Andréia Caroline Fernandes Salgueiro

The influence of Bauhinia forficata Link subsp. pruinosa tea on lipid peroxidation and non-protein SH groups in human erythrocytes exposed to high glucose concentrations

ETHNOPHARMACOLOGICAL RELEVANCE Bauhinia forficata (BF) has been traditionally used as tea in folk medicine of Brazil for treatment of Diabetes mellitus (DM). AIM OF THE STUDY To evaluate the effects of BF leaf tea on markers of oxidative damage and antioxidant levels in an experimental model of hyperglycemia in human erythrocytes in vitro. MATERIALS AND METHODS Human erythrocytes were incubated with high glucose concentrations or glucose and BF tea for 24h and 48h. After incubation lipid peroxidation and non-protein SH levels were analyzed. Moreover, quantification of polyphenols and flavonoids, iron chelating property, scavenging of DPPH, and prevention of lipid peroxidation in isolated lipids were also assessed. RESULTS A significant amount of polyphenols and flavonoids was observed. The main components found by LC-MS analysis were quercetin-3-O-(2-rhamnosyl) rutinoside, kaempferol-3-O-(2-rhamnosyl) rutinoside, quercetin-3-O-rutinoside and kaempferol-3-O-rutinoside. BF tea presents important antioxidant and chelating properties. Moreover, BF tea was effective to increase non-protein SH levels and reduce lipid peroxidation induced by high glucose concentrations in human erythrocytes. CONCLUSION The antioxidant effects of BF tea could be related to the presence of different phenolic and flavonoids components. We believe that these components can be responsible to protect human erythrocytes exposed to high glucose concentrations against oxidative damage.

Effects of Bauhinia forficata Tea on Oxidative Stress and Liver Damage in Diabetic Mice.

This study was designed to evaluate the effects of Bauhinia forficata Link subsp. pruinosa (BF) tea on oxidative stress and liver damage in streptozotocin (STZ)-induced diabetic mice. Diabetic male mice have remained 30 days without any treatment. BF treatment started on day 31 and continued for 21 days as a drinking-water substitute. We evaluated (1) BF chemical composition; (2) glucose levels; (3) liver/body weight ratio and liver transaminases; (4) reactive oxygen species (ROS), lipid peroxidation, and protein carbonylation in liver; (5) superoxide dismutase (SOD) and catalase (CAT) activities in liver; (6) δ-aminolevulinate dehydratase (δ-ALA-D) and nonprotein thiols (NPSH) in liver; (7) Nrf2, NQO-1, and HSP70 levels in liver and pancreas. Phytochemical analyses identified four phenols compounds. Diabetic mice present high levels of NQO-1 in pancreas, increased levels of ROS and lipid peroxidation in liver, and decrease in CAT activity. BF treatment normalized all these parameters. BF did not normalize hyperglycemia, liver/body weight ratio, aspartate aminotransferase, protein carbonyl, NPSH levels, and δ-ALA-D activity. The raised oxidative stress seems to be a potential mechanism involved in liver damage in hyperglycemic conditions. Our results indicated that BF protective effect could be attributed to its antioxidant capacity, more than a hypoglycemic potential.

Cryotherapy reduces skeletal muscle damage after ischemia/reperfusion in rats

The aim of this study was to analyze the effects of cryotherapy on the biochemical and morphological changes in ischemic and reperfused (I/R) gastrocnemius muscle of rats. Forty male Wistar rats were divided into control and I/R groups, and divided based on whether or not the rats were submitted to cryotherapy. Following the reperfusion period, biochemical and morphological analyses were performed. Following cryotherapy, a reduction in thiobarbituric acid‐reactive substances and dichlorofluorescein oxidation levels were observed in I/R muscle. Cryotherapy in I/R muscle also minimized effects such as decreased cellular viability, levels of non‐protein thiols and calcium ATPase activity as well as increased catalase activity. Cryotherapy also limited mitochondrial dysfunction and decreased the presence of neutrophils in I/R muscle, an effect that was corroborated by reduced myeloperoxidase activity in I/R muscle treated with cryotherapy. The effects of cryotherapy are associated with a reduction in the intensity of the inflammatory response and also with a decrease in mitochondrial dysfunction.

Sida tuberculata (Malvaceae): a study based on development of extractive system and in silico and in vitro properties

Sida tuberculata (Malvaceae) is a medicinal plant traditionally used in Brazil as an antimicrobial and anti-inflammatory agent. Here, we aimed to investigate the different extractive techniques on phytochemical parameters, as well as to evaluate the toxicity and antioxidant capacity of S. tuberculata extracts using in silico and in vitro models. Therefore, in order to determine the dry residue content and the main compound 20-hydroxyecdysone (20E) concentration, extracts from leaves and roots were prepared testing ethanol and water in different proportions. Extracts were then assessed by Artemia salina lethality test, and toxicity prediction of 20E was estimated. Antioxidant activity was performed by DPPH and ABTS radical scavenger assays, ferric reducing power assay, nitrogen derivative scavenger, deoxyribose degradation, and TBARS assays. HPLC evaluation detected 20E as main compound in leaves and roots. Percolation method showed the highest concentrations of 20E (0.134 and 0.096 mg/mL of extract for leaves and roots, respectively). All crude extracts presented low toxic potential on A. salina (LD50 >1000 µg/mL). The computational evaluation of 20E showed a low toxicity prediction. For in vitro antioxidant tests, hydroethanolic extracts of leaves were most effective compared to roots. In addition, hydroethanolic extracts presented a higher IC50 antioxidant than aqueous extracts. TBARS formation was prevented by leaves hydroethanolic extract from 0.015 and 0.03 mg/mL and for roots from 0.03 and 0.3 mg/mL on egg yolk and rat tissue, respectively (P<0.05). These findings suggest that S. tuberculata extracts are a considerable source of ecdysteroids and possesses a significant antioxidant property with low toxic potential.

Predictive antidiabetic activities of plants used by persons with Diabetes mellitus

BACKGROUND There are several ways to identify medicinal power of phytoconstituents, such as in silico evaluations. Furthermore, ethnopharmacological researches are important alternatives for the identification of plants with medicinal potential. Significantly, medicinal plants are widely used by persons with Diabetes mellitus (DM) to treat manifestations of this syndrome. OBJECTIVES i) to investigate the use of medicinal plants for individuals with DM and their health profile; ii) to evaluate in silico possible antidiabetic activities for main phytoconstituents of the commonly used plants. METHODS A questionnaire was used to measure consumption of medicinal plants. The Prediction of Activity Spectra for Substances (PASS) platform was employed to perform in silico evaluations. In silico predictions for antidiabetic activities were performed with the main compounds identified in a literature review which focused on the more utilized plants. RESULTS We interviewed 105 persons with DM, most them women (73.34%). Overall mean age was 59.35 years, and 97.14% of them were diagnosed with type 2 DM. An evaluation of the routine exams of the interviewees showed that they have a poor metabolic control. Among the interviewees, 67.62% confirmed the use medicinal plants. Main forms of consumed plant preparation were infusion of leaves and in association with mate (a typical beverage of southern Brazil). Most interviewees consume five or more cups of infusion per day, and when consumed with the mate, 1.73 liters per day. Forty-six medicinal plants were mentioned, and cows paw (Bauhinia) and jambolan (Syzygium cumini) were the most used. The main informed objective for the plant use was blood glucose control (69.01%). The PASS analysis presented six phytoconstituents with high antidiabetic prediction, especially, vicenin-2, the main phytochemical identified in Passiflora genus (Pa = 0.822). CONCLUSION Our data show that persons with DM use many plants as a complementary treatment to the traditional medicine. Moreover, part of these plants presented phytoconstituents with antidiabetic potential. These data can serve as a basis for future investigations, with the objective of exploring in vitro and in vivo antidiabetic effects of these plants and its compounds.