Publications by authors named "Christopher S Krumm"

Activation of thermogenic brown adipose tissue (BAT) and inducible beige adipose tissue (BeAT) is triggered by environmental or metabolic stimuli, including cold ambient temperatures and nutrient stress. Thioesterase superfamily member 1 (Them1), a long-chain fatty acyl-CoA thioesterase that is enriched in BAT, suppresses acute cold-induced thermogenesis. Here, we demonstrate that expression was induced in BAT and BeAT by the carbohydrate response element binding protein (ChREBP) in response to chronic cold exposure or to the activation of the integrated stress response (ISR) by nutrient excess.

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Article Synopsis
  • Them1 is an enzyme that regulates fatty acid oxidation and glucose production, particularly in thermogenic adipose tissue and the liver, and is a potential target for treating non-alcoholic fatty liver disease (NAFLD).
  • Researchers screened for small molecule inhibitors that specifically target Them1's activity and identified two effective allosteric inhibitors that bind to its START domain.
  • These inhibitors not only increased fatty acid oxidation in mouse cells but also decreased glucose production, making Them1 a promising avenue for pharmacological intervention in NAFLD.
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Cyclic AMP-responsive element-binding protein H (CREBH encoded by Creb3l3) is a transcription factor that regulates the expression of genes that control lipid and glucose metabolism as well as inflammation. CREBH is upregulated in the liver under conditions of overnutrition, and mice globally lacking the gene (CREBH) are highly susceptible to diet-induced obesity, insulin resistance, and hepatic steatosis. The net protective effects of CREBH have been attributed in large part to the activities of fibroblast growth factor (Fgf)-21 (Fgf21), a target gene that promotes weight loss, improves glucose homeostasis, and reduces hepatic lipid accumulation.

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Aflatoxin B (AFB) widely contaminates staple food and feed crops and is well-known as the most potent natural hepatocarcinogen in humans and domesticated animals. This review highlights significant advances in our understanding of the pivotal role of phase I and II metabolizing enzymes in the bioactivation and detoxification of AFB and its metabolites across species. In humans, cytochrome P450 (CYP) 1A2, CYP3A4, CYP3A5, and CYP3A7 in liver and CYP2A13 in lung are essential for the bioactivation of AFB to the extremely toxic exo-AFB-8,9-epoxide (AFBO), whereas CYP1A1, CYP1A2, CYP2A6, and CYP3A4 are important in the turkey and duck, CYP1A1 and CYP2A6 are important in the chicken and quail, CYP3A11 and CYP3A13 are important in mice, and CYP2A5 are important in the hamster.

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Modern dairy cows meet the energy demand of early lactation by calling on hormonally driven mechanisms to increase the use of lipid reserves. In this context, we recently reported that fibroblast growth factor-21 (FGF21), a hormone required for efficient use of lipid reserves in rodents, is upregulated in periparturient dairy cows. Increased plasma FGF21 in early lactation coincides with elevated circulating concentrations of glucagon (GCG) and nonesterified fatty acids (NEFA).

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This study was designed to establish if Curcumin (CM) alleviates Aflatoxin B₁ (AFB₁)-induced hepatotoxic effects and to determine whether alteration of the expression of cytochrome P450 (CYP450) isozymes is involved in the regulation of these effects in chick liver. One-day-old male broilers ( = 120) were divided into four groups and used in a two by two factorial trial in which the main factors included supplementing AFB₁ (< 5 vs. 100 μg/kg) and CM (0 vs.

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Mammals meet the increased nutritional demands of lactation through a combination of increased feed intake and a collection of adaptations known as adaptive metabolism (e.g., glucose sparing via insulin resistance, mobilization of endogenous reserves, and increased metabolic efficiency via reduced thyroid hormones).

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This study was conducted to determine the effects of aflatoxin B1 (AFB1) on the hepatic transcriptome in ducklings through RNA-sequencing (RNA-Seq). Twenty four, 1-day-old ducklings were divided into 4 treatment groups. Each group received an oral dose of AFB1 at 0, 10, 20, 40 μg/kg BW per day for 2 weeks.

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Cells composing the mammary secretory compartment have evolved a high capacity to secrete not only proteins but also triglycerides and carbohydrates. This feature is illustrated by the mouse, which can secrete nearly twice its own weight in milk proteins, triglycerides and lactose over a short 20-day lactation. The coordination of synthesis and export of products in other secretory cells is orchestrated in part by the transcription factor X-box binding protein 1 (XBP1).

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Two experiments were conducted to screen microorganisms with aflatoxin B1 (AFB1 ) removal potential from soils and to evaluate their ability in reducing the toxic effects of AFB1 in ducklings. In experiment 1, we screened 11 isolates that showed the AFB1 biodegradation ability, and the one exhibited the highest AFB1 removal ability (97%) was characterized and identified as Cellulosimicrobium funkei (C. funkei).

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This study was performed to determine the individual and combined cytotoxic effects of Aflatoxin B1 (AFB1), zearalenone (ZEA), deoxynivalenol (DON) and fumonisin B1 (FB1) on BRL 3A rat liver cells. After the mycotoxins treated the BRL 3A cells for 12, 24 and 48 h, cell viability was determined using the MTT assay. The cytotoxicity of individual mycotoxins on BRL 3A cell viability in decreasing order were DON > AFB1 > ZEA > FB1.

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This study was performed to assess the individual and combined toxic effects of aflatoxin B1 (AFB1), zearalenone (ZEA) and deoxynivalenol (DON) within the liver of mice. A total of 56 4-week-old weanling female mice were divided into seven groups (n = 8). For 2 weeks, each group received an oral administration of either solvent (control), AFB1, ZEA, DON, AFB1 + ZEA, AFB1 + DON or ZEA + DON per day.

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Tin (Sn) is widely used in daily life and distributed in many tissues and nutrients. Although over-ingestion of Sn can cause health problems, relatively little attention has been given to the toxic effects of Sn in livestock health and productivity. This study was performed to investigate the toxic effects of prolonged high intake of dietary Sn on broilers.

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Mammary epithelial cell (MEC) number is an important determinant of milk production in lactating dairy cows. IGF-I increases IGF binding protein-3 (IGFBP-3) production in these cells, which plays a role in its ability to enhance proliferation. In the present study, we show that the apoptotic factor anisomycin (ANS) also increases IGFBP-3 mRNA and protein in a dose- and concentration-dependent manner that mirrors activation of caspase-3 and -7, with significant increases in both IGFBP-3 protein and caspase activation observed by 3 h.

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