Effects of thymoquinone and curcumin on the regeneration of rat livers subject to 70% hepatectomy

Abstract Purpose: To investigate thymoquinone, curcumin and a combination of these two drugs were effective or not at the growth of liver. Methods: Forty female Wistar-Albino rats distributed into five groups of eight rats each, control, thymoquinone, curcumin, and thymoquinone/curcumin groups. Pathological specimens were studied using the Ki-67 Proliferation Index(PI); and arginase(Arg), tissue plasminogen activator(tPA), ceruloplasmin(Cer) and nitric oxide(NO) were studied in biochemical analysis. Results: Our results showed that Ki-67 proliferation index was low in Groups 1. The proliferation coefficient was significantly higher in the Group 2 and Group 4 than in the Group 1 and Group 3.(P < 0.001 between Groups 1 and 2, 1 and 4, and 3 and 4). There was no difference between Groups 2 and 4 (P = 1). The results of the biochemical Arg, tPA and Cer test showed statistically between the Group 1 and Group 2. NO showed significant differences Group 1 and 3. Conclusions: Thymoquinone and curcumin both have known positive effects on the organism. Histological and biochemical tests showed that thymoquinone is more effective than curcumin.

Arginase activity and nitric oxide levels in patients with obstructive sleep apnea syndrome

OBJECTIVE: Obstructive sleep apnea syndrome is characterized by repetitive obstruction of the upper airways, and it is a risk factor for cardiovascular diseases. There have been several studies demonstrating low levels of nitric oxide in patients with obstructive sleep apnea syndrome compared with healthy controls. In this study, we hypothesized that reduced nitric oxide levels would result in high arginase activity. Arginase reacts with L-arginine and produces urea and L-ornithine, whereas L-arginine is a substrate for nitric oxide synthase, which produces nitric oxide. METHODS: The study group consisted of 51 obstructive sleep apnea syndrome patients (M/F: 43/8; mean age 49±10 years of age) and 15 healthy control subjects (M/F: 13/3; mean age 46±14 years of age). Obstructive sleep apnea syndrome patients were divided into two subgroups based on the presence or absence of cardiovascular disease. Nitric oxide levels and arginase activity were measured via an enzyme-linked immunosorbent assay of serum samples. RESULTS: Serum nitric oxide levels in the control subjects were higher than in the obstructive sleep apnea patients with and without cardiovascular diseases (p<0.05). Arginase activity was significantly higher (p<0.01) in obstructive sleep apnea syndrome patients without cardiovascular diseases compared with the control group. Obstructive sleep apnea syndrome patients with cardiovascular diseases had higher arginase activity than the controls (p<0.001) and the obstructive sleep apnea syndrome patients without cardiovascular diseases (p<0.05). CONCLUSION: Low nitric oxide levels are associated with high arginase activity. The mechanism of nitric oxide depletion in sleep apnea patients suggests that increased arginase activity might reduce the substrate availability of nitric oxide synthase and thus could reduce nitric oxide levels. .

Aspectos imunopatogênicos da leishmaniose cutânea difusa: fatores da leishmania e do hospedeiro / Immunopathogenic aspects of diffuse cutaneous leishmaniasis: Leishmania factors and host

A progressão crônica da LCD é atribuída à falta da imunidade mediada por células específica para antígeno de Leishmania e predominância de uma resposta do tipo Th2. Neste sentido, tanto fatores do parasita quanto do hospedeiro podem atuar na desativação da resposta imune favorecendo a replicação da Leishmania. Inicialmente avaliamos o papel da exposição de fosfatidilserina na infecção de macrófagos murinos com Leishmania amazonensis isolados de pacientes com LCD. Para isso, macrófagos peritoneais de camundongos F1(BALB/c x C57BL/6) foram infectados com os diferentes isolados obtidos de pacientes com LCD e LCL. Os isolados obtidos de pacientes com LCD apresentaram maior expressão de PS do que os isolados de pacientes com LCL após 24 horas de infecção. Em seguida, avaliamos a infectividade dos diferentes isolados. As amastigotas de pacientes com LCD apresentaram maior porcentagem de macrófagos infectados e índice de infecção, quando comparados com amastigotas de pacientes com LCL. Quanto ao mecanismo, o grupo infectado com os isolados de pacientes com LCD apresentou um aumento na relação TGF-β/TNF-α e IL-10/TNF-α em relação ao grupo LCL. A análise de correlação revelou que a porcentagem de macrófagos infectados, o índice de infecção, os índices de TGF-β/TNF-α e IL-10/TNF-α, bem como o tamanho dos vacúolos estão diretamente associados a maior exposição de PS. Além disso, o número de lesões e o tempo de doença dos pacientes com LCD também estão associados á exposição de PS. O reconhecimento de PS tem como consequência a produção de TGF, IL-10, IL-4 e PGE2, que ativam a via da enzima arginase e consequentemente a produção de poliaminas. Por isso buscamos investigar a participação de tais mediadores em pacientes com LCD. Os níveis da arginase I, ODC e TGF-β no plasma de pacientes com LCD estava elevados quando comparado com os pacientes com LCL ou o controle saudável da área endêmica. Por outro lado, os níveis de TNF-α, IL-12, MCP-1 e CXCL-10 estavam reduzidos no plasma de pacientes com LCD comparado aos pacientes com LCL. Os níveis de arginase apresentaram correlação positiva com ODC, TGF-β e PGE e correlação negativa com TNF-α, IL-12, MCP-1 e CXCL-10. A produção da arginase e ODC também foi avaliada nas lesões dos pacientes através de imunohistoquímica. As lesões dos pacientes com LCD apresentaram uma marcação mais intensa e difusa do que as de LCL. Além disso, a expressão da cicloxigenase 2 também estava aumentada nas lesões de LCD. A expressão do mRNA das enzimas fosfolipase A2, COX-2, prostaglandina sintase, espermina e espermidina sintase apresentaram uma relação positiva com a enzima arginase, indicando que esta interfere diretamente no metabolismo dos mediadores lipídicos e na via de síntese das poliaminas. A inibição das enzimas arginase e ODC com nor-NOHA e DFMO, respectivamente, reduziu a carga parasitária de macrófagos humanos infectados com L. amazonensis após 72 h de infecção. Além disso, os inibidores reduziram a produção de TGF e PGE2 no sobrenadante das culturas. Em conjunto, nossos dados sugerem que a liberação local e sistêmica de prostaglandinas e poliaminas associadas à via da arginase em pacientes com LCD deve estar associada com a inabilidade em montar uma resposta imune eficiente contra a infecção por Leishmania proporcionando um ambiente favorável para a replicação do parasita e disseminação da doença. Nossos resultados mostram também que este ambiente imunossuprimido pode ser induzido pela exposição de PS na superfície de L. amazonensis deflagrando uma resposta anti-inflamatória nos pacientes com LCD.

[Application of a new method for arginase as a liver function test in dogs]

Arginase catalyzes the conversion of arginine to urea and omithine in the liver of urectelic animals. Higher activity of this enzyme has been detected in the sera of patients with hepatic diseases. Many difficulties inherent in current methods for arginase have hamperd wide use of this enzyme as a liver function test. A new colorimetric method for determination of arginase has been developed in this laboratory. This method is based on the determination of remaining arginine, after its conversion, by reaction with p-nitrophenyl glyoxal [PNPG] at pH 9.0 to produce a color which absorbs maximally at 480 nm. The decrease in the absorbance in the presence of arginase is correlated with the enzyme activity. This method was used to measure the level of arginase in the sera of dogs in which liver necrosis had been experimentally induced by oral administration of carbon terrachoride. The results indicate that PNPG can be used as a reliable method for determination of arginase and might be applied in parallel with other enzymes that are currently used for liver function test

Lymphocyte arginase activity in leprosy--a preliminary report.

Arginase activity was estimated in serum and lymphocytes of 22 healthy controls and 50 untreated leprosy patients across the spectrum. The patients included 21 lepromatous/borderline lepromatous (LL/BL); 20 borderline borderline/borderline tuberculoid (BB/BT) and 9 tuberculoid (TT) cases. Mean serum arginase levels were 1.51 +/- 0.43, 1.41 +/- 0.43, 1.24 +/- 0.43 and 1.10 +/- 0.026 mu moles/min/ml in LL/BL, BB/BT and TT patients and healthy controls respectively. The lymphocyte arginase activity showed a similar increasing trend from TT to LL/BL. The mean lymphocyte arginase levels were 0.87 +/- 0.31 mu moles/min/10(6) cells in healthy controls and 1.81 +/- 0.40, 2.54 +/- 0.60 and 5.48 +/- 0.56 mu moles/min/10(6) cells in TT, BB/BT and LL/BL patients respectively. The increasing trend specially in lymphocyte arginase levels across the spectrum of leprosy correlated with the degree of impairment in the protective cell mediated immune response and also the extent of disease. The role of these pathophysiological alterations in relation to defect in immune response calls for investigation.