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MacNicol JL, Pearson W. Gastrin and Nitric Oxide Production in Cultured Gastric Antral Mucosa Are Altered in Response to a Gastric Digest of a Dietary Supplement. Front Vet Sci 2021; 8:684203. [PMID: 34671658 PMCID: PMC8520902 DOI: 10.3389/fvets.2021.684203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Accepted: 08/31/2021] [Indexed: 12/04/2022] Open
Abstract
In vitro organ culture can provide insight into isolated mucosal responses to particular environmental stimuli. The objective of the present study was to investigate the impact of a prolonged culturing time as well as the addition of acidic gastric fluid into the in vitro environment of cultured gastric antral tissue to evaluate how altering the commonly used neutral environment impacted tissue. Furthermore, we aimed to investigate the impact of G's Formula, a dietary supplement for horses, on the secretion of gastrin, interleukin1-beta (IL-1β), and nitric oxide (NO). These biomarkers are of interest due to their effects on gastric motility and mucosal activity. Gastric mucosal tissue explants from porcine stomachs were cultured in the presence of a simulated gastric fluid (BL, n = 14), simulated gastric fluid containing the dietary supplement G's Formula (DF, n = 12), or an equal volume of phosphate buffered saline (CO, n = 14). At 48 and 60 h, 10−5 M carbachol was used to stimulate gastrin secretion. Cell viability was assessed at 72 h using calcein and ethidium-homodimer 1 staining. Media was analyzed for gastrin, IL-1β, and NO at 48, 60, and 72 h. There were no effects of treatment or carbachol stimulation on explant cell viability. Carbachol resulted in a significant increase in gastrin concentration in CO and DF treatments, but not in BL. NO was higher in CO than in BL, and NO increased in the CO and DF treatments but not in BL. In conclusion, the addition of carbachol and gastric digests to culture media did not impact cell viability. The use of an acidic gastric digest (BL) reduced the effect of cholinergic stimulation with carbachol at a concentration of 10−5 M and reduced NO secretion. The addition of the dietary supplement to the gastric digest (DF) appeared to mediate these effects within this model. Further research is required to evaluate the specific effects of this dietary supplement on direct markers of mucosal activity and the functional relevance of these results in vivo.
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Affiliation(s)
- Jennifer L MacNicol
- Department of Animal Biosciences, Ontario Agricultural College, University of Guelph, Guelph, ON, Canada
| | - Wendy Pearson
- Department of Animal Biosciences, Ontario Agricultural College, University of Guelph, Guelph, ON, Canada
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Bleisinger N, Dittrich R, Strahl O, Brauweiler R, Hoffmann I, Beckmann MW, Volk T. Me2SO perfusion time for whole-organ cryopreservation can be shortened: Results of micro-computed tomography monitoring during Me2SO perfusion of rat hearts. PLoS One 2020; 15:e0238519. [PMID: 32877442 PMCID: PMC7467318 DOI: 10.1371/journal.pone.0238519] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Accepted: 08/18/2020] [Indexed: 11/18/2022] Open
Abstract
Cryopreservation of whole organs and specific tissues is an important and continually expanding field of medicine. The protocols currently used for organ preservation do not ensure survivability and functionality; the protocols for ovarian tissue lead to acceptable outcomes, but these are still capable of further improvement. In general, cryopreservation protocols need to be optimized. One important approach to improving cryopreservation protocols in general involves reducing exposure to cytotoxic cryoprotective agents prior to freezing. This study, therefore, evaluated the real-time tissue penetration of dimethyl sulfoxide, a cryoprotective agent that is widely used in cryopreservation. Dimethyl sulfoxide penetration in rat hearts perfused with a 15% (v/v) dimethyl sulfoxide solution was examined in real-time using dynamic contrast-enhanced micro-computed tomography imaging. Viability of cardiomyocytes was not significantly affected by the dimethyl sulfoxide perfusion procedure. Two different perfusion rates were evaluated and compared with perfusion using a common iodine-based contrast agent (iomeprol). The dynamic contrast-enhanced micro-computed tomography imaging data showed that dimethyl sulfoxide flushes both the extracellular and intracellular spaces in rat heart tissue to 95% equilibration after ≈ 35 s via perfusion. Subsequent wash-out via perfusion is completed to 95% within ≈ 49 s. The equilibration duration routinely used in dimethyl sulfoxide–based protocols for cryopreservation should therefore be questioned. Shorter incubation duration would perhaps be sufficient, as well as being beneficial in relation to cell survivability. It would be helpful to have techniques for non-invasive real-time monitoring of the penetration of cryoprotective agents and such techniques should be used to revise cryopreservation protocols. Switching to perfusion-based equilibration procedures might be beneficial, if feasible.
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Affiliation(s)
- Nathalie Bleisinger
- Department of Obstetrics and Gynaecology, Erlangen University Hospital, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen, Germany
| | - Ralf Dittrich
- Department of Obstetrics and Gynaecology, Erlangen University Hospital, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen, Germany
- * E-mail:
| | - Olga Strahl
- Department of Obstetrics and Gynaecology, Erlangen University Hospital, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen, Germany
| | - Robert Brauweiler
- Institute of Medical Physics, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen, Germany
| | - Inge Hoffmann
- Department of Obstetrics and Gynaecology, Erlangen University Hospital, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen, Germany
| | - Matthias W. Beckmann
- Department of Obstetrics and Gynaecology, Erlangen University Hospital, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen, Germany
| | - Tilmann Volk
- Institute of Cellular and Molecular Physiology, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen, Germany
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Joshi P, Rabin Y. Thermal analysis of marginal conditions to facilitate cryopreservation by vitrification using a semi-empirical approach. Cryobiology 2019; 91:128-136. [PMID: 31526802 PMCID: PMC7383435 DOI: 10.1016/j.cryobiol.2019.09.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Revised: 09/12/2019] [Accepted: 09/12/2019] [Indexed: 11/28/2022]
Abstract
This study aims at the thermal analysis of marginal conditions leading to cryopreservation by vitrification, which appears to be the only alternative for indefinite preservation of large-size tissues and organs. The term "marginal conditions" here refers to cooling rates in close range with the so-called critical cooling rate, above which crystallization is avoided. The analysis of thermal effects associated with partial crystallization during vitrification is associated with the coupled phenomena of heat transfer and kinetics of crystallization. This study takes a practical, semi-empirical approach, where heat transfer is analyzed based on its underlying theoretical principles, while the thermal effects associated with partial crystallization are taken into account by means of empirical correlations. This study presents a computation framework to solve the coupled problem, while presenting a proof-of-concept for DP6 as a representative cryoprotective agent. The thermal effects associated with crystallization at various relevant cooling rates are measured in this study by means of differential scanning calorimetry. Results of this study demonstrate that, due to the thermal effects associated with partial crystallization, the cooling rate at the center of a large organ may lag behind the cooling rate in its surroundings under some scenarios, but may also exceed the surroundings cooling rate in other scenarios, leading to counter-intuitive effects associated with partial crystallization.
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Affiliation(s)
- Purva Joshi
- Department of Mechanical Engineering, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA, 15213, USA
| | - Yoed Rabin
- Department of Mechanical Engineering, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA, 15213, USA.
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Cryopreservation by vitrification: a promising approach for transplant organ banking. Curr Opin Organ Transplant 2019; 23:353-360. [PMID: 29702495 DOI: 10.1097/mot.0000000000000534] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
PURPOSE OF REVIEW The objective of this review is to describe the physical and biological barriers to organ cryopreservation, historic approaches for conventional cryopreservation and evolving techniques for ice-free cryopreservation by vitrification. RECENT FINDINGS Vitrification is a process whereby a biologic substance is cooled to cryogenic temperatures without the destructive phase transition of liquid to solid ice. Recent advances in cryoprotective solutions, organ perfusion techniques and novel heating technologies have demonstrated the potential for vitrification and rewarming organs on a scale applicable for human transplantation. SUMMARY Successful strategies for organ cryopreservation could enable organ banking, which would recast the entire process in which organs are recovered, allocated, stored and prepared for transplant.
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Ehrlich LE, Fahy GM, Wowk BG, Malen JA, Rabin Y. Thermal Analyses of a Human Kidney and a Rabbit Kidney During Cryopreservation by Vitrification. J Biomech Eng 2018; 140:2646923. [PMID: 28753690 PMCID: PMC5676646 DOI: 10.1115/1.4037406] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2017] [Revised: 07/07/2017] [Indexed: 12/12/2022]
Abstract
This study focuses on thermal analysis of the problem of scaling up from the vitrification of rabbit kidneys to the vitrification of human kidneys, where vitrification is the preservation of biological material in the glassy state. The basis for this study is a successful cryopreservation protocol for a rabbit kidney model, based on using a proprietary vitrification solution known as M22. Using the finite element analysis (FEA) commercial code ANSYS, heat transfer simulations suggest that indeed the rabbit kidney unquestionably cools rapidly enough to be vitrified based on known intrarenal concentrations of M22. Scaling up 21-fold, computer simulations suggest less favorable conditions for human kidney vitrification. In this case, cooling rates below -100 °C are sometimes slower than 1 °C/min, a rate that provides a clear-cut margin of safety at all temperatures based on the stability of rabbit kidneys in past studies. Nevertheless, it is concluded in this study that vitrifying human kidneys is possible without significant ice damage, assuming that human kidneys can be perfused with M22 as effectively as rabbit kidneys. The thermal analysis suggests that cooling rates can be further increased by a careful design of the cryogenic protocol and by tailoring the container to the shape of the kidney, in contrast to the present cylindrical container. This study demonstrates the critical need for the thermal analysis of experimental cryopreservation and highlights the unmet need for measuring the thermophysical properties of cryoprotective solutions under conditions relevant to realistic thermal histories.
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Affiliation(s)
- Lili E. Ehrlich
- Department of Mechanical Engineering,
Carnegie Mellon University,
Pittsburgh, PA 15213
| | | | | | - Jonathan A. Malen
- Department of Mechanical Engineering,
Carnegie Mellon University,
Pittsburgh, PA 15213
| | - Yoed Rabin
- Department of Mechanical Engineering,
Carnegie Mellon University,
Pittsburgh, PA 15213
e-mail:
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Schölch D, Schölch S, Strahl O, Hoffmann I, Beckmann MW, Dittrich R. Porcine uterus cryopreservation: an analysis of contractile function using different uterotonics. Cryobiology 2012; 65:88-92. [PMID: 22676999 DOI: 10.1016/j.cryobiol.2012.05.009] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2011] [Revised: 05/27/2012] [Accepted: 05/28/2012] [Indexed: 10/28/2022]
Abstract
Cryopreservation of whole organs has become increasingly successful in recent years, and establishing reliable methods for confirming the success of specific cryopreservation procedures has therefore become extremely important. On the assumption that methods such as histological evaluation do not provide definitive evidence of long-term cryopreservation and that clear signs of conserved function in an organ are good evidence of its viability, contractile function was analysed in porcine uteri (n=60), either after long-term (group A) or short-term (group B) cryopreservation and post-thaw treatment with three different uterotonics. A slow freezing protocol was used to preserve the organs. Fifteen fresh uteri were analysed similarly for contractile function, which was evaluated by measuring intrauterine pressure after administration of oxytocin, prostaglandin E(1) (PGE(1)), and carbachol. After cryopreservation, all but three uteri (95%) showed rhythmic contractions similar to those in fresh uteri except for differences in the heights of contraction peaks, with lower contractions in PGE(1) subgroup B (P<0.05). With the exception of three nonresponsive uteri in group A, there were no differences in contractility between uteri after long-term cryopreservation and fresh uteri. The results of this study thus contribute to the debate on whether slow freezing or vitrification techniques are best for whole-organ cryopreservation. In summary, (1) preservation of muscular function in porcine uteri is feasible with a slow freezing protocol; (2) measurement of contractile function following administration of uterotonics is a useful method of confirming functionality; and (3) long-term cryopreservation does not significantly impair post-thaw contractibility in comparison with fresh uteri.
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Affiliation(s)
- Daniel Schölch
- Department of Obstetrics and Gynecology, Erlangen University Hospital, University of Erlangen-Nuremberg, Erlangen, Germany
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Dittrich R, Henning J, Maltaris T, Hoffmann I, Oppelt PG, Cupisti S, Beckmann MW, Mueller A, Kiesewetter F. Extracorporeal perfusion of the swine uterus: effect of human seminal plasma. Andrologia 2011; 44 Suppl 1:543-9. [DOI: 10.1111/j.1439-0272.2011.01223.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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Dittrich R, Sinduwinatha C, Maltaris T, Mueller A, Hoffmann I, Beckmann MW, Oppelt PG. The intrauterine to intra-arterial pressure ratio: a new parameter for the study of uterine contractility physiology. Reprod Biomed Online 2009; 20:430-6. [PMID: 20093083 DOI: 10.1016/j.rbmo.2009.11.023] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2009] [Revised: 06/23/2009] [Accepted: 11/17/2009] [Indexed: 10/20/2022]
Abstract
The objective of the study was to examine the uterine contractions and the arterial perfusion pressure changes after application of oxytocin, endothelin 1, prostaglandins PGE(1), PGE(2) and PGF(2alpha), in order to identify the substance with the greatest intrauterine pressure (IUP)/intra-arterial pressure (IAP) ratio, which means the substance most suitable for inducing uterine contractility without raising the systemic vascular pressure. Increasing doses of oxytocin, endothelin 1, PGE(1), PGE(2) and PGF(2alpha) were applied as bolus injection through the uterine artery of perfused swine uteri and the intrauterine and intra-arterial pressure rises were recorded. All substances showed a significant cervicofundic pressure gradient and, with the exception of PGF(2alpha), the uterine peristalsis moved towards the cervix uteri. The perfusion pressure after application of oxytocin, PGE(1), PGE(2) and PGF(2alpha) reached a maximum value and started to decrease, whereas endothelin 1 caused a continuous increase in the perfusion pressure. Endothelin 1 showed the lowest IUP/IAP ratio and oxytocin the greatest. In conclusion, the IUP/IAP ratio provides a promising new parameter for the study of uterine contractility physiology. Besides oxytocin, PGE(2) and PGF(2alpha) emerged as the best candidate substances to improve uterine contractility without raising the intra-arterial pressure.
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Affiliation(s)
- R Dittrich
- University Hospital Erlangen, Department of Obstetrics and Gynecology, University of Erlangen-Nuremberg, Universitaetsstrasse 21-23, D-91054 Erlangen, Germany.
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Dittrich R, Beckmann MW, Mueller A, Binder H, Hoffmann I, Maltaris T. Uterus cryopreservation: maintenance of uterine contractility by the use of different cryoprotocols. Reprod Domest Anim 2008; 45:86-91. [PMID: 18992117 DOI: 10.1111/j.1439-0531.2008.01258.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Cryopreservation of cells and even tissue is feasible. New exciting findings arise in the promising field of cryobiology, e.g. the cryopreservation of whole ovaries. Uterus cryopreservation would be advantageous not only for experimental biology, but also for transplantation surgery. The objective of this study was to evaluate various cryopreservation protocols as well as various storage temperatures in cryopreservation of whole swine uteri. The used freezing protocol was slow (0.2 degrees C/min) after arterial perfusion with 1%, 5% or 10% dimethyl sulfoxide (DMSO) solution for 10 min and equilibration in this solution for 30 min. Viability of the organs was tested by histological examination, biochemical parameters and by the capability of rhythmical contractions in a perfusion system. Eighty swine uteri were cryopreserved. All uteri that were frozen with 10% and 5% DMSO were viable after thawing for at least 1 h, whereas only 40% survived with the use of 1% DMSO and 0% with the use of 0.5% DMSO, respectively. There was no difference regarding the survival rates after various cryostorage periods for up to 16 weeks or after cryostorage for 2 weeks in -70 degrees C or -130 degrees C. The cryopreservation of a whole organ such as the swine uterus is a valuable method for the study of cryoprotective agents and freezing protocols. This study demonstrates clearly that the perfusion of the organ with cryoprotectants is the only factor which allows the uterus to contract.
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Affiliation(s)
- R Dittrich
- Department of Obstetrics and Gynecology, Erlangen University Hospital, University of Erlangen-Nuremberg, Erlangen, Germany.
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Dittrich R, Mueller A, Binder H, Oppelt PG, Renner SP, Goecke T, Hoffmann I, Beckmann WM. First retransplantation of cryopreserved ovarian tissue following cancer therapy in Germany. DEUTSCHES ARZTEBLATT INTERNATIONAL 2008; 105:274-8. [PMID: 19629232 DOI: 10.3238/arztebl.2008.0274] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2007] [Accepted: 01/10/2008] [Indexed: 11/27/2022]
Abstract
INTRODUCTION New anticancer treatments have increased survival rates for cancer patients but often at the cost of sterility. One way of preserving fertility in these patients is the use of cryopreservation of ovarian tissue with subsequent retransplantation following a period of recurrence-free survival. We report the follow-up of the first case of retransplantation of ovarian tissue in Germany. METHODS Immediately following the diagnosis of anal cancer, ovarian tissue was removed laparoscopically, and cryopreserved. The patient was then treated with combined radiochemotherapy, which resulted in iatrogenic premature ovarian failure, and was associated with inhibin B serum levels lower than 10 ng/L. After the 2.5 year period of cancer remission, the cryopreserved ovarian tissue was retransplanted orthotopically. RESULTS Five months later estradiol serum levels had risen from lower than 20 pg/mL to 436 pg/mL. Three ovarian follicles were detected ultrasonographically in the pelvic side wall. Finally the patient reported her first menstruation after the intervention. The endocrine activity of the transplanted cryopreserved tissue has demonstrated viability, and the ability to develop. DISCUSSION Cycle monitoring and timed intercourse should now help to achieve conception. These first results from Germany for retransplantation of cryopreserved ovarian tissue clearly show its potential for preserving fertility.
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Affiliation(s)
- Ralf Dittrich
- Frauenklinik des Universitätsklinikums Erlangen, Universitätsstrasse 21-23, Erlangen, Germany.
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Isachenko V, Isachenko E, Reinsberg J, Montag M, Braun F, van der Ven H. Cryopreservation of human ovarian tissue: effect of spontaneous and initiated ice formation. Reprod Biomed Online 2008; 16:336-45. [DOI: 10.1016/s1472-6483(10)60593-7] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Fahy G, Wowk B. Response to: “Cryopreservation of Complex Systems: Slow Freezing Has Not Had Its Day Yet ”. Rejuvenation Res 2007. [DOI: 10.1089/rej.2006.9421] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- G.M. Fahy
- Intervene Biomedica, Box 478, Norco, CA 92860, E-mail:
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Dittrich R, Mueller A, Hoffmann I, Beckmann MW, Maltaris T. Cryopreservation of Complex Systems: Slow Freezing Has Not Had Its Day Yet. Rejuvenation Res 2007; 10:101-2; author reply 103-5. [PMID: 17378756 DOI: 10.1089/rej.2006.9095] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
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Dittrich R, Beckmann MW, Maake C, Oppelt PG, Mueller A, Mueller S, Hoffmann I, Naumann G, Koelbl H, Maltaris T. The extracorporeal perfusion of the female pig detrusor as an experimental model for the study of bladder contractility. Neurourol Urodyn 2007; 26:1024-9. [PMID: 17638308 DOI: 10.1002/nau.20443] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
AIMS The objective of the study was to establish an experimental model for the extracorporeal perfusion of the pig detrusor. In order to validate this model we examined some biochemical parameters and determined the effect of carbachol on the contractility of perfused female pig bladders. METHODS Twenty-six pig bladders were perfused with Krebs-Ringer bicarbonate-glucose buffer for a period up to 5 hr with the aim to preserve a viable organ, which would be responsive to contraction-inducing agents. The intravesical pressure of the bladder as well as the intraarterial pressure of the vesical arteries were recorded before and after administration of carbachol. RESULTS The perfusate pH, lactate, partial carbon dioxide tension, and the ATP content in the perfused tissue, all indicators of tissue ischemia or cell necrosis, showed a good preservation of the organ for up to 5 hr. Carbachol was able to induce contractions of the prefilled bladder with a complete draining of the bladder throughout the whole perfusion period. CONCLUSIONS We could demonstrate that this perfusion system was able to preserve the pig bladder in a functional condition, appropriate for the study of physiological questions.
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Affiliation(s)
- Ralf Dittrich
- Department of Obstetrics and Gynecology, Erlangen University Hospital, Erlangen, Germany.
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