Establishment of a model for equine small intestinal disease: effects of extracorporeal blood perfusion of equine ileum on metabolic variables and histological morphology - an experimental ex vivo study

Normothermic Machine Perfusion Systems: Where Do We Go From Here?

Normothermic machine perfusion (NMP) aims to preserve organs ex vivo by simulating physiological conditions such as body temperature. Recent advancements in NMP system design have prompted the development of clinically effective devices for liver, heart, lung, and kidney transplantation that preserve organs for several hours/up to 1 d. In preclinical studies, adjustments to circuit structure, perfusate composition, and automatic supervision have extended perfusion times up to 1 wk of preservation. Emerging NMP platforms for ex vivo preservation of the pancreas, intestine, uterus, ovary, and vascularized composite allografts represent exciting prospects. Thus, NMP may become a valuable tool in transplantation and provide significant advantages to biomedical research. This review recaps recent NMP research, including discussions of devices in clinical trials, innovative preclinical systems for extended preservation, and platforms developed for other organs. We will also discuss NMP strategies using a global approach while focusing on technical specifications and preservation times.

Progress in preservation of intestinal grafts by oxygenated hypothermic machine perfusion

Intestine transplantation (IT) is a critical treatment strategy for irreversible intestinal failure. Among all abdominal solid organ transplants, the intestine was the most vulnerable to ischemia and reperfusion injury (IRI). The static cold storage (SCS) technique is currently the most commonly used graft preservation method, but its hypoxia condition causes metabolic disorders, resulting in the occurrence of IRI, limiting its application in marginal organs. It is especially important to improve preservation techniques in order to minimize damage to marginal donor organs, which draws more attention to machine perfusion (MP). There has been much debate about whether it is necessary to increase oxygen in these conditions to support low levels of metabolism since the use of machine perfusion to preserve organs. There is evidence that oxygenation helps to restore intracellular ATP levels in the intestine after thermal or cold ischemia damage. The goal of this review is to provide an overview of the role of oxygen in maintaining environmental stability in the gut under hypoxic conditions, as well as to investigate the possibilities and mechanisms of oxygen delivery during preservation in intestine transplantation studies and clinical models.

In vitro effects of essential oils of Tanacetum balsamita and carvone on the contractility of bovine ileum smooth muscles

Tanacetum balsamita (Asteraceae) is a medicinal plant previously used in human medicine to solve gastrointestinal problems such as abdominal pain. Anti-inflammatory, analgesic, immune-modulatory, and antioxidant effects of T. balsamita have been proven in previous studies. The present study investigated the effects of T. balsamita essential oil (TBEO) on ruminant smooth muscle contractions. The experiment was performed on the circular smooth muscle of ileum samples taken from slaughtered bulls in the organ bath. Nine cumulative concentrations of TBEO from 0.10 to 1000 µg mL^-1 were added to tissue samples. The solution used was Tyrode's solution aerated with a mixture of 95.00% oxygen and 5.00% carbon dioxide, and the temperature was set at 37.00 ˚C. The effect of TBEO on baseline contractions and three induced contractions with potassium chloride, barium chloride, and carbachol was investigated. In GC-MS analysis of TBEO, carvone was identified as a major ingredient. The effects of eight concentrations of 0.001 to 10.00 µM of carvone on all contractions were investigated under similar conditions. The effects of TBEO, carvone, and verapamil (standard calcium channel blocker) on calcium channels were assessed. The results revealed that TBEO and carvone significantly inhibit spontaneous contractions as well as all spasmogen-induced contractions. The TBEO and carvone exert their myorelaxant properties by inhibiting Ca⁺⁺ channels in smooth muscle. The anti-spasmodic properties of T. balsamita can be employed for the treatment of intestinal spasms or hypermotility.