Ligation In Rats Research Articles

The lesion of dorsolateral funiculus changes the antiallodynic effect of the intrathecal muscimol and baclofen in distinct phases of neuropathic pain induced by spinal nerve ligation in rats.

The abnormal firing of damaged primary afferents and the changes in the central nervous system (CNS) play important role in the initiation and maintenance phases of neuropathic pain. These phases of neuropathic pain involve changes in the GABAergic control of descending pathways that travel through the dorsolateral funiculus (DLF). The present study shows that unilateral DLF lesion increased the antiallodynic effect of muscimol (0.2μg/5μL) (a GABAA receptor agonist) in the initiation, but not maintenance phase of the mechanical allodynia induced by a spinal nerve ligation (SNL) of the ipsilateral hindpaw of rats. The unilateral DLF lesion increased the antiallodynic effect of baclofen (0.8μg/5μL) (a GABAB receptor agonist) in the initiation phase and reduced your effect in the maintenance phase of the mechanical allodynia induced by a spinal nerve ligation (SNL) of the ipsilateral paw of rats. The unilateral DLF lesion significantly reduced the proallodynic effect of an intrathecal injection of phaclofen (30μg/5μL) (a GABAB receptor antagonist), but not bicuculline (0.3μg/5μL) (a GABAA receptor antagonist). The effect of DLF lesion on the proallodynic effect of phaclofen was observed in the maintenance, but not in the initiation phase of the mechanical allodynia induced by SNL. We than conclude that the spinal GABAergic neurotransmission is negatively modulated by DLF using GABAA and GABAB receptors, in the initiation phase of mechanical allodynia induced by SNL. In addition, the integrity of DLF is necessary for the effectiveness of GABAergic transmission that occurs via spinal GABAB, but not GABAA receptors, in the maintenance phase of mechanical allodynia induced by SNL.

Enhanced expression of renal AQP2 and ENaC in rats with chronic heart failure: a role for renal nerves

Previously we have shown that increased expression of renal epithelial sodium channels (ENaC) subunits may contribute to the renal sodium and water retention observed during chronic heart failure (CHF). The goal of this study was to examine whether renal denervation (RDN) changes the expression of aquaporin 2 (AQP2) and two major renal sodium transporters ENaC and sodium‐hydrogen exchanger‐3 proteins (NHE3)] in rats with CHF. CHF was produced by left coronary artery ligation in rats. Four weeks after ligation surgery, bilateral RDN were performed. Western blot analysis indicated that RDN (one week later) significantly reduced enhanced protein levels of AQP2 (1.30±0.20 vs. 0.33±0.09, P<0.05), alpha‐ENaC (0.43±0.09 vs. 0.25±0.06, P<0.05), beta‐ENaC (0.11±0.03 vs. 0.05 ± 0.01, P<0.05) and gamma‐ENaC (0.89±0.15 vs. 0.44±0.09, P<0.05) subunits in the renal cortex of CHF rats compared to the CHF non‐denervated group. RDN had no significant effects on the protein expression of kidney NHE3 in both sham and CHF rats. These findings suggest a critical role for renal nerves in the enhanced expression of AQP2 and ENaC and subsequent pathophysiology of renal water and sodium retention associated with CHF.Support or Funding InformationSupported by NIH grants HL124104 and HL62222

Senegenin Ameliorate Acute Lung Injury Through Reduction of Oxidative Stress and Inhibition of Inflammation in Cecal Ligation and Puncture-Induced Sepsis Rats.

The purpose of this study was to assess the protective effect of senegenin on acute lung injury (ALI) in rats induced by sepsis. Rat ALI model was reproduced by cecal ligation and puncture (CLP). All rats were randomly divided into five groups: group 1 (control), group 2 (CLP), group 3 (CLP + senegenin 15mg/kg), group 4 (CLP + senegenin 30mg/kg), and group 5 (CLP + senegenin 60mg/kg). CLP + senegenin groups received senegenin by gavage daily for consecutive 5days, respectively, while the mice in control and CLP groups were given an equivalent volume of saline. We detected the lung wet/dry weight ratios and the histopathology of the lung. The levels of lung tissue myeloperoxidase (MPO), malondialdehyde (MDA), superoxide dismutase (SOD), and glutathione (GSH) were determined. Meanwhile, the nuclear factor-kappa B (NF-κB) activation, tumor necrosis factor-alpha (TNF-α), and interleukin-1β (IL-1β) levels were studied. The results demonstrated that senegenin treatment significantly attenuated CLP-induced lung injury, including reduction of lung wet/dry weight ratio, protein leak, infiltration of leukocytes, and MPO activity. In addition, senegenin markedly decreased MDA content and increased SOD activity and GSH level. Serum levels of TNF-α and IL-1β were also decreased by senegenin administration. Furthermore, senegenin administration inhibited the nuclear translocation of NF-κB in the lungs. These findings indicate that senegenin exerts protective effects on CLP-induced septic rats. Senegenin may be a potential therapeutic agent against sepsis.

DONEPEZIL HYDROCHLORIDE MITIGATES CONSEQUENCES OF ACUTE MYOCARDIAL INFARCTION IN MALE ALBINO RATS

Background Cholinesterase inhibitors are used for symptomatic treatment of mild to moderate Alzheimer’s disease. These drugs have vagomimetic and anti-inflammatory properties that could be of interest also with respect to cardiovascular diseases. Aim The aim of the present work is to assess effects of pretreatment with donepezil hydrochloride, one of cholinesterase inhibitors, on acute myocardial infarction induced by coronary artery ligation in rats. Methods Rats were randomly divided into control, sham-operated, untreated-myocardial infarction, and donepezil hydrochloride-pretreated myocardial infarction groups. Donepezil hydrochloride was administered orally, 1mg/kg/day, for six days then acute myocardial infarction was induced in 6th day by ligation of the left anterior descending coronary artery. ECG and blood pressure were recorded. Triphenyltetrazolium chloride (TTC) stained ventricular slices were examined. The plasma levels of tumor necrosis factor-α (TNF-α) and cardiac troponin I (cTnI) were assessed. Catalase activity and glutathione levels in the myocardium were determined. Results Coronary artery ligation increased T-wave voltage with appearance of pathological Q-wave, tachycardia, decreased mean arterial pressure and pale areas (infarcts) in TTC-stained ventricular slices. The plasma levels of TNF-α and cTnI were increased while the myocardial catalase activity and glutathione levels were decreased. In donepezil hydrochloride-pretreated group T-wave voltage and heart rate were decreased and pathological Q-wave disappeared with decrements in infarct size and plasma levels of TNF-α as well as cTnI, while catalase activity and glutathione levels were increased in relation to untreated myocardial infarction group. Conclusion Pretreatment with donepezil hydrochloride decreased myocardial infarct size. This effect could be related to its negative chronotropic, anti-inflammatory, and antioxidant actions.

Elevation of Microglial Basic Fibroblast Growth Factor Contributes to Development of Neuropathic Pain after Spinal Nerve Ligation in Rats.

Reverse transcriptase-polymerase chain reaction (RT-PCR) and immunohistological analysis of spinal cord and pain behavior analysis in a rat neuropathic pain model were conducted to examine the function of microglial basic fibroblast growth factor (bFGF) in the development of neuropathic pain. To investigate the role of bFGF in spinal microglia during the development of allodynia following spinal nerve ligation in rats. Evidence suggests that the production of bFGF by spinal cord glial cells is increased in response to peripheral nerve injury. Although an association between bFGF and astrocytes has been widely reported, the relationship between bFGF and microglia, particularly with respect to the development of neuropathic pain, remains poorly understood. Spinal nerve ligation rats were used. After surgery, bFGF expression in the spinal cord was investigated using RT-PCR and immunohistochemistry. Neutralizing antibodies to bFGF were injected intrathecally into rats after spinal nerve ligaton. Spinal cords were used for RT-PCR analysis and pain behavior was analyzed using the von Frey test. bFGF mRNA expression was significantly increased in the spinal cord 6 hours after spinal nerve ligation compared with untreated rats. Immunohistochemical analysis revealed that bFGF co-localized with ionized calcium-binding adaptor molecule 1, a microglial marker, and myeloperoxidase. Neutralizing antibodies to bFGF attenuated mechanical allodynia and myeloperoxidase mRNA expression. bFGF increased in spinal microglia during the development allodynia after spinal nerve ligation. Thus, controlling bFGF release from microglia during the acute stage of peripheral nerve injury may suppress the progression of allodynia. N/A.

64Cu-DOTA as a surrogate positron analog of Gd-DOTA for cardiac fibrosis detection with PET: pharmacokinetic study in a rat model of chronic MI.

The aim of this study was to investigate the pharmacokinetics of (64)Cu-DOTA (1,4,7,10-azacyclododecane-N,N',N'',N'''-tetraacetic acid), a positron surrogate analog of the late gadolinium (Gd)-enhancement cardiac magnetic resonance agent, Gd-DOTA, in a rat model of chronic myocardial infarction (MI) and its microdistribution in the cardiac fibrosis by autoradiography. DOTA was labeled with (64)Cu-acetate. CD rats (n=5) with MI by left anterior descending coronary artery ligation and normal rats (n=6) were injected intravenously with (64)Cu-DOTA (18.5 MBq, 0.02 mmol DOTA/kg). Dynamic PET imaging was performed for 60 min after injection. (18)F-Fluorodeoxyglucose ([(18)F]-FDG) PET imaging was performed to identify the viable myocardium. For the region of interest analysis, the (64)Cu-DOTA PET image was coregistered to the [(18)F]-FDG PET image. To validate the PET images, slices of heart samples from the base to the apex were analyzed using autoradiography and by histological staining with Masson's trichrome. (64)Cu-DOTA was rapidly taken up in the infarct area. The time-activity curves demonstrated that (64)Cu-DOTA concentrations in the blood, fibrotic tissue, and perfusion-rich organs peaked within a minute post injection; thereafter, it was rapidly washed out in parallel with blood clearance and excreted through the renal system. The blood clearance curve was biphasic, with a distribution half-life of less than 3 min and an elimination half-life of ∼21.8 min. The elimination half-life of (64)Cu-DOTA from the focal fibrotic tissue (∼22.4 min) and the remote myocardium (∼20.1 min) was similar to the blood elimination half-life. Consequently, the uptake ratios of focal fibrosis-to-blood and remote myocardium-to-blood remained stable for the time period between 10 and 60 min. The corresponding ratios obtained from images acquired from 30 to 60 min were 1.09 and 0.59, respectively, indicating that the concentration of (64)Cu-DOTA in the focal fibrosis was 1.85 (1.09/0.59) times greater than that in the remote myocardium. Thus, this finding indicates that the extracellular volume fraction was 1.85 times greater in the focal fibrosis than in the remote myocardium. The accumulation of (64)Cu-DOTA in fibrotic tissue was further supported by autoradiography and histology images. The autoradiography images of (64)Cu-DOTA in the fibrotic tissues were qualitatively superimposed over the histology images of the fibrotic tissues. The histology images of the infarct areas were characterized by a heterogeneous distribution of thin bands of fibrotic collagen, myocytes, and expanded extracellular space. (64)Cu-DOTA is a useful surrogate positron analog of Gd-DOTA, enabling quantitative measurement of the uptake values in fibrotic tissues by dynamic PET imaging and calculation of the extracellular volume fractions of the fibrotic tissues. At a microscopic level, the distribution of (64)Cu-DOTA is nonuniform, corresponding to the heterogeneous distribution of expanded extracellular space in the setting of MI.

Bone marrow-derived mesenchymal stem cells effectively regenerate fibrotic liver in bile duct ligation rat model.

Mesenchymal stem cells (MSCs) have attracted lots of attention for the treatment of acute liver failure and end-stage liver diseases. This study aimed at investigating the fundamental mechanism by which bone marrow-derived MSCs (BM-MSCs) induce liver regeneration of fibrotic liver in rats. Rats underwent bile duct ligation (BDL) surgery and four weeks later they were treated with either BM-MSCs (3 × 10(6) cells /rat, once, tail vein injection) or silymarin (100 mg/kg, daily, orally) for four weeks. Liver function tests and hepatic oxidative stress were determined. Hepatic injury and fibrosis were assessed by H and E, Sirus red staining and immunohistochemical expression of α-smooth muscle actin (α-SMA). Hepatocyte growth factor (HGF) and the gene expression of cytokeratin-19 (CK-19) and matrix metalloproteinase-2 (MMP-2) in liver tissue were determined. BDL induced cholestatic liver injury characterized by elevated ALT and AST activities, bilirubin and decreased albumin. The architecture damage was staged as Metavir score: F3, A3. Fibrosis increased around proliferating bile duct as indicated by sirus red staining and α-SMA immunostaining. Fibrogenesis was favored over fibrolysis and confirmed by decreased HGF with increased expression of CK-19, but decreased MMP-2 expression. BM-MSCs treatment restored deteriorated liver functions and restored the histological changes, resolved fibrosis by improving liver regenerative capabilities (P < 0.001), increases in HGF and MMP-2 mRNA and downregulating CK-19 mRNA. Sliymarin, however, induced similar but less prominent effects compared to BM-MSCs. In conclusion, liver regenerative capabilities can be stimulated by BM-MSCs via augmentation of HGF that subsequently up-regulate MMP-2 mRNA while downregulating CK-19 mRNA.

Assessment of Vascular Geometry for Bilateral Carotid Artery Ligation to Induce Early Basilar Terminus Aneurysmal Remodeling in Rats.

Bilateral common carotid artery (CCA) ligation in rabbits is a model for basilar terminus (BT) aneurysm formation. We asked if this model could be replicated in rats. Fourteen female Sprague Dawley rats underwent bilateral CCA ligation (n=8) or sham surgery (n=6). After 7 days, 5 ligated and 3 sham rats were euthanized for histological evaluation of BT aneurysm formation, while the remaining rats were imaged with magnetic resonance angiography, euthanized, and subjected to corrosion casting of the Circle of Willis (CoW). 3D micro computed tomography images of CoW casts were used for flow simulations at the rat BT, and electron micrographs of the casts were analyzed for aneurysmal and morphological changes. Results from these analyses were compared to rabbit model data (n=10 ligated and n=6 sham). Bilateral CCA ligation did not produce aneurysmal damage at the rat BT. While the surgical manipulation increased rat basilar artery flow, fluid dynamics simulations showed that the initial hemodynamic stress at the rat BT was significantly less than in rabbits. Rats also exhibited fewer morphological and pathological changes (minor changes only occurred in the posterior CoW) than rabbits, which had drastic changes throughout the CoW. A comparison of CoW anatomies demonstrated a greater number of branching arteries at the BT, larger CoW arteries in relation to basilar artery, and a steeper BT bifurcation angle in the rat. These differences could account for the lower hemodynamic stress at the BT and in the cerebrovasculature of the rat. In conclusion, bilateral CCA ligation in rats does not recapitulate the rabbit model of early flow-induced BT aneurysm. We suspect that the different CoW morphology of the rat lessens hemodynamic insults, thereby diminishing flow-induced aneurysmal remodeling.

Caveolin-1 is upregulated in hepatic stellate cells but not sinusoidal endothelial cells after liver injury.

Sinusoidal endothelial cells (SEC) and hepatic stellate cells (HSC) are closely associated specialized vascular cells residing in the hepatic sinusoid. These cells have been shown to play important roles in many different pathophysiologic processes, in particular in liver fibrosis/cirrhosis and portal hypertension. Caveolin-1 functions as a scaffolding protein, and has a variety of functions including in many disease states, such as liver cirrhosis. Although previous studies have shown that in the injured rat liver, caveolin-1 is upregulated, the precise cells in which remains unclear. Therefore, the purpose of this study was to clarify the cell type (or types) in which caveolin-1 is expressed in normal and injured rat liver. We have utilized both detailed immunohistochemical labeling with cell specific markers as well as cell isolation techniques (isolating sinusoidal endothelial cells, HSCs, and hepatocytes) in normal and injured (bile duct ligation) rat liver. We show here that in the normal liver caveolin-1 is expressed predominantly in HSCs and SECs but after liver injury there is upregulation of caveolin-1 in HSCs, but not in SECs. These data have functional implications for the cells in which caveolin-1 is regulated.

A Study of Myocardial Ischemia Model Induced by Left Coronary Artery Ligation in Rats

Objective: Coronary artery was ligated to study the characteristics of myocardial ischemia in rats. Methods: The left anterior descending artery was ligated to establish the rat model of acute myocardial ischemia. All animals were divided into normal control group, sham operation group and model group. 1, 2 and 4 weeks after modeling, ECG (II lead) was recorded, the weight of whole heart and left ventricle were recorded and organ indexes were calculated; myocardial infarct size was determined by TTC; CK, CK-MB, LDH, AST contents of serum were detected; cardiac function was determined by left ventricular intubation via carotid artery and left ventricular was taken to perform pathological observation. Results: 1 week after modeling, compared with the sham operation group, the ECG and heart function index of rats model had significant change, but the myocardial enzymes did not change significantly; 4 weeks after modeling, the ECG and cardiac function of animal models had a recovery trend, but the myocardial enzymes, including CK, CK-MB, LDH, AST, were significantly increased; 1 week after modeling, the left ventricular indexes of model rats were increased; the infarct size was about 30%, myocardial cell necrosis and granulation tissue hyperplasia could be observed in infarction area; with the modeling time extended, from 2 to 4 weeks, the left ventricular and heart indexes of model group were significantly increased; the infarct size was relatively constant, left ventricular became thickly, and fibrous or granulation tissue was significantly proliferated in infarction area under microscope. Conclusion: The indexes of myocardial ischemia induced by coronary artery ligation in rats are different at different time points. The results suggest that the time point should be selected to observe the anti-myocardial ischemia effect of the subjects from different aspects.

Ulcer Protective Activity of Jatropha gossypiifolia Linn. in Wistar Rats.

Background:Several synthetic drugs are useful in the treatment of peptic ulcer, but almost of these drugs are used in prolonging time, it may cause several adverse reactions. However, the herbal medicines are more potent to the treatment and minimize the side effects.Objective:To evaluate the methanol extract of Jatropha gossypiifolia Linn. (MEJG) for gastro protective activity against Wistar rats.Materials and Methods:Anti-ulcer potency of MEJG (100 and 200 mg/kg, b.w.) was assessed using aspirin (200 mg/kg, p.o.) plus pylorus ligation ulcer model and the parameters studied were ulcer index (UI), gastric juice volume, pH, total acidity, and total acid output. Same extract was studied by ethanol-induced (80%, 5 mL/kg, intragastrically) ulcer model, and the UI and biochemical parameters were studied.Results:The oral administration of MEJG (100 and 200 mg/kg) significantly (P < 0.001) attenuated the ulcer score and anti-secretary parameters (such as the volume of gastric content, free acidity, total acidity, and total acid output) in the aspirin plus pylorus ligation rats. The extract also significantly attenuated (P < 0.001) ulcer score in ethanol-induced ulcer model and lipid peroxidation level and significantly increased the level of glutathione peroxides, catalase, and superoxide dismutase activity. The MEJG may possess active constituents such as alkaloids, glycosides, flavonoids, and terpenes, which may play a major role in gastroprotective effect in Wistar rats.Conclusion:The present study provides scientific support for the anti-ulcer activities of extracts of JG and also claimed that antioxidant potential of the extracts. However, substantiates the traditional claims for the usage of this drug in the treatment of gastric ulcer.SUMMARY The methanolic extract of jatropha gossypiifolia Linn. for gastro protective activity against aspirin plus pyloric ligation and ethanol induced ulcer models was studied in Wistar rats. JG shows significantly attenuated the ulcer score in both models. And also attenuated in anti-secretory parameters in aspirin induced ulcer model. MEJG may possess active constituents such as alkaloids, glycosides, flavonoids and terpenes, which may play a major role in gastroprotective effect in Wistar rats. Abbreviation Used: MEJG: Methanolic extract of jatropha gossypiifolia, mg: Milli gram, kg: Kilogram, b.w.: Body weight, p.o.: Per oral, UI: Ulcer index, pH: Concentration of H+ ion, mL: Milli litre, JG: Jatropha gossypiifolia,USD: United States Dollar, NSAIDs: Non steroidal anti-inflammatory drugs, v/v: Volume by volume, w/v: Weight by volume, SCMC: Sodium carboxy methyl cellulose, g: Gram, h: Hour, °C: Degree centigrade, n: Number, Rpm: Rotation per minute, Min: Minute, N: Normality, NaoH: Sodium hydroxide, mM - Millimole, TBA: Thiobarbituric acid, nmol: Nanomole, nm: Nanometer, GPx: Glutathione peroxidase, GSH: Reduced glutathione, H2O2: Hydrogen peroxide, SOD: Superoxide dismutase, ANOVA: Analysis of Variance, μmol: Micromole

Enhanced RAGE Expression in the Dorsal Root Ganglion May Contribute to Neuropathic Pain Induced by Spinal Nerve Ligation in Rats.

There is some evidence implicating receptor for advanced glycation end products (RAGE) signaling in the pathogenesis of neuropathic pain (NP). The objective was to investigate whether RAGE signaling in the dorsal root ganglion (DRG) might contribute to NP following peripheral nerve injury. Experimental study before and after spinal nerve ligation (SNL) surgery. Caged in a controlled environment. Male Sprague-Dawley rats. A SNL rat model of NP was used. Mechanical hyperalgesia was measured by the paw withdrawal threshold (PWT) to mechanical stimuli (1.4-15 g). Protein expressions of RAGE (immunofluorescence and western blotting), glial fibrillary acidic protein (GFAP; satellite glial cell [SGC] activation marker), IL-1β (ELISA), TNF-α (ELISA), and NF-κB (western blotting) in the DRG were determined. RAGE signaling was inhibited by intrathecal injection of anti-RAGE antibody. After 7 days, SNL surgery reduced the PWT and upregulated the protein expression of RAGE, GFAP, NF-κB, TNF-α, and IL-1β. Intrathecal injection of RAGE-neutralizing antibody attenuated the SNL-induced mechanical hyperalgesia, activation of SGCs, and upregulation of NF-κB, TNF-α, and IL-1β in the DRG. RAGE signaling may contribute to the pain hypersensitivity observed in the rat SNL model of NP. Although the precise mechanism remains to be established, NF-κB, TNF-α, and IL-1β likely play a role, together with the activation of SGCs.

Urinary Proteolytic Activation of Renal Epithelial Na + Channels in Chronic Heart Failure

One of the key mechanisms involved in renal Na(+) retention in chronic heart failure (CHF) is activation of epithelial Na(+) channels (ENaC) in collecting tubules. Proteolytic cleavage has an important role in activating ENaC. We hypothesized that enhanced levels of proteases in renal tubular fluid activate ENaC, resulting in renal Na(+) retention in rats with CHF. CHF was produced by left coronary artery ligation in rats. By immunoblotting, we found that several urinary serine proteases were significantly increased in CHF rats compared with sham rats (fold increases: furin 6.7, prostasin 23.6, plasminogen 2.06, and plasmin 3.57 versus sham). Similar increases were observed in urinary samples from patients with CHF. Whole-cell patch clamp was conducted in cultured renal collecting duct M-1 cells to record Na(+) currents. Protease-rich urine (from rats and patients with CHF) significantly increased the Na(+) inward current in M-1 cells. Two weeks of protease inhibitor treatment significantly abrogated the enhanced diuretic and natriuretic responses to ENaC inhibitor benzamil in rats with CHF. Increased podocyte lesions were observed in the kidneys of rats with CHF by transmission electron microscopy. Consistent with these results, podocyte damage markers desmin and podocin expressions were also increased in rats with CHF (increased ≈2-folds). These findings suggest that podocyte damage may lead to increased proteases in the tubular fluid, which in turn contributes to the enhanced renal ENaC activity, providing a novel mechanistic insight for Na(+) retention commonly observed in CHF.

Annexin A2 inhibits the migration of PASMCs stimulated with HPS rat serum by down-regulating the expression of paxillin

Hepatopulmonary syndrome (HPS) has been classically associated with intrapulmonary vasodilatation (IPVD) and pulmonary vascular remodelling (PVR), which are the key pathophysiological components of HPS and concerned frequently in the studies of HPS. Little is known about the relevance of pulmonary artery smooth muscle cells (PASMCs) migration or the molecular mechanisms of PVR in HPS. Annexin A2 (ANXA2) plays crucial role in HPS-associated PVR and might activate the activity of paxillin which as a regulatory protein participates in the regulation of PASMCs function in PVR. In addition, it has been identified that ANXA2 could influence the cells migration by some important signaling pathways in many diseases, including lung cancer, pulmonary hypertensionand and liver cancer. In this study, we performed scratch wound motility assay, modified boyden chamber, reverse transcription PCR, western blot and co-immunoprecipitation to determine the role of ANXA2 on HPS-associated PVR. We found that HPS rat serum from a common bile duct ligation (CBDL) rat model enhanced the migration of PASMCs and increased the expression of ANXA2 in PASMCs. We reported that ANXA2 and paxillin could form a co-immunoprecipitation. After silencing ANXA2 with siRNA, we found that the up-regulation of paxillin expression, induced by the HPS rat serum, was reversed. Additionally, we found that down-regulation of ANXA2 could significantly inhibit the migration of PASMCs. These findings indicated that down-regulation of ANXA2 by siRNA results in the inhibition of the aberrant dysregulation of paxillin and migration of PASMCs, which suggesting a potential therapeutic effect on HPS-associated PVR.

The Effect of Prunus cerasus (Sour Cherry) Kernel Seed Extract on QT Interval of Heart and its Histopathology in Biliary Cirrhosis Induced by Bile Duct Ligation in Rats

Background: QT prolongation is a problem that increases the ventricular arrhythmias in the cirrhotic patients. Sour cherry seed extract has been reported to have potential anti-inflammatory and antioxidant activity. Objectives: This study aimed to find the effect of Prunus cerasus (sour cherry) kernel seed extract on QT interval of heart and its histopathological parameters in rats with biliary cirrhosis induced by bile duct ligation (BDL). Materials and Methods: Thirty-two male Sprague Dawley rats (200 - 250 g) were divided into 4 groups; negative control, cirrhotic, and 2 cirrhotic groups treated with sour cherry kernel extract in doses of 10 mg/kg and 30 mg/kg orally for 4 weeks. In all groups before BDL and 4 weeks after surgery animals were anesthetized and their electrocardiograms were recorded. After the required period of BDL, liver was isolated and immersed in 10% formalin solution and stained by hematoxylin and eosin for histological studies. Results: Results were analyzed by using Student t-test and one-way ANOVA. P < 0.05 was considered as significant level. The QT interval was calculated using the Bazettʼs formula and corrected QT (QTc) was obtained. Four weeks after BDL, the QTc and amount of total and direct bilirubin in cirrhotic group were found as 213.6 ± 6.8 ms, 10.5 ± 1.02 mg/dL, and 7.9 ± 0.7 mg/dL, respectively. These values significantly increased compared to the negative control group (119.9 ± 6.2 ms, 0.11 ± 0.00102 mg/dL, and 0.1 ± 0.0002 mg/dL) (P < 0.001). Histopathological parameters were reduced in cirrhotic groups treated with extract compared to control cirrhotic group. Conclusions: These results revealed that cirrhosis produce prolonged QT interval and sour cherry extract has an ameliorating effect on QT prolongation probably via its antiarrhythmic property.

Antioxidant Effect of Sepia Ink Extract on Extrahepatic Cholestasis Induced by Bile Duct Ligation in Rats

ObjectiveThe aim of our study was to assess the complications of hepatic fibrosis associated with bile duct ligation and the potential curative role of sepia ink extract in hepatic damage induced by bile duct ligation. MethodsRattus norvegicus rats were divided into 3 groups: Sham-operated group, model rats that underwent common bile duct ligation (BDL), and BDL rats treated orally with sepia ink extract (200 mg/kg body weight) for 7, 14, and 28 d after BDL. ResultsThere was a significant reduction in hepatic enzymes, ALP, GGT, bilirubin levels, and oxidative stress in the BDL group after treatment with sepia ink extract. Collagen deposition reduced after sepia ink extract treatment as compared to BDL groups, suggesting that the liver was repaired. Histopathological examination of liver treated with sepia ink extract showed moderate degeneration in the hepatic architecture and mild degeneration in hepatocytes as compared to BDL groups. ConclusionSepia ink extract provides a curative effect and an antioxidant capacity on BDL rats and could ameliorate the complications of liver cholestasis.

Protective effect of gastrodin on bile duct ligation-induced hepatic fibrosis in rats

Gastrodin has been showed to possess many beneficial physiological functions, including protection against inflammation and oxidation and apoptosis. Studies showed inflammation and oxidation play important roles in producing liver damage and initiating hepatic fibrogenesis. However, it has not been reported whether gastrodin has a protective effect against hepatic fibrosis or not. This is first ever made attempts to test gastrodin against liver fibrosis in bile duct ligation (BDL) rats. The aim of the present study is to evaluate the effect of gastrodin on BDL-induced hepatic fibrosis in rats. BDL rats were divided into two groups, BDL alone group, and BDL-gastrodin group treated with gastrodin (5 mg/ml in drinking water). The effects of gastrodin on BDL-induced hepatic injury and fibrosis in rats were estimated by assessing serum, urine, bile and liver tissue biochemistry followed by liver histopathology (using hematoxylin & eosin and sirius red stain) and hydroxyproline content measurement. The results showed that gastrodin treatment significantly reduced collagen content, bile duct proliferation and parenchymal necrosis after BDL. The serum alanine aminotransferase (ALT) and serum aspartate aminotransferase (AST) decreased with gastrodin treatment by 15.1 and 23.6 percent respectively in comparison to BDL group did not receive gastrodin. Gastrodin also significantly increased the level of serum high density lipoprotein (HDL) by 62.5 percent and down-regulated the elevated urine total bilirubin (TBIL) by 56.5 percent, but had no effect on total bile acid (TBA) in serum, bile and liver tissues. The immunohistochemical assay showed gastrodin remarkably reduced the expressions of CD68 and NF-κB in BDL rats. Hepatic SOD levels, depressed by BDL, were also increased by gastrodin by 8.4 percent. In addition, the increases of hepatic MDA and NO levels in BDL rats were attenuated by gastrodin by 31.3 and 38.7 percent separately. Our results indicate that gastrodin significantly attenuated the severity of BDL-induced hepatic injury and fibrosis by attenuating oxidative stress and inflammation. Taken together, these findings suggest that gastrodin might be an effective antifibrotic drug in cholestatic liver disease.

Ischemia reperfusion of the hepatic artery induces the functional damage of large bile ducts by changes in the expression of angiogenic factors.

Liver transplantation and cholangiocarcinoma induce biliary dysfunction following ischemia reperfusion (IR). The function of the intrahepatic biliary tree is regulated by both autocrine and paracrine factors. The aim of the study was to demonstrate that IR-induced damage of cholangiocytes is associated with altered expression of biliary angiogenic factors. Normal and bile duct ligation rats underwent 24-h sham or hepatic reperfusion after 30 min of transient occlusion of the hepatic artery (HAIR) or portal vein (PVIR) before collecting liver blocks and cholangiocyte RNA or protein. We evaluated liver histology, biliary apoptosis, proliferation and expression of VEGF-A/C, VEGFR-2/3, Ang-1/2, and Tie-1/2 in liver sections and isolated small and large cholangiocytes. Normal rat intrahepatic cholangiocyte cultures (NRICC) were maintained under standard conditions in normoxic or under a hypoxic atmosphere for 4 h and then transferred to normal conditions for selected times. Subsequently, we measured changes in biliary proliferation and apoptosis and the expression of VEGF-A/C and VEGFR-2/3. In vivo, HAIR (but not PVIR) induced damage of large bile ducts and decreased proliferation and secretin-stimulated cAMP levels. HAIR-induced damage of large bile ducts was associated with increased expression of VEGF-A/C, VEGFR-2/3, Ang-1/2, and Tie-1/2. In vitro, under hypoxic conditions, there was increased apoptosis and reduced proliferation of NRICC concomitant with enhanced expression of VEGF-A/C and VEGFR-2/3. The functional damage of large bile ducts by HAIR and hypoxia is associated with increased expression of angiogenic factors in small cholangiocytes, presumably due to a compensatory mechanism in response to biliary damage.

Osteodystrophy in Cholestatic Liver Diseases Is Attenuated by Anti-γ-Glutamyl Transpeptidase Antibody.

BackgroundCholestatic liver diseases exhibit higher levels of serum γ-glutamyl transpeptidase (GGT) and incidence of secondary osteoporosis. GGT has been identified as a novel bone-resorbing factor that stimulates osteoclast formation. The aim of this study was to elucidate the interaction of elevated GGT levels and cholestatic liver disease-induced bone loss.MethodsWistar rats were divided into three groups: sham-operated control (SO) rats, bile duct ligation (BDL) rats, and anti-GGT antibody-treated BDL rats (AGT). Serum GGT level was measured. Bone mineral density (BMD) was analyzed by dual-energy X-ray absorptiometry. Bone morphometric parameters and microarchitectural properties were determined by micro-computed tomography and histomorphometry of the distal metaphysis of femurs. Alterations of bone metabolism-related factors were evaluated by cytokine array. Effects of GGT on osteoblasts or stromal cells were evaluated by RT-PCR, enzyme activity, and mineralization ability.ResultsSerum levels of GGT were significantly elevated in the BDL-group. In the BDL group, BMD, bone mass percentage, and osteoblast number were significantly decreased, whereas osteoclast number was significantly increased. These alterations were markedly attenuated in the AGT group. The mRNA levels of vascular endothelial growth factor-A, LPS-induced CXC chemokine, monocyte chemoattractant protein-1, tumor necrosis factor-α interleukin-1β and receptor activator of nuclear factor-kappa B ligand were upregulated, and those of interferon-γ and osteoprotegerin were downregulated in the GGT-treated stromal cells. Furthermore, GGT inhibited mineral nodule formation and expression of alkaline phosphatase and bone sialo-protein in osteoblastic cells.ConclusionOur results indicate that elevated GGT level is involved in hepatic osteodystrophy through secretion of bone resorbing factor from GGT-stimulated osteoblasts/bone marrow stromal cells. In addition, GGT also possesses suppressive effects on bone formation. Managing elevated GGT levels by anti-GGT antibody may become a novel therapeutic agent for hepatic osteodystrophy in chronic liver diseases.

Dexmedetomidine Attenuates Bilirubin-Induced Lung Alveolar Epithelial Cell Death In Vitro and In Vivo.

Objective:To investigate bilirubin-induced lung alveolar epithelial cell injury together with the protection afforded by dexmedetomidine.Design:Prospective, randomized, controlled study.Setting:Research laboratory.Subjects:Sprague Dawley rats.Interventions:Alveolar epithelial A549 cell lines were cultured and received bilirubin (from 0 to 160 μM) to explore the protective pathway of dexmedetomidine on bilirubin-induced alveolar epithelial cell injury assessed by immunochemistry and flow cytometry. Sprague-Dawley rats were subjected to common bile duct ligation surgery to explore the protective effect of dexmedetomidine on hyperbilirubinemia-induced alveolar epithelial cell injury and respiratory failure in comparison with the Sham (subjected to the surgery procedure but without bile duct ligation) or dexmedetomidine control (only received intraperitoneal injection of dexmedetomidine).Measurements and Main Results:In vitro, dexmedetomidine reversed the collapse of mitochondrial membrane potential (Δψm), upregulation of cytochrome C, B cell leukemia 2 associated X protein, and cleaved-caspase 3 and 9 in A549 epithelial cells with bilirubin challenge. Furthermore, dexmedetomidine reversed the arrest of cell cycle and the downregulation of the transforming growth factorβ, phosphorylated mammalian target of rapamycin, and p42/44 mitogen-activated protein kinase induced by bilirubin. In vivo, pulmonary edema and inflammation were found after common bile duct ligation. Bilirubin and Paco2 were significantly increased, and oxygen (Pao2) was significantly decreased in the blood of common bile duct ligation rats from the postsurgery day 7 to day 21 when compared with those in the sham controls, respectively (p < 0.01). Daily intraperitoneal injection of dexmedetomidine significantly alleviated the lung edema and injury and prevented respiratory failure.Conclusion:Our data both in vitro and in vivo demonstrated that dexmedetomidine protected alveolar epithelial cell from bilirubin-induced injury. Dexmedetomidine may be a good choice of anesthetic/sedative for patients with chronic liver disease during the perioperative period.