ABSTRACT
En1, Nr2f1, Gpc4, Sfrp2, Shox2, Tbx15 and Thbd are among the genes involved in development process of an organism in a number of tissues, in particular adipose tissue. Considering the involvement of isobutyl-methyl-xanthine (IBMX), indomethacin, dexamethasone (DEX), triiodothyronine (T3), and insulin in adipocyte differentiation, we propose that these differentiation-inducing agents may regulate differentiation in brown adipose tissue through a developmental process. Stromavascular cells isolated from interscapular brown fat of mice were cultured in DMEM-LG medium. Proliferating brown preadipocytes were differentiated in the presence of IBMX, indomethacin, DEX, T3 and insulin. Pref1 (marker of proliferation stage) and uncoupling protein 1 (UCP1, marker for differentiation stage) were upregulated during proliferation and differentiation, respectively. Relative expression of Pref1, UCP1 and developmental genes was determined in different stages of adipogenesis. En1, Gpc4, Nr2f1, Sfrp2 and Shox2 were upregulated during differentiation. Differentiation of preadipocytes in the absence of IBMX, indomethacin, and DEX resulted in drastic reduction in fat accumulation in differentiated adipocytes with simultaneous decrease in En1, Gpc4, Nr2f1, Sfrp2, Shox2 and Tbx15 gene expression. T3 upregulated the expression of En1, Gpc4, Sfrp2 and Tbx15 genes during differentiation and downregulated Shox2 expression as compared to proliferated state. Insulin upregulated the expression of Shox2.
Subject(s)
Adipocytes, Brown/cytology , Adipogenesis/physiology , Adipose Tissue, Brown/cytology , Cell Differentiation/physiology , Gene Expression/physiology , 1-Methyl-3-isobutylxanthine/pharmacology , Adipocytes, Brown/metabolism , Adipogenesis/drug effects , Adipose Tissue, Brown/drug effects , Animals , Cell Differentiation/drug effects , Cell Proliferation , Cells, Cultured , Dexamethasone/pharmacology , Gene Expression/drug effects , Genes, Developmental/drug effects , Genes, Developmental/genetics , Indomethacin/pharmacology , Insulin/pharmacology , Lipid Metabolism , Lipids , Male , Mice , Triiodothyronine/pharmacologyABSTRACT
To identify risk factors for scrub typhus in Darjeeling, India, we compared 62 scrub typhus cases (acute fever with eschar and specific IgM) with 62 neighbourhood controls. Cases were more likely to live close to bushes [matched odds ratio (MOR) 10; 95% CI 2.3-63] and wood piles (MOR 3.5; 95% CI 1.5-9.5), to work on farms (MOR 10; 95% CI 2.7-63), to observe rodents at home (MOR 3.6; 95% CI 1.4-11) and at work (MOR 9; 95% CI 2.4-57), and to rear domestic animals (MOR 2.4; 95% CI 1.1-5.7). Cases were less likely to wash after work (MOR 0.4; 95% CI 0.1-0.9) and change clothes to sleep (MOR 0.2; 95% CI 0.1-0.5). A cleaner, rodent-controlled environment may prevent exposure to scrub typhus. Personal protection measures and better hygiene could further reduce individual risk.
