Virgínia Ramos Pizziolo

Antimicrobial and cytotoxic activities screening of some Brazilian medicinal plants used in Governador Valadares district

Os extratos etanolicos de plantas medicinais utilizadas por moradores da cidade de Governador Valadares foram avaliados quanto as atividades antimicrobiana e citotoxica. A pesquisa de campo foi realizada durante o periodo de 1997-2000, por meio de entrevistas com os raizeiros locais. Foram avaliados 33 extratos brutos de um total de 32 especies. Desses extratos, dez apresentaram toxicidade as larvas de Artemia salina (DL50<1000 ppm): Costus pisonis, Cymbopogon nardus, Eclipta alba, Eleutherine bulbosa, Erigium foetidium, Euphorbia tirucalli, Mikania hirsutissima, Momordica charantia, Solidago microglossa e Plectranthus ornatus. Quanto a atividade antimicrobiana, nenhum dos extratos apresentou atividade contra Escherichia coli. Entretanto, treze extratos mostraram-se ativos contra Staphylococcus aureus: E. alba, Scoparia sp., Arctium lappa, Chammomila tinctoria, E. bulbosa, M. hirsutissima, S. microglossa, Stachytarpheta dichotoma, Pffafia glomerata, Stenorrhyrchnus lanceolatum, Vernonia condensata e Lippia alba.

Naringin accelerates the regression of pre-neoplastic lesions and the colorectal structural reorganization in a murine model of chemical carcinogenesis

The aim of this study was to investigate the effect of Naringin on pre-neoplastic colorectal lesions induced by chemical carcinogen in rats. Female Wistar rats weighing 130.8±27.1 g received weekly one subcutaneous injection of 1,2-dimethylhydrazine (DMH, 20 mg/kg) for 10 weeks. The animals were divided into 5 groups with 6 animals in each group. Group 1: 0.9% saline; Group 2: DMH+0.9% saline; Group 3: DMH+Naringin (10 mg/kg); Group 4: DMH+Naringin (100 mg/kg); Group 5: DMH+Naringin (200 mg/kg). G2 and G3 showed a significant increase in ACF number, AgNOR/nucleus and mitosis compared to G1. G4 and G5 presented a significant reduction in these parameters compared to G2. The number of cells producing acidic and neutral mucins, red blood cells and the level of antioxidant minerals, such as copper, magnesium, selenium and zinc, were significantly reduced in G2 and G3, but similar in G4 and G5 compared to G1. Naringin, especially at 200 mg/kg, was effective in reducing the number of pre-neoplastic lesions in rats exposed to DMH. Some of these effects may be due to reduction in cellular proliferation and tissue levels of iron together with the recovery of antioxidant mineral levels induced by this flavonoid.

Plantas com possível atividade hipolipidêmica: uma revisão bibliográfica de livros editados no Brasil entre 1998 e 2008

The aim of this study was to survey medicinal plants indicated for the treatment of hyperlipidemia, hypercholesterolemia and/or atherosclerosis. This study was performed from a review of 32 books published in Brazil between 1998 and 2008, resulting in a list of 85 species belonging to 53 families, especially Asteraceae and Fabaceae, with 54 exotic and 31 native species. The species most often cited were Allium sativum (Alliaceae), Cynara scolymus (Asteraceae), Curcuma longa (Zingiberaceae), Allium cepa (Alliaceae), Echinodorus grandiflorus (Alismataceae), Taraxacum officinale (Asteraceae), Vernonia condensata (Asteraceae), Cuphea carthagenensis (Lythraceae) and Curcuma zedoaria (Zingiberaceae). Native species cited in at least 2 books were investigated for some scientific evidence related to possible hypolipidemic and hypocholesterolemic effects and/or action against atherosclerosis. Scientific studies related to these effects were found only for the native species Cuphea carthagenensis and Echinodorus grandiflorum, indicating the need for studies capable of assuring the safety and the efficacy as to the use of these species.

Effect of vitamin K in bone metabolism and vascular calcification: A review of mechanisms of action and evidences

ABSTRACT Osteoporosis is a public health concern associated with an increased risk of bone fractures and vascular calcification. Vitamin K presents unique benefits on these issues, although understudied. The two main forms of vitamin K are phylloquinone (vitamin K1) and menaquinone (vitamin K2). In this study, it was especially investigated the action of vitamin K2 in bones and vessels. Vitamin K2 has shown to stimulate bone formation by promoting osteoblast differentiation and carboxylation of osteocalcin, and increasing alkaline phosphatase, insulin-like growth factor-1, growth differentiation factor-15, and stanniocalcin 2 levels. Furthermore, vitamin K2 reduces the pro-apoptotic proteins Fas and Bax in osteoblasts, and decreases osteoclast differentiation by increasing osteoprotegerin and reducing the receptor activator of nuclear factor kappa-B ligand. In blood vessels, vitamin K2 reduces the formation of hydroxyapatite, through the carboxylation of matrix Gla protein and Gla rich protein, inhibits the apoptosis of vascular smooth muscle cells, by increasing growth arrest-specific gene 6, and reduces the transdifferentiation of vascular smooth muscle cells to osteoblasts. The commonly used dosage of vitamin K2 in human studies is 45 mg/day and its application can be an interesting strategy in benefitting bone and vascular health, especially to osteoporotic post-menopausal women.

Pharmacological activity of the hydroalcoholic extract from Hovenia dulcis thunberg fruit and the flavonoid dihydromyricetin during hypercholesterolemia induced in rats

No Brasil, o acidente vascular cerebral e a doenca arterial coronariana constituem as principais causas de mortalidade cardiovascular, sendo os altos niveis de colesterol LDL um dos principais fatores de risco. Nesse contexto, diversos extratos vegetais e substâncias naturais isoladas tem se mostrado promissoras como hipocolesterolemiantes. O objetivo do trabalho foi avaliar o potencial do extrato hidroalcoolico dos frutos de Hovenia dulcis e do flavonoide diidromiricetina na reducao do colesterol em ratos hipercolesterolemicos. Quarenta e dois ratos Wistar machos, foram distribuidos em 7 grupos de 6 animais, que receberam dieta suplementada com 1% de colesterol e 0,3% de acido colico, a excecao do grupo controle, que recebeu racao convencional. Posteriormente, os animais foram tratados com suspensoes orais contendo: atorvastatina 1,0 mg/kg; extrato de H. dulcis de 50,0 e 100,0 mg/kg; diidromiricetina de 25,0 e 50,0 mg/kg e veiculo (grupo controle). Avaliaram-se os parâmetros bioquimicos: colesterol total, HDL-C, LDL-C, triglicerides, AST, ALT e fosfatase alcalina. A dieta hipercolesterolemica foi efetiva na inducao da hipercolesterolemia, aumentando o colesterol total em 112,7% em relacao ao controle. Os tratamentos com as duas doses do extrato mostraram-se promissores como agentes hipocolesterolemiantes, ja que foram capazes de reduzir substancialmente o colesterol total e LDL-C, sem alterar significativamente triglicerides, as transaminases hepaticas e a fosfatase alcalina, incentivando, assim, a continuidade de estudos com a planta H. dulcis. Ja os grupos tratados com o flavonoide diidromiricetina, apesar de apresentarem reducao significativa do colesterol total e de LDL-C, apresentaram elevacoes nos triglicerides e nos parâmetros hepaticos, resultado indesejavel no âmbito das hipercolesterolemias.

Biometric, histomorphometric, and biochemical profile in atorvastatin calcium treatment of female rats with dexamethasone-induced osteoporosis

Objective To assess the effects of atorvastatin calcium in the treatment of dexamethasone-induced osteoporosis. Methods Osteoporosis induction consisted of the administration of an intramuscular dose of 7.5 mg/kg of body weight of dexamethasone, once a week for four weeks, except for the control animals (G1). The animals were divided into the following groups: G1 (control group without osteoporosis), G2 (control group with untreated osteoporosis), G3 (control group with osteoporosis treated with sodium alendronate 0.2 mg/kg) and G4 (group with osteoporosis treated with atorvastatin calcium 1.2 mg/kg). Serum alkaline phosphatase, bone alkaline phosphatase, and biometric and bone histomorphometric assessments were performed after 30 and 60 days of treatment onset. Results In relation to the biometric and histomorphometric analyses, at 60 days of treatment, G4 presented bone density (Seedor index), bone trabecular density, and cortical thickness of 0.222 ± 0.004 g/cm, 59.167 ± 2.401%, and 387,501 ± 8573 μm, respectively, with a positive and statistically significant difference (p < 0.05), in relation to G2. At 30 and 60 days of treatment, G4 presented statistically significant serum levels of alkaline phosphatase alkaline phosphatase (p < 0.05) that were higher than all groups (7.451 ± 0.173 μg/L and 7.473 ± 0.529 μg/L, respectively). Conclusion Treatment with atorvastatin calcium demonstrated the ability of this drug to increase osteoblastic activity and bone tissue repair activity, acting differently from alendronate sodium, which demonstrated predominantly antirebsorptive activity.

Antibiotic activity of Plectranthus ornatus Codd., a Traditional Medicinal Plant

The dichloromethane extract of Plectranthus ornatus Codd., a tradicional medicinal plant, showed antibiotic activity with minimum inhibitory concentration (MIC) values of 0.4 mg.mL-1 and 100 percent of biofilm inhibition against Staphylococcus aureus strains isolated from animals with mastitis infections. Based on these antibacterial activities, in addition to ethnopharmacological reports from healing men and farmers in Brazil, an herbal soap was produced from this active extract and was tested both in vitro and in vivo. In vivo assays conducted on these herbal soaps led to results similar to those previously conducted with the active extract. These results indicated the great potential of this plant for use as an excipient by preparing herbal antibacterial soaps as an alternative veterinary medicine aimed at controlling bovine mastitis infections on small Brazilian farms.

ANATOMICAL CHARACTERIZATION, CHEMICAL COMPOSITION AND CYTOTOXIC ACTIVITY OF TALINUM TRIANGULARE (JACQ.) WILLD (PORTULACACEAE)

This study aimed to assess chemical compositions and anatomy of Talinum triangulare extract and its cytotoxic activity in order to improve the knowledge of the specie. Leaves and stem fragments were fixed, sectioned and stained following the usual techniques in anatomy. The phytochemical screening was performed according to classical tests for secondary metabolites detection. Cytotoxicity was evaluated using as model the lethality of Artemia salina larvae. The studied leaf is amphistomatic and presents uniseriate epidermis covered by thin cuticle. The mesophyll is dorsiventral and the midrib consists of collateral vascular bundle. In the apical portion, the stem has vascular bundles delimiting the medular and cortical regions. A stratum of angular collenchyma is found beneath the epidermis. In the basal portion, the stem has about four layers of angular collenchyma and voluminous parenchyma cells internally delimiting the cortex. The phytochemical screening detects the presence of alkaloids, flavonoids, coumarins, terpenes and steroids. The mineral composition showed that the major element found was nitrogen, followed by potassium and magnesium, and the leaves are iron rich. The ethanolic extract did not show toxicity in the larvae of A. salina, with LD50> 1000 ppm, which proves the safe use of this specie in popular therapy.