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Keywords = pyruvate dehydrogenase kinase 4 (PDK4)

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14 pages, 5130 KiB  
Article
Sodium Phenylbutyrate Attenuates Cisplatin-Induced Acute Kidney Injury Through Inhibition of Pyruvate Dehydrogenase Kinase 4
by Chang Joo Oh, Wooyoung Choi, Ha Young Lee, In-Kyu Lee, Min-Ji Kim and Jae-Han Jeon
Biomedicines 2024, 12(12), 2815; https://doi.org/10.3390/biomedicines12122815 - 11 Dec 2024
Viewed by 1357
Abstract
Background/Objectives: Cisplatin nephrotoxicity is a significant clinical issue, and currently, no approved drug exists to prevent cisplatin-induced acute kidney injury (AKI). This study investigated whether sodium phenylbutyrate (4-PBA), a chemical chaperone, can prevent cisplatin-induced AKI. Methods: Six consecutive days of intraperitoneal injections of [...] Read more.
Background/Objectives: Cisplatin nephrotoxicity is a significant clinical issue, and currently, no approved drug exists to prevent cisplatin-induced acute kidney injury (AKI). This study investigated whether sodium phenylbutyrate (4-PBA), a chemical chaperone, can prevent cisplatin-induced AKI. Methods: Six consecutive days of intraperitoneal injections of 4-PBA were administered in a murine model before and after the cisplatin challenge. This study evaluated tubular injury, serum blood urea nitrogen (BUN) and creatinine levels, and inflammatory markers such as tumor necrosis factor-alpha (TNF-α) and intercellular adhesion molecule 1 (ICAM-1). Additionally, apoptosis, mitochondrial membrane potential, oxygen consumption ratio, and reactive oxygen species (ROS) were assessed in renal tubular cells. The expression levels of pyruvate dehydrogenase kinase 4 (Pdk4) were also analyzed. Results: 4-PBA prevented tubular injury and normalized serum BUN and creatinine levels. Inflammatory markers TNF-α and ICAM-1 were suppressed. In renal tubular cells, 4-PBA reduced apoptosis, restored mitochondrial membrane potential and oxygen consumption ratio, and reduced ROS production. Mechanistically, 4-PBA suppressed the expression of Pdk4, which is known to be induced during cisplatin-induced renal injury. The protective effect of 4-PBA was abolished in Pdk4-overexpressing renal tubular cells, indicating that the efficacy of 4-PBA partially depends on the suppression of Pdk4 expression. In cancer cells, 4-PBA did not interfere with the anti-cancer efficacy of cisplatin. Conclusions: These findings suggest that 4-PBA effectively prevents cisplatin-induced acute kidney injury by suppressing Pdk4. Full article
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12 pages, 2286 KiB  
Article
Genetic Ablation of Pyruvate Dehydrogenase Kinase Isoform 4 Gene Enhances Recovery from Hyperoxic Lung Injury: Insights into Antioxidant and Inflammatory Mechanisms
by Keisuke Watanabe, Akie Kato, Hiroyuki Adachi, Atsuko Noguchi, Hirokazu Arai, Masato Ito, Fumihiko Namba and Tsutomu Takahashi
Biomedicines 2024, 12(4), 746; https://doi.org/10.3390/biomedicines12040746 - 27 Mar 2024
Viewed by 1798
Abstract
Background: Pyruvate dehydrogenase kinase isoform 4 (PDK4) plays a pivotal role in the regulation of cellular proliferation and apoptosis. The objective of this study was to examine whether the genetic depletion of the PDK4 gene attenuates hyperoxia-induced lung injury in neonatal mice. Methods: [...] Read more.
Background: Pyruvate dehydrogenase kinase isoform 4 (PDK4) plays a pivotal role in the regulation of cellular proliferation and apoptosis. The objective of this study was to examine whether the genetic depletion of the PDK4 gene attenuates hyperoxia-induced lung injury in neonatal mice. Methods: Neonatal PDK4−/− mice and wild-type (WT) mice were exposed to oxygen concentrations of 21% (normoxia) and 95% (hyperoxia) for the first 4 days of life. Pulmonary histological assessments were performed, and the mRNA levels of lung PDK4, monocyte chemoattractant protein (MCP)-1 and interleukin (IL)-6 were assessed. The levels of inflammatory cytokines in lung tissue were quantified. Results: Following convalescence from neonatal hyperoxia, PDK4−/− mice exhibited improved lung alveolarization. Notably, PDK4−/− mice displayed significantly elevated MCP-1 protein levels in pulmonary tissues following 4 days of hyperoxic exposure, whereas WT mice showed increased IL-6 protein levels under similar conditions. Furthermore, neonatal PDK4−/− mice subjected to hyperoxia demonstrated markedly higher MCP-1 mRNA expression at 4 days of age compared to WT mice, while IL-6 mRNA expression remained unaffected in PDK4−/− mice. Conclusions: Newborn PDK4−/− mice exhibited notable recovery from hyperoxia-induced lung injury, suggesting the potential protective role of PDK4 depletion in mitigating lung damage. Full article
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21 pages, 12584 KiB  
Article
Circadian Rhythm Alteration of the Core Clock Genes and the Lipid Metabolism Genes Induced by High-Fat Diet (HFD) in the Liver Tissue of the Chinese Soft-Shelled Turtle (Trionyx sinensis)
by Li Liu, Lingli Liu, Shiming Deng, Li Zou, Yong He, Xin Zhu, Honghui Li, Yazhou Hu, Wuying Chu and Xiaoqing Wang
Genes 2024, 15(2), 157; https://doi.org/10.3390/genes15020157 - 25 Jan 2024
Cited by 5 | Viewed by 3216
Abstract
Physiology disorders of the liver, as it is an important tissue in lipid metabolism, can cause fatty liver disease. The mechanism might be regulated by 17 circadian clock genes and 18 fat metabolism genes, together with a high-fat diet (HFD). Due to their [...] Read more.
Physiology disorders of the liver, as it is an important tissue in lipid metabolism, can cause fatty liver disease. The mechanism might be regulated by 17 circadian clock genes and 18 fat metabolism genes, together with a high-fat diet (HFD). Due to their rich nutritional and medicinal value, Chinese soft-shelled turtles (Trionyx sinensis) are very popular among the Chinese people. In the study, we aimed to investigate the influence of an HFD on the daily expression of both the core clock genes and the lipid metabolism genes in the liver tissue of the turtles. The two diets were formulated with 7.98% lipid (the CON group) and 13.86% lipid (the HFD group) to feed 180 juvenile turtles, which were randomly divided into two groups with three replicates per group and 30 turtles in each replicate for six weeks, and the diet experiment was administrated with a photophase regimen of a 24 h light/dark (12L:12D) cycle. At the end of the experiment, the liver tissue samples were collected from nine turtles per group every 3 h (zeitgeber time: ZT 0, 3, 6, 9, 12, 15, 18, 21 and 24) for 24 h to investigate the daily expression and correlation analysis of these genes. The results showed that 11 core clock genes [i.e., circadian locomotor output cycles kaput (Clock), brain and muscle arnt-like protein 1 and 2 (Bmal1/2), timeless (Tim), cryptochrome 1 (Cry2), period2 (Per2), nuclear factor IL-3 gene (Nfil3), nuclear receptor subfamily 1, treatment D, member 1 and 2 (Nr1d1/2) and retinoic acid related orphan receptor α/β/γ β and γ (Rorβ/γ)] exhibited circadian oscillation, but 6 genes did not, including neuronal PAS domain protein 2 (Npas2), Per1, Cry1, basic helix-loop-helix family, member E40 (Bhlhe40), Rorα and D-binding protein (Dbp), and 16 lipid metabolism genes including fatty acid synthase (Fas), diacylglycerol acyltransferase 1 (Dgat1), 3-hydroxy-3-methylglutaryl-CoA reductase (Hmgcr), Low-density lipoprotein receptor-related protein 1-like (Ldlr1), Lipin 1 (Lipin1), Carnitine palmitoyltransferase 1A (Cpt1a), Peroxisome proliferator activation receptor α, β and γ (Pparα/β/γ), Sirtuin 1 (Sirt1), Apoa (Apoa1), Apolipoprotein B (Apob), Pyruvate Dehydrogenase kinase 4 (Pdk4), Acyl-CoA synthase long-chain1 (Acsl1), Liver X receptors α (Lxrα) and Retinoid X receptor, α (Rxra) also demonstrated circadian oscillations, but 2 genes did not, Scd and Acaca, in the liver tissues of the CON group. However, in the HFD group, the circadian rhythms’ expressional patterns were disrupted for the eight core clock genes, Clock, Cry2, Per2, Nfil3, Nr1d1/2 and Rorβ/γ, and the peak expression of Bmal1/2 and Tim showed delayed or advanced phases. Furthermore, four genes (Cry1, Per1, Dbp and Rorα) displayed no diurnal rhythm in the CON group; instead, significant circadian rhythms appeared in the HFD group. Meanwhile, the HFD disrupted the circadian rhythm expressions of seven fat metabolism genes (Fas, Cpt1a, Sirt1, Apoa1, Apob, Pdk4 and Acsl1). Meanwhile, the other nine genes in the HFD group also showed advanced or delayed expression peaks compared to the CON group. Most importantly of all, there were remarkably positive or negative correlations between the core clock genes and the lipid metabolism genes, and their correlation relationships were altered by the HFD. To sum up, circadian rhythm alterations of the core clock genes and the lipid metabolism genes were induced by the high-fat diet (HFD) in the liver tissues of T. sinensis. This result provides experimental and theoretical data for the mass breeding and production of T. sinensis in our country. Full article
(This article belongs to the Special Issue Fisheries and Aquaculture Gene Expression)
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14 pages, 2410 KiB  
Article
A Potent PDK4 Inhibitor for Treatment of Heart Failure with Reduced Ejection Fraction
by Kenichi Aizawa, Akari Ikeda, Shota Tomida, Koki Hino, Yuuki Sugita, Tomoyasu Hirose, Toshiaki Sunazuka, Hiroshi Kido, Shigeyuki Yokoyama and Ryozo Nagai
Cells 2024, 13(1), 87; https://doi.org/10.3390/cells13010087 - 30 Dec 2023
Cited by 7 | Viewed by 3490
Abstract
Heart failure with reduced ejection fraction (HFrEF) is characterized not only by reduced left ventricular ejection fraction (EF) but is also combined with symptoms such as dyspnea, fatigue, and edema. Several pharmacological interventions have been established. However, a treatment targeting a novel pathophysiological [...] Read more.
Heart failure with reduced ejection fraction (HFrEF) is characterized not only by reduced left ventricular ejection fraction (EF) but is also combined with symptoms such as dyspnea, fatigue, and edema. Several pharmacological interventions have been established. However, a treatment targeting a novel pathophysiological mechanism is still needed. Evidence indicating that inhibition of pyruvate dehydrogenase kinase 4 (PDK4) may be cardioprotective has been accumulating. Thus, we focused on vitamin K3 and used its framework as a new PDK4 inhibitor skeleton to synthesize new PDK4 inhibitors that show higher activity than the existing PDK4 inhibitor, dichloroacetic acid, and tested their cardioprotective effects on a mouse heart failure model. Among these inhibitors, PDK4 inhibitor 8 improved EF the most, even though it did not reverse cardiac fibrosis or wall thickness. This novel, potent PDK4 inhibitor may improve EF of failing hearts by regulating bioenergetics via activation of the tricarboxylic acid cycle. Full article
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15 pages, 2854 KiB  
Article
Human Umbilical Cord Mesenchymal Stem Cells Protect against Renal Ischemia-Reperfusion Injury by Secreting Extracellular Vesicles Loaded with miR-148b-3p That Target Pyruvate Dehydrogenase Kinase 4 to Inhibit Endoplasmic Reticulum Stress at the Reperfusion Stages
by Wei Shi, Xiang Zhou, Xinyuan Li, Xiang Peng, Guo Chen, Yang Li, Chunlin Zhang, Haitao Yu, Zhenwei Feng, Xin Gou and Jing Fan
Int. J. Mol. Sci. 2023, 24(10), 8899; https://doi.org/10.3390/ijms24108899 - 17 May 2023
Cited by 13 | Viewed by 2259
Abstract
Renal ischemia-reperfusion (I/R) injury is a leading cause of acute kidney injury (AKI), with high mortality. Recent studies have reported that human umbilical cord mesenchymal stem cells (HucMSCs) play an important role in repairing organ and tissue injuries because of their unique characteristics. [...] Read more.
Renal ischemia-reperfusion (I/R) injury is a leading cause of acute kidney injury (AKI), with high mortality. Recent studies have reported that human umbilical cord mesenchymal stem cells (HucMSCs) play an important role in repairing organ and tissue injuries because of their unique characteristics. However, the potential of HucMSC extracellular vesicles (HucMSC-EVs) to promote the repair of renal tubular cells remains to be explored. This study found that HucMSC-EVs derived from HucMSCs played a protective role and were associated with kidney I/R injury. We found that miR-148b-3p in HucMSC-EVs had a protective effect against kidney I/R injury. HK-2 cells overexpressing miR-148b-3p were protected against I/R injury by inhibiting apoptosis. Next, the target mRNA of miR-148b-3p was predicted online, and the target mRNA, pyruvate dehydrogenase kinase 4 (PDK4), was identified and verified using dual luciferase. We discovered that I/R injury significantly increased endoplasmic reticulum (ER) stress, whereas siR-PDK4 inhibited these effects and protected against I/R injury. Interestingly, after administrating HucMSC-EVs to HK-2 cells, PDK4 expression and ER stress induced by I/R injury were significantly inhibited. HK-2 ingested miR-148b-3p from HucMSC-EVs, and its ER induced by I/R injury was significantly deregulated. This study suggests that HucMSC-EVs protect kidneys from I/R injury during the early I/R stage. These results suggest a new mechanism for HucMSC-EVs in treating AKI and provide a new treatment strategy for I/R injury. Full article
(This article belongs to the Section Molecular Endocrinology and Metabolism)
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13 pages, 2405 KiB  
Article
Pyruvate Dehydrogenase Kinase 4 Deficiency Increases Tumorigenesis in a Murine Model of Bladder Cancer
by Benjamin L. Woolbright, Ganeshkumar Rajendran, Erika Abbott, Austin Martin, Ryan Didde, Katie Dennis, Robert A. Harris and John A. Taylor
Cancers 2023, 15(6), 1654; https://doi.org/10.3390/cancers15061654 - 8 Mar 2023
Cited by 5 | Viewed by 2378
Abstract
Pyruvate dehydrogenase kinase 4 (PDK4) is a mitochondrial isozyme in the PDK family (PDK1-4) partially responsible for phosphorylation of pyruvate dehydrogenase (PDH). Phosphorylation of PDH is thought to result in a pro-proliferative shift in metabolism that sustains growth of cancer cells. Previous data [...] Read more.
Pyruvate dehydrogenase kinase 4 (PDK4) is a mitochondrial isozyme in the PDK family (PDK1-4) partially responsible for phosphorylation of pyruvate dehydrogenase (PDH). Phosphorylation of PDH is thought to result in a pro-proliferative shift in metabolism that sustains growth of cancer cells. Previous data from our lab indicate the pan-PDK inhibitor dichloroacetate (DCA) or acute genetic knockdown of PDK4 blocks proliferation of bladder cancer (BCa) cells. The goal of this study was to determine the role of PDK4 in an in vivo BCa model, with the hypothesis that genetic depletion of PDK4 would impair formation of BCa. PDK4−/− or WT animals were exposed to N-Butyl-N-(4-hydroxybutyl) nitrosamine (BBN) for 16 weeks, and tumors were allowed to develop for up to 7 additional weeks. PDK4−/− mice had significantly larger tumors at later time points. When animals were treated with cisplatin, PDK4−/− animals still had larger tumors than WT mice. PDK4 expression was assessed in human tissue and in mice. WT mice lost expression of PDK4 as tumors became muscle-invasive. Similar results were observed in human samples, wherein tumors had less expression of PDK4 than benign tissue. In summary, PDK4 has a complex, multifunctional role in BCa and may represent an underrecognized tumor suppressor. Full article
(This article belongs to the Special Issue Targeting Tumor Niches for Cancer Chemoprevention and Treatment)
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28 pages, 7161 KiB  
Article
Interaction between Butyrate and Tumor Necrosis Factor α in Primary Rat Colonocytes
by Christopher L. Souders, Juan J. Aristizabal-Henao, Sarah J. Patuel, John A. Bowden, Jasenka Zubcevic and Christopher J. Martyniuk
Biomolecules 2023, 13(2), 258; https://doi.org/10.3390/biom13020258 - 30 Jan 2023
Cited by 6 | Viewed by 3344
Abstract
Butyrate, a short-chain fatty acid, is utilized by the gut epithelium as energy and it improves the gut epithelial barrier. More recently, it has been associated with beneficial effects on immune and cardiovascular homeostasis. Conversely, tumor necrosis factor alpha (TNFα) is a pro-inflammatory [...] Read more.
Butyrate, a short-chain fatty acid, is utilized by the gut epithelium as energy and it improves the gut epithelial barrier. More recently, it has been associated with beneficial effects on immune and cardiovascular homeostasis. Conversely, tumor necrosis factor alpha (TNFα) is a pro-inflammatory and pro-hypertensive cytokine. While butyrate and TNFα are both linked with hypertension, studies have not yet addressed their interaction in the colon. Here, we investigated the capacity of butyrate to modulate a host of effects of TNFα in primary rodent colonic cells in vitro. We measured ATP levels, cell viability, mitochondrial membrane potential (MMP), reactive oxygen species (ROS), mitochondrial oxidative phosphorylation, and glycolytic activity in colonocytes following exposure to either butyrate or TNFα, or both. To address the potential mechanisms, transcripts related to oxidative stress, cell fate, and cell metabolism (Pdk1, Pdk2, Pdk4, Spr, Slc16a1, Slc16a3, Ppargc1a, Cs, Lgr5, Casp3, Tnfr2, Bax, Bcl2, Sod1, Sod2, and Cat) were measured, and untargeted liquid chromatography–tandem mass spectrometry (LC-MS/MS) was employed to profile the metabolic responses of colonocytes following exposure to butyrate and TNFα. We found that both butyrate and TNFα lowered cellular ATP levels towards a quiescent cell energy phenotype, characterized by decreased oxygen consumption and extracellular acidification. Co-treatment with butyrate ameliorated TNFα-induced cytotoxicity and the reduction in cell viability. Butyrate also opposed the TNFα-mediated decrease in MMP and mitochondrial-to-intracellular calcium ratios, suggesting that butyrate may protect colonocytes against TNFα-induced cytotoxicity by decreasing mitochondrial calcium flux. The relative expression levels of pyruvate dehydrogenase kinase 4 (Pdk4) were increased via co-treatment of butyrate and TNFα, suggesting the synergistic inhibition of glycolysis. TNFα alone reduced the expression of monocarboxylate transporters slc16a1 and slc16a3, suggesting effects of TNFα on butyrate uptake into colonocytes. Of the 185 metabolites that were detected with LC-MS, the TNFα-induced increase in biopterin produced the only significant change, suggesting an alteration in mitochondrial biogenesis in colonocytes. Considering the reports of elevated colonic TNFα and reduced butyrate metabolism in many conditions, including in hypertension, the present work sheds light on cellular interactions between TNFα and butyrate in colonocytes that may be important in understanding conditions of the colon. Full article
(This article belongs to the Section Natural and Bio-derived Molecules)
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15 pages, 874 KiB  
Article
Altered Left Ventricular Rat Gene Expression Induced by the Myosin Activator Omecamtiv Mecarbil
by Bachar El Oumeiri, Laurence Dewachter, Philippe Van de Borne, Géraldine Hubesch, Christian Melot, Pascale Jespers, Constantin Stefanidis, Kathleen Mc Entee and Frédéric Vanden Eynden
Genes 2023, 14(1), 122; https://doi.org/10.3390/genes14010122 - 1 Jan 2023
Cited by 2 | Viewed by 3114
Abstract
To explore the impact of omecamtiv mecarbil (OM) on the gene expression profile in adult male rats. Fourteen male Wistar rats were randomly assigned to a single OM (1.2 mg/kg/h; n = 6) or placebo (n = 8) 30-min infusion. Echocardiography was performed [...] Read more.
To explore the impact of omecamtiv mecarbil (OM) on the gene expression profile in adult male rats. Fourteen male Wistar rats were randomly assigned to a single OM (1.2 mg/kg/h; n = 6) or placebo (n = 8) 30-min infusion. Echocardiography was performed before and after OM infusion. Seven days after infusion, rats were euthanized, and left ventricular (LV) tissues were removed for real-time quantitative polymerase chain reaction (RTq-PCR) experiments. After OM infusion, pro-apoptotic Bax-to-Bcl2 ratio was decreased, with increased Bcl2 and similar Bax gene expression. The gene expression of molecules regulating oxidative stress, including glutathione disulfide reductase (Gsr) and superoxide dismutases (Sod1/Sod2), remained unchanged, whereas the expression of antioxidant glutathione peroxidase (Gpx) increased. While LV gene expression of key energy sensors, peroxisome proliferator activator (Ppar) α and γ, AMP-activated protein kinase (Ampk), and carnitine palmitoyltransferase 1 (Cpt1) remained unchanged after OM infusion, and the expression of pyruvate dehydrogenase kinase 4 (Pdk4) increased. The LV expression of the major myocardial glucose transporter Glut1 decreased, with no changes in Glut4 expression, whereas the LV expression of oxidized low-density lipoprotein receptor 1 (Olr1) and arachidonate 15-lipoxygenase (Alox15) increased, with no changes in fatty acid transporter Cd36. An increased LV expression of angiotensin II receptors AT1 and AT2 was observed, with no changes in angiotensin I-converting enzyme expression. The Kalikrein-bradykinin system was upregulated with increased LV expression of kallikrein-related peptidases Klk8, Klk1c2, and Klk1c12 and bradykinin receptors B1 and B2 (Bdkrb1 and Bdkrb2), whereas the LV expression of inducible nitric oxide synthase 2 (Nos2) increased. LV expression in major molecular determinants involved in calcium-dependent myocardial contraction remained unchanged, except for an increased LV expression of calcium/calmodulin-dependent protein kinase II delta (Cacna1c) in response to OM. A single intravenous infusion of OM, in adult healthy rats, resulted in significant changes in the LV expression of genes regulating apoptosis, oxidative stress, metabolism, and cardiac contractility. Full article
(This article belongs to the Section Molecular Genetics and Genomics)
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9 pages, 375 KiB  
Article
Elevated Level of Cerebrospinal Fluid Pyruvate Dehydrogenase Kinase 4 Is a Predictive Biomarker of Clinical Outcome after Subarachnoid Hemorrhage
by Xuan Gao, Huasheng Zhang, Zheng Peng, Zong Zhuang and Wei Li
Brain Sci. 2022, 12(11), 1507; https://doi.org/10.3390/brainsci12111507 - 6 Nov 2022
Cited by 3 | Viewed by 1848
Abstract
Subarachnoid hemorrhage (SAH) is a central nervous system disease with high mortality and morbidity. Some independent factors valuable for prognosis prediction in patients with SAH are still lacking. In our earlier study, we found that PDK4 exerts a protective effect after SAH, primarily [...] Read more.
Subarachnoid hemorrhage (SAH) is a central nervous system disease with high mortality and morbidity. Some independent factors valuable for prognosis prediction in patients with SAH are still lacking. In our earlier study, we found that PDK4 exerts a protective effect after SAH, primarily by reducing oxidative stress and neuronal death via the ROS/ASK1/p38 signaling pathway. Therefore, we investigated the changes in the level of pyruvate dehydrogenase kinase 4 (PDK4) in patients after subarachnoid hemorrhage (SAH) and analyzed the value of the cerebrospinal fluid (CSF) PDK4 level in predicting the prognoses of patients with SAH after interventional embolization surgery. Some knee arthritis subjects who needed surgery were recruited as a control group. The results showed that PDK4 expression was elevated in the CSF of SAH patients compared with that of controls. PDK4 levels in CSF (OR = 4.525; 95% CI: 1.135–18.038; p = 0.032), time to surgery (OR = 0.795; 95% CI: 0.646–0.977; p = 0.029), and initial GCS scores (OR = 2.758; 95% CI: 0.177–43.106; p = 0.469) were independent prognostic risk factors for SAH patients after surgery. The receiver operating characteristic (ROC) curve showed PDK4 levels in CSF had a higher predictive value. Thus, PDK4 in CSF could be an independent prognostic risk factor for SAH patients after surgery. PDK4 has the potential to serve as a new therapeutic target and biomarker for use in the diagnosis of SAH severity and the prediction of recovery. Full article
(This article belongs to the Section Neuropharmacology and Neuropathology)
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14 pages, 2595 KiB  
Article
Anti-Metastatic Effect of Pyruvate Dehydrogenase Kinase 4 Inhibition in Bladder Cancer via the ERK, SRC, and JNK Pathways
by Eun Hye Lee, Jae-Wook Chung, Eunji Sung, Bo Hyun Yoon, Minji Jeon, Song Park, So Young Chun, Jun Nyung Lee, Bum Soo Kim, Hyun Tae Kim, Tae Hwan Kim, Seock Hwan Choi, Eun Sang Yoo, Tae Gyun Kwon, Ho Won Kang, Wun-Jae Kim, Seok Joong Yun, Sangkyu Lee and Yun-Sok Ha
Int. J. Mol. Sci. 2022, 23(21), 13240; https://doi.org/10.3390/ijms232113240 - 31 Oct 2022
Cited by 11 | Viewed by 3024
Abstract
Bladder cancer is a common global cancer with a high percentage of metastases and high mortality rate. Thus, it is necessary to identify new biomarkers that can be helpful in diagnosis. Pyruvate dehydrogenase kinase 4 (PDK4) belongs to the PDK family and plays [...] Read more.
Bladder cancer is a common global cancer with a high percentage of metastases and high mortality rate. Thus, it is necessary to identify new biomarkers that can be helpful in diagnosis. Pyruvate dehydrogenase kinase 4 (PDK4) belongs to the PDK family and plays an important role in glucose utilization in living organisms. In the present study, we evaluated the role of PDK4 in bladder cancer and its related protein changes. First, we observed elevated PDK4 expression in high-grade bladder cancers. To screen for changes in PDK4-related proteins in bladder cancer, we performed a comparative proteomic analysis using PDK4 knockdown cells. In bladder cancer cell lines, PDK4 silencing resulted in a lower rate of cell migration and invasion. In addition, a PDK4 knockdown xenograft model showed reduced bladder cancer growth in nude mice. Based on our results, PDK4 plays a critical role in the metastasis and growth of bladder cancer cells through changes in ERK, SRC, and JNK. Full article
(This article belongs to the Special Issue Signaling Transduction in Cancer Metabolism)
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16 pages, 4607 KiB  
Article
Transcriptomics Reveals Discordant Lipid Metabolism Effects between In Vitro Models Exposed to Elafibranor and Liver Samples of NAFLD Patients after Bariatric Surgery
by Joost Boeckmans, Alexandra Gatzios, Anja Heymans, Matthias Rombaut, Vera Rogiers, Joery De Kock, Tamara Vanhaecke and Robim M. Rodrigues
Cells 2022, 11(5), 893; https://doi.org/10.3390/cells11050893 - 4 Mar 2022
Cited by 10 | Viewed by 4763
Abstract
Background and aims: Non-alcoholic steatohepatitis (NASH) is a life-threatening stage of non-alcoholic fatty liver disease (NAFLD) for which no drugs have been approved. We have previously shown that human-derived hepatic in vitro models can be used to mimic key cellular mechanisms involved in [...] Read more.
Background and aims: Non-alcoholic steatohepatitis (NASH) is a life-threatening stage of non-alcoholic fatty liver disease (NAFLD) for which no drugs have been approved. We have previously shown that human-derived hepatic in vitro models can be used to mimic key cellular mechanisms involved in the progression of NASH. In the present study, we first characterize the transcriptome of multiple in vitro NASH models. Subsequently, we investigate how elafibranor, which is a peroxisome proliferator-activated receptor (PPAR)-α/δ agonist that has recently failed a phase 3 clinical trial as a potential anti-NASH compound, modulates the transcriptome of these models. Finally, we compare the elafibranor-induced gene expression modulation to transcriptome data of patients with improved/resolved NAFLD/NASH upon bariatric surgery, which is the only proven clinical NASH therapy. Methods: Human whole genome microarrays were used for the transcriptomics evaluation of hepatic in vitro models. Comparison to publicly available clinical datasets was conducted using multiple bioinformatic application tools. Results: Primary human hepatocytes (PHH), HepaRG, and human skin stem cell-derived hepatic progenitors (hSKP-HPC) exposed to NASH-inducing triggers exhibit up to 35% overlap with datasets of liver samples from NASH patients. Exposure of the in vitro NASH models to elafibranor partially reversed the transcriptional modulations, predicting an inhibition of toll-like receptor (TLR)-2/4/9-mediated inflammatory responses, NFκB-signaling, hepatic fibrosis, and leukocyte migration. These transcriptomic changes were also observed in the datasets of liver samples of patients with resolved NASH. Peroxisome Proliferator Activated Receptor Alpha (PPARA), PPARG Coactivator 1 Alpha (PPARGC1A), and Sirtuin 1 (SIRT1) were identified as the major common upstream regulators upon exposure to elafibranor. Analysis of the downstream mechanistic networks further revealed that angiopoietin Like 4 (ANGPTL4), pyruvate dehydrogenase kinase 4 (PDK4), and perilipin 2 (PLIN2), which are involved in the promotion of hepatic lipid accumulation, were also commonly upregulated by elafibranor in all in vitro NASH models. Contrarily, these genes were not upregulated in liver samples of patients with resolved NASH. Conclusion: Transcriptomics comparison between in vitro NASH models exposed to elafibranor and clinical datasets of NAFLD patients after bariatric surgery reveals commonly modulated anti-inflammatory responses, but discordant modulations of key factors in lipid metabolism. This discordant adverse effect of elafibranor deserves further investigation when assessing PPAR-α/δ agonism as a potential anti-NASH therapy. Full article
(This article belongs to the Special Issue The Role of PPARs in Disease II)
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16 pages, 2112 KiB  
Article
Cardioprotective Effects of Palmitoleic Acid (C16:1n7) in a Mouse Model of Catecholamine-Induced Cardiac Damage Are Mediated by PPAR Activation
by Iris Rosa Betz, Sarah Julia Qaiyumi, Madeleine Goeritzer, Arne Thiele, Sarah Brix, Niklas Beyhoff, Jana Grune, Robert Klopfleisch, Franziska Greulich, Nina Henriette Uhlenhaut, Ulrich Kintscher and Anna Foryst-Ludwig
Int. J. Mol. Sci. 2021, 22(23), 12695; https://doi.org/10.3390/ijms222312695 - 24 Nov 2021
Cited by 9 | Viewed by 3549
Abstract
Palmitoleic acid (C16:1n7) has been identified as a regulator of physiological cardiac hypertrophy. In the present study, we aimed to investigate the molecular pathways involved in C16:1n7 responses in primary murine cardiomyocytes (PCM) and a mouse model of isoproterenol (ISO)-induced cardiac damage. PCMs [...] Read more.
Palmitoleic acid (C16:1n7) has been identified as a regulator of physiological cardiac hypertrophy. In the present study, we aimed to investigate the molecular pathways involved in C16:1n7 responses in primary murine cardiomyocytes (PCM) and a mouse model of isoproterenol (ISO)-induced cardiac damage. PCMs were stimulated with C16:1n7 or a vehicle. Afterwards, RNA sequencing was performed using an Illumina HiSeq sequencer. Confirmatory analysis was performed in PCMs and HL-1 cardiomyocytes. For an in vivo study, 129 sv mice were orally treated with a vehicle or C16:1n7 for 22 days. After 5 days of pre-treatment, the mice were injected with ISO (25 mg/kg/d s. c.) for 4 consecutive days. Cardiac phenotyping was performed using echocardiography. In total, 129 genes were differentially expressed in PCMs stimulated with C16:1n7, including Angiopoietin-like factor 4 (Angptl4) and Pyruvate Dehydrogenase Kinase 4 (Pdk4). Both Angptl4 and Pdk4 are proxisome proliferator-activated receptor α/δ (PPARα/δ) target genes. Our in vivo results indicated cardioprotective and anti-fibrotic effects of C16:1n7 application in mice. This was associated with the C16:1n7-dependent regulation of the cardiac PPAR-specific signaling pathways. In conclusion, our experiments demonstrated that C16:1n7 might have protective effects on cardiac fibrosis and inflammation. Our study may help to develop future lipid-based therapies for catecholamine-induced cardiac damage. Full article
(This article belongs to the Special Issue Recent Advances in Molecular Research of Metabolic Disorders)
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13 pages, 1506 KiB  
Article
Acute Administration of Exogenous Lactate Increases Carbohydrate Metabolism during Exercise in Mice
by Inkwon Jang, Jisu Kim, Sunghwan Kyun, Deunsol Hwang and Kiwon Lim
Metabolites 2021, 11(8), 553; https://doi.org/10.3390/metabo11080553 - 21 Aug 2021
Cited by 9 | Viewed by 3730
Abstract
In this study, we investigated the effects of exogenous lactate administration before exercise on energy substrate utilization during exercise. Mice were divided into exercise control (EX) and exercise with lactate intake (EXLA) groups; saline/lactate was administered 30 min before exercise. Respiratory gas was [...] Read more.
In this study, we investigated the effects of exogenous lactate administration before exercise on energy substrate utilization during exercise. Mice were divided into exercise control (EX) and exercise with lactate intake (EXLA) groups; saline/lactate was administered 30 min before exercise. Respiratory gas was measured during moderate intensity treadmill exercise (30 min). Immediately after exercise, blood, liver, and skeletal muscle samples were collected and mRNA levels of energy metabolism-related and metabolic factors were analyzed. At 16–30 min of exercise, the respiratory exchange ratio (p = 0.045) and carbohydrate oxidation level (p = 0.014) were significantly higher in the EXLA than in the EX group. Immediately after exercise, the muscle and liver glycogen content and blood glucose level of the EXLA group were lower than those of the EX group. In addition, muscle mRNA levels of HK2 (hexokinase 2; p = 0.009), a carbohydrate oxidation-related factor, were higher in the EXLA than in the EX group, whereas the expression of PDK4 (pyruvate dehydrogenase kinase 4; p = 0.001), CS (citrate synthase; p = 0.045), and CD36 (cluster of differentiation 36; p = 0.002), factors related to oxidative metabolism, was higher in the EX than in the EXLA group. These results suggest that lactate can be used in various research fields to promote carbohydrate metabolism. Full article
(This article belongs to the Section Animal Metabolism)
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15 pages, 1802 KiB  
Article
Five Days Periodic Fasting Elevates Levels of Longevity Related Christensenella and Sirtuin Expression in Humans
by Stephanie Lilja, Carina Stoll, Ulrike Krammer, Berit Hippe, Kalina Duszka, Tewodros Debebe, Ingrid Höfinger, Jürgen König, Angelika Pointner and Alexander Haslberger
Int. J. Mol. Sci. 2021, 22(5), 2331; https://doi.org/10.3390/ijms22052331 - 26 Feb 2021
Cited by 41 | Viewed by 11805
Abstract
Periodic fasting (PF) is an increasingly popular approach that assists in the management of metabolic and inflammatory diseases as well as in preventing mechanisms involved in aging. However, little is known about the effects of fasting on gut microbiota and its impact on [...] Read more.
Periodic fasting (PF) is an increasingly popular approach that assists in the management of metabolic and inflammatory diseases as well as in preventing mechanisms involved in aging. However, little is known about the effects of fasting on gut microbiota and its impact on the epigenetic regulation of metabolically relevant enzymes, especially sirtuins (SIRTs). We analyzed the effect of periodic fasting on the human gut microbiota, SIRTs expression, and mitochondrial content in 51 males and females. The participants fasted under supervision for five consecutive days following the Buchinger fasting guidelines. Ketogenesis, selected mRNAs, miRNAs, mitochondrial (mt) DNA, and gut composition were analyzed before and after PF. PF triggered a significant switch in metabolism, as indicated by the increase in ß-hydroxybutyrate (BHB) and pyruvate dehydrogenase kinase isoform 4 (PDK4) expression in the capillary blood. MtDNA, SIRT1, SIRT3, and miRlet7b-5p expression in blood cells were elevated, whereas SIRT6 and miR125b-5p were not affected. Following fasting, gut microbiota diversity increased, and a statistically significant correlation between SIRT1 gene expression and the abundance of Prevotella and Lactobacillus was detected. The abundance of longevity related Christensenella species increased after fasting and inversely correlated with age as well as body mass index (BMI). Thus, this represents the first study that showing that fasting not only changes the composition of the gut microbiota, making it more diverse, but also affects SIRT expression in humans. Full article
(This article belongs to the Special Issue Nutrient-Gene Interactions)
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17 pages, 2731 KiB  
Article
Acriflavine, a Potent Inhibitor of HIF-1α, Disturbs Glucose Metabolism and Suppresses ATF4-Protective Pathways in Melanoma under Non-Hypoxic Conditions
by Román Martí-Díaz, María F. Montenegro, Juan Cabezas-Herrera, Colin R. Goding, José Neptuno Rodríguez-López and Luis Sánchez-del-Campo
Cancers 2021, 13(1), 102; https://doi.org/10.3390/cancers13010102 - 31 Dec 2020
Cited by 25 | Viewed by 4495
Abstract
Hypoxia-inducible factor (HIF)-1α is constitutively expressed in melanoma cells under normoxic conditions and its elevated expression correlates with the aggressiveness of melanoma tumors. Here, we used acriflavine, a potent inhibitor of HIF-1α dimerization, as a tool to investigate whether HIF-1α-regulated pathways contribute to [...] Read more.
Hypoxia-inducible factor (HIF)-1α is constitutively expressed in melanoma cells under normoxic conditions and its elevated expression correlates with the aggressiveness of melanoma tumors. Here, we used acriflavine, a potent inhibitor of HIF-1α dimerization, as a tool to investigate whether HIF-1α-regulated pathways contribute to the growth of melanoma cells under normoxia. We observed that acriflavine differentially modulated HIF-1α-regulated targets in melanoma under normoxic conditions, although acriflavine treatment resulted in over-expression of vascular endothelial growth factor (VEGF), its action clearly downregulated the expression of pyruvate dehydrogenase kinase 1 (PDK1), a well-known target of HIF-1α. Consequently, downregulation of PDK1 by acrifavine resulted in reduced glucose availability and suppression of the Warburg effect in melanoma cells. In addition, by inhibiting the AKT and RSK2 phosphorylation, acriflavine also avoided protective pathways necessary for survival under conditions of oxidative stress. Interestingly, we show that acriflavine targets activating transcription factor 4 (ATF4) for proteasomal degradation while suppressing the expression of microphthalmia-associated transcription factor (MITF), a master regulator of melanocyte development and a melanoma oncogene. Since acriflavine treatment results in the consistent death of melanoma cells, our results suggest that inhibition of HIF-1α function in melanoma could open new avenues for the treatment of this deadly disease regardless of the hypoxic condition of the tumor. Full article
(This article belongs to the Special Issue Inhibition of HIFs as an Anti-Cancer Strategy)
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