Audiogenic epileptic DBA/2 mice strain as a model of genetic reflex seizures and SUDEP

Epilepsy is a chronic neurological disease characterized by abnormal brain activity, which results in repeated spontaneous seizures. Sudden unexpected death in epilepsy (SUDEP) is the leading cause of seizure-related premature death, particularly in drug-resistant epilepsy patients. The etiology of SUDEP is a structural injury to the brain that is not fully understood, but it is frequently associated with poorly controlled and repeated generalized tonic–clonic seizures (GTCSs) that cause cardiorespiratory and autonomic dysfunctions, indicating the involvement of the brainstem. Both respiratory and cardiac abnormalities have been observed in SUDEP, but not much progress has been made in their prevention. Owing to the complexity of SUDEP, experimental animal models have been used to investigate cardiac and/or respiratory dysregulation due to or associated with epileptic seizures that may contribute to death in humans. Numerous rodent models, especially mouse models, have been developed to better understand epilepsy and SUDEP physiopathology. This review synthesizes the current knowledge about dilute brown agouti coat color (DBA/2) mice as a possible SUDEP model because respiratory arrest (RA) and sudden death induced by audiogenic generalized seizures (AGSs) have been observed in these animals. Respiratory/cardiac dysfunction, brainstem arousal system dysfunction, and alteration of the neurotransmitter systems, which are observed in human SUDEP, have also been observed in these mice. In particular, serotonin (5-HT) alteration and adenosine neurotransmission appear to contribute to not only the pathophysiological mechanisms of medication but also seizure-related respiratory dysfunctions in this animal model. These neurotransmitter systems could be the relevant targets for medication development for chronic epilepsy and SUDEP prevention. We reviewed data on AGSs in DBA/2 mice and the relevance of this model of generalized tonic–clonic epilepsy to human SUDEP. Furthermore, the advantages of using this strain prone to AGSs for the identification of possible new therapeutic targets and treatment options have also been assessed

Microbial colonization at the implant-abutment interface and its possible influence on periimplantitis: A systematic review and meta-analysis

PURPOSE The aim of this systematic review and meta-analysis was to evaluate the microbial colonization at the implant-abutment interfaces (IAI) on bone-level implants and to identify possible association with peri-implant conditions. STUDY SELECTION The focus question aimed to answer whether two-piece osseointegrated implants, in function for at least 1 year, in human, relate to higher bacterial count and the onset of periimplantitis, compared to healthy peri-implant conditions. Search strategy encompassed the on-line (MedLine, Google scholar, Cochrane library) literature from 1990 up to March 2015 published in English using combinations of MeSH (Medical Subject Headings) and search terms. Quality assessment of selected full-text articles was performed according to the ARRIVE and CONSORT statement guidelines. For data analysis, the total bacterial count of Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola, Prevotella intermedia, and Fusobacterium nucleatum was calculated and compared to IAI with or without peri-implant pathology. RESULTS A total of 14 articles, reporting data from 1126 implants, fulfilled the inclusion criteria and subjected to quality assessment. The selected studies revealed contamination of the IAI, in patients who received two-piece implant systems. Meta-analysis indicated significant difference in total bacterial count between implants affected by periimplantitis versus healthy peri-implant tissues (0.387±0.055; 95% CI 0.279-0.496). Less bacterial counts were identified in the healthy IAI for all the investigated gram-negative bacteria except for T. forsythia. CONCLUSIONS Significantly higher bacterial counts were found for periodontal pathogenic bacteria within the IAI of implants in patients with periimplantitis compared to those implants surrounded by healthy peri-implant tissues

Image1_Seizure susceptibility to various convulsant stimuli in the BTBR mouse model of autism spectrum disorders.TIFF

Background: Autism spectrum disorders (ASDs) are one of the most severe chronic childhood disorders in terms of prevalence, morbidity, and impact on society. Interestingly, several systematic reviews and meta-analyses documented a bidirectional link between epilepsy and ASD, supporting the hypothesis that both disorders may have common neurobiological pathways. According to this hypothesis, an imbalance of the excitatory/inhibitory (E/I) ratio in several brain regions may represent a causal mechanism underpinning the co-occurrence of these neurological diseases.Methods: To investigate this bidirectional link, we first tested the seizure susceptibility to chemoconvulsants acting on GABAergic and glutamatergic systems in the BTBR mice, in which an imbalance between E/I has been previously demonstrated. Subsequently, we performed the PTZ kindling protocol to study the impact of seizures on autistic-like behavior and other neurological deficits in BTBR mice.Results: We found that BTBR mice have an increased susceptibility to seizures induced by chemoconvulsants impairing GABAA neurotransmission in comparison to C57BL/6J control mice, whereas no significant difference in seizure susceptibility was observed after administration of AMPA, NMDA, and Kainate. This data suggests that deficits in GABAergic neurotransmission can increase seizure susceptibility in this strain of mice. Interestingly, BTBR mice showed a longer latency in the development of kindling compared to control mice. Furthermore, PTZ-kindling did not influence autistic-like behavior in BTBR mice, whereas it was able to significantly increase anxiety and worsen cognitive performance in this strain of mice. Interestingly, C57BL/6J displayed reduced sociability after PTZ injections, supporting the hypothesis that a tight connection exists between ASD and epilepsy.Conclusion: BTBR mice can be considered a good model to study epilepsy and ASD contemporarily. However, future studies should shed light on the mechanisms underpinning the co-occurrence of these neurological disorders in the BTBR model.</p

Ranolazine Attenuates Brain Inflammation in a Rat Model of Type 2 Diabetes

Recent studies suggest a pathogenetic association between metabolic disturbances, including type 2 diabetes (T2DM), and cognitive decline and indicate that T2DM may represent a risk factor for Alzheimer’s disease (AD). There are a number of experimental studies presenting evidence that ranolazine, an antianginal drug, acts as a neuroprotective drug. The aim of the present study was to evaluate the effects of ranolazine on hippocampal neurodegeneration and astrocytes activation in a T2DM rat model. Diabetes was induced by a high fat diet (HFD) and streptozotocin (STZ) injection. Animals were divided into the following groups: HFD/STZ + Ranolazine, HFD/STZ + Metformin, HFD/STZ + Vehicle, NCD + Vehicle, NCD + Ranolazine and NCD + Metformin. The presence of neurodegeneration was evaluated in the hippocampal cornus ammonis 1 (CA1) region by cresyl violet staining histological methods, while astrocyte activation was assessed by western blot analysis. Staining with cresyl violet highlighted a decrease in neuronal density and cell volume in the hippocampal CA1 area in diabetic HFD/STZ + Vehicle rats, while ranolazine and metformin both improved T2DM-induced neuronal loss and neuronal damage. Moreover, there was an increased expression of GFAP in the HFD/STZ + Vehicle group compared to the treated diabetic groups. In conclusion, in the present study, we obtained additional evidence supporting the potential use of ranolazine to counteract T2DM-associated cognitive decline

Metabolic and cognitive effects of ranolazine in type 2 diabetes mellitus. data from an in vivo model

Type 2 diabetes mellitus (T2DM) is a risk factor for cognitive impairment. Ranolazine, an anti-ischemic drug used in the treatment of angina pectoris, has been shown to possess hypoglycemic properties in pre-clinical and clinical studies. The aim of this study was to evaluate the effects of ranolazine on glucose metabolism and cognitive function in a T2DM model of Wistar rats. Diabetes was induced by a high fat diet (HFD) and streptozotocin (STZ). The control group received a normal caloric diet (NCD) and sodium citrate buffer. Metformin, an effective hypoglycemic drug, was employed as a positive control. Animals were divided into the following groups: HFD/STZ + Ranolazine, HFD/STZ + Metformin, HFD/STZ + Vehicle, NCD + Vehicle, NCD + Ranolazine, and NCD + Metformin. Rats received ranolazine (20 mg/kg), metformin (300 mg/kg), or water, for 8 weeks. At the end of the treatments, all animals underwent to an intraperitoneal glucose tolerance test (IPGTT) and behavioral tests, including passive avoidance, novel object recognition, forced swimming, and elevate plus maze tests. Interleukin-6 plasma levels in the six treatment groups were assessed by Elisa assay. Body mass composition was estimated by nuclear magnetic resonance (NMR). Glucose responsiveness significantly improved in the HFD/STZ + Ranolazine (p &lt; 0.0001) and HFD/STZ + Metformin (p = 0.003) groups. There was a moderate effect on blood glucose levels in the NCD + Ranolazine and NCD + Metformin groups. Lean body mass was significantly increased in the HFD/STZ + Ranolazine and HFD/STZ + Metformin animals, compared to HFD/STZ + Vehicle animals. Ranolazine improved learning and long-term memory in HFD/STZ + Ranolazine compared to HFD/STZ + Vehicle (p &lt; 0.001) and ameliorated the pro-inflammatory profile of diabetic mice. These results support the hypothesis of a protective effect of ranolazine against cognitive decline caused by T2DM

Glucagon induces the hepatic expression of inflammatory markers in vitro and in vivo

Glucagon exerts multiple hepatic actions, including stimulation of glycogenolysis/gluconeogenesis. The liver plays a crucial role in chronic inflammation by synthesizing proinflammatory molecules, which are thought to contribute to insulin resistance and hyperglycaemia. Whether glucagon affects hepatic expression of proinflammatory cytokines and acute-phase reactants is unknown. Herein, we report a positive relationship between fasting glucagon levels and circulating interleukin (IL)-1β (r&nbsp;=&nbsp;0.252, p&nbsp;=&nbsp;.042), IL-6 (r&nbsp;=&nbsp;0.230, p&nbsp;=&nbsp;.026), fibrinogen (r&nbsp;=&nbsp;0.193, p&nbsp;=&nbsp;.031), complement component 3 (r&nbsp;=&nbsp;0.227, p&nbsp;=&nbsp;.024) and high sensitivity C-reactive protein (r&nbsp;=&nbsp;0.230, p&nbsp;=&nbsp;.012) in individuals without diabetes. In CD1 mice, 4-week continuous treatment with glucagon induced a significant increase in circulating IL-1β (p&nbsp;=&nbsp;.02), and IL-6 (p&nbsp;=&nbsp;.001), which was countered by the contingent administration of the glucagon receptor antagonist, GRA-II. Consistent with these results, we detected a significant increase in the hepatic activation of inflammatory pathways, such as expression of NLRP3 (p &lt; .02), and the phosphorylation of nuclear factor kappaB (NF-κB; p &lt; .02) and STAT3 (p &lt; .01). In HepG2 cells, we found that glucagon dose-dependently stimulated the expression of IL-1β (p &lt; .002), IL-6 (p &lt; .002), fibrinogen (p &lt; .01), complement component 3 (p &lt; .01) and C-reactive protein (p &lt; .01), stimulated the activation of NLRP3 inflammasome (p &lt; .01) and caspase-1 (p &lt; .05), induced the phosphorylation of TRAF2 (p &lt; .01), NF-κB (p &lt; .01) and STAT3 (p &lt; .01). Preincubating cells with GRA-II inhibited the ability of glucagon to induce an inflammatory response. Using HepaRG cells, we confirmed the dose-dependent ability of glucagon to stimulate the expression of NLRP3, the phosphorylation of NF-κB and STAT3, in the absence of GRA-II. These results suggest that glucagon has proinflammatory effects that may participate in the pathogenesis of hyperglycaemia and unfavourable cardiometabolic risk profile

Biologics for Inflammatory Bowel Disease in Clinical Practice: A Calabria (Southern Italy) Prospective Pharmacovigilance Study

Background: The use of immune-modifying biological agents has markedly changed the clinical course and the management of Inflammatory bowel diseases (IBDs). Active post-marketing surveillance programs are fundamental to early recognize expected and unexpected adverse events (AEs), representing a powerful tool to better determine the safety profiles of biologics in a real-world setting. Methods: This study aimed to identify the occurrence of AEs and therapeutic failures linked to biological drugs used in gastroenterology units during a prospective pharmacovigilance program in Southern Italy. Patients affected by IBDs and treated with a biologic agent, from 1 January 2019, to 31 December 2021 (study period) in three gastroenterology units were enrolled. Results: Overall, 358 patients with a diagnosis of active Crohn&rsquo;s disease or ulcerative colitis satisfying inclusion criteria have been enrolled. Infliximab (IFX) was the most administered drug at the index date (214; 59.8%), followed by Adalimumab (ADA; 89; 24.9%), Golimumab (GOL; 37; 10.3%), Vedolizumab (VDZ; 17; 4.7%) and Ustekimumab (UST; 1; 0.3%). Seventy-three patients (20.4%) experienced at least one AE, while 62 patients (17.3%) had therapeutic ineffectiveness. No serious AEs were reported in the follow-up period in the enrolled patients. AEs have been described with IFX (50/214; p = 0.47), GOL (7/37; p = 0.78), ADA (13/89; p = 0.18), and VDZ (3/17; p = 0.52), no AEs have been noticed with UST (0/1). Conclusions: Based on the low rate of AEs observed and withdrawal from treatment, our data seem to corroborate the favorable beneficial/risk profile of biologics for IBDs

First evidence of altered microbiota and intestinal damage and their link to absence epilepsy in a genetic animal model, the WAG/Rij rat

Objective A large number of studies have highlighted the important role of the gut microbiota in the pathophysiology of neurological disorders, suggesting that its manipulation might serve as a treatment strategy. We hypothesized that the gut microbiota participates in absence seizure development and maintenance in the WAG/Rij rat model and tested this hypothesis by evaluating potential gut microbiota and intestinal alterations in the model, as well as measuring the impact of microbiota manipulation using fecal microbiota transplantation (FMT).Methods Initially, gut microbiota composition and intestinal histology of WAG/Rij rats (a well-recognized genetic model of absence epilepsy) were studied at 1, 4, and 8 months of age in comparison to nonepileptic Wistar rats. Subsequently, in a second set of experiments, at 6 months of age, untreated Wistar or WAG/Rij rats treated with ethosuximide (ETH) were used as gut microbiota donors for FMT in WAG/Rij rats, and electroencephalographic (EEG) recordings were obtained over 4 weeks. At the end of FMT, stool and gut samples were collected, absence seizures were measured on EEG recordings, and microbiota analysis and histopathological examinations were performed.Results Gut microbiota analysis showed differences in beta diversity and specific phylotypes at all ages considered and significant variances in the Bacteroidetes/Firmicutes ratio between Wistar and WAG/Rij rats. FMT, from both Wistar and ETH-treated WAG/Rij donors to WAG/Rij rats, significantly decreased the number and duration of seizures. Histological results indicated that WAG/Rij rats were characterized by intestinal villi disruption and inflammatory infiltrates already at 1 month of age, before seizure occurrence; FMT partially restored intestinal morphology while also significantly modifying gut microbiota and concomitantly reducing absence seizures.Significance Our results demonstrate for the first time that the gut microbiota is modified and contributes to seizure occurrence in a genetic animal model of absence epilepsy and that its manipulation may be a suitable therapeutic target for absence seizure management