Systemic and local effects of doxycycline and low-intensity laser treatment on periodontitis in rats.

PURPOSE: This study evaluated the systemic and local effects of doxycycline (DOX) and low-intensity laser (LIL) treatment as adjuvants to scaling and root planing (SRP) in the treatment of experimental periodontitis in rats. METHODS: The sample consisted of 180 male rats (Rattus norvegicus albinus, Wistar), of which 30 did not receive induction of periodontal disease (negative control [NC] group) and 150 received induction of periodontal disease in the lower first molar. After 7 days, the ligature was removed, and the animals were divided into the following groups: NT (no treatment), SRP (SRP), DOX (SRP and DOX irrigation), LIL (SRP and laser irradiation), and DOX+LIL (SRP, DOX, and LIL). The animals were euthanized at 7, 15, and 30 days; thereafter, biochemical, radiographic, histological, and immunohistochemical analyses were performed. RESULTS: In the intragroup analysis, lower concentrations of α-1-glycoprotein acid (α-1-Ga) and complement 3 (C3) were observed in the DOX+LIL group than in all other groups at all time points, as well as lower levels of complement 4 (C4) at 15 and 30 days (P<0.001). Less bone loss was observed in the DOX, LIL, and DOX+LIL groups than in the NC and SRP groups at all time points (P<0.001). There was a smaller number of tartrate-resistant acid phosphatase (TRAP)-positive cells in the DOX+LIL group than in the other groups at all time points (P<0.001). Positive correlations were observed between the systemic levels of α-1-Ga, C3, and C4 and the number of TRAP-positive cells. CONCLUSIONS: The combination of DOX with LIL as SRP adjuvants was effective both systemically and locally for the treatment of experimental periodontitis in rats.

Photobiomodulation enhances the Th1 immune response of human monocytes.

This study aims to evaluate the effects of photobiomodulation (PBM) on human monocytes, assessing the oxidative burst and ultimate fungicidal potential of these cells, as well as the gene expression at the mRNA level of CD68, CD80, CD163, CD204, IL-6, TNF-α and IL-10 in derived macrophages. Primary cultures of human monocytes were irradiated with an InGaAlP (660 nm)/GaAlAs (780 nm) diode laser (parameters: 40 mW, 0.04 cm2, 1 W/cm2; doses: 200, 400 and 600 J/cm2). Cells were submitted to the chemiluminescence assay, and a microbicidal activity assay against Candida albicans was performed. Reactive oxygen species (ROS) and nitric oxide (NO) production were measured, and cell viability was assessed by the exclusion method using 0.2% Trypan blue reagent. Irradiated monocytes were cultured for 72 h towards differentiation into macrophages. Total RNA was extracted, submitted to reverse transcription and real-time PCR. The results were analysed by ANOVA and the Tukey test (α = 0.05). Irradiated monocytes revealed a significant increase in their intracellular and extracellular ROS (P < 0.001). The 660 nm wavelength and 400 J/cm2 dose were the most relevant parameters (P < 0.001). The fungicidal capacity of the monocytes was shown to be greatly increased after PBM (P < 0.001). PBM increased the expression of TNF-α (P = 0.0302) and the production of NO (P < 0.05) and did not impair monocyte viability. PBM induces a pro-inflammatory Th1-driven response in monocytes and macrophages.

Influence of Doxycycline and InGaAlP Diode Laser at 660 nm Wavelength in the Treatment of Periodontitis Induced in Rats: In Vivo Study.

This study evaluated the influence of Doxycycline (DOX) and Low-Intensity Laser (LIL) (InGaAlP diode laser) as scaling and root planing (SRP) adjuvants in the treatment of periodontitis induced in rats. The rats received periodontal disease induction, and after 7 days, the ligature was removed, and the animals were divided into groups/treatments: NT-receive no treatment; SRP-submitted only to SRP; DOX-submitted to SRP and DOX irrigation; LIL-submitted to SRP and LIL irradiation; and DOX + LIL-submitted to SRP treatments, DOX irrigation and LIL irradiation. The animals were sacrificed at 7, 15 and 30 days, and then, the analyses were performed. A lower concentration of Alpha-glycoprotein acid and Complement 3 was observed in the DOX + LIL group compared to all the other groups in all the periods, and for Complement 4 at 15 and 30 days (P < 0.01). A lower bone loss (BL) was observed in the DOX + LIL group compared to all the other groups in all the periods (P < 0.01). It can be concluded that LIL was effective in the reduction of proteins, and its association with DOX was effective in the reduction of proteins and BL, in the treatment of periodontal induction in rats.

Tempol modulates the leukocyte response to inflammatory stimuli and attenuates endotoxin-induced sickness behaviour in mice.

Background and aims: Lipopolysaccharide (LPS), an endotoxin, is a component of the outer membrane of Gram-negative bacteria that is able to activate the peripheral immune system, leading to changes in signalling pathways that act locally and systemically to achieve adaptive responses. Sickness behaviour is a motivational state in response to endotoxin exposure and includes depressed activity and a reduction of exploratory behaviour, potentially reorganising organism priorities to cope with infectious diseases. We hypothesised that 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl (Tempol) modulates the leukocyte response to endotoxins and decreases LPS-induced sickness behaviour in mice.Methods: The effects of Tempol on LPS-induced peritonitis and the respiratory burst of neutrophils primed with LPS and triggered by phorbol 12-myristate-13-acetate (PMA) were evaluated. To evaluate the effects of Tempol on sickness behaviour, the mice were submitted to an open field and forced swim tests.Results: Tempol (50-100 µM/106 cells) decreased the respiratory burst of LPS-primed and PMA-stimulated neutrophils in vitro. In vivo, this nitroxide (30 and 100 mg/kg body weight) inhibited leukocyte migration to the peritoneal cavity after LPS administration in mice. Moreover, Tempol pretreatment (30 and 100 mg/kg body weight) before LPS administration also attenuated sickness behavioural changes.Conclusions: Together, these findings shed light on the mechanisms underlying the anti-inflammatory potential and confirm the therapeutic potential of nitroxides.

Passiflora edulis Leaf Extract: Evidence of Antidiabetic and Antiplatelet Effects in Rats.

Different Passiflora species have been appointed as a promising herbal medicine due to antioxidant properties; however, their effect on oxidative process induced by diabetes is still controversial. We aimed to evaluate effects of hydroethanolic extract 70% from P. edulis leaf on biochemical blood markers, collagen glycation, production of oxidant species and platelet aggregation in diabetic rats. The phytochemical analysis of the extract was performed by dereplication using LC coupled to the Photodiode Array Detector and Mass Spectrometer detector. Male Wistar rats were assigned to the control group and groups treated with alloxan (150 mg/kg) intraperitoneally, extract (200 mg/kg/d, for 90 d) and combination of alloxan and extract. The phytochemical analysis suggested the presence of flavonoids C-glycosides in the extract. The diabetic animals treated with the extract presented improvement in glycaemic control, reduced glycation collagen, levels of non-high density lipoprotein (non-HDL) cholesterol, total cholesterol and creatinine, production of oxidant species and aggregation in platelet in relation to diabetic animals non-treated. Our results showed that P. edulis leaf extract presents a health benefit to the diabetic state, preventing the appearance of its complications. Its effect can be associated with flavonoids, among which is the flavonoid C-glycoside isoorientin.

Photodynamic therapy for Schistosoma mansoni: Promising outcomes.

The purpose of this study was to assess, for the very first time, the effects of photodynamic therapy (PDT) on Schistosoma mansoni in vitro by measuring reactive oxygen species (ROS) generation throughout the treatment, as well as the behavior of the parasites (mating, motility and contraction/shortening), and damage to their tegument and excretory systems. The parasites were divided into 4 groups: control, photosensitizer, laser and PDT. Light irradiation was delivered with an InGaAlP low-level laser device operating at 660nm, with 40mW and 100J/cm2. For PDT, different toluidine blue dye (TBO) concentrations and times of exposure were utilized. Interestingly, TBO-mediated PDT was able to kill S. mansoni (P<0.001) due to the significant amount of ROS released that inflicted damages in the tegument and excretory system, as well as contraction and cessation of motility. In addition, males of S. mansoni were shown to be more sensitive to PDT if compared to their corresponding females when the optimal TBO concentration of 31.2µL was considered (P=0.0126). PDT presents two major advantages: not inducing microbial resistance and also lacking adverse effects. Therefore, PDT may become a promising therapeutic alternative for schistosomiasis in the near future, especially for cases of allergy and resistance to praziquantel.

Treatment of experimental periodontal disease by laser therapy in simvastatin-modified rats.

OBJECTIVE: The aim of this study was to evaluate low-level laser therapy (LLLT) as an adjuvant treatment for scaling and root planing (SRP) for the treatment of induced periodontitis in simvastatin-modified rats. MATERIAL AND METHODS: A total of 180 rats were evenly divided into two groups: Veh - receiving oral administration of polyethylene glycol (vehicle); S - receiving oral administration of Simvastatin. Periodontal disease was induced in both groups at the first mandibular molar. After seven days, the ligature was removed and the animals were divided into subgroups according to the following local treatments: NT - no treatment; SRP - scaling and root planing and irrigation with saline solution; and LLLT ¬- SRP and laser irradiation (660 nm; 0.03 W; 4 J). Ten animals in each subgroup/local treatment were euthanized at 7, 15 and 30 days. Samples of gingival tissue were processed to analyze the tissue oxidative damage and radiographic analysis. Levels of oxidative stress were analyzed by the expressions of Tripeptideglutathione (TG), Malondialdehyde (MDA) and Carbonylated Proteins (CP). RESULTS: The animals in S group had higher levels of TG and lower levels of MDA and CP compared with Veh group (p<0.05). Radiographically, in the intragroup analysis Veh and S, LLLT showed lower bone loss (BL) compared with NT and SRP, in all experimental periods (p<0.01). In addition, a lower BL was observed for the animals of Veh group treated with LLLT compared with treatment SRP in the S group, in all experimental periods. CONCLUSION: Within the limits of this study, we can conclude that LLLT was effective as adjuvant treatment for SRP protecting against the occurrence of oxidative tissue damages as well as for reducing alveolar bone loss in experimentally induced periodontitis simvastatin-modified rats.

Treatment of experimental periodontal disease by laser therapy in simvastatin-modified rats

Abstract Low intensity laser can be used as a promising alternative in the treatment of periodontal disease. Objective The aim of this study was to evaluate low-level laser therapy (LLLT) as an adjuvant treatment for scaling and root planing (SRP) for the treatment of induced periodontitis in simvastatin-modified rats. Material and Methods A total of 180 rats were evenly divided into two groups: Veh - receiving oral administration of polyethylene glycol (vehicle); S - receiving oral administration of Simvastatin. Periodontal disease was induced in both groups at the first mandibular molar. After seven days, the ligature was removed and the animals were divided into subgroups according to the following local treatments: NT - no treatment; SRP - scaling and root planing and irrigation with saline solution; and LLLT ¬- SRP and laser irradiation (660 nm; 0.03 W; 4 J). Ten animals in each subgroup/local treatment were euthanized at 7, 15 and 30 days. Samples of gingival tissue were processed to analyze the tissue oxidative damage and radiographic analysis. Levels of oxidative stress were analyzed by the expressions of Tripeptideglutathione (TG), Malondialdehyde (MDA) and Carbonylated Proteins (CP). Results The animals in S group had higher levels of TG and lower levels of MDA and CP compared with Veh group (p<0.05). Radiographically, in the intragroup analysis Veh and S, LLLT showed lower bone loss (BL) compared with NT and SRP, in all experimental periods (p<0.01). In addition, a lower BL was observed for the animals of Veh group treated with LLLT compared with treatment SRP in the S group, in all experimental periods. Conclusion Within the limits of this study, we can conclude that LLLT was effective as adjuvant treatment for SRP protecting against the occurrence of oxidative tissue damages as well as for reducing alveolar bone loss in experimentally induced periodontitis simvastatin-modified rats.

Nitroxide 4-hydroxy-2,2',6,6'-tetramethylpiperidine 1-oxyl (Tempol) inhibits the reductase activity of protein disulfide isomerase via covalent binding to the Cys400 residue on CXXC redox motif at the a'active site.

BACKGROUND AND AIM: Oxidative stress arising from inflammatory processes is a serious cause of cell and tissue damage. Tempol is an efficient antioxidant with superoxide dismutase-like activity. The purpose of this paper is to address the inhibition of protein disulfide isomerase (PDI), an essential redox chaperone whose active sites contain the Cys-Gly-His-Cys (CXXC) motif, by the nitroxide Tempol. RESULTS: In the presence of Tempol (5-120 µM), the reductase activity of PDI was reversibly affected both in vitro and in activated mice neutrophils, with an IC50 of 22.9 ± 10.8 µM. Inhibitory activity was confirmed by using both the insulin method and fluorescent formation of eosin-glutathione (E-GSH). The capacity of Tempol to bind the enzyme was determined by EPR and mass spectrometry. EPR Tempol signal decreased in the presence of PDI while remained unaffected when PDI thiols were previously blocked with NEM. When total protein was analyzed, 1 and 4 molecules of Tempol were bound to the protein. However, only one was found to be covalently bound to PDI at the a'active site. More specifically, Cys400 was modified by Tempol. CONCLUSION: We have shown that the nitroxide Tempol acts as an inhibitor of PDI through covalent binding to the Cys400 of the protein structure. Since PDI is coupled with the assembly of the NADPH oxidase complex of phagocytes, these findings reveal a novel action of Tempol that presents potential clinical applications for therapeutic intervention to target PDI knockdown in pathological processes in which this protein is engaged.

Local application of statins in the treatment of experimental periodontal disease in rats.

OBJECTIVE: The objective of this study was to evaluate the local effects of statins as adjuvants for treatment by scaling and root planing (SRP) of periodontal disease induced in rats. MATERIAL AND METHODS: Ninety rats were used in the present experiment. Periodontal disease was induced in all animals using a cotton thread placed in the left first mandibular molar. After 7 days of induction, the bandage was removed and the animals were divided into three groups: 1) NT group (n=30), no treatment; 2) SRP group (n=30): SRP and irrigation with control gel; 3) S group (n=30) - SRP and irrigation with Simvastatin. Ten animals from each group were euthanized at 7, 15 and 30 days after treatment. Gingival biopsy specimens were processed to analyze the expression of matrix metalloproteinase 8 (MMP-8). The mandibles were removed and submitted to radiographic and laboratory processing for histometric analysis. RESULTS: The S group showed a significantly lower expression of MMP-8 compared to NT and SRP groups in all experimental periods. In the radiographic and histometric analyses between the groups, S group showed a significantly lower bone loss (BL) compared to NT and SRP groups in all experimental periods. CONCLUSIONS: Within the limits of this study, it can be concluded that locally applied statin was effective as an adjuvant treatment for SRP in rats with induced periodontal disease.

Local application of statins in the treatment of experimental periodontal disease in rats

Abstract Objective The objective of this study was to evaluate the local effects of statins as adjuvants for treatment by scaling and root planing (SRP) of periodontal disease induced in rats. Material and Methods Ninety rats were used in the present experiment. Periodontal disease was induced in all animals using a cotton thread placed in the left first mandibular molar. After 7 days of induction, the bandage was removed and the animals were divided into three groups: 1) NT group (n=30), no treatment; 2) SRP group (n=30): SRP and irrigation with control gel; 3) S group (n=30) - SRP and irrigation with Simvastatin. Ten animals from each group were euthanized at 7, 15 and 30 days after treatment. Gingival biopsy specimens were processed to analyze the expression of matrix metalloproteinase 8 (MMP-8). The mandibles were removed and submitted to radiographic and laboratory processing for histometric analysis. Results The S group showed a significantly lower expression of MMP-8 compared to NT and SRP groups in all experimental periods. In the radiographic and histometric analyses between the groups, S group showed a significantly lower bone loss (BL) compared to NT and SRP groups in all experimental periods. Conclusions Within the limits of this study, it can be concluded that locally applied statin was effective as an adjuvant treatment for SRP in rats with induced periodontal disease.

Efeitos da Sinvastatina como coadjuvante no tratamento da doença periodontal induzida em ratos / Effects of Simvastatin as supporting in the treatment of periodontal disease induced in rats

O estudo avaliou a Sinvastatina no tratamento da doença periodontal (DP) em ratos. Trinta e seis animais foram divididos em Grupo Controle (C) que receberam oralmente soro fisiológico e Sinvastatina (S) que receberam oralmente Sinvastatina. Após 24 horas, a DP foi induzida utilizando-se um fio de algodão na região dento-gengival dos primeiros molares inferiores esquerdos. Após 7 dias, a ligadura foi removida e os animais receberam raspagem e alisamento radicular (RAR) e irrigação com soro fisiológico. Os animais foram eutanasiados aos 7, 15 e 30 dias. Radiograficamente, o tratamento com RAR mostrou uma menor perda óssea (PO) no Grupo S comparado ao C em todos os períodos. Concluiu-se que a Sinvastatina associada à RAR foi efetiva na redução da PO em ratos.

The study evaluated simvastatin in the treatment of periodontal disease (PD) in rats. 36 animals were divided into control group (C) receiving oral saline and Simvastatin (S) who received oral simvastatin. After 24 hours the PD was induced using a cotton yarn in the dento-gingival area of the first left molar. After 7 days the ligature was removed and animals received scaling and root planing (SRP) and irrigation with saline. The animals were sacrificed at 7, 15 and 30 days. Radiographically treatment with SRP showed less bone loss (BL) in the S group compared to C in all periods. It was concluded that SRP associated with simvastatin was effective in reducing the BL in rats.a

Ethanolic extract of Passiflora edulis Sims leaves inhibits protein glycation and restores the oxidative burst in diabetic rat macrophages after Candida albicans exposure

abstract This study was conducted to evaluate the effects of the ethanolic extract of Passiflora edulis leaves on blood glucose, protein glycation, NADPH oxidase activity and macrophage phagocytic capacity after Candida albicans exposure in diabetic rats. The Passiflora edulis Sims leaves were dried to 40°C, powdered, extracted by maceration in 70% ethanol, evaporated under reduced pressure and lyophilised. The biochemical tests performed were total phenolic content (TP) as determined by the Folin-Ciocalteu assay, trapping potential DPPH assay and total iron-reducing potential. Diabetes was induced by alloxan injection. Protein glycation was determined by AGE and fructosamine serum concentrations. Extract-treated diabetic animals demonstrated lower fructosamine concentrations compared with the diabetic group. Our results suggest that ethanolic Passiflora edulis Sims leaf extraction may have beneficial effects on diabetes and may improve glycaemic control in diabetic rats.

resumo O objetivo deste estudo foi avaliar os efeitos do extrato etanólico de folhas de Passiflora edulis sobre os níveis de glicose sanguínea, glicação protéica, produção de espécies reativas de oxigênio (ERO) e capacidade fagocítica de macrófagos de ratos diabéticos. As folhas de Passiflora edulis Sims foram secas a 40 °C, trituradas e o extrato preparado por maceração em solução hidroetanólica 70% (v/v) etanol foi evaporado sob pressão reduzida e liofilizado. Os testes químicos realizados demonstraram que além da presença de compostos fenólicos, determinada pelo método de Folin-Ciocalteu, o extrato apresentou potencial sequestrante de radicais DPPH e redutor de ferro. Nos animais diabéticos foi observado aumento na glicação protéica, avaliada pela concentração de frutosaminas e de produtos de glicação avançada (AGE), e redução na produção de ERO por macrófagos frente à Candida albicans, quando comparados ao grupo controle. O tratamento dos animais diabéticos com o extrato reduziu as concentrações de frutosaminas e manteve a produção de ERO em níveis semelhantes aos observados no grupo controle. Nossos resultados sugerem que o extrato etanólico de folhas de Passiflora edulis Sims pode apresentar efeitos benéficos sobre o diabetes e melhorar o controle glicêmico em ratos diabéticos.

Transgenic and conventional Brazilian soybeans don't cause or prevent preneoplastic colon lesions or oxidative stress in a 90-day in vivo study / Sojas transgênicas e convencionais brasileiras não causam ou previnem lesões pré-neoplásicas ou stress oxidativo em estudo in vivo de 90 dias

OBJECTIVE: The study presents the results of a 90-day safety assessment of rats fed with four varieties of soybeans, BRS 245 RR and BRS Valiosa RR (transgenic), BRS 133 and MG BR46 Conquista (non-transgenic). METHODS: Diets were prepared by incorporating toasted soybean flour to a commercial diet at 1%, 10% or 20% weight In the in vivo experimental the rats' body weight, body weight gain, food consumption, number of aberrant crypt foci, oxidative stress biomarkers, urea and creatinine levels were analyzed and compared between experimental groups, as well as histopathological observations (digestive tract, liver, kidneys). RESULTS: The results indicate that glyphosate-tolerant soy varieties neither induce nor prevent aberrant crypt foci induction, nor do their conventional counterparts. Similarly, none of the four soybean varieties tested induced changes in the digestive tract, liver or kidney. Serum biochemical parameters were also unchanged. CONCLUSION: The consumption of both, conventional and transgenic soybeans, were insufficient to ameliorate dimethylhydrazine-induced oxidative stress.

OBJETIVO: Este estudo apresenta os resultados de um experimento de 90 dias com o objetivo de avaliar a segurança de quatro variedades de grãos de soja: BRS 245 RR e BRS Valiosa RR (transgênicas), BRS 133 e MG BR46 Conquista (não transgênicas). MÉTODOS: As dietas foram preparadas incorporando farinha de grãos de soja à dieta comercial (FRI-LAB Ratos II) a 1%, 10% ou 20% m/m. O peso corpóreo dos animais, o ganho de peso, o consumo de dieta, o número de focos de criptas aberrantes e os níveis de marcadores de estresse oxidativo, de creatinina e de ureia foram comparados entre os grupos experimentais, assim como as observações histopatológicas (trato digestivo, fígado e rins). RESULTADOS: Os resultados indicaram que as variantes glifosato-tolerantes não induziram ou preveniram a indução de focos de criptas aberrantes, assim como suas parentais convencionais. Similarmente, nenhuma das quatro variedades de grãos de soja testadas induziu alterações no trato digestivo, no fígado e nos rins. Os parâmetros bioquímicos do soro permaneceram também inalterados. CONCLUSÃO: Tanto o consumo de grãos de soja convencionais quanto o de transgênicos foram ineficazes para melhorar os níveis de estresse oxidativo induzidos pela dimetilhidrazina.

Development of low-calorie guava preserves with prebiotics and evaluation of their effects on carcinogenesis biomarkers in rats.

Faced with the search for healthy products that provide additional benefits to consumers' health, the main objectives of this work were to develop a low-calorie preserve containing prebiotics (lactulose and polydextrose) and to evaluate the effects of these prebiotics on oxidative stress and colon carcinogenesis in male rats treated with 1,2-dimethylhydrazine (DMH). A total of 62.5% w/w of the sucrose in conventional preserves was replaced by polydextrose, and lactulose was added at 0%, 16%, 19.5% or 23% w/w concentrations. The acceptance of these four low-calorie guava preserve samples and the conventional sample was equal (P>0.05), with a score of 6.49. The level of degradation of lactulose was low (18.45 g100 g(-1)lactulose), ensuring that even at a lower concentration of this prebiotic (16% w/w), the concentration remained above the minimum level considered functional. We found that consumption of the low-calorie preserves with prebiotics does not have an effect on the development of mucin-negative ACF and classical ACF in the initiation phase of the mutagenic process. However, the consumption of 1.5 g of the preserve/rat/day potentiated lipid peroxidation and proteic oxidation in the liver.

Organic and conventional Coffea arabica L.: a comparative study of the chemical composition and physiological, biochemical and toxicological effects in Wistar rats.

Differentiation between organic and conventional coffee has increased due to the growing demand and high consumption of healthy foods that contain compounds with antioxidant potential, which have been associated with the reduction of chronic diseases. We used organic and conventional coffee in powder 4% (w/w) and infusions 5%, 10% and 20% (w/v) incorporated in a commercial diet to test in vivo. The levels of chlorogenic acid, caffeine and trigonelline were determined by high performance liquid chromatography. The body weight, weight gain, food consumption, aberrant foci crypt, mucin depleted foci, stress biomarkers protein carbonyl and malondialdehyde, biochemical parameters and behavior of the rats were compared between the experimental and control groups within a framework of colon carcinogenesis. The organic coffee showed higher levels of chlorogenic acid, caffeine and trigonelline than conventional, however, this difference did not significantly affect behavior. The infusions had an antioxidant effect, reducing the levels of malondialdehyde; however, the biochemical parameters of the serum were not altered, and there was neither induction nor prevention of preneoplasic lesions.

Evaluation of a simple and low cost potentiometric biosensor for pharmaceutical and in vivo adrenaline determination.

In this work the polyphenol oxidase (PPO) was the main component of a biosensor for adrenaline determination. The activity of this enzyme was measured in several vegetables. Banana (Musa sp.) extracts presented better results with 974 UA (units of activity). The biosensor was constructed with a polyethylene tube (0.8 mm i.d.) filled with: carbon paste containing 50 UA of the PPO in phosphate buffer (pH=7.00) solution and vaseline as agglutinant. When the biosensor was applied in medicine samples it provided a linear range from 8.00×10(-9) to 8.00×10(-4) mol L(-1); the results obtained with the proposed method and the Brazilian Pharmacopoeia method were in agreement (t-test). When it was applied in blood samples, the matrix-matching calibration was used, and the linear range was from 8.00×10(-7) to 8.00×10(-3) mol L(-1). In vivo studies were also done. The obtained results for those electrodes, which were inserted in the jugular vein of Wistar rats, were very promising.

Oxidative stress in alcohol-induced rat parotid sialadenosis.

This study evaluated the effect of chronic ethanol consumption on the oxidative status of rat parotid and submandibular glands. To identify the endogenous response to ethanol ingestion, the activities of the antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) were determined. In addition, the antioxidant alpha-tocopherol was supplied to the animals in order to estimate its action in ethanol-associated glandular damage. The thiobarbituric acid reactive substances (TBARS), and the protein carbonyl (PC) content, both markers of cellular oxidative stress on lipid and protein structures, respectively, were recorded. Animals subjected to alcohol ingestion showed a low body growth rate with concomitant enlargement of absolute and relative parotid wet weight, compared with pair-fed calorie-controlled rats. Parotid glands of ethanol-treated animals showed increased SOD and GPx activity, and alpha-tocopherol was able to reduce their activities to the control levels. TBARS and PC were enhanced after chronic ethanol treatment in rat parotids. Supplemental alpha-tocopherol suppressed the oxidative ethanol-induced damage in lipid without affecting induced protein oxidation. Submandibular glands revealed no alterations in the weight, enzymatic and oxidative parameters tested due to ethanol and/or alpha-tocopherol ingestion. These findings indicate the involvement of oxidative stress in parotid gland sialadenosis due to ethanol consumption and the capability of alpha-tocopherol to halt lipid damage, although this low-molecular antioxidant compound leads to neither increased glandular weight nor protein oxidation in ethanol-induced parotid alterations.

Estudo do processo de S-glutationação protéica no ®BURST¼ respiratório de leucócitos: modulação pela lactona sesquiterpênica licnofolido / Process of protein S-glutathionylation study on the respiratory burst of leukocytes: sesquiterpene lactone lychnopholide modulation

Foi estudado o efeito da lactona sesquiterpênica licnofolido sobre o ®burst¼ respiratório de leucócitos polimorfonucleares inflamatórios (PMN) estimulados por forbol (PMA), pelo peptídeo quimiotático fMLP ou zimozan opsonizado (OZ). O licnofolido inibiu de forma dose-dependente a liberação de `O IND. 2 POT. PONTO -´ pelos PMN, sem alteração do período ®lag¼ do complexo NADPH oxidase. O efeito foi mais acentuado quando os PMN foram estimulados diretamente pela via de proteína quinase C. A adição de ditiotreitol ou glutationa reduzida (GSH) às suspensões celulares antes da incubação com licnofolido preveniu parcialmente o efeito inibitório. O tratamento dos PMN com a lactona determinou uma queda drástica dos níveis celulares de GSH livre, sem incremento de glutationa oxidada (GSSG)...

Sesquiterpene lactone from Wunderlichia crulsiana inhibits the respiratory burst of leukocytes triggered by distinct biochemical pathways.

The sesquiterpene lactone tubiferin was chemically purified from the brazilian native plant Wunderlichia crulsiana and identified by NMR and GC/MS data. Its ability to inhibit the respiratory burst of peritoneal inflammatory polymorphonuclear leukocytes (PMN) stimulated upon addition of phorbol miristate acetate (PMA), opsonized zymosan (OZ), and N-formyl-methionyl-leucyl-phenylalanine (fMLP) was evaluated. The tubiferin inhibition was more pronounced when PMN were stimulated through the protein kinase C pathway (PMA) compared to the alternative complement pathway (OZ). The inhibition when PMN were triggered by a chemoattractant stimulus (fMLP) was similar to that achieved with OZ-stimulated phagocytes. Tubiferin showed dose-dependent effects on the PMN respiratory burst triggered by the three different substances, and also decreased substantially the carrageenan-induced mice paw edema.