Hypothermic treatment after computer-controlled compression in minipig: A preliminary report on the effect of epidural vs. direct spinal cord cooling
EXPERIMENTAL AND THERAPEUTIC MEDICINE
Authors: Zavodska, Monika; Galik, Jan; Marsala, Martin; Papcunova, Stefania; Pavel, Jaroslav; Racekova, Eniko; Martoncikova, Marcela; Sulla, Igor; Gajdos, Miroslav; Lukac, Imrich; Kafka, Jozef; Ledecky, Valent; Sulla, Igor, Jr.; Reichel, Peter; Trbolova, Alexandra; Capik, Igor; Bimbova, Katarina; Bacova, Maria; Stropkovska, Andrea; Kisucka, Alexandra; Miklisova, Dana; Lukacova, Nadezda
Abstract
The aim of the present study was to investigate the therapeutic efficacy of local hypothermia (beginning 30 min post-injury persisting for 5 h) on tissue preservation along the rostro-caudal axis of the spinal cord (3 cm cranially and caudally from the lesion site), and the prevention of injury-induced functional loss in a newly developed computer-controlled compression model in minipig (force of impact 18N at L3 level), which mimics severe spinal cord injury (SCI). Minipigs underwent SCI with two post-injury modifications (durotomy vs. intact dura mater) followed by hypothermia through a perfusion chamber with cold (epidural t approximate to 15 degrees C) saline, DMEM/F12 or enriched DMEM/F12 (SCI/durotomy group) and with room temperature (t approximate to 24 degrees C) saline (SCI-only group). Minipigs treated with post-SCI durotomy demonstrated slower development of spontaneous neurological improvement at the early postinjury time points, although the outcome at 9 weeks of survival did not differ significantly between the two SCI groups. Hypothermia with saline (t approximate to 15 degrees C) applied after SCI-durotomy improved white matter integrity in the dorsal and lateral columns in almost all rostro-caudal segments, whereas treatment with medium/enriched medium affected white matter integrity only in the rostral segments. Furthermore, regeneration of neurofilaments in the spinal cord after SCI-durotomy and hypothermic treatments indicated an important role of local saline hypothermia in the functional outcome. Although saline hypothermia (24 degrees C) in the SCI-only group exhibited a profound histological outcome (regarding the gray and white matter integrity and the number of motoneurons) and neurofilament protection in general, none of the tested treatments resulted in significant improvement of neurological status. The findings suggest that clinically-proven medical treatments for SCI combined with early 5 h-long saline hypothermia treatment without opening the dural sac could be more beneficial for tissue preservation and neurological outcome compared with hypothermia applied after durotomy.
In Vitro Long-Term Expansion and High Osteogenic Potential of Periodontal Ligament Stem Cells: More Than a Mirage
CELL TRANSPLANTATION
Authors: Di Vito, Anna; Giudice, Amerigo; Chiarella, Emanuela; Malara, Natalia; Bennardo, Francesco; Fortunato, Leonzio
Abstract
The periodontal ligament displays a reservoir of mesenchymal stem cells which can account for periodontal regeneration. Despite the numerous studies directed at the definition of optimal culture conditions for long-term expansion of periodontal ligament stem cells (PDLSCs), no consensus has been reached as to what is the ideal protocol. The aim of the present study was to determine the optimal medium formulation for long-term expansion and stemness maintenance of PDLSCs, in order to obtain a sufficient number of cells for therapeutic approaches. For this purpose, the effects of three different culture medium formulations were evaluated on PDLSCs obtained from three periodontal ligament samples of the same patient: minimum essential medium Eagle, alpha modification (alpha-MEM), Dulbecco's modified Eagle's medium (DMEM), both supplemented with 10% fetal bovine serum (FBS), and a new medium formulation, Ham's F12 medium, supplemented with 10% FBS, heparin 0.5 U/ml, epidermal growth factor (EGF) 50 ng/ml, fibroblast growth factor (FGF) 25 ng/ml, and bovine serum albumin (BSA) 1% (enriched Ham's F12 medium; EHFM). PDLSCs grown in EHFM displayed a higher PE-CD73 mean fluorescence intensity compared with cells maintained in alpha-MEM and DMEM, even at later passages. Cells maintained in EHFM displayed an increased population doubling and a reduced population doubling time compared with cells grown in DMEM or alpha-MEM. alpha-MEM, DMEM and EHFM with added dexamethasone, 2-phospho-L-ascorbic acid, and beta-glycerophosphate were all able to promote alkaline phosphatase activity; however, no calcium deposition was detected in PDLSCs cultured in EHFM-differentiation medium. When EHFM-, alpha-MEM- and DMEM-expanded PDLSCs were transferred to a commercial culture medium for the osteogenesis, mineralization became much more evident in confluent monolayers of EHFM-expanded PDLSCs compared with DMEM and alpha-MEM. The results suggest EHFM is the optimal medium formulation for growth and stemness maintenance of primary PDLSCs. Moreover, EHFM confers higher osteogenic potential to PDLSCs compared with cells maintained in the other culture media. Overall, the results of the present work confirmed the advantages of using EHFM for long-term expansion of mesenchymal cells in vitro and the preservation of high osteogenic potential.