Hepatoprotective and anti-inflammatory effects of silibinin on experimental preeclampsia induced by 1-NAME in rats

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Chronic ethanol intake promotes double gluthatione S-transferase transforming growth factor-alpha-positive hepatocellular lesions in male Wistar rats

The chronic ethanol intake influence on the gluthatione S-transferase (GST-P) and transforming growth factor alpha (TGF-alpha) expression in remodeling/persistent preneoplastic lesions (PNLs) was evaluated in the resistant hepatocyte model. Male Wistar rats were allocated into five groups: G1, non-treated, fed water and chow ad libitum; G2, non-treated and pair-fed chow (restricted to match that of G3 group) and a maltodextrin (MD) solution in tap water (matched ethanol-derived calories); G3, fed 5% ethanol in drinking water and chow ad libitum; G4, diethylnitrosamine (DEN, 200 mg/kg, body weight) plus 200 parts per million of 2-acetylaminofluorene (2-AAF) for 3 weeks and pair-fed chow (restricted to match that of G5 group) and an MD solution in tap water (matched ethanol-derived calories); G5, DEN/2-AAF treatment, fed ethanol 5% and chow ad libitum. All animals were subjected to 70% partial hepatectomy at week 3 and sacrificed at weeks 12 or 22, respectively. Liver samples were collected for histological analysis or immunohistochemical expression of GST-P, TGF-alpha and proliferating cell nuclear antigen or zymography for matrix metalloproteinases-2 and -9. At the end of ethanol treatment, there was a significant increase in the percentage of liver area occupied by persistent GST-P-positive PNLs, the number of TGF-alpha-positive PNLs and the development of liver tumors in ethanol-fed and DEN/2-AAF-treated groups (G5 versus G4, P < 0.001). In addition, ethanol feeding led to a significant increase in cell proliferation mainly in remodeling and persistent PNLs with immunoreactivity for TGF-alpha at week 22 (P < 0.001). Gelatinase activities were not altered by ethanol treatment. The results demonstrated that ethanol enhances the selective growth of PNL with double expression of TGF-alpha and GST-P markers.

Progesterone concentrations, exogenous equine chorionic gonadotropin, and timing of prostaglandin F-2 alpha treatment affect fertility in postpuberal Nelore heifers

Two experiments were performed to test the hypothesis that elevated progesterone concentrations impair pregnancy rate to timed artificial insemination (TAI) in postpuberal Nelore heifers. In Experiment 1, postpuberal Nelore heifers (n = 398) received 2 mg estradiol benzoate (EB) and either a new progesterone-releasing intravaginal device containing 1.9 g of progesterone (CIDR) (first use) or a CIDR previously used for 9 d (second use) or for 18 d (third use) on Day 0, 12.5 mg prostaglandin F-2 alpha (PGF(2 alpha)) on Day 7, 0.5 mg estradiol cypionate (ECP) and CIDR withdrawal on Day 9, and TAI on Day 11. Largest ovarian follicle diameter was determined on Day 11. The third-use CIDR treatment increased largest ovarian follicle diameter and pregnancy rate. Conception to TAI was reduced in heifers with smaller follicles in the first- and second-use CIDR treatments, but not in the third-use CID treatment. In Experiment 2, postpuberal Nelore heifers received the synchronization treatment described in Experiment 1 or received 12.5 mg PGF2. on Day 9 rather than Day 7. In addition, 50% of heifers received 300 IU equine chorionic gonadotropin (eCG) on Day 9. Heifers were either TAI (Experiment 2a; n = 199) or Al after detection of estrus (Experiment 2b; n = 125 of 202). In Experiment 2a, treatment with cCG increased pregnancy rate to TAI in heifers that received PGF2. on Day 9 but not on Day 7 and in heifers that received a first-use CIDR but not in heifers that received a third-use CIDR. Treatments did not influence reproductive performance in Experiment 2b. In summary, pregnancy rate to TAI in postpuberal Nelore heifers was optimized when lower concentrations of cxogcnous progesterone were administered, and eCG treatment was beneficial in heifers expected to have greater progesterone concentrations. (C) 2009 Elsevier B.V. All rights reserved.

Expression of fibroblast growth factor 10 and its receptor, fibroblast growth factor receptor 2B, in the bovine corpus luteum

There is evidence that several fibroblast growth factors (FGFs) are involved in growth and development of the corpus luteum (CL), but many FGFs have not been investigated in this tissue, including FGF10. The objective of this study was to determine if FGF10 and its receptor (FGFR2B) are expressed in the CL. Bovine CL were collected from an abattoir and classed as corpus hemorrhagica (stage 1), developing (stage 11), developed (stage 111), and regressed (stage IV) CL. Expression of FGF10 and FGFR2B mRNA was measured by reverse transcription-polymerase chain reaction (RT-PCR). Both genes were expressed in bovine CL, and FGF10 expression did not differ between stages of CL development. FGF10 protein was localized to large and small luteal cells by immunohistochemistry. FGFR2B expression was approximately threefold higher in regressed compared to developing and developed CL (P < 0.05). To determine if FGF10 and FGFR2B expression is regulated during functional luteolysis, cattle were injected with PGF2 alpha and CL collected at 0, 0.5, 2, 4, 12, 24, 48, and 64 hr thereafter (n = 5 CL/time point), and mRNA abundance was measured by real-time RT-PCR. FGF10 mRNA expression did not change during functional luteolysis, whereas FGFR2B mRNA abundance decreased significantly at 2, 4, and 12 hr after PGF2a, and returned to pretreatment levels for the period 24-64 hr post-PGF2 alpha. These data suggest a potential role for FGFR2B signaling during structural luteolysis in bovine CL.

MKK3/6-p38 MAPK signaling is required for IL-1 beta and TNF-alpha-induced RANKL expression in bone marrow stromal cells

Coupled bone turnover is directed by the expression of receptor-activated NF-kappa B ligand (RANKL) and its decoy receptor, osteoprotegerin (OPG). Proinflammatory cytokines, such as interleukin-1 beta (IL-1 beta) and tumor necrosis factor-alpha (TNF-alpha) induce RANKL expression in bone marrow stromal cells. Here, we report that IL-1 beta and TNF-alpha-induced RANKL requires p38 mitogen-activating protein kinase (MAPK) pathway activation for maximal expression. Real-time PCR was used to assess the p38 contribution toward IL-1 beta and TNF-alpha-induced RANKL mRNA expression. Steady-state RANKL RNA levels were increased approximately 17-fold by IL-1 beta treatment and subsequently reduced similar to 70%-90% when p38 MAPK was inhibited with SB203580. RANKL mRNA stability data indicated that p38 MAPK did not alter the rate of mRNA decay in IL-1 beta-induced cells. Using a RANKL-luciferase cell line receptor containing a 120-kB segment of the 5' flanking region of the RANKL gene, reporter expression was stimulated 4-5-fold by IL-1 beta or TNF-alpha treatment. IL-1 beta-induced RANKL reporter expression was completely blocked with specific p38 inhibitors as well as dominant negative mutant constructs of MAPK kinase-3 and -6. In addition, blocking p38 signaling in bone marrow stromal cells partially inhibited IL-1 beta and TNF-alpha-induced osteoclastogenesis in vitro. Results from these studies indicate that p38 MAPK is a major signaling pathway involved in IL-1 beta and TNF-alpha-induced RANKL expression in bone marrow stromal cells.

Inhibition of sodium appetite by lipopolysaccharide: involvement of alpha(2)-adrenoceptors

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Immune regulatory effect of pHSP65 DNA therapy in pulmonary tuberculosis: activation of CD8(+) cells, interferon-gamma recovery and reduction of lung injury

A DNA vaccine based on the heat-shock protein 65 Mycobacterium leprae gene (pHSP65) presented a prophylactic and therapeutic effect in an experimental model of tuberculosis. In this paper, we addressed the question of which protective mechanisms are activated in Mycobacterium tuberculosis-infected mice after immune therapy with pHSP65. We evaluated activation of the cellular immune response in the lungs of infected mice 30 days after infection (initiation of immune therapy) and in those of uninfected mice. After 70 days (end of immune therapy), the immune responses of infected untreated mice, infected pHSP65-treated mice and infected pCDNA3-treated mice were also evaluated. Our results show that the most significant effect of pHSP65 was the stimulation of CD8(+) lung cell activation, interferon-gamma recovery and reduction of lung injury. There was also partial restoration of the production of tumour necrosis factor-alpha. Treatment with pcDNA3 vector also induced an immune stimulatory effect. However, only infected pHSP65-treated mice were able to produce significant levels of interferon-gamma and to restrict the growth of bacilli.

Downregulation of nuclear factor-kappa B (NF-kappa B) pathway by silibinin in human monocytes challenged with Paracoccidioides brasiliensis

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Alpha-glucosidase promotes hemozoin formation in a blood-sucking bug: An evolutionary history

Background: Hematophagous insects digest large amounts of host hemoglobin and release heme inside their guts. In Rhodnius prolixus, hemoglobin-derived heme is detoxified by biomineralization, forming hemozoin (Hz). Recently, the involvement of the R. prolixus perimicrovillar membranes in Hz formation was demonstrated. Methodology/Principal Findings: Hz formation activity of an α-glucosidase was investigated. Hz formation was inhibited by specific α-glucosidase inhibitors. Moreover, Hz formation was sensitive to inhibition by Diethypyrocarbonate, suggesting a critical role of histidine residues in enzyme activity. Additionally, a polyclonal antibody raised against a phytophagous insect α-glucosidase was able to inhibit Hz formation. The α-glucosidase inhibitors have had no effects when used 10 h after the start of reaction, suggesting that α-glucosidase should act in the nucleation step of Hz formation. Hz formation was seen to be dependent on the substrate-binding site of enzyme, in a way that maltose, an enzyme substrate, blocks such activity. dsRNA, constructed using the sequence of α-glucosidase gene, was injected into R. prolixus females' hemocoel. Gene silencing was accomplished by reduction of both α-glucosidase and Hz formation activities. Insects were fed on plasma or hemin-enriched plasma and gene expression and activity of α-glucosidase were higher in the plasma plus hemin-fed insects. The deduced amino acid sequence of α-glucosidase shows a high similarity to the insect α-glucosidases, with critical histidine and aspartic residues conserved among the enzymes. Conclusions/Significance: Herein the Hz formation is shown to be associated to an a-glucosidase, the biochemical marker from Hemipteran perimicrovillar membranes. Usually, these enzymes catalyze the hydrolysis of glycosidic bond. The results strongly suggest that α-glucosidase is responsible for Hz nucleation in the R. prolixus midgut, indicating that the plasticity of this enzyme may play an important role in conferring fitness to hemipteran hematophagy, for instance. © 2009 Mury et al.

Qualidade de vida e morbidade psicológica de pacientes portadores de hepatite C em tratamento com interferon peguilado e ribavirina

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Alpha and beta diversity of lepidoptera in eucalyptus plantations in the amazonian region of Brazil

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Interferon-gamma production by human neutrophils upon stimulation by IL-12, IL-15 and IL-18 and challenge with Paracoccidioides brasiliensis

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Lycopene supplementation reduces TNF-alpha via RAGE in the kidney of obese rats

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Atuação do interferon-tau no reconhecimento materno da gestação

Maternal recognition of pregnancy is a process by which the conceptus signals its presence to the mother in order to prolong the life of the corpus luteum (CL) thus maintaining the pregnancy. This process occurs between days 15 and 19 after fertilization and is the most important biological challenge for obtaining satisfactory reproductive indices in bovine. Interferon-tau (IFN-τ) glycoprotein -secreted in the uterus by the conceptus- has a paracrine action inhibiting the expression of estrogen receptors (ESR1) and oxytocin (OXTR) in the endometrium, thus preventing the release of luteolytic pulses of prostaglandin F2 alpha (PGF2α), hormone responsible for the onset of luteolysis. IFN-τ also increases the expression of several interferon-stimulated genes (ISGs) in the uterus, CL, and blood cells. Direct endocrine action of IFN-τ on extrauterine tissues stimulates ISGs expression, which in the corpus luteum seems to be involved with luteal resistance to luteolytic action of PGF2α. This review discusses recent findings on the luteolysis mechanism in the bovine and endocrine and paracrine mechanisms such as IFN-τ during the maternal recognition of pregnancy.

Differential Gene Expression Profiles May Differentiate Responder and Nonresponder Patients with Rheumatoid Arthritis for Methotrexate (MTX) Monotherapy and MTX plus Tumor Necrosis Factor Inhibitor Combined Therapy

Objective. We aimed to evaluate whether the differential gene expression profiles of patients with rheumatoid arthritis (RA) could distinguish responders from nonresponders to methotrexate (MTX) and, in the case of MTX nonresponders, responsiveness to MTX plus anti-tumor necrosis factor-alpha (anti-TNF) combined therapy. Methods. We evaluated 25 patients with RA taking MTX 15-20 mg/week as a monotherapy (8 responders and 17 nonresponders). All MTX nonresponders received intliximab and were reassessed after 20 weeks to evaluate their anti-TNF responsiveness using the European League Against Rheumatism response criteria. A differential gene expression analysis from peripheral blood mononuclear cells was performed in terms of hierarchical gene clustering, and an evaluation of differentially expressed genes was performed using the significance analysis of microarrays program. Results. Hierarchical gene expression clustering discriminated MTX responders from nonresponders, and MTX plus anti-TNF responders from nonresponders. The evaluation of only highly modulated genes (fold change > 1.3 or < 0.7) yielded 5 induced (4 antiapoptotic and CCL4) and 4 repressed (4 proapoptotic) genes in MTX nonresponders compared to responders. In MTX plus anti-TNF nonresponders, the CCL4, CD83, and BCL2A1 genes were induced in relation to responders. Conclusion. Study of the gene expression profiles of RA peripheral blood cells permitted differentiation of responders from nonresponders to MTX and anti-TNF. Several candidate genes in MTX non-responders (CCL4, HTRA2, PRKCD, BCL2A1, CAV1, TNIP1 CASP8AP2, MXD1, and BTG2) and 3 genes in MTX plus anti-TNF nonresponders (CCL4, CD83, and BCL2A1) were identified for further study. (First Release July 1 2012; J Rheumatol 2012;39:1524-32; doi:10.3899/jrheum.120092)