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Kim C, Christophi CA, Goldberg RB, Perreault L, Dabelea D, Marcovina SM, Pi-Sunyer X, Barrett-Connor E. Adiponectin, C-reactive protein, fibrinogen and tissue plasminogen activator antigen levels among glucose-intolerant women with and without histories of gestational diabetes. Diabet Med 2016; 33:32-8. [PMID: 25970741 PMCID: PMC4644121 DOI: 10.1111/dme.12799] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 05/08/2015] [Indexed: 12/24/2022]
Abstract
AIM To examine concentrations of biomarkers (adiponectin, C-reactive protein, fibrinogen and tissue plasminogen-activator antigen) associated with glucose homeostasis and diabetes risk by history of gestational diabetes (GDM). METHODS We conducted a secondary analysis of the Diabetes Prevention Program, a randomized trial of lifestyle intervention or metformin for diabetes prevention. At baseline, participants were overweight and had impaired glucose tolerance. Biomarkers at baseline and 1 year after enrolment were compared between parous women with (n = 350) and without histories of GDM (n = 1466). Cox proportional hazard models evaluated whether history of GDM was associated with diabetes risk, after adjustment for baseline biomarker levels as well as for change in biomarker levels, demographic factors and anthropometrics. RESULTS At baseline, women with histories of GDM had lower adiponectin (7.5 μg/ml vs. 8.7 μg/ml; p < 0.0001) and greater log C-reactive protein (-0.90 mg/l vs. -0.78 mg/l, p = 0.04) levels than women without histories of GDM, but these associations did not persist after adjustment for demographic factors. Fibrinogen and tissue plasminogen-activator antigen were similar between women with and without histories of GDM. Women with and without histories of GDM had a similar pattern of changes in biomarkers within randomization arm. Adjustment for age, race/ethnicity, baseline weight, change in weight, baseline biomarker level and change in biomarker level did not significantly alter the association between history of GDM, and diabetes risk. CONCLUSIONS Among women with impaired glucose tolerance, biomarkers in women with and without histories of GDM are similar and respond similarly to lifestyle changes and metformin. Adjustment for biomarker levels did not explain the higher risk of diabetes observed in women with histories of GDM.
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Affiliation(s)
- C Kim
- Departments of Medicine and Obstetrics and Gynecology, University of Michigan, Ann Arbor, MI, USA
| | - C A Christophi
- Biostatistics Center, George Washington University, Rockville, MD, USA
| | - R B Goldberg
- Department of Medicine, University of Miami, Miami, FL, USA
| | - L Perreault
- Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - D Dabelea
- Department of Preventive Medicine and Biometrics, Colorado School of Public Health, Aurora, CO, USA
| | - S M Marcovina
- Department of Medicine, University of Washington, Seattle, WA, USA
| | - X Pi-Sunyer
- Division of Endocrinology, Columbia University Medical Center, New York City, NY, USA
| | - E Barrett-Connor
- Department of Family and Preventive Medicine, University of California, San Diego, CA, USA
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Mather KJ, Kim C, Christophi CA, Aroda VR, Knowler WC, Edelstein SE, Florez JC, Labrie F, Kahn SE, Goldberg RB, Barrett-Connor E. Steroid Sex Hormones, Sex Hormone-Binding Globulin, and Diabetes Incidence in the Diabetes Prevention Program. J Clin Endocrinol Metab 2015; 100. [PMID: 26200237 PMCID: PMC4596040 DOI: 10.1210/jc.2015-2328] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CONTEXT Steroid sex hormones and SHBG may modify metabolism and diabetes risk, with implications for sex-specific diabetes risk and effects of prevention interventions. OBJECTIVE This study aimed to evaluate the relationships of steroid sex hormones, SHBG and SHBG single-nucleotide polymorphisms (SNPs) with diabetes risk factors and with progression to diabetes in the Diabetes Prevention Program (DPP). DESIGN AND SETTING This was a secondary analysis of a multicenter randomized clinical trial involving 27 U.S. academic institutions. PARTICIPANTS The study included 2898 DPP participants: 969 men, 948 premenopausal women not taking exogenous sex hormones, 550 postmenopausal women not taking exogenous sex hormones, and 431 postmenopausal women taking exogenous sex hormones. INTERVENTIONS Participants were randomized to receive intensive lifestyle intervention, metformin, or placebo. MAIN OUTCOMES Associations of steroid sex hormones, SHBG, and SHBG SNPs with glycemia and diabetes risk factors, and with incident diabetes over median 3.0 years (maximum, 5.0 y). RESULTS T and DHT were inversely associated with fasting glucose in men, and estrone sulfate was directly associated with 2-hour post-challenge glucose in men and premenopausal women. SHBG was associated with fasting glucose in premenopausal women not taking exogenous sex hormones, and in postmenopausal women taking exogenous sex hormones, but not in the other groups. Diabetes incidence was directly associated with estrone and estradiol and inversely with T in men; the association with T was lost after adjustment for waist circumference. Sex steroids were not associated with diabetes outcomes in women. SHBG and SHBG SNPs did not predict incident diabetes in the DPP population. CONCLUSIONS Estrogens and T predicted diabetes risk in men but not in women. SHBG and its polymorphisms did not predict risk in men or women. Diabetes risk is more potently determined by obesity and glycemia than by sex hormones.
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Affiliation(s)
- K J Mather
- Department of Medicine (K.J.M.), Indiana University, Indianapolis, Indiana 46202; Departments of Medicine and Obstetrics & Gynecology (C.K.), University of Michigan, Ann Arbor, Michigan 48109; Biostatistics Center (C.A.C., S.E.E.), George Washington University, Rockville, Maryland 20850; Medstar Health Research Institute (V.R.A.), Hyattsville, Maryland 20782; National Institute of Diabetes and Digestive and Kidney Diseases (W.C.K.), Phoenix, Arizona 85014; Diabetes Research Center (Diabetes Unit) and Center for Human Genetics Research (J.C.F.), Massachusetts General Hospital, Boston, Massachusetts 02114; Program in Medical and Population Genetics (J.C.F.), Broad Institute, Cambridge, Massachusetts 02142; Department of Medicine (J.C.F.), Harvard Medical School, Boston, Massachusetts 02115; Endoceutics Inc. (F.L.), Québec City, G1W 2J5, Canada; VA Puget Sound Health Care System and University of Washington (S.E.K.), Seattle, Washington 98108; University of Miami (R.B.G.), Miami, Florida 33124; and University of California, San Diego (E.B.-C.), San Diego, California 92093
| | - C Kim
- Department of Medicine (K.J.M.), Indiana University, Indianapolis, Indiana 46202; Departments of Medicine and Obstetrics & Gynecology (C.K.), University of Michigan, Ann Arbor, Michigan 48109; Biostatistics Center (C.A.C., S.E.E.), George Washington University, Rockville, Maryland 20850; Medstar Health Research Institute (V.R.A.), Hyattsville, Maryland 20782; National Institute of Diabetes and Digestive and Kidney Diseases (W.C.K.), Phoenix, Arizona 85014; Diabetes Research Center (Diabetes Unit) and Center for Human Genetics Research (J.C.F.), Massachusetts General Hospital, Boston, Massachusetts 02114; Program in Medical and Population Genetics (J.C.F.), Broad Institute, Cambridge, Massachusetts 02142; Department of Medicine (J.C.F.), Harvard Medical School, Boston, Massachusetts 02115; Endoceutics Inc. (F.L.), Québec City, G1W 2J5, Canada; VA Puget Sound Health Care System and University of Washington (S.E.K.), Seattle, Washington 98108; University of Miami (R.B.G.), Miami, Florida 33124; and University of California, San Diego (E.B.-C.), San Diego, California 92093
| | - C A Christophi
- Department of Medicine (K.J.M.), Indiana University, Indianapolis, Indiana 46202; Departments of Medicine and Obstetrics & Gynecology (C.K.), University of Michigan, Ann Arbor, Michigan 48109; Biostatistics Center (C.A.C., S.E.E.), George Washington University, Rockville, Maryland 20850; Medstar Health Research Institute (V.R.A.), Hyattsville, Maryland 20782; National Institute of Diabetes and Digestive and Kidney Diseases (W.C.K.), Phoenix, Arizona 85014; Diabetes Research Center (Diabetes Unit) and Center for Human Genetics Research (J.C.F.), Massachusetts General Hospital, Boston, Massachusetts 02114; Program in Medical and Population Genetics (J.C.F.), Broad Institute, Cambridge, Massachusetts 02142; Department of Medicine (J.C.F.), Harvard Medical School, Boston, Massachusetts 02115; Endoceutics Inc. (F.L.), Québec City, G1W 2J5, Canada; VA Puget Sound Health Care System and University of Washington (S.E.K.), Seattle, Washington 98108; University of Miami (R.B.G.), Miami, Florida 33124; and University of California, San Diego (E.B.-C.), San Diego, California 92093
| | - V R Aroda
- Department of Medicine (K.J.M.), Indiana University, Indianapolis, Indiana 46202; Departments of Medicine and Obstetrics & Gynecology (C.K.), University of Michigan, Ann Arbor, Michigan 48109; Biostatistics Center (C.A.C., S.E.E.), George Washington University, Rockville, Maryland 20850; Medstar Health Research Institute (V.R.A.), Hyattsville, Maryland 20782; National Institute of Diabetes and Digestive and Kidney Diseases (W.C.K.), Phoenix, Arizona 85014; Diabetes Research Center (Diabetes Unit) and Center for Human Genetics Research (J.C.F.), Massachusetts General Hospital, Boston, Massachusetts 02114; Program in Medical and Population Genetics (J.C.F.), Broad Institute, Cambridge, Massachusetts 02142; Department of Medicine (J.C.F.), Harvard Medical School, Boston, Massachusetts 02115; Endoceutics Inc. (F.L.), Québec City, G1W 2J5, Canada; VA Puget Sound Health Care System and University of Washington (S.E.K.), Seattle, Washington 98108; University of Miami (R.B.G.), Miami, Florida 33124; and University of California, San Diego (E.B.-C.), San Diego, California 92093
| | - W C Knowler
- Department of Medicine (K.J.M.), Indiana University, Indianapolis, Indiana 46202; Departments of Medicine and Obstetrics & Gynecology (C.K.), University of Michigan, Ann Arbor, Michigan 48109; Biostatistics Center (C.A.C., S.E.E.), George Washington University, Rockville, Maryland 20850; Medstar Health Research Institute (V.R.A.), Hyattsville, Maryland 20782; National Institute of Diabetes and Digestive and Kidney Diseases (W.C.K.), Phoenix, Arizona 85014; Diabetes Research Center (Diabetes Unit) and Center for Human Genetics Research (J.C.F.), Massachusetts General Hospital, Boston, Massachusetts 02114; Program in Medical and Population Genetics (J.C.F.), Broad Institute, Cambridge, Massachusetts 02142; Department of Medicine (J.C.F.), Harvard Medical School, Boston, Massachusetts 02115; Endoceutics Inc. (F.L.), Québec City, G1W 2J5, Canada; VA Puget Sound Health Care System and University of Washington (S.E.K.), Seattle, Washington 98108; University of Miami (R.B.G.), Miami, Florida 33124; and University of California, San Diego (E.B.-C.), San Diego, California 92093
| | - S E Edelstein
- Department of Medicine (K.J.M.), Indiana University, Indianapolis, Indiana 46202; Departments of Medicine and Obstetrics & Gynecology (C.K.), University of Michigan, Ann Arbor, Michigan 48109; Biostatistics Center (C.A.C., S.E.E.), George Washington University, Rockville, Maryland 20850; Medstar Health Research Institute (V.R.A.), Hyattsville, Maryland 20782; National Institute of Diabetes and Digestive and Kidney Diseases (W.C.K.), Phoenix, Arizona 85014; Diabetes Research Center (Diabetes Unit) and Center for Human Genetics Research (J.C.F.), Massachusetts General Hospital, Boston, Massachusetts 02114; Program in Medical and Population Genetics (J.C.F.), Broad Institute, Cambridge, Massachusetts 02142; Department of Medicine (J.C.F.), Harvard Medical School, Boston, Massachusetts 02115; Endoceutics Inc. (F.L.), Québec City, G1W 2J5, Canada; VA Puget Sound Health Care System and University of Washington (S.E.K.), Seattle, Washington 98108; University of Miami (R.B.G.), Miami, Florida 33124; and University of California, San Diego (E.B.-C.), San Diego, California 92093
| | - J C Florez
- Department of Medicine (K.J.M.), Indiana University, Indianapolis, Indiana 46202; Departments of Medicine and Obstetrics & Gynecology (C.K.), University of Michigan, Ann Arbor, Michigan 48109; Biostatistics Center (C.A.C., S.E.E.), George Washington University, Rockville, Maryland 20850; Medstar Health Research Institute (V.R.A.), Hyattsville, Maryland 20782; National Institute of Diabetes and Digestive and Kidney Diseases (W.C.K.), Phoenix, Arizona 85014; Diabetes Research Center (Diabetes Unit) and Center for Human Genetics Research (J.C.F.), Massachusetts General Hospital, Boston, Massachusetts 02114; Program in Medical and Population Genetics (J.C.F.), Broad Institute, Cambridge, Massachusetts 02142; Department of Medicine (J.C.F.), Harvard Medical School, Boston, Massachusetts 02115; Endoceutics Inc. (F.L.), Québec City, G1W 2J5, Canada; VA Puget Sound Health Care System and University of Washington (S.E.K.), Seattle, Washington 98108; University of Miami (R.B.G.), Miami, Florida 33124; and University of California, San Diego (E.B.-C.), San Diego, California 92093
| | - F Labrie
- Department of Medicine (K.J.M.), Indiana University, Indianapolis, Indiana 46202; Departments of Medicine and Obstetrics & Gynecology (C.K.), University of Michigan, Ann Arbor, Michigan 48109; Biostatistics Center (C.A.C., S.E.E.), George Washington University, Rockville, Maryland 20850; Medstar Health Research Institute (V.R.A.), Hyattsville, Maryland 20782; National Institute of Diabetes and Digestive and Kidney Diseases (W.C.K.), Phoenix, Arizona 85014; Diabetes Research Center (Diabetes Unit) and Center for Human Genetics Research (J.C.F.), Massachusetts General Hospital, Boston, Massachusetts 02114; Program in Medical and Population Genetics (J.C.F.), Broad Institute, Cambridge, Massachusetts 02142; Department of Medicine (J.C.F.), Harvard Medical School, Boston, Massachusetts 02115; Endoceutics Inc. (F.L.), Québec City, G1W 2J5, Canada; VA Puget Sound Health Care System and University of Washington (S.E.K.), Seattle, Washington 98108; University of Miami (R.B.G.), Miami, Florida 33124; and University of California, San Diego (E.B.-C.), San Diego, California 92093
| | - S E Kahn
- Department of Medicine (K.J.M.), Indiana University, Indianapolis, Indiana 46202; Departments of Medicine and Obstetrics & Gynecology (C.K.), University of Michigan, Ann Arbor, Michigan 48109; Biostatistics Center (C.A.C., S.E.E.), George Washington University, Rockville, Maryland 20850; Medstar Health Research Institute (V.R.A.), Hyattsville, Maryland 20782; National Institute of Diabetes and Digestive and Kidney Diseases (W.C.K.), Phoenix, Arizona 85014; Diabetes Research Center (Diabetes Unit) and Center for Human Genetics Research (J.C.F.), Massachusetts General Hospital, Boston, Massachusetts 02114; Program in Medical and Population Genetics (J.C.F.), Broad Institute, Cambridge, Massachusetts 02142; Department of Medicine (J.C.F.), Harvard Medical School, Boston, Massachusetts 02115; Endoceutics Inc. (F.L.), Québec City, G1W 2J5, Canada; VA Puget Sound Health Care System and University of Washington (S.E.K.), Seattle, Washington 98108; University of Miami (R.B.G.), Miami, Florida 33124; and University of California, San Diego (E.B.-C.), San Diego, California 92093
| | - R B Goldberg
- Department of Medicine (K.J.M.), Indiana University, Indianapolis, Indiana 46202; Departments of Medicine and Obstetrics & Gynecology (C.K.), University of Michigan, Ann Arbor, Michigan 48109; Biostatistics Center (C.A.C., S.E.E.), George Washington University, Rockville, Maryland 20850; Medstar Health Research Institute (V.R.A.), Hyattsville, Maryland 20782; National Institute of Diabetes and Digestive and Kidney Diseases (W.C.K.), Phoenix, Arizona 85014; Diabetes Research Center (Diabetes Unit) and Center for Human Genetics Research (J.C.F.), Massachusetts General Hospital, Boston, Massachusetts 02114; Program in Medical and Population Genetics (J.C.F.), Broad Institute, Cambridge, Massachusetts 02142; Department of Medicine (J.C.F.), Harvard Medical School, Boston, Massachusetts 02115; Endoceutics Inc. (F.L.), Québec City, G1W 2J5, Canada; VA Puget Sound Health Care System and University of Washington (S.E.K.), Seattle, Washington 98108; University of Miami (R.B.G.), Miami, Florida 33124; and University of California, San Diego (E.B.-C.), San Diego, California 92093
| | - E Barrett-Connor
- Department of Medicine (K.J.M.), Indiana University, Indianapolis, Indiana 46202; Departments of Medicine and Obstetrics & Gynecology (C.K.), University of Michigan, Ann Arbor, Michigan 48109; Biostatistics Center (C.A.C., S.E.E.), George Washington University, Rockville, Maryland 20850; Medstar Health Research Institute (V.R.A.), Hyattsville, Maryland 20782; National Institute of Diabetes and Digestive and Kidney Diseases (W.C.K.), Phoenix, Arizona 85014; Diabetes Research Center (Diabetes Unit) and Center for Human Genetics Research (J.C.F.), Massachusetts General Hospital, Boston, Massachusetts 02114; Program in Medical and Population Genetics (J.C.F.), Broad Institute, Cambridge, Massachusetts 02142; Department of Medicine (J.C.F.), Harvard Medical School, Boston, Massachusetts 02115; Endoceutics Inc. (F.L.), Québec City, G1W 2J5, Canada; VA Puget Sound Health Care System and University of Washington (S.E.K.), Seattle, Washington 98108; University of Miami (R.B.G.), Miami, Florida 33124; and University of California, San Diego (E.B.-C.), San Diego, California 92093
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Affiliation(s)
- R B Goldberg
- University of Miami Miller School of Medicine, Miami, FL.
| | - D Rader
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA.
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Orchard TJ, Temprosa M, Barrett-Connor E, Fowler SE, Goldberg RB, Mather KJ, Marcovina SM, Montez M, Ratner RE, Saudek CD, Sherif H, Watson KE. Long-term effects of the Diabetes Prevention Program interventions on cardiovascular risk factors: a report from the DPP Outcomes Study. Diabet Med 2013; 30:46-55. [PMID: 22812594 PMCID: PMC3524372 DOI: 10.1111/j.1464-5491.2012.03750.x] [Citation(s) in RCA: 138] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
AIMS Whether long-term cardiovascular risk is reduced by the Diabetes Prevention Program interventions is unknown. The aim of this study was to determine the long-term differences in cardiovascular disease risk factors and the use of lipid and blood pressure medications by the original Diabetes Prevention Program intervention group. METHODS This long-term follow-up (median 10 years, interquartile range 9.0-10.5) of the three-arm Diabetes Prevention Program randomized controlled clinical trial (metformin, intensive lifestyle and placebo), performed on 2766 (88%) of the Diabetes Prevention Program participants (who originally had impaired glucose tolerance), comprised a mean of 3.2 years of randomized treatment, approximately 1-year transition (during which all participants were offered intensive lifestyle intervention) and 5 years follow-up (Diabetes Prevention Program Outcomes Study). During the study, participants were followed in their original groups with their clinical care being provided by practitioners outside the research setting. The study determined lipoprotein profiles and blood pressure and medication use annually. RESULTS After 10 years' follow-up from Diabetes Prevention Program baseline, major reductions were seen for systolic (-2 to -3) and diastolic (-6 to -6.5 mmHg) blood pressure, and for LDL cholesterol (-0.51 to -0.6 mmol/l) and triglycerides (-0.23 to -0.25 mmol/l) in all groups, with no between-group differences. HDL cholesterol also rose significantly (0.14 to 0.15 mmol/l) in all groups. Lipid (P = 0.01) and blood pressure (P = 0.09) medication use, however, were lower for the lifestyle group during the Diabetes Prevention Program Outcomes Study. CONCLUSION Overall, intensive lifestyle intervention achieved, with less medication, a comparable long-term effect on cardiovascular disease risk factors, to that seen in the metformin and placebo groups.
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Mather KJ, Christophi CA, Jablonski KA, Knowler WC, Goldberg RB, Kahn SE, Spector T, Dastani Z, Waterworth D, Richards JB, Funahashi T, Pi-Sunyer FX, Pollin TI, Florez JC, Franks PW. Common variants in genes encoding adiponectin (ADIPOQ) and its receptors (ADIPOR1/2), adiponectin concentrations, and diabetes incidence in the Diabetes Prevention Program. Diabet Med 2012; 29:1579-88. [PMID: 22443353 PMCID: PMC3499646 DOI: 10.1111/j.1464-5491.2012.03662.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
AIMS Baseline adiponectin concentrations predict incident Type 2 diabetes mellitus in the Diabetes Prevention Program. We tested the hypothesis that common variants in the genes encoding adiponectin (ADIPOQ) and its receptors (ADIPOR1, ADIPOR2) would associate with circulating adiponectin concentrations and/or with diabetes incidence in the Diabetes Prevention Program population. METHODS Seventy-seven tagging single-nucleotide polymorphisms (SNPs) in ADIPOQ (24), ADIPOR1 (22) and ADIPOR2 (31) were genotyped. Associations of SNPs with baseline adiponectin concentrations were evaluated using linear modelling. Associations of SNPs with diabetes incidence were evaluated using Cox proportional hazards modelling. RESULTS Thirteen of 24 ADIPOQ SNPs were significantly associated with baseline adiponectin concentrations. Multivariable analysis including these 13 SNPs revealed strong independent contributions of rs17366568, rs1648707, rs17373414 and rs1403696 with adiponectin concentrations. However, no ADIPOQ SNPs were directly associated with diabetes incidence. Two ADIPOR1 SNPs (rs1342387 and rs12733285) were associated with ∼18% increased diabetes incidence for carriers of the minor allele without differences across treatment groups, and without any relationship with adiponectin concentrations. CONCLUSIONS ADIPOQ SNPs are significantly associated with adiponectin concentrations in the Diabetes Prevention Program cohort. This observation extends prior observations from unselected populations of European descent into a broader multi-ethnic population, and confirms the relevance of these variants in an obese/dysglycaemic population. Despite the robust relationship between adiponectin concentrations and diabetes risk in this cohort, variants in ADIPOQ that relate to adiponectin concentrations do not relate to diabetes risk in this population. ADIPOR1 variants exerted significant effects on diabetes risk distinct from any effect of adiponectin concentrations.
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Affiliation(s)
- K J Mather
- Division of Endocrinology and Metabolism, Indiana University, Indianapolis, IN, USA.
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Majithia AR, Jablonski KA, McAteer JB, Mather KJ, Goldberg RB, Kahn SE, Florez JC. Association of the SLC30A8 missense polymorphism R325W with proinsulin levels at baseline and after lifestyle, metformin or troglitazone intervention in the Diabetes Prevention Program. Diabetologia 2011; 54:2570-4. [PMID: 21779873 PMCID: PMC3444290 DOI: 10.1007/s00125-011-2234-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/11/2011] [Accepted: 06/08/2011] [Indexed: 10/18/2022]
Abstract
AIMS/HYPOTHESIS Individuals with impaired glucose tolerance have increased proinsulin levels, despite normal glucose or C-peptide levels. In the Diabetes Prevention Program (DPP), increased proinsulin levels predicted type 2 diabetes and proinsulin levels were significantly reduced following treatment with metformin, lifestyle modification or troglitazone compared with placebo. Genetic and physiological studies suggest a role for the zinc transporter gene SLC30A8 in diabetes risk, possibly through effects on insulin-processing in beta cells. We hypothesised that the risk allele at the type 2 diabetes-associated missense polymorphism rs13266634 (R325W) in SLC30A8 would predict proinsulin levels in individuals at risk of type 2 diabetes and may modulate response to preventive interventions. METHODS We genotyped rs13266634 in 3,007 DPP participants and examined its association with fasting proinsulin and fasting insulin at baseline and at 1 year post-intervention. RESULTS We found that increasing dosage of the C risk allele at SLC30A8 rs13266634 was significantly associated with higher proinsulin levels at baseline (p = 0.002) after adjustment for baseline insulin. This supports the hypothesis that risk alleles at SLC30A8 mark individuals with insulin-processing defects. At the 1 year analysis, proinsulin levels decreased significantly in all groups receiving active intervention and were no longer associated with SLC30A8 genotype (p = 0.86) after adjustment for insulin at baseline and 1 year. We found no genotype × treatment interactions at 1 year. CONCLUSIONS/INTERPRETATION In prediabetic individuals, genotype at SLC30A8 predicts baseline proinsulin levels independently of insulin levels, but does not predict proinsulin levels after amelioration of insulin sensitivity at 1 year.
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Affiliation(s)
- A R Majithia
- Center for Human Genetic Research and Diabetes Research Center (Diabetes Unit), Massachusetts General Hospital, Boston, MA, USA
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Beisswenger PJ, Brown WV, Ceriello A, Le NA, Goldberg RB, Cooke JP, Robbins DC, Sarwat S, Yuan H, Jones CA, Tan MH. Meal-induced increases in C-reactive protein, interleukin-6 and tumour necrosis factor α are attenuated by prandial + basal insulin in patients with Type 2 diabetes. Diabet Med 2011; 28:1088-95. [PMID: 21517955 PMCID: PMC3178784 DOI: 10.1111/j.1464-5491.2011.03324.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 04/18/2011] [Indexed: 01/04/2023]
Abstract
AIM To determine if a regimen with prandial + basal insulin compared with basal insulin attenuates post-meal inflammatory and glycative biomarkers in patients with Type 2 diabetes. METHODS This test-meal sub-study in the USA is from a previously reported clinical trial comparing the effect on glycaemic control of 24 weeks of thrice-daily pre-meal insulin lispro mix 50 (50% insulin lispro, 50% insulin lispro protamine suspension) or bedtime insulin glargine, both plus metformin. In the sub-study, glucose, insulin, triglycerides, high-sensitivity C-reactive protein, tumour necrosis factor α, interleukin-6, methylglyoxal and 3-deoxyglucosone were measured during the post-meal period of a mixed-meal breakfast at the final visit. Prandial + basal (n = 25) and basal (n = 21) insulin were administered at the same times as during the previous 24 weeks. RESULTS Post-meal, the prandial + basal insulin group had significantly higher insulin, lower glucose and triglycerides, as well as lower high-sensitivity C-reactive protein, tumour necrosis factor α and interleukin-6, than the basal insulin group. Glucose incremental area under the concentration curve significantly correlated with high-sensitivity C-reactive protein, tumour necrosis factor α, interleukin-6, methylglyoxal and 3-deoxyglucosone incremental area under the concentration curve. Insulin incremental area under the concentration curve correlated inversely with high-sensitivity C-reactive protein and tumour necrosis factor α incremental area under the concentration curve. However, after adjusting for glucose incremental area under the concentration curve, these inverse correlations were no longer significant. Triglyceride incremental area under the concentration curve was not correlated with any biomarker incremental area under the concentration curve. CONCLUSIONS Controlling post-meal hyperglycaemia with prandial + basal insulin in patients with Type 2 diabetes attenuates meal-induced increases in high-sensitivity C-reactive protein, interleukin-6 and tumour necrosis factor α compared with basal insulin. The rise in post-meal glucose, but not triglycerides, significantly correlated with the rise in post-meal inflammatory and glycative biomarkers.
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Affiliation(s)
- P J Beisswenger
- Section of Endocrinology, Diabetes and Metabolism, Dartmouth Medical School and Dartmouth-Hitchcock Medical Center, Hanover, NH, USA
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Abstract
Most differentiation events in higher plants occur continuously in the postembryonic adult phase of the life cycle. Embryogenesis in plants, therefore, is concerned primarily with establishing the basic shoot-root body pattern of the plant and accumulating food reserves that will be used by the germinating seedling after a period of embryonic dormancy within the seed. Recent genetics studies in Arabidopsis have identified genes that provide new insight into how embryos form during plant development. These studies, and others using molecular approaches, are beginning to reveal the underlying processes that control plant embryogenesis.
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Walling L, Drews GN, Goldberg RB. Transcriptional and post-transcriptional regulation of soybean seed protein mRNA levels. Proc Natl Acad Sci U S A 2010; 83:2123-7. [PMID: 16593677 PMCID: PMC323243 DOI: 10.1073/pnas.83.7.2123] [Citation(s) in RCA: 151] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
We investigated soybean seed protein gene transcription during development. We found that seed protein genes are transcriptionally activated and then repressed during embryogenesis and that these genes are either inactive or transcribed at low levels in the mature plant. We further observed that genes encoding mRNAs with vastly different prevalences are transcribed at similar rates. DNA gel blot studies showed that transcriptionally active and inactive seed protein genes have indistinguishable methylation patterns. We conclude that both transcriptional and posttranscriptional processes regulate seed protein mRNA levels in the absence of detectable DNA methylation changes.
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Affiliation(s)
- L Walling
- Department of Biology, University of California, Los Angeles, CA 90024
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Abstract
We transformed tobacco plants with a soybean beta-conglycinin gene that encodes the 1.7-kilobase beta-subunit mRNA. We showed that the beta-conglycinin mRNA accumulates and decays during tobacco seed development and that beta-conglycinin mRNA is undetectable in the tobacco leaf. We utilized in situ hybridization to localize beta-conglycinin mRNA within the tobacco seed. beta-Conglycinin mRNA is not detectable within the endosperm but is localized within specific embryonic cell types. The highest concentration of beta-conglycinin mRNA is found in cotyledon storage parenchyma cells. We conclude that sequences required for embryo expression, temporal control, and cell specificity are linked to the beta-conglycinin gene, and that factors regulating beta-conglycinin gene expression are compartmentalized within analogous soybean and tobacco seed regions.
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Affiliation(s)
- S J Barker
- Department of Biology, University of California, Los Angeles, CA 90024
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11
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Abstract
Experiments are described that characterize the organization of DNA sequences in the water mold Achlya bisexualis. These experiments demonstrate that repetitive and single copy sequences in the Achlya genome are arranged in a long-period interspersion pattern. Estimates of the spacing intervals between repetitive and single copy DNA indicate, however, that the interspersion pattern in Achlya is longer than has been previously reported in other eukaryotes. These data and measurements of structural gene expression in Achlya [Timberlake, W.E., Shumard, D. S. & Goldberg, R. B. (1977) Cell 10, 623-632] make it difficult to propose a regulatory function for repeated DNA in this eukaryote.
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Affiliation(s)
- M E Hudspeth
- Department of Biology, Wayne State University, Detroit, Michigan 48202
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12
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Gleick PH, Adams RM, Amasino RM, Anders E, Anderson DJ, Anderson WW, Anselin LE, Arroyo MK, Asfaw B, Ayala FJ, Bax A, Bebbington AJ, Bell G, Bennett MVL, Bennetzen JL, Berenbaum MR, Berlin OB, Bjorkman PJ, Blackburn E, Blamont JE, Botchan MR, Boyer JS, Boyle EA, Branton D, Briggs SP, Briggs WR, Brill WJ, Britten RJ, Broecker WS, Brown JH, Brown PO, Brunger AT, Cairns J, Canfield DE, Carpenter SR, Carrington JC, Cashmore AR, Castilla JC, Cazenave A, Chapin FS, Ciechanover AJ, Clapham DE, Clark WC, Clayton RN, Coe MD, Conwell EM, Cowling EB, Cowling RM, Cox CS, Croteau RB, Crothers DM, Crutzen PJ, Daily GC, Dalrymple GB, Dangl JL, Darst SA, Davies DR, Davis MB, De Camilli PV, Dean C, DeFries RS, Deisenhofer J, Delmer DP, DeLong EF, DeRosier DJ, Diener TO, Dirzo R, Dixon JE, Donoghue MJ, Doolittle RF, Dunne T, Ehrlich PR, Eisenstadt SN, Eisner T, Emanuel KA, Englander SW, Ernst WG, Falkowski PG, Feher G, Ferejohn JA, Fersht A, Fischer EH, Fischer R, Flannery KV, Frank J, Frey PA, Fridovich I, Frieden C, Futuyma DJ, Gardner WR, Garrett CJR, Gilbert W, Goldberg RB, Goodenough WH, Goodman CS, Goodman M, Greengard P, Hake S, Hammel G, Hanson S, Harrison SC, Hart SR, Hartl DL, Haselkorn R, Hawkes K, Hayes JM, Hille B, Hökfelt T, House JS, Hout M, Hunten DM, Izquierdo IA, Jagendorf AT, Janzen DH, Jeanloz R, Jencks CS, Jury WA, Kaback HR, Kailath T, Kay P, Kay SA, Kennedy D, Kerr A, Kessler RC, Khush GS, Kieffer SW, Kirch PV, Kirk K, Kivelson MG, Klinman JP, Klug A, Knopoff L, Kornberg H, Kutzbach JE, Lagarias JC, Lambeck K, Landy A, Langmuir CH, Larkins BA, Le Pichon XT, Lenski RE, Leopold EB, Levin SA, Levitt M, Likens GE, Lippincott-Schwartz J, Lorand L, Lovejoy CO, Lynch M, Mabogunje AL, Malone TF, Manabe S, Marcus J, Massey DS, McWilliams JC, Medina E, Melosh HJ, Meltzer DJ, Michener CD, Miles EL, Mooney HA, Moore PB, Morel FMM, Mosley-Thompson ES, Moss B, Munk WH, Myers N, Nair GB, Nathans J, Nester EW, Nicoll RA, Novick RP, O'Connell JF, Olsen PE, Opdyke ND, Oster GF, Ostrom E, Pace NR, Paine RT, Palmiter RD, Pedlosky J, Petsko GA, Pettengill GH, Philander SG, Piperno DR, Pollard TD, Price PB, Reichard PA, Reskin BF, Ricklefs RE, Rivest RL, Roberts JD, Romney AK, Rossmann MG, Russell DW, Rutter WJ, Sabloff JA, Sagdeev RZ, Sahlins MD, Salmond A, Sanes JR, Schekman R, Schellnhuber J, Schindler DW, Schmitt J, Schneider SH, Schramm VL, Sederoff RR, Shatz CJ, Sherman F, Sidman RL, Sieh K, Simons EL, Singer BH, Singer MF, Skyrms B, Sleep NH, Smith BD, Snyder SH, Sokal RR, Spencer CS, Steitz TA, Strier KB, Südhof TC, Taylor SS, Terborgh J, Thomas DH, Thompson LG, Tjian RT, Turner MG, Uyeda S, Valentine JW, Valentine JS, Van Etten JL, van Holde KE, Vaughan M, Verba S, von Hippel PH, Wake DB, Walker A, Walker JE, Watson EB, Watson PJ, Weigel D, Wessler SR, West-Eberhard MJ, White TD, Wilson WJ, Wolfenden RV, Wood JA, Woodwell GM, Wright HE, Wu C, Wunsch C, Zoback ML. Climate change and the integrity of science. Science 2010; 328:689-90. [PMID: 20448167 DOI: 10.1126/science.328.5979.689] [Citation(s) in RCA: 102] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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13
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Tomassini JE, Mazzone T, Goldberg RB, Guyton JR, Weinstock RS, Polis A, Jensen E, Tershakovec AM. Effect of ezetimibe/simvastatin compared with atorvastatin on lipoprotein subclasses in patients with type 2 diabetes and hypercholesterolaemia. Diabetes Obes Metab 2009; 11:855-64. [PMID: 19508464 DOI: 10.1111/j.1463-1326.2009.01061.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
AIM To evaluate the effects of the usual starting and next higher doses of ezetimibe/simvastatin and atorvastatin on the cholesterol content of lipoprotein subclasses in patients with type 2 diabetes and hypercholesterolaemia. METHODS This post hoc analysis compared the effects of treatment with ezetimibe/simvastatin 10/20 mg vs. atorvastatin 10 and 20 mg/day and ezetimibe/simvastatin 10/40 mg/day vs. atorvastatin 40 mg/day on the cholesterol content of lipoprotein subclasses in the modified intent-to-treat (mITT) population (n = 1013) and in subgroups of patients with triglyceride (TG) levels <200 mg/dl (n = 600) and >or=200 mg/dl (2.6 mmol/l) (n = 413). RESULTS Ezetimibe/simvastatin significantly reduced low-density lipoprotein cholesterol (LDL-C) subclasses LDL(1)-C, LDL(2)-C and LDL(3)-C; real LDL-C (LDL-C(r)); intermediate-density lipoprotein cholesterol (IDL-C), IDL(1)-C, IDL(2)-C; very low-density lipoprotein cholesterol (VLDL-C), VLDL(3)-C; and remnant-like lipoprotein cholesterol (RLP-C) from baseline more than atorvastatin at all dose comparisons (p < 0.01) in the mITT population. Significant improvements were also observed in high-density lipoprotein cholesterol (HDL-C) subclass HDL(3)-C at the ezetimibe/simvastatin 10/20 mg vs. atorvastatin 20 mg and highest dose comparisons (p < 0.001) and in VLDL(1 + 2)-C at the lowest and highest dose comparisons (p < 0.001). Changes in LDL(4)-C and LDL-C subclass patterns (A, B and I) were comparable for both treatments. Generally, similar results were observed for patients with TG levels <200 and >or=200 mg/dl (2.3 mmol). For both treatments, notable differences between TG subgroups were that patients with elevated TGs had smaller reductions in LDL(2)-C, slightly smaller decreases in all IDL subclasses and greater decreases in all VLDL-C subclasses than those with lower TG levels. Frequency of pattern B was also reduced more in patients with higher TGs for both treatments. CONCLUSIONS Ezetimibe/simvastatin reduced the cholesterol content of most lipoprotein subclasses from baseline with generally similar efficacy in patients with low and high TGs. Despite the different mechanism of action of ezetimibe, the response to ezetimibe/simvastatin and atorvastatin treatment related to these lipoprotein subclasses was generally consistent with the overall effects of these therapies on the major lipid/lipoprotein classes. The clinical significance of these results awaits further study.
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Affiliation(s)
- J E Tomassini
- Clinical and Quantitative Sciences, Merck & Co., Inc., North Wales, PA, USA
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14
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Abstract
The separation of mouse spermatogenic cell nuclei by sedimentation velocity at unit gravity has been used to determine the timing of histone and "mouse protamine" synthesis, and the turnover of basic nuclear proteins throughout spermatogenesis. Animals were injected with 3H-arginine or 3H-lysine and at various time intervals (2 hours post-label or from 1 to 30 days post-label) germinal cell nuclei preparations were separated on the staput. Labelled histones and mouse protamine were extracted from staput separated nuclei with hydrocholoric acid and fractionated by polyacrylamide gel electrophoresis. Results indicate that histones are synthesized in association with DNA replication in spermatogonia and preleptotene spermatocytes, in pachytene primary spermatocytes and in spermatids stages 11-16, simultaneously with "mouse protamine". Experiments are reported showing that histones synthesized in pachytene primary spermatocytes and in spermatids stages 11-16 are retained in epididymal spermatozoa, while histones synthesized before meiosis are no longer detectable onto chromatin after meiosis.
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15
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Solano MP, Perry AC, Wang X, Ross R, Goldberg RB. Insulin resistance but not visceral adipose tissue is associated with plasminogen activator inhibitor type 1 levels in overweight and obese premenopausal African-American women. Int J Obes (Lond) 2003; 27:82-7. [PMID: 12532158 DOI: 10.1038/sj.ijo.0802192] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/02/2002] [Revised: 07/25/2002] [Accepted: 08/13/2002] [Indexed: 11/09/2022]
Abstract
OBJECTIVE To compare plasma plasminogen activator inhibitor type 1 (PAI-1) levels and to examine the association of PAI-1 with visceral adiposity and other components of the metabolic syndrome in overweight and obese premenopausal African-American (AA) and Caucasian (CC) women. DESIGN Cross-sectional study. SUBJECTS 33 CC and 23 AA healthy, overweight and obese, premenopausal women (age 19-53 y, body mass index 28.1-48.9 kg/m(2)). MEASUREMENTS Body mass index, sagittal diameter, waist circumference, percentage body fat, visceral and subcutaneous adipose tissue (by anthropometry, magnetic resonance imaging (MRI), and bioelectric impedance techniques), PAI-1, leptin, lipids, glucose, insulin, and insulin resistance (by HOMA IR). RESULTS AA women had lower triglyceride levels and less visceral adipose tissue (VAT) volume than CC despite similar BMI. PAI-1 levels were not significantly different in the two groups. Insulin resistance was associated with PAI-1 in both groups but only in CC women were VAT, triglyceride, HDL cholesterol and blood pressure related to plasma PAI-1 levels. Multiple regression analysis showed that VAT in CC and insulin resistance in AA were independent predictors of PAI-1. CONCLUSION VAT is significantly associated with circulating PAI-1 levels in overweight and obese CC but not AA premenopausal women.
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Affiliation(s)
- M P Solano
- Department of Medicine, University of Miami School of Medicine, Miami, Florida 33136, USA.
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16
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Abstract
BACKGROUND People with chronic paraplegia frequently experience dyslipidemias characterized by depressed levels of high-density lipoprotein cholesterol (HDL-C) and elevated levels of low-density lipoprotein cholesterol (LDL-C). These abnormal lipid profiles and poor fitness levels increase their risk for cardiovascular disease. METHODS To test the hypothesis that circuit resistance exercise training improves both upper-extremity fitness and the atherogenic lipid profile in persons with chronic paraplegia, a homogeneous cohort of 5 men with neurologically complete spinal cord injuries at T6 to L1 underwent 3 months of exercise training using uninterrupted resistance and endurance exercises of the upper extremities. Training was performed 3 times a week on alternating days. RESULTS Results of graded arm exercise testing showed a 30.3% improvement in peak oxygen consumption (P < .01), a 33.5% increase in time to fatigue (P < .01) and a 30.4% increase in peak power output (P < .05). Pretraining total cholesterol levels (TC) were in the low-risk category and were nonsignificantly lowered following training. Similar nonsignificant reductions of plasma triglycerides averaging 12 mg/dL were attained. Conversely, a 25.9% lowering of LDL-C (P < .05) and 9.8% elevation of HDL-C (P < .05) were observed after training. These changes reduced the average LDL-C-to-HDL-C ratio by 1 unit (P < .05) and the TC-to-HDL-C ratio from 5.0 +/- 1.1 (mean +/- SD) to 3.9 +/- 0.7 (P < .05). CONCLUSIONS This change reflects a cardiovascular risk reduction of almost 25%; the TC/HDL-C declined from the high-risk score of 5.0 to near the desired score of 3.5. These findings support the beneficial effects of circuit exercise resistance training on fitness and atherogenic lipid profiles in persons with chronic paraplegia.
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Affiliation(s)
- M S Nash
- Department of Orthopaedics and Rehabilitation, University of Miami School of Medicine, Florida 33146, USA.
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17
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Abstract
All plants flower late in their life cycle. For example, in Arabidopsis, the shoot undergoes a transition and produces reproductive flowers after the adult phase of vegetative growth. Much is known about genetic and environmental processes that control flowering time in mature plants. However, little is understood about the mechanisms that prevent plants from flowering much earlier during embryo and seedling development. Arabidopsis embryonic flower (emf1 and emf2) mutants flower soon after germination, suggesting that a floral repression mechanism is established in wild-type plants that prevents flowering until maturity. Here, we show that polycomb group proteins play a central role in repressing flowering early in the plant life cycle. We found that mutations in the Fertilization Independent Endosperm (FIE) polycomb gene caused the seedling shoot to produce flower-like structures and organs. Flower-like structures were also generated from the hypocotyl and root, organs not associated with reproduction. Expression of floral induction and homeotic genes was derepressed in mutant embryos and seedlings. These results suggest that FIE-mediated polycomb complexes are an essential component of a floral repression mechanism established early during plant development.
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Affiliation(s)
- T Kinoshita
- Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720, USA
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18
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Abstract
We investigated gene activity within the giant embryos of the scarlet runner bean (Phaseolus coccineus) to gain understanding of the processes by which the apical and basal cells become specified to follow different developmental pathways after division of the zygote. We identified two mRNAs, designated G564 and C541, that accumulate specifically within the suspensor of globular-stage embryos. G564 mRNA accumulates uniformly throughout the suspensor, whereas C541 mRNA accumulates to a higher level within the large basal cells of the suspensor that anchor the embryo to the surrounding seed tissue. Both G564 and C541 mRNAs begin to accumulate shortly after fertilization and are present within the two basal cells of embryos at the four-cell stage. In contrast, at the same stage, these mRNAs are not detectable within the two descendants of the apical cell. Nor are they detectable within cells of the embryo sac before fertilization, including the egg cell. We used a G564/beta-glucuronidase reporter gene to show that the G564 promoter is activated specifically within the basal region and suspensor of preglobular tobacco embryos. Analysis of the G564 promoter identified a sequence domain required for transcription within the suspensor that contains several copies of a conserved motif. These results show that derivatives of the apical and basal cells transcribe different genes as early as the four-cell stage of embryo development and suggest that the apical and basal cells are specified at the molecular level after division of the zygote.
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MESH Headings
- Base Sequence
- Gene Expression Regulation, Plant
- Gene Library
- Genes, Reporter
- In Situ Hybridization
- Molecular Sequence Data
- Phaseolus/growth & development
- Plants, Genetically Modified
- Promoter Regions, Genetic
- RNA, Messenger/genetics
- RNA, Plant/genetics
- RNA, Plant/isolation & purification
- Reverse Transcriptase Polymerase Chain Reaction
- Seeds/physiology
- Sequence Alignment
- Sequence Homology, Nucleic Acid
- Tobacco/genetics
- Transcription, Genetic
- Transformation, Genetic
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Affiliation(s)
- K Weterings
- Department of Molecular, Cell, and Developmental Biology, University of California, Los Angeles, California 90095-1606, USA
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19
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Weterings K, Apuya NR, Bi Y, Fischer RL, Harada JJ, Goldberg RB. Regional localization of suspensor mRNAs during early embryo development. Plant Cell 2001; 13:2409-25. [PMID: 11701878 PMCID: PMC139461 DOI: 10.1105/tpc.010326] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2001] [Accepted: 09/07/2001] [Indexed: 05/23/2023]
Abstract
We investigated gene activity within the giant embryos of the scarlet runner bean (Phaseolus coccineus) to gain understanding of the processes by which the apical and basal cells become specified to follow different developmental pathways after division of the zygote. We identified two mRNAs, designated G564 and C541, that accumulate specifically within the suspensor of globular-stage embryos. G564 mRNA accumulates uniformly throughout the suspensor, whereas C541 mRNA accumulates to a higher level within the large basal cells of the suspensor that anchor the embryo to the surrounding seed tissue. Both G564 and C541 mRNAs begin to accumulate shortly after fertilization and are present within the two basal cells of embryos at the four-cell stage. In contrast, at the same stage, these mRNAs are not detectable within the two descendants of the apical cell. Nor are they detectable within cells of the embryo sac before fertilization, including the egg cell. We used a G564/beta-glucuronidase reporter gene to show that the G564 promoter is activated specifically within the basal region and suspensor of preglobular tobacco embryos. Analysis of the G564 promoter identified a sequence domain required for transcription within the suspensor that contains several copies of a conserved motif. These results show that derivatives of the apical and basal cells transcribe different genes as early as the four-cell stage of embryo development and suggest that the apical and basal cells are specified at the molecular level after division of the zygote.
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MESH Headings
- Base Sequence
- Gene Expression Regulation, Plant
- Gene Library
- Genes, Reporter
- In Situ Hybridization
- Molecular Sequence Data
- Phaseolus/growth & development
- Plants, Genetically Modified
- Promoter Regions, Genetic
- RNA, Messenger/genetics
- RNA, Plant/genetics
- RNA, Plant/isolation & purification
- Reverse Transcriptase Polymerase Chain Reaction
- Seeds/physiology
- Sequence Alignment
- Sequence Homology, Nucleic Acid
- Nicotiana/genetics
- Transcription, Genetic
- Transformation, Genetic
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Affiliation(s)
- K Weterings
- Department of Molecular, Cell, and Developmental Biology, University of California, Los Angeles, California 90095-1606, USA
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20
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Stone SL, Kwong LW, Yee KM, Pelletier J, Lepiniec L, Fischer RL, Goldberg RB, Harada JJ. LEAFY COTYLEDON2 encodes a B3 domain transcription factor that induces embryo development. Proc Natl Acad Sci U S A 2001; 98:11806-11811. [PMID: 11573014 DOI: 10.1073/pnas/201413498] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/18/2023] Open
Abstract
The Arabidopsis LEAFY COTYLEDON2 (LEC2) gene is a central embryonic regulator that serves critical roles both early and late during embryo development. LEC2 is required for the maintenance of suspensor morphology, specification of cotyledon identity, progression through the maturation phase, and suppression of premature germination. We cloned the LEC2 gene on the basis of its chromosomal position and showed that the predicted polypeptide contains a B3 domain, a DNA-binding motif unique to plants that is characteristic of several transcription factors. We showed that LEC2 RNA accumulates primarily during seed development, consistent with our finding that LEC2 shares greatest similarity with the B3 domain transcription factors that act primarily in developing seeds, VIVIPAROUS1/ABA INSENSITIVE3 and FUSCA3. Ectopic, postembryonic expression of LEC2 in transgenic plants induces the formation of somatic embryos and other organ-like structures and often confers embryonic characteristics to seedlings. Together, these results suggest that LEC2 is a transcriptional regulator that establishes a cellular environment sufficient to initiate embryo development.
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Affiliation(s)
- S L Stone
- Section of Plant Biology, Division of Biological Sciences, University of California, One Shields Avenue, Davis, CA 95616, USA
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21
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Stone SL, Kwong LW, Yee KM, Pelletier J, Lepiniec L, Fischer RL, Goldberg RB, Harada JJ. LEAFY COTYLEDON2 encodes a B3 domain transcription factor that induces embryo development. Proc Natl Acad Sci U S A 2001; 98:11806-11. [PMID: 11573014 PMCID: PMC58812 DOI: 10.1073/pnas.201413498] [Citation(s) in RCA: 486] [Impact Index Per Article: 21.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/06/2001] [Indexed: 11/18/2022] Open
Abstract
The Arabidopsis LEAFY COTYLEDON2 (LEC2) gene is a central embryonic regulator that serves critical roles both early and late during embryo development. LEC2 is required for the maintenance of suspensor morphology, specification of cotyledon identity, progression through the maturation phase, and suppression of premature germination. We cloned the LEC2 gene on the basis of its chromosomal position and showed that the predicted polypeptide contains a B3 domain, a DNA-binding motif unique to plants that is characteristic of several transcription factors. We showed that LEC2 RNA accumulates primarily during seed development, consistent with our finding that LEC2 shares greatest similarity with the B3 domain transcription factors that act primarily in developing seeds, VIVIPAROUS1/ABA INSENSITIVE3 and FUSCA3. Ectopic, postembryonic expression of LEC2 in transgenic plants induces the formation of somatic embryos and other organ-like structures and often confers embryonic characteristics to seedlings. Together, these results suggest that LEC2 is a transcriptional regulator that establishes a cellular environment sufficient to initiate embryo development.
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Affiliation(s)
- S L Stone
- Section of Plant Biology, Division of Biological Sciences, University of California, One Shields Avenue, Davis, CA 95616, USA
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22
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Apuya NR, Yadegari R, Fischer RL, Harada JJ, Zimmerman JL, Goldberg RB. The Arabidopsis embryo mutant schlepperless has a defect in the chaperonin-60alpha gene. Plant Physiol 2001; 126:717-30. [PMID: 11402200 PMCID: PMC111162 DOI: 10.1104/pp.126.2.717] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2001] [Revised: 03/26/2001] [Accepted: 03/30/2001] [Indexed: 05/18/2023]
Abstract
We identified a T-DNA-generated mutation in the chaperonin-60alpha gene of Arabidopsis that produces a defect in embryo development. The mutation, termed schlepperless (slp), causes retardation of embryo development before the heart stage, even though embryo morphology remains normal. Beyond the heart stage, the slp mutation results in defective embryos with highly reduced cotyledons. slp embryos exhibit a normal apical-basal pattern and radial tissue organization, but they are morphologically retarded. Even though slp embryos are competent to transcribe two late-maturation gene markers, this competence is acquired more slowly as compared with wild-type embryos. slp embryos also exhibit a defect in plastid development-they remain white during maturation in planta and in culture. Hence, the overall developmental phenotype of the slp mutant reflects a lesion in the chloroplast that affects embryo development. The slp phenotype highlights the importance of the chaperonin-60alpha protein for chloroplast development and subsequently for the proper development of the plant embryo and seedling.
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Affiliation(s)
- N R Apuya
- Department of Molecular, Cell, and Developmental Biology, University of California, 621 Charles E. Young Avenue, Los Angeles, California 90095, USA
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23
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Goldberg RB, Capuzzi D. Lipid disorders in type 1 and type 2 diabetes. Clin Lab Med 2001; 21:147-72, vii. [PMID: 11321932] [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: 02/19/2023]
Abstract
Atherosclerotic cardiovascular disease is the most important cause of morbidity and mortality in diabetic subjects. Abnormalities in circulating lipids and lipoproteins are considered to be important risk factors for cardiovascular disease because they occur with increased frequency in diabetic individuals. Because reversal of these abnormalities carries the potential for preventing or ameliorating cardiovascular disease, their identification and management with other cardiovascular disease risk factors deserve equal importance to the management of hyperglycemia and frequently are complementary to it.
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Affiliation(s)
- R B Goldberg
- Diabetes Research Institute, University of Miami, Miami, Florida, USA
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24
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Solano MP, Kumar M, Fernandez B, Jones L, Goldberg RB. The pituitary response to ovine corticotropin-releasing hormone is enhanced in obese men and correlates with insulin resistance. Horm Metab Res 2001; 33:39-43. [PMID: 11280714 DOI: 10.1055/s-2001-12625] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
Hyperactivity of the hypothalamic-pituitary-adrenal (HPA) axis in central obesity has been demonstrated in women. We studied the corticotropin (ACTH) and cortisol response to ovine corticotropin releasing hormone (oCRH) and its association to parameters of adiposity and insulin resistance in a group of 19 healthy obese (BMI > 25 kg/m2) and 9 non-obese men. Relative insulin resistance was assessed by the homeostatic model assessment (HOMA IR). Baseline ACTH was similar, while cortisol was lower in the obese group. The ACTH response to oCRH was significantly higher in the obese group. ACTH incremental area under the curve (iAUC) correlated with age, HOMA IR, and sagittal diameter but not with leptin. In multiple regression analysis, only HOMA IR was an independent predictor of ACTH iAUC. In conclusion, obese men have hyperactivity of the HPA axis at the pituitary level, which appears to be linked to insulin resistance.
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Affiliation(s)
- M P Solano
- Department of Medicine, University of Miami School of Medicine, FL 33136, USA.
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25
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Affiliation(s)
- R B Goldberg
- Department of Molecular, Cell, and Developmental Biology, University of California, Los Angeles, California 90095-1606, USA.
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26
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Yadegari R, Kinoshita T, Lotan O, Cohen G, Katz A, Choi Y, Katz A, Nakashima K, Harada JJ, Goldberg RB, Fischer RL, Ohad N. Mutations in the FIE and MEA genes that encode interacting polycomb proteins cause parent-of-origin effects on seed development by distinct mechanisms. Plant Cell 2000; 12:2367-2382. [PMID: 11148284 PMCID: PMC102224 DOI: 10.1105/tpc.12.12.2367] [Citation(s) in RCA: 112] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2000] [Accepted: 10/19/2000] [Indexed: 05/17/2023]
Abstract
In flowering plants, two cells are fertilized in the haploid female gametophyte. Egg and sperm nuclei fuse to form the embryo. A second sperm nucleus fuses with the central cell nucleus, which replicates to generate the endosperm, a tissue that supports embryo development. The FERTILIZATION-INDEPENDENT ENDOSPERM (FIE) and MEDEA (MEA) genes encode WD and SET domain polycomb proteins, respectively. In the absence of fertilization, a female gametophyte with a loss-of-function fie or mea allele initiates endosperm development without fertilization. fie and mea mutations also cause parent-of-origin effects, in which the wild-type maternal allele is essential and the paternal allele is dispensable for seed viability. Here, we show that FIE and MEA polycomb proteins interact physically, suggesting that the molecular partnership of WD and SET domain polycomb proteins has been conserved during the evolution of flowering plants. The overlapping expression patterns of FIE and MEA are consistent with their suppression of gene transcription and endosperm development in the central cell as well as their control of seed development after fertilization. Although FIE and MEA interact, differences in maternal versus paternal patterns of expression, as well as the effect of a recessive mutation in the DECREASE IN DNA METHYLATION1 (DDM1) gene on mutant allele transmission, indicate that fie and mea mutations cause parent-of-origin effects on seed development by distinct mechanisms.
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Affiliation(s)
- R Yadegari
- Department of Plant and Microbial Biology, University of California, Berkeley, California 94720-3102, USA
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Goldberg RB. Hyperlipidemia and cardiovascular risk factors in patients with type 2 diabetes. Am J Manag Care 2000; 6:S682-91; discussion S692-6. [PMID: 11183421] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
Atherosclerosis accounts for approximately 80% of all mortality caused by diabetes and for most hospitalizations necessitated by the complications of diabetes. Overall, individuals with diabetes have a 2- to 3-fold increased risk of cardiovascular disease compared with that in individuals without diabetes. The major risk factors contributing to the excess of cardiovascular disease caused by diabetes include: hyperglycemia, insulin resistance, dyslipidemia, hypertension, smoking, albuminuria, and the procoagulant state. Although the low-density lipoprotein (LDL) and total cholesterol levels of patients with diabetes are similar to those of the nondiabetic population, triglyceride levels are usually higher in those with diabetes. Evaluation of results in the subsets of the large Scandinavian Simvastatin Survival Study (4S) and the Cholesterol and Recurrent Events (CARE) trials that include subjects with diabetes indicates that cholesterol-lowering drugs can significantly reduce the cardiovascular event rate in patients with diabetes. Current options for the management of cardiovascular risk factors in those with diabetes include lowering the LDL cholesterol level below 100 mg/dL, lowering blood pressure below 130/85 mm Hg, improving hyperglycemia and the atherogenic lipid profile (i.e., triglyceride and high-density lipoprotein [HDL] levels), treating microalbuminuria, reducing insulin resistance, and using aspirin to reduce the clotting risk.
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Perry AC, Applegate EB, Jackson ML, Deprima S, Goldberg RB, Ross R, Kempner L, Feldman BB. Racial differences in visceral adipose tissue but not anthropometric markers of health-related variables. J Appl Physiol (1985) 2000; 89:636-43. [PMID: 10926648 DOI: 10.1152/jappl.2000.89.2.636] [Citation(s) in RCA: 83] [Impact Index Per Article: 3.5] [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: 11/22/2022] Open
Abstract
This study sought to determine whether visceral adipose tissue (VAT) and/or its anthropometric surrogates could significantly predict health-related variables (HRV) in overweight Caucasian (CC) (n = 36) and African-American (AA) (n = 30) women. With the use of magnetic resonance imaging, findings showed significantly higher volume and area of VAT (P < 0.0001 for both) as well as higher triacylglycerol (P = 0.009) in CC compared with AA women. Furthermore, VAT volume, race, and VAT volume x race interaction could significantly predict triacylglycerol (P = 0.0094), high-density lipoprotein cholesterol (P = 0.0057), insulin (P = 0.0002), and insulin resistance (P < 0. 0001). Additionally, the VAT volume x race interaction for insulin (P = 0.040) and insulin resistance (P = 0.003) was significant. In a separate analysis, waist circumference and race predicted the identical variables. Our results support the use of volume or area of VAT in predicting HRV in CC women; however, its use in AA women appears limited. In contrast, waist circumference can provide a suitable VAT alternative for both CC and AA women; however, VAT clearly represents the more powerful predictor.
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Affiliation(s)
- A C Perry
- Human Performance Laboratory, University of Miami, Coral Gables, Florida 33124-2040, USA.
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Sanders PM, Lee PY, Biesgen C, Boone JD, Beals TP, Weiler EW, Goldberg RB. The arabidopsis DELAYED DEHISCENCE1 gene encodes an enzyme in the jasmonic acid synthesis pathway. Plant Cell 2000; 12:1041-61. [PMID: 10899973 PMCID: PMC149048 DOI: 10.1105/tpc.12.7.1041] [Citation(s) in RCA: 331] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2000] [Accepted: 05/19/2000] [Indexed: 05/17/2023]
Abstract
delayed dehiscence1 is an Arabidopsis T-DNA mutant in which anthers release pollen grains too late for pollination to occur. The delayed dehiscence1 defect is caused by a delay in the stomium degeneration program. The gene disrupted in delayed dehiscence1 encodes 12-oxophytodienoate reductase, an enzyme in the jasmonic acid biosynthesis pathway. We rescued the mutant phenotype by exogenous application of jasmonic acid and obtained seed set from previously male-sterile plants. In situ hybridization studies showed that during the early stages of floral development, DELAYED DEHISCENCE1 mRNA accumulated within all floral organs. Later, DELAYED DEHISCENCE1 mRNA accumulated specifically within the pistil, petals, and stamen filaments. DELAYED DEHISCENCE1 mRNA was not detected in the stomium and septum cells of the anther that are involved in pollen release. The T-DNA insertion in delayed dehiscence1 eliminated both DELAYED DEHISCENCE1 mRNA accumulation and 12-oxophytodienoate reductase activity. These experiments suggest that jasmonic acid signaling plays a role in controlling the time of anther dehiscence within the flower.
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Affiliation(s)
- P M Sanders
- Department of Molecular, Cell, and Developmental Biology, University of California, Los Angeles 90095-1606, USA
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30
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Sanders PM, Lee PY, Biesgen C, Boone JD, Beals TP, Weiler EW, Goldberg RB. The arabidopsis DELAYED DEHISCENCE1 gene encodes an enzyme in the jasmonic acid synthesis pathway. Plant Cell 2000; 12:1041-1061. [PMID: 10899973 DOI: 10.2307/3871254] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
delayed dehiscence1 is an Arabidopsis T-DNA mutant in which anthers release pollen grains too late for pollination to occur. The delayed dehiscence1 defect is caused by a delay in the stomium degeneration program. The gene disrupted in delayed dehiscence1 encodes 12-oxophytodienoate reductase, an enzyme in the jasmonic acid biosynthesis pathway. We rescued the mutant phenotype by exogenous application of jasmonic acid and obtained seed set from previously male-sterile plants. In situ hybridization studies showed that during the early stages of floral development, DELAYED DEHISCENCE1 mRNA accumulated within all floral organs. Later, DELAYED DEHISCENCE1 mRNA accumulated specifically within the pistil, petals, and stamen filaments. DELAYED DEHISCENCE1 mRNA was not detected in the stomium and septum cells of the anther that are involved in pollen release. The T-DNA insertion in delayed dehiscence1 eliminated both DELAYED DEHISCENCE1 mRNA accumulation and 12-oxophytodienoate reductase activity. These experiments suggest that jasmonic acid signaling plays a role in controlling the time of anther dehiscence within the flower.
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Affiliation(s)
- P M Sanders
- Department of Molecular, Cell, and Developmental Biology, University of California, Los Angeles 90095-1606, USA
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31
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Somers DA, Mazur B, Goldberg RB, Bowen B. The impact of molecular biology on crop production and crop protection. Trends Biotechnol 2000; 18:185-6. [PMID: 10917678 DOI: 10.1016/s0167-7799(99)01414-6] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Affiliation(s)
- D A Somers
- Department of Agronomy and Plant Genetics, University of Minnesota, St. Paul 55108, USA.
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Abstract
Cardiovascular disease is the most frequent cause of morbidity and mortality in patients with diabetes. This article evaluates the results of clinical interventions that have been tested for their ability to ameliorate cardiovascular disease through identification and management of cardiovascular risk factors. These include hyperglycemia, insulin resistance, dyslipidemia, hypertension, cigarette smoking, and a procoagulant state. Attention to all cardiovascular risk factors is necessary if physicians are to reduce the burden of these complications in diabetic patients.
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Affiliation(s)
- R B Goldberg
- Department of Medicine, University of Miami, Florida, USA.
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Abstract
In flowering plants, two cells are fertilized in the haploid female gametophyte. Egg and sperm nuclei fuse to form the embryo. A second sperm nucleus fuses with the central cell nucleus that replicates to generate the endosperm, which is a tissue that supports embryo development. MEDEA (MEA) encodes an Arabidopsis SET domain Polycomb protein. Inheritance of a maternal loss-of-function mea allele results in embryo abortion and prolonged endosperm production, irrespective of the genotype of the paternal allele. Thus, only the maternal wild-type MEA allele is required for proper embryo and endosperm development. To understand the molecular mechanism responsible for the parent-of-origin effects of mea mutations on seed development, we compared the expression of maternal and paternal MEA alleles in the progeny of crosses between two Arabidopsis ecotypes. Only the maternal MEA mRNA was detected in the endosperm from seeds at the torpedo stage and later. By contrast, expression of both maternal and paternal MEA alleles was observed in the embryo from seeds at the torpedo stage and later, in seedling, leaf, stem, and root. Thus, MEA is an imprinted gene that displays parent-of-origin-dependent monoallelic expression specifically in the endosperm. These results suggest that the embryo abortion observed in mutant mea seeds is due, at least in part, to a defect in endosperm function. Silencing of the paternal MEA allele in the endosperm and the phenotype of mutant mea seeds supports the parental conflict theory for the evolution of imprinting in plants and mammals.
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Affiliation(s)
- T Kinoshita
- Department of Plant and Microbial Biology, University of California, Berkeley, California 94720-3102, USA
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36
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Donahue RP, Prineas RJ, Donahue RD, Zimmet P, Bean JA, De Courten M, Collier G, Goldberg RB, Skyler JS, Schneiderman N. Is fasting leptin associated with insulin resistance among nondiabetic individuals? The Miami Community Health Study. Diabetes Care 1999; 22:1092-6. [PMID: 10388973 DOI: 10.2337/diacare.22.7.1092] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
OBJECTIVE Whether serum leptin levels are associated with insulin resistance independent of the effects of hyperinsulinemia and adiposity is an important unanswered question. We examined the relationship between the rate of insulin-mediated glucose uptake and serum leptin concentrations among nondiabetic men and women. RESEARCH DESIGN AND METHODS A cross-sectional analysis was performed among 49 young to middle-aged men and women who participated in the Miami Community Health Study. All participants had measures of insulin resistance (euglycemic-hyperinsulinemic clamp), postchallenge insulin levels, fasting serum leptin levels, and several measures of adiposity. RESULTS The rate of insulin-mediated glucose uptake (M in milligrams per kilogram per minute) was significantly associated with leptin concentrations in both men (r = -0.83; P < 0.001) and women (r = -0.59; P < 0.001). M was also inversely related to percent body fat and to the 2-h insulin area under the curve (AUC). After covariate adjustment for sex, percent body fat, and AUC, leptin remained a significant correlate of M (P = 0.04). CONCLUSIONS Cross-sectionally, leptin was significantly associated with insulin resistance in this nondiabetic sample of men and women. There may be a different physiological mechanism to explain the leptin/insulin resistance association apart from the insulin/adiposity link. Confirmatory evidence awaits the results of clinical trials.
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Affiliation(s)
- R P Donahue
- Department of Social and Preventive Medicine, University of Buffalo, NY 14214, USA.
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37
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Kiyosue T, Ohad N, Yadegari R, Hannon M, Dinneny J, Wells D, Katz A, Margossian L, Harada JJ, Goldberg RB, Fischer RL. Control of fertilization-independent endosperm development by the MEDEA polycomb gene in Arabidopsis. Proc Natl Acad Sci U S A 1999; 96:4186-91. [PMID: 10097185 PMCID: PMC22442 DOI: 10.1073/pnas.96.7.4186] [Citation(s) in RCA: 243] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Higher plant reproduction is unique because two cells are fertilized in the haploid female gametophyte. Egg and sperm nuclei fuse to form the embryo. A second sperm nucleus fuses with the central cell nucleus that replicates to generate the endosperm, a tissue that supports embryo development. To understand mechanisms that initiate reproduction, we isolated a mutation in Arabidopsis, f644, that allows for replication of the central cell and subsequent endosperm development without fertilization. When mutant f644 egg and central cells are fertilized by wild-type sperm, embryo development is inhibited, and endosperm is overproduced. By using a map-based strategy, we cloned and sequenced the F644 gene and showed that it encodes a SET-domain polycomb protein. Subsequently, we found that F644 is identical to MEDEA (MEA), a gene whose maternal-derived allele is required for embryogenesis [Grossniklaus, U., Vielle-Calzada, J.-P., Hoeppner, M. A. & Gagliano, W. B. (1998) Science 280, 446-450]. Together, these results reveal functions for plant polycomb proteins in the suppression of central cell proliferation and endosperm development. We discuss models to explain how polycomb proteins function to suppress endosperm and promote embryo development.
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Affiliation(s)
- T Kiyosue
- Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720, USA
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Flórez H, Méndez AJ, Jones L, Goldberg RB. [Gender differences and diabetic status in the relationship of blood apolipoprotein C-III, free fatty acids and triglycerides in subjects at risk for glucose intolerance]. Invest Clin 1999; 40:51-66. [PMID: 10198561] [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: 02/11/2023]
Abstract
Insulin resistance and hyperinsulinemia can induce overproduction of triglyceride (TG) rich VLDL in the liver by increasing the availability of free fatty acids (FFA). Conversely, apolipoprotein C-III (apoC-III) is an inhibitor of the catabolism of TG-rich lipoproteins. To explore the relationship among FFA, apo C-III and TG in hyperinsulinemic subjects, we studied 103 individuals (63 women and 40 men) with a body mass index (BMI) 25 Kg/m2: 59 subjects with normal glucose tolerance (NGT), and 44 with newly diagnosed type 2 diabetes. After adjustment for age, BMI, fasting insulin and TG, FFA were significantly higher in women than in men and in subjects with diabetes compared with NGT. Subjects with diabetes had higher apo C-III levels compared to NGT, adjusted for age, sex and BMI, and that was largely accounted for by differences in insulin and TG levels. In addition, regression analysis in subjects with diabetes showed that TG were strongly associated with apo C-III in both men and women (r = 0.90 and 0.79, respectively; p < 0.001), while the association tended to be smaller between TG and FFA (r = 0.48, p < 0.05 in men and r = 0.45, p = 0.06 in women). Conversely, in individuals with NGT fasting TG was strongly associated with apo C-III in men (r = 0.83, p < 0.01) but not with FFA, while in women TG was associated with FFA (r = 0.39, p < 0.05) but not with apo C-III. In summary, elevated apo C-III was a predominant factor associated with elevated TG levels in NGT men and all subjects with type 2 diabetes, while FFA were more closely related with TG levels in NGT women.
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Affiliation(s)
- H Flórez
- Instituto de Investigaciones Clínicas, Facultad de Medicina, Universidad del Zulia, Maracaibo, Venezuela
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39
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Ohad N, Yadegari R, Margossian L, Hannon M, Michaeli D, Harada JJ, Goldberg RB, Fischer RL. Mutations in FIE, a WD polycomb group gene, allow endosperm development without fertilization. Plant Cell 1999; 11:407-16. [PMID: 10072400 PMCID: PMC144179 DOI: 10.1105/tpc.11.3.407] [Citation(s) in RCA: 300] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
A fundamental problem in biology is to understand how fertilization initiates reproductive development. Higher plant reproduction is unique because two fertilization events are required for sexual reproduction. First, a sperm must fuse with the egg to form an embryo. A second sperm must then fuse with the adjacent central cell nucleus that replicates to form an endosperm, which is the support tissue required for embryo and/or seedling development. Here, we report cloning of the Arabidopsis FERTILIZATION-INDEPENDENT ENDOSPERM (FIE) gene. The FIE protein is a homolog of the WD motif-containing Polycomb proteins from Drosophila and mammals. These proteins function as repressors of homeotic genes. A female gametophyte with a loss-of-function allele of fie undergoes replication of the central cell nucleus and initiates endosperm development without fertilization. These results suggest that the FIE Polycomb protein functions to suppress a critical aspect of early plant reproduction, namely, endosperm development, until fertilization occurs.
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Affiliation(s)
- N Ohad
- Department of Plant Sciences, Tel Aviv University, Tel Aviv 69978, Israel
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40
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Donahue RP, Zimmet P, Bean JA, Decourten M, DeCarlo Donahue RA, Collier G, Goldberg RB, Prineas RJ, Skyler J, Schneiderman N. Cigarette smoking, alcohol use, and physical activity in relation to serum leptin levels in a multiethnic population: The Miami Community Health Study. Ann Epidemiol 1999; 9:108-13. [PMID: 10037554 DOI: 10.1016/s1047-2797(98)00037-4] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
PURPOSE To examine the correlates of plasma leptin, including fasting insulin, adiposity, and several health habits and behaviors among a nondiabetic multiethnic population. METHODS A cross-sectional study was conducted among 25-44 year old African-Americans (n = 126), Cuban-Americans (n = 107), and non-Hispanic whites (n = 189) randomly selected from Dade County Florida. Fasting leptin levels were correlated with fasting insulin, percent body fat, smoking, alcohol use, and physical activity within each sex. Multiple linear regression and analysis of covariance were used to estimate the independent determinants of plasma leptin concentration separately among men and women. RESULTS Stepwise linear regression analyses revealed statistically significant associations of leptin with percent body fat, fasting insulin, cigarette smoking, and physical activity (both inversely) among men (p < 0.05 for each). Among women, percent body fat, fasting insulin (both positively), cigarette smoking, and alcohol use (inversely) were independent predictors of leptin levels explaining over 70% of the variance. Analyses of covariance revealed that women had higher adjusted mean leptin levels than men (13.1 ng/ml vs. 5.9 ng/ml; p < 0.001), whereas no separate effect of ethnicity was noted. CONCLUSIONS Although adiposity was the strongest correlate of leptin levels, fasting insulin and several health habits and behaviors were independently associated with leptin. After adjustment for these factors, women had significantly higher mean leptin levels than men. The independent association among leptin and insulin levels is intriguing and suggests additional avenues for epidemiologic research.
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Affiliation(s)
- R P Donahue
- SUNY at Buffalo, Department of Social and Preventive Medicine, NY 14214, USA
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Sanders PM, Bui AQ, Weterings K, McIntire KN, Hsu YC, Lee PY, Truong MT, Beals TP, Goldberg RB. Anther developmental defects in Arabidopsis thaliana male-sterile mutants. ACTA ACUST UNITED AC 1999. [DOI: 10.1007/s004970050158] [Citation(s) in RCA: 607] [Impact Index Per Article: 24.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Strange P, Schwartz SL, Graf RJ, Polvino W, Weston I, Marbury TC, Huang WC, Goldberg RB. Pharmacokinetics, pharmacodynamics, and dose-response relationship of repaglinide in type 2 diabetes. Diabetes Technol Ther 1999; 1:247-56. [PMID: 11475269 DOI: 10.1089/152091599317143] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
BACKGROUND The pharmacodynamics and dose-response relationship of repaglinide, a novel oral hypoglycemic agent, were evaluated in steady-state treatment of patients with type 2 diabetes. METHODS Efficacy of repaglinide (0.25 mg, 0.5 mg, 1 mg, 2 mg, and 4 mg) was compared to that of placebo in a double-blind, randomized, parallel-group, 4-week dose-response clinical trial in 143 patients. Repaglinide was administered 15 minutes before meals (breakfast, lunch, and dinner). Efficacy of repaglinide therapy was assessed by measuring changes from baseline in mean levels of blood glucose (BGmean), fasting serum glucose (FSG), and mean levels of serum insulin (INSmean). RESULTS Blood concentrations of repaglinide were proportional to the dose administered. INSmean values increased in all repaglinide treatment groups (by 6.7 to 12.9 microU/mL). All doses of repaglinide significantly decreased values of BGmean and FSG as compared with the placebo group. BGmean values stabilized between the second and third week of repaglinide treatment. A well-defined dose-response relationship was observed for BGmean and FSG values. All doses of repaglinide were well tolerated, and there were no serious adverse events. CONCLUSIONS These findings show that the therapeutic reduction of serum glucose levels produced by repaglinide is dose-dependent for the 0.25- to 4-mg dose range. All doses of repaglinide tested were effective and well tolerated in patients with type 2 diabetes.
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Affiliation(s)
- P Strange
- Novo Nordisk Pharmaceuticals, Inc., Princeton, New Jersey, USA.
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Goldberg RB, Mellies MJ, Sacks FM, Moyé LA, Howard BV, Howard WJ, Davis BR, Cole TG, Pfeffer MA, Braunwald E. Cardiovascular events and their reduction with pravastatin in diabetic and glucose-intolerant myocardial infarction survivors with average cholesterol levels: subgroup analyses in the cholesterol and recurrent events (CARE) trial. The Care Investigators. Circulation 1998; 98:2513-9. [PMID: 9843456 DOI: 10.1161/01.cir.98.23.2513] [Citation(s) in RCA: 577] [Impact Index Per Article: 22.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
BACKGROUND Although diabetes is a major risk factor for coronary heart disease (CHD), little information is available on the effects of lipid lowering in diabetic patients. We determined whether lipid-lowering treatment with pravastatin prevents recurrent cardiovascular events in diabetic patients with CHD and average cholesterol levels. METHODS AND RESULTS The Cholesterol And Recurrent Events (CARE) trial, a 5-year trial that compared the effect of pravastatin and placebo, included 586 patients (14.1%) with clinical diagnoses of diabetes. The participants with diabetes were older, more obese, and more hypertensive. The mean baseline lipid concentrations in the group with diabetes--136 mg/dL LDL cholesterol, 38 mg/dL HDL cholesterol, and 164 mg/dL triglycerides--were similar to those in the nondiabetic group. LDL cholesterol reduction by pravastatin was similar (27% and 28%) in the diabetic and nondiabetic groups, respectively. In the placebo group, the diabetic patients suffered more recurrent coronary events (CHD death, nonfatal myocardial infarction [MI], CABG, and PTCA) than did the nondiabetic patients (37% versus 25%). Pravastatin treatment reduced the absolute risk of coronary events for the diabetic and nondiabetic patients by 8.1% and 5.2% and the relative risk by 25% (P=0.05) and 23% (P<0.001), respectively. Pravastatin reduced the relative risk for revascularization procedures by 32% (P=0.04) in the diabetic patients. In the 3553 patients who were not diagnosed as diabetic, 342 had impaired fasting glucose at entry defined by the American Diabetes Association as 110 to 125 mg/dL. These nondiabetic patients with impaired fasting glucose had a higher rate of recurrent coronary events than those with normal fasting glucose (eg, 13% versus 10% for nonfatal MI). Recurrence rates tended to be lower in the pravastatin compared with placebo group (eg, -50%, P=0.05 for nonfatal MI). CONCLUSIONS Diabetic patients and nondiabetic patients with impaired fasting glucose are at high risk of recurrent coronary events that can be substantially reduced by pravastatin treatment.
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Affiliation(s)
- R B Goldberg
- University of Miami School of Medicine, Miami, FL, USA
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Goldberg RB, Einhorn D, Lucas CP, Rendell MS, Damsbo P, Huang WC, Strange P, Brodows RG. A randomized placebo-controlled trial of repaglinide in the treatment of type 2 diabetes. Diabetes Care 1998; 21:1897-903. [PMID: 9802740 DOI: 10.2337/diacare.21.11.1897] [Citation(s) in RCA: 85] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
OBJECTIVE The objective of the study was to assess the efficacy and safety of repaglinide compared with placebo in the treatment of patients with type 2 diabetes. RESEARCH DESIGN AND METHODS This was a phase II multicenter, double-blind, placebo-controlled, randomized, dose-adjustment and maintenance trial. After screening and a 2-week washout period, 99 patients were randomized to receive either repaglinide (n = 66) or placebo (n = 33). Patients underwent 6 weeks of dose adjustment followed by 12 weeks of dose maintenance. Fasting and stimulated glycosylated hemoglobin (HbA1c), plasma glucose, insulin, and C-peptide were measured at predetermined intervals. Adverse events and hypoglycemic episodes were recorded. RESULTS From baseline to last visit, mean HbA1c decreased from 8.5 to 7.8% in patients treated with repaglinide and increased from 8.1 to 9.3% in patients receiving placebo, with a statistically significant difference of - 1.7% (P < 0.0001) between treatment groups at the last visit. Mean fasting plasma glucose and postprandial glucose increased in patients receiving placebo and decreased in patients treated with repaglinide, with statistically significant (P < 0.01) differences between groups at the last visit. Concentrations of fasting and postprandial insulin and C-peptide were lower at the last visit compared with baseline for patients treated with placebo and higher for patients treated with repaglinide, and the differences between groups were statistically significant (P < 0.05). Overall, repaglinide was well tolerated. CONCLUSIONS This study demonstrated that repaglinide was safe and efficacious in lowering blood glucose concentrations. In addition to overall improvement in glycemic control noted with repaglinide in both sulfonylurea-treated patients and oral hypoglycemic agent-naive patients, repaglinide had a potent glucose-lowering effect in the postprandial period.
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Affiliation(s)
- R B Goldberg
- Diabetes Research Institute, University of Miami School of Medicine, Florida 33136, USA
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Goldberg RB, Hirsch AM. Lotus corniculatus nodulation specificity is changed by the presence of a soybean lectin gene. Plant Cell 1998; 10:1233-50. [PMID: 9707526 PMCID: PMC144063 DOI: 10.1105/tpc.10.8.1233] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Plant lectins have been implicated as playing an important role in mediating recognition and specificity in the Rhizobium-legume nitrogen-fixing symbiosis. To test this hypothesis, we introduced the soybean lectin gene Le1 either behind its own promoter or behind the cauliflower mosaic virus 35S promoter into Lotus corniculatus, which is nodulated by R. loti. We found that nodulelike outgrowths developed on transgenic L. corniculatus plant roots in response to Bradyrhizobium japonicum, which nodulates soybean and not Lotus spp. Soybean lectin was properly targeted to L. corniculatus root hairs, and although infection threads formed, they aborted in epidermal or hypodermal cells. Mutation of the lectin sugar binding site abolished infection thread formation and nodulation. Incubation of bradyrhizobia in the nodulation (nod) gene-inducing flavonoid genistein increased the number of nodulelike outgrowths on transgenic L. corniculatus roots. Studies of bacterial mutants, however, suggest that a component of the exopolysaccharide surface of B. japonicum, rather than Nod factor, is required for extension of host range to the transgenic L. corniculatus plants.
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Abstract
Type 2 diabetes is a major cause of morbidity and mortality resulting from its microangiopathic and macroangiopathic complications. Current approaches to its management and to the prevention of diabetic complications are difficult to implement effectively, and there is little evidence to date that these approaches are reducing the impact of this disease. The recognition that type 2 diabetes usually has a prolonged prediabetic phase raises the possibility that the emergence of hyperglycemia and the atherosclerotic complications associated with diabetes may be preventable by the institution of early treatment modalities. Sufficient data suggest that life-style modification or pharmacotherapy directed at improving insulin sensitivity or insulin secretion in subjects with impaired glucose tolerance may reduce progression to diabetes. Two long-term prospective, controlled trials have been initiated to test this hypothesis.
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Affiliation(s)
- R B Goldberg
- Department of Medicine, University of Miami School of Medicine, Florida, USA.
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Lotan T, Ohto M, Yee KM, West MA, Lo R, Kwong RW, Yamagishi K, Fischer RL, Goldberg RB, Harada JJ. Arabidopsis LEAFY COTYLEDON1 is sufficient to induce embryo development in vegetative cells. Cell 1998. [PMID: 9657152 DOI: 10.1016/s0092-8674(00)81463-81464] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/28/2023]
Abstract
The Arabidopsis LEAFY COTYLEDON1 (LEC1) gene is required for the specification of cotyledon identity and the completion of embryo maturation. We isolated the LEC1 gene and showed that it functions at an early developmental stage to maintain embryonic cell fate. The LEC1 gene encodes a transcription factor homolog, the CCAAT box-binding factor HAP3 subunit. LEC1 RNA accumulates only during seed development in embryo cell types and in endosperm tissue. Ectopic postembryonic expression of the LEC1 gene in vegetative cells induces the expression of embryo-specific genes and initiates formation of embryo-like structures. Our results suggest that LEC1 is an important regulator of embryo development that activates the transcription of genes required for both embryo morphogenesis and cellular differentiation.
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Affiliation(s)
- T Lotan
- Division of Biological Sciences, University of California, Davis 95616, USA
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Lotan T, Ohto M, Yee KM, West MA, Lo R, Kwong RW, Yamagishi K, Fischer RL, Goldberg RB, Harada JJ. Arabidopsis LEAFY COTYLEDON1 is sufficient to induce embryo development in vegetative cells. Cell 1998; 93:1195-205. [PMID: 9657152 DOI: 10.1016/s0092-8674(00)81463-4] [Citation(s) in RCA: 592] [Impact Index Per Article: 22.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The Arabidopsis LEAFY COTYLEDON1 (LEC1) gene is required for the specification of cotyledon identity and the completion of embryo maturation. We isolated the LEC1 gene and showed that it functions at an early developmental stage to maintain embryonic cell fate. The LEC1 gene encodes a transcription factor homolog, the CCAAT box-binding factor HAP3 subunit. LEC1 RNA accumulates only during seed development in embryo cell types and in endosperm tissue. Ectopic postembryonic expression of the LEC1 gene in vegetative cells induces the expression of embryo-specific genes and initiates formation of embryo-like structures. Our results suggest that LEC1 is an important regulator of embryo development that activates the transcription of genes required for both embryo morphogenesis and cellular differentiation.
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Affiliation(s)
- T Lotan
- Division of Biological Sciences, University of California, Davis 95616, USA
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Mosher PE, Nash MS, Perry AC, LaPerriere AR, Goldberg RB. Aerobic circuit exercise training: effect on adolescents with well-controlled insulin-dependent diabetes mellitus. Arch Phys Med Rehabil 1998; 79:652-7. [PMID: 9630144 DOI: 10.1016/s0003-9993(98)90039-9] [Citation(s) in RCA: 85] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
OBJECTIVES To test the safety and effects of exercise conditioning on cardiorespiratory fitness, body composition, muscle strength, glucose regulation, and lipid/cholesterol levels. SUBJECTS Ten male adolescents with insulin-dependent diabetes mellitus (IDDM) and 10 adolescent nondiabetic (ND) subjects. DESIGN Pretest, posttest intervention trial with control group. SETTING University-based human performance laboratory. INTERVENTION Mixed endurance and calisthenic/strength activities performed at a rapid pace three times weekly for 12 weeks. RESULTS Only one subject with IDDM experienced hypoglycemia after a single exercise session. Both subject groups improved their cardiorespiratory endurance (p < .05). Lean body mass of IDDM subjects increased by 3.5% (p < .05). Subjects with and without IDDM lowered their percent body fat (p < .05 and .001, respectively). Strength improvement of IDDM subjects ranged from 13.7% (p < .001) to 44.4% (p < .01), depending upon the maneuver. Fasting blood plasma glucose for all subjects was unchanged by training, but glycosylated hemoglobin A1c of IDDM subjects was reduced by .96 percentage point (p < .05). Reductions of HbA1c benefitted subjects exhibiting poor preconditioning glycemic control. Low-density lipoprotein cholesterol was decreased in subjects with IDDM (p < .05), but not total cholesterol or triglycerides. CONCLUSION Adolescents with IDDM undergoing aerobic circuit training improve their cardiorespiratory endurance, muscle strength, lipid profile, and glucose regulation. Aerobic circuit training is safe for properly trained and monitored adolescent diabetics.
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Affiliation(s)
- P E Mosher
- Exercise Science, Health and Leisure Studies Department, University of Tennessee at Chattanooga, USA
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Donahue RP, Prineas RJ, Bean JA, deCarlo Donahue RA, Goldberg RB, Skyler JS, Schneiderman N. The relation of fasting insulin to blood pressure in a multiethnic population: the Miami Community Health Study. Ann Epidemiol 1998; 8:236-44. [PMID: 9590602 DOI: 10.1016/s1047-2797(97)00208-1] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
PURPOSE The aim of this study was to examine the associations among fasting insulin, adiposity, waist girth, and blood pressure among a nondiabetic multiethnic population. METHODS A cross-sectional study was performed among 25-44-year-old African-Americans (n = 159), Cuban-Americans (n = 128), and non-Hispanic whites (n = 207) selected from Dade County, Florida. Fasting insulin levels were correlated with resting blood pressure level within each ethnic group. The separate effects of percentage body fat and waist girth on the association between blood pressure and insulin were analyzed in multiple linear regression and analysis of covariance. RESULTS Fasting insulin was positively associated with systolic (r = 0.26-0.39; P < 0.01) and diastolic blood pressure (r = 0.19-0.30; P = 0.10 to P < 0.001) among women of all ethnic groups and among non-Hispanic white men (r = 0.27; P < 0.05). Stepwise linear regression analyses revealed statistically significant associations between systolic and diastolic blood pressure and fasting insulin level in non-Hispanic whites independent of other covariates, including sex and percentage body fat (P < 0.001). Fasting insulin was also independently and significantly related to systolic blood pressure among African-Americans (P = 0.02). Among Cuban-Americans, sex and percentage body fat were the main correlates of blood pressure level. Analysis of covariance revealed a relationship between insulin and blood pressure that was independent of waist girth among men and women. CONCLUSIONS Fasting insulin level and blood pressure were positively associated among African-Americans and non-Hispanic whites. This association was not entirely due to the common association with percentage body fat or waist girth.
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Affiliation(s)
- R P Donahue
- University of Miami School of Medicine, Department of Epidemiology and Public Health, FL, USA
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