Ricardo Luiz Cavalcanti de Albuquerque Júnior

Efficacy of marigold extract‐loaded formulations against UV‐induced oxidative stress

The present study investigated the potential use of topical formulations containing marigold extract (ME) (Calendula officinalis extract) against ultraviolet (UV)B irradiation-induced skin damage. The physical and functional stabilities, as well as the skin penetration capacity, of the different topical formulations developed were evaluated. In addition, the in vivo capacity to prevent/treat the UVB irradiation-induced skin damage, in hairless mice, of the formulation with better skin penetration capacity was investigated. All of the formulations were physically and functionally stable. The gel formulation [Formulation 3 (F3)] was the most effective for the topical delivery of ME, which was detected as 0.21 μg/cm(2) of narcissin and as 0.07 μg/cm(2) of the rutin in the viable epidermis. This formulation was able to maintain glutathione reduced levels close to those of nonirradiated animals, but did not affect the gelatinase-9 and myeloperoxidase activities increased by exposure to UVB irradiation. In addition, F3 reduced the histological skin changes induced by UVB irradiation that appear as modifications of collagen fibrils. Therefore, the photoprotective effect in hairless mice achieved with the topical application of ME in gel formulation is most likely associated with a possible improvement in the collagen synthesis in the subepidermal connective tissue.

Acute and sub-acute oral toxicity of Brazilian red propolis in rats

ETHNOPHARMACOLOGICAL RELEVANCE Propolis is a bee product widely used in folk medicine due to its numerous pharmacological properties. However, samples from different regions can differ in chemical composition, effectiveness, and side effects. Despite the widespread use of Brazilian red propolis, which is an isoflavone-rich variety, its toxicity has not been carefully studied. AIMS OF THE STUDY To assess the acute and sub-acute toxicity of the hydroethanolic extract of red propolis (HERP) administered orally to rats. MATERIALS AND METHODS HERP for the acute (300mg/kg) and sub-acute (10, 100 and 200mg/kg) toxicity studies was administered orally to rats according to OECD Guidelines 420 and 407, respectively. Clinical signs were identified, and hematological and biochemical analyses were performed. Water and food uptake as well as body and organ weights of animals were recorded. RESULTS AND CONCLUSIONS The acute study revealed no lethal effects at 300mg/kg of HERP, but toxic signs were observed, as HERP had an LD50 of more than 300mg/kg, indicating a warning. The most toxic signals in sub-acute studies were observed in males at a dose of 200mg/kg HERP. These results suggest estrogen-like activity, possibly from the isoflavones in HERP.

Effect of green propolis on oral epithelial dysplasia in rats

UNLABELLED Studies have demonstrated that flavonoid compounds of green propolis have antitumoral activity. STUDY DESIGN Experimental study. AIMS To evaluate the effect of a hydroalcoholic extract of green propolis (EPV) on chemically induced epithelial dysplasias in rat tongues. METHODS AND MATERIALS DMBA was brushed on the lingual dorsum of rats 3x/week on alternate days--100 (PROP1), 200 (PROP2) and 300 mg/kg (PROP3) EPV was administered orally for 20 weeks. EPV or DMBA were replaced by their vehicles and applied as positive (TUM1 and TUM2) and negative controls (CTR1 and CTR2), respectively. The lingual epithelium was histologically analyzed and graded according a binary system and the WHO classification; the data were compared using ANOVA (*p<0.05). RESULTS The EPV yield was 41% and the flavonoid yield was 0.95±0.44%. According to the Binary System, TUM1, TUM2 and PROP1 were considered high risk lesions, with significantly higher morphological alteration rates compared to the other groups (p<0.05), which were considered low risk lesions. Based on the WHO classification, moderate dysplasia was TUM1 and TUM2, mild dysplasia was PROP1, PROP2 and PROP3, and non-dysplastic epithelium was CTR1 and CTR2. CONCLUSION EPV seems to play an important protective role against chemically-induced lingual carcinogenesis in rats.

Assessment of antinociceptive, anti-inflammatory and antioxidant properties of Cymbopogon winterianus leaf essential oil

The present study investigated the antinociceptive, anti-inflammatory and antioxidant effects of the leaf essential oil (LEO) of Cymbopogon winterianus Jowitt (Poaceae). In the acetic acid-induced writhing and formalin tests, the LEO (50, 100, and 200 mg/kg, p.o.) significantly reduced (p < 0.05) the number of writhings and paw licking times in the first (0-5 min) and second (15-30 min) phases, respectively. In contrast, the LEO did not alter the latency time for mice licking the rear paws in hot-plate test. The LEO inhibited the carrageenan-induced neutrophil migration to the peritoneal cavity in a dose-dependent manner (35.5%, 42.8%, and 66.1% at doses of 50, 100, and 200 mg/kg, respectively, p < 0.001). Moreover, LEO exhibited higher scavenging activity toward 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals with an IC50 (12.66 ± 0.56 μg/mL). Our present results demonstrated that the LEO has antinociceptive, anti-inflammatory, and antioxidant properties.

UVA-UVB Photoprotective Activity of Topical Formulations Containing Morinda citrifolia Extract

Exposure to solar radiation, particularly its ultraviolet (UV) component, has a variety of harmful effects on human health. Some of these effects include sunburn cell formations, basal and squamous cell cancers, melanoma, cataracts, photoaging of the skin, and immune suppression. The beneficial photoprotective effects of topical formulations with the extract, Morinda citrifolia, have not been investigated. This present study aims to investigate the potential benefits of M. citrifolia topical application on the dorsal skin of mice, exposed to UVA-UVB light. Using 7 days of treatment, [before (baseline values) and 20 h after UV exposure], the thickness, skin barrier damage (TEWL), erythema, and histological alterations were evaluated. The results showed that the formulations containing the extract protected the skin against UV-induced damage.

Hydroalcoholic extract of red propolis promotes functional recovery and axon repair after sciatic nerve injury in rats

Abstract Context: Peripheral axon injury and degeneration are often mediated by oxidative stress and inflammation. The hydroalcoholic extract of the red propolis (HERP) has attracted great attention because of its antioxidant and anti-inflammatory activities. Objective: The objective of this work is to study the effect of HERP on nerve repair and functional recovery after sciatic nerve injury (SNI) in rats. Materials and methods: The chemical markers in HERP were identified using high-resolution mass spectroscopy. After axonotmesis of sciatic nerve, ibuprofen (IBP) and HERP treatments were orally administered for 28 d. Behavioural tests were performed weekly after SNI. The myelinated axon number was counted using morphometric analysis. Results: The compounds found in HERP were pinocembrin, formononetin, vestitol, and biochanin A. The animals that underwent SNI showed a significant decrease in motor function based on the Basso, Beattie and Bresnahan scale and sciatic functional index compared with sham animals until 7 d after the surgery (p < 0.05). After 14 and 21 d, the SNI groups treated with either HERP or IBP showed significant improvement (p < 0.01), and the SNI group treated with HERP 10 mg/kg showed accelerated motor recovery compared with the other groups (p < 0.01). SNI caused also a reduction in the myelinated axon counts, and treatment with HERP 10 mg/kg induced a significant increase in the number of myelinated fibres compared with all other groups. Conclusion: HERP promoted regenerative responses and accelerated functional recovery after sciatic nerve crush. Thus, it can be considered to be a new strategy or complementary therapy for treating nerve injuries.

Estudo da ação antibacteriana do extrato hidroalcoólico de própolis vermelha sobre Enterococcus faecalis

Introduction:Propolis is a complex resinous substance produced by bees that has therapeutic properties, such as antimicrobial activity, anti-inflammatory, healing. Few studies exist on the red variety of propolis, found in the state of Sergipe.Objective:Evaluation of the antimicrobial action of the extract of propolis red collected in the northeastern state of Sergipe, against strains of Enterococcus faecalis.Material and method:The red propolis samples were collected in Brejo Grande/SE – Brazil and identified according to their sensory characteristics, granulometry and physical chemical requirements. The content of flavonoids in dried extract was determined. Solutions of red propolis (EEP) were prepared at concentrations of 1%; 2.5%; 5% and 7.5%. The bacterial strain used was Enterococcus faecalis – ATCC 29212. The antibacterial activity was verified by in vitro tests (disk diffusion test and determination of minimum bactericidal concentration – CBM) and ex vivo (using human extracted teeth). The test, ex vivo contaminated teeth were divided into three groups with 10 teeth each. Group 1 was treated with propolis to 7.5% (concentration determined in CBM test), the Group 2 was treated as positive control with sodium hypochlorite solution 2.5% and Group 3 was used as a negative control and was treated only with sterile saline.Result:The extract of propolis promoted inhibition zone compared to results from solution of sodium hypochlorite to 2.5%, showing values between 12 and 16 mm. There was no bacterial growth after root conduct irrigation with EEP to 7.5%.Conclusion:Propolis collected showed medium content of flavonoids (1.8%) and physical chemical characteristics consistent to those required by the Brazilian Government. At 7.5% of propolis extract, we observed a higher antibacterial potential than others groups.

Chemopreventive Effect of Brazilian Green Propolis on Experimental Dermal Carcinogenesis in Murine Model

El objetivo de este estudio fue evaluar el efecto de la administracion oral de extracto hidroalcoholico del propoleos verde (HEGP) sobre la carcinogenesis dermica en modelo de roedores. Para el ensayo biologico, se utilizaron 36 ratones asignados en 6 grupos (n = 6): CTR (tratado con 100 mg/kg HEGP y sin induccion de tumores), TUM (tratada con agua e induccion de tumores), GP10 (tratado con 10 mg/kg HEGP e induccion de tumores), GP50 (tratado con 50 mg/kg HEGP e induccion de tumores) y GP100 (tratado con 100 mg/kg HEGP e induccion de tumores). La induccion de cancer se llevo a cabo en la region dorsal de los ratones por aplicacion topica de DMBA. Despues de 16 semanas, los ratones fueron sacrificados y sus dorsos fueron sometidos a analisis histologico post-mortem. El numero medio de lesiones desarrolladas en TUM (4,14±0,89) fue significativamente mayor que GP10 (2,05±1,02), GP50 (1,8±1,92) y gp100 (2,5±1,73) (p<0,05). Los tumores formados en grupos tratados con HEGP fueron histologicamente mas diferenciados, pero solo en PV100 las lesiones in situ fueron manifiestas. La infiltracion de las estructuras anatomicas blanco fue menos frecuente en los grupos tratados con HEGP (p<0,05). Nuestros datos sugieren que la administracion oral de HEGP proporciona una inhibicion parcial de la carcinogenesis dermica inducida por DMBA, asi como parecio modular la diferenciacion y potencial infiltrante de los carcinomas en el modelo animal.

The effect of the aqueous extract Peumus boldus on the proliferation of hepatocytes and liver function in rats submitted to expanded hepatectomy

PURPOSE: To assess the effect of aqueous extract of Peumus Boldus (AEPB) on the liver proliferative response after parcial hepatectomy of 70% (PH) in rodents. METHODS: Twenty Wistar rats were divided in two groups: AEPB100 (whose rats received 100mg/Kg of AEPB, once a day, orally, in 4 days prior to the first surgical procedure) and Vehicle (whose rats were treated similarly with distilled water). Both groups underwent PH. After 24 hours the remaining livers were removed for studying the proliferation of hepatocytes by Ki-67 and 2mL of blood were collected for serological assessment: cholesterol, glucose, triglycerides, aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, and total, direct and indirect bilirubin. All data were analyzed by Gaussian distribution. Statistically significant differences between mean values were analyzed using T Students test. Non-Gaussian data were analyzed using Mann-Whitneys test. RESULTS: The liver of all these rats presented positive staining of Ki-67, indicating liver proliferation. Laboratory results showed no significant difference in serum values between the analyzed groups. The analysis of Ki-67 was significantly more positive in AEPB100 group than in Vehicle group. CONCLUSION: Aqueous extract of Peumus Boldus acute administration exerts significant positive effect on liver regeneration after 24h in rats that underwent parcial hepatectomy, while maintaining unchanged hepatic function.

RETARDO NO DIAGNÓSTICO DO CÂNCER BUCAL: ENTENDENDO OS FATORES RELACIONADOS

Objective: To discuss the main factors related to delay in the diagnosis of oral cancer and its influence on prognosis. Method: This is a literature review conducted in the databases PubMed, SciELO and BIREME, for the period 2002 to 2012, with the keywords “oral cancer”, “head and neck cancer” and “delay”. We found 141 articles in MEDLINEPubMed, 05 in SciELO and 51 in BIREME. After reading the abstracts, thirty articles were selected for analysis. Results: Several factors related to the tumor, patient, professional and local health system may cause and influence the diagnostic delay. The total period of delay can vary from few days to years, however, the most often cited interval was between 3-4 months and the patient was responsible for most of this delay. Few studies have shown statistically the association between greater delay in diagnosis and more advanced stage of oral cancer. Conclusion: The oral cancer diagnostic delay still lasts long in Brazil and worldwide. From a statistical view, the literature remains controversial about the main factors related to this issue and about its influence on prognosis. DESCRIPTORES: Mouth neoplasms. Delayed diagnosis. Oral Medicine.