scholarly journals Novel Formulations of C-Peptide with Long-Acting Therapeutic Potential for Treatment of Diabetic Complications

Pharmaceutics ◽  
2019 ◽  
Vol 11 (1) ◽  
pp. 27 ◽  
Author(s):  
Natalia Zashikhina ◽  
Vladimir Sharoyko ◽  
Mariia Antipchik ◽  
Irina Tarasenko ◽  
Yurii Anufrikov ◽  
...  
Keyword(s):  
Therapeutic Potential ◽  
Ex Vivo ◽  
Random Copolymers ◽  
C Peptide ◽  
Hek 293 ◽  
Physiological Conditions ◽  
293 Cells ◽  
Long Acting ◽  
Polypeptide Structure ◽  
Initial Drug

The development and application of novel nanospheres based on cationic and anionic random amphiphilic polypeptides with prolonged stability were proposed. The random copolymers, e.g., poly(l-lysine-co-d-phenylalanine) (P(Lys-co-dPhe)) and poly(l-glutamic acid-co-d-phenylalanine) (P(Glu-co-dPhe)), with different amount of hydrophilic and hydrophobic monomers were synthesized. The polypeptides obtained were able to self-assemble into nanospheres. Such characteristics as size, PDI and ζ-potential of the nanospheres were determined, as well as their dependence on pH was also studied. Additionally, the investigation of their biodegradability and cytotoxicity was performed. The prolonged stability of nanospheres was achieved via introduction of d-amino acids into the polypeptide structure. The cytotoxicity of nanospheres obtained was tested using HEK-293 cells. It was proved that no cytotoxicity up to the concentration of 500 µg/mL was observed. C-peptide delivery systems were realized in two ways: (1) peptide immobilization on the surface of P(Glu-co-dPhe) nanospheres; and (2) peptide encapsulation into P(Lys-co-dPhe) systems. The immobilization capacity and the dependence of C-peptide encapsulation efficiency, as well as maximal loading capacity, on initial drug concentration was studied. The kinetic of drug release was studied at model physiological conditions. Novel formulations of a long-acting C-peptide exhibited their effect ex vivo by increasing activity of erythrocyte Na+/K+-adenosine triphosphatase.

Composition and function of macroencapsulated human embryonic stem cell-derived implants: comparison with clinical human islet cell grafts

2014 ◽  
Vol 307 (9) ◽  
pp. E838-E846 ◽  
Author(s):  
Evi Motté ◽  
Edit Szepessy ◽  
Krista Suenens ◽  
Geert Stangé ◽  
Myriam Bomans ◽  
...  
Keyword(s):  
Islet Cell ◽  
Endocrine Cells ◽  
Large Scale ◽  
Therapeutic Potential ◽  
Ex Vivo ◽  
Embryonic Stem ◽  
Human Islet ◽  
Insulin Biosynthesis ◽  
Β Cells ◽  
C Peptide

β-Cells generated from large-scale sources can overcome current shortages in clinical islet cell grafts provided that they adequately respond to metabolic variations. Pancreatic (non)endocrine cells can develop from human embryonic stem (huES) cells following in vitro derivation to pancreatic endoderm (PE) that is subsequently implanted in immune-incompetent mice for further differentiation. Encapsulation of PE increases the proportion of endocrine cells in subcutaneous implants, with enrichment in β-cells when they are placed in TheraCyte-macrodevices and predominantly α-cells when they are alginate-microencapsulated. At posttransplant (PT) weeks 20–30, macroencapsulated huES implants presented higher glucose-responsive plasma C-peptide levels and a lower proinsulin-over-C-peptide ratio than human islet cell implants under the kidney capsule. Their ex vivo analysis showed the presence of single-hormone-positive α- and β-cells that exhibited rapid secretory responses to increasing and decreasing glucose concentrations, similar to isolated human islet cells. However, their insulin secretory amplitude was lower, which was attributed in part to a lower cellular hormone content; it was associated with a lower glucose-induced insulin biosynthesis, but not with lower glucagon-induced stimulation, which together is compatible with an immature functional state of the huES-derived β-cells at PT weeks 20–30. These data support the therapeutic potential of macroencapsulated huES implants but indicate the need for further functional analysis. Their comparison with clinical-grade human islet cell grafts sets references for future development and clinical translation.

Abstract 12236: A Novel Particulate Guanylyl Cyclase B Agonist With Therapeutic Potential Targeting Fibrosis via cGMP Generation for Cardiorenal Disease

Circulation ◽  
2015 ◽  
Vol 132 (suppl_3) ◽  
Author(s):  
S. J Sangaralingham ◽  
Brenda K Huntley ◽  
Tomoko Ichiki ◽  
Gerald E Harders ◽  
John C Burnett
Keyword(s):  
Guanylyl Cyclase ◽  
Therapeutic Potential ◽  
Human Fibroblasts ◽  
Active Form ◽  
Hek 293 ◽  
Hek Cells ◽  
293 Cells ◽  
No Activation

Introduction: Fibrosis is a hallmark of cardiorenal diseases, including heart failure, for which there are few effective therapies. C-type natriuretic peptide (CNP) is a cardiorenal-derived peptide whose mature active form, CNP-22, possesses potent anti-fibrotic actions through the activation of guanylyl cyclase receptor B (GC-B) and its second messenger, cGMP. However, CNP-22’s therapeutic potential is limited due to its short half-life. We recently identified a 53 amino acid (AA) peptide, CNP-53, whose structure consists of CNP-22 with an additional 31 AA on the N-terminus. Herein, we investigated the cGMP generating actions of CNP-53 (compared to CNP-22) in vivo and in vitro, with the goal of advancing a potential anti-fibrotic strategy for cardiorenal disease. Hypotheses: We hypothesized that CNP-53 would elevate circulating CNP levels as well as have greater cGMP activating actions compared to CNP-22 in vivo. We also hypothesized that CNP-53 would stimulate GC-B specific cGMP production in vitro. Methods: In vivo, two groups of anesthetized normal rats (n=8) received a 75-minute intravenous infusion of an equimolar dose of CNP-53 or CNP-22. Mean arterial pressure (MAP), plasma CNP and plasma and urinary cGMP were assessed. In vitro, HEK 293 cells over-expressing GC-A and GC-B and human fibroblasts (hFs), where GC-B is abundant, were stimulated with CNP-53 or CNP-22 for 10 minutes at a dose of (10-8M). Data are mean ± SE, *p<0.05. Results: In vivo, plasma CNP (CNP-53: 311±66, CNP-22: 153±16 pg/ml*) and cGMP (CNP-53: 21±2, CNP-22: 11±1 pmol/ml*) and urinary cGMP excretion (CNP-53: 75±4, CNP-22: 38±1 pmol/min*) were greater with CNP-53 infusion than CNP-22. MAP was similar between the 2 groups (CNP-53: 85±2, CNP-22: 88±4 mmHg). In vitro, both CNP-53 and CNP-22 activated cGMP in GC-B HEK cells and in hFs, with no activation of cGMP in GC-A HEK cells. Conclusions: These findings demonstrate that CNP-53 is superior to CNP-22 in activating cGMP in vivo, without inducing hypotension. Additionally, CNP-53 is a GC-B specific cGMP activating peptide that potently increases cGMP in hFs. Thus, CNP-53 may represent a novel first in class GC-B agonist with therapeutic potential targeting fibrosis and preventing the progression of cardiorenal disease.

Abstract 13311: Cardiac SIRT1 Deficiency Sensitizes Myocardium to Ischemia and Reperfusion Injury

Circulation ◽  
2014 ◽  
Vol 130 (suppl_2) ◽  
Author(s):  
Jinli Wang ◽  
Yina Ma ◽  
Wanqing Sun ◽  
George Techiryan ◽  
Yanqing Wang ◽  
...  
Keyword(s):  
Infarct Size ◽  
Therapeutic Potential ◽  
Ex Vivo ◽  
Heart Function ◽  
Interleukin 1 ◽  
Left Ventricular ◽  
Sirtuin 1 ◽  
Ischemia And Reperfusion ◽  
Ischemia And Reperfusion Injury ◽  
Physiological Conditions

Introduction: A “longevity” gene, sirtuin 1 (SIRT1) is a conserved NAD + -dependent protein deacetylase that regulates life span extension. We have reported that SIRT1 is down-regulated in the aged heart which shows larger infarct size and deteriorative heart function during ischemia and reperfusion (I/R) compared with that of young heart. Hypothesis: Cardiac specific SIRT1 deficiency could increase the sensitivity of heart to ischemic insults caused by ischemia and reperfusion. Methods: Male SIRT1 flox/flox mice and tamoxifen-inducible, cardiac-specific SIRT1 KO mice were subjected to I/R, which were induced by occluding the left anterior descending coronary (LAD) and subsequent releasing it. Langendorff-perfused heart model was used to monitor the heart function during I/R. Results: Adult cardiac-specific SIRT1 KO demonstrated significant cardiac hypertrophy, fibrosis and macrophage infiltration under normal physiological conditions versus the SIRT1 flox/flox hearts by immunohistochemical staining (all p<0.05). The cardiac functions measured by the pressure-volume loop remained normal in SIRT1 KO mice as compared with SIRT1 flox/flox mice under physiological conditions. The ex vivo heart perfusion results showed that the heart rate-left ventricular developed pressure product in SIRT1 KO hearts was decreased by 30% versus the SIRT1 flox/flox hearts (p<0.05), and the infarct size of SIRT1 KO hearts was 1.7-fold larger than that of SIRT1 flox/flox hearts (p<0.05). The immunoblotting data demonstrated that SIRT1 KO hearts had impaired responsive activation of AMP-activated protein kinase (AMPK) signaling during I/R versus the SIRT1 flox/flox hearts. Furthermore, real-time qRT-PCR showed that cardiac SIRT1 KO resulted in up-regulation of pro-inflammatory cytokines, including tumor necrosis factor (TNF)-α, interleukin-1 β and growth differentiation factor15 (GDF15), as well as a heart failure marker ANP (atrial natriuretic peptide) versus SIRT1 flox/flox hearts during I/R. Conclusions: SIRT1 plays a vital role in regulation of myocardial infarction, heart function and inflammation induced by I/R in the heart. SIRT1 specific agonists may have therapeutic potential for treatment of ischemic heart disease.

CLL-1 Is a Potential Target for the Treatment of Acute Myeloid Leukemia.

Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 2839-2839
Author(s):  
Wouter Korver ◽  
Xiaoxian Zhao ◽  
Shweta Singh ◽  
Eric D. Hsi ◽  
Arie Abo
Keyword(s):  
Flow Cytometry ◽  
Therapeutic Potential ◽  
Ex Vivo ◽  
Normal Tissues ◽  
B Lymphoma Cells ◽  
293 Cells ◽  
Complement Dependent Cytotoxicity ◽  
Xenograft Models

Abstract CLL-1 (C-type Lectin-Like Molecule-1) is an inhibitory receptor expressed on myeloid cells. We have generated a series of monoclonal antibodies (mAbs) against CLL-1 and used these mAbs to assess expression of the receptor on normal and AML cells and their therapeutic potential in in vitro and ex vivo cytotoxicity assays. By Immunohistochemistry, normal tissues lacked expression of CLL-1, with the exception of spleen. Using flow cytometry, expression was demonstrated on monocytes, granulocytes and dendritic cells, but not on lymphocytes and platelets. Tissue micro-arrays revealed CLL-1 expression in 97.3% (37/38) of AML cases. Flow cytometry of AML blasts demonstrated expression of CLL-1 on 81% (17/21) of patient samples. No detectable expression was detected in ALL blasts (n=5). Selected anti-CLL-1 mAbs mediated dose-dependent Complement Dependent Cytotoxicity (CDC) in various AML-derived cell lines, while no cytotoxicity was observed in CLL-1 negative K562 (CML) or CA46 (B lymphoma) cells. Human embryonic kidney 293 cells only became susceptible to anti-CLL-1 mAb mediated killing after transfection with CLL-1, demonstrating specificity. Furthermore, anti-CLL-1 mAbs showed CDC activity against all AML blasts tested in ex vivo assays (n=10), while no activity was observed against ALL blasts. Our results demonstrate restricted expression of CLL-1 on cells from myeloid origin and AML blasts and specific cytotoxic activity in in vitro and ex vivo assays. We are currently undertaking xenograft models to evaluate the therapeutic potential of these mAbs in vivo.

Involvement of Heme Oxygenase-1 in Neuropsychiatric and Neurodegenerative Diseases

2018 ◽  
Vol 24 (20) ◽  
pp. 2283-2302 ◽  
Author(s):  
Vivian B. Neis ◽  
Priscila B. Rosa ◽  
Morgana Moretti ◽  
Ana Lucia S. Rodrigues
Keyword(s):  
Neurodegenerative Diseases ◽  
Heme Oxygenase ◽  
Therapeutic Potential ◽  
Redox Homeostasis ◽  
Antioxidant Defenses ◽  
Heme Oxygenase 1 ◽  
Physiological Conditions ◽  
And Oxidative Stress ◽  
Defensive Mechanism

Heme oxygenase (HO) family catalyzes the conversion of heme into free iron, carbon monoxide and biliverdin. It possesses two well-characterized isoforms: HO-1 and HO-2. Under brain physiological conditions, the expression of HO-2 is constitutive, abundant and ubiquitous, whereas HO-1 mRNA and protein are restricted to small populations of neurons and neuroglia. HO-1 is an inducible enzyme that has been shown to participate as an essential defensive mechanism for neurons exposed to oxidant challenges, being related to antioxidant defenses in certain neuropathological conditions. Considering that neurodegenerative diseases (Alzheimer’s Disease (AD), Parkinson’s Disease (PD) and Multiple Sclerosis (MS)) and neuropsychiatric disorders (depression, anxiety, Bipolar Disorder (BD) and schizophrenia) are associated with increased inflammatory markers, impaired redox homeostasis and oxidative stress, conditions that may be associated with alterations in HO-levels/activity, the purpose of this review is to present evidence on the possible role of HO-1 in these Central Nervous System (CNS) diseases. In addition, the possible therapeutic potential of targeting brain HO-1 is explored in this review.

Design and Evaluation of Long Acting Biodegradable PLGA Microspheres for Ocular Drug Delivery

2019 ◽  
Vol 10 ◽  
Author(s):  
Anjali Pandya ◽  
Rajani Athawale ◽  
Durga Puro ◽  
Geeta Bhagwat
Keyword(s):  
Particle Size ◽  
Drug Release ◽  
Degradation Products ◽  
Ex Vivo ◽  
Research Work ◽  
Entrapment Efficiency ◽  
Rational Approach ◽  
Plga Microspheres ◽  
Long Acting

Background: The research work involves development of PLGA biodegradable microspheres loaded with dexamethasome for intraocular delivery. Objective: To design and evaluate long acting PLGA microspheres for ocular delivery of dexamethasone. Method: Present formulation involves the development of long acting dexamethasone loaded microspheres composed of a biodegradable controlled release polymer, Poly(D, L- lactide-co-glycolide) (PLGA), for the treatment of posterior segment eye disorders intravitreally. PLGA with monomer ratio of 50:50 of lactic acid to glycolic acid was used to achieve a drug release up to 45 days. Quality by Design approach was utilized for designing the experiments. Single emulsion solvent evaporation technique along with high pressure homogenization was used to facilitate formation of microspheres. Results: Particle size evaluation, drug content and drug entrapment efficiency were determined for the microspheres. Particle size and morphology was observed using Field Emission Gun-Scanning Electron Microscopy (FEG-SEM) and microspheres were in the size range of 1-5 μm. Assessment of drug release was done using in vitro studies and transretinal permeation was observed by ex vivo studies using goat retinal tissues. Conclusion: Considering the dire need for prolonged therapeutic effect in diseases of the posterior eye, an intravitreal long acting formulation was designed. Use of biodegradable polymer with biocompatible degradation products was a rational approach to achieve this aim. Outcome from present research shows that developed microspheres would provide a long acting drug profile and reduce the frequency of administration thereby improving patient compliance.

scholarly journals Coptisine Attenuates Diabetes—Associated Endothelial Dysfunction through Inhibition of Endoplasmic Reticulum Stress and Oxidative Stress

Molecules ◽  
2021 ◽  
Vol 26 (14) ◽  
pp. 4210
Author(s):  
Yan Zhou ◽  
Chunxiu Zhou ◽  
Xutao Zhang ◽  
Chi Teng Vong ◽  
Yitao Wang ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Risk Factors ◽  
Endoplasmic Reticulum ◽  
Er Stress ◽  
Vascular Function ◽  
Inflammatory Responses ◽  
Therapeutic Potential ◽  
Ex Vivo ◽  
Diabetic Mice ◽  
And Oxidative Stress

Coptisine is the major bioactive protoberberine alkaloid found in Rhizoma Coptidis. Coptisine reduces inflammatory responses and improves glucose tolerance; nevertheless, whether coptisine has vasoprotective effect in diabetes is not fully characterized. Conduit arteries including aortas and carotid arteries were obtained from male C57BL/6J mice for ex vivo treatment with risk factors (high glucose or tunicamycin) and coptisine. Some arterial rings were obtained from diabetic mice, which were induced by high-fat diet (45% kcal% fat) feeding for 6 weeks combined with a low-dose intraperitoneal injection of streptozotocin (120 mg/kg). Functional studies showed that coptisine protected endothelium-dependent relaxation in aortas against risk factors and from diabetic mice. Coptisine increased phosphorylations of AMPK and eNOS and downregulated the endoplasmic reticulum (ER) stress markers as determined by Western blotting. Coptisine elevates NO bioavailability and decreases reactive oxygen species level. The results indicate that coptisine improves vascular function in diabetes through suppression of ER stress and oxidative stress, implying the therapeutic potential of coptisine to treat diabetic vasculopathy.

scholarly journals Species-Specific Regulation of TRPM2 by PI(4,5)P2 via the Membrane Interfacial Cavity

2021 ◽  
Vol 22 (9) ◽  
pp. 4637
Author(s):  
Daniel Barth ◽  
Andreas Lückhoff ◽  
Frank J. P. Kühn
Keyword(s):  
Amino Acid Residues ◽  
Hek 293 ◽  
Complete Inactivation ◽  
293 Cells ◽  
Activation Mechanisms ◽  
Specific Regulation ◽  
Species Specific ◽  
Inside Out ◽  
Positively Charged

The human apoptosis channel TRPM2 is stimulated by intracellular ADR-ribose and calcium. Recent studies show pronounced species-specific activation mechanisms. Our aim was to analyse the functional effect of phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2), commonly referred to as PIP2, on different TRPM2 orthologues. Moreover, we wished to identify the interaction site between TRPM2 and PIP2. We demonstrate a crucial role of PIP2, in the activation of TRPM2 orthologues of man, zebrafish, and sea anemone. Utilizing inside-out patch clamp recordings of HEK-293 cells transfected with TRPM2, differential effects of PIP2 that were dependent on the species variant became apparent. While depletion of PIP2 via polylysine uniformly caused complete inactivation of TRPM2, restoration of channel activity by artificial PIP2 differed widely. Human TRPM2 was the least sensitive species variant, making it the most susceptible one for regulation by changes in intramembranous PIP2 content. Furthermore, mutations of highly conserved positively charged amino acid residues in the membrane interfacial cavity reduced the PIP2 sensitivity in all three TRPM2 orthologues to varying degrees. We conclude that the membrane interfacial cavity acts as a uniform PIP2 binding site of TRPM2, facilitating channel activation in the presence of ADPR and Ca2+ in a species-specific manner.

scholarly journals Ex vivo evaluation of a multilayered sealant patch for watertight dural closure: cranial and spinal models

2021 ◽  
Vol 32 (8) ◽  
Author(s):  
A. Kinaci ◽  
S. van Thoor ◽  
S. Redegeld ◽  
M. Tooren ◽  
T. P. C. van Doormaal
Keyword(s):  
Ex Vivo ◽  
Resistance Test ◽  
Burst Pressure ◽  
Cerebrospinal Fluid Leakage ◽  
Computer Assisted ◽  
Dural Defect ◽  
Test Results ◽  
Physiological Conditions ◽  
Dural Attachment ◽  
The Mean

AbstractCerebrospinal fluid leakage is a frequent complication after cranial and spinal surgery. To prevent this complication and seal the dura watertight, we developed Liqoseal, a dural sealant patch comprising a watertight polyesterurethane layer and an adhesive layer consisting of poly(DL-lactide-co-ε-caprolactone) copolymer and multiarmed N-hydroxylsuccinimide functionalized polyethylene glycol. We compared acute burst pressure and resistance to physiological conditions for 72 h of Liqoseal, Adherus, Duraseal, Tachosil, and Tisseel using computer-assisted models and fresh porcine dura. The mean acute burst pressure of Liqoseal in the cranial model (145 ± 39 mmHg) was higher than that of Adherus (87 ± 47 mmHg), Duraseal (51 ± 42 mmHg) and Tachosil (71 ± 16 mmHg). Under physiological conditions, cranial model resistance test results showed that 2 of 3 Liqoseal sealants maintained dural attachment during 72 hours as opposed to 3 of 3 for Adherus and Duraseal and 0 of 3 for Tachosil. The mean burst pressure of Liqoseal in the spinal model (233 ± 81 mmHg) was higher than that of Tachosil (123 ± 63 mmHg) and Tisseel (23 ± 16 mmHg). Under physiological conditions, spinal model resistance test results showed that 2 of 3 Liqoseal sealants maintained dural attachment for 72 hours as opposed to 3 of 3 for Adherus and 0 of 3 for Duraseal and Tachosil. This novel study showed that Liqoseal is capable of achieving a strong watertight seal over a dural defect in ex vivo models.

scholarly journals Preliminary Study on Pasta Samples Characterized in Antioxidant Compounds and Their Biological Activity on Kidney Cells

Nutrients ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 1131 ◽  
Author(s):  
Federico Di Marco ◽  
Francesco Trevisani ◽  
Pamela Vignolini ◽  
Silvia Urciuoli ◽  
Andrea Salonia ◽  
...  
Keyword(s):  
Indoleacetic Acid ◽  
Antioxidant Properties ◽  
Antioxidant Compounds ◽  
Kidney Cells ◽  
Hek 293 ◽  
293 Cells ◽  
High Concentrations ◽  
Β Carotene ◽  
Egg Pasta

Pasta is one of the basic foods of the Mediterranean diet and for this reason it was chosen for this study to evaluate its antioxidant properties. Three types of pasta were selected: buckwheat, rye and egg pasta. Qualitative–quantitative characterization analyses were carried out by HPLC-DAD to identify antioxidant compounds. The data showed the presence of carotenoids such as lutein and polyphenols such as indoleacetic acid, (carotenoids from 0.08 to 0.16 mg/100 g, polyphenols from 3.7 to 7.4 mg/100 g). To assess the effect of the detected metabolites, in vitro experimentation was carried out on kidney cells models: HEK-293 and MDCK. Standards of β-carotene, indoleacetic acid and caffeic acid, hydroalcoholic and carotenoid-enriched extracts from samples of pasta were tested in presence of antioxidant agent to determine viability variations. β-carotene and indoleacetic acid standards exerted a protective effect on HEK-293 cells while no effect was detected on MDCK. The concentrations tested are likely in the range of those reached in body after the consumption of a standard pasta meal. Carotenoid-enriched extracts and hydroalcoholic extracts showed different effects, observing rescues for rye pasta hydroalcoholic extract and buckwheat pasta carotenoid-enriched extract, while egg pasta showed milder dose depending effects assuming pro-oxidant behavior at high concentrations. The preliminary results suggest behaviors to be traced back to the whole phytocomplexes respect to single molecules and need further investigations.

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