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Mooranian A, Ionescu CM, Wagle SR, Kovacevic B, Walker D, Jones M, Chester J, Foster T, Johnston E, Mikov M, Atlas MD, Al-Salami H. Probucol Pharmacological and Bio-Nanotechnological Effects on Surgically Transplanted Graft Due to Powerful Anti-Inflammatory, Anti-Fibrotic and Potential Bile Acid Modulatory Actions. Pharmaceutics 2021; 13:pharmaceutics13081304. [PMID: 34452266 PMCID: PMC8398853 DOI: 10.3390/pharmaceutics13081304] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Revised: 08/03/2021] [Accepted: 08/05/2021] [Indexed: 12/22/2022] Open
Abstract
INTRODUCTION A major obstacle in islet transplantation and graft survival pre and post transplantation is islet apoptosis due to mainly inflammatory bio molecules released during islet harvesting and post graft transplantation and hence, subsequent graft fibrosis and failure. This study aimed to investigate if incorporation of the anti-inflammatory anti-hyperlipidaemic drug probucol (PB) would improve islet-graft survival and function, post transplantation in Type 1 diabetes (T1D). METHODS T1D was induced in mice, and biological profiles of the diabetic mice transplanted PB-microencapsulated islets harvested from healthy syngeneic mice were measured. RESULTS AND CONCLUSION Compared with sham (no PB), the treated group showed significant reduction in serum levels of interleukin-1β, interleukin-6, interleukin-12, interleukin-17, and tumour necrosis factor-α, accompanied by a 3-fold increase in survival duration, which suggests PB islet-protective effects, post transplantation.
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Affiliation(s)
- Armin Mooranian
- The Biotechnology and Drug Development Research Laboratory, Curtin Medical School & Curtin Health Innovation Research Institute, Curtin University, Bentley, Perth, WA 6102, Australia; (A.M.); (C.M.I.); (S.R.W.); (B.K.); (D.W.); (M.J.); (J.C.); (T.F.); (E.J.)
- Hearing Therapeutics, Ear Science Institute Australia, Queen Elizabeth II Medical Centre, Nedlands, Perth, WA 6009, Australia;
| | - Corina Mihaela Ionescu
- The Biotechnology and Drug Development Research Laboratory, Curtin Medical School & Curtin Health Innovation Research Institute, Curtin University, Bentley, Perth, WA 6102, Australia; (A.M.); (C.M.I.); (S.R.W.); (B.K.); (D.W.); (M.J.); (J.C.); (T.F.); (E.J.)
- Hearing Therapeutics, Ear Science Institute Australia, Queen Elizabeth II Medical Centre, Nedlands, Perth, WA 6009, Australia;
| | - Susbin Raj Wagle
- The Biotechnology and Drug Development Research Laboratory, Curtin Medical School & Curtin Health Innovation Research Institute, Curtin University, Bentley, Perth, WA 6102, Australia; (A.M.); (C.M.I.); (S.R.W.); (B.K.); (D.W.); (M.J.); (J.C.); (T.F.); (E.J.)
- Hearing Therapeutics, Ear Science Institute Australia, Queen Elizabeth II Medical Centre, Nedlands, Perth, WA 6009, Australia;
| | - Bozica Kovacevic
- The Biotechnology and Drug Development Research Laboratory, Curtin Medical School & Curtin Health Innovation Research Institute, Curtin University, Bentley, Perth, WA 6102, Australia; (A.M.); (C.M.I.); (S.R.W.); (B.K.); (D.W.); (M.J.); (J.C.); (T.F.); (E.J.)
- Hearing Therapeutics, Ear Science Institute Australia, Queen Elizabeth II Medical Centre, Nedlands, Perth, WA 6009, Australia;
| | - Daniel Walker
- The Biotechnology and Drug Development Research Laboratory, Curtin Medical School & Curtin Health Innovation Research Institute, Curtin University, Bentley, Perth, WA 6102, Australia; (A.M.); (C.M.I.); (S.R.W.); (B.K.); (D.W.); (M.J.); (J.C.); (T.F.); (E.J.)
- Hearing Therapeutics, Ear Science Institute Australia, Queen Elizabeth II Medical Centre, Nedlands, Perth, WA 6009, Australia;
| | - Melissa Jones
- The Biotechnology and Drug Development Research Laboratory, Curtin Medical School & Curtin Health Innovation Research Institute, Curtin University, Bentley, Perth, WA 6102, Australia; (A.M.); (C.M.I.); (S.R.W.); (B.K.); (D.W.); (M.J.); (J.C.); (T.F.); (E.J.)
- Hearing Therapeutics, Ear Science Institute Australia, Queen Elizabeth II Medical Centre, Nedlands, Perth, WA 6009, Australia;
| | - Jacqueline Chester
- The Biotechnology and Drug Development Research Laboratory, Curtin Medical School & Curtin Health Innovation Research Institute, Curtin University, Bentley, Perth, WA 6102, Australia; (A.M.); (C.M.I.); (S.R.W.); (B.K.); (D.W.); (M.J.); (J.C.); (T.F.); (E.J.)
- Hearing Therapeutics, Ear Science Institute Australia, Queen Elizabeth II Medical Centre, Nedlands, Perth, WA 6009, Australia;
| | - Thomas Foster
- The Biotechnology and Drug Development Research Laboratory, Curtin Medical School & Curtin Health Innovation Research Institute, Curtin University, Bentley, Perth, WA 6102, Australia; (A.M.); (C.M.I.); (S.R.W.); (B.K.); (D.W.); (M.J.); (J.C.); (T.F.); (E.J.)
- Hearing Therapeutics, Ear Science Institute Australia, Queen Elizabeth II Medical Centre, Nedlands, Perth, WA 6009, Australia;
| | - Edan Johnston
- The Biotechnology and Drug Development Research Laboratory, Curtin Medical School & Curtin Health Innovation Research Institute, Curtin University, Bentley, Perth, WA 6102, Australia; (A.M.); (C.M.I.); (S.R.W.); (B.K.); (D.W.); (M.J.); (J.C.); (T.F.); (E.J.)
- Hearing Therapeutics, Ear Science Institute Australia, Queen Elizabeth II Medical Centre, Nedlands, Perth, WA 6009, Australia;
| | - Momir Mikov
- Department of Pharmacology, Toxicology and Clinical Pharmacology, Faculty of Medicine, University of Novi Sad, Hajduk Veljkova 3, 21101 Novi Sad, Serbia;
| | - Marcus D. Atlas
- Hearing Therapeutics, Ear Science Institute Australia, Queen Elizabeth II Medical Centre, Nedlands, Perth, WA 6009, Australia;
| | - Hani Al-Salami
- The Biotechnology and Drug Development Research Laboratory, Curtin Medical School & Curtin Health Innovation Research Institute, Curtin University, Bentley, Perth, WA 6102, Australia; (A.M.); (C.M.I.); (S.R.W.); (B.K.); (D.W.); (M.J.); (J.C.); (T.F.); (E.J.)
- Hearing Therapeutics, Ear Science Institute Australia, Queen Elizabeth II Medical Centre, Nedlands, Perth, WA 6009, Australia;
- Correspondence: ; Tel.: +61-8-9266-9816; Fax: +61-8-9266-2769
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The effect of a tertiary bile acid, taurocholic acid, on the morphology and physical characteristics of microencapsulated probucol: potential applications in diabetes: a characterization study. Drug Deliv Transl Res 2016; 5:511-22. [PMID: 26242686 DOI: 10.1007/s13346-015-0248-9] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
In recent studies, we designed multi-compartmental microcapsules as a platform for the targeted oral delivery of lipophilic drugs in an animal model of type 2 diabetes (T2D). Probucol (PB) is a highly lipophilic, antihyperlipidemic drug with potential antidiabetic effects. PB has low bioavailability and high inter-individual variations in absorption, which limits its clinical applications. In a new study, the bile acid, taurocholic acid (TCA), exerted permeation enhancing effects in vivo. Accordingly, this study aimed to design and characterize TCA-based PB microcapsules and examine the effects of TCA on the microcapsules' morphology, stability, and release profiles. Microcapsules were prepared using the polymer sodium alginate (SA). Two types of microcapsules were produced, one without TCA (PB-SA, control) and one with TCA (PB-TCA-SA, test). Microcapsules were studied in terms of morphology, surface structure and composition, size, drug contents, cross-sectional imaging (using microtomography (Micro-CT) analysis), Zeta potential, thermal and chemical profiles, rheological parameters, swelling, mechanical strength, and release studies at various temperature and pH values. The production yield and the encapsulation efficiency were also studied together with in vitro efficacy testing of cell viability at various glucose concentrations and insulin and TNF-α production using clonal-mouse pancreatic β-cells. PB-TCA-SA microcapsules showed uniform structure and even distribution of TCA within the microcapsules. Drug contents, Zeta potential, size, rheological parameters, production yield, and the microencapsulation efficiency remained similar after TCA addition. In vitro testing showed PB-TCA-SA microcapsules improved β-cell survival under hyperglycemic states and reduced the pro-inflammatory cytokine TNF-α while increasing insulin secretions compared with PB-SA microcapsules. PB-TCA-SA microcapsules also showed good stability, better mechanical (p < 0.01) and swelling (p < 0.01) characteristics, and optimized controlled release at pH 7.8 (p < 0.01) compared with control, suggesting desirable targeted release properties and potential applications in the oral delivery of PB in T2D.
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Mooranian A, Negrulj R, Mikov M, Golocorbin-Kon S, Arfuso F, Al-Salami H. Novel chenodeoxycholic acid-sodium alginate matrix in the microencapsulation of the potential antidiabetic drug, probucol. An in vitro study. J Microencapsul 2015; 32:589-97. [PMID: 26190214 DOI: 10.3109/02652048.2015.1065922] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
CONTEXT We previously designed, developed and characterized a novel microencapsulated formulation as a platform for the targeted delivery of Probucol (PB) in an animal model of Type 2 Diabetes. OBJECTIVE The objective of this study is to optimize this platform by incorporating Chenodeoxycholic acid (CDCA), a bile acid with good permeation-enhancing properties, and examine its effect in vitro. Using sodium alginate (SA), we prepared PB-SA (control) and PB-CDCA-SA (test) microcapsules. RESULTS AND DISCUSSION CDCA resulted in better structural and surface characteristics, uniform morphology, and stable chemical and thermal profiles, while size and rheological parameters remained unchanged. PB-CDCA-SA microcapsules showed good excipients' compatibilities, as evidenced by differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy, scanning electron microscopy and energy dispersive X-ray spectroscopy studies. CDCA reduced microcapsule swelling at pH 7.8 at both 37 °C and 25 °C and improved PB-release. CONCLUSION CDCA improved the characteristics and release properties of PB-microcapsules and may have potential in the targeted oral delivery of PB.
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Affiliation(s)
- Armin Mooranian
- a Biotechnology and Drug Development Research Laboratory, School of Pharmacy, Curtin Health Innovation Research Institute, Curtin University , Perth, Western Australia , Australia
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Mooranian A, Negrulj R, Al-Sallami HS, Fang Z, Mikov M, Golocorbin-Kon S, Fakhoury M, Watts GF, Matthews V, Arfuso F, Lambros A, Al-Salami H. Probucol release from novel multicompartmental microcapsules for the oral targeted delivery in type 2 diabetes. AAPS PharmSciTech 2015; 16:45-52. [PMID: 25168450 DOI: 10.1208/s12249-014-0205-9] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2014] [Accepted: 08/14/2014] [Indexed: 11/30/2022] Open
Abstract
In previous studies, we developed and characterised multicompartmental microcapsules as a platform for the targeted oral delivery of lipophilic drugs in type 2 diabetes (T2D). We also designed a new microencapsulated formulation of probucol-sodium alginate (PB-SA), with good structural properties and excipient compatibility. The aim of this study was to examine the stability and pH-dependent targeted release of the microcapsules at various pH values and different temperatures. Microencapsulation was carried out using a Büchi-based microencapsulating system developed in our laboratory. Using SA polymer, two formulations were prepared: empty SA microcapsules (SA, control) and loaded SA microcapsules (PB-SA, test), at a constant ratio (1:30), respectively. Microcapsules were examined for drug content, zeta potential, size, morphology and swelling characteristics and PB release characteristics at pH 1.5, 3, 6 and 7.8. The production yield and microencapsulation efficiency were also determined. PB-SA microcapsules had 2.6 ± 0.25% PB content, and zeta potential of -66 ± 1.6%, suggesting good stability. They showed spherical and uniform morphology and significantly higher swelling at pH 7.8 at both 25 and 37°C (p < 0.05). The microcapsules showed multiphasic release properties at pH 7.8. The production yield and microencapsulation efficiency were high (85 ± 5 and 92 ± 2%, respectively). The PB-SA microcapsules exhibited distal gastrointestinal tract targeted delivery with a multiphasic release pattern and with good stability and uniformity. However, the release of PB from the microcapsules was not controlled, suggesting uneven distribution of the drug within the microcapsules.
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Mooranian A, Negrulj R, Chen-Tan N, Al-Sallami HS, Fang Z, Mukkur TK, Mikov M, Golocorbin-Kon S, Fakhoury M, Watts GF, Matthews V, Arfuso F, Al-Salami H. Microencapsulation as a novel delivery method for the potential antidiabetic drug, Probucol. DRUG DESIGN DEVELOPMENT AND THERAPY 2014; 8:1221-30. [PMID: 25246766 PMCID: PMC4166910 DOI: 10.2147/dddt.s67349] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Introduction In previous studies, we successfully designed complex multicompartmental microcapsules as a platform for the oral targeted delivery of lipophilic drugs in type 2 diabetes (T2D). Probucol (PB) is an antihyperlipidemic and antioxidant drug with the potential to show benefits in T2D. We aimed to create a novel microencapsulated formulation of PB and to examine the shape, size, and chemical, thermal, and rheological properties of these microcapsules in vitro. Method Microencapsulation was carried out using the Büchi-based microencapsulating system developed in our laboratory. Using the polymer, sodium alginate (SA), empty (control, SA) and loaded (test, PB-SA) microcapsules were prepared at a constant ratio (1:30). Complete characterizations of microcapsules, in terms of morphology, thermal profiles, dispersity, and spectral studies, were carried out in triplicate. Results PB-SA microcapsules displayed uniform and homogeneous characteristics with an average diameter of 1 mm. The microcapsules exhibited pseudoplastic-thixotropic characteristics and showed no chemical interactions between the ingredients. These data were further supported by differential scanning calorimetric analysis and Fourier transform infrared spectral studies, suggesting microcapsule stability. Conclusion The new PB-SA microcapsules have good structural properties and may be suitable for the oral delivery of PB in T2D. Further studies are required to examine the clinical efficacy and safety of PB in T2D.
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Affiliation(s)
- Armin Mooranian
- Biotechnology and Drug Development Research Laboratory School of Pharmacy, Curtin Health Innovation Research Institute, Biosciences Research Precinct, Curtin University, Perth, Western Australia, Australia
| | - Rebecca Negrulj
- Biotechnology and Drug Development Research Laboratory School of Pharmacy, Curtin Health Innovation Research Institute, Biosciences Research Precinct, Curtin University, Perth, Western Australia, Australia
| | - Nigel Chen-Tan
- Faculty of Science and Engineering, Curtin University, Perth, Western Australia, Australia
| | | | - Zhongxiang Fang
- School of Public Health, Curtin University, Perth, Western Australia, Australia
| | - T K Mukkur
- Curtin Health Innovation Research Institute, Biosciences Research Precinct, School of Biomedical Science, Curtin University, Perth, Western Australia, Australia
| | - Momir Mikov
- Department of Pharmacology, Toxicology and Clinical Pharmacology, Faculty of Medicine, University of Novi Sad, Serbia ; Department of Pharmacy, Faculty of Medicine, University of Novi Sad, Serbia
| | - Svetlana Golocorbin-Kon
- Department of Pharmacology, Toxicology and Clinical Pharmacology, Faculty of Medicine, University of Novi Sad, Serbia ; Department of Pharmacy, Faculty of Medicine, University of Novi Sad, Serbia
| | - Marc Fakhoury
- Faculty of Medicine, University of Montreal, Montreal, Quebec, Canada
| | - Gerald F Watts
- School of Medicine and Pharmacology, Royal Perth Hospital, University of Western Australia
| | - Vance Matthews
- Laboratory for Metabolic Dysfunction, UWA Centre for Medical Research, Harry Perkins Institute of Medical Research, Perth, Western Australia, Australia
| | - Frank Arfuso
- Curtin Health Innovation Research Institute, Biosciences Research Precinct, School of Biomedical Science, Curtin University, Perth, Western Australia, Australia
| | - Hani Al-Salami
- Biotechnology and Drug Development Research Laboratory School of Pharmacy, Curtin Health Innovation Research Institute, Biosciences Research Precinct, Curtin University, Perth, Western Australia, Australia
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Tanous D, Hime N, Stocker R. Anti-atherosclerotic and anti-diabetic properties of probucol and related compounds. Redox Rep 2013; 13:48-59. [DOI: 10.1179/135100008x259196] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
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Takatori A, Ohta E, Inenaga T, Horiuchi K, Ishii Y, Itagaki SI, Kyuwa S, Yoshikawa Y. Protective Effects of Probucol Treatment on Pancreatic .BETA.-cell Function of SZ-induced Diabetic APA Hamsters. Exp Anim 2003; 52:317-27. [PMID: 14562608 DOI: 10.1538/expanim.52.317] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
To clarify whether oxidative stress is involved in the pathogenesis of islet lesions of diabetic animals, the effects of probucol (PB), an antioxidant and anti-hyperlipidemia agent, on the islets in streptozotocin (SZ)-induced diabetic APA hamsters in the acute and chronic phases of diabetes were examined. The control (CB group) and diabetic (SZ group) hamsters were treated with PB (1% in the diet) for 4 weeks from several days after SZ injection as the acute diabetic group, or 8 weeks from 6 weeks after SZ injection as the chronic diabetic group. Glucose tolerance test revealed that PB treatment decreased the high serum glucose level after glucose injection in the diabetic APA hamsters in the acute diabetic phase. Immunohistochemistry revealed that PB treatment significantly increased the percentage of the insulin positive area in the diabetic hamsters pancreata in both the acute and chronic phases. In addition, 4-hydroxy-2-nonenal (4HNE; an oxidative stress marker) positive cells were slightly reduced by PB treatment in the acute diabetic phase. Double-immunostaining for insulin and PCNA (proliferating cell nuclear antigen) revealed that elevation of the percentage of insulin and PCNA double-positive cells against insulin-positive cells was seen in the islets of PB-treated diabetic hamsters, but the difference was not significant compared with untreated diabetic hamsters (p = 0.07). In semi-quantitative RT-PCR, the expression of two genes, Reg (Regenerating gene) and INGAP (islet neogenesis associated protein), in the diabetic APA hamsters was significantly increased compared to the control groups in both diabetic phases. PB treatment significantly reduced Reg expression in the chronic diabetic phase. These data suggest that PB treatment in SZ-injected diabetic hamsters partially restored beta-cell function through acting as an antioxidant and induced higher expression of Reg and INGAP genes in the pancreas of hamsters.
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Affiliation(s)
- Atsushi Takatori
- Department of Biomedical Science, Graduate School of Agricultural and Life Sciences, University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
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Ogawa J, Takahashi S, Fujiwara T, Fukushige J, Hosokawa T, Izumi T, Kurakata S, Horikoshi H. Troglitazone can prevent development of type 1 diabetes induced by multiple low-dose streptozotocin in mice. Life Sci 1999; 65:1287-96. [PMID: 10503944 DOI: 10.1016/s0024-3205(99)00364-1] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Recent investigations suggest that cytotoxic cytokines such as tumor necrosis factor (TNF)alpha and interleukin (IL)-1beta or free radicals play an essential role in destruction of pancreatic beta cells in Type 1 diabetes and that, therefore, anti-oxidant or anti-TNF alpha and IL-1beta therapy could prevent the development of Type I diabetes. Troglitazone belongs to a novel class of antidiabetic agent possessing the ability to enhance insulin action provably through activating PPAR gamma and to scavenge free radicals. In the present study, we examined whether troglitazone can prevent the development of Type 1 diabetes in multiple, low-dose streptozotocin (MLDSTZ)-injected mice. In addition, effects of troglitazone on cytokine-induced pancreatic beta cell damage were examined in vitro. Type 1 diabetes was induced by MLDSTZ injection to DBA/2 mice (40 mg/kg/day for 5 days). Troglitazone was administered as a 0.2% food admixture (240 mg/kg/day) for 4 weeks from the start of or immediately after STZ injection. MLDSTZ injection elevated plasma glucose to 615 +/- 8 mg/dl 4 weeks after final STZ injection and was accompanied by infiltration of leukocytes to pancreatic islets (insulitis). Troglitazone treatment with MLDSTZ injection prevented hyperglycemia (230 +/- 30 mg/dl) and, suppressed insulitis and TNF alpha production from intraperitoneal exudate cells. TNF alpha (10 pg/ml) and IL-1beta (1 pg/ml) addition to hamster insulinoma cell line HIT-T15 for 7 days in vitro decreased insulin secretion and cell viability. Simultaneous troglitazone addition (0.03 to approximately 3 microM) significantly improved cytokine-induced decrease in insulin secretion and in cell viability. These findings suggest that troglitazone prevents the development of Type 1 diabetes in the MLDSTZ model by suppressing insulitis associated with decreasing TNF alpha production from intraperitoneal exudate cells and the subsequent TNF alpha and IL-1beta-induced beta cell damage.
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Affiliation(s)
- J Ogawa
- Pharmacology & Molecular Biology, Research Laboratories, Sankyo Co, Ltd., Tokyo, Japan
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Abstract
Islet cells cocultured with activated macrophages are lysed within 15 h in vitro. We showed previously that nitric oxide generated by macrophages is a major mediator of islet cell death. We have now probed several pathways to interfere with the chain of events leading to islet cell death. Scavenging of extracellular oxygen radicals by superoxide dismutase and catalase did not improve islet cell survival. Scavenging of extra- and intracellular oxygen radicals by two potent substances, citiolone and dimethyl-thiourea, also did not reduce islet cell lysis, while a lipid-soluble scavenger, probucol, provided partial protection. These findings argue against a synergistic action of nitric oxide and oxygen radicals in islet cell toxicity. The inhibition of poly(ADP-ribose)polymerase by 3-aminobenzamide significantly improved islet cell survival. Selective inhibitors of cyclooxygenase, such as indomethacin or acetylsalicylic acid, did not improve islet cell survival. Full protection was seen in the presence of NDGA, an inhibitor of lipoxygenase, and partial suppression was caused by BW755c, an inhibitor of both lipoxygenase and cyclooxygenase. We conclude that inflammatory islet cell death caused by activated macrophages involves the activation of arachidonic acid metabolism and of poly(ADP-ribose)polymerase, but that scavenging of oxygen free radicals provides little protection from lysis.
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Affiliation(s)
- V Burkart
- Diabetes Research Institute, Heinrich-Heine University, Düsseldorf, Germany
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