Liver expression of IL-22, IL-22R1 and IL-22BP in patients with chronic hepatitis C with different fibrosis stages.

AIMS: Liver fibrosis is the result of an exacerbated wound-healing response associated with chronic liver injury. Interleukin-22 (IL-22) plays a key role in liver disease, through either a protective or an adverse role, depending on the context. The relationship between IL-22 and its receptors IL-22R1 and IL-22BP (soluble inhibitor) in liver fibrosis is unknown. In this study, we assessed the presence and quantity of IL-22, IL-22R1, and IL-22BP-producing cells in liver tissues of patients with chronic hepatitis C. METHODS AND RESULTS: The number of IL-22-producing cells was significantly higher in stages F1, F2, and F3 when compared to F0 or F4 (p < 0.05). The immunostaining of IL-22R1 decreased as liver fibrosis increased from F1 to F4. On the other hand, the concentration of IL-22BP-producing cells was higher in patients with cirrhosis (F4). Furthermore, the IL-22BP:IL-22 ratio was highest in patients with cirrhosis. CONCLUSIONS: Our results suggest that IL-22, IL-22R1 and IL-22BP may be involved in the mechanisms of liver fibrosis in patients with chronic hepatitis C.

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.

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.

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.

Involvement of AMPK, IKßα-NFκB and eNOS in the sildenafil anti-inflammatory mechanism in a demyelination model.

Sildenafil (Viagra®) has recently been found to have a neuroprotective effect, which occurs through the inhibition of inflammation and demyelination in the cerebellum. However, the mechanism of action of sildenafil remains unknown. AMPK, the regulatory protein of the lipid and glucose metabolism, plays a protective role by activating the eNOS enzyme. The production of a nanomolar concentration of NO by eNOS has an anti-inflammatory effect through the cGMP signaling pathway and plays an important role in the regulation of the nuclear transcription factor (NFkB), preventing the expression of inflammatory genes. The present study investigated whether AMPK-eNOS-NO-cGMP-IКßα-NFkB is involved in the mechanism of action of sildenafil in a cuprizone-demyelination model. Neuroinflammation and demyelination induced by cuprizone in rodents have been widely used as a model of MS. In the present study, five male C57BL/6 mice (7-10 weeks old) were used. Over a four week period, the groups received: cuprizone (CPZ) 0.2% mixed in feed; CPZ in the diet, combined with the administration of sildenafil (Viagra®, Pfizer, 25mg/kg) orally in drinking water, starting concurrently (sild-T0) or 15 days (sild-T15) after the start of CPZ. Control animals received pure food and water. The cerebella of the mice were dissected and processed for immunohistochemistry, immunofluorescence (frozen), western blotting and dosage of cytokines (Elisa). CPZ induced an increase in the expression of GFAP, IL-1ß TNF-α, total NFkB and inactive AMPK, and prompt microglia activation. CPZ also induced a reduction of IKßα. The administration of sildenafil reduced the expression of the pro-inflammatory cytokines IL-1ß and TNF-α and increased the expression of the anti-inflammatory cytokine IL-10. In addition, the administration of sildenafil reduced expression of GFAP, NFkB, inactive AMPK and iNOS, and increased IKßα. Interestingly, sildenafil also reduced levels of NGF. In general, the sild-T0 group was more effective than sild-T15 in improving clinical status and promoting the control of neuroinflammation. The present study offers evidence that sildenafil has anti-inflammatory and neuroprotective effects, which are probably achieved through modulation of AMPK-IKßα-NFκB signaling. In addition, eNOS may play a role in the sildenafil neuroprotective mechanism, contributing to the activation of AMPK. However, other pathways such as MAPK-NFkB and the downstream proteins AMPK (AMPK-SIRT1-NFκB) should also be further investigated. An understanding of these mechanisms of action is critical for the clinical use of sildenafil to control neuroinflammation in neurodegenerative diseases such as MS.

Chronic treatment with Sildenafil has no effect on folliculogenesis or fertility in C57BL/6 and C57BL/6 knockout for iNOS mice.

Sildenafil is an important phosphodiesterase inhibitor used to treat a range of diseases, including cardiovascular disease, prostatic hyperplasia and pulmonary hypertension. Its main mechanism of action is the inhibition of phosphodiesterase 5, leading to increased intracellular cyclic guanosine 3',5'-monophosphate. This second messenger plays an interesting role in the reproductive tract. The aim of the present study was to evaluate the effect of Sildenafil on folliculogenesis and fertility in mice. To do so, C57BL/6 wild-type mice and inducible nitric oxide synthase knockout (iNOS(-/-)) mice were treated with Sildenafil, and reproductive variables were evaluated. The treated and control animals underwent estrous cycle and fertility assay. Lipid profile, serum nitric oxide levels and the expression of endothelial nitric oxide synthase, inducible nitric oxide synthase and guanylate cyclase were evaluated. Additionally, ovaries were submitted to histological and morphological analysis. The findings demonstrated that chronic treatment with Sildenafil had no effect on folliculogenesis or fertility in C57BL/6 mice, suggesting that this drug can be safely used by women of childbearing age.

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.

Effect of chronic Sildenafil treatment on the prostate of C57Bl/6 mice.

Sildenafil is a potent and selective inhibitor of phosphodiesterase-5 (PDE5) and is considered first-line therapy for erectile dysfunction. Nowadays, Sildenafil is used extensively throughout the world on patients with pulmonary hypertension. However, few studies have evaluated the possible side effects of chronic Sildenafil treatment on the male reproductive system, specifically in the prostate. In the present study, it was demonstrated via morphological and ultrastructural analysis that chronic treatment with Sildenafil induced an enhancement of the glandular activity of the prostate. In addition, mice treated with Sildenafil showed a significant increase in testosterone serum levels. However, no statistically significant differences were observed in nitric oxide serum levels, or in sGC, eNOS, PSA and TGF-ß prostatic expression. In conclusion, the present study suggests that chronic use of Sildenafil does not cause evident prostatic damage, and therefore, can be used pharmacologically to treat a variety of disorders.

Diethylcarbamazine inhibits NF-κB activation in acute lung injury induced by carrageenan in mice.

Diethylcarbamazine citrate (DEC) is widely used to treat lymphatic filariasis and Tropical Pulmonary Eosinophilia. A number of studies have reported a possible role in the host immune system, but exactly how DEC exerts this effect is still unknown. The present study reports the effects of DEC pretreatment on NF-κB regulation using the pleurisy model induced by carrageenan. Swiss male mice (Mus musculus) were divided into four experimental groups: control (SAL); carrageenan (CAR); diethylcarbamazine (DEC) and curcumin (CUR). The animals were pretreated with DEC (50mg/kg, v.o), CUR (50mg/kg, i.p) or distilled water for three consecutive days before pleurisy. One way analysis of variance (ANOVA) was performed by Tukey post-hoc test, and values were considered statistically significant when p<0.05. DEC pretreatment reduced tissue damage and the production of inflammatory markers, such as NO, iNOS, PGE2, COX-2, and PARP induced by carrageenan. Similarly, a known inhibitor of NF-κB pathway (curcumin) was also able to reduce these parameters. Like curcumin, DEC prevents NF-κB activation by reducing NF-κB p65 phosphorylation and IκBα degradation. DEC prevented NF-κB activation via p38 MAPK, but did not interfere in the ERK pathway in this experimental model. However, further studies should be developed to confirm this hypothesis. These findings suggest that DEC could be a promising drug for inflammatory disorders, especially in pulmonary diseases such as Acute Lung Inflammation, due its high anti-inflammatory potential which prevents NF-κB activation.

Inhibition of NF-κB activation by diethylcarbamazine prevents alcohol-induced liver injury in C57BL/6 mice.

Induction of NF-κB-mediated gene expression has been identified in the pathogenesis of alcoholic liver disease (ALD). Diethylcarbamazine (DEC) is a piperazine derivative drug with anti-inflammatory properties. The present study was designed to evaluate the effect of DEC on NF-κB pathways in mice undergoing alcoholism induced hepatic inflammation. Forty male C57BL/6 mice were divided equally into four groups: control group (C); DEC-treated group, which received 50mg/kg (DEC50); alcoholic group (EtOH), submitted to chronic alcohol consumption and the alcohol-DEC treated group (EtOH50), submitted to chronic alcoholism consumption plus DEC treatment. Histological analysis of the alcoholic group showed evident hepatocellular damage which was reduced in EtOH50 group. Immunohistochemistry and western blot results showed elevated expression of inflammatory markers such as MDA, TNF-α, IL-1ß, COX-2 and iNOS in hepatocytes of EtOH group. However, low immunopositivity for these markers was detected following DEC treatment. In the EtOH group the activation of NF-κB was observed by an increase in the expression of both NF-κB and pNF-κB in hepatocytes. This expression was significantly reduced in livers of EtOH50 group. Protein expression of Iκßα was measured to determine whether activation of NF-κB might be the result of Iκßα degradation. It was observed that expression of this protein was low in EtOH group, while animals treated with DEC had a high expression of Iκßα. The results of the present study indicate that DEC alleviates alcoholic liver injury, in part by the inhibiting activation of NF-κB and by suppressing the induction of NF-κB-dependent genes.

Diethylcarbamazine attenuates the development of carrageenan-induced lung injury in mice.

Diethylcarbamazine (DEC) is an antifilarial drug with potent anti-inflammatory properties as a result of its interference with the metabolism of arachidonic acid. The aim of the present study was to evaluate the anti-inflammatory activity of DEC in a mouse model of acute inflammation (carrageenan-induced pleurisy). The injection of carrageenan into the pleural cavity induced the accumulation of fluid containing a large number of polymorphonuclear cells (PMNs) as well as infiltration of PMNs in lung tissues and increased production of nitrite and tumor necrosis factor-α and increased expression of interleukin-1ß, cyclooxygenase (COX-2), and inducible nitric oxide synthase. Carrageenan also induced the expression of nuclear factor-κB. The oral administration of DEC (50 mg/Kg) three days prior to the carrageenan challenge led to a significant reduction in all inflammation markers. The present findings demonstrate that DEC is a potential drug for the treatment of acute lung inflammation.