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Watanabe Y, Yamagishi S, Takata N, Tsuyama T, Yasue K, Ohno Y. Formation of xylem tissues and secondary cell walls is diminished by severe and consecutive insect defoliation. Am J Bot 2023; 110:e16232. [PMID: 37661818 DOI: 10.1002/ajb2.16232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Revised: 08/03/2023] [Accepted: 08/04/2023] [Indexed: 09/05/2023]
Abstract
PREMISE Insect defoliation of trees causes unusual changes to wood anatomy and slows radial growth that decreases tree value; however, the characteristics of these anatomical changes in hardwoods remain unclear. The aim of this study was to characterize the anatomy and histochemistry of the wood in trunks of Betula maximowicziana trees after severe insect defoliation. METHODS Secondary xylem tissues were sampled from trunks that had been defoliated by Caligula japonica at Naie and Furano in central Hokkaido during 2006-2012, then cross-dated and examined microscopically and stained histochemically to characterize anatomical and chemical changes in the cells. RESULTS White rings with thin-walled wood fibers and greatly reduced annual ring width in the subsequent year were observed in samples from both sites. From these results, the year that the white rings formed was determined, and severe defoliation was confirmed to trigger white ring formation. The characteristics may prove useful to detect the formation year of white rings. Scanning electron microscopy and histochemical analyses of the white rings indicated that the thickness of the S2 layer in the wall of wood fiber cells decreased, but xylan and lignin were still deposited in the cell walls of wood fibers. However, the walls of the fibers rethickened after the defoliation. CONCLUSIONS Our results suggest that B. maximowicziana responds to a temporary lack of carbon inputs due to insect defoliation by regulating the thickness of the S2 layer of the cell wall of wood fibers. For B. maximowicziana, insect defoliation late in the growing season has serious deleterious effects on wood formation and radial growth.
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Affiliation(s)
- Yoko Watanabe
- Research Faculty of Agriculture, Hokkaido University, Sapporo, 060-8589, Japan
| | - Shohei Yamagishi
- Graduate School of Agriculture, Hokkaido University, Sapporo, 060-8589, Japan
- Forestry and Forest Products Research Institute, Tsukuba, 305-8687, Japan
| | - Naoki Takata
- Forest Bio-Research Center, Forestry and Forest Products Research Institute, Hitachi, 319-1301, Japan
| | - Taku Tsuyama
- Faculty of Agriculture, University of Miyazaki, Miyazaki, 889-2192, Japan
| | - Koh Yasue
- Institute for Mountain Science, Shinshu University, Minami-minowa, 399-4598, Japan
| | - Yasuyuki Ohno
- Forest Research Institute, Hokkaido Research Organization, Bibai, 079-0198, Japan
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Haruhara M, Muta H, Ohtori Y, Yamagishi S, Terayama S. Proposal of quantification method of dynamic system reliability model of digital RPS using Markov state-transition model. J NUCL SCI TECHNOL 2023. [DOI: 10.1080/00223131.2023.2169379] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Masanobu Haruhara
- Cooperative Major in Nuclear Energy, Tokyo City University, Tokyo, Japan
| | - Hitoshi Muta
- Cooperative Major in Nuclear Energy, Tokyo City University, Tokyo, Japan
| | - Yasuki Ohtori
- Cooperative Major in Nuclear Energy, Tokyo City University, Tokyo, Japan
| | - Shohei Yamagishi
- Cooperative Major in Nuclear Energy, Tokyo City University, Tokyo, Japan
- Cooperative Major in Nuclear Energy, ITOCHU Techno-Solutions Corporation, Tokyo, Japan
| | - Shota Terayama
- Cooperative Major in Nuclear Energy, Tokyo City University, Tokyo, Japan
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Kishigami M, Matsuoka F, Maeno A, Yamagishi S, Abe H, Toki W. Yeast associated with flower longicorn beetle Leptura ochraceofasciata (Cerambycidae: Lepturinae), with implication for its function in symbiosis. PLoS One 2023; 18:e0282351. [PMID: 36947508 PMCID: PMC10032543 DOI: 10.1371/journal.pone.0282351] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Accepted: 02/13/2023] [Indexed: 03/23/2023] Open
Abstract
Wood is difficult for most animals to digest due to large amounts of indigestible polymers, but some wood-feeding insects are considered to be able to utilize it as food with the aid of microbial symbionts. Most members of flower longicorn beetles (Coleoptera: Cerambycidae: Lepturinae) feed on nectar and pollen of flowers as adults and wood as larvae. In some lepturines, associations with yeasts are known: female adults possess fungus-storing organs (termed mycetangia) at ovipositors, and larvae also possess such organs (termed mycetomes) in their midguts to carry the associated yeasts. Despite the high diversity of Lepturinae in the world, lepturine-yeast associations, such as the consistency of associated yeasts among the beetle's developmental stages and ecological function of yeast symbionts, have been poorly documented. Here, we investigated the yeast symbiont of the Japanese common lepturine Leptura ochraceofasciata. X-ray computed microtomography revealed that a pair of tube-like, S-shaped mycetangia was located at the basal part of the ovipositor and that a muscle bundle joined the apex of the mycetangium to spiculum ventrale of sternum VIII. All female adults harbored only one yeast species, Scheffersomyces insectosa, in the mycetangia. All larvae harbored S. insectosa exclusively in the mycetomes. Scheffersomyces insectosa was also recovered from surfaces of eggs. Scheffersomyces insectosa assimilated wood-associated sugars including xylose, cellobiose, and xylan in culture. These results suggest the intimate association between L. ochraceofasciata and S. insectosa: S. insectosa is transmitted from the mother to offspring during oviposition and may be related to larval growth in wood.
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Affiliation(s)
- Mako Kishigami
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Aichi, Japan
| | - Fumiaki Matsuoka
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Aichi, Japan
| | - Akiteru Maeno
- National Institute of Genetics, Mishima, Shizuoka, Japan
| | | | - Hisashi Abe
- Forestry and Forest Research Institute, Tsukuba, Ibaraki, Japan
| | - Wataru Toki
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Aichi, Japan
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Ide K, Shinohara M, Yamagishi S, Endo A, Nishifuji K, Tochio T. Kestose supplementation exerts bifidogenic effect within fecal microbiota and increases fecal butyrate concentration in dogs. J Vet Med Sci 2019; 82:1-8. [PMID: 31761826 PMCID: PMC6983673 DOI: 10.1292/jvms.19-0071] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Kestose, a fructooligosaccharide (FOS) with one fructose monomer linked to sucrose, is a key component of the prebiotic activity of FOS. This study aimed to evaluate the prebiotic potential
of Kestose in terms of the impact on population change in the intestinal microbiota and fecal short-chain fatty acid (SCFA) concentration in dogs. Kestose 2 g per dog was administered daily
with conventional diet to 6 healthy, adult beagle dogs for 8 weeks followed by 4 weeks of follow-up period without Kestose supplementation. Fresh fecal samples were obtained before and every
4 weeks until the end of the follow-up period. Genomic DNA extracted from the fecal samples was subjected to 16S rRNA gene analysis using next generation sequencer and to quantitative
polymerase chain reaction (qPCR). Fecal acetate, propionate, butyrate, lactate and ethanol concentrations were measured by high-performance liquid chromatography. 16S rRNA gene analysis and
qPCR showed increasing trend of genus Bifidobacterium after Kestose supplementation while genera Bacteroides and Sutterella decreased.
Clostridium perfringens decreased below the detection limit within first 4 weeks after starting Kestose supplementation. Fecal butyrate concentration was significantly
increased at week 8 and returned to the base level after 4 weeks of the washing period. To the best of our knowledge, this is the first study to reveal effect of Kestose on the populational
changes in fecal microbiota and fecal butyrate concentration in dogs.
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Affiliation(s)
- Kaori Ide
- Tokyo University of Agriculture and Technology, 3-5-8 Saiwai, Fuchu, Tokyo 183-8509, Japan
| | - Mikako Shinohara
- B Food Science Co., Ltd., 24-12 Kitahama, Chita, Aichi 478-0046, Japan
| | - Shohei Yamagishi
- Tokyo University of Agriculture and Technology, 3-5-8 Saiwai, Fuchu, Tokyo 183-8509, Japan
| | - Akihito Endo
- Tokyo University of Agriculture, 196 Yasaka, Abashiri, Hokkaido 099-2493, Japan
| | - Koji Nishifuji
- Tokyo University of Agriculture and Technology, 3-5-8 Saiwai, Fuchu, Tokyo 183-8509, Japan
| | - Takumi Tochio
- B Food Science Co., Ltd., 24-12 Kitahama, Chita, Aichi 478-0046, Japan
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NAGASAWA H, Ueda S, Yabuuchi J, Kobayashi T, Kanaguchi Y, Takahashi K, Yamagishi S, Suzuki Y. SAT-283 Chronic inflammation, but not AGEs, is involved in the development of vascular calcification in hemodialysis patients. Kidney Int Rep 2019. [DOI: 10.1016/j.ekir.2019.05.320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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Abstract
Pigment epithelium-derived factor (PEDF) is a glycoprotein with complex neuroprotective, anti-angiogenic, and anti-inflammatory properties, all of which could potentially be exploited as a therapeutic option for vascular complications in diabetes. We have previously shown that PEDF-derived synthetic peptide, P5-3 (FIFVLRD) has a comparable ability with full PEDF protein to inhibit rat corneal neovascularization induced by chemical cauterization. However, the effects of PEDF peptide on experimental diabetic nephropathy remain unknown. To address the issue, we modified P5-3 to stabilize and administered the modified peptide (d-Lys-d-Lys-d-Lys-Gln-d-Pro-P5-3-Cys-amide, 0.2 nmol/day) or vehicle to streptozotocin-induced diabetic rats (STZ-rats) intraperitoneally by an osmotic mini pump for 2 weeks. We further examined the effects of modified peptide on human proximal tubular cells. Renal PEDF expression was decreased in STZ-rats. Although the peptide administration did not affect blood glucose or blood pressure, it decreased urinary excretion levels of 8-hydroxy-2'-deoxyguanosine, an oxidative stress marker, and reduced plasminogen activator inhibitor-1 (PAI-1) gene expression, and suppressed glomerular expansion in the diabetic kidneys. High glucose or advanced glycation end products stimulated oxidative stress generation and PAI-1 gene expression in tubular cells, all of which were significantly suppressed by 10 nM modified P5-3 peptide. Our present study suggests that PEDF-derived synthetic modified peptide could protect against experimental diabetic nephropathy and inhibit tubular cell damage under diabetes-like conditions through its anti-oxidative properties. Supplementation of modified P5-3 peptide may be a novel therapeutic strategy for diabetic nephropathy.
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Affiliation(s)
- Y Ishibashi
- Department of Pathophysiology and Therapeutics of Diabetic Vascular Complications, Kurume University School of Medicine, Kurume, Japan
| | - T Matsui
- Department of Pathophysiology and Therapeutics of Diabetic Vascular Complications, Kurume University School of Medicine, Kurume, Japan
| | - J Taira
- Department of Chemistry, Kurume University School of Medicine, Kurume, Japan
| | - Y Higashimoto
- Department of Chemistry, Kurume University School of Medicine, Kurume, Japan
| | - S Yamagishi
- Department of Pathophysiology and Therapeutics of Diabetic Vascular Complications, Kurume University School of Medicine, Kurume, Japan
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Nakamura K, Yamagishi S, Matsui T, Yoshida T, Imaizumi T, Makino T, Shimizu T, Inoue H. Acarbose, an α-Glucosidase Inhibitor, Decreases Aortic Gene Expression and Serum Levels of Monocyte Chemoattractant Protein-1 in Fructose-fed Rats. J Int Med Res 2016; 34:525-30. [PMID: 17133782 DOI: 10.1177/147323000603400510] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Insulin resistance is one of the determinants of post-prandial hyperglycaemia. Recently, acarbose, an α-glucosidase inhibitor that delays the absorption of carbohydrates from the small intestine, has been found to reduce the incidence of cardiovascular disease in patients with impaired glucose tolerance or diabetes. However, the molecular mechanism by which acarbose inhibits cardiovascular events remains unknown. In this study, we examined whether oral administration of acarbose could suppress expression of monocyte chemoattractant protein-1 (MCP-1) in fructose-fed rats, a widely used animal model of insulin resistance. Serum MCP-1 levels were elevated in fructose-fed rats after 4 weeks. Acarbose treatment for 4 weeks reduced the fructose-induced elevation of serum MCP-1 levels. Acarbose treatment for 8 weeks decreased MCP-1 mRNA levels in the aortae of fructose-fed rats. These results suggest that the cardioprotective effects of acarbose could be due, at least in part, to the suppression of MCP-1 expression.
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Affiliation(s)
- K Nakamura
- Department of Internal Medicine, Murume University School of Medicine, Kurume, Japan; 2Department of Dermatology, Faculty of Medicine, University of Toyama, Toyama, Japan
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Matsui T, Yamagishi S, Nakamura K, Inoue H, Takeuchi M. Nifedipine, a Calcium-channel Blocker, Inhibits Advanced Glycation End-product-induced Expression of Monocyte Chemoattractant Protein-1 in Human Cultured Mesangial Cells. J Int Med Res 2016; 35:107-12. [PMID: 17408061 DOI: 10.1177/147323000703500111] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
The interaction between advanced glycation end-products (AGEs) and their receptors mediates the progressive alteration in renal architecture and loss of renal function in diabetic nephropathy. This study investigated whether nifedipine, a widely used anti-hypertensive drug, suppresses expression of monocyte chemoattractant protein-1 (MCP-1), a chemokine that mediates the recruitment of monocytes to inflammatory sites, in AGE-exposed human cultured mesangial cells. Cells were treated with 100 μg/ml AGE-bovine serum albumin (BSA) or non-glycated BSA in the presence or absence of 1 μM nifedipine or 50 nM diphenylene iodonium, an inhibitor of reduced nicotinamide-adenine dinucleotide phosphate oxidase, for 4 or 24 h. Expression of MCP-1 mRNA was measured using a semi-quantitative reverse transcription-polymerase chain reaction; MCP-1 protein production was measured using an enzyme-linked immunosorbent assay. AGEs significantly increased both MCP-1 mRNA expression and protein production in mesangial cells; this increase was blocked by both nifedipine and diphenylene iodonium. These results suggest that nifedipine could play a protective role against early diabetic nephropathy by suppressing MCP-1 overexpression via blockade of AGE signalling in mesangial cells.
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Affiliation(s)
- T Matsui
- Department of Internal Medicine, Kurume University School of Medicine, Kurume, Japan
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Ishibashi Y, Matsui T, Yamagishi S. Tofogliflozin, A Highly Selective Inhibitor of SGLT2 Blocks Proinflammatory and Proapoptotic Effects of Glucose Overload on Proximal Tubular Cells Partly by Suppressing Oxidative Stress Generation. Horm Metab Res 2016; 48:191-5. [PMID: 26158396 DOI: 10.1055/s-0035-1555791] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Ninety percent of glucose filtered by the glomerulus is reabsorbed by a sodium-glucose cotransporter 2 (SGLT2), which is mainly expressed on S1 and S2 segment of renal proximal tubules. Since SGLT-2-mediated glucose reabsorption is increased under diabetic conditions, selective inhibition of SGLT2 is a potential therapeutic target for the treatment of diabetes. We have recently shown that an inhibitor of SGLT2 has anti-inflammatory and antifibrotic effects on experimental diabetic nephropathy partly by suppressing advanced glycation end products formation and oxidative stress generation in the kidney. However, the direct effects of SGLT2 inhibitor on tubular cell damage remain unclear. In this study, we investigated the effects of tofogliflozin, a highly selective inhibitor of SGLT2 on oxidative stress generation, inflammatory and proapoptotic reactions in cultured human proximal tubular cells exposed to high glucose. Tofogliflozin dose-dependently suppressed glucose entry into tubular cells. High glucose exposure (30 mM) for 4 and 24 h significantly increased oxidative stress generation in tubular cells, which were suppressed by the treatment of tofogliflozin or an antioxidant N-acetylcysteine (NAC). Monocyte chemoattractant protein-1 (MCP-1) gene expression and apoptotic cell death were induced by 4 h- and 8 day-exposure to high glucose, respectively, both of which were also blocked by tofogliflozin or NAC. The present study suggests that SGLT2-mediated glucose entry into tubular cells could stimulate oxidative stress and evoke inflammatory and proapoptotic reactions in this cell type. Blockade of glucose reabsorption in tubular cells by SGLT2 inhibitor might exert beneficial effects on tubulointerstitial damage in diabetic nephropathy.
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Affiliation(s)
- Y Ishibashi
- Department of Pathophysiology and Therapeutics of Diabetic Vascular Complications, Kurume University School of Medicine, Kurume, Japan
| | - T Matsui
- Department of Pathophysiology and Therapeutics of Diabetic Vascular Complications, Kurume University School of Medicine, Kurume, Japan
| | - S Yamagishi
- Department of Pathophysiology and Therapeutics of Diabetic Vascular Complications, Kurume University School of Medicine, Kurume, Japan
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Ojima A, Matsui T, Nishino Y, Nakamura N, Yamagishi S. Empagliflozin, an Inhibitor of Sodium-Glucose Cotransporter 2 Exerts Anti-Inflammatory and Antifibrotic Effects on Experimental Diabetic Nephropathy Partly by Suppressing AGEs-Receptor Axis. Horm Metab Res 2015; 47:686-92. [PMID: 25611208 DOI: 10.1055/s-0034-1395609] [Citation(s) in RCA: 160] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Advanced glycation end products (AGEs) and receptor RAGE play a role in diabetic nephropathy. We have previously shown that increased glucose uptake into proximal tubular cells via sodium-glucose cotransporter 2 (SGLT2) stimulates oxidative stress generation and RAGE expression, thereby exacerbating the AGE-induced apoptosis in this cell type. However, the protective role of SGLT2 inhibition against the AGE-RAGE-induced renal damage in diabetic animals remains unclear. In this study, we investigated the effects of empagliflozin, SGLT2 inhibitor on AGE-RAGE axis, inflammatory and fibrotic reactions, and tubular injury in the kidney of streptozotocin-induced diabetic rats.Administration of empagliflozin for 4 weeks significantly improved hyperglycemia and HbA1c, and decreased expression levels of AGEs, RAGE, 8-hydroxydeoxyguanosine (8-OHdG), and F4/80, markers of oxidative stress and macrophages, respectively, in the diabetic kidney. Although empagliflozin did not reduce albuminuria, it significantly decreased urinary excretion levels of 8-OHdG and L-fatty acid binding protein, a marker of tubular injury. Moreover, inflammatory and fibrotic gene expression such as monocyte chemoattractant protein-1, intercellular adhesion molecule-1, plasminogen activator inhibitor-1, transforming growth factor-β, and connective tissue growth factor was enhanced in the diabetic kidney, all of which were prevented by empagliflozin. The present study suggests that empagliflozin could inhibit oxidative, inflammatory and fibrotic reactions in the kidney of diabetic rats partly via suppression of the AGE-RAGE axis. Blockade of the increased glucose uptake into renal proximal tubular cells by empagliflozin might be a novel therapeutic target for tubulointerstitial damage in diabetic nephropathy.
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Affiliation(s)
- A Ojima
- Department of Pathophysiology and Therapeutics of Diabetic Vascular Complications, Kurume University School of Medicine, Kurume, Japan
| | - T Matsui
- Department of Pathophysiology and Therapeutics of Diabetic Vascular Complications, Kurume University School of Medicine, Kurume, Japan
| | - Y Nishino
- Department of Pathophysiology and Therapeutics of Diabetic Vascular Complications, Kurume University School of Medicine, Kurume, Japan
| | - N Nakamura
- Department of Pathophysiology and Therapeutics of Diabetic Vascular Complications, Kurume University School of Medicine, Kurume, Japan
| | - S Yamagishi
- Department of Pathophysiology and Therapeutics of Diabetic Vascular Complications, Kurume University School of Medicine, Kurume, Japan
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Ojima A, Matsui T, Nakamura N, Higashimoto Y, Ueda S, Fukami K, Okuda S, Yamagishi S. DNA aptamer raised against advanced glycation end products (AGEs) improves glycemic control and decreases adipocyte size in fructose-fed rats by suppressing AGE-RAGE axis. Horm Metab Res 2015; 47:253-8. [PMID: 25105541 DOI: 10.1055/s-0034-1385904] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Advanced glycation end products (AGEs) decrease adiponectin expression and suppress insulin signaling in cultured adipocytes through the interaction with a receptor for AGEs (RAGE) via oxidative stress generation. We have recently found that high-affinity DNA aptamer directed against AGE (AGE-aptamer) prevents the progression of experimental diabetic nephropathy by blocking the harmful actions of AGEs in the kidney. This study examined the effects of AGE-aptamer on adipocyte remodeling, AGE-RAGE-oxidative stress axis, and adiponectin expression in fructose-fed rats. Although AGE-aptamer treatment by an osmotic mini pump for 8 weeks did not affect serum insulin levels, it significantly decreased average fasting blood glucose and had a tendency to inhibit body weight gain in fructose-fed rats. Furthermore, AGE-aptamer significantly suppressed the increase in adipocyte size and prevented the elevation in AGEs, RAGE, and an oxidative stress marker, 8-hydroxydeoxyguanosine (8-OHdG), levels in adipose tissues of fructose-fed rats at 14-week-old, while it restored the decrease in adiponectin mRNA levels. Our present study suggests that AGE-aptamer could improve glycemic control and prevent adipocyte remodeling in fructose-fed rats partly by suppressing the AGE-RAGE-mediated oxidative stress generation. AGE-aptamer might be a novel therapeutic strategy for fructose-induced metabolic derangements.
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Affiliation(s)
- A Ojima
- Department of Pathophysiology and Therapeutics of Diabetic Vascular Complications, Kurume University School of Medicine, Kurume, Japan
| | - T Matsui
- Department of Pathophysiology and Therapeutics of Diabetic Vascular Complications, Kurume University School of Medicine, Kurume, Japan
| | - N Nakamura
- Department of Pathophysiology and Therapeutics of Diabetic Vascular Complications, Kurume University School of Medicine, Kurume, Japan
| | - Y Higashimoto
- Department of Chemistry, Kurume University School of Medicine, Kurume, Japan
| | - S Ueda
- Department of Medicine, Kurume University School of Medicine, Kurume, Japan
| | - K Fukami
- Department of Medicine, Kurume University School of Medicine, Kurume, Japan
| | - S Okuda
- Department of Medicine, Kurume University School of Medicine, Kurume, Japan
| | - S Yamagishi
- Department of Pathophysiology and Therapeutics of Diabetic Vascular Complications, Kurume University School of Medicine, Kurume, Japan
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Takeuchi M, Sakasai-Sakai A, Takata T, Ueda T, Takino J, Tsutsumi M, Hyogo H, Yamagishi S. Serum levels of toxic AGEs (TAGE) may be a promising novel biomarker in development and progression of NASH. Med Hypotheses 2015; 84:490-3. [PMID: 25697114 DOI: 10.1016/j.mehy.2015.02.002] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2014] [Accepted: 02/04/2015] [Indexed: 12/13/2022]
Abstract
Nonalcoholic fatty liver disease (NAFLD) ranges from simple steatosis to nonalcoholic steatohepatitis (NASH), leads to fibrosis and potentially cirrhosis, liver failure, and hepatocellular carcinoma, and is one of the most common causes of liver disease worldwide. NAFLD has also been implicated in other medical conditions such as insulin resistance, obesity, metabolic syndrome, hyperlipemia, hypertension, cardiovascular disease, and diabetes. Continuous hyperglycemia has been implicated in the pathogenesis of diabetic micro- and macro-vascular complications via various metabolic pathways, and numerous hyperglycemia-induced metabolic and hemodynamic conditions exist, including the increased generation of various types of advanced glycation end-products (AGEs). We recently demonstrated that glyceraldehyde-derived AGEs (Glycer-AGEs), the predominant components of toxic AGEs (TAGE), played an important role in the pathogenesis of angiopathy in diabetic patients. Moreover, a growing body of evidence suggests that the interaction between TAGE and the receptor for AGEs may alter intracellular signaling, gene expression, and the release of pro-inflammatory molecules and also elicits the generation of oxidative stress in numerous types of cells including hepatocytes and hepatic stellate cells. Serum levels of TAGE were significantly higher in NASH patients than in those with simple steatosis and healthy controls. Moreover, serum levels of TAGE inversely correlated with adiponectin (adiponectin is produced by adipose tissue and is an anti-inflammatory adipokine that can increase insulin sensitivity). Furthermore, immunohistochemical staining of TAGE showed intense staining in the livers of patients with NASH. Serum levels of TAGE may be a useful biomarker for discriminating NASH from simple steatosis. The administration of atorvastatin (10 mg daily) for 12 months significantly improved NASH-related metabolic parameters and significantly decreased serum levels of TAGE. The steatosis grade and NAFLD activity score were also significantly improved. These results demonstrated that atorvastatin decreased the serum levels of TAGE in NASH patients with dyslipidemia and suggest the usefulness of TAGE as a biomarker for the attenuation of NASH. Serum levels of TAGE were significantly higher in non-B or non-C hepatocellular carcinoma (NBNC-HCC) patients than in NASH subjects without HCC or control subjects. TAGE may be involved in the pathogenesis of NBNC-HCC, and could, therefore, be a biomarker that could discriminate NBNC-HCC from NASH. We propose that serum levels of TAGE are promising novel targets for the diagnosis of and therapeutic interventions against NASH.
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Affiliation(s)
- M Takeuchi
- Department of Advanced Medicine, Medical Research Institute, Kanazawa Medical University, Ishikawa, Japan.
| | - A Sakasai-Sakai
- Department of Advanced Medicine, Medical Research Institute, Kanazawa Medical University, Ishikawa, Japan
| | - T Takata
- Department of Advanced Medicine, Medical Research Institute, Kanazawa Medical University, Ishikawa, Japan
| | - T Ueda
- Department of Advanced Medicine, Medical Research Institute, Kanazawa Medical University, Ishikawa, Japan
| | - J Takino
- Laboratory of Biochemistry, Faculty of Pharmaceutical Sciences, Hiroshima International University, Hiroshima, Japan
| | - M Tsutsumi
- Department of Hepatology, Kanazawa Medical University, Ishikawa, Japan
| | - H Hyogo
- Department of Gastroenterology and Metabolism, Hiroshima University Hospital, Hiroshima, Japan
| | - S Yamagishi
- Department of Pathophysiology and Therapeutics of Diabetic Vascular Complications, Kurume University School of Medicine, Fukuoka, Japan
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Ishibe A, Ota M, Kanazawa A, Watanabe J, Tatsumi K, Watanabe K, Godai T, Yamagishi S, Fujii S, Ichikawa Y, Kunisaki C, Endo I. Nutritional management of anastomotic leakage after colorectal cancer surgery using elemental diet jelly. Hepatogastroenterology 2015; 62:30-33. [PMID: 25911862] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
BACKGROUND/AIMS Anastomotic leakage is major complication of colorectal surgery. Total parenteral nutrition (TPN) and fasting are conservative treatments for leakage in the absence of peritonitis in Japan. Elemental diet (ED) jelly is a completely digested formula and is easily absorbed without secretion of digestive juices. The purpose of this study was to assess the safety of ED jelly in management of anastomotic leakage. METHODOLOGY Six hundred and two patients who underwent elective surgery for left side colorectal cancer from January 2008 to December 2011 were included in the study. Pelvic drainage was performed for all patients. Sixty-three (10.5%) patients were diagnosed with an anastomotic leakage, and of these, 31 (5.2%) without diverting stoma were enrolled in this study. RESULTS Sixteen patients received TPN (TPN group) and 15 patients received ED jelly (ED group). The duration of intravenous infusion was significantly shorter in the ED group than in the TPN group (15 days versus 25 days, P= 0.008). In the TPN group, catheter infection was occurred in 2 patients who required re-insertion of the catheter. CONCLUSION Conservative management of anastomotic leakage after colorectal surgery with ED jelly appears to be a safe and useful approach.
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Ishibashi Y, Matsui T, Ueda S, Fukami K, Okuda S, Ohta H, Yamagishi S. Bazedoxifene blocks AGEs-RAGE-induced superoxide generation and MCP-1 level in endothelial cells. Climacteric 2014; 18:426-30. [PMID: 25340263 DOI: 10.3109/13697137.2014.958073] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Advanced glycation endproducts (AGEs) and their receptor (RAGE) play a role in vascular complications in diabetes. We have previously shown that 17β-estradiol at 10 nmol/l, a nearly identical plasma concentration to that during mid-pregnancy, up-regulates RAGE expression in endothelial cells. The finding might suggest the involvement of 17β-estradiol in the deterioration of vascular complications in diabetes during pregnancy. However, the effects of the selective estrogen receptor modulator, bazedoxifene, on oxidative and inflammatory reactions in AGEs-exposed endothelial cells remain unknown. In this study, we addressed the issue. Ten nmol/l 17β-estradiol increased RAGE and monocyte chemoattractant protein-1 (MCP-1) gene and protein expression in human umbilical vein endothelial cells (HUVECs), both of which were blocked by 10 nmol/l bazedoxifene. Bazedoxifene at 10 nmol/l also significantly inhibited the AGEs-induced superoxide generation, RAGE and MCP-1 gene and protein expression in HUVECs. The present study suggests that blockade of the AGEs-RAGE axis by bazedoxifene might be a novel therapeutic target for preventing vascular damage in diabetes, especially in postmenopausal women.
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Affiliation(s)
- Y Ishibashi
- Department of Pathophysiology and Therapeutics of Diabetic Vascular Complications
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15
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Obara N, Ueda S, Yamagishi S, Nakayama Y, Taguchi K, Yokoro M, Fukami K, Okuda S. Involvement of DDAH-ADMA axis in AKI. Atherosclerosis 2014. [DOI: 10.1016/j.atherosclerosis.2014.05.720] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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16
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Ishibashi Y, Matsui T, Yamagishi S. Olmesartan blocks advanced glycation end products-induced vcam-1 gene expression in mesangial cells by restoring Angiotensin-converting enzyme 2 level. Horm Metab Res 2014; 46:379-83. [PMID: 24297485 DOI: 10.1055/s-0033-1361114] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Advanced glycation end products (AGEs) and their receptor (RAGE) system are involved in diabetic nephropathy. Angiotensin-converting enzyme 2 (ACE 2) plays a protective role against cardiovascular and renal injury by stimulating the production of angiotensin-(1-7) [Ang-(1-7)], an antagonist of angiotensin II (Ang II). However, effects of the AGEs-RAGE axis on ACE 2 expression in mesangial cells remain unknown. We examined here the role of ACE 2 in the AGEs-RAGE-induced mesangial cell damage and investigated whether olmesartan, one of the Ang II type 1 receptor blockers (ARB), prevented the deleterious effects of AGEs via restoration of ACE 2 and Ang-(1-7) level. AGEs significantly increased superoxide generation, upregulated RAGE mRNA level, and decreased ACE 2 gene expression and Ang-(1-7) production in mesangial cells, all of which were blocked by olmesartan, but not by a different type of ARB, azilsartan. An antioxidant, N-acetylcysteine or RAGE-antibodies also restored the decrease in ACE 2 mRNA level in AGEs-exposed mesangial cells. Moreover, olmesartan, but not azilsartan completely inhibited the AGEs-induced increase in vascular cell adhesion molecule-1 (VCAM-1) mRNA level in mesangial cells, which was abolished by the treatment with A-779, an antagonist of Ang-(1-7) receptor, Mas receptor. Our present study suggests that olmesartan could block the AGEs-induced VCAM-1 gene induction in mesangial cells by restoring the downregulated ACE 2 levels and subsequently stimulating the Ang-(1-7)-Mas receptor axis. Restoration of ACE 2 levels and blockade of renin-angiotensin system by olmesartan might be a promising strategy for the treatment of diabetic nephropathy.
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Affiliation(s)
- Y Ishibashi
- Department of Pathophysiology and Therapeutics of Diabetic Vascular Complications, Kurume University School of Medicine, Kurume, Japan
| | - T Matsui
- Department of Pathophysiology and Therapeutics of Diabetic Vascular Complications, Kurume University School of Medicine, Kurume, Japan
| | - S Yamagishi
- Department of Pathophysiology and Therapeutics of Diabetic Vascular Complications, Kurume University School of Medicine, Kurume, Japan
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17
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Tsuji T, Ishiguro Y, Nakui Y, Murata Y, Munakata A, Onozuka N, Fukui K, Suzuki S, Yamagishi S. A case of dissecting aortic aneurysm with cystic medial necrosis in systemic lupus erythematosus. Mod Rheumatol 2014; 11:238-41. [DOI: 10.3109/s101650170011] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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18
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Yamagishi S, Grundfest H. Contributions of various ions to the resting and action potentials of crayfish medial giant axons. J Membr Biol 2013; 5:345-65. [PMID: 24173164 DOI: 10.1007/bf01957351] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/1971] [Indexed: 11/28/2022]
Abstract
The membrane of crayfish medial giant axons is permeable at rest to ions in the rank K>Na>Ca>Cl. With K present, variation of the other ions has little or no effect, but with K absent the axon hyperpolarizes when Na is reduced or eliminated by replacement with Tris (slope ca. 30 mV/decade Na0). The hyperpolarization is independent of the presence of Cl or its absence (substitution with methanesulfonate or isethionate). The resistance increases progressively as Na is removed. These changes persist after the spike is blocked with tetrodotoxin. An increase in Ca causes depolarization (slope ca. 20 mV/decade) provided K, Na and Cl are all absent, but in the presence of Cl there is little or no change in membrane potential on increasing Ca to 150MM. The depolarization induced by Ca is associated with an increased resistance. Spike electrogenesis involves Ca activation as well as Na activation, but the after-depolarization at the end of the spike is due to a conductance increase for Ca. Two alternative equivalent circuits for the resting and active membrane are discussed.
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Affiliation(s)
- S Yamagishi
- Laboratory of Neurophysiology, Department of Neurology, College of Physicians and Surgeons, Columbia University, 10032, New York, New York
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19
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Kaneko K, Uematsu E, Takahashi Y, Tong B, Takino S, Wajiki Y, Kimura T, Yamashiro H, Kaneko Y, Iwaisaki H, Sugiyama T, Yamada T, Yamagishi S. Semen collection and polymerase chain reaction-based sex determination of black-headed and straw-necked ibis. Reprod Domest Anim 2013; 48:1001-5. [PMID: 23808530 DOI: 10.1111/rda.12200] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2013] [Accepted: 05/28/2013] [Indexed: 11/27/2022]
Abstract
This study aimed to develop a polymerase chain reaction (PCR)-based sexing and effective semen collection methods for black-headed and straw-necked ibis species. However, most birds are not sexually dimorphic, that is, the sexes appear similar. Therefore, the gender should be determined before semen collection. DNA was extracted from the blood samples of 11 black-headed and 4 straw-necked ibis. The sex was determined after PCR amplification of the EE0.6 region of W-chromosome. The PCR products were separated using gel electrophoresis. A single band indicated the presence of the EE0.6 region and that the individual was a female, while no band indicated that the individual was a male. Further, the single bands from seven specimens were amplified. Semen collection was performed by massage or a combination of massage with electro-ejaculation and was attempted during all four seasons. The semen was successfully collected in March from male straw-necked ibis using the massage method. Limited motility, viability and concentration of straw-necked ibis sperm were observed. The sperm length was 180 μm and that of the nucleus was 30 μm with acrosome located at the tip of the nucleus. Thus, the PCR-based sexing proved to be an accurate molecular sexing method for black-headed and straw-necked ibis. Furthermore, we successfully collected semen and observed the stained sperm nucleus and acrosome of the straw-necked ibis sperm. We propose that the use of this PCR methodology can be applied as a routine method for sex determination and semen collection in ibis species for future ecological research. However, considering our limited success, further studies on semen collection method are required.
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Affiliation(s)
- K Kaneko
- Faculty of Agriculture, Niigata University, Nishiku, Niigata, Japan
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20
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Ishibashi Y, Matsui T, Takeuchi M, Yamagishi S. Metformin inhibits advanced glycation end products (AGEs)-induced growth and VEGF expression in MCF-7 breast cancer cells by suppressing AGEs receptor expression via AMP-activated protein kinase. Horm Metab Res 2013; 45:387-90. [PMID: 23225247 DOI: 10.1055/s-0032-1331204] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Metformin use has been reported to decrease breast cancer incidence and mortality in diabetic patients. We have previously shown that advanced glycation end products (AGEs) and their receptor (RAGE) interaction stimulate growth and/or migration of pancreatic cancer and melanoma cells. However, effects of metformin on AGEs-RAGE axis in breast cancers remain unknown. We examined here whether and how metformin could block the AGEs-induced growth and vascular endothelial growth factor (VEGF) expression in MCF-7 breast cancer cells. Cell proliferation was measured with an electron coupling reagent WST-1 based colorimetric assay. Gene expression level was evaluated by real-time reverse-transcription polymerase chain reactions. AGEs significantly increased cell proliferation of MCF-7 cells, which was completely prevented by the treatment with 0.01 or 0.1 mM metformin or anti-RAGE antibodies. Furthermore, metformin at 0.01 mM completely suppressed the AGEs-induced upregulation of RAGE and VEGF mRNA levels in MCF-7 cells. An inhibitor of AMP-activated protein kinase, compound C significantly blocked the growth-inhibitory and RAGE and VEGF suppressing effects of metformin in AGEs-exposed MCF-7 cells. Our present study suggests that metformin could inhibit the AGEs-induced growth and VEGF expression in MCF-7 breast cancer cells by suppressing RAGE gene expression via AMP-activated protein kinase pathway. Metformin may protect against breast cancer expansion in diabetic patients by blocking the AGEs-RAGE axis.
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Affiliation(s)
- Y Ishibashi
- Department of Pathophysiology and Therapeutics of Diabetic Vascular Complications, Kurume University School of Medicine, Kurume, Japan
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21
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Ishibashi Y, Matsui T, Takeuchi M, Yamagishi S. Metformin inhibits advanced glycation end products (AGEs)-induced renal tubular cell injury by suppressing reactive oxygen species generation via reducing receptor for AGEs (RAGE) expression. Horm Metab Res 2012; 44:891-5. [PMID: 22864903 DOI: 10.1055/s-0032-1321878] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Advanced glycation end products (AGEs) and their receptor (RAGE) play a role in tubulointerstitial damage in diabetic nephropathy. Recently, metformin has been shown to ameliorate tubular injury both in cell culture and diabetic animal model. However, effects of metformin on AGEs-induced tubular cell apoptosis and damage remain unknown. We examined here whether and how metformin could block the AGEs-RAGE-elicited tubular cell injury in vitro. Gene expression level was evaluated by real-time reverse-transcription polymerase chain reactions. Reactive oxygen species (ROS) generation was measured with dihydroethidium staining. Apoptosis was evaluated by DNA fragmentation and annexin V expression level. AGEs upregulated RAGE mRNA levels and subsequently increased ROS generation and intercellular adhesion molecule-1, monocyte chemoattractant protein-1 and transforming growth factor-β gene expression in human renal proximal tubular cells, all of which were significantly blocked by the treatment of 0.01 and 0.1 mM metformin. Compound C, an inhibitor of AMP-activated protein kinase significantly blocked the effects of metformin on RAGE gene expression and ROS generation in AGEs-exposed tubular cells. Furthermore, metformin dose-dependently inhibited the AGEs-induced apoptotic cell death of tubular cells; 1 mM metformin completely suppressed the pro-apoptotic effects of AGEs in 2 different assay systems. Our present study suggests that metformin could inhibit the AGEs-induced apoptosis and inflammatory and fibrotic reactions in tubular cells probably by reducing ROS generation via suppression of RAGE expression through AMP-activated protein kinase activation. Metformin may protect against tubular cell injury in diabetic nephropathy by blocking the AGEs-RAGE-ROS axis.
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Affiliation(s)
- Y Ishibashi
- Department of Pathophysiology and Therapeutics of Diabetic Vascular Complications, Kurume University School of Medicine, Kurume, Japan
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22
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Ojima A, Matsui T, Maeda S, Takeuchi M, Yamagishi S. Glucose-dependent insulinotropic polypeptide (GIP) inhibits signaling pathways of advanced glycation end products (AGEs) in endothelial cells via its antioxidative properties. Horm Metab Res 2012; 44:501-5. [PMID: 22581648 DOI: 10.1055/s-0032-1312595] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Glucose-dependent insulinotropic polypeptide (GIP) is one of the incretins, a gut hormone secreted from K cells in the intestine in response to food intake. It could be a potential therapeutic target for the treatment of patients with type 2 diabetes. However, effects of GIP on vascular injury remain unknown. Since interaction of advanced glycation end products (AGEs) with their receptor RAGE has been shown to play a crucial role in vascular damage in diabetes, this study investigated whether and how GIP blocked the deleterious effects of AGEs on human umbilical vein endothelial cells (HUVECs). GIP receptor was expressed in HUVECs. GIP, an analogue of cyclic AMP or inhibitors of NADPH oxidase inhibited the AGE-induced reactive oxygen species (ROS) generation in HUVECs. Furthermore, GIP reduced both RAGE mRNA and protein levels in HUVECs. GLP-1 also blocked the AGE-induced increase in mRNA levels of vascular cell adhesion molecule-1 (VCAM-1) and plasminogen activator inhibitor-1 in HUVECs. In addition, an antioxidant N-acetylcysteine mimicked the effects of GIP on RAGE and VCAM-1 gene expression in HUVECs. Our present study suggests that GIP could block the signal pathways of AGEs in HUVECs by reducing ROS generation and subsequent RAGE expression probably via GIP receptor-cyclic AMP axis.
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Affiliation(s)
- A Ojima
- Department of Pathophysiology and Therapeutics of Diabetic Vascular Complications, Kurume University School of Medicine, Kurume, Japan
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23
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Pawankar R, Takizawa R, Yamagishi S, Saito H, Iikura Y, Yagi T. Novel Roles of Mast Cells in Modulating IgE-Mediated Allergic Inflammation. Int Arch Allergy Immunol 2012. [DOI: 10.1159/000053700] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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Shiga Y, Miura S, Mitsutake R, Yamagishi S, Saku K. Significance of plasma levels of pigment epithelium-derived factor as determined by multidetector row computed tomography in patients with mild chronic kidney disease and/or coronary artery disease. J Int Med Res 2011; 39:880-90. [PMID: 21819721 DOI: 10.1177/147323001103900322] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Little is known about the association between plasma levels of pigment epithelium-derived factor (PEDF), coronary artery disease (CAD) and/or chronic kidney disease (CKD). This study evaluated 289 consecutive patients with chest pain or at least one coronary risk factor who underwent coronary angiography using multidetector row computed tomography (MDCT). Presence of CAD and CKD, CAD severity (i.e. number of significantly stenosed coronary vessels, described as vessel disease [VD]), coronary calcification scores, visceral fat area (VFA), subcutaneous fat area on MDCT, and metabolic biomarkers were recorded. PEDF levels correlated significantly with sex, VFA, CKD presence/hyperuricaemia and high-density lipoprotein cholesterol levels. PEDF levels were closely associated with CKD and were significantly higher in CKD patients than in non-CKD patients, regardless of the presence of CAD. CKD patients with two-VD or three-VD had higher plasma PEDF levels than non-CKD patients with two-VD or three-VD. It is concluded that PEDF may be associated with CKD regardless of the presence of CAD.
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Affiliation(s)
- Y Shiga
- Department of Cardiology, Fukuoka University School of Medicine, Fukuoka, Japan
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Ishibashi Y, Matsui T, Takeuchi M, Yamagishi S. Sitagliptin augments protective effects of GLP-1 against advanced glycation end product receptor axis in endothelial cells. Horm Metab Res 2011; 43:731-4. [PMID: 21932180 DOI: 10.1055/s-0031-1284383] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Sitagliptin is a stable inhibitor of dipeptidyl peptidase-IV, a responsible enzyme that mainly inactivates glucagon-like peptide-1 (GLP-1), and now one of the widely used agents for the treatment of diabetes. However, effects of sitagliptin on vascular injury are largely unknown. Since advanced glycation end products (AGEs) and their receptor (RAGE) axis contribute to vascular damage in diabetes, we investigated here whether sitagliptin inhibits the AGE-RAGE-induced endothelial cell damage in vitro. Although effects of 10 pM GLP-1 or 0.5 μM sitagliptin monotherapy on RAGE gene and protein expression were modest, combination therapy completely blocked the AGE-induced increase in RAGE mRNA and protein levels in human umbilical vein endothelial cells (HUVEC). AGEs induced reactive oxygen species (ROS) generation and reduced endothelial nitric oxide synthase (eNOS) mRNA level in HUVEC, both of which were also completely blocked by the treatment with 10 pM GLP-1 and 0.5 μM sitagliptin, but not with GLP-1 or sitagliptin monotherapy. Further, anti-RAGE antibody restored the decrease in eNOS mRNA level in AGE-exposed HUVEC. The present study suggests that sitagliptin augments the effects of GLP-1 on eNOS mRNA level in AGE-exposed HUVEC by suppressing RAGE expression and subsequent ROS generation. Sitagliptin may work as a vasoprotecitve agent in diabetes by blocking the AGE-RAGE axis.
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Affiliation(s)
- Y Ishibashi
- Department of Pathophysiology and Therapeutics of Diabetic Vascular Complications, Kurume University School of Medicine, Kurume, Japan
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Ishibashi Y, Matsui T, Takeuchi M, Yamagishi S. Rosuvastatin blocks advanced glycation end products-elicited reduction of macrophage cholesterol efflux by suppressing NADPH oxidase activity via inhibition of geranylgeranylation of Rac-1. Horm Metab Res 2011; 43:619-24. [PMID: 21823057 DOI: 10.1055/s-0031-1283148] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Adenosine triphosphate-binding membrane cassette transporter A1 (ABCA1) and ABCG1 play a crucial role in macrophage cholesterol efflux, which is a novel therapeutic target for atherosclerosis. Advanced glycation end products (AGE) and their receptor RAGE axis is involved in accelerated atherosclerosis in diabetes as well. However, the role of AGE-RAGE axis in macrophage cholesterol efflux is not fully understood. We examined here whether AGE-RAGE axis could impair cholesterol efflux from human macrophage cells, THP-1 cells by suppressing ABCA1 and ABCG1 expression. We further investigated the effects of rosuvastatin on cholesterol efflux from AGE-exposed THP-1 cells. AGE increased reactive oxygen species generation in THP-1 cells, which was completely inhibited by rosuvastatin, anti-RAGE-antibody or diphenylene iodonium chloride (DPI), an inhibitor of NADPH oxidase. The antioxidative effect of rosuvastatin on AGE-exposed THP-1 cells was significantly prevented by geranylgeranyl pyrophosphate (GGPP). AGE decreased ABCA1 and ABCG1 mRNA levels, and subsequently reduced cholesterol efflux from THP-1 cells, which was prevented by GGPP. DPI mimicked the effects of rosuvastain. The results demonstrated that rosuvastatin could inhibit the AGE-induced reduction of THP-1 macrophage cholesterol efflux by suppressing NADPH oxidase activity via inhibition of geranylgeranylation of Rac-1. Our present study provides a novel beneficial aspect of rosuvastatin in diabetes; rosuvastain may prevent the development and progression of atherosclerosis in diabetes by not only reducing serum cholesterol level, but also by improving cholesterol efflux from foam cells of the arterial wall via blocking the harmful effects of AGE on macrophages.
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Affiliation(s)
- Y Ishibashi
- Department of Pathophysiology and Therapeutics of Diabetic Vascular Complications, Kurume University School of Medicine, Kurume, Fukuoka, Japan
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Miura K, Kitahara Y, Kajioka T, Takeuchi M, Yamagishi S. Combination therapy with nateglinide and telmisartan ameliorates insulin resistance in zucker Fatty rats by suppressing advanced glycation end product receptor axis. Horm Metab Res 2011; 43:226-8. [PMID: 20972939 DOI: 10.1055/s-0030-1267227] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Advanced glycation end products (AGEs) and their receptor (RAGE) have been shown to play a role in insulin resistance. We have previously shown that combination therapy with nateglinide (NAT) and telmisartan (TEL) improves postprandial metabolic derangements in Zucker fatty (ZF) rats, an animal model of insulin resistance with obesity. However, effects of combination therapy on insulin resistance remain unknown. We investigated here whether combination therapy with TEL and NAT could ameliorate insulin resistance in ZF rats by suppressing AGE-RAGE axis. NAT and/or TEL inhibited insulin receptor substrate-1 (IRS-1) serine phosphorylations at 307 and 636/639 residues in the liver of ZF rats. Further, combination therapy with NAT and TEL, but not each monotherapy alone, significantly restored the decrease in hepatic IRS-1 tyrosine phosphorylation in these animals. In addition, serum levels of AGEs, RAGE expression levels in the liver and hepatic AGE-RAGE index were decreased in NAT plus TEL-treated ZF rats. The present study suggests that combination therapy with NAT and TEL could ameliorate insulin resistance in ZF rats by suppressing the AGE-RAGE axis in the liver.
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Affiliation(s)
- K Miura
- Exploratory Research Laboratories, Ajinomoto Pharmaceuticals Co. Ltd., Kawasaki, Japan
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Miura K, Kitahara Y, Kajioka T, Takeuchi M, Yamagishi S. Combination Therapy with Nateglinide and Telmisartan Ameliorates Insulin Resistance in Zucker Fatty Rats by Suppressing Advanced Glycation End Product Receptor Axis. Horm Metab Res 2011; 43:e1. [PMID: 21082533 DOI: 10.1055/s-0030-1268483] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- K Miura
- Exploratory Research Laboratories, Ajinomoto Pharmaceuticals Co. Ltd., Kawasaki, Japan
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Abstract
Postprandial metabolic derangements are one of the risk factors of cardiovascular disease in humans. Insulin resistance and/or impaired early-phase insulin secretion are major determinants of postprandial metabolic derangements. In this study, we investigated the potential utility of combination therapy with vildagliptin, a dipeptidyl peptidase IV (DPP-IV) inhibitor and nateglinide, a rapid-onset/short-duration insulinotropic agent, for the treatment of postprandial metabolic derangements in Zucker Fatty (ZF) rats, an animal model of obesity with insulin resistance. ZF rats fed twice daily with or without high fat diet (HFD) were given vehicle, 50 mg/kg of nateglinide, 10 mg/kg of vildagliptin, or both for 6 weeks. Combination therapy with nateglinide and vildagliptin for 2 weeks ameliorated postprandial hyperglycemia, hypertriglyceridemia, and elevation of free fatty acid in ZF rats fed with HFD. 6-week treatment with nateglinide and vildagliptin not only increased hepatic levels of phosphorylated forkhead box protein 1A (FOXO1A), but also reduced triglyceride contents in the liver. Combination therapy also prevented the loss of pancreatic islet mass in ZF rats fed with HFD. These observations demonstrate that combination therapy with nateglinide and vildagliptin may improve postprandial metabolic derangements probably by ameliorating early phase of insulin secretion and hepatic insulin resistance, respectively, in ZF rats fed with HFD. Since combination therapy with nateglinide and vildagliptin restored the decrease in pancreatic beta cell mass, our present findings suggest that combination therapy could be a promising therapeutic strategy for postprandial dysmetabolism associated with obese and insulin resistance.
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Affiliation(s)
- K Miura
- Pharmaceutical Research Laboratories, Ajinomoto, Kawasaki, Japan
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Kawaguchi T, Yamagishi S, Sata M. Branched-chain amino acids and pigment epithelium-derived factor: novel therapeutic agents for hepatitis c virus-associated insulin resistance. Curr Med Chem 2010; 16:4843-57. [PMID: 19929783 DOI: 10.2174/092986709789909620] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2009] [Accepted: 11/24/2009] [Indexed: 01/13/2023]
Abstract
Recent clinical studies have shown that patients with chronic liver disease are insulin resistant. Of all etiologies of chronic liver disease including non-alcoholic fatty liver disease, the one that causes the most sever insulin resistance is hepatitis C virus (HCV) infection. Since insulin resistance promotes inflammatory and fibrogenic reactions in the liver, thus leading to the development of liver cirrhosis and hepatocellular carcinoma (HCC) in patients with HCV infection, amelioration of insulin sensitivity may inhibit the progression of HCV-associated liver disease, and could improve the survival of these patients. HCV directly causes insulin resistance through HCV core protein-elicited proteasomal degradation of insulin receptor substrates and subsequent inactivation of intracellular insulin signaling molecules such as Akt. Furthermore, tumor necrosis factor-alpha (TNF-alpha) and/or triglyceride accumulation-induced nuclear factor-kappaB (NF-kappaB) activation in the liver is shown to play a role in insulin resistance in patients with HCV-related chronic liver disease as well. We, along with others, have recently found that branched-chain amino acids (BCAAs) and pigment epithelium-derived factor (PEDF) could improve the HCV-associated insulin resistance via suppression of NF-kappaB and preservation of insulin signaling pathway. In this review, we discuss the mechanisms for the actions of BCAAs and PEDF, and their clinical implications in insulin resistance of chronic liver disease in patients with HCV infection. We also discuss here which chemical structures could contribute to insulin-sensitization in patients with HCV infection.
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Affiliation(s)
- T Kawaguchi
- Department of Digestive Disease Information & Research, Kurume University School of Medicine, 67 Asahi-machi, Kurume 830-0011, Japan.
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Ichikawa Y, Goto A, Hirokawa S, Kijima M, Ishikawa T, Chishima T, Suwa H, Yamamoto H, Yamagishi S, Osada S, Ota M, Fujii S. Allergic Reactions to Oxaliplatin in a Single Institute in Japan. Jpn J Clin Oncol 2009; 39:616-20. [DOI: 10.1093/jjco/hyp070] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Zhao Y, Makino T, Honda A, Shimizu H, Yamagishi S, Shimizu T. Carebastine, an H1-receptor antagonist, suppresses the expression of macrophage migration inhibitory factor. Clin Exp Dermatol 2008; 33:785-7. [DOI: 10.1111/j.1365-2230.2008.02843.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Yamagishi S, Matsui T, Nakamura K. Possible link of food-derived advanced glycation end products (AGEs) to the development of diabetes. Med Hypotheses 2008; 71:876-8. [PMID: 18783891 DOI: 10.1016/j.mehy.2008.07.034] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2008] [Revised: 07/13/2008] [Accepted: 07/16/2008] [Indexed: 11/28/2022]
Abstract
China Da Qing diabetes prevention study has recently shown that group-based lifestyle interventions over six years can prevent or delay the development of diabetes in patients with impaired glucose tolerance (IGT) for up to 14 years after the active intervention. These findings suggest the sustained beneficial effects of lifestyle interventions to prevent diabetes in at-risk patients for diabetes. Therefore, the clinical study suggests that so-called 'metabolic memory' is involved in the development of diabetes. Potential mechanisms for propagating this 'metabolic memory' are the non-enzymatic glycation of proteins. The formation and accumulation of advanced glycation end products (AGEs) have been known to progress at an accelerated rate under diabetes, and there is accumulating evidence that AGEs play a role in the development of diabetes by inducing islet beta cell damage and/or insulin resistance. Further, there are several animal studies to suggest that dietary AGEs are involved in insulin resistance, visceral obesity and the development of diabetes. These findings led us to speculate that the long-term beneficial influence of early lifestyle interventions on the development of diabetes could be ascribed, at least in part, to their inhibitory effects on AGEs. That is, intake of food-derived AGEs may be suppressed in the lifestyle intervention group, which could reduce the risk for the development of diabetes in high-risk patients with IGT. Therefore, it is an interesting issue to clarify whether food-derived AGEs are actually restricted during the active intervention period and if circulating or tissue AGE levels at the closure of the China Da Qing diabetes prevention study could predict the risk for the development of diabetes 14 years after the trial. This additional, clinical investigation may provide us more information about whether restriction of food-derived AGEs is beneficial for the prevention of the development of diabetes in high-risk patients and may be a novel therapeutic target to prevent diabetes and its related complications.
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Affiliation(s)
- S Yamagishi
- Department of Pathophysiology and Therapeutics of Diabetic Vascular Complications, Kurume University School of Medicine, Kurume 830-0011, Japan.
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Yoshida T, Yamagishi S, Nakamura K, Matsui T, Imaizumi T, Takeuchi M, Koga H, Ueno T, Sata M. Pigment epithelium-derived factor (PEDF) ameliorates advanced glycation end product (AGE)-induced hepatic insulin resistance in vitro by suppressing Rac-1 activation. Horm Metab Res 2008; 40:620-5. [PMID: 18792873 DOI: 10.1055/s-0028-1083785] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Advanced glycation end products (AGEs) could be implicated in insulin resistance. However, the molecular mechanisms underlying this are not fully understood. Since pigment epithelium-derived factor (PEDF) blocks the AGE-signaling pathways, we examined here whether and how PEDF improves insulin resistance in AGE-exposed hepatoma cells, Hep3B cells. Proteins were extracted from Hep3B cells, immunoprecipitated with or without insulin receptor substrate-1 (IRS-1) antibodies, and subjected to Western blot analysis. Glycogen synthesis was measured using [ (14)C]-d-glucose. AGE induced Rac-1 activation and increased phosphorylation of IRS-1 at serine-307 residues, JNK, c-JUN, and IkappaB kinase in association with decreased IkappaB levels in Hep3B cells. PEDF or overexpression of dominant negative Rac-1 blocked these effects of AGE on Hep3B cells. Further, AGEs decreased tyrosine phosphorylation of IRS-1, and subsequently reduced the association of p85 subunit of phosphatidylinositol 3-kinase with IRS-1 and glycogen synthesis in insulin-exposed Hep3B cells, all of which were inhibited by PEDF. Our present study suggests that PEDF could improve the AGE-elicited insulin resistance in Hep3B cells by inhibiting JNK- and IkappaB kinase-dependent serine phosphorylation of IRS-1 via suppression of Rac-1 activation. PEDF may play a protective role against hepatic insulin resistance in diabetes.
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Affiliation(s)
- T Yoshida
- Department of Medicine, Kurume University School of Medicine, Kurume, Japan
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35
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Yamagishi S, Matsui T, Nakamura K. Possible involvement of tobacco-derived advanced glycation end products (AGEs) in an increased risk for developing cancers and cardiovascular disease in former smokers. Med Hypotheses 2008; 71:259-61. [PMID: 18448262 DOI: 10.1016/j.mehy.2008.03.020] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2008] [Revised: 03/01/2008] [Accepted: 03/07/2008] [Indexed: 11/21/2022]
Abstract
Tobacco smoking is one of the strongest risk factors for various disorders such as lung cancers and cardiovascular disease (CVD). Further, former smokers remain at an increased risk for developing lung cancers and CVD even years after they stop smoking. These observation suggest that expression levels of some of the genes related to tobacco smoking may not return to levels similar to never smokers and could be permanently altered despite prolonged smoking cessation, thereby being involved in the development of lung cancers and CVD. The modification, aggregation, and deposition of proteins are a prominent part of many pathological processes and can play a direct role in tissue damage. Advanced glycation end products (AGEs) have been shown to play a role in the development of many of the pathological sequelae of aging and diabetes such as CVD and cancer growth and metastasis. Moreover, there are several papers to show that tobacco smoke is a source of toxic reactive glycation products. Further, recent epidemiological and prospective data have supported the concept of 'metabolic memory', a long-term influence of previous hyperglycemia on the development of CVD in diabetes. Potential mechanism for propagating this 'memory' is considered to be the non-enzymatic glycation of proteins because the process of formation and accumulation of AGEs are most compatible with the theory. Therefore, it is conceivable that tobacco-derived AGEs are also involved in the increased risk for developing cancers and CVD in former smokers. In this paper, we would like to propose the possible ways of testing our hypotheses. Are tissue levels of AGEs still higher in former smokers, compared with age-, sex- and other confounders-matched non-smokers? If the answer is yes, are the tissue levels of AGEs following smoking cessation decreased? If we examine the effects of smoking cessation as a function of years since quitting, is the extent of decrease in tissue AGEs levels parallel to that of risk reduction for developing cancers and CVD? Further, are genes that are permanently altered despite prolonged smoking cessation identical to those that regulated by AGEs? These investigations could clarify whether tobacco-derived AGEs are involved in sustained tissue injury in former smokers.
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Affiliation(s)
- S Yamagishi
- Department of Medicine, Kurume University School of Medicine, 67 Asahi-machi, Kurume 830-0011, Japan.
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Yoshida T, Yamagishi S, Matsui T, Nakamura K, Ueno T, Takeuchi M, Sata M. Telmisartan, an Angiotensin II Type 1 Receptor Blocker, Inhibits Advanced Glycation End-product (AGE)-elicited Hepatic Insulin Resistance via Peroxisome Proliferator-activated Receptor-γ Activation. J Int Med Res 2008; 36:237-43. [DOI: 10.1177/147323000803600204] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
This study examined whether telmisartan, a unique angiotensin II type 1 receptor blocker (ARB) with peroxisome proliferator-activated receptor-γ (PPAR-γ)-modulating activity, improved insulin resistance in advanced glycation end-product (AGE)-exposed human hepatoma (Hep3B) cells. AGE increased phosphorylation of insulin receptor substrate-1 (IRS-1) at serine-307 residues in Hep3B cells. It also decreased tyrosine phosphorylation of IRS-1 and, subsequently, reduced the association of the p85 subunit of phosphatidylinositol 3-kinase with IRS-1 and glycogen synthesis in insulin-exposed Hep3B cells, all of which were inhibited by telmisartan. The insulin-sensitizing properties of telmisartan in AGE-exposed Hep3B cells were significantly blocked by GW9662, an inhibitor of PPAR-γ. Candesartan, another ARB, did not affect AGEs-induced serine phosphorylation of IRS-1 at serine-307 residues in Hep3B cells. Our study suggests that telmisartan could improve AGE-elicited insulin resistance in Hep3B cells by inhibiting serine phosphorylation of IRS-1, at least in part, via activation of PPAR-γ. Telmisartan may play a protective role against hepatic insulin resistance in diabetes.
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Affiliation(s)
- T Yoshida
- Department of Medicine, Kurume University School of Medicine, Kurume, Japan
| | - S Yamagishi
- Department of Medicine, Kurume University School of Medicine, Kurume, Japan
| | - T Matsui
- Department of Medicine, Kurume University School of Medicine, Kurume, Japan
| | - K Nakamura
- Department of Medicine, Kurume University School of Medicine, Kurume, Japan
| | - T Ueno
- Department of Medicine, Kurume University School of Medicine, Kurume, Japan
| | - M Takeuchi
- Department of Pathophysiological Science, Faculty of Pharmaceutical Science, Hokuriku University, Kanazawa, Japan
| | - M Sata
- Department of Medicine, Kurume University School of Medicine, Kurume, Japan
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Yoshida Y, Yamagishi S, Ueda S, Yoshimura K, Okuda S, Yamakawa R. Aqueous humour levels of asymmetric dimethylarginine (ADMA) are correlated with pigment epithelium-derived factor (PEDF) in patients with uveitis. J Int Med Res 2008; 35:892-5. [PMID: 18084848 DOI: 10.1177/147323000703500618] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The association between the aqueous humour levels of asymmetric dimethylarginine (ADMA) and pigment epithelium-derived factor (PEDF) was evaluated. Aqueous humour levels of ADMA and PEDF were measured by high-performance liquid chromatography and enzyme-linked immunosorbent assay, respectively, in 31 uveitis samples and nine cataract control samples. Aqueous humour ADMA and PEDF levels were significantly higher in infectious and non-infectious uveitis patients than in controls (0.67+/-0.04 nmol/ml and 0.55+/-0.03 nmol/ml versus 0.43+/-0.04 nmol/ml for ADMA; 8.22+/-1.45 microg/ml and 5.22+/-0.95 microg/ml versus 1.32+/-0.22 microg/ml for PEDF). A significant positive correlation between ADMA and PEDF levels in aqueous humour was found in control and uveitis patients. These results demonstrated that the aqueous humour level of ADMA is correlated with PEDF in humans and suggest that both ADMA and PEDF in aqueous humour may be elevated in response to inflammation in uveitis.
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Affiliation(s)
- Y Yoshida
- Department of Ophthalmology, Kurume University School of Medicine, Japan
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Matsui T, Yamagishi S, Nakamura K, Inoue H. Bay w 9798, a dihydropyridine structurally related to nifedipine with no calcium channel-blocking properties, inhibits tumour necrosis factor-alpha-induced vascular cell adhesion molecule-1 expression in endothelial cells by suppressing reactive oxygen species generation. J Int Med Res 2008; 35:886-91. [PMID: 18084847 DOI: 10.1177/147323000703500617] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Dihydropyridine-based calcium antagonists (DHPs) are widely used to treat hypertension. We have previously shown that nifedipine, one of the most popular DHPs, blocks tumour necrosis factor-alpha (TNF-alpha)-induced monocyte chemoattractant protein-1 as well as vascular cell adhesion molecule-1 (VCAM-1) expression in endothelial cells by suppressing reactive oxygen species generation (ROS). The molecular mechanism is still to be elucidated, however, because endothelial cells do not possess voltage-operated L-type calcium channels. The aim of this study was to determine in TNF-alpha-exposed human umbilical vein endothelial cells (HUVECs) whether and how Bay w 9798, a dihydropyridine structurally related to nifedipine with no calcium antagonistic properties, may suppress VCAM-1 expression, a key molecule which mediates the adhesion of monocytes to vasculature in the early stages of atherosclerosis. In HUVECs, 10 ng/ml TNF-alpha for 4 h stimulated ROS generation and subsequently upregulated VCAM-1 mRNA levels, both of which were dose-dependently blocked by Bay w 9798. The results demonstrated that Bay w 9798 inhibited VCAM-1 expression in TNF-alpha-exposed cells by suppressing ROS generation. They suggest that the anti-inflammatory and anti-oxidative properties of nifedipine and Bay w 9798 may be ascribed to the dihydropyridine structure, which is common to both molecules and has no calcium antagonistic ability.
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Affiliation(s)
- T Matsui
- Department of Medicine, Institute for Basic and Clinical Medicine, Kurume University School of Medicine, Japan
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Kajioka T, Miura K, Kitahara Y, Yamagishi S. Potential utility of combination therapy with nateglinide and telmisartan for metabolic derangements in Zucker Fatty rats. Horm Metab Res 2007; 39:889-93. [PMID: 17987547 DOI: 10.1055/s-2007-992798] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
The metabolic syndrome is strongly associated with insulin resistance and has been recognized as a cluster of risk factors for cardiovascular disease. Insulin resistance and/or impaired early-phase insulin secretion are major determinants of postprandial hyperglycemia. In this study, we investigated the potential utility of combination therapy with telmisartan, an angiotensin II receptor blocker and nateglinide, a rapid-onset/short-duration insulinotropic agent, for the treatment of postprandial hyperglycemia and metabolic derangements in Zucker Fatty (ZF) rats. ZF rats fed twice daily were given vehicle, 50 mg/kg of nateglinide, 5 mg/kg of telmisartan, or both for 6 weeks. Combination therapy with nateglinide and telmisartan for 2 weeks ameliorated postprandial hyperglycemia in ZF rats fed twice daily. Furthermore, 6-week treatment with nateglinide and telmisartan not only decreased fasting plasma insulin, triglycerides, and free fatty acid levels, but also improved the responses of blood glucose to insulin and subsequently reduced the decremental glucose areas under the curve in the ZF rats. Combination therapy also restored the decrease of plasma adiponectin levels in the ZF rats. Monotherapy with nateglinide or telmisartan alone didnot significantly improve these metabolic parameters. These observations demonstrate that combination therapy with nateglinide and telmisartan may improve the metabolic derangements by ameliorating early phase of insulin secretion as well as insulin resistance in ZF rats fed twice daily. Our present findings suggest that the combination therapy with nateglinide and telmisartan could be a promising therapeutic strategy for the treatment of the metabolic syndrome.
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Affiliation(s)
- T Kajioka
- Pharmaceutical Research Laboratories, Ajinomoto, Kawasaki, Japan
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Yamagishi S, Adachi H, Takeuchi M, Enomoto M, Furuki K, Matsui T, Nakamura K, Imaizumi T. Serum level of advanced glycation end-products (AGEs) is an independent determinant of plasminogen activator inhibitor-1 (PAI-1) in nondiabetic general population. Horm Metab Res 2007; 39:845-8. [PMID: 17992643 DOI: 10.1055/s-2007-991176] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Glucose can react nonenzymatically with amino groups of proteins to form senescent macroprotein derivatives termed advanced glycation end-products (AGEs). Recently, AGEs have been shown to play an important role in atherosclerosis even in nondiabetic subjects. However, the molecular mechanism underlying this is not fully understood. We have now investigated whether serum AGE level was an independent determinant of plasminogen activator inhibitor-1 (PAI-1), a major physiological inhibitor of fibrinolysis, in nondiabetic general population. One-hundred and eighty-six nondiabetic Japanese subjects underwent a complete history and physical examination, determination of blood chemistries, PAI-1, and AGEs. Uni- and multivariate analyses were applied for the determinants of PAI-1 levels. The average PAI-1 levels were 29.7+/-23.8 ng/ml in males and 21.8+/-17.1 ng/ml in females, respectively. Univariate regression analysis showed that PAI-1 levels were associated with age (inversely, p=0.003), male (p=0.003), body mass index (BMI) (p<0.001), HDL-cholesterol (inversely, p<0.001), triglycerides (p<0.001), fasting plasma glucose (p<0.001), insulin (p<0.001), uric acids (p<0.001), AGEs (p=0.037), and alcohol intake (p<0.001). By the use of multiple regression analyses, BMI (p<0.001), male (p=0.003), fasting plasma glucose (p=0.005), age (inversely, p=0.017), and AGEs (p=0.034) remained significant. The present study is the first demonstration that serum AGE level was one of the independent determinants of PAI-1 in nondiabetic general population. The AGE-associated thrombogenic abnormality may be involved in atherogenesis in nondiabetic subjects.
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Affiliation(s)
- S Yamagishi
- Department of Medicine, Division of Cardiovascular Medicine, Kurume University School of Medicine, Kurume, Japan.
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Yamagishi S, Abe R, Jinnouchi Y, Matsui T, Imaizumi T, Inoue H. Pigment Epithelium-derived Factor Inhibits Vascular Endothelial Growth Factor-induced Vascular Hyperpermeability Both In Vitro and In Vivo. J Int Med Res 2007; 35:896-899. [DOI: 10.1177/147323000703500619] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/30/2023] Open
Abstract
Administration of pigment epithelium-derived factor (PEDF) inhibits advanced glycation end products-elicited retinal vascular hyperpermeability, as well as cold injury-induced brain oedema in rats. However, the underlying molecular mechanism by which PEDF blocks the hyperpermeability in vivo is not fully understood. This study investigated whether PEDF could inhibit vascular endothelial growth factor (VEGF)-induced vascular hyperpermeability both in vitro and in vivo. The Miles assay revealed that, after intradermal injection of VEGF in nude mice, simultaneous administration of PEDF inhibited vascular hyperpermeability in a dose-dependent manner. The in vitro permeability assay also showed that PEDF blocked the VEGF-induced barrier dysfunction in endothelial cells. These results demonstrated that PEDF could inhibit the VEGF-induced vascular hyperpermeability both in vitro and in vivo, and suggest that PEGF may be suitable to be considered as a novel therapeutic agent for various vasopermeable disorders in which VEGF is involved.
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Affiliation(s)
- S Yamagishi
- Department of Medicine, Kurume University School of Medicine, Kurume, Japan
| | - R Abe
- Department of Dermatology, Hokkaido University School of Medicine, Sapporo, Japan
| | - Y Jinnouchi
- Department of Medicine, Kurume University School of Medicine, Kurume, Japan
| | - T Matsui
- Department of Medicine, Kurume University School of Medicine, Kurume, Japan
| | - T Imaizumi
- Department of Medicine, Kurume University School of Medicine, Kurume, Japan
| | - H Inoue
- Radioisotope Institute for Basic and Clinical Medicine, Kurume University School of Medicine, Kurume, Japan
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Matsui T, Yamagishi S, Ueda S, Nakamura K, Imaizumi T, Takeuchi M, Inoue H. Telmisartan, an angiotensin II type 1 receptor blocker, inhibits advanced glycation end-product (AGE)-induced monocyte chemoattractant protein-1 expression in mesangial cells through downregulation of receptor for AGEs via peroxisome proliferator-activated receptor-gamma activation. J Int Med Res 2007; 35:482-9. [PMID: 17697525 DOI: 10.1177/147323000703500407] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Interaction between advanced glycation end-products (AGEs) and their receptor (RAGE) plays a central role in diabetic nephropathy pathogenesis. Pathophysiological crosstalk between the AGEs-RAGE system and angiotensin II (Ang II) is also involved in this disease. This study investigated the role of proliferator-activated receptor-gamma (PPAR-gamma)-modulating activity on inhibition of monocyte chemoattractant protein (MCP-1) expression. Telmisartan, an Ang II type 1 receptor blocker, downregulated RAGE mRNA and inhibited superoxide generation and MCP-1 gene expression in mesangial cells; these processes were blocked by GW9662, a PPAR-gamma inhibitor. Candesartan, an Ang II type 1 receptor blocker, did not suppress AGEs-induced superoxide generation. Telmisartan and the antioxidant, N-acetylcysteine, completely inhibited AGEs-induced MCP-1 overproduction by mesangial cells. These results suggest that telmisartan inhibits AGEs-signalling to MCP-1 expression in mesangial cells by downregulating RAGE gene expression and subsequent oxidative stress generation via PPAR-gamma activation. This study has demonstrated a unique benefit of telmisartan in that it may function as an anti-inflammatory agent against AGEs via PPAR-gamma activation and may play a protective role in diabetic nephropathy.
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Affiliation(s)
- T Matsui
- Department of Medicine, Institute for Basic and Clinical Medicine, Kurume University School of Medicine, Kurume, Japan
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Takizawa R, Pawankar R, Yamagishi S, Takenaka H, Yagi T. Increased expression of HLA-DR and CD86 in nasal epithelial cells in allergic rhinitics: antigen presentation to T cells and up-regulation by diesel exhaust particles. Clin Exp Allergy 2007; 37:420-33. [PMID: 17359392 PMCID: PMC7164828 DOI: 10.1111/j.1365-2222.2007.02672.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
BACKGROUND A proportion of nasal epithelial cells (NEC) in patients with allergic rhinitis (AR) are known to express the major histocompatibility complex Class II molecule (HLA-DR). OBJECTIVE We hypothesized that NEC may play a role in antigen presentation to T cells. To elucidate the possible role of NEC in antigen presentation, we examined the expression of HLA-DR, CD80 and CD86 in NEC, their regulation by cytokines and the capacity of NEC to induce antigen-specific proliferation of T cells. METHODS We examined the expression of HLA-DR, CD80 and CD86 in nasal epithelial scrapings of patients with seasonal allergic rhinitis (SAR) to Japanese cedar pollen pre-season and in-season, by immunohistochemistry. Next, we examined the effect of IL-1beta, TNF-alpha, (IFN-gamma), IL-4 alpha, IL-13 and diesel exhaust particles (DEP) on the HLA-DR, CD80 and CD86 expression in cultured nasal epithelial cells (CNEC), by flow cytometry. Further, we analysed the capacity of mite antigen (Der f II)-pulsed mitomycin-C-treated CNEC to induce proliferation of autologous T cells from patients with perennial allergic rhinitis. RESULTS NEC constitutively expressed HLA-DR and CD86, but not CD80. The expression of HLA-DR and CD86 in NEC was significantly increased in-season, in patients with SAR as compared with that of pre-season. While IFN-gamma up-regulated the expression of HLA-DR, IL-1beta and TNF-alpha up-regulated the expression of CD86 in CNEC. Furthermore, in the presence of mite antigen, CNEC induced the proliferation of autologous peripheral blood T lymphocytes. Anti-CD86 and anti-HLA-DR monoclonal antibody but not anti-CD80 inhibited the epithelial cell-induced T cell proliferation. Stimulation with a combination of DEP and mite antigen significantly up-regulated HLA-DR and CD86 expression in CNEC. CONCLUSIONS These studies suggest that NEC in patients with AR may play a role in antigen presentation through the enhanced expression of HLA-DR and CD86. Furthermore, these results suggest the possibility that DEP may enhance the antigen-presenting function of CNEC.
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Affiliation(s)
- R Takizawa
- Department of Otolaryngology, Nippon Medical School, Tokyo, Japan
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Nakamura K, Yamagishi S, Yoshida T, Matsui T, Imaizumi T, Inoue H, Sata M. Hydrogen peroxide stimulates pigment epithelium-derived factor gene and protein expression in the human hepatocyte cell line OUMS-29. J Int Med Res 2007; 35:427-32. [PMID: 17593873 DOI: 10.1177/147323000703500319] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Pigment epithelium-derived factor (PEDF) may have a protective role in atherosclerosis and is associated with the presence of components of the metabolic syndrome. Since oxidative stress has been postulated to play an important role in the pathogenesis of vascular injury in the metabolic syndrome, this study investigated the effects of hydrogen peroxide (H2O2) on PEDF in the immortalized human hepatocyte cell line OUMS-29. PEDF gene expression was measured using quantitative real-time reverse transcription-polymerase chain reaction and PEDF protein expression was analysed by Western blot. H2O2 upregulated PEDF mRNA levels and increased PEDF protein production in OUMS-29 cells in time- and dose-dependent manners. The anti-oxidant N-acetylcysteine significantly blocked H2O2-induced PEDF overexpression in OUMS-29 cells. These results suggest that hepatic PEDF levels may be elevated to counteract the effects of oxidative stress. H2O2-induced PEDF overproduction in the liver may act as a negative feedback system against vascular damage in the metabolic syndrome.
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Affiliation(s)
- K Nakamura
- Department of Internal Medicine, Kurume University School of Medicine, Kurume, Japan
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Yoshida Y, Yamagishi S, Ueda S, Yoshimura K, Okuda S, Yamakawa R. Aqueous humor levels of asymmetric dimethylarginine (ADMA) are positively associated with monocyte chemoattractant protein-1 (MCP-1) in patients with uveitis. Br J Ophthalmol 2007; 92:93-4. [PMID: 17591667 DOI: 10.1136/bjo.2007.124966] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
BACKGROUND/AIMS The aim of the study was to evaluate whether aqueous humor levels of asymmetric dimethylarginine (ADMA) are associated with monocyte chemoattractant protein-1 (MCP-1). METHODS Aqueous humor levels of ADMA and MCP-1 were measured by high-performance liquid chromatography (HPLC) and ELISA, respectively, in 31 uveitis samples and nine cataract control samples. RESULTS Aqueous humor ADMA and MCP-1 levels were significantly higher in infectious or non-infectious uveitis patients than in controls (0.67+/-0.04 nmol/ml vs 0.55+/-0.03 nmol/ml vs 0.43+/-0. 04 nmol/ml (p<0.01) and 29.0+/-11.3 ng/ml vs 4.5+/-1.2 ng/ml vs 0.47+/-0.1 ng/ml (p<0.01), respectively). A positive correlation between ADMA and MCP-1 levels in aqueous humor was found in control and uveitis patients (r = 0.33, p<0.05). CONCLUSION The results demonstrated that aqueous humor levels of ADMA were positively associated with MCP-1 in humans. Our present observations suggest that aqueous humor levels of ADMA may be a novel biomarker of inflammation in uveitis.
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Affiliation(s)
- Y Yoshida
- Department of Ophthalmology, Kurume University School of Medicine, Kurume 830-0011, Japan
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Abstract
Diabetic nephropathy is a leading cause of end-stage renal failure, which could account for disabilities and high mortality rates in patients with diabetes. Diabetic nephropathy seems to occur as a result of an interaction between metabolic and hemodynamic factors, which activate common pathways that lead to renal damage. Recent large prospective clinical studies have shown that intensive glucose control reduces microvascular complications effectively among patients with diabetes, and the renin-angiotensin system (RAS) is also an important target for both metabolic and hemodynamic derangements in diabetic nephropathy. High glucose, via various mechanisms such as increased production of oxidative stress and advanced glycation end products (AGEs), activation of the RAS and protein kinase C (PKC), and stimulation of the polyol pathway, elicits vascular inflammation and alters gene expression of growth factors and cytokines, thereby it might be involved in the development and progression of diabetic nephropathy. Therefore, to develop novel therapeutic strategies that specifically target these metabolic and hemodynamic derangements is desired for patients with diabetic nephropathy. In this review, we discuss the molecular mechanisms of diabetic nephropathy and review the promising therapeutic targets for this devastating disorder.
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Affiliation(s)
- K Fukami
- Division of Nephrology, Department of Medicine, Kurume University School of Medicine, 67 Asahi-machi, Kurume 830-0011, Japan.
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Matsui T, Yamagishi S, Nakamura K, Inoue H. Azelnidipine, a new long-acting calcium-channel blocker, inhibits tumour necrosis factor-alpha-induced monocyte chemoattractant protein-1 expression in endothelial cells. J Int Med Res 2007; 34:671-5. [PMID: 17295000 DOI: 10.1177/147323000603400613] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Dihydropyridine-based calcium antagonists are among the most widely used drugs for the treatment of hypertension. Since azelnidipine is a highly lipid-soluble dihydropyridine-based calcium antagonist with high vascular affinity, it is conceivable that azelnidipine could play a protective role against atherosclerosis. The aim of this study was to determine whether azelnidipine could suppress the expression of monocyte chemoattractant protein-1, a principal chemokine which mediates the recruitment of monocytes to the vasculature, in tumour necrosis factor (TNF)-alpha-exposed human umbilical vein endothelial cells. TNF-alpha, at a concentration of 10 ng/ml, upregulated monocyte chemoattractant protein-1 mRNA levels about seven-fold. Azelnidipine, 10 nmol/l, was found to inhibit the TNF-alpha-induced upregulation of monocyte chemoattractant protein-1 mRNA levels in human umbilical vein endothelial cells significantly. Furthermore, azelnidipine suppressed TNF-alpha-induced monocyte chemoattractant protein-1 production by human umbilical vein endothelial cells. This study demonstrates a novel beneficial aspect of azelnidipine, whereby azelnidipine could play a protective role against atherosclerosis by suppressing monocyte chemoattractant protein-1 overexpression in endothelial cells.
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Affiliation(s)
- T Matsui
- Department of Internal Medicine, Institute for Basic and Clinical Medicine, Kurume University School of Medicine, Kurume, Japan
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Yamagishi S, Nakamura K, Matsui T, Inoue H, Takeuchi M. Oral administration of AST-120 (Kremezin) is a promising therapeutic strategy for advanced glycation end product (AGE)-related disorders. Med Hypotheses 2007; 69:666-8. [PMID: 17331665 DOI: 10.1016/j.mehy.2006.12.045] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2006] [Accepted: 12/07/2006] [Indexed: 01/12/2023]
Abstract
The pathological role of the non-enzymatic modification of proteins by reducing sugars has become increasingly evident in various disorders. It is now well established that early glycation products undergo progressive modification over time in vivo to the formation of irreversible cross-links, after which these molecules are termed "AGEs (advanced glycation end products)". AGEs have been implicated in the development of many of the pathological sequelae of diabetes and aging, such as diabetic microangiopathy, ischemic heart disease and neurodegenerative diseases. Recently, digested food-derived AGEs are also found to play an important role in the pathogenesis of AGE-related disorders. Diet is a major environmental source of pro-inflammatory AGEs. Indeed, restriction of dietary glycotoxins decreases excessive AGE levels and subsequently reduces the inflammatory responses in patients with diabetes. These observations suggest that inhibition of absorption of dietary AGEs may be a novel target for therapeutic intervention in the above-mentioned AGE-related disorders. AST-120 (Kremezin) is an oral adsorbent that attenuates the progression of chronic renal failure (CRF) by removing uremic toxins. We have recently found that AST-120 binds to carboxymethyllysine (CML), one of the well-characterized, digested food-derived AGEs in vitro and that administration of AST-120 decreases serum levels of AGEs in non-diabetic CRF patients. These findings suggest that digested food-derived AGEs such as CML may be a novel molecular target for oral adsorbent AST-120 and that AST-120 could exert beneficial effects on CRF patients by adsorbing diet-derived AGEs and subsequently decreasing serum AGE levels. If our speculation is correct, AST-120 may have therapeutic potentials for the treatment of patients with various AGE-related disorders as well. In this paper, we would like to propose the possible ways of testing our hypotheses. Does the long-term treatment of AST-120 decrease serum and tissue levels of AGEs in diabetic patients? Does this treatment also reduce the risk for the development and progression of diabetic vascular complications such as diabetic retinopathy or ischemic heart disease? If the answers are yes, do the serum and/or tissue levels of AGEs after AST-120 treatment predict its beneficial effects on diabetic vascular complications? How about the effects of AST-120 on Alzheimer's disease, another AGE-related neurodegenerative disorder? Does the treatment of AST-120 reduce the risk for Alzheimer's disease and/or improve the cognitive impairment of patients with this disorder? These prospective studies will provide further valuable information whether the inhibition of absorption of dietary AGEs by AST-120 could be clinically relevant.
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Affiliation(s)
- S Yamagishi
- Department of Medicine, Kurume University School of Medicine, 67 Asahi-machi, Kurume 830-0011, Japan.
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Jinnouchi Y, Yamagishi S, Takeuchi M, Ishida S, Jinnouchi Y, Jinnouchi J, Imaizumi T. Atorvastatin decreases serum levels of advanced glycation end products (AGEs) in patients with type 2 diabetes. Clin Exp Med 2007; 6:191-3. [PMID: 17191111 DOI: 10.1007/s10238-006-0115-6] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2006] [Accepted: 10/10/2006] [Indexed: 10/23/2022]
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Abstract
A recent analysis by the Blood Pressure Lowering Treatment Trialists' Collaboration revealed that any commonly-used blood pressure (BP)-lowering regimen reduced the risk of total major cardiovascular events, and larger reductions in BP produced larger reductions in the risk. These observations suggest that most of the differences among treatment regimens in their effects on cardiovascular outcomes could be explained by the differences in achieved BP level. However, it may also be true that some treatment regimen is superior or inferior to others with regard to the risk reduction of cardiovascular events. Indeed, the data from dihydropyridine-based calcium antagonist (DHP) trails are consistent in that they could not protect against new-onset heart failure or progression of renal disease in patients with left-ventricular systolic dysfunction or overt proteinuria, respectively. However, a multicenter, randomized, placebo-controlled, double-blind ACTION trial, which compared the effect of long-acting nifedipine or placebo on mortality and cardiovascular morbidity in patients with stable angina, revealed that nifedipine reduced the risk for new-onset overt heart failure by 29%. Further, an open-label, randomized prospective J-MIND trial, which compared the effect of long-acting nifedipine or enalapril, an angiotensin-converting enzyme inhibitor on onset and progression of nephropathy in hypertensive patients with type 2 diabetes, showed that long-acting nifedipine had an equipotent reoprotective effect on diabetic nephropathy. In this paper, we would like to propose our hypothesis that nifedipine may be unique and superior in its effects on heart failure and proteinuria compared with various DHPs. For ensuring our hypothesis, the following clinical issues would be addressed. Does nifedipine treatment alone decrease the progression of renal disease with overt proteinuria? If these answers are yes, are these beneficial effects of nifedipine superior to that of other DHPs with equihypotensive properties? Does nifedipine treatment also reduce oxidative stress markers? Are these unique effects of nifedipine correlated with its anti-oxidative properties? These prospective studies will provide further valuable information whether nifedipine may be a preferred DHP to achieve BP goals in hypertensive patients with systolic dysfunction or overt proteinuria.
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Affiliation(s)
- S Yamagishi
- Department of Internal Medicine, Kurume University School of Medicine, 67 Asahi-machi, Kurume 830-0011, Japan.
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