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Niloy KK, Lowe TL. Injectable systems for long-lasting insulin therapy. Adv Drug Deliv Rev 2023; 203:115121. [PMID: 37898336 DOI: 10.1016/j.addr.2023.115121] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2023] [Revised: 10/20/2023] [Accepted: 10/25/2023] [Indexed: 10/30/2023]
Abstract
Insulin therapy is the mainstay to treat diabetes characterizedd by hyperglycemia. However, its short half-life of only 4-6 min limits its effectiveness in treating chronic diabetes. Advances in recombinant DNA technology and protein engineering have led to several insulin analogue products that have up to 42 h of glycemic control. However, these insulin analogues still require once- or twice-daily injections for optimal glycemic control and have poor patient compliance and adherence issues. To achieve insulin release for more than one day, different injectable delivery systems including microspheres, in situ forming depots, nanoparticles and composite systems have been developed. Several of these delivery systems have advanced to clinical trials for once-weekly insulin injection. This review comprehensively summarizes the developments of injectable insulin analogs and delivery systems covering the whole field of injectable long-lasting insulin technologies from prototype design, preclinical studies, clinical trials to marketed products for the treatment of diabetes.
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Affiliation(s)
- Kumar Kulldeep Niloy
- Department of Pharmaceutical Sciences, University of Tennessee Health Science Center, Memphis, TN 38163, USA; Department of Pharmaceutical Sciences, St. Jude Children's Research Hospital, Memphis, TN 38105, USA.
| | - Tao L Lowe
- Department of Pharmaceutical Sciences, University of Tennessee Health Science Center, Memphis, TN 38163, USA; Department of Oral and Maxillofacial Surgery, School of Dentistry, University of Maryland, Baltimore, MD 21201, USA; Fischell Department of Bioengineering, A. James Clark School of Engineering, University of Maryland, College Park, MD 20742, USA.
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2
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Kumar D, Gautam A, Rohatgi S, Kundu PP. Synthesis of vildagliptin loaded acrylamide-g-psyllium/alginate-based core-shell nanoparticles for diabetes treatment. Int J Biol Macromol 2022; 218:82-93. [PMID: 35841963 DOI: 10.1016/j.ijbiomac.2022.07.066] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2022] [Revised: 07/08/2022] [Accepted: 07/08/2022] [Indexed: 01/13/2023]
Abstract
Diabetes mellitus has become a major public health concern all over the world. Vildagliptin is one of the antidiabeticdrug that can overcome the existing problem of this prevalent disease. Present study aims to synthesize and investigate the role of vildagliptin-loaded core-shell nanoparticle of grafted psyllium and alginate (VG@P/A-NPs) in anti-diabetes application. FTIR, SEM, XRD, 13CNMR and zeta analyzer were used for characterization of the core-shell nanoparticles (VG@P/A-NPs). The synthesized acrylamide-grafted-psyllium was also optimized through varying grafting parameters such as acrylamide and ceric ammonium nitrate (CAN) concentration, time and temperature to obtain the maximum yield of acrylamide-grafted-psyllium. Rheological analysis of pure psyllium, grafted psyllium and alginate were also performed. For biological studies, the first cytotoxicity of grafted psyllium and VG@P/A-NPs were examined on human lung adenocarcinoma cell line A549 in which it was observed that VG@P/A-NPs did not exhibited any toxicity. The antidiabetic potential of VG@P/A-NPs was investigated by glucose uptake assay, using TNF-α induced insulin resistance skeletal cell model using mouse muscle L6 cell line. The insulin signaling impaired cell line displayed a highly significant (p < 0.0001) dose-dependent increase in glucose uptake after treatment with increasing doses of VG@P/A-NPs.The drug release behavior of VG@P/A-NPs was examined at various pH and the highest drug release (98 %) was obtained at pH (7.4). The drug release kinetic data was following the Higuchi (R2 = 0.9848) kinetic model, suggesting the release of drug from vildagliptin-loaded grafted psyllium-alginate core-shell nanoparticles (VG@P/A-NPs) as a square root of time-dependent process and diffusion controlled. This study provides an economical and environment-friendly approach towards the synthesis of VG@P/A-NPs with antidiabetes applications.
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Affiliation(s)
- Deepak Kumar
- Department of Chemical Engineering, Indian Institute of Technology Roorkee, India
| | - Arti Gautam
- Department of Biochemistry, Institute of Science, Banaras Hindu University, Varanasi, India
| | - Soma Rohatgi
- Department of Biosciences and Bioengineering, Indian Institute of Technology Roorkee, India
| | - Patit P Kundu
- Department of Chemical Engineering, Indian Institute of Technology Roorkee, India.
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Elassy N, El-Dafrawy S, Abd El-Azim AO, El-Khawaga OAY, Negm A. Zinc oxide nanoparticles augment CD4, CD8, and GLUT-4 expression and restrict inflammation response in streptozotocin-induced diabetic rats. IET Nanobiotechnol 2021; 14:680-687. [PMID: 33108324 DOI: 10.1049/iet-nbt.2020.0079] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
This study evaluated the biochemical, molecular, and histopathological mechanisms involved in the hypoglycaemic effect of zinc oxide nanoparticles (ZnONPs) in experimental diabetic rats. ZnONPs were prepared by the sol-gel method and characterised by scanning and transmission electron microscopy (SEM and TEM). To explore the possible hypoglycaemic and antioxidant effect of ZnONPs, rats were grouped as follows: control group, ZnONPs treated group, diabetic group, and diabetic + ZnONPs group. Upon treatment with ZnONPs, a significant alteration in the activities of superoxide dismutase, glutathione peroxidase, and the levels of insulin, haemoglobin A1c, and the expression of cluster of differentiation 4+ (CD4+), CD8+ T cells, glucose transporter type-4 (GLUT-4), tumour necrosis factor, and interleukin-6 when compared to diabetic and their control rats. ZnONPs administration to the diabetic group showed eminent blood glucose control and restoration of the biochemical profile. This raises their active role in controlling pancreas functions to improve glycaemic status as well as the inflammatory responses. Histopathological investigations showed the non-toxic and therapeutic effect of ZnONPs on the pancreas. TEM of pancreatic tissues displayed restoration of islets of Langerhans and increased insulin-secreting granules. This shows the therapeutic application of ZnONPs as a safe anti-diabetic agent and to have a potential for the control of diabetes.
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Affiliation(s)
- Norhan Elassy
- Chemistry Department, Faculty of Science, Mansoura University, 35516 Mansoura, Egypt
| | - Shady El-Dafrawy
- Chemistry Department, Faculty of Science, Mansoura University, 35516 Mansoura, Egypt
| | - Amira O Abd El-Azim
- Zoology Department, Faculty of Science, Mansoura University, 35516 Mansoura, Egypt
| | - Om Ali Y El-Khawaga
- Chemistry Department, Faculty of Science, Mansoura University, 35516 Mansoura, Egypt
| | - Amr Negm
- Department of Chemistry, College of Science, King Faisal University, Al-Ahsa, 31982 Saudi Arabia.
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Doufène K, Basile I, Lebrun A, Pirot N, Escande A, Chopineau J, Devoisselle JM, Bettache N, Aubert-Pouëssel A. Vegetable oil-based hybrid microparticles as a green and biocompatible system for subcutaneous drug delivery. Int J Pharm 2021; 592:120070. [PMID: 33188895 DOI: 10.1016/j.ijpharm.2020.120070] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Revised: 11/03/2020] [Accepted: 11/06/2020] [Indexed: 12/17/2022]
Abstract
The aim of this study was to evidence the ability of vegetable oil-based hybrid microparticles (HMP) to be an efficient and safe drug delivery system after subcutaneous administration. The HMP resulted from combination of a thermostabilized emulsification process and a sol-gel chemistry. First of all, castor oil was successfully silylated by means of (3-Isocyanatopropyl)trimethoxysilane in solvent-free and catalyst-free conditions. Estradiol, as a model drug, was dissolved in silylated castor oil (ICOm) prior to emulsification, and then an optimal sol-gel crosslinking was achieved inside the ICOm microdroplets. The resulting estradiol-loaded microparticles were around 80 µm in size and allowed to entrap 4 wt% estradiol. Their release kinetics in a PBS/octanol biphasic system exhibited a one-week release profile, and the released estradiol was fully active on HeLa ERE-luciferase ERα cells. The hybrid microparticles were cytocompatible during preliminary tests on NIH 3T3 fibroblasts (ISO 10993-5 standard) and they were fully biocompatible after subcutaneous injection on mice (ISO 10993-6 standard) underlining their high potential as a safe and long-acting subcutaneous drug delivery system.
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Affiliation(s)
- Koceïla Doufène
- Institut Charles Gerhardt Montpellier (ICGM), Univ. Montpellier, CNRS, ENSCM, Montpellier, France
| | | | - Aurélien Lebrun
- Laboratoire des Mesures Physiques (LMP), Univ. Montpellier, CNRS, Montpellier, France
| | - Nelly Pirot
- Institut de Recherche en Cancérologie de Montpellier (IRCM), Univ. Montpellier, ICM, INSERM, Montpellier, France; BioCampus Montpellier (BCM), Univ. Montpellier, CNRS, INSERM, Montpellier, France
| | - Aurélie Escande
- Hydrosciences Montpellier (HSM), Univ. Montpellier, CNRS, IRD, Montpellier, France
| | - Joël Chopineau
- Institut Charles Gerhardt Montpellier (ICGM), Univ. Montpellier, CNRS, ENSCM, Montpellier, France
| | - Jean-Marie Devoisselle
- Institut Charles Gerhardt Montpellier (ICGM), Univ. Montpellier, CNRS, ENSCM, Montpellier, France
| | - Nadir Bettache
- Institut des Biomolécules Max Mousseron (IBMM), Univ. Montpellier, CNRS, ENSCM, Montpellier, France
| | - Anne Aubert-Pouëssel
- Institut Charles Gerhardt Montpellier (ICGM), Univ. Montpellier, CNRS, ENSCM, Montpellier, France.
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Salim S, Kamalasanan K. Controlled drug delivery for alopecia: A review. J Control Release 2020; 325:84-99. [DOI: 10.1016/j.jconrel.2020.06.019] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 06/16/2020] [Accepted: 06/17/2020] [Indexed: 01/21/2023]
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Bottinelli C, Cartiser N, Bévalot F, Fanton L, Guitton J. Is insulin intoxication still the perfect crime? Analysis and interpretation of postmortem insulin: review and perspectives in forensic toxicology. Crit Rev Toxicol 2020; 50:324-347. [PMID: 32458714 DOI: 10.1080/10408444.2020.1762540] [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] [Indexed: 12/30/2022]
Abstract
Insulin is an anabolic hormone essential to glucose homeostasis. Insulin therapy, comprising human insulin (HI) or biosynthetic analogs, is critical for the management of type-1 diabetes and many of type-2 diabetes. However, medication error including non-adapted dose and confusion of insulin type, and misuse, such as massive self-administration or with criminal intent, can have lethal consequences. The aim of this paper is to review the state of knowledge of insulin analysis in biological samples and of the interpretation of insulin concentrations in the situation of insulin-related death investigations. Analytic aspects are considered, as quantification can be strongly impacted by methodology. Immunoanalysis, the historical technique, has a prominent role due to its sensitivity and ease of implementation. Recently, liquid chromatography coupled to mass spectrometry has provided indispensable selectivity in forensic contexts, distinguishing HI, analogs, and degradation products. We review the numerous antemortem (dose, associated pathology, injection-to-death interval, etc.) and postmortem parameters (in corpore degradation, in vitro degradation related to hemolysis, etc.) involved in the interpretation of insulin concentration. The interest and limitations of various alternative matrices providing a valuable complement to blood analysis are discussed. Vitreous humor is one of the most interesting, but the low diffusion of insulin in this matrix entails very low concentrations. Injection site analysis is relevant for identifying which type of insulin was administered. Muscle and renal cortex are matrices of particular interest, although additional studies are required. A table containing most case reports of fatal insulin poisoning published, with analytical data, completes this review. A logic diagram is proposed to highlight analytical issues and the main parameters to be considered for the interpretation of blood concentrations. Finally, it remains a challenge to provide reliable biological data and solid interpretation in the context of death related to insulin overdose. However, the progress of analytical tools is making the "perfect crime" ever more difficult to commit.
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Affiliation(s)
| | - Nathalie Cartiser
- Département de médecine légale, Hôpital Edouard-Herriot, Hospices Civils de Lyon, Lyon, France
| | | | - Laurent Fanton
- Département de médecine légale, Hôpital Edouard-Herriot, Hospices Civils de Lyon, Lyon, France.,Faculté de médecine Lyon Est, Institut de Médecine Légale, Université de Lyon, Université Claude Bernard Lyon 1, Lyon, France
| | - Jérôme Guitton
- Laboratoire de Toxicologie, ISPB-Faculté de Pharmacie, Université de Lyon, Université Claude Bernard Lyon 1, Lyon, France.,Hospices Civils de Lyon, Laboratoire de Pharmacologie-Toxicologie, Centre Hospitalier Lyon-Sud, Pierre Bénite Cedex, France
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Hoshi A, Nagai N, Daigaku R, Motoyama R, Saijo S, Kaji H, Abe T. Effect of sustained insulin-releasing device made of poly(ethylene glycol) dimethacrylates on retinal function in streptozotocin-induced diabetic rats. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2020; 31:52. [PMID: 32462459 DOI: 10.1007/s10856-020-06392-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Accepted: 05/15/2020] [Indexed: 06/11/2023]
Abstract
In this study, we developed a subcutaneous insulin-releasing device consisting of a disk-shaped capsule and drug formulation comprised of poly(ethylene glycol) dimethacrylates, then evaluated its efficacy on retinal function in streptozotocin (STZ)-induced diabetic rats. In vitro release studies showed that recombinant human insulin was released with a constant rate for more than 30 days. The device was able to maintain a basal level of blood glucose in diabetic rats for a prolonged period of more than 30 days, simultaneously preventing a decrease in body weight. For assessing the pharmacological effect of the device on retinal function in diabetic rats, electroretinograms were conducted for 12 weeks. The reduction in amplitude and delay in implicit time were attenuated by the device during the initial 4 weeks of application. The increase in gene expression of protein kinase C (PKC)-γ and caspase-3 in the diabetic retina was also attenuated by the device. Immunohistochemistry showed that the increase in glial fibrillary acidic protein expression in the diabetic retina was attenuated by the device. Histological evaluation of subcutaneous tissue around the device showed the biocompatibility of the device. In conclusion, the insulin-releasing device attenuated the reduction of retinal function in STZ-induced diabetic conditions for 4 weeks and the efficacy of the device might be partially related to PKC signaling in the retina. The long-term ability to control the blood glucose level might help to reduce the daily frequency of insulin injections.
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Affiliation(s)
- Ayako Hoshi
- Division of Clinical Cell Therapy, United Centers for Advanced Research and Translational Medicine (ART), Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai, 980-8575, Japan
| | - Nobuhiro Nagai
- Division of Clinical Cell Therapy, United Centers for Advanced Research and Translational Medicine (ART), Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai, 980-8575, Japan
| | - Reiko Daigaku
- Division of Clinical Cell Therapy, United Centers for Advanced Research and Translational Medicine (ART), Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai, 980-8575, Japan
| | - Remi Motoyama
- Division of Clinical Cell Therapy, United Centers for Advanced Research and Translational Medicine (ART), Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai, 980-8575, Japan
| | - Saaya Saijo
- Division of Clinical Cell Therapy, United Centers for Advanced Research and Translational Medicine (ART), Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai, 980-8575, Japan
| | - Hirokazu Kaji
- Department of Finemechanics, Graduate School of Engineering, Tohoku University, 6-6-01 Aramaki, Aoba-ku, Sendai, 980-8579, Japan
| | - Toshiaki Abe
- Division of Clinical Cell Therapy, United Centers for Advanced Research and Translational Medicine (ART), Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai, 980-8575, Japan.
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Kim NA, Thapa R, Jeong SH, Bae HD, Maeng J, Lee K, Park K. Enhanced intranasal insulin delivery by formulations and tumor protein-derived protein transduction domain as an absorption enhancer. J Control Release 2018; 294:226-236. [PMID: 30557648 DOI: 10.1016/j.jconrel.2018.12.023] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Revised: 11/26/2018] [Accepted: 12/13/2018] [Indexed: 02/06/2023]
Abstract
One of the key factors for successful development of an intranasal insulin formulation is an absorption enhancer that would deliver insulin efficiently across nasal membranes without causing damage to mucosa or inducing protein aggregation under physiological conditions. In the present study, a protein transduction domain (PTD1) and its L-form with the double substitution A6L and I8A (PTD4), derived from human translationally controlled tumor protein, were used as absorption enhancers. PTD4 exhibited higher compatibility with insulin in terms of biophysical properties analyzed using μDSC, DLS, and CD. In addition, thermodynamic properties indicated stable complex formation but higher propensity of protein aggregation. Arginine hydrochloride (ArgHCl) was used to suppress protein aggregation and carbohydrates (i.e., mannitol, sucrose, and glycerin) were used as osmolytes in the formulation. The relative bioavailability of insulin co-administered intranasally using PTD4, 16 mg/mL glycerin and 100 mM ArgHCl was 58% and that using PTD4, 1 w/v% sucrose, and 25 mM ArgHCl was 53% of the bioavailability obtained via the subcutaneous route. These values represented a remarkable increase in bioavailability of intranasal insulin, causing a significant decrease in blood glucose levels within one hour. The pharmacokinetic properties of intranasal absorption were dependent on the concentration of carbohydrates used. These results suggest that the newly designed formulations with PTD represent a useful platform for intranasal delivery of insulin and other biomolecules.
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Affiliation(s)
- Nam Ah Kim
- College of Pharmacy, Dongguk University-Seoul, Goyang, Gyeonggi 10326, Republic of Korea
| | - Ritu Thapa
- College of Pharmacy, Dongguk University-Seoul, Goyang, Gyeonggi 10326, Republic of Korea
| | - Seong Hoon Jeong
- College of Pharmacy, Dongguk University-Seoul, Goyang, Gyeonggi 10326, Republic of Korea.
| | - Hae-Duck Bae
- College of Pharmacy, Ewha Womans University, Seoul 03760, Republic of Korea
| | - Jeehye Maeng
- College of Pharmacy, Ewha Womans University, Seoul 03760, Republic of Korea
| | - Kyunglim Lee
- College of Pharmacy, Ewha Womans University, Seoul 03760, Republic of Korea
| | - Kinam Park
- Department of Pharmaceutics and Biomedical Engineering, Purdue University, West Lafayette, IN 47907, USA
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Zielińska J, Stadnik J, Bierczyńska-Krzysik A, Stadnik D. Identification of N-Terminally Truncated Derivatives of Insulin Analogs Formed in Pharmaceutical Formulations. Pharm Res 2018; 35:143. [PMID: 29770892 PMCID: PMC5956049 DOI: 10.1007/s11095-018-2426-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Accepted: 05/06/2018] [Indexed: 11/18/2022]
Abstract
PURPOSE Isolation and identification of unknown impurities of recombinant insulin lispro (produced at IBA) formed during accelerated stability testing of pharmaceutical solutions. For comparative purposes also commercially available formulations of recombinant human insulin (Humulin S®; Lilly), recombinant insulin lispro (Humalog®; Lilly), recombinant insulin aspart (NovoRapid® Penfill®; Novo Nordisk), recombinant insulin detemir (Levemir®; Novo Nordisk) and recombinant insulin glargine (Lantus®; Sanofi-Aventis) were analyzed. METHODS The impurities of insulin analogs were isolated by RP-HPLC and identified with peptide mass fingerprinting using MALDI-TOF/TOF mass spectrometry. RESULTS The identified derivatives were N-terminally truncated insulin analog impurities of decreased molecular mass of 119, 147 and 377 Da related to the original protein. The modifications resulting in a mass decrease were detected at the N-terminus of B chains of insulin lispro, insulin aspart, human insulin, insulin glargine, insulin detemir in all tested formulations. To our knowledge it is the first time that these impurities are reported. CONCLUSIONS The following derivatives formed by truncation of the B chain in insulin analogs were identified in pharmaceutical formulations: desPheB1-N-formyl-ValB2 derivative, desPheB1 derivative, pyroGluB4 derivative.
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Affiliation(s)
- Joanna Zielińska
- Institute of Biotechnology and Antibiotics (IBA), Starościńska 5, 02-516, Warsaw, Poland
| | - Jacek Stadnik
- Institute of Biotechnology and Antibiotics (IBA), Starościńska 5, 02-516, Warsaw, Poland
| | | | - Dorota Stadnik
- Institute of Biotechnology and Antibiotics (IBA), Starościńska 5, 02-516, Warsaw, Poland.
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Mishraki-Berkowitz T, Cohen G, Aserin A, Garti N. Controlling insulin release from reverse hexagonal (H II) liquid crystalline mesophase by enzymatic lipolysis. Colloids Surf B Biointerfaces 2018; 161:670-676. [PMID: 29172155 DOI: 10.1016/j.colsurfb.2017.11.031] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2017] [Revised: 10/29/2017] [Accepted: 11/11/2017] [Indexed: 12/14/2022]
Abstract
In the present study we aimed to control insulin release from the reverse hexagonal (HII) mesophase using Thermomyces lanuginosa lipase (TLL) in the environment (outer TLL) or within the HII cylinders (inner TLL). Two insulin-loaded systems differing by the presence (or absence) of phosphatidylcholine (PC) were examined. In general, incorporation of PC into the HII interface (without TLL) increased insulin release, as a more cooperative system was formed. Addition of TLL to the systems' environments resulted in lipolysis of the HII structure. In the absence of PC, the lipolysis was more dominant and led to a significant increase in insulin release (50% after 8h). However, the presence of PC stabilized the interface, hindering the lipolysis, and therefore no impact on the release profile was detected during the first 8h. Entrapment of TLL within the HII cylinders (with and without PC) drastically increased insulin release in both systems up to 100%. In the presence of PC insulin released faster and the structure was more stable. Consequently, the presence of lipases (inner or outer) both enhanced the destruction of the carrier, and provided sustained release of the entrapped insulin.
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Affiliation(s)
- Tehila Mishraki-Berkowitz
- The Ratner Chair in Chemistry, Casali Institute of Applied Chemistry, The Institute of Chemistry, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Jerusalem 9190401, Israel
| | - Guy Cohen
- Skin Research Institute, Dead-Sea & Arava Science Center, Ein Gedi, Israel
| | - Abraham Aserin
- The Ratner Chair in Chemistry, Casali Institute of Applied Chemistry, The Institute of Chemistry, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Jerusalem 9190401, Israel
| | - Nissim Garti
- The Ratner Chair in Chemistry, Casali Institute of Applied Chemistry, The Institute of Chemistry, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Jerusalem 9190401, Israel.
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