TNF-α blockage prevents late neurological consequences of Zika virus infection in mice.

Zika virus (ZIKV) is a neurotropic Orthoflavivirus that causes a myriad of neurological manifestations in newborns exposed in uterus. Despite the devastating consequences of ZIKV on the developing brain, strategies to prevent or treat the consequences of viral infection are not yet available. We previously showed that short-term treatment with the TNF-α neutralizing monoclonal antibody. Infliximab could prevent seizures at acute and chronic stages of ZIKV infection, but had no impact on long-term cognitive and motor dysfunction. Due to the central role of inflammation in ZIKV-neuropathology, we hypothesized that prolonged treatment with the anti-TNF-α monoclonal antibody Infliximab could provide complete rescue of long-term behavioral deficits associated with neonatal ZIKV infection in mice. Here, neonatal (post-natal day 3) Swiss mice were submitted to subcutaneous (s.c.) injection of 106 PFU of ZIKV or mock medium and were then treated with Infliximab (20 µg/day) or sterile saline intraperitoneally (i.p.), for 40 days starting on the day of infection, and behavioral assessment started at 60 days post-infection (dpi). Infliximab prevented ZIKV-induced cognitive and motor impairments in mice. In addition, microgliosis and cell death found in mice following ZIKV infection were partially reversed by TNF-α blockage. Altogether, these results suggest that TNF-α-mediated inflammation is central for late ZIKV-induced behavioral deficits and cell death and strategies targeting this cytokine may be promising approaches to treat subjects exposed to the virus during development.

Zika virus infection impairs synaptogenesis, induces neuroinflammation, and could be an environmental risk factor for autism spectrum disorder outcome.

Zika virus (ZIKV) infection was first associated with Central Nervous System (CNS) infections in Brazil in 2015, correlated with an increased number of newborns with microcephaly, which ended up characterizing the Congenital Zika Syndrome (CZS). Here, we investigated the impact of ZIKV infection on the functionality of iPSC-derived astrocytes. Besides, we extrapolated our findings to a Brazilian cohort of 136 CZS children and validated our results using a mouse model. Interestingly, ZIKV infection in neuroprogenitor cells compromises cell migration and causes apoptosis but does not interfere in astrocyte generation. Moreover, infected astrocytes lost their ability to uptake glutamate while expressing more glutamate transporters and secreted higher levels of IL-6. Besides, infected astrocytes secreted factors that impaired neuronal synaptogenesis. Since these biological endophenotypes were already related to Autism Spectrum Disorder (ASD), we extrapolated these results to a cohort of children, now 6-7 years old, and found seven children with ASD diagnosis (5.14 %). Additionally, mice infected by ZIKV revealed autistic-like behaviors, with a significant increase of IL-6 mRNA levels in the brain. Considering these evidence, we inferred that ZIKV infection during pregnancy might lead to synaptogenesis impairment and neuroinflammation, which could increase the risk for ASD.

Mitotherapy prevents peripheral neuropathy induced by oxaliplatin in mice.

Oxaliplatin (OXA) is an antineoplastic agent used for the treatment of cisplatin-resistant tumours, presenting lower incidence of nephrotoxicity and myelotoxicity than other platinum-based drugs. However, OXA treatment is highly associated with painful peripheral neuropathy, a well-known and relevant side effect caused by mitochondrial dysfunction. The transfer of functional exogenous mitochondria (mitotherapy) is a promising therapeutic strategy for mitochondrial diseases. We investigated the effect of mitotherapy on oxaliplatin-induced painful peripheral neuropathy (OIPN) in male mice. OIPN was induced by i.p. injections of oxaliplatin (3 mg/kg) over 5 consecutive days. Mechanical (von Frey test) and cold (acetone drop test) allodynia were evaluated between 7 and 17 days after the first OXA treatment. Mitochondria was isolated from donor mouse livers and mitochondrial oxidative phosphorylation was assessed with high resolution respirometry. After confirming that the isolated mitochondria were functional, the organelles were administered at the dose of 0.5 mg/kg of mitochondrial protein on days 1, 3 and 5. Treatment with OXA caused both mechanical and cold allodynia in mice that were significant 7 days after the initial injection of OXA and persisted for up to 17 days. Mitotherapy significantly prevented the development of both sensory alterations, and attenuated body weight loss induced by OXA. Mitotherapy also prevented spinal cord ERK1/2 activation, microgliosis and the increase in TLR4 mRNA levels. Mitotherapy prevented OIPN by inhibiting neuroinflammation and the consequent cellular overactivity in the spinal cord, presenting a potential therapeutic strategy for pain management in oncologic patients undergoing OXA treatment.

Antileishmanial Chemotherapy through Clemastine Fumarate Mediated Inhibition of the Leishmania Inositol Phosphorylceramide Synthase.

Current chemotherapeutics for leishmaniasis have multiple deficiencies, and there is a need for new safe, efficacious, and affordable medicines. This study describes a successful drug repurposing approach that identifies the over-the-counter antihistamine, clemastine fumarate, as a potential antileishmanial drug candidate. The screening for inhibitors of the sphingolipid synthase (inositol phosphorylceramide synthase, IPCS) afforded, following secondary screening against Leishmania major (Lmj) promastigotes, 16 active compounds. Further refinement through the dose response against LmjIPCS and intramacrophage L. major amastigotes identified clemastine fumarate with good activity and selectivity with respect to the host macrophage. On target engagement was supported by diminished sensitivity in a sphingolipid-deficient L. major mutant (ΔLmjLCB2) and altered phospholipid and sphingolipid profiles upon treatment with clemastine fumarate. The drug also induced an enhanced host cell response to infection indicative of polypharmacology. The activity was sustained across a panel of Old and New World Leishmania species, displaying an in vivo activity equivalent to the currently used drug, glucantime, in a mouse model of L. amazonensis infection. Overall, these data validate IPCS as an antileishmanial drug target and indicate that clemastine fumarate is a candidate for repurposing for the treatment of leishmaniasis.

Palmitate Is Increased in the Cerebrospinal Fluid of Humans with Obesity and Induces Memory Impairment in Mice via Pro-inflammatory TNF-α.

Obesity has been associated with cognitive decline, atrophy of brain regions related to learning and memory, and higher risk of developing dementia. However, the molecular mechanisms underlying these neurological alterations are still largely unknown. Here, we investigate the effects of palmitate, a saturated fatty acid present at high amounts in fat-rich diets, in the brain. Palmitate is increased in the cerebrospinal fluid (CSF) of overweight and obese patients with amnestic mild cognitive impairment. In mice, intracerebroventricular infusion of palmitate impairs synaptic plasticity and memory. Palmitate induces astroglial and microglial activation in the mouse hippocampus, and its deleterious impact is mediated by microglia-derived tumor necrosis factor alpha (TNF-α) signaling. Our results establish that obesity is associated with increases in CSF palmitate. By defining a pro-inflammatory mechanism by which abnormal levels of palmitate in the brain impair memory, the results further suggest that anti-inflammatory strategies may attenuate memory impairment in obesity.

Serotonin activates glycolysis and mitochondria biogenesis in human breast cancer cells through activation of the Jak1/STAT3/ERK1/2 and adenylate cyclase/PKA, respectively.

BACKGROUND: Although produced by several types of tumours, the role of serotonin on cancer biology is yet to be understood. METHODS: The effects of serotonin (5-HT) on human breast cancer cells proliferation, signalling pathways and metabolic profile were evaluated by cytometry, western blotting, qPCR, enzymology and confocal microscopy. RESULTS: Our results revealed that incubation of MCF-7 cells with 10 µM 5-HT increased cell growth rate by 28%, an effect that was prevented by the 5-HTR2A/C antagonist, ketanserin. Conversely, increasing concentrations of 5-HT promoted glucose consumption and lactate production by MCF-7 cells. We also showed that increased glucose metabolism is provoked by the upregulation of pyruvate kinase M2 (PKM2) isoform through 5-HTR2A/C-triggered activation of Jak1/STAT3 and ERK1/2 subcellular pathways. However, we noticed a decrease in the rate of produced lactate per consumed glucose as a function of the hormone concentration, suggesting a disruption of the Warburg effect. The latter effect is due to 5-HTR2A/C-dependent mitochondrial biogenesis and metabolism, which is triggered by adenylyl cyclase/PKA, enhancing the oxidation of lactate within these cells. CONCLUSIONS: We showed that serotonin, through 5-HTR2A/C, interferes with breast cancer cells proliferation and metabolism by triggering two distinct signalling pathways: Jak1/STAT3 that boosts glycolysis through upregulation of PKM2, and adenylyl cyclase/PKA that enhances mitochondrial biogenesis.

Zika virus replicates in adult human brain tissue and impairs synapses and memory in mice.

Neurological complications affecting the central nervous system have been reported in adult patients infected by Zika virus (ZIKV) but the underlying mechanisms remain unknown. Here, we report that ZIKV replicates in human and mouse adult brain tissue, targeting mature neurons. ZIKV preferentially targets memory-related brain regions, inhibits hippocampal long-term potentiation and induces memory impairment in adult mice. TNF-α upregulation, microgliosis and upregulation of complement system proteins, C1q and C3, are induced by ZIKV infection. Microglia are found to engulf hippocampal presynaptic terminals during acute infection. Neutralization of TNF-α signaling, blockage of microglial activation or of C1q/C3 prevent synapse and memory impairment in ZIKV-infected mice. Results suggest that ZIKV induces synapse and memory dysfunction via aberrant activation of TNF-α, microglia and complement. Our findings establish a mechanism by which ZIKV affects the adult brain, and point to the need of evaluating cognitive deficits as a potential comorbidity in ZIKV-infected adults.

Late Cognitive Consequences of Gestational Diabetes to the Offspring, in a New Mouse Model.

Gestational diabetes mellitus (GD) is a form of insulin resistance triggered during gestation, which affects approximately 10% of pregnant women. Although previously considered a transient condition with few long-term consequences, growing evidence suggest that GD may be linked to permanent metabolic and neurologic changes in the offspring. Currently available GD models fail to recapitulate the full spectrum of this disease, thus providing limited information about the true burden of this condition. Here, we describe a new mouse model of GD, based on the administration of an insulin receptor antagonist (S961, 30 nmol/kg s.c. daily) during pregnancy. Pregnant mice developed increased fasting glycemia and glucose intolerance in the absence of maternal obesity, with a return to normoglycemia shortly after parturition. Moreover, we showed that the adult offspring of GD dams presented pronounced metabolic and cognitive dysfunction when exposed to short-term high-fat diet (HFD). Our data demonstrate that S961 administration to pregnant mice comprises a valuable approach to study the complex pathophysiology of GD, as well as strategies focused on prevention and treatment of both the mother and the offspring. Our findings suggest that the offspring of GD mothers are more susceptible to metabolic and cognitive impairments when exposed to high-fat diet later in life, thus indicating that approaches to prevent and treat these late effects should be pursued.

Acute and chronic neurological consequences of early-life Zika virus infection in mice.

Although congenital Zika virus (ZIKV) exposure has been associated with microcephaly and other neurodevelopmental disorders, long-term consequences of perinatal infection are largely unknown. We evaluated short- and long-term neuropathological and behavioral consequences of neonatal ZIKV infection in mice. ZIKV showed brain tropism, causing postnatal-onset microcephaly and several behavioral deficits in adulthood. During the acute phase of infection, mice developed frequent seizures, which were reduced by tumor necrosis factor-α (TNF-α) inhibition. During adulthood, ZIKV replication persisted in neonatally infected mice, and the animals showed increased susceptibility to chemically induced seizures, neurodegeneration, and brain calcifications. Altogether, the results show that neonatal ZIKV infection has long-term neuropathological and behavioral complications in mice and suggest that early inhibition of TNF-α-mediated neuroinflammation might be an effective therapeutic strategy to prevent the development of chronic neurological abnormalities.

Brain-Defective Insulin Signaling Is Associated to Late Cognitive Impairment in Post-Septic Mice.

Sepsis survivors frequently develop late cognitive impairment. Because little is known on the mechanisms of post-septic memory deficits, there are no current effective approaches to prevent or treat such symptoms. Here, we subjected mice to severe sepsis induced by cecal ligation and puncture (CLP) and evaluated the sepsis-surviving animals in the open field, novel object recognition (NOR), and step-down inhibitory avoidance (IA) task at different times after surgery. Post-septic mice (30 days post-surgery) failed in the NOR and IA tests but exhibited normal performance when re-evaluated 45 days after surgery. Cognitive impairment in post-septic mice was accompanied by reduced hippocampal levels of proteins involved in synaptic plasticity, including synaptophysin, cAMP response element-binding protein (CREB), CREB phosphorylated at serine residue 133 (CREBpSer133), and GluA1 phosphorylated at serine residue 845 (GluA1pSer845). Expression of tumor necrosis factor α (TNF-α) was increased and brain insulin signaling was disrupted, as indicated by increased hippocampal IRS-1 phosphorylation at serine 636 (IRS-1pSer636) and decreased phosphorylation of IRS-1 at tyrosine 465 (IRS-1pTyr465), in the hippocampus 30 days after CLP. Phosphorylation of Akt at serine 473 (AktpSer473) and of GSK3 at serine 9 (GSK3ßpSer9) were also decreased in hippocampi of post-septic animals, further indicating that brain insulin signaling is disrupted by sepsis. We then treated post-septic mice with liraglutide, a GLP-1 receptor agonist with insulinotropic activity, or TDZD-8, a GSK3ß inhibitor, which rescued NOR memory. In conclusion, these results establish that hippocampal inflammation and disrupted insulin signaling are induced by sepsis and are linked to late memory impairment in sepsis survivors.

Brain infusion of α-synuclein oligomers induces motor and non-motor Parkinson's disease-like symptoms in mice.

Parkinson's disease (PD) is characterized by motor dysfunction, which is preceded by a number of non-motor symptoms including olfactory deficits. Aggregation of α-synuclein (α-syn) gives rise to Lewy bodies in dopaminergic neurons and is thought to play a central role in PD pathology. However, whether amyloid fibrils or soluble oligomers of α-syn are the main neurotoxic species in PD remains controversial. Here, we performed a single intracerebroventricular (i.c.v.) infusion of α-syn oligomers (α-SYOs) in mice and evaluated motor and non-motor symptoms. Familiar bedding and vanillin essence discrimination tasks showed that α-SYOs impaired olfactory performance of mice, and decreased TH and dopamine levels in the olfactory bulb early after infusion. The olfactory deficit persisted until 45days post-infusion (dpi). α- SYO-infused mice behaved normally in the object recognition and forced swim tests, but showed increased anxiety-like behavior in the open field and elevated plus maze tests 20 dpi. Finally, administration of α-SYOs induced late motor impairment in the pole test and rotarod paradigms, along with reduced TH and dopamine content in the caudate putamen, 45 dpi. Reduced number of TH-positive cells was also seen in the substantia nigra of α-SYO-injected mice compared to control. In conclusion, i.c.v. infusion of α-SYOs recapitulated some of PD-associated non-motor symptoms, such as increased anxiety and olfactory dysfunction, but failed to recapitulate memory impairment and depressive-like behavior typical of the disease. Moreover, α-SYOs i.c.v. administration induced motor deficits and loss of TH and dopamine levels, key features of PD. Results point to α-syn oligomers as the proximal neurotoxins responsible for early non-motor and motor deficits in PD and suggest that the i.c.v. infusion model characterized here may comprise a useful tool for identification of PD novel therapeutic targets and drug screening.

Capsular Contracture In Silicone Breast Implants: Insights From Rat Models.

Breast augmentation with silicone implants is one of the most common procedures performed by plastic surgeons around the world. Capsular contracture is a frequent complication in breast augmentation and reconstructive surgery, that requires invasive intervention. The inflammatory response to implanted mammary prostheses appears to be directly associated to capsular contracture. This review discusses the evidences from rat models studies, on the role of inflammation and fibrosis in capsular contraction and its relation to silicone breast implants surface.

Toxicological Evaluation of Anti-Scrapie Trimethoxychalcones and Oxadiazoles.

An altered form of the cellular prion protein, the PrPScor PrPRes, is implicated in the occurrence of the still untreatable transmissible spongiform encephalopathies. We have previously synthesized and characterized aromatic compounds that inhibit protease-resistant prion protein (PrPRes) accumulation in scrapie-infected cells. These compounds belong to different chemical classes, including acylhydrazones, chalcones and oxadiazoles. Some of the active compounds were non-toxic to neuroblastoma cells in culture and seem to possess drugable properties, since they are in agreement with the Lipinski´s rule of 5 and present desirable pharmacokinetic profiles as predicted in silico. Before the evaluation of the in vivo efficacy of the aromatic compounds in scrapie-infected mice, safety assessment in healthy mice is needed. Here we used Swiss mice to evaluate the acute toxicity profile of the six most promising anti-prionic compounds, the 2,4,5-trimethoxychalcones (J1, J8, J20 and J35) and the 1,3,4-oxadiazoles (Y13 and Y17). One single oral administration (300 mg/kg) of J1, J8, J20, J35, Y13 and Y17 or repeated intraperitoneal administration (10 mg/kg, 3 times a week, for 4 weeks) of J1, J8 and J35, did not elicit toxicity in mice. We strongly believe that the investigated trimethoxychalcones and oxadiazoles are interesting compounds to be further analyzed in vivo against prion diseases.

Alzheimer-associated Aß oligomers impact the central nervous system to induce peripheral metabolic deregulation.

Alzheimer's disease (AD) is associated with peripheral metabolic disorders. Clinical/epidemiological data indicate increased risk of diabetes in AD patients. Here, we show that intracerebroventricular infusion of AD-associated Aß oligomers (AßOs) in mice triggered peripheral glucose intolerance, a phenomenon further verified in two transgenic mouse models of AD. Systemically injected AßOs failed to induce glucose intolerance, suggesting AßOs target brain regions involved in peripheral metabolic control. Accordingly, we show that AßOs affected hypothalamic neurons in culture, inducing eukaryotic translation initiation factor 2α phosphorylation (eIF2α-P). AßOs further induced eIF2α-P and activated pro-inflammatory IKKß/NF-κB signaling in the hypothalamus of mice and macaques. AßOs failed to trigger peripheral glucose intolerance in tumor necrosis factor-α (TNF-α) receptor 1 knockout mice. Pharmacological inhibition of brain inflammation and endoplasmic reticulum stress prevented glucose intolerance in mice, indicating that AßOs act via a central route to affect peripheral glucose homeostasis. While the hypothalamus has been largely ignored in the AD field, our findings indicate that AßOs affect this brain region and reveal novel shared molecular mechanisms between hypothalamic dysfunction in metabolic disorders and AD.

The role of CXCR2 chemokine receptors in the oral squamous cell carcinoma.

This study evaluated the relevance of CXCR2 chemokine receptors in oral squamous cell carcinoma, by means of in vitro and in vivo approaches. The in vitro incubation of the selective and non-peptide CXCR2 receptor antagonist N-(2-hydroxy-4-nitrophenyl)-N9-(2-bromophenyl) Urea (SB225002; 25 to 800 nM) produced a time- and concentration-dependent inhibition of SCC158 (rat) and HN30 (human) cell lines viability. Conversely, this antagonist did not significantly affect the viability of the immortalized keratinocyte lineage, HaCaT. Additionally, the incubation of human IL-8 and rat CINC-1 CXCR2 agonists produced a concentration-related increase on HN30 and SCC158 proliferation. The submucosal injection of SCC158 cells (5 × 10(6) cells) into the tongue of Fischer 344 rats induced tumor development, which displayed typical clinical features. Immunohistochemical analysis of rat tongue biopsies revealed a marked increase of CXCR2 receptor immunoreactivity, which was accompanied by augumented expression of VEGF and caspase-3. Our data suggests an important role for CXCR2 receptors in oral squamous cell carcinoma.

In vivo host interactions with mineral trioxide aggregate and calcium hydroxide: inflammatory molecular signaling assessment.

INTRODUCTION: Mineral trioxide aggregate (MTA) and calcium hydroxide [Ca(OH)(2)] are promising biomaterials for stimulating dentinogenesis and cementogenesis. This research was undertaken to understand how MTA and CA(OH)(2) participate in the inflammatory, healing, and biomineralization processes. In this part of the study, we evaluated inflammatory signaling molecules promoted by in vivo host interaction with MTA and Ca(OH)(2). METHODS: Human dentin tubes were filled with ProRoot MTA (Dentsply Tulsa Dental, Tulsa, OK), Ca(OH)(2), or kept empty. After 12 hours and 1, 3, 7, 15, 30, and 60 days of implantation in subcutaneous tissues in the backs of mice, the tubes and surrounding tissues were retrieved for cytokine level quantification and histological and immunohistochemical analysis. RESULTS: MTA and Ca(OH)(2) induced proinflammatory cytokine up-regulation for up to 3 days. Moreover, interleukin-10 overexpression was noted on the tissue in contact with the biomaterials during the acute phase of the inflammatory reaction. Immunohistochemical analyses showed an increased expression of myeloperoxidase, nuclear factor kappa B (NF-κB), cyclooxygenase-2, inducible nitric oxide synthase enzymes, and vascular endothelial growth factor on day 1 for all groups. CONCLUSIONS: MTA and Ca(OH)(2) increased the activation of the NF-κB signaling system on day 1 for all groups. This finding can be associated with a proinflammatory and pro-wound healing environment, which was promoted earlier by MTA.

Primary teeth show less protecting factors against root resorption.

BACKGROUND: Physiological root resorption differentiates primary from permanent teeth. The understanding of what protects and regulates root resorption might help to develop therapies to its control. AIM: To verify the presence and distribution of ECRM and the expression of CK14, OPG, TRAP and COX-2 in the periodontal ligament (PDL) of human primary and permanent teeth. Design. Eight primary teeth undergoing physiological or pathological root resorption and 4 permanent teeth were immunohistochemically processed for CK14, TRAP, COX-2 and OPG expression. RESULTS: PDL from primary and permanent teeth showed similar morphological features; however, fewer ECRM clusters and higher immunoreactivity to CK14 were found in primary PDL. In permanent teeth, ECRM were distributed along the entire PDL tissue. Howship's lacunae were found only in primary teeth, associated with the presence of TRAP-positive cells and increase in COX-2 expression. OPG expression in primary PDL was detected in nonresorptive cervical areas and in lacunae showing reparative tissue. It was observed higher expression of OPG in all permanent teeth when compared to primary specimens. CONCLUSIONS: It may be concluded that PDL from primary teeth shows less ECRM clusters and lower expression of OPG. These features may be associated with lower protection against root resorption in primary teeth.

Glucose-dependent insulinotropic peptide receptor expression in the hippocampus and neocortex of mesial temporal lobe epilepsy patients and rats undergoing pilocarpine induced status epilepticus.

The glucose-dependent insulinotropic peptide receptor (GIPR) has been implicated with neuroplasticity and may be related to epilepsy. GIPR expression was analyzed by immunohistochemistry in the hippocampus (HIP) and neocortex (Cx) of rats undergoing pilocarpine induced status epilepticus (Pilo-SE), and in three young male patients with left mesial temporal lobe epilepsy related to hippocampal sclerosis (MTLE-HS) treated surgically. A combined GIPR immunohistochemistry and Fluoro-Jade staining was carried out to investigate the association between the GIPR expression and neuronal degeneration induced by Pilo-SE. GIPR was expressed in the cytoplasm of neurons from the HIP CA subfields, dentate gyrus (DG) and Cx of animals and human samples. The GIPR expression after the Pilo-SE induction increases significantly in the HIP after 1h and 5 days, but not after 12h or 50 days. In the Cx, the GIPR expression increases after 1h, 12h and 5 days, but not 50 days after the Pilo-SE. The expression of GIPR 12h after Pilo-SE was inversely proportional to the Fluoro-Jade staining intensity. In the human tissue, GIPR expression patterns were similar to those observed in chronic Pilo-SE animals. No Fluoro-Jade stained cells were observed in the human sample. GIPR is expressed in human HIP and Cx. There was a time and region dependent increase of GIPR expression in the HIP and Cx after Pilo-SE that was inversely associated to neuronal degeneration.

Vascular endothelial growth factor overexpression positively modulates the characteristics of periprosthetic tissue of polyurethane-coated silicone breast implant in rats.

BACKGROUND: Capsular contracture is one of the most common complications associated with silicone breast implants. The surface of the implant is one of the factors often associated with the occurrence of capsular contracture. In this study, the authors evaluated the differences in morphologic and molecular characteristics of the capsule formed around polyurethane-coated versus textured-surface silicone implants in rats, mainly the modifications in angiogenesis and the expression of vascular endothelial growth factor (VEGF). METHODS: A pocket was performed on the animal's back, where the silicone implants were introduced. Two groups of animals received a polyurethane-coated silicone implant and the other groups received a textured-surface silicone implant, and the capsules around the prostheses were submitted to histologic and immunohistochemistry analysis, 30 or 90 days after surgery. RESULTS: The capsules around the polyurethane-coated silicone prostheses were significantly thicker than the textured-surface silicone implants. Furthermore, the layer adjacent to the polyurethane-coated silicone implants was more cellular and irregular than the layer around the textured-surface silicone implants. Textured implant periprosthetic capsules presented fewer inflammatory cells and less vascularization than the polyurethane-coated silicone implants. The collagen layer of periprosthetic tissue of textured implants appears to be more continuous and aligned in parallel fashion than polyurethane-coated implants. Immunohistochemical analysis revealed high levels of transforming growth factor-ß and VEGF in the capsules around the polyurethane-coated silicone implants when compared with the textured-surface silicone implants. CONCLUSION: These findings suggest that the intense VEGF expression in capsules around the polyurethane-coated silicone implant is able to improve the tissue vascularization, resulting in a softer capsule compared with the textured-surface silicone implant.

Atorvastatin prevents hippocampal cell death, neuroinflammation and oxidative stress following amyloid-ß(1-40) administration in mice: evidence for dissociation between cognitive deficits and neuronal damage.

The accumulation of amyloid-beta (Aß) peptides in the brain of human and rodents has been associated with the activation of glial cells, neuroinflammatory and oxidative responses, and cognitive deficits. These oxidative changes leave glutamate transporters more vulnerable and may result in reduction of their functions, resulting in excitotoxic damage. Herein, we evaluated the effects of atorvastatin, a HMG-CoA reductase inhibitor, in molecular and behavioral alterations induced by a single intracerebroventricular injection of aggregated Aß(1-40) (400 pmol) in mice. An increased glial fibrillar acidic protein (GFAP) expression and cyclooxygenase-2 (COX-2) levels, as well as increased lipid peroxidation and impairment in the glutathione antioxidant system and cell degeneration was found in the hippocampus of Aß(1-40)-treated mice. Aß(1-40) also induced a marked decrease in glutamatergic transporters (GLAST and GLT-1) expression and in l-[³H] glutamate uptake in mice hippocampus, in addition to spatial learning and memory deficits. Atorvastatin (10 mg/kg/day v.o.) was administered after Aß(1-40) injection and through seven consecutive days. Atorvastatin treatment was neuroprotective against cell degeneration induced by Aß(1-40), reducing inflammatory and oxidative responses and increasing the expression of glutamatergic transporters. On the other hand, atorvastatin did not reverse the cognitive impairments and failed to alter the hippocampal glutamate uptake in Aß(1-40)-treated mice. These results reinforce and extend the notion of the potential neuroprotective action of atorvastatin against the neuronal toxicity induced by Aß(1-40). In addition, the present findings suggest that the spatial learning and memory deficits induced by Aß peptides in rodents may not be entirely related to neuronal damage.