Gastroprotective activity and physicochemical analysis of carboxymethylated gum from Anadenanthera colubrina.

Biotechnological advancements require the physicochemical alteration of molecules to enhance their biological efficacy for the effective treatment of gastric ulcers. The study aimed to produce a polyelectrolytic compound from red angico gum (AG) by carboxymethylation, evaluate its physicochemical characteristics and investigate gastric protection against ethanol-induced ulcers. AG and carboxymethylated angico gum (CAG) were characterized by Fourier transform infrared spectroscopy, determination of the degree of substitution and gel permeation chromatography (GPC) and 13C NMR techniques. The results demonstrated that the modification of the polymer was satisfactory, presenting conformational changes e improving the interaction with the gastric mucosa. AG and CAG reduced macroscopic and microscopic damage such as edema, hemorrhage and cell loss caused by exposure of the mucosa to alcohol. Both demonstrated antioxidant activity in vitro, and in vivo, pretreatment with gums led to the restoration of superoxide dismutase and glutathione levels compared to the injured group. Concurrently, the levels of malondialdehyde and nitrite decreased. Atomic force microscopy showed that CAG presented better conformational properties of affinity and protection with the gastric mucosa compared to AG in the acidic pH. Based on our findings, it is suggested that this compound holds promise as a prospective product for future biotechnological applications.

Neurochemical abnormalities in the hippocampus of male rats displaying audiogenic seizures, a genetic model of epilepsy.

BACKGROUND: Epilepsy is a disorder characterized by recurrent seizures that affects 1% of the population. However, the neurochemical alterations observed in epilepsy are not fully understood. There are different animal models of epilepsy, such as genetic or drug induced. In the present study, we utilize Wistar Audiogenic Rats (WAR), a murine strain that develops seizures in response to high intensity audio stimulation, in order to investigate abnormalities in glutamatergic and GABAergic systems. METHODS: Synaptosomes and glial plasmalemmal vesicles were prepared from hippocampus and cortex, respectively. Glutamate and GABA release and uptake were assayed by monitoring the fluorescence and using L-[3H]-radiolabeled compounds. Glutamate and calcium concentration in the synaptosomes were also measured. The expression of neuronal calcium sensor 1 (NCS-1) was determined by western blot. RESULTS: Glutamate and GABA release evoked by KCl was decreased in WAR compared to control Wistar rats. Calcium independent release was not considerably different in both groups. The total amount of glutamate of synaptosomes, as well as glutamate uptake by synaptosomes and GPV were also decreased in WAR in comparison with the controls. In addition, [Ca2+]i of hippocampal synaptosomes, as well as NCS-1 expression in the hippocampus, were increased in WAR in comparison with controls. CONCLUSION: In conclusion, our results suggest that WAR have important alterations in the glutamatergic and GABAergic pathways, as well as an increased expression of NCS-1 in the hippocampus and inferior colliculus. These alterations may be linked to the spreading of hyperexcitability and recruitment of various brain regions.

High-refined carbohydrate diet consumption induces neuroinflammation and anxiety-like behavior in mice.

Consumption of poor nutrients diets is associated with fat tissue expansion and with a central and peripheral low-grade inflammation. In this sense, the microglial cells in the central nervous system are activated and release pro-inflammatory cytokines that up-regulate the inducible nitric oxide synthase (iNOS), promoting Nitric Oxide (NO) production. The excess of NO has been proposed to facilitate anxious states in humans and rodents. We evaluated whether consumption of a high-refined carbohydrate-containing diet (HC) in mice induced anxiety-like behavior in the Novelty Suppressed Feeding Test (NFST) trough facilitation of NO, in the prefrontal cortex (PFC) and hippocampus (HIP). We also verified if HC diet induces activation of microglial cells, alterations in cytokine and leptin levels in such regions. Male BALB/c mice received a standard diet or a HC diet for 3 days or 12 weeks. The chronic consumption of HC diet, but not acute, induced an anxiogenic-like effect in the NSF test and an increase in the nitrite levels in the PFC and HIP. The preferential iNOS inhibitor, aminoguanidine (50 mg/kg, i.p.), attenuated such effects. Moreover, microglial cells in the HIP and PFC were activated after chronic consumption of HC diet. Finally, the expression of iNOS in the PFC and TNF, IL6 and leptin levels in HIP were higher in chronically HC fed mice. Taken together, our data reinforce the notion that diets containing high-refined carbohydrate facilitate anxiety-like behavior, mainly after a long period of consumption. The mechanisms involve, at least in part, the augmentation of neuroinflammatory processes in brain areas responsible for anxiety control.

New multifunctional AChE inhibitor drug prototypes protect against Aß-induced memory deficit.

Alzheimer's disease (AD) is the most incident neurodegenerative disorder, characterized by accumulation of extracellular amyloid-ß (Aß), intracellular neurofibrillary tangles, and cognitive impairment. The current available treatments are mainly based on the use of reversible acetylcholinesterase (AChE) inhibitors, which only ameliorate the cognitive deficits. However, it is important to develop disease-modifying drugs with neuroprotective effects in order to hamper the progression of the disease. Here, we describe the effect of four promising new drugs with additional protective characteristics on AD-associated memory changes. C57Bl/6 mice treated with the compounds received an intra-hippocampal injection of Aß1-40 and were submitted to the novel object recognition test, to evaluate memory recovery. All the compounds prevented memory loss. Compounds PQM-56 (4c) and PQM-67 (4g) showed the best profile of memory recovery, representing potential drug candidates for AD treatment.

URB597 ameliorates the deleterious effects induced by binge alcohol consumption in adolescent rats.

Heavy episodic drinking or binge drinking during adolescence may elicit serious neurotoxic consequences in cerebral areas (e.g., the prefrontal cortex, i.e., PFC) and the hippocampus, delay the maturation of the brain and increase the probability of drug abuse and dependence. The endocannabinoid system plays an important role in neuroprotection by reducing oxidative stress and neuroinflammation. In the present study, we aimed to investigate whether URB597, an inhibitor of the metabolic enzyme of the endocannabinoid anandamide (AEA), altered the effects of acute and chronic alcohol administration beginning during rat adolescence on recognition memory, neuroinflammation and brain-derived neurotrophic factor (BDNF) levels. The animals received intraperitoneal injections of URB597 (0.3 mg/Kg) or vehicle followed by the oral administration of ethanol (3 or 6 g/Kg) or distilled water for 3 consecutive days in one week (acute binging) or over 4 weeks (chronic binging). The groups were submitted to the novel object recognition task, and their PFCs and hippocampi were removed for analyses of the cytokine and BDNF levels. URB597 potentiated long-term memory after the 3 mg/Kg acute alcohol administration. The chronic binge alcohol administration increased the interferon (IFN)-γ and tumor necrosis factor (TNF)-α levels in the PFC and hippocampus and the interleukin (IL)-10 and BDNF levels in the PFC, and these effects were prevented by URB597. Our results indicate that the neuromodulation facilitated by AEA can reduce the neuroimmune response induced by the chronic administration of alcohol beginning in adolescence in rats.

In-depth characterization of congenital Zika syndrome in immunocompetent mice: Antibody-dependent enhancement and an antiviral peptide therapy.

BACKGROUND: Zika virus (ZIKV) infection during pregnancy may cause major congenital defects, including microcephaly, ocular, articular and muscle abnormalities, which are collectively defined as Congenital Zika Syndrome. Here, we performed an in-depth characterization of the effects of congenital ZIKV infection (CZI) in immunocompetent mice. METHODS: Pregnant dams were inoculated with ZIKV on embryonic day 5.5 in the presence or absence of a sub-neutralizing dose of a pan-flavivirus monoclonal antibody (4G2) to evaluate the potential role of antibody-dependent enhancement phenomenon (ADE) during short and long outcomes of CZI. FINDINGS: ZIKV infection induced maternal immune activation (MIA), which was associated with occurrence of foetal abnormalities and death. Therapeutic administration of AH-D antiviral peptide during the early stages of pregnancy prevented ZIKV replication and death of offspring. In the post-natal period, CZI was associated with a decrease in whole brain volume, ophthalmologic abnormalities, changes in testicular morphology, and disruption in bone microarchitecture. Some alterations were enhanced in the presence of 4G2 antibody. INTERPRETATION: Our results reveal that early maternal ZIKV infection causes several birth defects in immunocompetent mice, which can be potentiated by ADE phenomenon and are associated with MIA. Additionally, antiviral treatment with AH-D peptide may be beneficial during early maternal ZIKV infection. FUND: This work was supported by the Brazilian National Science Council (CNPq, Brazil), Minas Gerais Foundation for Science (FAPEMIG), Funding Authority for Studies and Projects (FINEP), Coordination of Superior Level Staff Improvement (CAPES), National Research Foundation of Singapore and Centre for Precision Biology at Nanyang Technological University.

Glial Cell-Elicited Activation of Brain Microvasculature in Response to Brucella abortus Infection Requires ASC Inflammasome-Dependent IL-1ß Production.

Blood-brain barrier activation and/or dysfunction are a common feature of human neurobrucellosis, but the underlying pathogenic mechanisms are largely unknown. In this article, we describe an immune mechanism for inflammatory activation of human brain microvascular endothelial cells (HBMEC) in response to infection with Brucella abortus Infection of HBMEC with B. abortus induced the secretion of IL-6, IL-8, and MCP-1, and the upregulation of CD54 (ICAM-1), consistent with a state of activation. Culture supernatants (CS) from glial cells (astrocytes and microglia) infected with B. abortus also induced activation of HBMEC, but to a greater extent. Although B. abortus-infected glial cells secreted IL-1ß and TNF-α, activation of HBMEC was dependent on IL-1ß because CS from B. abortus-infected astrocytes and microglia deficient in caspase-1 and apoptosis-associated speck-like protein containing a CARD failed to induce HBMEC activation. Consistently, treatment of CS with neutralizing anti-IL-1ß inhibited HBMEC activation. Both absent in melanoma 2 and Nod-like receptor containing a pyrin domain 3 are partially required for caspase-1 activation and IL-1ß secretion, suggesting that multiple apoptosis-associated speck-like protein containing CARD-dependent inflammasomes contribute to IL-1ß-induced activation of the brain microvasculature. Inflammasome-mediated IL-1ß secretion in glial cells depends on TLR2 and MyD88 adapter-like/TIRAP. Finally, neutrophil and monocyte migration across HBMEC monolayers was increased by CS from Brucella-infected glial cells in an IL-1ß-dependent fashion, and the infiltration of neutrophils into the brain parenchyma upon intracranial injection of B. abortus was diminished in the absence of Nod-like receptor containing a pyrin domain 3 and absent in melanoma 2. Our results indicate that innate immunity of the CNS set in motion by B. abortus contributes to the activation of the blood-brain barrier in neurobrucellosis and IL-1ß mediates this phenomenon.

Inhibition of Neuroinflammation in LPS-Activated Microglia by Cryptolepine.

Cryptolepine, an indoloquinoline alkaloid in Cryptolepis sanguinolenta, has anti-inflammatory property. In this study, we aimed to evaluate the effects of cryptolepine on lipopolysaccharide (LPS)- induced neuroinflammation in rat microglia and its potential mechanisms. Microglial activation was induced by stimulation with LPS, and the effects of cryptolepine pretreatment on microglial activation and production of proinflammatory mediators, PGE2/COX-2, microsomal prostaglandin E2 synthase and nitric oxide/iNOS were investigated. We further elucidated the role of Nuclear Factor-kappa B (NF- κ B) and the mitogen-activated protein kinases in the antiinflammatory actions of cryptolepine in LPS-stimulated microglia. Our results showed that cryptolepine significantly inhibited LPS-induced production of tumour necrosis factor-alpha (TNF α ), interleukin-6 (IL-6), interleukin-1beta (IL-1 ß ), nitric oxide, and PGE2. Protein and mRNA levels of COX-2 and iNOS were also attenuated by cryptolepine. Further experiments on intracellular signalling mechanisms show that I κ B-independent inhibition of NF- κ B nuclear translocation contributes to the anti-neuroinflammatory actions of cryptolepine. Results also show that cryptolepine inhibited LPS-induced p38 and MAPKAPK2 phosphorylation in the microglia. Cell viability experiments revealed that cryptolepine (2.5 and 5 µ M) did not produce cytotoxicity in microglia. Taken together, our results suggest that cryptolepine inhibits LPS-induced microglial inflammation by partial targeting of NF- κ B signalling and attenuation of p38/MAPKAPK2.

Anti-neuroinflammatory properties of synthetic cryptolepine in human neuroblastoma cells: possible involvement of NF-κB and p38 MAPK inhibition.

Cryptolepis sanguinolenta and its bioactive alkaloid, cryptolepine have shown anti-inflammatory activity. However, the underlying mechanism of anti-inflammatory action in neuronal cells has not been investigated. In the present study we evaluated an extract of C. sanguinolenta (CSE) and cryptolepine (CAS) on neuroinflammation induced with IL-1ß in SK-N-SH neuroblastoma cells. We then attempted to elucidate the mechanisms underlying the anti-neuroinflammatory effects of CAS in SK-N-SH cells. Cells were stimulated with 10 U/ml of IL-1ß in the presence or absence of different concentrations of CSE (25-200 µg/ml) and CAS (2.5-20 µM). After 24 h incubation, culture media were collected to measure the production of PGE2 and the pro-inflammatory cytokines (TNFα and IL-6). Protein and gene expressions of cyclooxygenase (COX-2) and microsomal prostaglandin synthase-1 (mPGES-1) were studied by immunoblotting and qPCR, respectively. CSE produced significant (p < 0.05) inhibition of TNFα, IL-6 and PGE2 production in SK-N-SH cells. Studies on CAS showed significant and dose-dependent inhibition of TNFα, IL-6 and PGE2 production in IL-1ß-stimulated cells without affecting viability. Pre-treatment with CAS (10 and 20 µM) was also found to inhibit IL-1ß-induced protein and gene expressions of COX-2 and mPGES-1. Further studies to determine the mechanism of action of CAS showed inhibition of NF-κBp65 nuclear translocation, but not IκB phosphorylation. At 10 and 20 µM, CAS inhibited IL-1ß-induced phosphorylation of p38 MAPK. Studies on the downstream substrate of p38, MAPK-activated protein kinase 2 (MAPKAPK2) showed that CAS produced significant (p < 0.05) and dose dependent inhibition of MAPKAPK2 phosphorylation in IL-1ß-stimulated SK-N-SH cells. This study clearly shows that cryptolepine (CAS) inhibits neuroinflammation through mechanisms involving inhibition of COX-2 and mPGES-1. It is suggested that these actions are probably mediated through NF-κB and p38 signalling.

Pharmacological inhibition of Akt and downstream pathways modulates the expression of COX-2 and mPGES-1 in activated microglia.

BACKGROUND: Microglia are considered a major target for modulating neuroinflammatory and neurodegenerative disease processes. Upon activation, microglia secrete inflammatory mediators that contribute to the resolution or to further enhancement of damage in the central nervous system (CNS). Therefore, it is important to study the intracellular pathways that are involved in the expression of the inflammatory mediators. Particularly, the role of the phosphatidylinositol 3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR) and glycogen synthase kinase-3 (GSK-3) pathways in activated microglia is unclear. Thus, in the present study we investigated the role of Akt and its downstream pathways, GSK-3 and mTOR, in lipopolysaccharide (LPS)-activated primary rat microglia by pharmacological inhibition of these pathways in regard to the expression of cyclooxygenase (COX)-2 and microsomal prostaglandin E synthase-1 (mPGES-1) and to the production of prostaglandin (PG) E2 and PGD2. FINDINGS: We show that inhibition of Akt by the Akt inhibitor X enhanced the production of PGE2 and PGD2 without affecting the expression of COX-2, mPGES-1, mPGES-2 and cytosolic prostaglandin E synthase (cPGES). Moreover, inhibition of GSK-3 reduced the expression of both COX-2 and mPGES-1. In contrast, the mTOR inhibitor rapamycin enhanced both COX-2 and mPGES-1 immunoreactivity and the release of PGE2 and PGD2. Interestingly, NVP-BEZ235, a dual PI3K/mTOR inhibitor, enhanced COX-2 and reduced mPGES-1 immunoreactivity, albeit PGE2 and PGD2 levels were enhanced in LPS-stimulated microglia. However, this compound also increased PGE2 in non-stimulated microglia. CONCLUSION: Taken together, we demonstrate that blockade of mTOR and/or PI3K/Akt enhances prostanoid production and that PI3K/Akt, GSK-3 and mTOR differently regulate the expression of mPGES-1 and COX-2 in activated primary microglia. Therefore, these pathways are potential targets for the development of novel strategies to modulate neuroinflammation.

Tetracyclines and pain.

Tetracyclines are natural or semi-synthetic bacteriostatic agents which have been used since late 1940s against a wide range of gram-positive and gram-negative bacteria and atypical organisms such as chlamydia, mycoplasmas, rickettsia, and protozoan parasites. After the discovery of the first tetracyclines, a second generation of compounds was sought in order to improve water solubility for parenteral administration or to enhance bioavailability after oral administration. This approach resulted in the development of doxycycline and minocycline in the 1970s. Doxycycline was included in the World Health Organization Model List of Essential Medicines either as antibacterial or to prevent malaria or to treat patients with this disease. Additional development led to the third generation of tetracyclines, being tigecycline the only medicine of this class to date. Besides antibacterial activities, the anti-inflammatory, antihypernociceptive and neuroprotective activities of tetracyclines began to be widely studied in the late 1990s. Indeed, there has been an increasing interest in investigating the effects induced by minocycline as this liposoluble derivative is known to cross the blood-brain barrier to the greatest extent. Minocycline induces antihypernociceptive effects in a wide range of animal models of nociceptive, inflammatory and neuropathic pain. In this study, we discuss the antihypernociceptive activity of tetracyclines and summarise its underlying cellular and molecular mechanisms.

Norepinephrine enhances the LPS-induced expression of COX-2 and secretion of PGE2 in primary rat microglia.

BACKGROUND: Recent studies suggest an important role for neurotransmitters as modulators of inflammation. Neuroinflammatory mediators such as cytokines and molecules of the arachidonic acid pathway are generated and released by microglia. The monoamine norepinephrine reduces the production of cytokines by activated microglia in vitro. However, little is known about the effects of norepinephrine on prostanoid synthesis. In the present study, we investigate the role of norepinephrine on cyclooxygenase- (COX-)2 expression/synthesis and prostaglandin (PG)E2 production in rat primary microglia. RESULTS: Interestingly, norepinephrine increased COX-2 mRNA, but not protein expression. Norepinephrine strongly enhanced COX-2 expression and PGE2 production induced by lipopolysaccharide (LPS). This effect is likely to be mediated by beta-adrenoreceptors, since beta-, but not alpha-adrenoreceptor agonists produced similar results. Furthermore, beta-adrenoreceptor antagonists blocked the enhancement of COX-2 levels induced by norepinephrine and beta-adrenoreceptor agonists. CONCLUSIONS: Considering that PGE2 displays different roles in neuroinflammatory and neurodegenerative disorders, norepinephrine may play an important function in the modulation of these processes in pathophysiological conditions.

Opposite effects of anandamide and N-arachidonoyl dopamine in the regulation of prostaglandin E and 8-iso-PGF formation in primary glial cells.

It is widely accepted that neuroinflammation is a key player in various pathological events associated with brain injury. More specifically, glial activation and the subsequent release of pro-inflammatory cytokines, reactive oxygen species (ROS), and prostaglandins play a role of paramount importance in cerebral damage. In this study, we examined the role of two endocannabinoids, anandamide (AEA) and N-arachidonoyldopamine (NADA) in the regulation of prostaglandin E(2) (PGE(2)) synthesis in primary glial cells. We show that NADA is a potent inhibitor of PGE(2) synthesis in lipopolysaccharide (LPS) stimulated cells, without modifying the expression or enzymatic activity of COX-2 and the production of prostaglandin D(2). We also show that NADA has the ability to prevent the free radical formation in primary microglial cells. The key findings of this investigation are our observation that AEA and NADA have opposite effects on glial cells and, most importantly, the first description of NADA as a potential antioxidative and anti-inflammatory agent acting through a mechanism that involves reduction in the synthesis of microsomal prostaglandin E synthase in LPS-activated microglia. These findings provide new mechanistic insights into the anti-inflammatory activities of NADA in the CNS and its potential to design novel therapeutic strategies to manage neuroinflammatory diseases.

Penfigoide bolhoso: uma manifestaçao paraneoplasica do cancer de esofago? / Bullous pemphigoid: a para neophasic manifestation of edophageal cancer

E relatado um caso de penfigo bolhoso (PB) associado a carcinoma epidermoide de esofago (CEE). O diagnostico de PB foi elaborado atraves de biopsia e imunofluorescencia direta da pele, enquanto o diagnostico de CCE foi firmado pela endoscopia digestiva e biopsia. A evoluçao da dermatose esteve intimamente relacionada ao tratamento do tumor esofagico (cirurgia e radioterapia), mas a revisao da literatura nao estabelece claramente a relaçao de interdependencia das patologias

Esfincterotomia lateral interna: 53 casos / Lateral internal sphincterotomy: 53 cases

Os autores relatam sua experiência cirúrgica e o acompanhamento de 53 pacientes operados pela técnica de esfincterotomia lateral interna subcutânea fechada. Do total, 41 eram do sexo feminino e 12 do sexo masculino, sendo que a idade variou de 19 a 73 anos. A técnica utilizada consistiu na secçäo parcial do músculo esfíncter interno, e os resultados basearam-se no tempo de desaparecimento dos sinais e sintomas, bem cocmo no de cicatrizaçiao da fissura. Tecem também comentários sobre o quadro clínico e incidência da patologia, relacionando-as aos pacientes examinados e tratados na presente casuística