Metformin and fluoxetine improve depressive-like behavior in a murine model of Parkinsons disease through the modulation of neuroinflammation, neurogenesis and neuroplasticity.

Thereabout 30-40% of patients with Parkinson's Disease (PD) also have depression contributing to the loss of quality of life. Among the patients who treat depression, about 50% do not show significant improvement due to the limited efficacy of the treatment. So far, there are no effective disease-modifying treatments that can impede its progression. The current clinical approach is based on symptom management. Nonetheless, the reuse of drugs with excellent safety profiles represents an attractive alternative strategy for treating of different clinical aspects of PD. In this study, we evaluated the effects of metformin separately and associated with fluoxetine on depressive like-behavior and motor alterations in experimental Parkinson's disease. C57BL6 mice were induced with rotenone (2.5 mg/kg/day) for 20 days and treated with metformin (200 mg/kg/day) and fluoxetine (10 mg/kg/day) from the 5th day of induction. The animals were submitted to Sucrose Preference, Tail Suspension, and rotarod tests. Hippocampus, prefrontal cortex, and substantia nigra were dissected for molecular and morphological analysis. Metformin and fluoxetine prevented depressive-like behavior and improved motor impairment and increased TH nigral positive cells. Metformin and fluoxetine also reduced IBA-1 and GFAP positive cells in the hippocampus. Moreover, metformin reduced the phospho-NF-kB, IL-1ß in the prefrontal cortex and iNOS levels in the hippocampus. Both metformin and fluoxetine increased neurogenesis by increasing KI67, but only the combined treatment increased neuronal survival by NeuN positive cells in the hippocampus. In addition, fluoxetine reduced cell death, decreasing caspase-3 and PARP-1 levels. Lastly, metformin potentiated the effect of fluoxetine on neuroplasticity by increasing BDNF positive cells. Metformin has antidepressant and antiparkinsonian potential due to anti-inflammatory neurogenic, and neuroplasticity-inducing effects when combined with fluoxetine.

Metformin prevents p-tau and amyloid plaque deposition and memory impairment in diabetic mice.

Insulin deficiency or resistance can promote dementia and hallmarks of Alzheimer's disease (AD). The formation of neurofibrillary tangles of p-TAU protein, extracellular Aß plaques, and neuronal loss is related to the switching off insulin signaling in cognition brain areas. Metformin is a biguanide antihyperglycemic drug used worldwide for the treatment of type 2 diabetes. Some studies have demonstrated that metformin exerts neuroprotective, anti-inflammatory, anti-oxidant, and nootropic effects. This study aimed to evaluate metformin's effects on long-term memory and p-Tau and amyloid ß modulation, which are hallmarks of AD in diabetic mice. Swiss Webster mice were distributed in the following experimental groups: control; treated with streptozotocin (STZ) that is an agent toxic to the insulin-producing beta cells; STZ + metformin 200 mg/kg (M200). STZ mice showed significant augmentation of time spent to reach the target box in the Barnes maze, while M200 mice showed a significant time reduction. Moreover, the M200 group showed reduced GFAP immunoreactivity in hippocampal dentate gyrus and CA1 compared with the STZ group. STZ mice showed high p-Tau levels, reduced p-CREB, and accumulation of ß-amyloid (Aß) plaque in hippocampal areas and corpus callosum. In contrast, all these changes were reversed in the M200 group. Protein expressions of p-Tau, p-ERK, pGSK3, iNOS, nNOS, PARP, Cytochrome c, caspase 3, and GluN2A were increased in the parietal cortex of STZ mice and significantly counteracted in M200 mice. Moreover, M200 mice also showed significantly high levels of eNOS, AMPK, and p-AKT expression. In conclusion, metformin improved spatial memory in diabetic mice, which can be associated with reducing p-Tau and ß-amyloid (Aß) plaque load and inhibition of neuronal death.

Sildenafil Alleviates Murine Experimental Autoimmune Encephalomyelitis by Triggering Autophagy in the Spinal Cord.

Multiple Sclerosis (MS) is a neuroinflammatory and chronic Central Nervous System (CNS) disease that affects millions of people worldwide. The search for more promising drugs for the treatment of MS has led to studies on Sildenafil, a phosphodiesterase type 5 Inhibitor (PDE5I) that has been shown to possess neuroprotective effects in the Experimental Autoimmune Encephalomyelitis (EAE), an animal model of MS. We have previously shown that Sildenafil improves the clinical score of EAE mice via modulation of apoptotic pathways, but other signaling pathways were not previously covered. Therefore, the aim of the present study was to further investigate the effects of Sildenafil treatment on autophagy and nitrosative stress signaling pathways in EAE. 24 female C57BL/6 mice were divided into the following groups: (A) Control - received only water; (B) EAE - EAE untreated mice; (C) SILD - EAE mice treated with 25mg/kg of Sildenafil s.c. The results showed that EAE mice presented a pro-nitrosative profile characterized by high tissue nitrite levels, lowered levels of p-eNOS and high levels of iNOS. Furthermore, decreased levels of LC3, beclin-1 and ATG5, suggests impaired autophagy, and decreased levels of AMPK in the spinal cord were also detected in EAE mice. Surprisingly, treatment with Sildenafil inhibited nitrosative stress and augmented the levels of LC3, beclin-1, ATG5, p-CREB and BDNF and decreased mTOR levels, as well as augmented p-AMPK. In conclusion, we propose that Sildenafil alleviates EAE by activating autophagy via the eNOS-NO-AMPK-mTOR-LC3-beclin1-ATG5 and eNOS-NO-AMPK-mTOR-CREB-BDNF pathways in the spinal cord.

Effect of sildenafil on neuroinflammation and synaptic plasticity pathways in experimental autoimmune encephalomyelitis.

Multiple sclerosis (MS) is a chronic immuno-inflammatory disease of the central nervous system characterized by demyelination and axonal damage. Cognitive changes are common in individuals with MS since inflammatory molecules secreted by microglia interfere with the physiological mechanisms of synaptic plasticity. According to previous data, inhibition of PDE5 promotes the accumulation of cGMP, which inhibits neuroinflammation and seems to improve synaptic plasticity and memory. The present study aimed to evaluate the effect of sildenafil on the signaling pathways of neuroinflammation and synaptic plasticity in experimental autoimmune encephalomyelitis (EAE). C57BL/6 mice were divided into three experimental groups (n = 10/group): (a) Control; (b) EAE; (c) EAE + sild (25 mg/kg/21 days). Sildenafil was able to delay the onset and attenuate the severity of the clinical symptoms of EAE. The drug also reduced the infiltration of CD4+ T lymphocytes and their respective IL-17 and TNF-α cytokines. Moreover, sildenafil reduced neuroinflammation in the hippocampus (assessed by the reduction of inflammatory markers IL-1ß, pIKBα and pNFkB and reactive gliosis, as well as elevating the inhibitory cytokines TGF-ß and IL-10). Moreover, sildenafil induced increased levels of NeuN, BDNF and pCREB, protein kinases (PKA, PKG, and pERK) and synaptophysin, and modulated the expression of the glutamate receptors AMPA and NMDA. The present findings demonstrated that sildenafil has therapeutic potential for cognitive deficit associated with multiple sclerosis.

Tadalafil restores long-term memory and synaptic plasticity in mice with hepatic encephalopathy.

BACKGROUND AND AIM: Tadalafil displays important neuroprotective effects in experimental models of neurodegenerative diseases, however its mechanisms of action remain poorly understood. The aim of the present study was to investigate the action of Tadalafil on learning and memory, neuroinflammation, glial cell activation and neuroprotection in the experimental model of hepatic encephalopathy (HE) induced by Thioacetamide (TAA) in mice. METHODS: Mice received intraperitoneal injections of TAA, for 3 consecutive days, reaching the final dose of 600 mg/kg. Tadalafil 15 mg/kg body weight was administered by gavage during 15 days after TAA induction. Mice underwent a Barnes maze for learning and memory evaluation. RESULTS: Animals with hepatic encephalopathy showed reduced learning and spatial memory in the Barnes Maze, presented astrocyte and microglia activation and increased neuroinflammatory markers such as TNF-α, IL-1ß, IL-6, p-p38, p-ERK and p-NF-kB. In addition, the signaling pathway PKA/PKG/CREB/BDNF/NeuN/synaptophysin and glutamate receptors were deregulated by TAA. Tadalafil treatment regulated the inflammation signaling pathways restoring learning and spatial memory. CONCLUSION: Tadalafil significantly reduced neuroinflammation, promoted neuroprotection and plasticity, regulated the expression of hippocampal glutamate receptor and restored spatial learning ability and memory.

Preventive role of metformin on peripheral neuropathy induced by diabetes.

Metformin is the first line drug in the treatment of type 2 diabetes, however, little is known about its therapeutic potential to prevent or delay damage to the peripheral nerve. Thus, the aim of this study was to investigate whether metformin is able to attenuate the neuroinflammatory response in sciatic nerve of insulin-dependent diabetic mice. Swiss Webster mice were divided into four groups: Control, Diabetic (STZ), Diabetic +100 mg/kg/day of metformin (STZ + M100) and Diabetic +200 mg/kg/day of metformin. Diabetes was induced by streptozotocin (90 mg/kg, i.p.). Only animals with glycemia ≥270 mg/dl were considered diabetics. Metformin prevented atrophy of myelinated axons, and reduced expression of inflammatory mediators (interleukin-1ß, inducible nitric oxide synthase and nitric oxide). However, treatment with 200 mg of metformin was more effective in increasing neurotrophic (myelin basic protein and neural growth factor), angiogenic (vascular endothelial growth factor) and anti-inflammatory (inhibitor kappa B-alpha and interleukin 10) factors. Thus, metformin treatment, especially at the dose of 200 mg, protected the nerve from damages related to chronic hyperglycemia.

A new diethylcarbamazine formulation (NANO-DEC) as a therapeutic tool for hepatic fibrosis.

The aim of the present study was to assess if the uninterrupted and prolonged administration of nanoparticles containing diethylcarbamazine (NANO-DEC) would cause liver, kidney and heart toxicity and then analyze for the first time its action in model of liver fibrosis. Thus, NANO-DEC was administered in C57BL/6 mice daily for 48 days, and at the end the blood was collected for biochemical analyzes. In the long-term administration assay, the evaluation of serological parameters (CK-MB, creatinine, ALT, AST and urea) allowed the conclusion that NANO-DEC prolonged administration did not cause hepatic, renal and cardiac damage. For fibrosis assays, C57BL/6 mice were divided into six groups: 1) control (Cont); 2) carbon tetrachloride (CCl4); 3) CCl4 + DEC 25 mg/kg; 4) CCl4 + DEC 50 mg/kg; 5) CCl4 + NANO-DEC 5 mg/kg and 6) CCl4 + NANO-DEC 12.5 mg/kg. Carbon tetrachloride induced hepatic fibrosis observed through increased inflammatory (TNF-α, IL-1ß, COX-2, NO and iNOS) and fibrotic markers (TGF-ß and TIMP-1), changes in the hepatic morphology, high presence of collagen fibers and elevated serum levels of AST, ALT and ALP. Treatment with NANO-DEC exhibited a superior anti-inflammatory and anti-fibrotic effects compared to the DEC traditional formulation, restoring liver morphology, reducing the content of collagen fibers and serological parameters, besides decreasing the expression of inflammatory and fibrotic markers. The present formulation of nanoencapsulated DEC is a well tolerated anti-inflammatory and anti-fibrotic drug and therefore could be a potential therapeutic tool for the treatment of chronic liver disorders.

Sildenafil ameliorates EAE by decreasing apoptosis in the spinal cord of C57BL/6 mice.

Apoptosis is one form of cell death that is intimately related to health and pathological conditions. In most neuroinflammatory and/or neurodegenerative diseases, apoptosis is associated with disease development and pathology and inhibition of this process leads to considerable amelioration. It is becoming evident that apoptosis also participates in the pathogenesis of Multiple Sclerosis (MS) and its animal model, Experimental Autoimmune Encephalomyelitis (EAE). Drugs such as Sildenafil, a Phosphodiesterase type 5 Inhibitor (PDE5I), have proven to be neuroprotective in MS models. However, it is not known whether Sildenafil is able to modulate cell death, specifically apoptosis, in EAE mice. Therefore, the aim of this study was to determine the effects of Sildenafil on extrinsic and intrinsic apoptosis pathways in the spinal cord of C57BL/6 mice with EAE. TUNEL analysis showed that EAE mice had elevated number of TUNEL+ cells and that treatment with Sildenafil led to reduced number of dying cells, indicating that Sildenafil was able to inhibit cell death. We observed that both extrinsic and intrinsic pathways of apoptosis were governing the dynamics of EAE progression. We showed that in EAE mice there were increased levels of extrinsic (Caspase-8, -3, TNF-α, FADD) and intrinsic (Caspase-9, Bax and Cytochrome C) apoptosis markers. Bcl-2, an anti-apoptotic protein, was downregulated in EAE mice. We also demonstrated that EAE mice had increased levels of non-caspase mediators of cell survival/cell death (p-IκBα and p-MAPK-p38). Besides, EAE mice presented augmented demyelination. Nevertheless, this is the first research to demonstrate that Sildenafil, when administered concomitant to disease induction, modulated the expression of pro- and anti-apoptotic proteins of the extrinsic and intrinsic pathways, as well as diminished the expression of non-caspase mediators and promoted remyelination in the spinal cord, indicating neuroprotective effects. Thus, the present study demonstrated that Sildenafil inhibits apoptosis by two distinct, although interconnected, mechanisms: directly by modulating caspase expression (through extrinsic and intrinsic pathways) and indirectly by modulating the expression of molecules involved in cell death and/or cell survival.

New thiazolidinedione LPSF/GQ-2 inhibits NFκB and MAPK activation in LPS-induced acute lung inflammation.

Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) are responsible for high mortality rates in critical patients. Despite >50 years of intensive research, there is no pharmacologically effective treatment to treat ALI. PPARs agonists, chemically named thiazolidinediones (TZDs) have emerged as potential drugs for the treatment of ALI and ARDS due to their anti-inflammatory efficacy. The present study aims to evaluate the potential anti-inflammatory effects of new TZDs derivatives, LPSF/GQ-2 and LPSF/RA-4, on ALI induced by LPS. BALB/c mice were divided into five groups: 1) Control; 2) LPS intranasal 25 µg; 3) LPSF/GQ-2 30 mg/kg + LPS; 4) LPSF/RA-4 20 mg/kg + LPS; and 5) DEXA 1 mg/Kg + LPS. BALF analyses revealed that LPSF/GQ-2 and LPSF/RA-4 reduced NO levels in BALF and inflammatory cell infiltration induced by LPS. MPO levels were also reduced by the LPSF/GQ-2 and LPSF/RA-4 pre-treatments. In contrast, histopathological analyses showed better tissue protection with LPSF/GQ-2 than DEXA and LPSF/RA-4 groups. Similarly, LPSF/GQ-2 reduced inflammatory markers (IL-1, iNOS, TNFα, IL-1ß, IL-6) better than LPSF/RA-4. The LPSF/GQ-2 anti-inflammatory action could be attributed to the inhibition of NFκB, ERK, p38, and PARP pathways. In contrast, LPSF/RA-4 had no effect on the expression of p38, JNK, NFκB. The present study indicates that LPSF/GQ-2 presents a potential therapeutic role as an anti-inflammatory drug for ALI.

Diethylcarbamazine attenuates the expression of pro-fibrogenic markers and hepatic stellate cells activation in carbon tetrachloride-induced liver fibrosis.

BACKGROUND AND AIM: While diethylcarbamazine citrate (DEC) displays important anti-inflammatory effects in experimental models of liver injury, the mechanisms of its action remain poorly understood. The aim of the present study was to investigate the fibrolytic potential of DEC. METHODS: Mice receive two injections of carbon tetrachloride (CCl4) per week for 8 weeks. DEC 50 mg/kg body weight was administered through drinking water during the last 12 days of liver injury. RESULTS: The expression of hepatic stellate cells (HSCs) activation markers, including smooth muscle α-actin (α-SMA), collagen I, transforming growth factor-ß 1 (TGF-ß1), matrix metalloproteinase-2 (MMP-2) and tissue inhibitor of metalloproteinase-1 (TIMP-1) was assessed. The influence of DEC on the intracellular MAPK pathways of the HSCs (JNK and p38 MAPK) was also estimated. DEC inhibited HSCs activation measured as the production of α-SMA and collagen I. In addition, it down regulated the production of TGF-ß1 and TIMP-1, and concomitantly increased MMP-2 activity. Furthermore, DEC significantly inhibited the activation of the JNK and p38 MAPK signaling pathways. CONCLUSIONS: In conclusion, DEC significantly attenuated the severity of CCl4-induced liver injury and the progression of liver fibrosis, exerting a potential fibrolytic effect in the CCl4-induced fibrosis model.

AMPK activation: Role in the signaling pathways of neuroinflammation and neurodegeneration.

Adenosine monophosphate-activated protein kinase (AMPK) is an evolutionarily conserved sensor of cellular energy status and has been reported to be involved in chronic inflammatory disorders. AMPK is expressed in immune cells, such as dendritic cells, macrophages, lymphocytes and neutrophils, and is an important regulator of inflammatory responses through the regulation of complex signaling networks in part by inhibiting downstream cascade pathways, such as nuclear factor kB, which is a key regulator of innate immunity and inflammation, as well as acting as a negative regulator of toll-like receptors. Recent data suggest that AMPK dysregulation may participate in neurodegenerative diseases, such as multiple sclerosis, Alzheimer's disease, Parkinson's disease, Huntington's disease, amyotrophic lateral sclerosis and neuropathies. However, there are conflicting reports on the benefits or detrimental effects of AMPK in distinct pathological conditions. This paper offers a review of the recent literature on the pharmacological modulation of the AMPK system as a potential molecular target in the management of neurodegenerative diseases.

Characterization and evaluation of nanoencapsulated diethylcarbamazine in model of acute hepatic inflammation.

Previous studies from our laboratory have demonstrated that Diethylcarbamazine (DEC) is a potent anti-inflammatory drug. The aim of the present study was to characterize the nanoencapsulation of DEC and to evaluate its effectiveness in a model of inflammation for the first time. C57BL/6 mice were divided into six groups: 1) Control; 2) Carbon tetrachloride (CCl4); 3) DEC 25mg/kg+CCl4; 4) DEC 50mg/kg+CCl4; 5) DEC-NANO 05mg/kg+CCl4 and 6) DEC-NANO 12.5mg/kg+CCl4. Liver fragments were stained with hematoxylin-eosin, and processed for Western blot, ELISA and immunohistochemistry. Serum was also collected for biochemical measurements. Carbon tetrachloride induced hepatic injury, observed through increased inflammatory markers (TNF-α, IL-1ß, PGE2, COX-2 and iNOS), changes in liver morphology, and increased serum levels of total cholesterol, triglycerides, TGO and TGP, LDL, as well as reduced HDL levels. Nanoparticles containing DEC were characterized by diameter, polydispersity index and zeta potential. Treatment with 12.5 nanoencapsulated DEC exhibited a superior anti-inflammatory action to the DEC traditional dose (50mg/kg) used in murine assays, restoring liver morphology, improving serological parameters and reducing the expression of inflammatory markers. The present formulation of nanoencapsulated DEC is therefore a potential therapeutic tool for the treatment of inflammatory hepatic disorders, permitting the use of smaller doses and reducing treatment time, while maintaining high efficacy.

RNA binding protein, tristetraprolin in a murine model of recurrent pregnancy loss.

Recurrent pregnancy loss is a major reproductive pathology affecting 1-5% of pregnant women worldwide. A distinct feature of this reproductive pathology is involvement of key inflammatory cytokines and transcription factors such as tumor necrosis factor alpha (TNF-α), interleukin 6 (IL-6) and nuclear factor kappa beta (NF-κB). Special classes of RNA-binding proteins regulate the transcripts of many of these important cytokines and regulatory factors via binding to the 3' untranslated regions (UTRs) and/or poly(A) tail and destabilizing/stabilizing the transcript. The tristetraprolin (TTP/ZFP36) family have been found to be potent destabilizers of the aforementioned inflammatory and cellular response cytokines. The aim of this study was to evaluate whether tristetraprolin is expressed in the placenta and involved in modulating inflammation in mouse model of lipopolysaccharide (LPS)-induced fetal loss. In this study, Swiss-albino mice were injected with LPS at gestational day 15.5 and placental tissues were harvested 6 hours post-LPS injection. Histopathology and immunohistochemistry analyses clearly revealed cellular stress and death in LPS treated placentas compared to controls. TTP protein was downregulated, while targets TNF-α and IL-6 were upregulated in LPS group compared to controls. We observed increased TTP nuclear immunolocalization corresponding with higher NF-κB nuclear localization in trophoblasts from LPS treated placentas. Our results suggest that RNA-binding proteins such as TTP are expressed and perhaps involved in the modulation of inflammation-induced pregnancy pathologies.

Effects of metformin on inflammation and short-term memory in streptozotocin-induced diabetic mice.

The aim of the present study was to analyze the action of metformin on short-term memory, glial cell activation and neuroinflammation caused by experimental diabetic encephalopathy in C57BL/6 mice. Diabetes was induced by the intraperitoneal injection of a dose of 90mg/kg of streptozotocin on two successive days. Mice with blood glucose levels ≥200dl/ml were considered diabetic and were given metformin hydrochloride at doses of 100mg/kg and 200mg/kg (by gavage, twice daily) for 21 days. On the final day of treatment, the mice underwent a T-maze test. On the 22nd day of treatment all the animals were anesthetized and euthanized. Diabetic animals treated with metformin had a higher spatial memory score. The hippocampus of the diabetic animals presented reactive gliosis, neuronal loss, NF-kB signaling activation, and high levels of IL-1 and VEGF. In addition, the T-maze test scores of these animals were low. Treatment with metformin reduced the expression of GFAP, Iba-1 (astrocyte and microglial markers) and the inflammation markers (p-IKB, IL-1 and VEGF), while enhancing p-AMPK and eNOS levels and increasing neuronal survival (Fox-1 and NeuN). Treatment with metformin also improved the spatial memory scores of diabetic animals. In conclusion, the present study showed that metformin can significantly reduce neuroinflammation and can decrease the loss of neurons in the hippocampus of diabetic animals, which can subsequently promote improvements in spatial memory.

Effects of Sildenafil Citrate and Heparin Treatments on Placental Cell Morphology in a Murine Model of Pregnancy Loss.

Lipopolysaccharide (LPS) injections during pregnancy are well established as models for pregnancy complications, including fetal growth restriction (FGR), thrombophilia, preterm labor and abortion. Indeed, inflammation, as induced by LPS injection has been described as a pivotal factor in cases of miscarriage related to placental tissue damage. The phosphodiesterase-5 inhibitor sildenafil (Viagra®) is currently used to treat FGR cases in women, while low-molecular weight heparin (Fragmin®) is a standard treatment for recurrent miscarriage (RM). However, the pathways and cellular dynamics involved in RM are not completely understood. The aim of this study was to evaluate the protective effect of sildenafil and dalteparin in a mouse model of LPS-induced abortion. Histopathology, ultrastructural analysis and immunofluorescence for P-selectin were studied in two different placental cell types: trophoblast cells and labyrinth endothelial cells. Treatment with sildenafil either alone or in combination with heparin showed the best response against LPS-induced injury during pregnancy. In conclusion, our results support the use of these drugs as future therapeutic agents that may protect the placenta against inflammatory injury in RM events. Analyses of the ultrastructure and placental immunophysiology are important to understand the mechanism underlying RM. These findings may spark future studies and aid in the development of new therapies in cases of RM.

Phosphodiesterase-5 inhibition promotes remyelination by MCP-1/CCR-2 and MMP-9 regulation in a cuprizone-induced demyelination model.

While it has recently been shown that sildenafil (Viagra®) has a protective effect on myelination/remyelination, the mechanism of this protection is still unknown. In general, cytokines, chemokines and metalloproteinases have a pro-inflammatory action, but can also exert a role in modulating glial cell activation, contributing to the balance of cell response. Investigating these molecules can contribute to clarifying the mechanisms of sildenafil neuroprotection. In addition, it is not known whether sildenafil is able to restore an already installed neurodegenerative process or if the treatment period is critical for its action. The aim of the present study was to evaluate, in a cuprizone (CPZ)-induced demyelination model, the effects and mechanisms of time-dependent treatment with sildenafil (beginning 15 days after neurodegeneration and continuing for 15 days, or starting concomitantly with neurodegeneration and continuing for 30 days) on neuroinflammation and remyelination. Neuroinflammation and demyelination induced by CPZ in rodents has been widely used as a model of multiple sclerosis (MS). In the present study, five male C57BL/6 mice aged 7-10 weeks were used per group. For four weeks, the groups received either cuprizone (CPZ) 0.2% mixed in feed or CPZ combined with the administration of sildenafil (Viagra®, Pfizer, 25 mg/kg) orally in drinking water, starting concurrently with (sild-T0) or 15 days (sild-T15) after the start of CPZ treatment. Control animals received pure food and water. The cerebella were dissected and processed for immunohistochemistry, immunofluorescence (frozen), Western blotting, Luxol fast blue staining and transmission electron microscopy. Magnetic resonance was performed for live animals, after the same treatment, using CPZ 0.3%. CPZ induced an increase in the expression of IL-1ß and a decrease in MCP-1, CCR-2, MBP and GST-pi, as well as promoting damage in the structure and ultra-structure of the myelin sheath. Interestingly, the administering of sild-T0 promoted a further increase of MMP-9, MCP-1, and CCR-2, possibly contributing to changes in the microglia phenotype, which becomes more phagocytic, cleaning myelin debris. It was also observed that, after sild-T0 treatment, the expression of GST-pi and MBP increased and the myelin structure was improved. However, sild-T15 was not efficient in all aspects, probably due to the short treatment period and to starting after the installation of the degenerative process. Therefore, the present study shows that sildenafil modulates inflammation, with the involvement of MMP-9, MCP-1, and CCR-2, and also contributes to myelin repair. These protective effects were dependent on the therapeutic strategy used. This clarification can strengthen research proposals into the mechanism of action of sildenafil and contribute to the control of neurodegenerative diseases such as MS.

Diethylcarbamazine: possible therapeutic alternative in the treatment of alcoholic liver disease in C57BL/6 mice.

Alcoholic liver disease is a major cause of chronic liver disease worldwide. Diethylcarbamazine (DEC) is a drug that has anti-inflammatory properties due to its effects on the metabolism of arachidonic acid. The present study examined the anti-inflammatory effects of DEC on the mechanisms of alcoholic liver disease. C57BL/6 mice were divided into seven groups: (i) control; (ii) DEC 50 mg/kg; (iii) alcohol; (iv) alcohol + DEC 50 mg/kg; (v) alcohol + celecoxib 50 mg/kg; (vi) alcohol + pyrrolidine dithiocarbamate 100 mg/kg; and (vii) alcohol + pyrrolidine dithiocarbamate 100 mg/kg + DEC 50 mg/kg. Liver fragments were stained with haemotoxylin-eosin and Sirius red, and processed for immunofluorescence, western blot, and immunohistochemistry. Serum was also collected for biochemical measurements. Alcohol induced liver damage, elevated collagen content, and increased expression of nuclear factor kappa-light-chain-enhancer of activated B cells and inflammatory markers (tumour necrosis factor-α, interferon-γ, interleukin-1ß, inducible nitric oxide synthase, cyclooxygenases-2, and transforming growth factor-ß). Treatment with DEC was able to reduce liver damage, collagen content, the expression of nuclear factor kappa-light-chain-enhancer of activated B cells and inflammatory markers; it also ameliorated biochemistry parameters (total cholesterol, high-density lipoprotein cholesterol, triglyceride content and aspartate aminotransferase) and increased the expression of anti-inflammatory markers (p-5' adenosine monophosphate-activated protein kinase and interleukin-10). Future clinical trials may demonstrate that oral administration of DEC may be suitable for the treatment of alcoholic liver disease and other liver diseases.

Diethylcarbamazine reduces chronic inflammation and fibrosis in carbon tetrachloride- (CCl4-) induced liver injury in mice.

This study investigated the anti-inflammatory effects of DEC on the CCl4-induced hepatotoxicity in C57BL/6 mice. Chronic inflammation was induced by i.p. administration of CCl4 0.5 µL/g of body weight through two injections a week for 6 weeks. DEC (50 mg/kg) was administered by gavage for 12 days before finishing the CCl4 induction. Histological analyses of the DEC-treated group exhibited reduced inflammatory process and prevented liver necrosis and fibrosis. Immunohistochemical and immunofluorescence analyses of the DEC-treated group showed reduced COX-2, IL1ß, MDA, TGF-ß, and αSMA immunopositivity, besides exhibiting decreased IL1ß, COX-2, NFκB, IFNγ, and TGFß expressions in the western blot analysis. The DEC group enhanced significantly the IL-10 expression. The reduction of hepatic injury in the DEC-treated group was confirmed by the COX-2 and iNOS mRNA expression levels. Based on the results of the present study, DEC can be used as a potential anti-inflammatory drug for chronic hepatic inflammation.