Preclinical Study of DCD and Normothermic Perfusion for Visceral Transplantation.

Considering recent clinical and experimental evidence, expectations for using DCD-derived intestines have increased considerably. However, more knowledge about DCD procedure and long-term results after intestinal transplantation (ITx) is needed. We aimed to describe in detail a DCD procedure for ITx using normothermic regional perfusion (NRP) in a preclinical model. Small bowel was obtained from pigs donors after 1 h of NRP and transplanted to the recipients. Graft Intestinal samples were obtained during the procedure and after transplantation. Ischemia-reperfusion injury (Park-Chiu score), graft rejection and transplanted intestines absorptive function were evaluated. Seven of 8 DCD procedures with NRP and ITx were successful (87.5%), with a good graft reperfusion and an excellent recovery of the recipient. The architecture of grafts was well conserved during NRP. After an initial damage of Park-chiu score of 4, all grafts recovered from ischemia-reperfusion, with no or very subtle alterations 2 days after ITx. Most recipients (71.5%) did not show signs of rejection. Only two cases demonstrated histologic signs of mild rejection 7 days after ITx. Interestingly intestinal grafts showed good absorptive capacity. The study's results support the viability of intestinal grafts from DCD using NRP, contributing more evidence for the use of DCD for ITx.

When less is more: Experimental Bishop-Koop technique for reduction in the use of laboratory animals for intestinal pathophysiological studies.

The use of animals to gain knowledge and understanding of diseases needs to be reduced and refined. In the field of intestinal research, because of the complexity of the gut immune system, living models testing is mandatory. Based on the 3Rs (replacement, reduction and refinement) principles, we aimed to developed and apply the derived-intestinal surgical procedure described by Bishop and Koop (BK) in rats to refine experimental gastrointestinal procedures and reduce the number of animals used for research employing two models of intestinal inflammation: intestinal ischemia-reperfusion injury and chemical-induced colitis. Our results show the feasibility of the application of the BK technique in rodents, with good success after surgical procedure in both small and large intestine (100% survival, clinical recovery and weight regain). A considerable reduction in the use of the number of rats in both intestinal inflammation models (80% in case of intestinal ischemia-reperfusion damage and 66.6% in chemical-induced colitis in our experimental design) was achieved. Compared with conventional experimental models described by various research groups, we report excellent reproducibility of intestinal damage and functionality, survival rate and clinical status of the animals when BK is applied.

Galactomannan as a Potential Modulator of Intestinal Ischemia-Reperfusion Injury.

BACKGROUND: Galactomannan (GAL), a polysaccharide present on the cell wall of several fungi, has shown an ability to modulate inflammatory responses through the dectin-1 receptor in human macrophages. However, studies evaluating the modulatory properties of this polysaccharide in in vivo inflammatory scenarios are scarce. We hypothesized that GAL pretreatment would modulate local and remote damage related to intestinal reperfusion after an ischemic insult. MATERIALS AND METHODS: Adult male Balb/c mice were subjected to intestinal ischemia-reperfusion injury by reversible occlusion of the superior mesenteric artery, consisting of 45 min of ischemia followed by 3 or 24 h of reperfusion. Intragastric GAL (70 mg/kg) was administered 12 h before ischemia, and saline solution was used in the control animals. Jejunum, lung, and blood samples were taken for the analysis of histology, gene expression, plasma cytokine levels, and nitrosative stress. RESULTS: Intestinal and lung histologic alterations were attenuated by GAL pretreatment, showing significant differences compared with nontreated animals. Interleukin 1ß, monocyte chemoattractant protein 1, and IL-6 messenger RNA expression were considerably downregulated in the small intestine of the GAL group. In addition, GAL treatment significantly prevented plasma interleukin 6 and monocyte chemoattractant protein 1 upregulation and diminished nitrate and nitrite levels after 3 h of intestinal reperfusion. CONCLUSIONS: GAL pretreatment constitutes a novel and promising therapy to reduce local and remote damage triggered by intestinal ischemia-reperfusion injury. Further in vivo and in vitro studies to understand GAL's modulatory effects are warranted.

In vitro and in vivo testing of the hypocholesterolemic activity of ergosterol- and ß-glucan-enriched extracts obtained from shiitake mushrooms (Lentinula edodes).

Herein, a supercritical extraction plant (with a 6 L extraction cell) was successfully used to obtain ergosterol-enriched extracts from Lentinula edodes under the following conditions: a temperature of 40 °C, pressure of 225 bar, reaction time of 1-5 h, and the flow rate of 20 L h-1 for recirculated CO2. Moreover, ergosterol (ERG) and the SFE extract (SFE) with highest ergosterol concentration were microemulsified and submitted to in vitro digestion to study their ability to displace cholesterol from dietary mixed micelles (DMMs). ERG was also mixed with a ß-glucan-enriched (33.5%) extract (BGE) obtained from L. edodes to investigate the synergies between them; the results indicated that all these extracts (including BGE without ERG) could reduce the cholesterol levels in the DMMs. However, when ERG and SFE were simultaneously administered to mice with a hypercholesterolemic diet, no significant differences in the serum cholesterol levels were detected as compared to the case of the control. However, when only BGE was administrated to another mice model previously induced with hypercholesterolemia, significant reduction in the cholesterol levels was noticed.

Systemic Glucose Administration Alters Water Diffusion and Microvascular Blood Flow in Mouse Hypothalamic Nuclei - An fMRI Study.

The hypothalamus is the principal regulator of global energy balance, enclosing additionally essential neuronal centers for glucose-sensing and osmoregulation. Disturbances in these tightly regulated neuronal networks are thought to underlie the development of severe pandemic syndromes, including obesity and diabetes. In this work, we investigate in vivo the response of individual hypothalamic nuclei to the i.p. administration of glucose or vehicle solutions, using two groups of adult male C57BL6/J fasted mice and a combination of non-invasive T2 ∗-weighted and diffusion-weighted functional magnetic resonance imaging (fMRI) approaches. MRI parameters were assessed in both groups of animals before, during and in a post-stimulus phase, following the administration of glucose or vehicle solutions. Hypothalamic nuclei depicted different patterns of activation characterized by: (i) generalized glucose-induced increases of neuronal activation and perfusion-markers in the lateral hypothalamus, arcuate and dorsomedial nuclei, (ii) cellular shrinking events and decreases in microvascular blood flow in the dorsomedial, ventromedial and lateral hypothalamus, following the administration of vehicle solutions and (iii) increased neuronal activity markers and decreased microperfusion parameters in the ARC nuclei of vehicle-administered animals. Immunohistochemical studies performed after the post-stimulus phase confirmed the presence of c-Fos immunoreactive neurons in the arcuate nucleus (ARC) from both animal groups, with significantly higher numbers in the glucose-treated animals. Together, our results reveal that fMRI methods are able to detect in vivo diverse patterns of glucose or vehicle-induced effects in the different hypothalamic nuclei.

Main histological parameters to be evaluated in an experimental model of myocardial infarct treated by stem cells on pigs.

Myocardial infarction has been carefully studied in numerous experimental models. Most of these models are based on electrophysiological and functional data, and pay less attention to histological discoveries. During the last decade, treatment using advanced therapies, mainly cell therapy, has prevailed from among all the options to be studied for treating myocardial infarction. In our study we wanted to show the fundamental histological parameters to be evaluated during the development of an infarction on an experimental model as well as treatment with mesenchymal stem cells derived from adipose tissue applied intra-lesionally. The fundamental parameters to study in infarcted tissue at the histological level are the cells involved in the inflammatory process (lymphocytes, macrophages and M2, neutrophils, mast cells and plasma cells), neovascularization processes (capillaries and arterioles) and cardiac cells (cardiomyocytes and Purkinje fibers). In our study, we used intramyocardial injection of mesenchymal stem cells into the myocardial infarction area 1 hour after arterial occlusion and allowed 1 month of evolution before analyzing the modifications on the normal tissue inflammatory infiltrate. Acute inflammation was shortened, leading to chronic inflammation with abundant plasma cells and mast cells and complete disappearance of neutrophils. Another benefit was an increase in the number of vessels formed. Cardiomyocytes and Purkinje fibers were better conserved, both from a structural and metabolic point of view, possibly leading to reduced morbidity in the long term. With this study we present the main histological aspects to be evaluated in future assays, complementing or explaining the electrophysiological and functional findings.

Modified Multivisceral Transplantation with Native Spleen Removal in Rats.

BACKGROUND: Modified multivisceral transplantation (MMVTx) refers to the use of a graft that includes all abdominal organs except the liver. The use of this type of transplant in children and adults expanded over the last years with good results. However, long-term survival in experimental models has not been reported. Our aim is to describe in detail some technical modifications of MMVTx to obtain long-term survival. MATERIALS AND METHODS: Syngeneic (Lewis-Lewis) heterotopic MMVTx was performed in 16 male rats (180-250 g). All procedures were performed under isoflurane anesthesia. The graft consisted of stomach, duodenopancreatic axis, spleen, and small bowel. The vascular pedicle consisted of a conduit of aorta, including the celiac trunk and the superior mesenteric artery (SMA), and the portal vein (PV). The engraftment was performed by end-to-side anastomosis to the infra-renal cava vein and aorta. After reperfusion, the graft was accommodated in the right side of the abdomen, and a terminal ileostomy performed. The native spleen was removed. RESULTS: Donor and recipient time was 39 ± 4.4 minutes and 69 ± 7 minutes, respectively; venous and arterial anastomosis time was 14 ± 1 minutes and 12.3 ± 1 minutes, respectively. Total ischemia time was 77.2 ± 7.9 minutes. Survival was 75% (12/16), six were sacrificed after 2 hours, and six were kept alive for long-term evaluation (more than 1 week). CONCLUSION: Long-term survival is reported after heterotopic MMVTx in rats. The heterotopic MMVTx with native spleen removal would potentially improve the existent models for transplant research. The usefulness of this model warrants further confirmation in allogeneic experiments.

Effect of traditional and modern culinary processing, bioaccessibility, biosafety and bioavailability of eritadenine, a hypocholesterolemic compound from edible mushrooms.

Eritadenine is a hypocholesterolemic compound that is found in several mushroom species such as Lentinula edodes, Marasmius oreades, and Amanita caesarea (1.4, 0.7 and 0.6 mg per g dry weight, respectively). It was synthesized during all developmental stages, being present in higher concentrations in the skin of shiitake fruiting bodies. When subjected to traditional cooking, grilling followed by frying were more adequate methodologies than boiling or microwaving to maintain its levels. Modern culinary processes such as texturization (with agar-agar) and spherification (with alginate) also interfered with its release. Grilling and gelling using gelatin enhanced eritadenine's bioaccessibility in an in vitro digestion model. An animal model (where male and female rats were administered 21 and 10 mg per kg animal per day of eritadenine) indicated that intake of the compound was safe under these concentrations; it reached the liver and reduced the atherogenic index (TC/HDL) in rat sera. Thus, it might be used to design a functional food.

The effects of allogenic stem cells in a murine model of hind limb diabetic ischemic tissue.

BACKGROUND: Diabetes is one of the major risk factors for peripheral arterial disease. In patients in whom surgery cannot be performed, cell therapy may be an alternative treatment. Since time is crucial for these patients, we propose the use of allogenic mesenchymal cells. METHODS: We obtained mesenchymal cells derived from the fat tissue of a healthy Sprague-Dawley rat. Previous diabetic induction with streptozotocin in 40 male Sprague-Dawley rats, ligation plus left iliac and femoral artery sections were performed as a previously described model of ischemia. After 10 days of follow-up, macroscopic and histo-pathological analysis was performed to evaluate angiogenic and inflammatory parameters in the repair of the injured limb. All samples were evaluated by the same blind researcher. Statistical analysis was performed using the SPSS v.11.5 program (P < 0.05). RESULTS: Seventy percent of the rats treated with streptozotocin met the criteria for diabetes. Macroscopically, cell-treated rats presented better general and lower ischemic clinical status, and histologically, a better trend towards angiogenesis, greater infiltration of type 2 macrophages and a shortening of the inflammatory process. However, only the inflammatory variables were statistically significant. No immunological reaction was observed with the use of allogeneic cells. DISCUSSION: The application of allogeneic ASCs in a hind limb ischemic model in diabetic animals shows no rejection reactions and a reduction in inflammatory parameters in favor of better repair of damaged tissue. These results are consistent with other lines of research in allogeneic cell therapy. This approach might be a safe, effective treatment option that makes it feasible to avoid the time involved in the process of isolation, expansion and production of the use of autologous cells.

Docosahexaenoic Acid Supplemented Diet Influences the Orchidectomy-Induced Vascular Dysfunction in Rat Mesenteric Arteries.

Over the past few decades, the cardiovascular benefits of a high dietary intake of long-chain polyunsaturated fatty acids (PUFAs), like docosahexaenoic acid (DHA), have been extensively studied. However, many of the molecular mechanisms and effects exerted by PUFAs have yet to be well explained. The lack of sex hormones alters vascular tone, and we have described that a DHA-supplemented diet to orchidectomized rats improve vascular function of the aorta. Based on these data and since the mesenteric artery importantly controls the systemic vascular resistance, the objective of this study was to analyze the effect of a DHA-supplemented diet on the mesenteric vascular function from orchidectomized rats. For this purpose mesenteric artery segments obtained from control, orchidectomized or orchidectomized plus DHA-supplemented diet were utilized to analyze: (1) the release of prostanoids, (2) formation of NO and ROS, (3) the vasodilator response to acetylcholine (ACh), as well as the involvement of prostanoids and NO in this response, and (4) the vasoconstrictor response to electrical field stimulation (EFS), analyzing also the effect of exogenous noradrenaline (NA), and the NO donor, sodium nitroprusside (SNP). The results demonstrate beneficial effects of DHA on the vascular function in orchidectomized rats, which include a decrease in the prostanoids release and superoxide formation that were previously augmented by orchidectomy. Additionally, there was an increase in endothelial NO formation and the response to ACh, in which NO involvement and the participation of vasodilator prostanoids were increased. DHA also reversed the decrease in EFS-induced response caused by orchidectomy. All of these findings suggest beneficial effects of DHA on vascular function by reversing the neurogenic response and the endothelial dysfunction caused by orchidectomy.

Metamizole (dipyrone) effects on sevoflurane requirements and postoperative hyperalgesia in rats.

Unlike non-steroidal anti-inflammatory drugs (NSAIDs), metamizole has poor anti-inflammatory effects; and is suitable for models where analgesia, but not anti-inflammatory effects, is desirable. Like opioids, these drugs produce perioperative analgesia while reducing anaesthetic requirements, but it remains unclear whether they may develop tolerance or hyperalgesia, and thus decrease in analgesic efficacy. The aim was to determine whether tolerance or hyperalgesia to metamizole occurred in rats, and whether the sevoflurane minimum alveolar concentration (MAC) was affected. In a randomized, prospective, controlled study, male Wistar rats ( n = 8 per group) were administered metamizole (300 mg/kg, day 4). Previously, the following treatments were provided: daily metamizole for four days (0-3), morphine (10 mg/kg; positive control, day 0 only) or saline (negative control). The main outcome measures were mechanical (MNT) and warm thermal (WNT) nociceptive quantitative sensory thresholds. The baseline sevoflurane MAC and the reduction produced by the treatments were also determined. The mean (SD) baseline MAC [2.4(0.2)%vol] was decreased by morphine and metamizole by 45(11)% and 33(7)% ( P = 0.000, both), respectively. Baseline MNT [35.4(4.5) g] and WNT [13.2(2.4) s] were decreased by morphine and metamizole: MNT reduction of 22(6)% ( P = 0.000) and 22(7)% ( P = 0.001), respectively and WNT reduction of 34(14)% ( P = 0.000) and 24(13)% ( P = 0.001). The baseline MAC on day 4 was neither modified by treatments nor the MAC reduction produced by metamizole (days 0 and 4; P > 0.05). In conclusion, repeated metamizole administration may produce hyperalgesia, although it may not modify its anaesthetic sparing effect. The clinical relevance of this effect in painful research models requiring prolonged analgesic therapy warrants further investigation.

Aspectos técnicos y utilidades del trasplante pulmonar experimental murino / Technical aspects and benefits of experimental mouse lung transplantation

A lo largo de las últimas décadas, el número de trasplantes pulmonares realizados como terapia final de muchas enfermedades respiratorias ha ido creciendo considerablemente, tanto en la población adulta como a nivel pediátrico. Sin embargo, se hace muy necesario estudiar las causas por las que su supervivencia es relativamente baja en comparación con otros trasplantes de órganos. Por ello, desde mediados del siglo pasado comenzaron a realizarse trasplantes pulmonares experimentales, cuya técnica ha ido mejorando, y se ha ampliado a distintas especies animales hasta llegar a los roedores. La ventaja que presentan estas especies pequeñas ha facilitado que el modelo quirúrgico se haya extendido y estandarizado, permitiendo estudiar diferentes aspectos relacionados con las enfermedades respiratorias. En esta revisión se analizan las distintas modalidades técnicas disponibles de trasplante experimental en rata y ratón, destacando tanto la técnica quirúrgica como la anestésica o la monitorización, así como las principales aportaciones generadas por el trasplante pulmonar murino

In recent years, the number of lung transplantations performed as the last option for many respiratory diseases has grown considerably, both in adults and children. However, the causes for the relatively short survival of lungs compared to other organ transplants still need to be studied. Techniques have improved since the 1950s when experimental lung transplantation began, and the different animal species used now include rodents. The advantage of using these small species is that the surgical model has been expanded and standardized, and different respiratory problems can be studied. In this review we examine the different technical strategies used in experimental transplantation in rats and mice, focusing on surgical techniques and anesthesia and monitoring methods, and highlighting the major contributions of mouse lung transplantation to the field

Technical Aspects and Benefits of Experimental Mouse Lung Transplantation. / Aspectos técnicos y utilidades del trasplante pulmonar experimental murino.

In recent years, the number of lung transplantations performed as the last option for many respiratory diseases has grown considerably, both in adults and children. However, the causes for the relatively short survival of lungs compared to other organ transplants still need to be studied. Techniques have improved since the 1950s when experimental lung transplantation began, and the different animal species used now include rodents. The advantage of using these small species is that the surgical model has been expanded and standardized, and different respiratory problems can be studied. In this review we examine the different technical strategies used in experimental transplantation in rats and mice, focusing on surgical techniques and anesthesia and monitoring methods, and highlighting the major contributions of mouse lung transplantation to the field.

Effect of Lidocaine-Ketamine Infusions Combined with Morphine or Fentanyl in Sevoflurane-Anesthetized Pigs.

Providing lidocaine, ketamine, and an opioid greatly decreases the minimum alveolar concentration (MAC) of volatile anesthetics in dogs. However, the efficacy of this combination shows marked interspecies variation, and opioids are likely to be less effective in pigs than in other species. The aim of the study was to determine the effects of constant-rate infusion of lidocaine and ketamine combined with either morphine or fentanyl on the MAC of sevoflurane in pigs. In a prospective, randomized, crossover design, 8 healthy crossbred pigs were premedicated with ketamine and midazolam, and anesthesia was induced and maintained with sevoflurane. Pigs then received ketamine (0.6 mg/kg/h) and lidocaine (3 mg/kg/h) combined with either morphine (0.24 mg/kg/h; MLK) or fentanyl (0.0045 mg/kg/h; FLK) after a loading dose; the control group received Ringers lactate solution. The anesthetic-sparing action of the 2 infusion protocols was calculated according to the MAC, by using dewclaw clamping as the standard noxious stimulus. The sevoflurane MAC (mean ± 1 SD) was 2.0% ± 0.2%, 1.9% ± 0.4%, and 1.8% ± 0.2% in the control, MLK, and FLK groups, respectively. No differences among groups or treatments were found. In conclusion, the administration of MLK or FLK at the studied doses did not reduce the MAC of sevoflurane in pigs.

Difficulties, guidelines and review of developing an acute rejection model after rat intestinal transplantation.

Experimental small bowel transplantation (SBT) in rats has been proven to be a useful tool for the study of ischemia-reperfusion and immunological aspects related to solid organ transplantation. However, the model is not completely refined, specialized literature is scarce and complex technical details are typically omitted or confusing. Most studies related to acute rejection (AR) use the orthotopic standard, with small sample sizes due to its high mortality, whereas those studying chronic rejection (CR) use the heterotopic standard, which allows longer term survival but does not exactly reflect the human clinical scenario. Various animal strains have been used, and the type of rejection and the timing of its analysis differ among authors. The double purpose of this study was to develop an improved unusual AR model of SBT using the heterotopic technique, and to elaborate a guide useful to implement experimental models for studying AR. We analyzed the model's technical details and expected difficulties in overcoming the learning curve for such a complex microsurgical model, identifying the potential problem areas and providing a step-by-step protocol and reference guide for future surgeons interested in the topic. We also discuss the historic and more recent options in the literature.

The Effects of the Toll-Like Receptor 4 Antagonist, Ibudilast, on Sevoflurane's Minimum Alveolar Concentration and the Delayed Remifentanil-Induced Increase in the Minimum Alveolar Concentration in Rats.

BACKGROUND: Ultralow doses of naloxone, an opioid and toll-like receptor 4 antagonist, blocked remifentanil-induced hyperalgesia and the associated increase in the minimum alveolar concentration (MAC), but not tolerance. The aim was to determine the effects of the toll-like receptor 4 antagonist, ibudilast, on the MAC in the rat and how it might prevent the effects of remifentanil. METHODS: Male Wistar rats were randomly allocated to 5 treatment groups (n = 7 per group): 10 mg/kg ibudilast intraperitoneally, 240 µg/kg/h remifentanil IV, ibudilast plus remifentanil, remifentanil plus naloxone IV, or saline. The sevoflurane MAC was determined 3 times in every rat and every day (days 0, 2, and 4): baseline (MAC-A) and 2 further determinations were made after treatments, 1.5 hours apart (MAC-B and MAC-C). RESULTS: A reduction in baseline MAC was produced on day 0 by ibudilast, remifentanil, remifentanil plus ibudilast, remifentanil plus naloxone (P < 0.01), but not saline. Similar effects were found on days 2 and 4. A tolerance to remifentanil was found on days 0, 2, and 4, which neither ibudilast nor naloxone prevented. The MAC increase produced by remifentanil on day 4 (P = 0.001) was prevented by either ibudilast or naloxone. CONCLUSIONS: Ibudilast, besides reducing the MAC, prevented the delayed increase in baseline MAC produced by remifentanil but not the increase in MAC caused by tolerance to remifentanil.

Water-Soluble Compounds from Lentinula edodes Influencing the HMG-CoA Reductase Activity and the Expression of Genes Involved in the Cholesterol Metabolism.

A water extract from Lentinula edodes (LWE) showed HMG-CoA reductase inhibitory activity but contained no statins. NMR indicated the presence of water-soluble α- and ß-glucans and fucomannogalactans. Fractions containing derivatives of these polysaccharides with molecular weight down to approximately 1 kDa still retained their inhibitory activity. Once digested LWE was applied to Caco2 in transport experiments, no significant effect was noticed on the modulation of cholesterol-related gene expression. But, when the lower compartment of the Caco2 monolayer was applied to HepG2, some genes were modulated (after 24 h). LWE was also administrated to normo- and hypercholesterolemic mice, and no significant lowering of serum cholesterol levels was observed; but reduction of triglycerides in liver was observed. However, LWE supplementation modulated the transcriptional profile of some genes involved in the cholesterol metabolism similarly to simvastatin, suggesting that it could hold potential as a hypolipidemic/hypocholesterolemic extract, although further dose-dependent studies should be carried out.

Plasma Cholesterol-Lowering Activity of Lard Functionalized with Mushroom Extracts Is Independent of Niemann-Pick C1-like 1 Protein and ABC Sterol Transporter Gene Expression in Hypercholesterolemic Mice.

Interest in food matrices supplemented with mushrooms as hypocholesterolemic functional foods is increasing. This study was to (i) investigate the hypocholesterolemic activity of lard functionalized with mushroom extracts (LF) including fungal ß-glucans, water-soluble polysaccharides, or ergosterol and (ii) examine the LF influence on transcriptional mechanisms involved in cholesterol metabolism. mRNA levels of 17 cholesterol-related genes were evaluated in jejunum, cecum, and liver of high cholesterol-fed mice. The four tested LFs decreased plasma cholesterol by 22-42%, HDLc by 18-40%, and LDLc by 27-51%, and two of them increased mRNA levels of jejunal Npc1l1 and Abcg5 and hepatic Npc1l1. mRNA levels of other cholesterol-related genes were unchanged. These findings suggest that LF may have potential as a dietary supplement for counteracting diet-induced hypercholesterolemia and could be a source for the development of novel cholesterol-lowering functional foods. However, the cholesterol-lowering effect was unrelated to transcriptional changes, suggesting that post-transcriptional mechanisms could be involved.

Modulation of cholesterol-related gene expression by ergosterol and ergosterol-enriched extracts obtained from Agaricus bisporus.

PURPOSE: To investigate the effect of two extracts obtained from Agaricus bisporus on the mRNA expression of cholesterol-related genes. One of the extracts contained ergosterol and other fungal sterols (SFE) and the other contained ß-glucans and fungal sterols (EßG). METHODS: Firstly, the dietary mixed micelles (DMMs) generated after in vitro digestion of standards and SFE were applied to Caco2 cells. Then, the lower compartment after a Caco2-transport experiment was applied to HepG2 cells. The mRNA expression was assessed in both cell lines by low-density arrays (LDA). Mice received the extracts, ergosterol or control drugs after 4 weeks of a high-cholesterol diet. The lipid profile of plasma, liver and feces was determined. LDA assays were performed in liver and intestines. RESULTS: The DMM fraction of SFE up-regulated the LDLR mRNA expression in Caco2 cells. The lower compartment after Caco2-transport experiments up-regulated LDLR and modulated several other lipid-related genes in HepG2 cells. In mice, SFE decreased TC/HDL ratio and reduced hepatic triglycerides paralleled with down-regulation of Dgat1 expression, while EßG did it without transcriptional changes. Addition of SFE or ergosterol induced in jejunum a similar transcriptional response to simvastatin and ezetimibe; they all down-regulated Srebf2 and Nr1h4 (FXR) genes. CONCLUSION: Ergosterol-containing extracts from A. bisporus lowered hepatic triglyceride and modify the mRNA expression of cholesterol-related genes although the transcriptional regulation was unrelated to changes in plasma lipid profile. These extracts may be useful limiting hepatic steatosis and as bioactive ingredients to design novel functional foods preventing lifestyle-related diseases such as non-alcoholic fatty liver disease.

Growth Hormone Protects the Intestine Preserving Radiotherapy Efficacy on Tumors: A Short-Term Study.

The efficacy of radiotherapy on tumors is hampered by its devastating adverse effects on healthy tissue, particularly that of the gastrointestinal tract. These effects cause acute symptoms that are so disruptive to patients that they can lead to interruption of the radiotherapy program. These adverse effects could limit the intensity of radiation received by the patient, resulting in a sublethal dose to the tumor, thus increasing the risk of tumor resistance. The lack of an effective treatment to protect the bowel during radiation therapy to allow higher radiation doses that are lethal to the tumor has become a barrier to implementing effective therapy. In this study, we present a comparative analysis of both intestinal and tumor tissue in regard to the efficacy and the preventive impact of a short-term growth hormone (GH) treatment in tumor-bearing rats as a protective agent during radiotherapy. Our data show that the exogenous administration of GH improved intestinal recovery after radiation treatment while preserving the therapeutic effect against the tumor. GH significantly increased proliferation in the irradiated intestine but not in the irradiated tumors, as assessed by Positron Emission Tomography and the proliferative markers Ki67, cyclin D3, and Proliferating Cell Nuclear Antigen. This proliferative effect was consistent with a significant increase in irradiated intestinal villi and crypt length. Furthermore, GH significantly decreased caspase-3 activity in the intestine, whereas GH did not produce this effect in the irradiated tumors. In conclusion, short-term GH treatment protects the bowel, inducing proliferation while reducing apoptosis in healthy intestinal tissue and preserving radiotherapy efficacy on tumors.