Photosynthetic oxygen generator for bioartificial pancreas.
Immunoisolation of pancreatic islets interrupts their vascular connections and results in severe cell hypoxia and dysfunction. This process is believed to be the major obstacle to a successful cure of diabetes by implantation of bioartificial pancreas. Here we describe a new technology for microalga-based, photosynthetic oxygen supply to encapsulated islets, in which a thermophylic strain of the unicellular alga Chlorella was used as a natural photosynthetic oxygen generator. Following determinations of the optimal number of alga cells required for compensation of islet respiration, an appropriate number of islets and algae were co-encapsulated in alginate and perifused with oxygen-free medium at increasing glucose concentrations. No insulin response to glucose was obtained in islets alone, or upon inactivation of photosynthesis by darkness. However, under illumination, photosynthetic- dependent oxygen generation induced higher glucose-stimulated insulin response when compared to normoxic perifusion. Such photosynthetic oxygen generation may have a potential application in development of various bioartificial tissues, in particular the endocrine pancreas.
Diabetes and Obesity Research Laboratory, Felsenstein Medical Research Center, Sackler Faculty of Medicine, Tel-Aviv University, Beilinson Campus, Petah Tikva, Israel.
Konstantin
K
Bloch
Eli
E
Papismedov
Karina
K
Yavriyants
Marina
M
Vorobeychik
Sven
S
Beer
Pnina
P
Vardi
D000464:Alginates / Q000378:metabolism; D000818:Animals; D002478:Cells, Cultured; D002708:Chlorella / Q000166:cytology / Q000254:growth & development / Q000378:metabolism / Q000528:radiation effects; D017364:Collagenases / Q000494:pharmacology; D005856:Germ-Free Life; D020723:Glucuronic Acid / Q000378:metabolism; D006603:Hexuronic Acids / Q000378:metabolism; D007328:Insulin / Q000378:metabolism; D000078790:Insulin Secretion; D007340:Insulinoma / Q000378:metabolism; D007515:Islets of Langerhans / Q000166:cytology / Q000187:drug effects / Q000502:physiology*; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D010100:Oxygen / Q000378:metabolism*; D010101:Oxygen Consumption; D019397:Pancreas, Artificial; D010190:Pancreatic Neoplasms / Q000378:metabolism; D010477:Perfusion; D017785:Photons; D010788:Photosynthesis
D000464:Alginates; D006603:Hexuronic Acids; D007328:Insulin; D020723:Glucuronic Acid; D017364:Collagenases; D010100:Oxygen