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1.
ACS Appl Mater Interfaces ; 12(20): 22581-22592, 2020 May 20.
Article in English | MEDLINE | ID: mdl-32340452

ABSTRACT

Oral insulin delivery has revolutionized diabetes treatment, but challenges including degradation in the gastrointestinal environment and low permeation across the intestinal epithelium remain. Herein, to overcome these barriers, we developed a novel biodegradable nanocomposite microsphere embedded with metal-organic framework (MOF) nanoparticles. An iron-based MOF nanoparticle (NP) (MIL-100) was first synthesized as a carrier with an insulin loading capacity of 35%. The insulin-loaded MIL-100 nanoparticles modified with sodium dodecyl sulfate (Ins@MIL100/SDS) promoted insulin permeation across Caco-2 monolayer models in vitro. To improve resistance to the gastric acid environment, Ins@MIL100/SDS nanoparticles were embedded into a biodegradable microsphere to construct the nanocomposite delivery system (Ins@MIL100/SDS@MS). The microspheres effectively protected the MOF NPs from rapid degradation under acidic conditions and could release insulin-loaded MOF NPs in the simulated intestinal fluid. After the oral administration of Ins@MIL100/SDS@MS into BALB/c nude mice, increased intestinal absorption of the insulin was detected compared to the oral administration of free insulin or Ins@MIL100/SDS. Furthermore, significantly enhanced plasma insulin levels were obtained for over 6 h after oral administration of Ins@MIL100/SDS@MS into diabetic rats, leading to a remarkably enhanced effect in lowering blood glucose level with a relative pharmacological availability of 7.8%. Thus, the MOF-nanoparticle-incorporated microsphere may provide a new strategy for effective oral protein delivery.


Subject(s)
Diabetes Mellitus, Experimental/drug therapy , Drug Carriers/chemistry , Hypoglycemic Agents/therapeutic use , Insulin, Regular, Pork/therapeutic use , Metal-Organic Frameworks/chemistry , Nanocomposites/chemistry , Administration, Oral , Animals , Biodegradable Plastics/chemistry , Caco-2 Cells , Drug Carriers/administration & dosage , Drug Liberation , Humans , Hypoglycemic Agents/administration & dosage , Hypoglycemic Agents/chemistry , Hypoglycemic Agents/pharmacokinetics , Insulin, Regular, Pork/administration & dosage , Insulin, Regular, Pork/chemistry , Insulin, Regular, Pork/pharmacokinetics , Male , Metal-Organic Frameworks/administration & dosage , Mice, Inbred BALB C , Microspheres , Nanocomposites/administration & dosage , Nanoparticles/administration & dosage , Nanoparticles/chemistry , Polyesters/administration & dosage , Polyesters/chemistry , Polyethylene Glycols/administration & dosage , Polyethylene Glycols/chemistry , Rats, Wistar , Swine
2.
Adv Skin Wound Care ; 33(2): 1-6, 2020 Feb.
Article in English | MEDLINE | ID: mdl-31972587

ABSTRACT

BACKGROUND: Chronic trophic ulcers (CTUs), especially those located over the plantar region, are a leading cause of deformity and disability in patients with leprosy. Despite the various treatment modalities available, CTUs can be chronic and refractory to treatment. The successful use of topical insulin in various types of wounds led researchers to evaluate its safety and efficacy in the treatment of plantar CTUs. METHODS: Forty-two patients who had completed a multidrug treatment for leprosy were recruited and randomized into two groups. In the test group, 23 patients received 10 units (0.1 mL) of topical insulin (Actrapid) in 1 mL of normal saline twice daily over treated areas. The placebo group (n = 19) received topical normal saline only. The primary end point was the proportion of patients with complete wound closure by 12 weeks. Secondary end points included time to healing, wound area reduction, Physician Global Assessment of Efficacy scores, and Dermatology Life Quality Index scores at the end of 12 weeks. RESULTS: The majority of CTUs (80%) were situated over the forefoot; the metatarsal head of the hallux was the most common site (86%). Wound healing was faster (0.61 ± 0.31 vs 0.14 ± 0.42 cm per week, P < .0001), and the number of days to complete healing was significantly shorter in the test group compared with the placebo group (31.5 ± 17.6 vs 44.3 ± 16.2 days, P = .02). The only observed adverse effect in the test group was white granular deposits over the CTU (n = 10). CONCLUSIONS: Topical insulin therapy may be a safe, efficacious, cheap, and easily available treatment option in CTUs among patients with leprosy.


Subject(s)
Foot Ulcer/drug therapy , Hypoglycemic Agents/administration & dosage , Insulin, Regular, Pork/administration & dosage , Leprosy/complications , Administration, Topical , Adult , Chronic Disease , Female , Foot Ulcer/etiology , Humans , Male , Middle Aged , Pilot Projects , Wound Healing
3.
Am J Ther ; 27(1): e42-e51, 2020.
Article in English | MEDLINE | ID: mdl-31876563

ABSTRACT

BACKGROUND: Biosynthetic human insulins and analogs have replaced animal insulins and permitted structural modifications to alter the rate of absorption, duration of action, improve reproducibility of effects, and modulate relative efficacy in various target tissues. Several forms of rapidly acting insulins nearly achieve rapid pharmacokinetics and pharmacodynamics similar to first-phase insulin release. There is need for even faster-acting analogs to mimic normal physiology and improve control of postprandial glycemic excursions. Two biosynthetic insulin analogs have sufficiently long duration of action for use as once-daily basal insulins; controversy persists regarding their respective risks of hypoglycemia and relative glycemic variability. RESULTS: Basal-bolus therapy and insulin pump therapy, including closed-loop automated insulin delivery, require rapid-acting insulin analogs. The longer acting insulins can provide stable, reproducible basal insulin with reduced rates of hypoglycemia, particularly nocturnal hypoglycemia, greater efficacy in reducing mean glucose and glucose variability while increasing time in glucose target range. Inhalable human insulin provides very rapid action. Premixture of rapid-acting analogs with protamine has been useful for some patients with type 2 diabetes. An insulin analog with preferential efficacy at the liver has been developed and tested clinically but not marketed. Current research is aimed at developing even faster-acting insulin analogs. Long-acting basal insulins coformulated with GLP-1 receptor agonists or with a rapidly acting insulin analog have valuable clinical applications. Excipients, chaperones, local heating of the infusion site, and hyaluronidase have also been used to accelerate the absorption of insulin analogs. CONCLUSIONS: Biosynthetic human insulins have radically revolutionized management of both type 1 and type 2 diabetes worldwide. The ability to manipulate the structure and formulation of insulin provides for more physiologic pharmacokinetics and pharmacodynamics, enabling improved glycemic control, reduced risk of hypoglycemia, and reduced rates of long-term complications.


Subject(s)
Diabetes Mellitus, Type 1/drug therapy , Hypoglycemic Agents/therapeutic use , Insulin/analogs & derivatives , Insulin/therapeutic use , Blood Glucose , Diabetes Mellitus, Type 2/drug therapy , Glycated Hemoglobin , Humans , Hypoglycemic Agents/administration & dosage , Hypoglycemic Agents/pharmacokinetics , Insulin/administration & dosage , Insulin/pharmacokinetics , Insulin Infusion Systems , Insulin, Long-Acting/pharmacokinetics , Insulin, Long-Acting/therapeutic use , Insulin, Regular, Pork/administration & dosage
4.
Am J Ther ; 27(1): e24-e29, 2020.
Article in English | MEDLINE | ID: mdl-31703008

ABSTRACT

BACKGROUND: The discovery of insulin has changed dramatically the outcome of patients with type 1 diabetes, giving them the possibility to survive. This is of particular concern due to the fact that type 1 diabetes most frequently occurs in children who were destined to die in ketoacidosis coma. AREAS OF UNCERTAINTY: From insulin discovery to the availability of human insulin and human insulin analogs to be used in diabetes therapy, a series of problems have arisen as the difficulty of insulin purifications, the animal insulin used by the first researches were in fact contaminated by proteins, fats, and other impurities, and the presence of side effects such as allergy, antibodies generation, and lipoatrophy. DATA SOURCE LITERATURE: Data strictly related to the argument have been searched in Pub Med and used. RESULTS: Starting from insulin discovery in 1921 to nowadays, significant efforts have been made by a series of researches to purify animal insulin, discover the molecular structure of human insulin, and develop methods to synthetize human insulin and then insulin analogs. CONCLUSIONS: The history of insulin discovery here reported is fascinating; insulin is a hormone, a product of biotechnology, a field of research that saved and save the life of many diabetic patients.


Subject(s)
Diabetes Mellitus, Type 1/history , Hypoglycemic Agents/history , Insulin/history , Delayed-Action Preparations , Diabetes Mellitus, Type 1/drug therapy , Drug Hypersensitivity/epidemiology , History, 20th Century , Humans , Hypoglycemic Agents/therapeutic use , Insulin/analogs & derivatives , Insulin/therapeutic use , Insulin, Regular, Human/history , Insulin, Regular, Pork/history
5.
Acta Crystallogr D Struct Biol ; 75(Pt 12): 1040-1050, 2019 Dec 01.
Article in English | MEDLINE | ID: mdl-31793898

ABSTRACT

In contrast to twinning by merohedry, the reciprocal lattices of the different domains of non-merohedral twins do not overlap exactly. This leads to three kinds of reflections: reflections with no overlap, reflections with an exact overlap and reflections with a partial overlap of a reflection from a second domain. This complicates the unit-cell determination, indexing, data integration and scaling of X-ray diffraction data. However, with hindsight it is possible to detwin the data because there are reflections that are not affected by the twinning. In this article, the successful solution and refinement of one mineral, one organometallic and two protein non-merohedral twins using a common strategy are described. The unit-cell constants and the orientation matrices were determined by the program CELL_NOW. The data were then integrated with SAINT. TWINABS was used for scaling, empirical absorption corrections and the generation of two different data files, one with detwinned data for structure solution and refinement and a second one for (usually more accurate) structure refinement against total integrated intensities. The structures were solved by experimental phasing using SHELXT for the first two structures and SHELXC/D/E for the two protein structures; all models were refined with SHELXL.


Subject(s)
Aldose-Ketose Isomerases/chemistry , Crystallization/methods , Crystallography, X-Ray/methods , Insulin, Regular, Pork/chemistry , Minerals/chemistry , Models, Molecular
6.
Diabetes Metab Res Rev ; 34(6): e3010, 2018 09.
Article in English | MEDLINE | ID: mdl-29637693

ABSTRACT

BACKGROUND: Oral insulin as a preventive strategy and/or treatment of type 1 diabetes has been the target of much research. Producing oral insulins is a complex and challenging task, with numerous pitfalls, due to physiological, physical, and biochemical barriers. Our aim was to determine the impact of oral insulin on the delicate gut microbiota composition. METHODS: Female nonobese diabetic mice were given oral porcine insulin 2 times a week from 5 weeks of age for 4 weeks, and then subsequently once a week for 21 weeks, or until euthanized. The mice were divided into groups on a gluten-reduced diet or a standard diet. Gut microbiota composition was analysed based on faecal samples, and the type 1 diabetes incidence of the mice was monitored. RESULTS: We observed no influence of the oral porcine insulin on the gut microbiota composition of mice on a gluten-reduced or a standard diet at 9 weeks of age. Also, the administration of oral insulin did not influence the incidence of type 1 diabetes at 30 weeks of age. CONCLUSIONS: Oral porcine insulin does not alter the gut microbiota composition of nonobese diabetic mice on either a gluten-reduced diet or standard diet. Also, the oral porcine insulin did not influence the incidence of type 1 diabetes in the groups.


Subject(s)
Diabetes Mellitus, Experimental/microbiology , Diabetes Mellitus, Type 1/microbiology , Gastrointestinal Microbiome/drug effects , Insulin, Regular, Pork/administration & dosage , Administration, Oral , Animals , Diabetes Mellitus, Experimental/drug therapy , Diabetes Mellitus, Experimental/immunology , Diabetes Mellitus, Experimental/pathology , Diabetes Mellitus, Type 1/drug therapy , Diabetes Mellitus, Type 1/pathology , Dysbiosis/immunology , Dysbiosis/pathology , Feces/microbiology , Female , Insulin, Regular, Pork/adverse effects , Mice , Mice, Inbred NOD , Swine
7.
J Proteomics ; 175: 27-33, 2018 03 20.
Article in English | MEDLINE | ID: mdl-28780057

ABSTRACT

Measurement of insulin and its therapeutic analogs is important in diabetes, hypoglycemia, sports anti-doping and toxicology. Commercial insulin immunoassays fail to detect commonly prescribed insulin analogs. Because of their unique sequences and masses, these analogs are readily measured and distinguished with mass spectrometric (MS) assays. Reviewed here is an insulin mass spectrometric immunoassay (MSIA) that combines micro-scale immunoaffinity capture with sensitive MS detection of insulin and its therapeutic analogs. An antibody reactive to all insulin analogs was used to affinity capture the insulin analogs. Following elution, insulins were detected with MALDI-TOF MS or LC-MS analysis. Isotopic resolution for insulin was achieved for both MS techniques, and several insulin analogs were detected at unique m/z signals. Porcine insulin, spiked in all samples, served as an internal reference standard for quantification. Linear standard curves spanning three orders of magnitude were obtained, with limits of detection of 15pM for the MALDI-TOF MS and 1.5pM for the LC-MS. This insulin assay was capable of detecting and quantifying not only human endogenous insulin, but also most of the therapeutic insulin analogs, which could find use in diagnosis of severe hypoglycemia and in sports anti-doping. SIGNIFICANCE: Insulin replacement therapy consists of injection of long- or fast-acting insulin analogs with slightly modified primary sequences compared to human insulin. Assays that are capable of detecting all insulin analogs are desired, not only for medical management of diabetes and severe hypoglycemia but also for sports anti-doping and toxicology.


Subject(s)
Immunoassay/methods , Insulin/analysis , Mass Spectrometry/methods , Animals , Antibodies , Computational Biology , Diabetes Mellitus/drug therapy , Doping in Sports , Humans , Hypoglycemia/drug therapy , Insulin/analogs & derivatives , Insulin/standards , Insulin, Regular, Pork/analysis , Protein Multimerization , Swine
8.
Intern Med J ; 47(11): 1317-1320, 2017 Nov.
Article in English | MEDLINE | ID: mdl-29105262

ABSTRACT

This study evaluates the clinical efficacy and safety of NovoRapid (insulin aspart) compared to Actrapid™ (human neutral insulin) for diabetic ketoacidosis (DKA). In this retrospective study involving 40 patients, no statistically significant differences were observed between biochemical variables, infusion duration or complications in patients treated with insulin aspart or human neutral insulin. These results support the use of insulin aspart as an effective and safe alternative to human neutral insulin in DKA.


Subject(s)
Diabetic Ketoacidosis/drug therapy , Disease Management , Hypoglycemic Agents/administration & dosage , Insulin Aspart/administration & dosage , Adolescent , Adult , Aged , Aged, 80 and over , Blood Glucose/drug effects , Blood Glucose/metabolism , Cohort Studies , Diabetic Ketoacidosis/blood , Diabetic Ketoacidosis/diagnosis , Female , Humans , Infusions, Intravenous , Insulin, Regular, Pork/administration & dosage , Male , Middle Aged , Retrospective Studies , Treatment Outcome
9.
Am J Physiol Regul Integr Comp Physiol ; 313(1): R19-R28, 2017 07 01.
Article in English | MEDLINE | ID: mdl-28438760

ABSTRACT

The guinea pig is an alternate small animal model for the study of metabolism, including insulin sensitivity. However, only one study to date has reported the use of the hyperinsulinemic euglycemic clamp in anesthetized animals in this species, and the dose response has not been reported. We therefore characterized the dose-response curve for whole body glucose uptake using recombinant human insulin in the adult guinea pig. Interspecies comparisons with published data showed species differences in maximal whole body responses (guinea pig ≈ human < rat < mouse) and the insulin concentrations at which half-maximal insulin responses occurred (guinea pig > human ≈ rat > mouse). In subsequent studies, we used concomitant d-[3-3H]glucose infusion to characterize insulin sensitivities of whole body glucose uptake, utilization, production, storage, and glycolysis in young adult guinea pigs at human insulin doses that produced approximately half-maximal (7.5 mU·min-1·kg-1) and near-maximal whole body responses (30 mU·min-1·kg-1). Although human insulin infusion increased rates of glucose utilization (up to 68%) and storage and, at high concentrations, increased rates of glycolysis in females, glucose production was only partially suppressed (~23%), even at high insulin doses. Fasting glucose, metabolic clearance of insulin, and rates of glucose utilization, storage, and production during insulin stimulation were higher in female than in male guinea pigs (P < 0.05), but insulin sensitivity of these and whole body glucose uptake did not differ between sexes. This study establishes a method for measuring partitioned glucose metabolism in chronically catheterized conscious guinea pigs, allowing studies of regulation of insulin sensitivity in this species.


Subject(s)
Blood Glucose/physiology , Glucose Clamp Technique , Glucose/metabolism , Glucose/pharmacology , Insulin Resistance/physiology , Animals , Blood Glucose/drug effects , Dose-Response Relationship, Drug , Female , Guinea Pigs , Humans , Insulin, Regular, Pork/pharmacology , Male , Species Specificity
10.
Dokl Biol Sci ; 472(1): 15-16, 2017 Jan.
Article in English | MEDLINE | ID: mdl-28429265

ABSTRACT

The influence of insulin preparations (Actrapid and Ransulin) on the glucose and insulin blood level has been studied in patients with diabetes mellitus. It has been shown that comparable changes in the measured parameters are achieved in most patients with oral doses of Ransulin that are two to three times higher than the doses of Actrapid.


Subject(s)
Blood Glucose/metabolism , Diabetes Mellitus/blood , Diabetes Mellitus/drug therapy , Insulin, Regular, Pork/administration & dosage , Insulin, Regular, Pork/pharmacokinetics , Administration, Oral , Female , Humans , Male
12.
Vet Immunol Immunopathol ; 167(3-4): 130-8, 2015 Oct 15.
Article in English | MEDLINE | ID: mdl-26272177

ABSTRACT

Administration of insulin for treatment of diabetes mellitus in dogs can stimulate an immune response, with a proportion of animals developing anti-insulin antibodies (AIA). For an IgG antibody response to occur, this would require B cell presentation of insulin peptides by major histocompatibility complex (MHC) class II molecules, encoded by dog leukocyte antigen (DLA) genes, in order to receive T-cell help for class switching. DLA genes are highly polymorphic in the dog population and vary from breed to breed. The aim of the present study was to evaluate AIA reactivity in diabetic dogs of different breeds and to investigate whether DLA genes influence AIA status. Indirect ELISA was used to determine serological reactivity to insulin in diabetic dogs, treated with either a porcine or bovine insulin preparation. DLA haplotypes for diabetic dogs were determined by sequence-based typing of DLA-DRB1, -DQA1 and -DQB1 loci. Significantly greater insulin reactivity was seen in treated diabetic dogs (n=942) compared with non-diabetic dogs (n=100). Relatively few newly diagnosed diabetic dogs (3/109) were found to be AIA positive, although this provides evidence that insulin autoantibodies might be involved in the pathogenesis of the disease in some cases. Of the diabetic dogs treated with a bovine insulin preparation, 52.3% (182/348) were AIA positive, compared with 12.6% (75/594) of dogs treated with a porcine insulin preparation, suggesting that bovine insulin is more immunogenic. Breeds such as dachshund, Cairn terrier, miniature schnauzer and Tibetan terrier were more likely to develop AIA, whereas cocker spaniels were less likely to develop AIA, compared with crossbreed dogs. In diabetic dogs, DLA haplotype DRB1*0015--DQA1*006--DQB1*023 was associated with being AIA positive, whereas the haplotype DLA-DRB1*006--DQA1*005--DQB1*007 showed an association with being AIA negative. These research findings suggest that DLA genes influence AIA responses in treated diabetic dogs.


Subject(s)
Diabetes Mellitus/veterinary , Dog Diseases/genetics , Dog Diseases/immunology , Histocompatibility Antigens Class I/genetics , Insulin Antibodies/blood , Animals , Cattle , Diabetes Mellitus/genetics , Diabetes Mellitus/immunology , Dog Diseases/drug therapy , Dogs , Insulin/immunology , Insulin/therapeutic use , Insulin, Regular, Pork/immunology , Insulin, Regular, Pork/therapeutic use , Species Specificity
13.
Indian J Pharmacol ; 47(2): 227-9, 2015.
Article in English | MEDLINE | ID: mdl-25878390

ABSTRACT

Insulin is an important agent for the treatment of diabetes mellitus (DM). Allergic reactions to insulin therapy, although rare, have been evident since animal insulin became available for the treatment of DM in 1922. Hypersensitivity to insulin has considerably been reduced with the introduction of human insulin produced by recombinant deoxyribonucleic acid technology. Here, we present a case of Type 2 DM who demonstrated immediate (Type 1) hypersensitivity reaction on the sites of subcutaneous injection of soluble and isophane insulin but insulin glargine was tolerated well and provided good glycemic control.


Subject(s)
Hypersensitivity, Immediate/chemically induced , Insulin Glargine/adverse effects , Insulin, Isophane/adverse effects , Insulin, Regular, Pork/adverse effects , Adult , Blood Glucose/analysis , Female , Humans , Hypersensitivity, Immediate/blood , Hypersensitivity, Immediate/immunology , Immunoglobulin E/blood , Insulin Glargine/administration & dosage , Insulin Glargine/therapeutic use , Insulin, Isophane/administration & dosage , Insulin, Isophane/therapeutic use , Insulin, Regular, Pork/administration & dosage , Insulin, Regular, Pork/therapeutic use , Treatment Outcome
15.
Pharm Res ; 32(6): 2072-85, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25583030

ABSTRACT

PURPOSE: To identify High Molecular Weight Products (HMWP) formed in human insulin formulation during storage. METHODS: Commercial formulation of human insulin was stored at 37°C for 1 year and HMWP was isolated using preparative size exclusion chromatography (SEC) and reverse phase (RP) chromatography. The primary structure of the isolated species was analysed using liquid chromatography mass spectrometry (LC-MS) and tandem mass spectrometry (MS/MS). To test the hypothesis that amino groups of insulin are involved in HMWP formation, the HMWP content of various formulations spiked with amine compounds or formulations of insulin with modified amino groups was measured. RESULTS: More than 20 species of HMWP were observed and 16 species were identified using LC-MS. All identified species were covalent dimers of human insulin linked via A21Asn and B29Lys, formed via the formation of an anhydride intermediate at A21Asn. Two types of HMWP were identified, with the covalent link in the open or closed (succinimidyl) form. Some species also contained single deamidation at B3 or the desPhe(B1)-N-oxalyl-Val(B2) modification. Reduced rate of HMWP formation was observed after addition of L-lysine, L-arginine or piperazine or when insulin analogues with methylated N-terminals and side chain amines and A21Gly mutation were used. Formulations of human insulin without zinc and m-cresol were found to contain a different pool of HMWP. CONCLUSIONS: HMWP formed in formulation of human insulin at pH 7.4 with zinc and m-cresol consists primarily of covalent dimers linked via A21Asn and B29Lys. Insulin formulation properties determine the amount and identity of formed HMWP.


Subject(s)
Drug Contamination , Hypoglycemic Agents/chemistry , Insulin, Regular, Human/chemistry , Insulin, Regular, Pork/chemistry , Amines/chemistry , Amino Acid Sequence , Chemistry, Pharmaceutical , Chromatography, Gel , Chromatography, Reverse-Phase , Cresols/chemistry , Drug Stability , Drug Storage , Humans , Molecular Weight , Protein Multimerization , Protein Stability , Tandem Mass Spectrometry , Temperature , Time Factors , Zinc/chemistry
16.
Metabolism ; 64(2): 330-7, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25468139

ABSTRACT

UNLABELLED: Insulin injected directly into skeletal muscle diffuses rapidly through the interstitial space to cause glucose uptake, but this is blocked in insulin resistance. As glucotoxicity is associated with endothelial dysfunction, the observed hyperglycemia in diet-induced obese dogs may inhibit insulin access to muscle cells, and exacerbate insulin resistance. Here we asked whether interstitial insulin diffusion is reduced in modest hyperglycemia, similar to that induced by a high fat diet. METHODS: During normoglycemic (100 mg/dl) and moderately hyperglycemic (120 mg/dl) clamps in anesthetized canines, sequential doses of insulin were injected into the vastus medialis of one hindlimb; the contra-lateral limb served as a control. Plasma samples were collected and analyzed for insulin content. Lymph vessels of the hind leg were also catheterized, and lymph samples were analyzed as an indicator of interstitial insulin concentration. RESULTS: Insulin injection increased lymph insulin in normoglycemic animals, but not in hyperglycemic animals. Muscle glucose uptake was elevated in response to hyperglycemia, however the insulin-mediated glucose uptake in normoglycemic controls was not observed in hyperglycemia. Modest hyperglycemia prevented intra-muscularly injected insulin from diffusing through the interstitial space reduced insulin-mediated glucose uptake. CONCLUSION: Hyperglycemia prevents the appearance of injected insulin in the interstitial space, thus reducing insulin action on skeletal muscle cells.


Subject(s)
Hyperglycemia/metabolism , Hypoglycemic Agents/pharmacokinetics , Insulin Resistance , Insulin, Regular, Pork/pharmacokinetics , Quadriceps Muscle/metabolism , Absorption, Physiological , Animals , Biological Transport/drug effects , Diffusion , Dogs , Dose-Response Relationship, Drug , Extracellular Space/chemistry , Glucose/metabolism , Glucose Clamp Technique , Hindlimb , Hyperglycemia/blood , Hyperglycemia/drug therapy , Hyperglycemia/physiopathology , Hypoglycemic Agents/administration & dosage , Hypoglycemic Agents/metabolism , Hypoglycemic Agents/therapeutic use , Injections, Intramuscular , Insulin, Regular, Pork/administration & dosage , Insulin, Regular, Pork/analysis , Insulin, Regular, Pork/therapeutic use , Lymph/chemistry , Lymph/drug effects , Male , Quadriceps Muscle/chemistry , Quadriceps Muscle/drug effects , Severity of Illness Index , Tissue Distribution
17.
Anal Bioanal Chem ; 407(11): 3125-35, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25534116

ABSTRACT

This article concerns the development and co-validation of a porcine insulin (pINS) certified reference material (CRM) produced by the National Institute of Metrology, People's Republic of China. Each CRM unit contained about 15 mg of purified solid pINS. The moisture content, amount of ignition residue, molecular mass, and purity of the pINS were measured. Both high-performance liquid chromatography-isotope dilution mass spectrometry and a purity deduction method were used to determine the mass fraction of the pINS. Fifteen units were selected to study the between-bottle homogeneity, and no inhomogeneity was observed. A stability study concluded that the CRM was stable for at least 12 months at -20 °C. The certified value of the CRM was (0.892 ± 0.036) g/g. A co-validation of the CRM was performed among Chinese, Japanese, and Korean laboratories under the framework of the Asian Collaboration on Reference Materials. The co-validation results agreed well with the certified value of the CRM. Consequently, the pINS CRM may be used as a calibration material or as a validation standard for pharmaceutical purposes to improve the quality of pharmaceutical products.


Subject(s)
Chromatography, High Pressure Liquid/standards , Insulin, Regular, Pork/standards , Radioisotope Dilution Technique/standards , Calibration , China , Chromatography, High Pressure Liquid/methods , Hydrolysis , Insulin, Regular, Pork/analysis , Molecular Weight , Reference Standards , Reproducibility of Results
18.
Chronic Dis Inj Can ; 34(2-3): 169-70, 2014 Jul.
Article in English, French | MEDLINE | ID: mdl-24991780

ABSTRACT

As a result of a number of factors, the treatment of insulin-dependent diabetes has moved away from using insulin of beef or pork origin to using recombinant (biosynthetic) insulin preparations. However, some people with type 1 diabetes can manage their diabetes better using animal-sourced insulin. Despite dwindling options and decreased production, animal-sourced insulin (and pork insulin in particular) is still available on the Canadian market. This communication describes the actions taken by Health Canada with respect to the availability of animal insulin.


TITRE: Communication courte -- Le rôle de l'insuline d'origine animale dans le traitement du diabète de type 1 et sa disponibilité RÉSUMÉ: En raison d'un certain nombre de facteurs, on traite désormais davantage le diabète insulinodépendant au moyen de préparations d'insuline recombinante (biosynthétique) qu'au moyen d'insuline d'origine bovine et porcine. Cependant, certaines personnes atteintes du diabète de type 1 parviennent à mieux prendre leur diabète en charge à l'aide d'insuline d'origine animale. Malgré la disponibilité de plus en plus réduite de l'insuline d'origine animale et le déclin de sa production, on peut encore s'en procurer sur le marché canadien, en particulier l'insuline porcine. Cette communication décrit les mesures prises par Santé Canada relativement à la disponibilité de l'insuline d'origine animale.


Subject(s)
Diabetes Mellitus, Type 1/drug therapy , Hypoglycemic Agents/therapeutic use , Insulin, Regular, Pork/therapeutic use , Animals , Canada , Humans , Hypoglycemic Agents/supply & distribution , Insulin, Regular, Pork/supply & distribution , State Medicine , Swine
19.
J Diabetes Sci Technol ; 8(3): 444-52, 2014 May.
Article in English | MEDLINE | ID: mdl-24876604

ABSTRACT

Many experiments conducted in the literature have investigated the effect of microneedles (MNs) on insulin permeation across skin. There are also a number of articles that deal with the effect of MN insertion force in skin. However, there is little known on quantifying the relationship between the effect of MN insertion force and the amount of insulin permeated for given MNs. This issue is addressed in this article. MNs of 1100 µm and 1400 µm are used to conduct in vitro permeability experiments on porcine skin, using insulin. Histological images of MN treated skin are obtained from a microtome and the viscoelastic properties of the skin sample are measured using a rheometer. An in-house insertion force device is utilized that can reproducibly apply a specified force on MNs for a set period of time using compressed air. It is deduced that when porcine skin was pretreated with an applied force of 60.5 N and 69.1 N, the resultant amount of insulin permeated was approximately 3 µg and 25 µg over a 4-hour period for the MNs used. The amount of MN force applied to porcine skin was shown to be related to the amount of insulin permeated. An increase in insertion force increase the amount of insulin permeated. It was also demonstrated that using insufficient force may have reduced or prevented the amount of insulin passing through the skin, regardless of the geometry of the MNs.


Subject(s)
Drug Delivery Systems/instrumentation , Hypoglycemic Agents/administration & dosage , Insulin, Regular, Pork/administration & dosage , Needles , Skin Absorption , Skin/metabolism , Animals , Elasticity , Equipment Design , Hypoglycemic Agents/metabolism , In Vitro Techniques , Injections, Intradermal , Insulin, Regular, Pork/metabolism , Miniaturization , Permeability , Skin/anatomy & histology , Swine , Time Factors , Viscosity
20.
Mol Cell Biochem ; 394(1-2): 59-66, 2014 Sep.
Article in English | MEDLINE | ID: mdl-24825179

ABSTRACT

The purpose of the present study was to determine the activation of porcine insulin promoter (PIP) by three transcription factors: pancreatic and duodenal homeobox 1 (Pdx-1), v-maf musculoaponeurotic fibrosarcoma oncogene (MafA) and neurogenic differentiation 1 (NeuroD1) in non-beta islet cells cultured in vitro. In addition, the expression of the exogenous human islet amyloid polypeptide (hIAPP) gene driving by PIP in porcine kidney 15 (PK15) cells co-transfected with these transcription factors was also examined. In the present study, a series of vectors for gene overexpression were constructed, including pGL3-Pdx-1, pGL3-MafA, pGL3-NeuroD1, pGL3-PIP-LUC and pcDNA3.1-PIP-hIAPP. The dual-luciferase reporter assay showed that the PIP activity was increased in PK15 cells when overexpressing the exogenous transcription factors Pdx-1, MafA and NeuroD1. Introducing the PIP-hIAPP expression vector into PK15 cells combined with exogenous Pdx-1, MafA and NeuroD1 resulted in the efficient expression of hIAPP at the gene level, but not the protein. The current systematic porcine insulin promoter analysis provided the basic information for future utilization of porcine insulin.


Subject(s)
Basic Helix-Loop-Helix Transcription Factors/metabolism , Homeodomain Proteins/metabolism , Insulin, Regular, Pork/metabolism , Islet Amyloid Polypeptide/metabolism , Islets of Langerhans/metabolism , Maf Transcription Factors, Large/metabolism , Nerve Tissue Proteins/metabolism , Promoter Regions, Genetic , Trans-Activators/metabolism , Animals , Basic Helix-Loop-Helix Transcription Factors/genetics , Cell Line, Tumor , Feasibility Studies , Gene Expression Regulation , Homeodomain Proteins/genetics , Humans , Insulin, Regular, Pork/genetics , Islet Amyloid Polypeptide/genetics , Maf Transcription Factors, Large/genetics , Nerve Tissue Proteins/genetics , RNA, Messenger/metabolism , Swine , Swine, Miniature , Trans-Activators/genetics , Transcriptional Activation , Transfection
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