TSSFinder-fast and accurate ab initio prediction of the core promoter in eukaryotic genomes.

Promoter annotation is an important task in the analysis of a genome. One of the main challenges for this task is locating the border between the promoter region and the transcribing region of the gene, the transcription start site (TSS). The TSS is the reference point to delimit the DNA sequence responsible for the assembly of the transcribing complex. As the same gene can have more than one TSS, so to delimit the promoter region, it is important to locate the closest TSS to the site of the beginning of the translation. This paper presents TSSFinder, a new software for the prediction of the TSS signal of eukaryotic genes that is significantly more accurate than other available software. We currently are the only application to offer pre-trained models for six different eukaryotic organisms: Arabidopsis thaliana, Drosophila melanogaster, Gallus gallus, Homo sapiens, Oryza sativa and Saccharomyces cerevisiae. Additionally, our software can be easily customized for specific organisms using only 125 DNA sequences with a validated TSS signal and corresponding genomic locations as a training set. TSSFinder is a valuable new tool for the annotation of genomes. TSSFinder source code and docker container can be downloaded from http://tssfinder.github.io. Alternatively, TSSFinder is also available as a web service at http://sucest-fun.org/wsapp/tssfinder/.

Hepatic susceptibility to oxidative damage after repeated concomitant exposure to aspartame and aflatoxin B1 in rats.

The potential interactions among food additives/contaminants and the consequences to biological systems is a topic that is rarely addressed in scientific literature. Thus, the current study investigated if the combined administration of ASP and AFB1 would impair hepatic and renal oxidative status. Male Wistar rats received during 14 days once a day ASP (75 mg/Kg) and/or AFB1 (250 µg/Kg) through intragastric route. At the end of experimental protocol, samples of liver and kidneys were collected for assessing biochemical markers of oxidative status. In the hepatic tissue, the treatment with a single substance (ASP or AFB1) caused an increase in TBARS levels, and a reduction in non-enzymatic antioxidant defenses (Vit C and NPSH levels and FRAP test). In the kidneys, TBARS levels were increased only in the group that received ASP + AFB1. The association reduced NPSH content, while the treatment with AFB1 reduced the FRAP levels. GST and CAT activities were increased in all treatments. Overall, ASP and AFB1 association presented higher toxic effects to the tissues. To the best of our knowledge, this is the first study demonstrating that the associated use of both ASP and AFB1 induces more extensive injuries in comparison to the effects caused by each one alone. Therefore, these data demonstrated that concomitant exposure to ASP and AFB1 potentiated their oxidative damage in hepatic tissue, suggesting that this organ is particularly sensitive to the toxic action induced by these substances.

Increased cholinergic activity under conditions of low estrogen leads to adverse cardiac remodeling.

Cholinesterase inhibitors are used in postmenopausal women for the treatment of neurodegenerative diseases. Despite their widespread use in the clinical practice, little is known about the impact of augmented cholinergic signaling on cardiac function under reduced estrogen conditions. To address this gap, we subjected a genetically engineered murine model of systemic vesicular acetylcholine transporter overexpression (Chat-ChR2) to ovariectomy and evaluated cardiac parameters. Left-ventricular function was similar between Chat-ChR2 and wild-type (WT) mice. Following ovariectomy, WT mice showed signs of cardiac hypertrophy. Conversely, ovariectomized (OVX) Chat-ChR2 mice evolved to cardiac dilation and failure. Transcript levels for cardiac stress markers atrial natriuretic peptide (ANP) and B-type natriuretic peptide (BNP) were similarly upregulated in WT/OVX and Chat-ChR2/OVX mice. 17ß-Estradiol (E2) treatment normalized cardiac parameters in Chat-ChR2/OVX to the Chat-ChR2/SHAM levels, providing a link between E2 status and the aggravated cardiac response in this model. To investigate the cellular basis underlying the cardiac alterations, ventricular myocytes were isolated and their cellular area and contractility were assessed. Myocytes from WT/OVX mice were wider than WT/SHAM, an indicative of concentric hypertrophy, but their fractional shortening was similar. Conversely, Chat-ChR2/OVX myocytes were elongated and presented contractile dysfunction. E2 treatment again prevented the structural and functional changes in Chat-ChR2/OVX myocytes. We conclude that hypercholinergic mice under reduced estrogen conditions do not develop concentric hypertrophy, a critical compensatory adaptation, evolving toward cardiac dilation and failure. This study emphasizes the importance of understanding the consequences of cholinesterase inhibition, used clinically to treat dementia, for cardiac function in postmenopausal women.

Changes in the autonomic and respiratory patterns in mice submitted to short-term sustained hypoxia.

NEW FINDINGS: What is the central question of this study? Do mice submitted to sustained hypoxia present autonomic and respiratory changes similarly to rats? What is the main finding and its importance? Arterial pressure in the normal range, reduced baseline heart rate and tachypnoea were observed in behaving sustained hypoxia mice. Recordings in the in situ preparation of mice submitted to sustained hypoxia show an increase in cervical vagus nerve activity and a simultaneous reduction in thoracic sympathetic nerve activity correlated with changes in the respiratory cycle. Therefore, mice are an important model for studies on the modulation of sympathetic activity to the cardiovascular system and the vagus innervation of the upper airways due to changes in the respiratory network induced by sustained hypoxia. ABSTRACT: Short-term sustained hypoxia (SH) in rats induces sympathetic overactivity and hypertension due to changes in sympathetic-respiratory coupling. However, there are no consistent data about the effect of SH on mice due to the different protocols of hypoxia and difficulties associated with the handling of these rodents under different experimental conditions. In situ recordings of autonomic and respiratory nerves in SH mice have not been performed yet. Herein, we evaluated the effects of SH ( FiO2  = 0.1 for 24 h) on baseline mean arterial pressure (MAP), heart rate (HR), respiratory frequency (fR ) and responses to chemoreflex activation in behaving SH mice. A characterization of changes in cervical vagus (cVN), thoracic sympathetic (tSN), phrenic (PN) and abdominal (AbN) nerves in SH mice using the in situ working heart-brainstem preparation was also performed. SH mice presented normal MAP, significant reduction in baseline HR, increase in baseline fR , as well as increase in the magnitude of bradycardic response to chemoreflex activation. In in situ preparations, SH mice presented a reduction in PN discharge frequency, and increases in the time of expiration and incidence of late-expiratory bursts in AbN activity. Nerve recordings also indicated a significant increase in cVN activity and a significant reduction in tSN activity during expiration in SH mice. These findings make SH mice an important experimental model for better understanding how changes in the respiratory network may impact on the modulation of vagal control to the upper airways, as well as in the sympathetic activity to the cardiovascular system.

Re-emergence of Gamma-like-II and emergence of Gamma-S:E661D SARS-CoV-2 lineages in the south of Brazil after the 2021 outbreak.

BACKGROUND: We report a genomic surveillance of SARS-CoV-2 lineages circulating in Paraná, southern Brazil, from March 2020 to April 2021. Our analysis, based on 333 genomes, revealed that the first variants detected in the state of Paraná in March 2020 were the B.1.1.33 and B.1.1.28 variants. The variants B.1.1.28 and B.1.1.33 were predominant throughout 2020 until the introduction of the variant P.2 in August 2020 and a variant of concern (VOC), Gamma (P.1), in January 2021. The VOC Gamma, a ramification of the B.1.1.28 lineage first detected in Manaus (northern Brazil), has grown rapidly since December 2020 and was thought to be responsible for the deadly second wave of COVID-19 throughout Brazil. METHODS: The 333 genomic sequences of SARS-CoV-2 from March 2020 to April 2021 were generated as part of the genomic surveillance carried out by Fiocruz in Brazil Genomahcov Fiocruz. SARS-CoV-2 sequencing was performed using representative samples from all geographic areas of Paraná. Phylogenetic analyses were performed using the 333 genomes also included other SARS-CoV-2 genomes from the state of Paraná and other states in Brazil that were deposited in the GISAID. In addition, the time-scaled phylogenetic tree was constructed with up to 3 random sequences of the Gamma variant from each state in Brazil in each month of 2021. In this analysis we also added the sequences identified as the B.1.1.28 lineage of the Amazonas state and and the Gamma-like-II (P.1-like-II) lineage identified in different regions of Brazil. RESULTS: Phylogenetic analyses of the SARS-CoV-2 genomes that were previously classified as the VOC Gamma lineage by WHO/PANGO showed that some genomes from February to April 2021 branched in a monophyletic clade and that these samples grouped together with genomes recently described with the lineage Gamma-like-II. Additionally, a new mutation (E661D) in the spike (S) protein has been identified in nearly 10% of the genomes classified as the VOC Gamma from Paraná in March and April 2021.Finally, we analyzed the correlation between the lineage and the Gamma variant frequency, age group (patients younger or older than 60 years old) and the clinical data of 86 cases from the state of Paraná. CONCLUSIONS: Our results provided a reliable picture of the evolution of the SARS-CoV-2 pandemic in the state of Paraná characterized by the dominance of the Gamma strain, as well as a high frequencies of the Gamma-like-II lineage and the S:E661D mutation. Epidemiological and genomic surveillance efforts should be continued to unveil the biological relevance of the novel mutations detected in the VOC Gamma in Paraná.

MnSOD Ala16Val polymorphism in cognitive dysfunction in patients with epilepsy: A relationship with oxidative and inflammatory markers.

OBJECTIVE: The objective of the study was to evaluate the neurocognitive profile and its relation with Ala16ValMnSOD polymorphism in epilepsy and if these clinical parameters are linked to oxidative stress and inflammatory markers. METHODS: Patients with epilepsy (n = 31) and healthy subjects (n = 42) were recruited. A neuropsychological evaluation was performed in both groups through a battery of cognitive tests. Oxidative stress, inflammatory markers, apoptotic factors, and deoxyribonucleic acid (DNA) damage were measured in blood samples. RESULTS: Statistical analyses showed the association of MnSOD Ala16Val polymorphism with cognitive impairment, including praxis, perception, attention, language, executive functions, long-term semantic memory, short-term visual memory, and total memory in patients with epilepsy and Valine-Valine (VV) genotype compared with the control group. Compared with the controls and patients with epilepsy, Alanine-Alanine (AA), and Alanine-Valine (AV) genotype, the patients with epilepsy and VV genotype exhibited higher levels of tumor necrosis factor alpha (TNF-α), interleukin 1ß (IL-1ß), interleukin 6 (IL-6), activation of caspases 1 and 3 (CASP-1 and -3), and DNA damage. Our findings also showed higher carbonyl protein and thiobarbituric acid reactive substances (TBARS) levels as well as an increased superoxide dismutase (SOD) and acetylcholinesterase (AChE) activities in patients with epilepsy and VV genotype. CONCLUSION: This study supports the evidence of a distinct neuropsychological profile in patients with epilepsy, especially those with the VV genotype. Furthermore, our results suggest that oxidative and inflammatory pathways may be associated with genetic polymorphism and cognitive dysfunction in patients with epilepsy.

Effect of atorvastatin on behavioral alterations and neuroinflammation during epileptogenesis.

Temporal lobe epilepsy (TLE) is the most frequent and medically refractory type of epilepsy in humans. In addition to seizures, patients with TLE suffer from behavioral alterations and cognitive deficits. Poststatus epilepticus model of TLE induced by pilocarpine in rodents has enhanced the understanding of the processes leading to epilepsy and thus, of potential targets for antiepileptogenic therapies. Clinical and experimental evidence suggests that inflammatory processes in the brain may critically contribute to epileptogenesis. Statins are inhibitors of cholesterol synthesis, and present pleiotropic effects that include antiinflammatory properties. We aimed the present study to test the hypothesis that atorvastatin prevents behavioral alterations and proinflammatory state in the early period after pilocarpine-induced status epilepticus. Male and female C57BL/6 mice were subjected to status epilepticus induced by pilocarpine and treated with atorvastatin (10 or 100mg/kg) for 14days. Atorvastatin slightly improved the performance of mice in the open-field and object recognition tests. In addition, atorvastatin dose-dependently decreased basal and status epilepticus-induced levels of interleukin-1ß (IL-1ß), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and interferon-γ (INF-γ) and increased interleukin-10 (IL-10) levels in the hippocampus and cerebral cortex. The antiinflammatory effects of atorvastatin were qualitatively identical in both sexes. Altogether, these findings extend the range of beneficial actions of atorvastatin and indicate that its antiinflammatory effects may be useful after an epileptogenic insult.

Depressive, inflammatory, and metabolic factors associated with cognitive impairment in patients with epilepsy.

PURPOSE: The purpose of this study was to examine the cognitive function and depressive traits most frequently associated with the clinical assessment of patients with epilepsy and if these clinical parameters are linked to glycolipid levels and inflammatory and apoptotic markers. METHODS: Patients with epilepsy (n = 32) and healthy subjects (n = 41) were recruited to participate in this study. Neuropsychological evaluation was performed in both groups through a battery of cognitive tests. Inflammatory markers, apoptotic factors, and deoxyribonucleic acid (DNA) damage were measured in blood samples. Additionally, the metabolic markers total cholesterol (CHO), low-density lipoprotein (LDL), high-density lipoprotein (HDL), triglyceride (TG), and glucose (GLU) levels were analyzed. RESULTS: Statistical analyses showed that patients with epilepsy presented decreased scores in memory, attention, language, and executive function tests compared with the control group. Analysis revealed that there was negative correlation in epilepsy for seizure duration vs. oral language (R = -0.4484, p < 0.05) and seizure duration vs. problem solving (executive functions) (R = -0.3995, p < 0.05). This was also observed when comparing depression with temporal-spatial orientation (TSO) (R = -0.39, p < 0.05). Furthermore, we observed a higher depression score in patients with epilepsy than in the healthy ones. Statistical analyses showed higher acetylcholinesterase (AChE) (p < 0.05), interleukin 1ß (IL-1ß, p < 0.001), and tumor necrosis factor-alpha (TNF-α) (p < 0.001) levels compared with those in the control group. Moreover, patients with epilepsy had significantly higher serum levels of caspase 3 (CASP 3) (p < 0.001) and Picogreen (p < 0.001) compared with the control subjects. Regarding the metabolic markers, higher glycolipid levels were observed in the patients with epilepsy (CHO < 0.05*, LDL < 0.0001*, TG < 0.05*, GLU p < 0.05). High-density lipoprotein levels were not significant. The patients with epilepsy had significant correlation when comparing total language with TNF-α (R = -0.4, p < 0.05), praxes with CASP 3 (R = -0.52, p < 0.01), total CHO with total language (R = -0.48, p < 0.05), TG with semantic memory (R = -0.54, p < 0.05), TG with prospective memory (R = -0.2165, p < 0.02), TG with total memory (R = -0.53, p < 0.02), and GLU with total attention (R = -0.62, p < 0.002). CONCLUSION: This study supports the evidence of a distinct neuropsychological profile between patients with epilepsy and healthy subjects. Furthermore, our findings suggest that inflammatory pathway, glycolipid profile, and depressive factors may be associated with cognitive dysfunction in patients with epilepsy.

Aflatoxin B1 reduces non-enzymatic antioxidant defenses and increases protein kinase C activation in the cerebral cortex of young rats.

OBJECTIVES: Aflatoxin B1 (AFB1) is the most widespread mycotoxin, and it is a feed contaminant and is highly toxic, causing carcinogenic, mutagenic, and teratogenic effects. Many researches clarified the peripheral effects of the exposition to AFB1; however, there are few studies explaining their effects on central nervous system. The aim of the present study was to evaluate the effects caused by acute oral administration of AFB1 on behavioral tests and selected biochemical parameters. METHODS: Young male Wistar rats received a single administration of AFB1 (250 µg/kg/i.g.) and 48 hours thereafter they were subjected to behavioral analysis. After the tests, biochemical parameters were measured in the cerebral cortex. RESULTS: Acute treatment with AFB1 caused neurotoxic effects, evidenced by a significant reduction in the levels of non-enzymatic antioxidant defenses, ascorbic acid, and non-protein sulfhydryl groups. In addition, AFB1 increased protein kinase C (PKC) activation, evidenced by an increase in phosphorylation of Ser957 of PKCα. DISCUSSION: In this acute protocol, a single oral administration of AFB1 was able to cause changes in important neurochemical parameters, without concomitant, detectable behavioral alterations. These results reinforce that monitoring mycotoxin levels in food is essential to guarantee food security.

Effects of repeated fumonisin B1 exposure on markers of oxidative stress in liver, kidneys, and lungs of C57BL/6 mice.

Fu monisin B1 (FB1) is a mycotoxin commonly found in maize and maize-based products. Ingestion of FB1-contaminated causes a myriad of dose- and species-dependent toxic effects to human and animal health. In the present study we evaluated the effects of FB1 (8 mg/kg, i.p. for 4 days) on body weight and oxidative stress parameters in the liver, kidney and lung of C57BL/6 male mice. No changes in the organ-to-body weight ratio, organ-to-adrenal gland weight ratio or organ-to-brain weight ratio were found. On the other hand, FB1 exposure increased NPSH levels in liver and lungs whereas decreased FRAP content in liver and kidneys. Levels of TBARS, ascorbic acid and NOx content were not altered by FB1. In summary, four days of FB1 exposure are sufficient to disrupt antioxidant defenses in liver, kidneys and lungs of C57BL/6 male mice without concomitant changes in organs weight.

EP2 receptor agonist ONO-AE1-259-01 attenuates pentylenetetrazole- and pilocarpine-induced seizures but causes hippocampal neurotoxicity.

Epilepsy is a common and devastating neurological disease affecting more than 50 million people worldwide. Accumulating experimental and clinical evidence suggests that inflammatory pathways contribute to the development of seizures in various forms of epilepsy. In this context, while the activation of the PGE2 EP2 receptor causes early neuroprotective and late neurotoxic effects, the role of EP2 receptor in seizures remains unclear. We investigated whether the systemic administration of the highly selective EP2 agonist ONO-AE1-259-01 prevented acute pentylenetetrazole (PTZ)- and pilocarpine-induced seizures. The effect of ONO-AE1-259-01 on cell death in the hippocampal formation of adult male mice seven days after pilocarpine-induced status epilepticus (SE) was also evaluated. ONO-AE1-259-01 (10µg/kg, s.c.) attenuated PTZ- and pilocarpine-induced seizures, evidenced by the increased latency to seizures, decreased number and duration of seizures episodes and decreased mean amplitude of electrographic seizures. ONO-AE1-259-01 and pilocarpine alone significantly increased the number of pyknotic cells per se in all hippocampal subfields. The EP2 agonist also additively increased pilocarpine-induced pyknosis in the pyramidal cell layer of CA1 but reduced pilocarpine-induced pyknosis in the granule cell layer of the dentate gyrus (DG). Although the systemic administration of ONO-AE1-259-01 caused a significant anticonvulsant effect in our assays, this EP2 agonist caused extensive cell death. These findings limit the likelihood of EP2 receptor agonists being considered as novel potential anticonvulsant drugs.

The role of kinin B1 receptor and the effect of angiotensin I-converting enzyme inhibition on acute gout attacks in rodents.

OBJECTIVE: Verify the role of the kinin B1 receptors (B1R) and the effect of ACE inhibitors (ACEi) on acute gout induced by monosodium urate (MSU) crystals in rodents. METHODS: Painful (overt pain and allodynia) and inflammatory parameters (joint oedema, leukocyte trafficking, interleukin-1ß levels) of acute gout attacks were assessed several hours after an intra-articular injection of MSU (1.25 or 0.5 mg/articulation) into the ankle of rats or mice, respectively. The role of B1R was investigated using pharmacological antagonism or gene deletion. Additionally, B1R immunoreactivity in ankle tissue and sensory neurons, kininase I activity and des-Arg(9)-bradykinin synovial levels were also measured. Similar tools were used to investigate the effects of ACEi on a low dose of MSU (0.0125 mg/articulation)-induced inflammation. RESULTS: Kinin B1R antagonism or gene deletion largely reduced all painful and inflammatory signs of gout. Furthermore, MSU increased B1R expression in articular tissues, the content of the B1 agonist des-Arg(9)-bradykinin and the activity of the B1 agonist-forming enzyme kininase I. A low dose of MSU crystals, which did not induce inflammation in control animals, caused signs of acute gout attacks in ACEi-treated animals that were B1R-dependent. CONCLUSIONS: Kinin B1R contributes to acute gouty attacks, including the ones facilitated by ACEi. Therefore, B1R is a potential therapeutic target for the treatment and prophylaxis of gout, especially in patients taking ACEi.

Intrahippocampal infusion of spermidine improves memory persistence: Involvement of protein kinase A.

Spermidine (SPD) is an endogenous aliphatic amine that modulates GluN2B-containing NMDA receptors and improves memory. Recent evidence suggests that systemic SPD improves the persistence of the long term memory of fear. However, the role of hippocampal polyamines and its binding sites in the persistence of fear memory is to be determined, as well as its putative underlying mechanisms. This study investigated whether the intrahippocampal (i.h.) infusion of spermidine or arcaine, modulators of polyamine binding site at GluN2B-containing NMDA receptors, alters the persistence of the memory of contextual fear conditioning task in rats. We also investigated whether protein synthesis and cAMP dependent protein kinase (PKA) play a role in SPD-induced improvement of the fear memory persistence. While 12h post-training infusion of spermidine facilitated, arcaine and the inhibitor of protein synthesis (anisomycin) impaired the memory of fear assessed 7days after training. The infusion of arcaine, anisomycin or a selective PKA inhibitor (H-89), at doses that have no effect on memory per se, prevented the SPD-induced improvement of memory persistence. H-89 prevented the stimulatory effect of SPD on phospho-PKA/total-PKA ratio. These results suggests that the improvement of fear memory persistence induced by spermidine involves GluN2B-containing NMDA receptors, PKA pathway and protein synthesis in rats.

A neuronal disruption in redox homeostasis elicited by ammonia alters the glycine/glutamate (GABA) cycle and contributes to MMA-induced excitability.

Hyperammonemia is a common finding in children with methylmalonic acidemia. However, its contribution to methylmalonate-induced excitotoxicty is poorly understood. The aim of this study was to evaluate the mechanisms by which ammonia influences in the neurotoxicity induced by methylmalonate (MMA) in mice. The effects of ammonium chloride (NH4Cl 3, 6, and 12 mmol/kg; s.c.) on electroencephalographic (EEG) and behavioral convulsions induced by MMA (0.3, 0.66, and 1 µmol/2 µL, i.c.v.) were observed in mice. After, ammonia, TNF-α, IL1ß, IL-6, nitrite/nitrate (NOx) levels, mitochondrial potential (ΔΨ), reactive oxygen species (ROS) generation, Methyl-Tetrazolium (MTT) reduction, succinate dehydrogenase (SDH), and Na(+), K(+)-ATPase activity levels were measured in the cerebral cortex. The binding of [(3)H]flunitrazepam, release of glutamate-GABA; glutamate decarboxylase (GAD) and glutamine synthetase (GS) activity and neuronal damage [opening of blood brain barrier (BBB) permeability and cellular death volume] were also measured. EEG recordings showed that an intermediate dose of NH4Cl (6 mmol/kg) increased the duration of convulsive episodes induced by MMA (0.66 µmol/2 µL i.c.v). NH4Cl (6 mmol/kg) administration also induced neuronal ammonia and NOx increase, as well as mitochondrial ROS generation throughout oxidation of 2,7-dichlorofluorescein diacetate (DCFH-DA) to DCF-RS, followed by GS and GAD inhibition. The NH4Cl plus MMA administration did not alter cytokine levels, plasma fluorescein extravasation, or neuronal damage. However, it potentiated DCF-RS levels, decreased the ΔΨ potential, reduced MTT, inhibited SDH activity, and increased Na(+), K(+)-ATPase activity. NH4Cl also altered the GABA cycle characterized by GS and GAD activity inhibition, [(3)H]flunitrazepam binding, and GABA release after MMA injection. On the basis of our findings, the changes in ROS and reactive nitrogen species (RNS) levels elicited by ammonia alter the glycine/glutamate (GABA) cycle and contribute to MMA-induced excitability.

Increased susceptibility to pentylenetetrazol following survival of cerebral malaria in mice.

Malaria is considered a neglected disease and public health problem, affecting >200 million people worldwide. In the present study we used the Plasmodium berghei ANKA (PbA) model of experimental cerebral malaria (CM) in C57BL/6 mice. After rescue from CM and parasite clearance, animals were submitted to a seizure susceptibility test (45 days after infection) using a low dose of pentylenetetrazol (PTZ, 30 mg/kg) and monitored with use of behavioral and electroencephalography (EEG) methods. Mice rescued from CM presented a reduced latency to myoclonic and tonic-clonic seizures and an increased duration of tonic-clonic seizures. In addition, quantitative analysis of EEG revealed a decrease in relative power at beta frequency band in PbA-infected animals after PTZ injection. Our results suggest that CM may lead to increased susceptibility to seizures in mice.

Rosmarinic acid is anticonvulsant against seizures induced by pentylenetetrazol and pilocarpine in mice.

Epilepsy is a chronic neurological disease characterized by spontaneous recurrent seizures (SRS). Current anticonvulsant drugs are ineffective in nearly one-third of patients and may cause significant adverse effects. Rosmarinic acid is a naturally occurring substance which displays several biological effects including antioxidant and neuroprotective activity. Since oxidative stress and excitotoxicity play a role in the pathophysiology of seizures, we aimed the present study to test the hypothesis that rosmarinic acid displays anticonvulsant and disease-modifying effects. Female C57BL/6 mice received rosmarinic acid (0, 3, 10, or 30mg/kg; p.o.) 60min before the injection of pentylenetetrazol (PTZ, 60mg/kg; i.p.) or pilocarpine (300mg/kg, i.p.). Myoclonic and generalized tonic-clonic seizure latencies and generalized seizure duration were analyzed by behavioral and electroencephalographic (EEG) methods. The effect of acute administration of rosmarinic acid on mice behavior in the open-field, object recognition, rotarod, and forced swim tests was also evaluated. In an independent set of experiments, we evaluated the effect of rosmarinic acid (3 or 30mg/kg, p.o. for 14days) on the development of SRS and behavioral comorbidities in the pilocarpine post-status epilepticus (SE) model of epilepsy. Rosmarinic acid dose-dependently (peak effect at 30mg/kg) increased the latency to myoclonic jerks and generalized seizures in the PTZ model and increased the latency to myoclonic jerks induced by pilocarpine. Rosmarinic acid (30mg/kg) increased the number of crossings, the time at the center of the open field, and the immobility time in the forced swim test. In the chronic epilepsy model, treatment with rosmarinic acid did not prevent the appearance of SRS or behavioral comorbidities. In summary, rosmarinic acid displayed acute anticonvulsant-like activity against seizures induced by PTZ or pilocarpine in mice, but further studies are needed to determine its epilepsy-modifying potential.

Anticonvulsant activity of ß-caryophyllene against pentylenetetrazol-induced seizures.

Increasing evidence suggests that plant-derived extracts and their isolated components are useful for treatment of seizures and, hence, constitute a valuable source of new antiepileptic drugs with improved efficacy and better adverse effect profile. ß-Caryophyllene is a natural bicyclic sesquiterpene that occurs in a wide range of plant species and displays a number of biological actions, including neuroprotective activity. In the present study, we tested the hypothesis that ß-caryophyllene displays anticonvulsant effects. In addition, we investigated the effect of ß-caryophyllene on behavioral parameters and on seizure-induced oxidative stress. Adult C57BL/6 mice received increasing doses of ß-caryophyllene (0, 10, 30, or 100mg/kg). After 60 min, we measured the latencies to myoclonic and generalized seizures induced by pentylenetetrazole (PTZ, 60 mg/kg). We found that ß-caryophyllene increased the latency to myoclonic jerks induced by PTZ. This result was confirmed by electroencephalographic analysis. In a separate set of experiments, we found that mice treated with an anticonvulsant dose of ß-caryophyllene (100mg/kg) displayed an improved recognition index in the object recognition test. This effect was not accompanied by behavioral changes in the open-field, rotarod, or forced swim tests. Administration of an anticonvulsant dose of ß-caryophyllene (100mg/kg) did not prevent PTZ-induced oxidative stress (i.e., increase in the levels of thiobarbituric acid-reactive substances or the decrease in nonprotein thiols content). Altogether, the present data suggest that ß-caryophyllene displays anticonvulsant activity against seizures induced by PTZ in mice. Since no adverse effects were observed in the same dose range of the anticonvulsant effect, ß-caryophyllene should be further evaluated in future development of new anticonvulsant drugs.

Autonomic cardiocirculatory control in mice with reduced expression of the vesicular acetylcholine transporter.

In cardiovascular diseases, sympathetic tone has been comprehensively studied, whereas parasympathetic tone has received minor attention. The vesicular ACh transporter (VAChT) knockdown homozygous (VAChT KD(HOM)) mouse is a useful model for examining the cardiocirculatory sympathovagal balance. Therefore, we investigated whether cholinergic dysfunction caused by reduced VAChT expression could adversely impact hemodynamic parameter [arterial pressure (AP) and heart rate (HR)] daily oscillation, baroreflex sensitivity, hemodynamic variability, sympathovagal balance, and cardiovascular reactivity to restraint stress. Wild-type and VAChT KD(HOM) mice were anesthetized for telemetry transmitter implantation, and APs and HRs were recorded 10 days after surgical recovery. Changes in HR elicited by methylatropine and propranolol provided the indexes of sympathovagal tone. Cardiovascular reactivity in response to a restraint test was examined 24 h after continuous recordings of AP and HR. VAChT KD(HOM) mice exhibited reduced parasympathetic and elevated sympathetic tone. Daily oscillations of AP and HR as well as AP variability were similar between groups. Nevertheless, HR variability, patterns with two dissimilar variations from symbolic analysis, and baroreflex sensitivity were reduced in VAChT KD(HOM) mice. The change in mean AP due to restraint stress was greater in VAChT KD(HOM) mice, whereas the tachycardic response was not. These findings demonstrate that the cholinergic dysfunction present in the VAChT KD(HOM) mouse did not adversely impact basal hemodynamic parameters but promoted autonomic imbalance, an attenuation of baroreflex sensitivity, and a greater pressure response to restraint stress. These results provide a framework for understanding how autonomic imbalance impacts cardiovascular function.

A novel cytosporone 3-Heptyl-4,6-dihydroxy-3H-isobenzofuran-1-one: synthesis; toxicological, apoptotic and immunomodulatory properties; and potentiation of mutagenic damage.

BACKGROUND: A large number of studies are attempting to identify alternative products from natural sources or synthesized compounds that effectively interact with cancer cells without causing adverse effects on healthy cells. Resorcinolic lipids are a class of bioactive compounds that possess anticancer activity and are able to interact with the lipid bilayer. Therefore, the objective of this study was to synthesize a novel resorcinolic lipid and test its biological proprieties. METHODS: We aimed to synthesize a novel resorcinolic lipid belonging to the class of cytosporones, AMS049 (3-Heptyl-4,6-dihydroxy-3H-isobenzofuran-1-one) and to evaluate the toxicity of two concentrations of this lipid (7.5 and 10 mg/kg) by determining its genotoxic, mutagenic, immunomodulatory, and apoptotic effects, as well as any biochemical and histopathological alterations in mice treated with cyclophosphamide. The results were analyzed by ANOVA followed by the Tukey test A . level of significance of p < 0.05 was adopted. RESULTS: The new cytosporone AMS049 was synthesized in only three steps and in satisfactory yields. The results indicate that the compound is neither genotoxic nor mutagenic and does not alter biochemical parameters. The histological alterations observed in the liver and kidneys did not compromise the function of these organs. Histology of the spleen suggested immunomodulation, although no changes were observed in splenic phagocytosis or differential blood cell count. The results also show that AMS049 potentiates the mutagenic effect of the chemotherapy drug cyclophosphamide and that the combination induces apoptosis. CONCLUSION: These facts indicate a potential therapeutic application of this novel cytosporone as an important chemotherapeutic adjuvant.

Heart rate complexity in sinoaortic-denervated mice.

NEW FINDINGS: What is the central question of this study? New measurements for cardiovascular complexity, such as detrended fluctuation analysis (DFA) and multiscale entropy (MSE), have been shown to predict cardiovascular outcomes. Given that cardiovascular diseases are accompanied by autonomic imbalance and decreased baroreflex sensitivity, the central question is: do baroreceptors contribute to cardiovascular complexity? What is the main finding and its importance? Sinoaortic denervation altered both DFA scaling exponents and MSE, indicating that both short- and long-term mechanisms of complexity are altered in sinoaortic denervated mice, resulting in a loss of physiological complexity. These results suggest that the baroreflex is a key element in the complex structures involved in heart rate variability regulation. Recently, heart rate (HR) oscillations have been recognized as complex behaviours derived from non-linear processes. Physiological complexity theory is based on the idea that healthy systems present high complexity, i.e. non-linear, fractal variability at multiple scales, with long-range correlations. The loss of complexity in heart rate variability (HRV) has been shown to predict adverse cardiovascular outcomes. Based on the idea that most cardiovascular diseases are accompanied by autonomic imbalance and a decrease in baroreflex sensitivity, we hypothesize that the baroreflex plays an important role in complex cardiovascular behaviour. Mice that had been subjected to sinoaortic denervation (SAD) were implanted with catheters in the femoral artery and jugular vein 5 days prior to the experiment. After recording the baseline arterial pressure (AP), pulse interval time series were generated from the intervals between consecutive values of diastolic pressure. The complexity of the HRV was determined using detrended fluctuation analysis and multiscale entropy. The detrended fluctuation analysis α1 scaling exponent (a short-term index) was remarkably decreased in the SAD mice (0.79 ± 0.06 versus 1.13 ± 0.04 for the control mice), whereas SAD slightly increased the α2 scaling exponent (a long-term index; 1.12 ± 0.03 versus 1.04 ± 0.02 for control mice). In the SAD mice, the total multiscale entropy was decreased (13.2 ± 1.3) compared with the control mice (18.9 ± 1.4). In conclusion, fractal and regularity structures of HRV are altered in SAD mice, affecting both short- and long-term mechanisms of complexity, suggesting that the baroreceptors play a considerable role in the complex structure of HRV.