Sara Berardi

Microbiota modulation counteracts Alzheimer’s disease progression influencing neuronal proteolysis and gut hormones plasma levels

Gut microbiota has a proven role in regulating multiple neuro-chemical pathways through the highly interconnected gut-brain axis. Oral bacteriotherapy thus has potential in the treatment of central nervous system-related pathologies, such as Alzheimer’s disease (AD). Current AD treatments aim to prevent onset, delay progression and ameliorate symptoms. In this work, 3xTg-AD mice in the early stage of AD were treated with SLAB51 probiotic formulation, thereby affecting the composition of gut microbiota and its metabolites. This influenced plasma concentration of inflammatory cytokines and key metabolic hormones considered therapeutic targets in neurodegeneration. Treated mice showed partial restoration of two impaired neuronal proteolytic pathways (the ubiquitin proteasome system and autophagy). Their cognitive decline was decreased compared with controls, due to a reduction in brain damage and reduced accumulation of amyloid beta aggregates. Collectively, our results clearly prove that modulation of the microbiota induces positive effects on neuronal pathways that are able to slow down the progression of Alzheimer’s disease.

First detection of Cytauxzoon spp. infection in European wildcats (Felis silvestris silvestris) of Italy

Cytauxzoonosis is an emerging, tick-transmitted, protozoan disease affecting domestic and wild felids and caused by Cytauxzoon felis, Cytauxzoon manul and Cytauxzoon spp. This study aimed to determine the presence of infection with Cytauxzoon spp. in Felis silvestris silvestris in Italy, in order to enhance the comprehension of its pattern distribution among domestic cat populations. In addition, wildcats were tested for other endemic vector-borne pathogens in Italy. The carcasses of 21 F. s. silvestris were collected from central and northern regions of Italy. All the animals were submitted to necropsy and samples of the spleens were collected. Cytauxzoon infection was surveyed by a conventional PCR amplifying a portion of the SSU-rDNA of species of Piroplasmida. The samples were also screened for Anaplasma spp., Ehrlichia spp., Rickettsia spp., Babesia spp., Theileria spp., and Leishmania spp. using SYBR Green Real-Time PCR (rPCR) assays. Four animals (19%) were positive for Piroplasmida-PCR assay and three sequenced amplicons were obtained (14.3%), clustering with the Italian, Spanish, French and Romanian Cytauxzoon spp. isolates and with C. manul found in Mongolia. The samples were negative for the other pathogens screened. The present results showed that Cytauxzoon spp. may infect both F. s. silvestris and F. s. catus.

SLAB51 Probiotic Formulation Activates SIRT1 Pathway Promoting Antioxidant and Neuroprotective Effects in an AD Mouse Model

The gut-brain axis is a bidirectional communication network functionally linking the gut and the central nervous system (CNS). Based on this, the rational manipulation of intestinal microbiota represents a novel attractive therapeutic strategy for the treatment of CNS-associated disorders. In this study, we explored the properties of a probiotic formulation (namely SLAB51) in counteracting brain oxidative damages associated with Alzheimer’s disease (AD). Specifically, transgenic AD mice (3xTg-AD) were treated with SLAB51 and the effects on protein oxidation, neuronal antioxidant defence and repair systems were monitored, with the particular focus on the role of SIRT1-related pathways. We demonstrated that SLAB51 markedly reduced oxidative stress in AD mice brain by activating SIRT1-dependent mechanisms, thus representing a promising therapeutic adjuvant in AD treatment.

Severe Gastritis with Double Helicobacter spp. Infection Associated with Barrett's Esophagus in a Cheetah

To the Editor, Gastric infection secondary to Helicobacter spp. is frequent in both humans and many animal species. Therefore, the better understanding of these infections in animals may be also useful as a model for human diseases, and to increase knowledge on potentially transmissible conditions. For instance, recent genomic studies suggest that several species of large felids may have acquired Helicobacter infections through predation on early humans [1]. Although gastritis is rare in wild cheetahs despite the presence of abundant spiral bacteria, worldwide the majority of captive cheetahs (Acinonyx jubatus) have a progressive gastritis associated with a specific Helicobacter infection (Helicobacter acinonyx), and such infection represents a major cause of death or the reason for euthanasia [2]. There are many studies on Helicobacter-induced gastritis in cheetahs; however, to the best of our knowledge, there are no studies of esophagitis related to chronic vomiting due to gastritis in such species. A 7-year-old male cheetah hosted at Falconara zoo underwent upper endoscopy due a history of vomiting after food intake since the age of 3 months, vomiting that in the last months increased to an episode two hours after every meal, with deterioration of the clinical conditions. Endoscopy revealed hiatal hernia (about 4 cm diameter) and severe esophagitis of the lower esophagus associated with slightly raised and fragile mucosa well demarcated from the remaining mucosa and extending upward for about 4 cm starting from the esophago-gastric junction. The stomach revealed diffuse erythema. Multiple biopsies were taken from both the esophagus and the gastric mucosa. Three lm thick sections were stained with hematoxylin and eosin, periodic acid-Schiff–alcian blue (pH 2.5), and Giemsa. Barrett’s esophagus was diagnosed by identifying columnar epithelium in specimens taken more than 3 cm above the cardia. The activity of the inflammatory process was evaluated by grouping the specimens into three categories: inactive chronic inflammation, with no polymorphonuclear leukocytes (PMNs) in the lamina propria; active chronic inflammation when PMNs were present in the lamina propria with intra-epithelial infiltration; and erosion-ulceration in terms of the fibrinoleukocytic exudate observed. Helicobacter-like organisms (HLOs) were identified from their morphological characteristics using Giemsa stain at a magnification of x 400 (concentration) and x1000 (morphology). Then, the presence of spiral-shaped bacteria was also confirmed by immunohistochemistry, using a polyclonal antibody (rabbit polyclonal anti-H. pylori – DAKO, Denmark). The degree of infection was determined as mild moderate or severe by using a similar visual analog scale for canine gastric biopsy specimens as proposed by Happonen et al. [3]. Esophageal histology was characterized by hyperplasia of the epithelial basal layer. As a result of the hyperplasia, the deeper and thicker papillae occupied more than two-thirds of the mucosal layer. Some of the squamous epithelium was replaced by metaplastic epithelium (Fig. 1A) with abundance of goblet columnar cells that were periodic acid-Schiff (PAS)-positive, and columnar cells with a brush border and few cytoplasmic vacuoli similar to small intestinal epithelium (Fig. 1B). These cells were organized in rough, pseudo-villous structures lacking absorptive capacity (i.e., prismatic absorptive cells were absent, indicative of incomplete intestinal metaplasia), and they contained areas of cardial gastric epithelium characterized by atrophic mucous glands. The presence of spiral-shaped bacteria in metaplastic glandular cardial gastric epithelium was evidenced by immunohistochemistry (Fig. 1B, insert). A moderate inflammatory infiltrate of lymphocytes, plasma cells, and rare PMNs was observed in the mucosa, sometimes penetrating among pavement cells. Rare fundic glands with parietal cells were also seen. Inflammatory cells (i.e., neutrophils, lymphocytes, plasma cells) were also present among the epithelial cells. An intense inflammatory infiltrate of lymphocytes, plasma cells, and rare macrophages was present in the underlying stroma (Fig. 1A). According to Terio et al. [4], the stomach displayed diffuse severe gastritis, with large numbers of inflammatory cells in both the superficial and deep regions of the lamina propria, as well as abundant intra-epithelial lymphocytes. Inflammatory cells consisted predominately of lymphocytes and plasma cells with variable numbers of large globule leukocytes. Disruption of normal glandular structure, loss of parietal cells (many of which were sloughed and within gland lumens), and necrosis were also present. Intraglandular

Loss of alpha-smooth muscle actin expression associated with chronic intestinal pseudo-obstruction in a young Miniature Bull Terrier

BackgroundChronic intestinal pseudo-obstruction (CIPO) is a rare clinical syndrome in veterinary medicine characterized by severe intestinal dysmotility without evidence of mechanical occlusion of the intestinal lumen. The exact pathogenesis of CIPO is unknown.Case presentationA 1-year-old male Miniature Bull Terrier dog was presented with a history of chronic weight loss, regurgitation, lethargy, vomiting and diarrhea. The dog was submitted for exploratory laparotomy. A full thickness intestinal biopsy was taken and a CIPO was suspected. The clinical condition deteriorated and the dog was euthanized. At gross examination the small intestine was severely dilated. Histologically severe fibrosis of the submucosa and severe atrophy of the tunica muscularis were present in small intestine and colon. Immunohistochemical examination with a panel of antibodies for gastro-intestinal neuromuscular disease-associated antigens revealed a severely reduced expression of alpha-smooth muscle actin in the tunica muscularis.ConclusionsThis case report describes the gross, histological and immunohistochemical findings of CIPO affecting a 1-year-old Miniature Bull Terrier; on the basis of these findings a myopathic form of CIPO is hypothesized in this case.

Neck Kaposiform haemangioendothelioma in a Fischer’s lovebird (Agapornis fischeri)

A six-year-old female Fischers lovebird (Agapornis fischeri) presented at necropsy with a cutaneous mass on the neck, 3.5cm in diameter, yielding and with blood content. Histopathological findings showed a neoplasm characterized by proliferation of vascular endothelial cells. The histology of the mass revealed a multinodular, focally infiltrating tumor. Deeper dermal nodules were made of spindle cells forming vascular slits reminiscent of the histology seen in Kaposis sarcoma (KS). More superficially located dermal nodules consisted of small blood vessels, with histology resembling capillary hemangioma. The spindle cells and capillaries were strongly positive for Vimentin, endothelial cell marker CD31, and negative for sarcomeric α-smooth muscle actin (α-SMA). Intravascular platelet trapping and Periodic acid-Schiff (PAS)-positive hyaline globules were also observed. Differential diagnosis included Kaposis sarcoma, capillary haemangioma, spindle cell haemangioendothelioma, and epithelioid haemangioendothelioma. Based on morphological and immunohistochemical findings, the tumor was diagnosed as a cutaneous Kaposiform haemangioendothelioma (KHE), a rare, low-grade malignant vascular neoplasm. Other organs showed no abnormalities. PCR amplifications, conducted using Kaposis sarcoma-associated herpesvirus (KSHV)-specific primers and degenerate sets of primers designed to detect and characterize members of the Herpesviridae, on DNA extracted from tumor tissue and from whole blood failed to amplify any KSHV-related sequence. Moreover, no specific signal was obtained using primers for detection of psittacine herpesvirus, known to be linked to Pachecos disease in parrots. To the best of our knowledge, this unusual case is the third report of KHE in a non-human animal species, the first described in a bird.