Various cytokines have been implicated in cancer cachexia. One such cytokine is IL-6, deemed as a key cachectic factor in mice inoculated with colon carcinoma 26 (C26) cells, a widely used cancer cachexia model. Here we tested the causal role of IL-6 in cancer cachexia by knocking out the IL-6 gene in C26 cells.
View Article and Find Full Text PDFThe bacterial determinants that facilitate Mycobacterium tuberculosis (Mtb) adaptation to the human host environment are poorly characterized. We have sought to decipher the pressures facing the bacterium in vivo by assessing Mtb genes that are under positive selection in clinical isolates. One of the strongest targets of selection in the Mtb genome is lldD2, which encodes a quinone-dependent L-lactate dehydrogenase (LldD2) that catalyzes the oxidation of lactate to pyruvate.
View Article and Find Full Text PDFUnlabelled: Mammalian tissues feed on nutrients in the blood circulation. At the organism-level, mammalian energy metabolism comprises of oxidation, storage, interconverting, and releasing of circulating nutrients. Though much is known about the individual processes and nutrients, a holistic and quantitative model describing these processes for all major circulating nutrients is lacking.
View Article and Find Full Text PDFThe role of glutathione peroxidase 4 (GPX4) in ferroptosis and various cancers is well-established; however, its specific contribution to colorectal cancer has been unclear. Surprisingly, in a genetic mouse model of colon tumors, the deletion of GPX4 specifically in colon epithelial cells increased tumor burden but decreased oxidized glutathione. Notably, this specific GPX4 deletion did not enhance susceptibility to dextran sodium sulfate (DSS)-induced colitis in mice with varied iron diets but showed vulnerability in mice with a vitamin E-deficient diet.
View Article and Find Full Text PDFThe bacterial determinants that facilitate (Mtb) adaptation to the human host environment are poorly characterized. We have sought to decipher the pressures facing the bacterium by assessing Mtb genes that are under positive selection in clinical isolates. One of the strongest targets of selection in the Mtb genome is , which encodes a quinone-dependent L-lactate dehydrogenase (LldD2) that catalyzes the oxidation of lactate to pyruvate.
View Article and Find Full Text PDFVarious cytokines have been implicated in cancer cachexia. One such cytokine is IL-6, which has been deemed a key cachectic factor in mice inoculated with the colon carcinoma 26 (C26) cells, one of the most widely used models of cancer cachexia. Here to test the causal role of IL-6 in cancer cachexia, we used CRISPR/Cas9 editing to knock out in C26 cells.
View Article and Find Full Text PDFSenescent cells exhibit a reduced response to intrinsic and extrinsic stimuli. This diminished reaction may be explained by the disrupted transmission of nuclear signals. However, this hypothesis requires more evidence before it can be accepted as a mechanism of cellular senescence.
View Article and Find Full Text PDFJ Gerontol A Biol Sci Med Sci
July 2020
Budding yeast generate heterogeneous cells that can be separated into two distinctive cell types: short-living low-density and long-living high-density (HD) cells by density gradient centrifugation. We found that ethanol and acetate induce formation of HD cells, and mitochondrial respiration is required. From their transcriptomes and metabolomes, we found upregulated differentially expressed genes in HD cells involved in the RGT2/RGT1 glucose sensing pathway and its downstream genes encoding hexose transporters.
View Article and Find Full Text PDFCaloric restriction (CR) has been shown to extend lifespan and prevent cellular senescence in various species ranging from yeast to humans. Many effects of CR may contribute to extend lifespan. Specifically, CR prevents oxidative damage from reactive oxygen species (ROS) by enhancing mitochondrial function.
View Article and Find Full Text PDFDown-regulation of intracellular nutrient signal pathways was proposed to be a primary mechanism of caloric restriction (CR)-mediated lifespan extension. However, the link between lifespan and glucose sensors in the plasma membrane was poorly understood in yeast. Herein, a mutant that lacked glucose sensors (snf3Δrgt2Δ) had impaired glucose fermentation, showed decreased chronological lifespan (CLS), and reduced CLS extension by CR.
View Article and Find Full Text PDFCaloric restriction mimetics (CRMs) have been developed to mimic the effects of caloric restriction (CR). However, research reports for the effects of CRMs are often times inconsistent across different research groups. Therefore, in this study, we compared seven identified CRMs which extend the lifespans of various organisms including caffeine, curcumin, dapsone, metformin, rapamycin, resveratrol, and spermidine to CR for mitochondrial function in a single model, Saccharomyces cerevisiae.
View Article and Find Full Text PDFActivation of Janus kinases (JAKs) and Signal Transducers and Activators of Transcription (STATs) plays a crucial role in cell survival and proliferation. The JAK/STAT signaling pathway has received a great deal of attention as a therapeutic target for the treatment of cancer. Thus, the identification of a compound that blocks this pathway would contribute significantly to growth inhibition and apoptosis of tumor cells.
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