Effect of aqueous extract of olive leaves on some biochemical changes induced by carbon tetrachloride in male rats

Olive tree leaves have been widely used in traditional remedies in European and Mediterranean countries and in the human diet as extracts, herbal teas, and powder, which contain several potential bioactive compounds that may have antihypertensive, antiatherogenic, anti-inflammatory, hypoglycemic, hypocholesterolemic, antidiabetic and antioxidant activities. The present study was carried out to evaluate the role of olive leaves extracts (OLE) in ameliorating the metabolic changes in rats treated with carbon tetrachloride (CCl4). Forty-eight male rats were classified into six groups; the first group was the control which received 1 ml distilled water, the second group was treated daily with oral dose of cold OLE (1 ml/kg) for one month, the third group was treated daily with oral dose of boiled OLE (1 ml/kg) for one month, the fourth group was treated daily with oral dose of CCl4 (1 ml/kg) for one month, the fifth group was treated with both cold OLE and CCl4 (1 ml/kg for each) for one month and the sixth group was treated with both boiled OLE and CCl4 (1 ml/kg for each) for one month. Serum levels of thiobarbituric acid reactive substance (TBARS), alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), gamma-glutamyl transferase (GGT), lactate dehydrogenase (LDH), urea, creatinine, insulin and glutathione (GSH), catalase (CAT), albumin, total protein, free triiodothyronine (FT3) , free thyroxin (FT4) were measured in serum. Histological examination of hepatic tissue was examined. The results showed that administration of CCl4 to rats induced significant increase (P<0.05) in serum levels of thiobarbituric acid reactive substance (TBARS), alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), gamma- glutamyl transferase (GGT), lactate dehydrogenase (LDH), urea, creatinine, insulin and significant decrease (P<0.05) in glutathione (GSH), catalase (CAT), albumin, total protein, free triiodothyronine (FT3) and free thyroxin (FT4). The histological examination of hepatic tissue showed some degenerative changes while significant improvement in biochemical and histological changes was observed either in CCl4 + cold OLE or CCl4 + boiled OLE groups. It could be concluded that the protective effect of olive leaves extract either cold or boiling may be attributed to its antioxidant properties. The obtained results indicated that both cold and boiled olive leaves extract has potent effect to restore the antioxidant status, hepato-renal function, insulin and thyroid hormones near to the control levels.

Modulation of claudins expression in the gastrointestinal tract by probiotics

The aim was to examine the expression of tight junction proteins, namely claudins 1 and 5 (CLD1 and 5) and the effects of probiotics-feeding on their expression in the gastrointestinal tract. In experiment 1, the expression of CLD1 and 5 was examined in chicks fed with starter rations for 7 days post-hatching. At day 7 the proventriculus, ileum, cecum and colon were collected for RT-PCR analysis of CLD1 and 5 gene expression. In experiment 2, the chicks were arranged in 3 groups: control group, probiotics group I and probiotics group II, which were fed with starter rations containing 0, 0.2 or 0.4% probiotics, respectively, for 14 days. The proventriculus, ileum, cecum and colon were collected in all groups at D0, D7 and D14 for analysis of CLD1 and 5 expressions by real time PCR. The expressions of CLD1 and 5 were detectable in all segments. Probiotics-feeding did not affect the expression of the CLD1 at D7 and D14 in the proventriculus, ileum and cecum. However, in the colon the expression of CLD1 was higher in probiotic group I than control and probiotics group II. The expression of CLD5 did not show significant differences except in the colon at D7 where control group was higher than that of D0 and D14 and higher in probiotic group I than probiotics group II. These results suggest that probiotics-feeding may not have effects on the gene expressions of CLD1 and 5 in the proventriculus, ileum and cecum. In contrast, probiotics-feeding may enhance the expression of CLD1 in the colon of broiler chicks. This result suggest that probiotics-feeding enhanced the expression of CLD1 in the colon and may help in maintaining tight junction functions and reducing the risk by pathogenic invasions.

Isolation and Characterization of metabolites from Clathria procera Ridley extract and Evaluation of its antidiabetic ef-fects in Streptozotocin-induced diabetic rats

Diabetes mellitus is a lethal metabolic disorder in humankind, which induce chronic complications. The present study investigated the effects of ethyl acetate extract from C. procera (EAE) and its isolates on antioxidant and in vitro antidiabetic activities, along with effects of EAE on plasma blood glucose concentrations in STZ-diabetic rats. For the first time, two known metabolites- N-((2S,3R,E)-1,3-dihydroxyoctadec-4-en-2-yl)stearamide (1) and N-((2S,3R,4E,8E)-1,3-dihydroxyoctadeca-4,8-dien-2-yl)palmitamide (2) are reported from EAE. 1, 2 and EAE depicted significant DPPH, superoxide free radicals, α-glucosidase and α-amylase inhibitory profile, indeed, 1 and 2 showed mild inhibitory profile against aldose reductase. In addition, the EAE (200 mg/kg b.w) revealed significant reduction in plasma glucose, body weight, total cholesterol, total glycerides and LDL levels in STZ-induced diabetic rats. The HDL levels were markedly augmented in EAE treated diabetic rats, when compared with control group. EAE abolished the increased lipid peroxidation in pancreas, liver and kidneys. The histopathological examination of pancreas of EAE protected the Langerhans islets with the number of islet cells were found statistically significant, when compared to diabetic control pancreas. Our data suggest that the C. procera has a potentiality to act against diabetes (both, in vitro and in vivo models) by inhibiting particularly digestive enzymes namely α-glucosidase and α-amylase, however further studies are required for proper establishment of mechanism of action and validating clinical effects.

Antibiotic resistance profiles of Staphylococci of animal and human origin

The emergence of multidrug-resistant bacteria in animals and their products has highlighted the considerable value of the potential transfer of resistance to the human population via the food chain. The objective of this work was to study the antibiotic resistance profile of staphylococci of human and animal origin and to compare the two profiles in order to define an effective therapeutic and preventive strategy. This work was carried out on a set of 97 strains of staphylococci isolated from animal and human biological liquids. The isolation and identification was done by conventional methods. The determination of the minimum inhibitory concentrations (MIC) was studied by the reference method (dilution in agar medium) and VITEK 2® with respect to eight (8) antibiotic molecules. The results were interpreted according to the ACFSM criteria (2001). The results showed higher resistance of human bacteria to penicillin (72.22% vs. 30.23%) erythromycin (50% vs. 18.6%) and gentamicin (33.33% vs. 9.3%) compared to animal bacteria. On the other hand, the resistance to fosfomycin of staphylococci of animal origin was higher (60.46%) compared to human strains (38.89%). Indeed, it seems that vancomycin and rifampicin are the antibiotics of choice against these pathogenic strains in veterinary and human medicine.

Molecular characterization of ochratoxin A-producing fungi isolated from poultry feed

Mycotoxins are toxic metabolites mainly produced by Aspergillus spp. fungi. Further fungal characterization and mycotoxin estimation in feed are crucial measures for animal health and safety. The aim of this study was to identify and characterize mycotoxin-producing fungi in poultry feed. Forty poultry ration samples were collected and were subjected to morphological and molecular as well as to phylogenetic analyses of Aspergillus section Nigri. On average, 40% (16 of 40 samples) were contaminated with Aspergillus section Nigri fungi. Moreover, A. niger and A. tubingensis were identified and characterized in the contaminated poultry feed using molecular and phylogenetic analyses. Furthermore, our results showed that ochratoxin A was produced by some fungal isolates indicating their mycotoxigenicity. In conclusion, A. niger and A. tubingensis contaminate poultry feed and can produce mycotoxins under optimal conditions. Furthermore, several preventive and control measures should be undertaken to reduce the occurrence of fungal contamination and toxin production in poultry rations.

A novel rat model of foreign body osteomyelitis for evaluation of antimicrobial efficacy

The most common organism-type causing orthopedic foreign body infection is the staphylococci, of which Staphylococcus aureus and Staphylococcus epidermidis are especially common. These organisms form biofilms on orthopedic foreign body surfaces, rendering such infections challenging and time consuming to treat. Our group evaluates novel therapeutics for orthopedic foreign body infection in animal models. A current limitation of most animal models is that that they only allow for the removal of one sample per animal, at the time of sacrifice. Herein, we describe a novel rat model of foreign body osteomyelitis that allows removal of foreign bodies at different time points, from the same infected animal. We demonstrate that this model can be used for both S. aureus and S. epidermidis orthopedic foreign body infection, with 3.56, 3.60 and 5.51 log10 cfu/cm2 S. aureus recovered at four, five and six weeks, respectively, after infection, and 2.08, 2.17 and 2.62 log10 cfu/cm2 S. epidermidis recovered at four, five and six weeks, respectively, after infection. We evaluated the model with S. aureus infection treated with rifampin 25 mg/kg twice daily for 21 days. Using quantitative cultures, we were no longer able to detect bacteria as of the 14th day of treatment with bacteria becoming detectable again 7 days following the discontinuation of rifampin a period. This novel model allows monitoring of evolution of infection at the infection site in the same animal.

Acute hyperglycemia does not alter the exploratory behavior of adult zebrafish (Danio rerio)

The acute effects of hyperglycemia in cognitive function and mood are not well elucidated. The aim of this study was to evaluate whether acute hyperglycemia alters the exploratory behavior of adult zebrafish. Fish were maintained aquariums containing 55 mM D-glucose solution for 14 days. Blood glucose levels and behavioral analysis were assessed before and after the D-glucose challenge. Immersion of adult zebrafish in a 55 mM D-glucose solution (14 days) increased blood glucose levels until the 14th day. There was no difference in weight gain between the two groups. Hyperglycemia did not induce anxiogenic or anxioly-tic behavior, nor did it alter the locomotor activity of the animals. We conclude that acute hyperglycemia does not alter the exploratory behavior of the adult zebrafish.

Excitatory and inhibitory influence of exogenous neurotransmitters on reproduction in female rats

Neurotransmitters are mediators inside the nervous system responsible for transmitting neural-neural or neural-organs signals. Several neural studies have tried to unveil the role of such mediators whose action extended outside the nervous system such as immune, digestive, circulatory and reproductive systems. The present study aimed to investigate the role of the excitatory-glutamate and inhibitory-GABA transmitters in female rats reproduction including their effects on gonadotropins; luteinizing hormone (LH) and follicle stimulating hormone (FSH) and the sex steroids; estrogen (E2) and progesterone (P4) during the estrous cycle as well. Furthermore, the responsive changes on the ovarian tissue were also studied. Synthetic glutamate and GABA were injected intraperitoneally (ip) in those animals throughout four successive estrous cycles. Interestingly, the ip injections of glutamate increased the levels of LH, E2 and P4 but decreased those of FSH significantly. However, the ip injections of GABA significantly decreased the levels of LH in the 4th cycles and FSH throughout treatment period while it increased the levels of E2 and P4. All changes occurred in those reproductive hormones caused by glutamate has been recovered after cessation of glutamate and GABA injection except FSH, including; the 5th, 6th and 7th cycles. Regarding to histopathological examination, ovaries of treated rats showed deleterious changes. The glutamate-treated rats ovaries showed atrophy of the primary follicles with degenerative changes in those secondary and tertiary follicles with obvious degeneration in the granulosa cell layer with vacuolated cytoplasm. On the other hand, those received GABA showed degeneration of the oocytes with congestion of blood vessels supplying the corpora lutea (CL) associated with endothelial changes. The histopathological changes in CL have been improved after glutamate cessation while not changed after GABA cessation.

Aflatoxin induced renal toxicity in Albino rats and the ameliorative effect of green tea aqueous extract: Histological, Morphometric and Immuno-histochemical Study

Tea is the most common drink worldwide besides water. It is rich in antioxidant polyphenolic flavonoids. Further, it has anti-apoptotic, anti-inflammatory, and autoantigen-inhibitory properties. To evaluate the effects of oral administration of aqueous extract of green tea against experimental aflatoxicosis on the renal tissues of adult male albino rats. Twenty five adult male rats were included and they were divided equally into 5 groups: Group 1 (aflatoxin group): the rats received aflatoxins (2.5 mg/kg diet for 15 days), group 2 (aflatoxins and green tea aqueous extract group) for 15 days, group 3, the rats received aflatoxins for 15 days and aqueous extract of the green tea for 30 days, group 4 (green tea aqueous extract group) and group 5(control negative group). Detailed non-traditional histological and morphometrical analyses for renal tissues stained with Hematoxylin and Eosin, Masson's trichrome stain, Periodic Acid Schiff’s (PAS), Alizarin red S stains and immunohistochemical detection of Ki-67 were done. The main observed renal lesions in rats received aflatoxins were dilatation of the renal pelvis, increases in glomerular areas (GA), widening of Bowman's spaces and necrosis of the renal lining epithelium and proliferation of fibrous connective tissues. Morphometric analysis revealed the presence of significant difference between group I and the other experimental groups. Meanwhile, groups 2 and 3 revealed a significant improvement in the histological changes and decrease in most of parameters. The highest percentage of PAS positive reaction was significantly found in group 4. Quantitative analysis of positive reactions of Ki-67 revealed the highest positive immunohistochemical reactions were detected in group 1 which significantly different in groups 4 and 5. In conclusion, green tea has a protective effect against the adverse effects of aflatoxins on renal tissues evidenced by improvement of histopathological alterations and regulation of Ki-67 expressions.

Application of betaine as feed additives in poultry nutrition – a review

Heat stress is exposing birds to degrees of temperature higher than the optimal, which results in numerous health problems i.e. respiratory deficits decrease feed intake and thus lower weight at marketing age. Heat stress represents one of the most important factor that has negative effects on poultry production. Heat stress also leads to negative effects on the carcass properties and thus lower meat quality, consequently leads to severe shortage in the market. Most important solutions are using feed additives that have positive effects for resisting thermal stress. Betaine that has several other beneficial effects of mild heat stress. Most of the trials were reported slight positive effects; however, systematic results were rare. Since there are almost unlimited possibilities concerning dosage and products of betaine there is still more research required. Nevertheless, there is still further research under more standardized conditions needed to evaluate the right dosage and combination as well as the exact mechanism of actions of anti-stress effects of betaine.