1
|
Garmes HM. Special features on insulin resistance, metabolic syndrome and vascular complications in hypopituitary patients. Rev Endocr Metab Disord 2024; 25:489-504. [PMID: 38270844 DOI: 10.1007/s11154-023-09872-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 12/28/2023] [Indexed: 01/26/2024]
Abstract
Pituitary hormone deficiency, hypopituitarism, is a dysfunction resulting from numerous etiologies, which can be complete or partial, and is therefore heterogeneous. This heterogeneity makes it difficult to interpret the results of scientific studies with these patients.Adequate treatment of etiologies and up-to-date hormone replacement have improved morbidity and mortality rates in patients with hypopituitarism. As GH replacement is not performed in a reasonable proportion of patients, especially in some countries, it is essential to understand the known consequences of GH replacement in each subgroup of patients with this heterogeneous dysfunction.In this review on hypopituitarism, we will address some particularities regarding insulin resistance, which is no longer common in these patients with hormone replacement therapy based on current guidelines, metabolic syndrome and its relationship with changes in BMI and body composition, and to vascular complications that need to be prevented taking into account the individual characteristics of each case to reduce mortality rates in these patients.
Collapse
Affiliation(s)
- Heraldo M Garmes
- Endocrinology Division, Department of Clinical Medicine, Faculdade de Ciências Médicas, Departamento de Clínica Médica, Disciplina de Endocrinologia, Universidade Estadual de Campinas. Rua Tessália Vieira de Camargo, 126, Barão Geraldo, CEP 13083-887, Campinas, São Paulo, Brasil.
| |
Collapse
|
2
|
Scarano E, Riccio E, Somma T, Arianna R, Romano F, Di Benedetto E, de Alteriis G, Colao A, Di Somma C. Impact of Long-Term Growth Hormone Replacement Therapy on Metabolic and Cardiovascular Parameters in Adult Growth Hormone Deficiency: Comparison Between Adult and Elderly Patients. Front Endocrinol (Lausanne) 2021; 12:635983. [PMID: 33716985 PMCID: PMC7947790 DOI: 10.3389/fendo.2021.635983] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Accepted: 01/14/2021] [Indexed: 11/13/2022] Open
Abstract
Growth hormone deficiency (GHD) in adults is due to a reduced growth hormone (GH) secretion by the anterior pituitary gland which leads to a well-known syndrome characterized by decreased cognitive function and quality of life (QoL), decreased bone mineral density (BMD), increased central adiposity with a reduction in lean body mass, decreased exercise tolerance, hyperlipidemia and increased predisposition to atherogenesis. Considering some similar features between aging and GHD, it was thought that the relative GH insufficiency of the elderly person could make an important contribution to the fragility of elderly. GH stimulation tests are able to differentiate GHD in elderly patients (EGHD) from the physiological reduction of GH secretion that occurs with aging. Although there is no evidence that rhGH replacement therapy increases the risk of developing Diabetes Mellitus (DM), reducing insulin sensitivity and inducing cardiac hypertrophy, long-term monitoring is, however, also mandatory in terms of glucose metabolism and cardiovascular measurements. In our experience comparing the impact of seven years of rhGH treatment on metabolic and cardiovascular parameters in GHD patients divided in two groups [adult (AGHD) and elderly (EGHD) GHD patients], effects on body composition are evident especially in AGHD, but not in EGHD patients. The improvements in lipid profile were sustained in all groups of patients, and they had a lower prevalence of dyslipidemia than the general population. The effects on glucose metabolism were conflicting, but approximately unchanged. The risk of DM type 2 is, however, probably increased in obese GHD adults with impaired glucose homeostasis at baseline, but the prevalence of DM in GHD is like that of the general population. The increases in glucose levels, BMI, and SBP in GHD negatively affected the prevalence of Metabolic Syndrome (MS) in the long term, especially in AGHD patients. Our results are in accordance to other long-term studies in which the effects on body composition and lipid profile are prominent.
Collapse
Affiliation(s)
- Elisabetta Scarano
- Dipartimento di Medicina Clinica e Chirurgia, Sezione di Endocrinologia, Università degli Studi di Napoli Federico II, Naples, Italy
| | - Enrico Riccio
- Dipartimento di Medicina Clinica e Chirurgia, Sezione di Endocrinologia, Università degli Studi di Napoli Federico II, Naples, Italy
| | - Teresa Somma
- Dipartimento di Neuroscienze e Scienze Riproduttive e Odontostomatologiche, Divisione di Neurochirurgia, Università degli Studi di Napoli Federico II, Naples, Italy
| | - Rossana Arianna
- Dipartimento di Medicina Clinica e Chirurgia, Sezione di Endocrinologia, Università degli Studi di Napoli Federico II, Naples, Italy
| | - Fiammetta Romano
- Dipartimento di Medicina Clinica e Chirurgia, Sezione di Endocrinologia, Università degli Studi di Napoli Federico II, Naples, Italy
| | - Elea Di Benedetto
- Dipartimento di Medicina Clinica e Chirurgia, Sezione di Endocrinologia, Università degli Studi di Napoli Federico II, Naples, Italy
| | - Giulia de Alteriis
- Dipartimento di Medicina Clinica e Chirurgia, Sezione di Endocrinologia, Università degli Studi di Napoli Federico II, Naples, Italy
| | - Annamaria Colao
- Dipartimento di Medicina Clinica e Chirurgia, Sezione di Endocrinologia, Università degli Studi di Napoli Federico II, Naples, Italy
| | - Carolina Di Somma
- Dipartimento di Medicina Clinica e Chirurgia, Sezione di Endocrinologia, Università degli Studi di Napoli Federico II, Naples, Italy
| |
Collapse
|
3
|
Kim SH, Park MJ. Effects of growth hormone on glucose metabolism and insulin resistance in human. Ann Pediatr Endocrinol Metab 2017; 22:145-152. [PMID: 29025199 PMCID: PMC5642081 DOI: 10.6065/apem.2017.22.3.145] [Citation(s) in RCA: 84] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/31/2017] [Accepted: 09/11/2017] [Indexed: 01/02/2023] Open
Abstract
Growth hormone (GH) is important for promotion of somatic growth and the regulation of substrate metabolism. Metabolic action of GH occurs in multiple tissues including the liver, muscle, fat and pancreas either directly or indirectly through insulin-like growth factor 1. The diabetogenic action of GH has been well-described in previous in vivo studies. In this paper, we review the metabolic effects of GH on peripheral tissues focusing on glucose metabolism and insulin resistance, and discuss results from human studies on the long-term effects of GH administration on insulin resistance and hyperglycemia.
Collapse
Affiliation(s)
| | - Mi-Jung Park
- Address for correspondence: Mi-Jung Park, MD, PhD http://orcid.org/0000-0002-7202-500X Department of Pediatrics, Inje University Sanggye Paik Hospital, 1342 Dongilro, Nowon-gu, Seoul 01767, Korea Tel: +82-2-950-8826 Fax: +82-2-950-1246 E-mail:
| |
Collapse
|
4
|
Ciresi A, Radellini S, Guarnotta V, Giordano C. The visceral adiposity index is associated with insulin sensitivity and IGF-I levels in adults with growth hormone deficiency. Endocrine 2017; 56:579-588. [PMID: 27520559 DOI: 10.1007/s12020-016-1076-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/23/2016] [Accepted: 07/31/2016] [Indexed: 01/09/2023]
Abstract
The visceral adiposity index, based on anthropometric and metabolic parameters, has been shown to be related to adipose tissue function and insulin sensitivity. We aimed to evaluate the performance of the visceral adiposity index in adult patients with growth hormone deficiency. We enrolled 52 patients(mean age 51 ± 13 years) with newly diagnosed growth hormone deficiency and 50 matched healthy subjects as controls at baseline. At baseline and after 12 and 24 months of treatment we evaluated anthropometric measures, lipid profile, glucose and insulin during an oral glucose tolerance test, hemoglobin A1c, homeostasis model assessment estimate of insulin resistance, quantitative insulin sensitivity check index, insulin sensitivity index Matsuda, insulin-like growth factor-I and visceral adiposity index. At baseline growth hormone deficiency patients showed higher waist circumference (p < 0.001), low-density lipoprotein cholesterol (p < 0.001) and visceral adiposity index (p = 0.003) with lower insulin sensitivity index (p = 0.007) and high-density lipoprotein cholesterol (p = 0.001) than controls. During growth hormone treatment we observed a significant increase in insulin-like growth factor-I (p < 0.001), high-density lipoprotein (p < 0.001) with a trend toward increase in insulin sensitivity index (p = 0.055) and a significant decrease in total cholesterol (p < 0.001) and visceral adiposity index (p < 0.001), while no significant changes were observed in other clinical and metabolic parameters. The visceral adiposity index was the only parameter that significantly correlated with growth hormone peak at diagnosis (p < 0.001) and with insulin-like growth factor-I and insulin sensitivity index both at diagnosis (p = 0.009 and p < 0.001) and after 12 (p = 0.026 and p = 0.001) and 24 months (p < 0.001 and p = 0.001) of treatment. The visceral adiposity index, which has shown to be associated with both insulin-like growth factor-I and insulin sensitivity, proved to be the most reliable index of metabolic perturbation, among the most common indexes of adiposity assessment and a marker of benefit during treatment in adult growth hormone deficiency patients.
Collapse
Affiliation(s)
- Alessandro Ciresi
- Section of Cardio-Respiratory and Endocrine-Metabolic Diseases, Biomedical Department of Internal and Specialist Medicine (DIBIMIS), University of Palermo, Piazza delle Cliniche 2, Palermo, 90127, Italy
| | - Stefano Radellini
- Section of Cardio-Respiratory and Endocrine-Metabolic Diseases, Biomedical Department of Internal and Specialist Medicine (DIBIMIS), University of Palermo, Piazza delle Cliniche 2, Palermo, 90127, Italy
| | - Valentina Guarnotta
- Section of Cardio-Respiratory and Endocrine-Metabolic Diseases, Biomedical Department of Internal and Specialist Medicine (DIBIMIS), University of Palermo, Piazza delle Cliniche 2, Palermo, 90127, Italy
| | - Carla Giordano
- Section of Cardio-Respiratory and Endocrine-Metabolic Diseases, Biomedical Department of Internal and Specialist Medicine (DIBIMIS), University of Palermo, Piazza delle Cliniche 2, Palermo, 90127, Italy.
| |
Collapse
|
5
|
Giovannini L, Tirabassi G, Muscogiuri G, Di Somma C, Colao A, Balercia G. Impact of adult growth hormone deficiency on metabolic profile and cardiovascular risk [Review]. Endocr J 2015; 62:1037-48. [PMID: 26300280 DOI: 10.1507/endocrj.ej15-0337] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Adult growth hormone deficiency (GHD) is a well defined clinical condition, which is characterized by abnormal body composition, impaired physical activity and decreased quality of life. In addition, in recent years, growing interest has been shown towards cardiovascular risks in adult patients affected by GHD. In this regard, GHD is widely known to be associated with increased mortality, likely due to the increase of risk factors, such as central obesity, impaired lipid and glucose profiles and other less-known risk factors, such as inflammatory cytokines, endothelial dysfunction and oxidative stress. However, very few papers have recently discussed this topic. In this review, the aim is to clarify this issue by discussing evidence regarding the effects of adult GHD on metabolic and cardiovascular profiles.
Collapse
Affiliation(s)
- Lara Giovannini
- Division of Endocrinology, Department of Clinical and Molecular Sciences, Umberto I Hospital, School of Medicine, Polytechnic University of Marche, Ancona, Italy
| | | | | | | | | | | |
Collapse
|
6
|
Yuen KCJ, Roberts CT, Frystyk J, Rooney WD, Pollaro JR, Klopfenstein BJ, Purnell JQ. Short-term, low-dose GH therapy improves insulin sensitivity without modifying cortisol metabolism and ectopic fat accumulation in adults with GH deficiency. J Clin Endocrinol Metab 2014; 99:E1862-9. [PMID: 25013996 PMCID: PMC4184063 DOI: 10.1210/jc.2014-1532] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CONTEXT Low-dose GH (LGH) therapy has been reported to improve insulin sensitivity in GH-deficient adults; however, the mechanism is unclear. HYPOTHESIS Effects of LGH therapy on insulin sensitivity are mediated through changes in cortisol metabolism and ectopic fat accumulation. DESIGN AND SETTING This was a double-blind, placebo-controlled, parallel, 3-month study. PARTICIPANTS AND INTERVENTION Seventeen GH-deficient adults were randomized to receive either daily LGH or placebo injections. Fasting blood samples were collected at baseline, and months 1 and 3, whereas hyperinsulinemic-euglycemic clamps, magnetic resonance spectroscopy scans, 24-hour cortisol production rates (CPRs), and sc abdominal fat biopsies were performed at baseline and month 3. MAIN OUTCOME MEASURES Clamp glucose infusion rate, intramyocellular, extramyocellular, and intrahepatic lipid content, 24-hour CPRs, adipocyte size, and adipocyte 11β-hydroxysteroid dehydrogenase activity in adults with GH deficiency were evaluated. RESULTS At month 1, LGH did not alter fasting levels of glucose, insulin, C-peptide, free fatty acid, adiponectin, total IGF-1, IGF-1 bioactivity, IGF-2, IGF binding protein (IGFBP)-2, or IGF-1 to IGFBP-3 molar ratio. At month 3, LGH increased clamp glucose infusion rates (P < .01) and IGF-1 to IGFBP-3 molar ratio (P < .05), but fasting glucose, insulin, C-peptide, free fatty acid, adiponectin, IGF-1 bioactivity, IGF-2, IGFBP-2, 24-hour CPRs, adipocyte size, adipocyte 11β-hydroxysteroid dehydrogenase activity, intrahepatic lipid, extramyocellular, or intramyocellular were unchanged. In the placebo group, all within-group parameters from months 1 and 3 compared with baseline were unchanged. CONCLUSIONS Short-term LGH therapy improves insulin sensitivity without inducing basal lipolysis and had no effect on cortisol metabolism and ectopic fat accumulation in GH-deficient adults. This may reflect an LGH-induced increase in IGF-1 to IGFBP-3 molar ratio exerting insulin-like effects through the abundant muscle IGF-1 receptors, but this hypothesis requires confirmation with further studies.
Collapse
Affiliation(s)
- Kevin C J Yuen
- Division of Endocrinology, Diabetes, and Clinical Nutrition (K.C.J.Y., C.T.R., B.J.K., J.Q.P.), Department of Medicine, and Advanced Imaging Research Center (W.D.R., J.R.P.), Oregon Health and Science University, Portland, Oregon 97239; Oregon National Primate Research Center (C.T.R.), Beaverton, Oregon 97006; and Institute of Clinical Medicine N (J.F.), Aarhus University, DK-8000 Aarhus, Denmark
| | | | | | | | | | | | | |
Collapse
|
7
|
Claessen KMJA, Appelman-Dijkstra NM, Pereira AM, Joustra SD, de Mutsert R, Gast KB, den Heijer M, Smit JWA, Dekkers OM, Biermasz NR. Abnormal metabolic phenotype in middle-aged GH-deficient adults despite long-term recombinant human GH replacement. Eur J Endocrinol 2014; 170:263-72. [PMID: 24217935 DOI: 10.1530/eje-13-0764] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
BACKGROUND Adult GH deficiency (GHD) is associated with increased cardiovascular mortality. Recombinant human GH (rhGH) replacement has beneficial short-term metabolic effects. Although these positive effects sustain during longer follow-up, the prevalence of the metabolic syndrome (MS) remains increased in comparison with population data not adjusted for the higher mean BMI in GHD adults. OBJECTIVE To explore whether middle-aged patients with proposed physiological rhGH replacement have been normalized with respect to MS and its individual components in comparison with the general population, adjusted for age, sex, and BMI. METHODS One hundred and sixty-one GHD patients (aged 40-70 years) were studied before the start and after 5 years of rhGH replacement, and were compared with 1671 subjects (aged 45-66 years) from the general population (NEO Study). RESULTS MS PROPORTION IN GHD PATIENTS WAS 41.0% BEFORE THE START OF RHGH SUPPLETION, INCREASING TO 53.4% AFTER 5 YEARS (P=0.007). DESPITE CHRONIC RHGH REPLACEMENT, GHD PATIENTS HAD A 1.3-TIMES HIGHER MS PROPORTION THAN THE GENERAL POPULATION, INDEPENDENTLY OF AGE, SEX, AND BMI (95% CI 1.11.5, P=0.008). THE GHD POPULATION SHOWED A DIFFERENT METABOLIC PROFILE THAN THE GENERAL POPULATION WITH SIMILAR BMI: an increased risk of hypertriglyceridemia (adjusted prevalence ratio (PR) 2.0, 95% CI 1.7-2.3) and low HDL-C (adjusted PR 1.8, 95% CI 1.5-2.2), but less hyperglycemia (adjusted PR 0.5, 95% CI 0.4-0.7). CONCLUSIONS Despite 5 years of rhGH replacement, GHD patients still have a different metabolic profile and more frequently MS than the general population. These differences were independent of BMI, and resemble the unfavorable metabolic profile of untreated GHD patients, pointing to question the long-term benefits of rhGH replacement.
Collapse
Affiliation(s)
- K M J A Claessen
- Department of Endocrinology and Metabolic Diseases C7-Q and Center for Endocrine Tumors, Leiden University Medical Center, PO Box 9600, 2300 RC Leiden, The Netherlands
| | | | | | | | | | | | | | | | | | | |
Collapse
|
8
|
Appelman-Dijkstra NM, Claessen KMJA, Roelfsema F, Pereira AM, Biermasz NR. Long-term effects of recombinant human GH replacement in adults with GH deficiency: a systematic review. Eur J Endocrinol 2013; 169:R1-14. [PMID: 23572082 DOI: 10.1530/eje-12-1088] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
BACKGROUND The beneficial effects of recombinant human GH (rhGH) therapy in GH deficient (GHD) adults are well-established in the short term. However, data documenting the effects during prolonged follow-up are relatively scarce. OBJECTIVE To evaluate the reported effects of rhGH replacement (≥5 years) in GHD adults on biochemical and anthropometric parameters, quality of life (QoL), bone metabolism, muscle strength, serious adverse events and mortality. METHODS We conducted a systematic literature search. Quality assessment of retrieved papers was performed using a quality assessment based on the modified STROBE statement. RESULTS We included 23 prospective studies with a rhGH treatment duration ranging from 5 to 15 years. Overall, beneficial effects were reported on QoL, body composition, lipid profile, carotid intima media thickness and bone mineral density. In contrast, the prevalence of the metabolic syndrome, glucose levels, BMI and muscle strength were not, or negatively, influenced. Most of the studies were uncontrolled, lacked the presence of a control group (of non-treated GHD patients), and reported no data on lipid-lowering and anti-diabetic medication. Overall mortality was not increased. CONCLUSION rhGH treatment in adult GHD patients is well-tolerated and positively affects QoL in the long term. However, the metabolic and cardiovascular effects during long-term treatment are variable. The low numbers of long-term studies and studied patients and lack of control data hamper definite statements on the efficacy of prolonged treatment. Therefore continuous monitoring of the effects of rhGH replacement to enable an adequate risk-benefit analysis that may justify prolonged, potentially life-long, treatment is advisable.
Collapse
Affiliation(s)
- Natasha M Appelman-Dijkstra
- Department of Endocrinology and Metabolic Diseases C4-R and Center for Endocrine Tumors, Leiden University Medical Center, P.O. Box 9600, 2300 RC Leiden, The Netherlands.
| | | | | | | | | |
Collapse
|
9
|
Roemmler J, Gockel A, Otto B, Bidlingmaier M, Schopohl J. Effects on metabolic variables after 12-month treatment with a new once-a-week sustained-release recombinant growth hormone (GH: LB03002) in patients with GH deficiency. Clin Endocrinol (Oxf) 2012; 76:88-95. [PMID: 21682757 DOI: 10.1111/j.1365-2265.2011.04146.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
INTRODUCTION GH substitution in GH deficiency (GHD) must be subcutaneously administered daily. A new sustained-release formulation of GH (LB03002) has been developed, which has to be injected once a week. As a substudy to the phase III study, we performed this prospective study to evaluate the influence of LB03002 on metabolic variables and hormones. METHODS Eleven patients with GHD [four women/seven men, 58 years (29-69 years)] without GH therapy were included in the study. Eight patients were treated with LB03002 for 12 months and three patients received placebo for 6 months followed by LB03002 for 6 months. A 3-h oral glucose tolerance test (OGTT) was performed at study entry and at study end. Additionally, IGF-I, cholesterol, LDL, HDL, triglycerides, leptin, ghrelin, HbA1c and C-peptide were measured. Body composition was evaluated by dual-energy X-ray absorptiometry (DXA), and waist/hip ratio (WHR) and waist/height (WHtR) ratio were measured by tape and scale. RESULTS Multiple of upper limit of normal (xULN) of IGF-I (0·23 (0·09-0·4) vs 0·71 (0·4-1·04), P < 0·01), WHR (0·98 (0·86-1·04) vs 1·01 (0·86-1·05), P < 0·05) and ghrelin levels [119·8 ng/l (67·7-266·6) vs 137 ng/l (67-289·5), P < 0·05] were significantly higher, whereas fat mass (FM) [34·7% (20·4-49·2) vs 32·4% (16·7-48·5), P < 0·05] and leptin [11·2 μg/l (3·3-55·7) vs 7·05 μg/l (2·4-54·3), P < 0·05] were significantly lower at study end. Glucose, insulin, HOMA-IR, ISI, HOMA-β, C-peptide and HbA1c during OGTT were not significantly different before and after GH substitution, neither were BMI, WHtR, bone mineral density and lipid variables. CONCLUSION Substitution with LB03002 showed statistically significant reduction in FM, which reduces leptin levels and increases ghrelin levels but does not seem to influence glucose and lipid metabolism.
Collapse
Affiliation(s)
- J Roemmler
- Department of Internal Medicine (Endocrinology)-Innenstadt, University of Munich, Germany.
| | | | | | | | | |
Collapse
|
10
|
Wang KS, Lu CY, Chang SH. Evaluation of acute toxicity and teratogenic effects of plant growth regulators by Daphnia magna embryo assay. JOURNAL OF HAZARDOUS MATERIALS 2011; 190:520-528. [PMID: 21514995 DOI: 10.1016/j.jhazmat.2011.03.068] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2011] [Revised: 03/14/2011] [Accepted: 03/21/2011] [Indexed: 05/30/2023]
Abstract
This study selected common plant growth regulators (Atonik, Cytokinin, Ethephon, Gibberellic acid and Paclobutrazol) to investigate their biological toxicity to the waters of the important biological indicator Daphnia magna. The methods used in this study included traditional neonate acute toxicity test, new Daphnia embryo toxicity test, and teratogenic embryo test. The study concluded that the acute toxicity of the five PGRs to Daphnia neonate had EC(50) value range of 1.9-130.5 mg l(-1), while acute toxicity of PGRs on Daphnia embryo had EC(50) value range of 0.2-125 mg l(-1); the Daphnia embryos' LOEC values (0.05-48 mg l(-1)) for the five PGRs were lower than embryo EC(50) values. The toxic ratios of 48 h EC(50) (neonate)/48 h LOEC (embryo) for 5 PGRs were 19-512 times. The study found that teratogenic effects of Paclobutrazol and Cytokinin induced in embryo were higher than those of most other PGRs. Microscopic observation of the teratogenic effects showed that all 5 PGRs induced malformations of the second antenna, rostrum, Malpighian tube, sensory bristles, and tail spine as well as function loss and death.
Collapse
Affiliation(s)
- Kai-Sung Wang
- School of Public Health, Chung Shan Medical University, Taichung 402, Taiwan, ROC.
| | | | | |
Collapse
|