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1.
EBioMedicine ; 33: 282-288, 2018 Jul.
Article in English | MEDLINE | ID: mdl-29983350

ABSTRACT

BACKGROUND: Dupuytren's disease is a common fibrotic condition of the hand that causes irreversible flexion contractures of the fingers, with no approved therapy for early stage disease. Our previous analysis of surgically-excised tissue defined tumour necrosis factor (TNF) as a potential therapeutic target. Here we assessed the efficacy of injecting nodules of Dupuytren's disease with a TNF inhibitor. METHODS: Patients were randomised to receive adalimumab on one occasion in dose cohorts of 15 mg in 0.3 ml, 35 mg in 0.7 ml, or 40 mg in 0.4 ml, or an equivalent volume of placebo in a 3:1 ratio. Two weeks later the injected tissue was surgically excised and analysed. The primary outcome measure was levels of mRNA expression for α-smooth muscle actin (ACTA2). Secondary outcomes included levels of α-SMA and collagen proteins. The trial was registered with ClinicalTrial.gov (NCT03180957) and the EudraCT (2015-001780-40). FINDINGS: We recruited 28 patients, 8 assigned to the 15 mg, 12 to the 35 mg and 8 to the 40 mg adalimumab cohorts. There was no change in mRNA levels for ACTA2, COL1A1, COL3A1 and CDH11. Levels of α-SMA protein expression in patients treated with 40 mg adalimumab (1.09 ±â€¯0.09 ng per µg of total protein) were significantly lower (p = 0.006) compared to placebo treated patients (1.51 ±â€¯0.09 ng/µg). The levels of procollagen type I protein expression were also significantly lower (p < 0.019) in the sub group treated with 40 mg adalimumab (474 ±â€¯84 pg/µg total protein) compared with placebo (817 ±â€¯78 pg/µg). There were two serious adverse events, both considered unrelated to the study drug. INTERPRETATION: In this dose-ranging study, injection of 40 mg of adalimumab in 0.4 ml resulted in down regulation of the myofibroblast phenotype as evidenced by reduction in expression of α-SMA and type I procollagen proteins at 2 weeks. These data form the basis of an ongoing phase 2b clinical trial assessing the efficacy of intranodular injection of 40 mg adalimumab in 0.4 ml compared to an equivalent volume of placebo in patients with early stage Dupuytren's disease. FUNDING: Health Innovation Challenge Fund (Wellcome Trust and Department of Health) and 180 Therapeutics LP.


Subject(s)
Actins/metabolism , Adalimumab/administration & dosage , Anti-Inflammatory Agents/administration & dosage , Collagen Type I/metabolism , Dupuytren Contracture/drug therapy , Actins/genetics , Adalimumab/pharmacology , Anti-Inflammatory Agents/pharmacology , Collagen Type I/genetics , Double-Blind Method , Down-Regulation , Drug Administration Schedule , Dupuytren Contracture/genetics , Dupuytren Contracture/metabolism , Female , Gene Expression Regulation/drug effects , Humans , Injections , Male , Treatment Outcome
2.
Plast Reconstr Surg ; 131(3): 473-485, 2013 Mar.
Article in English | MEDLINE | ID: mdl-23446562

ABSTRACT

BACKGROUND: In autogenous muscle transplantation, unpredictable complications can cause prolonged ischemia, resulting in ischemia-reperfusion injury. The authors investigated the efficacy and mechanism of nicorandil, a nitrovasodilator and adenosine triphosphate-sensitive potassium channel opener, in inducing perioperative protection of muscle flaps from ischemia-reperfusion injury. METHODS: Pigs (18.2 ± 2.4 kg) were assigned to one control and eight treatment groups. Bilateral latissimus dorsi muscle flaps were raised after saline administration (control) and 0, 4, 8, 12, 24, 48, 72, and 96 hours after nicorandil administration. Subsequently, flaps were subjected to 4 hours of ischemia and 48 hours of reperfusion. Viability was assessed, and biochemical probes were used to study nicorandil-induced infarct protection. RESULTS: Protection by nicorandil was biphasic. Infarction reduced from 40.2 ± 1.9 percent (control) to 27.3 ± 1.7 percent and 24.0 ± 2.3 percent (p < 0.05) 0 and 4 hours after nicorandil administration, respectively (early phase protection). No difference was seen between control and treatment groups between 8 and 12 hours after nicorandil administration compared with the control. Infarct protection increased again (p < 0.05) at 24 (22.4 ± 2.0 percent), 48 (25.1 ± 2.1 percent), and 72 hours (28.5 ± 2.1 percent) but not at 96 hours (43.9 ± 4.6 percent) compared with control (late phase protection). The sarcolemmal and mitochondrial channels played a central role in the trigger and mediator mechanisms, respectively. Late protection was associated with lower myeloperoxidase activity and mitochondrial calcium overload and higher adenosine triphosphate content (p < 0.05). CONCLUSIONS: Nicorandil induced 48-hour uninterrupted muscle infarct protection, starting 24 hours after intravenous administration. This category of clinical drug is a potential prophylactic treatment against skeletal muscle ischemia-reperfusion injury in reconstructive surgery.


Subject(s)
Muscle, Skeletal/blood supply , Muscle, Skeletal/transplantation , Nicorandil/therapeutic use , Plastic Surgery Procedures , Postoperative Complications/prevention & control , Reperfusion Injury/prevention & control , Surgical Flaps/blood supply , Vasodilator Agents/therapeutic use , Animals , Swine
3.
Eur J Pharmacol ; 686(1-3): 90-6, 2012 Jul 05.
Article in English | MEDLINE | ID: mdl-22575519

ABSTRACT

In reconstructive surgery, skeletal muscle may endure protracted ischemia before reperfusion, which can lead to significant ischemia/reperfusion injury. Ischemic postconditioning induced by brief cycles of reperfusion/reocclusion at the end of ischemia has been shown to salvage skeletal muscle from ischemia/reperfusion injury in several animal models. However, ischemic postconditioning has not been confirmed in human skeletal muscle. Using an established in vitro human skeletal muscle hypoxic conditioning model, we tested our hypothesis that hypoxic postconditioning salvages ex vivo human skeletal muscle from hypoxia/reoxygenation injury and the mechanism involves inhibition of opening of the mitochondrial permeability transition pore (mPTP) and preservation of ATP synthesis. Muscle strips (~0.5×0.5×15mm) from human rectus abdominis muscle biopsies were cultured in Krebs-Henseleit-HEPES buffer, bubbled with 95%N(2)/5%CO(2) (hypoxia) or 95%O(2)/5%CO(2) (reoxygenation). Samples were subjected to 3h hypoxia/2h reoxygenation. Hypoxic postconditioning was induced by one or two cycles of 5min reoxygenation/5min hypoxia after 3h hypoxia. Muscle injury, viability and ATP synthesis after 2h of reoxygenation were assessed by measuring lactate dehydrogenase (LDH) release, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) reduction and ATP content, respectively. Hypoxic postconditioning or treatment with the mPTP-opening inhibitors Cyclosporine A (CsA, 5×10(-6)M) or N-Methyl-4-isoleucine Cyclosporine (NIM811, 5×10(-6)M) 10min before reoxygenation decreased LDH release, increased MTT reduction and increased muscle ATP content (n=7 patients; P<0.05). Conversely, treatment with the mPTP opener Atractyloside (5×10(-6)M) 10min before hypoxic postconditioning abolished its protective effect (n=7 patients; P<0.05). We conclude that hypoxic postconditioning effectively salvages human skeletal muscle from hypoxia/reoxygenation injury by inhibition of mPTP opening and preservation of ATP synthesis during reoxygenation.


Subject(s)
Hypoxia/physiopathology , Ischemic Postconditioning , Rectus Abdominis/physiopathology , Reperfusion Injury , Adenosine Triphosphate/metabolism , Aged , Cell Survival , Cyclosporine/pharmacology , Female , Humans , In Vitro Techniques , Middle Aged , Mitochondrial Membrane Transport Proteins/antagonists & inhibitors , Mitochondrial Permeability Transition Pore , Oxygen
4.
J Appl Physiol (1985) ; 106(1): 20-8, 2009 Jan.
Article in English | MEDLINE | ID: mdl-19023020

ABSTRACT

Administration of Na(+)/H(+) exchange isoform-1 (NHE-1) inhibitors before ischemia has been shown to attenuate myocardial infarction in several animal models of ischemia-reperfusion injury. However, controversy still exists as to the efficacy of NHE-1 inhibitors in protection of myocardial infarction when administered at the onset of reperfusion. Furthermore, the efficacy of NHE-1 inhibition in protection of skeletal muscle from infarction (necrosis) has not been studied. This information has potential clinical applications in prevention or salvage of skeletal muscle from ischemia-reperfusion injury in elective and trauma reconstructive surgery. The objective of this research project is to test our hypothesis that the NHE-1 inhibitor cariporide is effective in protection of skeletal muscle from infarction when administered at the onset of sustained ischemia or reperfusion and to study the mechanism of action of cariporide. In our studies, we observed that intravenous administration of cariporide 10 min before ischemia (1 or 3 mg/kg) or reperfusion (3 mg/kg) significantly reduced infarction in pig latissimus dorsi muscle flaps compared with the control, when these muscle flaps were subjected to 4 h of ischemia and 48 h of reperfusion (P < 0.05; n = 5 pigs/group). Both preischemic and postischemic cariporide treatment (3 mg/kg) induced a significant decrease in muscle myeloperoxidase activity and mitochondrial-free Ca(2+) content and a significant increase in muscle ATP content within 2 h of reperfusion (P < 0.05; n = 4 pigs/group). Preischemic and postischemic cariporide treatment (3 mg/kg) also significantly inhibited muscle NHE-1 protein expression within 2 h of reperfusion after 4 h of ischemia, compared with the control (P < 0.05; n = 3 pigs/group). These observations support our hypothesis that cariporide attenuates skeletal muscle infarction when administered at the onset of ischemia or reperfusion, and the mechanism involves attenuation of neutrophil accumulation and mitochondrial-free Ca(2+) overload and preservation of ATP synthesis in the early stage of reperfusion.


Subject(s)
Enzyme Inhibitors/pharmacology , Guanidines/pharmacology , Infarction/prevention & control , Muscle, Skeletal/blood supply , Muscle, Skeletal/drug effects , Reperfusion Injury/prevention & control , Sodium-Hydrogen Exchangers/antagonists & inhibitors , Sulfones/pharmacology , Adenosine Triphosphate/metabolism , Animals , Calcium/metabolism , Castration , Disease Models, Animal , Drug Administration Schedule , Enzyme Inhibitors/administration & dosage , Guanidines/administration & dosage , Infarction/enzymology , Infarction/pathology , Injections, Intravenous , Mitochondria, Muscle/drug effects , Mitochondria, Muscle/enzymology , Muscle, Skeletal/enzymology , Muscle, Skeletal/pathology , Muscle, Skeletal/surgery , Necrosis , Neutrophil Infiltration/drug effects , Neutrophils/drug effects , Neutrophils/enzymology , Peroxidase/metabolism , Reperfusion Injury/enzymology , Reperfusion Injury/pathology , Sodium-Hydrogen Exchangers/metabolism , Sulfones/administration & dosage , Surgical Flaps , Swine , Time Factors
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