oxadiazoles and Diabetes-Mellitus--Type-1

To screen several antiviral drugs systematically for their efficacy against type B coxsackieviruses.. Ten drugs with different antiviral mechanisms were analysed for their efficacy against prototype strains of type B coxsackieviruses in A549 cells. Cell viability was quantified in fixed cells using a colorimetric assay. Median effective dose was interpolated from the triplicated experiments and the dose-response curves were generated for each drug-virus combination. Drug cytotoxicity was similarly quantified and selectivity indices calculated.. Hizentra, pleconaril, fluoxetine, norfluoxetine, ribavirin, favipiravir, and guanidine hydrochloride were able to abrogate infection by all tested viruses, with the exception of complete inefficacy of pleconaril against coxsackievirus B3 and favipiravir against coxsackievirus B2. The effective doses for Hizentra, enviroxime, ribavirin, favipiravir, and pleconaril were clearly below their therapeutic serum concentrations, while the effective concentrations of fluoxetin, norfluoxetine and itraconazole exceeded their therapeutic serum concentrations. Lovastatin and azithromycin did not efficiently block type B coxsackieviruses.. Hizentra, enviroxime, pleconaril, ribavirin, and favipiravir are effective against type B coxsackieviruses in vitro in their therapeutic serum concentrations. These antiviral drugs are therefore attractive candidates for type 1 diabetes prevention/treatment trials. They can also be used in other clinical conditions caused by type B coxsackieviruses.

Topics: A549 Cells; Amides; Antiviral Agents; Azithromycin; Benzimidazoles; Coxsackievirus Infections; Diabetes Mellitus, Type 1; Drug Repositioning; Enterovirus B, Human; Fluoxetine; Guanidine; Humans; Immunoglobulin G; Lovastatin; Oxadiazoles; Oxazoles; Oximes; Pyrazines; Ribavirin; Sulfonamides

A Picornavirus (Ljungan virus [LV]) originally found in bank voles has been associated with type 1 diabetes (T1D) in its wild rodent reservoir, but also associated with T1D in a laboratory rat model for the disease, the diabetes prone (DP) Bio Breeding (BB) rat. Successful treatment of diabetes in this rat model, using experimental antiviral compounds directed against picornavirus, has been reported. In the present study we show significant clinical response in DP-BB rats using antiviral compounds available for human use (Pleconaril, Efavirenz, and Ribavirin). Presence of LV picornavirus antigen has been detected in islets of Langerhans from both human and the T1D rat model with clear morphological similarity. Based on these data it would be of interest to test antiviral treatment in patients with newly diagnosed T1D. Successful outcome will offer both proof of concept regarding the role of virus involvement in the disease and possibly a first generation treatment interrupting a persistent infection and stopping

Topics: Adult; Alkynes; Animals; Antiviral Agents; Benzoxazines; Cyclopropanes; Diabetes Mellitus, Type 1; Humans; Male; Oxadiazoles; Oxazoles; Proof of Concept Study; Rats; Ribavirin

Blockade of IFN-α but not IFN-β signaling using either an antibody or a selective S1PR1 agonist, CYM-5442, prevented type 1 diabetes (T1D) in the mouse

Topics: Animals; Diabetes Mellitus, Type 1; Disease Models, Animal; Disease Progression; Indans; Insulin; Insulin-Secreting Cells; Interferon-alpha; Islets of Langerhans; Mice; Oxadiazoles; Prediabetic State; Receptors, Immunologic; Receptors, Lysosphingolipid; Signal Transduction; Sphingosine-1-Phosphate Receptors; T-Lymphocytes

The effects of LV in two different species, CD-1 mice, without a genetic disposition for diabetes, and BB rats prone to T1D were examined. Male CD-1 mice that had been exposed to LV in utero developed a type 2-like diabetes with increased blood glucose, insulin levels and epididymal fat at the age of 10-15 weeks. Combination therapy including LV-antiserum and an antiviral drug, Pleconaril, significantly reduced the levels of blood glucose and insulin and the amount of abdominal fat. In BB rats, LV has been found in both prediabetic- and diabetic diabetes-prone rats, as well as in diabetes-resistant rats. To evaluate whether the presence of LV has any influence on the onset of T1D, prediabetic BB rats were treated with an antiserum against LV or a combination of the antiviral drugs Pleconaril and Ribavirin. In the group treated with antiviral drugs, the onset was significantly delayed. These results indicate that the presence of LV can be involved in the pathogenesis of diabetes in these animal models.

Topics: Animals; Antibodies, Viral; Antiviral Agents; Diabetes Mellitus, Type 1; Drug Therapy, Combination; Humans; Immunologic Factors; Mice; Oxadiazoles; Oxazoles; Parechovirus; Picornaviridae Infections; Rats; Rats, Inbred BB; Ribavirin

1. The present study evaluated the effect of diabetes, hypercholesterolaemia and their combination on the contribution of nitric oxide (NO) and endothelium-derived hyperpolarizing factor (EDHF) to relaxation of rat isolated aortic rings and the potential contribution of oxidant stress to the disturbance of endothelial function. 2. Thoracic aortic rings from control, diabetic, hypercholesterolaemic and diabetic plus hypercholesterolaemic rats were suspended in organ baths for tension recording. Generation of superoxide by the aorta was measured using lucigenin-enhanced chemiluminescence. 3. The maximal response to acetylcholine (ACh) was significantly reduced in diabetic or hypercholesterolaemic rats compared with control rats. In rats with diabetes plus hypercholesterolaemia, both the sensitivity and maximal response to ACh was impaired. In control rats, the response to ACh was abolished by the NO synthase inhibitor N(G)-nitro-L-arginine (L-NNA) or inhibition of soluble guanylate cyclase with 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ). In contrast, in rats with diabetes, hypercholesterolaemia or both, relaxation to ACh was resistant to inhibition by L-NNA or ODQ, but abolished by additional inhibition of K(Ca) channels with charybdotoxin plus apamin. 4. The generation of superoxide was not significantly enhanced in aortic rings from either diabetic or hypercholesterolaemic rats, but was significantly increased in aortic rings from rats with diabetes plus hypercholesterolaemia. 5. These results suggest that when diabetes and hypercholesterolaemia impair endothelium-dependent relaxation, due to a diminished contribution from NO, a compensatory contribution of EDHF to endothelium-dependent relaxation of the aorta is revealed. The attenuation of NO-mediated relaxation, at least in the presence of both diabetes and hypercholesterolaemia, is associated with enhanced superoxide generation.

Topics: Acetylcholine; Animals; Aorta, Thoracic; Apamin; Biological Factors; Blood Glucose; Body Weight; Charybdotoxin; Cholesterol; Cyclooxygenase Inhibitors; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 1; Disease Models, Animal; Dose-Response Relationship, Drug; Enzyme Inhibitors; Guanylate Cyclase; Hypercholesterolemia; Indomethacin; Male; Nitric Oxide; Nitric Oxide Synthase; Nitroarginine; Nitroprusside; Oxadiazoles; Oxidative Stress; Potassium Channel Blockers; Potassium Channels, Calcium-Activated; Quinoxalines; Rats; Rats, Sprague-Dawley; Receptors, Cytoplasmic and Nuclear; Soluble Guanylyl Cyclase; Superoxides; Vasodilation; Vasodilator Agents

Enterovirus infections of the pancreatic islets are believed to trigger or precipitate the near total destruction of beta-cells that constitutes type 1 diabetes (T1D). This study investigated the ability of an anti-picornaviral compound, pleconaril, to block the replication of two beta-cell tropic Coxsackie B4 virus (CBV-4) strains in isolated human islets. The two strains, VD2921 and V89 4557, with demonstrated abilities to cause non-lytic persistence or lytic infection, respectively, in islets, represented two different potential mechanisms behind virus-induced T1D. The virus replication in the islets was studied with and without addition of pleconaril. In addition, islet morphology was studied every day. To test the effects of pleconaril and/or DMSO on the beta-cells' insulin secretion, glucose perifusions were performed on treated and untreated islets. Virus titrations showed a clear reduction of the replication of both strains after pleconaril treatment. The VD2921 strain was inhibited to undetectable levels. The V89 4557 strain, however, showed an initial reduction of titers but virus titers then increased despite the addition of a second dose of pleconaril. This incomplete inhibition of viral replication suggested the existence of a resistant subtype within this strain. Pleconaril treatment reduced the beta-cells' insulin secretion in response to glucose stimulation in some experiments and induced slight morphological changes to the islets compared to untreated controls. In summary, pleconaril reduced the replication of the two beta-cell tropic CBV-4 strains in human islets. However, genetic differences between these strains influenced the effectiveness of pleconaril treatment. This stresses the importance of using multiple viral strains in antiviral tests.

Topics: Antiviral Agents; Cells, Cultured; Coxsackievirus Infections; Cytopathogenic Effect, Viral; Diabetes Mellitus, Type 1; Enterovirus B, Human; Humans; Insulin; Islets of Langerhans; Oxadiazoles; Oxazoles

Pregnant women with diabetes mellitus have a higher incidence of adverse pregnancy outcomes. Vascular, and in particular, endothelial function may be significantly modified in diabetes resulting in impaired endothelium-dependent relaxation. This study aims to investigate endothelium-dependent relaxation in pregnant women with pre-existing type I diabetes mellitus.. Small arteries (mean luminal diameter approximately 295 microm) were isolated from biopsies of subcutaneous fat from pregnant women with pre-existing type I diabetes mellitus, non-diabetic pregnant women, and non-diabetic non-pregnant women. Endothelial and smooth muscle function were determined using wire myography, and the contributions of nitric oxide, vasodilator prostanoid and endothelial hyperpolarisation were studied using specific inhibitors.. Arteries obtained from the diabetic pregnant women did not demonstrate any difference in either endothelial or smooth muscle function when compared with non-diabetic pregnant women. The contribution of nitric oxide to endothelium-dependent relaxation was approximately 20% in the pregnant women regardless of whether they were diabetic, and approximately 11% in the non-pregnant women. Endothelial hyperpolarisation appeared to contribute largely to vasorelaxation in human subcutaneous arteries, and was at least twice that of nitric oxide in pregnant women and fivefold greater in non-pregnant women.. This study provides evidence that pregnant women with well-controlled pre-existing type 1 diabetes mellitus have both normal endothelial and smooth muscle function. Endothelium-dependent hyperpolarisation appears to play a large role in vascular relaxation in human subcutaneous resistance arteries. This study suggests that the problems associated with diabetic pregnancies are unlikely to be due to vascular dysfunction.

Topics: Adult; Analysis of Variance; Arteries; Cyclooxygenase Inhibitors; Diabetes Mellitus, Type 1; Endothelium, Vascular; Enzyme Inhibitors; Female; Humans; Indomethacin; Muscle Relaxation; Muscle, Smooth, Vascular; NG-Nitroarginine Methyl Ester; Nitric Oxide; Oxadiazoles; Pregnancy; Pregnancy in Diabetics; Vasoconstriction; Vasodilator Agents