Open AccessThe Effect of SH2B1 Variants on Expression of Leptin- and Insulin-Induced Pathways in Murine Hypothalamus
Author(s) -
Giuranna Johanna,
Volckmar Anna-Lena,
Heinen Anna,
Peters Triinu,
Schmidt Börge,
Spieker Anne,
Straub Helena,
Grallert Harald,
Müller Timo D.,
Antel Jochen,
Haußmann Ute,
Klafki Hans,
Rui Liangyou,
Hebebrand Johannes,
Hinney Anke
Publication year - 2018
Publication title -
obesity facts
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.398
H-Index - 45
eISSN - 1662-4033
pISSN - 1662-4025
DOI - 10.1159/000486962
Subject(s) - research article
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.