Pyrrolidine Dithiocarbamate Inhibits Nuclear Factor kappaB and Toll-Like Receptor 4 Expression in Rats with Acute Necrotizing Pancreatitis

BACKGROUND/AIMS: To investigate the expression of Toll-like receptor 4 (TLR4) in the pancreases of rats with acute necrotizing pancreatitis (ANP) and any changes upon treatment with pyrrolidine dithiocarbamate (PDTC), an inhibitor of nuclear factor kappaB (NF-kappaB), as well as to determine the relationship between TLR4 and NF-kappaB in ANP pathogenesis. METHODS: A total of 72 SD rats were randomly divided into three groups, namely, the control (sham-operation), ANP, and ANP with PDTC pretreatment groups. The PDTC-pretreated group was intraperitoneally injected with PDTC at a dose of 100 mg/kg 1 hour before the induction of ANP. The expressions of TLR4 and NF-kappaB in pancreatic tissue were evaluated by immunohistochemistry and Western blot analysis. The mRNA levels of cytokines tumor necrosis factor alpha, interleukin (IL)-1beta, and IL-6 were measured by reverse transcription polymerase chain reaction. RESULTS: The expressions of TLR4, NF-kappaB, and cytokine (NF-kappaB target) genes in the pancreatic tissue increased more significantly in the ANP groups than in the sham-operation group at 3, 6, and 12 hours. Pretreatment with PDTC alleviated the inflammatory activation in the pancreas with ANP, causing a significant decrease in the expressions of TLR4, NF-kappaB, and cytokine genes in the pancreatic tissue. CONCLUSIONS: The expressions of TLR4 and NF-kappaB were increased in the pancreases of rats with ANP. PDTC not only inhibits NF-kappaB but also suppresses the expression of TLR4 and downregulates the expression of the related cytokine genes.

Pyrrolidine Dithiocarbamate Inhibits Nuclear Factor kappaB and Toll-Like Receptor 4 Expression in Rats with Acute Necrotizing Pancreatitis

BACKGROUND/AIMS: To investigate the expression of Toll-like receptor 4 (TLR4) in the pancreases of rats with acute necrotizing pancreatitis (ANP) and any changes upon treatment with pyrrolidine dithiocarbamate (PDTC), an inhibitor of nuclear factor kappaB (NF-kappaB), as well as to determine the relationship between TLR4 and NF-kappaB in ANP pathogenesis. METHODS: A total of 72 SD rats were randomly divided into three groups, namely, the control (sham-operation), ANP, and ANP with PDTC pretreatment groups. The PDTC-pretreated group was intraperitoneally injected with PDTC at a dose of 100 mg/kg 1 hour before the induction of ANP. The expressions of TLR4 and NF-kappaB in pancreatic tissue were evaluated by immunohistochemistry and Western blot analysis. The mRNA levels of cytokines tumor necrosis factor alpha, interleukin (IL)-1beta, and IL-6 were measured by reverse transcription polymerase chain reaction. RESULTS: The expressions of TLR4, NF-kappaB, and cytokine (NF-kappaB target) genes in the pancreatic tissue increased more significantly in the ANP groups than in the sham-operation group at 3, 6, and 12 hours. Pretreatment with PDTC alleviated the inflammatory activation in the pancreas with ANP, causing a significant decrease in the expressions of TLR4, NF-kappaB, and cytokine genes in the pancreatic tissue. CONCLUSIONS: The expressions of TLR4 and NF-kappaB were increased in the pancreases of rats with ANP. PDTC not only inhibits NF-kappaB but also suppresses the expression of TLR4 and downregulates the expression of the related cytokine genes.

Inhibition of NF-kappaB prevents high glucose-induced proliferation and plasminogen activator inhibitor-1 expression in vascular smooth muscle cells

Recent epidemiologic studies clearly showed that early intensive glucose control has a legacy effect for preventing diabetic macrovascular complications. However, the cellular and molecular processes by which high glucose leads to macrovascular complications are poorly understood. Vascular smooth muscle cell (VSMC) dysfunction due to high glucose is a characteristic of diabetic vascular complications. Activation of nuclear factor-kappaB (NF-kappaB) may play a key role in the regulation of inflammation and proliferation of VSMCs. We examined whether VSMC proliferation and plasminogen activator inhibitor-1 (PAI-1) expression induced by high glucose were mediated by NF-kappaB activation. Also, we determined whether selective inhibition of NF-kappaB would inhibit proliferation and PAI-1 expression in VSMCs. VSMCs of the aorta of male SD rats were treated with various concentrations of glucose (5.6, 11.1, 16.7, and 22.2 mM) with or without an inhibitor of NF-kappaB or expression of a recombinant adenovirus vector encoding an IkappaB-alpha mutant (Ad-IkappaBalphaM). VSMC proliferation was examined using an MTT assay. PAI-1 expression was assayed by real-time PCR and PAI-1 protein in the media was measured by ELISA. NF-kappaB activation was determined by immunohistochemical staining, NF-kappaB reporter assay, and immunoblotting. We found that glucose stimulated VSMC proliferation and PAI-1 expression in a dose-dependent manner up to 22.2 mM. High glucose (22.2 mM) alone induced an increase in NF-kappaB activity. Treatment with inhibitors of NF-kappaB such as MG132, PDTC or expression of Ad-IkappaB-alphaM in VSMCs prevented VSMC proliferation and PAI-1 expression induced by high glucose. In conclusion, inhibition of NF-kappaB activity prevented high glucose-induced VSMC proliferation and PAI-1 expression.

Increased expression of p38 mitogen- activated protein kinase is related to the acute renal lesions induced by gentamicin

Mitogen-activated protein kinases (MAPK) may be involved in the pathogenesis of acute renal failure. This study investigated the expression of p-p38 MAPK and nuclear factor kappa B (NF-kappaB) in the renal cortex of rats treated with gentamicin. Twenty rats were injected with gentamicin, 40 mg/kg, im, twice a day for 9 days, 20 with gentamicin + pyrrolidine dithiocarbamate (PDTC, an NF-kappaB inhibitor), 14 with 0.15 M NaCl, im, twice a day for 9 days, and 14 with 0.15 M NaCl , im, twice a day for 9 days and PDTC, 50 mg kg-1 day-1, ip, twice a day for 15 days. The animals were killed 5 and 30 days after the last of the injections and the kidneys were removed for histological, immunohistochemical and Western blot analysis and for nitrate determination. The results of the immunohistochemical study were evaluated by counting the p-p38 MAPK-positive cells per area of renal cortex measuring 0.05 mm². Creatinine was measured by the Jaffé method in blood samples collected 5 and 30 days after the end of the treatments. Gentamicin-treated rats presented a transitory increase in plasma creatinine levels. In addition, animals killed 5 days after the end of gentamicin treatment presented acute tubular necrosis and increased nitrate levels in the renal cortex. Increased expression of p-p38 MAPK and NF-kappaB was also observed in the kidneys from these animals. The animals killed 30 days after gentamicin treatment showed residual areas of interstitial fibrosis in the renal cortex, although the expression of p-p38 MAPK in their kidneys did not differ from control. Treatment with PDTC reduced the functional and structural changes induced by gentamicin as well as the expression of p-p38 MAPK and NF-kappaB. The increased expression of p-p38 MAPK and NF-kappaB observed in these rats suggests that these signaling molecules may be involved in the pathogenesis of tubulointerstitial nephritis induced by gentamicin.

Corn silk induces nitric oxide synthase in murine macrophages

Corn silk has been purified as an anticoagulant previously and the active component is a polysaccharide with a molecular mass of 135 kDa. It activates murine macrophages to induce nitric oxide synthase (NOS) and generate substantial amounts of NO in time and dose-dependent manners. It was detectable first at 15 h after stimulation by corn silk, peaked at 24 h, and undetectable by 48 h. Induction of NOS is inhibited by pyrolidine dithiocarbamate (PDTC) and genistein, an inhibitor of nuclear factor kappa B (NF-kappaB) and tyrosine kinase, respectively, indicating that iNOS stimulated by corn silk is associated with tyrosine kinase and NF-kappaB signaling pathways. IkappaB-alpha degradation was detectible at 10 min, and the level was restored at 120 min after treatment of corn silk. Corn silk induced nuclear translocation of NF-kappaB by phosphorylation and degradation of IkappaB-alpha.

Influence of metham sodium on suppression of collar rot disease of peanut, in vitro antibiosis, siderophore production and root colonization by a fluorescent pseudomonad strain FPO4.

A hydroxamate type siderophore producing fluorescent Pseudomonas strain, isolated from the rhizoplane of paddy root showing plant growth promoting activity, exhibited a decreased in vitro antibiosis, production of siderophore and suppression of collar rot in presence of metham sodium. Use of herbicide had a detrimental effect on the plant growth promoting activity of this organism. The multiple drug resistant mutant strain derived from this rhizobacteria colonized the roots, but the herbicide application had a negative effect on their population. HPLC analysis of the siderophore showed five peaks of which the peak number three confirmed the antifungal activity.

Estudo da atividade antifúngica do tolciclato de sódio "in vitro" em otomicoses

O estudo da atividade antifúngica do tolciclato "in vitro" revelou que 100% dos cultivos de A. niger, A. flavus A. fumigatus, Aspergillus sp. e P. citrinum foram inibidos em CIM iguais ou inferiores a 0,62 microngrama/ml de meio. Os cultivos de C. albicans se desenvolveram em concentraçöes testadas até 10 microngrama da droga. Foram tratados 13 casos de otomicoses por vários agentes, inclusive por C. albicans, com êxito completo. O tolciclato constitui, sem dúvida, uma nova alternativa no tratamento das otomicoses

Susceptibilidad in vitro de dermatofitos, Candida y otros hongos frente a Tolciclato: estudio comparativo de dos inóculos / In vitro susceptibitity of dermatophytes, Candida and other fungi to tolciclate: comparative studies using 2 inocula

Se estudió la actividad de tolciclato frente a dermatofitos, Candida y otros hongos con dos inóculos diferentes. Con el inóculo definido por Negroni los dermatofitos fueron inhibidos en un 100% a una concentración inferior o igual a 2,56 microng/ml. En cambio con el inóculo definido por Bianchi, el 100% de estas cepas fue susceptible a concentraciones inferiores o iguales a 0,08 microns/ml. El 100% de las cepas de C. albicans fueron resistentes a 5,12 microng/ml con ambos inóculos