IMUNOMODULAÇÃO PELA PRÓPOLIS

Toxicity assessment of saline extract and lectin-rich fraction from Microgramma vacciniifolia rhizome

Microgramma vacciniifolia is broadly used in folk medicine but safety information is unavailable. Therefore, we evaluated the toxicity of a saline extract and a lectin-rich fraction of M. vacciniifolia rhizome. The extract showed hemolytic activity on mice erythrocytes at 1000 μg/mL, whereas the fraction promoted hemolysis (8.57-26.15%) at all tested concentrations (10-1000 μg/mL). Acute toxicity test in mice indicated an LD₅₀ of >5000 mg/kg. Hematological alterations and increased serum alkaline phosphatase level were observed in the treated animals. Transaminases and urea levels increased in the groups treated with the extract or fraction at 5000 mg/kg. Leukocyte infiltration was observed in the liver of extract-treated animals and in the liver and lungs of mice treated with the fraction. The kidneys of animals treated with the fraction at 5000 mg/kg presented hydropic degeneration. The extract and fraction did not induce oxidative stress in the liver and did not show genotoxicity, as examined by micronucleus and comet assays. In conclusion, the preparations were not lethal to mice but caused some signs of toxicity, mainly the fraction. The results indicated the need to evaluate the toxicity of M. vacciniifolia rhizome in other models and in chronic assays.

Red propolis and L-lysine on angiogenesis and tumor growth in a new model of hamster cheek pouch inoculated with Walker 256 tumor cells

Objective:

To evaluate the effect of red propolis and L-lysine on angiogenesis and tumor growth in a new model of hamster cheek pouch inoculated with Walker 256 tumor cells.

Methods:

The study consisted of two experiments with four groups each (total: 57 hamsters). In the experiment 1, the animals were inoculated with Walker tumor cells, followed by administration of test substances (red propolis 200mg/5mL/kg or L-lysine 150mg/kg) or control substances (gum arabic 5mL/kg or water 5mL/kg) for 10 days. The animals in the experiment 2 received red propolis, L-lysine, gum arabic or water at the same doses, for 33 days prior to inoculation of Walker tumor cells, followed by 10 days of treatment with the same substances. Based on single-plane images, angiogenesis was quantified (mean vascular area), in percentage, and tumor area (mm²) and perimeter (mm).

Results:

In the experiment 1, compared to animals receiving water, the mean vascular area expressed in percentage was significantly smaller in animal treated with propolis (p<0.05) and L-lysine (p<0.001).

Conclusion:

Both red propolis and L-lysine inhibited tumor angiogenesis in the new hamster cheek pouch model when administered after tumor inoculation.

Flavonoids: biological activities and therapeutic potential

Flavonoids have aroused much interest in research, since they present a great diversity of biological activities observed in vitro, such as: antioxidant effect, modulation of the enzymatic activity and inhibition of cellular proliferation, exerting beneficial effects on the organism, as well as the use of its therapeutic potential. With wide distribution in the plant kingdom represent a class of phenolic compounds that differ in their chemical structure and particular characteristics. The objective of this review was to describe the relevant aspects of flavonoids, reporting the different known groups, the probable mechanisms by which they act, their pharmacological properties and to gain a better understanding of the reported beneficial health effects of these substances. This systematic review consisted of research using scientific databases such as Scopus, Science Direct, PubMed, SciVerse and SciELO, without time limitation. Some pharmacological properties of some flavonoids and their health benefits have been confirmed by previous studies.

Chemical composition, immunostimulatory, cytotoxic and antiparasitic activities of the essential oil from Brazilian red propolis

Most studies of Brazilian red propolis have explored the composition and biological properties of its ethanolic extracts. In this work, we chemically extracted and characterized the essential oil of Brazilian red propolis (EOP) and assessed its adjuvant, antiparasitic and cytotoxic activities. The chemical composition of EOP was analyzed using gas chromatography with mass spectrometry (GC-MS). EOP was tested for in vitro activity against Trichomonas vaginalis (ATCC 30236 isolate); trophozoites were treated with different concentrations of EOP (ranging from 25 to 500 μg/mL) in order to establish the MIC and IC₅₀ values. A cytotoxicity assay was performed in CHO-K1 cells submitted to different EOP concentrations. BALB/c mice were used to test the adjuvant effect of EOP. The animals were divided in 3 groups and inoculated as follows: 0.4 ng/kg BW EOP (G1); 50 μg of rCP40 protein (G2); or a combination of 0.4 ng/kg BW EOP and 50 μg of rCP40 (G3). Total IgG, IgG1 and IgG2a levels were assessed by ELISA. The major constituent compounds of EOP were methyl eugenol (13.1%), (E)-β-farnesene (2.50%), and δ-amorphene (2.3%). Exposure to EOP inhibited the growth of T. vaginalis, with an IC₅₀ value of 100 μg/mL of EOP. An EOP concentration of 500 μg/mL was able to kill 100% of the T. vaginalis trophozoites. The EOP kinetic growth curve showed a 36% decrease in trophozoite growth after a 12 h exposure to 500 μg/mL of EOP, while complete parasite death was induced at 24 h. With regard to CHO-K1 cells, the CC₅₀ was 266 μg/mL, and 92% cytotoxicity was observed after exposure to 500 μg/mL of EOP. Otherwise, a concentration of 200 μg/mL of EOP was able to reduce parasite proliferation by 70% and was not cytotoxic to CHO-K1 cells. As an adjuvant, a synergistic effect was observed when EOP was combined with the rCP40 protein (G3) in comparison to the administration of each component alone (G1 and G2), resulting in higher concentrations of IgG, IgG1 and IgG2a. EOP is constituted by biologically active components with promising antiparasitic and immunostimulatory activities and can be investigated for the formulation of new vaccines or trichomonacidal drugs.

Fungal infection control by garlic extracts (Allium sativum L.) and modulation of peritoneal macrophages activity in murine model of sporotrichosis

Abstract Garlic (Allium sativum L.) is grown all over the world as seasoning and medicinal vegetable since 3,000 BC. Allicin is the main component of garlic, being attributed to it the most of its biological activities, such as bactericidal, antifungal and antiviral actions. However, other compounds of garlic present antioxidant, hypocholesterolemic, vasodilator activities, protective action against different types of cancer, and immunomodulatory. Fungal infections are important causes of morbidity and mortality in people mainly in immunosuppressed ones. Sporothrix schenckii, the causing agent of Sporotrichosis (most common subcutaneous mycosis in Latin America), is dimorphic fungus, of saprophytic life in soil or plants, infecting people and animals mainly through skin injuries and bruises. The main of this work was to evaluate the influence of garlic consuming on immune modulation of healthy and infected Swiss mice in induced way by S. schenckii, since these animals functioning of peritoneal macrophages as well as the nitric oxide and cytokines’ production (IL-1β, IL-10 and IL-12) and to evaluate the antifungal potential of garlic with S. schenckii through minimum inhibitory concentration test and colony-forming units. The results showed that garlic offers antifungal potential with S. schenckii. The oral taking of garlic extracts influences the releasing of cytokines by macrophages, regular consuming shows anti-inflammatory effect, and its acute use may take to an inflammatory response. Mice that consumed garlic responded more effectively to fight against the infection.

Action of Brazilian propolis on hematological and serum biochemical parameters of Blue-fronted Amazons (Amazona aestiva, Linnaeus, 1758) in captivity

The present study aimed to evaluate the effect of propolis use on hematological and serum biochemical parameters in Blue-fronted Amazons (Amazona aestiva). For this, 12 adult birds were distributed randomly into individual cages, divided into treatments with different propolis levels (A = 0.0%; B = 0.5%; and C = 1.0%), in 3 distinct phases (I, II, and III), with 15-d duration for phases I and III and 30 d for phase II, totaling 60 d. In phases I and III, all birds received treatment A ration, and in phase II received A, B, or C (4 birds per treatment). At the end of each phase, blood was collected for biochemical and hematological evaluations. The variables were analyzed by ANOVA (P < 0.05). Results suggest that 0.5% propolis reduced lactate dehydrogenase levels, whereas treatment B augmented hemoglobin concentrations and eosinophil count. It is concluded that 0.5% propolis improves levels of lactate dehydrogenase, hemoglobin, and eosinophils.

Comparative study of topical green and red propolis in the repair of wounds induced in rats

OBJECTIVE

To evaluate the healing action of green and red propolis, correlating it with the content of flavonoids.

METHODS

We performed quantification of total flavonoids of green and red propolis ethanol extracts for subsequent incorporation in ointment base to 20%. We used 20 Wistar rats divided into four groups: 0.9% saline (S), ointment base (B), green propolis ointment (G) and red propolis ointment (R). All animals were submitted to excisional lesions in the midian back region. The rats were treated daily for 15 days. During this period we observed weight, body temperature and diameters of the wounds. For histological analysis, samples were collected from wounds. At the end of the experiment we performed blood collection and removal of the kidney and liver for biochemical and histological analyzes.

RESULTS

The levels of total flavonoids of green (4.50%) and red (5.92%) propolis were high (> 2%), but, while the latter showed a content larger than the former, the evolution of green propolis was better in the repair of wounds, both macroscopically and histologically. There were no nephrotoxicity or hepatotoxicity, a result confirmed by biochemical tests (ALT and albumin). Propolis influenced the reduction of total cholesterol, triglycerides and glucose.

CONCLUSION

There was no correlation between total flavonoid contents and the healing action of propolis. This reveals the need for elucidation of the flavonoids found in each class of propolis to unravel which one(s) would be important for the healing process.

Chemoprevention with green propolis green propolis extracted in L-lysine versus carcinogenesis promotion with L-lysine in N-Butyl-N-[4-hydroxybutyl] nitrosamine (BBN) induced rat bladder cancer

PURPOSE

To determine the effects of green propolis extracted in L-lysine (WSDP) and of L- lysine for 40 weeks on induced rat bladder carcinogenesis.

METHODS

The animals (groups I, II, III, IV, V and VI) received BBN during 14 weeks. Group I was treated with propolis 30 days prior received BBN, and then these animals were treated daily with propolis; Groups II and III was treated with subcutaneous and oral propolis (respectively) concurrently with BBN. The animals of Group IV were treated L-lysine; Group V received water subcutaneous; and Group VI received only to BBN. Among the animals not submitted to carcinogenesis induction, Group VII received propolis, Group VIII received L-lysine and Group IX received water.

RESULTS

The carcinoma incidence in Group I was lower than that of control (Group VI). The carcinoma multiplicity in Group IV was greater than in Group VI. All animals treated with L-lysine developed carcinomas, and they were also more invasive in Group IV than in controls. On the other hand, Group VIII showed no bladder lesions.

CONCLUSION

The WSDP is chemopreventive against rat bladder carcinogenesis, if administered 30 days prior to BBN , and that L-lysine causes promotion of bladder carcinogenesis.

Brazilian green propolis: anti-inflammatory property by an immunomodulatory activity

The immunomodulatory and anti-inflammatory activities of green propolis extracts from Apis mellifera were investigated using acute and chronic inflammation models. Swiss mice were anesthetized and a cotton pellet granuloma was implanted in subcutaneous tissue. Then the mice were divided into six groups and received apyrogenic water or different propolis extracts by oral route (5 mg/kg). According to the treatment the groups were designated as E1A, E1B, E10, E11, and E12. The control group received apyrogenic water. The treatment was performed by six days when the mice were killed. The blood and the bronchoalveolar lavage (BAL) were collected to measure the leukocyte recruitment. In acute pulmonary inflammation, Balb/c mice received lipopolysaccharide (LPS) of Escherichia coli by intranasal route for three days. Concomitantly the mice received by oral route apyrogenic water (control) or E10 and E11 propolis extracts. BAL was performed to assess the inflammatory infiltrate and cytokine quantification. The results showed that the E11 extract has anti-inflammatory property in both models by the inhibition of proinflammatory cytokines and increase of anti-inflammatory cytokines suggesting an immunomodulatory activity.