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Hagemann A, Altrogge PK, Kehrenberg MCA, Diehl D, Jung D, Weber L, Bachmann HS. Analyzing the postulated inhibitory effect of Manumycin A on farnesyltransferase. Front Chem 2022; 10:967947. [PMID: 36561140 PMCID: PMC9763582 DOI: 10.3389/fchem.2022.967947] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Accepted: 11/24/2022] [Indexed: 12/12/2022] Open
Abstract
Manumycin A is postulated to be a specific inhibitor against the farnesyltransferase (FTase) since this effect has been shown in 1993 for yeast FTase. Since then, plenty of studies investigated Manumycin A in human cells as well as in model organisms like Caenorhabditis elegans. Some studies pointed to additional targets and pathways involved in Manumycin A effects like apoptosis. Therefore, these studies created doubt whether the main mechanism of action of Manumycin A is FTase inhibition. For some of these alternative targets half maximal inhibitory concentrations (IC50) of Manumycin A are available, but not for human and C. elegans FTase. So, we aimed to 1) characterize missing C. elegans FTase kinetics, 2) elucidate the IC50 and Ki values of Manumycin A on purified human and C. elegans FTase 3) investigate Manumycin A dependent expression of FTase and apoptosis genes in C. elegans. C. elegans FTase has its temperature optimum at 40°C with KM of 1.3 µM (farnesylpyrophosphate) and 1.7 µM (protein derivate). Whilst other targets are inhibitable by Manumycin A at the nanomolar level, we found that Manumycin A inhibits cell-free FTase in micromolar concentrations (Ki human 4.15 μM; Ki C. elegans 3.16 μM). Furthermore, our gene expression results correlate with other studies indicating that thioredoxin reductase 1 is the main target of Manumycin A. According to our results, the ability of Manumycin A to inhibit the FTase at the micromolar level is rather neglectable for its cellular effects, so we postulate that the classification as a specific FTase inhibitor is no longer valid.
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Gendaszewska-Darmach E, Garstka MA, Błażewska KM. Targeting Small GTPases and Their Prenylation in Diabetes Mellitus. J Med Chem 2021; 64:9677-9710. [PMID: 34236862 PMCID: PMC8389838 DOI: 10.1021/acs.jmedchem.1c00410] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
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A fundamental role
of pancreatic β-cells to maintain proper
blood glucose level is controlled by the Ras superfamily of small
GTPases that undergo post-translational modifications, including prenylation.
This covalent attachment with either a farnesyl or a geranylgeranyl
group controls their localization, activity, and protein–protein
interactions. Small GTPases are critical in maintaining glucose homeostasis
acting in the pancreas and metabolically active tissues such as skeletal
muscles, liver, or adipocytes. Hyperglycemia-induced upregulation
of small GTPases suggests that inhibition of these pathways deserves
to be considered as a potential therapeutic approach in treating T2D.
This Perspective presents how inhibition of various points in the
mevalonate pathway might affect protein prenylation and functioning
of diabetes-affected tissues and contribute to chronic inflammation
involved in diabetes mellitus (T2D) development. We also demonstrate
the currently available molecular tools to decipher the mechanisms
linking the mevalonate pathway’s enzymes and GTPases with diabetes.
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Affiliation(s)
- Edyta Gendaszewska-Darmach
- Institute of Molecular and Industrial Biotechnology, Faculty of Biotechnology and Food Sciences, Lodz University of Technology, Stefanowskiego Street 4/10, 90-924 Łódź, Poland
| | - Malgorzata A Garstka
- Core Research Laboratory, Department of Endocrinology, Department of Tumor and Immunology, Precision Medical Institute, Western China Science and Technology Innovation Port, School of Medicine, the Second Affiliated Hospital of Xi'an Jiaotong University, DaMingGong, Jian Qiang Road, Wei Yang district, Xi'an 710016, China
| | - Katarzyna M Błażewska
- Institute of Organic Chemistry, Faculty of Chemistry, Lodz University of Technology, Żeromskiego Street 116, 90-924 Łódź, Poland
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Sakai K, Nagashima S, Wakabayashi T, Tumenbayar B, Hayakawa H, Hayakawa M, Karasawa T, Ohashi K, Yamazaki H, Takei A, Takei S, Yamamuro D, Takahashi M, Yagyu H, Osuga JI, Takahashi M, Tominaga SI, Ishibashi S. Myeloid HMG-CoA (3-Hydroxy-3-Methylglutaryl-Coenzyme A) Reductase Determines Atherosclerosis by Modulating Migration of Macrophages. Arterioscler Thromb Vasc Biol 2019; 38:2590-2600. [PMID: 30354246 DOI: 10.1161/atvbaha.118.311664] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Objective- Inhibition of HMGCR (3-hydroxy-3-methylglutaryl-coenzyme A reductase) is atheroprotective primarily by decreasing plasma LDL (low-density lipoprotein)-cholesterol. However, it is unknown whether inhibition of HMGCR in myeloid cells contributes to this atheroprotection. We sought to determine the role of myeloid HMGCR in the development of atherosclerosis. Approach and Results- We generated mice with genetically reduced Hmgcr in myeloid cells ( Hmgcr m- /m-) using LysM (Cre) and compared various functions of their macrophages to those of Hmgcr fl/fl control mice. We further compared the extent of atherosclerosis in Hmgcr m-/ m- and Hmgcr fl/fl mice in the absence of Ldlr (LDL receptor). Hmgcr m-/ m- macrophages and granulocytes had significantly lower Hmgcr mRNA expression and cholesterol biosynthesis than Hmgcr fl/fl cells. In vitro, Hmgcr m-/ m- monocytes/macrophages had reduced ability to migrate, proliferate, and survive compared with Hmgcr fl/fl monocytes/macrophages. However, there was no difference in ability to adhere, phagocytose, store lipids, or polarize to M1 macrophages between the 2 types of macrophages. The amounts of plasma membrane-associated small GTPase proteins, such as RhoA (RAS homolog family member A), were increased in Hmgcr m-/ m- macrophages. In the setting of Ldlr deficiency, Hmgcr m-/ m- mice developed significantly smaller atherosclerotic lesions than Hmgcr fl/fl mice. However, there were no differences between the 2 types of mice either in plasma lipoprotein profiles or in the numbers of proliferating or apoptotic cells in the lesions in vivo. The in vivo migration of Hmgcr m-/ m- macrophages to the lesions was reduced compared with Hmgcr fl/fl macrophages. Conclusions- Genetic reduction of HMGCR in myeloid cells may exert atheroprotective effects primarily by decreasing the migratory activity of monocytes/macrophages to the lesions.
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Affiliation(s)
- Kent Sakai
- From the Division of Endocrinology and Metabolism, Department of Medicine (K.S., S.N., T.W., B.T., H. Yamazaki, A.T., S.T., D.Y., M.T., H. Yagyu, J.-i.O., S.I.), Jichi Medical University, Shimotsuke, Tochigi, Japan
| | - Shuichi Nagashima
- From the Division of Endocrinology and Metabolism, Department of Medicine (K.S., S.N., T.W., B.T., H. Yamazaki, A.T., S.T., D.Y., M.T., H. Yagyu, J.-i.O., S.I.), Jichi Medical University, Shimotsuke, Tochigi, Japan
| | - Tetsuji Wakabayashi
- From the Division of Endocrinology and Metabolism, Department of Medicine (K.S., S.N., T.W., B.T., H. Yamazaki, A.T., S.T., D.Y., M.T., H. Yagyu, J.-i.O., S.I.), Jichi Medical University, Shimotsuke, Tochigi, Japan
| | - Bayasgalan Tumenbayar
- From the Division of Endocrinology and Metabolism, Department of Medicine (K.S., S.N., T.W., B.T., H. Yamazaki, A.T., S.T., D.Y., M.T., H. Yagyu, J.-i.O., S.I.), Jichi Medical University, Shimotsuke, Tochigi, Japan
| | - Hiroko Hayakawa
- Department of Biochemistry (H.H., M.H., S.-i.T.), Jichi Medical University, Shimotsuke, Tochigi, Japan
| | - Morisada Hayakawa
- Department of Biochemistry (H.H., M.H., S.-i.T.), Jichi Medical University, Shimotsuke, Tochigi, Japan
| | - Tadayoshi Karasawa
- Division of Inflammation Research, Center for Molecular Medicine (T.K., M.T.), Jichi Medical University, Shimotsuke, Tochigi, Japan
| | - Ken Ohashi
- Department of Metabolic Diseases, Graduate School of Medicine, The University of Tokyo, Bunkyo ward, Japan (K.O.)
| | - Hisataka Yamazaki
- From the Division of Endocrinology and Metabolism, Department of Medicine (K.S., S.N., T.W., B.T., H. Yamazaki, A.T., S.T., D.Y., M.T., H. Yagyu, J.-i.O., S.I.), Jichi Medical University, Shimotsuke, Tochigi, Japan
| | - Akihito Takei
- From the Division of Endocrinology and Metabolism, Department of Medicine (K.S., S.N., T.W., B.T., H. Yamazaki, A.T., S.T., D.Y., M.T., H. Yagyu, J.-i.O., S.I.), Jichi Medical University, Shimotsuke, Tochigi, Japan
| | - Shoko Takei
- From the Division of Endocrinology and Metabolism, Department of Medicine (K.S., S.N., T.W., B.T., H. Yamazaki, A.T., S.T., D.Y., M.T., H. Yagyu, J.-i.O., S.I.), Jichi Medical University, Shimotsuke, Tochigi, Japan
| | - Daisuke Yamamuro
- From the Division of Endocrinology and Metabolism, Department of Medicine (K.S., S.N., T.W., B.T., H. Yamazaki, A.T., S.T., D.Y., M.T., H. Yagyu, J.-i.O., S.I.), Jichi Medical University, Shimotsuke, Tochigi, Japan
| | - Manabu Takahashi
- From the Division of Endocrinology and Metabolism, Department of Medicine (K.S., S.N., T.W., B.T., H. Yamazaki, A.T., S.T., D.Y., M.T., H. Yagyu, J.-i.O., S.I.), Jichi Medical University, Shimotsuke, Tochigi, Japan
| | - Hiroaki Yagyu
- From the Division of Endocrinology and Metabolism, Department of Medicine (K.S., S.N., T.W., B.T., H. Yamazaki, A.T., S.T., D.Y., M.T., H. Yagyu, J.-i.O., S.I.), Jichi Medical University, Shimotsuke, Tochigi, Japan
| | - Jun-Ichi Osuga
- From the Division of Endocrinology and Metabolism, Department of Medicine (K.S., S.N., T.W., B.T., H. Yamazaki, A.T., S.T., D.Y., M.T., H. Yagyu, J.-i.O., S.I.), Jichi Medical University, Shimotsuke, Tochigi, Japan
| | - Masafumi Takahashi
- Division of Inflammation Research, Center for Molecular Medicine (T.K., M.T.), Jichi Medical University, Shimotsuke, Tochigi, Japan
| | - Shin-Ichi Tominaga
- Department of Biochemistry (H.H., M.H., S.-i.T.), Jichi Medical University, Shimotsuke, Tochigi, Japan
| | - Shun Ishibashi
- From the Division of Endocrinology and Metabolism, Department of Medicine (K.S., S.N., T.W., B.T., H. Yamazaki, A.T., S.T., D.Y., M.T., H. Yagyu, J.-i.O., S.I.), Jichi Medical University, Shimotsuke, Tochigi, Japan
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Updates on the Mechanisms and the Care of Cardiovascular Calcification in Chronic Kidney Disease. Semin Nephrol 2018; 38:233-250. [DOI: 10.1016/j.semnephrol.2018.02.004] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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Ponnusamy A, Sinha S, Hyde GD, Borland SJ, Taylor RF, Pond E, Eyre HJ, Inkson CA, Gilmore A, Ashton N, Kalra PA, Canfield AE. FTI-277 inhibits smooth muscle cell calcification by up-regulating PI3K/Akt signaling and inhibiting apoptosis. PLoS One 2018; 13:e0196232. [PMID: 29689070 PMCID: PMC5916518 DOI: 10.1371/journal.pone.0196232] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Accepted: 04/09/2018] [Indexed: 12/19/2022] Open
Abstract
Background Vascular calcification is associated with increased cardiovascular morbidity and mortality in patients with atherosclerosis, diabetes and chronic kidney disease. However, no viable treatments for this condition have been identified. This study aimed to determine whether farnesyl transferase inhibitors (FTIs) can reduce vascular calcification and the mechanism by which this reduction occurs. Results We demonstrate that FTI-277 significantly inhibits phosphate-induced mineral deposition by vascular smooth muscle cells (VSMC) in vitro, prevents VSMC osteogenic differentiation, and increases mRNA expression of matrix Gla protein (MGP), an inhibitor of mineralization. FTI-277 increases Akt signaling in VSMC in short-term serum-stimulation assays and in long-term mineralization assays. In contrast, manumycin A has no effect on Akt signaling or mineralization. Co-incubation of VSMC with FTI-277 and SH6 (an Akt inhibitor) significantly reduces the inhibitory effect of FTI-277 on mineralization, demonstrating that FTI-277 inhibits calcification by activating Akt signaling. Over-expression of the constitutively active p110 sub-unit of PI3K in VSMC using adenovirus activates Akt, inhibits mineralization, suppresses VSMC differentiation and significantly enhances MGP mRNA expression. FTI-277 also inhibits phosphate-induced activation of caspase 3 and apoptosis of VSMC, and these effects are negated by co-incubation with SH6. Finally, using an ex vivo model of vascular calcification, we demonstrate that FTI-277 inhibits high phosphate-induced mineralization in aortic rings derived from rats with end-stage renal failure. Conclusions Together, these results demonstrate that FTI-277 inhibits VSMC mineral deposition by up-regulating PI3K/Akt signaling and preventing apoptosis, suggesting that targeting farnesylation, or Akt specifically, may have therapeutic potential for the prevention of vascular calcification.
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MESH Headings
- Animals
- Apoptosis/drug effects
- Cattle
- Cell Differentiation/drug effects
- Cells, Cultured
- Disease Models, Animal
- Humans
- Male
- Methionine/analogs & derivatives
- Methionine/pharmacology
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/metabolism
- Myocytes, Smooth Muscle/cytology
- Myocytes, Smooth Muscle/drug effects
- Myocytes, Smooth Muscle/metabolism
- Osteogenesis/drug effects
- Phosphatidylinositol 3-Kinases/metabolism
- Proto-Oncogene Proteins c-akt/metabolism
- Rats
- Renal Insufficiency, Chronic/complications
- Renal Insufficiency, Chronic/genetics
- Renal Insufficiency, Chronic/metabolism
- Signal Transduction/drug effects
- Vascular Calcification/drug therapy
- Vascular Calcification/genetics
- Vascular Calcification/metabolism
- alpha-Galactosidase
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Affiliation(s)
- Arvind Ponnusamy
- Vascular Research Group, Salford Royal NHS Foundation Trust, Salford, United Kingdom
- Division of Cardiovascular Sciences, School of Medical Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Sciences Centre, University of Manchester, Manchester, United Kingdom
| | - Smeeta Sinha
- Vascular Research Group, Salford Royal NHS Foundation Trust, Salford, United Kingdom
- Division of Cardiovascular Sciences, School of Medical Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Sciences Centre, University of Manchester, Manchester, United Kingdom
| | - Gareth D. Hyde
- Division of Cardiovascular Sciences, School of Medical Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Sciences Centre, University of Manchester, Manchester, United Kingdom
| | - Samantha J. Borland
- Division of Cardiovascular Sciences, School of Medical Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Sciences Centre, University of Manchester, Manchester, United Kingdom
| | - Rebecca F. Taylor
- Division of Cardiovascular Sciences, School of Medical Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Sciences Centre, University of Manchester, Manchester, United Kingdom
| | - Emma Pond
- Division of Cardiovascular Sciences, School of Medical Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Sciences Centre, University of Manchester, Manchester, United Kingdom
| | - Heather J. Eyre
- Division of Cardiovascular Sciences, School of Medical Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Sciences Centre, University of Manchester, Manchester, United Kingdom
| | - Colette A. Inkson
- Division of Cardiovascular Sciences, School of Medical Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Sciences Centre, University of Manchester, Manchester, United Kingdom
| | - Andrew Gilmore
- Division of Cancer Studies & Wellcome Trust Centre for Cell-Matrix Research, School of Medical Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Sciences Centre, University of Manchester, Manchester, United Kingdom
| | - Nick Ashton
- Division of Cardiovascular Sciences, School of Medical Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Sciences Centre, University of Manchester, Manchester, United Kingdom
| | - Philip A. Kalra
- Vascular Research Group, Salford Royal NHS Foundation Trust, Salford, United Kingdom
- Division of Cardiovascular Sciences, School of Medical Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Sciences Centre, University of Manchester, Manchester, United Kingdom
| | - Ann E. Canfield
- Division of Cardiovascular Sciences, School of Medical Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Sciences Centre, University of Manchester, Manchester, United Kingdom
- * E-mail:
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Wang J, Yao X, Huang J. New tricks for human farnesyltransferase inhibitor: cancer and beyond. MEDCHEMCOMM 2017; 8:841-854. [PMID: 30108801 PMCID: PMC6072492 DOI: 10.1039/c7md00030h] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2017] [Accepted: 02/15/2017] [Indexed: 12/18/2022]
Abstract
Human protein farnesyltransferase (FTase) catalyzes the addition of a C15-farnesyl lipid group to the cysteine residue located in the COOH-terminal tetrapeptide motif of a variety of important substrate proteins, including well-known Ras protein superfamily. The farnesylation of Ras protein is required both for its normal physiological function, and for the transforming capacity of its oncogenic mutants. Over the last several decades, FTase inhibitors (FTIs) were developed to disrupt the farnesylation of oncogenic Ras as anti-cancer agents, and some of them have entered cancer clinical investigation. On the other hand, some substrates of FTase were demonstrated to be related with other human diseases, including Hutchinson-Gilford progeria syndrome, chronic hepatitis D, and cardiovascular diseases. In this review, we summarize the roles of FTase in malignant transformation, proliferation, apoptosis, angiogenesis, and metastasis of tumor cells, and the recently anticancer clinical research advances of FTIs. The therapeutic prospect of FTIs on several other human diseases is also discussed.
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Affiliation(s)
- Jingyuan Wang
- Shanghai Key Laboratory of New Drug Design , School of Pharmacy , East China University of Science and Technology , 130 Mei Long Road , Shanghai 200237 , China . ; Tel: (+86)21 64253681
| | - Xue Yao
- Shanghai Key Laboratory of New Drug Design , School of Pharmacy , East China University of Science and Technology , 130 Mei Long Road , Shanghai 200237 , China . ; Tel: (+86)21 64253681
| | - Jin Huang
- Shanghai Key Laboratory of New Drug Design , School of Pharmacy , East China University of Science and Technology , 130 Mei Long Road , Shanghai 200237 , China . ; Tel: (+86)21 64253681
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Zhao CZ, Zhao XM, Yang J, Mou Y, Chen B, Wu HD, Dai DP, Ding J, Hu SJ. Inhibition of farnesyl pyrophosphate synthase improves pressure overload induced chronic cardiac remodeling. Sci Rep 2016; 6:39186. [PMID: 28008986 PMCID: PMC5180215 DOI: 10.1038/srep39186] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Accepted: 11/16/2016] [Indexed: 12/19/2022] Open
Abstract
Farnesyl pyrophosphate synthase (FPPS) is a key enzyme in the mevalonate pathway. In our previous studies, we find that inhibition of FPPS attenuates angiotensin II-induced cardiac hypertrophy and fibrosis by suppressing RhoA while FPPS and Ras are up-regulated in pressure overload rats. In this study, we evaluate the effects and mechanisms of FPPS inhibition in pressure overload mice. Male FPPS-small interfering RNA (SiRNA) transgenic (Tg) mice and non-transgenic littermate control (NLC) were randomly divided into suprarenal abdominal aortic constriction (AAC) group and sham operation group. 12 weeks following AAC, mice were sacrificed by cervical dislocation. Histological and echocardiographic assessments showed that inhibition of FPPS improved chronic cardiac remodeling which was induced by AAC. The reductions of Ras farnesylation and GTP-Ras, as well as their downstream extracellular signal-related kinases 1/2 (ERK1/2) expression were observed in the heart of Tg-AAC mice compared with NLC-AAC mice, along with the reduction of fetal gene expression. We provide here important experimental evidence that inhibition of FPPS improves AAC induced chronic cardiac remodeling and fibrosis by the reduction of farnesylated Ras and the downregulation of Ras-ERK1/2 pathway.
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Affiliation(s)
- Chen-Ze Zhao
- From the Institute of Cardiology, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, PR China
| | - Xu-Ming Zhao
- From the Institute of Cardiology, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, PR China
| | - Jian Yang
- From the Institute of Cardiology, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, PR China
| | - Yun Mou
- Department of Ultrasound, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, PR China
| | - Bin Chen
- Department of Cardiology, Hangzhou First Municipal Hospital and Affiliated Hangzhou Hospital of Nanjing Medical University, Hangzhou, China
| | - Huan-Dong Wu
- From the Institute of Cardiology, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, PR China
| | - Dong-Pu Dai
- From the Institute of Cardiology, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, PR China
| | - Jie Ding
- From the Institute of Cardiology, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, PR China
| | - Shen-Jiang Hu
- From the Institute of Cardiology, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, PR China
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Solár P, Sačková V, Hrčková G, Demečková V, Kassayová M, Bojková B, Mudroňová D, Gancarčíková S, Jendželovský R, Fedoročko P. Antitumor effect of the combination of manumycin A and Immodin is associated with antiplatelet activity and increased granulocyte tumor infiltration in a 4T1 breast tumor model. Oncol Rep 2016; 37:368-378. [PMID: 27878284 DOI: 10.3892/or.2016.5265] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Accepted: 06/25/2016] [Indexed: 11/06/2022] Open
Abstract
Manumycin A is a natural antibiotic isolated from Streptomyces parvulus with broad range of biological activities including antineoplastic activity in several in vitro and in vivo cancer models. Immodin [dialyzable leukocyte extract (DLE)] is a dialysate released from disintegrated blood leukocytes of healthy donors which exerts immunonormalizing effects on cell-mediated immune responses. The aim of the present study was to explore the antitumor potential of the combination of manumycin A and Immodin in an experimental breast cancer model. Experiments were carried using a 4T1 tumor-bearing BALB/c mouse model. Survival analysis, tumor growth, hematological and biochemical profiles, leukocyte differential, phagocytic activity of leukocytes and histology of the primary tumor were examined. The combination treatment suppressed the tumor growth and prolonged the survival of tumor-bearing mice, decreased the number of monocytes, plateletes and plateletcrit in peripheral blood of the tumor-bearing mice and increased the infiltration of neutrophils and eosinophils in the primary tumor. Moreover, individual therapies enhanced the phagocytic activity of monocytes and neutrophils. These findings demonstrate the antitumor effect of the combination of manumycin A and Immodin in 4T1 tumor-bearing mice associated with strong antiplatelet activity and innate immunity activation.
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Affiliation(s)
- Peter Solár
- Institute of Biology and Ecology, Faculty of Science, Pavol Jozef Šafárik University in Košice, 041 54 Košice, Slovak Republic
| | - Veronika Sačková
- Institute of Biology and Ecology, Faculty of Science, Pavol Jozef Šafárik University in Košice, 041 54 Košice, Slovak Republic
| | - Gabriela Hrčková
- Institute of Parasitology of Slovak Academy of Science, 040 01 Košice, Slovak Republic
| | - Vlasta Demečková
- Institute of Biology and Ecology, Faculty of Science, Pavol Jozef Šafárik University in Košice, 041 54 Košice, Slovak Republic
| | - Monika Kassayová
- Institute of Biology and Ecology, Faculty of Science, Pavol Jozef Šafárik University in Košice, 041 54 Košice, Slovak Republic
| | - Bianka Bojková
- Institute of Biology and Ecology, Faculty of Science, Pavol Jozef Šafárik University in Košice, 041 54 Košice, Slovak Republic
| | - Dagmar Mudroňová
- University of Veterinary Medicine and Pharmacy, 041 81 Košice, Slovak Republic
| | - Soňa Gancarčíková
- University of Veterinary Medicine and Pharmacy, 041 81 Košice, Slovak Republic
| | - Rastislav Jendželovský
- Institute of Biology and Ecology, Faculty of Science, Pavol Jozef Šafárik University in Košice, 041 54 Košice, Slovak Republic
| | - Peter Fedoročko
- Institute of Biology and Ecology, Faculty of Science, Pavol Jozef Šafárik University in Košice, 041 54 Košice, Slovak Republic
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9
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Cecrdlova E, Petrickova K, Kolesar L, Petricek M, Sekerkova A, Svachova V, Striz I. Manumycin A downregulates release of proinflammatory cytokines from TNF alpha stimulated human monocytes. Immunol Lett 2015; 169:8-14. [PMID: 26602157 DOI: 10.1016/j.imlet.2015.11.010] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2015] [Revised: 09/24/2015] [Accepted: 11/13/2015] [Indexed: 01/02/2023]
Abstract
Macrolide antibiotics such as azithromycin or clarithromycin are known to have potent anti-inflammatory and immunomodulatory effects but these properties cannot be widely used due to a risk of bacterial resistance. We studied another polyketide antibiotic, structurally related manumycin A known as a streptomycete derived farnesyltransferase inhibitor with limited antibacterial effects, with respect to its potential regulation of mRNA expression of several genes associated with proinflammatory responses. Downregulation of mRNA for IL-6, TLR-8, IL-1 beta and IL-10 was found in THP-1 cells after 4h stimulation with TNF alpha in the presence of manumycin A and downregulated TLR-8 and EGR-1 genes were observed after 8h. Among the genes upregulated in response to manumycin were HMOX-1, TNFRSF10A, IL-1R1, TICAM2, NLRP12 after 4h and only IL-1R1 after 8h. Furthermore, manumycin A was found to inhibit IL-1beta, IL-6, and IL-8 production in TNF alpha stimulated THP-1 cells and peripheral blood monocytes in a dose dependent manner (0.25-1 μM of manumycin A) without affecting cell viability. Cell viability of blood monocytes decreased by about 30% at manumycin A doses of 2-5 μM. Manumycin A also inhibited IL-18 release from THP-1 cells, while in cultures of blood monocytes, this cytokine was not detectable. That manumycin A mediated downregulation of proinflammatory genes in human monocytes confirmed by a measurement of cytokine levels in culture supernatants, together with a very limited effect on cell viability, might suggest potential anti-inflammatory properties of this polyketide antibiotic.
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Affiliation(s)
- Eva Cecrdlova
- Department of Clinical and Transplant Immunology, Institute for Clinical and Experimental Medicine, Videnska 1958, 14021 Prague, Czech Republic
| | - Katerina Petrickova
- Institute of Microbiology, Academy of Sciences of the Czech Republic, Videnska 1083, 142 20 Prague, Czech Republic
| | - Libor Kolesar
- Department of Clinical and Transplant Immunology, Institute for Clinical and Experimental Medicine, Videnska 1958, 14021 Prague, Czech Republic
| | - Miroslav Petricek
- Institute of Microbiology, Academy of Sciences of the Czech Republic, Videnska 1083, 142 20 Prague, Czech Republic
| | - Alena Sekerkova
- Department of Clinical and Transplant Immunology, Institute for Clinical and Experimental Medicine, Videnska 1958, 14021 Prague, Czech Republic
| | - Veronika Svachova
- Department of Clinical and Transplant Immunology, Institute for Clinical and Experimental Medicine, Videnska 1958, 14021 Prague, Czech Republic
| | - Ilja Striz
- Department of Clinical and Transplant Immunology, Institute for Clinical and Experimental Medicine, Videnska 1958, 14021 Prague, Czech Republic.
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Lonafarnib is a potential inhibitor for neovascularization. PLoS One 2015; 10:e0122830. [PMID: 25853815 PMCID: PMC4390146 DOI: 10.1371/journal.pone.0122830] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2014] [Accepted: 02/15/2015] [Indexed: 11/19/2022] Open
Abstract
Atherosclerosis is a common cardiovascular disease that involves the build-up of plaque on the inner walls of the arteries. Intraplaque neovacularization has been shown to be essential in the pathogenesis of atherosclerosis. Previous studies showed that small-molecule compounds targeting farnesyl transferase have the ability to prevent atherosclerosis in apolipoprotein E-deficient mice, but the underlying mechanism remains to be elucidated. In this study, we found that lonafarnib, a specific inhibitor of farnesyl transferase, elicits inhibitory effect on vascular endothelial capillary assembly in vitro in a dose-dependent manner. In addition, we showed that lonafarnib treatment led to a dose-dependent decrease in scratch wound closure in vitro, whereas it had little effect on endothelial cell proliferation. These data indicate that lonafarnib inhibits neovascularization via directly targeting endothelial cells and disturbing their motility. Moreover, we demonstrated that pharmacological inhibition of farnesyl transferase by lonafarnib significantly impaired centrosome reorientation toward the leading edge of endothelial cells. Mechanistically, we found that the catalytic β subunit of farnesyl transferase associated with a cytoskeletal protein important for the establishment and maintenance of cell polarity. Additionally, we showed that lonafarnib remarkably inhibited the expression of the cytoskeletal protein and interrupted its interaction with farnesyl transferase. Our findings thus offer novel mechanistic insight into the protective effect of farnesyl transferase inhibitors on atherosclerosis and provide encouraging evidence for the potential use of this group of agents in inhibiting plaque neovascularization.
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11
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Nakazawa H, Yamada M, Tanaka T, Kramer J, Yu YM, Fischman AJ, Martyn JAJ, Tompkins RG, Kaneki M. Role of protein farnesylation in burn-induced metabolic derangements and insulin resistance in mouse skeletal muscle. PLoS One 2015; 10:e0116633. [PMID: 25594415 PMCID: PMC4296934 DOI: 10.1371/journal.pone.0116633] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2013] [Accepted: 12/11/2014] [Indexed: 01/04/2023] Open
Abstract
Objective Metabolic derangements, including insulin resistance and hyperlactatemia, are a major complication of major trauma (e.g., burn injury) and affect the prognosis of burn patients. Protein farnesylation, a posttranslational lipid modification of cysteine residues, has been emerging as a potential component of inflammatory response in sepsis. However, farnesylation has not yet been studied in major trauma. To study a role of farnesylation in burn-induced metabolic aberration, we examined the effects of farnesyltransferase (FTase) inhibitor, FTI-277, on burn-induced insulin resistance and metabolic alterations in mouse skeletal muscle. Methods A full thickness burn (30% total body surface area) was produced under anesthesia in male C57BL/6 mice at 8 weeks of age. After the mice were treated with FTI-277 (5 mg/kg/day, IP) or vehicle for 3 days, muscle insulin signaling, metabolic alterations and inflammatory gene expression were evaluated. Results Burn increased FTase expression and farnesylated proteins in mouse muscle compared with sham-burn at 3 days after burn. Simultaneously, insulin-stimulated phosphorylation of insulin receptor (IR), insulin receptor substrate (IRS)-1, Akt and GSK-3β was decreased. Protein expression of PTP-1B (a negative regulator of IR-IRS-1 signaling), PTEN (a negative regulator of Akt-mediated signaling), protein degradation and lactate release by muscle, and plasma lactate levels were increased by burn. Burn-induced impaired insulin signaling and metabolic dysfunction were associated with increased inflammatory gene expression. These burn-induced alterations were reversed or ameliorated by FTI-277. Conclusions Our data demonstrate that burn increased FTase expression and protein farnesylation along with insulin resistance, metabolic alterations and inflammatory response in mouse skeletal muscle, all of which were prevented by FTI-277 treatment. These results indicate that increased protein farnesylation plays a pivotal role in burn-induced metabolic dysfunction and inflammatory response. Our study identifies FTase as a novel potential molecular target to reverse or ameliorate metabolic derangements in burn patients.
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Affiliation(s)
- Harumasa Nakazawa
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts, United States of America
| | - Marina Yamada
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts, United States of America
- Shriners Hospitals for Children, Boston, Massachusetts, United States of America
| | - Tomokazu Tanaka
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts, United States of America
| | - Joshua Kramer
- Department of Pathology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Yong-Ming Yu
- Shriners Hospitals for Children, Boston, Massachusetts, United States of America
- Department of Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Alan J. Fischman
- Shriners Hospitals for Children, Boston, Massachusetts, United States of America
| | - J. A. Jeevendra Martyn
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts, United States of America
- Shriners Hospitals for Children, Boston, Massachusetts, United States of America
| | - Ronald G. Tompkins
- Shriners Hospitals for Children, Boston, Massachusetts, United States of America
- Department of Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Masao Kaneki
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts, United States of America
- Shriners Hospitals for Children, Boston, Massachusetts, United States of America
- * E-mail:
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12
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Yeganeh B, Wiechec E, Ande SR, Sharma P, Moghadam AR, Post M, Freed DH, Hashemi M, Shojaei S, Zeki AA, Ghavami S. Targeting the mevalonate cascade as a new therapeutic approach in heart disease, cancer and pulmonary disease. Pharmacol Ther 2014; 143:87-110. [PMID: 24582968 DOI: 10.1016/j.pharmthera.2014.02.007] [Citation(s) in RCA: 117] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2014] [Accepted: 02/04/2014] [Indexed: 12/21/2022]
Abstract
The cholesterol biosynthesis pathway, also known as the mevalonate (MVA) pathway, is an essential cellular pathway that is involved in diverse cell functions. The enzyme 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase (HMGCR) is the rate-limiting step in cholesterol biosynthesis and catalyzes the conversion of HMG-CoA to MVA. Given its role in cholesterol and isoprenoid biosynthesis, the regulation of HMGCR has been intensely investigated. Because all cells require a steady supply of MVA, both the sterol (i.e. cholesterol) and non-sterol (i.e. isoprenoid) products of MVA metabolism exert coordinated feedback regulation on HMGCR through different mechanisms. The proper functioning of HMGCR as the proximal enzyme in the MVA pathway is essential under both normal physiologic conditions and in many diseases given its role in cell cycle pathways and cell proliferation, cholesterol biosynthesis and metabolism, cell cytoskeletal dynamics and stability, cell membrane structure and fluidity, mitochondrial function, proliferation, and cell fate. The blockbuster statin drugs ('statins') directly bind to and inhibit HMGCR, and their use for the past thirty years has revolutionized the treatment of hypercholesterolemia and cardiovascular diseases, in particular coronary heart disease. Initially thought to exert their effects through cholesterol reduction, recent evidence indicates that statins also have pleiotropic immunomodulatory properties independent of cholesterol lowering. In this review we will focus on the therapeutic applications and mechanisms involved in the MVA cascade including Rho GTPase and Rho kinase (ROCK) signaling, statin inhibition of HMGCR, geranylgeranyltransferase (GGTase) inhibition, and farnesyltransferase (FTase) inhibition in cardiovascular disease, pulmonary diseases (e.g. asthma and chronic obstructive pulmonary disease (COPD)), and cancer.
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Affiliation(s)
- Behzad Yeganeh
- Hospital for Sick Children Research Institute, Department of Physiology & Experimental Medicine, University of Toronto, Toronto, Canada
| | - Emilia Wiechec
- Dept. Clinical & Experimental Medicine, Division of Cell Biology & Integrative Regenerative Med. Center (IGEN), Linköping University, Sweden
| | - Sudharsana R Ande
- Department of Internal Medicine, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Pawan Sharma
- Department of Physiology & Pharmacology, Snyder Institute for Chronic Diseases, Faculty of Medicine, University of Calgary, 4C46 HRIC, 3280 Hospital Drive NW, Calgary, Alberta, Canada
| | - Adel Rezaei Moghadam
- Scientific Association of Veterinary Medicine, Faculty of Veterinary Medicine, Tabriz Branch, Islamic Azad University, Tabriz, Iran; Young Researchers and Elite Club, Ardabil Branch, Islamic Azad University, Ardabil, Iran
| | - Martin Post
- Hospital for Sick Children Research Institute, Department of Physiology & Experimental Medicine, University of Toronto, Toronto, Canada
| | - Darren H Freed
- Department of Physiology, St. Boniface Research Centre, University of Manitoba, Winnipeg, Canada
| | - Mohammad Hashemi
- Cellular and Molecular Research Center, Zahedan University of Medical Sciences, Zahedan, Iran
| | - Shahla Shojaei
- Department of Biochemistry, Recombinant Protein Laboratory, Medical School, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Amir A Zeki
- U.C. Davis, School of Medicine, U.C. Davis Medical Center, Department of Internal Medicine, Division of Pulmonary, Critical Care, and Sleep Medicine, Center for Comparative Respiratory Biology & Medicine, Davis, CA, USA.
| | - Saeid Ghavami
- Department of Human Anatomy and Cell Science, St. Boniface Research Centre, Manitoba Institute of Child Health, Biology of Breathing Theme, University of Manitoba, Winnipeg, Canada.
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Abstract
At least 468 individual genes have been manipulated by molecular methods to study their effects on the initiation, promotion, and progression of atherosclerosis. Most clinicians and many investigators, even in related disciplines, find many of these genes and the related pathways entirely foreign. Medical schools generally do not attempt to incorporate the relevant molecular biology into their curriculum. A number of key signaling pathways are highly relevant to atherogenesis and are presented to provide a context for the gene manipulations summarized herein. The pathways include the following: the insulin receptor (and other receptor tyrosine kinases); Ras and MAPK activation; TNF-α and related family members leading to activation of NF-κB; effects of reactive oxygen species (ROS) on signaling; endothelial adaptations to flow including G protein-coupled receptor (GPCR) and integrin-related signaling; activation of endothelial and other cells by modified lipoproteins; purinergic signaling; control of leukocyte adhesion to endothelium, migration, and further activation; foam cell formation; and macrophage and vascular smooth muscle cell signaling related to proliferation, efferocytosis, and apoptosis. This review is intended primarily as an introduction to these key signaling pathways. They have become the focus of modern atherosclerosis research and will undoubtedly provide a rich resource for future innovation toward intervention and prevention of the number one cause of death in the modern world.
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Affiliation(s)
- Paul N Hopkins
- Cardiovascular Genetics, Department of Internal Medicine, University of Utah, Salt Lake City, Utah, USA.
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14
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Loirand G, Sauzeau V, Pacaud P. Small G Proteins in the Cardiovascular System: Physiological and Pathological Aspects. Physiol Rev 2013; 93:1659-720. [DOI: 10.1152/physrev.00021.2012] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Small G proteins exist in eukaryotes from yeast to human and constitute the Ras superfamily comprising more than 100 members. This superfamily is structurally classified into five families: the Ras, Rho, Rab, Arf, and Ran families that control a wide variety of cell and biological functions through highly coordinated regulation processes. Increasing evidence has accumulated to identify small G proteins and their regulators as key players of the cardiovascular physiology that control a large panel of cardiac (heart rhythm, contraction, hypertrophy) and vascular functions (angiogenesis, vascular permeability, vasoconstriction). Indeed, basal Ras protein activity is required for homeostatic functions in physiological conditions, but sustained overactivation of Ras proteins or spatiotemporal dysregulation of Ras signaling pathways has pathological consequences in the cardiovascular system. The primary object of this review is to provide a comprehensive overview of the current progress in our understanding of the role of small G proteins and their regulators in cardiovascular physiology and pathologies.
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Affiliation(s)
- Gervaise Loirand
- INSERM, UMR S1087; University of Nantes; and CHU Nantes, l'Institut du Thorax, Nantes, France
| | - Vincent Sauzeau
- INSERM, UMR S1087; University of Nantes; and CHU Nantes, l'Institut du Thorax, Nantes, France
| | - Pierre Pacaud
- INSERM, UMR S1087; University of Nantes; and CHU Nantes, l'Institut du Thorax, Nantes, France
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15
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Nikolov IG, Joki N, Galmiche A, Nguyen-Khoa T, Guerrera IC, Guillonneau F, Ivanovski O, Phan O, Maizel J, Marçon F, Benchitrit J, Lucas A, Edelman A, Lacour B, Drüeke TB, Massy ZA. Farnesyltransferase inhibitor R115777 protects against vascular disease in uremic mice. Atherosclerosis 2013; 229:42-51. [DOI: 10.1016/j.atherosclerosis.2013.02.041] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/02/2012] [Revised: 02/08/2013] [Accepted: 02/25/2013] [Indexed: 11/26/2022]
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16
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Rui Z, Sandy M, Jung B, Zhang W. Tandem Enzymatic Oxygenations in Biosynthesis of Epoxyquinone Pharmacophore of Manumycin-type Metabolites. ACTA ACUST UNITED AC 2013; 20:879-87. [DOI: 10.1016/j.chembiol.2013.05.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2013] [Revised: 04/23/2013] [Accepted: 05/09/2013] [Indexed: 11/25/2022]
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17
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Mulay V, Wood P, Manetsch M, Darabi M, Cairns R, Hoque M, Chan KC, Reverter M, Alvarez-Guaita A, Rye KA, Rentero C, Heeren J, Enrich C, Grewal T. Inhibition of mitogen-activated protein kinase Erk1/2 promotes protein degradation of ATP binding cassette transporters A1 and G1 in CHO and HuH7 cells. PLoS One 2013; 8:e62667. [PMID: 23634230 PMCID: PMC3636258 DOI: 10.1371/journal.pone.0062667] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2012] [Accepted: 03/22/2013] [Indexed: 12/13/2022] Open
Abstract
Signal transduction modulates expression and activity of cholesterol transporters. We recently demonstrated that the Ras/mitogen-activated protein kinase (MAPK) signaling cascade regulates protein stability of Scavenger Receptor BI (SR-BI) through Proliferator Activator Receptor (PPARα) -dependent degradation pathways. In addition, MAPK (Mek/Erk 1/2) inhibition has been shown to influence liver X receptor (LXR) -inducible ATP Binding Cassette (ABC) transporter ABCA1 expression in macrophages. Here we investigated if Ras/MAPK signaling could alter expression and activity of ABCA1 and ABCG1 in steroidogenic and hepatic cell lines. We demonstrate that in Chinese Hamster Ovary (CHO) cells and human hepatic HuH7 cells, extracellular signal-regulated kinase 1/2 (Erk1/2) inhibition reduces PPARα-inducible ABCA1 protein levels, while ectopic expression of constitutively active H-Ras, K-Ras and MAPK/Erk kinase 1 (Mek1) increases ABCA1 protein expression, respectively. Furthermore, Mek1/2 inhibitors reduce ABCG1 protein levels in ABCG1 overexpressing CHO cells (CHO-ABCG1) and human embryonic kidney 293 (HEK293) cells treated with LXR agonist. This correlates with Mek1/2 inhibition reducing ABCG1 cell surface expression and decreasing cholesterol efflux onto High Density Lipoproteins (HDL). Real Time reverse transcriptase polymerase chain reaction (RT-PCR) and protein turnover studies reveal that Mek1/2 inhibitors do not target transcriptional regulation of ABCA1 and ABCG1, but promote ABCA1 and ABCG1 protein degradation in HuH7 and CHO cells, respectively. In line with published data from mouse macrophages, blocking Mek1/2 activity upregulates ABCA1 and ABCG1 protein levels in human THP1 macrophages, indicating opposite roles for the Ras/MAPK pathway in the regulation of ABC transporter activity in macrophages compared to steroidogenic and hepatic cell types. In summary, this study suggests that Ras/MAPK signaling modulates PPARα- and LXR-dependent protein degradation pathways in a cell-specific manner to regulate the expression levels of ABCA1 and ABCG1 transporters.
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Affiliation(s)
- Vishwaroop Mulay
- Faculty of Pharmacy, University of Sydney, Sydney, New South Wales, Australia
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18
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Miles RR, Perry W, Haas JV, Mosior MK, N'Cho M, Wang JWJ, Yu P, Calley J, Yue Y, Carter Q, Han B, Foxworthy P, Kowala MC, Ryan TP, Solenberg PJ, Michael LF. Genome-wide screen for modulation of hepatic apolipoprotein A-I (ApoA-I) secretion. J Biol Chem 2013; 288:6386-96. [PMID: 23322769 DOI: 10.1074/jbc.m112.410092] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Control of plasma cholesterol levels is a major therapeutic strategy for management of coronary artery disease (CAD). Although reducing LDL cholesterol (LDL-c) levels decreases morbidity and mortality, this therapeutic intervention only translates into a 25-40% reduction in cardiovascular events. Epidemiological studies have shown that a high LDL-c level is not the only risk factor for CAD; low HDL cholesterol (HDL-c) is an independent risk factor for CAD. Apolipoprotein A-I (ApoA-I) is the major protein component of HDL-c that mediates reverse cholesterol transport from tissues to the liver for excretion. Therefore, increasing ApoA-I levels is an attractive strategy for HDL-c elevation. Using genome-wide siRNA screening, targets that regulate hepatocyte ApoA-I secretion were identified through transfection of 21,789 siRNAs into hepatocytes whereby cell supernatants were assayed for ApoA-I. Approximately 800 genes were identified and triaged using a convergence of information, including genetic associations with HDL-c levels, tissue-specific gene expression, druggability assessments, and pathway analysis. Fifty-nine genes were selected for reconfirmation; 40 genes were confirmed. Here we describe the siRNA screening strategy, assay implementation and validation, data triaging, and example genes of interest. The genes of interest include known and novel genes encoding secreted enzymes, proteases, G-protein-coupled receptors, metabolic enzymes, ion transporters, and proteins of unknown function. Repression of farnesyltransferase (FNTA) by siRNA and the enzyme inhibitor manumycin A caused elevation of ApoA-I secretion from hepatocytes and from transgenic mice expressing hApoA-I and cholesterol ester transfer protein transgenes. In total, this work underscores the power of functional genetic assessment to identify new therapeutic targets.
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Affiliation(s)
- Rebecca R Miles
- Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, Indiana 46285, USA
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19
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Chan SHH, Chan JYH, Hsu KS, Li FCH, Sun EYH, Chen WL, Chang AYW. Amelioration of central cardiovascular regulatory dysfunction by tropomyocin receptor kinase B in a mevinphos intoxication model of brain stem death. Br J Pharmacol 2012; 164:2015-28. [PMID: 21615729 DOI: 10.1111/j.1476-5381.2011.01508.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
BACKGROUND AND PURPOSE Little information exists on the mechanisms that precipitate brain stem death, the legal definition of death in many developed countries. We investigated the role of tropomyocin receptor kinase B (TrkB) and its downstream signalling pathways in the rostral ventrolateral medulla (RVLM) during experimental brain stem death. EXPERIMENTAL APPROACH An experimental model of brain stem death that employed microinjection of the organophosphate insecticide mevinphos bilaterally into the RVLM of Sprague-Dawley rats was used, in conjunction with cardiovascular, pharmacological and biochemical evaluations. KEY RESULTS A significant increase in TrkB protein, phosphorylation of TrkB at Tyr(516) (pTrkB(Y516) ), Shc at Tyr(317) (pShc(Y317) ) or ERK at Thr(202) /Tyr(204) , or Ras activity in RVLM occurred preferentially during the pro-life phase of experimental brain stem death. Microinjection bilaterally into RVLM of a specific TrkB inhibitor, K252a, antagonized those increases. Pretreatment with anti-pShc(Y317) antiserum, Src homology 3 binding peptide (Grb2/SOS inhibitor), farnesylthioacetic acid (Ras inhibitor), manumycin A (Ras inhibitor) or GW5074 (Raf-1 inhibitor) blunted the preferential augmentation of Ras activity or ERK phosphorylation in RVLM and blocked the up-regulated NOS I/protein kinase G (PKG) signalling, the pro-life cascade that sustains central cardiovascular regulation during experimental brain stem death. CONCLUSIONS AND IMPLICATIONS Activation of TrkB, followed by recruitment of Shc/Grb2/SOS adaptor proteins, leading to activation of Ras/Raf-1/ERK signalling pathway plays a crucial role in ameliorating central cardiovascular regulatory dysfunction via up-regulation of NOS I/PKG signalling cascade in the RVLM in brain stem death. These findings provide novel information for developing therapeutic strategies against this fatal eventuality.
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Affiliation(s)
- S H H Chan
- Center for Translational Researchin Biomedical Sciences,Chang Gung Memorial Hospital-Kaohsiung Medical Center, Kaohsiung, Taiwan
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20
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Yang W, Yamada M, Tamura Y, Chang K, Mao J, Zou L, Feng Y, Kida K, Scherrer-Crosbie M, Chao W, Ichinose F, Yu YM, Fischman AJ, Tompkins RG, Yao S, Kaneki M. Farnesyltransferase inhibitor FTI-277 reduces mortality of septic mice along with improved bacterial clearance. J Pharmacol Exp Ther 2011; 339:832-41. [PMID: 21873557 DOI: 10.1124/jpet.111.183558] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Treatment with statins, inhibitors of HMG-CoA reductase, extends the survival of septic mice. However, the molecular mechanisms underlying the cholesterol-lowering, independent beneficial effects of statins in sepsis are poorly understood. The inhibition of protein isoprenylation, namely farnesylation and geranylgeranylation, has been proposed as a mediator of the pleiotropic protective effects of statins, although direct evidence is lacking. Major features of sepsis-induced immune suppression include T-cell dysfunction, which is characterized by apoptosis of splenic T cells, increased CD4(+)Foxp3(+) regulatory T cells (Tregs), and suppression of type 1 helper T-cell response [e.g., interferon-γ (IFN-γ) secretion] in mice. Here, we show that the induction of sepsis by cecal ligation and puncture (CLP) resulted in increases in farnesyltransferase activity and farnesylated proteins in the spleen relative to sham operation. Treatment with farnesyltransferase inhibitor N-[4-[2(R)-amino-3-mercaptopropyl]amino-2-phenylbenzoyl]methionine methyl ester trifluoroacetate salt (FTI-277) (25 mg/kg b.wt. i.p.) at 2 h after CLP blocked the increase in farnesylated proteins and improved survival and bacterial clearance of septic mice. FTI-277 reverted to or mitigated sepsis-induced apoptosis in spleen and thymus, increased splenic CD4(+)Foxp3(+) Tregs, and suppressed IFN-γ secretion and proliferation of splenocytes in response to anti-CD3+CD28 antibodies in mice. Moreover, FTI-277 promoted macrophage phagocytotic activity in septic mice. These results indicate that elevation in protein farnesylation plays a role in derangements in immune function and mortality of septic mice. These findings suggest that prevention of immune dysfunction might contribute to FTI-277-induced improvement in survival of septic mice. These data highlight protein farnesyltransferase as a novel potential molecular target to reduce the mortality of patients with sepsis.
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Affiliation(s)
- Wen Yang
- Department of Anesthesia, Critical Care, and Pain Medicine, Massachusetts General Hospital, Harvard Medical School,Charlestown, Massachusetts, USA
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Role of endothelial dysfunction in modulating the plasma redox homeostasis in visceral leishmaniasis. Biochim Biophys Acta Gen Subj 2011; 1810:652-65. [DOI: 10.1016/j.bbagen.2011.03.019] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2010] [Revised: 03/11/2011] [Accepted: 03/31/2011] [Indexed: 01/12/2023]
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22
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Wood P, Mulay V, Darabi M, Chan KC, Heeren J, Pol A, Lambert G, Rye KA, Enrich C, Grewal T. Ras/mitogen-activated protein kinase (MAPK) signaling modulates protein stability and cell surface expression of scavenger receptor SR-BI. J Biol Chem 2011; 286:23077-92. [PMID: 21525007 DOI: 10.1074/jbc.m111.236398] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The mitogen-activated protein kinase (MAPK) Erk1/2 has been implicated to modulate the activity of nuclear receptors, including peroxisome proliferator activator receptors (PPARs) and liver X receptor, to alter the ability of cells to export cholesterol. Here, we investigated if the Ras-Raf-Mek-Erk1/2 signaling cascade could affect reverse cholesterol transport via modulation of scavenger receptor class BI (SR-BI) levels. We demonstrate that in Chinese hamster ovary (CHO) and human embryonic kidney (HEK293) cells, Mek1/2 inhibition reduces PPARα-inducible SR-BI protein expression and activity, as judged by reduced efflux onto high density lipoprotein (HDL). Ectopic expression of constitutively active H-Ras and Mek1 increases SR-BI protein levels, which correlates with elevated PPARα Ser-21 phosphorylation and increased cholesterol efflux. In contrast, SR-BI levels are insensitive to Mek1/2 inhibitors in PPARα-depleted cells. Most strikingly, Mek1/2 inhibition promotes SR-BI degradation in SR-BI-overexpressing CHO cells and human HuH7 hepatocytes, which is associated with reduced uptake of radiolabeled and 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyane-labeled HDL. Loss of Mek1/2 kinase activity reduces SR-BI expression in the presence of bafilomycin, an inhibitor of lysosomal degradation, indicating down-regulation of SR-BI via proteasomal pathways. In conclusion, Mek1/2 inhibition enhances the PPARα-dependent degradation of SR-BI in hepatocytes.
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Affiliation(s)
- Peta Wood
- Faculty of Pharmacy, University of Sydney, Sydney, New South Wales 2006, Australia
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Sadowitz B, Maier KG, Gahtan V. Basic Science Review: Statin Therapy-Part I: The Pleiotropic Effects of Statins in Cardiovascular Disease. Vasc Endovascular Surg 2010; 44:241-51. [DOI: 10.1177/1538574410362922] [Citation(s) in RCA: 108] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
3-hydroxy-3-methylglutaryl coenzyme A reductase (HMG CoA-reductase) inhibitors, otherwise known as statins, are currently the medical treatment of choice for hypercholesterolemia. Hypercholesterolemia is a known risk factor for cardiovascular disease, and statin therapy has led to a significant reduction in morbidity and mortality from adverse cardiac events, stroke, and peripheral arterial disease. In addition to achieving a therapeutic decrease in serum cholesterol levels, statin therapy appears to promote other effects that are independent of changes in serum cholesterol. These ‘‘pleiotropic’’ effects include attenuation of vascular inflammation, improved endothelial cell function, stabilization of atherosclerotic plaque, decreased vascular smooth muscle cell migration and proliferation, and inhibition of platelet aggregation. This article is part I of a 2-part review, and it focuses on the pleiotropic effects of statins at the cellular level.
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Affiliation(s)
- Benjamin Sadowitz
- SUNY Upstate Medical University, Division of Vascular Surgery and Endovascular Services, Syracuse, NY, USA, Department of Veterans Affairs VA Healthcare Network Upstate New York at Syracuse, Syracuse, NY, USA
| | - Kristopher G. Maier
- SUNY Upstate Medical University, Division of Vascular Surgery and Endovascular Services, Syracuse, NY, USA, Department of Veterans Affairs VA Healthcare Network Upstate New York at Syracuse, Syracuse, NY, USA,
| | - Vivian Gahtan
- SUNY Upstate Medical University, Division of Vascular Surgery and Endovascular Services, Syracuse, NY, USA, Department of Veterans Affairs VA Healthcare Network Upstate New York at Syracuse, Syracuse, NY, USA
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Sangle GV, Shen GX. Signaling mechanisms for oxidized LDL-induced oxidative stress and the upregulation of plasminogen activator inhibitor-1 in vascular cells. ACTA ACUST UNITED AC 2010. [DOI: 10.2217/clp.10.6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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Shinozaki S, Inoue Y, Yang W, Fukaya M, Carter EA, Yu YM, Ming-Yu Y, Fischman A, Tompkins R, Kaneki M. Farnesyltransferase inhibitor improved survival following endotoxin challenge in mice. Biochem Biophys Res Commun 2009; 391:1459-64. [PMID: 20034462 DOI: 10.1016/j.bbrc.2009.12.094] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2009] [Accepted: 12/16/2009] [Indexed: 01/09/2023]
Abstract
Endotoxemia plays an important role in the pathogenesis of sepsis and is accompanied by dysregulated apoptosis of immune and non-immune cells. Treatment with statins reduces mortality in rodent models of sepsis and endotoxemia. Inhibition of protein isoprenylation, including farnesylation, has been proposed as a mechanism to mediate the lipid-lowering-independent effects of statins. Nonetheless, the effects of the inhibition of isoprenylation have not yet been studied. To investigate the role of farnesylation, we evaluated the effects of farnesyltransferase inhibitor and statin on survival following lipopolysaccharide (LPS) challenge in mice. Both simvastatin (2mg/kg BW) and FTI-277 (20mg/kg BW) treatment improved survival by twofold after LPS injection, as compared with vehicle alone (p<0.01). LPS-induced cleavage (activation) of caspase-3, an indicator of apoptotic change, and increased protein expression of proapoptotic molecules, Bax and Bim, and activation of c-Jun NH(2)-terminal kinase (JNK/SAPK) in the liver and spleen were attenuated by both simvastatin and FTI-277. These results demonstrate that farnesyltransferase inhibitor as well as statin significantly reduced LPS-induced mortality in mice. Our findings also suggest that inhibition of protein farnesylation may contribute to the lipid-lowering-independent protective effects of statins in endotoxemia, and that protein farnesylation may play a role in LPS-induced stress response, including JNK/SAPK activation, and apoptotic change. Our data argue that farnesyltransferase may be a potential molecular target for treating patients with endotoxemia.
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Saha B, Nandi D. Farnesyltransferase inhibitors reduce Ras activation and ameliorate acetaminophen-induced liver injury in mice. Hepatology 2009; 50:1547-57. [PMID: 19739265 DOI: 10.1002/hep.23180] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
UNLABELLED Hepatotoxicity due to overdose of the analgesic and antipyretic acetaminophen (APAP) is a major cause of liver failure in adults. To better understand the contributions of different signaling pathways, the expression and role of Ras activation was evaluated after oral dosing of mice with APAP (400-500 mg/kg). Ras-guanosine triphosphate (GTP) is induced early and in an oxidative stress-dependent manner. The functional role of Ras activation was studied by a single intraperitoneal injection of the neutral sphingomyelinase and farnesyltransferase inhibitor (FTI) manumycin A (1 mg/kg), which lowers induction of Ras-GTP and serum amounts of alanine aminotransferase (ALT). APAP dosing decreases hepatic glutathione amounts, which are not affected by manumycin A treatment. However, APAP-induced activation of c-Jun N-terminal kinase, which plays an important role, is reduced by manumycin A. Also, APAP-induced mitochondrial reactive oxygen species are reduced by manumycin A at a later time point during liver injury. Importantly, the induction of genes involved in the inflammatory response (including iNos, gp91phox, and Fasl) and serum amounts of proinflammatory cytokines interferon-gamma (IFNgamma) and tumor necrosis factor alpha, which increase greatly with APAP challenge, are suppressed with manumycin A. The FTI activity of manumycin A is most likely involved in reducing APAP-induced liver injury, because a specific neutral sphingomyelinase inhibitor, GW4869 (1 mg/kg), did not show any hepatoprotective effect. Notably, a structurally distinct FTI, gliotoxin (1 mg/kg), also inhibits Ras activation and reduces serum amounts of ALT and IFN-gamma after APAP dosing. Finally, histological analysis confirmed the hepatoprotective effect of manumycin A and gliotoxin during APAP-induced liver damage. CONCLUSION This study identifies a key role for Ras activation and demonstrates the therapeutic efficacy of FTIs during APAP-induced liver injury.
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Affiliation(s)
- Banishree Saha
- Department of Biochemistry, Indian Institute of Science, Bangalore, India
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Capell BC, Olive M, Erdos MR, Cao K, Faddah DA, Tavarez UL, Conneely KN, Qu X, San H, Ganesh SK, Chen X, Avallone H, Kolodgie FD, Virmani R, Nabel EG, Collins FS. A farnesyltransferase inhibitor prevents both the onset and late progression of cardiovascular disease in a progeria mouse model. Proc Natl Acad Sci U S A 2008; 105:15902-7. [PMID: 18838683 PMCID: PMC2562418 DOI: 10.1073/pnas.0807840105] [Citation(s) in RCA: 152] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2008] [Indexed: 01/15/2023] Open
Abstract
Hutchinson-Gilford progeria syndrome (HGPS) is the most dramatic form of human premature aging. Death occurs at a mean age of 13 years, usually from heart attack or stroke. Almost all cases of HGPS are caused by a de novo point mutation in the lamin A (LMNA) gene that results in production of a mutant lamin A protein termed progerin. This protein is permanently modified by a lipid farnesyl group, and acts as a dominant negative, disrupting nuclear structure. Treatment with farnesyltransferase inhibitors (FTIs) has been shown to prevent and even reverse this nuclear abnormality in cultured HGPS fibroblasts. We have previously created a mouse model of HGPS that shows progressive loss of vascular smooth muscle cells in the media of the large arteries, in a pattern that is strikingly similar to the cardiovascular disease seen in patients with HGPS. Here we show that the dose-dependent administration of the FTI tipifarnib (R115777, Zarnestra) to this HGPS mouse model can significantly prevent both the onset of the cardiovascular phenotype as well as the late progression of existing cardiovascular disease. These observations provide encouraging evidence for the current clinical trial of FTIs for this rare and devastating disease.
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Affiliation(s)
- Brian C. Capell
- *Genome Technology Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892-8004
- New York University School of Medicine, New York, NY 10016
| | - Michelle Olive
- *Genome Technology Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892-8004
| | - Michael R. Erdos
- *Genome Technology Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892-8004
| | - Kan Cao
- *Genome Technology Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892-8004
| | - Dina A. Faddah
- *Genome Technology Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892-8004
| | - Urraca L. Tavarez
- *Genome Technology Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892-8004
| | - Karen N. Conneely
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA 30322
| | - Xuan Qu
- *Genome Technology Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892-8004
| | - Hong San
- *Genome Technology Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892-8004
| | - Santhi K. Ganesh
- *Genome Technology Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892-8004
| | - Xiaoyan Chen
- *Genome Technology Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892-8004
| | | | | | | | - Elizabeth G. Nabel
- *Genome Technology Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892-8004
- National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892
| | - Francis S. Collins
- *Genome Technology Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892-8004
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Transactivation of epidermal growth factor receptor in vascular and renal systems in rats with experimental hyperleptinemia: role in leptin-induced hypertension. Biochem Pharmacol 2008; 75:1623-38. [PMID: 18282556 DOI: 10.1016/j.bcp.2008.01.003] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2007] [Revised: 12/28/2007] [Accepted: 01/02/2008] [Indexed: 01/09/2023]
Abstract
We examined the role of epidermal growth factor (EGF) receptor in the pathogenesis of leptin-induced hypertension in the rat. Leptin, administered in increasing doses (0.1-0.5 mg/kg/day) for 10 days, increased phosphorylation levels of non-receptor tyrosine kinase, c-Src, EGF receptor and extracellular signal-regulated kinases (ERK) in aorta and kidney, which was accompanied by the increase in plasma concentration and urinary excretion of isoprostanes and H2O2. Blood pressure and renal Na+,K+-ATPase activity were higher, whereas urinary sodium excretion was lower in animals receiving leptin. The effects of leptin on renal Na+,K+-ATPase, natriuresis and blood pressure were abolished by NADPH oxidase inhibitor, apocynin, Src kinase inhibitor, PP2, EGF receptor inhibitor, AG1478, protein farnesyltransferase inhibitor, manumycin A, and ERK inhibitor, PD98059. In contrast, inhibitors of insulin-like growth factor-1 and platelet-derived growth factor receptors, AG1024 and AG1295, respectively, only slightly reduced ERK phosphorylation and had no effect on blood pressure in rats receiving leptin. These data indicate that: (1) experimental hyperleptinemia is associated with oxidative stress and c-Src-dependent transactivation of the EGF receptor, which stimulates ERK in vascular wall and the kidney, (2) overactivity of EGF receptor-ERK pathway contributes to leptin-induced hypertension by stimulating renal Na+,K+-ATPase and reducing sodium excretion, (3) inhibitors of c-Src, EGF receptor and ERK may be considered as a novel therapy for hypertension associated with hyperleptinemia, e.g. in patients with obesity and metabolic syndrome.
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