Extraction of Phenolic Compounds from Tabernaemontana catharinensis Leaves and Their Effect on Oxidative Stress Markers in Diabetic Rats.

The aim of this study was to evaluate the most effective extraction condition (temperature, solvent type and time) for recovery of high-value phytochemicals present in the Tabernaemontana catharinensis leaves (TC) and to assess their effect on biochemical parameters in streptozotocin-induced diabetic rats. The extraction of phenolic compounds from TC using a factorial design (FD) 2³, high performance liquid chromatography (HPLC), response surface methodology (RSM) and principal component analysis (PCA) were studied. It was found that the optimal conditions for extraction of phenolics were higher temperature (65 °C) and time (60 min) using ethanol as extractor solvent. In this condition of extraction (A8), total phenolic compounds (TPC) and antioxidant activity (AA) were determined. Additionally, this extract was used to evaluate their effect on antioxidant enzyme activities (superoxide dismutase (SOD) and catalase (CAT)) as well as lipid peroxidation (LP) and protein thiols level (PSH) in the liver and kidneys of normal and diabetic rats. As result, T. catharinensis extract presented TPC content of 23.34 mg EAG/g (equivalent gallic acid) and AA of 34.26 µmol Trolox/g. Phenolic acids (ferulic acid and coumaric acid) and flavonoids (quercetin, rutin and pinocembrin) could be recovered and identified by HPLC. This study indicated an important role of the T. catharinensis extract on free radical inactivation and on the antioxidant defense system in diabetic rats. In fact, the use of T. catharinensis extract restored the normal activity of SOD (p < 0.05) and suppressed malondialdehyde levels in liver and kidney tissues. Thus, the T. catharinensis extract, rich in phenolic compounds, can be responsible for the recover the enzymatic changes in the liver and kidney tissues provoked by diabetes in rats. In addition, the lipid peroxidation rate decreased in the diabetic rats treated with T. catharinensis.

Effect of Ginger and Turmeric Rhizomes on Inflammatory Cytokines Levels and Enzyme Activities of Cholinergic and Purinergic Systems in Hypertensive Rats.

Inflammation exerts a crucial pathogenic role in the development of hypertension. Hence, the aim of the present study was to investigate the effects of ginger (Zingiber officinale) and turmeric (Curcuma longa) on enzyme activities of purinergic and cholinergic systems as well as inflammatory cytokine levels in Nω-nitro-L-arginine methyl ester hydrochloride-induced hypertensive rats. The rats were divided into seven groups (n = 10); groups 1-3 included normotensive control rats, hypertensive (Nω-nitro-L-arginine methyl ester hydrochloride) rats, and hypertensive control rats treated with atenolol (an antihypertensive drug), while groups 4 and 5 included normotensive and hypertensive (Nω-nitro-L-arginine methyl ester hydrochloride) rats treated with 4 % supplementation of turmeric, respectively, and groups 6 and 7 included normotensive and hypertensive rats treated with 4 % supplementation of ginger, respectively. The animals were induced with hypertension by oral administration of Nω-nitro-L-arginine methyl ester hydrochloride, 40 mg/kg body weight. The results revealed a significant increase in ATP and ADP hydrolysis, adenosine deaminase, and acetylcholinesterase activities in lymphocytes from Nω-nitro-L-arginine methyl ester hydrochloride hypertensive rats when compared with the control rats. In addition, an increase in serum butyrylcholinesterase activity and proinflammatory cytokines (interleukin-1 and - 6, interferon-γ, and tumor necrosis factor-α) with a concomitant decrease in anti-inflammatory cytokines (interleukin-10) was observed in Nω-nitro-L-arginine methyl ester hydrochloride hypertensive rats. However, dietary supplementation of both rhizomes was efficient in preventing these alterations in hypertensive rats by decreasing ATP hydrolysis, acetylcholinesterase, and butyrylcholinesterase activities and proinflammatory cytokines in hypertensive rats. Thus, these activities could suggest a possible insight about the protective mechanisms of the rhizomes against hypertension-related inflammation.

Dietary Supplementation of Ginger and Turmeric Rhizomes Modulates Platelets Ectonucleotidase and Adenosine Deaminase Activities in Normotensive and Hypertensive Rats.

Hypertension is associated with platelet alterations that could contribute to the development of cardiovascular complications. Several studies have reported antiplatelet aggregation properties of ginger (Zingiber officinale) and turmeric (Curcuma longa) with limited scientific basis. Hence, this study assessed the effect of dietary supplementation of these rhizomes on platelet ectonucleotidase and adenosine deaminase (ADA) activities in Nω-nitro-l-arginine methyl ester hydrochloride (l-NAME) induced hypertensive rats. Animals were divided into seven groups (n = 10): normotensive control rats; induced (l-NAME hypertensive) rats; hypertensive rats treated with atenolol (10 mg/kg/day); normotensive and hypertensive rats treated with 4% supplementation of turmeric or ginger, respectively. After 14 days of pre-treatment, the animals were induced with hypertension by oral administration of l-NAME (40 mg/kg/day). The results revealed a significant (p < 0.05) increase in platelet ADA activity and ATP hydrolysis with a concomitant decrease in ADP and AMP hydrolysis of l-NAME hypertensive rats when compared with the control. However, dietary supplementation with turmeric or ginger efficiently prevented these alterations by modulating the hydrolysis of ATP, ADP and AMP with a concomitant decrease in ADA activity. Thus, these activities could suggest some possible mechanism of the rhizomes against hypertension-derived complications associated to platelet hyperactivity. Copyright © 2016 John Wiley & Sons, Ltd.

Extracellular Hydrolysis of Adenine Nucleotides and Nucleoside Adenosine is Higher in Patients with ST Elevation than Non-ST Elevation in Acute Myocardial Infarction.

BACKGROUND: The hydrolysis of adenine nucleotide linked to the membrane of the platelets is changed in acute myocardial infarction (AMI) probably due to a greater arterial blockage and cell damage in patients with ST elevation (STEMI) than in those without ST segment elevation (NSTEM). METHODS: This study aimed to compare the extracellular hydrolysis of adenine nucleotides on the platelet surface of STEMI and NSTEMI patients. This study was carried out with 50 patients with AMI (STEMI and NSTEMI). The extracellular hydrolysis of adenine nucleotides and nucleoside adenosine as well as the expression of NTPDase were verified in platelets. RESULTS: The results demonstrated that STEMI patients had significantly higher extracellular hydrolysis of adenine nucleotides (p < 0.001), ADA (adenosine deaminase) activity (p < 0.05), as well as troponin levels (p < 0.0001) when compared to NSTEMI patients. CONCLUSIONS: Findings suggest that the extracellular hydrolysis of adenine nucleotides and increase in the ADA activity are higher in patients with STEMI than in those with NSTEMI probably because there was a blockage in this major arterial with a large area of damaged tissue.

Effect of vitamin D3 on behavioural and biochemical parameters in diabetes type 1-induced rats.

Diabetes is associated with long-term complications in the brain and reduced cognitive ability. Vitamin D3 (VD3 ) appears to be involved in the amelioration of hyperglycaemia in streptozotocin (STZ)-induced diabetic rats. Our aim was to analyse the potential of VD3 in avoiding brain damage through evaluation of acetylcholinesterase (AChE), Na(+) K(+) -adenosine triphosphatase (ATPase) and delta aminolevulinate dehydratase (δ-ALA-D) activities and thiobarbituric acid reactive substance (TBARS) levels from cerebral cortex, as well as memory in STZ-induced diabetic rats. Animals were divided into eight groups (n = 5): control/saline, control/metformin (Metf), control/VD3 , control/Metf + VD3 , diabetic/saline, diabetic/Metf, diabetic/VD3 and diabetic/Metf + VD3 . Thirty days after treatment, animals were submitted to contextual fear-conditioning and open-field behavioural tests, after which they were sacrificed and the cerebral cortex was dissected. Our results demonstrate a significant memory deficit, an increase in AChE activity and TBARS levels and a decrease in δ-ALA-D and Na(+) K(+) -ATPase activities in diabetic rats when compared with the controls. Treatment of diabetic rats with Metf and VD3 prevented the increase in AChE activity when compared with the diabetic/saline group. In treated diabetic rats, the decrease in Na(+) K(+) -ATPase was reverted when compared with non-treated rats, but the increase in δ-ALA-D activity was not. VD3 prevented diabetes-induced TBARS level and improved memory. Our results show that VD3 can avoid cognitive deficit through prevention of changes in important enzymes such as Na(+) K(+) -ATPase and AChE in cerebral cortex in type 1 diabetic rats.

Vitamin E decreased the activity of acetylcholinesterase and level of lipid peroxidation in brain of rats exposed to aged and diluted sidestream smoke.

INTRODUCTION: The biological systems of both smoker and passive smoking suffer changes caused by toxic compounds from cigarette smoke such as inflammation, lipid peroxidation, and deficiency of vitamin E. The aim of the present study was to evaluate the effect of vitamin E on acetylcholinesterase (AChE) activity and the lipid peroxidation level in the brain of rats in the model of exposure to aged and diluted sidestream smoke (ADSS). METHODS: Adult male Wistar rats (200-300 g) were exposed to ADSS for 4 weeks and treated with vitamin E (50 mg/kg/day) loaded by gavage. In the first, second, third, and fourth weeks, animals were concomitantly exposed to the smoke of 1, 2, 3, and 4 cigarettes/day, respectively. The duration of each exposure was 15 min, daily. RESULTS: For rats exposed to ADSS, the AChE activity and lipid peroxidation level increased in the striatum, cerebral cortex, and cerebellum. In contrast, the activity of AChE and the level of lipid peroxidation decreased in the smoke group treated with vitamin E. CONCLUSIONS: The results suggest that the rats exposed to ADSS and treated with vitamin E significantly reduced the raised activity of AChE and level lipid peroxidation from the brain structures studied. The study, therefore, concludes that vitamin E could be considered as a therapeutic agent in this type of exposure.

The effect of curcumin in the ectonucleotidases and acetylcholinesterase activities in synaptosomes from the cerebral cortex of cigarette smoke-exposed rats.

With the evidence that curcumin may be a potent neuroprotective agent and that cigarette smoke is associated with a decline in the cognitive performance as our bases, we investigated the activities of Ecto-Nucleoside Triphosphate Diphosphohydrolase (NTPDase), 5'-nucleotidase and acetylcholinesterase (AChE) in cerebral cortex synaptosomes from cigarette smoke-exposed rats treated with curcumin (Cur). The experimental procedures entailed two sets of experiments. In the first set, the groups were vehicle, Cur 12·5, 25 and 50 mg·kg(-1) ; those in the second set were vehicle, smoke, smoke and Cur 12·5, 25 and 50 mg·kg(-1) . Curcumin prevented the increased NTPDase, 5'-nucleotidase and AChE activities caused by smoke exposure. We suggest that treatment with Cur was protective because the decrease of ATP and acetylcholine (ACh) concentrations is responsible for cognitive impairment, and both ATP and ACh have key roles in neurotransmission.

Selenothymidine protects against biochemical and behavioral alterations induced by ICV-STZ model of dementia in mice.

The present study evaluated the neuroprotective effects of one selenium-containing AZT derivative compound (S1073) in memory and learning impairment caused by Intracerebroventricular-streptozotocin (ICV-STZ). ICV-STZ in mice causes impairment of energy metabolism with oxidative damage and cholinergic dysfunction, and provides a relevant model for sporadic dementia of Alzheimer's type (AD). Acetylcolinesterase (AChE), Catalase (CAT), dichlorofluorescein oxidation (DCFH), TBARS and thiol content were measured. Swiss adult mice were pre-treated with S1073 [1 mmol/kg] (i.p.) and after 30 min of the injection received a bilateral dose of STZ [11.3 µmol/l]. After 8 days' STZ injection, we performed the behavioral experiments (Beaker test, Open field and Morris water maze task). ICV-STZ caused significant learning and memory impairments, which were significantly improved by S1073 pre-treatment. A significant increase in cerebral DFCH, TBARS levels and AChE activity and a disturbance in the memory and learning were observed in ICV-STZ injected animals. S1073 significantly ameliorated all alterations induced by ICV-STZ in mice. All these findings support the neuroprotective role of S1073 in mice model of Alzheimer's dementia-type induced by ICV-STZ, which may be associated with its antioxidant activity and/or with its inhibitory effect in brain AChE. In fact, in silico analysis indicated that S1073 may be an inhibitor of AChE.

Effects of gallic acid on delta - aminolevulinic dehydratase activity and in the biochemical, histological and oxidative stress parameters in the liver and kidney of diabetic rats.

Diabetes mellitus (DM) is characterised by hyperglycaemia associated with the increase of oxidative stress. Gallic acid has potent antioxidant properties. The aim of this study was to evaluate the effect of gallic acid on the biochemical, histological and oxidative stress parameters in the liver and kidney of diabetic rats. Male rats were divided in groups: control, gallic acid, diabetic and diabetic plus gallic acid. DM was induced in the animals by intraperitoneal injection of streptozotocin (65mg/kg). Gallic acid (30mg/kg) was administered orally for 21days. Our results showed an increase in reactive species levels and lipid peroxidation, and a decrease in activity of the enzymes superoxide dismutase and delta-aminolevulinic acid dehydratase in the liver and kidney of the diabetic animals (P<0.05). Gallic acid treatment showed protective effects in these parameters evaluated, and also prevented a decrease in the activity of catalase and glutathione S-transferase, and vitamin C levels in the liver of diabetic rats. In addition, gallic acid reduced the number of nuclei and increased the area of the core in hepatic tissue, and increased the glomerular area in renal tissue. These results indicate that gallic acid can protect against oxidative stress-induced damage in the diabetic state.

Dietary supplementation of ginger and turmeric improves reproductive function in hypertensive male rats.

Ginger [Zingiber officinale Roscoe (Zingiberaceae)] and turmeric [Curcuma longa Linn (Zingiberaceae)] rhizomes have been reportedly used in folk medicine for the treatment of hypertension. However, the prevention of its complication such as male infertility remains unexplored. Hence, the aim of the present study was to investigate the preventive effects of ginger and turmeric rhizomes on some biomarkers of male reproductive function in L-NAME-induced hypertensive rats. Male Wistar rats were divided into seven groups (n = 10): normotensive control rats; induced (L-NAME hypertensive) rats; hypertensive rats treated with atenolol (10 mg/kg/day); normotensive and hypertensive rats treated with 4% supplementation of turmeric or ginger, respectively. After 14 days of pre-treatment, the animals were induced with hypertension by oral administration of L-NAME (40 mg/kg/day). The results revealed significant decrease in serum total testosterone and epididymal sperm progressive motility without affecting sperm viability in hypertensive rats. Moreover, increased oxidative stress in the testes and epididymides of hypertensive rats was evidenced by significant decrease in total and non-protein thiol levels, glutathione S-transferase (GST) activity with concomitant increase in 2',7'-dichlorofluorescein (DFCH) oxidation and thiobarbituric acid reactive substances (TBARS) production. Similarly, decreased testicular and epididymal NO level with concomitant elevation in arginase activity was observed in hypertensive rats. However, dietary supplementation with turmeric or ginger efficiently prevented these alterations in biomarkers of reproductive function in hypertensive rats. The inhibition of arginase activity and increase in NO and testosterone levels by both rhizomes could suggest possible mechanism of action for the prevention of male infertility in hypertension. Therefore, both rhizomes could be harnessed as functional foods to prevent hypertension-mediated male reproductive dysfunction.

Diphenyl ditelluride intoxication triggers histological changes in liver, kidney, and lung of mice.

Tellurium compounds may be cytotoxic to different cells types. Thus, this work evaluated the effect of diphenyl ditelluride ((PhTe)2), an organotellurium commonly used in organic synthesis, on the morphology of liver, kidney, and lung. Adult mice were acutely (a subcutaneous single dose: 250 µmol/kg) or subchronically (one daily subcutaneous dose: 10 or 50 µmol/kg for 7 and 14 days) exposed to (PhTe)2. Afterwards, the histological analyses of liver, kidney, and lungs were performed. Liver histology revealed that the hepatocytes of mice subchronically exposed to (PhTe)2 presented cytoplasmic vacuolization, hydropic degeneration, and hyperchromatic nuclei. Subchronic exposure to 50 µmol/kg (PhTe)2 also caused hepatic necrosis. Microvesicular and macrovesicular steatosis were identified in liver of mice acutely exposed to (PhTe)2. Acute and subchronic intoxication with (PhTe)2 induced changes on epithelial cells of renal tubules, namely, loss of brush border and cytoplasmatic vacuolization. Atrophy and hypertrophy, cast proteinaceous formation, and acute tubular necrosis were also identified in renal tissue. Mice subchronically exposed to 50 µmol/kg (PhTe)2 developed intra-alveolar edema and alveolar wall congestion in some areas of lungs. Acute exposure to (PhTe)2 did not cause histological changes in lungs. Our data show that (PhTe)2 may be considered a histotoxic agent for liver, kidney, and lung.

Lung cancer alters the hydrolysis of nucleotides and nucleosides in platelets.

BACKGROUND: The nucleotides and nucleosides of adenine are signaling molecules related to thromboregulation and modulation of immune responses in patients with malignancies. Thus, this study aims to determine NTPDase, 5'-nucleotidase, ectonucleotide pyrophosphatase/phosphodiesterase (E-NPP) and adenosine deaminase (ADA) activities in the platelets of patients with lung cancer. METHODS: We collected blood samples from patients (n=33) previously treated for lung cancer with chemotherapy. Patients were classified as stage IIIb and IV according to the Union for International Cancer Control (UICC). RESULTS: Patients showed a significant decrease in the hydrolysis of adenosine diphosphate (ADP) and adenosine, whereas the adenosine monophosphate (AMP) hydrolysis and platelet aggregation were significantly increased in this group. Adenosine triphosphate (ATP) hydrolysis did not show significant results between the group of patients and the control group. CONCLUSIONS: We may suggest that ectonucleotidases as well as ADA are enzymes involved in thromboembolic events but especially here we may see that they are also directly involved in the generation of adenosine formation in the cancer patient circulation.

Nicotine alters the ectonucleotidases activities in lymphocytes: In vitro and in vivo studies.

The aim of the present study was to investigate the effects in vivo and in vitro of nicotine, an important immunosuppressive agent, on NTPDase and ADA activities in lymphocytes of adult rats. The following nicotine doses in vivo study were evaluated: 0.0, 0.25 and 1.0mg/kg/day injected subcutaneously in rats for 10days. The activity of the enzymes were significantly decreased with nicotine 0.25 and 1mg/kg which inhibited ATP (22%, 54%), ADP (44%, 30%) hydrolysis and adenosine (43%, 34%) deamination, respectively. The expression of the protein NTPDase in rat lymphocytes was decreased to nicotine 1mg/kg and the lymphocytes count was decreased in both nicotine doses studied. The purine levels measured in serum of the rats treated with nicotine 0.25mg/kg significantly increased to ATP (39%), ADP (39%) and adenosine (303%). The nicotine exposure marker was determinate by level of cotinine level which significantly increased in rats treated with nicotine 0.25 (39%) and 1mg/kg (131%) when compared to rats that received only saline. The second set of study was in vitro assay which the ATP-ADP-adenosine hydrolysis were decreased by nicotine concentrations 1mM (0% - 0% - 16%, respectively), 5mM (42% - 32% - 74%, respectively), 10mM (80% - 27% - 80%, respectively) and 50mM (96% - 49% - 98%, respectively) when compared with the control group. We suggest that alterations in the activities of these enzymes may contribute to the understanding of the mechanisms involved in the suppression of immune response caused by nicotine.