Biotechnic & Histochemistry最新文献

Abdominal aortic aneurysm (AAA) is a vascular disease that involves aortic wall dilation. Cigarette smoking is an established risk factor and rupture, and nicotine may be a major contributor to the onset of AAA. In humans the condition is associated with stenosis of the vasa vasorum (VV), which may be caused by nicotine. In this study, we evaluated the effects of nicotine on VV pathology. After 4 weeks of nicotine administration to rats using an osmotic pump, the VV patency rate in the nicotine administration group was significantly lower than that in the control group. The levels of Ki-67, a cell proliferation marker, were significantly increased in the regions containing VV in the nicotine group, as were hypoxia inducible factor-α levels. Collagen levels around VV were significantly lower in the nicotine group than in the controls. Our data suggest that nicotine can cause VV stenosis by inducing abnormal proliferation of smooth muscle cells in the VV. The increased risk of AAA development due to cigarette smoking may be partially explained by nicotine-induced VV denaturation and collagen fiber degradation.

Anterior cruciate ligament injuries are frequent afflictions related to sports or physical trauma. Autograft reconstruction strategies cause secondary injury to the patient. One alternative, supported by clinical evidence, is porcine xenografts. For clinical use, xenografts must be conditioned to avoid immune rejection. The most widely accepted procedure is tissue decellularization. We analyzed three decellularization strategies: the application of the anionic detergent sodium dodecyl sulfate (SDS), sonication, and freezing and thawing cycles. The treated tissues were evaluated histologically using H&E, Masson's trichrome, Verhoeff-van Gieson staining, and DAPI for fluorescent staining of nuclei. Finally, collagen fiber preservation was evaluated by quantifying this protein by colorimetry. The most efficient decellularization techniques were sonication and SDS. Collagen fibers were preserved in all experimental conditions.

Doxorubicin (DOX)-induced cardiotoxicity is a well known clinical problem, and many investigations have been made of its possible amelioration. We have investigated whether diazoxide (DIA), an agonist at mitochondrial ATP-sensitive potassium channels (mitoK_ATP), could reverse DOX-induced apoptotic myocardial cell loss, in cultured rat cardiomyocytes. The role of certain proteins in this pathway was also studied. The rat cardiomyocyte cell line (H9c2) was treated with DOX, and also co-treated with DOX and DIA, for 24 h. Distribution of actin filaments, mitochondrial membrane potential, superoxide dismutase (SOD) activity, total oxidant and antioxidant status (TOS and TAS, respectively), and some protein expressions, were assessed. DOX significantly decreased SOD activity, increased ERK1/2 protein levels, and depolarised the mitochondrial membrane, while DIA co-treatment inhibited such changes. DIA co-treatment ameliorated DOX-induced cytoskeletal changes via F-actin distribution and mitoK_ATP structure. Co-treatment also decreased ERK1/2 and cytochrome c protein levels. Cardiomyocyte loss due to oxidative stress-mediated apoptosis is a key event in DOX-induced cytotoxicity. DIA had protective effects on DOX-induced cardiotoxicity, via mitoK_ATP integrity, especially with elevated SUR2A levels; but also by a cascade including SOD/AMPK/ERK1/2. Therefore, DIA may be considered a candidate agent for protecting cardiomyocytes against DOX chemotherapy.

The adipocyte-derived hormone, leptin, plays a key role in the maintenance of energy homeostasis. Leptin binds to the long form of its receptor, which is predominantly expressed in various hypothalamic regions, including the lateral hypothalamic area (LH) and supraoptic nucleus (SO). Several studies have suggested that leptin directly activates neuronal nitric oxide synthase, leading to increased nitric oxide production. We used histochemistry for nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d) as a marker for nitric oxide synthase activity and assessed the effect of leptin on nitrergic neurons in the LH and SO of rats. We found that intraperitoneal administration of leptin led to a significant increase in the number of NADPH-d-positive neurons in the LH and SO. In addition, the intensity (optical density) of NADPH-d staining in LH and SO neurons was significantly elevated in rats that received leptin compared with saline-treated rats. These findings suggest that nitrergic neurons in the LH and SO may be implicated in mediating the central effects of leptin.

Laminin receptor 1 (LAMR) may have a role in the progression of premalignant squamous epithelial lesions to cervical cancer. Therefore, we aimed to investigate the expression of laminin receptor 1 (LAMR) in normal, premalignant, and malignant tissues of the uterine cervix. Paraffin blocks of 129 specimens with the diagnoses of normal cervical tissue (n = 33), cervical intraepithelial neoplasia (CIN) 1 (n = 30), CIN 2 (n = 14), CIN 3 (n = 28), and squamous cell carcinoma (n = 24) were immunohistochemically stained with LAMR antibody and its expression percentage, pattern, and intensity in these tissues were assessed. Compared to the other groups, the nonstaining with LAMR was highest in low grade squamous intraepithelial lesion (LSIL) (p < 0.0001). LAMR expression, which was positive in less than 50% of cells with weak staining, increased significantly between normal cervical epithelium and high-grade squamous intraepithelial lesion (HSIL) or invasive carcinoma, as well as between LSIL and HSIL (p < 0.0001). Between LSIL and invasive carcinoma, a significant increment was also observed for weak staining in less than 50% of cells (p < 0.001). LAMR expression, which was positive in more than 50% of cells with strong staining, was significantly higher in normal cervical tissue compared to the other groups (p < 0.0001). Disease progression related gradual increment of LAMR expression from normal cervical epithelium or LSIL towards HSIL or cervical cancer reveals that LAMR may play an important role in the transition from premalignant to malignant state in cervical lesions.

Myoglobinuric acute renal failure (MARF) is a structural and functional disorder that occurs in the kidney following the release of muscle cell contents into the circulation. In this present study, possible protective and curative effects of Ferula elaeochytris extract against kidney and liver damage in experimentally induced MARF in a rat model were investigated. 3-4 Month-old, 200-250 g Sprague Dawley rats were divided into 8 equal groups with 7 rats per group. Group I was a no-intervention Control group. All groups except for the Group I were dehydrated for 16 hours. Following this dehydration, 50% v/v aqueous glycerol solution was injected into both hind leg muscles of the animals, at a dose of 8 ml/kg. The rats were given physiological saline (SF) once orally before the model was administered (Group II) and after the model was administered (Group V). Similarly, two different doses of Ferula elaeochytris root extract (40 mg/kg and 80 mg/kg) were dissolved in 2 ml of SF and administered orally before (Groups III and IV) and after (Group VI, VII) the model was created. Following the experimental period, kidney and liver tissues were removed from all groups, and fixed in 10% neutral formaldehyde solution for light microscopic examinations. Intracellular vacuolization, enlargement in the Bowman's space, widespread atrophy in the tubular structures, luminal enlargement, and desquamation were detected in the kidney tissue sections of all the experimental model groups. In the liver tissue sections, was detected hepatocyte degeneration, intracellular vacuolization, irregularity in cell membrane borders, and apoptotic bodies. These histopathological consequences of MARF were evaluated for all groups, and whereas a curative effect of Ferula elaeochytris could be seen, its protective effect was higher than its curative effect.

We investigated the possible ameliorative effects of nobiletin (NBL) against methotrexate (MTX)-induced hepatorenal toxicity in rats. Twenty-eight Wistar albino rats were randomly divided into four groups, namely: Control; MTX (administered 20 mg/kg MTX); MTX+NBL (administered 20 mg/kg MTX and 10 mg/kg NBL per day); and NBL (administered 10 mg/kg/day NBL). Histopathological, immunohistochemical and biochemical analyses were performed on the kidney and liver tissues of rats at the end of the study. MTX caused renal toxicity, as indicated by increases in malondialdehyde (MDA) and caspase-3, as well as decreases in reduced glutathione (GSH), glucose-6-phosphate dehydrogenase (G6PD), glutathione peroxidase (GPx), catalase (CAT) and B-cell lymphoma-2 (Bcl-2). MTX also caused hepatotoxicity, as indicated by increases in 8-hydroxy-2'-deoxyguanosine (8-OHdG), tumor necrosis factor alpha (TNF-α), MDA and caspase-3 and decrease in interleukin 10 (IL-10), GSH, total antioxidant capacity, GPx, G6PD, CAT and Bcl-2. MTX caused histopathological changes in kidney and liver tissues indicating tissue and cellular damage. Administration of NBL concurrently with methotrexate reduced oxidative stress, inflammatory and apoptotic signs, and prevented kidney and liver damage caused by methotrexate. We consider NBL has attenuating and ameliorating effects on methotrexate-induced hepatorenal toxicity.