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Urces. Therefore, we entertained the hypothesis that either limited or chronic low-level exposures to nitrosamines account for the observed shifts in morbidity and mortality from insulin resistance diseases. Moreover, given the clear role of high dietary fat intake as a mediator of obesity, T2DM, or cognitive impairment, we proposed that the combined effects of HFD and NDEA exposure may act additi
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P. Chronic HFD feeding aloneTable 3 Effects of High Fat Diet and NDEA Exposure on Biomarkers of Insulin and IGF Resistance in the CerebellummRNA AbPP Tau AChE ChAT Insulin IGF-1 IGF-2 Insulin R IGF-1R IGF-2R IRS-1 IRS-2 IRS-4 LFD+VEH 7.007 ?0.828 12.230 ?1.098 2.829 ?0.178 0.701 ?0.045 0.754 ?0.048 0.957 ?0.119 12.000 ?1.800 17.090 ?1.547 5.031 ?0.525 5.677 ?0.548 5.559 ?0.411 7.701 ?0.509 0.135 ?
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Xidative stress and neurodegeneration. Cerebellar protein homogenates were used to measure (A) GSK-3b; (B) phospho (p)-GSK-3b; (C) GFAP; (D) GAPDH; (E) HNE; (F) malondialdehyde, MDA; (G) Nitrotyrosine, N-TYR; or (H) b-Actin; by direct binding ELISA. Immunoreactivity was detected with HRP-conjugated secondary antibody and Amplex Red soluble fluorophor. Fluorescence light units (FLU) were measured (
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Ry. Early limited exposure to NDEA had no significant effect on any of the indices measured relative to control. Chronic HFD feeding significantly increased the mean levels of pGSK-3b, GFAP, and N-Tyr relative to all other groups (P
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S such as diabetes mellitus [74], chronicTong et al. BMC Endocrine Disorders 2010, 10:4 http://www.biomedcentral.com/1472-6823/10/Page 3 ofalcoholism [75], or obesity with metabolic syndrome [45,46]. These systemic diseases share in common with primary central nervous system (CNS) degenerative diseases, impairments in cognition, and deficits in insulin and IGF signaling mechanisms, insulin/IGF res
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In brain [85-88]; 2) cause cytotoxicity and insulin resistance [83,88]; and 3) are increased in brains with neurodegeneration [85,89-91]. We measured mRNA levels of ceramide synthases (CER), UDP glucose ceramide glycosyltransferase (UGCG), serine palmitoyltransferase (SPTLC), and sphingomyelin phosphodiesterases (SMPD), due to their demonstrated relevance to neurodegeneration [45,83]. HFD feeding
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N exist inTable 2 High Fat Diet Feeding and NDEA Treatment Cause Type 2 Diabetes MellitusAssay Body Wt (g) Glucose (mg/dL) Insulin (ng/ml) Leptin Adiponectin Triglyceride (mg/ml) Free Fatty Acids (mM/mg prot) Cholesterol (mg/ml) LFD+VEH 265.100 ?14.050 111.5 ?1.66 0.0611 ?0.017 4.649 ?0.789 20864 ?1454 0.399 ?0.028 0.150 ?0.003 0.943 ?0.024 LFD+NDEA 266.600 ?19.970 128.8* ?4.31 0.163* ?0.038 4.775
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Lyclonal and monoclonal antibodies and immunodetection reagents were purchased from Abcam (Cambridge, MA), Vector Laboratories (Burlingame, CA), Upstate (Billerica, MA), Chemicon (Temecula, CA), or Molecular Probes (Eugene, OR). The insulin ultra-sensitive ELISA kit was obtained from ALPCO Diagnostics (Salem, NH). Histochoice fixative was purchased from Amresco, Inc (Solon, OH). Antibodies to tumo