Phytochemical analysis and evaluation of antioxidant and antimycobacterial activity of Colletia paradoxa from Brazil

Colletia paradoxa (Spreng.) Esc. (Rhamnaceae, Colletieae) is a medicinal plant, threatened with extinction in Brazil, presenting great morphological variability. Our objective is to investigate the phytochemical components, antioxidant capacity and antimycobacterial activity of different morphotypes of C. paradoxa in different environments. For this, the crude extract of the leaves and branches of the individuals sampled was used. The elimination capacity of the free radicals was determined by the DPPH method, the antimycobacterial activity by the broth microdilution method and the phenolic content by the spectrophotometric method using the Folin-Ciocalteu reagent and by HPLC. The extracts of C. paradoxa and its morphotypes showed significant amounts of phenolic compounds, including quercetin, quercitrin and rutin, besides considerable antioxidant and antimycobacterial activity No connection was detected between the phytochemical composition and different morphotypes of C. paradoxa.

Hepatoprotective activity and phenolic profile of Zanthoxylum alatum Roxb. fruit extract

Zanthoxylum alatum Roxb. (Rutaceae) is a medicinal plant, which abundantly grows in the hilly areas of Pakistan. In the present study, the hepatoprotective activity of the Z. alatum whole fruit was evaluated. The hepatoprotective effect of the aqueous extracts was studied on mice liver damage using a single dose of paracetamol (640 mg/kg) orally by monitoring biochemical parameters. Pre-treatment of mice with Z. alatum (100 mg/kg) aqueous extract orally for four days prevented the paracetamol induced rise in serum transaminases (ALT and AST), restored the altered levels of antioxidant enzyme (catalase), thiobarbituric acid reactive substances (TBARS), non-protein thiol and ascorbic acid to near normal levels. The major phenolic acids, some flavonoid aglycone and glycosides were identified in fruit by high performance liquid chromatography. Ellagic acid (24.57±0.01mg/g), chlorogenic acid (10.65±0.01mg/g), gallic acid (9.15±0.02mg/g), chrysin (16.81±0.03), quercetin (16.81±0.03mg/g) and epicatechin (10.93±0.01) were prédominant in infusion of Z. alatum. The result substianted the hepatoprotective activity of Z. alatum which may be associated with its potential use in liver disease.

Tabernaemontana catharinensis ethyl acetate fraction presents antinociceptive activity without causing toxicological effects in mice

ETHNOPHARMACOLOGICAL RELEVANCE

Tabernaemontana catharinensis (Apocynaceae) is a medicinal plant used for the treatment of painful and inflammatory disorders. Here, we investigated the antinociceptive potential of the ethyl acetate fraction (Eta) from T. catharinensis leaves and assessed its toxic effects in mice to validate its popular use.

MATERIALS AND METHODS

Adult male Swiss mice (30-35g) were used. The Eta antinociceptive effect (200-800mg/kg, oral route (p.o.)) was evaluated in the acetic acid, formalin, capsaicin and tail-immersion tests. Adverse effects were analyzed using rotarod and open-field tests, body temperature, biochemical analysis and gastric lesions assessment. To evaluate the acute (OECD 423) or sub-acute (OECD 407) toxicity of the Eta, it was administered orally at a single (2000mg/kg) or repeated doses (100-400mg/kg/day for 28 days), respectively. Mortality, behavioral changes, biochemical and hematological parameters were evaluated. The Eta effect on cellular viability also was evaluated.

RESULTS

Eta (200-800mg/kg) inhibited the nociception caused by acetic acid (93.9±1.5%), formalin (86.2±10.8%) or capsaicin (75.4±3.3%) without inducing gastric lesions. Moreover, Eta neither altered the body temperature, biochemical parameters, nor forced or spontaneous locomotor activity of mice. The acute administration of the Eta (2000mg/kg) promoted a decrease in blood glucose levels and alanine aminotransferase activity. In the sub-acute toxicity study, Eta increased the aspartate aminotransferase activity (400mg/kg) and platelet distribution width (200mg/kg). Furthermore, Eta did not alter the cellular viability in cortical slices.

CONCLUSIONS

Eta presents antinociceptive effects and mild toxicity in mice. These results support its traditional use as a potential analgesic.

Antinociceptive and anti-inflammatory effect of the Scutia buxifolia Reissek stem barks extract

BACKGROUND

Scutia buxifolia (Rhamnaceae) has been extensively studied for its phenolics groups, which are able to capture free radicals; being therefore, considered promising as an antioxidant in preventing diseases resulting from oxidative stress.

HYPOTHESIS

Scutia buxifolia extract (SBE) presents antinociceptive and anti-inflammatory effect in mice.

STUDY DESIGN

SBE (400-800mg/kg) was tested in different pain models to investigate its antinociceptive and anti-inflammatory action.

METHODS

It was carried out the abdominal writhing test, capsaicin test, thermal hyperalgesia and incisional pain. The inflamed tissue by carrageenan was used for the analysis of interleukins (IL), interferon-γ (IFN-γ), tumor necrosis factor-α (TNF-α), c-reactive protein (CRP), nitrite and nitrate (NOx) determination and myeloperoxidase (MPO) activity. Furthermore, we evaluate the possible action mechanism of SBE using naloxone in capsaicin test.

RESULTS

SBE prevented the nociception caused by acetic acid, formalin and capsaicin test. However, neither the SBE prevented the thermal hyperalgesia in hot-plate test, nor the naloxone reversed the SBE antinociceptive effect in capsaicin test. Furthermore, the administration of SBE prevented significantly the increase of MPO activity, the NOx content, and the levels of IL-1, IL-6, TNF-α, INF-γ and CRP and was able to increase the IL-10 levels after the inflammation induced by carrageenan in mice. In addition, SBE prevented mechanical hyperalgesia in a postoperative pain model.

CONCLUSION

The SBE presents great antinociceptive and anti-inflammatory activity in mice but this effect not seem to have its action mechanism like opioids. It is possible that its antinociceptive effects are associated with levels decrease of inflammatory mediators.

Effect of Ginger and Turmeric Rhizomes on Inflammatory Cytokines Levels and Enzyme Activities of Cholinergic and Purinergic Systems in Hypertensive Rats

Inflammation exerts a crucial pathogenic role in the development of hypertension. Hence, the aim of the present study was to investigate the effects of ginger (Zingiber officinale) and turmeric (Curcuma longa) on enzyme activities of purinergic and cholinergic systems as well as inflammatory cytokine levels in Nω-nitro-L-arginine methyl ester hydrochloride-induced hypertensive rats. The rats were divided into seven groups (n = 10); groups 1-3 included normotensive control rats, hypertensive (Nω-nitro-L-arginine methyl ester hydrochloride) rats, and hypertensive control rats treated with atenolol (an antihypertensive drug), while groups 4 and 5 included normotensive and hypertensive (Nω-nitro-L-arginine methyl ester hydrochloride) rats treated with 4 % supplementation of turmeric, respectively, and groups 6 and 7 included normotensive and hypertensive rats treated with 4 % supplementation of ginger, respectively. The animals were induced with hypertension by oral administration of Nω-nitro-L-arginine methyl ester hydrochloride, 40 mg/kg body weight. The results revealed a significant increase in ATP and ADP hydrolysis, adenosine deaminase, and acetylcholinesterase activities in lymphocytes from Nω-nitro-L-arginine methyl ester hydrochloride hypertensive rats when compared with the control rats. In addition, an increase in serum butyrylcholinesterase activity and proinflammatory cytokines (interleukin-1 and - 6, interferon-γ, and tumor necrosis factor-α) with a concomitant decrease in anti-inflammatory cytokines (interleukin-10) was observed in Nω-nitro-L-arginine methyl ester hydrochloride hypertensive rats. However, dietary supplementation of both rhizomes was efficient in preventing these alterations in hypertensive rats by decreasing ATP hydrolysis, acetylcholinesterase, and butyrylcholinesterase activities and proinflammatory cytokines in hypertensive rats. Thus, these activities could suggest a possible insight about the protective mechanisms of the rhizomes against hypertension-related inflammation.

Phenolic composition and antiparasitic activity of plants from the Brazilian Northeast "Cerrado"

This work describes the antiparasitic and cytotoxic activities of three plant species from the Cerrado biome, Northeastern Brazil. Significant antiparasitic inhibition was observed against Trypanosoma cruzi (63.86%), Leishmania brasiliensis (92.20%) and Leishmania infantum (95.23%) when using ethanol extract from leaves of Guazuma ulmifolia Lam. (Malvaceae), at a concentration of 500 μg/mL. However, low levels of inhibition were observed when assessing leishmanicidal and trypanocidal (Clone CL-B5) activities of crude ethanol extracts from leaves and bast tissue of Luehea paniculata (Malvaceae) and leaves and bark of Prockia crucis (Salicaceae) at a concentration of 500 μg/mL. The extracts revealed the presence of phenolic acids such as gallic acid, chlorogenic acid, caffeic acid and rosmarinic acid, as well as flavonoids such as rutin, luteolin, apigenin and quercetin - the latter detected only in G. ulmifolia. G. ulmifolia extract displayed higher leishmanicidal activity probably due to the presence of quercetin, a potent known leishmanicidal compound. A cytotoxicity test indicated values over 50% at the highest concentration (1000 μg/mL) for all natural products, which were considered cytotoxic. This points out the need for further tests to enable future in vivo trials, including antineoplastic activity on human tumor cells.

Inhibition of metalloproteinase and proteasome activities in colon cancer cells by citrus peel extracts

BACKGROUND

Citrus peels are consumed in the form of infusions, candy or wine, based on their well-documented nutritional and medicinal properties. This study sought to investigate the effect of some citrus peels' [grapefruit (Citrus paradisii), orange (Citrus sinensis) and shaddock (Citrus maxima)] extracts on matrix metalloproteinase (MMP) and proteasome activities in primary human colonic tumor (Caco-2) and the metastatic cell lines (LoVo and LoVo/ADR) in a bid to explain the possible mechanism by which the peels could manage/prevent colon cancer.

METHODS

The inhibition of MMP and proteasome activities in the cells by the peel extracts, as well as the identification of phenolic compounds using high-performance liquid chromatography with diode-array detection (HPLC-DAD), was determined.

RESULTS

Orange peel extracts had the strongest inhibition of MMP in Caco-2 and LoVo cells, while shaddock had the least. Shaddock peel extracts also had the least MMP inhibition in LoVo/ADR lysates. Grapefruit had the least proteasome inhibition in Caco-2 and LoVo lysates, while there was no significant (p>0.05) difference in the proteasome inhibition of the peel extracts in LoVo/ADR lysates. The extracts inhibited proteasome activity in extract-treated cells, and HPLC fingerprinting of the extracts revealed the presence of some phenolic compounds such as quercetin, caffeic acid, kaempferol, catechin and naringin.

CONCLUSIONS

The inhibition of MMP and proteasome activities in colon cancer cell lines suggests the potential use of citrus peels as functional food in the management and/or prevention of colon cancer.

Effect of Two Ginger Varieties on Arginase Activity in Hypercholesterolemic Rats

Recently, ginger has been used in traditional Chinese medicine as an herbal therapy for treating several cardiovascular diseases, however, information on its mechanism of action is limited. The present study assessed the effect of two ginger varieties (Zingiber officinale and Curcuma longa) on the arginase activity, atherogenic index, levels of liver thiobarbituric acid reactive substances (TBARSs), and plasma lipids in rats fed with a high-cholesterol (2%) diet for 14 days. Following the treatment period, it was found that feeding a high-cholesterol diet to rats caused significant (p < 0.05) increases in arginase activity, atherogenic index, levels of TBARS, total cholesterol (TC), triglycerides (TGs), and low-density lipoprotein cholesterol (LDL-C) with a concomitant decrease in high-density lipoprotein cholesterol (HDL-C). However, both ginger and turmeric (2% and 4%) caused significant (p < 0.05) decreases in arginase activity and the atherogenic index, and prevented hypercholesterolemia by decreasing the TC, TGs, and LDL-C while increasing the HDL-C when compared with the controls. In conclusion, dietary supplementation with both types of rhizomes (ginger and turmeric) inhibited arginase activity and prevented hypercholesterolemia in rats that received a high-cholesterol diet. Therefore, these activities of ginger and turmeric represent possible mechanisms underlying its use in herbal medicine to treat several cardiovascular diseases.

Guava leaves polyphenolics-rich extract inhibits vital enzymes implicated in gout and hypertension in vitro

BACKGROUND/AIM

Elevated uric acid level, an index of gout resulting from the over-activity of xanthine oxidase (XO), increases the risk of developing hypertension. However, research has shown that plant-derived inhibitors of XO and angiotensin 1-converting enzyme (ACE), two enzymes implicated in gout and hypertension, respectively, can prevent or ameliorate both diseases, without noticeable side effects. Hence, this study characterized the polyphenolics composition of guava leaves extract and evaluated its inhibitory effect on XO and ACE in vitro.

MATERIALS AND METHODS

The polyphenolics (flavonoids and phenolic acids) were characterized using high-performance liquid chromatography (HPLC) coupled with diode array detection (DAD). The XO, ACE, and Fe(2+)-induced lipid peroxidation inhibitory activities, and free radicals (2,2-diphenylpicrylhydrazyl [DPPH]* and 2,2´-azino-bis-3-ethylbenzthiazoline-6-sulphonic [ABTS]*(+)) scavenging activities of the extract were determined using spectrophotometric methods.

RESULTS

Flavonoids were present in the extract in the order of quercetin > kaempferol > catechin > quercitrin > rutin > luteolin > epicatechin; while phenolic acids were in the order of caffeic acid > chlorogenic acid > gallic acids. The extract effectively inhibited XO, ACE and Fe(2+)-induced lipid peroxidation in a dose-dependent manner; having half-maximal inhibitory concentrations (IC50) of 38.24 ± 2.32 μg/mL, 21.06 ± 2.04 μg/mL and 27.52 ± 1.72 μg/mL against XO, ACE and Fe(2+)-induced lipid peroxidation, respectively. The extract also strongly scavenged DPPH* and ABTS*(+).

CONCLUSION

Guava leaves extract could serve as functional food for managing gout and hypertension and attenuating the oxidative stress associated with both diseases.

Safety assessment and behavioral effects of Solanum guaraniticum leaf extract in rats

ABSTRACT Solanum guaraniticum is a medicinal plant traditionally used to treat gastric and liver diseases. However, there is no documented evidence corroborating its safety. The present study evaluated the potential toxicity of S. guaraniticum leaf extract after acute administration in rats. Single doses of the extract (1.250, 2.500, and 5.000 mg/kg) were administered by gavage, and the rats were then monitored for 48 h and/or 14 days. Mortality, acute signs of toxicity, and general activity in the open field test were assessed as well as hematological and biochemical parameters, enzymatic activity (δ-aminolevulinate dehydratase and acetylcholinesterase), and oxidative stress parameters (lipid peroxidation level, non-protein thiol content, tissue catalase activity, and serum ferrous reducing power). Phytochemical analysis was also performed by HPLC. The results showed that extract administration produced no deaths (LD50 > 5,000 mg/kg), and no significant adverse effects regarding food consumption, body weight gain, gross pathology, or other parameters. However, the open field tests showed a decrease in spontaneous activity (crossing and rearing) mainly at 48 h after treatment. The results suggest that S. guaraniticum extract is not acutely toxic, but causes alterations in central nervous system activity.

Genotoxic and chromatographic analyses of aqueous extracts of Peltodon longipes Kunth ex Benth. (hortelã-do-campo)

Peltodon longipes is used as a stimulant and emmenagogue. The objective of this study was to perform genotoxic and chromatographic analyses of the extracts of two samples of P. longipes, collected from the cities of Santa Maria and Tupanciretã, RS, Brazil. The Allium cepa assay was used to analyze genotoxicity while high-performance liquid chromatography was employed to determine phenolic compounds. The genotoxicity experiment consisted of nine groups each comprising four A. cepa bulbs. Bulb roots were developed in distilled water and then transferred for the treatments, for 24 hours, and the negative control remained in water. The treatments were: aqueous extracts at concentrations of 5 and 15 g L-1 for each sample, plus four groups treated with 1% glyphosate, one of which was used as a positive control and the other three for testing DNA damage recovery using water and the extracts of P. longipes from Santa Maria. All extracts of P. longipes exhibited anti-proliferative potential, although the effect was significantly greater for the extracts from the Tupanciretã sample. This sample also contained the highest amount of rosmarinic acid and kaempferol, which may confer the effects found in these extracts. Only extracts from the Santa Maria sample exhibited genotoxic potential.

Centella asiatica and Its Fractions Reduces Lipid Peroxidation Induced by Quinolinic Acid and Sodium Nitroprusside in Rat Brain Regions

Oxidative stress has been implicated in several pathologies including neurological disorders. Centella asiatica is a popular medicinal plant which has long been used to treat neurological disturbances in Ayurvedic medicine. In the present study, we quantified of compounds by high performance liquid chromatography (HPLC) and examined the phenolic content of infusion, ethyl acetate, n-butanolic and dichloromethane fractions. Furthermore, we analyzed the ability of the extracts from C. asiatica to scavenge the 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) radical as well as total antioxidant activity through the reduction of molybdenum (VI) (Mo(6+)) to molybdenum (V) (Mo(5+)). Finally, we examined the antioxidant effect of extracts against oxidant agents, quinolinic acid (QA) and sodium nitroprusside (SNP), on homogenates of different brain regions (cerebral cortex, striatum and hippocampus). The HPLC analysis revealed that flavonoids, triterpene glycoside, tannins, phenolic acids were present in the extracts of C. asiatica and also the phenolic content assay demonstrated that ethyl acetate fraction is rich in these compounds. Besides, the ethyl acetate fraction presented the highest antioxidant effect by decreasing the lipid peroxidation in brain regions induced by QA. On the other hand, when the pro-oxidant agent was SNP, the potency of infusion, ethyl acetate and dichloromethane fractions was equivalent. Ethyl acetate fraction from C. asiatica also protected against thiol oxidation induced by SNP and QA. Thus, the therapeutic potential of C. asiatica in neurological diseases could be associated to its antioxidant activity.

In vitro antimicrobial and modulatory activity of the natural products silymarin and silibinin

Silymarin is a standardized extract from the dried seeds of the milk thistle (Silybum marianum L. Gaertn.) clinically used as an antihepatotoxic agent. The aim of this study was to investigate the antibacterial and antifungal activity of silymarin and its major constituent (silibinin) against different microbial strains and their modulatory effect on drugs utilized in clinical practice. Silymarin demonstrated antimicrobial activity of little significance against the bacterial strains tested, with MIC (minimum inhibitory concentration) values of 512 µg/mL. Meanwhile, silibinin showed significant activity against Escherichia coli with a MIC of 64 µg/mL. The results for the antifungal activity of silymarin and silibinin demonstrated a MIC of 1024 µg/mL for all strains. Silymarin and silibinin appear to have promising potential, showing synergistic properties when combined with antibacterial drugs, which should prompt further studies along this line.

Chromatographic analysis and antiproliferative potential of aqueous extracts of Punica granatum fruit peels using the Allium cepa test

Punica granatum L., locally known as romanzeira, is native to Asia but found throughout Brazil. P. granatum is used for treating inflammatory, infectious and respiratory diseases. The aim of this study was to evaluate the chromatography and genotoxicity of an aqueous extract of P. granatum (pomegranate) fruit peel using the Allium cepa L. test. The experiment set-up entailed 7 treatments: T1-distilled water, T2-tea 5 g.L-1, T3-tea 10 g.L-1, T4-glyphosate at 9.6%, T5-glyphosate with subsequent recovery in distilled water, T6-glyphosate with subsequent recovery in tea 5 g.L-1 and T7-glyphosate with subsequent recovery in tea 10 g.L-1. The rootlets were collected and fixed in ethanol:acetic acid (3:1) for 24 hours, then stored in 70% ethanol under refrigeration. Analysis was performed using high performance liquid chromatography for the quantification of the extracted phenolic compounds. Gallic acid, catechin, caffeic acid, and rutin were abundant in the extracts of P. granatum. The extracts were found to exhibit antiproliferative potential but not antimutagenic or genotoxic activity.

In vitro repellent effect of tea tree (Melaleuca alternifolia) and andiroba (Carapa guianensis) oils on Haemotobia irritans and Chrysomya megacephala flies

This study aimed to evaluate the repellent effect of tea tree (Melaleuca alternifolia) and andiroba (Carapa guianensis) essential oils on two species of flies (Haemotobia irritans and Chrysomya megacephala). For the in vitro studies, free-living adult flies were captured and reared in the laboratory. To verify the repellency effect, an apparatus was constructed where H. irritans and C. megacephala were exposed to andiroba and tea tree oils (5.0%), as well as to a known repellent (citronella, 5.0%) to validate the test. The study demonstrated that all three oils used showed in vitro repellent effect against both species of flies. It is possible to conclude that the essential oils (tea tree and andiroba) have repellent effect on these species of flies used in this study.

Physical chemistry evaluation of stability, spreadability, in vitro antioxidant, and photo-protective capacities of topical formulations containing Calendula officinalis L. leaf extract

Calendula is used widely in cosmetic formulations that present phenolic compounds in their chemical constitution. The objective of our research was to develop and evaluate the stability of topical formulations containing 5% hydro-ethanolic extract of calendula leaves, including spreadability, and in vitro photo-protective, and antioxidant capacity. To evaluate the stability, we used organoleptic characteristics, pH, and viscosity parameters. Antioxidant capacity was measured by the DPPH (2,2-diphenyl-1-picrylhydrazyl) method, and the photo-protective capacity by SPF spectrophotometric measure. All formulations were stable. The calendula extract formulations in gel and cream showed no significant variations in pH, and the cream formulations presented lower viscosity variations than gel formulations. The spreadability of the gel formulations was superior to those in cream. The formulations also presented good antioxidant capacities and an FPS of around 1.75. In accordance with the results, the formulations can be used as antioxidants, but considering the low SPF obtained, calendula cannot be considered as a stand-alone sunscreen, yet may well be tested in future studies towards verifying enhancement of synthetic sunscreens.

Eugenia uniflora leaves essential oil induces toxicity in Drosophila melanogaster: involvement of oxidative stress mechanisms

Eugenia unifloraL. (Myrtaceae family), also known as “pitanga”, is a tree species widely used in popular medicine.

Euphorbia tirucalli aqueous extract induces cytotoxicity, genotoxicity and changes in antioxidant gene expression in human leukocytes

The medicinal use of Euphorbia tirucalli has to be made with caution, as our study indicates that the aqueous extract induces genotoxicity and cytotoxicity in human leukocytes

Phenolic compounds from sandpaper (ficus exasperata) leaf inhibits angiotensin 1 converting enzyme in high cholesterol diet fed rats

ETHNOPHARMACOLOGICAL RELEVANCE

Sandpaper [Ficus exasperata Vahl (Moraceae)] leaf has been reportedly used in folklore for the management/treatment of cardiovascular diseases with little/or no scientific basis for their action. This study sought to investigate the effect of dietary supplementation of sandpaper leaf on angiotensin-I converting enzyme (ACE) activity in hypercholesterolemia as well as the effect of their phenolic extract on this enzyme in vitro.

MATERIALS AND METHODS

The phenolic extract was prepared, then, the inhibitory effect of the leaf extract on ACE was determined in vitro. Thereafter, the effect of dietary supplementation of sandpaper leaf on angiotensin-I converting enzyme (ACE) activity in high cholesterol diet fed rats for 14 days was evaluated as well as some biochemical parameters.

RESULTS

The result revealed that under in vitro condition, the phenolic extract inhibited ACE (IC50=14.7µg/mL) in a dose-dependent manner (0-10µg/mL). Feeding high cholesterol diets to rats caused a significant (P<0.05) increase in the ACE activity. However, there was a significant (P<0.05) decrease in the ACE activity as a result of supplementation with the sand paper leaves. Furthermore, there was a significant (P<0.05) increase in the plasma lipid profile with a concomitant increase in malondialdehyde (MDA) content in rat liver and heart tissues. However, supplementing the diet with sandpaper leaf (either 10% or 20%) caused a significant (P<0.05) decrease in the plasma total cholesterol (TC), triglyceride (TG), very low density lipoprotein-cholesterol (VLDL-C), and low-density lipoprotein-cholesterol levels (LDL-C), and in MDA content in the tissues. Conversely, supplementation caused a significant (P<0.05) increase in plasma high-density lipoprotein-cholesterol level when compared with the control diet. Reversed phase HPLC analysis of the extract revealed Quercitrin (43.7mg/g), chlorogenic acid (42.8mg/g) and caffeic acid (33.9mg/g) as the major phenolics in the leaf.

CONCLUSION

The inhibition of ACE activity and prevention of hypercholesterolemia by sandpaper leaf could be part of the possible mechanism underlying its anti-hypertensive property which could lay credence to its use in folk medicine. However, these activities may be directly/indirectly attributed to the polyphenolics present.

Antiulcerogenic activity of Scutia buxifolia on gastric ulcers induced by ethanol in rats

Gastric ulcers affect many people around the world and their development is a result of the imbalance between aggressive and protective factors in the gastric mucosa. Scutia buxifolia, commonly known as coronilha, has attracted the interest of the scientific community due to its pharmacological properties and its potential therapeutic applications. In this study, the preventive effects of the crude extract of Scutia buxifolia (ceSb) against gastric ulcer induced by 70% ethanol were evaluated in male Wistar rats. In addition, the composition of ceSb was clarified by high-performance liquid chromatography (HPLC). S. buxifolia extract (100, 200 and 400 mg/kg body weight) attenuated oxidative and histopathological features induced by ethanol. Moreover, all evaluated doses of ceSb caused significant (P<0.001 and P<0.0001) and dose-dependent increase in sulfhydryl groups (NPSH) levels, catalase (CAT) and superoxide dismutase (SOD) activities. Furthermore, the administration of ceSb reversed the increase in lipid peroxidation produced by ethanol. The protective effect of the extract could be attributed to antioxidant compounds present in the ceSb, such as flavonoids and phenolic acids, which were quantified by HPLC. Thus, an antioxidant effect of the extract leads to a protection on gastric tissue. These results indicate that S. buxifolia could have a beneficial role against ethanol toxicity by preventing oxidative stress and gastric tissue injury.

In vitro trypanocidal activity of macela (Achyrocline satureioides) extracts against Trypanosoma evansi

The aim of this study was to verify the trypanocidal effectiveness of aqueous, methanolic, and ethanolic extracts of Achyrocline satureioides against Trypanosoma evansi in vitro. A. satureioides extracts, known as macela, were used on trypomastigotes at different concentrations (1, 5, 10, 50, 100, 500, and 1,000 µg/ml) and exposure times (0, 1, 3, 6, and 9 hr). A dose-dependent effect was observed when the 3 extracts were tested. The concentrations of 1, 5, and 10 µg/ml were not able to kill trypomastigotes until 3 hr after exposure, and the highest concentrations (500 and 1,000 µg/ml) were able to kill all trypomastigotes after 1 hr. When the time of exposure was increased up to 9 hr, the concentrations at 50 and 100 µg/ml were 100% effective to 3 extracts. The chemical analysis of the extracts revealed the presence of flavonoids, a trypanocidal compound already described. Based on the results, we can conclude that the A. satureioides extracts exhibit trypanocidal effects.

Protective effects of Croton campestris A. St-Hill in different ulcer models in rodents: evidence for the involvement of nitric oxide and prostaglandins

ETHNOPHARMACOLOGICAL RELEVANCE

Croton campestris A. St.-Hill., popularly known as "velame do campo", is a species native from savannah area of Northeast Brazil, which is used by traditional communities in folk medicine for a variety of health problems, especially detoxification, inflammation and gastritis. The present study investigates the possible gastric antiulcer activity of Croton campestris root extract (CCRE) and mechanisms of action underlying this effect.

MATERIALS AND METHODS

Gastric lesions were induced in mice by ethanol, acidified ethanol and indomethacin. CCRE was previously administered orally in doses ranging from 50 to 750 mg/kg. Stomach lesions were measured. The involvement of Nitric Oxide (NO), prostaglandins (PGEs), ATP-dependent K+ channel and adrenergic receptor was investigated through specific inhibitors.

RESULTS

CCRE produced significant antiulcer activity against absolute ethanol, acidified ethanol and indomethacin induced gastric lesions. The pretreatment with L-NAME (10 mg/kg, p.o.), an inhibitor of nitric oxide synthesis and indomethacin (10 mg/kg, s.c.), an inhibitor of prostaglandin production, reversed the antiulcer action of CCRE.

CONCLUSION

Taking together, these results suggest that the antiulcer activity of CCRE is dependent of NO and prostaglandin pathways possibly due to its ability to stimulate the synthesis of NO, and activation of endogenous prostaglandin production. Therefore, the use of CCRE in traditional Brazilian medicine against gastric disorders has a scientific basis.

Co-encapsulation of resveratrol and curcumin in lipid-core nanocapsules improves their in vitro antioxidant effects

Resveratrol and curcumin are natural antioxidants found in the human diet that have been used in the prevention and treatment of different diseases associated with oxidative stress. Aiming to improve the antioxidant effects of resveratrol and curcumin, lipid-core nanocapsules containing the combination of both polyphenols were developed. Physicochemical characteristics were evaluated and compared to the formulations containing each polyphenol individually. Co-encapsulation did not influence nanotechnological characteristics, and all formulations presented mean diameter around 200 nm, low polydispersity index, and encapsulation efficiency close to 100%. Nanoencapsulation increases the photostability of resveratrol and curcumin, and co-encapsulation improves resveratrol photostability. The in vitro antioxidant activity of polyphenols against HO radicals was enhanced by nanoencapsulation, and a better effect was observed after their co-nanoencapsulation. Also, nanocapsules exhibited controlled release profile, for both polyphenols. The results showed that the strategy to co-encapsulate resveratrol and curcumin is a promising approach to improve the performance of medicines used to prevent and treat diseases associated with oxidative stress.

Antiinflammatory effects of Viola tricolor gel in a model of sunburn in rats and the gel stability study

ETHNOPHARMACOLOGICAL RELEVANCE

Viola tricolor, popularly known as heartsease has been empirically used in several skin disorders, including burns.

AIM OF THE STUDY

The objective of this study was investigate the antinociceptive and antiinflammatory effect of a gel containing extract of Viola tricolor flowers on thermal burn induced by UVB irradiation and to perform gel stability study.

METHODS

The antinociceptive and antiinflammatory effect were evaluated by static and dynamic mechanical allodynia model, paw edema, and neutrophilic cell infiltration. Metabolites compounds were quantified by HPLC. The gel stability study was performed analyzing organoleptical aspects, besides pH, viscosity, and quantification of rutin by HPLC.

RESULTS

In the results were evidenced changes in threshold in statical and dynamic mechanical allodynia (I(max)=100 ± 10% and 49 ± 10%, respectively), paw edema (I(max)=61 ± 6%), and myeloperoxidase activity (I(max)=89 ± 5%). Such effects may be attributed, in part, to rutin, salicylic and chlorogenic acids, and others compounds found in this species. No important changes were detected in the stability study, in all aspects analyzed in temperature below 25 °C.

CONCLUSION

These findings suggest that Viola tricolor gel has an antinociceptive and antiinflammatory effect in the ultraviolet-B-induced burn, since maintain the temperature below 25 °C.

Genotoxic effects of Campomanesia xanthocarpa extracts on Allium cepa vegetal system

CONTEXT. Campomanesia xanthocarpa Berg. (Myrtaceae), popularly known in Brazil as guabiroba, is a plant used as antidiarrheic, anti-inflammatory and antirheumatic agents, and in stomach and hepatic disorders.

OBJECTIVE

The antiproliferative and genotoxic effects of aqueous extracts and essential oil of C. xanthocarpa were evaluated.

MATERIALS AND METHODS

Cytotoxicity and genotoxicity of the aqueous extracts (6 and 30 mg/mL) and essential oil (0.25%, v/v) obtained from leaves of C. xanthocarpa were evaluated using the Allium cepa L. (Amaryllidaceae) assay. Mitotic index was calculated as the percentage of dividing cells of total cells observed; chromosome abnormalities were observed and counted during cell division. Additionally, the composition of the essential oil and the quantification of the main compounds of the extracts were determined by gas chromatography/mass spectrometry and high performance liquid chromatography coupled with diode array detector, respectively.

RESULTS AND DISCUSSION

Aqueous extracts (6 and 30 mg/mL) led to a reduction of 67.7% and 34.1% of the mitotic index, respectively, whereas the treatment with essential oil caused a 48.2% reduction in the mitotic index, when compared with negative control. Chromosomal mutations were observed and included anaphase bridges, delay chromosome, break chromosome, as well as metaphase with disorganized chromosomal and binuclear cells. The main compounds of the essential oil were β-caryophyllene (8.87%), viridiflorol (6.40%), spathulenol (5.16%), δ-cadinene (4.92%), linalool (4.46%) and α-cadinol (4.25%). Gallic acid (3.19%), chlorogenic acid (1.04%), quercetin (2.97%) and rutin (4.82%) were identified in an aqueous extract (30 mg/mL).

CONCLUSION

Our results demonstrated that genotoxic and antiproliferative activities are present in C. xanthocarpa infusions using the in vivo onion root-tip cell test.

Effect of black grape juice against heart damage from acute gamma TBI in rats

The aim of this study was to evaluate the potential positive effect of black grape juice (BGJ) on lipid peroxidation considering Total Body Irradiation (TBI) in Wistar rats. As a potential feasible means of evaluation in situ, blood serum lactate dehydrogenase (LDH) levels were evaluated as a marker for heart damage from acute radiation syndrome (ARS). Twenty rats were divided into four groups, two of them being irradiated by gamma-rays from a Co-60 source. Animals were treated by gavage with 2 mL per day of BGJ or placebo for one week before and 4 days after 6 Gy whole body gamma-irradiation, when they were euthanasiated. LDH on serum and lipid peroxidation on heart tissue were evaluated. High concentration of metabolites from lipid peroxidation in heart, and high LDH level on serum were found only in gamma-irradiated group given placebo, mainly at the first 24 h after radiation. Phytochemical analysis of BGJ was performed by determining total phenolics, flavonoids, and tannins followed by a high-performance liquid chromatography (HPLC/DAD) analysis, which showed resveratrol as the major constituent. Results suggest that BGJ is a good protective candidate compound against heart damage from ARS and its effects suggest its use as a radiomodifier.

In vitro antioxidant activity and effect of Parkia biglobosa bark extract on mitochondrial redox status

Aqueous-methanolic extract of Parkia biglobosa bark (PBB) was screened for its polyphenolic constituents, in vitro antioxidant activity, and effect on mitochondria redox status. The in vitro antioxidant activity was assessed by using the scavenging abilities and the reducing powers of 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) diammonium salt radical cation against Fe(3+). Subsequently, the ability of PBB to inhibit lipid peroxidation induced by FeSO(4) (10 μm) and its metal-chelating potential were investigated. The effects of the extract on basal reactive oxygen species (ROS) generation and on the mitochondrial membrane potential (ΔΨm) in isolated mitochondria were determined by using 2', 7'-dichlorodihydrofluorescin (DCFH) oxidation and safranin fluorescence, respectively. PBB mitigated the Fe(II)-induced lipid peroxidation in rat tissues and showed dose-dependent scavenging of DPPH (IC(50): 98.33 ± 10.0 μg/mL) and ABTS. (trolox equivalent antioxidant concentration, TEAC value = 0.05), with considerable ferric-reducing and moderate metal-chelating abilities. PBB caused slight decreases in both the liver and the brain mitochondria potentials and resulted in a significant decrease (p < 0.001) in DCFH oxidation. Screening for polyphenolics using high-performance liquid chromatography coupled to a diode array detector (HPLC-DAD) revealed the presence of caffeic acid, gallic acid, catechin, epigalocatechin, rutin, and quercetin. These results demonstrate for the first time the considerable in vitro antioxidant activity and favorable effect of PBB on mitochondria redox status and provide justification for the use of the plant in ethnomedicine.

African eggplant (Solanum anguivi Lam.) fruit with bioactive polyphenolic compounds exerts in vitro antioxidant properties and inhibits Ca(2+)-induced mitochondrial swelling

OBJECTIVE

To evaluate the antioxidant and radical scavenging activities of Solanum anguivi fruit (SAG) and its possible effect on mitochondrial permeability transition pore as well as mitochondrial membrane potential (ΔΨm) isolated from rat liver.

METHODS

Antioxidant activity of SAG was assayed by using 2,2-diphenyl-1-picrylhydrazyl (DPPH), reducing power, iron chelation and ability to inhibit lipid peroxidation in both liver and brain homogenate of rats. Also, the effect of SAG on mitochondrial membrane potential and mitochondrial swelling were determined. Identification and quantification of bioactive polyphenolics was done by HPLC-DAD.

RESULTS

SAG exhibited potent and concentration dependent free radical-scavenging activity (IC50/DPPH=275.03±7.8 μg/mL). Reductive and iron chelation abilities also increase with increase in SAG concentration. SAG also inhibited peroxidation of cerebral and hepatic lipids subjected to iron oxidative assault. SAG protected against Ca(2+) (110 μmol/L)-induced mitochondrial swelling and maintained the ΔΨm. HPLC analysis revealed the presence of gallic acid [(17.54±0.04) mg/g], chlorogenic acid (21.90±0.02 mg/g), caffeic acid (16.64±0.01 mg/g), rutin [(14.71±0.03) mg/g] and quercetin [(7.39±0.05) mg/g].

CONCLUSIONS

These effects could be attributed to the bioactive polyphenolic compounds present in the extract. Our results suggest that SAG extract is a potential source of natural antioxidants that may be used not only in pharmaceutical and food industry but also in the treatment of diseases associated with oxidative stress.

HPLC analysis of phenolics compounds and antioxidant capacity of leaves of Vitex megapotamica (Sprengel) Moldenke

Vitex megapotamica (Sprengel) Moldenke belongs to the Verbenaceae family and is popularly known as "tarumã". The antioxidant capacity of fractions and crude extract from the leaves of V. megapotamica were determined in this study through the capacity to remove reactive species and phenolic compounds were quantified in the various fractions. The IC50 (DPPH) ranged from 14.17 ± 0.76 to 37.63 ± 0.98 µg/mL. The ethyl acetate fraction might contain the strongest lipid peroxidation inhibitory compounds with an IC50 of 16.36 ± 5.09 µg/mL, being also the one with the highest content of polyphenols (522.4 ± 1.12 mg/g), flavonoids (220.48 ± 0.30 mg/g) and condensed tannins (3.86 ± 0.53 mg/g). Compounds quantified by HPLC/DAD in the crude extract and fractions were chlorogenic and rosmarinic acids. Higher dosages of the extracts were more effective in reducing levels of plasma protein carbonyls and were also shown to be able to remove reactive species by a 2',7'-dichlorofluorescein diacetate assay, reducing oxidative stress in all tested fractions. Results obtained indicated that V. megapotamica exhibits good potential to prevent diseases caused by the overproduction of free radicals and it might also be used as a potential source of natural antioxidant agents.

Hepatotoxicity evaluation of aqueous extract from Scutia buxifolia

Nowadays there is an increase in the number of people taking herbals worldwide. Scutia buxifolia is used for the treatment of hypertension, but little is known about its action on liver. Thirty-two Wistar rats were divided into four groups: control and groups treated during 30 days with 100, 200 and 400 mg of lyophilized aqueous extract of S. buxifolia (SBSB)/kg of body weight. This study was planned to explore hepatotoxic effect of SBSB, which was assessed by serum transaminases (ALT and AST). Thiobarbituric acid reactive substances (TBARS) levels were determined in liver, along with thiols content (NPSH), catalase (CAT) activity and, superoxide dismutase (SOD) enzymes. Histopathological studies of liver tissue were performed. Flavonoids and phenolics were quantified in SBSB by high performance liquid chromatography with diode array detection (HPLC/DAD). We did not observe alterations on redox status (TBARS, NPSH, CAT and, SOD) in the control and experimental groups. An increase on AST activity was only observed at 200 mg of SBSB, whereas ALT score was not affected by SBSB. Moreover, no morphological alterations were observed on the hepatocytes, matching the analysed biochemical parameters. This way, we conclude that SBSB was not toxic.

Antinociceptive and anti-inflammatory effects of Aloe saponaria Haw on thermal injury in rats

ETHNOPHARMACOLOGICAL RELEVANCE

In Brazil, the plant Aloe saponaria Haw, popularly known as "babosa pintadinha", has been empirically used for its potential effect on thermal injury. Because there are no scientific data confirming its popular use, the aim of the present study was to investigate the effects of Aloe saponaria on nociceptive and inflammatory parameters in a rat model of thermal injury.

MATERIALS AND METHODS

Adult male Wistar rats were subjected to a thermal injury or sham procedure (immersion in water at 70 or 37°C, respectively, for 5 or 8s). Burned animals were topically treated with vehicle (base cream), sulfadiazine 1% (positive control) or Aloe saponaria cream (0.3%-30%) once a day for 2 or 6 days. Each day, 30min before the treatment, we measured nociceptive (static and dynamic mechanical allodynia, thermal allodynia and spontaneous pain) and inflammatory (paw edema) parameters. Moreover, enzymatic indicators of leukocyte infiltration into burned tissue were also determined 2 or 6 days after the thermal injury.

RESULTS

The thermal injury (fist and second-degree) procedure, but not the sham procedure, induced nociception and inflammation from 1 to 6 days after the injury. The topical treatment with Aloe saponaria cream (10%) reduced nociceptive behaviors from day 1 to 6 (peak at day 2), edema at days 5 and 6 (peak at day 6) and myeloperoxidase, N-acetyl-glucosaminidase and eosinoperoxidase activities at day 6. The antinociceptive and anti-inflammatory effects of Aloe saponaria were obtained with doses of 3%-30%, with maximal inhibition obtained with a dose of 10% (reductions of 39±9%, 41±9%, 31±7%, 83±7% and 23±2% for static and dynamic mechanical allodynia, thermal allodynia, spontaneous pain and paw edema, respectively).

CONCLUSION

Our results demonstrate that topically applied Aloe saponaria presented antinociceptive and anti-inflammatory effects in rats subjected to a thermal injury, which supports its traditional use for burn injuries.