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Khanagar SB, AlBalawi F, Alshehri A, Awawdeh M, Iyer K, Kumar Bijai L, Aldhebaib A, Gokulchandra Singh O. Unveiling the Impact of Electronic Cigarettes (EC) on Health: An Evidence-Based Review of EC as an Alternative to Combustible Cigarettes. Cureus 2024; 16:e56451. [PMID: 38638766 PMCID: PMC11024731 DOI: 10.7759/cureus.56451] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/19/2024] [Indexed: 04/20/2024] Open
Abstract
Cigarette smoking has been considered a major public health concern due to its serious impact on health. However, smokers intending to quit may find long-term abstinence challenging. When smoking an electronic cigarette (EC), users can experience a sensation and taste similar to that of smoking a combustible cigarette. Therefore, manufacturers promote these products as a viable substitute for combustible cigarettes. However, several researchers report the serious health impacts experienced by EC users. Therefore, this review aims to examine the health impacts of EC use. Based on the findings of the research papers reported in the literature, the role of EC as a smoking cessation tool is unclear. Several researchers have also reported a significant association between EC usage among non-smokers at baseline and the future initiation of combustible cigarette smoking. EC use significantly impacts user health. The nicotine that is present in EC e-liquids can elevate blood pressure, resulting in blood vessel constriction and an increase in heart rate, ultimately leading the body to an ischemic condition, resulting in myocardial infarction (MI), stroke, and increased arterial stiffness. Researchers report a higher likelihood of prediabetes among EC users; its usage was associated with higher OR of having asthma attacks and higher OR of reporting depression and has an impact on birth outcomes among pregnant women. Men using EC are more likely to report erectile dysfunction than non-users. EC also has a significant impact on oral health, which includes periodontal diseases, mucosal lesions, irritation in the mouth and throat, reduced salivary flow, and an increased risk of developing cancer. The physical injury resulting from exploding EC is another health concern. The frequently burned areas included the hands, face, genitalia, and thighs. Marketers promote EC as an alternative to combustible cigarettes and a tool for quitting smoking. However, the Food and Drug Administration has not approved them for smoking cessation. EC can have a serious impact on the health of their users; hence, the findings of this paper have several implications, including the need for regulation of the sales and marketing of these products and educating the users on the impact of these products on their health and safety.
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Affiliation(s)
- Sanjeev B Khanagar
- King Abdullah International Medical Research Center, King Saud Bin Abdulaziz University for Health Sciences, Ministry of National Guard Health Affairs, Riyadh, SAU
- Preventive Dental Science Department, College of Dentistry, King Saud Bin Abdulaziz University for Health Sciences, Riyadh, SAU
| | - Farraj AlBalawi
- Preventive Dental Science Department, College of Dentistry, King Saud Bin Abdulaziz University for Health Sciences, Riyadh, SAU
- King Abdullah International Medical Research Center, King Saud Bin Abdulaziz University for Health Sciences, Ministry of National Guard Health Affairs, Riyadh, SAU
| | - Aram Alshehri
- Restorative and Prosthetic Dental Sciences Department, College of Dentistry, King Saud Bin Abdulaziz University for Health Sciences, Riyadh, SAU
- King Abdullah International Medical Research Center, King Saud Bin Abdulaziz University for Health Sciences, Ministry of National Guard Health Affairs, Riyadh, SAU
| | - Mohammed Awawdeh
- Preventive Dental Science Department, College of Dentistry, King Saud Bin Abdulaziz University for Health Sciences, Riyadh, SAU
- King Abdullah International Medical Research Center, King Saud Bin Abdulaziz University for Health Sciences, Ministry of National Guard Health Affairs, Riyadh, SAU
| | - Kiran Iyer
- Preventive Dental Science Department, College of Dentistry, King Saud Bin Abdulaziz University for Health Sciences, Riyadh, SAU
- King Abdullah International Medical Research Center, King Saud Bin Abdulaziz University for Health Sciences, Ministry of National Guard Health Affairs, Riyadh, SAU
| | - Laliytha Kumar Bijai
- Maxillofacial Surgery and Diagnostic Sciences Department, College of Dentistry, King Saud Bin Abdulaziz University for Health Sciences, Riyadh, SAU
- King Abdullah International Medical Research Center, King Saud Bin Abdulaziz University for Health Sciences, Ministry of National Guard Health Affairs, Riyadh, SAU
| | - Ali Aldhebaib
- Radiological Sciences Program, College of Applied Medical Sciences, King Saud Bin Abdulaziz University for Health Sciences, Riyadh, SAU
- King Abdullah International Medical Research Center, King Saud Bin Abdulaziz University for Health Sciences, Ministry of National Guard Health Affairs, Riyadh, SAU
| | - Oinam Gokulchandra Singh
- Radiological Sciences Program, College of Applied Medical Sciences, King Saud Bin Abdulaziz University for Health Sciences, Riyadh, SAU
- King Abdullah International Medical Research Center, King Saud Bin Abdulaziz University for Health Sciences, Ministry of National Guard Health Affairs, Riyadh, SAU
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Seo YS, Park JM, Kim JH, Lee MY. Cigarette Smoke-Induced Reactive Oxygen Species Formation: A Concise Review. Antioxidants (Basel) 2023; 12:1732. [PMID: 37760035 PMCID: PMC10525535 DOI: 10.3390/antiox12091732] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2023] [Revised: 08/28/2023] [Accepted: 09/05/2023] [Indexed: 09/29/2023] Open
Abstract
Smoking is recognized as a significant risk factor for numerous disorders, including cardiovascular diseases, respiratory conditions, and various forms of cancer. While the exact pathogenic mechanisms continue to be explored, the induction of oxidative stress via the production of excess reactive oxygen species (ROS) is widely accepted as a primary molecular event that predisposes individuals to these smoking-related ailments. This review focused on how cigarette smoke (CS) promotes ROS formation rather than the pathophysiological repercussions of ROS and oxidative stress. A comprehensive analysis of existing studies revealed the following key ways through which CS imposes ROS burden on biological systems: (1) ROS, as well as radicals, are intrinsically present in CS, (2) CS constituents generate ROS through chemical reactions with biomolecules, (3) CS stimulates cellular ROS sources to enhance production, and (4) CS disrupts the antioxidant system, aggravating the ROS generation and its functions. While the evidence supporting these mechanisms is chiefly based on in vitro and animal studies, the direct clinical relevance remains to be fully elucidated. Nevertheless, this understanding is fundamental for deciphering molecular events leading to oxidative stress and for developing intervention strategies to counter CS-induced oxidative stress.
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Affiliation(s)
| | | | | | - Moo-Yeol Lee
- BK21 FOUR Team and Integrated Research Institute for Drug Development, College of Pharmacy, Dongguk University, Goyang-si 10326, Gyeonggi-do, Republic of Korea; (Y.-S.S.); (J.-M.P.); (J.-H.K.)
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Marinelli L, Lanfranco F, Motta G, Zavattaro M. Erectile Dysfunction in Men with Chronic Obstructive Pulmonary Disease. J Clin Med 2021; 10:2730. [PMID: 34205713 PMCID: PMC8234796 DOI: 10.3390/jcm10122730] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Revised: 05/27/2021] [Accepted: 06/10/2021] [Indexed: 12/17/2022] Open
Abstract
Erectile dysfunction (ED) seems to be a widespread sexual issue in men affected by chronic obstructive pulmonary disease (COPD). Multiple causes appear to be involved such as hormonal imbalance, smoking habit, chronic inflammation, endothelial dysfunction, chronic hypoxia, psychiatric disorders (depression and anxiety), and medications. ED can have a significant impact on COPD men and consequently on their quality of life, which is usually already compromised. Given this situation, however, pneumologists usually do not properly care for the sexuality of COPD patients especially because men can be reluctant to talk about their intimate issues. The aim of this narrative review is to briefly summarize the evidence emerging from literature and to provide a wide point of view about sexual dysfunction in COPD men.
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Affiliation(s)
- Lorenzo Marinelli
- Division of Endocrinology, Diabetology and Metabolism, Department of Medical Sciences, University of Turin, 10126 Turin, Italy; (L.M.); (G.M.); (M.Z.)
| | - Fabio Lanfranco
- Division of Endocrinology, Andrology and Metabolism, Humanitas Gradenigo, Department of Medical Sciences, University of Turin, 10153 Turin, Italy
| | - Giovanna Motta
- Division of Endocrinology, Diabetology and Metabolism, Department of Medical Sciences, University of Turin, 10126 Turin, Italy; (L.M.); (G.M.); (M.Z.)
| | - Marco Zavattaro
- Division of Endocrinology, Diabetology and Metabolism, Department of Medical Sciences, University of Turin, 10126 Turin, Italy; (L.M.); (G.M.); (M.Z.)
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Pincus J, Sandoval V, Dick B, Sanekommu G, Rajasekaran R, Ramasamy R, Raheem O. E-Cigarette-Associated Endothelial Damage: A Potential Mechanism for Erectile Dysfunction. Sex Med Rev 2021; 10:168-173. [PMID: 33931382 DOI: 10.1016/j.sxmr.2021.01.003] [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: 11/30/2020] [Revised: 01/13/2021] [Accepted: 01/15/2021] [Indexed: 11/17/2022]
Abstract
INTRODUCTION Electronic cigarettes (e-cigs) have increased in popularity as a potentially less harmful alternative to tobacco smoking; however, the literature suggests "vaping" can cause endothelial damage, which can adversely affect erectile function. While there is a known link between smoking cigarettes and erectile dysfunction (ED), the effect of e-cigs on erectile function has been understudied. OBJECTIVES To review the evidence for e-cig use causing endothelial dysfunction, to explore endothelial dysfunction as a potential mechanism for ED, and to determine if there is literature to support e-cigs as a cause of ED. METHODS A literature review was performed to identify publications pertaining to e-cig consumption and ED. Publications regarding e-cig consumption and vascular or endothelial damage were also included. The search was conducted through PubMed, MEDLINE database, the Cochrane Library Central Search, Web of Science, and Google Scholar. We identified 40+ publications for review, including 6 clinical trials and 3 basic science studies. RESULTS The literature suggests that e-cig use induces oxidative stress, including the direct formation of reactive oxygen species and hydroxyl radicals, leading to endothelial damage. Endothelial dysfunction is a potential mechanism for ED, but there is a paucity of studies evaluating the relationship between e-cig use and ED. CONCLUSION E-cig use may cause ED in men, but more studies, specifically clinical trials, are needed to establish a relationship between e-cigs and ED. E-cig-induced endothelial dysfunction is a potential mechanism for ED that is worth exploring further. J Pincus, V Sandoval, B Dick, et al. E-Cigarette-Associated Endothelial Damage: A Potential Mechanism for Erectile Dysfunction. Sex Med Rev 2021;XX:XXX-XXX.
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Affiliation(s)
- Joshua Pincus
- Department of Urology, Tulane University School of Medicine, New Orleans, LA, USA
| | - Victor Sandoval
- Department of Urology, Hospital Valentin Gomez Farias, Zapopan, Mexico
| | - Brian Dick
- Department of Urology, Tulane University School of Medicine, New Orleans, LA, USA
| | - Ganesh Sanekommu
- Department of Urology, Tulane University School of Medicine, New Orleans, LA, USA
| | - Raj Rajasekaran
- Department of Urology, University of California, San Diego School of Medicine, CA, USA
| | - Ranjith Ramasamy
- Department of Urology, University of Miami Miller School of Medicine, FL, USA
| | - Omer Raheem
- Department of Urology, Tulane University School of Medicine, New Orleans, LA, USA.
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Costa ED, Silva JF, Garcia DC, Wainstein AJ, Rezende BA, Tostes RC, Teixeira MM, Cortes SF, Lemos VS. Decreased expression of neuronal nitric oxide synthase contributes to the endothelial dysfunction associated with cigarette smoking in human. Nitric Oxide 2020; 98:20-28. [DOI: 10.1016/j.niox.2020.02.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Revised: 02/01/2020] [Accepted: 02/18/2020] [Indexed: 12/27/2022]
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Pharmacology and perspectives in erectile dysfunction in man. Pharmacol Ther 2020; 208:107493. [PMID: 31991196 DOI: 10.1016/j.pharmthera.2020.107493] [Citation(s) in RCA: 51] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Accepted: 11/05/2019] [Indexed: 12/15/2022]
Abstract
Penile erection is a perfect example of microcirculation modulated by psychological factors and hormonal status. It is the result of a complex neurovascular process that involves the integrative synchronized action of vascular endothelium; smooth muscle; and psychological, neuronal, and hormonal systems. Therefore, the fine coordination of these events is essential to maintain penile flaccidity or allow erection; an alteration of these events leads to erectile dysfunction (ED). ED is defined as the consistent or recurrent inability of a man to attain and/or maintain a penile erection sufficient for sexual activity. A great boost to this research field was given by commercialization of phosphodiesterase-5 (PDE5) inhibitors. Indeed, following the discovery of sildenafil, research on the mechanisms underlying penile erection has had an enormous boost, and many preclinical and clinical papers have been published in the last 10 years. This review is structured to provide an overview of the mediators and peripheral mechanism(s) involved in penile function in men, the drugs used in therapy, and the future prospective in the management of ED. Indeed, 30% of patients affected by ED are classified as "nonresponders," and there is still an unmet need for therapeutic alternatives. A flowchart suggesting the guidelines for ED evaluation and the ED pharmacological treatment is also provided.
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Kovac JR, Labbate C, Ramasamy R, Tang D, Lipshultz LI. Effects of cigarette smoking on erectile dysfunction. Andrologia 2014; 47:1087-92. [PMID: 25557907 DOI: 10.1111/and.12393] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/20/2014] [Indexed: 11/27/2022] Open
Abstract
Cigarette smoking is a leading cause of preventable morbidity and mortality in the United States. Although public policies have resulted in a decreased number of new smokers, smoking rates remain stubbornly high in certain demographics with 20% of all American middle-aged men smoking. In addition to the well-established harmful effects of smoking (i.e. coronary artery disease and lung cancer), the past three decades have led to a compendium of evidence being compiled into the development of a relationship between cigarette smoking and erectile dysfunction. The main physiologic mechanism that appears to be affected includes the nitric oxide signal transduction pathway. This review details the recent literature linking cigarette smoking to erectile dysfunction, epidemiological associations, dose dependency and the effects of smoking cessation on improving erectile quality.
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Affiliation(s)
| | - C Labbate
- Department of Urology and The Center for Reproductive Medicine, Baylor College of Medicine, Houston, TX, USA
| | - R Ramasamy
- Department of Urology and The Center for Reproductive Medicine, Baylor College of Medicine, Houston, TX, USA
| | - D Tang
- Department of Urology and The Center for Reproductive Medicine, Baylor College of Medicine, Houston, TX, USA
| | - L I Lipshultz
- Department of Urology and The Center for Reproductive Medicine, Baylor College of Medicine, Houston, TX, USA
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Harris AC, Stepanov I, Pentel PR, LeSage MG. Delivery of nicotine in an extract of a smokeless tobacco product reduces its reinforcement-attenuating and discriminative stimulus effects in rats. Psychopharmacology (Berl) 2012; 220:565-76. [PMID: 21960181 PMCID: PMC3363290 DOI: 10.1007/s00213-011-2514-y] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/07/2011] [Accepted: 09/12/2011] [Indexed: 12/21/2022]
Abstract
RATIONALE Animal models of tobacco addiction rely on administration of nicotine alone or nicotine combined with isolated constituents. Models using tobacco extracts derived from tobacco products and containing a range of tobacco constituents might more accurately simulate tobacco exposure in humans. OBJECTIVE To compare the effects of nicotine alone and an aqueous smokeless tobacco extract in several addiction-related animal behavioral models. METHODS Nicotine alone and nicotine dose-equivalent concentrations of extract were compared in terms of their acute effects on intracranial self-stimulation (ICSS) thresholds, discriminative stimulus effects, and effects on locomotor activity. RESULTS Similar levels of nicotine and minor alkaloids were achieved using either artificial saliva or saline for extraction, supporting the clinical relevance of the saline extracts used in these studies. Extract produced reinforcement-enhancing (ICSS threshold-decreasing) effects similar to those of nicotine alone at low to moderate nicotine doses, but reduced reinforcement-attenuating (ICSS threshold-increasing) effects at a high nicotine dose. In rats trained to discriminate nicotine alone from saline, intermediate extract doses did not substitute for the training dose as well as nicotine alone. Locomotor stimulant effects and nicotine distribution to brain were similar following administration of extract or nicotine alone. CONCLUSIONS The reinforcement-attenuating and discriminative stimulus effects of nicotine delivered in an extract of a commercial smokeless tobacco product differed from those of nicotine alone. Extracts of tobacco products may be useful for evaluating the abuse liability of those products and understanding the role of non-nicotine constituents in tobacco addiction.
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Affiliation(s)
- Andrew C. Harris
- Minneapolis Medical Research Foundation, Minneapolis, MN, Minneapolis, MN,Department of Medicine, University of Minnesota Medical School
| | | | - Paul R. Pentel
- Minneapolis Medical Research Foundation, Minneapolis, MN, Minneapolis, MN,Department of Medicine, University of Minnesota Medical School,Department of Pharmacology, University of Minnesota
| | - Mark G. LeSage
- Minneapolis Medical Research Foundation, Minneapolis, MN, Minneapolis, MN,Department of Medicine, University of Minnesota Medical School
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Hastrup SG, Chen X, Bechtold JE, Kyle RF, Rahbek O, Keyler DE, Skoett M, Soeballe K. Effect of nicotine and tobacco administration method on the mechanical properties of healing bone following closed fracture. J Orthop Res 2010; 28:1235-9. [PMID: 20225318 DOI: 10.1002/jor.21106] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/20/2009] [Accepted: 12/24/2009] [Indexed: 02/04/2023]
Abstract
We previously showed different effects of tobacco and nicotine on fracture healing, but due to pump reservoir limits, maximum exposure period was 4 weeks. To allow flexibility in pre- and post-fracture exposure periods, the objective of this study was to compare a new oral administration route for nicotine to the established pump method. Four groups were studied: (1) pump saline, (2) pump saline + oral tobacco, (3) pump saline/nicotine + oral tobacco, and (4) pump saline + oral nicotine/tobacco. Sprague-Dawley rats (n = 84) received a transverse femoral fracture stabilized with an intramedullary pin 1 week after initiating dosing. After 3 weeks, no difference was found in torsional strength or stiffness between oral nicotine/tobacco or pump nicotine + tobacco, while energy absorption with oral nicotine/tobacco was greater than pump nicotine + tobacco (p < 0.05). Compared to saline control, strength for oral nicotine/tobacco was higher than control (p < 0.05), and stiffnesses for pump nicotine + tobacco and oral nicotine/tobacco were higher than control (p < 0.05). No differences in energy were found for either nicotine-tobacco group compared to saline control. Mean serum cotinine (stable nicotine metabolite) was different between pump and oral nicotine at 1 and 4 weeks, but all groups were in the range of 1-2 pack/day smokers. In summary, relevant serum cotinine levels can be reached in rats with oral nicotine, and, in the presence of tobacco, nicotine can influence mechanical aspects of fracture healing, dependent on administration method. Caution should be exercised when comparing results of fracture healing studies using different methods of nicotine administration.
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Affiliation(s)
- Sidsel Gaarn Hastrup
- Orthopaedic Research Laboratory, Department of Orthopaedic Surgery, Aarhus University Hospital, Norrebrogade 44, Building 1A, 8000 Aarhus C, Denmark.
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Unverdorben M, von Holt K, Winkelmann BR. Smoking and atherosclerotic cardiovascular disease: part II: role of cigarette smoking in cardiovascular disease development. Biomark Med 2010; 3:617-53. [PMID: 20477529 DOI: 10.2217/bmm.09.51] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Potential mechanisms and biomarkers of atherosclerosis related to cigarette smoking - a modifiable risk factor for that disease - are discussed in this article. These include smoking-associated inflammatory markers, such as leukocytes, high-sensitivity C-reactive protein, serum amyloid A, ICAM-1 and IL-6. Other reviewed markers are indicative for smoking-related impairment of arterial endothelial function (transcapillary leakage of albumin, inhibition of endogenous nitric oxide synthase activity and reduced endothelium-dependent vasodilation) or point to oxidative stress caused by various chemicals (cholesterol oxidation, autoantibodies to oxidized low-density lipoprotein, plasma levels of malondialdehyde and F(2)-isoprostanes and reduced antioxidant capacity). Smoking enhances platelet aggregability, increases blood viscosity and shifts the pro- and antithrombotic balance towards increased coagulability (e.g., fibrinogen, von Willebrand factor, ICAM-1 and P-selectin). Insulin resistance is higher in smokers compared with nonsmokers, and hemoglobin A1c is dose-dependently elevated, as is homocysteine. Smoke exposure may influence the kinetics of markers with different response to transient or chronic changes in cigarette smoking behavior.
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Affiliation(s)
- Martin Unverdorben
- Clinical Research Institute, Center for Cardiovascular Diseases, Heinz-Meise-Strasse 100, 36199 Rotenburg an der Fulda, Germany.
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Venkatakrishnan P, Gairola CG, Castagnoli N, Miller RT. Naphthoquinones and bioactive compounds from tobacco as modulators of neuronal nitric oxide synthase activity. Phytother Res 2009; 23:1663-72. [PMID: 19367663 PMCID: PMC2788052 DOI: 10.1002/ptr.2789] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Studies were conducted with extracts of several varieties of tobacco in search of neuronal nitric oxide synthase (nNOS) inhibitors which may be of value in the treatment of stroke. Current therapies do not directly exploit modulation of nNOS activity due to poor selectivity of the currently available nNOS inhibitors. The properties of a potentially novel nNOS inhibitor(s) derived from tobacco extracts, and the concentration-dependent, modulatory effects of the tobacco-derived naphthoquinone compound, 2,3,6-trimethyl-1,4-naphthoquinone (TMN), on nNOS activity were investigated, using 2-methyl-1,4-naphthoquinone (menadione) as a control. Up to 31 microM, both TMN and menadione stimulated nNOS-catalysed L-citrulline production. However, at higher concentrations of TMN (62.5-500 microM), the stimulation was lost in a concentration-dependent manner. With TMN, the loss of stimulation did not decrease beyond the control activity. With menadione (62.5-500 microM), the loss of stimulation surpassed that of the control (78+/-0.01% of control activity), indicating a true inhibition of nNOS activity. This study suggests that potential nNOS inhibitors are present in tobacco, most of which remain to be identified.
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Affiliation(s)
- Priya Venkatakrishnan
- Department. of Biological Sciences, University of Texas at El Paso, El Paso, TX 79968 USA
| | - C. Gary Gairola
- Graduate Center for Toxicology, University of Kentucky, Lexington, KY 40536 USA
| | - Neal Castagnoli
- Dept. of Chemistry, Virginia Tech., Blacksburg, VA 24061-0212
| | - R. Timothy Miller
- Department. of Biological Sciences, University of Texas at El Paso, El Paso, TX 79968 USA
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Lammer EJ, Iovannisci DM, Tom L, Schultz K, Shaw GM. Gastroschisis: A gene-environment model involving the VEGF-NOS3 pathway. AMERICAN JOURNAL OF MEDICAL GENETICS PART C-SEMINARS IN MEDICAL GENETICS 2008; 148C:213-8. [DOI: 10.1002/ajmg.c.30182] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
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Tostes RC, Carneiro FS, Lee AJ, Giachini FRC, Leite R, Osawa Y, Webb RC. Cigarette smoking and erectile dysfunction: focus on NO bioavailability and ROS generation. J Sex Med 2008; 5:1284-95. [PMID: 18331273 DOI: 10.1111/j.1743-6109.2008.00804.x] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
INTRODUCTION Thirty million men in the United States suffer from erectile dysfunction (ED) and this number is expected to double by 2025. Considered a major public health problem, which seriously affects the quality of life of patients and their partners, ED becomes increasingly prevalent with age and chronic smoking is a major risk factor in the development of ED. AIM To review available evidence concerning the effects of cigarette smoking on vascular changes associated with decreased nitric oxide (NO) bioavailability and increased reactive oxygen species (ROS) generation. METHODS We examined epidemiological and clinical data linking cigarette smoking and ED, and the effects of smoking on vascular NO bioavailability and ROS generation. MAIN OUTCOME MEASURES There are strong parallels between smoking and ED and considerable evidence supporting the concept that smoking-related ED is associated with reduced bioavailability of NO because of increased ROS. RESULTS Cigarette smoking-induced ED in human and animal models is associated with impaired arterial flow to the penis or acute vasospasm of the penile arteries. Long-term smoking produces detrimental effects on the vascular endothelium and peripheral nerves and also causes ultrastructural damage to the corporal tissue, all considered to play a role in chronic smoking-induced ED. Clinical and basic science studies provide strong indirect evidence that smoking may affect penile erection by the impairment of endothelium-dependent smooth muscle relaxation or more specifically by affecting NO production via increased ROS generation. Whether nicotine or other products of cigarette smoke mediate all effects related to vascular damage is still unknown. CONCLUSIONS Smoking prevention represents an important approach for reducing the risk of ED. The characterization of the components of cigarette smoke leading to ED and the mechanisms by which these components alter signaling pathways activated in erectile responses are necessary for a complete comprehension of cigarette smoking-associated ED.
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Affiliation(s)
- Rita C Tostes
- University of Sao Paulo, Department of Pharmacology, Sao Paulo, SP, Brazil.
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Lowe ER, Everett AC, Lau M, Dunbar AY, Michener D, Osawa Y. Naturally occurring neuronal NO-synthase inactivators found in Nicotiana tabacum (Solanaceae) and other plants. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2007; 14:344-52. [PMID: 17084601 DOI: 10.1016/j.phymed.2006.09.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
NO-synthase (NOS) is a heme-containing enzyme that catalyzes the oxidation of L-arginine to nitric oxide, an important cellular signaling molecule. Recently, it was found that aqueous extracts of tobacco cigarettes cause the inactivation of the neuronal isoform of NOS (nNOS) and that this may explain some of the toxicological effects of smoking. Although the exact identity of the chemical inactivator(s) is not known, we wondered if extracts prepared from other plants, including those closely related to tobacco, Nicotiana tabacum (Solanaceae), would similarly inactivate nNOS. We examined 33 plants, representing diverse members of the plant kingdom ranging from whisk fern, Psilotum nudum (Psilotaceae) to tobacco and discovered 18 plants that contain a chemical inactivator(s) of nNOS. Of these plants, 16 are members of the core asterids flowering plant group. Of these asterids, 6 are members of the Solanaceae family, of which tobacco is a member. Based on the phylogenetic relationship of the plants, it is possible that the same chemical or related chemical inactivator(s) exist. This, in turn, may help elucidate the structure of the chemical(s), as well as provide a source of a potentially novel inactivator of nNOS. The alkaloid nicotine can be excluded as putative nNOS inhibitor.
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Affiliation(s)
- Ezra R Lowe
- Department of Pharmacology, The University of Michigan Medical School, 1301 Medical Science Research Building III, Ann Arbor, MI 48109-0632, USA
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Osawa Y, Lau M, Lowe ER. Plant-Derived Small Molecule Inhibitors of Neuronal NO-Synthase: Potential Effects on Protein Degradation. PLANT SIGNALING & BEHAVIOR 2007; 2:129-130. [PMID: 19704759 PMCID: PMC2633918 DOI: 10.4161/psb.2.2.4071] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2007] [Accepted: 02/27/2007] [Indexed: 05/28/2023]
Abstract
Cigarette smoking is known to cause a decrease in NO production in man resulting in a variety of pathological effects, including vascular dysfunction. Aqueous extracts of cigarette and cigarette smoke contain chemical inhibitors to NO-synthases, a heme-containing cytochrome P450 enzymes. More recently, it was shown that freshly harvested leaves from the tobacco plant (Nicotiana tabacum, Solanaceae) also contain chemical inhibitors to neuronal NO-synthase (nNOS). Examination of leaves from 32 other plants representing diverse members of the plant kingdom showed that 17 other plants, besides tobacco, contain these chemical inhibitors. Of all these plants, 16 are members of the core asterids flowering plant group and 6 are members of the Solanaceae family. Although the identity of the chemicals is not known, perhaps the closely related plants contain the same or similar compounds that inhibit nNOS. The inhibitory effects are not attributable to nicotine. The discovery of these chemicals and their further characterization may help to explain the loss of nNOS in smokers. In this addendum, we discuss these results in light of the effect of tobacco-derived chemicals in inhibiting P450 cytochromes, as well as our thoughts on how the inactivation of nNOS leads to its selective downregulation through proteolytic degradation.
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Affiliation(s)
- Yoichi Osawa
- Department of Pharmacology; University of Michigan Medical School; Ann Arbor, Michigan USA
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Zhang WZ, Venardos K, Chin-Dusting J, Kaye DM. Adverse effects of cigarette smoke on NO bioavailability: role of arginine metabolism and oxidative stress. Hypertension 2006; 48:278-85. [PMID: 16801489 DOI: 10.1161/01.hyp.0000231509.27406.42] [Citation(s) in RCA: 121] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Endothelial dysfunction is a hallmark of cardiovascular disease, and the l-arginine:NO pathway plays a critical role in determining endothelial function. Recent studies suggest that smoking, a well-recognized risk factor for vascular disease, may interfere with l-arginine and NO metabolism; however, this remains poorly characterized. Accordingly, we performed a series of complementary in vivo and in vitro studies to elucidate the mechanism by which cigarette smoke adversely affects endothelial function. In current smokers, plasma levels of asymmetrical dimethyl-arginine (ADMA) were 80% higher (P = 0.01) than nonsmokers, whereas citrulline (17%; P < 0.05) and N-hydroxy-l-arginine (34%; P < 0.05) were significantly lower. Exposure to 10% cigarette smoke extract (CSE) significantly affected endothelial arginine metabolism with reductions in the intracellular content of citrulline (81%), N-hydroxy-l-arginine (57%), and arginine (23%), while increasing ADMA (129%). CSE significantly inhibited (38%) arginine uptake in conjunction with a 34% reduction in expression of the arginine transporter, CAT1. In conjunction with these studies, CSE significantly reduced the activity of eNOS and NO production by endothelial cells, while stimulating the production of reactive oxygen species. In conclusion, cigarette smoke adversely affects the endothelial l-arginine NO synthase pathway, resulting in reducing NO production and elevated oxidative stress. In conjunction, exposure to cigarette smoke increases ADMA concentration, the latter being a risk factor for cardiovascular disease.
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Affiliation(s)
- Wei-Zheng Zhang
- Wynn Department of Metabolic Cardiology, Baker Heart Research Institute, PO Box 6492, St Kilda Rd Central, Melbourne, Victoria 8008, Australia
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Lowe ER, Everett AC, Lee AJ, Lau M, Dunbar AY, Berka V, Tsai AL, Osawa Y. Time-dependent inhibition and tetrahydrobiopterin depletion of endothelial nitric-oxide synthase caused by cigarettes. Drug Metab Dispos 2005; 33:131-8. [PMID: 15470159 DOI: 10.1124/dmd.104.001891] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Smoking causes a dysfunction in endothelial nitric-oxide synthase (eNOS), which is ameliorated, in part, by administration of tetrahydrobiopterin (BH(4)). The exact mechanism by which the nitric oxide deficit occurs is unknown. We have previously shown that aqueous extracts of chemicals in cigarettes (CE) cause the suicide inactivation of neuronal NO synthase (nNOS) by interacting at the substrate-binding site. In the current study, we have found that CE directly inactivates eNOS by a process that is not affected by the natural substrate l-arginine and is distinct from the mechanism of inactivation of nNOS. We discovered that CE causes a time-, concentration-, and NADPH-dependent inactivation of eNOS in an in vitro system containing the purified enzyme, indicating a metabolic component to the inactivation. The CE-treated eNOS but not nNOS was nearly fully reactivated upon incubation with excess BH(4), suggesting that BH(4) depletion is a potential mechanism of inactivation. Moreover, in the presence of CE, eNOS catalyzed the oxidation of BH(4) to dihydrobiopterin and biopterin by a process attenuated by high concentrations of superoxide dismutase but not catalase. We speculate that a redox active component in CE, perhaps a quinone compound, causes oxidative uncoupling of eNOS to form superoxide, which in turn oxidizes BH(4). The discovery of a direct inactivation of eNOS by a compound(s) present in tobacco provides a basis not only for further study of the mechanisms responsible for the biological effects of tobacco but also a search for a potentially novel inactivator of eNOS.
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Affiliation(s)
- Ezra R Lowe
- Department of Pharmacology, University of Michigan Medical School, 1301 Medical Science Research Building III, Ann Arbor, MI 48109-0632, USA
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