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Cancer cells must develop strategies to adapt to the dynamically changing stresses caused by intrinsic or extrinsic processes, or therapeutic agents. Metabolic adaptability is crucial to mitigate such challenges. Considering metabolism as a central node of adaptability, it is focused on an energy sensor, the AMP‐activated protein kinase (AMPK). In a subtype of pancreatic ductal adenocarcinoma (PDAC) elevated AMPK expression and phosphorylation is identified. Using drug repurposing that combined screening experiments and chemoproteomic affinity profiling, it is identified and characterized PF‐3758309, initially developed as an inhibitor of PAK4, as an AMPK inhibitor. PF‐3758309 shows activity in pre‐clinical PDAC models, including primary patient‐derived organoids. Genetic loss‐of‐function experiments showed that AMPK limits the induction of ferroptosis, and consequently, PF‐3758309 treatment restores the sensitivity toward ferroptosis inducers. The work established a chemical scaffold for the development of specific AMPK‐targeting compounds and deciphered the framework for the development of AMPK inhibitor‐based combination therapies tailored for PDAC. [ABSTRACT FROM AUTHOR]

Hepatic polypeptide nutrient solution (HP) is a mixture of hepatoprotective peptides derived from fresh porcine liver with various effects. However, the role and mechanisms of HP in nonalcoholic fatty liver disease (NAFLD) are still not well understood. We investigated the effects of HP NAFLD rats induced by high‐cholesterol diet (HCD) and its underlying mechanisms. Rats were provided with HCD for 4 weeks and then received HP or metformin after 2 weeks of HCD feeding. The study found that HP reduced cholesterol and triglyceride levels in rats with NAFLD (all p <.05). Histopathological examination also showed that HP improved the liver lesions induced by the HCD diet. Furthermore, the oxidative stress and inflammatory responses of NAFLD rats treated with HP were also improved. In addition, it was discovered that HP triggered the activation of AMPK and decreased the expression of SREBP‐1c and FAS while enhancing the expression of PPAR α and CPT‐1 in liver. These findings indicated that HP might have therapeutic potential for NAFLD, possibly via activating AMPK signaling pathway. [ABSTRACT FROM AUTHOR]

Glycogen shortage during fasting coincides with dramatic changes in hepatic adenine nucleotide levels. The aim of this work was to study the relevance of liver glycogen in the regulation of the hepatic energy state during food deprivation. To this end, we examined the response of mice with sustained increased liver glycogen content to prolonged fasting. In order to increase hepatic glycogen content, we generated mice that overexpress protein targeting to glycogen (PTG) in the liver (PTGOE mice). Control and PTGOE mice were fed ad libitum or fasted for 36 h. Upon fasting, PTGOE mice retained significant hepatic glycogen stores and maintained hepatic energy status. Furthermore, we show that liver glycogen controls insulin sensitivity, gluconeogenesis, lipid metabolism, and ketogenesis upon nutrient deprivation. [ABSTRACT FROM AUTHOR]

Trehalose-6-phosphate is a ‘sugar signal’ that regulates plant metabolism and development. The Arabidopsis genome encodes trehalose-6-phosphate synthase (TPS) and trehalose-6-phosphatase (TPP) enzymes. It also encodes class II proteins (TPS isoforms 5–11) that contain both TPS-like and TPP-like domains, although whether these have enzymatic activity is unknown. In this paper, we show that TPS5, 6 and 7 are phosphoproteins that bind to 14-3-3 proteins, by using 14-3-3 affinity chromatography, 14-3-3 overlay assays, and by co-immunoprecipitating TPS5 and 14-3-3 isoforms from cell extracts. GST–TPS5 bound to 14-3-3s after in vitro phosphorylation at Ser22 and Thr49 by either mammalian AMP-activated protein kinase (AMPK) or partially purified plant Snf1-related protein kinase  1 (SnRK1s). Dephosphorylation of TPS5, or mutation of either Ser22 or Thr49, abolished binding to 14-3-3s. Ser22 and Thr49 are both conserved in TPS5, 7, 9 and 10. When GST–TPS5 was expressed in human HEK293 cells, Thr49 was phosphorylated in response to 2-deoxyglucose or phenformin, stimuli that activate the AMPK via the upstream kinase LKB1. 2-deoxyglucose stimulated Thr49 phosphorylation of endogenous TPS5 in Arabidopsis cells, whereas phenformin did not. Moreover, extractable SnRK1 activity was increased in Arabidopsis cells in response to 2-deoxyglucose. The plant kinase was inactivated by dephosphorylation and reactivated by phosphorylation with human LKB1, indicating that elements of the SnRK1/AMPK pathway are conserved in Arabidopsis and human cells. We hypothesize that coordinated phosphorylation and 14-3-3 binding of nitrate reductase (NR), 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase (F2KP) and class II TPS isoforms mediate responses to signals that activate SnRK1. [ABSTRACT FROM AUTHOR]

Certain amino acids, like glutamine and leucine, induce an anabolic response in liver. They activate p70 ribosomal protein S6 kinase (p70S6K) and acetyl-CoA carboxylase (ACC) involved in protein and fatty acids synthesis, respectively. In contrast, the AMP-activated protein kinase (AMPK), which senses the energy state of the cell and becomes activated under metabolic stress, inactivates by phosphorylation key enzymes in biosynthetic pathways thereby conserving ATP. In this paper, we studied the effect of AMPK activation and of protein phosphatase inhibitors, on the amino-acid-induced activation of p70S6K and ACC in hepatocytes in suspension. AMPK was activated under anoxic conditions or by incubation with 5-aminoimidazole-4-carboxyamide ribonucleoside (AICAr) or oligomycin, an inhibitor of mitochondrial oxidative phosphorylation. Incubation of hepatocytes with amino acids activated p70S6K via multiple phosphorylation. It also activated ACC by a phosphatase-dependent mechanism but did not modify AMPK activation. Conversely, the amino-acid-induced activation of both ACC and p70S6K was blocked or reversed when AMPK was activated. This AMPK activation increased Ser79 phosphorylation in ACC but decreased Thr389 phosphorylation in p70S6K. Protein phosphatase inhibitors prevented p70S6K activation when added prior to the incubation with amino acids, whereas they enhanced p70S6K activation when added after the preincubation with amino acids. It is concluded that (a) AMPK blocks amino-acid-induced activation of ACC and p70S6K, directly by phosphorylating Ser79 in ACC, and indirectly by inhibiting p70S6K phosphorylation, and (b) both activation and inhibition of protein phosphatases are involved in the activation of p70S6K by amino acids. p70S6K adds to an increasing list of targets of AMPK in agreement with the inhibition of energy-consuming biosynthetic pathways. [ABSTRACT FROM AUTHOR]

Background and Purpose: Nitazoxanide is a therapeutic anthelmintic drug. Our previous studies found that nitazoxanide and its metabolite tizoxanide activated adenosine 5′‐monophosphate‐activated protein kinase (AMPK) and inhibited signal transducer and activator of transcription 3 (STAT3) signals. As AMPK activation and/or STAT3 inhibition are targets for treating pulmonary fibrosis, we hypothesized that nitazoxanide would be effective in experimental pulmonary fibrosis. Experimental Approach: The mitochondrial oxygen consumption rate of cells was measured by using the high‐resolution respirometry system Oxygraph‐2K. The mitochondrial membrane potential of cells was evaluated by tetramethyl rhodamine methyl ester (TMRM) staining. The target protein levels were measured by using western blotting. The mice pulmonary fibrosis model was established through intratracheal instillation of bleomycin. The examination of the lung tissues changes were carried out using haematoxylin and eosin (H&E), and Masson staining. Key Results: Nitazoxanide and tizoxanide activated AMPK and inhibited STAT3 signalling in human lung fibroblast cells (MRC‐5 cells). Nitazoxanide and tizoxanide inhibited transforming growth factor‐β1 (TGF‐β1)‐induced proliferation and migration of MRC‐5 cells, collagen‐I and α‐smooth muscle cell actin (α‐SMA) expression, and collagen‐I secretion from MRC‐5 cells. Nitazoxanide and tizoxanide inhibited epithelial–mesenchymal transition (EMT) and inhibited TGF‐β1‐induced Smad2/3 activation in mouse lung epithelial cells (MLE‐12 cells). Oral administration of nitazoxanide reduced the bleomycin‐induced mice pulmonary fibrosis and, in the established bleomycin‐induced mice, pulmonary fibrosis. Delayed nitazoxanide treatment attenuated the fibrosis progression. Conclusions and Implications: Nitazoxanide improves the bleomycin‐induced pulmonary fibrosis in mice, suggesting a potential application of nitazoxanide for pulmonary fibrosis treatment in the clinic. [ABSTRACT FROM AUTHOR]

Growing evidence points to impaired autophagy as one of the major factors implicated in the pathophysiology of Parkinson's disease (PD). Autophagy is a downstream target of adenosine monophosphate‐activated protein kinase (AMPK). Inosine has already demonstrated a neuroprotective effect against neuronal loss in neurodegenerative diseases, mainly due its anti‐inflammatory and antioxidant properties. We, herein, aimed at investigating the neuroprotective effects of inosine against rotenone‐induced PD in rats and to focus on the activation of AMPK‐mediated autophagy. Inosine successfully increased p‐AMPK/AMPK ratio in PD rats and improved their motor performance and muscular co‐ordination (assessed by rotarod, open field, and grip strength tests, as well as by manual gait analysis). Furthermore, inosine was able to mitigate the rotenone‐induced histopathological alterations and to restore the tyrosine hydroxylase immunoreactivity in PD rats' substantia nigra. Inosine‐induced AMPK activation resulted in an autophagy enhancement, as demonstrated by the increased striatal Unc‐S1‐like kinase1 and beclin‐1 expression, and also by the increment light chain 3II to light chain 3I ratio, along with the decline in striatal mammalian target of rapamycin and p62 protein expressions. The inosine‐induced stimulation of AMPK also attenuated neuronal apoptosis and promoted antioxidant activity. Unsurprisingly, these neuroprotective effects were antagonized by a preadministration of dorsomorphin (an AMPK inhibitor). In conclusion, inosine exerted neuroprotective effects against the rotenone‐induced neuronal loss via an AMPK activation and through the restoration of the imbalance between autophagy and apoptosis. These findings support potential application of inosine in PD treatment. [ABSTRACT FROM AUTHOR]

Natural pentacyclic triterpenoid oleanolic acid (OA) is used as an over‐the‐counter drug for acute and chronic hepatitis. However, clinical use of OA‐containing herbal medicines has been reported to cause cholestasis, and the specific mechanism is unknown. The purpose of this study was to explore how OA causes cholestatic liver injury via the AMP‐activated protein kinase (AMPK)‐farnesoid X receptor (FXR) pathway. In animal experiments, it was found that OA treatment activated AMPK and decreased FXR and bile acid efflux transport proteins expression. When intervened with the specific inhibitor Compound C (CC), it was observed that AMPK activation was inhibited, the reduction of FXR and bile acid efflux transport protein expression was effectively alleviated, serum biochemical indicators were significantly reduced, and liver pathological damage brought about by OA was effectively ameliorated. In addition, OA was found to downregulate the expression of FXR and bile acid efflux transport proteins by activating the ERK1/2‐LKB1‐AMPK pathway in cellular experiments. The ERK1/2 inhibitor U0126 was used to pretreat primary hepatocytes, and this drastically reduced the phosphorylation levels of LKB1 and AMPK. The inhibition effects of OA on FXR and bile acid efflux transport proteins were also effectively alleviated after pretreatment with CC. In addition, OA‐induced downregulation of FXR gene and protein expression levels was significantly prevented after silencing AMPKα1 expression in AML12 cells. Our study demonstrated that OA inhibited FXR and bile acid efflux transporters through the activation of AMPK, thus leading to cholestatic liver injury. Oleanolic acid (OA) is used as an over‐the‐counter drug for the treatment of liver diseases, but clinical use of OA‐containing herbal medicines can lead to cholestasis. In this study, OA was found to induce liver injury by activating AMPK phosphorylation through the ERK1/2‐LKB1 pathway and inhibiting FXR and its downstream targets. Silencing of AMPKα1 in cells attenuated OA‐induced FXR inhibition. Pharmacological inhibition of AMPK in cells and animals has a protective effect against OA‐induced liver injury. [ABSTRACT FROM AUTHOR]

Nonalcoholic fatty liver disease (NAFLD) is a prevalent chronic liver disease around the world, imposing severe threats on human health. Unfortunately, no clinically approved drugs are available for use as yet. Baicalin (BA) is reported to have hepatoprotective effects, and it is not clear whether BA can treat NAFLD and how. Here, a high‐fat diet (HFD)‐induced NAFLD mouse model was established to explore the protective roles and mechanisms of BA against HFD‐induced NAFLD. Physiochemical results showed that BA exhibited significantly protective effects against HFD‐induced NAFLD in mice. Liver transcriptomic analysis revealed that BA attenuated HFD‐induced NAFLD via activating AMPK pathway, which was confirmed by the AMPK inhibitor Compound C. Additionally, the expression changes of AMPK downstream genes demonstrated that BA exerted ameliorative effects against NAFLD through AMPK‐mediated inhibition of SREBP1 and NF‐κB pathways, and activation of Nrf2 pathway. Taken together, our study reveals the protective roles of BA against HFD‐caused NAFLD through AMPK‐mediated modulation of SREBP1/Nrf2/NF‐κB pathways, suggesting that BA has potential drug development implications. Most importantly, our study creates a paradigm through the combination of molecular biology and bioinformatics for further studies of action mechanisms of biomolecules combating diseases. [ABSTRACT FROM AUTHOR]

This work describes the synthesis of series hydrobromides of N‐(4‐biphenyl)methyl–N′‐dialkylaminoethyl‐2‐iminobenzimidazoles, which, due to the presence of two privileged structural fragments (benzimidazole and biphenyl moieties), can be considered as bi‐privileged structures. Compound 7a proved to activate AMP‐activated kinase (AMPK) and simultaneously inhibit protein tyrosine phosphatase 1B (PTP1B) with similar potency. This renders it an interesting prototype of potential antidiabetic agents with a dual‐target mechanism of action. Using prove of concept in vivo study, we show that dual‐targeting compound 7a has a disease‐modifying effect in a rat model of type 2 diabetes mellitus via improving insulin sensitivity and lipid metabolism. [ABSTRACT FROM AUTHOR]

Perfluorooctane sulfonate (PFOS) is a hepatotoxic environmental organic pollutant that can cause aberrant lipid accumulation in the liver. However, the molecular mechanism underlying PFOS‐induced hepatic steatosis remains unclear. Our research showed that subchronic PFOS exposure inhibited AMP‐activated protein kinase (AMPK) phosphorylation, leading to increased acetyl‐CoA carboxylase (ACC) activity, attenuated fatty acid β‐oxidation, and consequent liver lipid accumulation. We found that 1 mg/kg/day PFOS exposure significantly aggravated steatosis in high‐fat diet (HFD)‐fed mice, along with reduced AMPK activity. Oil Red O results showed that PFOS exposure caused fat accumulation in HepG2 cells. As predicted, PFOS treatment reduced the level of phosphorylated AMPK in a concentration‐dependent manner, leading to subsequent increase in ACC activity and lipid droplet accumulation in HepG2 cells. Treatment with 200‐μM AMPK agonist AICAR alleviated PFOS‐induced ACC activation and lipid accumulation. In summary, our data highlight a crucial role of AMPK/ACC pathway in PFOS‐mediated liver lipid metabolic disorders. Epidemiological and experimental animal data suggest an involvement of perfluorooctane sulfonate (PFOS) exposure in aberrant hepatic lipid metabolism, whose mechanism remains largely elusive. Herein, we revealed that subchronic PFOS exposure augmented high‐fat diet (HFD)‐induced hepatic lipid accumulation and steatosis via AMP‐activated protein kinase (AMPK) phosphorylation and consequent acetyl‐CoA carboxylase (ACC) activation. Treatment with AICAR, an AMPK agonist, attenuated PFOS‐induced ACC activation and lipid accumulation, suggesting a critical role of the AMPK/ACC pathway in PFOS‐mediated disturbance of hepatic lipid metabolism. [ABSTRACT FROM AUTHOR]

Though icariside E4 (IE4) is known to have anti-noceptive, anti-oxidant, antiAlzheimer and anti-inflammatory effects, there was no evidence on the effect of IE4 on lipid metabolism so far. Hence, the hypolipogenic mechanism of IE4 was investigated in HepG2 hepatocellular carcinoma cells (HCCs) in association with MID1 Interacting Protein 1(MID1IP1) and AMPK signaling. Here, IE4 did not show any toxicity in HepG2 cells, but reduced lipid accumulation in HepG2 cells by Oil Red O staining. MID1IP1 depletion decreased the expression of SREBP-1c and fatty acid synthase (FASN) and induced phosphorylation of ACC in HepG2 cells. Indeed, IE4 activated phosphorylation of AMPK and ACC and inhibited the expression of MID1IP1 in HepG2 cells. Furthermore, IE4 suppressed the expression of SREBP-1c, liver X receptor-α (LXR), and FASN for de novo lipogenesis in HepG2 cells. Interestingly, AMPK inhibitor compound C reversed the ability of IE4 to reduce MID1IP1, SREBP-1c, and FASN and activate phosphorylation of AMPK/ACC in HepG2 cells, indicating the important role of AMPK/ACC signaling in IE4-induced hypolipogenic effect. Taken together, these findings suggest that IE4 has hypolipogenic potential in HepG2 cells via activation of AMPK and inhibition of MID1IP1 as a potent candidate for treatment of fatty liver disease. [ABSTRACT FROM AUTHOR]

Background and Purpose: The anthelmintic drug nitazoxanide has a mitochondrial uncoupling effect. Mitochondrial uncouplers have been proven to inhibit smooth muscle cell proliferation and migration, inhibit NLRP3 inflammasome activation of macrophages and improve dyslipidaemia. Therefore, we aimed to demonstrate that nitazoxanide would protect against atherosclerosis. Experimental Approach: The mitochondrial oxygen consumption of cells was measured by using the high‐resolution respirometry system, Oxygraph‐2K. The proliferation and migration of A10 cells were measured by using Edu immunofluorescence staining, wound‐induced migration and the Boyden chamber assay. Protein levels were measured by using the western blot technique. ApoE (−/−) mice were fed with a Western diet to establish an atherosclerotic model in vivo. Key Results: The in vitro experiments showed that nitazoxanide and tizoxanide had a mitochondrial uncoupling effect and activated cellular AMPK. Nitazoxanide and tizoxanide inhibited serum‐ and PDGF‐induced proliferation and migration of A10 cells. Nitazoxanide and tizoxanide inhibited NLRP3 inflammasome activation in RAW264.7 macrophages, the mechanism by which involved the AMPK/IκBα/NF‐κB pathway. Nitazoxanide and tizoxanide also induced autophagy in A10 cells and RAW264.7 macrophages. The in vivo experiments demonstrated that oral administration of nitazoxanide reduced the increase in serum IL‐1β and IL‐6 levels and suppressed atherosclerosis in Western diet‐fed ApoE (−/−) mice. Conclusion and Implications: Nitazoxanide inhibits the formation of atherosclerotic plaques in ApoE (−/−) mice fed on a Western diet. In view of nitazoxanide being an antiprotozoal drug already approved by the FDA, we propose it as a novel anti‐atherosclerotic drug with clinical translational potential. [ABSTRACT FROM AUTHOR]

As one of the most important organs in animals, the intestine is responsible for nutrient absorption and acts as a barrier between the body and the environment. Intestinal physiology and function require the participation of energy. 5′‐adenosine monophosphate‐activated protein kinase (AMPK), a classical and highly expressed energy regulator in intestinal cells, regulates the process of nutrient absorption and barrier function and is also involved in the therapy of intestinal diseases. Studies have yielded findings that AMPK regulates the absorption of glucose, amino acids, and fatty acids in the intestine primarily by regulating transportation systems, as we detailed here. Moreover, AMPK is involved in the regulation of the intestinal mechanical barrier and immune barrier through manipulating the expression of tight junctions, antimicrobial peptides, and secretory immunoglobulins. In addition, AMPK also participates in the regulation of intestinal diseases, which indicates that AMPK is a promising therapeutic target for intestinal diseases and cancer. In this review, we summarized the current understanding regarding how AMPK regulates intestinal nutrient absorption, barrier function, and intestinal diseases. [ABSTRACT FROM AUTHOR]

Acetaminophen (APAP), one of the most widely used antipyretics and analgesics, principally results in acute liver injury (ALI) in developed countries when taken overdose. Ferulic acid (FA) is a natural polyphenol compound existing in many plants that has free radical scavenging, anti‐inflammatory, and liver‐protective properties. However, the effect and underlying mechanism of FA in treating APAP‐induced ALI have not been fully elucidated. Herein, we established a mouse model of APAP‐induced ALI and used APAP‐stimulated MPHs for biochemical assessment of molecular parameters. After constructing networks and obtaining predicted targets from public databases, we further verified the putative pathways using immune‐blotting assays both in vivo and in vitro. The reign of liver necrosis, serum levels of ALT and AST, and oxidative stress in livers significantly elevated after APAP treatment, which were almost recovered back to normal levels by FA administration. In addition, FA significantly upregulated the APAP‐induced downregulation of hepatic specific markers, including HNF4a, Foxa2, and ALB. Then, the results of functional enrichment indicated the possible signaling pathways of FA against APAP challenge, mainly including AMPK, autophagy, apoptosis, and other metabolic process. Furthermore, FA markedly reversed the APAP‐induced decline of mitochondria membrane potential, increased ratio of BAX/BCL2 and CASPASE 3 expression, and promoted autophagy flux of hepatocytes by upregulating AMPK phosphorylation, which were abrogated by a specific AMPK inhibitor, compound C. Overall, the hepatoprotective effect of FA on APAP‐induced ALI might be associated with anti‐oxidant and anti‐apoptosis, which were at least partly attributed to AMPK‐mediated protective autophagy. [ABSTRACT FROM AUTHOR]

Aerobic exercise is an effective intervention in preventing obesity and is also an important factor associated with thermogenesis. There is an increasing interest in the factors and mechanisms induced by aerobic exercise that can influence the metabolism and thermogenic activity in an individual. Recent studies suggest that exercise induced circulating factors (known as 'exerkines'), which are able to modulate activation of brown adipose tissue (BAT) and browning of white adipose tissue. However, the underlying molecular mechanisms associated with the effect of exercise‐induced peripheral factors on BAT activation remain poorly understood. Furthermore, the role of exercise training in BAT activation is still debatable. Hence, the purpose of our study is to assess whether exercise training affects the expression of uncoupled protein 1 (UCP1) in brown adipocytes via release of different blood factors. Four weeks of exercise training significantly decreased the body weight gain and fat mass gain. Furthermore, trained mice exhibit higher levels of energy expenditure and UCP1 expression than untrained mice. Surprisingly, treatment with serum from exercise‐trained mice increased the expression of UCP1 in differentiated brown adipocytes. To gain a better understanding of these mechanisms, we analysed the conditioned media obtained after treating the C2C12 myotubes with an AMP‐activated protein kinase (AMPK) activator (AICAR; 5‐aminoimidazole‐4‐carboxamide ribonucleotide), which leads to an increased expression of UCP1 when added to brown adipocytes. Our observations suggest the possibility of aerobic exercise‐induced BAT activation via activation of AMPK in skeletal muscles. Key points: Exercise promotes thermogenesis by activating uncoupling protein 1 (UCP1), which leads to a decrease in the body weight gain and body fat content. However, little is known about the role of exerkines in modulating UCP1 expression and subsequent brown adipose tissue (BAT) activation.Four weeks of voluntary wheel‐running exercise reduces body weight and fat content.Exercise induces the increase in AMP‐activated protein kinase (AMPK) and slow‐type muscle fibre marker genes in skeletal muscles and promotes UCP1 expression in white and brown adipose tissues.Incubation of brown adipocytes with serum isolated from exercise‐trained mice significantly increased their UCP1 gene and protein levels; moreover, conditioned media of AMPK‐activator‐treated C2C12 myotubes induces increased UCP1 expression in brown adipocytes.These results show that aerobic exercise‐induced skeletal muscle AMPK has a significant effect on UCP1 expression in BAT. [ABSTRACT FROM AUTHOR]

Background and Purpose: Ilexgenin A is a triterpenoid from ShanLv Cha with beneficial effects on metabolic homeostasis. We investigated whether ilexgenin A could inhibit hepatic de novo fatty acid synthesis via the interfering with SREBP1 maturation.Experimental Approach: The effects of Ilexgenin A on CRTC2 translocation and SREBP1 maturation were investigated in the liver of fasted mice and hepatocytes exposed to saturated fatty acids. The effect of Iilexgenin A on hepatic lipid accumulation was also observed in high-fat diet fed mice.Key Results: Sec23A and Sec31A are two subunits of COPII complex and their interaction is essential for the processing of SREBP1 maturation. Ilexgenin A activates AMPK by reducing cellular energy and preventing cytoplasmic CRTC2 to compete with Sec23A for binding to Sec31A under nutrient-rich conditions. Consequently, ilexgenin A impaired COPII-dependent SREBP1 maturation via disrupting Sec31A-Sec23A interaction, leading to the inhibition of de novo fatty acid synthesis in the liver. In contrast, mTORC1 phosphorylated Ser136 of CRTC2, facilitating the formation of Sec31A-Sec23A interaction to promote SREBP1 maturation, whereas this action was reversed by ilexgenin A in an AMPK-dependent manner. Ilexgenin A protected CRTC2 function and restrained hepatic lipogenic response in high fat diet-fed mice, providing in vivo evidence to support the beneficial effects of ilexgenin A on lipid metabolism.Conclusions and Implications: Ilexgenin A activated AMPK and restrained CRTC2 to the cytoplasm to prevent SREBP1 maturation via impairing COPII function in the liver. This suggests that CRTC2 might be a potential target for pharmacological intervention to prevent hepatic lipid deposition.Linked Articles: This article is part of a themed issue on Preclinical Models for Cardiovascular disease research (BJP 75th Anniversary). To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v179.5/issuetoc. [ABSTRACT FROM AUTHOR]

Metastatic uveal melanoma (UM) responds poorly to targeted therapies and immune checkpoint inhibitors. Loss of BRCA1‐associated protein 1 (BAP1) via inactivating mutations in the BAP1 gene is associated with UM progression. Thus, molecular alterations caused by BAP1 dysfunction may be novel therapeutic targets for metastatic UM. Here, we found that phosphorylation of AMP‐dependent kinase (AMPK) was elevated in BAP1‐altered (or mutant) compared to BAP1‐unaltered (or wild‐type [WT]) UM tumors. As a readout of AMPK pathway activation, phosphorylation of an AMPK downstream effector, acetyl‐CoA‐carboxylase (ACC), was also elevated. BAP1 re‐expression in BAP1‐null UM cell lines decreased phospho‐AMPK (pAMPK) and phospho‐ACC (pACC) levels. AMPK phosphorylation is mediated by calcium/calmodulin dependent protein kinase kinase 2 (CaMKK2) and potentially liver kinase B1 (LKB1) in BAP1 mutant UM cells. Knockdown of AMPKα1/2 reduced the viability of BAP1 mutant UM cells, indicating a survival function of AMPK in BAP1 mutant UM. Our data suggest that the AMPK pathway is an important mechanism mediating the survival of BAP1 mutant UM. Targeting the AMPK pathway may be a novel therapeutic strategy for metastatic UM. [ABSTRACT FROM AUTHOR]

Background and Purpose: Obesity is a risk factor for the development of chronic kidney disease independent of diabetes, hypertension and other co‐morbidities. Obesity‐associated nephropathy is linked to dysregulation of the cell energy sensor AMP‐activated protein kinase (AMPK). We aimed here to assess whether impairment of AMPK activity may cause renal arterial dysfunction in obesity and to evaluate the therapeutic potential of activating renal AMPK. Experimental Approach Effects of the AMPK activator A769662 were assessed on intrarenal arteries isolated from ob/ob mice and obese Zucker rats and then mounted in microvascular myographs. Superoxide and hydrogen peroxide production were measured by chemiluminescence and fluorescence, respectively, and protein expression was analysed by western blotting. Key Results: Endothelium‐dependent vasodilation and PI3K/Akt/eNOS pathway were impaired in preglomerular arteries from genetically obese rats and mice, along with impaired arterial AMPK activity and blunted relaxations induced by the AMPK activator A769662. Acute ex vivo exposure to A769662 restored endothelial function and enhanced activity of PI3K/Akt/eNOS pathway in obese rats, whereas in vivo treatment with A769662 improved metabolic state and ameliorated endothelial dysfunction, reduced inflammatory markers and vascular oxidative stress in renal arteries and restored redox balance in renal cortex of obese mice. Conclusion and Implications: These results demonstrate that AMPK dysregulation underlies obesity‐associated kidney vascular dysfunction and activation of AMPK improves metabolic state, protects renal endothelial function and exerts potent vascular antioxidant and anti‐inflammatory effects. The beneficial effects of vascular AMPK activation might represent a promising therapeutic approach to the treatment of obesity‐related kidney injury. [ABSTRACT FROM AUTHOR]

Loss of function of the cystic fibrosis transmembrane conductance regulator (CFTR) causes cystic fibrosis (CF). In the lungs, this manifests as immune cell infiltration and bacterial infections, leading to tissue destruction. Previous work has determined that acute bacterial sphingomyelinase (SMase) decreases CFTR function in bronchial epithelial cells from individuals without CF (nHBEs) and with CF (cfHBEs, homozygous ΔF508‐CFTR mutation). This study focuses on exploring the mechanisms underlying this effect. SMase increased the abundance of dihydroceramides, a result mimicked by blockade of ceramidase enzyme using ceranib‐1, which also decreased CFTR function. The SMase‐mediated inhibitory mechanism did not involve the reduction of cellular CFTR abundance or removal of CFTR from the apical surface, nor did it involve the activation of 5′ adenosine monophosphate‐activated protein kinase. In order to determine the pathological relevance of these sphingolipid imbalances, we evaluated the sphingolipid profiles of cfHBEs and cfHNEs (nasal) as compared to non‐CF controls. Sphingomyelins, ceramides, and dihydroceramides were largely increased in CF cells. Correction of ΔF508‐CFTR trafficking with VX445 + VX661 decreased some sphingomyelins and all ceramides, but exacerbated increases in dihydroceramides. Additional treatment with the CFTR potentiator VX770 did not affect these changes, suggesting rescue of misfolded CFTR was sufficient. We furthermore determined that cfHBEs express more acid‐SMase protein than nHBEs. Lastly, we determined that airway‐like neutrophils, which are increased in the CF lung, secrete acid‐SMase. Identifying the mechanism of SMase‐mediated inhibition of CFTR will be important, given the imbalance of sphingolipids in CF cells and the secretion of acid‐SMase from cell types relevant to CF. [ABSTRACT FROM AUTHOR]

Cardiomyocytes autophagy is essential for maintaining cardiac function. Our previous studies have found that β1‐adrenergic receptor autoantibody (β1‐AA) induced the decreased myocardial autophagic flux, which resulted in cardiomyocyte death and cardiac dysfunction. And other studies demonstrated that β1‐AA induced the decrease of AMPK phosphorylation, the key hub of autophagy pathway, while adiponectin up‐regulated autophagic flux mediated by AMPK. However, it is not clear whether adiponectin improves the inhibition of myocardial autophagic flux induced by β1‐AA by up‐regulating the level of AMPK phosphorylation. In this study, it has been confirmed that β1‐AA induced the decrease of AMPK phosphorylation level in both vivo and vitro. Moreover, pretreatment of cardiomyocytes with AMPK inhibitor Compound C could further reduce the autophagic flux induced by β1‐AA. Adiponectin deficiency could aggravate the decrease of myocardial AMPK phosphorylation level, autophagic flux and cardiac function induced by β1‐AA. Further, exogenous adiponectin could reverse the decline of AMPK phosphorylation level and autophagic flux induced by β1‐AA and even reduce cardiomyocyte death. While pretreated with the Compound C, the adiponectin treatment did not improve the decreased autophagosome formation, but still improved the decreased autophagosome clearance induced by β1‐AA in cardiomyocytes. This study is the first time to confirm that β1‐AA could inhibit myocardial autophagic flux by down‐regulating AMPK phosphorylation level. Adiponectin could improve the inhibition of myocardial autophagic flux induced by β1‐AA partly dependent on AMPK, so as to provide an experimental basis for the treatment of patients with β1‐AA‐positive cardiac dysfunction. [ABSTRACT FROM AUTHOR]

The involvement of long non‐coding RNAs (lncRNAs), differentially expressed genes and signals in prostate cancer (PCa) continues to be a subject of investigation. This study determined effects of LOC100996425 on human PCa by targeting hepatocyte nuclear factor 4A (HNF4A) via the AMPK/mTOR pathway. PCa and adjacent normal tissues were obtained to characterize expression pattern of LOC100996425, HNF4A and the AMPK/mTOR pathway‐related genes. Then, the target gene of LOC100996425 was determined with lncRNA target prediction website and further verification was obtained through luciferase assay and ribonucleoprotein immunoprecipitation. After that, PCa cells were introduced with LOC100996425, HNF4A, siLOC100996425 or siHNF4A to explore the specific significance of LOC100996425 and HNF4A in PCa. The mechanism associated with AMPK/mTOR pathway was investigated using AMPK inhibitor or activator. LOC100996425 was up‐regulated, while HNF4A was down‐regulated in the PCa tissues. HNF4A was a target gene of LOC100996425. PCa cells transfected with either siLOC100996425 or HNF4A displayed reduced rates of PCa cell proliferation and migration while elevating cell apoptosis. HNF4A overexpression reversed the promotive effect of LOC100996425 overexpression on PCa. The activation of AMPK pathway involved in the cancer progression mediated by LOC100996425. Down‐regulation of LOC100996425 retards progression of PCa through HNF4A‐mediated AMPK/mTOR pathway. [ABSTRACT FROM AUTHOR]

Vismodegib, a Smoothened antagonist, is clinically approved for treatment of human basal cell carcinoma (BCC), in the clinical trials of medulloblastoma (MB) and other cancers. However, a significant proportion of these tumors fail to respond to Vismodegib after a period of treatment. Here, we find that AMPK agonists, A769662, and Metformin, can inhibit GLI1 activity and synergize with Vismodegib to suppress MB cell growth invitro and invivo. Furthermore, combination of AMPK agonists with Vismodegib is effective in overcoming Vismodegib‐resistant MB. This is the first report demonstrating that combining AMPK agonist (Metformin) and SHH pathway inhibitor (Vismodegib) confers synergy for MB treatment and provides an effective chemotherapeutic regimen that can be used to overcome resistance to Vismodegib in SHH‐driven cancers. [ABSTRACT FROM AUTHOR]

Background: The direct correlation between Sertoli cell number and sperm production capacity highlights the importance of deciphering external factors that modify Sertoli cell proliferation. A growing body of evidence in vitro suggests that metformin, the main pharmacological agent for type 2 diabetes treatment in children, exerts anti‐proliferative effects on Sertoli cells. Objective: The aims of this study were to investigate the effect of metformin administration during postnatal period on Sertoli cell proliferation and on cell cycle regulators expression and to analyze the impact of this treatment on the sperm production capacity in adulthood. Materials and Methods: Sprague Dawley rat pups were randomly divided into two groups: MET (receiving daily 200 mg/kg metformin, from Pnd3 to Pnd7 inclusive) and control (receiving vehicle). BrdU incorporation was measured to assess proliferation. Gene expression analyses were performed in Sertoli cells isolated from animals of both groups. Daily sperm production and sperm parameters were measured in adult male rats (Pnd90) that received neonatal treatment. Results: MET group exhibited a significant decrease in BrdU incorporation in Sertoli cells. Concordantly, MET group showed a reduction in cyclin D1 and E2 expression and an increase in p21 expression in Sertoli cells. In addition, metformin‐treated animals displayed lower values of daily sperm production on Pnd90. Discussion and Conclusion: These results suggest that metformin treatment may lead to a decrease in Sertoli cell proliferation, a concomitant altered expression of cell cycle regulators and ultimately, a reduction in daily sperm production in adult animals. [ABSTRACT FROM AUTHOR]

Aims: In patients with renal disease, high serum phosphate shows a relationship with cardiovascular risk. We speculate that high phosphate (HP) impairs arterial vasodilation via the endothelium and explore potential underlying mechanisms. Methods: Isolated vessel relaxation, endothelial function, glomerular filtration rate (GFR), oxidative stress status and protein expression were assessed in HP diet mice. Mitochondrial function and protein expression were assessed in HP‐treated human umbilical vein endothelial cells (HUVECs). Results: High phosphate (1.3%) diet for 12 weeks impaired endothelium‐dependent relaxation in mesenteric arteries, kidney interlobar arteries and afferent arterioles; reduced GFR and the blood pressure responses to acute administration of acetylcholine. The PPARα/LKB1/AMPK/eNOS pathway was attenuated in the endothelium of mesenteric arteries from HP diet mice. The observed vasodilatory impairment of mesenteric arteries was ameliorated by PPARα agonist WY‐14643. The phosphate transporter PiT‐1 knockdown prevented HP‐mediated suppression of eNOS activity by impeding phosphorus influx in HUVECs. Endothelium cytoplasmic and mitochondrial reactive oxygen species (ROS) were increased in HP diet mice. Moreover HP decreased the expression of mitochondrial‐related antioxidant genes. Finally, mitochondrial membrane potential and PGC‐1α expression were reduced by HP treatment in HUVECs, which was partly restored by AMPKα agonist. Conclusions: HP impairs endothelial function by reducing NO bioavailability via decreasing eNOS activity and increasing mitochondrial ROS, in which the AMPK‐related signalling pathways may play a key role. [ABSTRACT FROM AUTHOR]

Salsalate, an ester formed by 2 salicylic acid molecules, has beneficial effect against metabolic disorders in clinical trials and in animal studies. This study focused on the mechanistic aspects of salsalate activity against non‐alcoholic fatty liver disease (NAFLD). Using high‐fat diet (HFD) fed mice, we showed that salsalate treatment decreased body‐weight gains, reduced white adipose tissue mass and improved glycaemic control. Mice in salsalate‐treated group also had reduced obese adipose tissue and hepatic macrophage infiltration and inflammation and adipogenesis gene expression. Histology analysis revealed predominant decreases in hepatosteatosis, including both macrovesicular and microvesicular steatoses. The treatment reversed AMPK activity repression that was accompanied by reduced caspase‐6 activity and cleavage. Enzymatic assay and cell culture studies showed that salsalate promoted AMPK activation by directly activating AMPK. This study links salsalate effect against metabolic disorders to its activity on reversion of AMPK repression in NAFLD mice and on suppression of adipogenic gene induction. [ABSTRACT FROM AUTHOR]

The past decade has witnessed growing scientific and commercial interest in the identification of bioactive oral compounds that mimic or potentiate the effects of exercise, so‐called 'exercise pills' or 'exercise mimetics.' These compounds have, to date, typically targeted skeletal muscle in an attempt to stimulate some of the adaptations to exercise induced by endurance training. Accordingly, they fail to impart many of the broad health protecting effects of exercise that are seen in tissues and organs other than skeletal muscle. In the context that multiple integrative regulatory and often redundant pathways have evolved to detect and respond to human movement, here we consider the complex challenges of designing a pill that might mimic the extensive range of exercise benefits. In particular, we consider the limits of the current 'myocentric' paradigm given the wide‐ranging array of impacts that exercise exerts on atherosclerosis and the cardiovascular system. We discuss the validity and limitations of the concept that low dose cardiovascular polypills, already in large scale trials, may represent one form of cardiovascular exercise mimetic. Finally, given that some calls for an exercise pill stem from a response to the perceived failure of expert advice, evidence‐based guidelines and current public health approaches, we explore possible strategies that might address the global rise in inactivity. In the event that a broad spectrum exercise mimetic might ever be developed, we discuss some generic issues related to adoption and adherence of therapeutic interventions. [ABSTRACT FROM AUTHOR]

The efficacy of bleomycin (BLM) as an antineoplastic drug is limited to the development of dose and time‐dependent pulmonary fibrosis. This study was intended to investigate the effect of N‐acetylcysteine (NAC) on BLM‐induced pulmonary fibrosis in rats. Twenty rats were randomly divided to the following four groups: Group one served as control; group two received BLM (15 mg/kg, intraperitoneal (ip)) for five consecutive days; group three received NAC (200 mg/kg, ip) for five consecutive days; and group four received NAC 1 hour before BLM for 5 days. The expression of connective tissue growth factor (CTGF), platelet‐derived growth factor (PDGF), silent information regulator l (SIRT1), AMP‐activated protein kinase (AMPK) were determined by qRT‐PCR in lung tissues. The changes in transforming growth factor‐beta1 (TGF‐β1), tumour necrosis factor‐α (TNF‐α), interleukin‐β1 (IL‐β1) and nuclear factor kappa‐β (NF‐κβ) in serum were measured by ELISA. The tissue antioxidant status was determined biochemically. BLM administration caused pulmonary fibrosis as evidenced by increased levels of inflammatory mediators (TGF‐β1, TNF‐α, IL‐β1 and NF‐κβ) in serum (P <.05), elevated lipid peroxidation and nitric oxide and depleted endogenous antioxidants in lung tissue (P <.05). The expression levels of SIRT1 and AMPK were significantly decreased (P <.05), while the expression levels of CTGF and PDGF were increased significantly in the BLM group as compared to the control group (P <.05). These alterations were normalized by NAC intervention. NAC markedly attenuated the lung histopathological changes and reduced collagen deposition. These results suggest that NAC exerted an ameliorative effect against BLM‐induced oxidative damage and pulmonary fibrosis via SIRT1/ AMPK/ NF‐κβ pathways. [ABSTRACT FROM AUTHOR]

Cockayne syndrome (CS) is a rare premature aging disease, most commonly caused by mutations of the genes encoding the CSA or CSB proteins. CS patients display cachectic dwarfism and severe neurological manifestations and have an average life expectancy of 12 years. The CS proteins are involved in transcription and DNA repair, with the latter including transcription‐coupled nucleotide excision repair (TC‐NER). However, there is also evidence for mitochondrial dysfunction in CS, which likely contributes to the severe premature aging phenotype of this disease. While damaged mitochondria and impaired mitophagy were characterized in mice with CSB deficiency, such changes in the CS nematode model and CS patients are not fully known. Our cross‐species transcriptomic analysis in CS postmortem brain tissue, CS mouse, and nematode models shows that mitochondrial dysfunction is indeed a common feature in CS. Restoration of mitochondrial dysfunction through NAD+ supplementation significantly improved lifespan and healthspan in the CS nematodes, highlighting mitochondrial dysfunction as a major driver of the aging features of CS. In cerebellar samples from CS patients, we found molecular signatures of dysfunctional mitochondrial dynamics and impaired mitophagy/autophagy. In primary cells depleted for CSA or CSB, this dysfunction can be corrected with supplementation of NAD+ precursors. Our study provides support for the interconnection between major causative aging theories, DNA damage accumulation, mitochondrial dysfunction, and compromised mitophagy/autophagy. Together, these three agents contribute to an accelerated aging program that can be averted by cellular NAD+ restoration. [ABSTRACT FROM AUTHOR]

Osteoclasts are multinucleated giant cells, responsible for bone resorption. Osteoclast differentiation and function requires a series of cytokines to remove the old bone, which coordinates with the induction of bone remodelling by osteoblast‐mediated bone formation. Studies have demonstrated that AMP‐activated protein kinase (AMPK) play a negative regulatory role in osteoclast differentiation and function. Research involving AMPK, a nutrient and energy sensor, has primarily focused on osteoclast differentiation and function; thus, its role in autophagy, inflammation and immunity remains poorly understood. Autophagy is a conservative homoeostatic mechanism of eukaryotic cells, and response to osteoclast differentiation and function; however, how it interacts with inflammation remains unclear. Additionally, based on the regulatory function of different AMPK subunits for osteoclast differentiation and function, its activation is regulated by upstream factors to perform bone metabolism. This review summarises the critical role of AMPK‐mediated autophagy, inflammation and immunity by upstream and downstream signalling during receptor activator of nuclear factor kappa‐B ligand‐induced osteoclast differentiation and function. This pathway may provide therapeutic targets for bone‐related diseases, as well as function as a biomarker for bone homoeostasis. [ABSTRACT FROM AUTHOR]

Objective: Cardiovascular diseases and vascular aging are common in patients with diabetes. High glucose is a major cause of vascular aging and cardiovascular diseases. Premature senescence of vascular smooth muscle cells (VSMCs) is one of the main contributors to vascular aging. Adiponectin has been demonstrated to have an anti‐aging effect. The present study explored the mechanisms by which adiponectin protects VSMCs against high‐glucose‐induced senescence. Methods: Senescence‐associated β‐galactosidase (SA‐β‐gal) staining was used to detect senescence cells. Western blot was used for measuring protein levels. Flow cytometry was carried out to detect the cell cycle and telomeric repeat amplification protocol (TRAP)–polymerase chain reaction (PCR) silver staining was selected to measure the telomerase activity. Results: Premature senescence of VSMCs was induced by high glucose (30 mM) in a time‐dependent manner, which was verified by an increased number of senescence cells, p21 and p53 expression, as well as the decreased proliferation index. High glucose reduced telomerase activity of VSMCs via inhibition of the AMPK/TSC2/mTOR/S6K1 pathway and activation of the PI3K/Akt/mTOR/S6K1 pathway, while adiponectin treatment significantly increased telomerase activity of VSMCs through activation of AMPK/TSC2/mTOR/S6K1 signaling and inhibition of PI3K/Akt/mTOR/S6K1 signaling. Conclusion: Adiponectin attenuated the high‐glucose‐induced premature senescence of VSMCs via increasing telomerase activity of VSMCs, which was achieved by activation of AMPK/TSC2/mTOR/S6K1 signaling and inhibition of PI3K/Akt/mTOR/S6K1 signaling. [ABSTRACT FROM AUTHOR]

Obesity is a leading cause of preventable death worldwide. Despite this, current strategies for the treatment of obesity remain ineffective at achieving long‐term weight control. This is due, in part, to difficulties in identifying tolerable and efficacious small molecules or biologics capable of regulating systemic nutrient homeostasis. Here, we demonstrate that BAM15, a mitochondrially targeted small molecule protonophore, stimulates energy expenditure and glucose and lipid metabolism to protect against diet‐induced obesity. Exposure to BAM15 in vitro enhanced mitochondrial respiratory kinetics, improved insulin action, and stimulated nutrient uptake by sustained activation of AMPK. C57BL/6J mice treated with BAM15 were resistant to weight gain. Furthermore, BAM15‐treated mice exhibited improved body composition and glycemic control independent of weight loss, effects attributable to drug targeting of lipid‐rich tissues. We provide the first phenotypic characterization and demonstration of pre‐clinical efficacy for BAM15 as a pharmacological approach for the treatment of obesity and related diseases. Synopsis: This study presents a novel therapy for treatment of obesity‐related diseases. Oral delivery of the mitochondrial protonophore BAM15 markedly reduced weight gain and fat accrual while improving glycemic control. BAM15 displays extended mitochondrial activity compared to previous generation protonophores.BAM15 protects against diet induced obesity.BAM15 modulates body composition and glycemic control independently of its weight‐reducing effects.AMPK is required to sustain the metabolic benefit of BAM15, which occurs primarily in adipose tissue. [ABSTRACT FROM AUTHOR]

Key points: AMP‐activated protein kinase (AMPK)‐dependent Raptor Ser792 phosphorylation does not influence mechanistic target of rapamycin complex 1 (mTORC1)‐S6K1 activation by intense muscle contraction.α2‐AMPK activity‐deficient mice have lower contraction‐stimulated protein synthesis.Increasing glycogen activates mTORC1‐S6K1.Normalizing muscle glycogen content rescues reduced protein synthesis in AMPK‐deficient mice. The mechansitic target of rapamycin complex 1 (mTORC1)‐S6K1 signalling pathway regulates muscle growth‐related protein synthesis and is antagonized by AMP‐activated protein kinase (AMPK) in multiple cell types. Resistance exercise stimulates skeletal muscle mTORC1‐S6K1 and AMPK signalling and post‐contraction protein synthesis. Glycogen inhibits AMPK and has been proposed as a pro‐anabolic stimulus. The present study aimed to investigate how muscle mTORC1‐S6K1 signalling and protein synthesis respond to resistance exercise‐mimicking contraction in the absence of AMPK and with glycogen manipulation. Resistance exercise‐mimicking unilateral in situ contraction of musculus quadriceps femoris in anaesthetized wild‐type and dominant negative α2 AMPK kinase dead transgenic (KD‐AMPK) mice, measuring muscle mTORC1 and AMPK signalling immediately (0 h) and 4 h post‐contraction, and protein‐synthesis at 4 h. Muscle glycogen manipulation by 5 day oral gavage of the glycogen phosphorylase inhibitor CP316819 and sucrose (80 g L−1) in the drinking water prior to in situ contraction. The mTORC1‐S6K1 and AMPK signalling axes were coactivated immediately post‐contraction, despite potent AMPK‐dependent Ser792 phosphorylation on the mTORC1 subunit raptor. KD‐AMPK muscles displayed normal mTORC1‐S6K1 activation at 0 h and 4 h post‐exercise, although there was impaired contraction‐stimulated protein synthesis 4 h post‐contraction. Pharmacological/dietary elevation of muscle glycogen content augmented contraction‐stimulated mTORC1‐S6K1‐S6 signalling and rescued the reduced protein synthesis‐response in KD‐AMPK to wild‐type levels. mTORC‐S6K1 signalling is not influenced by α2‐AMPK during or after intense muscle contraction. Elevated glycogen augments mTORC1‐S6K1 signalling. α2‐AMPK‐deficient KD‐AMPK mice display impaired contraction‐induced muscle protein synthesis, which can be rescued by normalizing muscle glycogen content. Key points: AMP‐activated protein kinase (AMPK)‐dependent Raptor Ser792 phosphorylation does not influence mechanistic target of rapamycin complex 1 (mTORC1)‐S6K1 activation by intense muscle contraction.α2‐AMPK activity‐deficient mice have lower contraction‐stimulated protein synthesis.Increasing glycogen activates mTORC1‐S6K1.Normalizing muscle glycogen content rescues reduced protein synthesis in AMPK‐deficient mice. [ABSTRACT FROM AUTHOR]

Cardiovascular diseases such as myocardial ischaemia have a high fatality rate in patients with diabetes. This study was designed to expose the crosstalk between oxidative stress and AMPK, a vital molecule that controls biological energy metabolism, in myocardial ischaemia reperfusion injury (I/RI) in diabetic rats. Diabetes was stimulated in rats using streptozotocin injection. Rats were separated on random into control, control + I/R, Diabetes, Diabetes + I/R, Diabetes + I/R + N‐acetylcysteine and Diabetes + I/R + Vas2870 groups. Myocardial infarct size was determined, and the predominant Nox family isoforms were analysed. In vitro, the H9C2 cells were administered excess glucose and exposed to hypoxia/reoxygenation to mimic diabetes and I/R. The AMPK siRNA or AICAR was used to inhibit or activate AMPK expression in H9C2 cells, respectively. Then, myocardial oxidative stress and programmed cell death were measured. Diabetes or high glucose levels were found to aggravate myocardial I/RI or hypoxia/reoxygenation in H9C2 cells, as demonstrated by an increase in myocardial infarct size or lactate dehydrogenase levels, oxidative stress generation and induction of programmed cell death. In diabetic rat hearts, cardiac Nox1, Nox2 and Nox4 were all heightened. The suppression of Nox2 expression using Vas2870 or Nox2‐siRNA treatment in vivo or in vitro, respectively, protected diabetic rats from myocardial I/RI. AMPK gene knockout increased Nox2 protein expression while AMPK agonist decreased Nox2 expression. Therefore, diabetes aggravates myocardial I/RI by generating of Nox2‐associated oxidative stress in an AMPK‐dependent manner, which led to the induction of programmed cell death such as apoptosis, pyroptosis and ferroptosis. [ABSTRACT FROM AUTHOR]

This trial evaluated the potential impacts of saffron aqueous extract (SAE) and its main carotenoid on some of the atherosclerosis-related gene expression and serum levels of oxidized low-density cholesterol (ox-LDL) and Monocyte chemoattractant protein 1 (MCP-1) in patients with coronary artery disease (CAD). Participants of this randomized controlled trial included 84 CAD patients who categorized into three groups: Group 1 received crocin (30 mg/day), Group 2 SAE (30 mg/day), and Group 3 placebo for 8 weeks. Gene expression of Sirtuin 1 (SIRT1), 5'-adenosine monophosphate-activated protein kinase (AMPK), Lectin-like oxidized LDL receptor 1 (LOX1), nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), and MCP-1 in peripheral blood mononuclear cells assessed by real-time PCR. Furthermore, serum ox-LDL and MCP-1 levels measured at the beginning and end of the intervention. Compared with the placebo group, gene expression of SIRT1 and AMPK increased significantly in the crocin group (p = .001), and the expression of LOX1 and NF-κB decreased significantly (p = .016 and .004, respectively). Serum ox-LDL levels decreased significantly in the crocin group after the intervention (p = .002) while MCP-1 levels decreased both in crocin and SAE groups (p = .001). Crocin may have beneficial effects on CAD patients by increasing the gene expression of SIRT1 and AMPK and decreasing the expression of LOX1 and NF-κB. [ABSTRACT FROM AUTHOR]

Chicoric acid is polyphenol of natural plant and has a variety of bioactivity. Caused by various kinds of stimulating factors, acute liver injury has high fatality rate. The effect of chicoric acid in acute liver injury induced by Lipopolysaccharide (LPS) and d‐galactosamine (d‐GalN) was investigated in this study. The results showed that CA decreased the aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in serum and reduced the mortality induced by LPS/d‐GalN. CA can restrain mitogen‐activated protein kinases (MAPKs) and nuclear factor‐kappa B (NF‐κB) to alleviate inflammation. Meanwhile, the results indicated CA can active nuclear factor‐erythroid 2‐related factor 2 (Nrf2) pathway with increasing the level of AMP‐activated protein kinase (AMPK). And with the treatment of CA, protein levels of autophagy genes were obvious improved. The results of experiments indicate that CA has protective effect in liver injury, and the activation of AMPK and autophagy may make sense. [ABSTRACT FROM AUTHOR]

Gallbladder cancer (GBC) is the leading malignancy of biliary system showing refractory chemoresistance to current first‐line drugs. Growing epidemiological evidences have established that the incidence of GBC exhibits significant gender predominance with females two‐threefold higher than males, suggesting oestrogen/oestrogen receptors (ERs) signalling might be a critical driver of tumorigenesis in gallbladder. This study aims to evaluate the antitumour activity of tamoxifen (TAM), a major agent of hormonal therapy for breast cancer, in preclinical GBC model. Quantitative real‐time PCR was used to investigate mRNA levels. Protein expression was measured by immunohistochemistry and Western blot. Glycolytic levels were measured by glucose consumption and lactic acid measurement. The antitumour activity of TAM alone or with cisplatin was examined with CCK8 assay, colony formation, flow cytometry and in vivo models. The results revealed that ERɑ expression was higher in GBC tissues and predicted poor clinical outcomes. TAM was showed effective against a variety of GBC cell lines. Mechanical investigations revealed that TAM enabled potent reactive oxygen species (ROS) production by reduced nuclear factor Nrf2 expression and its target genes, leading to the activation of AMPK, which subsequently induced impaired glycolysis and survival advantages. Notably, TAM was demonstrated to sensitize GBC cells to cisplatin (CDDP) both in vitro and in vivo. In agreement with these findings, elimination of oestrogens by ovariectomy in nude mice prevented CDDP resistance. In summary, these results provide basis for TAM treatment for GBC and shed novel light on the potential application of endocrine therapy for patients with GBC. [ABSTRACT FROM AUTHOR]

High rates of de novo lipid synthesis have been discovered in certain kinds of tumours, including gallbladder cancer (GBC). Unlike several other tumours, GBC is highly insensitive to standard adjuvant therapy, which makes its treatment even more challenging. Although several potential targets and signalling pathways underlying GBC chemoresistance have been revealed, the precise mechanisms are still elusive. In this study, we found that α‐Mangostin, as a dietary xanthone, repressed the proliferation and clone formation ability, induced cell cycle arrest and the apoptosis, and suppressed de novo lipogenesis of gallbladder cancer cells. The underlying mechanisms might involve the activation of AMPK and, therefore, the suppression of SREBP1 nuclear translocation to blunt de novo lipogenesis. Furthermore, SREBP1 silencing by siRNA or α‐mangostin enhanced the sensitivity of gemcitabine in gallbladder cancer cells. In vivo studies also displayed that MA or gemcitabine administration to nude mice harbouring NOZ tumours can reduce tumour growth, and moreover, MA administration can significantly potentiate gemcitabine‐induced inhibition of tumour growth. Corroborating in vitro findings, tumours from mice treated with MA or gemcitabine alone showed decreased levels of proliferation with reduced Ki‐67 expression and elevated apoptosis confirmed by TUNEL staining, furthermore, the proliferation inhibition and apoptosis up‐regulation were obviously observed in MA combined with gemcitabine treatment group. Therefore, inhibiting de novo lipogenesis via targeting the AMPK/SREBP1 signalling by MA might provide insights into a potential strategy for sensitizing GBC cells to chemotherapy. [ABSTRACT FROM AUTHOR]

Purpose: Cannabinoids have been shown to exert analgesic and anti‐inflammatory effects, and the effects of cannabinoids are mediated primarily by cannabinoid receptors 1 and 2 (CB1 and CB2). The objective of this study was to determine efficacy and mechanism of CB2 activation on cyclophosphamide (CYP)‐induced cystitis in vivo. Methods: Cystitis was induced by intraperitoneal (IP) injection of CYP in female C57BL/6J mice. Mice were pretreated with CB2 agonist JWH‐133 (1 mg/kg, intraperitoneally), CB2 antagonist AM‐630 (1 mg/kg, intraperitoneally) or autophagy inhibitor 3‐methyladenine (3‐MA) (50 mM, intraperitoneally) before IP injection of CYP. Peripheral nociception and spontaneous voiding were investigated in these mice. Bladders were collected, weighed, and processed for real‐time polymerase chain reaction, immunoblotting analysis, histological and immunohistochemical analysis. Results: Twenty‐four hours after IP injection of CYP, the bladder of CYP‐treated mice showed histological evidence of inflammation. The expression of CB2 in bladder was significantly increased in CYP‐treated mice. Mechanical sensitivity was significantly increased in CYP‐treated mice and CB2 agonist JWH‐133 attenuated this effect (P <.05). The number of urine spots was significantly increased after CYP treatment and it was decreased in JWH‐133 treated mice (P <.05). Activating CB2 with JWH‐133 significantly alleviated bladder tissue inflammatory responses and oxidative stress induced by CYP. Activation of CB2 by JWH‐133 increased the expression of LC3‐II/LC3‐I ratio, and decreased the expression of SQSTM1/p62 in the bladder of cystitis mice, whereas AM‐630 induced inverse effects. Further study indicated that JWH‐133 could promote autophagy and blocking autophagy by 3‐MA dismissed the effort of CB2 in alleviating bladder tissue inflammatory responses and oxidative stress injury. Furthermore, treatment with 3‐MA decreased the expression of p‐AMPK and induced the phosphorylation of mTOR in the presence of JWH‐133 stimulation in cystitis model. Conclusions: Activation of CB2 decreased severity of CYP‐induced cystitis and ameliorated bladder inflammation. CB2 activation is protective in cystitis through the activation of autophagy and AMPK‐mTOR pathway may be involved in the initiation of autophagy. [ABSTRACT FROM AUTHOR]

The article focuses on inhibition of migration of tongue squamous cell carcinoma (TSCC) cells by 5-aminoimidazole-4-carboxamide riboside (AICAR) induced AMP-activated protein kinase (AMPK). Topics include the damage to the tight junctions (TJ) structure through an abnormal increase and redistribution of ZO-1 and ZO-1/cofilin-mediated de-polymerization of F-actin.

The anhydrobiotic tardigrade, Hypsibius exemplaris, was previously considered to require de novo gene expression and protein phosphatase 1 (PP1) and protein phosphatase 2A (PP2A) activity for successful anhydrobiosis. These indicate that H. exemplaris has signal transduction systems responding to desiccation stress, with the involvement of phosphorylation events. To this end, we carried out time‐series phosphoproteomics of H. exemplaris exposed to mild desiccation stress and detected 48 phosphoproteins with significant differential regulations. Among them, immediate and successive reduction of phosphorylation levels of AMP‐activated protein kinase (AMPK) was observed. The subsequent chemical genetic approach showed that AMPK was activated during the preconditioning stage for anhydrobiosis, and inhibition of its activity impaired successful anhydrobiosis. As PP2A is known to dephosphorylate AMPK in other organisms, we suggested that decreased phosphorylation levels of AMPK upon mild desiccation stress were caused by dephosphorylation by PP2A. Accordingly, phosphoproteomics of animals pre‐treated with the PP1/PP2A inhibitor cantharidic acid (CA) lacked the decrease in phosphorylation levels of AMPK. These observations suggest that AMPK activity is required for successful anhydrobiosis in H. exemplaris, and its phosphorylation state is possibly regulated by PP2A. [ABSTRACT FROM AUTHOR]

Diabetes affects a large population of the world. Lifestyle, obesity, dietary habits, and genetic factors contribute to this metabolic disease. A target pathway to control diabetes is the 5′‐adenosine monophosphate‐activated protein kinase (AMPK) signaling pathway. AMPK is a heterotrimeric protein with α, β, and γ subunits. In several studies, AMPK activation enhanced glucose uptake into cells and inhibited intracellular glucose production. Impairment of AMPK activity is present in diabetes, according to some studies. Drugs used in the treatment of diabetes, such as metformin, are also known to act through regulation of AMPK. Thus, drugs that activate and regulate AMPK are potential candidates for the treatment of diabetes. In addition, many patients encounter important adverse effects, like hypoglycemia, while using allopathic drugs. As a result, the investigation of plant‐derived natural drugs that lack adverse side effects and treat diabetes is necessary. Natural products like berberine, quercetin, resveratrol, and so forth have shown significant potential in regulating and activating the AMPK pathway which can lead to manage diabetes mellitus and its complications. [ABSTRACT FROM AUTHOR]

The role as well as the molecular mechanisms of protectin DX (PDX) in the prevention of hepatic insulin resistance, a hallmark of type 2 diabetes, remains unknown. Therefore, the present study was designed to explore the direct impact of PDX on insulin resistance and to investigate the expression of fetuin‐A and selenoprotein P (SeP), hepatokines that are involved in insulin signalling, in hepatocytes. Human serum levels of PDX as well as fetuin‐A and SeP were determined by high‐performance liquid chromatography (HPLC). Human primary hepatocytes were treated with palmitate and PDX. NF‐κB phosphorylation as well as expression of insulin signalling associated genes and hepatokines were determined by Western blotting analysis. FOXO1 binding levels were measured by quantitative real‐time PCR. Selected genes from candidate pathways were evaluated by small interfering (si) RNA‐mediated gene suppression. Serum PDX levels were significantly (P < 0.05) downregulated, whereas serum fetuin‐A and SeP levels were increased (P < 0.05) in obese subjects compared with healthy subjects. In in vitro experiments, PDX treatment increased AMP‐activated protein kinase (AMPK) phosphorylation and SIRT1 expression and attenuated palmitate‐induced fetuin‐A and SeP expression and insulin resistance in hepatocytes. AMPK or SIRT1 siRNA mitigated the suppressive effects of PDX on palmitate‐induced fetuin‐A through NF‐κB and SeP expression linked to FOXO1 and insulin resistance. Recombinant fetuin‐A and SeP reversed the suppressive effects of fetuin‐A and SeP expression on palmitate‐mediated impairment of insulin signalling. The current finding provides novel insight into the underlying mechanism linking hepatokines to the pathogenesis of hepatic insulin resistance. [ABSTRACT FROM AUTHOR]

Cementum, which shares common features with bone in terms of biochemical composition, is important for the homeostasis of periodontium during periodontitis and orthodontic treatment. Sirtuin 6 (SIRT6), as a member of the sirtuin family, plays key roles in the osteogenic differentiation of bone marrow mesenchymal stem cells. However, the involvement of SIRT6 in cementoblast differentiation and mineralization and the underlying mechanisms remain unknown. In this study, we observed that the expression of SIRT6 increased during cementoblast differentiation initially. Analysis of the gain‐ and loss‐of‐function indicated that overexpressing SIRT6 in OCCM‐30 cells suppresses cementoblast differentiation and mineralization and downregulating SIRT6 promotes cementogenesis. GLUT1, a glucose transporter necessary in cementogenesis, was inhibited by SIRT6. Overexpressing GLUT1 in SIRT6‐overexpressed OCCM‐30 cells rescued the inhibitory effect of SIRT6 on cementoblast differentiation and mineralization. Moreover, AMPK was activated after overexpressing SIRT6 and inhibited cementoblast differentiation and mineralization. Downregulating the expression of SIRT6 inhibited AMPK activity. Meanwhile, GLUT1 overexpression significantly decreased AMPK activity. Overall, on one hand, SIRT6 inhibited cementoblast differentiation and mineralization by suppressing GLUT1. On the other hand, SIRT6 inhibited cementoblast differentiation and mineralization by activating the AMPK pathway. GLUT1 overexpression also rescued the increased AMPK pathway activated by SIRT6. SIRT6 inhibited cementoblast differentiation and mineralization by suppressing GLUT1. AMPK pathway also participated in SIRT6 regulated cementogenesis. [ABSTRACT FROM AUTHOR]

Recent studies have been trying to find out how diet and metabolic changes such as dyslipidaemia, hyperglycaemia, and hyperinsulinaemia can stimulate cancer progression. This investigation aimed to evaluate the effect of high concentrations of fatty acids and/or glucose in tumour prostate cells, focusing on the proliferation/migration profile and oxidative stress. PC3 cells were treated with high concentration of saturated fatty acid (palmitate, 100 µM), glucose (220 mg/dL), or both for 24 or 48 h. Results demonstrated that PC3 cells showed a significant increase in proliferation after 48 h of treatment with glucose and palmitate+glucose. Cell proliferation was associated with reduced levels of AMPK phosphorylation in glucose group at 24 and 48 h of treatment, while palmitate group presented this result only after 48 h of treatment. Also, there was a significant increase in cell migration between time 0 and 48 h after all treatments, except in the control. Catalase activity was increased by palmitate in the beginning of treatment, while glucose presented a later effect. Also, nitrite production was increased by glucose only after 48 h, and the total antioxidant activity was enhanced by palmitate in the initial hours. Thus, we conclude that the high concentration of the saturated fatty acid palmitate and glucose in vitro influences PC3 cells and stimulates cellular activities related to carcinogenesis such as cell proliferation, migration, and oxidative stress in different ways. Palmitate presents a rapid and initial effect, while a glucose environment stimulates cells later on, maintaining high levels of cell proliferation. [ABSTRACT FROM AUTHOR]

Steroid‐insensitive asthma‐related airway inflammation is associated with the expression of epidermal growth factor receptor (EGFR) tyrosine kinase in asthmatic bronchial epithelium. Proinflammatory cytokines IL‐6 and IL‐8 are related to steroid‐insensitive asthma. It is currently unknown how EGFR‐tyrosine kinase inhibitors (EGFR‐TKIs) affects house dust mite (HDM)‐induced asthma in terms of inflammatory cytokines related to steroid‐resistant asthma and further signaling pathway. Cytokine expressions and EGFR signaling pathway were performed by ELISA, reverse transcriptase PCR, real‐time PCR, and Western blot in cell‐line models. AMP‐activated protein kinase (AMPK) pathway‐related inhibitors were applied to confirm the association between EGFR‐TKI and AMPK pathway. HDM induced IL‐6 and IL‐8 in a dose‐dependent manner. Both Erlotinib (Tarceva) and Osimertinib (AZD‐9291) reduced the levels of HDM‐stimulated IL‐6 and IL‐8 levels in BEAS‐2B cells. AZD‐9291 was more effective than Erlotinib in inhibiting phospho‐EGFR, and downstream phosphatidylinositol‐3‐kinase/protein kinase B (PI3K/AKT) and phopho‐signal transducer and activator of transcription 3 (p‐STAT3) pathway signaling. In addition, AMPK pathway‐related inhibitor, Calcium‐/calmodulin‐dependent protein kinase kinase β (CaMKKβ) inhibitor, down‐regulated IL‐8, but EGFR‐TKI had no effect on AMPK pathway. Our findings highlight EGFR‐TKIs, Tarceva, and AZD‐9291, attenuate HDM‐induced inflammatory IL‐6 and IL‐8 cytokines via EGFR signaling axis pathway, but not AMPK signaling pathway. [ABSTRACT FROM AUTHOR]

Several studies have shown that pharmacological concentrations of biotin decrease serum lipid concentrations and the expression of lipogenic genes. Previous studies on epididymal adipose tissue in mice revealed that 8 weeks of dietary biotin supplementation increased the protein abundance of the active form of AMPK and the inactive forms acetyl CoA carboxylase (ACC)‐1 and − 2, and decreased serum free fatty acid concentrations but did not affect lipolysis. These data suggest that pharmacological concentrations of the vitamin might affect fatty acid metabolism. In this work, we investigated the effects of pharmacological biotin concentrations on fatty acid synthesis, oxidation, and uptake in 3T3‐L1 adipocytes. Similar to observations in mice, biotin‐supplemented 3T3‐L1 adipose cells increased the protein abundance of active T172‐AMPK and inactive ACC‐1 and ‐2 forms. No changes were observed in the expression of the transcriptional factor PPARα and carnitine‐palmitoyltransferase‐1 (CPT‐1). Radiolabeled assays indicated a decrease in fatty acid synthesis; an increase in fatty acid oxidation and fatty acid incorporation rate into the lipid fraction between control cells and biotin‐supplemented cells. The data revealed an increase in the mRNA abundance of the fatty acid transport proteins Fatp1 and Acsl1 but not Cd36 or Fatp4 mRNA. Furthermore, the abundance of glycerol phosphate acyl transferase‐3 protein was increased. Triglyceride content was not affected. Lipid droplet numbers showed an increase and their areas were smaller in the biotin‐supplemented group. In conclusion, these data indicate that biotin supplementation causes a decrease in fatty acid synthesis and an increase in its oxidation and uptake. © 2018 BioFactors, 45(2):259–270, 2019 [ABSTRACT FROM AUTHOR]

Keywords: AMPK; endurance training; exercise; skeletal muscle EN AMPK endurance training exercise skeletal muscle 5017 5019 3 11/16/20 20201115 NES 201115 Since the seminal findings that pharmacological activation of AMP-activated protein kinase (AMPK) increases skeletal muscle glucose uptake and fatty acid oxidation (FAO), AMPK has gained considerable interest as a regulator of fuel utilization during exercise. Inducible deletion of skeletal muscle AMPK a reveals that AMPK is required for nucleotide balance but dispensable for muscle glucose uptake and fat oxidation during exercise. [Extracted from the article]

4‐O‐methylascochlorin (MAC) is a derivative of ascochlorin, a prenyl‐phenol compound antibiotic isolated from the fungus Ascochyta viciae. MAC induces caspase/poly (ADP‐ribose) polymerase‐mediated apoptosis in leukemia cells. However, the effects of MAC on autophagy in cancer cells and the underlying molecular mechanisms remain unknown. Here, we show that MAC induces autophagy in lung cancer cells. MAC significantly induced the expression of autophagy marker proteins including LC3‐II, Beclin1, and ATG7. MAC promoted AMP‐activated protein kinase (AMPK) phosphorylation and inhibited the phosphorylation of mammalian target of rapamycin (mTOR) and its downstream signalling proteins P70S6K and 4EBP1. The AMPK activator AICAR upregulated LC3‐II expression through the AMPK/mTOR pathway similar to the effects of MAC. MAC‐induced LC3‐II protein expression was slightly reduced in AMPK siRNA transfected cells. MAC upregulated hypoxia‐inducible factor‐1α (HIF‐1α) and BNIP3, which are HIF‐1α‐dependent autophagic proteins. Treatment with CoCl2, which mimics hypoxia, induced autophagy similar to the effect of MAC. The HIF‐1α inhibitor YC‐1 and HIF‐1α siRNA inhibited the MAC‐induced upregulation of LC3‐II and BNIP3. These results suggest that MAC induces autophagy via the AMPK/mTOR signalling pathway and by upregulating HIF‐1α and BNIP3 protein expression in lung cancer cells. [ABSTRACT FROM AUTHOR]

Substantial data from preclinical studies have revealed the biphasic effects of statins on cardiovascular angiogenesis. Although some have reported the anti-angiogenic potential of statins in malignant tumors, the underlying mechanism remains poorly understood. The aim of this study is to elucidate the mechanism by which simvastatin, a member of the statin family, inhibits tumor angiogenesis. Simvastatin significantly suppressed tumor cell-conditioned medium-induced angiogenic promotion in vitro, and resulted in dose-dependent anti-angiogenesis in vivo. Further genetic silencing of hypoxia-inducible factor-1α (HIF-1α) reduced vascular endothelial growth factor and fibroblast growth factor-2 expressions in 4T1 cells and correspondingly ameliorated HUVEC proliferation facilitated by tumor cell-conditioned medium. Additionally, simvastatin induced angiogenic inhibition through a mechanism of post-transcriptional downregulation of HIF-1α by increasing the phosphorylation level of AMP kinase. These results were further validated by the fact that 5- aminoimidazole-4-carboxamide ribonucleotide reduced HIF-1α protein levels and ameliorated the angiogenic ability of endothelial cells in vitro and in vivo. Critically, inhibition of AMPK phosphorylation by compound C almost completely abrogated simvastatin-induced anti-angiogenesis, which was accompanied by the reduction of protein levels of HIF-1α and its downstream pro-angiogenic factors. These findings reveal the mechanism by which simvastatin induces tumor anti-angiogenesis, and therefore identifies the target that explains the beneficial effects of statins on malignant tumors. [ABSTRACT FROM AUTHOR]