Pharmacological Preconditioning Improves the Viability and Proangiogenic Paracrine Function of Hydrogel-Encapsulated Mesenchymal Stromal Cells

The efficacy of cell therapy is limited by low retention and survival of transplanted cells in the target tissues. In this work, we hypothesize that pharmacological preconditioning with celastrol, a natural potent antioxidant, could improve the viability and functions of mesenchymal stromal cells (MSC) encapsulated within an injectable scaffold. Bone marrow MSCs from rat (rMSC) and human (hMSC) origin were preconditioned for 1 hour with celastrol 1 μM or vehicle (DMSO 0.1% v / v), then encapsulated within a chitosan-based thermosensitive hydrogel. Cell viability was compared by alamarBlue and live/dead assay. Paracrine function was studied first by quantifying the proangiogenic growth factors released, followed by assessing scratched HUVEC culture wound closure velocity and proliferation of HUVEC when cocultured with encapsulated hMSC. In vivo, the proangiogenic activity was studied by evaluating the neovessel density around the subcutaneously injected hydrogel after one week in rats. Preconditioning strongly enhanced the viability of rMSC and hMSC compared to vehicle-treated cells, with 90% and 75% survival versus 36% and 58% survival, respectively, after 7 days in complete media and 80% versus 64% survival for hMSC after 4 days in low serum media ( p < 0.05 ). Celastrol-treated cells increased quantities of proangiogenic cytokines compared to vehicle-pretreated cells, with a significant 3.0-fold and 1.8-fold increase of VEGFa and SDF-1α, respectively ( p < 0.05 ). The enhanced paracrine function of preconditioned MSC was demonstrated by accelerated growth and wound closure velocity of injured HUVEC monolayer ( p < 0.05 ) in vitro. Moreover, celastrol-treated cells, but not vehicle-treated cells, led to a significant increase of neovessel density in the peri-implant region after one week in vivo compared to the control (blank hydrogel). These results suggest that combining cell pretreatment with celastrol and encapsulation in hydrogel could potentiate MSC therapy for many diseases, benefiting particularly ischemic diseases.

Opioid Preconditioning Modulates Repair Responses to Prevent Renal Ischemia-Reperfusion Injury

Progression to renal damage by ischemia-reperfusion injury (IRI) is the result of the dysregulation of various tissue damage repair mechanisms. Anesthetic preconditioning with opioids has been shown to be beneficial in myocardial IRI models. Our main objective was to analyze the influence of pharmacological preconditioning with opioids in renal function and expression of molecules involved in tissue repair and angiogenesis. Experimental protocol includes male rats with 45 min ischemia occluding the left renal hilum followed by 24 h of reperfusion with or without 60 min preconditioning with morphine/fentanyl. We analyzed serum creatinine and renal KIM-1 expression. We measured circulating and intrarenal VEGF. Immunohistochemistry for HIF-1 and Cathepsin D (CTD) and real-time PCR for angiogenic genes HIF-1α, VEGF, VEGF Receptor 2 (VEGF-R2), CTD, CD31 and IL-6 were performed. These molecules are considered important effectors of tissue repair responses mediated by the development of new blood vessels. We observed a decrease in acute renal injury mediated by pharmacological preconditioning with opioids. Renal function in opioid preconditioning groups was like in the sham control group. Both anesthetics modulated the expression of HIF-1, VEGF, VEGF-R2 and CD31. Preconditioning negatively regulated CTD. Opioid preconditioning decreased injury through modulation of angiogenic molecule expression. These are factors to consider when establishing strategies in pathophysiological and surgical processes.

Pharmacological preconditioning by Nicorandil in prevention of ischaemic myocardial injury during an elective percutaneous coronary intervention

Introduction Elective percutaneous coronary intervention (PCI) is accompanied by intraoperative ischemic myocardial injury (IIMI) up to 30% of the cases despite successfully performed procedure. Pharmacological preconditioning can prevent IIMI; Nicorandil is considered promising for this purpose. Purpose To study the possibility of pharmacological preconditioning by oral Nicorandil to ptevent ischaemic myocardial injury and 4a type myocardial infarction (MI) in patients with a stable form of coronary artery disease (CAD) before PCI. Material and methods 182 patients with CAD and indications for PCI were randomized into two groups: Nicorandil treatment group (additionally to β-blockers and a calcium channel blockers, n=90) and the control group (β-blockers and a calcium channel blockers, n=92). Nicorandil per os was prescribed 2 days before the PCI (30 mg/day); on the day of PCI – 2 hours before intervention (20 mg), 6–12 hours after PCI – 10 mg. The analysis of hs-Troponin I (hs-Tr) and creatine phosphokinase-MB (CK-MB)was carried out before PCI and 24, 72 hours after the procedure. The diagnosis of MI 4a type was established according to fourth universal definition. Double antiplatelet therapy was prescribed to all patients. Results Clinical profile (age, BMI, BP, creatinin clearance, LDL-cholesterol, glucose) of the patient groups were comparable by the basic parameters. The rate of hs-Tr after 24 hours has approached the 99th percentile from the upper limit of normal in 146 patients (80%). The increment of mean level of hs-Tr 24 hours after PCI has not distinguish statistically between the Nicorandil and the control group (364 vs 725 pg/ml, p=0,1). Mean of CK-MB increment in the control group has approached 2,5 ng/ml vs 0,5 ng/ml in the Nicorandil group (p=0.06). Among women (n=61), the increment of hs-Tr in 24 hours after PCI was statistically significantly lower (287 vs 1135 pg/ml, p=0,04) in the Nicorandil group compared to the control group. MI 4a type was detected in 12% of patients in the control group, and it decreased to 3% of patients in the Nicorandil group (p=0,05), it was observed in 21% in women in the control group and in 3% in the Nicorandil group. Conclusion Nicorandil treatment using before PCI decreases the risk of MI 4a in patients with a stable CAD due to the realization of pharmacological preconditioning. Funding Acknowledgement Type of funding source: None