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Wu S, Wang R, Zhao Y, Ma X, Wu M, Yan X, He J. The relationship between self-rated health and objective health status: a population-based study. BMC Public Health 2013; 13:320. [PMID: 23570559 PMCID: PMC3637052 DOI: 10.1186/1471-2458-13-320] [Citation(s) in RCA: 459] [Impact Index Per Article: 38.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2012] [Accepted: 04/01/2013] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Self-rated health (SRH), a subjective assessment of health status, is extensively used in the public health field. However, whether SRH can reflect the objective health status is still debatable. We aim to reveal the relationship between SRH and objective health status in the general population. METHODS We assessed the relationship between SRH and objective health status by examining the prevalence of diseases, laboratory parameters, and some health-related factors in different SRH groups. Data were collected from 18,000 residents randomly sampled from the general population in five cities of China (3,600 in each city). SRH was assessed by a single-item health measure with five options: "very good," "good," "fair," "bad," and "very bad." The differences in prevalence of diseases, laboratory parameters, and health-related factors between the "healthy" (very good plus good), "relatively healthy" (fair), and "unhealthy" (bad plus very bad) groups were examined. The odds ratios (ORs) referenced by the healthy group were calculated using logistic regression analysis. RESULTS The prevalence of all diseases was associated with poorer SRH. The tendency was more prominent in cardio-cerebral vascular diseases, visual impairment, and mental illnesses with larger ORs. Residents with abnormalities in laboratory parameters tended to have poorer SRH, with ORs ranging from 1.62 (for triglyceride) to 3.48 (for hemoglobin among men) in a comparison of the unhealthy and healthy groups. Most of the health-related factors regarded as risks were associated with poorer SRH. Among them, life and work pressure, poor spiritual status, and poor quality of interpersonal relationships were the most significant factors. CONCLUSIONS SRH is consistent with objective health status and can serve as a global measure of health status in the general population.
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Zhang H, He C, Yan X, Mirshahi T, Logothetis DE. Activation of inwardly rectifying K+ channels by distinct PtdIns(4,5)P2 interactions. Nat Cell Biol 1999; 1:183-8. [PMID: 10559906 DOI: 10.1038/11103] [Citation(s) in RCA: 296] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Direct interactions of phosphatidylinositol-4,5-bisphosphate (PtdIns(4,5)P2) with inwardly rectifying potassium channels are stronger with channels rendered constitutively active by binding to PtdIns(4,5)P2, such as IRK1, than with G-protein-gated channels (GIRKs). As a result, PtdIns(4,5)P2 alone can activate IRK1 but not GIRKs, which require extra gating molecules such as the beta gamma subunits of G proteins or sodium ions. Here we identify two conserved residues near the inner-membrane interface of these channels that are critical in interactions with PtdIns(4,5)P2. Between these two arginines, a conservative change of isoleucine residue 229 in GIRK4 to the corresponding leucine found in IRK1 strengthens GIRK4-PtdIns(4,5)P2 interactions, eliminating the need for extra gating molecules. A negatively charged GIRK4 residue, two positions away from the most strongly interacting arginine, mediates stimulation of channel activity by sodium by strengthening channel-PtdIns(4,5)P2 interactions. Our results provide a mechanistic framework for understanding how distinct gating mechanisms of inwardly rectifying potassium channels allow these channels to subserve their physiological roles.
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Yan X, Chuda Y, Suzuki M, Nagata T. Fucoxanthin as the major antioxidant in Hijikia fusiformis, a common edible seaweed. Biosci Biotechnol Biochem 1999; 63:605-7. [PMID: 10227153 DOI: 10.1271/bbb.63.605] [Citation(s) in RCA: 242] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The radical scavenging activity of Japanese edible seaweeds was screened by the DPPH (1-diphenyl-2-picrylhydrazyl) assay to evaluate the DPPH radical scavenging activity in organic extracts. The fresh brown alga Hijikia fusiformis showed the strongest DPPH radical scavenging activity, followed by Undaria pinnatifida and Sargassum fulvellum. The major active compound from Hijikia fusiformis in its acetone extract was identified as fucoxanthin by 13C-NMR spectroscopy.
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Roche TE, Baker JC, Yan X, Hiromasa Y, Gong X, Peng T, Dong J, Turkan A, Kasten SA. Distinct regulatory properties of pyruvate dehydrogenase kinase and phosphatase isoforms. PROGRESS IN NUCLEIC ACID RESEARCH AND MOLECULAR BIOLOGY 2002; 70:33-75. [PMID: 11642366 DOI: 10.1016/s0079-6603(01)70013-x] [Citation(s) in RCA: 207] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The mammalian pyruvate dehydrogenase complex (PDC) plays central and strategic roles in the control of the use of glucose-linked substrates as sources of oxidative energy or as precursors in the biosynthesis of fatty acids. The activity of this mitochondrial complex is regulated by the continuous operation of competing pyruvate dehydrogenase kinase (PDK) and pyruvate dehydrogenase phosphatase (PDP) reactions. The resulting interconversion cycle determines the fraction of active (nonphosphorylated) pyruvate dehydrogenase (E1) component. Tissue-specific and metabolic state-specific control is achieved by the selective expression and distinct regulatory properties of at least four PDK isozymes and two PDP isozymes. The PDK isoforms are members of a family of serine kinases that are not structurally related to cytoplasmic Ser/Thr/Tyr kinases. The catalytic subunits of the PDP isoforms are Mg2+-dependent members of the phosphatase 2C family that has binuclear metal-binding sites within the active site. The dihydrolipoyl acetyltransferase (E2) and the dihydrolipoyl dehydrogenase-binding protein (E3BP) are multidomain proteins that form the oligomeric core of the complex. One or more of their three lipoyl domains (two in E2) selectively bind each PDK and PDP1. These adaptive interactions predominantly influence the catalytic efficiencies and effector control of these regulatory enzymes. When fatty acids are the preferred source of acetyl-CoA and NADH, feedback inactivation of PDC is accomplished by the activity of certain kinase isoforms being stimulated upon preferentially binding a lipoyl domain containing a reductively acetylated lipoyl group. PDC activity is increased in Ca2+-sensitive tissues by elevating PDP1 activity via the Ca2+-dependent binding of PDP1 to a lipoyl domain of E2. During starvation, the irrecoverable loss of glucose carbons is restricted by minimizing PDC activity due to high kinase activity that results from the overexpression of specific kinase isoforms. Overexpression of the same PDK isoforms deleteriously hinders glucose consumption in unregulated diabetes.
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Review |
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Qiao D, Ke C, Hu B, Luo J, Ye H, Sun Y, Yan X, Zeng X. Antioxidant activities of polysaccharides from Hyriopsis cumingii. Carbohydr Polym 2009. [DOI: 10.1016/j.carbpol.2009.03.018] [Citation(s) in RCA: 187] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Yan X, Tezel G, Wax MB, Edward DP. Matrix metalloproteinases and tumor necrosis factor alpha in glaucomatous optic nerve head. ARCHIVES OF OPHTHALMOLOGY (CHICAGO, ILL. : 1960) 2000; 118:666-73. [PMID: 10815159 DOI: 10.1001/archopht.118.5.666] [Citation(s) in RCA: 182] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
OBJECTIVE To study expression and location of matrix metalloproteinases (MMPs) and tumor necrosis factor alpha (TNF-alpha) in glaucomatous optic nerve heads, which are known to be secreted in response to a variety of neuronal injury. METHODS Four postmortem eyes from patients with primary open-angle glaucoma, 7 eyes from patients with normal-pressure glaucoma, and 4 eyes from age-matched normal donors were studied by immunohistochemistry. The sections of the optic nerve heads were examined after immunostaining with antibodies to MMPs (MMP-1, MMP-2, and MMP-3), TNF-alpha, or TNF-alpha receptor 1. RESULTS The intensity of the immunostaining and the number of stained cells for MMPs, TNF-alpha, or TNF-alpha receptor 1 were greater in the glaucomatous optic nerve heads, particularly in eyes with normal-pressure glaucoma compared with age-matched controls. Positive immunostaining was observed in all regions of the glaucomatous optic nerve heads, but most prominently in the postlaminar region. Immunostaining was observed mainly in glial cells and their processes around the axons and blood vessels and in pial septae. CONCLUSION There is increased immunostaining for MMPs, TNF-alpha and TNF-alpha receptor 1 in the glaucomatous optic nerve head, which suggests increased expression of these proteins in glaucoma and thereby implies a role in the tissue remodeling and degenerative changes seen in glaucomatous optic nerve heads. CLINICAL RELEVANCE The MMPs and TNF-alpha may be components of astroglial activation that occurs in glaucomatous optic nerve heads. The biological alterations in the expression of these proteins may play a role in the progression of glaucomatous optic neuropathy.
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Shi L, Huang H, Lu X, Yan X, Jiang X, Xu R, Wang S, Zhang C, Yuan X, Xu Z, Huang L, Fu JL, Li Y, Zhang Y, Yao WQ, Liu T, Song J, Sun L, Yang F, Zhang X, Zhang B, Shi M, Meng F, Song Y, Yu Y, Wen J, Li Q, Mao Q, Maeurer M, Zumla A, Yao C, Xie WF, Wang FS. Effect of human umbilical cord-derived mesenchymal stem cells on lung damage in severe COVID-19 patients: a randomized, double-blind, placebo-controlled phase 2 trial. Signal Transduct Target Ther 2021; 6:58. [PMID: 33568628 PMCID: PMC7873662 DOI: 10.1038/s41392-021-00488-5] [Citation(s) in RCA: 173] [Impact Index Per Article: 43.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2020] [Accepted: 01/15/2021] [Indexed: 12/15/2022] Open
Abstract
Treatment of severe Coronavirus Disease 2019 (COVID-19) is challenging. We performed a phase 2 trial to assess the efficacy and safety of human umbilical cord-mesenchymal stem cells (UC-MSCs) to treat severe COVID-19 patients with lung damage, based on our phase 1 data. In this randomized, double-blind, and placebo-controlled trial, we recruited 101 severe COVID-19 patients with lung damage. They were randomly assigned at a 2:1 ratio to receive either UC-MSCs (4 × 107 cells per infusion) or placebo on day 0, 3, and 6. The primary endpoint was an altered proportion of whole lung lesion volumes from baseline to day 28. Other imaging outcomes, 6-minute walk test (6-MWT), maximum vital capacity, diffusing capacity, and adverse events were recorded and analyzed. In all, 100 COVID-19 patients were finally received either UC-MSCs (n = 65) or placebo (n = 35). UC-MSCs administration exerted numerical improvement in whole lung lesion volume from baseline to day 28 compared with the placebo (the median difference was -13.31%, 95% CI -29.14%, 2.13%, P = 0.080). UC-MSCs significantly reduced the proportions of solid component lesion volume compared with the placebo (median difference: -15.45%; 95% CI -30.82%, -0.39%; P = 0.043). The 6-MWT showed an increased distance in patients treated with UC-MSCs (difference: 27.00 m; 95% CI 0.00, 57.00; P = 0.057). The incidence of adverse events was similar in the two groups. These results suggest that UC-MSCs treatment is a safe and potentially effective therapeutic approach for COVID-19 patients with lung damage. A phase 3 trial is required to evaluate effects on reducing mortality and preventing long-term pulmonary disability. (Funded by The National Key R&D Program of China and others. ClinicalTrials.gov number, NCT04288102.
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Clinical Trial, Phase II |
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Yan XY, Tong XL, Zhang YF, Han XD, Wang YY, Jin GQ, Qin Y, Guo XY. Cuprous oxide nanoparticles dispersed on reduced graphene oxide as an efficient electrocatalyst for oxygen reduction reaction. Chem Commun (Camb) 2012; 48:1892-4. [DOI: 10.1039/c2cc17537a] [Citation(s) in RCA: 170] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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Shimon I, Yan X, Taylor JE, Weiss MH, Culler MD, Melmed S. Somatostatin receptor (SSTR) subtype-selective analogues differentially suppress in vitro growth hormone and prolactin in human pituitary adenomas. Novel potential therapy for functional pituitary tumors. J Clin Invest 1997; 100:2386-92. [PMID: 9410919 PMCID: PMC508437 DOI: 10.1172/jci119779] [Citation(s) in RCA: 156] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Previously, we have shown somatostatin receptor (SSTR) subtype-specific regulation of growth hormone (GH), thyroid-stimulating hormone, and prolactin (PRL) secretion in human fetal pituitary cultures, where GH and thyroid-stimulating hormone are mediated by both SSTR2 and SSTR5, whereas SSTR2 preferentially mediates PRL secretion. We now tested SSTR subtype-selective analogues in primary human GH- and PRL-secreting pituitary adenoma cultures. Analogue affinities determined by membrane radioligand binding in cells stably expressing human SSTR forms were either SSTR2 or SSTR5-selective. Analogues preferential either for SSTR2, including octreotide, lanreotide, and novel compounds with improved affinity for SSTR2, or new SSTR5-selective compounds suppressed GH in tumor cell cultures (up to 44% of control; P < 0.0005). However, novel analogues from both groups were 30-40% more potent than octreotide and lanreotide in suppressing GH (P < 0.05). Heterologous analogue combinations containing both SSTR2- and SSTR5-selective compounds were more potent in decreasing GH than analogues used alone (P < 0.05), or than combinations of compounds specific for the same receptor subtype (P < 0.005). In contrast, SSTR2-selective analogues did not suppress PRL release from six cultured prolactinomas studied. However, new SSTR5-selective analogues suppressed in vitro PRL secretion (30-40%; P < 0.05) in four of six prolactinomas. These results suggest that both SSTR2 and SSTR5 are involved in GH regulation in somatotroph adenoma cells, whereas SSTR5 exclusively regulates PRL secretion from prolactinoma cells. Thus, somatostatin analogues with improved selective binding affinity for these receptor subtypes may be effective in the treatment of either GH- or PRL-secreting adenomas.
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Barb CR, Yan X, Azain MJ, Kraeling RR, Rampacek GB, Ramsay TG. Recombinant porcine leptin reduces feed intake and stimulates growth hormone secretion in swine. Domest Anim Endocrinol 1998; 15:77-86. [PMID: 9437587 DOI: 10.1016/s0739-7240(97)00064-7] [Citation(s) in RCA: 138] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Two experiments (EXP) were conducted to test the hypothesis that porcine leptin affects GH, insulin-like growth factor-I (IGF-I), insulin, thyroxine (T4) secretion, and feed intake. In EXP I, prepuberal gilts received intracerebroventricular (i.c.v.) leptin injections. Blood was collected every 15 min for 4 hr before and 3 hr after i.c.v. injections of 0.9% saline (S; n = 3), 10 micrograms (n = 4), 50 micrograms (n = 4), or 100 micrograms (n = 4) of leptin in S. Pigs were fed each day at 0800 and 1700 hr over a 2-wk period before the EXP. On the day of the EXP, pigs were fed at 0800 hr and blood sampling started at 0900 h. After the last sample was collected, feeders were placed in all pens. Feed intake was monitored at 4, 20, and 44 hr after feed presentation. In EXP II, pituitary cells from prepuberal gilts were studied in primary culture to determine if leptin affects GH secretion at the level of the pituitary. On Day 4 of culture, 10(5) cells/well were challenged with 10(-12), 10(-10), 10(-8), or 10(-6) M [Ala15]-h growth hormone-releasing factor-(1-29)NH2 (GRF), 10(-14), 10(-13), 10(-12), 10(-11), 10(-10), 10(-9), 10(-8), 10(-7), or 10(-6) M leptin individually or in combinations with 10(-8) and 10(-6) M GRF. Secreted GH was measured at 4 hr after treatment. In EXP I, before injection, serum GH concentrations were similar. Serum GH concentrations increased (P < 0.01) after injection of 10 micrograms (21 +/- 1 ng/ml), 50 micrograms (9 +/- 1 ng/ml), and 100 micrograms (13 +/- 1 ng/ml) of leptin compared with S (1 +/- 2 ng/ml) treated pigs. The GH response to leptin was greater (P < 0.001) in 10 micrograms than 50 or 100 micrograms leptin-treated pigs. By 20 hr the 10, 50, and 100 micrograms doses of leptin reduced feed intake by 53% (P < 0.08), 76%, and 90% (P < 0.05), respectively, compared with S pigs. Serum IGF-1, insulin, T4, glucose, and free fatty acids were unaffected by leptin treatment. In EXP II, relative to control (31 +/- 2 ng/well), 10(-10), 10(-8), and 10(-6) M GRF increased (P < 0.01) GH secretion by 131%, 156%, and 170%, respectively. Only 10(-6) M and 10(-7) M leptin increased (P < 0.01) GH secretion. Addition of 10(-11) and 10(-9) M leptin in combination with 10(-6) M GRF or 10(-11) M leptin in combination with 10(-8) M GRF-suppressed (P < 0.05) GH secretion. These results indicate that leptin modulates GH secretion and, as shown in other species, leptin suppressed feed intake in the pig.
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Yan X, Olson NH, Van Etten JL, Bergoin M, Rossmann MG, Baker TS. Structure and assembly of large lipid-containing dsDNA viruses. NATURE STRUCTURAL BIOLOGY 2000; 7:101-3. [PMID: 10655609 PMCID: PMC4167659 DOI: 10.1038/72360] [Citation(s) in RCA: 127] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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Zhu HH, Wu DP, Du X, Zhang X, Liu L, Ma J, Shao ZH, Ren HY, Hu JD, Xu KL, Wang JW, Song YP, Fang MY, Li J, Yan XY, Huang XJ. Oral arsenic plus retinoic acid versus intravenous arsenic plus retinoic acid for non-high-risk acute promyelocytic leukaemia: a non-inferiority, randomised phase 3 trial. Lancet Oncol 2018; 19:871-879. [PMID: 29884593 DOI: 10.1016/s1470-2045(18)30295-x] [Citation(s) in RCA: 117] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Revised: 03/31/2018] [Accepted: 04/11/2018] [Indexed: 01/11/2023]
Abstract
BACKGROUND Intravenous arsenic trioxide plus all-trans retinoic acid (ATRA) without chemotherapy is the standard of care for non-high-risk acute promyelocytic leukaemia (white blood cell count ≤10 × 109 per L), resulting in cure in more than 95% of cases. However, a pilot study of treatment with oral arsenic realgar-Indigo naturalis formula (RIF) plus ATRA without chemotherapy, which has a more convenient route of administration than the standard intravenous regimen, showed high efficacy. In this study, we compare an oral RIF plus ATRA treatment regimen with the standard intravenous arsenic trioxide plus ATRA treatment regimen in patients with non-high-risk acute promyelocytic leukaemia. METHODS We did a multicentre, non-inferiority, open-label, randomised, controlled phase 3 trial at 14 centres in China. Patients aged 18-70 years with newly diagnosed (within 7 days) non-high-risk acute promyelocytic leukaemia, and a WHO performance status of 2 or less were eligible. Patients were randomly assigned (2:1) to receive treatment with RIF-ATRA or arsenic trioxide-ATRA as the induction and consolidation therapy. Randomisation was done centrally with permuted blocks and stratification according to trial centre and was implemented through an interactive web response system. RIF (60 mg/kg bodyweight daily in an oral divided dose) or arsenic trioxide (0·15 mg/kg daily in an intravenous dose) and ATRA (25 mg/m2 daily in an oral divided dose) were used until complete remission was achieved. The home-based consolidation therapy was RIF (60 mg/kg daily in an oral divided dose) or intravenous arsenic trioxide (0·15 mg/kg daily in an intravenous dose) in a 4-week on 4-week off regimen for four cycles and ATRA (25 mg/m2 daily in an oral divided dose) in a 2-week on 2-week off regimen for seven cycles. Patients and treating physicians were not masked to treatment allocation. The primary outcome was event-free survival at 2 years. A non-inferiority margin of -10% was used to assess non-inferiority. Primary analyses were done in a modified intention-to-treat population of all patients who received at least one dose of their assigned treatment and the per-protocol population. This study was registered with the Chinese Clinical Trial Registry (ChiCTR-TRC-13004054), and the trial is complete. FINDINGS Between Feb 13, 2014, and Aug 31, 2015, 109 patients were enrolled and assigned to RIF-ATRA (n=72) or arsenic trioxide-ATRA (n=37). Three patients in the RIF-ATRA and one in the arsenic trioxide-ATRA did not receive their assigned treatment. After a median follow-up of 32 months (IQR 27-36), 67 (97%) of 69 patients in the RIF-ATRA group and 34 (94%) of 36 in the arsenic trioxide-ATRA group had achieved 2-year event-free survival in the modified intention-to-treat population. The percentage difference in event-free survival was 2·7% (95% CI, -5·8 to 11·1). The lower limit of the 95% CI for the difference in event-free survival was greater than the -10% non-inferiority margin, confirming non-inferiority (p=0·0017). Non-inferiority was also confirmed in the per-protocol population. During induction therapy, grade 3-4 hepatic toxic effects (ie, increased liver aspartate aminotransferase or alanine transaminase concentrations) were reported in six (9%) of 69 patients in the RIF-ATRA group versus five (14%) of 36 patients in the arsenic trioxide-ATRA group; grade 3-4 infection was reported in 15 (23%) of 64 versus 15 (42%) of 36 patients. Two patients in the arsenic trioxide-ATRA group died during induction therapy (one from haemorrhage and one from thrombocytopenia). INTERPRETATION Oral RIF plus ATRA is not inferior to intravenous arsenic trioxide plus ATRA for the treatment of patients with non-high-risk acute promyelocytic leukaemia. This study suggests that a completely oral, chemotherapy-free model might be an alternative to the standard intravenous treatment for patients with non-high-risk acute promyelocytic leukaemia. FUNDING Foundation for innovative research group of the National Natural Science Foundation of China, the Beijing Municipal Science and Technology Commission, the National Key R&D Program of China, and the National Natural Science Foundation of China.
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Research Support, Non-U.S. Gov't |
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Burke TR, Ye B, Yan X, Wang S, Jia Z, Chen L, Zhang ZY, Barford D. Small molecule interactions with protein-tyrosine phosphatase PTP1B and their use in inhibitor design. Biochemistry 1996; 35:15989-96. [PMID: 8973169 DOI: 10.1021/bi961256d] [Citation(s) in RCA: 113] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
We have previously shown that a small peptide bearing the hydrolytically stable phosphotyrosyl (pTyr) mimetic, (difluorophosphonomethyl) phenylalanine (F2Pmp), is an extremely potent inhibitor of PTP1B, with an IC50 value of 100 nM [Burke, T. R., Kole, H. K., & Roller, P. P. (1994) Biochem. Biophys. Res. Commun. 204, 129-134]. We further demonstrated that removal of the peptide portion and incorporation of the difluorophosphonomethyl moiety onto a naphthalene ring system, but not a phenyl ring system, resulted in good inhibitory potency [Kole, H. K., Smyth, M. S., Russ, P. L., & Burke, T. R., Jr. (1995) Biochem, J. 311, 1025-1031]. In order to understand the structural basis for this inhibition, and to aid in the design of further analogs, we solved the X-ray structure of [1, 1-difluoro-1-(2-naphthalenyl)-methyl]phosphonic acid (6) complexed within the catalytic site of PTP1B, solved to 2.3 A resolution. In addition to showing the manner in which the phosphonate group is held within the catalytic site, the X-ray structure also revealed extensive hydrophobic interactions with the naphthalene ring system, beyond that possible with an analog bearing a single phenyl ring. It is further evident that, of the two fluorine atoms, the pro-R alpha-fluorine interacts with the enzyme to a significantly greater degree than the pro-S alpha-fluorine, forming a hydrogen bond to Phe 182. On the basis of a computer-assisted molecular modeling analysis, it was determined that addition of a hydroxyl to the naphthyl 4-position, giving [1, 1-difluoro-1-[2-(4-hydroxynaphthalenyl)] methyl]phosphonic acid (8), could potentially replace a water molecule situated in the PTP1B-6 complex, thereby allowing new hydrogen-bonding interactions with Lys 120 and Tyr 46. Compound 8 was therefore prepared and found to exhibit a doubling of affinity (Ki = 94 microM) relative to parent unsubstituted 6 (Ki = 179 microM), supporting, in principle, the development of high-affinity ligands based on molecular modeling analysis of the enzyme-bound parent.
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Wang R, Wu C, Zhao Y, Yan X, Ma X, Wu M, Liu W, Gu Z, Zhao J, He J. Health related quality of life measured by SF-36: a population-based study in Shanghai, China. BMC Public Health 2008; 8:292. [PMID: 18710578 PMCID: PMC2527564 DOI: 10.1186/1471-2458-8-292] [Citation(s) in RCA: 112] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2008] [Accepted: 08/19/2008] [Indexed: 01/22/2023] Open
Abstract
BACKGROUND Health related quality of life (HRQL) is a research topic that has attracted increasing interests around the world over the past two decades. The 36-item Short Form (SF-36) is a commonly used instrument for measuring HRQL. However, the information on Chinese adults' quality of life is limited. This paper reports on the feasibility of using the Mandarin version of SF-36 to evaluate HRQL in the population of Shanghai, China. METHODS A total of 1034 subjects were randomly sampled using a stratified multiple-stage sampling method in Shanghai. Demographic information was collected, and SF-36 was used to measure HRQL. RESULTS Internal reliability coefficients were greater than 0.7 in six of the eight SF-36 dimensions, except social function and mental health. Intraclass correlation coefficients ranged from 0.689 to 0.972. Split-half reliability coefficients were higher than 0.9 in five SF-36 dimensions. Validity was assessed by factor analysis and correlation analysis. Our results were basically in accordance with the theoretical construction of SF-36. The average scores of most SF-36 dimensions were higher than 80. The primary influencing risk factors of HRQL included chronic diseases, age, frequency of activities, and geographical region, which were identified using multivariate stepwise regression. CONCLUSION Overall, HRQL in the population of Shanghai is quite good. The Mandarin version of SF-36 is a valid and reliable tool for assessing HRQL.
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Validation Study |
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Li J, Yang L, Song L, Xiong H, Wang L, Yan X, Yuan J, Wu J, Li M. Astrocyte elevated gene-1 is a proliferation promoter in breast cancer via suppressing transcriptional factor FOXO1. Oncogene 2009; 28:3188-96. [PMID: 19633686 DOI: 10.1038/onc.2009.171] [Citation(s) in RCA: 105] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
We have previously reported that astrocyte elevated gene-1 (AEG-1) was upregulated in human breast cancer. However, the biological function of AEG-1 in the development and progression of breast cancer remains to be clarified. In this study, we examined the effect of AEG-1 on cell proliferation and found that AEG-1 upregulation was significantly linked to increased Ki67 (P<0.001). Ectopic expression of AEG-1 in MCF-7 and MDA-MB-435 breast cancer cells dramatically enhanced cell proliferation and their ability of anchorage-independent growth, whereas silencing endogenous AEG-1 with shRNAs inhibited cell proliferation and colony-forming ability of the cells on soft agar. Furthermore, these proliferative effects were significantly associated with decreases of p27Kip1 and p21Cip1 two key cell-cycle inhibitors. Moreover, we further demonstrated that AEG-1 could downregulate the transcriptional activity of FOXO1 by inducing its phosphorylation through the PI3K/Akt signaling pathway. These observations were further confirmed in clinical human primary breast cancer specimens, in which high-level expression of AEG-1 was inversely correlated with the expression of FOXO1. Taken together, our results provide the first demonstration of a novel mechanism by which AEG-1 induces proliferation of breast cancer cell, and our findings suggest that AEG-1 might play an important role in tumorigenesis of breast cancer.
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Research Support, Non-U.S. Gov't |
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Wang W, Zhao Z, Yang F, Wang H, Wu F, Liang T, Yan X, Li J, Lan Q, Wang J, Zhao J. An immune-related lncRNA signature for patients with anaplastic gliomas. J Neurooncol 2017; 136:263-271. [PMID: 29170907 DOI: 10.1007/s11060-017-2667-6] [Citation(s) in RCA: 102] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Accepted: 11/11/2017] [Indexed: 12/26/2022]
Abstract
We investigated immune-related long non-coding RNAs (lncRNAs) that may be exploited as potential therapeutic targets in anaplastic gliomas. We obtained 572 lncRNAs and 317 immune genes from the Chinese Glioma Genome Atlas microarray and constructed immune-related lncRNAs co-expression networks to identify immune-related lncRNAs. Two additional datasets (GSE16011, REMBRANDT) were used for validation. Gene set enrichment analysis and principal component analysis were used for functional annotation. Immune-lncRNAs co-expression networks were constructed. Nine immune-related lncRNAs (SNHG8, PGM5-AS1, ST20-AS1, LINC00937, AGAP2-AS1, MIR155HG, TUG1, MAPKAPK5-AS1, and HCG18) signature was identified in patients with anaplastic gliomas. Patients in the low-risk group showed longer overall survival (OS) and progression-free survival than those in the high-risk group (P < 0.0001; P < 0.0001). Additionally, patients in the high-risk group displayed no-deletion of chromosomal arms 1p and/or 19q, isocitrate dehydrogenase wild-type, classical and mesenchymal TCGA subtype, G3 CGGA subtype, and lower Karnofsky performance score (KPS). Moreover, the signature was an independent factor and was significantly associated with the OS (P = 0.000, hazard ratio (HR) = 1.434). These findings were further validated in two additional datasets (GSE16011, REMBRANDT). Low-risk and high-risk groups displayed different immune status based on principal components analysis. Our results showed that the nine immune-related lncRNAs signature has prognostic value for anaplastic gliomas.
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Journal Article |
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Liao H, Rubio G, Yan X, Cao A, Brown KM, Lynch JP. Effect of phosphorus availability on basal root shallowness in common bean. PLANT AND SOIL 2001. [PMID: 11729851 DOI: 10.1023/a:1010381919003] [Citation(s) in RCA: 101] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Root gravitropism may be an important element of plant response to phosphorus availability because it determines root foraging in fertile topsoil horizons, and thereby phosphorus acquisition. In this study we seek to test this hypothesis in both two dimensional paper growth pouch and three-dimensional solid media of sand and soil cultures. Five common bean ( Phaseolus vulgaris L.) genotypes with contrasting adaptation to low phosphorus availability were evaluated in growth pouches over 6 days of growth, and in sand culture and soil culture over 4 weeks of growth. In all three media, phosphorus availability regulated the gravitropic response of basal roots in a genotype-dependent manner. In pouches, sand, and soil, the phosphorus-inefficient genotype DOR 364 had deeper roots with phosphorus stress, whereas the phosphorus-efficient genotype G19833 responded to phosphorus stress by producing shallower roots. Genotypes were most responsive to phosphorus stress in sand culture, where relative root allocation to the 0-3- and 3-6-cm horizons increased 50% with phosphorus stress, and varied 300% (3-6 cm) to 500% (0-3 cm) among genotypes. Our results indicate that (1) phosphorus availability regulates root gravitropic growth in both paper and solid media, (2) responses observed in young seedlings continue throughout vegetative growth, (3) the response of root gravitropism to phosphorus availability varies among genotypes, and (4) genotypic adaptation to low phosphorus availability is correlated with the ability to allocate roots to shallow soil horizons under phosphorus stress.
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Comparative Study |
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Bi Z, Zhang W, Yan X. Anti-inflammatory and immunoregulatory effects of icariin and icaritin. Biomed Pharmacother 2022; 151:113180. [PMID: 35676785 DOI: 10.1016/j.biopha.2022.113180] [Citation(s) in RCA: 98] [Impact Index Per Article: 32.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Revised: 05/18/2022] [Accepted: 05/22/2022] [Indexed: 11/02/2022] Open
Abstract
Inflammation and immunity dysregulation have received widespread attention in recent years due to their occurrence in the pathophysiology of many conditions. In this regard, several pharmacological studies have been conducted aiming to evaluate the potential anti-inflammatory and immunomodulatory effects of phytochemicals. Epimedium, a traditional Chinese medicine, is often used as a tonic, aphrodisiac, and anti-rheumatic agent. Icariin (ICA) is the main active ingredient of Epimedium and is, once ingested, mainly metabolized into Icaritin (ICT). Data from in vitro and in vivo studies suggested that ICA and its metabolite (ICT) regulated the functions and activation of immune cells, modulated the release of inflammatory factors, and restored aberrant signaling pathways. ICA and ICT were also involved in anti-inflammatory and immune responses in several diseases, including multiple sclerosis, asthma, atherosclerosis, lupus nephritis, inflammatory bowel diseases, rheumatoid arthritis, and cancer. Yet, data showed that ICA and ICT exhibited similar but not identical pharmacokinetic properties. Therefore, based on their higher solubility and bioavailability, as well as trends indicating that single-ingredient compounds offer broader and safer therapeutic capabilities, ICA and ICT delivery systems and treatment represent interesting avenues with promising clinical applications. In this study, we reviewed the anti-inflammatory and immunomodulatory mechanisms, as well as the pharmacokinetic properties of ICA and its metabolite ICT.
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Review |
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Li Z, Zou D, Ma X, Chen J, Shi X, Gong Y, Man X, Gao L, Zhao Y, Wang R, Yan X, Dent J, Sung JJ, Wernersson B, Johansson S, Liu W, He J. Epidemiology of peptic ulcer disease: endoscopic results of the systematic investigation of gastrointestinal disease in China. Am J Gastroenterol 2010; 105:2570-7. [PMID: 20736940 DOI: 10.1038/ajg.2010.324] [Citation(s) in RCA: 97] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
OBJECTIVES Complications of peptic ulcer disease (PUD) are common in China. Population-based estimates of the prevalence of PUD are needed to quantify and characterize the population at risk of these complications. METHODS As part of a large epidemiological study, 3,600 randomly selected residents of Shanghai (aged 18-80 years) were asked to undergo endoscopy and to provide blood samples for Helicobacter pylori serology. All participants also completed a general information questionnaire and Chinese versions of the reflux disease questionnaire (RDQ) and Rome II questionnaire. Associations between PUD and other factors were analyzed using a multiple logistic regression model. RESULTS In total, 3,153 individuals (87.6%) completed the survey. All underwent blood tests, and 1,030 patients (32.7%) agreed to undergo endoscopy. Results from 1,022 patients were suitable for analysis. In all, 176 participants (17.2%) had PUD (62 with gastric ulcer; 136 with duodenal ulcer). The prevalence of H. pylori infection was 73.3% in the total population and 92.6% among those with PUD. H. pylori infection was associated with the presence of PUD (odds ratio (OR), 6.77; 95% confidence interval (CI), 2.85-16.10). The majority (72.2%) of individuals with PUD had none of the upper gastrointestinal symptoms assessed by the RDQ. PUD was not significantly associated with symptom-defined gastroesophageal reflux disease (GERD) (OR, 0.80; 95% CI, 0.32-2.03), reflux esophagitis (OR, 1.46; 95% CI, 0.76-2.79) or dyspepsia (OR, 1.69; 95% CI, 0.94-3.04). CONCLUSIONS The prevalence of endoscopically confirmed PUD in this Shanghai population (17.2%) is substantially higher than in Western populations (4.1%). The majority of individuals with PUD were asymptomatic.
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Liu FH, Wang SB, Zhang JS, Zhang J, Yan X, Zhou HK, Zhao GP, Zhou ZH. The structure of the bacterial and archaeal community in a biogas digester as revealed by denaturing gradient gel electrophoresis and 16S rDNA sequencing analysis. J Appl Microbiol 2009; 106:952-66. [PMID: 19187154 DOI: 10.1111/j.1365-2672.2008.04064.x] [Citation(s) in RCA: 92] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
AIMS To identify the bacterial and archaeal composition in a mesophilic biogas digester treating pig manure and to compare the consistency of two 16S rDNA-based methods to investigate the microbial structure. METHODS AND RESULTS Sixty-nine bacterial operational taxonomic units (OTU) and 25 archaeal OTU were identified by sequencing two 16S rDNA clone libraries. Most bacterial OTU were identified as phyla of Firmicutes (47.2% of total clones), Bacteroides (35.4%) and Spirochaetes (13.2%). Methanoculleus bourgensis (29.0%), Methanosarcina barkeri (27.4%) and Methanospirillum hungatei (10.8%) were the dominant methanogens. Only 9% of bacterial and 20% of archaeal OTU matched cultured isolates at a similarity index of >or=97%. About 78% of the dominant bacterial (with abundance >3%) and 83% of archaeal OTU were recovered from the denaturing gradient gel electrophoresis (DGGE) bands of V3 regions in 16S rDNAs. CONCLUSIONS In the digester, most bacterial and archaeal species were uncultured; bacteria belonging to Firmicutes, Bacteroides and Spirochaetes seem to take charge of cellulolysis, proteolysis, acidogenesis, sulfur-reducing and homoacetogenesis; the most methanogens were typical hydrogenotrophic or hydrogenotrophic/aceticlastic; DGGE profiles reflected the dominant microbiota. SIGNIFICANCE AND IMPACT OF THE STUDY This study gave a first insight of the overall microbial structure in a rural biogas digester and also indicated DGGE was useful in displaying its dominant microbiota.
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Research Support, Non-U.S. Gov't |
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92 |
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Liu D, Yang R, Yan X, McAdoo DJ. Hydroxyl radicals generated in vivo kill neurons in the rat spinal cord: electrophysiological, histological, and neurochemical results. J Neurochem 1994; 62:37-44. [PMID: 8263539 DOI: 10.1046/j.1471-4159.1994.62010037.x] [Citation(s) in RCA: 92] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
We have used microdialysis to establish an experimental model to characterize mechanisms whereby released substances cause secondary damage in spinal cord injury. We use this model here to characterize damaging effects of the hydroxyl radical (OH.) in vivo in the spinal cord. OH. was generated in vivo by pumping H2O2 and FeCl2/EDTA through parallel microdialysis fibers inserted into the spinal cord. These agents mixed in the tissue to produce OH. by Fenton's reaction. Two types of control experiments were also conducted, one administering only 5 mM H2O2 and the other only 0.5 mM FeCl2/0.82 mM EDTA. During administration of these chemicals, electrical conduction was recorded as one test for deterioration. OH. blocked conduction completely in 2.5-5 h and Fe2+/EDTA partly blocked conduction, but H2O2 alone did not cause detectable blockage. Histological examination supported the hypothesis that neurons were killed by OH., as Fe2+/EDTA and H2O2 alone did not destroy significant numbers of neurons. OH., H2O2, and Fe2+ all caused gradual increases in extracellular amino acid levels. These results are consistent with Fe(2+)-catalyzed free radical generation playing a role in tissue damage upon spinal cord injury.
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Wang S, Milne GW, Yan X, Posey IJ, Nicklaus MC, Graham L, Rice WG. Discovery of novel, non-peptide HIV-1 protease inhibitors by pharmacophore searching. J Med Chem 1996; 39:2047-54. [PMID: 8642563 DOI: 10.1021/jm950874+] [Citation(s) in RCA: 92] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Fifteen novel non-peptide HIV-1 protease inhibitors were identified by flexible 3D database pharmacophore searching of the NCI DIS 3D database. The pharmacophore query used in the search was derived directly from the X-ray determined structures of protease/inhibitor complexes. These 15 inhibitors, belonging to nine different chemical classes, are promising leads for further development. The two best inhibitors found, NSC 32180, a "dimer" of 4-hydroxycoumarin, and NSC 117027, a "tetramer" of 2-hydroxy quinone, had ID50 values of 0.32 and 0.75 microM for HIV-1 protease inhibition, respectively, and two other inhibitors had ID50 values close to 1 microM. Among the potent inhibitors, NSC 158393 not only demonstrated activity against HIV-1 protease (ID50 1.7 microM) but also exhibited promising antiviral activity in HIV-1-infected CEM-SS cells (EC50 = 11.5 microM). Validation of the pharmacophore used in the search was accomplished by conformational analysis. The binding modes of the most potent inhibitor found in our studies, NSC 32180, were predicted employing docking and molecular dynamics techniques.
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Yan X, Nagata T, Fan X. Antioxidative activities in some common seaweeds. PLANT FOODS FOR HUMAN NUTRITION (DORDRECHT, NETHERLANDS) 1998; 52:253-262. [PMID: 9950086 DOI: 10.1023/a:1008007014659] [Citation(s) in RCA: 89] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Dietary antioxidants from plants are believed to help prevent aging and other diseases through radical scavenging activity. Free radical scavenging activities by 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay and deoxyribose assay were ascertained among 27 species of common seaweeds using a sequential extraction method. The results indicated that, DPPH scavenging activity existed in 15 species; Gelidium amansii, Gloiosiphonia capillaris, Polysiphonia urceolata, Sargassum kjellmanianum, Desmarestia viridis, and Rhodomela teres showed the strongest activities. On the other hand, the deoxyribose results showed that almost all the seaweed species had good ability to scavenge hydroxyl radicals. The most active species were Rhodomela teres and Chorda filum.
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Rohrbach S, Yan X, Weinberg EO, Hasan F, Bartunek J, Marchionni MA, Lorell BH. Neuregulin in cardiac hypertrophy in rats with aortic stenosis. Differential expression of erbB2 and erbB4 receptors. Circulation 1999; 100:407-12. [PMID: 10421602 DOI: 10.1161/01.cir.100.4.407] [Citation(s) in RCA: 86] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
BACKGROUND Neuregulins are a family of peptide growth factors that promote cell growth and viability. The potential role of neuregulin-erbB signaling in hypertrophic growth and later failure in the adult heart in vivo is not known. METHODS AND RESULTS We used ribonuclease protection assays to quantify mRNA levels of neuregulin, erbB2, and erbB4 in left ventricular (LV) tissue and myocytes of normal rats and rats with aortic stenosis with pressure-overload hypertrophy 6 and 22 weeks after banding. At both stages of hypertrophy, Northern blot analyses of mRNA from LV myocytes showed upregulation of atrial natriuretic peptide, a molecular marker of hypertrophy (P<0.05). LV tissue neuregulin message levels were similar in animals with aortic stenosis compared with controls (P=NS) and were not detectable in myocytes. LV erbB2 and erbB4 message levels in LV tissue and myocytes were maintained during early compensatory hypertrophy in 6-week aortic stenosis animals compared with age-matched controls; in contrast, erbB2 and erbB4 message levels were depressed in 22-week aortic stenosis animals at the stage of early failure (both P<0.01 vs age-matched controls). Immunoblotting of erbB2 and erbB4 also showed normal protein levels in 6-week aortic stenosis animals compared with controls; however, erbB2 and erbB4 protein levels were depressed in 22-week aortic stenosis animals (48% decrease in erbB2, P<0.05, and 43% decrease in erbB4, P<0.01) relative to age-matched controls. CONCLUSIONS The neuregulin receptors erbB2 and erbB4 are downregulated at both the message and protein levels at the stage of early failure in animals with chronic hypertrophy secondary to aortic stenosis. These data suggest a role for disabled erbB receptor signaling in the transition from compensatory hypertrophy to failure.
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Su J, Hu C, Yan X, Jin Y, Chen Z, Guan Q, Wang Y, Zhong D, Jansson C, Wang F, Schnürer A, Sun C. Expression of barley SUSIBA2 transcription factor yields high-starch low-methane rice. Nature 2015. [PMID: 26200336 DOI: 10.1038/nature14673] [Citation(s) in RCA: 85] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Atmospheric methane is the second most important greenhouse gas after carbon dioxide, and is responsible for about 20% of the global warming effect since pre-industrial times. Rice paddies are the largest anthropogenic methane source and produce 7-17% of atmospheric methane. Warm waterlogged soil and exuded nutrients from rice roots provide ideal conditions for methanogenesis in paddies with annual methane emissions of 25-100-million tonnes. This scenario will be exacerbated by an expansion in rice cultivation needed to meet the escalating demand for food in the coming decades. There is an urgent need to establish sustainable technologies for increasing rice production while reducing methane fluxes from rice paddies. However, ongoing efforts for methane mitigation in rice paddies are mainly based on farming practices and measures that are difficult to implement. Despite proposed strategies to increase rice productivity and reduce methane emissions, no high-starch low-methane-emission rice has been developed. Here we show that the addition of a single transcription factor gene, barley SUSIBA2 (refs 7, 8), conferred a shift of carbon flux to SUSIBA2 rice, favouring the allocation of photosynthates to aboveground biomass over allocation to roots. The altered allocation resulted in an increased biomass and starch content in the seeds and stems, and suppressed methanogenesis, possibly through a reduction in root exudates. Three-year field trials in China demonstrated that the cultivation of SUSIBA2 rice was associated with a significant reduction in methane emissions and a decrease in rhizospheric methanogen levels. SUSIBA2 rice offers a sustainable means of providing increased starch content for food production while reducing greenhouse gas emissions from rice cultivation. Approaches to increase rice productivity and reduce methane emissions as seen in SUSIBA2 rice may be particularly beneficial in a future climate with rising temperatures resulting in increased methane emissions from paddies.
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Research Support, U.S. Gov't, Non-P.H.S. |
10 |
85 |