Survey of Apoptosis After Hypothermic Storage of a Pancreatic β-Cell Line

Abstract

Insulin-dependent diabetes mellitus is one of the leading causes of death world wide. Donor-derived pancreas and islet of Langerhans transplantation are potential cures, however, postmortem ischemia impacts islet quality. The murine bt3 cell line was used as a model to study apoptosis after hypothermic storage by comparing UnisolÔ with Belzer's machine perfusion solution (BMPS) and the University of Wisconsin (UW) solution. The objective was to determine which of these solutions provided the best support for bt3 cells and which solution demonstrated the least amount of apoptotic activity. Several apoptosis markers were measured that included the translocation of phosphatidylserine, caspase activity, and the formation of DNA laddering. In addition, metabolic activity and membrane integrity were also measured. The results demonstrated that the three solutions behaved similarly during overnight cold storage at 4°C. However, Unisol was consistently better than UW solution and BMPS, demonstrating better cell viability and recovery, and lower levels of apoptotic activity when all three parameters were measured. These results demonstrated that apoptosis plays an important role in the survival of cells and tissues during cold storage. Development of solutions to help prevent or decrease the levels of apoptosis after cold storage will likely improve overall cell and tissue recovery and survival in a clinical setting.

Bilirubin Improves the Quality and Function of Hypothermic Preserved Islets by Its Antioxidative and Anti-inflammatory Effect

“…3,4 Many efforts have been made to extend the islet ex vivo lifetime by exploiting the storage time, temperature, culture solution components, and methods. 5,6 Many studies compared the effect of temperature on the islet preservation, and there is still a lack of consensus. 7 Hypothermic preservation in a short time (<7 days) is commonly applied in research and clinical islet transplantation.…”

“…7 Hypothermic preservation in a short time (<7 days) is commonly applied in research and clinical islet transplantation. 6 Many additives in storage solution have been reported to improve the recovery and functions of preserved islets, and among them, antioxidative and anti-inflammatory ingredients showed superior advantages. [8][9][10] As mentioned, hypoxiainduced oxidative stress is one of the primary causes of the apoptosis and dysfunction of preserved islets.…”

Gluconate-Lactobionate-Dextran Perfusion Solutions Attenuate Ischemic Injury and Improve Function in a Murine Cardiac Transplant Model

“…Preservation solutions, regardless of whether they are designed to be intracellularor extracellular-type solutions, contain various components that aim to ameliorate ischemia/reperfusion injury, including (1) buffer systems to prevent acidosis, (2) oncotic active agents that prevent intracellular water influx and thus cell edema and swelling, (3) high-energy compounds that provide substrates for regeneration during cold storage and upon reperfusion, and (4) antioxidants to mitigate oxidative stress [18][19][20]. Unisol contains HEPES, a zwitterion buffer effective for pH control in cold temperatures; large molecules lactobionic acid, gluconate, and dextran with oncotic activity; and glucose, sucrose, and adenosine as energy substrates (Table 1).…”

“…Unisol has thus far been investigated for preservation of pancreatic beta-cells and in the setting of swine clinical suspended animation [18,20]. For beta-cells, Campbell et al demonstrated superior cell viability, and lower levels of apoptotic activity in Unisol-stored cells compared to ones stored in UW and Belzer's machine perfusion solution [18,19].…”