published_papers "タイトル(日本語)","タイトル(英語)","著者(日本語)","著者(英語)","担当区分","概要(日本語)","概要(英語)","出版者・発行元(日本語)","出版者・発行元(英語)","出版年月","誌名(日本語)","誌名(英語)","巻","号","開始ページ","終了ページ","記述言語","査読の有無","招待の有無","掲載種別","国際・国内誌","国際共著","DOI","ISSN","eISSN","URL","URL2","主要な業績かどうか","公開の有無" "25-hydroxyvitamin D-1α-hydroxylase (CYP27B1) induces ectopic calcification.","25-hydroxyvitamin D-1α-hydroxylase (CYP27B1) induces ectopic calcification.","Yilimulati Yimamu, Ayako Ohtani, Yuichiro Takei, Airi Furuichi, Yuki Kamei, Hisami Okumura, Hirokazu Ohminami, Masashi Masuda, Makoto Miyazaki, Hironori Yamamoto, Yutaka Taketani","Yilimulati Yimamu, Ayako Ohtani, Yuichiro Takei, Airi Furuichi, Yuki Kamei, Hisami Okumura, Hirokazu Ohminami, Masashi Masuda, Makoto Miyazaki, Hironori Yamamoto, Yutaka Taketani","null","Vascular calcification is an important pathogenesis related to cardiovascular disease and high mortality rate in chronic kidney disease (CKD) patients. It has been well-known that hyper-phosphatemia induces osteochondrogenic transition of vascular smooth muscle cells (VSMCs) resulting ectopic calcification in aortic media, cardiac valve, and kidney. However, the detailed mechanism of the ectopic calcification has been not clarified yet. Here, we found that the co-localization of CYP27B1 with the calcified lesions of aorta and arteries in kidney of klotho mutant () mice, and then investigated the role of CYP27B1 in the mineralization of the VSMCs. Under high phosphate condition, overexpression of CYP27B1 induced calcification and osteocalcin mRNA expression in the VSMCs. Inversely, siRNA- inhibited high phosphate-induced calcification of the VSMCs. We also found that the accumulated CYP27B1 protein was glycosylated in the kidney of mice. Therefore, overexpression of CYP27B1-N310A and CYP27B1-T439A, which are a mutation for -linked glycosylation site (N310A) and a mutation for -linked glycosylation site (T439A) in CYP27B1, decreased calcium deposition and expression of RUNX2 induced by high phosphate medium in VSMCs compared with wild-type CYP27B1. These results suggest that extra-renal expression of glycosylated CYP27B1 would be required for ectopic calcification of VSMCs under hyperphosphatemia.","Vascular calcification is an important pathogenesis related to cardiovascular disease and high mortality rate in chronic kidney disease (CKD) patients. It has been well-known that hyper-phosphatemia induces osteochondrogenic transition of vascular smooth muscle cells (VSMCs) resulting ectopic calcification in aortic media, cardiac valve, and kidney. However, the detailed mechanism of the ectopic calcification has been not clarified yet. Here, we found that the co-localization of CYP27B1 with the calcified lesions of aorta and arteries in kidney of klotho mutant () mice, and then investigated the role of CYP27B1 in the mineralization of the VSMCs. Under high phosphate condition, overexpression of CYP27B1 induced calcification and osteocalcin mRNA expression in the VSMCs. Inversely, siRNA- inhibited high phosphate-induced calcification of the VSMCs. We also found that the accumulated CYP27B1 protein was glycosylated in the kidney of mice. Therefore, overexpression of CYP27B1-N310A and CYP27B1-T439A, which are a mutation for -linked glycosylation site (N310A) and a mutation for -linked glycosylation site (T439A) in CYP27B1, decreased calcium deposition and expression of RUNX2 induced by high phosphate medium in VSMCs compared with wild-type CYP27B1. These results suggest that extra-renal expression of glycosylated CYP27B1 would be required for ectopic calcification of VSMCs under hyperphosphatemia.","null","null","2022-06-04","Journal of Clinical Biochemistry and Nutrition","Journal of Clinical Biochemistry and Nutrition","Vol.71","No.2","103","111","eng","true","null","scientific_journal","null","null","10.3164/jcbn.22-16","0912-0009","null","null","null","null","null" "Sulforaphane induces lipophagy through the activation of AMPK-mTOR-ULK1 pathway signaling in adipocytes.","Sulforaphane induces lipophagy through the activation of AMPK-mTOR-ULK1 pathway signaling in adipocytes.","Masashi Masuda, Risa Yoshida-Shimizu, Yuki Mori, Kohta Ohnishi, Yuichiro Adachi, Maiko Sakai, Serina Kabutoya, Hirokazu Ohminami, Hirokazu Ohminami, Hironori Yamamoto, Makoto Miyazaki, Yutaka Taketani","Masashi Masuda, Risa Yoshida-Shimizu, Yuki Mori, Kohta Ohnishi, Yuichiro Adachi, Maiko Sakai, Serina Kabutoya, Hirokazu Ohminami, Hirokazu Ohminami, Hironori Yamamoto, Makoto Miyazaki, Yutaka Taketani","null","Lipophagy, a form of selective autophagy, degrades lipid droplet (LD) in adipose tissue and the liver. The chemotherapeutic isothiocyanate sulforaphane (SFN) contributes to lipolysis through the activation of hormone-sensitive lipase and the browning of white adipocytes. However, the details concerning the regulation of lipolysis in adipocytes by SFN-mediated autophagy remain unclear. In this study, we investigated the effects of SFN on autophagy in the epididymal fat of mice fed a high-fat diet (HFD) or control-fat diet and on the molecular mechanisms of autophagy in differentiated 3T3-L1 cells. Western blotting revealed that the protein expression of lipidated LC3 (LC3-II), an autophagic substrate, was induced after 3T3-L1 adipocytes treatment with SFN. In addition, SFN increased the LC3-II protein expression in the epididymal fat of mice fed an HFD. Immunofluorescence showed that the SFN-induced LC3 expression was co-localized with LDs in 3T3-L1 adipocytes and with perilipin, the most abundant adipocyte-specific protein, in adipocytes of mice fed an HFD. Next, we confirmed that SFN activates autophagy flux in differentiated 3T3-L1 cells using the mCherry-EGFP-LC3 and GFP-LC3-RFP-LC3 probe. Furthermore, we examined the induction mechanisms of autophagy by SFN in 3T3-L1 adipocytes using western blotting. ATG5 knockdown partially blocked the SFN-induced release of fatty acids from LDs in mature 3T3-L1 adipocytes. SFN time-dependently elicited the phosphorylation of AMPK, the dephosphorylation of mTOR, and the phosphorylation of ULK1 in differentiated 3T3-L1 cells. Taken together, these results suggest that SFN may provoke lipophagy through AMPK-mTOR-ULK1 pathway signaling, resulting in partial lipolysis of adipocytes.","Lipophagy, a form of selective autophagy, degrades lipid droplet (LD) in adipose tissue and the liver. The chemotherapeutic isothiocyanate sulforaphane (SFN) contributes to lipolysis through the activation of hormone-sensitive lipase and the browning of white adipocytes. However, the details concerning the regulation of lipolysis in adipocytes by SFN-mediated autophagy remain unclear. In this study, we investigated the effects of SFN on autophagy in the epididymal fat of mice fed a high-fat diet (HFD) or control-fat diet and on the molecular mechanisms of autophagy in differentiated 3T3-L1 cells. Western blotting revealed that the protein expression of lipidated LC3 (LC3-II), an autophagic substrate, was induced after 3T3-L1 adipocytes treatment with SFN. In addition, SFN increased the LC3-II protein expression in the epididymal fat of mice fed an HFD. Immunofluorescence showed that the SFN-induced LC3 expression was co-localized with LDs in 3T3-L1 adipocytes and with perilipin, the most abundant adipocyte-specific protein, in adipocytes of mice fed an HFD. Next, we confirmed that SFN activates autophagy flux in differentiated 3T3-L1 cells using the mCherry-EGFP-LC3 and GFP-LC3-RFP-LC3 probe. Furthermore, we examined the induction mechanisms of autophagy by SFN in 3T3-L1 adipocytes using western blotting. ATG5 knockdown partially blocked the SFN-induced release of fatty acids from LDs in mature 3T3-L1 adipocytes. SFN time-dependently elicited the phosphorylation of AMPK, the dephosphorylation of mTOR, and the phosphorylation of ULK1 in differentiated 3T3-L1 cells. Taken together, these results suggest that SFN may provoke lipophagy through AMPK-mTOR-ULK1 pathway signaling, resulting in partial lipolysis of adipocytes.","null","null","2022-04-21","The Journal of Nutritional Biochemistry","The Journal of Nutritional Biochemistry","Vol.106","null","109017","109017","eng","true","null","scientific_journal","null","null","10.1016/j.jnutbio.2022.109017","1873-4847","null","null","null","null","null" "All-trans retinoic acid changes muscle fiber type via increasing GADD34 dependent on MAPK signal.","All-trans retinoic acid changes muscle fiber type via increasing GADD34 dependent on MAPK signal.","Yuichiro Adachi, Masashi Masuda, Iori Sakakibara, Takayuki Uchida, Yuki Niida, Yuki Mori, Yuki Kamei, Yosuke Okumura, Hirokazu Ohminami, Kohta Ohnishi, Hisami Okumura, Takeshi Nikawa, Yutaka Taketani","Yuichiro Adachi, Masashi Masuda, Iori Sakakibara, Takayuki Uchida, Yuki Niida, Yuki Mori, Yuki Kamei, Yosuke Okumura, Hirokazu Ohminami, Kohta Ohnishi, Hisami Okumura, Takeshi Nikawa, Yutaka Taketani","null","All-trans retinoic acid (ATRA) increases the sensitivity to unfolded protein response in differentiating leukemic blasts. The downstream transcriptional factor of PERK, a major arm of unfolded protein response, regulates muscle differentiation. However, the role of growth arrest and DNA damage-inducible protein 34 (GADD34), one of the downstream factors of PERK, and the effects of ATRA on GADD34 expression in muscle remain unclear. In this study, we identified ATRA increased the GADD34 expression independent of the PERK signal in the gastrocnemius muscle of mice. ATRA up-regulated GADD34 expression through the transcriptional activation of gene via inhibiting the interaction of homeobox Six1 and transcription co-repressor TLE3 with the MEF3-binding site on the gene promoter in skeletal muscle. ATRA also inhibited the interaction of TTP, which induces mRNA degradation, with AU-rich element on mRNA via p-38 MAPK, resulting in the instability of mRNA. Overexpressed GADD34 in C2C12 cells changes the type of myosin heavy chain in myotubes. These results suggest ATRA increases GADD34 expression via transcriptional and post-transcriptional regulation, which changes muscle fiber type.","All-trans retinoic acid (ATRA) increases the sensitivity to unfolded protein response in differentiating leukemic blasts. The downstream transcriptional factor of PERK, a major arm of unfolded protein response, regulates muscle differentiation. However, the role of growth arrest and DNA damage-inducible protein 34 (GADD34), one of the downstream factors of PERK, and the effects of ATRA on GADD34 expression in muscle remain unclear. In this study, we identified ATRA increased the GADD34 expression independent of the PERK signal in the gastrocnemius muscle of mice. ATRA up-regulated GADD34 expression through the transcriptional activation of gene via inhibiting the interaction of homeobox Six1 and transcription co-repressor TLE3 with the MEF3-binding site on the gene promoter in skeletal muscle. ATRA also inhibited the interaction of TTP, which induces mRNA degradation, with AU-rich element on mRNA via p-38 MAPK, resulting in the instability of mRNA. Overexpressed GADD34 in C2C12 cells changes the type of myosin heavy chain in myotubes. These results suggest ATRA increases GADD34 expression via transcriptional and post-transcriptional regulation, which changes muscle fiber type.","null","null","2022-03-22","Life Science Alliance","Life Science Alliance","Vol.5","No.7","null","null","eng","true","null","scientific_journal","null","null","10.26508/lsa.202101345","2575-1077","null","null","null","null","null" "Identification of Dietary Phytochemicals Capable of Enhancing the Autophagy Flux in HeLa and Caco-2 Human Cell Lines","Identification of Dietary Phytochemicals Capable of Enhancing the Autophagy Flux in HeLa and Caco-2 Human Cell Lines","Kohta Ohnishi, Yano Satoshi, Fujimoto Moe, Sakai Maiko, Harumoto Erika, Furuichi Airi, Masashi Masuda, Hirokazu Ohminami, Hisami Okumura, Hara Taichi, Yutaka Taketani","Kohta Ohnishi, Yano Satoshi, Fujimoto Moe, Sakai Maiko, Harumoto Erika, Furuichi Airi, Masashi Masuda, Hirokazu Ohminami, Hisami Okumura, Hara Taichi, Yutaka Taketani","null","null","null","null","null","2020-11-27","Antioxidants","Antioxidants","Vol.9","No.12","E1193","E1193","eng","true","null","scientific_journal","null","null","10.3390/antiox9121193","2076-3921","null","null","null","null","null" "All-trans retinoic acid reduces the transcriptional regulation of intestinal sodium-dependent phosphate co-transporter gene (Npt2b).","All-trans retinoic acid reduces the transcriptional regulation of intestinal sodium-dependent phosphate co-transporter gene (Npt2b).","Masashi Masuda, Hironori Yamamoto, Yuichiro Takei, Otoki Nakahashi, Yuichiroh Adachi, Kohta Ohnishi, Hirokazu Ohminami, Hisami Yamanaka-Okumura, Hiroshi Sakaue, Makoto Miyazaki, Eiji Takeda, Yutaka Taketani","Masashi Masuda, Hironori Yamamoto, Yuichiro Takei, Otoki Nakahashi, Yuichiroh Adachi, Kohta Ohnishi, Hirokazu Ohminami, Hisami Yamanaka-Okumura, Hiroshi Sakaue, Makoto Miyazaki, Eiji Takeda, Yutaka Taketani","null","Inorganic phosphate (Pi) homeostasis is regulated by intestinal absorption via type II sodium-dependent co-transporter (Npt2b) and by renal reabsorption via Npt2a and Npt2c. Although we previously reported that vitamin A-deficient (VAD) rats had increased urine Pi excretion through the decreased renal expression of Npt2a and Npt2c, the effect of vitamin A on the intestinal Npt2b expression remains unclear. In this study, we investigated the effects of treatment with all-trans retinoic acid (ATRA), a metabolite of vitamin A, on the Pi absorption and the Npt2b expression in the intestine of VAD rats, as well as and the underlying molecular mechanisms. In VAD rats, the intestinal Pi uptake activity and the expression of Npt2b were increased, but were reduced by the administration of ATRA. The transcriptional activity of reporter plasmid containing the promoter region of the rat Npt2b gene was reduced by ATRA in NIH3T3 cells overexpressing retinoic acid receptor (RAR) and retinoid X receptor (RXR). On the other hand, CCAAT/enhancer-binding proteins (C/EBP) induced transcriptional activity of the Npt2b gene. Knockdown of the C/EBP gene and a mutation analysis of the C/EBP responsible element in the Npt2b gene promoter indicated that C/EBP plays a pivotal role in the regulation of Npt2b gene transcriptional activity by ATRA. EMSA revealed that the RAR/RXR complex inhibits binding of C/EBP to Npt2b gene promoter. Together, these results suggest that ATRA may reduce the intestinal Pi uptake by preventing C/EBP activation of the intestinal Npt2b gene.","Inorganic phosphate (Pi) homeostasis is regulated by intestinal absorption via type II sodium-dependent co-transporter (Npt2b) and by renal reabsorption via Npt2a and Npt2c. Although we previously reported that vitamin A-deficient (VAD) rats had increased urine Pi excretion through the decreased renal expression of Npt2a and Npt2c, the effect of vitamin A on the intestinal Npt2b expression remains unclear. In this study, we investigated the effects of treatment with all-trans retinoic acid (ATRA), a metabolite of vitamin A, on the Pi absorption and the Npt2b expression in the intestine of VAD rats, as well as and the underlying molecular mechanisms. In VAD rats, the intestinal Pi uptake activity and the expression of Npt2b were increased, but were reduced by the administration of ATRA. The transcriptional activity of reporter plasmid containing the promoter region of the rat Npt2b gene was reduced by ATRA in NIH3T3 cells overexpressing retinoic acid receptor (RAR) and retinoid X receptor (RXR). On the other hand, CCAAT/enhancer-binding proteins (C/EBP) induced transcriptional activity of the Npt2b gene. Knockdown of the C/EBP gene and a mutation analysis of the C/EBP responsible element in the Npt2b gene promoter indicated that C/EBP plays a pivotal role in the regulation of Npt2b gene transcriptional activity by ATRA. EMSA revealed that the RAR/RXR complex inhibits binding of C/EBP to Npt2b gene promoter. Together, these results suggest that ATRA may reduce the intestinal Pi uptake by preventing C/EBP activation of the intestinal Npt2b gene.","null","null","2020-02-28","The Biochemical Journal","The Biochemical Journal","Vol.477","No.4","817","831","eng","true","null","scientific_journal","null","null","10.1042/BCJ20190716","1470-8728","null","null","null","null","null" "Isorhamnetin, a 3'-methoxylated flavonol, enhances the lysosomal proteolysis in J774.1 murine macrophages in a TFEB-independent manner.","Isorhamnetin, a 3'-methoxylated flavonol, enhances the lysosomal proteolysis in J774.1 murine macrophages in a TFEB-independent manner.","Maiko Sakai, Kohta Ohnishi, Masashi Masuda, Hirokazu Ohminami, Hisami Okumura, Taichi Hara, Yutaka Taketani","Maiko Sakai, Kohta Ohnishi, Masashi Masuda, Hirokazu Ohminami, Hisami Okumura, Taichi Hara, Yutaka Taketani","null","Lysosome is the principal organelle for the ultimate degradation of cellular macromolecules, which are delivered through endocytosis, phagocytosis, and autophagy. The lysosomal functions have been found to be impaired by fatty foods and aging, and more importantly, the lysosomal dysfunction in macrophages has been reported as a risk of atherosclerosis development. In this study, we searched for dietary polyphenols which possess the activity for enhancing the lysosomal degradation in J774.1, a murine macrophage-like cell line. Screening test utilizing DQ-BSA digestion identified isorhamnetin (3'--methylquercetin) as an active compound. Interestingly, structural comparison to inactive flavonols revealed that the chemical structure of the B-ring moiety in isorhamnetin is the primary determinant of its lysosome-enhancing activity. Unexpectedly isorhamnetin failed to inhibit mTORC1-TFEB signaling, a master regulator of lysosomal biogenesis and function. Our data suggested that the other molecular mechanism might be critical for the regulation of lysosomes in macrophages. ANOVA: analysis of variance; ApoE: apolipoprotein E; ATP6V0D2: ATPase H transporting V0 subunit d2; BAF: bafilomycin A1; BODIPY: boron dipyrromethene; BSA: bovine serum albumin; CTSD: cathepsin D; CTSF: cathepsin F; DMEM: Dulbecco's modified eagle medium; DMSO: dimethyl sulfoxide; EGCG: epigallocatechin-3-gallate; FBS: fetal bovine serum; GAPDH: glyceraldehyde-3-phosphate dehydrogenase; HPLC: high-performance liquid chromatography; LAMP1: lysosomal-associated membrane protein 1; LAMP2A: lysosomal-associated membrane protein 2A; LC-MS/MS: liquid chromatography tandem mass spectrometry; MITF: microphthalmia-associated transcription factor; MRM: multiple reaction monitoring; mTORC1: mechanistic target of rapamycin complex 1; PBS: phosphate-buffered saline; PPARγ: peroxisome proliferator-activated receptor γ; RT-qPCR: reverse transcription quantitative polymerase chain reaction; SDS: sodium dodecyl sulfate; SNARE: soluble N-ethylmaleimide-sensitive-factor attachment protein receptor; TBS: Tris-buffered saline; TFA: trifluoroacetic acid; TFE3: transcription factor binding to IGHM enhancer 3; TFEB: transcriptional factor EB; TFEC: transcription factor EC; V-ATPase: vacuolar-type proton ATPase.","Lysosome is the principal organelle for the ultimate degradation of cellular macromolecules, which are delivered through endocytosis, phagocytosis, and autophagy. The lysosomal functions have been found to be impaired by fatty foods and aging, and more importantly, the lysosomal dysfunction in macrophages has been reported as a risk of atherosclerosis development. In this study, we searched for dietary polyphenols which possess the activity for enhancing the lysosomal degradation in J774.1, a murine macrophage-like cell line. Screening test utilizing DQ-BSA digestion identified isorhamnetin (3'--methylquercetin) as an active compound. Interestingly, structural comparison to inactive flavonols revealed that the chemical structure of the B-ring moiety in isorhamnetin is the primary determinant of its lysosome-enhancing activity. Unexpectedly isorhamnetin failed to inhibit mTORC1-TFEB signaling, a master regulator of lysosomal biogenesis and function. Our data suggested that the other molecular mechanism might be critical for the regulation of lysosomes in macrophages. ANOVA: analysis of variance; ApoE: apolipoprotein E; ATP6V0D2: ATPase H transporting V0 subunit d2; BAF: bafilomycin A1; BODIPY: boron dipyrromethene; BSA: bovine serum albumin; CTSD: cathepsin D; CTSF: cathepsin F; DMEM: Dulbecco's modified eagle medium; DMSO: dimethyl sulfoxide; EGCG: epigallocatechin-3-gallate; FBS: fetal bovine serum; GAPDH: glyceraldehyde-3-phosphate dehydrogenase; HPLC: high-performance liquid chromatography; LAMP1: lysosomal-associated membrane protein 1; LAMP2A: lysosomal-associated membrane protein 2A; LC-MS/MS: liquid chromatography tandem mass spectrometry; MITF: microphthalmia-associated transcription factor; MRM: multiple reaction monitoring; mTORC1: mechanistic target of rapamycin complex 1; PBS: phosphate-buffered saline; PPARγ: peroxisome proliferator-activated receptor γ; RT-qPCR: reverse transcription quantitative polymerase chain reaction; SDS: sodium dodecyl sulfate; SNARE: soluble N-ethylmaleimide-sensitive-factor attachment protein receptor; TBS: Tris-buffered saline; TFA: trifluoroacetic acid; TFE3: transcription factor binding to IGHM enhancer 3; TFEB: transcriptional factor EB; TFEC: transcription factor EC; V-ATPase: vacuolar-type proton ATPase.","null","null","2020-02-12","Bioscience, Biotechnology, and Biochemistry","Bioscience, Biotechnology, and Biochemistry","null","null","null","null","eng","true","null","scientific_journal","null","null","10.1080/09168451.2020.1727309","1347-6947","null","null","null","null","null" "Reduction of stearoyl-CoA desaturase (SCD) contributes muscle atrophy through the excess endoplasmic reticulum stress in chronic kidney disease","Reduction of stearoyl-CoA desaturase (SCD) contributes muscle atrophy through the excess endoplasmic reticulum stress in chronic kidney disease","Yuki Niida, Masashi Masuda, Yuichiro Adachi, Aika Yoshizawa, Hirokazu Ohminami, Yuki Mori, Kohta Ohnishi, Hisami Okumura, Takayuki Uchida, Takeshi Nikawa, Hironori Yamamoto, Makoto Miyazaki, Yutaka Taketani","Yuki Niida, Masashi Masuda, Yuichiro Adachi, Aika Yoshizawa, Hirokazu Ohminami, Yuki Mori, Kohta Ohnishi, Hisami Okumura, Takayuki Uchida, Takeshi Nikawa, Hironori Yamamoto, Makoto Miyazaki, Yutaka Taketani","null","
Skeletal muscle atrophy is associated with mortality and poor prognosis in patients with chronic kidney disease (CKD). However, underlying mechanism by which CKD causes muscle atrophy has not been completely understood. The quality of lipids (lipoquality), which is defined as the functional features of diverse lipid species, has recently been recognized as the pathology of various diseases. In this study, we investigated the roles of the stearoyl-CoA desaturase (SCD), which catalyzes the conversion of saturated fatty acids into monounsaturated fatty acids, in skeletal muscle on muscle atrophy in CKD model animals. In comparison to control rats, CKD rats decreased the SCD activity and its gene expression in atrophic gastrocnemius muscle. Next, oleic acid blocked the reduction of the thickness of C2C12 myotubes and the increase of the endoplasmic reticulum stress induced by SCD inhibitor. Furthermore, endoplasmic reticulum stress inhibitor ameliorated CKD-induced muscle atrophy (the weakness of grip strength and the decrease of muscle fiber size of gastrocnemius muscle) in mice and the reduction of the thickness of C2C12 myotubes by SCD inhibitor. These results suggest that the repression of SCD activity causes muscle atrophy through excessive endoplasmic reticulum stress in CKD.
","Skeletal muscle atrophy is associated with mortality and poor prognosis in patients with chronic kidney disease (CKD). However, underlying mechanism by which CKD causes muscle atrophy has not been completely understood. The quality of lipids (lipoquality), which is defined as the functional features of diverse lipid species, has recently been recognized as the pathology of various diseases. In this study, we investigated the roles of the stearoyl-CoA desaturase (SCD), which catalyzes the conversion of saturated fatty acids into monounsaturated fatty acids, in skeletal muscle on muscle atrophy in CKD model animals. In comparison to control rats, CKD rats decreased the SCD activity and its gene expression in atrophic gastrocnemius muscle. Next, oleic acid blocked the reduction of the thickness of C2C12 myotubes and the increase of the endoplasmic reticulum stress induced by SCD inhibitor. Furthermore, endoplasmic reticulum stress inhibitor ameliorated CKD-induced muscle atrophy (the weakness of grip strength and the decrease of muscle fiber size of gastrocnemius muscle) in mice and the reduction of the thickness of C2C12 myotubes by SCD inhibitor. These results suggest that the repression of SCD activity causes muscle atrophy through excessive endoplasmic reticulum stress in CKD.
","null","null","2020","Journal of Clinical Biochemistry and Nutrition","Journal of Clinical Biochemistry and Nutrition","Vol.67","No.2","179","187","eng","true","null","scientific_journal","null","null","10.3164/jcbn.20-24","1880-5086","null","https://ci.nii.ac.jp/naid/130007894915/","null","null","null" "Association of increased renal Cyp24a1 gene expression with low plasma 1,25-dihydroxyvitamin D levels in rats with streptozotocin-induced diabetes.","Association of increased renal Cyp24a1 gene expression with low plasma 1,25-dihydroxyvitamin D levels in rats with streptozotocin-induced diabetes.","Mari Tajiri, Otoki Nakahashi, Tomohiro Kagawa, Masashi Masuda, Hirokazu Ohminami, Masayuki Iwano, Eiji Takeda, Yutaka Taketani, Hironori Yamamoto","Mari Tajiri, Otoki Nakahashi, Tomohiro Kagawa, Masashi Masuda, Hirokazu Ohminami, Masayuki Iwano, Eiji Takeda, Yutaka Taketani, Hironori Yamamoto","null","Decreases in plasma vitamin D concentrations have been reported in diabetes, although the mechanism involved in this decrease is unclear. Here, we investigated the association between Cyp24a1, a vitamin D catabolic enzyme, and abnormalities in vitamin D metabolism in streptozotocin-induced diabetes rats, an animal model of type 1 diabetes. Plasma 1,25-dihydroxyvitamin D [1,25(OH)2D] levels were significantly lower in streptozotocin-induced diabetes rats and renal Cyp24a1 mRNA expression levels were increased. Western blotting analysis of streptozotocin-induced diabetes rats kidney tissues with anti-CYP24A1 antibody showed a strong signal around 40 kDa, which differs from the predicted 50-55 kDa molecular weight for full-length Cyp24a1 and could represent the Cyp24a1-splicing variant that lacks exons 1 and 2. We observed high levels of renal Cyp24a1-splicing variant mRNA expression in streptozotocin-induced diabetes rats. We also confirmed transcriptional up-regulation of endogenous Cyp24a1 mRNA expression through glucocorticoid receptors by glucocorticoid in opossum kidney proximal cells. Taken together, our results indicated that high Cyp24a1 expression levels may play a role in the decrease of plasma 1,25(OH)2D levels in streptozotocin-induced diabetes rats. High plasma corticosterone levels in diabetes may affect transcriptional regulation to promote increases in Cyp24a1 expression.","Decreases in plasma vitamin D concentrations have been reported in diabetes, although the mechanism involved in this decrease is unclear. Here, we investigated the association between Cyp24a1, a vitamin D catabolic enzyme, and abnormalities in vitamin D metabolism in streptozotocin-induced diabetes rats, an animal model of type 1 diabetes. Plasma 1,25-dihydroxyvitamin D [1,25(OH)2D] levels were significantly lower in streptozotocin-induced diabetes rats and renal Cyp24a1 mRNA expression levels were increased. Western blotting analysis of streptozotocin-induced diabetes rats kidney tissues with anti-CYP24A1 antibody showed a strong signal around 40 kDa, which differs from the predicted 50-55 kDa molecular weight for full-length Cyp24a1 and could represent the Cyp24a1-splicing variant that lacks exons 1 and 2. We observed high levels of renal Cyp24a1-splicing variant mRNA expression in streptozotocin-induced diabetes rats. We also confirmed transcriptional up-regulation of endogenous Cyp24a1 mRNA expression through glucocorticoid receptors by glucocorticoid in opossum kidney proximal cells. Taken together, our results indicated that high Cyp24a1 expression levels may play a role in the decrease of plasma 1,25(OH)2D levels in streptozotocin-induced diabetes rats. High plasma corticosterone levels in diabetes may affect transcriptional regulation to promote increases in Cyp24a1 expression.","null","null","2019-10-30","Journal of Clinical Biochemistry and Nutrition","Journal of Clinical Biochemistry and Nutrition","Vol.66","No.1","49","56","eng","true","null","scientific_journal","null","null","10.3164/jcbn.19-79","0912-0009","null","null","null","null","null"