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Deng JL, Tang MJ, Su XX, Ye YT, Wei JY, Chen ZX, Qin YM. Rapid Kinetic Interactions of Sugar and Sugar Alcohol with Sweet Taste Receptors on Live Cells Using Stopped-Flow Spectroscopy. J Agric Food Chem 2023; 71:14731-14741. [PMID: 37773006 DOI: 10.1021/acs.jafc.3c05144] [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] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/30/2023]
Abstract
The subjective measurement of the dynamic perception of sweetness is a problem in food science. Herein, the rapid interactions of sugars and sugar alcohols with sweet taste receptors on living cells on a millisecond timescale were studied via stopped-flow fluorescence spectroscopy. According to the rapid-kinetic parameters, sweeteners were divided into two groups. Sweeteners in group I disrupted the hydrogen bond network structure of water, and the apparent rate constant (kobs) was in the range of 0.45-0.6 s-1. Sweeteners in group II promoted the hydrogen bond formation of water, and the kobs was mostly in the range of 0.6-0.75 s-1. For most sweeteners, the kobs of cell responses was negatively correlated with the apparent specific volume of sweeteners. The differences in the cellular responses may be attributed to the disturbance in the water structure. Experimental results showed that the kinetic parameters of sweet cell responses reflected the dynamic perception of sweetness. Rapid kinetics, solution thermodynamic analysis, and water structure analysis enriched the physicochemical study of the sweetness mechanism and can be used to objectively evaluate the dynamic perception of sweetness.
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Affiliation(s)
- Jun-Ling Deng
- Molecular Food Science Laboratory, College of Food & Biology Engineering, Zhejiang Gongshang University, Hangzhou 310018, China
| | - Meng-Jie Tang
- Molecular Food Science Laboratory, College of Food & Biology Engineering, Zhejiang Gongshang University, Hangzhou 310018, China
| | - Xiao-Xia Su
- Molecular Food Science Laboratory, College of Food & Biology Engineering, Zhejiang Gongshang University, Hangzhou 310018, China
- COFCO Nutrition and Health Research Institute Co., Ltd., Beijing 102209, China
| | - Yu-Tong Ye
- Molecular Food Science Laboratory, College of Food & Biology Engineering, Zhejiang Gongshang University, Hangzhou 310018, China
| | - Jie-Ying Wei
- Molecular Food Science Laboratory, College of Food & Biology Engineering, Zhejiang Gongshang University, Hangzhou 310018, China
| | - Zhong-Xiu Chen
- Molecular Food Science Laboratory, College of Food & Biology Engineering, Zhejiang Gongshang University, Hangzhou 310018, China
| | - Yu-Mei Qin
- Molecular Food Science Laboratory, College of Food & Biology Engineering, Zhejiang Gongshang University, Hangzhou 310018, China
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Li Y, Niu HM, Guo YX, Ma XK, Hu MX, Han JZ, Qin YM. Crypt-like patterned electrospun nanofibrous membrane and probiotics promote intestinal epithelium models close to tissues. Appl Microbiol Biotechnol 2023:10.1007/s00253-023-12602-4. [PMID: 37266585 DOI: 10.1007/s00253-023-12602-4] [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] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Revised: 05/14/2023] [Accepted: 05/19/2023] [Indexed: 06/03/2023]
Abstract
In vitro intestinal epithelium models have drawn great attention to investigating intestinal biology in recent years. However, the difficulty to maintain the normal physiological status of primary intestinal epithelium in vitro limits the applications. Here, we designed patterned electrospun polylactic acid (PLA) nanofibrous membranes with crypt-like topography and mimic ECM fibrous network to support crypt culture and construct in vitro intestinal epithelium models. The patterned electrospun PLA nanofibrous membranes modified with Matrigels at 0 °C showed high biocompatibility and promoted cell growth and proliferation. The constructed duodenum epithelium models and colon epithelium models on the patterned electrospun PLA nanofibrous membranes expressed the typical differentiation markers of intestinal epithelia and the gene expression levels were close to the original tissues, especially with the help of probiotics. The constructed intestinal epithelium models could be used to assess probiotic adhesion and colonization, which were verified to show significant differences with the Caco-2 cell models due to the different cell types. These findings provide new insights and a better understanding of the roles of biophysical, biochemical, and biological signals in the construction of in vitro intestinal epithelium models as well as the potential applications of these models in the study of host-gut microbes interactions. KEY POINTS: • Patterned electrospun scaffold has crypt-like topography and ECM nanofibrous network. • Matrigels at 0°C modify scaffolds more effectively than at 37°C. • Synergy of biomimic scaffold and probiotics makes in vitro model close to tissue.
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Affiliation(s)
- Yue Li
- Food Safety Key Laboratory of Zhejiang Province, School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, 310018, China
| | - Hong-Mei Niu
- Food Safety Key Laboratory of Zhejiang Province, School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, 310018, China
| | - Ya-Xin Guo
- Food Safety Key Laboratory of Zhejiang Province, School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, 310018, China
| | - Xue-Ke Ma
- Food Safety Key Laboratory of Zhejiang Province, School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, 310018, China
| | - Meng-Xin Hu
- Food Safety Key Laboratory of Zhejiang Province, School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, 310018, China.
| | - Jian-Zhong Han
- Food Safety Key Laboratory of Zhejiang Province, School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, 310018, China
| | - Yu-Mei Qin
- Food Safety Key Laboratory of Zhejiang Province, School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, 310018, China
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Li Y, Hu MX, Yan M, Guo YX, Ma XK, Han JZ, Qin YM. Intestinal models based on biomimetic scaffolds with an ECM micro-architecture and intestinal macro-elasticity: close to intestinal tissue and immune response analysis. Biomater Sci 2023; 11:567-582. [PMID: 36484321 DOI: 10.1039/d2bm01051h] [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] [Indexed: 12/12/2022]
Abstract
The synergetic biological effect of scaffolds with biomimetic properties including the ECM micro-architecture and intestinal macro-mechanical properties on intestinal models in vitro remains unclear. Here, we investigate the profitable role of biomimetic scaffolds on 3D intestinal epithelium models. Gelatin/bacterial cellulose nanofiber composite scaffolds crosslinked by the Maillard reaction are tuned to mimic the chemical component, nanofibrous network, and crypt architecture of intestinal ECM collagen and the stability and mechanical properties of intestinal tissue. In particular, scaffolds with comparable elasticity and viscoelasticity of intestinal tissue possess the highest biocompatibility and best cell proliferation and differentiation ability, which makes the intestinal epithelium models closest to their counterpart intestinal tissues. The constructed duodenal epithelium models and colon epithelium models are utilized to assess the immunobiotics-host interactions, and both of them can sensitively respond to foreign microorganisms, but the secretion levels of cytokines are intestinal cell specific. The results demonstrate that probiotics alleviate the inflammation and cell apoptosis induced by Escherichia coli, indicating that probiotics can protect the intestinal epithelium from damage by inhibiting the adhesion and invasion of E. coli to intestinal cells. The designed biomimetic scaffolds can serve as powerful tools to construct in vitro intestinal epithelium models, providing a convenient platform to screen intestinal anti-inflammatory components and even to assess other physiological functions of the intestine.
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Affiliation(s)
- Yue Li
- Food Safety Key Laboratory of Zhejiang Province, School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou 310018, China.
| | - Meng-Xin Hu
- Food Safety Key Laboratory of Zhejiang Province, School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou 310018, China.
| | - Ming Yan
- School of Automation, Hangzhou Dianzi University, Hangzhou 310018, China
| | - Ya-Xin Guo
- Food Safety Key Laboratory of Zhejiang Province, School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou 310018, China.
| | - Xue-Ke Ma
- Food Safety Key Laboratory of Zhejiang Province, School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou 310018, China.
| | - Jian-Zhong Han
- Food Safety Key Laboratory of Zhejiang Province, School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou 310018, China.
| | - Yu-Mei Qin
- Food Safety Key Laboratory of Zhejiang Province, School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou 310018, China.
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Qin YM, Li P, Mu XP, Li ZM, Sun C, Xue WL, Sun J, Bai JJ, Zhu YC, Wang MJ. Histone deacetylase 6 promotes skin wound healing by regulating fibroblast migration and differentiation in aged mice. Sheng Li Xue Bao 2022; 74:979-992. [PMID: 36594386] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Skin wound healing tends to slow down with aging, which is detrimental to both minor wound recovery in daily life and the recovery after surgery. The aim of current study was to explore the effect of histone deacetylase 6 (HDAC6) on wound healing during aging. Cultured human dermal fibroblasts (HDFs) and mouse full-thickness skin wound model were used to explore the functional changes of replicative senescent dermal fibroblasts and the effect of aging on skin wound healing. Scratch wound healing assay revealed significantly decreased migration speed of senescent HDFs, and BrdU incorporation assay indicated their considerably retardant proliferation. The protein expression levels of collagen and HDAC6 were significantly decreased in both senescent HDFs and skin tissues from aged mice. HDAC6 activity inhibition with highly selective inhibitor tubastatin A (TsA) or HDAC6 knockdown with siRNA decreased the migration speed of HDFs and considerably suppressed fibroblast differentiation induced by transforming growth factor-β1 (TGF-β1), which suggests the involvement of HDAC6 in regulating fundamental physiological activities of dermal fibroblasts. In vivo full-thickness skin wound healing was significantly delayed in young HDAC6 knockout mice when compared with young wild type mice. In addition, the wound healing was significantly slower in aged wild type mice than that in young wild type mice, and became even worse in aged HDAC6 knockout aged mice. Compared to the aged wild type mice, aged HDAC6 knockout mice exhibited delayed angiogenesis, reduced collagen synthesis, and decreased collagen deposition in skin wounds. Together, these results suggest that delayed skin wound healing in aged mice is associated with impaired fibroblast function. Adequate expression and activity of HDAC6 are required for fibroblasts migration and differentiation.
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Affiliation(s)
- Yu-Mei Qin
- Shanghai Key Laboratory of Bioactive Small Molecules and Shanghai Key Laboratory of Clinical Geriatric Medicine, the Innovative Research Team of High-level Local Universities in Shanghai, Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Fudan University, Shanghai 200032, China
| | - Ping Li
- Shanghai Key Laboratory of Bioactive Small Molecules and Shanghai Key Laboratory of Clinical Geriatric Medicine, the Innovative Research Team of High-level Local Universities in Shanghai, Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Fudan University, Shanghai 200032, China
| | - Xue-Pan Mu
- Shanghai Key Laboratory of Bioactive Small Molecules and Shanghai Key Laboratory of Clinical Geriatric Medicine, the Innovative Research Team of High-level Local Universities in Shanghai, Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Fudan University, Shanghai 200032, China
| | - Zhi-Ming Li
- Shanghai Key Laboratory of Bioactive Small Molecules and Shanghai Key Laboratory of Clinical Geriatric Medicine, the Innovative Research Team of High-level Local Universities in Shanghai, Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Fudan University, Shanghai 200032, China
| | - Chen Sun
- Shanghai Key Laboratory of Bioactive Small Molecules and Shanghai Key Laboratory of Clinical Geriatric Medicine, the Innovative Research Team of High-level Local Universities in Shanghai, Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Fudan University, Shanghai 200032, China
| | - Wen-Long Xue
- Shanghai Key Laboratory of Bioactive Small Molecules and Shanghai Key Laboratory of Clinical Geriatric Medicine, the Innovative Research Team of High-level Local Universities in Shanghai, Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Fudan University, Shanghai 200032, China
| | - Jiao Sun
- Department of Endocrinology, Huadong Hospital Affiliated to Fudan University, Shanghai 200040, China
| | - Jiao-Jiao Bai
- Department of Endocrinology, Huadong Hospital Affiliated to Fudan University, Shanghai 200040, China
| | - Yi-Chun Zhu
- Shanghai Key Laboratory of Bioactive Small Molecules and Shanghai Key Laboratory of Clinical Geriatric Medicine, the Innovative Research Team of High-level Local Universities in Shanghai, Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Fudan University, Shanghai 200032, China
| | - Ming-Jie Wang
- Shanghai Key Laboratory of Bioactive Small Molecules and Shanghai Key Laboratory of Clinical Geriatric Medicine, the Innovative Research Team of High-level Local Universities in Shanghai, Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Fudan University, Shanghai 200032, China.
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Qin YM, Liao L, Deng XL, Huang J, Wei HY, Lin FQ. [Genetic Analysis and Prenatal Diagnosis of a Family with Hereditary Spherocytosis Caused by a Novel Compound Heterozygous Mutation of SPTB Gene]. Zhongguo Shi Yan Xue Ye Xue Za Zhi 2022; 30:552-558. [PMID: 35395996 DOI: 10.19746/j.cnki.issn.1009-2137.2022.02.039] [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] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
OBJECTIVE To investigate the clinical and genetic characteristics of a family with hereditary spherocytosis (HS), to clarify the cause of the disease, and to provide the basis for genetic counseling and prenatal diagnosis. METHODS The clinical data of proband and his parents were collected, and HS-related pathogenic genovariation of the proband was detected by high throughput sequencing. Suspected pathogenic mutation sites were verified by PCR-Sanger sequencing, and the fetus were conceived by a proband mother underwent prenatal diagnosis. RESULTS Clinical manifestations of the proband showed moderate anemia, mild splenomegaly, and jaundice (an indirect increase of bilirubin). The gene detection showed that the proband showed compound heterozygous mutations of SPTB gene c. 6095T > C (p.Leu2032Pro) and c. 6224A > G (p.Glu2075Gly), which was inherited from the asymptomatic mother and father, respectively. Both mutations were detected rarely in the common population. Prenatal diagnosis revealed that the fetus inherited a mutant gene of the mother. CONCLUSION The compound heterozygous mutations of SPTB genes c.6095T>C (p.Leu2032Pro) and c.6224A>G (p.Glu2075Gly) were the causes of the family disease, which provides a basis for family genetic counseling and prenatal diagnosis. This report is the first one found in the HGMD,1000G and EXAC database, which provides an addition to the mutation profile of the SPTB gene.
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Affiliation(s)
- Yu-Mei Qin
- Department of Clinical Laboratory Examination, The First Affiliated Hospital of Guangxi Medical University, Nanning 530021, Guangxi Zhuang Autonomous Region, China
| | - Lin Liao
- Department of Clinical Laboratory Examination, The First Affiliated Hospital of Guangxi Medical University, Nanning 530021, Guangxi Zhuang Autonomous Region, China
| | - Xue-Lian Deng
- Department of Clinical Laboratory Examination, The First Affiliated Hospital of Guangxi Medical University, Nanning 530021, Guangxi Zhuang Autonomous Region, China
| | - Jian Huang
- Department of Clinical Laboratory Examination, The First Affiliated Hospital of Guangxi Medical University, Nanning 530021, Guangxi Zhuang Autonomous Region, China
| | - Hong-Ying Wei
- Department of Pediatrics, The First Affiliated Hospital of Guangxi Medical University, Nanning 530021, Guangxi Zhuang Autonomous Region, China
| | - Fa-Quan Lin
- Department of Clinical Laboratory Examination, The First Affiliated Hospital of Guangxi Medical University, Nanning 530021, Guangxi Zhuang Autonomous Region, China,E-mail:
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Chen JL, Yang SW, Qin YM, Cheng XY. [Thrombocytopenia after interventional closure of congenital heart disease]. Zhonghua Xin Xue Guan Bing Za Zhi 2022; 50:191-194. [PMID: 35172468 DOI: 10.3760/cma.j.cn112148-20220104-00008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Affiliation(s)
- J L Chen
- Department of Cardiology, Children's Hospital of Nanjing Medical University, Nanjing 210008, China
| | - S W Yang
- Department of Cardiology, Children's Hospital of Nanjing Medical University, Nanjing 210008, China
| | - Y M Qin
- Department of Cardiology, Children's Hospital of Nanjing Medical University, Nanjing 210008, China
| | - X Y Cheng
- Department of Cardiology, Children's Hospital of Nanjing Medical University, Nanjing 210008, China
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Qin YM, Long D, Zhu X, Zhou ZX, Chai HF, Zhao CS. Erratum to: SYNTHESIS, CRYSTAL STRUCTURE, AND DFT STUDY OF A NEW COMPOUND 6-(2-FLUOROPHENYL)-N-(P-TOLYL)IMIDAZO[1,2-A]PYRIDINE-2-CARBOXAMIDE. J STRUCT CHEM+ 2020. [DOI: 10.1134/s0022476620070227] [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: 11/23/2022]
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Zhang LY, Qin YM, Yang SW. [Research progress in human induced pluripotent stem cells in pathogenesis of cardiomyopathy]. Zhonghua Er Ke Za Zhi 2020; 58:152-154. [PMID: 32102156 DOI: 10.3760/cma.j.issn.0578-1310.2020.02.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- L Y Zhang
- Department of Cardiology, Children's Hospital of Nanjing Medical University, Nanjing 210019, China
| | - Y M Qin
- Department of Cardiology, Children's Hospital of Nanjing Medical University, Nanjing 210019, China
| | - S W Yang
- Department of Cardiology, Children's Hospital of Nanjing Medical University, Nanjing 210019, China
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Qin YM, Zou X, Long D, Ji C, Zhao CS. The crystal structure of methyl 2-(benzylamino)-5-(benzyloxy)benzoate, C22H21NO3. Z KRIST-NEW CRYST ST 2019. [DOI: 10.1515/ncrs-2019-0420] [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] [Indexed: 11/15/2022]
Abstract
AbstractC22H21NO3, triclinic, P1̄ (no. 2), a = 5.757(3) Å, b = 12.106(5) Å, c = 13.139(6) Å, α = 93.725(12)°, β = 92.508(15)°, γ = 92.508(15)° V = 891.3(7) Å3, Z = 2, Rgt(F) = 0.0474, wRref(F2) = 0.1429, T = 296(2) K.
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Affiliation(s)
- Yu-Mei Qin
- School of Pharmaceutical Sciences, Guizhou University, Guiyang 550025, P.R. China
- Guizhou Engineering Laboratory for Synthetic Drugs, Guiyang 550025, P.R. China
| | - Xue Zou
- Clinical Research Center, Affiliated Hospital of Guizhou Medical University, Guiyang 550001, P.R. China
| | - Dan Long
- School of Pharmaceutical Sciences, Guizhou University, Guiyang 550025, P.R. China
- Guizhou Engineering Laboratory for Synthetic Drugs, Guiyang 550025, P.R. China
| | - Chun Ji
- School of Pharmaceutical Sciences, Guizhou University, Guiyang 550025, P.R. China
- Guizhou Engineering Laboratory for Synthetic Drugs, Guiyang 550025, P.R. China
| | - Chun-Shen Zhao
- School of Pharmaceutical Sciences, Guizhou University, Guiyang 550025, P.R. China
- Guizhou Engineering Laboratory for Synthetic Drugs, Guiyang 550025, P.R. China
- Key Laboratory of Guizhou for Fermentation Engineering and Biomedicine, Guiyang 550025, P.R. China
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Wang J, Dai GY, Qin YM. [Identification of an SCN5A mutation in a Chinese pedigree with a history of syncope]. Zhonghua Er Ke Za Zhi 2017; 55:393-394. [PMID: 28482396 DOI: 10.3760/cma.j.issn.0578-1310.2017.05.019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
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Li WL, Chen ML, Liu SS, Li GL, Gu TY, Liang P, Qin YM, Zhan YH, Quan Y, Zhang GH. Sweet preference modified by early experience in mice and the related molecular modulations on the peripheral pathway. J Mol Neurosci 2013; 51:225-36. [PMID: 23606220 DOI: 10.1007/s12031-013-0011-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2012] [Accepted: 04/01/2013] [Indexed: 12/19/2022]
Abstract
The sweet taste is of immense interest to scientists and has been intensively studied during the last two decades. However, the sweet preference modification and the related mechanisms are still unclear. In this study, we try to establish a mice model with manipulated sweet taste preference and explore the involved possible molecular mechanisms. The animals were exposed to acesulfame-K via maternal milk during lactation and the sweet preference tests were carried out when they grew to adulthood. Our results showed that the preference thresholds for sweet taste were increased in adults by early acesulfame-K exposure and the preference ratios for sweet tastants at low or preferred concentrations were decreased. Moreover, by means of qRT-PCR and Western blot, we observed the increased expression of leptin receptor Ob-Rb and downregulation of Gα-gustducin protein in the soft palate. Thereby, the sweet taste sensitivity may be modified by early sweetener experience during lactation. Along the peripheral sweet sensory pathway, the sweet regulator receptors Ob-Rb, CB1 and components of sweet transduction signal Gα-gustducin and T1R2 in both the soft palate and tongue may be cooperatively involved in the plastic development of sweet taste.
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Affiliation(s)
- Wei-Li Li
- Sensory Science Laboratory, School of Bioscience and Food Engineering, Changshu Institute of Technology, Nansanhuan Road 99, Changshu, 215500, Jiangsu Province, People's Republic of China
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Chen ML, Liu SS, Zhang GH, Quan Y, Zhan YH, Gu TY, Qin YM, Deng SP. Effects of early intraoral acesulfame-K stimulation to mice on the adult's sweet preference and the expression of α-gustducin in fungiform papilla. Chem Senses 2013; 38:447-55. [PMID: 23537561 DOI: 10.1093/chemse/bjt001] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [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: 02/02/2023] Open
Abstract
Exposure to artificial sweetener acesulfame-K (AK) at early development stages may influence the adult sweet preference and the periphery gustatory system. We observed that the intraoral AK stimulation to mice from postnatal day 4 (P4) to weaning decreased the preference thresholds for AK and sucrose solutions in adulthood, with the preference pattern unchanged. The preference scores were increased in the exposure group significantly when compared with the control group at a range of concentrations for AK or sucrose solution. Meanwhile, more α-Gustducin-labeled fungiform taste buds and cells in a single taste bud were induced from week 7 by the early intraoral AK stimulation. However, the growth in the number of α-Gustducin-positive taste bud or positive cell number per taste bud occurred only in the anterior region, the rostral 1-mm part, but not in the intermediate region, the caudal 4-mm part, of the anterior two-third of the tongue containing fungiform papillae. This work extends our previous observations and provides new information about the developmental and regional expression pattern of α-Gustducin in mouse fungiform taste bud under early AK-stimulated conditions.
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Affiliation(s)
- Meng-Ling Chen
- Sensory Science Laboratory, School of Bioscience and Food Engineering, Changshu Institute of Technology, Changshu 215500, PR China.
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Zhang GH, Chen ML, Liu SS, Zhan YH, Quan Y, Qin YM, Deng SP. Facilitation of the development of fungiform taste buds by early intraoral acesulfame-K stimulation to mice. J Neural Transm (Vienna) 2010; 117:1261-4. [DOI: 10.1007/s00702-010-0480-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2010] [Accepted: 08/30/2010] [Indexed: 10/19/2022]
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Qin YM, Shi JQ, Zhang GH, Deng SP, Wang TH. A reliable method to obtain cells of taste buds from fungiform papillae of mice. Acta Histochem 2008; 112:107-12. [PMID: 19013636 DOI: 10.1016/j.acthis.2008.09.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [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: 07/20/2008] [Revised: 09/05/2008] [Accepted: 09/15/2008] [Indexed: 11/16/2022]
Abstract
Taste buds consist of four kinds of cells which have distinct characteristics and play different roles in recognizing chemical compounds contained in foodstuffs. In this study we describe a procedure for separating viable taste bud cells from the fungiform papillae in mice. After sacrifice with CO(2), the mouse tongue was excised and immediately incubated in collagenase II and dispase II. The epithelium with fungiform papillae was then peeled away from underlying tissue and the anterior one-third region was incubated in a solution of 0.25% trypsin and 0.02M ethylene-diamine-tetraacetic acid (EDTA) for 8-12min. Following incubation, a cell suspension was obtained by mechanical dissociation. Cells in suspension were identified as taste bud cells by their morphology and by immunofluorescence. A 0.25% trypan blue staining demonstrated that nearly 90% of these cells remained viable. Micrographs from scanning electron microscopy illustrated that taste buds were dissociated from the fungiform papillae, while maintaining the integrity of the other part of the dissociated lingual epithelium during incubation. Such a method allows acquisition of viable taste cells and will aid further research in the study of gustatory characteristics.
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Affiliation(s)
- Yu-Mei Qin
- Zhejiang Gongshang University, Hangzhou, China
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Zhang GH, Zhang HY, Deng SP, Qin YM, Wang TH. Quantitative study of taste bud distribution within the oral cavity of the postnatal mouse. Arch Oral Biol 2008; 53:583-9. [PMID: 18294610 DOI: 10.1016/j.archoralbio.2008.01.005] [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: 07/19/2007] [Revised: 01/12/2008] [Accepted: 01/14/2008] [Indexed: 10/22/2022]
Abstract
The aim of this study was to investigate the age-related developmental changes of taste bud distribution within the subpopulations at different postnatal ages in the mouse oral cavity. Developmental changes of taste bud distribution on the soft palate, fungiform, foliate and circumvallate papillae in the mouse oral cavity were examined histologically at different postnatal ages. After paraffin embedding, complete serial sections at 10mum thickness were made and stained by routine hematoxylin-eosin staining methods. Digitised images for each section were examined carefully. The existence of a taste pore was used to identify mature taste buds. A two-way analysis of variance (group versus age) was used to analyse differences in taste bud number and characteristics for each of the developmental changes. An independent measures t-test was used to compare two means. No taste buds with pores were observed at birth within circumvallate and foliate papillae. However, 61% of the circumvallate and 58% of the foliate taste buds contained taste pores at 2 weeks after birth. In contrast, at birth, 55% of the taste buds on the soft palate and only 22% of the taste buds within fungiform papillae contained taste pores. Then, the number of mature taste buds (taste buds with pores) increased rapidly 1 week after birth, resulting in 90% of soft palate taste buds and 32% of fungiform taste buds containing taste pores. These results suggests that the earlier maturation of soft palate taste buds compared with the other populations in the oral cavity raises evidence of their significant role in the taste mechanism, especially in the early life of the mouse.
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Affiliation(s)
- Gen-Hua Zhang
- Sensory Science Lab, Department of Biological Science, Changshu Institute of Technology, 99 NanSanHuan Road, Changshu 215500, Jiangsu Province, PR China.
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Zhang GH, Zhang HY, Deng SP, Qin YM. Regional differences in taste bud distribution and alpha-gustducin expression patterns in the mouse fungiform papilla. Chem Senses 2008; 33:357-62. [PMID: 18296428 DOI: 10.1093/chemse/bjm093] [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: 11/14/2022] Open
Abstract
The regional differences between distribution patterns and alpha-gustducin expression patterns of the fungiform (FF) taste buds were investigated in the adult mouse, using hematoxylin-eosin staining and immunofluorescence histochemistry on the most anterior region of the tongue (the first millimeter) through the intermediate region of the tongue (the last 1-4 mm). Paraffin sections were prepared from the tip to posterior regions (anterior and intermediate region containing the FF taste buds) of the adult mouse tongue. Results indicate that there were significant regional differences in size and density of taste buds, the cell counts of the single taste bud, and the alpha-gustducin-immunoreactive taste buds between the 2 regions. The taste bud had a characteristic onion-like appearance, and the alpha-gustducin-immunoreactive cell was spindle shaped with elongated processes extending from the base to the pore of the taste buds. These results provide a detailed insight to better understand regional descriptions of mouse taste bud density and size and alpha-gustducin expression with the mouse model.
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Affiliation(s)
- Gen-Hua Zhang
- Sensory Science Laboratory, Department of Biological Science, Changshu Institute of Technology, 99 Nansanhuan Road, Changshu 215500, Jiangsu Province, People's Republic of China.
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Zhang GH, Zhang HY, Deng SP, Qin YM. Differentiation of alpha-gustducin in taste buds of the mouse soft palate and fungiform papillae. Acta Histochem 2007; 109:486-90. [PMID: 17698174 DOI: 10.1016/j.acthis.2007.05.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2007] [Revised: 05/09/2007] [Accepted: 05/16/2007] [Indexed: 11/17/2022]
Abstract
We used alpha-gustducin, a type II taste-cell-specific G protein, to investigate the onset of taste transduction and its relation to the development of the soft palate (SP) and fungiform (FF) papillae taste buds in the mouse. Paraffin wax embedded sections were prepared from the SP and anterior region of the tongue of the mouse from birth until postnatal day (PD) 63. No alpha-gustducin-immunoreactive cells were observed on the day of birth. One day later, alpha-gustducin was immunolocalised in taste buds with pores with a relatively higher frequency recorded in the SP as compared with the FF papillae. The immunoreactive cells were spindle shaped with elongated processes extending from the base to the pore of the taste buds. On PD 7, the number of taste buds containing alpha-gustducin-immunoreactive cells in the SP was three times greater than that of FF papillae. Our results indicate that taste transduction is essentially acquired from the time of birth. Moreover, the onset of taste transduction by the SP taste buds developed earlier than that achieved by taste buds in the FF papillae.
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Affiliation(s)
- Gen-Hua Zhang
- Laboratory of Sensory Science, Department of Biological Science, Changshu Institute of Technology, Nansanhuan Road, Changshu City, Jiangsu Province 215500, China.
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Bongcam V, MacDonald-Comber Petétot J, Mittendorf V, Robertson EJ, Leech RM, Qin YM, Hiltunen JK, Poirier Y. Importance of sequences adjacent to the terminal tripeptide in the import of a peroxisomal Candida tropicalis protein in plant peroxisomes. Planta 2000; 211:150-157. [PMID: 10923716 DOI: 10.1007/s004250000312] [Citation(s) in RCA: 5] [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] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The peroxisome targeting signal (PTS) required for import of the rat acyl-CoA oxidase (AOX; EC 1.3.3.6) and the Candida tropicalis multifunctional protein (MFP) in plant peroxisomes was assessed in transgenic Arabidopsis thaliana (L.) Heynh. The native rat AOX accumulated in peroxisomes in A. thaliana cotyledons and targeting was dependent on the presence of the C-terminal tripeptide S-K-L. In contrast, the native C. tropicalis MFP, containing the consensus PTS sequence A-K-I was not targeted to plant peroxisomes. Modification of the carboxy terminus to the S-K-L tripeptide also failed to deliver the MFP to peroxisomes while addition of the last 34 amino acids of the Brassica napus isocitrate lyase, containing the terminal tripeptide S-R-M, enabled import of the fusion protein into peroxisomes. These results underline the influence of the amino acids adjacent to the terminal tripeptide of the C. tropicalis MFP on peroxisomal targeting, even in the context of a protein having a consensus PTS sequence S-K-L.
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Affiliation(s)
- V Bongcam
- Institut d'Ecologie-Biologie et Physiologie Végétales, Université de Lausanne, Switzerland
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Novikov DK, Koivuranta KT, Helander HM, Filppula SA, Yagi AI, Qin YM, Hiltunen KJ. Enzymology of beta-oxidation of (poly)unsaturated fatty acids. Adv Exp Med Biol 2000; 466:301-9. [PMID: 10709656 DOI: 10.1007/0-306-46818-2_34] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
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Qin YM, Haapalainen AM, Kilpeläinen SH, Marttila MS, Koski MK, Glumoff T, Novikov DK, Hiltunen JK. Human peroxisomal multifunctional enzyme type 2. Site-directed mutagenesis studies show the importance of two protic residues for 2-enoyl-CoA hydratase 2 activity. J Biol Chem 2000; 275:4965-72. [PMID: 10671535 DOI: 10.1074/jbc.275.7.4965] [Citation(s) in RCA: 39] [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] [Indexed: 11/06/2022] Open
Abstract
Beta-oxidation of acyl-CoAs in mammalian peroxisomes can occur via either multifunctional enzyme type 1 (MFE-1) or type 2 (MFE-2), both of which catalyze the hydration of trans-2-enoyl-CoA and the dehydrogenation of 3-hydroxyacyl-CoA, but with opposite chiral specificity. Amino acid sequence alignment of the 2-enoyl-CoA hydratase 2 domain in human MFE-2 with other MFE-2s reveals conserved protic residues: Tyr-347, Glu-366, Asp-370, His-406, Glu-408, Tyr-410, Asp-490, Tyr-505, Asp-510, His-515, Asp-517, and His-532. To investigate their potential roles in catalysis, each residue was replaced by alanine in site-directed mutagenesis, and the resulting constructs were tested for complementation in a yeast. After additional screening, the wild type and noncomplementing E366A and D510A variants were expressed and characterized. The purified proteins have similar secondary structural elements, with the same subunit composition. The E366A variant had a k(cat)/K(m) value 100 times lower than that of the wild type MFE-2 at pH 5, whereas the D510A variant was inactive. Asp-510 was imbedded in a novel hydratase 2 motif found in the hydratase 2 proteins. The data show that the hydratase 2 reaction catalyzed by MFE-2 requires two protic residues, Glu-366 and Asp-510, suggesting that their catalytic role may be equivalent to that of the two catalytic residues of hydratase 1.
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Affiliation(s)
- Y M Qin
- Biocenter Oulu and Department of Biochemistry, University of Oulu, Box 3000, FIN-90014 Oulun Yliopisto, Finland
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Qin YM, Poutanen MH, Novikov DK. Substrate specificities of peroxisomal members of short-chain alcohol dehydrogenase superfamily: expression and characterization of dehydrogenase part of Candida tropicalis multifunctional enzyme. J Lipid Res 2000; 41:93-8. [PMID: 10627506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023] Open
Abstract
In addition to several other enzymes, the short-chain alcohol dehydrogenase superfamily includes a group of peroxisomal multifunctional enzymes involved in fatty acid and cholesterol side-chain beta-oxidation. Mammalian peroxisomal multifunctional enzyme type 2 (perMFE-2) is a 2-enoyl-CoA hydratase-2/(R)-3-hydroxyacyl-CoA dehydrogenase. As has been shown previously, perMFE-2 hydrates (24E)-3alpha,7alpha, 12alpha-trihydroxy-5beta-cholest-24-enoyl-CoA to (24R, 25R)-3alpha, 7alpha,12alpha,24xi-tetrahydroxy-5beta-choles tanoyl-CoA, which has been characterized as a physiological intermediate in cholic acid synthesis. Out of four possible stereoisomers of 3alpha,7alpha, 12alpha,24xi-tetrahydroxy-5beta-cholestanoyl-CoA , the mammalian perMFE-2 dehydrogenates only the (24R,25R)-isomer. The yeast peroxisomal multifunctional enzyme (MFE) was first described as 2-enoyl-CoA hydratase-2/(R)-3-hydroxyacyl-CoA dehydrogenase. To investigate the stereospecificity of yeast peroxisomal MFE, the two dehydrogenase domains of C. tropicalis MFE were expressed in E. coli as a 65 kDa recombinant protein. This protein catalyzes the dehydrogenation of straight-chain (R)-3-hydroxyacyl-CoAs, but it is devoid of (S)-3-hydroxyacyl-CoA dehydrogenase and 2-enoyl-CoA hydratase activities. The protein dehydrogenates (24R,25R)- and (24R, 25S)-isomers of 3alpha,7alpha, 12alpha, 24xi-tetrahydroxy-5beta-cholestanoyl-CoA. Interestingly, the protein also shows 17beta-estradiol dehydrogenase activity. As a monofunctional (R)-specific 3-hydroxyacyl-CoA dehydrogenase is currently unavailable, this recombinant enzyme can be used to study the stereochemistry of bile acid synthesis.
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Affiliation(s)
- Y M Qin
- Biocenter Oulu, University of Oulu, FIN-90570 Oulu, Finland
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Qin YM, Marttila MS, Haapalainen AM, Siivari KM, Glumoff T, Hiltunen JK. Yeast peroxisomal multifunctional enzyme: (3R)-hydroxyacyl-CoA dehydrogenase domains A and B are required for optimal growth on oleic acid. J Biol Chem 1999; 274:28619-25. [PMID: 10497229 DOI: 10.1074/jbc.274.40.28619] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [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: 11/06/2022] Open
Abstract
The yeast peroxisomal (3R)-hydroxyacyl-CoA dehydrogenase/2-enoyl-CoA hydratase 2 (multifunctional enzyme type 2; MFE-2) has two N-terminal domains belonging to the short chain alcohol dehydrogenase/reductase superfamily. To investigate the physiological roles of these domains, here called A and B, Saccharomyces cerevisiae fox-2 cells (devoid of Sc MFE-2) were taken as a model system. Gly(16) and Gly(329) of the S. cerevisiae A and B domains, corresponding to Gly(16), which is mutated in the human MFE-2 deficiency, were mutated to serine and cloned into the yeast expression plasmid pYE352. In oleic acid medium, fox-2 cells transformed with pYE352:: ScMFE-2(aDelta) and pYE352::ScMFE-2(bDelta) grew slower than cells transformed with pYE352::ScMFE-2, whereas cells transformed with pYE352::ScMFE-2(aDeltabDelta) failed to grow. Candida tropicalis MFE-2 with a deleted hydratase 2 domain (Ct MFE- 2(h2Delta)) and mutational variants of the A and B domains (Ct MFE- 2(h2DeltaaDelta), Ct MFE- 2(h2DeltabDelta), and Ct MFE- 2(h2DeltaaDeltabDelta)) were overexpressed and characterized. All proteins were dimers with similar secondary structure elements. Both wild type domains were enzymatically active, with the B domain showing the highest activity with short chain and the A domain with medium and long chain (3R)-hydroxyacyl-CoA substrates. The data show that the dehydrogenase domains of yeast MFE-2 have different substrate specificities required to allow the yeast to propagate optimally on fatty acids as the carbon source.
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Affiliation(s)
- Y M Qin
- Biocenter Oulu, Department of Biochemistry, University of Oulu, FIN-90570 Oulu, Finland
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Qin YM, Haapalainen AM, Conry D, Cuebas DA, Hiltunen JK, Novikov DK. Recombinant 2-enoyl-CoA hydratase derived from rat peroxisomal multifunctional enzyme 2: role of the hydratase reaction in bile acid synthesis. Biochem J 1997; 328 ( Pt 2):377-82. [PMID: 9371691 PMCID: PMC1218931 DOI: 10.1042/bj3280377] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.2] [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: 02/05/2023]
Abstract
Rat liver peroxisomes contain two multifunctional enzymes: (1) perMFE-1 [2-enoyl-CoA hydratase 1/Delta3,Delta2-enoyl-CoA isomerase/(S)-3-hydroxyacyl-CoA dehydrogenase] and (2) perMFE-2 [2-enoyl-CoA hydratase 2/(R)-3-hydroxyacyl-CoA dehydrogenase]. To investigate the role of the hydratase activity of perMFE-2 in beta-oxidation, a truncated version of perMFE-2 was expressed in Escherichia coli as a recombinant protein. The protein catalyses the hydration of straight-chain (2E)-enoyl-CoAs to (3R)-hydroxyacyl-CoAs, but it is devoid of hydratase 1 [(2E)-enoyl-CoA to (3S)-hydroxyacyl-CoA] and (3R)-hydroxyacyl-CoA dehydrogenase activities. The purified enzyme (46 kDa hydratase 2) can be stored as an active enzyme for at least half a year. The recombinant enzyme hydrates (24E)-3alpha,7alpha,12alpha-trihydroxy- 5beta-cholest-24-enoyl-CoA to (24R,25R)-3alpha,7alpha,12alpha, 24-tetrahydroxy-5beta-cholestanoyl-CoA, which has previously been characterized as a physiological intermediate in bile acid synthesis. The stereochemistry of the products indicates that the hydration reaction catalysed by the enzyme proceeds via a syn mechanism. A monofunctional 2-enoyl-CoA hydratase 2 has not been observed as a wild-type protein. The recombinant 46 kDa hydratase 2 described here survives in a purified form under storage, thus being the first protein of this type amenable to application as a tool in metabolic studies.
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Affiliation(s)
- Y M Qin
- Biocenter Oulu, University of Oulu, Linnanmaa, FIN-90570 Oulu, Finland
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Qin YM, Poutanen MH, Helander HM, Kvist AP, Siivari KM, Schmitz W, Conzelmann E, Hellman U, Hiltunen JK. Peroxisomal multifunctional enzyme of beta-oxidation metabolizing D-3-hydroxyacyl-CoA esters in rat liver: molecular cloning, expression and characterization. Biochem J 1997; 321 ( Pt 1):21-8. [PMID: 9003397 PMCID: PMC1218032 DOI: 10.1042/bj3210021] [Citation(s) in RCA: 79] [Impact Index Per Article: 2.9] [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: 02/03/2023]
Abstract
In the present study we have cloned and characterized a novel rat peroxisomal multifunctional enzyme (MFE) named perMFE-II. The purified 2-enoyl-CoA hydratase 2 with an M(r) of 31500 from rat liver [Malila, Siivari, Mäkelä, Jalonen, Latipää, Kunau and Hiltunen (1993) J. Biol. Chem. 268, 21578-21585] was subjected to tryptic fragmentation and the resulting peptides were isolated and sequenced. Surprisingly, the full-length cDNA, amplified by PCR, had an open reading frame of 2205 bp encoding a polypeptide with a predicted M(r) of 79,331 and contained a potential peroxisomal targeting signal in the C-terminus (Ala-Lys-Leu). The sequenced peptide fragments of hydratase 2 gave a full match in the middle portion of the cDNA-derived amino acid sequence. The predicted amino acid sequence showed a high degree of similarity with pig 17 beta-hydroxysteroid dehydrogenase type IV and MFE of yeast peroxisomal beta-oxidation. Recombinant perMFE-II (produced in Pichia pastoris) had 2-enoyl-CoA hydratase 2 and D-specific 3-hydroxyacyl-CoA dehydrogenase activities and was catalytically active with several straight-chain trans-2-enoyl-CoA, 2-methyltetradecenoyl-CoA and pristenoyl-CoA esters. The results showed that in addition to an earlier described multifunctional isomerase-hydratase-dehydrogenase enzyme from rat liver peroxisomes (perMFE-I), another MFE exists in rat liver peroxisomes. They both catalyse sequential hydratase and dehydrogenase reactions of beta-oxidation but through reciprocal stereochemical courses.
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Affiliation(s)
- Y M Qin
- Biocenter Oulu, University of Oulu, Finland
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Abstract
Peroxisomes are capable of oxidizing a variety of substrates including (poly)unsaturated enoyl-CoA esters. The beta-oxidation of unsaturated enoyl-CoA esters in peroxisomes, and also in mitochondria, is not just chain-shortening but also involves the metabolizing of pre-existing carbon-to-carbon double bonds. In addition to the enzymes of the beta-oxidation spiral itself, this metabolism requires the participation of auxiliary enzymes: delta 3, delta 2-enoyl-CoA isomerase; 2,4-dienoyl-CoA reductase; 2-enoyl-CoA hydratase 2 or 3-hydroxyacyl-CoA epimerase; and delta 3,5 delta 2,4-dienoyl-CoA isomerase. Many of these enzymes are present as isoforms, and can be found located in multiple subcellular compartments, for example, peroxisomes, mitochondria or the endoplasmic reticulum, while some of the activities are integral parts of multifunctional enzymes of beta-oxidation systems.
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Huang C, Qin YM, Liang NC. Effects of aprotinin in platelet aggregation and cytosolic free calcium in swine platelets. Zhongguo Yao Li Xue Bao 1993; 14:565-567. [PMID: 7516610] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Aprotinin inhibited platelet aggregation induced by thrombin (0.25 U.ml-1) with IC50 200 kIU.ml-1, and inhibited the rise of cytosolic free calcium concentration in platelets stimulated by thrombin (0.1 U.ml-1) in the absence and in the presence of Ca2+ 0.5 mmol.L-1 (IC50 117 and 50 kIU.ml-1, respectively), but had no effect on the amounts of actin and myosin heavy chain associated with cytoskeletons. These suggest that aprotinin is an anti-platelet agent and may exert its action through inhibiting the Ca2+ flux.
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Affiliation(s)
- C Huang
- Department of Medical Biochemistry, Guangdong Medical College, Zhanjiang, China
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Lu JB, Qin YM. Correlation between high salt intake and mortality rates for oesophageal and gastric cancers in Henan Province, China. Int J Epidemiol 1987; 16:171-6. [PMID: 3610444 DOI: 10.1093/ije/16.2.171] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
This paper concerns the analysis of the rank correlation between salt quantity sold (SQS) to the Henan inhabitants from 1964-66, 1974-76 and their mortality rates for oesophageal cancer and gastric cancer in 1974-76. Both sets of data were in agreement with each other, and were consistent with the geographical distribution of these two diseases. Correlation coefficients derived from such analysis were as follows: oesophageal cancer in males--0.61 (p less than 0.01); and in females--0.47 (p less than 0.01); gastric cancer in males--0.63 (p less than 0.01), and in females--0.54 (p less than 0.01). SQS was positively correlated with mortality rates for oesophageal cancer and gastric cancer whereas it was not correlated with cancers of the liver, lung cancer and leukaemia in males and cervical cancer in females. There was no significant difference between the relevant parameters of the high incidence area and those of the low incidence area. These findings show that salt intake such as salty vegetables and cured meat might be one of the risk factors inducing oesophageal and gastric cancers.
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Abstract
Data on morbidity and mortality from oesophageal cancer (EC) over the 25 years from 1959-1983 indicate that this malignancy has been the commonest cause of death in Linxian (LX) county during that period, accounting for 16% of deaths from all causes and 65% of deaths from cancer. Whereas incidence and mortality of EC were high but stable during this period, a decline in mortality has been noted recently in younger age groups, coinciding with an improvement in nutritional standards. Cohort analysis for the period 1879-1954 demonstrates mortality peaks among individuals born late in the last century and early in the present one. It also shows that a decline in mortality appears to have started among natives of the county born during the period 1935-1954.
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