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Kotzki S, Savina Y, Bouvet R, Gil H, Blaise S, Cracowski JL, Roustit M. Iontophoresis of treprostinil promotes wound healing in a murine model of scleroderma-related ulcers. Rheumatology (Oxford) 2021; 61:2704-2708. [PMID: 34888615 DOI: 10.1093/rheumatology/keab852] [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: 07/14/2021] [Revised: 11/06/2021] [Indexed: 11/13/2022] Open
Abstract
OBJECTIVE Systemic Sclerosis (SSc) is a rare, chronic disease characterized by fibrosis, vascular alterations and digital ulcerations. Few drugs have shown efficacy to enhance wound healing of existing SSc-related ulcers. Local delivery of treprostinil, a prostacyclin analogue, may improve wound healing. The present work aimed first at developing a mouse model of SSc-related ulcerations and second at assessing the effect of iontophoresis of treprostinil on wound healing. METHODS We used two murine models of SSc: chemically-induced with HOCl, and Urokinase-type plasminogen activator receptor (uPAR)-deficient. Excisional wounding was performed on the dorsal midline with a biopsy punch. Animals were randomized into three groups: treated with electrostimulation alone, with treprostinil iontophoresis, or untreated. We assessed wound healing over time, as well as skin microvascular reactivity, inflammation, microvessel density, and collagen distribution, before wounding and after re-epithelialization. RESULTS uPAR-/- mice, but not HOCl-treated mice, showed impaired wound healing and decreased microvascular reactivity compared with their controls. Treprostinil iontophoresis improved wound healing and microvascular density and decreased inflammation in uPAR-/- mice, while electro-stimulation did not. However, treprostinil had no effect on microvascular reactivity and collagen distribution. CONCLUSION This study suggests that excisional wounds in uPAR-/- mice are a relevant model of SSc-related ulcers. In addition, treprostinil iontophoresis enhances wound healing in this model. Further work in now needed to show whether this effect translates in humans.
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Affiliation(s)
- Sylvain Kotzki
- Univ. Grenoble Alpes, Inserm, UMR1300, HP2, 38000, France .Grenoble.,Grenoble-Alpes University Hospital, Grenoble, 38043, France
| | - Yann Savina
- Univ. Grenoble Alpes, Inserm, UMR1300, HP2, 38000, France .Grenoble
| | - Raphael Bouvet
- Univ. Grenoble Alpes, Inserm, UMR1300, HP2, 38000, France .Grenoble
| | - Hugo Gil
- Grenoble-Alpes University Hospital, Grenoble, 38043, France
| | - Sophie Blaise
- Univ. Grenoble Alpes, Inserm, UMR1300, HP2, 38000, France .Grenoble.,Grenoble-Alpes University Hospital, Grenoble, 38043, France
| | - Jean-Luc Cracowski
- Univ. Grenoble Alpes, Inserm, UMR1300, HP2, 38000, France .Grenoble.,Grenoble-Alpes University Hospital, Grenoble, 38043, France
| | - Matthieu Roustit
- Univ. Grenoble Alpes, Inserm, UMR1300, HP2, 38000, France .Grenoble.,Grenoble-Alpes University Hospital, Grenoble, 38043, France
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Alghadir A, Miraj M, Ali S. Efficacy of Curcumin with Iontophoretic Application on Paw Edema and Hematological Responses in Collagen-Induced Arthritis Rat Models. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE : ECAM 2020; 2020:4606520. [PMID: 32351596 PMCID: PMC7171674 DOI: 10.1155/2020/4606520] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Revised: 01/21/2020] [Accepted: 02/14/2020] [Indexed: 11/17/2022]
Abstract
BACKGROUND According to previous studies, oral administration of curcumin elucidates anti-inflammatory effect irrespective of its poor bioavailability. This study aims to measure the efficacy of lyophilized curcumin extracts with iontophoresis in arthritic rat models. METHODS Lyophilization and characterization of curcumin using the standard HPTLC method was carried out followed by induction of inflammatory arthritis in male albino rats. The animals were then treated with curcumin in three different forms, i.e., oral curcumin (OCU), oral curcumin with topical application (OCU + TOCU), and oral curcumin along with iontophoretically applied curcumin (OCU + IOCU). Various objective variables including body weight, paw edema, arthritic scores, and hematological and biochemical parameters, as well as histopathological examinations were conducted. RESULTS All the curcumin-treated groups showed significant alleviation of arthritic condition (p ∗ < 0.05) when compared with arthritic controls. Group V (OCU + IOCU) demonstrated maximum therapeutic effect by restoring the body weight, decreasing the paw edema, and normalizing the Erythrocyte sedimentation rate and leukocyte count, when compared with other experimental rat groups (p ∗∗ < 0.01). CONCLUSIONS Iontophoretic administration of curcumin may ameliorate arthritic symptoms significantly, and the effect is assumed to be due to better penetration and enhanced bioavailability. Geriatrics patients are supposed to be benefited fairly by this technique.
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Affiliation(s)
- Ahmad Alghadir
- Rehabilitation Research Chair, College of Applied Medical Sciences, King Saud University, Riyadh, Saudi Arabia
| | - Mohammad Miraj
- Rehabilitation Research Chair, College of Applied Medical Sciences, King Saud University, Riyadh, Saudi Arabia
| | - Sharique Ali
- Department of Biotechnology, Saifia Science College, Bhopal, India
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Guigui A, Mazet R, Blaise S, Cracowski C, Beau-Guillaumot M, Kotzki S, Roustit M, Cracowski JL. Treprostinil Hydrogel Iontophoresis in Systemic Sclerosis-Related Digital Skin Ulcers: A Safety Study. J Clin Pharmacol 2020; 60:758-767. [PMID: 32080862 DOI: 10.1002/jcph.1574] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Accepted: 12/02/2019] [Indexed: 12/19/2022]
Abstract
Digital skin ulcers are a severe complication of systemic sclerosis. The first-line treatment is intravenous iloprost, but it induces dose-limiting adverse effects. Local administration of treprostinil through skin iontophoresis may be a safe alternative. We conducted a 2-stage, randomized, placebo-controlled single-ascending-dose study in healthy volunteers and patients with systemic sclerosis-related digital ulcer. We further explored the effect of the procedure on skin blood flux. In a first group of healthy subjects, treprostinil and placebo iontophoresis were performed at 3 locations (ie, 6 skin sites): the sole of the foot, the leg, and the fingers. We used a 1-mg/mL hydrogel of treprostinil. We then randomly treated systemic sclerosis-related digital ulcers in a 3:1 ratio of treprostinil or placebo. We used concentrations from 0.1 to 1 mg/mL. All adverse events were recorded and rated according to the Common Terminology Criteria for Adverse Events (CTCAE), whereas skin microvascular blood flux was recorded with laser speckle contrast imaging. Among the 12 healthy volunteers, we observed 60 local adverse effects: burns, skin pain, erythema, and pruritus, graded 1 or 2 on the 5-point CTCAE scale. Treprostinil iontophoresis significantly increased skin blood flux on the leg (AUC0-4 h at 88 460% ± 6436% versus 12 730% ± 3397% baseline flux.min respectively; P < .001) and on the sole of the foot (AUC0-3 h at 20 124% ± 6119% versus 3142% ± 3036% baseline flux.min, respectively; P = .018) with a trend on the finger. Among 5 patients with systemic sclerosis-related digital ulcer, 2 resolutive local adverse effects were reported. Iontophoresis of treprostinil hydrogel was safe in systemic sclerosis patients with digital ulcer.
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Affiliation(s)
- Alicia Guigui
- Grenoble Alpes University Hospital, Clinical Pharmacology, Grenoble, France.,Univ. Grenoble Alpes, Grenoble, France
| | - Roseline Mazet
- Grenoble Alpes University Hospital, Pharmacy, Grenoble, France.,Univ. Grenoble Alpes, DPM, UMR CNRS 5063, ICMG FR 2607, Saint Martin d'Hères, France
| | - Sophie Blaise
- Univ. Grenoble Alpes, Grenoble, France.,Grenoble Alpes University Hospital, Department of Vascular Medicine, Grenoble, France
| | - Claire Cracowski
- Grenoble Alpes University Hospital, Clinical Pharmacology, Grenoble, France.,Univ. Grenoble Alpes, Grenoble, France
| | | | | | - Matthieu Roustit
- Grenoble Alpes University Hospital, Clinical Pharmacology, Grenoble, France.,Univ. Grenoble Alpes, Grenoble, France
| | - Jean-Luc Cracowski
- Grenoble Alpes University Hospital, Clinical Pharmacology, Grenoble, France.,Univ. Grenoble Alpes, Grenoble, France
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Teaima MH, Abdelhalim SA, El-Nabarawi MA, Attia DA, Helal DA. Non-ionic surfactant based vesicular drug delivery system for topical delivery of caffeine for treatment of cellulite: design, formulation, characterization, histological anti-cellulite activity, and pharmacokinetic evaluation. Drug Dev Ind Pharm 2017; 44:158-171. [DOI: 10.1080/03639045.2017.1386206] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- Mahmoud H. Teaima
- Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmacy, Cairo University, Cairo, Egypt
| | - Sally A. Abdelhalim
- Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmacy, Cairo University, Cairo, Egypt
| | - Mohamed A. El-Nabarawi
- Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmacy, Cairo University, Cairo, Egypt
| | - Dalia A. Attia
- Department of Pharmaceutics, Faculty of Pharmacy, The British University in Egypt, Cairo, Egypt
| | - Doaa A. Helal
- Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmacy, Elfayoum University, Elfayoum, Egypt
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Pluchart H, Khouri C, Blaise S, Roustit M, Cracowski JL. Targeting the Prostacyclin Pathway: Beyond Pulmonary Arterial Hypertension. Trends Pharmacol Sci 2017; 38:512-523. [DOI: 10.1016/j.tips.2017.03.003] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Revised: 03/03/2017] [Accepted: 03/06/2017] [Indexed: 01/08/2023]
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Gaillard-Bigot F, Roustit M, Jourdil JF, Stanke-Labesque F, Cracowski JL. Vascular Effects of Treprostinil Cutaneous Iontophoresis on the Leg, Finger, and Foot. J Clin Pharmacol 2017; 57:1215-1220. [DOI: 10.1002/jcph.898] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2016] [Accepted: 02/27/2017] [Indexed: 11/10/2022]
Affiliation(s)
- Florence Gaillard-Bigot
- Inserm CIC1406; Clinical Pharmacology Department; Grenoble Alps University Hospital; Grenoble France
| | - Matthieu Roustit
- Inserm CIC1406; Clinical Pharmacology Department; Grenoble Alps University Hospital; Grenoble France
- Inserm HP2; Grenoble France
- Univ. Grenoble-Alpes; Grenoble France
| | | | - Françoise Stanke-Labesque
- Inserm HP2; Grenoble France
- Laboratory of Pharmacology; Grenoble Alps University Hospital; Grenoble France
| | - Jean-Luc Cracowski
- Inserm CIC1406; Clinical Pharmacology Department; Grenoble Alps University Hospital; Grenoble France
- Inserm HP2; Grenoble France
- Univ. Grenoble-Alpes; Grenoble France
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Gaillard-Bigot F, Roustit M, Blaise S, Cracowski C, Seinturier C, Imbert B, Carpentier P, Cracowski JL. Treprostinil Iontophoresis Improves Digital Blood Flow during Local Cooling in Systemic Sclerosis. Microcirculation 2016; 23:266-70. [PMID: 26833587 DOI: 10.1111/micc.12272] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2015] [Accepted: 01/23/2016] [Indexed: 11/30/2022]
Abstract
INTRODUCTION Severe Raynaud's syndrome and DUs are the most prevalent manifestations of SSc peripheral microvascular disease. We tested whether treprostinil iontophoresis on the finger pad of patients with SSc would improve digital blood flow during hand cooling. METHODS Eleven patients with limited cutaneous SSc underwent a double-blinded iontophoresis of treprostinil (2.56 × 10(-4) M during two hours) and placebo (NaCl 0.9%) on two finger pads. Then, the hand was inserted for 30 minutes in a fenestrated cooling box at 8 °C, and skin blood flow was recorded continuously using LSCI. RESULTS During the local cooling, CVC was significantly higher at the treprostinil site than at the placebo site and remained higher 30 minutes after the test. CONCLUSIONS In patients with SSc, digital treprostinil iontophoresis shifts skin blood flow upward during local cooling of the hand and during the initial rewarming phase. Digital treprostinil iontophoresis should now be tested in larger scale studies.
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Affiliation(s)
- Florence Gaillard-Bigot
- University Grenoble Alpes, Grenoble, France.,Clinical Pharmacology Unit, INSERM CIC1406, Grenoble University Hospital, Grenoble, France.,INSERM, U1042, HP2, Grenoble, France
| | - Matthieu Roustit
- University Grenoble Alpes, Grenoble, France.,Clinical Pharmacology Unit, INSERM CIC1406, Grenoble University Hospital, Grenoble, France.,INSERM, U1042, HP2, Grenoble, France
| | - Sophie Blaise
- INSERM, U1042, HP2, Grenoble, France.,Vascular Medicine Department, Grenoble University Hospital, Grenoble, France
| | - Claire Cracowski
- Clinical Pharmacology Unit, INSERM CIC1406, Grenoble University Hospital, Grenoble, France.,INSERM, U1042, HP2, Grenoble, France
| | | | - Bernard Imbert
- Vascular Medicine Department, Grenoble University Hospital, Grenoble, France
| | - Patrick Carpentier
- Vascular Medicine Department, Grenoble University Hospital, Grenoble, France
| | - Jean-Luc Cracowski
- University Grenoble Alpes, Grenoble, France.,Clinical Pharmacology Unit, INSERM CIC1406, Grenoble University Hospital, Grenoble, France.,INSERM, U1042, HP2, Grenoble, France
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Abstract
The stratum corneum continues to pose considerable impediment to transdermal drug delivery. One of the effective ways of circumventing this challenge is through the use of iontophoresis. Iontophoresis uses low-level current to drive charged compounds across the skin. This review discusses progress made in the field of iontophoretic transport of small and large molecules. The major obstacles are also touched upon and advances made in the last few decades described. A number of iontophoretic systems approved for clinical use by regulatory authorities is also discussed.
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Affiliation(s)
- Kevin Ita
- a College of Pharmacy, Touro University , Mare Island-Vallejo , CA , USA
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Hellmann M, Roustit M, Gaillard-Bigot F, Cracowski JL. Cutaneous iontophoresis of treprostinil, a prostacyclin analog, increases microvascular blood flux in diabetic malleolus area. Eur J Pharmacol 2015; 758:123-8. [DOI: 10.1016/j.ejphar.2015.03.066] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Revised: 03/19/2015] [Accepted: 03/25/2015] [Indexed: 12/18/2022]
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Roustit M, Blaise S, Cracowski JL. Trials and tribulations of skin iontophoresis in therapeutics. Br J Clin Pharmacol 2015; 77:63-71. [PMID: 23590287 DOI: 10.1111/bcp.12128] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2013] [Accepted: 04/02/2013] [Indexed: 12/20/2022] Open
Abstract
Iontophoresis is a method of non-invasive transdermal drug delivery based on the transfer of charged molecules using a low-intensity electric current. Both local and systemic administration are possible; however, the skin pharmacokinetics of iontophoretically delivered drugs is complex and difficult to anticipate. The unquestionable theoretical advantages of the technique make it attractive in several potential applications. After a brief review of the factors influencing iontophoresis, we detail the current applications of iontophoresis in therapeutics and the main potential applications under investigation, including systemic and topical drugs and focusing on the treatment of scleroderma-related ulcerations. Finally, we address the issue of safety, which could be a limitation to the routine clinical use of iontophoresis.
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Affiliation(s)
- Matthieu Roustit
- Inserm U1042, Université Joseph Fourier, Grenoble, France; Clinical Pharmacology Unit, Inserm CIC03, Grenoble, France
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Kotzki S, Roustit M, Arnaud C, Godin-Ribuot D, Cracowski JL. Effect of continuous vs pulsed iontophoresis of treprostinil on skin blood flow. Eur J Pharm Sci 2015; 72:21-6. [PMID: 25712367 DOI: 10.1016/j.ejps.2015.02.012] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Revised: 02/11/2015] [Accepted: 02/15/2015] [Indexed: 11/25/2022]
Abstract
INTRODUCTION Systemic sclerosis (SSc) is a rare disease affecting digital microcirculation, leading to finger ulcers and in some cases to amputation. Prostacyclin analogues can be used intravenously but their therapeutic effect is counterbalanced by potentially serious vasodilatation-induced side effects. Iontophoresis of treprostinil could be a promising local therapeutic alternative for SSc-related digital ulcers. Iontophoretic drug delivery is complex, and whether continuous or periodic current should be used remains debated. The objective of the present work is to compare the effect of continuous vs pulsed iontophoresis of treprostinil in rats. MATERIALS AND METHODS Treprostinil (0.64 mM and 0.064 mM) and NaCl were delivered by cathodal iontophoresis onto the hindquarters of anaesthetized rats. Three protocols delivering the same quantity of current were compared: one was continuous (100 μA during 20 min) and two were periodic (B: twenty 1-min cycles with 200 μA during 30 s followed by 30 s Off; and C: twenty 1-min cycles with 600 μA during 10s followed by 50s Off) (n=8 for each protocol with each concentration). Skin blood flow was quantified using laser Doppler imaging and skin resistance was calculated with Ohm's law. RESULTS All protocols induced a significant increase in skin blood flow. At the lower concentration (0.064 mM treprostinil) the pulsed 10/50 sequence significantly enhanced cutaneous blood flow (Table 1; Fig. 1B) compared to continuous iontophoresis or the 30/30 sequence. We noted that the pulsed iontophoresis of NaCl (10/50 sequence) induced a significant early increase in cutaneous blood flow in comparison with continuous iontophoresis. Skin resistance measures were negatively correlated with current intensity delivered. CONCLUSION In conclusion, pulsed iontophoresis of treprostinil with a 10 s/50 s (On/Off) protocol at 600 μA increases the efficacy of iontophoresis at 0.064 mM but not at a tenfold higher concentration. Pulsed iontophoresis could be used to optimize treprostinil iontophoresis, to provide similar efficacy with decreased costs, and should now be tested on humans.
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Affiliation(s)
- Sylvain Kotzki
- Clinical Pharmacology Unit, INSERM CIC1406, Grenoble University Hospital, Grenoble, France; Univ. Grenoble Alpes, Grenoble, France.
| | - Matthieu Roustit
- Clinical Pharmacology Unit, INSERM CIC1406, Grenoble University Hospital, Grenoble, France; UMR 1042-HP2, INSERM, Grenoble, France; Univ. Grenoble Alpes, Grenoble, France
| | - Claire Arnaud
- UMR 1042-HP2, INSERM, Grenoble, France; Univ. Grenoble Alpes, Grenoble, France
| | - Diane Godin-Ribuot
- UMR 1042-HP2, INSERM, Grenoble, France; Univ. Grenoble Alpes, Grenoble, France
| | - Jean-Luc Cracowski
- Clinical Pharmacology Unit, INSERM CIC1406, Grenoble University Hospital, Grenoble, France; UMR 1042-HP2, INSERM, Grenoble, France; Univ. Grenoble Alpes, Grenoble, France
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12
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Cutaneous Iontophoresis of Treprostinil in Systemic Sclerosis: A Proof-of-Concept Study. Clin Pharmacol Ther 2014; 95:439-45. [DOI: 10.1038/clpt.2013.255] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2013] [Accepted: 12/17/2013] [Indexed: 11/09/2022]
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13
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Kotzki S, Roustit M, Arnaud C, Boutonnat J, Blaise S, Godin-Ribuot D, Cracowski JL. Anodal Iontophoresis of a Soluble Guanylate Cyclase Stimulator Induces a Sustained Increase in Skin Blood Flow in Rats. J Pharmacol Exp Ther 2013; 346:424-31. [DOI: 10.1124/jpet.113.205484] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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Blaise S, Roustit M, Hellmann M, Millet C, Cracowski JL. Cathodal Iontophoresis of Treprostinil Induces a Sustained Increase in Cutaneous Blood Flux in Healthy Volunteers. J Clin Pharmacol 2013; 53:58-66. [DOI: 10.1177/0091270011434352] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2011] [Accepted: 11/09/2011] [Indexed: 11/15/2022]
Affiliation(s)
| | | | - Marcin Hellmann
- Clinical Pharmacology Department, Inserm CIC3; University Hospital; Grenoble; France
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Iontophoresis of endothelin receptor antagonists in rats and men. PLoS One 2012; 7:e40792. [PMID: 22808263 PMCID: PMC3396598 DOI: 10.1371/journal.pone.0040792] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2012] [Accepted: 06/13/2012] [Indexed: 11/19/2022] Open
Abstract
Introduction The treatment of scleroderma-related digital ulcers is challenging. The oral endothelin receptor antagonist (ERA) bosentan has been approved but it may induce liver toxicity. The objective of this study was to test whether ERAs bosentan and sitaxentan could be locally delivered using iontophoresis. Methods Cathodal and anodal iontophoresis of bosentan and sitaxentan were performed on anaesthetized rat hindquarters without and during endothelin-1 infusion. Skin blood flow was quantified using laser-Doppler imaging and cutaneous tolerability was assessed. Iontophoresis of sitaxentan (20 min, 20 or 100 µA) was subsequently performed on the forearm skin of healthy men (n = 5). Results In rats neither bosentan nor sitaxentan increased skin blood flux compared to NaCl. When simultaneously infusing endothelin-1, cathodal iontophoresis of sitaxentan increased skin blood flux compared to NaCl (AUC0–20 were 44032.2±12277 and 14957.5±23818.8 %BL.s, respectively; P = 0.01). In humans, sitaxentan did not significantly increase skin blood flux as compared to NaCl. Iontophoresis of ERAs was well tolerated both in animals and humans. Conclusions This study shows that cathodal iontophoresis of sitaxentan but not bosentan partially reverses endothelin-induced skin vasoconstriction in rats, suggesting that sitaxentan diffuses into the dermis. However, sitaxentan does not influence basal skin microvascular tone in rats or in humans.
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