Pretreatment with pentoxifylline and N-acetylcysteine in liver ischemia reperfusion-induced renal injury

Renal protective potential of pentoxifylline, chlorpromazine, and lovastatin in ischemia-reperfusion injury: An experimental study

This study aimed to evaluate the ability of pentoxifylline when compared to lovastatin and chlorpromazine as nephroprotective substances in cases of renal ischemia and reperfusion syndrome (IRI). A total of 36 adult male animals were randomly allocated into four groups (untreated control group, pentoxifylline group, lovastatin group, and chlorpromazine group), each consisting of nine animals. All groups were submitted to experimental ischemia and reperfusion procedures. The animals were evaluated 24, 72 and 120 hours after IRI, including physical examinations, serum urea and creatinine measurements, as well as histopathological, morphometric, and stereological analyses of the renal tissue. Results indicated that 24 hours after IRI, only chlorpromazine was effective in controlling azotemia. At the 72-hour mark, both chlorpromazine and pentoxifylline exhibited efficacy. After 120 hours, all three substances demonstrated renal protective qualities. Pentoxifylline was the most effective in preserving the structural integrity of kidney tissue, followed by chlorpromazine. In conclusion, all three treatments (pentoxifylline, chlorpromazine, and lovastatin) were effective. Pentoxifylline proved to be promising in the response against acute tubular necrosis, although chlorpromazine presented earlier renoprotective effects in terms of maintaining renal function.

Pentoxifylline and thiamine ameliorate rhabdomyolysis-induced acute kidney injury in rats via suppressing TLR4/NF-κB and NLRP-3/caspase-1/gasdermin mediated-pyroptosis

Acute kidney injury (AKI) is a common complication of rhabdomyolysis (RM), a syndrome characterized by skeletal muscle damage resulting in renal tubular oxidative stress, inflammation, and activated toll like receptor-4 (TLR-4) and NOD-like receptor protein-3 (NLRP-3) inflammasome. Pyroptosis is a programmed cell death mediated by NLRP-3 leading to the activation of caspase-1 and gasdermin D (GSDMD), the hallmark of pyroptosis. This study aims to investigate the renoprotective effects of two antioxidants; pentoxifylline (PTX) and thiamine (TM) via targeting the aforementioned pathways. RM-AKI was induced in male Albino Wistar rats by intramuscular injection of glycerol (50% v/v, 10 ml/kg). PTX (100 mg/kg, oral) and TM (25 mg/kg, i.p) were administered for 12 days prior glycerol injection and continued for 3 days following induction of RM-AKI. Serum creatinine, blood urea nitrogen (BUN), creatin kinase, lipid peroxides, total antioxidant activity, inflammatory markers (tumor necrosis factor-α, interleukin-1β, and nuclear factor kappa B), TLR4, NLRP-3, caspase-1, GSDMD and c-myc (an apoptotic marker) were estimated. Compared to AKI model, co-administered drugs revealed a significant improvement in renal function and pathology as indicated by the reduction in serum creatinine, BUN and protein cast accumulation. The elevations of oxidative stress, and inflammatory markers as well as the over-expression of c-myc were alleviated. Protein levels of TLR4, NLRP3, cleaved caspase-1, and GSDMD were significantly elevated in RM-AKI model, and this elevation was attenuated by the tested drugs. In conclusion, PTX and TM could be a potential renoprotective approach for patients with RM through targeting TLR4/NF-κB and NLRP-3/caspase-1/gasdermin mediated-pyroptosis pathways.

A Renally Clearable Activatable Polymeric Nanoprobe for Early Detection of Hepatic Ischemia-Reperfusion Injury

Although hepatic ischemia-reperfusion injury (IRI) represents a major complication in many clinical settings, it remains a diagnostic dilemma due to its reliance on insensitive assays or invasive biopsy. The development of an activatable polymeric nanoprobe (APN_SO ) for real-time in vivo near-infrared fluorescence (NIRF) imaging and urinalysis of hepatic IRI is reported here. APN_SO has a backbone comprising renally clearable fluorophore fragments and self-immolative structural units. In the presence of an oxidative stress biomarker (superoxide anion, O₂ ^•- ) during hepatic IRI, APN_SO can be fluorescently activated for in vivo NIRF imaging and depolymerized to release renally clearable fluorophores for urinalysis. By virtue of its high hepatic accumulation, sensitive response toward O₂ ^•- , and effective release of renally clearable fluorophores, APN_SO -based imaging and urinalysis detect hepatic IRI at least 7 h earlier than typical clinical assays in a mouse model. This study not only provides new opportunities for noninvasive diagnosis of hepatic IRI, but also reveals guidelines for the development of optical nanosensors for early urinalysis.

Literature review of the mechanisms of acute kidney injury secondary to acute liver injury

People exposed to liver ischaemia reperfusion (IR) injury often develop acute kidney injury and the combination is associated with significant morbidity and mortality. Molecular mediators released by the liver in response to IR injury are the likely cause of acute kidney injury (AKI) in this setting, but the mediators have not yet been identified. Identifying the mechanism of injury will allow the identification of therapeutic targets which may modulate both liver IR injury and AKI following liver IR injury.

Prevention of the harmful effects of free oxygen radicals by using N-acetylcysteine in testicular torsion

INTRODUCTION

Testicular torsion is a urological emergency both in childhood and in adult life. Many studies on experimental testicular torsion have demonstrated biochemical and pathological ischemia-reperfusion injury and the efficacy of some drugs have been investigated to prevent this damage. N-acetylcysteine (NAC) promotes glutathione synthesis and acts as a glutathione precursor because of the fact that it increases the glutathione-reductase activity by transporting sulfhydryl groups.

AIM

In this experimental study, the authors aimed to investigate the effectiveness of NAC in preventing ischemia-reperfusion injury following testicular torsion and detorsion.

STUDY DESIGN

For this experimental study, 36 albino Wistar-male rats were used. The rats were randomly divided into 4 groups: sham (n = 8), ischemia-reperfusion (n = 8), ischemia-NAC -reperfusion (n = 10), and ischemia-NAC-reperfusion-NAC (n = 10) groups. Two hours of torsion and 4 h of detorsion were created in the left testis. After 4 h of detorsion, the rats were sacrificed. Each tissue was divided into two sections for biochemical and pathological examinations.

RESULTS

There was a statistically significant difference between the study groups in terms of the total-sulfhydryl level, nitric oxide level, and the malondialdehyde values. Histopathological examination revealed that NAC was effective in preventing reperfusion injury in the testis but ineffective in preventing the reduction in the spermatid count.

DISCUSSION

The results of this experimental study support that NAC can histopathologically maintain the structure of seminiferous tubules against ischemis reperfusion injury and prevent damage to the germinative cells. However, it was unable to prevent the reduction in spermatid count. There was no significant difference in the prevention of ischemia-reperfusion injury between NAC administration during the first hour of ischemia and NAC administration during reperfusion. Although NAC can prevent tissue damage from ischemia reperfusion injury, it is not effective against the reduction in the spermatid count.

CONCLUSION

N-acetylcysteine may be biochemically effective in preventing ischemia-reperfusion injury after testicular torsion and detorsion. NAC is a readily available and easy to use agent that can be used during testicular ischemia.

The possible structural changes in the adrenal gland cortex after induction of hepatic ischemia-reperfusion injury in male albino rats: Light and electron microscopic study

The adrenal gland is an important endocrine gland in the body that secrets the adrenal hormones. One of the important clinical issues is the hepatic ischemia-reperfusion (IR) injury. Liver IR injury results in many distant organs dysfunctions such as lung, kidney, intestine, pancreas, and myocardium. The aim of the present study was to investigate the possible remote effects of hepatic IR on the structure of the adrenal cortex. Twenty healthy males, Sprague-Dawley albino rats aged 6-8 weeks were randomly divided into two groups (10 rats each): the sham control group (SC-group) and the ischemia-reperfusion group (IR-group). Sera were estimated for the following: aspartate transaminase (AST), alanine transaminase (ALT), lactic dehydrogenase (LDH), and corticosterone levels. Also oxidative markers such as malondialdehyde (MDA) and tumor necrosis factor-α (TNF-α), and the antioxidative enzyme, catalase were measured. Adrenal glands were processed for light and transmission electron microscopic study. The results showed a significant increase in serum liver enzymes (AST, ALT, and LDH), corticosterone, MDA, and TNF-α levels and a significant decrease in serum levels of catalase in IR-group compared with SC-group. Adrenal cortical tissue of IR-group showed the loss of normal appearance. Some cells of zona glomerulosa and most of the zona fasciculata cells appeared swollen and degenerated with highly vacuolated cytoplasm. Other cells were shrunken with deeply acidophilic cytoplasm and pyknotic nuclei. Degenerated mitochondria with disrupted cristae, lipid droplets were confluent and dilated smooth endoplasmic reticulum were seen. Few zona reticularis cells had the dark nucleus and cytoplasmic vacuolations. In the different zones, blood capillaries were markedly congested and some inflammatory cells infiltrations were observed. Liver IR affected the structure of the adrenal cortex.

Pentoxifylline and Methylprednisolone Additively Alleviate Kidney Failure and Prolong Survival of Rats after Renal Warm Ischemia-Reperfusion

Renal ischemia-reperfusion injury (IRI) induces local inflammation leading to kidney damage. Since pentoxifylline (PTX) and steroids have distinct immunomodulatory properties, we aimed to evaluate for the first time their combined use in IRI-induced acute kidney injury (AKI) and chronic kidney disease (CKD) in rats. In two experiments, PTX (100 mg/kg body weight subcutaneously) was administered 90 min prior to renal IRI or/and methylprednisolone (MP; 100 mg/kg body weight intramuscularly) was infused 60 min after reperfusion of a solitary kidney (AKI model: 45 min ischemia, 48 male Sprague-Dawley rats) or one kidney with excision of contralateral kidney 2 weeks later (CKD model: 90 min ischemia, 38 rats). Saline was infused in place of PTX or/and MP depending on the group. Renal function (diuresis, serum creatinine, creatinine clearance, sodium and potassium excretion, and urine protein/creatinine) was assessed at 48 h and 120 h post-IRI (AKI model) or 4, 16 and 24 weeks after IRI, along with survival analysis (CKD model). More evidently at early stages of AKI or CKD, treated animals showed higher glomerular filtration and diminished tubular loss of electrolytes, more so with PTX + MP than PTX or MP (serum creatinine (μmol/L) at 48 h of AKI: 60.9 ± 19.1 vs. 131.1 ± 94.4 vs. 233.4 ± 137.0, respectively, vs. 451.5 ± 114.4 in controls, all p < 0.05; and at 4 weeks of CKD: 89.0 ± 31.9 vs. 118.1 ± 64.5 vs. 156.9 ± 72.6, respectively, vs. 222.9 ± 91.4 in controls, p < 0.05 for PTX or PTX + MP vs. controls and PTX + MP vs. MP). Survival was better by >2-fold with PTX + MP (89%) vs. controls (40%; p < 0.05). PTX + MP largely protect from IRI-induced AKI and CKD and subsequent mortality in rats. This calls for clinical investigations, especially in kidney transplantation.

Anesthetic Management for Prolonged Incidental Surgery in Advanced Liver Disease

In spite of advances in perioperative management, operative procedures in patients with chronic liver disease pose a significant challenge for the anesthesiologist due to multisystem involvement, high risk of postoperative hepatic decompensation, and mortality. We describe the anesthetic management of an elderly patient with advanced liver disease (model for end-stage liver disease 16) for prolonged abdominal surgery. The use of invasive hemodynamic monitoring, point-of-care biochemical, and hematological surveillance coupled with prompt correction of all abnormalities was responsible for good outcome. The patient's inguinal swellings turned out to be extensions of a large peritoneal mesothelioma, necessitating a large abdominal incision and blood loss. Analgesia was provided by bilateral transversus abdominis plane blocks, which helped to reduce opioid use and rapid extubation.

Hepatic ischemia/reperfusion injury associates with acute kidney injury in liver transplantation: Prospective cohort study

Solid clinical prospective studies investigating the association between hepatic ischemia/reperfusion injury (HIRI) and acute kidney injury (AKI) after liver transplantation are missing. HIRI, reflected by transaminase release, induces AKI in rodents, and retrospective studies suggest a similar association in humans. This prospective cohort study determined risk factors for AKI in 80 adult liver-only recipients. AKI defined by Risk, Injury, Failure, Loss, and End-Stage Kidney Disease (RIFLE) criteria developed in 21 (26%) recipients at 12 hours after reperfusion (interquartile range, 6 hours to postoperative day [POD] 1); 13 progressed from "risk" to "injury"; 5 progressed to "failure." In AKI patients, creatinine (Cr) increased during liver transplantation and was higher versus baseline at 6 hours to POD 4, whereas perioperative Cr remained stable in those without AKI. Plasma heart-type fatty acid-binding protein was higher 12 hours after reperfusion in AKI patients, though urinary kidney injury molecule 1 and neutrophil gelatinase-associated lipocalin were similar between those with or without AKI. Peak aspartate aminotransferase (AST), occurring at 6 hours, was the only independent risk factor for AKI (adjusted odds ratio, 2.42; 95% confidence interval, 1.24-4.91). Early allograft dysfunction occurred more frequently in AKI patients, and intensive care and hospital stays were longer. Patient survival at 1 year was 90% in those with AKI versus 98% in those without AKI. Chronic kidney disease stage ≥ 2 at 1 year was more frequent in patients who had had AKI (89% versus 58%, respectively). In conclusion, AKI is initiated early after liver reperfusion and its association with peak AST suggests HIRI as a determinant. Identifying operating mechanisms is critical to target interventions and to reduce associated morbidity. Liver Transplantation 23 634-644 2017 AASLD.

Protective effect of ursodeoxycholic acid, resveratrol, and N-acetylcysteine on nonalcoholic fatty liver disease in rats

CONTEXT

Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease. Resveratrol (RSV) and N-acetylcysteine (NAC) are safe representatives of natural and synthetic antioxidants, respectively.

OBJECTIVE

The objective of this study was to evaluate protective effects of RSV and NAC, compared with ursodeoxycholic acid (UDCA), on experimental NAFLD.

MATERIALS AND METHODS

NAFLD was induced by feeding rats a methionine choline-deficient diet (MCDD) for four cycles, each of 4 d of MCDD feeding and 3 d of fasting. Animals were divided into normal control, steatosis control, and five treatment groups, receiving UDCA (25 mg/kg/d), RSV (10 mg/kg/d), NAC (20 mg/kg/d), UDCA + RSV, and UDCA + NAC orally for 28 d. Liver integrity markers (liver index and serum transaminases), serum tumor necrosis factor-α (TNF-α), glucose, albumin, renal functions (urea, creatinine), lipid profile (total cholesterol; TC, triglycerides, high density lipoproteins, low density lipoproteins; LDL-C, very low density lipoproteins, leptin), and oxidative stress markers (hepatic malondialdehyde; MDA, glutathione; GSH, glutathione-S-transferase; GST) were measured using automatic analyzer, colorimetric kits, and ELISA kits, supported by a liver histopathological study.

RESULTS

RSV and NAC administration significantly improved liver index (RSV only), alanine transaminase (52, 52%), TNF-α (70, 70%), glucose (69, 80%), albumin (122, 114%), MDA (55, 63%), GSH (160, 152%), GST (84, 84%), TC (86, 86%), LDL-C (83, 81%), and leptin (59, 70%) levels compared with steatosis control values. A combination of RSV or NAC with UDCA seems to ameliorate their effects.

DISCUSSION AND CONCLUSION

RSV and NAC are effective on NAFLD through antioxidant, anti-inflammatory, and lipid-lowering potentials, where as RSV seems better than UDCA or NAC.

Pentoxifylline reduces the inflammatory process in diabetic rats: relationship with decreases of pro-inflammatory cytokines and inducible nitric oxide synthase

Studies suggest that inflammation is a key factor in the pathogenesis of diabetes mellitus. Pro-inflammatory cytokines, such as IL-6 and TNF-alpha, are produced by adipose tissue in large quantities, in obese and especially in diabetic individuals. Pentoxifylline (PTX) is a non-selective phosphodiesterase inhibitor with anti-inflammatory and antioxidant actions that may contribute to alleviate diabetes side effects, as neuropathy, retinopathy and nephropathy. This study aims to investigate PTX anti-inflammatory effects on the carrageenan-induced paw edema model, in alloxan-induced diabetic rats. Diabetic animals (male Wistar rats, 200–250 g) were daily treated with PTX (25, 50, 100 mg/kg, p.o.), glibenclamide (GLI, 5 mg/kg, p.o., as reference) or water, for 5 days. Afterwards, carrageenan-treated paws were dissected, their skin removed and the tissue used for preparation of homogenates and measurements of IL-6 and TNF-alpha by Elisa. Serum levels of nitrite were also determined and paw slices used for iNOS immunohistochemistry assays. We showed that diabetic rats presented an amplification of the inflammatory response, as related to non-diabetic rats, what was evident 48 h after the edema-induction. The PTX-treatment of diabetic rats reduced glycemia (as related to untreated-diabetic ones) and the paw edema. It also brought edema volumes to values similar to those of non-diabetic rats, at the same observation time. The increased TNF-alpha and IL-6 levels in paws of untreated-diabetic rats were reduced in diabetic animals after PTX treatments. Besides, the increased levels of nitrite in the serum of diabetic rats were also decreased by PTX. Furthermore, a higher number of iNOS immunostained cells was demonstrated in paw tissues from untreated-diabetic rats, as related to those of PTX-treated diabetic animals. Our results show that PTX reduces inflammatory parameters, as pro-inflammatory cytokines and iNOS expression, indicating the potential benefit of the drug for the treatment of diabetes and related pathologic conditions.

Pentoxifylline enhances the protective effects of hypertonic saline solution on liver ischemia reperfusion injury through inhibition of oxidative stress

BACKGROUND

Liver ischemia reperfusion (IR) injury triggers a systemic inflammatory response and is the main cause of organ dysfunction and adverse postoperative outcomes after liver surgery. Pentoxifylline (PTX) and hypertonic saline solution (HTS) have been identified to have beneficial effects against IR injury. This study aimed to investigate if the addition of PTX to HTS is superior to HTS alone for the prevention of liver IR injury.

METHODS

Male Wistar rats were allocated into three groups. Control rats underwent 60 minutes of partial liver ischemia, HTS rats were treated with 0.4 mL/kg of intravenous 7.5% NaCl 15 minutes before reperfusion, and HPTX group were treated with 7.5% NaCl plus 25 mg/kg of PTX 15 minutes before reperfusion. Samples were collected after reperfusion for determination of ALT, AST, TNF-alpha, IL-6, IL-10, mitochondrial respiration, lipid peroxidation, pulmonary permeability and myeloperoxidase.

RESULTS

HPTX significantly decreased TNF-alpha 30 minutes after reperfusion. HPTX and HTS significantly decreased ALT, AST, IL-6, mitochondrial dysfunction and pulmonary myeloperoxidase 4 hours after reperfusion. Compared with HTS only, HPTX significantly decreased hepatic oxidative stress 4 hours after reperfusion and pulmonary permeability 4 and 12 hours after reperfusion.

CONCLUSION

This study showed that PTX added the beneficial effects of HTS on liver IR injury through decreases of hepatic oxidative stress and pulmonary permeability.

N-acetylcysteine attenuates reactive-oxygen-species-mediated endoplasmic reticulum stress during liver ischemia-reperfusion injury

AIM: To investigate the effects of N-acetylcysteine (NAC) on endoplasmic reticulum (ER) stress and tissue injury during liver ischemia reperfusion injury (IRI).

METHODS: Mice were injected with NAC (300 mg/kg) intraperitoneally 2 h before ischemia. Real-time polymerase chain reaction and western blotting determined ER stress molecules (GRP78, ATF4 and CHOP). To analyze the role of NAC in reactive oxygen species (ROS)-mediated ER stress and apoptosis, lactate dehydrogenase (LDH) was examined in cultured hepatocytes treated by H₂O₂ or thapsigargin (TG).

RESULTS: NAC treatment significantly reduced the level of ROS and attenuated ROS-induced liver injury after IRI, based on glutathione, malondialdehyde, serum alanine aminotransferase levels, and histopathology. ROS-mediated ER stress was significantly inhibited in NAC-treated mice. In addition, NAC treatment significantly reduced caspase-3 activity and apoptosis after reperfusion, which correlated with the protein expression of Bcl-2 and Bcl-xl. Similarly, NAC treatment significantly inhibited LDH release from hepatocytes treated by H₂O₂ or TG.

CONCLUSION: This study provides new evidence for the protective effects of NAC treatment on hepatocytes during IRI. Through inhibition of ROS-mediated ER stress, NAC may be critical to inhibit the ER-stress-related apoptosis pathway.

Effects of dexpanthenol and N-acetylcysteine pretreatment in rats before renal ischemia/reperfusion injury

BACKGROUND

We investigated the anti-inflammatory and protective effects of concomitant use of dexpanthenol (DXP) and N-acetylcysteine (NAC) induced ischemia/reperfusion (I/R) injury of kidney.

METHODS

Forty rats were randomly divided into 5 groups. In all groups except for Group 1(Sham), renal arteries bilaterally occluded with vascular clamp for IR injury. Group 1(Sham), received a single dose of 10 mL/kg isotonic saline daily by intraperitoneal (IP) injection for three days. Group 2(IR), received a single dose of 10 mL/kg isotonic saline daily by IP injection for three days. Group 3(IR + NAC), received 300 mg/kg NAC daily by IP injection for three days. Group 4(IR + DXP), received 500 mg/kg DXP daily by IP injection for three days. Group 5(IR + NAC + DXP), received 500 mg/kg DXP and 300 mg/kg NAC daily by IP injection for three days. Serum urea (BUN), creatinine (Cr) and neutrophil gelatinase-associated lipocalin (NGAL, lipocalin 2, siderocalin) levels were measured as kidney function tests. TNF-α levels were measured as inflammatory marker. Tissue sections were evaluated histopathologically under light microscopy.

RESULTS

IR + NAC + DXP group received both NAC and DXP before induction of renal I/R and as the biochemical and histopathological data revealed the results of the IR + NAC + DXP group and sham group were similar. Biochemically and histopathologically, combined use of NAC and DXP has better results when each of them used alone.

CONCLUSION

We concluded that concomitant use of DXP and NAC plays a major role against I/R injury and may be useful in acute treatment of I/R induced renal failure.

The effect of pentoxifylline on penile cavernosal tissues in ischemic priapism-induced rat model

INTRODUCTION

Priapism is defined as persisting (>4 h), painful and abnormal tumescence that can occur without sexual stimulation. Three subtypes priapisms are seen-the non-ischemic priapism, intermittent and the ischemic priapism. In ischemic priapism, there is an abnormality in the veno-occlusive mechanism, resulting in venous stasis and accumulation of deoxygenated blood within the penile cavernosal tissue. Cavernosal tissue necrosis develops after extended period of ischemia and is eventually replaced by fibrotic tissue. It may results in erectile dysfunction if not treated promptly. Although, standard treatment of the ischemic priapism is penile aspiration and intracavernosal alpha-adrenergic agents, new oral agents have been investigated to reduce the cavernosal damage. In this study, the effect of different doses of pentoxifylline on cavernosal tissues was evaluated.

MATERIALS AND METHODS

Thirty-six male Wistar albino rats, age 5.5-6 months and weighing 250-300 g, were used in this study. The rats were randomly divided into five groups. In Group 1 (n = 7), the control group, only penectomy was performed. In Group 2 (n = 8), after 1 h of ischemic priapism, penectomy was performed. Group 3 (n = 7) received daily a 10 mg oral pentoxifylline for 4 weeks after 1 h of ischemic priapism, group 4 (n = 7) received a daily 30 mg oral pentoxifylline for 4 weeks after 1 h of ischemic priapism, and group 5 (n = 7) received a daily 100 mg oral pentoxifylline for 4 weeks after 1 h of ischemic priapism. At the completion of a 4-week period, penile tissues were obtained. Before penile tissues were obtained, intracavernosal pressures measured with electrical field stimulation and smooth muscle collagen ratio were evaluated pathologically.

RESULTS

Electrical field stimulation-induced intracavernosal relaxation decreased in group 2 compared with group 1 (p < 0.05). Electrical field stimulation-induced relaxation enhanced in the group 3, 4 and 5 compared to group 2 (p < 0.05). In group 2, the collagen density was significantly higher than group 1. Administration of pentoxifylline reduced the collagen density caused by ischemic priapism in groups 3, 4 and 5 compared with group 2.

CONCLUSION

The results of the present study showed that ischemic priapism caused damage in the penile tissues of rats, and treatment with pentoxifylline reduced the harmful effects of ischemic priapism.

Global consequences of liver ischemia/reperfusion injury

Liver ischemia/reperfusion injury has been extensively studied during the last decades and has been implicated in the pathophysiology of many clinical entities following hepatic surgery and transplantation. Apart from its pivotal role in the pathogenesis of the organ's post reperfusion injury, it has also been proposed as an underlying mechanism responsible for the dysfunction and injury of other organs as well. It seems that liver ischemia and reperfusion represent an event with “global” consequences that influence the function of many remote organs including the lung, kidney, intestine, pancreas, adrenals, and myocardium among others. The molecular and clinical manifestation of these remote organs injury may lead to the multiple organ dysfunction syndrome, frequently encountered in these patients. Remote organ injury seems to be in part the result of the oxidative burst and the inflammatory response following reperfusion. The present paper aims to review the existing literature regarding the proposed mechanisms of remote organ injury after liver ischemia and reperfusion.

Carboplatin-induced Fanconi-like syndrome in rats: amelioration by pentoxifylline

INTRODUCTION

Carboplatin is a congener of cisplatin used in the treatment of ovarian, head and neck and small-cell lung cancer. However, the clinical efficacy of carboplatin is marred by the development of ROS-dependent nephrotoxicity. The pathophysiological damage inflicted upon the kidney by carboplatin closely resembles to that of Fanconi syndrome.

AIMS AND OBJECTIVES

The present study aimed at inducing Fanconi-like syndrome in rats by administration of carboplatin. Objectives of the study involved evaluation of biochemical parameters coherent to Fanconi-like syndrome. Further, an attempt was made to evaluate the potential therapeutic effect of pentoxifylline in this condition.

RESULTS

The results of the study demonstrated that the urinary excretion profile of carboplatin treated rats closely resembled to that of patients suffering from Fanconi-like condition. Pentoxifylline was able to ameliorate this nephrotoxic condition as suggested by the change in levels of membrane bound ATPases, MDA and GSH. The urinary levels of tyrosine and cysteine correlate well with that of Fanconi-like condition in animals and humans.

CONCLUSION

In lieu of these observations, our study suggested that carboplatin-induced renovascular damage resembles to Fanconi-like condition which can be mitigated by pentoxifylline.

Pentoxifylline in liver ischemia and reperfusion

Pentoxifylline is a methylxanthine compound which was first filed in 1973 and registered in 1974 in the United States by Sanofi-Aventis Deustchland Gmbh for the treatment of intermittent claudication for chronic occlusive arterial disease. This methylxanthine was later discovered to be a phosphodiesterase inhibitor. Furthermore, its hemorheological properties and its function as an inhibitor of inflammatory cytokines, like TNF-α, allowed researchers to study its effects in organ ischemia and reperfusion and transplantation. Although this drug has demonstrated beneficial effects, the mechanisms by which Pentoxifylline exerts a protective effect are not fully understood. This paper focuses on reviewing the literature to define the effect of Pentoxifylline when used in liver ischemia and reperfusion injury. Our research shows different animal models in which Pentoxifylline has been used as well as different doses and time of administration, as the ideal dose and timing have not yet been ascertained in liver ischemia and reperfusion. In conclusion, Pentoxifylline has shown positive effects in liver ischemia and reperfusion injury, and the main mechanism seems to be associated with the inhibition of TNF-α.

Protective effect of N-acetylcysteine against ischemia/reperfusion injury in rat urinary bladders

Ischemia/reperfusion (I/R) injury represents an important cause of bladder contractile dysfunction. One of the major causes leading to this dysfunction is thought to be reactive oxygen species formation. In this study, we investigated the potential benefit of N-acetylcysteine (NAC), a potent antioxidant that neutralizes free radicals, in a rat model of urinary bladder injury. NAC treatment rescues the reduction of contractile response to I/R injury in a dose-dependent manner. In addition, all levels of reactive oxygen species, lipid peroxidation, and NADPH-stimulated superoxide production in the I/R operation+NAC (I/R+NAC) group also decreased compared with a marked increase in the I/R operation+saline (I/R+S) group. Moreover, an in situ fluorohistological approach also showed that NAC reduces the generation of intracellular superoxides enlarged by I/R injury. Together, our findings suggest that NAC has a protective effect against the I/R-induced bladder contractile dysfunction via radical scavenging property.