Francesca Vitari

The chemical code of porcine enteric neurons and the number of enteric glial cells are altered by dietary probiotics

Background  The enteric nervous system (ENS) contains chemically coded populations of neurons that serve specific functions for the control of the gastrointestinal tract. The ability of neurons to modify their chemical code in response to luminal changes has recently been discovered. It is possible that enteric neuronal plasticity may sustain the adaptability of the gut to changes in intestinal activity or injury, and that gut neurons may respond to an altered intestinal environment by changing their neuropeptide expression.

Changes in nitrosative stress biomarkers in swine intestine following dietary intervention with verbascoside.

In farm animals, oxidative stress can be involved in several intestinal pathological disorders, and many antioxidant molecules, especially those of plant origin, can counteract free radicals, thus stabilizing the gut environment and enhancing health. The aim of the study was to investigate whether the use of verbascoside (VB), a polyphenol plant compound, in pig feeding could modulate oxidative and/or nitrosative stress in the gut. Eighteen male piglets (Dalland) were assigned to two groups, which were fed with either a control diet (CON) or a diet supplemented with 5 mg/kg of verbascoside (VB) for 166 days. At slaughter, duodenum and jejunum specimens were collected. Immunohistochemistry and Western blot analyses were performed on the samples to evaluate free radical adducts, including acrolein (ACR), 8-hydroxydeoxyguanosine (8-OHdg) and nitrotyrosine (NT). A KRL test was also used to assess the total blood antioxidant activity, and no difference was observed. Immunohistochemistry and Western blot showed that dietary treatment decreased the levels of nitrotyrosine in enteroendocrine cell populations(P<0.05). Characterization of the enteroendocrine cell typology was then performed, and serotonin-immunoreactive cells were revealed to be directly involved in decreasing the nitrosative stress status. This preliminary study demonstrates the important role of dietary VB in decreasing stress biomarkers in swine gut, thus highlighting a possible intervention aimed at building a large prospective for antioxidant dietary supplementation in food animal species.

Dietary Conjugated Linoleic Acids Decrease Leptin in Porcine Adipose Tissue

We investigated the effects of dietary conjugated linoleic acids (CLA) on white adipose tissue (WAT) in heavy pigs. Twelve pigs were assigned to 1 of 2 groups supplemented with either 0 or 0.75% of a CLA preparation (isomeric mixture) and were slaughtered at 159 +/- 2.3 kg live weight. Their subcutaneous WAT was analyzed by both chemical and microanatomical methods. The WAT of CLA-fed pigs tended to have a higher protein content (P = 0.064) and smaller adipocytes (P = 0.053) than that of control (CTR) pigs. The number of proliferating preadipocytes tended to be greater (P = 0.076) in pigs fed CLA, whereas the number of apoptotic adipocytes was greater (P < 0.01) than in CTR pig. Immunohistochemistry revealed that leptin (Ob) expression was lower (P = 0.048) in adipocytes from treated pigs and Western blot quantification of Ob revealed lower levels (P < 0.05) in CLA-fed pigs. The Ob receptor was not affected by dietary CLA supplementation. Tyrosine hydroxylase activity was higher (P < 0.001) in WAT of CLA fed-pigs than in CTR. It is conceivable that the increased noradrenergic activity due to dietary CLA decreases the Ob expression, although it does not diminish the lipid content of WAT, at least in heavy pigs. This article describes the interaction between CLA and Ob in the WAT of heavy pigs and we hypothesize that there is an increased noradrenergic stimulation of lipolysis directly in the target tissue.

Burial of piglet carcasses in cement: a study of macroscopic and microscopic alterations on an animal model.

AbstractScarce experimental data exist describing postmortem effects of burial in cement. The scanty literature presents several case reports, but no experimental study. To perform a pilot study, the following experimental system was designed: 4 piglet corpses, who died of natural causes, were encased in concrete. After 1, 2, 3, and 6 months, a block was opened, and autopsy and microscopic analyses were performed. At the first month, initial putrefaction had started, and hindlegs were partly skeletonized. At the second month, both forelegs and hindlegs were partly skeletonized, and the abdomen and back showed advanced putrefaction. At the third month, the samples showed areas of mummification at the abdomen within a general context of initial putrefaction. At the sixth month, the sample showed wide adipocere formation. Histological findings revealed in some analyzed tissues (epithelium, dermis, adipose, and subcutaneous muscular tissues) a well-defined histological pattern even at 3 months after encasement in concrete: this means that microscopic changes may be delayed in concrete and that it may be worth performing histological analyses even in such kind of decomposed material.

Is there adaptation of the exocrine pancreas in wild animal? The case of the Roe Deer

BackgroundPhysiology of the exocrine pancreas has been well studied in domestic and in laboratory animals as well as in humans. However, it remains quite unknown in wildlife mammals. Roe deer and cattle (including calf) belong to different families but have a common ancestor. This work aimed to evaluate in the Roe deer, the adaptation to diet of the exocrine pancreatic functions and regulations related to animal evolution and domestication.ResultsForty bovine were distributed into 2 groups of animals either fed exclusively with a milk formula (monogastric) or fed a dry feed which allowed for rumen function to develop, they were slaughtered at 150 days of age. The 35 Roe deer were wild animals living in the temperate broadleaf and mixed forests, shot during the hunting season and classified in two groups adult and young. Immediately after death, the pancreas was removed for tissue sample collection and then analyzed. When expressed in relation to body weight, pancreas, pancreatic protein weights and enzyme activities measured were higher in Roe deer than in calf. The 1st original feature is that in Roe deer, the very high content in pancreatic enzymes seems to be related to specific digestive products observed (proline-rich proteins largely secreted in saliva) which bind tannins, reducing their deleterious effects on protein digestion. The high chymotrypsin and elastase II quantities could allow recycling of proline-rich proteins. In contrast, domestication and rearing cattle resulted in simplified diet with well digestible components. The 2nd feature is that in wild animal, both receptor subtypes of the CCK/gastrin family peptides were present in the pancreas as in calf, although CCK-2 receptor subtype was previously identified in higher mammals.ConclusionsBovine species could have lost some digestive capabilities (no ingestion of great amounts of tannin-rich plants, capabilities to secrete high amounts of proline-rich proteins) compared with Roe deer species. CCK and gastrin could play an important role in the regulation of pancreatic secretion in Roe deer as in calf. This work, to the best of our knowledge is the first study which compared the Roe deer adaptation to diet with a domesticated animal largely studied.

Bonding of meniscal tissue: a nude mouse repair model

Meniscus repair is a current clinical challenge. Menisci play a fundamental role in knee biomechanics, but they lack intrinsic regenerative properties. Conse quently, when a tear occurs and the meniscus is removed surgically, even partially, crucial changes in knee homeostasis take place, often leading to the development of early osteoarthritis. In recent decades tissue engineering approaches have been advocated to improve the reparative processes of joint tissues. In this study, the bonding capacity of isolated chondrocytes was analysed in a nude mouse meniscus repair model: a swine chondrocyte-fibrin glue suspension was utilised as a biologic glue to improve bonding between two meniscal slices obtained from swine menisci. The composites were wrapped with acellular fibrin glue and implanted in subcutaneous pouches of nude mice for four weeks. Upon retrieval, a firm gross bonding was observed. This was consistent with the histological findings. In particular, a fibrocartilaginous tissue was found at the interface between the meniscal slices, having some penetration buds arising from the neo-tissue. These results demonstrated the potential of this model for improving meniscal bonding. However, further orthotopic studies in a large animal model are needed to evaluate its feasibility in clinical practice.