Ação cicatrizante de plantas medicinais: um estudo de revisão / Healing action of medicinal plants: a review

Plantas Medicinais são utilizadas desde a antiguidade para tratar uma série de doenças desempenhando um papel fundamental na saúde mundial. O uso da fitoterapia é muitas vezes o único recurso terapêutico de algumas comunidades. A Organização Mundial da Saúde reconhece a fitoterapia como uma alternativa de tratamento viável com baixo custo e recomenda o levantamento, identificação, estímulo e orientação do uso das plantas medicinais que possuem eficácia e segurança terapêutica comprovada. Nos últimos anos, os fitoterápicos ganharam espaço importante na reparação de tecidos, obtendo a partir deles formulações que agem no tratamento das feridas. O presente estudo teve por objetivo analisar pesquisas envolvendo plantas medicinais e seu poder cicatrizante. Foram utilizados dados de bases online, dos últimos dez anos, utilizando como descritores: "feridas, cicatrização, plantas medicinais". Foram analisados os nomes científico e popular das plantas, a parte da planta que foi utilizada para os experimentos, tipo de extração e utilização, classes das substâncias e efeito na cicatrização. As plantas pesquisadas foram: Aloe vera (L.) Burm. f. (Babosa), Coronopu didymus (Mastruz), Tabebuia avellanedae (Ipê roxo), Arnica Montana L. (Arnica), Orbignya phalerata (Babaçu), Stryphnodendron adstringens Martius (Barbatimão), Caesalpinia ferrea Martius (Jucá), Chenopodium ambrosioides L. (Erva de Santa Maria), Triticum vulgare (Trigo), Tabernaemontana catharinensis (Jasmim), Calendula officinalis (Calêndula) e Helianthus annus (Girassol), Catharanthus roseus L. (Vinca Rosea) e Schinus terebinthifolius Raddi (Aroeira). Assim, pode-se observar que todas as plantas estudadas no artigo favoreceram o processo de cicatrização por meio de diferentes atividades, e que essas atividades estão relacionadas com as diversas classes de metabólitos

Medicinal plants have been used to treat a number of diseases since ancient times, and play a key role in human health. In recent decades, modern medicine has made great advances, but plants still contribute to the development of medicines. The use of herbal medicine is often the only therapeutic resource available in some communities. The World Health Organization recognizes herbal therapy as a viable treatment alternative at a low cost and recommends the collection, identification, stimulation and guidance of the use of medicinal plants that have presented efficacy and safety therapeutics. In recent years, herb therapy has gained important space in the repair of tissues through formulations that act in the treatment of wounds. The aim of this study was to analyze studies involving medicinal plants and their healing potential. Data from online databases from the past ten years were analyzed, using the descriptors: "wounds, healing, medicinal plants". The scientific and popular names of plants, the part of the plant used, type of extraction, therapeutic use, classes of substances and effect on wound healing were analyzed. The plants studied were: Aloe vera (L.) Burm. f. (Babosa), Coronopu didymus (lesser swine cress), Tabebuia avellanedae (pink ipe), Arnica Montana L. (wolf's bane), Orbignya phalerata (Babassu), Stryphnodendron adstringens Martius (Barbatimão), Caesalpinia ferrea Martius (Brazilian ironwood), Chenopodium ambrosioides L. (wormseed), Triticum vulgare (wheat), Tabernaemontana catharinensis (Jasmin), Calendula officinalis (Calendula) and Helianthus annus (sunflower), Catharanthus roseus L. (Madagascar periwinkle) and, Schinus terebinthifolius Raddi (Brazilian peppertree). Thus, the results showed that all the studied plants favored the wound healing process through different mechanism. These activities may be related to the different classes of substances

Athletes with higher VO2max present reduced oxLDL after a marathon race.

BACKGROUND: During a session of prolonged and exhaustive exercise, such as a marathon race, large quantities of free radicals are produced and can oxidise (ox) several molecules, such as low-density lipoprotein (LDL). To prevent oxidative damage, athletes present higher antioxidant levels. However, the effect of marathon running on the natural IgM or IgG anti-oxLDL autoantibodies is not understood. Thus, we investigated the effect of a marathon race on oxidative stress and the mechanisms of control of this stress. METHODS: Blood samples of 20 marathon runners were collected 24 hours before, immediately and 72 hours after a marathon race to evaluate: plasma lipid profile; serum levels of oxLDL and anti-oxLDL autoantibodies (IgM and IgG isotype) and total antioxidant capacity (TAC). Maximum oxygen uptake (VO2max) was also determined. RESULTS: Immediately after the race, oxLDL and TAC levels decreased in comparison to the basal levels; however, the IgM or IgG anti-oxLDL levels remain unchanged. Whereas no differences were observed in the IgM or IgG anti-oxLDL levels 72h after the marathon, the oxLDL and TAC levels returned to the basal values. Significant positive correlations were observed between oxLDL and LDL-cholesterol before, and 72h after the marathon. Significant negative correlations were observed between oxLDL and VO2max immediately after the marathon and 72 h later, as well as between oxLDL and TAC 72 h after the race. CONCLUSIONS: Athletes with a higher VO2max and total antioxidant activity presented reduced LDL oxidation. The levels of IgM or IgG anti-oxLDL autoantibodies were not affected by running the marathon.

Atlantic salmon (Salmo salar L.) parr fed genetically modified soybeans and maize: Histological, digestive, metabolic, and immunological investigations.

Physiological and health related responses to dietary inclusion of genetically modified (GM) full-fat soybean meal (Roundup Ready; GM-soy) and maize (MON810 Bt-maize; GM-maize), as well as non-parental, untransformed lines (nGM-soy and nGM-maize D2), were evaluated in farmed Atlantic salmon (Salmo salar L.) parr during the first 8 months of feeding. Significant effects of dietary GM presence were only found in intestinal Na+-dependent d-glucose uptake and SGLT1 protein level in the region pyloric caeca in which the highest values were found in the GM-soy, intermediate in the nGM-soy, and lowest in the standard FM fed groups. Data from this study confirm that GM soybeans (RRS) and maize (MON810) at inclusion levels of about 6% appear to be as safe as commercially available nGM soy and maize in diets for Atlantic salmon parr. Results from studies with higher inclusion levels and with non-modified, isogenic or near-isogenic parental lines as control groups are pending.

Characterisation of intestinal peptide transporter of the Antarctic haemoglobinless teleost Chionodraco hamatus.

H(+)/peptide cotransport was studied in brush-border membrane vesicles (BBMV) from the intestine of the haemoglobinless Antarctic teleost Chionodraco hamatus by monitoring peptide-dependent intravesicular acidification with the pH-sensitive dye Acridine Orange. Diethylpyrocarbonate-inhibited intravesicular acidification was specifically achieved in the presence of extravesicular glycyl-L-proline (Gly-L-Pro) as well as of glycyl-L-alanine (Gly-L-Ala) and D-phenylalanyl-L-alanine (D-Phe-L-Ala). H(+)/Gly-L-Pro cotransport displayed saturable kinetics, involving a single carrier system with an apparent substrate affinity (K(m,app)) of 0.806+/-0.161 mmol l(-1). Using degenerated primers from eel and human (PepT1) transporter sequence, a reverse transcription-polymerase chain reaction (RT-PCR) signal was detected in C. hamatus intestine. RT-PCR paralleled kinetic analysis, confirming the hypothesis of the existence of a PepT1-type transport system in the brush-border membranes of icefish intestine. Functional expression of H(+)/peptide cotransport was successfully performed in Xenopus laevis oocytes after injection of poly(A)(+) RNA (mRNA) isolated from icefish intestinal mucosa. Injection of mRNA stimulated D-Phe-L-Ala uptake in a dose-dependent manner and an excess of glycyl-L-glutamine inhibited this transport. H(+)/peptide cotransport in the Antarctic teleost BBMV exhibited a marked difference in temperature optimum with respect to the temperate teleost Anguilla anguilla, the maximal activity rate occurring at approximately 0 degrees C for the former and 25 degrees C for the latter. Temperature dependence of icefish and eel intestinal mRNA-stimulated uptake in the heterologous system (oocytes) was comparable.

Characterisation of the H(+)/peptide cotransporter of eel intestinal brush-border membranes.

H(+)/peptide cotransport in brush-border membrane vesicles (BBMVs) from eel (Anguilla anguilla) intestine was studied by measuring d-[(3)H]-phenylalanyl-l-alanine uptake and by monitoring peptide-dependent intravesicular acidification using the pH-sensitive dye Acridine Orange. d-[(3)H]-phenylalanyl-l-alanine influx was greatly stimulated by an inside-negative membrane potential and enhanced by an inwardly directed H(+) gradient. In parallel, vesicular H(+) influx was significantly increased in the presence of extravesicular d-phenylalanyl-l-alanine or a series of glycyl and l-prolyl peptides. H(+)/peptide cotransport displayed saturable kinetics involving a single carrier system with apparent substrate affinities of 0.9-2.6 mmol l(-1) depending on the particular peptide. All substrates tested competed with this system. Pre-incubation of BBMVs with dipeptides prevented diethylpyrocarbonate inhibition of transport activity, suggesting that the substrates mask histidine residues involved in the catalytic function of the transporter. Using human PepT1-specific primers, a reverse transcription-polymerase chain reaction (RT-PCR) signal was detected in eel intestine. Our results suggest that, in eel intestine, a brush-border membrane 'low-affinity'-type H(+)/peptide cotransport system is present that shares kinetic features with the mammalian intestinal PepT1-type transporters.

Gadobenate dimeglumine and cerebral glucose metabolism. Continuous monitoring of striatal lactate levels in freely moving rats.

PURPOSE: Brain contrast-enhanced MR imaging reflects the leakage of contrast material into the brain tissue due to blood-brain barrier (BBB) disruption. The contact between brain tissue and contrast material requires a high level of neurotolerability of the contrast agent (CA). In the present study, we investigated the neurotolerability of the paramagnetic CA gadobenate dimeglumine, locally applied into the corpus striatum of freely moving rats, by evaluating its potential effects on cerebral glucose metabolism based on lactate levels. MATERIAL AND METHODS: Lactate levels were monitored using a microdialysis technique coupled with an enzyme reaction. A microdialysis probe for extracellular fluid sampling, together with a stainless steel cannula for CA administration, were inserted into the right corpus striatum of rats. Lactate levels were monitored for 2 h after gadobenate dimeglumine administration at 120 nmol/rat, at fixed volume of 1.2 microl. The same volume of artificial cerebrospinal fluid (aCSF) was administered to control rats. RESULTS: Gadobenate dimeglumine did not induce any significant changes in the lactate striatal levels over the 30-min period after administration. Small, but significant, reductions in lactate concentration were found from the 45-min control point after gadobenate dimeglumine administration. Lactate response showed the same pattern in rats given aCSF. CONCLUSION: Gadobenate dimeglumine, intracerebrally administered, did not affect cerebral glucose metabolism in rats as it showed the same behaviour as aCSF on cerebral glucose utilization. The gradual attenuation in the endogenous lactate release observed 45 min after test compound administration is possibly due to a slight reduction in the probe recovery. The present findings confirm the neurotolerability of gadobenate dimeglumine previously shown in behavioural and electrophysiological studies.

Neurotolerability of gadobenate dimeglumine. Evaluation of brain dopamine concentration in freely moving rats by microdialysis.

RATIONALE AND OBJECTIVES: Magnetic resonance imaging with contrast agents (CAs) is a procedure currently used for the diagnosis of neurologic pathologies. These pathologies are often characterized by blood-brain barrier disruptions, which determines a direct contact between CA and brain tissue. For this reason, an accurate assessment of neurotolerability is useful for the development of new CAs. The present study was designed to evaluate the neurotolerability of a new CA for MRI, gadobenate dimeglumine, employing a neurochemical method. The effect of gadobenate dimeglumine on the striatal levels of neurotransmitters was determined. In particular, the brain concentrations of dopamine and dopamine metabolites, 3,4-dihydroxyphenylacetic and homovanillic acid, were measured using microdialysis, after the direct application of gadobenate dimeglumine into the rat corpus striatum. Gadopentetate dimeglumine and gadoteridol were employed as reference compounds. METHODS: A microdialysis probe for brain extracellular fluid sampling and a stainless-steel cannula for CA application were chronically inserted into the right corpus striatum of rats. All CAs were administered at a dose of 5.4 nmol/rat. Dopamine and metabolite concentrations were analyzed using high-performance liquid chromatography. RESULTS: Gadobenate dimeglumine did not induce any significant changes in the extracellular levels of dopamine or dopamine metabolites up to 2 hours after administration. Gadoteridol produced similar results. Gadopentetate dimeglumine caused a moderate but not significant increase in dopamine levels throughout the duration of the experiments. CONCLUSIONS: Gadobenate dimeglumine directly administered into the corpus striatum of freely moving rats did not affect the dopaminergic system. This result demonstrates the safety of gadobenate dimeglumine under the experimental conditions used, thus confirming previous behavioral and electrophysiologic findings.

H(+)-glycyl-L-proline cotransport in brush-border membrane vesicles of eel (Anguilla anguilla) intestine.

A plasma membrane H(+)-glycyl-L-proline (Gly-L-Pro) cotransport mechanism has been identified in isolated eel intestinal brush-border membrane vesicles (BBMV) by both measuring radiolabeled Gly-L-Pro uptake and monitoring Gly-L-Pro-dependent H+ influx with the pH-sensitive dye acridine orange. The application of an inside negative membrane potential resulted in increasing Gly-L-Pro uptake, as well as the application of inwardly directed H+ gradient (although only when an inside negative membrane potential was present). Furthermore, vesicular H+ influx was found specifically associated with the presence of Gly-L-Pro in the extravesicular medium. The carrier-mediated nature of H(+)-Gly-L-Pro cotransport was assessed, and its concentration that yielded one-half maximal Gly-L-Pro influx was approximately 1.30 mM when measured by either radioactive or fluorescent tracers. Different dipeptides strongly inhibited Gly-L-Pro uptake by eel intestinal BBMV, as well as the cephalosporin antibiotic cephalexin, suggesting that dipeptide molecules and cephalosporin antibiotics may share a common transport system in eel intestinal BBMV.

Conditioned taste aversion in rats following intrathecal administration of contrast media.

PURPOSE: The occurrence of side-effects such as visceral malaise after intrathecal administration of the non-ionic radiography contrast media iomeprol, iopamidol, and iotrolan was assessed in rats by the conditioned tasted aversion procedure. METHODS: Reduced preference towards a saccharose solution compared with normal water following intraventricular administration of a contrast medium was used as a measure of the aversive response. RESULTS: At a dose of 100 mg I/kg none of the tested contrast media induced aversion. At 200 and 300 mg I/kg, both iopamidol and iomeprol induced significant aversive responses with respect to control, although the response of the iomeprol group appeared milder than that of the iopamidol group at a dose of 200 mg I/kg. Iotrolan could be tested only at the lowest dose since the high doses caused excessive mortality. CONCLUSION: Intrathecally administered iomeprol appeared to be well tolerated in rats at doses higher than those suggested for clinical use.

Clinical trial with muzolimine in healthy and hypertensive subjects: new vistas on the drug action.

The mechanism of muzolimine (3-amino-1-[3,4-dichloro-alpha-methyl-benzyl]-2 pyrazolin-5-one) action is still not completely defined. The identified site of action is the Henle loop, similarly to furosemide which acts also by mediating renal prostaglandin synthesis. The aim of the present study was to evaluate the early effects of muzolimine (30 mg per os) on renal function and prostaglandin urinary excretion in healthy controls and hypertensive subjects. Urinary flow reached the peak values by the third hour after the drug and a diuretic effect not directly dependent on glomerular filtration was observed, especially in hypertensive patients. In these cases the diuresis increased also due to a low glomerular filtration rate and tubular phenomena were more evident than in controls: an increasing Na+ tubular excretion and a parallel decreasing % Na+ reabsorption. Blood pressure was not significantly influenced by muzolimine in healthy subjects, while it returned to normal values in the hypertensive group. A cyclooxigenase inhibitor, lysine acetylsalicylate (1 g i.m.) administered 10 minutes after muzolimine, was not able to modify the parameters under consideration. Therefore a mediation by prostaglandins on the diuretic and antihypertensive effects of the drug under study may probably be excluded.

Free and bound testosterone in male heroin addicts.

The plasma levels of the active (free) fraction of testosterone (Te) and of Te Binding Globulin (TeBG) in a group of 42 heroin addicts with similar sexual difficulties were investigated for almost 2 years. Plasma levels of free Te were significantly low and TeBG were significantly high not only in the addicts with low total Te concentrations, but also in the addicts with normal values of total Te.