Pirfenidone protects endotoxin-induced liver injury after hepatic ischemia in rats

The effects of pirfenidone on ischaemia-reperfusion injury in testicular torsion-induced rat model

The aim of this study was to analyse the effect of pirfenidone against ischaemia-reperfusion injury occurring after detorsion in rats with induced testicular torsion model. Group 1 was assigned as the control group. Group 2 first had testis torsion performed, and then, testicular detorsion was performed. Group 3 had similar procedures to the rats in Group 2. Rats in Group 3 additionally had 325 mg/kg pirfenidone administered immediately after ischaemia. The blood samples were analysed spectrophotometrically. To determine the intensity of tissue injury, haemorrhage, oedema and congestion levels were evaluated with direct microscopic investigation of testis. Seminiferous tubule architecture, spermatogenesis processes and germ cell maturation were graded by Johnsen and Cosentino scoring systems. In Group 3, superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities increased compared with Group 2 (p:.03 and p:.049 respectively). Additionally, the mean malondialdehyde (MDA) value was higher in Group 2 compared with the other groups (p:.001). Histopathological investigation of rats in Group 3 identified positive changes in haemorrhage, oedema and congestion levels compared with Group 2 (p:.031, p:.048, p:.044 respectively). Similarly, Johnsen and Cosentino scores were positively affected in Group 3 (p:.033, p:.032 respectively). Pirfenidone is protective against testicular oxidative damage.

Pirfenidone attenuates gentamicin-induced acute kidney injury by inhibiting inflammasome-dependent NLRP3 pathway in rats

Acute kidney injury (AKI) is an abrupt and usually reversible decline in renal function. AKI is considered one of the main drawbacks of the use of gentamicin that critically limits its clinical use. In this study, pirfenidone, an oral antifibrotic drug, was given to rats (200 mg/kg, p.o., daily) for seven days alone before the initiation of gentamicin treatment and continued for seven days alongside daily gentamicin injections. In gentamicin group, gentamicin was given to Wistar rats (100 mg/kg, i.p., daily) for seven days to induce AKI. Pirfenidone managed to alleviate gentamicin-induced AKI by improving kidney function parameters including serum creatinine, blood urea nitrogen (BUN), proteinuria, relative kidney-to-body weight ratio and creatinine clearance. Pirfenidone decreased cytotoxicity induced by gentamicin by decreasing lactate dehydrogenase (LDH) activity and improving histologic picture of tubules and glomeruli. Pirfenidone also alleviated oxidative stress induced by gentamicin by reducing malondialdehyde (MDA) and elevating reduced glutathione (GSH). Pirfenidone prevented the upregulated inflammasome pathway markers in the kidney. It succeeded in decreasing toll like recpetor-4 (TLR4), nuclear factor-kappa B (NF-κB), nucleotide-binding oligomerization domain [NOD]-like pyrin domain containing protein 3 (NLRP3), caspase-1, interleukin-1β (IL-1β) and IL-18 levels. Additionally, Pirfenidone caused a decrease in macrophage infiltration displayed by reduction in renal monocyte chemoattractant protein-1 (MCP-1) levels. To sum up, pirfenidone can effectively mitigate gentamicin-induced AKI by inhibiting oxidative stress, macrophage infiltration and inflammasome-dependent NLRP3 pathway-induced inflammation.

Pirfenidone alleviates lung ischemia-reperfusion injury in a rat model

OBJECTIVE

Lung ischemia-reperfusion injury is among the complications seen after lung transplantation, resulting in morbidity and mortality. Pirfenidone, an antifibrotic agent for the treatment of idiopathic pulmonary fibrosis, is reported to have cytoprotective properties in various disease models. The purpose of this study was to investigate the effect of pirfenidone on lung ischemia-reperfusion injury.

METHODS

Male Lewis rats (260-290 g) were divided into 3 groups: sham group (n = 5), warm ischemia (WI) group (n = 10), and WI plus pirfenidone (WI+PFD) group (n = 10). The sham group underwent 210 minutes of perfusion without ischemia. The WI and WI+PFD groups underwent 90 minutes of warm ischemia and 120 minutes of reperfusion. In the WI+PFD group, pirfenidone (300 mg/kg) was administered orally by gavage 30 minutes before ischemia. After reperfusion, arterial blood gas analysis, lung mechanics, lung wet-to-dry weight ratio, and histologic findings were obtained. The gene expressions of proinflammatory cytokines in lung tissue were measured by quantitative reverse transcription polymerase chain reaction.

RESULTS

Compared with the WI group, the WI+PFD group had significantly better dynamic pulmonary compliance (P < .01) and oxygenation levels (P < .05). The wet-to-dry ratio was lower in the WI+PFD group (P < .05). Histologic analysis showed that the WI+PFD group had reduced perivascular edema and neutrophil infiltration. The expression of tumor necrosis factor-α messenger RNA was decreased in the WI+PFD group (P < .05).

CONCLUSIONS

Our results revealed that in a rat hilar clamp model, pirfenidone alleviated lung ischemia-reperfusion through anti-inflammatory effects.

Antifibrotic therapy in simian immunodeficiency virus infection preserves CD4+ T-cell populations and improves immune reconstitution with antiretroviral therapy

Even with prolonged antiretroviral therapy (ART), many human immunodeficiency virus-infected individuals have <500 CD4(+) T cells/µL, and CD4(+) T cells in lymphoid tissues remain severely depleted, due in part to fibrosis of the paracortical T-cell zone (TZ) that impairs homeostatic mechanisms required for T-cell survival. We therefore used antifibrotic therapy in simian immunodeficiency virus-infected rhesus macaques to determine whether decreased TZ fibrosis would improve reconstitution of peripheral and lymphoid CD4(+) T cells. Treatment with the antifibrotic drug pirfenidone preserved TZ architecture and was associated with significantly larger populations of CD4(+) T cells in peripheral blood and lymphoid tissues. Combining pirfenidone with an ART regimen was associated with greater preservation of CD4(+) T cells than ART alone and was also associated with higher pirfenidone concentrations. These data support a potential role for antifibrotic drug treatment as adjunctive therapy with ART to improve immune reconstitution.

Butyrate protects rat liver against total hepatic ischemia reperfusion injury with bowel congestion

Hepatic ischemia/reperfusion (I/R) injury is an unavoidable consequence of major liver surgery, especially in liver transplantation with bowel congestion, during which endotoxemia is often evident. The inflammatory response aggravated by endotoxin after I/R contributes to liver dysfunction and failure. The purpose of the present study was to investigate the protective effect of butyrate, a naturally occurring four-carbon fatty acid in the body and a dietary component of foods such as cheese and butter, on hepatic injury complicated by enterogenous endotoxin, as well as to examine the underlying mechanisms involved. SD rats were subjected to a total hepatic ischemia for 30 min after pretreatment with either vehicle or butyrate, followed by 6 h and 24 h of reperfusion. Butyrate preconditioning markedly improved hepatic function and histology, as indicated by reduced transaminase levels and ameliorated tissue pathological changes. The inflammatory factors levels, macrophages activation, TLR4 expression, and neutrophil infiltration in live were attenuated by butyrate. Butyrate also maintained the intestinal barrier structures, reversed the aberrant expression of ZO-1, and decreased the endotoxin translocation. We conclude that butyrate inhibition of endotoxin translocation, macrophages activation, inflammatory factors production, and neutrophil infiltration is involved in the alleviation of total hepatic I/R liver injury in rats. This suggests that butyrate should potentially be utilized in liver transplantation.

Investigational approaches to therapies for idiopathic pulmonary fibrosis

IMPORTANCE OF THE FIELD

In fibrosing diseases, scar tissue begins to replace normal tissue, causing tissue dysfunction. For instance, in lung fibrosis, foci of what resembles scar tissue form in the lungs, impeding the ability of patients to breathe. These conditions represent a significant source of morbidity and mortality. More than 150,000 people in the USA have some form of fibrotic lung disease, and the 5-year mortality rate for these diseases can be as high as 80%. Despite this large unmet medical need, there are no FDA-approved therapies. Although our understanding of the causes and the biology of fibrosing diseases remains relatively poor, we have made impressive advances in identifying the major cell populations and many biochemical mediators that can drive this process. As a result, novel therapeutics are being developed based upon these discoveries.

AREAS COVERED IN THIS REVIEW

This review examines the experimental therapies currently under investigation as of late 2009 for a major class of lung fibrosis called idiopathic pulmonary fibrosis (IPF).

WHAT THE READER WILL GAIN

The reader will gain an overview of current experimental therapies for IPF.

TAKE HOME MESSAGE

With the recent approval of Pirfenidone in Japan for use in IPF, and a rich pipeline of experimental therapies in various stages of clinical development, the future looks bright for new treatment options.

Protective effect of bicyclol on liver injury induced by hepatic warm ischemia/reperfusion in rats

AIM

Bicyclol is a synthetic anti-hepatitis drug with anti-oxidative property. The purpose of this study was to investigate the effect of bicyclol on hepatic ischemia/reperfusion (I/R) injury and related mechanisms.

METHODS

Rats were subjected to 90 min of hepatic ischemia followed by reperfusion for 1, 3, 6 and 24 h. Three doses of bicyclol were orally administered before ischemia. Liver injury was evaluated by biochemical and histopathological examinations. Liver malondialdehyde (MDA), superoxide dismutase (SOD), nitric oxide (NO), inducible nitric oxide synthase (iNOS) and myeloperoxidase (MPO) contents, and plasma endotoxin levels were spectrophotometrically measured. The expressions of inflammatory and anti-inflammatory cytokines were detected by reverse transcription polymerase chain reaction and enzyme-linked immunosorbent assay. Liver intercellular adhesion molecule-1 (ICAM-1) was examined by immunohistochemistry, and the expressions of nuclear factor (NF)-kappaB, inhibitor of NF-kappaB (IkappaB) and toll-like receptor 4 (TLR4) were determined by western blot.

RESULTS

Bicyclol significantly inhibited the elevations of serum alanine aminotransferase, total bilirubin and plasma endotoxin levels, alleviated the formation of liver MDA and nitrite/nitrate, restored impaired antioxidant SOD, attenuated hepatic necrosis and neutrophil infiltration, and also improved the 7-day survival in I/R rats. Additionally, bicyclol markedly downregulated the overexpression of ICAM-1, modulated the expression of inflammatory/anti-inflammatory cytokines and inhibited the expression of NF-kappaB and TLR4 in I/R rats.

CONCLUSION

Bicyclol had a remarkable protective effect on hepatic I/R injury, which was partially due to inhibiting the expression of TLR4 and NF-kappaB via its ability to attenuate oxidative stress and endotoxin.

Pirfenidone: a novel potential therapeutic agent in the management of chronic allograft rejection

Chronic allograft dysfunction is a leading cause of allograft failure, morbidity, and mortality after solid organ transplantation. The pathogenesis of chronic allograft failure has a final common pathway leading to organ fibrosis. Pirfenidone is an effective and novel antifibrotic agent with anti-inflammatory properties. Clinical use of the agent has been tested in a number of nontransplant recipients and has a favorable safety profile based on available clinical data. Building on these observations and findings, and considering the role of fibrosis in chronic allograft rejection, pirfenidone was initially investigated as adjunct therapy in a rat heterotopic tracheal transplantation model. This led to several studies confirming that pirfenidone may well be worth considering for further investigation. This paper reviews the possibility of using pirfenidone in clinical transplantation management.

Simple determination of pirfenidone in rat plasma via high-performance liquid chromatography

A simple, rapid and reliable high-performance liquid chromatographic method was developed and validated for the determination of pirfenidone and its major metabolites in rat plasma. Plasma proteins were precipitated with perchloric acid (10%, v/v) and the supernatant after centrifugation was determined using high-performance liquid chromatography. The analysis was carried out on a Lichrospher C(18) column (250 x 4.6 mm i.d., 5 microm). The mobile phase consisted of acetonitrile-water containing 0.2% acetic acid (23:77, v/v) at a flow-rate of 1 mL/min. The eluant was detected at 310 nm. The calibration curves were linear over a concentration range from 0.15 to 76.67 microg/mL. The accuracy (relative error) of the assay ranged from -2.6 to 7.9% and the precision (coefficient of variation) was less than 4.5%. The established method has been successfully applied to a pharmacokinetic study of pirfenidone following a single oral dose to rats.

Treatment of patients with non-alcoholic fatty liver disease: current views and perspectives

Non-alcoholic fatty liver disease is considered a component of the metabolic syndrome associated with obesity. Problems still exist concerning non-alcoholic fatty liver disease patients in clinical practice, for example: (a) how to diagnose non-alcoholic fatty liver disease and its type; (b) how to select patients candidate to treatment; (c) how to treat selected patients. Non-alcoholic fatty liver disease includes steatosis and non-alcoholic steatohepatitis, but only non-alcoholic steatohepatitis evolves into cirrhosis and the absolute risk of mortality for non-alcoholic fatty liver disease is low. As yet, no tools, other than liver biopsy, are available to differentiate the various types of non-alcoholic fatty liver disease. Many drugs are, currently, under study to treat non-alcoholic fatty liver disease, even if well-performed trials are until necessary to define the best treatment. At the moment, the entity of the problem and the characteristics of patients frequently put the physician, in clinical practice, to choose the therapeutic approach arbitrarily which is considered more effective for each individual patient. Probably the future will consider the possibility of treating non-alcoholic fatty liver disease with more than one drug, by considering the various aspects and degree of this syndrome. Actually each physician should select the individual treatment on the basis of his/her knowledge and experience, by never forgetting the old saying 'primum non nocere'. However, the epidemiological entity of the problem, the characteristics of the patients, generally young, the frequent lack of clinical evidence of involvement of the liver, are all the factors that require vast well-performed clinical trials in order to define the best therapeutic approach for each individual patient.

Pirfenidone inhibits inflammatory responses and ameliorates allograft injury in a rat lung transplant model

OBJECTIVE

Tumor necrosis factor alpha is a proinflammatory cytokine that has been proved to play a crucial role in inducing posttransplantation lung injury. The present study was performed to determine whether pirfenidone, a new nonpeptide drug with potent anti-tumor necrosis factor alpha activity, promotes protection against acute allograft injury through inhibiting pulmonary inflammatory responses in a rat model of orthotopic lung transplantation.

METHODS

Three transplant groups were formed: isografts, untreated allografts, and allografts treated with pirfenidone (0.5% chow starting on day 1 after transplantation). The implants were harvested on day 21 after transplantation. Acute cellular rejection grade and degree of allograft injury were evaluated on the basis of hematoxylin-and-eosin staining. The pulmonary inflammatory response and inflammation-induced oxidative stress were assessed on the basis of neutrophil accumulation (myeloperoxidase immunoreactivity and enzymatic activity) and iron deposition (Prussian blue staining). In addition, circulating levels of tissue necrosis factor alpha in all animals were measured.

RESULTS

The degree of allograft injury was significantly reduced in pirfenidone-treated allografts relative to untreated allografts (P < .01). The beneficial effect of pirfenidone was associated with decreased lung myeloperoxidase immunoreactivity (P < .05) and enzymatic activity (P < .01). Moreover, the untreated allografts contained a high concentration of iron, which was strikingly reduced by pirfenidone. Treatment with pirfenidone resulted in a lower level of plasma tissue necrosis factor alpha, which correlated positively with lung myeloperoxidase enzymatic activity (P < .0001).

CONCLUSION

These results suggest that pirfenidone, with its anti-tissue necrosis factor alpha activity, reduced neutrophil recruitment and iron accumulation, hence limiting the acute lung allograft injury.