Aloe vera na criopreservação do sêmen de tambaqui (Colossoma macropomum) / Aloe vera in the cryopreservation of tambaqui (Colossoma macropomum) sperm

This study aimed to evaluate the extract of Aloe vera (AV) associated or not with 10% Dimethylsulfoxide (DMSO) in cryopreservation of tambaqui semen. For the formation of the pools (n= 14), 30 males were hormonally induced twice. Each pool had the objective motility, curvilinear velocity, straight-line velocity, average path velocity and morphology analyzed before and after cryopreservation of semen. The means for cryopreservation were constituted of Powder Coconut Water-104 diluent added DMSO and/or AV (5 or 10%). After cryopreservation, motility, velocities and morphology were reduced significantly when compared to fresh semen. For sperm motility the best treatment was that using only DMSO (20,86±8,31) and DMSO + 5% AV (15.71±9.77). For the velocities, the worse treatment was DMSO+10% AV. Treatment with only the addition of DMSO had a significantly higher effect than others on percentage of morphologically normal sperm. The mean correlation found was between motilityand the rate of morphologically normal sperm (r = 0.687). In conclusion, the addition of AV does not provide greater protection for spermatozoa during cryopreservation.

Antimicrobial activity of ß-lapachone encapsulated into liposomes against meticillin-resistant Staphylococcus aureus and Cryptococcus neoformans clinical strains.

The aim of this study was to determine whether encapsulation of ß-lapachone (ß-lap) into liposomes interferes with its in vitro antimicrobial activity against meticillin-resistant Staphylococcus aureus (MRSA) and Cryptococcus neoformans clinical strains. Liposomes (ß-lap:lipo or ß-lap:HPß-CD-lipo) were prepared using the hydration of thin lipid film method followed by sonication. The in vitro antimicrobial activities of ß-lap-loaded liposomes against MRSA and C. neoformans were evaluated using the microdilution method according to the Clinical and Laboratory Standards Institute (CLSI). The liposomes presented a mean particle size ranging from 88.7±1.5nm to 112.4±1.9nm with a polydispersity index ranging from 0.255 to 0.340, zeta potential from -0.26±0.01mV to +0.25±0.05mV and drug encapsulation efficiency from 97.4±0.3% to 98.9±0.4%. ß-Lap and ß-lap:HPß-CD had minimum inhibitory concentrations (MICs) ranging from 2mg/L to 4mg/L, whereas the MICs of ß-lap-lipo or ß-lap:HPß-CD-lipo ranged from 4mg/L to 16mg/L for the MRSA strains tested. ß-Lap and ß-lap:HPß-CD were able to inhibit fungal growth [MIC=2-8mg/L and minimum fungicidal concentration (MFC)=4-8mg/L]. However, ß-lap-lipo and ß-lap:HPß-CD-lipo were more efficient, with MICs and MFCs of <4mg/L. These findings suggest that the liposomal formulations tested do not interfere significantly with ß-lap antibacterial activity against MRSA and improve its antifungal properties against C. neoformans.

Encapsulation of trans-dehydrocrotonin in liposomes: an enhancement of the antitumor activity.

The aim of this study was the encapsulation of trans-dehydrocrotonin (t-DCTN) and its inclusion complexes with hydropropyl-beta-cyclodextrin (HP-beta-CD) in liposomes to improve t-DCTN antitumor activity. The in vitro kinetic profiles of t-DCTN-loaded liposomes (LD) and t-DCTN:HP-beta-CD-loaded liposomes (LC) were evaluated using the dialysis technique. The antitumor activity of LD and LC were investigated against Sarcoma 180 in Swiss mice. Histopathological and hematological analyses were carried out. The amounts of t-DCTN and t-DCTN:HP-beta-CD inclusion complex encapsulated in liposomes were equivalent to 1 mg of t-DCTN. The encapsulation efficiencies of LD and LC were 95.0 +/- 3.8% and 91.1 +/- 5.6%, respectively. In relation to kinetics, the drug release profiles of t-DCTN are in substantial agreement with the Fickian model. The treatment of animals with LD and LC produced tumor inhibitions of 79.4 +/- 9.6% and 63.5 +/- 5.5%, respectively. The liposomal encapsulation of t-DCTN by entrapment in the phospholipid bilayer increased at twice the antitumor activity. Moreover, the liposomal formulations reduced the hepatotoxicity effect of the drug and no significant hematological toxicity was observed in the treated animals. However, the counting of platelets was slightly decreased. Thus, the results show that the development of liposomal formulations containing t-DCTN or t-DCTN:HP-beta-CD is an important advance for enabling this drug to be use in therapy.

Genotoxicity and antigenotoxicity of cashew (Anacardium occidentale L.) in V79 cells.

The use of plants for the treatment of diseases continues to rise although there are few studies providing proof of these effects. One of these plants is the Anacardium occidentale, popularly known as the cashew. The present study evaluated the possible genotoxic and protective activities of cashew stem bark methanolic extract, in vitro, using methyl methanesulfonate (MMS) as a positive control, to compare possible mechanisms of DNA damage induction in the Comet assay. The antigenotoxicity protocols used were pre, simultaneous and post-treatment in relation to MMS. In genotoxicity and antigenotoxicity assessments, besides MMS, PBS was used as the negative control and three concentrations of the A. occidentale extract (500 microg/mL, 1000 microg/mL and 2000 microg/mL) were used on Chinese hamster lung fibroblasts (V79 cells). The Comet assay revealed that the two lowest concentrations tested presented no genotoxic activity, whereas the highest presented genotoxicity. All of the concentrations showed protective activity in simultaneous and post-treatment in relation to MMS. Further studies are required to identify the substances that comprise the extract and more clearly comprehend the antigenotoxic mechanism detected in this study.

Avaliação da qualidade de vida pos-cirurgia cardiaca na fase I da reabilitação atraves do questionario MOS SF-36 / Quality of life assessment following heart surgery, during phase I reabilitation, Through MOS SF-36 questionnarie

O questionario de qualidade de vida Medical Outcome Study Short From -36 (MOS SF-36) permite monitorar condicao de saude antes e apos o tratamento instituido, sendo sencivel a melhora clinica. O objetivo desse estudo foi avaliar a qualidade de vida de pacientes submetidos a cirurgia de revascularizacao do mocardio e que participaram de um programa de reabilitacao cardiaca, atraves da aplicacao do questionario MOS SF-36. Metodologia: foram incluidos nesse estudo 24 individuos de ambos os sexos (15 homens e 9 mulheres) na faixa etaria entre 23 e 77 anos (idade media 58+-6 anos) submetidos a cirurgia de revascularizacao do miocardio, com quadro clinico estavel e que participem de uma programa de reabilitacao cardiaca fase I. O questionario foi aplicado em tres momentos antes, no 5º dia do pos-operatorio e 2 meses apos a cirurgia. Para analise estatistica foi utilizado o teste de wilcoxon para amostras pareadas. Resultados Observou-se queda dos seguintes parametros Funcionamento do Organismo (p=0,000), Limitacao por Disturbios fisicos (p=0,002), vitalidade (p=0,003) e dor (p=0,000) apos a cirurgia, havenso recuperacao significativa 2 meses apos (p=0,008, p=0,000,p=0,000 e p=0,000 respectivamente).Este estudo sugere que o questionario MOS SF-36 permite avaliar os beneficios da reabilitacao cardiaca fase I a qual propocionou autoconfianca e retorno as atividades diarias

Investigations on the antinociceptive activity of crude extracts from Croton cajucara leaves in mice.

The crude leaf extracts of Croton cajucara Benth. were studied for their antinociceptive property in chemical and thermal models of nociception in mice. All the tested extracts (hexanic, chloroformic and methanolic), at oral doses of 100 and 200 mg/kg demonstrated significant inhibition of acetic acid-induced writhing and the second phase response of formalin, but did not manifest a significant effect in hot-plate test.

Effect of trans-dehydrocrotonin, a 19-nor-clerodane diterpene from Croton cajucara on experimental hypertriglyceridaemia and hypercholesterolaemia induced by Triton WR 1339 (tyloxapol) in mice.

The effect of trans-dehydrocrotonin (t-DCTN) from Croton cajucara Benth. was investigated in mice on Triton WR 1339 (tyloxapol)-induced hypercholesterolaemia and hypertriglyceridaemia. Mice treated with single application of tyloxapol (400 mg/kg, i.p.) demonstrated significantly increased blood levels of total cholesterol and triglycerides at 24 h and 48 h after its injection, compared to normal controls. These increases were found to be markedly suppressed in animals treated orally with 25 and 50 mg/kg t-DCTN or 100 mg/kg gemfibrozil, an established antihypercholesterolaemic drug. These results suggest that t-DCTN may be a suitable candidate for combating pathologies associated with hyperlipaemia.

Antigenotoxicity of trans-dehydrocrotonin, a clerodane diterpene from Croton cajucara.

The antigenotoxic action of three doses of trans-dehydrocrotonin (t-DCTN), the active ingredient obtained from the bark extract of Croton cajucara, a plant native to the Amazon, was determined in Swiss mice in vivo. Mice were submitted to acute intraperitoneal and gavage treatments, then their bone marrow cells were subsequently analyzed by micronucleus (MN) and chromosome aberration (CA) assays. Comparisons were performed between the three doses of t-DCTN and the negative-control group. Statistical analysis indicated that doses of 50 and 75 % of the LD(50), via intraperitoneal treatment or gavage injection, were antimutagenic with regard to cyclophosphamide. However, the dose of 25 % of the LD(50) was only antimutagenic when administered by gavage. Based on these observations, it can be suggested that gavage is the most effective method of administering t-DCTN. In addition, t-DCTN showed no cytotoxic effects in the bone marrow cells regardless of the route of exposure.

The lipid-lowering effect of trans-dehydrocrotonin, a clerodane diterpene from Croton cajucara Benth. in mice fed on high-fat diet.

The clerodane diterpene trans-dehydrocrotonin extracted and isolated from the stem bark of Croton cajucara Benth. was investigated for its lipid-lowering effect in mice fed on a high-fat diet. Mice fed on a high-fat diet for a two-week period demonstrated significantly increased blood levels of total cholesterol and triglycerides, compared with normal controls. Oral treatment with trans-dehydrocrotonin at a dose of 25 or 50 mg kg(-1) daily markedly suppressed the high-fat-diet associated rise in total cholesterol and triglyceride levels. The hypocholesterolaemic effect of trans-dehydrocrotonin was more prominent at the dose of 50 mg kg(-1) with significant decreases in high-density lipoprotein, very-low-density lipoprotein and low-density lipoprotein cholesterol levels. The lower atherogenic index of the trans-dehydrocrotonin-treated groups suggests the hypolipidaemic potential of this plant-based drug. These results indicate that orally administered trans-dehydrocrotonin is effective in suppressing high-fat-diet-induced hyperlipidaemia in mice and suggest its likely beneficial use as anti-atherogenic agent.

Blood glucose- and triglyceride-lowering effect of trans-dehydrocrotonin, a diterpene from Croton cajucara Benth., in rats.

AIM: The objective of this study was to assess in rats the antidiabetic effects (i.e. reduction of hyperglycaemia and hypertriglyceridaemia) of trans-dehydrocrotonin (t-DCTN), a bioactive diterpene isolated from the popular medicinal plant Croton cajucara. METHODS: Hyperglycaemia was induced by intraperitoneal injection of streptozotocin (STZ) and hypertriglyceridaemia by oral administration of ethanol in rats. The blood glucose levels were measured by the glucose oxidase method using commercially available enzyme kits. RESULTS: Treating rats with t-DCTN (50 mg/kg) significantly reduced STZ-induced increases in blood glucose levels as well as ethanol-induced increases in blood triglycerides. CONCLUSION: The results suggest that t-DCTN has an antidiabetic potential that warrants further research on its mechanism and clinical significance.

Ethnopharmacology, phytochemistry and pharmacology: a successful combination in the study of Croton cajucara.

Phytochemical and pharmacological studies of Croton cajucara were oriented by traditional medicine. The stem bark of the mature plant is a rich source of clerodane-type diterpenes: trans-dehydrocrotonin (DCTN), trans-crotonin (CTN), cis-cajucarin B, cajucarin A, cajucarinolide and two novel clerodanes, trans-cajucarin B and sacacarin. In young (18-month-old) plants, the triterpene acetyl aleuritolic acid (AAA) was the major stem bark component and in these the diterpene DCTN was not present. The highest concentration of DCTN (1.4% of dry bark) was detected in 4-6 year-old plants, while 3-year-old plants contained only 0.26% of this diterpene. Three steroids (beta-sitosterol, stigmasterol and sitosterol-3-O-beta-glucoside), two flavonoids (kaempferol 3,4', 7-trimethyl ether and 3,7-dimethyl ether) and one diterpene (cajucarinolide) were isolated from the leaves of this Croton. The main pharmacological activity was correlated with DCTN. This clerodane produced anti-inflammatory and antinociceptive effects and a significant hypoglycemia in alloxan-induced diabetic rats. The compound also reduced the index of gastric lesions induced by restraint-in-cold. Dose-related DCTN and CTN inhibited in vivo the basal acid secretion in pylorus-ligature rats and oxyntic glands isolated from rabbit gastric mucosa, DCTN, CTN or AAA decreased in vitro uptake basal acid secretion induced by histamine and measured with the 14C-aminopyrine uptake method. Uniquely DCTN inhibited 14C-AP uptake induced by bethanechol. The terpenoids, DCTN and AAA, and the chloroform extract of 6-month-old plants reduced gastrointestinal transit in mice. The effects of DCTN and CTN on the survival of mice bearing Sarcoma 180 and Ehrlich carcinoma ascitic tumors, on the proliferation of cultured cells and TNFalpha were determined. DCTN was also evaluated for a possible antioestrogenic activity using the immature rat as a model system for bioassay of oestrogen and for an anti-implantation effect in regularly cycling rats. The biological experiments, using the plant extracts and the terpenoids DCTN, CTN and AAA, are herein discussed.

Antioestrogenic effect of trans-dehydrocrotonin, a nor-clerodane diterpene from Croton cajucara Benth. in rats.

This study examined trans-dehydrocrotonin (t-DCTN), a nor-clerodane diterpene isolated from the Brazilian medicinal plant Croton cajucara Benth., for a possible antioestrogenic activity using immature rats as a model system for bioassay of oestrogen, and for an antiimplantation effect in regularly cycling rats of proven fertility. In the antioestrogen test, t-DCTN (25 and 50 mg/kg) effectively prevented oestrogen-induced increases of uterine wet weights. In addition, the vaginal openings provoked by oestrogen were completely prevented by t-DCTN. However, blastocyst-implantation was only insignificantly affected in t-DCTN pretreated animals. These results suggest that t-DCTN may be an antioestrogen and warrants further studies with regard to its mechanism of action.

Investigation of genotoxic activity of trans-dehydrocrotonin, a clerodane diterpene from Croton cajucara.

The genotoxic action of three doses of trans-dehydrocrotonin (t-DCTN), an active ingredient obtained from the bark extracts of an Amazon native plant, Croton cajucara, were examined in Swiss mouse bone marrow cells in vivo, submitted to acute intraperitoneal treatment, by micronucleus (MN) and chromosomal aberration (CA) tests. The statistical tests (Anova and Tukey) made to compare the results obtained in each of the three doses of t-DCTN with the negative-control group showed that the frequencies of MN and mitotic index were equal to the negative-control and that the frequencies of CA were lower than that observed in the negative-control. Therefore, based on our results it can be said that t-DCTN is not genotoxic nor cytotoxic to mouse bone marrow cells, submitted to acute intraperitoneal treatment in vivo. Teratogenesis Carcinog. Mutagen. 19:377-384, 1999.

Anti-tumour activity of two 19-nor-clerodane diterpenes, trans-dehydrocrotonin and trans-crotonin, from Croton cajucara.

The effects of two nor-diterpenes, trans-dehydrocrotonin (DCTN) and trans-crotonin (CTN) from Croton cajucara (Euphorbiaceae), on the survival of mice bearing Sarcoma 180 and Ehrlich carcinoma ascitic tumours, on the proliferation of cultured Ehrlich cells and TNF alpha activity were determined. When the mice were treated with 80 and 120 mg/kg of DCTN or 38 mg/kg of 5-FU a significant anti-tumour activity was obtained (%T/C of 128-140). The cytotoxicity against Ehrlich carcinoma was 16 microM for DCTN and CTN whereas the flavonoid quercetin was cytotoxic at 44 microM in 48 h cell culture. No apoptosis was seen on in vitro electrophoresis of DNA extracted from the tumour cells treated with DCTN and CTN. A significant TNF alpha activity was detected in Ehrlich tumour-bearing mice treated with DCTN suggesting an enhanced immune function.

T-lymphocytes from individuals with filarial inflammatory disease have increased transendothelial migration in vitro.

The in vitro transendothelial migration of circulating filarial antigen-specific T-cells was examined in Wuchereria banerofti infection. Circulating T-cells from individuals with filaria-induced lymphatic pathology (LP) had significantly greater migration through unstimulated HUVEC monolayers than did T-cells from asymptomatic infected (MF) individuals (P = 0.04). In contrast to the MF individuals where no effect was seen, transendothelial migration of 48-hr filarial antigen stimulated T-cells from LP individuals was significantly (P = 0.01) greater than migration of 48-hr media-stimulated T-cells. In six of seven patients examined, inhibition of the VLA-4/VCAM-1 pathway resulted in greater than 50% inhibition of transendothelial migration of T-cells.

Hypoglycemic effect of trans-dehydrocrotonin, a nor-clerodane diterpene from Croton cajucara.

trans-Dehydrocrotonin (t-DCTN), a 19-nor-clerodane diterpene isolated from the bark of Croton cajucara Benth. (Euphorbiaceae) demonstrated a significant hypoglycemic activity in alloxan-induced diabetic rats but not in normal rats, at oral doses of 25 and 50 mg/kg body weight. The drug also effectively lowered the blood sugar levels in glucose fed normal rats. The hypoglycemic effect of t-DCTN was almost comparable to that produced by glibenclamide (2 mg/kg), a clinically useful drug. The results indicate the antihyperglycemic potential of t-DCTN.

Investigation of anti-inflammatory and antinociceptive activities of trans-dehydrocrotonin, a 19-nor-clerodane diterpene from Croton cajucara. Part 1.

The anti-inflammatory and antinociceptive effects of trans-dehydrocrotonin, isolated from the bark of Croton cajucara (Euphorbiaceae), were investigated using several animal models. The trans-dehydrocrotonin produced a significant inhibition of carrageenin-induced paw edema and cotton pellet granuloma in rats. It also inhibited the writhings in mice induced by acetic acid, but did not show a significant effect in the hot-plate test in mice. The LD50 of t-DCTN was 555.0 mg/kg (p.o.) for mice.

The presence or absence of active infection, not clinical status, is most closely associated with cytokine responses in lymphatic filariasis.

Twenty-eight Brazilians from an area in which Wuchereria bancrofti is endemic were classified as asymptomatic microfilaremic or having clinical filariasis with active infection or without current active infection. Total accumulation of antigen-specific interleukin (IL)-4 and IL-5 in 48 h peripheral blood mononuclear cell supernatants was not significantly different between groups. However, when cytokine kinetics were examined, responses segregated according to infection status. Sustained production of IL-4 and IL-5 beyond the first 24 h of stimulation and production of interferon-gamma were seen only in the group with clinical filariasis without active infection. CD8 T cells were the major source of IL-5 production in this group, while CD8 production of IL-5 was undetectable in any subject with active infection (asymptomatic microfilaremic or with clinical filariasis and active infection). These findings indicate that active infection, rather than clinical status, is most closely associated with cytokine patterns in lymphatic filariasis.