Necrostatin-1 Supplementation to Islet Tissue Culture Enhances the In-Vitro Development and Graft Function of Young Porcine Islets

Abstract

Pre-weaned porcine islets (PPIs) represent an unlimited source for islet transplantation but are functionally immature. We previously showed that necrostatin-1 (Nec-1) immediately after islet isolation enhanced the in vitro development of PPIs. Here, we examined the impact of Nec-1 on the in vivo function of PPIs after transplantation in diabetic mice. PPIs were isolated from pancreata of 8–15-day-old, pre-weaned pigs and cultured in media alone, or supplemented with Nec-1 (100 µM) on day 0 or on day 3 of culture (n = 5 for each group). On day 7, islet recovery, viability, oxygen consumption rate, insulin content, cellular composition, insulin secretion capacity, and transplant outcomes were evaluated. While islet viability and oxygen consumption rate remained high throughout 7-day tissue culture, Nec-1 supplementation on day 3 significantly improved islet recovery, insulin content, endocrine composition, GLUT2 expression, differentiation potential, proliferation capacity of endocrine cells, and insulin secretion. Adding Nec-1 on day 3 of tissue culture enhanced the islet recovery, proportion of delta cells, beta-cell differentiation and proliferation, and stimulation index. In vivo, this leads to shorter times to normoglycemia, better glycemic control, and higher circulating insulin. Our findings identify the novel time-dependent effects of Nec-1 supplementation on porcine islet quantity and quality prior to transplantation.

Partial Deletion of Perk Improved High-Fat Diet-Induced Glucose Intolerance in Mice

“…It requires animal models with RIPK1-insufficient islets. Indeed, inhibition of RIPK1 is known to enhance islet function [ 16 ]; therefore, PERK inhibitors might have anti-diabetic effects through attenuation of both PERK and RIPK1.…”

Necrostatin‐1 releasing nanoparticles: In vitro and in vivo efficacy for supporting immunoisolated islet transplantation outcomes

“…These DAMPs activate an inflammation cascade leading to reduced graft survival, and therefore Nec‐1 is proposed to be a promising candidate to improve transplantation outcomes. In addition, by culturing islets in Nec‐1‐containing media before transplantation, diabetic mice became normoglycemic in a shorter period, with faster glucose clearance and higher levels of insulin than islets that were not pre‐exposed to Nec‐1 15 …”

“…In addition, by culturing islets in Nec-1-containing media before transplantation, diabetic mice became normoglycemic in a shorter period, with faster glucose clearance and higher levels of insulin than islets that were not preexposed to Nec-1. 15 However, the therapeutic application of Nec-1 is limited by metabolic instability (short half-life time) and its possible sideeffect as it, for example, also inhibits indoleamine 2,3-dioxygenase, an important component of the response to inflammation. 16,17 To enhance its stability in vitro and in vivo we here studied the incorporation of Nec-1 into poly(D,L-lactide-co-glycolide) (PLGA) nanoparticles (NPs).…”