.1016/j.toxlet.2016.03.003] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2015] [Revised: 01/19/2016] [Accepted: 03/07/2016] [Indexed: 01/10/2023]
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16
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Aerts E, Beckers S, Zegers D, Van Camp JK, Van Hoorenbeeck K, Massa G, Verrijken A, Mertens IL, Verhulst SL, Rooman RR, Van Gaal LF, Van Hul W. Genetic and structural variation in the SH2B1 gene in the Belgian population. Mol Genet Metab 2015; 115:193-8. [PMID: 26031769 DOI: 10.1016/j.ymgme.2015.05.010] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/24/2015] [Revised: 05/21/2015] [Accepted: 05/21/2015] [Indexed: 10/23/2022]
Abstract
OBJECTIVE Animal studies, genome-wide association and genomic structural variation studies have identified the SH2B1 gene as a candidate gene for obesity. Therefore, we have designed an extensive mutation and copy number variation (CNV) analysis investigating the prevalence of genetic and structural variations in SH2B1 in the Belgian population. DESIGN AND METHODS In the first part of this study, we performed a mutation screen for variants in the SH2B1 coding region in 581 obese children and adolescents and 433 healthy, lean individuals with high-resolution melting curve analysis followed by direct sequencing. In the second part of this study, Multiplex Amplicon Quantification (MAQ) analysis was used to identify CNVs in the distal SH2B1-containing chr.16p11.2 region in 421 obese children and adolescents with no developmental delay or behavioral phenotype. RESULTS Mutation analysis resulted in the identification of fifteen rare non-synonymous heterozygous variants. Several of these were found both in lean and obese subjects, suggesting that these are neutral polymorphisms. However, six private, heterozygous, non-synonymous variations were present in obese children only. Furthermore, we also identified six missense variants solely in lean individuals. CNV analysis could not identify carriers of the distal 16p11.2 deletion in our population. CONCLUSION Our mutation analysis has demonstrated that variation in the SH2B1 gene is frequent in both lean and obese groups, with distinctive variations being present on either side of the weight spectrum. Although the equal variation frequency does not immediately support disease causality, it cannot be excluded that some variations are weight-increasing or -decreasing. Further functional testing of the variants will be necessary to fully understand the impact of these variants on SH2B1. We were not able to detect carriers of the distal 16p11.2 deletion in our study population. As we excluded patients with developmental or behavioral problems, we suggest that in addition to obesity, the distal deletion might predispose for these traits. Further characterization of the phenotype is therefore necessary to clearly identify the phenotype of the distal 16p11.2 microdeletion syndrome.
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Affiliation(s)
- Evi Aerts
- Centre of Medical Genetics, University of Antwerp, Antwerp, Belgium
| | - Sigri Beckers
- Centre of Medical Genetics, University of Antwerp, Antwerp, Belgium
| | - Doreen Zegers
- Centre of Medical Genetics, University of Antwerp, Antwerp, Belgium
| | | | | | - Guy Massa
- Department of Pediatrics, Jessa Hospital, Hasselt, Belgium
| | - An Verrijken
- Department of Endocrinology, Diabetology and Metabolic Diseases, Antwerp University Hospital, Antwerp, Belgium
| | - Ilse L Mertens
- Department of Endocrinology, Diabetology and Metabolic Diseases, Antwerp University Hospital, Antwerp, Belgium
| | - Stijn L Verhulst
- Department of Pediatrics, Antwerp University Hospital, Antwerp, Belgium
| | - Raoul R Rooman
- Department of Pediatrics, Antwerp University Hospital, Antwerp, Belgium
| | - Luc F Van Gaal
- Department of Endocrinology, Diabetology and Metabolic Diseases, Antwerp University Hospital, Antwerp, Belgium
| | - Wim Van Hul
- Centre of Medical Genetics, University of Antwerp, Antwerp, Belgium.
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Fine Mapping of a GWAS-Derived Obesity Candidate Region on Chromosome 16p11.2. PLoS One 2015; 10:e0125660. [PMID: 25955518 PMCID: PMC4425372 DOI: 10.1371/journal.pone.0125660] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2014] [Accepted: 03/17/2015] [Indexed: 11/19/2022] Open
Abstract
INTRODUCTION Large-scale genome-wide association studies (GWASs) have identified 97 chromosomal loci associated with increased body mass index in population-based studies on adults. One of these SNPs, rs7359397, tags a large region (approx. 1MB) with high linkage disequilibrium (r2>0.7), which comprises five genes (SH2B1, APOBR, sulfotransferases: SULT1A1 and SULT1A2, TUFM). We had previously described a rare mutation in SH2B1 solely identified in extremely obese individuals but not in lean controls. METHODS The coding regions of the genes APOBR, SULT1A1, SULT1A2, and TUFM were screened for mutations (dHPLC, SSCP, Sanger re-sequencing) in 95 extremely obese children and adolescents. Detected non-synonymous variants were genotyped (TaqMan SNP Genotyping, MALDI TOF, PCR-RFLP) in independent large study groups (up to 3,210 extremely obese/overweight cases, 485 lean controls and 615 obesity trios). In silico tools were used for the prediction of potential functional effects of detected variants. RESULTS Except for TUFM we detected non-synonymous variants in all screened genes. Two polymorphisms rs180743 (APOBR p.Pro428Ala) and rs3833080 (APOBR p.Gly369_Asp370del9) showed nominal association to (extreme) obesity (uncorrected p = 0.003 and p = 0.002, respectively). In silico analyses predicted a functional implication for rs180743 (APOBR p.Pro428Ala). Both APOBR variants are located in the repetitive region with unknown function. CONCLUSION Variants in APOBR contributed as strongly as variants in SH2B1 to the association with extreme obesity in the chromosomal region chr16p11.2. In silico analyses implied no functional effect of several of the detected variants. Further in vitro or in vivo analyses on the functional implications of the obesity associated variants are warranted.
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Chen CJ, Shih CH, Chang YJ, Hong SJ, Li TN, Wang LHC, Chen L. SH2B1 and IRSp53 proteins promote the formation of dendrites and dendritic branches. J Biol Chem 2015; 290:6010-21. [PMID: 25586189 DOI: 10.1074/jbc.m114.603795] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
SH2B1 is an adaptor protein known to enhance neurite outgrowth. In this study, we provide evidence suggesting that the SH2B1 level is increased during in vitro culture of hippocampal neurons, and the β isoform (SH2B1β) is the predominant isoform. The fact that formation of filopodia is prerequisite for neurite initiation suggests that SH2B1 may regulate filopodium formation and thus neurite initiation. To investigate whether SH2B1 may regulate filopodium formation, the effect of SH2B1 and a membrane and actin regulator, IRSp53 (insulin receptor tyrosine kinase substrate p53), is investigated. Overexpressing both SH2B1β and IRSp53 significantly enhances filopodium formation, neurite outgrowth, and branching. Both in vivo and in vitro data show that SH2B1 interacts with IRSp53 in hippocampal neurons. This interaction depends on the N-terminal proline-rich domains of SH2B1. In addition, SH2B1 and IRSp53 co-localize at the plasma membrane, and their levels increase in the Triton X-100-insoluble fraction of developing neurons. These findings suggest that SH2B1-IRSp53 complexes promote the formation of filopodia, neurite initiation, and neuronal branching.
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Affiliation(s)
| | | | | | | | | | - Lily Hui-Ching Wang
- Institute of Molecular and Cellular Biology, Department of Medical Science, National Tsing Hua University, Hsinchu, Taiwan 30013, China
| | - Linyi Chen
- From the Institute of Molecular Medicine, Department of Medical Science, National Tsing Hua University, Hsinchu, Taiwan 30013, China
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Pearce LR, Joe R, Doche ME, Su HW, Keogh JM, Henning E, Argetsinger LS, Bochukova EG, Cline JM, Garg S, Saeed S, Shoelson S, O'Rahilly S, Barroso I, Rui L, Farooqi IS, Carter-Su C. Functional characterization of obesity-associated variants involving the α and β isoforms of human SH2B1. Endocrinology 2014; 155:3219-26. [PMID: 24971614 PMCID: PMC4138566 DOI: 10.1210/en.2014-1264] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We have previously reported rare variants in sarcoma (Src) homology 2 (SH2) B adaptor protein 1 (SH2B1) in individuals with obesity, insulin resistance, and maladaptive behavior. Here, we identify 4 additional SH2B1 variants by sequencing 500 individuals with severe early-onset obesity. SH2B1 has 4 alternatively spliced isoforms. One variant (T546A) lies within the N-terminal region common to all isoforms. As shown for past variants in this region, T546A impairs SH2B1β enhancement of nerve growth factor-induced neurite outgrowth, and the individual with the T546A variant exhibits mild developmental delay. The other 3 variants (A663V, V695M, and A723V) lie in the C-terminal tail of SH2B1α. SH2B1α variant carriers were hyperinsulinemic but did not exhibit the behavioral phenotype observed in individuals with SH2B1 variants that disrupt all isoforms. In in vitro assays, SH2B1α, like SH2B1β, enhances insulin- and leptin-induced insulin receptor substrate 2 (IRS2) phosphorylation and GH-induced cell motility. None of the variants affect SH2B1α enhancement of insulin- and leptin-induced IRS2 phosphorylation. However, T546A, A663V, and A723V all impair the ability of SH2B1α to enhance GH-induced cell motility. In contrast to SH2B1β, SH2B1α does not enhance nerve growth factor-induced neurite outgrowth. These studies suggest that genetic variants that disrupt isoforms other than SH2B1β may be functionally significant. Further studies are needed to understand the mechanism by which the individual isoforms regulate energy homeostasis and behavior.
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Rui L. SH2B1 regulation of energy balance, body weight, and glucose metabolism. World J Diabetes 2014; 5:511-526. [PMID: 25126397 PMCID: PMC4127586 DOI: 10.4239/wjd.v5.i4.511] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/25/2013] [Revised: 03/06/2014] [Accepted: 06/03/2014] [Indexed: 02/05/2023] Open
Abstract
The Src homology 2B (SH2B) family members (SH2B1, SH2B2 and SH2B3) are adaptor signaling proteins containing characteristic SH2 and PH domains. SH2B1 (also called SH2-B and PSM) and SH2B2 (also called APS) are able to form homo- or hetero-dimers via their N-terminal dimerization domains. Their C-terminal SH2 domains bind to tyrosyl phosphorylated proteins, including Janus kinase 2 (JAK2), TrkA, insulin receptors, insulin-like growth factor-1 receptors, insulin receptor substrate-1 (IRS1), and IRS2. SH2B1 enhances leptin signaling by both stimulating JAK2 activity and assembling a JAK2/IRS1/2 signaling complex. SH2B1 promotes insulin signaling by both enhancing insulin receptor catalytic activity and protecting against dephosphorylation of IRS proteins. Accordingly, genetic deletion of SH2B1 results in severe leptin resistance, insulin resistance, hyperphagia, obesity, and type 2 diabetes in mice. Neuron-specific overexpression of SH2B1β transgenes protects against diet-induced obesity and insulin resistance. SH2B1 in pancreatic β cells promotes β cell expansion and insulin secretion to counteract insulin resistance in obesity. Moreover, numerous SH2B1 mutations are genetically linked to leptin resistance, insulin resistance, obesity, and type 2 diabetes in humans. Unlike SH2B1, SH2B2 and SH2B3 are not required for the maintenance of normal energy and glucose homeostasis. The metabolic function of the SH2B family is conserved from insects to humans.
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Implication of SH2B1 gene polymorphism studies in gestational diabetes mellitus in Saudi pregnant women. Saudi J Biol Sci 2014; 21:610-5. [PMID: 25473371 DOI: 10.1016/j.sjbs.2014.07.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2014] [Revised: 07/17/2014] [Accepted: 07/27/2014] [Indexed: 12/13/2022] Open
Abstract
Genome-wide association studies have identified loci that are firmly associated with obesity. The Src-homology-2 B adaptor protein 1 (SH2B1) loci is abundantly expressed in the brain, liver, heart, muscle, and fat tissues. Gestational diabetes mellitus (GDM) is a growing health concern that usually appears during the latter half of pregnancy, and it is characterized by carbohydrate intolerance of variable severity. The SH2B1 gene polymorphism has been linked with an increased risk of weight gain in several but not all population studies. This study aimed to investigate the genetic association of rs4788102 variants in the SH2B1 gene with GDM in Saudi pregnant women. Genomic DNA samples from 200 women with GDM and 300 women without GDM were genotyped using the TaqMan method. The distribution of the GG, GA, and AA genotypes was significantly different between GDM and non-GDM women (p < 0.05). Thus, we identified rs4788102 variants as additional risk factors for GDM in Saudi women, and we suggest that these variants may have a prognostic value.
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Richardson AS, North KE, Graff M, Young KM, Mohlke KL, Lange LA, Lange EM, Harris KM, Gordon-Larsen P. Moderate to vigorous physical activity interactions with genetic variants and body mass index in a large US ethnically diverse cohort. Pediatr Obes 2014; 9:e35-46. [PMID: 23529959 PMCID: PMC3707946 DOI: 10.1111/j.2047-6310.2013.00152.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/17/2012] [Revised: 02/06/2013] [Accepted: 01/31/2013] [Indexed: 12/23/2022]
Abstract
BACKGROUND Little is known about the interaction between genetic and behavioural factors during lifecycle risk periods for obesity and how associations vary across race/ethnicity. OBJECTIVE The objective of this study was to examine joint associations of adiposity-related single-nucleotide polymorphisms (SNPs) and moderate to vigorous physical activity (MVPA) with body mass index (BMI) in a diverse adolescent cohort. METHODS Using data from the National Longitudinal Study of Adolescent Health (n = 8113: Wave II 1996; ages 12-21, Wave III; ages 18-27), we assessed interactions of 41 well-established SNPs and MVPA with BMI-for-age Z-scores in European Americans (EA; n = 5077), African-Americans (AA; n = 1736) and Hispanic Americans (HA; n = 1300). RESULTS Of 97 assessed, we found nominally significant SNP-MVPA interactions on BMI-for-age Z-score in EA at GNPDA2 and FTO and in HA at LZTR2/SEC16B. In EA, the estimated effect of the FTO risk allele on BMI-for-age Z-score was lower (β = -0.13; 95% confidence interval [CI]: 0.08, 0.18) in individuals with ≥5 vs. <5 (β = 0.24; CI: 0.16, 0.32) bouts of MVPA per week (P for interaction 0.02). Race/ethnicity-pooled meta-analysis showed nominally significant interactions for SNPs at TFAP2B, POC5 and LYPLAL1. CONCLUSIONS High MVPA may attenuate underlying genetic risk for obesity during adolescence, a high-risk period for adult obesity.
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Affiliation(s)
- AS Richardson
- Carolina Population Center, University of North Carolina, Chapel Hill, North Carolina, USA,Department of Nutrition Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina, USA
| | - KE North
- Carolina Center for Genome Sciences, University of North Carolina, Chapel Hill, North Carolina, USA,Department of Epidemiology, University of North Carolina, Chapel Hill, North Carolina, USA
| | - M Graff
- Carolina Population Center, University of North Carolina, Chapel Hill, North Carolina, USA,Department of Epidemiology, University of North Carolina, Chapel Hill, North Carolina, USA
| | - KM Young
- Carolina Population Center, University of North Carolina, Chapel Hill, North Carolina, USA,Department of Epidemiology, University of North Carolina, Chapel Hill, North Carolina, USA
| | - KL Mohlke
- Carolina Center for Genome Sciences, University of North Carolina, Chapel Hill, North Carolina, USA,Department of Genetics, University of North Carolina, Chapel Hill, North Carolina, USA
| | - LA Lange
- Carolina Center for Genome Sciences, University of North Carolina, Chapel Hill, North Carolina, USA,Department of Genetics, University of North Carolina, Chapel Hill, North Carolina, USA
| | - EM Lange
- Carolina Center for Genome Sciences, University of North Carolina, Chapel Hill, North Carolina, USA,Department of Genetics, University of North Carolina, Chapel Hill, North Carolina, USA
| | - KM Harris
- Carolina Population Center, University of North Carolina, Chapel Hill, North Carolina, USA,Department of Sociology, North Carolina, USA
| | - P Gordon-Larsen
- Carolina Population Center, University of North Carolina, Chapel Hill, North Carolina, USA,Department of Nutrition Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina, USA
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Chen Z, Morris DL, Jiang L, Liu Y, Rui L. SH2B1 in β-cells regulates glucose metabolism by promoting β-cell survival and islet expansion. Diabetes 2014; 63:585-95. [PMID: 24150605 PMCID: PMC3900537 DOI: 10.2337/db13-0666] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
IGF-1 and insulin promote β-cell expansion by inhibiting β-cell death and stimulating β-cell proliferation, and the phosphatidylinositol (PI) 3-kinase/Akt pathway mediates insulin and IGF-1 action. Impaired β-cell expansion is a risk factor for type 2 diabetes. Here, we identified SH2B1, which is highly expressed in β-cells, as a novel regulator of β-cell expansion. Silencing of SH2B1 in INS-1 832/13 β-cells attenuated insulin- and IGF-1-stimulated activation of the PI 3-kinase/Akt pathway and increased streptozotocin (STZ)-induced apoptosis; conversely, overexpression of SH2B1 had the opposite effects. Activation of the PI 3-kinase/Akt pathway in β-cells was impaired in pancreas-specific SH2B1 knockout (PKO) mice fed a high-fat diet (HFD). HFD-fed PKO mice also had increased β-cell apoptosis, decreased β-cell proliferation, decreased β-cell mass, decreased pancreatic insulin content, impaired insulin secretion, and exacerbated glucose intolerance. Furthermore, PKO mice were more susceptible to STZ-induced β-cell destruction, insulin deficiency, and hyperglycemia. These data indicate that SH2B1 in β-cells is an important prosurvival and proproliferative protein and promotes compensatory β-cell expansion in the insulin-resistant state and in response to β-cell stress.
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Affiliation(s)
- Zheng Chen
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI
| | - David L. Morris
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI
| | - Lin Jiang
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI
| | - Yong Liu
- Key Laboratory of Nutrition and Metabolism, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Liangyou Rui
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI
- Corresponding author: Liangyou Rui,
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24
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Shih CH, Chen CJ, Chen L. New function of the adaptor protein SH2B1 in brain-derived neurotrophic factor-induced neurite outgrowth. PLoS One 2013; 8:e79619. [PMID: 24260264 PMCID: PMC3829828 DOI: 10.1371/journal.pone.0079619] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2013] [Accepted: 10/03/2013] [Indexed: 12/12/2022] Open
Abstract
Neurite outgrowth is an essential process for the establishment of the nervous system. Brain-derived neurotrophic factor (BDNF) binds to its receptor TrkB and regulates axonal and dendritic morphology of neurons through signal transduction and gene expression. SH2B1 is a signaling adaptor protein that regulates cellular signaling in various physiological processes. The purpose of this study is to investigate the role of SH2B1 in the development of the central nervous system. In this study, we show that knocking down SH2B1 reduces neurite formation of cortical neurons whereas overexpression of SH2B1β promotes the development of hippocampal neurons. We further demonstrate that SH2B1β promotes BDNF-induced neurite outgrowth and signaling using the established PC12 cells stably expressing TrkB, SH2B1β or SH2B1β mutants. Our data indicate that overexpressing SH2B1β enhances BDNF-induced MEK-ERK1/2, and PI3K-AKT signaling pathways. Inhibition of MEK-ERK1/2 and PI3K-AKT pathways by specific inhibitors suggest that these two pathways are required for SH2B1β-promoted BDNF-induced neurite outgrowth. Moreover, SH2B1β enhances BDNF-stimulated phosphorylation of signal transducer and activator of transcription 3 at serine 727. Finally, our data indicate that the SH2 domain and tyrosine phosphorylation of SH2B1β contribute to BDNF-induced signaling pathways and neurite outgrowth. Taken together, these findings demonstrate that SH2B1β promotes BDNF-induced neurite outgrowth through enhancing pathways involved MEK-ERK1/2 and PI3K-AKT.
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Affiliation(s)
- Chien-Hung Shih
- Institute of Molecular Medicine, National Tsing Hua University, Hsinchu, Taiwan, Republic of China
| | - Chien-Jen Chen
- Institute of Molecular Medicine, National Tsing Hua University, Hsinchu, Taiwan, Republic of China
| | - Linyi Chen
- Institute of Molecular Medicine, National Tsing Hua University, Hsinchu, Taiwan, Republic of China
- Department of Medical Science, National Tsing Hua University, Hsinchu, Taiwan, Republic of China
- * E-mail:
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San-Cristobal R, Milagro FI, Martínez JA. Future Challenges and Present Ethical Considerations in the Use of Personalized Nutrition Based on Genetic Advice. J Acad Nutr Diet 2013; 113:1447-1454. [DOI: 10.1016/j.jand.2013.05.028] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2013] [Accepted: 05/23/2013] [Indexed: 01/06/2023]
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26
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Speakman JR. Functional analysis of seven genes linked to body mass index and adiposity by genome-wide association studies: a review. Hum Hered 2013; 75:57-79. [PMID: 24081222 DOI: 10.1159/000353585] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Genome-wide association studies (GWAS) have identified a total of about 40 single nucleotide polymorphisms (SNPs) that show significant linkage to body mass index, a widely utilised surrogate measure of adiposity. However, only 8 of these associations have been confirmed by follow-up GWAS using more sophisticated measures of adiposity (computed tomography). Among these 8, there is a SNP close to the gene FTO which has been the subject of considerable work to diagnose its function. The remaining 7 SNPs are adjacent to, or within, the genes NEGR1, TMEM18, ETV5, FLJ35779, LINGO2, SH2B1 and GIPR, most of which are less well studied than FTO, particularly in the context of obesity. This article reviews the available data on the functions of these genes, including information gleaned from studies in humans and animal models. At present, we have virtually no information on the putative mechanism associating the genes FLJ35779 and LINGO2 to obesity. All of these genes are expressed in the brain, and for 2 of them (SH2B1 and GIPR), a direct link to the appetite regulation system is known. SH2B1 is an enhancer of intracellular signalling in the JAK-STAT pathway, and GIPR is the receptor for an appetite-linked hormone (GIP) produced by the alimentary tract. NEGR1, ETV5 and SH2B1 all have suggested roles in neurite outgrowth, and hence SNPs adjacent to these genes may affect development of the energy balance circuitry. Although the genes have central patterns of gene expression, implying a central neuronal connection to energy balance, for at least 4 of them (NEGR1, TMEM18, SH2B1 and GIPR), there are also significant peripheral functions related to adipose tissue biology. These functions may contribute to their effects on the obese phenotype.
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Affiliation(s)
- John R Speakman
- Key State Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, PR China; Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen, UK
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