We investigated dose-related pathological alterations and apoptosis in rat kidney tissue exposed to permethrin. Histopathological findings, apoptotic cell death and urinary 3-phenoxybenzoic acid concentrations (3-PBA) were evaluated. Different doses of permethrin were administered to animals by oro-gastric gavage. A dose-dependent increase of urine 3-PBA concentration was observed in all the permethrin-treated groups. SDS-PAGE separated 30–45 kD and 100–220 kD protein bands in all experimental groups. Histopathologically, degenerative changes were observed in the epithelial lining of the S1, S2, and S3 segments of the renal proximal tubules. Apoptotic cells were seen in the inner stripe of the outer medulla in Group I, and both the cortex and medulla in Groups II and III. Immunohistochemical staining of caspase 3 and caspase 9 also was observed in the same areas. Our results suggest that damage to regions of the proximal tubules is dose-related, and caspase-9-dependent, mitochondria-related apoptotic cell death could play an important role in permethrin-induced nephrotoxicity. We also observed morphologically necrotic cells. We concluded that both necrosis and apoptosis are produced by permethrin.

Summary: The aim of this study was to evaluate dichlorvos toxicity in terms of nitro-oxidative stress by determining 3-nitrotyrosine (3-NT) levels in the fore, mid, and hindbrain regions in acutely exposed rats. Male Sprague- Dawley rats were randomly allocated to three groups of eight. Group 1 was administered a single intraperitoneal dichlorvos dose of 1.8 mg kg-1 (0.1xLD₅₀) and group 2 a dose of 9 mg kg-1 (0.5xLD₅₀). The control group received 0.5 mL saline solution via the same route. 3-NT and tyrosine (TYR) levels were measured using high performance liquid chromatography with a photodiode array detector (HPLC-PDA) and expressed as a ratio of 3-NT to TYR. The 3-NT/1000 TYR ratios increased significantly in the fore-, mid- and hindbrains of the exposed groups compared to control (p<0.01). In the forebrain, the increase was also significant between the treated groups. Our study has confirmed that acute exposure to dichlorvos leads to nitro-oxidative stress in the brain and that 3-NT may play a role in the mechanism of dichlorvos neurotoxicity.

If the respiratory nasal mucosa is damaged and the mucosa does not heal properly during nasal or paranasal sinus surgery, a revision surgery may be required. The aim of this study is to investigate the effects of oral propolis application on mucosal wound healing following endoscopic nasal surgery in a rabbit model. Twenty four New Zealand rabbits were randomly divided into three groups, namely the experimental group (EG), the control group (CG), and the negative control group (NCG). Mucosal resection was applied with 3-mm punch forceps in the bilateral ventral nasal concha in the experimental and control groups. 75 mg/kg/day propolis was added to the diet of the rabbits in the EG for 14 days. The CG continued with the standard diet postoperatively. In the NCG, no surgical intervention was made, and no dietary support was given. On postoperative day 14 all rabbits were sacrificed and left nasal specimens were examined histopathologically, hydroxyproline levels were measured in right nasal specimens. There were no statistically significant differences in hydroxyproline level, epithelial and subepithelial thickness, ciliary and goblet cell count, subepithelial fibrosis and collagen density between EG and CG. Neutrophil count was statistically significantly lower in EG, compared to CG (p=0.019, Tamhane test). Although there are many studies that show the positive effects of propolis on wound healing, such effect was not observed in this study. This study is deemed to constitute a unique experimental study that can be a resource for future similar studies to be performed with higher numbers of subjects and higher dosage of propolis.

In this study, the levels of a group of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) in the adipose tissue of women living in northern Turkey who gave birth by cesarean delivery were investigated.

Synthetic pyrethroids are a group of insecticides frequently used in public health and agriculture, and 3-PBA is a common metabolite of them. Although the liver is the primary organ responsible for metabolizing many compounds including pesticides, to the authors’ knowledge there have been no studies on the direct hepatotoxic effects of 3-PBA. Therefore, this study aimed to investigate the possible hepatotoxic effects of 3-PBA on a Human Hepatoma Cell Line (HepG2) and the underlying apoptotic mechanisms. Firstly, an LC₅₀ of 1041.242 µM was calculated for 3-PBA by using the WST-1 test with concentrations ranging between 1 µM and 10 mM. Following that, the HepG2 cells in the experimental group were exposed to 3 different concentrations of 3-PBA (1/5 LC₅₀, 1/10 LC₅₀ and 1/20 LC₅₀) for 24 hours. The apoptotic mechanism was evaluated by using flow cytometry, and immunofluorescence assays for Caspase 3 and Bcl-2. In the flow cytometry assay, the total number of apoptotic cells increased in a dose dependent manner (p < 0.05). In the immunofluorescence assay, the Caspase 3 protein showed strong immunoreactivity in the experimental groups, while the reaction to the Bcl-2 protein was minimal. These results demonstrated that 3-PBA has a significant hepatotoxic effect on HepG2 cells and induces apoptosis via the regulation of Caspase-3 and Bcl-2. Furthermore, our results could further the understanding of the fundamental molecular mechanisms of 3-PBA hepatotoxicity. More studies are needed to determine the effects of long-term exposure to 3-PBA and also the molecular mechanisms underlying hepatotoxicity.

Background: Essential oils exhibit several biological activities such as antimicrobial, antioxidant, proliferative, and anti-inflammatory. This study was aimed at investigating the antimicrobial effects and cytotoxic activities of niaouli, palmarosa, and clove essential oils. Methods: Content analyses of these essential oils were carried out by gas chromatography–mass spectrometry. The antibacterial activity was screened against methicillin-resistant S. aureus ATCC 43300, P. aeruginosa ATCC 27853, P. aeruginosa PAO1, S. aureus ATCC 25923, and 44 isolates (22 P. aeruginosa isolates, 4 S. aureus isolates, and 18 Staphylococcus spp. isolates) obtained from dogs with previous wound infections who were included in the current study. The antimicrobial effects of essential oils were investigated using disk diffusion and minimum inhibition/bactericidal concentration methods. Additionally, the antibiofilm, protease, elastase, and gelatinase activities of the essential oils were evaluated. Different concentrations of each essential oil ranging from 10 to 1000 µg/mL were also analyzed in terms of cell viability by WST-8 assay in primary canine fibroblast cells. Results: The fibroblast cell viabilities of palmarosa, niaouli, and clove oils at a 1000 µg/mL concentration were 75.4%, 96.39%, and 75.34%, respectively. All the EOs were found to have bactericidal effects with MBCs/MICs of 0.015 to 0.5 µL/mL against P. aeruginosa, Staphylococcus isolates (p < 0.001). Palmarosa was found to have the largest inhibition zone diameter (20.5 ± 6.6, 16.4 ± 2.3) compared to other essential oils in the disk diffusion test against Staphylococcus spp. and P. aeruginosa (p < 0.001). But none of the EOs reduced protease, elastase, and gelatinase activities, which are some of the virulence properties of the tested bacteria. Conclusions: These results showed that palmarosa, niaouli, and clove essential oils act as potential antibacterial agents for dogs against P. aeruginosa, methicillin-resistant S. aureus, and Staphylococcus spp., without damaging the skin.