Lipotoxicity-associated inflammation is prevented by guarana (Paullinia cupana) in a model of hyperlipidemia.

Hyperlipidemia causes lipotoxicity which prompts an inflammatory response linked to the development of cardiovascular diseases. Natural compounds have been receiving special attention for its potential to treat diseases, inexpensiveness, and safety. Guarana (Paullinia cupana) has demonstrated notable anti-inflammatory and antioxidant effects, which may prevent chronic diseases caused by changes in lipid profile. Thus, this study aims to evaluate the effect of guarana powder (Paullinia cupana) in the purine metabolism and inflammatory profile in lymphocytes and serum of rats with Poloxamer-407-induced hyperlipidemia. Pretreatment with guarana 12.5, 25, and 50 mg/kg/day or caffeine (0.2 mg/kg/day) by gavage was applied to adult male Wistar rats for a period of 30 days. As a comparative standard, we used simvastatin (0.04 mg/kg) post-induction. Hyperlipidemia was acutely induced with intraperitoneally injection of Poloxamer-407 (500 mg/kg). Guarana powder and caffeine increased the activity of the E-NTPDase (ecto-apyrase), and all pretreatments decreased the E-ADA (ecto-adenosine deaminase) activity, reducing the inflammatory process caused by lipotoxicity. In hyperlipidemic rats, ATP levels were increased while adenosine levels were decreased, guarana and caffeine reverted these changes. Guarana powder, caffeine, and simvastatin also prevented the increase in INF-γ and potentiated the increase in IL-4 levels, promoting an anti-inflammatory profile. Guarana promoted a more robust effect than caffeine. Our results show that guarana powder and caffeine have an anti-inflammatory as seen by the shift from a proinflammatory to an anti-inflammatory profile. The effects of guarana were more pronounced, suggesting that guarana powder may be used as a complementary therapy to improve the lipotoxicity-associated inflammation.

In vivo efficacy and evaluation of gel-cream containing dehydrated betamethasone dipropionate nanocapsules.

This study aimed to develop gel-creams from the lyophilised product of betamethasone dipropionate-loaded lipid-core nanocapsule suspensions and evaluated its efficacy in a model of contact dermatitis. The gel-creams were prepared and characterized followed by a study of in vitro drug penetration/permeation and its in vivo efficacy. The suspensions and lyophilised products showed nanometric size; the betamethasone content was 0.25 ± 0.01 mg/mL and the encapsulation efficiency was approximately 100%. The nanocapsules and redispersed powders presented control of the drug release. The gel-creams presented pH between 6.0-6.5 and exhibited non-Newtonian flow behavior, following the Herschel-Bulkley model. The skin penetration/permeation study indicated that betamethasone dipropionate can reach different skin layers. For in vivo efficacy, the contact dermatitis model was capable of causing tissue damage with changes in enzyme activities of the purinergic system in lymphocytes. The gel-creams showed the best dermatological and immunological efficacy and reduced oxidative damage in the evaluated tissues.

Pretreatment with quercetin prevents changes in lymphocytes E-NTPDase/E-ADA activities and cytokines secretion in hyperlipidemic rats.

Hyperlipidemia (HL) is a condition associated with endothelial dysfunction and inflammatory disorders. Purinergic system ectoenzymes play an important role in modulating the inflammatory and immune response. This study investigated whether the preventive treatment with quercetin is able to prevent changes caused by hyperlipidemia in the purinergic system, through the activities of E-NTPDase and E-ADA in lymphocytes, and quantify the nucleotides and nucleoside, and the secretion of anti- and proinflammatory cytokines. Animals were divided into saline/control, saline/quercetin 5 mg/kg, saline/quercetin 25 mg/kg, saline/quercetin 50 mg/kg, saline/simvastatin (0.04 mg/kg), hyperlipidemia, hyperlipidemia/quercetin 5 mg/kg, hyperlipidemia/quercetin 25 mg/kg, hyperlipidemia/quercetin 50 mg/kg, and hyperlipidemia/simvastatin. Animals were pretreated with quercetin for 30 days and hyperlipidemia was subsequently induced by intraperitoneal administration of 500 mg/kg of poloxamer-407. Simvastatin was administered after the induction of hyperlipidemia. Lymphocytes were isolated and E-NTPDase and E-ADA activities were determined. Serum was separated for the cytokines and nucleotide/nucleoside quantification. E-NTPDase and E-ADA activities were increased in lymphocytes from hyperlipidemic rats and pretreatment with quercetin was able to prevent the increase in the activities of these enzymes caused by hyperlipidemia. Hyperlipidemic rats when receiving pretreatment with quercetin and treatment with simvastatin showed decreased levels of ATP and ADP when compared to the untreated hyperlipidemic group. The IFN-γ and IL-4 cytokines were increased in the hyperlipidemic group when compared with control group, and decreased when hyperlipidemic rats received the pretreatment with quercetin. However, pretreatment with quercetin was able to prevent the alterations caused by hyperlipidemia probably by regulating the inflammatory process. We can suggest that the quercetin is a promising compound to be used as an adjuvant in the treatment of hyperlipidemia.

Neuroprotective effects of pretreatment with quercetin as assessed by acetylcholinesterase assay and behavioral testing in poloxamer-407 induced hyperlipidemic rats.

Hyperlipidemia is a group of disorders characterized by excessive lipids in the bloodstream. It is associated with the incidence of cardiovascular diseases and recognized as the most important factor underlying the occurrence of atherosclerosis. This study was conducted to investigate whether pretreatment with quercetin can protect against possible memory impairment and deterioration of the cholinergic system in hyperlipidemic rats. Animals were divided into ten groups (n=7): saline/control, saline/quercetin 5mg/kg, saline/quercetin 25mg/kg, saline/quercetin 50mg/kg, saline/simvastatin (0.04mg/kg), hyperlipidemia, hyperlipidemia/quercetin 5mg/kg, hyperlipidemia/quercetin 25mg/kg, hyperlipidemia/quercetin 50mg/kg and hyperlipidemia/simvastatin. The animals were pretreated with quercetin by oral gavage for a period of 30days and hyperlipidemia was subsequently induced by intraperitoneal administration of a single dose of 500mg/kg of poloxamer-407. Simvastatin was administered after the induction of hyperlipidemia. The results demonstrated that hyperlipidemic rats had memory impairment compared with the saline control group (P<0.001). However, pretreatment with quercetin and simvastatin treatment attenuated the damage caused by hyperlipidemia compared with the hyperlipidemic group (P<0.05). Acetylcholinesterase (AChE) activity in the cerebral hippocampus was significantly (P<0.001) reduced in the hyperlipidemic group compared with the control saline group. Pretreatment with quercetin and simvastatin treatment in the hyperlipidemic groups significantly (P<0.05) increased AChE activity compared with the hyperlipidemic group. Our results thus suggest that quercetin may prevent memory impairment, alter lipid metabolism, and modulate AChE activity in an experimental model of hyperlipidemia.

Guarana (Paullinia cupana) ameliorates memory impairment and modulates acetylcholinesterase activity in Poloxamer-407-induced hyperlipidemia in rat brain.

Hyperlipidemia is a risk factor for the development of cognitive dysfunction and atherosclerosis. Natural compounds have recently received special attention in relation to the treatment of disease due to their low cost and wide margin of safety. Thus, the aim of this study was to determine the possible preventive effect of guarana powder (Paullinia cupana) on memory impairment and acetylcholinesterase (AChE) activity in the brain structures of rats with Poloxamer-407-induced hyperlipidemia. Adult male Wistar rats were pretreated with guarana (12.5, 25 and 50mg/kg/day) and caffeine (0.2mg/kg/day) by gavage for a period of 30days. Simvastatin (0.04mg/kg) was administered as a comparative standard. Acute hyperlipidemia was induced with intraperitoneal injections of 500mg/kg of Poloxamer-407. Memory tests and evaluations of anxiety were performed. The cortex, cerebellum, hippocampus, hypothalamus and striatum were separated to assess acetylcholinesterase activity. Our results revealed that guarana powder was able to reduce the levels of TC and LDL-C in a manner similar to simvastatin. Guarana powder also partially reduced the liver damage caused by hyperlipidemia. Guarana was able to prevent changes in the activity of AChE and improve memory impairment due to hyperlipidemia. Guarana powder may therefore be a source of promising phytochemicals that can be used as adjuvant therapy in the management of hyperlipidemia and cognitive disorders.

Altered E-NTPDase/E-ADA activities and CD39 expression in platelets of sickle cell anemia patients.

Sickle cell anemia (SCA) is a hemoglobinopathy characterized by hemolysis and vaso-occlusions caused by rigidly distorted red blood cells. Sickle cell crisis is associated with extracellular release of nucleotides and platelets, which are critical mediators of hemostasis participating actively in purinergic thromboregulatory enzymes system.This study aimed to investigate the activities of purinergic system ecto-enzymes present on the platelet surface as well as CD39 and CD73 expressions on platelets of SCA treated patients. Fifteen SCA treated patients and 30 health subjects (control group) were selected. Ecto-nucleoside triphosphate diphosphohydrolase (E-NTPDase), ecto-5'-nucleotidase (E-5'-NT) and ecto-adenosine deaminase (E-ADA) activities were measured in platelets isolated from these individuals. Results demonstrated an increase of 41 % in the E-NTPDase for ATP hydrolysis, 52% for ADP hydrolysis and 60 % in the E-ADA activity in SCA patients (P<0.05); however, a two folds decrease in the CD39 expression in platelets was observed in the same group (P<0.01). The increased E-NTPDase activity could be a compensatory mechanism associated with the low expression of CD39 in platelets. Besides, alteration of these enzymes activities suggests that the purinergic system could be involved in the thromboregulatory process in SCA patients.

Effect of antiretroviral therapy in thromboregulation through the hydrolysis of adenine nucleotides in platelets of HIV patients.

The human immunodeficiency virus (HIV) infection results in biochemical and vascular dysfunctions. The highly active antiretroviral therapy (HAART) markedly reduces mortality and opportunistic diseases associated with acquired immunodeficiency syndrome (AIDS). This increased survival time predisposes the development of cardiovascular diseases. Platelets present purinergic system ectoenzymes such as E-NTPDase, E-5'-nucleotidase and E-ADA on its surface. In view of this, the aim of this study was to evaluate the activity of these ectoenzymes in platelets as well as the platelet aggregation and lipid profile of patients with HIV infection and also patients receiving HAART. The results showed an increase in the E-NTPDase activity for ATP hydrolysis in the HIV group compared with the control group and the HIV/HAART group. When assessing the activity E-NTPDase hydrolysis to ADP, the results revealed an increase in activity in the HIV group when compared to the control group, and a decrease in activity when in the HIV/HAART group when compared to the control and HIV groups. The activity of E-5'-nucleotidase revealed an increase in AMP hydrolysis in the HIV group, as the results from control and HIV/HAART groups showed no statistical difference. Regarding the E-ADA activity, the HIV and HIV/HAART groups revealed a decreased deamination of adenosine when compared with the control group. Furthermore, we observed an increased platelet aggregation of HIV/HAART group compared with the control group. Thus, our results suggest that antiretroviral treatment against HIV has a significant effect on the activity of purinergic system ectoenzymes demonstrating that thromboregulation is involved in the process.

Effect of Uncaria tomentosa extract on purinergic enzyme activities in lymphocytes of rats submitted to experimental adjuvant arthritis model.

BACKGROUND: Considering that adjuvant arthritis is an experimental model of arthritis widely used for preclinical testing of numerous anti-arthritic agents, which were taken by a large number of patients worldwide, it is of great interest to investigate the therapeutic action of compounds with anti-inflammatory properties, such as Uncaria tomentosa extract. Moreover, there are no studies demonstrating the effect of U. tomentosa on the metabolism of adenine nucleotides published so far. Thus, the purpose of the present study is to investigate the effects of U. tomentosa extract on E-NTPDase and E-ADA activities in lymphocytes of Complete Freund's Adjuvant (CFA) arthritis induced rats. METHODS: To evaluate the effect of U. tomentosa extract on the activity of E-NTPDase and ADA in lymphocytes, the rats were submitted to an experimental adjuvant arthritis model. Peripheral lymphocytes were isolated and E-NTPDase and E-ADA activities were determined. Data were analyzed by a one- or two-way ANOVA. Post hoc analyses were carried out by the Student-Newman-Keuls (SNK) Multiple Comparison Test. RESULTS: E-NTPDase activity was increased in arthritic untreated. Arthritic rats which received U. tomentosa extract, presented similar results to the control group. However, results obtained for adenosine hydrolysis by E-ADA were not altered in arthritic rats. U. tomentosa extract did not alter E-NTPDase and E-ADA activity in healthy animals. CONCLUSIONS: The present investigation supports the hypothesis that the increased E-NTPDase activity verified in arthritic rats might be an attempt to maintain basal levels of ATP and ADP in the extracellular medium, since the arthritis induction causes tissue damage and, consequently, large amounts of ATP are released into this milieu. Also, it highlights the possibility to use U. tomentosa extract as an adjuvant to treat arthritis.

E-NTPDase and E-ADA activities in rats experimental infected by Cryptococcus neoformans.

Cryptococcus neoformans, the etiological agent of cryptococcosis, is an opportunistic fungal pathogen of immunocompromised individuals. The aim of this study was to evaluate the activities of E-NTPDase and E-ADA in rats experimentally infected by C. neoformans var. grubii. Adult rats (35) were divided in two groups: 18 for the control group (uninfected) (A), and 17 for the infected group (B). Each group was separated into three sub-groups (A1, A2, A3-B1, B2, B3), and samples were collected on 10, 20, and 30 days post-infection (PI). Leukocyte counts, IFN-γ, TNF-α, IgM, IgG levels, and E-NTPDase and E-ADA activities were analyzed. It was possible to observe that IgG and IgM seric levels of infected rats were significantly elevated (P<0.01) on days 10, 20 and 30 PI, as well as the levels of TNF-α and INF-γ when compared to uninfected rodents. Regarding E-NTPDase activity in lymphocytes, it was possible to observe that the ATP hydrolysis was significantly decreased on days 20 (P<0.01) and 30 PI (P<0.05), while ADP hydrolysis was significantly reduced only on day 20 PI (P<0.01) when compared with uninfected group. Seric E-ADA activity had a significant reduction (P<0.01) during all three evaluated periods when compared to the control group, while E-ADA activity in lymphocytes increased significantly (P<0.01) when compared to the group A on day 10 PI; however on days 20 and 30 PI, its activity was considerable reduced in lymphocytes of infected animals (P<0.01). Therefore, it is possible to conclude that the infection caused by C. neoformans in immunocompetent rats leads to changes in the purinergic signaling (NTPDase and E-ADA), concomitantly with an inflammatory response (increased levels of cytokines and immunoglobulins) associated with inflammatory infiltrates and histological lesions in the lung.

Influence of treatment with 3'-deoxyadenosine associated deoxycoformycin on hematological parameters and activity of adenosine deaminase in infected mice with Trypanosoma evansi.

This study aimed to verify the effect of 3'-deoxyadenosine and deoxycoformycin on hematologic parameters and adenosine deaminase (ADA) activity in plasma and brain of mice infected with Trypanosoma evansi. Seventy animals were divided into seven groups, which were divided into two subgroups each for sampling on days 4 and 8 post-infection (PI). The groups were composed of three uninfected groups (A-C), namely, not-treated (A), treated with 3'-deoxyadenosine (B), and treated with deoxycoformycin (C) and four infected groups, mice with T. evansi (D-G), namely, not-treated (D), treated with 3'-deoxyadenosine (E), treated with deoxycoformycin (F), and treated with a combination 3'-deoxyadenosine and deoxycoformycin (G). Hematological parameters and ADA activity were evaluated in plasma and brain. Animals in groups B and C exhibited a reduction in the levels of plasma total protein compared group A. Animals in groups D and F showed changes in the hematological parameters. The ADA activity significantly reduced in the animals of groups C, D, F and G. Mice in the group E presented increased ADA activity in plasma. Therefore, we conclude that the treatment interferes significantly in the hematologic parameters in mice infected with T. evansi. On the other hand, when the ADA inhibitor was used we observed a significant decrease in the values of hematocrit, total erythrocytes, and hemoglobin concentration. The deoxycoformycin was able to inhibit the ADA activity of parasite thus it may be one of the mechanisms of efficacy of this treatment.

E-NTPDase and E-ADA activities in lymphocytes associated with the immune response of rats experimentally infected with Toxoplasma gondii.

An investigation of E-NTPDase and E-ADA activities in lymphocytes from rats experimentally infected with Toxoplasma gondii was carried out in this study. For this purpose, twenty four adult male Wistar rats were divided in two groups/four subgroups (A1 and A2; B1 and B2-6 animal/each group), with "A" as uninfected and "B" inoculated with T. gondii (RH strain). Sampling was performed on days 5 and 10 post-infection (p.i.), with evaluation of hemogram, immunoglobulins (IgM and IgG) and activity of E-NTPDase and E-ADA in lymphocytes. Enzymes essays showed ATP hydrolysis increased on days 5 (P<0.05) and 10 (P<0.01) p.i., as well as an increase of ADP hydrolysis on day 10 (P<0.01) p.i. E-ADA activity on lymphocytes was also increased in both evaluated periods (P<0.01). Based on E-NTPDase and E-ADA increased activities observed on lymphocytes, it is possible to suggest their involvement in an anti-inflammatory response, consisting of a modulatory response, preventing excessive tissue damage caused by the infection with Toxoplasma gondii.