Vincenzo Mastellone

Yellow mealworm larvae (Tenebrio molitor, L.) as a possible alternative to soybean meal in broiler diets

Abstract The aim of the study was to evaluate the feasibility of replacing soybean meal (SBM) with Tenebrio molitor larvae (TML) meal in broiler diets. A total of 80 30-d-old male Shaver brown broilers were divided into two groups fed on two isoproteic and isoenergetic diets differing for protein source (SBM vs. TML). Up to 62 d of age, body weight and feed intake were recorded weekly and body weight gain, feed conversion ratio (FCR), protein efficiency ratio (PER) and European efficiency factor (EEF) were calculated. At 62 d, blood samples were collected from 16 birds/group for evaluation of blood profiles. Feed intake was not different between groups considering the entire period of the trial. The FCR was more favourable in the TML than SBM group from 46 d of age and in the entire period of the trial (4.13 vs. 3.62). The PER was higher in the SBM than in the TML group (1.92 vs. 1.37) while the EEF was higher in broilers fed on the TML diet (132.6 vs. 156.2). Albumin-to-globulin ratio was higher in broilers fed on SBM than in the other group (0.44 vs. 0.30). aspartate aminotransferase and alanine aminotransferase were higher in TML than SBM (195.1 vs. 178.6 U/l and 82.07 vs. 46.71 U/l, respectively). Uric acid was higher in broilers fed on SBM than TML (5.40 vs. 4.16 mg/dl). TML did not affect feed intake and growth rate of broilers from 30 to 62 d of age when compared to an isoproteic and isoenergetic SBM diet, but FCR of the TML group was more favourable than that of the SBM group. The lowest albumin-to-globulin ratio in broilers fed on TML suggests a higher immune response, probably due to the prebiotic effects of chitin.

Serotonin transporter gene deficiency is associated with sudden death of newborn mice through activation of TGF-β1 signalling

The serotonin transporter (SERT) gene has been proposed as a candidate gene responsible for the sudden infant death syndrome (SIDS). In this study, for the first time we obtained a SERT-knockout (KO) mouse model which reproduces SIDS phenotype. SERT-KO mice were generated by mating SERT(Cre/+) heterozygous mice. The SERT-KO mouse embryos at the pre-natal stage E18.5 were lacking of SERT mRNA and protein expression in the heart. A premature death of 75% of SERT-KO mice occurred in the first week after birth. LacZ staining of whole mounts and tissue sections of the heart from SERT(Cre/+);ROSA26R adult mice and E18.5 embryos demonstrated a marked localized expression of SERT in the right ventricle, the conal region, the vasculature, the atrial septum, the ventricular valves, and the sinoatrial node of the conduction system. These data suggest a cardiac phenotype for the sudden death of SERT-KO mice. Histological analysis of heart sections showed that SERT-KO mice develop cardiac fibrosis. Increased collagen accumulation in the myocardium and the valvular and perivascular regions, and enhanced expression of alpha-smooth muscle actin were detected in the heart of SERT-KO mice versus wild-type (WT) mice. Interestingly, higher expression levels of the 5-HT2A receptor and increased levels of phospho-SMAD2/3 and phospho-ERK1/2 were detected in SERT-KO mouse heart versus WT mice. Overall, our findings provide i) new insights into the role of SERT gene in SIDS, and ii) the first in vivo validation of the molecular mechanism involving the activation of TGF-beta1 signalling in the cardiac fibrosis.

Intracellular signaling cascades triggered by the NK1 fragment of hepatocyte growth factor in human prostate epithelial cell line PNT1A

Hepatocyte Growth Factor (HGF)/c-MET signaling has an emerging role in promoting cell proliferation, survival, migration, wound repair and branching in a variety of cell types. HGF plays a crucial role as a mediator of stromal-epithelial interactions in the normal prostate but the precise biological function of HGF/c-Met interaction in the normal prostate and in prostate cancer is not clear. HGF has two naturally occurring splice variants and NK1, the smallest of these HGF variants, consists of the HGF amino terminus through the first kringle domain. We evaluated the intracellular signaling cascades and the morphological changes triggered by NK1 in human prostate epithelial cell line PNT1A which shows molecular and biochemical properties close to the normal prostate epithelium. We demonstrated that these cells express a functional c-MET, and cell exposure to NK1 induces the phosphorylation of tyrosines 1313/1349/1356 residues of c-MET which provide docking sites for signaling molecules. We observed an increased phosphorylation of ERK1/2, Akt, c-Src, p125FAK, SMAD2/3, and STAT3, down-regulation of the expression of epithelial cell-cell adhesion marker E-cadherin, and enhanced expression levels of mesenchymal markers vimentin, fibronectin, vinculin, α-actinin, and α-smooth muscle actin. This results in cell proliferation, in the appearance of a mesenchymal phenotype, in morphological changes resembling cell scattering and in wound healing. Our findings highlight the function of NK1 in non-tumorigenic human prostatic epithelial cells and provide a picture of the signaling pathways triggered by NK1 in a unique cell line.

Heart valve cardiomyocytes of mouse embryos express the serotonin transporter SERT

Multiple evidence demonstrate a role for serotonin and its transporter SERT in heart valve development and disease. By utilizing a Cre/loxP system driven by SERT gene expression, we recently demonstrated a regionally restricted distribution of SERT-expressing cells in developing mouse heart. In order to characterize the cell types exhibiting SERT expression within the mouse heart valves at early developmental stages, in this study we performed immunohistochemistry for Islet1 (Isl1) and connexin-43 (Cx-43) on heart sections from SERT(Cre/+);ROSA26R embryos previously stained with X-gal. We observed the co-localization of LacZ staining with Isl1 labelling in the outflow tract, the right ventricle and the conal region of E11.5 mouse heart. Cx-43 labelled cells co-localized with LacZ stained cells in the forming atrioventricular valves. These results demonstrate the cardiomyocyte phenotype of SERT-expressing cells in heart valves of the developing mouse heart, thus suggesting an active role of SERT in early heart valve development.

Expression of orexin A and its receptor 1 in the choroid plexuses from buffalo brain

The hypothalamic peptide orexin A, deriving from the proteolytic cleavage of the precursor molecule prepro-orexin, has a wide range of physiological effects including the regulation of feeding behaviour, neuroendocrine functions, sleep-wake cycle, and energy homeostasis. Lowered excretion of orexin A into the cerebrospinal fluid (CSF) plays a pathological role in animal and human narcolepsy. Altered levels of orexin A into the CSF have been also found in numerous disorders of the central nervous system, including Parkinsons and Huntingtons disease, dementia, and depressive disorders. While the localization of orexin A and its receptor 1, OX(1), has been elicited in many regions of the mammalian brain and in peripheral organs, there are no information on the expression of the neuropeptide and its receptor 1 in the choroid plexuses (CPs) producing the CSF. In this study, we investigated the expression of orexin A and OX(1) in the CPs from the brain of an adult mammalian species, Bubalis bubalis, by immunogold-labelling in scanning electron microscopy. Both orexin A and OX(1) immuno-reactivity appeared to be widely distributed on the surface of choroid epithelium. Interestingly, a marked orexin A labelling was detected in the areas surrounding the CP blood capillaries. The expression of prepro-orexin and OX(1) mRNA transcripts of 200 and 300 bp, respectively, was assessed in the CPs by reverse-transcription polymerase chain reaction, while Western blotting analysis confirmed the presence of these two proteins in the tissue. Our findings provide the first evidence for orexin A and OX(1) expression in the CPs from mammalian brain, and suggest that the levels of orexin A into the CSF are probably regulated by CP activity.

Growth performance, blood profiles and carcass traits of Barbary partridge (Alectoris barbara) fed two different insect larvae meals (Tenebrio molitor and Hermetia illucens)

To investigate the effect of two insect meals (from Hermetia illucens, HI and Tenebrio molitor, TM larvae) on productive performance and blood profiles of Barbary partridge, ninety, seven days old partridges were divided into 5 groups (6 replicates, 3 partridges/replicate). Up to 64d, the groups fed 5 isoproteic and isoenergetic diets: the control fed a corn-soybean meal diet (SBM group); in TM25 and TM50 groups the 25 and 50% of SBM proteins were substituted by the protein from TM, respectively; in HI25 and HI50 groups the 25 and 50% of SBM were substituted by the protein from HI, respectively. The birds fed TM25 and both the HI levels reached a higher (P<0.01) live weight at 64d than the control. Considering the entire experimental period the TM groups had a more favorable FCR than SBM. The carcass weights of all the insect groups were higher (P<0.01) than the control. The weight of the full digestive tract in SBM group was the highest (P<0.01). The caecal weight, the intestinal and caecal length were the highest (P<0.01) in the SBM group. The SBM group the highest value of albumin/globulin (P<0.01) and creatinine (P<0.05). TM seems to be more effective than HI in improving FCR. The reduced albumin/globulin ratio in the insect meal fed groups could be ascribed to the chitin content and this result was not affected by the amount of chitin intake, suggesting that also the lowest values are able to express their potential effects in partridges.

Expression of the serotonin transporter SERT in the genital tract of cattle.

Both prostate and vestibular glands of mammals contain neuroendocrine cells which synthesize, store and release growth factors including neuropeptides and biogenic amines such as serotonin. An increase of the secretory products by these cells has been correlated to tumour progression and poor prognosis. Serotonin mediates a wide range of physiological functions by binding to multiple receptors on cell surface. However, the entire serotonergic system is mainly regulated by the serotonin transporter SERT which modulates serotonin concentration in extracellular fluid. Primarily located in serotonergic neurons, SERT is also expressed in various cell types in the periphery. In this study, we found a wide distribution of SERT in the parenchymal cells of both the prostate and the vestibular glands of cattle using immunohistochemistry. The expression of SERT mRNA transcripts was assessed by reverse-transcription polymerase chain reaction, thus suggesting that SERT is locally synthesized. Furthermore, Western blotting analysis showed the presence of two isoforms of the protein (70 and 140 kDa), probably corresponding to the high mannose-type SERT and its dimeric form. Our results provide the first evidence for SERT expression in the mammalian genital tract, thus highlighting a new potential target for the therapy of the genital tract cancers.

Expression of the Serotonin Transporter (SERT) in the Choroid Plexuses from Buffalo Brain

Choroid plexuses (CPs) play pivotal roles in a wide range of processes that establish, survey, and maintain the biochemical and cellular status of the central nervous system. Mammalian CPs contain a very high density of serotonin receptors, and serotonin has been shown to affect CP functions. The serotonin transporter (SERT) regulates the entire serotonergic system, including serotonin receptors by means of modulation of serotonin concentration in the extracellular fluid. In this study, the expression of SERT in the CPs from the brain of a mammalian species, Bubalis bubalis, was established. By immunogold labeling in scanning electron microscopy, SERT immunoreactivity was found to be localized on the apical surface of the choroid epithelium. In particular, SERT positivity was detected on the apical portion of villi, and both on the membrane and in the cytoplasm of grouped cells on the surface of the choroid epithelium. Significantly, no SERT was detected in blood vessels irrigating the CPs. The expression of SERT mRNA transcripts of 440 bp in the CPs was detected by reverse‐transcription polymerase chain reaction, and Western blotting analysis revealed the presence of three isoforms of the protein with molecular masses of approximately 70, 80, and 140 kDa, respectively, probably corresponding to differently glycosylated SERT. Our findings provide the first report of SERT detection in the CPs of buffalo brain and indicate that this protein is locally synthesized from the choroid epithelial cells. We suggest that SERT might have an important role in mammalian CPs, possibly regulating the serotonin flow between brain and rest of the body. Anat Rec, 2007.

Effect of spray application of Lactobacillus plantarum on in vivo performance, caecal fermentations and haematological traits of suckling rabbits

Two days before kindling, 228 New Zealand White rabbit does were homogeneously divided into two groups (114 does per group) and fed the same diet. After delivery, the litters were equalized to 8 pups. From 1 to 35 days of age (weaning), the control group (CONT) did not receive any treatment while in the experimental group (LAC) the nests were sprayed with a commercial product containing lyophilized Lactobacillus plantarum dissolved in water (12 g/L). L. plantarum was sprayed on the litters (5 mL per rabbit) once a day during seven consecutive days after delivery. After one week of rest, the treatment was repeated for another week according to the same experimental protocol. Mortality rate, recorded on all the litters (912 rabbits per group) was significantly lower in the LAC group (9.9 vs 17.2%; P<0.05). There were no significant differences in in vivo performance of the 24 litters per group, and rabbits of both groups reached a similar weight at weaning (938 vs 932 g for LAC and CONT groups, respectively). Rabbits from the LAC group showed fermentative activity of caecal microflora (total volatile fatty acids 24.8 vs 14.5 mmol/L; P<0.01) and higher percentage of lymphocytes (73.7 vs 63.9% of total white blood cells; P<0.05). Among the microflora population of rabbit caecal content from the LAC group, it was possible to identify L. plantarum (1.25×106 CFU/g). It might be supposed that the changes in caecal microflora can affect our results and improve the sanitary status of Lactobacillus-sprayed rabbits in the period 1–35 days of age.

Fate Map of Serotonin Transporter-Expressing Cells in Developing Mouse Thyroid

A Cre/loxP‐based fate mapping approach was used to follow the regions of the mouse thyroid labeled by the serotonin transporter SERT. Reporter gene expression (lacZ) is activated by Cre expression from the SERT locus in SERTCre/+;ROSA26R compound mouse embryos. Cell labeling, first detected in the thyroid primordium at the E10.5 prenatal stage, was followed until the postnatal day P30. The co‐localization of lacZ staining in the same cells that express the transcription factors Nkx2.1 and Pax8 at the E12.5 stage confirms their identity as thyroid cell precursors. SERT immunohistochemistry on thyroid sections of E18.5 embryos showed SERT expression in thyroid follicular cells. Western blotting analysis confirmed the expression of the protein in adult thyroid tissue and cultured FRTL‐5 cells. These results describe the fate of SERT‐expressing cells during thyroid development, suggesting an active role of SERT in the development and functions of mammalian thyroid. They also highlight the possibility to use the SERT‐Cre mouse line as a good Cre driver in early thyroid development. Anat Rec, 2011.