50 research outputs found
Violacein Extracted from Chromobacterium violaceum Inhibits Plasmodium Growth in Vitro and in Vivo
Violacein is a violet pigment extracted from the gram-negative bacterium Chromobacterium violaceum. It presents bactericidal, tumoricidal, trypanocidal, and antileishmanial activities. We show that micromolar concentrations efficiently killed chloroquine-sensitive and -resistant Plasmodium falciparum strains in vitro; inhibited parasitemia in vivo, even after parasite establishment; and protected Plasmodium chabaudi chabaudi-infected mice from a lethal challenge.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Univ Estadual Campinas, UNICAMP, Dept Parasitol, Inst Biol, BR-13083970 Campinas, SP, BrazilUniv Estadual Campinas, UNICAMP, Dept Microbiol & Imunol, Inst Biol, BR-13083970 Campinas, SP, BrazilUniversidade Federal de São Paulo, UNIFESP, Dept Bioquim, BR-04044020 São Paulo, BrazilCEPEM, IPEPATRO, BR-78900970 Porto Velho, RO, BrazilUniv São Paulo, Dept Parasitol, ICB2, São Paulo, BrazilUniv Estadual Campinas, Dept Fisiol & Biofis, Inst Biol, BR-13083970 Campinas, SP, BrazilUniv Estadual Campinas, Lab Quim Biol, Inst Quim, BR-13083970 Campinas, SP, BrazilUniversidade Federal de São Paulo, UNIFESP, Dept Bioquim, BR-04044020 São Paulo, BrazilFAPESP: 2004/00638-6CNPq: 470587/2006-7Web of Scienc
TWEAK Activates the Non-Canonical NFκB Pathway in Murine Renal Tubular Cells: Modulation of CCL21
TWEAK is a member of the TNF superfamily of cytokines that contribute to kidney tubulointerstitial injury. It has previously been reported that TWEAK induces transient nuclear translocation of RelA and expression of RelA-dependent cytokines in renal tubular cells. Additionally, TWEAK induced long-lasting NFκB activation suggestive of engagement of the non-canonical NFκB pathway. We now explore TWEAK-induced activation of NFκB2 and RelB, as well as expression of CCL21, a T-cell chemotactic factor, in cultured murine tubular epithelial cells and in healthy kidneys in vivo. In cultured tubular cells, TWEAK and TNFα activated different DNA-binding NFκB complexes. TWEAK-induced sustained NFκB activation was associated with NFκB2 p100 processing to p52 via proteasome and nuclear translocation and DNA-binding of p52 and RelB. TWEAK, but not TNFα used as control), induced a delayed increase in CCL21a mRNA (3.5±1.22-fold over control) and CCL21 protein (2.5±0.8-fold over control), which was prevented by inhibition of the proteasome, or siRNA targeting of NIK or RelB, but not by RelA inhibition with parthenolide. A second NFκB2-dependent chemokine, CCL19, was upregulates by TWEAK, but not by TNFα. However, both cytokines promoted chemokine RANTES expression (3-fold mRNA at 24 h). In vivo, TWEAK induced nuclear NFκB2 and RelB translocation and CCL21a mRNA (1.5±0.3-fold over control) and CCL21 protein (1.6±0.5-fold over control) expression in normal kidney. Increased tubular nuclear RelB and tubular CCL21 expression in acute kidney injury were decreased by neutralization (2±0.9 vs 1.3±0.6-fold over healthy control) or deficiency of TWEAK (2±0.9 vs 0.8±0.6-fold over healthy control). Moreover, anti-TWEAK treatment prevented the recruitment of T cells to the kidney in this model (4.1±1.4 vs 1.8±1-fold over healthy control). Our results thus identify TWEAK as a regulator of non-canonical NFκB activation and CCL21 expression in tubular cells thus promoting lymphocyte recruitment to the kidney during acute injury
Somatostatin Receptor Splicing Variant sst5TMD4 Overexpression in Glioblastoma Is Associated with Poor Survival, Increased Aggressiveness Features and Somatostatin Analogs Resistance
Glioblastoma (GBM) is the most malignant and lethal brain tumor. Current standard treatment consists of surgery followed by radiotherapy/chemotherapy; however, this is only a palliative approach with a mean post-operative survival of scarcely ~12–15 months. Thus, the identification of novel therapeutic targets to treat this devastating pathology is urgently needed. In this context, the truncated splicing variant of the somatostatin receptor subtype 5 (sst5TMD4), which is produced by aberrant alternative splicing, has been demonstrated to be overexpressed and associated with increased aggressiveness features in several tumors. However, the presence, functional role, and associated molecular mechanisms of sst5TMD4 in GBM have not been yet explored. Therefore, we performed a comprehensive analysis to characterize the expression and pathophysiological role of sst5TMD4 in human GBM. sst5TMD4 was significantly overexpressed (at mRNA and protein levels) in human GBM tissue compared to non-tumor (control) brain tissue. Remarkably, sst5TMD4 expression was significantly associated with poor overall survival and recurrent tumors in GBM patients. Moreover, in vitro sst5TMD4 overexpression (by specific plasmid) increased, whereas sst5TMD4 silencing (by specific siRNA) decreased, key malignant features (i.e., proliferation and migration capacity) of GBM cells (U-87 MG/U-118 MG models). Furthermore, sst5TMD4 overexpression in GBM cells altered the activity of multiple key signaling pathways associated with tumor aggressiveness/progression (AKT/JAK-STAT/NF-κB/TGF-β), and its silencing sensitized GBM cells to the antitumor effect of pasireotide (a somatostatin analog). Altogether, these results demonstrate that sst5TMD4 is overexpressed and associated with enhanced malignancy features in human GBMs and reveal its potential utility as a novel diagnostic/prognostic biomarker and putative therapeutic target in GBMs
A Somatostatin Receptor Subtype-3 (SST3) Peptide Agonist Shows Antitumor Effects in Experimental Models of Nonfunctioning Pituitary Tumors
[Purpose] Somatostatin analogues (SSA) are efficacious and safe treatments for a variety of neuroendocrine tumors, especially pituitary neuroendocrine tumors (PitNET). Their therapeutic effects are mainly mediated by somatostatin receptors SST2 and SST5. Most SSAs, such as octreotide/lanreotide/pasireotide, are either nonselective or activate mainly SST2. However, nonfunctioning pituitary tumors (NFPTs), the most common PitNET type, mainly express SST3 and finding peptides that activate this particular somatostatin receptor has been very challenging. Therefore, the main objective of this study was to identify SST3-agonists and characterize their effects on experimental NFPT models.[Experimental Design] Binding to SSTs and cAMP level determinations were used to screen a peptide library and identify SST3-agonists. Key functional parameters (cell viability/caspase activity/chromogranin-A secretion/mRNA expression/intracellular signaling pathways) were assessed on NFPT primary cell cultures in response to SST3-agonists. Tumor growth was assessed in a preclinical PitNET mouse model treated with a SST3-agonist.
[Results] We successfully identified the first SST3-agonist peptides. SST3-agonists lowered cell viability and chromogranin-A secretion, increased apoptosis in vitro, and reduced tumor growth in a preclinical PitNET model. As expected, inhibition of cell viability in response to SST3-agonists defined two NFPT populations: responsive and unresponsive, wherein responsive NFPTs expressed more SST3 than unresponsive NFPTs and exhibited a profound reduction of MAPK, PI3K-AKT/mTOR, and JAK/STAT signaling pathways upon SST3-agonist treatments. Concurrently, SSTR3 silencing increased cell viability in a subset of NFPTs.
[Conclusions] This study demonstrates that SST3-agonists activate signaling mechanisms that reduce NFPT cell viability and inhibit pituitary tumor growth in experimental models that expresses SST3, suggesting that targeting this receptor could be an efficacious treatment for NFPTs.This work has been funded by the following grants: Junta de Andalucía [CTS-1406 (R.M. Luque), BIO-0139 (J.P. Castaño)]; Ministerio de Ciencia, Innovación y Universidades [BFU2016-80360-R (J.P. Castaño)] and Instituto de Salud Carlos III, co-funded by European Union [ERDF/ESF, “Investing in your future”: PI16/00264 (R.M. Luque), CP15/00156 (M.D. Gahete) and CIBERobn]. CIBER is an initiative of Instituto de Salud Carlos III
Different hydrogen-bonded structures in three 2-thienyl-substituted tetrahydro-1,4-epoxy-1-benzazepines
The molecules of (2RS,4SR)-2-exo-(5-bromo-2-thienyl)-7-chloro-2,3,4,5-tetrahydro-1H-1,4-epoxy-1-benzazepine, C14H11BrClNOS, (I), are linked into cyclic centrosymmetric dimers by C—H⋯π(thienyl) hydrogen bonds. Each such dimer makes rather short Br⋯Br contacts with two other dimers. In (2RS,4SR)-2-exo-(5-methyl-2-thienyl)-2,3,4,5-tetrahydro-1H-1,4-epoxy-1-benzazepine, C15H15NOS, (II), a combination of C—H⋯O and C—H⋯π(thienyl) hydrogen bonds links the molecules into chains of rings. A more complex chain of rings is formed in (2RS,4SR)-7-chloro-2-exo-(5-methyl-2-thienyl)-2,3,4,5-tetrahydro-1H-1,4-epoxy-1-benzazepine, C15H14ClNOS, (III), built from a combination of two independent C—H⋯O hydrogen bonds, one C—H⋯π(arene) hydrogen bond and one C—H⋯π(thienyl) hydrogen bond
Cribado neonatal de hipoacusia en el área de salud de Zamora. Experiencia de 7 años
[ES] Introducción y objetivos: Nuestro objetivo es revisar el programa de cribado universal de hipoacusia
realizado en nuestro Hospital desde 2003, su aceptación y cumplimiento, sus resultados así como
establecer sus posibles puntos de mejora y actualización. Métodos: Durante los años 2003 y 2004 se
realizó cribado universal de los recién nacidos (RN) en nuestro Hospital con etoemisiones acústicas y
realización de potenciales auditivos a aquellos niños con factores de riesgo o que no superasen la
primera fase. Desde 2005 se instaura un programa de cribado universal con potenciales auditivos
automatizados. Resultados: La cobertura del cribado osciló entre el 97,7 % del año 2003 y el 99,4 % de
2009. La primera causa de no realización del cribado es el traslado a otro Hospital. La primera prueba
de cribado se realiza antes del alta a menos del 95 % de los RN pero la segunda prueba antes de los 2
meses cerca del 100%. Pasan a diagnóstico entre un 0,1 % y 0,2 % de los RN. Se han diagnosticado 3
casos de hipoacusia. Conclusiones: Destacamos la cobertura del programa siempre mayor del 95% y su
rechazo menor del 1%. La realización del 5% de primeras pruebas después del alta no repercute en el
diagnóstico precoz, con segunda prueba antes del 2º mes y derivación antes del tercero. Resaltamos el
bajo porcentaje de niños derivados a diagnóstico y de hipoacusias confirmadas, que creemos debido al
traslado neonatal al Hospital terciario de los pacientes de mayor riesgo de hipoacusia.
[EN] Introduction and objectives: Our aim is to check the program of sifted universally of hearing loss
realized in our Hospital from 2003, its acceptance and fulfillment, its results as well as to establish its
possible points of improvement and update. Methods: During the year 2003 and 2004 there was
realized sifted universally of the newborn children (NB) in our Hospital with evoked otoacustic
emissions and accomplishment of auditory potentials to those children with factors of risk or whose
were not overcoming the first phase. From 2005 a program is restored of sifted universally by auditory
automated potentials. Results: The coverage of the sifted one ranges between 97,7 % of the year 2003
and 99,4 % of 2009. The first reason of not accomplishment of the sifted one was the movement to
another Hospital. The first test of sifted was realized before the discharge to less than 95 % of the
newborns but the second test before 2 months near 100 %. They go on to diagnosis among 0,1 % and
0,2 % of the RN. 3 cases have been diagnosed of hearing loss. Conclusions: We distinguish the coverage
of the program always major from 95 % and his minor rejection of 1 %. The accomplishment of 5 % of
the first tests after the discharge does not reverberate in the precocious diagnosis, with the second test
before 2 º month and derivation before the third one. We highlight the low percentage of children
derived to diagnosis and of hearing loss confirmed, that we believe due to the movement neonatal to
the tertiary Hospital of the patients of major risk of hearing loss
Three tetrahydro-1,4-epoxy-1-benzazepines carrying pendent heterocyclic substituents: supramolecular structures in zero, one or two dimensions
(2SR,4RS)-7-Fluoro-2-exo-(2-furyl)-2,3,4,5-tetrahydro-1H-1,4- epoxy-1-benzazepine, C14H12FNO2, (I), crystallizes with Z' = 2 in the space group P2(1)/c. A combination of three C-H center dot center dot center dot O hydrogen bonds and one C-H center dot center dot center dot N hydrogen bond links the molecules into a complex chain of rings, and pairs of such chains are linked into a tube-like structure by two C-H center dot center dot center dot pi(arene) hydrogen bonds. There are no hydrogen bonds in the structure of racemic (2SR,4RS)-2-exo-(5-bromo-2-thienyl)- 7-fluoro-2,3,4,5-tetrahydro-1H-1,4-epoxy-1-benzazepine, C14H11BrFNOS, (II), while the molecules of (2S,4R)-2-exo- (5-bromo-2-thienyl)-7-trifluoromethoxy-2,3,4,5-tetrahydro-1H- 1,4-epoxy-1-benzazepine, C15H14BrF3NO2S, (III), are linked into sheets by a combination of two C-H center dot center dot center dot O hydrogen bonds and one C-H center dot center dot center dot pi(arene) hydrogen bond. The significance of this study lies in its observation of the wide variation in the patterns of supramolecular aggregation, consequent upon modest changes in the peripheral substituents.</p
Cribado neonatal de hipoacusia en el area de salud de Zamora. Experiencia de 7 años
Introduction and objectives: Our aim is to check the program of sifted universally of hearing loss
realized in our Hospital from 2003, its acceptance and fulfillment, its results as well as to establish its
possible points of improvement and update. Methods: During the year 2003 and 2004 there was
realized sifted universally of the newborn children (NB) in our Hospital with evoked otoacustic
emissions and accomplishment of auditory potentials to those children with factors of risk or whose
were not overcoming the first phase. From 2005 a program is restored of sifted universally by auditory
automated potentials. Results: The coverage of the sifted one ranges between 97,7 % of the year 2003
and 99,4 % of 2009. The first reason of not accomplishment of the sifted one was the movement to
another Hospital. The first test of sifted was realized before the discharge to less than 95 % of the
newborns but the second test before 2 months near 100 %. They go on to diagnosis among 0,1 % and
0,2 % of the RN. 3 cases have been diagnosed of hearing loss. Conclusions: We distinguish the coverage
of the program always major from 95 % and his minor rejection of 1 %. The accomplishment of 5 % of
the first tests after the discharge does not reverberate in the precocious diagnosis, with the second test
before 2 º month and derivation before the third one. We highlight the low percentage of children
derived to diagnosis and of hearing loss confirmed, that we believe due to the movement neonatal to
the tertiary Hospital of the patients of major risk of hearing loss.Introducción y objetivos: Nuestro objetivo es revisar el programa de cribado universal de hipoacusia
realizado en nuestro Hospital desde 2003, su aceptación y cumplimiento, sus resultados así como
establecer sus posibles puntos de mejora y actualización. Métodos: Durante los años 2003 y 2004 se
realizó cribado universal de los recién nacidos (RN) en nuestro Hospital con etoemisiones acústicas y
realización de potenciales auditivos a aquellos niños con factores de riesgo o que no superasen la
primera fase. Desde 2005 se instaura un programa de cribado universal con potenciales auditivos
automatizados. Resultados: La cobertura del cribado osciló entre el 97,7 % del año 2003 y el 99,4 % de
2009. La primera causa de no realización del cribado es el traslado a otro Hospital. La primera prueba
de cribado se realiza antes del alta a menos del 95 % de los RN pero la segunda prueba antes de los 2
meses cerca del 100%. Pasan a diagnóstico entre un 0,1 % y 0,2 % de los RN. Se han diagnosticado 3
casos de hipoacusia. Conclusiones: Destacamos la cobertura del programa siempre mayor del 95% y su
rechazo menor del 1%. La realización del 5% de primeras pruebas después del alta no repercute en el
diagnóstico precoz, con segunda prueba antes del 2º mes y derivación antes del tercero. Resaltamos el
bajo porcentaje de niños derivados a diagnóstico y de hipoacusias confirmadas, que creemos debido al
traslado neonatal al Hospital terciario de los pacientes de mayor riesgo de hipoacusia