Histological, immunohistochemical and biochemical effects of bee bread on stomach tissue of obese rats.

Obesity is a major health problem threatening humanity in medical, social and psychological dimensions. In this study, we aimed to determine the histological, immunohistochemical and biochemical effects of bee bread, added to diets of obese rats in different doses, on leptin and ghrelin expression. In the study, 40 female Sprague‒Dawley (200‒250 g) rats were randomly divided into 5 equal groups and then assigned to control and obesity groups. The obesity group consisted of four subgroups: high­fat diet group, 100 and 200 mg/kg/bw groups, and metformin group. Histopathological evaluation revealed structural deterioration and necrotic areas in the epithelium and glands of the obese rats' stomach tissue, while in their serum and gastric tissues, the MDA level was significantly higher than in the other groups. There was a negative correlation between leptin and ghrelin levels. Apoptotic cells increased with obesity, but the application of beebread was similarly effective as metformin administration in reducing this increase (Tab. 5, Fig. 4, Ref. 51). Keywords: bee bread, leptin, ghrelin, stomach, obesity, rat.

Effects of diets containing different concentrations of propolis on hematological and immunological variables in laying hens.

To evaluate the effect of 4 different levels of propolis supplementation on the hematological and immunological parameters of laying hens, a trial was conducted with 60 White Leghorn layer hens. The experiment was conducted by using a randomized design with 5 treatments, 4 replicates, and 3 hens in each replicate. Treatments included basal diet (control) and basal diet plus 0.5, 1, 3, and 6 g of propolis/kg of diet, respectively. At the end of the 12-wk treatment period, samples of blood were collected to determine hematological and immunological values. The results showed that the addition of propolis at 3 g/kg in the diet resulted in significant increases (P < 0.05) in the serum IgG and IgM levels and significant decreases (P < 0.05) in the peripheral blood T-lymphocyte percentage compared with those of the control and other treatment groups. In addition, the level of 3 g/kg of propolis supplementation significantly increased (P < 0.05) erythrocyte count (red blood cells) compared with the other treatments. On the other hand, hemoglobin and hematocrit values and total leucocyte (white blood cells) and differential leucocytes counts were not influenced by propolis supplementation. These results indicate that the inclusion of propolis at the level of 3 g/kg of diet may have a positive effect on humoral immunity of laying hens.

The cardiotoxic effects of acute and chronic grayanotoxin-III in rats.

The purpose of this study is to histologically and immunohistochemically determine the changes created by grayanotoxin-III (GTX-III), which is a sodium channel neurotoxin, on heart tissues in different dosages. Rats were randomly divided into 10 groups to determine the acute and chronic effects of GTX-III. While the rats in groups 1 and 6 were control rats, the rats in groups 2-5 (1, 2, 4, and 8 µg/kg bw GTX-III) received a single dose of intraperitoneal GTX-III, and the rats in groups 7-10 received GTX-III every day for 3 weeks. As a result of the trial, in the heart tissues, histopathological changes were determined by hematoxylin-eosin staining, interleukin-1 (IL-1ß), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and brain natriuretic peptide (BNP) were determined by the avidin-biotin peroxidase method, and apoptosis was examined by immunohistochemistry (IHC) analysis and the terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) staining method. In the immunohistochemistry sense, while the BNP level in the AGTX-III groups did not vary significantly, an increase in dosage significantly increased the IL-6, IL-1ß, and TNF-α levels in comparison to the control groups. In their comparison to the control groups, the BNP levels increase and the IL-6 and IL-1ß levels decreased in the CGTX-III groups. TUNEL analysis revealed that apoptosis increased in both the acute and chronic groups.

Acute effects of grayanotoxin in rhododendron honey on kidney functions in rats.

The aim of the study is to evaluate the acute biochemical and histological changes in rat kidneys after treatment with grayanotoxin (GTX) of rhododendron honey (RH). A total of 60 Sprague-Dawley female rats were divided into five groups of 12 rats each, one being a control group (group 1) and group 2 was treated with 0.015 mg/kg/bw of GTX standard preparation via intraperitoneal injection. Groups 3, 4, and 5 were given RH at doses of 0.1, 0.5, and 2.5 g/kg/bw, respectively, via oral gavage. Compared to the control group, significant increases were observed in glucose, blood urea nitrogen (BUN), and creatinine levels of the GTX-injected groups after 1 h. However, in low dose RH group, such an increase was not observed and had a normal appearance histologically. Therefore, low dose (1 g/kg/bw) of RH produces no acute adverse effects on renal functions of rats.

Effect of propolis on erythrocyte rheology in experimental mercury intoxication in rats.

In the present study, changes in erythrocyte rheology in association with mercury toxicity and the role of propolis were analyzed in rats. Forty male Wistar Albino rats that were 4-5 months old were used in the study. The control group was administered normal saline intraperitoneal (ip) injections; the mercury chloride group was administered HgCl2 (4 mg/kg, ip); the propolis group was administered propolis (200 mg/kg, by gavage); and the HgCl2+ propolis group was administered HgCl2 (4 mg/kg, ip) + propolis (200 mg/kg, by gavage) for 3 days. The following parameters were analyzed: hematological parameters, plasma potassium (K) levels, methemoglobin, 2,3-DPG, erythrocyte deformability, and hemolysis as a percentage. The results revealed that leukocyte count significantly increased, and a significant decline occurred in the platelet count (p < 0.01). Serum K(+), MetHb, 2, 3-DPG, and hemolysis percentage significantly increased in the rats exposed to mercury (p < 0.01). However, the values of rats administered only with propolis were close to the values of the control group and the changes were avoided by the administration of propolis as protection in the rats exposed to mercury chloride.

Comparative study of in vitro methods to analyse the antifungal activity of propolis against yeasts isolated from patients with superficial mycoses.

AIM: To test a total of 15 strains belonging to four species of yeasts by different in vitro methods against propolis and itraconazole (ITC). METHODS AND RESULTS: Three methods were compared for susceptibility testing of yeast isolates to propolis: disc diffusion method, agar dilution method and National Committee for Clinical Laboratory Standards (NCCLS, M27A) broth microdilution method. ITC was selected as the antifungal agent for comparison study. Using the broth microdilution method, the geometric mean for MIC (microg ml(-1)) with regard to all isolates was < or =0.06 for propolis and < or =0.35 for ITC. The broth microdilution and the agar dilution methods were in good agreement (75%) for propolis against yeasts isolated from patients with superficial mycoses. Using the diffusion method, all strains showed a broad zone of inhibition at the first available reading time (24 or 48 h). An increase of MIC values was accompanied by a decrease of growth inhibition zone diameter. A favourable correlation was found between MIC and inhibition zone around the disc for propolis sample and the correlation coefficient was: r = -0.626 (P < 0.01). CONCLUSIONS: This study suggests the potential value of the agar dilution and disc diffusion method as a convenient alternative method for testing of yeasts to propolis. SIGNIFICANCE AND IMPACT OF THE STUDY: This study demonstrated that propolis and ITC were very active against yeasts from patients with superficial mycoses. The other prominent finding in this study is that RPMI 1640 with L-glutamine was the available broth for the in vitro susceptibility testing of yeasts.

The anticarcinogenic effect of propolis in human lymphocytes culture.

The in vitro anticarcinogenic potential of propolis in human lymphocytes was investigated. Blood samples were obtained from ten healthy males, non-smoking volunteers, which were incubated and exposed to increasing concentrations of propolis (0.01, 0.05, 0.1, 0.2, 0.5, 0.7 and 1.0 ml). The mean micronucleus rates were 1.47 +/- 0.38 - 4.02 +/- 0.64. Mitotic index rates were between 19.45 +/- 2.22 and 0.28 +/- 0.33. The differences between the control and exposed cells were statistically significant (p < or = 0.05). We conclude that exposure to different concentrations of propolis cannot produce a carcinogenic effect in peripheral human lymphocytes in vitro. However, increasing micronucleus (MN) rates showed that propolis could have a carcinogenic effect in high concentrations. Also chemical analysis of propolis sample was evaluated by GC/MS. Propolis sample mainly contains flavonoids, fatty and aromatic acids and their esters.

Antibacterial activity of Turkish propolis and its qualitative and quantitative chemical composition.

The antibacterial activity of propolis from different regions of Turkey was studied, accompanied by TLC and GC-MS analyses of its chemical composition and spectrophotometric quantification of the most important active principles. All six samples were active against the bacterial test strains used; however, samples 1 (Yozgat), 2 (Izmir) and 3 (Kayseri) were more active than samples 4 (Adana), 5 (Erzurum) and 6 (Artvin). By TLC comparison all samples were found to contain poplar taxonomic markers but in samples 4 (Adana), 5 (Erzurum) and 6 (Artvin), different substances were observed, which were not present in P. nigra L. bud exudate. The typical poplar samples 1 (Yozgat), 2 (Izmir) and 3 (Kayseri) displayed very similar phenolic and flavonoid content. Samples 4 (Adana), 5 (Erzurum) and 6 (Artvin) were characterized by low phenolic and very low flavonoid concentrations. Qualitative analysis by GC-MS revealed that sample 4 (Adana) contained diterpenic acids and high percent of cinnamyl cinnamate, sample 5 (Erzurum)-significant amounts of hydroxy fatty acids and triterpenic alcohoLs, and sample 6 (Artvin)-phenolic glycerides, characteristic for the bud exudate of Populus euphratica Oliv. The results confirm the importance of phenolics for propolis antibacterial activity, and the significance of P. nigra L. as a propolis source, which provides the hive with the best defense against microorganisms.

Effect of propolis in the treatment of experimental Staphylococcus aureus keratitis in rabbits.

PURPOSE: The aim of this study was to investigate the antimicrobial and anti-inflammatory properties of an ethanolic extract of propolis, a natural resin produced by honeybees, and to determine synergistic activity between ciprofloxacin and propolis in the treatment of experimental Staphylococcus aureus keratitis. METHODS: Sixteen young New Zealand white rabbits were given intrastromal injections of S. aureus strains. Twenty-four hours later, the rabbits were randomly divided into 4 groups: group 1 was treated with topical 0.3% ciprofloxacin drops along with the ethanolic extract of propolis drops; group 2 received topical 0.3% ciprofloxacin drops; group 3 was administered the ethanolic extract of propolis drops, and group 4, the control group, was treated with phosphate-buffered saline (PBS) drops. Drugs were instilled 8 times/day for 72 h. Twenty-four and 96 h after inoculation of bacteria, the eyes were examined by slit lamp to assess corneal opacity. Corneas were removed to count bacteria. RESULTS: Slit lamp examination showed that the corneal opacity scores were significantly lower in eyes that received propolis plus ciprofloxacin than in those treated with ciprofloxacin (p = 0.041) or propolis (p = 0.006) or control eyes treated with PBS (p = 0.0001). There was no significant difference in eyes treated with ciprofloxacin and propolis (p = 1.00). There were significantly fewer bacteria in eyes that received propolis plus ciprofloxacin than in those treated with ciprofloxacin (p = 0.0001) or propolis (p = 0.0001) or control eyes treated with PBS (p = 0.0001). There was no significant difference in eyes treated with ciprofloxacin and propolis (p = 0.38). CONCLUSIONS: Taking these findings into consideration, we suggest that the ethanolic extract of propolis has antimicrobial and anti-inflammatory properties for S. aureus keratitis. The combination of ciprofloxacin and propolis had better therapeutic effects than either agent alone.

Comparison of in vitro activities of antifungal drugs and ethanolic extract of propolis against Trichophyton rubrum and T. mentagrophytes by using a microdilution assay.

The in vitro activities of propolis against 29 strains of dermatophytes were compared with those of terbinafine, itraconazole, ketoconazole, and fluconazole. Minimal inhibitory concentrations (MICs) were determined according to a National Committee for Clinical Laboratory Standards broth microdilution method. Among the systemic antifungals tested, terbinafine was the most potent. Propolis showed important antifungal activity and it merits further investigation as a potentially useful agent for the treatment of dermatophytosis.