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Pyruvate dehydrogenase kinase

About: Pyruvate dehydrogenase kinase is a research topic. Over the lifetime, 4224 publications have been published within this topic receiving 161052 citations. The topic is also known as: [pyruvate dehydrogenase (lipoamide)] kinase & pyruvate dehydrogenase (lipoamide) kinase.


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Journal ArticleDOI
21 May 2015-Oncogene
TL;DR: In this article, the authors found that metabolic stress is one of the mechanisms that elevate MACC1 expression in colon cancer cells and that upregulation compensatively ensures GC growth against metabolic stress by facilitating the Warburg effect.
Abstract: Cancer cells mainly metabolize by glycolysis (the Warburg effect) and are better adapted to resist metabolic stress. Metastasis-associated in colon cancer-1 (MACC1) is an oncogene promoting gastric cancer (GC) growth and metastasis, and its expression positively correlates with GC progression. However, it is unknown why MACC1 elevates with GC progression and what is its role in cancer metabolism. In this study, we discovered that MACC1 expression was significantly upregulated via adenosine monophosphate-activated protein kinase signaling in response to glucose deprivation-induced metabolic stress. Clinical observation demonstrates that MACC1 expression was higher in advanced stage GC. MACC1 expression was proved to be positively correlated with the maximum standardized uptake value of (18)F-deoxyglucose in the patients, and MACC1 enhanced (18)F-deoxyglucose uptake in GC cells and the xenografts. The underlying mechanism was that MACC1 promoted the Warburg effect by upregulating the activities and expressions of a series of glycolytic enzymes, including hexokinase, pyruvate dehydrogenase kinase and lactate dehydrogenase, in GC cells. This metabolic shift enhanced cell viability and resistance to apoptosis by facilitating ATP generation, reducing the reactive oxygen species production and stabilizing the mitochondrial membrane potential. In contrast, MACC1-silenced or the Warburg effect-blocked GC cells were more vulnerable to metabolic stress. In conclusion, metabolic stress is one of the mechanisms that elevate MACC1 expression in GC, and MACC1 upregulation compensatively ensures GC growth against metabolic stress by facilitating the Warburg effect.

66 citations

Journal ArticleDOI
TL;DR: Findings indicate that pyruvate can protect cellular glutathione, thus enhancing cellular antioxidant potential, and that enhanced antioxidant potential can desensitize NF-kappaB transactivation due to reactive oxygen species, suggesting possible metabolic redox relations to NF- kappaB.
Abstract: We recently reported that pyruvate inhibited translocation and activation of p53 caused by DNA damage due to oxidant injury (Lee YJ, Kang IJ, Bunger R, and Kang YH. Microvasc Res 66: 91-101, 2003);...

66 citations

Journal ArticleDOI
TL;DR: Small electron-withdrawing groups on the ortho position of the anilide increased potency 20-40-fold and could be of utility to ameliorate conditions of inappropriate blood lactate elevation.
Abstract: The optimization of a series of anilide derivatives of (R)-3,3,3-trifluoro-2-hydroxy-2-methylpropionic acid as inhibitors of pyruvate dehydrogenase kinase (PDHK) is described that started from N-phenyl-3,3,3-trifluoro-2-hydroxy-2-methylpropanamide 1 (IC50 = 35 ± 1.4 μM). It was found that small electron-withdrawing groups on the ortho position of the anilide, i.e., chloro, acetyl, or bromo, increased potency 20−40-fold. The oral bioavailability of the compounds in this series is optimal (as measured by AUC) when the anilide is substituted at the 4-position with an electron-withdrawing group (i.e., carboxyl, carboxyamide, and sulfoxyamide). N-(2-Chloro-4-isobutylsulfamoylphenyl)-(R)-3,3,3-trifluoro-2-hydroxy-2-methylpropionamide (10a) inhibits PDHK in the primary enzymatic assay with an IC50 of 13 ± 1.5 nM, enhances the oxidation of [14C]lactate into 14CO2 in human fibroblasts, lowers blood lactate levels significantly 2.5 and 5 h after oral doses as low as 30 μmol/kg, and increases the ex vivo activity of...

66 citations

Journal ArticleDOI
TL;DR: Findings indicate inhibition of PDK4 may potentiate cisplatin-induced cell death and warrant further studies investigating the mechanism through which this occurs.
Abstract: Advanced bladder cancer (BCa) remains a major source of mortality, with poor treatment options. Cisplatin based chemotherapy is the standard treatment, however many patients are or become resistant. One potential cause of chemoresistance is the Warburg Effect, a metabolic switch to aerobic glycolysis that occurs in many cancers. Upregulation of the pyruvate dehydrogenase kinase family (PDK1-4) is associated with aerobic glycolysis and chemoresistance through inhibition of the pyruvate dehydrogenase complex (PDH). We have previously observed upregulation of PDK4 in high grade compared to low grade bladder cancers. We initiated this study to determine if inhibition of PDK4 could reduce tumor growth rates or sensitize BCa cells to cisplatin. Upregulation of PDK4 in malignant BCa cell lines as compared to benign transformed urothelial cells was confirmed using qPCR. Inhibition of PDK4 with dichloroacetate (DCA) resulted in increased PDH activity, reduced cell growth, and G0/G1 phase arrest in BCa cells. Similarly, siRNA knockdown of PDK4 inhibited BCa cell proliferation. Co-treatment of BCa cells with cisplatin and DCA did not increase caspase-3 activity but did enhance overall cell death in vitro. While daily treatment with 200mg/kg DCA alone did not reduce tumor volumes in a xenograft model, combination treatment with cisplatin resulted in dramatically reduced tumor volumes as compared to either DCA or cisplatin alone. This was attributed to substantial intra-tumoral necrosis. These findings indicate inhibition of PDK4 may potentiate cisplatin induced cell death and warrant further studies investigating the mechanism through which this occurs.

66 citations

Journal ArticleDOI
TL;DR: The findings suggest that aerobically trained human skeletal muscle has an increased maximal capacity to utilize carbohydrates, evident by increased PDHt, but increased metabolic control sensitivity to pyruvate through increased contribution of PDK2 to total PDK activity.
Abstract: This study examined the effects of short- and long-term aerobic training on the stable up-regulation of pyruvate dehydrogenase (PDH) and PDH kinase (PDK) in human skeletal muscle. We hypothesized that 8 weeks, but not 1 week, of aerobic training would increase total PDH (PDHt) and PDK activities compared to pretraining, and this would be detectable at the level of gene transcription (mRNA) and/or gene translation (protein). Resting muscle biopsies were taken before and after 1 and 8 weeks of aerobic cycle exercise training. PDHt and PDK activities, and their respective protein and mRNA expression, did not differ after 1 week of aerobic training. PDHt activity increased 31% after 8 weeks and this may be partially due to a 1.3-fold increase in PDH-E(1)alpha protein expression. PDK activity approximately doubled after 8 weeks of aerobic training and this was attributed to a 1.3-fold increase in PDK2 isoform protein expression. Similar to 1 week, no changes were observed at the mRNA level after 8 weeks of training. These findings suggest that aerobically trained human skeletal muscle has an increased maximal capacity to utilize carbohydrates, evident by increased PDHt, but increased metabolic control sensitivity to pyruvate through increased contribution of PDK2 to total PDK activity.

66 citations


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Performance
Metrics
No. of papers in the topic in previous years
YearPapers
202329
202234
202161
202063
201959
201851