Background: Adult porcine islets (APIs) constitute a promising alternative to human islets in treating type 1 diabetes. The intrahepatic site has been used in preclinical primate studies of API xenografts; however, an estimated two-thirds of donor islets are destroyed after intraportal infusion due to a number of factors, including the instant blood-mediated inflammatory reaction (IBMIR), immunosuppressant toxicity, and poor reestablishment of extracellular matrix connections. Intraperitoneal (ip) transplantation of non-vascularized encapsulated islets offers several advantages over intrahepatic transplantation of free islets, including avoidance of IBMIR, immunoprotection, accommodation of a larger graft volume, and reduced risk of hemorrhage. However, there exists evidence that the peritoneal site is hypoxic, which likely impedes islet function.
Methods: We tested the effect of hypoxia (2%-5% oxygen or pO : 15.2-38.0 mm Hg) on free and encapsulated APIs over a period of 6 days in culture. Free and encapsulated APIs under normoxia served as controls. Islet viability was evaluated with a viability/cytotoxicity assay using calcein AM and ethidium bromide on days 1, 3, and 6 of culture. Alamar blue assay was used to measure the metabolic activity on days 1 and 6. Insulin in spent medium was assayed by ELISA on days 1 and 6.
Results: Viability staining indicated that free islet clusters lost their integrity and underwent severe necrosis under hypoxia; encapsulated islets remained intact, even when they began to undergo necrosis. Under hypoxia, the metabolic activity and insulin secretion (normalized to metabolic activity) of both free and encapsulated islets decreased relative to islets cultured under normoxic conditions.
Conclusions: Hypoxia (2%-5% oxygen or pO : 15.2-38.0 mm Hg) affects the viability, metabolic activity, and insulin secretion of both free and encapsulated APIs over a six-day culture period. Encapsulation augments islet integrity under hypoxia, but it does not prevent loss of viability, metabolic activity, or insulin secretion.
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http://dx.doi.org/10.1111/xen.12275 | DOI Listing |
Appl Biochem Biotechnol
December 2024
Department of Life Science, Sharda School of Basic Sciences and Research, Sharda University, Greater Noida, U.P, 201310, India.
This study aimed to determine the effects of novel N-{3-[(pyridin-4-yl)carbamoyl] phenyl} thiophene-2-carboxamide or PCPTC chemical moiety loaded Poly(lactic-co-glycolic acid)-Poly (Ethylene glycol) or (PLGA-PEGylated) NP as an anti-metastatic Ran GTPase therapeutic agent on MDA-MB231 triple-negative human breast cancer cells. Molecular docking and MD simulation was done to determine the binding potential of novel carboxamide PCPTC with Ran GTPase. PLGA and PLGA-PEG based NP encapsulating PCPTC were fabricated using the Modified Double Emulsion Solvent Evaporation Technique and characterized for size, zeta potential, polydispersity and morphology.
View Article and Find Full Text PDFADMET DMPK
October 2024
PSIT-Pranveer Singh Institute of Technology (Pharmacy), Kanpur-209305, U.P., India.
Background And Purpose: The study explores basil seed mucilage as a bioadhesive carrier for naproxen sodium, demonstrating its ability to enhance solubility when administered rectally. The mucilage, derived from seeds, showed bioadhesive properties and thermal stability, as confirmed by FTIR spectroscopy and X-ray diffraction analysis.
Experimental Approach: Microspheres were prepared using a double emulsion solvent evaporation technique, varying polymer ratios to optimize drug delivery.
Int J Biol Macromol
December 2024
School of Food and Biological Engineering, Chengdu University, No. 2025 Chengluo Avenue, Chengdu 610106, China. Electronic address:
Owing to the limited availability of biocompatible, edible and natural emulsifiers, the development of Pickering emulsions applicable to the food industry still confronts challenges. Moreover, Honokiol (HNK), due to its poor stability and susceptibility to oxidation, most of the existing delivery systems are centered on injection administration routes and relatively complex in preparation, posing significant challenges for industrialization. In this research, a Pickering emulsion system stabilized by gliadin and konjac glucomannan composite particles (GKPs) was constructed using the pH cycling method and was employed for the delivery of HNK.
View Article and Find Full Text PDFInt J Biol Macromol
December 2024
AI Agri-Tech Research Center, Chonnam National University, Gwangju 61186, Republic of Korea; Department of Convergence Biosystems Engineering, Chonnam National University, Gwangju 61186, Republic of Korea; BK21 Interdisciplinary Program in IT-Bio Convergence System, Chonnam National University, Gwangju 61186, Republic of Korea. Electronic address:
Hydrogels in agriculture offer controlled release, however, face issues with rapid disintegration, swift release, and inability to protect active ingredients. To overcome this, the study presents a hydrogel delivery system that uses dopamine-functionalized nanoporous diatom (DE-PDA) microparticles entrapped in alginate and chitosan matrices to deliver plant growth hormone, gibberellic acid (GA) that suffers from instability, limiting its field application. Developed GA@hydrogel beads exhibited an encapsulation efficiency of 85.
View Article and Find Full Text PDFFood Chem
December 2024
College of Food Science and Technology, Huazhong Agricultural University, Wuhan, Hubei 430070, PR China; Key Laboratory of Environment Correlative Dietology (Huazhong Agricultural University), Ministry of Education, Wuhan, Hubei 430070, PR China. Electronic address:
Improving sea buckthorn flavonoids (SF) stability and bioacccessibility is of more practical significance for evaluating the total bioacccessibility of such foods. Therefore, we prepared nanoparticles using zein and gum Arabic (GA) by anti-solvent precipitation to encapsulate SF. Nanoparticles were characterized and assessed for their effect on the stability, release, bioaccessibility, absorption, and antioxidant properties of SF in the in vitro digestion and cell line.
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