N-Methyl-(2S,4R)-trans-4-hydroxy-L-proline isolated Sideroxylon obtusifolium attenuates TPA-induced irritant contact dermatitis in mice.

Dermatitis is defined as a set of inflammatory diseases that affect the skin, with varied causes. Among the different types of dermatitis, contact dermatitis is the most prevalent. Although the current therapy is often effective, it is associated with adverse effects and the possibility of drug tolerance. N-Methyl-(2S, 4R)-trans-4-hydroxy-L-proline is a L-proline amino acid derivative found in the leaves of Sideroxylon obtusifolium, a species traditionally used to treat inflammatory diseases. The aim of this study was to investigate the topical anti-inflammatory effect of N-methyl-(2S, 4R)-trans-4-hydroxy-L-proline (NMP) in 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced irritant contact dermatitis in mice. Topically administered NMP, at doses of 0.03 - 0.50 mg/ear, reduced TPA-induced ear edema and neutrophil migration, as evidenced by low tissue myeloperoxidase activity and verified by histological examination. In addition, NMP (0.06 mg/ear) reduced tissue levels of pro-inflammatory cytokines (TNF-α, IL-6, IL-1ß, INF-γ and MCP-1) and of the anti-inflammatory cytokine IL-10, and reduced gene expression of TNF-α, IL-6 and IL-1ß increased by TPA. The data suggest that N-methyl-(2S, 4R)-trans-4-hydroxy-L-proline acts as a topical anti-inflammatory agent that decreases the expression of inflammatory cytokines, making it useful for the treatment of skin inflammation. Further investigations are necessary for its development as a therapeutic agent.

Antidiabetic, Antiglycation, and Antioxidant Activities of Ethanolic Seed Extract of Passiflora edulis and Piceatannol In Vitro.

The objective of this work was to investigate the antidiabetic, antiglycation, and antioxidant potentials of ethanolic extract of seeds of Brazilian Passiflora edulis fruits (PESE), a major by-product of the juice industry, and piceatannol (PIC), one of the main phytochemicals of PESE. PESE, PIC, and acarbose (ACB) exhibited IC50 for alpha-amylase, 32.1 ± 2.7, 85.4 ± 0.7, and 0.4 ± 0.1 µg/mL, respectively, and IC50 for alpha-glucosidase, 76.2 ± 1.9, 20.4 ± 7.6, and 252 ± 4.5 µg/mL, respectively. The IC50 of PESE, PIC, and sitagliptin (STG) for dipeptidyl-peptidase-4 (DPP-4) was 71.1 ± 2.6, 1137 ± 120, and 0.005 ± 0.001 µg/mL, respectively. PESE and PIC inhibited the formation of advanced glycation end-products (AGE) with IC50 of 366 ± 1.9 and 360 ± 9.1 µg/mL for the initial stage and 51.5 ± 1.4 and 67.4 ± 4.6 µg/mL for the intermediate stage of glycation, respectively. Additionally, PESE and PIC inhibited the formation of ß-amyloid fibrils in vitro up to 100%. IC50 values for 1,1-diphenyl-2-picrylhydrazyl radical (DPPH•) scavenging activity of PESE and PIC were 20.4 ± 2.1, and 6.3 ± 1.3 µg/mL, respectively. IC50 values for scavenging hypochlorous acid (HOCl) were similar in PESE, PIC, and quercetin (QCT) with values of 1.7 ± 0.3, 1.2 ± 0.5, and 1.9 ± 0.3 µg/mL, respectively. PESE had no cytotoxicity to the human normal bronchial epithelial (BEAS-2B), and alpha mouse liver (AML-12) cells up to 100 and 50 µg/mL, respectively. However, 10 µg/mL of the extract was cytotoxic to non-malignant breast epithelial cells (MCF-10A). PESE and PIC were found to be capable of protecting cultured human cells from the oxidative stress caused by the carcinogen NNKOAc at 100 µM. The in vitro evidence of the inhibition of alpha-amylase, alpha-glucosidase, and DPP-4 enzymes as well as antioxidant and antiglycation activities, warrants further investigation of the antidiabetic potential of P. edulis seeds and PIC.

Increased Oxidative Stress in Gastric Cancer Patients and Their First-Degree Relatives: A Prospective Study from Northeastern Brazil.

BACKGROUND AND AIMS: First-degree relatives of gastric cancer patients are at increased risk of developing gastric cancer. Increased oxidative stress, including lipid peroxidation, has been associated with gastric carcinogenesis. Whether first-degree relatives of gastric cancer patients have increased oxidative stress remains unknown. We aimed to compare oxidative stress in patients with gastric cancer, their first-degree relatives, and dyspeptic controls. METHODS: A total of 155 patients undergoing upper endoscopy were prospectively enrolled, including 50 with gastric cancer, 49 first-degree relatives of gastric cancer patients, and 56 controls. Serum concentrations of malondialdehyde (MDA) and glutathione) and activities of superoxide dismutase (SOD) and catalase were measured. Multivariate analysis adjusting for sex, age, smoking status, and alcohol consumption was performed. RESULTS: Lipid peroxidation, as measured by concentration of MDA (nmol/mL), was higher (p = 0.04), and glutathione levels were lower (p < 0.001) in the gastric cancer group compared to controls. There was no difference in the catalase activity among the groups. There was no difference in glutathione and MDA concentration or catalase activity between the different stages of gastric cancer based on the TNM classification. Relatives of gastric cancer patients had higher glutathione concentration (µmol/mL) compared to gastric cancer patients (262.5 vs. 144.6; p = 0.018), while there was no difference in MDA concentration. Catalase and superoxide dismutase activity were lower in the gastric cancer group (3.82 vs. 0.91; p < 0.001 and 1.04 vs. 0.6; p < 0.001) compared to their first-degree relatives. Interestingly, MDA concentration in the first-degree relative group was higher than in the control group (7.9 vs. 5.1; p = 0.03). CONCLUSIONS: In this study, similarly to gastric cancer patients, their first-degree relatives were found to have increased oxidative stress compared to controls. Further studies are warranted to validate this observation and to better understand the role of oxidative stress as a possible biomarker in this population.

Methylmercury chronic exposure affects the expression of DNA single-strand break repair genes, induces oxidative stress, and chromosomal abnormalities in young dyslipidemic APOE knockout mice.

Mercury (Hg) is one of the most toxic environmental pollutants, especially when methylated, forming methylmercury (MeHg). MeHg affects DNA repair, increases oxidative stress, and predisposes to cancer. MeHg neurotoxicity is well-known, but recently MeHg-associated cardiovascular effects were recognized. This study evaluated circulating lipids, oxidative stress, and genotoxicity after MeHg-chronic exposure (20 mg/L in drinking water) in C57BL/6J wild-type and APOE knockout (ko) mice, the latter, being spontaneously dyslipidemic. Experimental mice were assigned to four groups: non-intoxicated and MeHg-intoxicated wild-type mice and non-intoxicated and MeHg-intoxicated APOE ko mice. Plasma levels of triglycerides, total cholesterol (TC), HDL, and LDL were analyzed. Liver lipid peroxidation and splenic gene expression of xeroderma pigmentosum complementation groups A, C, D, and G (XPA, XPC, XPD, and XPG), X-ray repair cross-complementing protein 1 (XRCC1), and telomerase reverse transcriptase (TERT) were measured. Fur Hg levels confirmed chronic MeHg intoxication. MeHg exposure raises TC levels both in wild-type and APOE ko mice. HDL and LDL-cholesterol levels were increased only in the MeHg-challenged APOE ko mice. MeHg increased liver lipid peroxidation, regardless of the genetic background. Unintoxicated APOE ko mice showed higher expression of TERT than all other groups. APOE deficiency increases XPA expression, regardless of MeHg intoxication. Furthermore, MeHg-intoxicated mice had more cytogenetic abnormalities, effect which was independent of APOE deficiency. More studies are needed to dissect the interactions between circulating lipids, MeHg intoxication, and DNA-repair pathways even at young age, interactions that likely play critical roles in cell senescence and the risk for chronic disorders later in life.

Oral methylmercury intoxication aggravates cardiovascular risk factors and accelerates atherosclerosis lesion development in ApoE knockout and C57BL/6 mice.

Methylmercury (MeHg) intoxication is associated with hypertension, hypercholesterolemia, and atherosclerosis by mechanisms that are not yet fully understood. We investigated the effects of MeHg intoxication in atherosclerosis-prone (ApoE-KO) and resistant C57BL/6 mice. Mice were submitted to carotid stenosis surgery (to induce atherosclerosis faster) and received water or MeHg solution (20 mg/L) for 15 days. Tail plethysmography was performed before and after MeHg exposure. Food and MeHg solution intakes were monitored weekly. On the 15th day, mice were submitted to intravital fluorescence microscopy of mesenteric vasculature to observe in vivo leukocyte rolling and adhesion. Results showed that despite the high hair and liver Hg concentrations in the MeHg group, food and water (or MeHg solution) consumption and liver function marker levels were similar to those in controls. MeHg exposure increased total cholesterol, the atherogenic (non-HDL) fraction and systolic and diastolic blood pressure. MeHg exposure also induced inflammation, as seen by the increased rolling and adhered leukocytes in the mesenteric vasculature. Atherosclerosis lesions were more extensive in the aorta and carotid sites of MeHg-ApoE knockout mice. Surprisingly, MeHg exposure also induced atherosclerosis lesions in C57BL/6 mice, which are resistant to atherosclerosis formation. We concluded that MeHg intoxication might represent a risk for cardiovascular diseases since it accelerates atherogenesis by exacerbating several independent risk factors.

(-)-Myrtenol accelerates healing of acetic acid-induced gastric ulcers in rats and in human gastric adenocarcinoma cells.

The gastroprotective property of (-)-myrtenol, a monoterpenoid, has been demonstrated previously against acute gastric ulceration induced by ethanol. However, the healing property of (-)-myrtenol in a chronic gastric ulcer model remains to be verified. This study evaluated its healing efficacy and the mechanism involved using the rat model of chronic gastric ulcer induced by serosal injection of 80% acetic acid in vivo, and human gastric adenocarcinoma cells (AGS) in vitro. The results showed that compared to vehicle-treated ulcer controls, oral administration of (-)-myrtenol (50 and 100 mg/kg/day) for 7 days promoted ulcer healing, as indicated by significant decreases in ulcer area and volume. The macroscopic and microscopic findings confirmed the healing potential of (-)-myrtenol. The ulcer healing activity was also associated with significant increases in gastric mucin content, collagen deposition, number of cells with positive marking for proliferating cell nuclear antigen (PCNA), and by changes in the expression of the inflammatory parameters tumor necrosis factor (TNF)-α, interleukin (IL)-1ß and cyclooxygenase (COX)-2, as well as a decrease of metalloproteinases (MMP-9 and MMP-2) activity. Furthermore, in vitro assays using the AGS cultures revealed that (-)-myrtenol favors wound healing activity via stimulation of cell proliferation and migration without altering the cell viability. Taken together, these findings indicate that (-)-myrtenol has gastro-cytoprotective and ulcer healing properties that can be further explored to develop a new therapeutic agent from a natural source for the treatment of gastric ulcer.

Peripheral antinociceptive action of mangiferin in mouse models of experimental pain: role of endogenous opioids, K(ATP)-channels and adenosine.

This study aimed to assess the possible systemic antinociceptive activity of mangiferin and to clarify the underlying mechanism, using the acute models of chemical (acetic acid, formalin, and capsaicin) and thermal (hot-plate and tail-flick) nociception in mice. Mangiferin at oral doses of 10 to 100 mg/kg evidenced significant antinociception against chemogenic pain in the test models of acetic acid-induced visceral pain and in formalin- and capsaicin-induced neuro-inflammatory pain, in a naloxone-sensitive manner, suggesting the participation of endogenous opiates in its mechanism. In capsaicin test, the antinociceptive effect of mangiferin (30 mg/kg) was not modified by respective competitive and non-competitive transient receptor potential vanilloid 1 (TRPV1) antagonists, capsazepine and ruthenium red, or by pretreatment with L-NAME, a non-selective nitric oxide synthase inhibitor, or by ODQ, an inhibitor of soluble guanylyl cyclase. However, mangiferin effect was significantly reversed by glibenclamide, a blocker of K(ATP) channels and in animals pretreated with 8-phenyltheophylline, an adenosine receptor antagonist. Mangiferin failed to modify the thermal nociception in hot-plate and tail-flick test models, suggesting that its analgesic effect is only peripheral but not central. The orally administered mangiferin (10-100 mg/kg) was well tolerated and did not impair the ambulation or the motor coordination of mice in respective open-field and rota-rod tests, indicating that the observed antinociception was unrelated to sedation or motor abnormality. The findings of this study suggest that mangiferin has a peripheral antinociceptive action through mechanisms that involve endogenous opioids, K(ATP)-channels and adenosine receptors.

Mangiferin ameliorates 6-hydroxydopamine-induced cytotoxicity and oxidative stress in ketamine model of schizophrenia.

BACKGROUND: Accumulating evidence indicates that mangiferin (MGF), a natural xanthone, by virtue of its antioxidant and antiinflammatory properties is neuroprotective. Here we sought to verify the cytoprotective role of MGF on cultured rat primary mesencephalic cells exposed to 6-hydroxydopamine (6-OHDA) in vitro, and the MGFs anti-inflammatory potential in mouse model of ketamine-induced schizophrenia in vivo. METHODS: 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT)-assay was performed tomeasure cell viability inmesencephalic cell cultures exposed to neurotoxin (6-OHDA, 40 µM). Schizophrenia was induced in mice by ketamine (50 mg/kg, ip, twice a day, for 7 days). The treatment effects of MGF (50 mg/kg, po, for 7 days) were verified on locomotor behavioral changes in open-field test, and on the oxidant stress-related increase in lipid-peroxidation (malondialdehyde) and interleukin-6 (IL-6) levels in brain tissues. RESULTS: MGF (10-100 µM) produced no per se effect on cell viability as measured by MTT assay, but significantly prevented the 6-OHDA-induced cell death in a concentration-dependent manner. Acridine orange/ethidium bromide (AO/EtBr) staining confirmed the absence of 6-OHDA-induced morphological changes characteristic of apoptosis/necrosis. In open-field test, ketamine-induced impaired locomotor activity and behavioral changes such as grooming and stereotyped but not rearing were effectively ameliorated by MGF pretreatment. Also, ketamine-associated increase in brain tissue levels of IL-6 and MDA were significantly lowered in MGF-pretreated mice. CONCLUSION: Mangiferin has a neurocytoprotective role related, at least in part, to an antioxidant and anti-inflammatory mechanism, which could be explored for more effective therapies of schizophrenia and other neurodegenerative diseases.

Relaxant effect and possible mechanism of 17-nor-subincanadine E in rabbit corpora cavernosa.

Compounds with dual action on cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP) may be a treatment option for erectile dysfunction, as they not only promote penile erection but also prevent the upregulation of phosphodiesterase-5. In this study, we examined the possible relaxant effect and mechanism of 17-nor-subincanadine E (SEC, 0.2-200 µmol l⁻¹), a plant-derived alkaloid, in rabbit corpus cavernosum (RbCC) strips that had been precontracted by exposure to phenylephrine (10 µmol l⁻¹) or a high concentration of K(+) (60 mmol l⁻¹) in vitro. In addition to SEC's effect on cAMP and cGMP levels, electrical field stimulation (EFS) in phenylephrine-precontracted RbCC and calcium chloride (1-100 mmol l⁻¹) evoked responses in depolarized RbCC were analysed. SEC relaxed the phenylephrine-precontracted RbCCs in a concentration-dependent manner. Atropine, guanethidine and N-ω-nitro-l-arginine methyl ester (L-NAME) did not have any effect on the relaxation of RBCCs. When 1H-(1, 2, 4)oxadiazole[4,3-a] quinoxalin-1-one (ODQ) was added, it effectively blocked the relaxant response of SEC. Although SEC enhanced the maximal relaxation produced by sodium nitroprusside (SNP) and forskolin in phenylephrine-precontracted cavernosal smooth muscle, it caused a decrease in the maximal contractile response induced by calcium chloride in depolarized RbCCs. The relaxant effect of SEC was paralleled by an increase in the tissue levels of the cyclic nucleotides cAMP and cGMP. We conclude that SEC promotes the relaxation of RbCC, possibly favouring cAMP and cGMP accumulation and calcium blockade. This novel mechanism could be useful for patients who do not benefit from phosphodiesterase inhibitors and for those with endothelial and nitrergic dysfunction, such as patients with diabetes, hypertension and dyslipidaemias.

Anti-inflammatory effect of α,ß-amyrin, a triterpene from Protium heptaphyllum, on cerulein-induced acute pancreatitis in mice.

OBJECTIVE: To evaluate the anti-inflammatory effect of α,ß-amyrin, a pentacyclic triterpenoid from Protium heptaphyllum, on cerulein-induced acute pancreatitis in mice. METHODS: Acute pancreatitis was induced in Swiss mice by five intraperitoneal injections of cerulein (50 µg/kg), at 1 h intervals. Mice received α,ß-amyrin (10, 30 and 100 mg/kg), thalidomide (200 mg/kg), or vehicle (3% Tween 80) orally 1 h before and 12 h after the cerulein challenge. The severity of pancreatitis was evaluated 24 h after cerulein by assessing serum pro-inflammatory cytokines and amylase activity, pancreatic myeloperoxidase (MPO), and thiobarbituric acid-reactive substances (TBARS), as well as by histology. RESULTS: α,ß-Amyrin and thalidomide significantly attenuated the cerulein-induced increase in tumor necrosis factor (TNF)-α, interleukin-6, lipase, amylase, MPO, and TBARS. Moreover, α,ß-amyrin greatly suppressed the pancreatic edema, inflammatory cell infiltration, acinar cell necrosis, and expressions of TNFα and inducible nitric oxide synthase. CONCLUSIONS: α,ß-Amyrin ameliorates cerulein-induced acute pancreatitis by acting as an anti-inflammatory and antioxidant agent.

Protective effect of anacardic acids from cashew (Anacardium occidentale) on ethanol-induced gastric damage in mice.

Cashew nut-shell liquid and the contained anacardic acids (AAs) have been shown to possess antioxidant, lipoxygenase inhibitory, anti-Helicobacter pylori and antitumor properties. Despite these known effects, hitherto there were no published reports on their likely gastroprotective effects. The present study was designed to verify whether AAs afford gastroprotection against the ethanol-induced gastric damage and to examine the underlying mechanism(s). Gastric damage was induced by intragastric administration of 0.2mL of ethanol (96%). Mice in groups were pretreated orally with AAs (10, 30 and 100mg/kg), misoprostol (50 microg/kg), or vehicle (2% Tween 80 in saline, 10mL/kg), 45min before ethanol administration. They were sacrificed 30min later, the stomachs excised, and the mucosal lesion area (mm(2)) measured by planimetry. Gastroprotection was assessed in relation to inhibition of gastric lesion area. To study the gastroprotective mechanism(s), its relations to capsaicin-sensitive fibers, endogenous prostaglandins, nitric oxide and ATP-sensitive potassium channels were analysed. Treatments effects on ethanol-associated oxidative stress markers GSH, MDA, catalase, SOD, and total nitrate/nitrite levels as an index of NO were measured in gastric tissue. Besides, the effects of AAs on gastric secretory volume and total acidity were analysed in 4-h pylorus-ligated rat. AAs afforded a dose-related gastroprotection against the ethanol damage and further prevented the ethanol-induced changes in the levels of GSH, MDA, catalase, SOD and nitrate/nitrite. However, they failed to modify the gastric secretion or the total acidity. It was observed that the gastroprotection by AAs was greatly reduced in animals pretreated with capsazepine, indomethacin, l-NAME or glibenclamide. These results suggest that AAs afford gastroprotection principally through an antioxidant mechanism. Other complementary mechanisms include the activation of capsaicin-sensitive gastric afferents, stimulation of endogenous prostaglandins and nitric oxide, and opening of K(+)(ATP) channels. These combined effects are likely to be accompanied by an increase in gastric microcirculation.

Gastroprotective effect of lupeol on ethanol-induced gastric damage and the underlying mechanism.

The effect of lupeol, a natural pentacyclic triterpene on ethanol-induced gastric damage in mice was evaluated. The gastroprotection was assessed by determination of changes in mean gastric lesion area, quantification of mucosal non-protein sulfhydryls (NP-SH), and characterized using drugs that influence the endogenous prostaglandins, alpha(2)-adrenoceptors, nitric oxide, K(ATP)-channels, and intracellular calcium. Orally administered lupeol (3, 10, and 30 mg/kg) significantly and dose-dependently attenuated the ethanol-induced gastric damage by 39-69%, whereas the positive control N-acetylcysteine (NAC, 300 mg/kg, i.p.) afforded 32% protection. Both lupeol and NAC restored the NP-SH depleted by ethanol but the lupeol effect was only marginal. Lupeol gastroprotection was attenuated by indomethacin and L-NAME, the respective COX and NO-synthase inhibitors and was weakly sensitive to alpha(2)-adrenergic antagonist yohimbine and K(ATP)-channel blocker glibenclamide, but more profoundly to calcium blocker verapamil. These pharmacological effects of lupeol may synergistically contribute to alleviating the ethanol-associated gastric damage, which is multifactorial.

Dragon's blood from Croton urucurana (Baill.) attenuates visceral nociception in mice.

Dragon's blood, the red sap from Croton urucurana Baill. (Euphorbiaceae) has a profound history of traditional use in conditions such as inflammation, diarrhoea and gastrointestinal distress. Previous studies established its anti-inflammatory, antidiarrhoeal and analgesic properties and in this study we verified its potential to suppress visceral pain, using capsaicin- and cyclophosphamide-induced models of visceral nociception. Mice that received intra-colonic capsaicin (0.3%, 50 microl/animal) or intraperitoneal injection of cyclophosphamide (400 mg/kg) manifested spontaneous nociceptive behaviors or crises, which were significantly suppressed in animal groups treated with red sap (200 and 400 mg/kg, p.o.) or that received N-acetylcysteine (750 mg/kg, i.p.) or morphine (7.5 mg/kg, s.c.), as positive controls. In capsaicin model, the antinociception produced by 200 mg/kg red sap was found to be naloxone-sensitive (2 mg/kg, i.p.), suggesting an opioid mechanism. In tests of open-field and pentobarbital-sleeping time, mice received 200mg/kg red sap showed no significant alterations in either locomotion frequency or on sleeping time, indicating that the observed antinociception is not a consequence of sedation or motor abnormality. These findings highlight the visceral antinociceptive property of Croton urucurana sap and further support its ethno-medical use to alleviate pain associated with gastrointestinal and other related disorders.

12-Acetoxyhawtriwaic acid lactone, a diterpene from Egletes viscosa, attenuates capsaicin-induced ear edema and hindpaw nociception in mice: possible mechanisms.

The diterpene, 12-acetoxyhawtriwaic acid lactone (AHAL, tanabalin) isolated from the flower buds of Egletes viscosa Less. (Asteraceae) was evaluated on capsaicin-induced ear edema and hindpaw nociception in mice. AHAL (12.5, 25 and 50 mg/kg, P. O.) significantly attenuated the ear edema response to topically applied capsaicin (250 microg), in a dose-related manner. At similar doses, AHAL also suppressed the nocifensive paw-licking behavior induced by intraplantar injection of capsaicin (1.6 microg). These responses to capsaicin were also greatly inhibited by ruthenium red (3 mg/kg, S. C.), a non-competitive capsaicin receptor (TRPV1) antagonist. The anti-edema effect of AHAL (50 mg/kg) seems unrelated to either blockade of mast cell degranulation or to histamine and serotonin receptor antagonism since AHAL did not modify the paw edema response induced by intraplantar injections of compound 48/80, histamine or serotonin. However, the hindpaw edema induced by substance P and vascular permeability increase induced by intraperitoneal acetic acid were significantly suppressed by AHAL. The antinociceptive effect of AHAL (50 mg/kg) was unaffected by naloxone pretreatment but was significantly antagonized by theophylline and glibenclamide, the respective blockers of adenosine and K(ATP)-channels. AHAL (50 mg/kg, P. O.) did not impair the ambulation or motor coordination of mice in open-field and rota-rod tests. These data suggest that AHAL inhibits acute neurogenic inflammation possibly involving capsaicin-sensitive TRPV1-receptors, endogenous adenosine and ATP-sensitive potassium channels.

Protective effect of alpha- and beta-amyrin, a triterpene mixture from Protium heptaphyllum (Aubl.) March. trunk wood resin, against acetaminophen-induced liver injury in mice.

In the search of hepatoprotective agents from natural sources, alpha- and beta-amyrin, a triterpene mixture isolated from the trunk wood resin of folk medicinal plant, Protium heptaphyllum was tested against acetaminophen-induced liver injury in mice. Liver injury was analysed by quantifying the serum enzyme activities and by histopathological observations. In mice, acetaminophen (500 mg/kg, p.o.) caused fulminant liver damage characterized by centrilobular necrosis with inflammatory cell infiltration, an increase in serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities, a decrease in hepatic glutathione (GSH) and 50% mortality. Pretreatment with alpha- and beta-amyrin (50 and 100 mg/kg, i.p. at 48, 24, and 2 h before acetaminophen) attenuated the acetaminophen-induced acute increase in serum ALT and AST activities, replenished the depleted hepatic GSH, and considerably reduced the histopathological alterations in a manner similar to N-acetylcysteine, a sulfhydryls donor. Also, the acetaminophen-associated mortality was completely suppressed by terpenoid pretreatment. Further, alpha- and beta-amyrin could potentiate the pentobarbital (50 mg/kg, i.p.) sleeping time, suggesting the possible suppression of liver cytochrome-P450. These findings indicate the hepatoprotective potential of alpha- and beta-amyrin against toxic liver injury and suggest that the diminution in oxidative stress and toxic metabolite formation as likely mechanisms involved in its hepatoprotection. In conclusion, this study supports the traditional use of Protium heptaphyllum resin as a medicinal agent and suggests the feasibility of developing herbal drugs for treatment of liver disorders.

Anuloplastia concêntrica do anel mitral, isolada ou associada à ressecção quadrangular, em crianças e jovens / Mitral annuloplasty either in isolation or associated with posterior quadrantectomy in young patients

OBJETIVO: Descrever procedimento cirúrgico de anuloplastia concêntrica do anel mitral sem prótese, isolada ou associada à ressecção quadrangular com plicatura póstero-medial do anel mitral, e analisar os resultados imediatos e tardios obtidos. MÉTODO: Entre fevereiro de 1986 e fevereiro de 2001, realizamos 790 procedimentos abordando a valva mitral, 41 foram realizados em crianças e adolescentes menores de 20 anos (média de 9,7 anos). Vinte (48,7 por cento) pacientes eram do sexo feminino e 21 (51,3 por cento) do masculino. A doença reumática foi responsável pelas lesões em 92,6 por cento dos casos e a degeneração mixomatosa em apenas 7,4 por cento. No período pré-operatório, 22 (53,6 por cento) pacientes estavam em classe funcional III e 19 (46,4 por cento) em classe funcional IV, advindos de repetidos surtos de febre reumática, agravados pela desnutrição. A técnica cirúrgica utilizada foi a anuloplastia concêntrica, aplicada isoladamente ou em associação à ressecção quadrangular com plicatura póstero-medial. O curso do seguimento pós-operatório foi de 7 meses a 15 anos (3/2/1986 a 12/2/2001). RESULTADOS: A mortalidade hospitalar foi de 2,4 por cento. Os pacientes receberam alta sem sopro sistólico de regurgitação mitral. Dois pacientes apresentaram, ao longo dos anos (4 e 11 anos), estenose mitral e necessitaram reoperação, um deles operado com dois anos de idade. Dois doentes foram reoperados para corrigir disfunção aórtica previamente abordada por plastia (12 e 18 meses após a primeira operação), morrendo e contribuindo para mortalidade tardia de 5 por cento. CONCLUSAO: Consideramos a técnica empregada um procedimento alternativo, válido, de aplicação preferencial em crianças e adolescentes, de fácil reprodução e de baixíssimo custo.

Gastroprotective and anti-inflammatory effects of resin from Protium heptaphyllum in mice and rats.

The natural resin collected from the trunk wood of Protium heptaphyllum is used in folk medicine to treat inflammatory conditions and to hasten wound repair. In the search of new potential anti-inflammatory agents with gastroprotective property, the present study evaluated its effects in experimental models of gastric ulcer and inflammation. In mice, the resin (200 and 400 mg/kg) significantly attenuated the gastric damage induced by ethanol or acidified ethanol (HCl/ethanol), in a manner similar to N-acetyl-L-cysteine (NAC), a replenisher of sulfhydryls. Unlike NAC the resin failed to restore the ethanol-induced depletion of non-protein sulfhydryl content, indicating a different mechanism of gastroprotection. However, in 4-h pylorus-ligated rats, the resin significantly reduced the total acidity without much change in gastric secretory volume. In rats, at similar doses the resin did not modify the hind-paw edema induced by carrageenan, but effectively reduced the formation of cotton pellet-induced granuloma, suggesting its inhibitory effect on collagen formation but not on acute edema. Furthermore, the vascular permeability increase induced by acetic acid was significantly reduced in mice that received 400 mg/kg resin. The resin demonstrated no overt toxicity in mice up to an oral dose of 5 g/kg. Phytochemical analysis revealed the presence of alpha- and beta-amyrins as principal triterpenoid constituents of resin, which were previously described to have anti-ulcer property. These findings indicate the potential gastroprotective and anti-inflammatory property of P. heptaphyllum resin and further support its popular use in gastrointestinal disorders.