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Guarnotta V, Amodei R, Frasca F, Aversa A, Giordano C. Impact of Chemical Endocrine Disruptors and Hormone Modulators on the Endocrine System. Int J Mol Sci 2022; 23:ijms23105710. [PMID: 35628520 PMCID: PMC9145289 DOI: 10.3390/ijms23105710] [Citation(s) in RCA: 27] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Revised: 05/14/2022] [Accepted: 05/17/2022] [Indexed: 11/16/2022] Open
Abstract
There is growing concern regarding the health and safety issues of endocrine-disrupting chemicals (EDCs). Long-term exposure to EDCs has alarming adverse health effects through both hormone-direct and hormone-indirect pathways. Non-chemical agents, including physical agents such as artificial light, radiation, temperature, and stress exposure, are currently poorly investigated, even though they can seriously affect the endocrine system, by modulation of hormonal action. Several mechanisms have been suggested to explain the interference of EDCs with hormonal activity. However, difficulty in quantifying the exposure, low standardization of studies, and the presence of confounding factors do not allow the establishment of a causal relationship between endocrine disorders and exposure to specific toxic agents. In this review, we focus on recent findings on the effects of EDCs and hormone system modulators on the endocrine system, including the thyroid, parathyroid glands, adrenal steroidogenesis, beta-cell function, and male and female reproductive function.
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Affiliation(s)
- Valentina Guarnotta
- Department of Health Promotion, Mother and Child Care, Internal Medicine and Medical Specialties “G. D’Alessandro” (PROMISE), Section of Endocrinology, University of Palermo, Piazza delle Cliniche 2, 90127 Palermo, Italy; (V.G.); (R.A.)
| | - Roberta Amodei
- Department of Health Promotion, Mother and Child Care, Internal Medicine and Medical Specialties “G. D’Alessandro” (PROMISE), Section of Endocrinology, University of Palermo, Piazza delle Cliniche 2, 90127 Palermo, Italy; (V.G.); (R.A.)
| | - Francesco Frasca
- Endocrinology Section, Department of Clinical and Experimental Medicine, Garibaldi Nesima Hospital, University of Catania, 95122 Catania, Italy;
| | - Antonio Aversa
- Department of Experimental and Clinical Medicine, Section of Endocrinology, Magna Graecia University of Catanzaro, 88100 Catanzaro, Italy;
| | - Carla Giordano
- Department of Health Promotion, Mother and Child Care, Internal Medicine and Medical Specialties “G. D’Alessandro” (PROMISE), Section of Endocrinology, University of Palermo, Piazza delle Cliniche 2, 90127 Palermo, Italy; (V.G.); (R.A.)
- Correspondence: ; Tel.: +39-0916552110
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Zhang C, Zeng Q, Liu Y, Qin Z, Liu L, Tao J, Zhang L, Yang Q, Lei J, Tang X, Wang Q, Zheng L, Hong F. Family History of Hypertension and Cobalt Exposure Synergistically Promote the Prevalence of Hypertension. Biol Trace Elem Res 2022; 200:943-952. [PMID: 33846928 DOI: 10.1007/s12011-021-02707-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/20/2020] [Accepted: 04/02/2021] [Indexed: 12/28/2022]
Abstract
It has been previously reported that family history of hypertension (FHH) and exposure to metals are each independent risk factor for hypertension, but the interaction between the two in relation to hypertension risk has been poorly studied. The object of this study is Dong ethnic group in Guizhou, China. The impacts of exposure to metals and FHH on hypertension incidence were examined by using the restrictive cubic spline (RCS) model as well as the multivariate logistic regression model. As a result, FHH, together with cobalt and lead exposure, was identified to show independent significant correlation with hypertension incidence (P < 0.05). The risk of hypertension increased with the increase in lead and cobalt exposure quartiles. Typically, the RCS model revealed such dose-response relation. To further confirm the association of cobalt, lead, and FHH with the risk of hypertension, multiplication and addition models were used to analyze the influence of the interactions between these variables on the risk of hypertension. The results showed that there was a multiplying interaction between the influence of the FHH and cobalt on the risk of hypertension. As for the additive interaction between cobalt and FHH, the relative excess risk due to interaction (RERI) was determined to be 0.596 (95% Cl: 0.001-1.191), the attributable proportion due to interaction (AP) was calculated as 0.256 (95% Cl: 0.075-0.437), whereas the synergy index (S) was identified to be 1.814 (95% Cl: 1.080-3.047). Our study provides some limited evidence that a FHH and cobalt exposure synergistically promote the prevalence of hypertension.
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Affiliation(s)
- Cailiang Zhang
- School of Public Health, The Key Laboratory of Environmental Pollution Monitoring and Disease Control, Ministry of Education, Guizhou Medical University, Guiyang, 550025, Guizhou, China
| | - Qibing Zeng
- School of Public Health, The Key Laboratory of Environmental Pollution Monitoring and Disease Control, Ministry of Education, Guizhou Medical University, Guiyang, 550025, Guizhou, China
| | - Yalan Liu
- School of Public Health, The Key Laboratory of Environmental Pollution Monitoring and Disease Control, Ministry of Education, Guizhou Medical University, Guiyang, 550025, Guizhou, China
| | - Zixiu Qin
- School of Public Health, The Key Laboratory of Environmental Pollution Monitoring and Disease Control, Ministry of Education, Guizhou Medical University, Guiyang, 550025, Guizhou, China
| | - Leilei Liu
- School of Public Health, The Key Laboratory of Environmental Pollution Monitoring and Disease Control, Ministry of Education, Guizhou Medical University, Guiyang, 550025, Guizhou, China
| | - Junyan Tao
- School of Public Health, The Key Laboratory of Environmental Pollution Monitoring and Disease Control, Ministry of Education, Guizhou Medical University, Guiyang, 550025, Guizhou, China
| | - Linyuan Zhang
- School of Public Health, The Key Laboratory of Environmental Pollution Monitoring and Disease Control, Ministry of Education, Guizhou Medical University, Guiyang, 550025, Guizhou, China
| | - Qianyuan Yang
- School of Public Health, The Key Laboratory of Environmental Pollution Monitoring and Disease Control, Ministry of Education, Guizhou Medical University, Guiyang, 550025, Guizhou, China
| | - Juan Lei
- Guiyang City Center for Disease Control and Prevention, Guiyang, 550003, Guizhou, China
| | - Xuejie Tang
- University Town Hospital, Gui'an New District, Guiyang, 550025, Guizhou, China
| | - Qiaorong Wang
- University Town Hospital, Gui'an New District, Guiyang, 550025, Guizhou, China
| | - Liubo Zheng
- Guizhou Provincial People's Hospital, Guiyang, 550002, Guizhou, China
| | - Feng Hong
- School of Public Health, The Key Laboratory of Environmental Pollution Monitoring and Disease Control, Ministry of Education, Guizhou Medical University, Guiyang, 550025, Guizhou, China.
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Fevrier-Paul A, Soyibo AK, De Silva N, Mitchell S, Nwokocha C, Voutchkov M. Addressing the Challenge of Potentially Hazardous Elements in the Reduction of Hypertension, Diabetes and Chronic Kidney Disease in the Caribbean. J Health Pollut 2021; 11:210613. [PMID: 34268000 PMCID: PMC8276730 DOI: 10.5696/2156-9614-11.30.210613] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Accepted: 04/16/2021] [Indexed: 06/13/2023]
Abstract
BACKGROUND Environmental surveys have characterized trace elements such as lead (Pb), cadmium (Cd) and arsenic (As) as potential risk factors for non-communicable diseases. There have been few studies conducted in the Caribbean region to explore, define or clarify such findings locally. Furthermore, local pollution control efforts are often juxtaposed against more seemingly immediate economic concerns in poor communities. OBJECTIVES The present commentary is a call to action for the evaluation of potentially hazardous elements as potential risk indicators and/or factors of common noncommunicable diseases in the Caribbean. DISCUSSION Findings from Jamaican studies have identified exposure to potentially hazardous elements (PHE) via water, food, and other anthropogenic activities to the detriment of the resident population. Several attempts have been made to abate toxic metal exposure in children with relative success. However, high levels of PHE have been noted in vulnerable populations such as patients with hypertension, diabetes mellitus and chronic kidney disease. Currently, there is low priority towards infrastructure building within the Caribbean region that would promote and sustain long term monitoring and better inform environmental polices impacting chronic diseases. CONCLUSIONS Further investigations are needed to clarify the role that PHE play in increasing the risk or progression of non-communicable diseases, especially in vulnerable groups. COMPETING INTERESTS The authors declare no competing financial interests.
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Affiliation(s)
- Adwalia Fevrier-Paul
- Department of Physics, Faculty of Science and Technology, University of the West Indies, Mona, Jamaica
| | - Adedamola K. Soyibo
- Department of Medicine, University Hospital of the West Indies, Kingston, Jamaica
| | - Nimal De Silva
- Earth and Environmental Sciences, University of Ottawa, Ottawa, ON, Canada
| | - Sylvia Mitchell
- The Biotechnology Centre, Faculty of Science and Technology, University of the West Indies, Mona , Jamaica
| | - Chukwuemeka Nwokocha
- Department of Basic Medical Sciences, The University of the West Indies, Mona, Jamaica
| | - Mitko Voutchkov
- Department of Physics, Faculty of Science and Technology, University of the West Indies, Mona, Jamaica
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Dewanjee S, Sahu R, Karmakar S, Gangopadhyay M. Toxic effects of lead exposure in Wistar rats: involvement of oxidative stress and the beneficial role of edible jute (Corchorus olitorius) leaves. Food Chem Toxicol 2013; 55:78-91. [PMID: 23291325 DOI: 10.1016/j.fct.2012.12.040] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2012] [Revised: 12/20/2012] [Accepted: 12/23/2012] [Indexed: 11/17/2022]
Abstract
Lead (Pb) is considered to be a multi-target toxicant. The present study was undertaken to evaluate the protective effect of aqueous extract of Corchorus olitorius leaves against Pb-acetate induced toxic manifestation in blood, liver, kidney, brain and heart of Wistar rats. The Pb-acetate (5mg/kg body weight) treated rats exhibited a significant inhibition of co-enzymes Q, antioxidant enzymes and reduced glutathione levels in the tissues. In addition, the extent of lipid peroxidation, DNA fragmentation and haematological parameters were significantly altered in the Pb-acetate treated rats as compared to control. Simultaneous administration of test extract (25, 50 and 100mg/kg body weight), could significantly restore the biochemical and haematological parameters near to the normal status through antioxidant activity and/or by preventing bioaccumulation of Pb within the tissues of experimental rats. Presence of substantial quantity of phenolics and flavonoids in the extract may be responsible for the observed protective role against Pb-intoxication.
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Affiliation(s)
- Saikat Dewanjee
- Advanced Pharmacognosy Research Laboratory, Department of Pharmaceutical Technology, Jadavpur University, 188 Raja S. C. Mullick Road, Kolkata 700 032, India.
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Krieg EF, Feng HA. The relationships between blood lead levels and serum follicle stimulating hormone and luteinizing hormone in the National Health and Nutrition Examination Survey 1999-2002. Reprod Toxicol 2011; 32:277-85. [PMID: 21669282 DOI: 10.1016/j.reprotox.2011.05.012] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2010] [Revised: 03/31/2011] [Accepted: 05/20/2011] [Indexed: 10/18/2022]
Abstract
The relationships between blood lead levels and serum follicle stimulating hormone and luteinizing hormone were assessed in a nationally representative sample of women, 35-60 years old, from the National Health and Nutrition Examination Survey 1999-2002. The blood lead levels of the women ranged from 0.2 to 17.0 μg/dL. The estimated geometric mean was 1.4 μg/dL, and the estimated arithmetic mean was 1.6 μg/dL. As the blood lead level increased, the concentration of serum follicle stimulating hormone increased in post-menopausal women, women who had both ovaries removed, and pre-menopausal women. The concentration of luteinizing hormone increased as blood lead level increased in post-menopausal women and women who had both ovaries removed. The lowest concentrations of blood lead at which a relationship was detected were 0.9 μg/dL for follicle stimulating hormone and 3.2 μg/dL for luteinizing hormone. Lead may act directly or indirectly at ovarian and non-ovarian sites to increase the concentrations of follicle stimulating hormone and luteinizing hormone.
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Affiliation(s)
- Edward F Krieg
- National Institute for Occupational Safety and Health, Robert A. Taft Laboratories, 4676 Columbia Parkway, MS C-22, Cincinnati, OH 45226, USA.
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Fiorim J, Ribeiro Júnior RF, Silveira EA, Padilha AS, Vescovi MVA, de Jesus HC, Stefanon I, Salaices M, Vassallo DV. Low-level lead exposure increases systolic arterial pressure and endothelium-derived vasodilator factors in rat aortas. PLoS One 2011; 6:e17117. [PMID: 21364929 PMCID: PMC3045404 DOI: 10.1371/journal.pone.0017117] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2010] [Accepted: 01/21/2011] [Indexed: 11/18/2022] Open
Abstract
Chronic lead exposure induces hypertension and alters endothelial function. However, treatment with low lead concentrations was not yet explored. We analyzed the effects of 7 day exposure to low lead concentrations on endothelium-dependent responses. Wistar rats were treated with lead (1st dose 4 µg/100 g, subsequent dose 0.05 µg/100 g, i.m. to cover daily loss) or vehicle; blood levels attained at the end of treatment were 9.98 µg/dL. Lead treatment had the following effects: increase in systolic blood pressure (SBP); reduction of contractile response to phenylephrine (1 nM–100 µM) of aortic rings; unaffected relaxation induced by acetylcholine (0.1 nM–300 µM) or sodium nitroprusside (0.01 nM–0.3 µM). Endothelium removal, NG-nitro-L-arginine methyl ester (100 µM) and tetraethylammonium (2 mM) increased the response to phenylephrine in treated rats more than in untreated rats. Aminoguanidine (50 µM) increased but losartan (10 µM) and enalapril (10 µM) reduced the response to phenylephrine in treated rats. Lead treatment also increased aortic Na+/K+-ATPase functional activity, plasma angiotensin-converting enzyme (ACE) activity, protein expression of the Na+/K+-ATPase alpha-1 subunit, phosphorylated endothelial nitric oxide synthase (p-eNOS), and inducible nitric oxide synthase (iNOS). Our results suggest that on initial stages of lead exposure, increased SBP is caused by the increase in plasma ACE activity. This effect is accompanied by increased p-eNOS, iNOS protein expression and Na+/K+-ATPase functional activity. These factors might be a compensatory mechanism to the increase in SBP.
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Affiliation(s)
- Jonaina Fiorim
- Department of Physiological Sciences, Federal University of Espirito Santo, Vitoria, Espírito Santo, Brazil
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Abstract
Considering the wide range of chemicals known to disrupt adrenal function and the physiological importance of the adrenal cortex, it is surprising that endocrine disruption of the adrenal gland has not been more widely researched. The chemical nature of adrenal disruptors is highly varied, and there are features of the adrenal structure and function, which render it particularly vulnerable to toxic attack. However, the homeostatic mechanisms inherent in the hypothalamo-pituitary-adrenal axis mean that only the most catastrophic effects are recognized as adrenal disruption, such as in the case of etomidate. In order to detect potentially significant but milder forms of toxic disruption of adrenal function a new approach is needed; this requires the use of more sophisticated approaches than simply measuring one hormone at one time point. New methodologies are also needed, such as the use of human adrenal cell lines for the screening of toxins and for mechanistic investigation of adrenal disruptors. This review focuses on mechanisms of adrenal toxicity and on the challenges facing researchers in this important field.
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Affiliation(s)
- J P Hinson
- Centre for Endocrinology, WHRI, Barts and the London Queen Mary School of Medicine and Dentistry, First Floor John Vane Science Centre, Charterhouse Square, London EC1M 6BQ, UK.
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Glenn BS, Stewart WF, Links JM, Todd AC, Schwartz BS. The longitudinal association of lead with blood pressure. Epidemiology 2003; 14:30-6. [PMID: 12500043 DOI: 10.1097/00001648-200301000-00011] [Citation(s) in RCA: 90] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Several investigators have reported an association of blood lead or bone lead with increased blood pressure and hypertension, but questions remain concerning whether these effects are acute or chronic in nature. METHODS In this longitudinal study, we evaluated the relation of lead, measured in blood and tibia, to changes in blood pressure between 1994 and 1998. We studied 496 current and former employees of a chemical-manufacturing facility in the eastern United States who had previous occupational exposure to inorganic and organic lead. Cohort members who provided three or four blood pressure measurements during the study were included. RESULTS Mean age at baseline was 55.8 years with a mean of 18 years since last occupational exposure to lead. Blood lead at baseline averaged 4.6 microg/dL (standard deviation [SD] = 2.6) or 0.22 micromole/Liter (SD = 0.13). Tibia lead at year three averaged 14.7-microg/gm (SD = 9.4) bone mineral. Change in systolic blood pressure during the study was associated with lead dose, with an average annual increase of 0.64 mmHg (standard error [SE] = 0.25), 0.73 mmHg (SE = 0.26), and 0.61 mmHg (SE = 0.27) for every standard deviation increase in blood lead at baseline, tibia lead at year three, or peak past tibia lead, respectively. CONCLUSIONS The results support an etiologic role for lead in the elevation of systolic blood pressure among adult males and are consistent with both acute and chronic modes of action.
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Affiliation(s)
- Barbara S Glenn
- Kennedy Krieger Institute, Department of Neurology, Johns Hopkins School of Hygiene and Public Health, Baltimore, MD 21205, USA
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Goodfriend TL, Ball DL, Raff H, Bruder ED, Gardner HW, Spiteller G. Oxidized products of linoleic acid stimulate adrenal steroidogenesis. Endocr Res 2002; 28:325-30. [PMID: 12530633 DOI: 10.1081/erc-120016804] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Adrenal steroidogenesis is under complex control, and clinical observations suggest that not all regulators have been identified. We postulated that fatty acid oxidation products found in the diet or formed in the body could affect steroidogenesis. Linoleic acid is a prominent constituent of animal fat and is readily oxidized. We found that several products of linoleic acid oxidation affect production of aldosterone and corticosterone by isolated cells from rat adrenals. We characterized one linoleic acid derivative by gas chromatography/mass spectrometry. It is 12,13-epoxy-9-oxo-10(trans)-octadecenoic acid ("EKODE"). At concentrations between 1 and 30 microM, EKODE stimulated production of aldosterone by zona glomerulosa cells, but at concentrations above 50 microM, it was inhibitory. In zona fasciculata cells, EKODE stimulated corticosterone production at concentrations of 5 microM or greater, and there was no evidence of inhibition at high concentrations. Stimulation of steroidogenesis was observed after 15 min of incubation and continued for at least 2 hrs. The potential relevance of our findings to the hypertension of obesity is discussed.
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Affiliation(s)
- T L Goodfriend
- Wm. S. Middleton Memorial Veterans Hospital, Madison, WI 53705, USA.
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Goodfriend TL, Ball DL, Gardner HW. An oxidized derivative of linoleic acid affects aldosterone secretion by adrenal cells in vitro. Prostaglandins Leukot Essent Fatty Acids 2002; 67:163-7. [PMID: 12324236 DOI: 10.1054/plef.2002.0414] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Based on the clinical observation that humans with visceral adiposity have higher plasma aldosterone levels than controls, we postulated that endogenous fatty acids can be oxidized by the liver to form stimuli of the adrenal cortex. Although we could show that hepatocytes produced adrenal stimuli from linoleic acid in vitro, the yield was very small. To facilitate the elucidation of chemical structures, we incubated a large amount of linoleic acid with lipoxygenase, then treated the hydroperoxide with cysteine and iron. The major product of this process was 12,13-epoxy-9-keto-10-trans-octadecenoic acid. This epoxy-keto compound stimulated aldosterone production at concentrations from 0.5 to 15 microm. At higher concentrations, it was inhibitory. The epoxy-keto-octadecenoic acid exhibited the chromatographic characteristics of one product of the incubation of linoleic acid with hepatocytes. The results are consistent with the postulated conversion of linoleic acid to stimuli of aldosterone production. This may be a mechanistic link between visceral obesity and hypertension in humans.
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Affiliation(s)
- T L Goodfriend
- Research Service, Veterans Hospital, Madison, WI 53705, USA.
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Lai CC, Lin HH, Chen CW, Chen SH, Chiu TH. Excitatory action of lead on rat sympathetic preganglionic neurons in vitro and in vivo. Life Sci 2002; 71:1035-45. [PMID: 12088763 DOI: 10.1016/s0024-3205(02)01789-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Lead exposure elicited an increase in blood pressure and was considered to be a cardiovascular risk factor. The involvements of sympathetic nervous system and circulating catecholamines have been implicated in lead-induced hypertension. This study examined the effects of PbCl(2) on sympathetic preganglionic neurons (SPNs) in vitro and in vivo. In vitro electrophysiological study showed that superfusion of a low concentration (5 microM) of PbCl(2), which had no effects on membrane potential and spontaneous discharge rate, enhanced excitatory postsynaptic potentials (EPSPs) in some of the SPNs examined but inhibited inhibitory postsynaptic potentials (IPSPs) in other SPNs tested. A higher concentration (50 microM) of PbCl(2) inhibited both EPSPs and IPSPs in all SPNs examined. In vivo study showed that intrathecal injection of PbCl(2) (10 and 100 nmol) via an implanted cannula to the T7-T9 segments of urethane-anesthetized rats increased both the heart rate and mean arterial pressure. The pressor and tachycardic responses of intrathecal PbCl(2) (100 nmol) were attenuated by pretreatment with intravenous administration of hexamethonium (10 mg/kg) or intrathecal AP-5 (DL-2-amino-5-phosphonovaleric acid, 100 nmol), but were not significantly antagonized by prior intrathecal administration of CNQX (6-cyano-7-nitroquinoxaline-2,3-dione, 100 nmol). Taken together, these results demonstrated that lead may exert a stimulatory effect on SPNs, which may result from the enhancement of EPSPs and inhibition of IPSPs by low concentrations of lead.
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Affiliation(s)
- Chih Chia Lai
- Department of Pharmacology, Tzu Chi University, 701, Section 3, Chung-Yang Road, 970, Hualien, Taiwan.
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Ganguly A. Aldosterone. Compr Physiol 2000. [DOI: 10.1002/cphy.cp070305] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Schwartz BS, Stewart WF. Different associations of blood lead, meso 2,3-dimercaptosuccinic acid (DMSA)-chelatable lead, and tibial lead levels with blood pressure in 543 former organolead manufacturing workers. ARCHIVES OF ENVIRONMENTAL HEALTH 2000; 55:85-92. [PMID: 10821507 DOI: 10.1080/00039890009603392] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
In this study, the authors' objective was to determine the influence of blood lead, meso 2,3-dimercaptosuccinic acid (DMSA)-chelatable lead, and tibial lead on systolic and diastolic blood pressures and on hypertension in 543 former organolead manufacturing workers. All workers had past exposure to inorganic and organic lead. The authors used linear regression to model systolic and diastolic blood pressure separately, and logistic regression was used for the modeling of hypertension status (i.e., systolic blood pressure > 160 mm Hg, diastolic blood pressure > or =96 mm Hg, or current use of antihypertensive medications). Blood lead, DMSA-chelatable lead, and tibial lead levels had means (standard deviations appear within parentheses) of 4.6 microg/dl (2.6 microg/dl), 19.3 microg (17.2 microg), and 14.4 microg/g (9.3 microg/g), respectively. The authors adjusted for covariates, and they found that blood lead was a predictor of (1) both systolic and diastolic blood pressures and (2) hypertension status in men < 58 y of age. DMSA-chelatable lead and tibial lead were not associated with any of the blood pressure measures. Systolic blood pressure was elevated by blood lead levels as low as 5 microg/dl. We speculate that lead may have a transient influence on blood pressure that is related to target dose levels obtained once release of lead from body stores has occurred.
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Affiliation(s)
- B S Schwartz
- Department of Environmental Health Sciences, Johns Hopkins School of Hygiene and Public Health, Baltimore, Maryland 21205, USA
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Goodfriend TL, Egan BM, Kelley DE. Plasma aldosterone, plasma lipoproteins, obesity and insulin resistance in humans. Prostaglandins Leukot Essent Fatty Acids 1999; 60:401-5. [PMID: 10471129 DOI: 10.1016/s0952-3278(99)80020-9] [Citation(s) in RCA: 80] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Aldosterone production in vitro can be affected by many hormones, autacoids, ions, and lipids, but regulation in humans is incompletely understood. We measured plasma aldosterone in adult subjects with a wide range of obesity and insulin resistance. Aldosterone levels correlated with measures of visceral obesity in one predominantly male cohort and in the women of a second cohort. In the same subjects, aldosterone correlated with insulin resistance. Aldosterone also correlated with plasma cortisol in men and women, and with DHEA-S in women. The data suggested that visceral fat stimulates adrenal steroidogenesis. We found that certain fatty acids stimulated aldosterone production in vitro by rat adrenal cells incubated with rat hepatocytes, but not adrenal cells alone. The results suggested that fatty acids from visceral adipocytes induce hepatic formation of an adrenal secretagogue. This may explain the correlation of plasma steroids with visceral obesity. Aldosterone may contribute to vascular diseases that complicate obesity.
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Affiliation(s)
- T L Goodfriend
- William S. Middleton Memorial Veterans Hospital, Madison, WI 53705, USA.
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Abstract
Plasma aldosterone levels were measured in adults whose body mass index ranged from lean to obese. Blood was drawn while subjects rested supine for 30-90 minutes. Aldosterone was higher in obese subjects, but could not be explained by renin or K+. The best predictors of plasma aldosterone were abdominal obesity measured as waist/hip ratio or by CT scan, and insulin resistance measured by insulin or oral glucose tolerance tests, or euglycemic clamp. In one cohort, these correlations were limited to women; in the other, they were also found in men. In the women with a strong correlation between aldosterone and visceral fat, aldosterone also correlated with cortisol and DHEA-S. The data are consistent with an effect of visceral fat on adrenal steroidogenesis. Visceral adipocytes have a high rate of triglyceride turnover, and their circulation drains directly to the liver. In an experiment based on these characteristics, rat hepatocytes responded to fatty acids by releasing an unidentified secretagogue that stimulated aldosterone production by rat adrenal glomerulosa cells. The clinical data suggest that aldosterone participates in hypertension associated with the "Insulin Resistance Syndrome". The adrenal in viscerally obese subjects may be driven by a secretagogue released from the liver by fatty acids from abdominal adipocytes.
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Affiliation(s)
- T L Goodfriend
- William S. Middleton Memorial Veterans Hospital, and Department of Medicine, University of Wisconsin, Madison, USA
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