Inhibition of TNF-α protects against hepatic ischemia-reperfusion injury in rats via NF-κB dependent pathway

Inflammatory setting, therapeutic strategies targeting some pro-inflammatory cytokines and pathways in mitigating ischemia/reperfusion-induced hepatic injury: a comprehensive review

Ischemia/reperfusion injury (IRI) is a key determining agent in the pathophysiology of clinical organ dysfunction. It is characterized by an aseptic local inflammatory reaction due to a decrease in blood supply, hence deprivation of dependent oxygen and nutrients. In instances of liver transplantation, this injury may have irreversible implications, resulting in eventual organ rejection. The deterioration associated with IRI is affected by the hepatic health status and various factors such as alterations in metabolism, oxidative stress, and pro-inflammatory cytokines. The primary cause of inflammation is the initial immune response of pro-inflammatory cytokines, while Kupffer cells (KFCs) and neutrophil-produced chemokines also play a significant role. Upon reperfusion, the activation of inflammatory responses can elicit further cellular damage and organ dysfunction. This review discusses the interplay between chemokines, pro-inflammatory cytokines, and other inflammatory mediators that contribute to the damage to hepatocytes and liver failure in rats following IR. Furthermore, it delves into the impact of anti-inflammatory therapies in safeguarding against liver failure and hepatocellular damage in rats following IR. This review investigates the correlation between cytokine factors and liver dysfunction via examining databases, such as PubMed, Google Scholar, Science Direct, Egyptian Knowledge Bank (EKB), and Research Gate.

Traumatic inflammatory response: pathophysiological role and clinical value of cytokines

Severe trauma is an intractable problem in healthcare. Patients have a widespread immune system response that is complex and vital to survival. Excessive inflammatory response is the main cause of poor prognosis and poor therapeutic effect of medications in trauma patients. Cytokines are signaling proteins that play critical roles in the body's response to injuries, which could amplify or suppress immune responses. Studies have demonstrated that cytokines are closely related to the severity of injuries and prognosis of trauma patients and help present cytokine-based diagnosis and treatment plans for trauma patients. In this review, we introduce the pathophysiological mechanisms of a traumatic inflammatory response and the role of cytokines in trauma patients. Furthermore, we discuss the potential of cytokine-based diagnosis and therapy for post-traumatic inflammatory response, although further clarification to elucidate the underlying mechanisms of cytokines following trauma is warranted.

Apoptotic cell death in disease-Current understanding of the NCCD 2023

Apoptosis is a form of regulated cell death (RCD) that involves proteases of the caspase family. Pharmacological and genetic strategies that experimentally inhibit or delay apoptosis in mammalian systems have elucidated the key contribution of this process not only to (post-)embryonic development and adult tissue homeostasis, but also to the etiology of multiple human disorders. Consistent with this notion, while defects in the molecular machinery for apoptotic cell death impair organismal development and promote oncogenesis, the unwarranted activation of apoptosis promotes cell loss and tissue damage in the context of various neurological, cardiovascular, renal, hepatic, infectious, neoplastic and inflammatory conditions. Here, the Nomenclature Committee on Cell Death (NCCD) gathered to critically summarize an abundant pre-clinical literature mechanistically linking the core apoptotic apparatus to organismal homeostasis in the context of disease.

Local injection of bone-marrow derived mesenchymal stromal cells alters a molecular expression profile of a contact frostbite injury wound and improves healing in a rat model

INTRODUCTION

Frostbite is a traumatic injury of the tissues upon low temperature environment exposure, which is characterized by direct cell injury due to freezing-thawing followed by development of an acute inflammatory process. Severe frostbite can lead to necrosis of soft tissues and loss of a limb. Mesenchymal stromal cells (MSCs) have a unique ability to modulate pathogenic immune response by secretion of paracrine factors, which suppress inflammation and mediate more efficient tissue regeneration. It should be noted that potential of stem cell therapy for frostbite injury treatment has not been investigated so far. Here, we evaluated a healing capacity of bone-marrow derived MSCs for the treatment of contact frostbite injury wound in a rat model.

METHODS

Cold-contact injury in a Wistar rat model was induced by 1-minute tight application of the cooled probe (-196 ⁰C) to the skin surface of the left hip. Rat bone marrow MSCs were phenotypically characterized and used for local injections into non-damaged tissues surrounding the wound of animals from the experimental group. The second group of rats was treated in the same manner with 1 mL of isotonic sodium chloride solution. Analysis of cytokine and growth factor expression profile in сold-contact injury wounds was performed on days 5, 9, and 16 using immunoblotting and enzyme-linked immunosorbent assay. Animal recovery in MSC-treated and vehicle-treated groups was evaluated by several criteria including body weight recording, determination of eschar desquamation and re-epithelialization terms, assessment of wound closure kinetics, and histological scoring of the wounds on day 23.

RESULTS

It turned out that a single subcutaneous administration of MSCs around the wound site resulted in elevated expression of pro-survival and pro-angiogenic VEGF-A and PDGF and 3-5-fold decrease in pro-inflammatory IL-1β as compared with the frostbite wound treated with a vehicle. Moreover, treatment with MSCs caused accelerated wound re-epithelialization (p < 0.05) as well as a better histological score of the MSC-treated wounds.

CONCLUSIONS

Thus, our data suggested that the use of MSCs is a promising therapeutic strategy for the treatment of cold-induced injury wounds.

Anxiety, depression, and memory loss in Chagas disease: a puzzle far beyond neuroinflammation to be unpicked and solved

Mental disorders such as anxiety, depression, and memory loss have been described in patients with chronic Chagas disease (CD), a neglected tropical disease caused by the protozoan parasite Trypanosoma cruzi. Social, psychological, and biological stressors may take part in these processes. There is a consensus on the recognition of an acute nervous form of CD. In chronic CD patients, a neurological form is associated with immunosuppression and neurobehavioural changes as sequelae of stroke. The chronic nervous form of CD has been refuted, based on the absence of histopathological lesions and neuroinflammation; however, computed tomography shows brain atrophy. Overall, in preclinical models of chronic T. cruzi infection in the absence of neuroinflammation, behavioural disorders such as anxiety and depression, and memory loss are related to brain atrophy, parasite persistence, oxidative stress, and cytokine production in the central nervous system. Interferon-gamma (IFNγ)-bearing microglial cells are colocalised with astrocytes carrying T. cruzi amastigote forms. In vitro studies suggest that IFNγ fuels astrocyte infection by T. cruzi and implicate IFNγ-stimulated infected astrocytes as sources of TNF and nitric oxide, which may also contribute to parasite persistence in the brain tissue and promote behavioural and neurocognitive changes. Preclinical trials in chronically infected mice targeting the TNF pathway or the parasite opened paths for therapeutic approaches with a beneficial impact on depression and memory loss. Despite the path taken, replicating aspects of the chronic CD and testing therapeutic schemes in preclinical models, these findings may get lost in translation as the chronic nervous form of CD does not fulfil biomedical model requirements, as the presence of neuroinflammation, to be recognised. It is hoped that brain atrophy and behavioural and neurocognitive changes are sufficient traits to bring the attention of researchers to study the biological and molecular basis of the central nervous system commitment in chronic CD.

Extracellular Vesicle Biomarkers Reveal Inhibition of Neuroinflammation by Infliximab in Association with Antidepressant Response in Adults with Bipolar Depression

Accumulating evidence suggests that neuroinflammation is involved in bipolar disorder (BD) pathogenesis. The tumor necrosis factor-alpha (TNF-α) antagonist infliximab was recently reported to improve depressive symptoms in a subpopulation of individuals with BD and history of childhood maltreatment. To explore the mechanistic mediators of infliximab's effects, we investigated its engagement with biomarkers of cellular response to inflammation derived from plasma extracellular vesicles enriched for neuronal origin (NEVs). We hypothesized that infliximab, compared to placebo, would decrease TNF-α receptors (TNFRs) and nuclear factor-kappa B (NF-κB) pathway signaling biomarkers, and that history of childhood abuse would moderate infliximab's effects. We immunocaptured NEVs from plasma samples collected at baseline and at weeks 2, 6, and 12 (endpoint) from 55 participants of this clinical trial and measured NEV biomarkers using immunoassays. A subset of participants (n = 27) also underwent whole-brain magnetic resonance imaging at baseline and endpoint. Childhood physical abuse moderated treatment by time interactions for TNFR1 (χ² = 9.275, p = 0.026), NF-κB (χ² = 13.825, p = 0.003), and inhibitor of NF-κB (IκBα) (χ² = 7.990, p = 0.046), indicating that higher levels of physical abuse were associated with larger biomarker decreases over time. Moreover, the antidepressant response to infliximab was moderated by TNFR1 (χ² = 7.997, p = 0.046). In infliximab-treated participants, reductions in TNFR1 levels were associated with improvement of depressive symptoms, an effect not detected in the placebo group. Conversely, reductions in TNFR1 levels were associated with increased global cortical thickness in infliximab- (r = -0.581, p = 0.029), but not placebo-treated, patients (r = 0.196, p = 0.501). In conclusion, we report that NEVs revealed that infliximab engaged the TNFR/NF-κB neuro-inflammatory pathway in individuals with BD, in a childhood trauma-dependent manner, which was associated with clinical response and brain structural changes.

Combination of pentoxifylline and α-galactosylceramide with radiotherapy promotes necro-apoptosis and leukocyte infiltration and reduces the mitosis rate in murine melanoma

Despite the success for the treatment of melanoma such as targeted molecular therapy, the use of such treatments are expensive For this reason, this study was carried out to explore the anti-cancer properties of available drugs that are able to modify the melanoma prognosis. The study was conducted in two phases: Evaluation of pharmacological effects of pentoxifylline (PTX) administered above (60 mg/kg) which is the therapeutic dose that is aimed at reducing the side-effect of radiotherapy, and of α- galactosylceramide (GalCer) administered at 100 μg/kg, as well as their combination using a murine model (BDF1 mice) of melanoma cell line (B16-F1, ATCC). For the radiotherapy phase, 9 Gy was applied in the tumor area, before (3 days), during (30 min) and after (3 days) the PTX + GalCer treatment. In both study phases, the mitosis rate, leukocyte infiltration and necro-apoptosis were assessed using histological and immunohistochemical approach and tumor volume evaluation as biomarkers. All treatments showed good prognosis results estimated as reduction of mitosis rate (PTX + GalCer after radiotherapy and GalCer), increased leukocyte infiltrate (PTX + GalCer after radiotherapy and GalCer) and necro-apoptosis augmentation (PTX + GalCer after radiotherapy and radiotherapy control). Nevertheless, a lower development of tumor volume was found in GalCer treatment. In this way, it is possible to suggest that the integrated treatment with immuno-stimulators such as GalCer, plus drug used for peripheral vascular disease (PTX) after radiotherapy is probably an alternative for controlling aggressive melanoma in murine model.

Intravenous infusion of ulinastatin attenuates acute kidney injury after cold ischemia/reperfusion

BACKGROUND

Administration of ulinastatin was proved to protect many organs from ischemia/reperfusion (I/R) induced injury, yet its protective effects on renal I/R injury under cold condition and mechanism still remain unclear.

AIMS

In the present study, the protective effects of ulinastatin on renal cold I/R injury as well as its mechanism were investigated.

METHODS AND RESULTS

Renal cold I/R model was constructed via cross-clamping of left renal artery and vein at 4 °C. The ulinastatin was administrated and multi-methods were performed to evaluate the protective effects. The results showed that ulinastatin could mitigate the renal cold I/R injury. In addition, the attenuated kidney cold I/R injury by ulinastatin was also accompanied with its regulating capability of the microenvironment, such as decreased acute inflammatory response, oxidative stress damage and apoptosis, as well as attenuation of vasculature levels decrease, as evidence by reduced TNF-α, IL-6 mRNA expression, MDA levels and apoptosis, higher levels of SOD activity and CD31/α-SMA expression.

CONCLUSION

The present study suggested that ulinastatin might be clinically useful in reducing preservation injury induced by cold I/R during renal transplantation surgery.

Ryanodine receptor antagonism alleviates skeletal muscle ischemia reperfusion injury by modulating TNF-α and IL-10

BACKGROUND

Intracellular calcium overload has been implicated in various pathological conditions including ischemia reperfusion injury. This study aims to explore the effect and probable mechanism of dantrolene, a ryanodine receptor and intracellular calcium antagonist, on the skeletal muscle ischemia reperfusion injury.

MATERIALS AND METHODS

SD rats were randomly divided into three groups: sham group which underwent anaesthesia and exposure of femoral vein, reperfusion group that received 2 h ischemia and the amount of diluent via femoral vein before 4 h reperfusion, dantrolene group that underwent 2 h ischemia and was given 2 mg/kg dantrolene via femoral vein before 4 h reperfusion. The parameters measured at the end of reperfusion included serum maleic dialdehyde (MDA), tissue myeloperoxidase (MPO) and muscle histology, as well as serum TNF-α and IL-10.

RESULTS

Levels of MDA, MPO and TNF-α increased in the reperfusion group, whereas the relevant expressions in the dantrolene group decreased significantly. Histological examination demonstrated significant improvements between the same both groups. IL-10 reflected the protection observed above with a significant up-regulation of expression after dantrolene administration.

CONCLUSION

Ryanodine receptor antagonist dantrolene exerted a significant protective effect against the inflammatory injury of skeletal muscle ischemia reperfusion. The underlying molecular mechanism is probably related to the suppression of TNF-α levels and the increment of IL-10 expression.

Adalimumab mitigates ovarian ischemia-reperfusion injury in rats by regulating oxidative stress, apoptosis and resolution of inflammation

AIM

Ovarian torsion is a rare but an important reason of acute lower abdominal pain in women and associated with serious morbidity and mortality, if not treated promptly. The aim of this study was to evaluate the effects of an antitumor necrosis factor-α antibody on ovarian torsion in a rat model of ischemia-reperfusion (I/R) injury.

METHODS

Forty female Wistar Albino rats were used in the present study. The rats were randomly divided into four groups: group I (sham), group II (I/R), group III (I/R + isotonic saline) and group IV (I/R + adalimumab). The I/R model was induced by torsion of both ovaries. Immunohistochemical staining for interleukin-1β (IL-1β), nuclear factor-κB (NF-κB), and inducible nitric oxide synthase was performed. Tissue and serum oxidative stress markers in conjunction with apoptotic index (AI) with the terminal deoxynucleotidyl transferase dUTP nick end labeling method were also calculated.

RESULTS

Tissue total oxidant status, oxidative stress index and nitric oxide values were significantly decreased, and tissue total antioxidant status was found to be increased in group IV. Inflammation, vascular congestion and hemorrhagia were significantly lower in adalimumab-treated group. Serum oxidative stress markers and tissue malondialdehyde levels did not differ in study groups. The AI was significantly increased in groups 2 and 3. Adalimumab treatment significantly decreased the AI.

CONCLUSION

Adalimumab therapy in rats attenuated I/R induced ovarian injury, possibly suppressing inflammation, inhibiting oxidative stress, and altering apoptotic pathways.

Ketamine ameliorates ischemia-reperfusion injury after liver autotransplantation by suppressing activation of Kupffer cells in rats

This study aimed to investigate the protective effects of ketamine against hepatic ischemia-reperfusion (I/R) injury by suppressing activation of Kupffer cells (KCs) in rat liver autotransplantation. Male Sprague-Dawley rats were randomized into 3 groups (n = 10 each). Group I, the sham group, received saline. Group II received saline and underwent orthotopic liver autotransplantation (OLAT). Group III received 10 mg/kg ketamine and underwent OLAT. Blood samples were obtained at 3, 6, 12, and 24 h after I/R, and following ALT, AST, LDH, IL-6, TNF-α, IL-1β, and IL-10 in serum were detected. Model rats were sacrificed at the indicated time points and the graft liver tissues were evaluated histologically. KCs were isolated from rat liver tissues, and inflammatory products and proteins of NF-κB signaling pathway were detected using quantitative RT-PCR and Western blotting. Our results showed that ketamine significantly decreased ALT, AST, LDH, IL-6, TNF-α, and IL-1β levels and increased IL-10 level. Furthermore, ketamine alleviated the histopathology changes, by less KC infiltration and lower hepatocyte apoptosis. Moreover, activity of NF-κB signaling pathway in KCs was suppressed. In addition, production of pro- and anti-inflammatory factors is consistent with the results in tissues. Ketamine ameliorated I/R injury after liver transplantation by suppressing activation of KCs in rats.

Liver X Receptors Activation Attenuates Ischemia Reperfusion Injury of Liver Graft in Rats

Purpose: Suppression of the Toll like receptor 4 (TLR4)-nuclear factor-κB (NF-κB) signaling was critical in protection against liver IRI. Previous studies revealed that Liver X receptors (LXRs) activation could antagonize TLR4-NF-κB signaling. The purpose of this study is to determine whether LXRs agonist GW3965 can suppress the TLR4-NF-κB signaling during liver transplantation and protect ischemia-reperfusion injury (IRI). Materials and Methods: Sprague Dawley (SD) rats were used to perform orthotropic liver transplantation. Donors were pretreatment with GW3965 (0.3 mg/kg) through caudal vein injection 30 min before the surgery. The followings were analyzed after transplantation: alanine aminotransferase (ALT), interleukin 6 (IL-6) and tumor necrosis factor α (TNF-α) level in serum, ATP binding cassette transporter A1 (Abca1) expression, NF-κB transcriptional activity, apoptosis and histological injury. Results: GW3965 pretreatment significantly ameliorated the degree of IRI associated with the effects of upregulating Abca1 expression, inhibiting NF-κB transcriptional activity, and downregulating TNF-α and IL-6 level. Conclusion: LXRs activation attenuated hepatic IRI by preventing TLR4-NF-κB signaling.

Priming astrocytes with TNF enhances their susceptibility to Trypanosoma cruzi infection and creates a self-sustaining inflammatory milieu

BACKGROUND

In conditions of immunosuppression, the central nervous sty 5ystem (CNS) is the main target tissue for the reactivation of infection by Trypanosoma cruzi, the causative agent of Chagas disease. In experimental T. cruzi infection, interferon gamma (IFNγ)⁺ microglial cells surround astrocytes harboring amastigote parasites. In vitro, IFNγ fuels astrocyte infection by T. cruzi, and IFNγ-stimulated infected astrocytes are implicated as potential sources of tumor necrosis factor (TNF). Pro-inflammatory cytokines trigger behavioral alterations. In T. cruzi-infected mice, administration of anti-TNF antibody hampers depressive-like behavior. Herein, we investigated the effects of TNF on astrocyte susceptibility to T. cruzi infection and the regulation of cytokine production.

METHODS

Primary astrocyte cultures of neonatal C57BL/6 and C3H/He mice and the human U-87 MG astrocyte lineage were infected with the Colombian T. cruzi strain. Cytokine production, particularly TNF, and TNF receptor 1 (TNFR1/p55) expression were analyzed. Recombinant cytokines (rIFNγ and rTNF), the anti-TNF antibody infliximab, and the TNFR1 modulator pentoxifylline were used to assess the in vitro effects of TNF on astrocyte susceptibility to T. cruzi infection. To investigate the role of TNF on CNS colonization by T. cruzi, infected mice were submitted to anti-TNF therapy.

RESULTS

rTNF priming of mouse and human astrocytes enhanced parasite/astrocyte interaction (i.e., the percentage of astrocytes invaded by trypomastigote parasites and the number of intracellular parasite forms/astrocyte). Furthermore, T. cruzi infection drove astrocytes to a pro-inflammatory profile with TNF and interleukin-6 production, which was amplified by rTNF treatment. Adding rTNF prior to infection fueled parasite growth and trypomastigote egression, in parallel with increased TNFR1 expression. Importantly, pentoxifylline inhibited the TNF-induced increase in astrocyte susceptibility to T. cruzi invasion. In T. cruzi-infected mice, anti-TNF therapy reduced the number of amastigote nests in the brain.

CONCLUSIONS

Our data implicate TNF as a promoter of T. cruzi invasion of mouse and human astrocytes. Moreover, the TNF-enriched inflammatory milieu and enhanced TNFR1 expression may favor TNF signaling, astrocyte colonization by T. cruzi and egression of trypomastigotes. Therefore, in T. cruzi infection, a self-sustaining TNF-induced inflammatory circuit may perpetuate the parasite cycle in the CNS and ultimately promote cytokine-driven behavioral alterations.

Anti-TNF-α Agent Infliximab and Splenectomy Are Protective Against Renal Ischemia-Reperfusion Injury

BACKGROUND

Renal ischemia-reperfusion (I/R) injury is associated with delayed graft function and results in poor long-term graft survival. We previously showed that splenectomy (SPLN) protects the kidney from I/R injury and reduces serum TNF-α levels. Herein, we further investigated the effects of SPLN on inflammatory responses and tissue injury in renal I/R by examining the expression of major inflammatory cytokines and heat shock protein 70 (HSP70). Because it was shown previously that the anti-TNF-α agent infliximab (IFX) attenuated renal I/R injury, we also investigated whether IFX administration mimics the effects of SPLN.

METHODS

The left renal pedicles of adult male Wistar rats were clamped for 45 minutes and then reperfused for 24 hours; right nephrectomy and SPLN were performed immediately. A separate cohort was administered IFX 1 hour before surgery in lieu of SPLN.

RESULTS

Serum creatinine and blood urea nitrogen levels were markedly elevated by I/R injury; these increases were significantly reversed by IFX. Furthermore, IFX inhibited the induction of inflammatory cytokines and HSP70 during renal I/R injury. Time-dependent profiles revealed that the expression of inflammatory cytokines was elevated immediately after I/R, whereas levels of HSP70, serum creatinine, and blood urea nitrogen began to rise 3 hours postreperfusion. Macrophages/monocytes were significantly increased in I/R-injured kidneys, but not in those administered IFX. The outcomes of SPLN mirrored those of IFX administration.

CONCLUSIONS

Splenectomy and TNF-α inhibition both protect the kidney from I/R injury by reducing the accumulation of renal macrophages/monocytes and induction of major inflammatory cytokines.

The effects of tramadol on hepatic ischemia/reperfusion injury in rats

Objectives:

Tramadol is a centrally acting synthetic analgesic. It has a cardioprotective effect against myocardial ischemia-reperfusion (I/R) injury in isolated rat heart. We hypothesized that tramadol may exert a similar protective effect on hepatic I/R injury. Hence, the current investigation was designed to study the possible protective effects of tramadol on experimentally-induced hepatic I/R injury in rats.

Materials and Methods:

Tramadol was administered 30 min before ischemia following which the rats were subjected to 45 min of ischemia followed by 1 h of reperfusion.

Results:

Tramadol attenuated hepatic injury induced by I/R as evidenced by the reduction of transaminases, structural changes, and apoptotic cell death. It decreased the level of inflammatory markers such as tumor necrosis factor-alpha (TNF-α), TNF-α/interleukin-10 (IL-10) ratio, and nuclear factor-κB gene expression. It also increased the anti-inflammatory cytokine, IL-10 levels in hepatic tissues. Furthermore, it reduced oxidative stress parameters except manganese superoxide dismutase activity.

Conclusion:

The results suggest that tramadol has hepatoprotective effects against hepatic I/R injury via anti-inflammatory, antiapoptotic, and antioxidant effects.

Expression of tubulin folding cofactor B in mouse hepatic ischemia-reperfusion injury

The aim of the present study was to investigate the association between tubulin folding cofactor B (TBCB) expression and ischemia-reperfusion injury (IRI) in mice. A total of 48 C57BL/6 mice were randomly divided into a control group (Sham, n=6) and an ischemia-reperfusion group (n=42). The ischemia-reperfusion group was further divided into 6 subgroups as per different times after reperfusion (2, 4, 6, 8, 12 and 24 h), with 7 mice per subgroup. A hepatic IRI model was established in mice by clamping the hepatic hilum. Morphology, serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), interleukin 6 (IL-6) and tumor necrosis factor-α (TNF-α), and the expression level of TBCB were detected. Compared with the control group, the livers from the ischemia-reperfusion group were significantly changed, particularly at 12 h following ischemia-reperfusion, with obvious hepatic cell degeneration and necrosis. The ALT, AST, IL-6 and TNF-α levels in the sera of the mice in the hepatic ischemia-reperfusion group were increased at all time points following ischemia-reperfusion, and were the highest at 12 h, demonstrating statistically significant differences when compared with the control group (P<0.05). Furthermore, the expression levels of TBCB, TNF-α and IL-6 were significantly increased at all time-points following ischemia-reperfusion, and were the most significant at 12 h. At 24 h following ischemia-reperfusion, the expression levels had decreased. The present study indicated that TBCB expression is associated with TNF-α and IL-6 expression levels in mice with hepatic ischemia-reperfusion, and may be key in the development of liver injury during ischemia-reperfusion in mice.

Helping prometheus: liver protection in acute hemorrhagic shock

Acute hemorrhagic hypovolemic shock is caused by a significant high blood loss and leads to hemodynamic instability. The decrease in intravascular volume results in cellular hypoxia and finally in damage to organs such as the liver and the kidney. The liver plays a decisive role in the development or prevention of multiple organ failure after hemorrhagic shock. Despite the large number of experimental studies, the knowledge of pathophysiological mechanisms in the liver after hemorrhagic shock is incomplete. The aim of this mini review was to provide an overview of the pathophysiological changes in liver function after acute hemorrhagic shock and to address treatment options to improve liver perfusion.

Infliximab Modulates Cisplatin-Induced Hepatotoxicity in Rats

BACKGROUND

Cisplatin (Cis) is one of the most commonly used antineoplastic drugs. It is used as chemotherapy for many solid organ malignancies such as brain, neck, male and female urogenital, vesical and pulmonary cancers. Infliximab blocks tumor necrosis factor alpha (TNF-α). Several studies have reported that infliximab ameliorates cell damage by reducing cytokine levels.

AIMS

We aimed to investigate whether infliximab has a preventive effect against cisplatin-induced hepatotoxicity and whether it has a synergistic effect when combined with Cis.

STUDY DESIGN

Animal experimentation.

METHODS

Male Wistar albino rats were divided in three groups as follows: Cis group, infliximab + Cis (CIN) group and the control group. Each group comprised 10 animals. Animals in the Cis group received an intraperitoneal single-dose injection of Cis (7 mg/kg). In the CIN group, a single dose of infliximab (7 mg/kg) was administered 72 h prior to the Cis injection. After 72 h, a single dose of Cis (7 mg/kg) was administered. All rats were sacrificed five days after Cis injection.

RESULTS

TNF-α levels in the Cis group were significantly higher (345.5±40.0 pg/mg protein) than those of the control (278.7±62.1 pg/mg protein, p=0.003) and CIN groups (239.0±64.2 pg/mg protein, p=0.013). The Cis group was found to have high carbonic anhydrase (CA)-II and low carbamoyl phosphate synthetase-1 (CPS-1) levels. Aspartate transaminase (AST) and alanine transaminase (ALT) levels were lower in the CIN group as compared to the Cis group. Total histological damage was greater in the Cis group as compared to the control and CIN groups.

CONCLUSION

Cis may lead to liver damage by increasing cytokine levels. It may increase oxidative stress-induced tissue damage by increasing carbonic anhydrase II (CA-II) enzyme levels and decreasing CPS-1 enzyme levels. Infliximab decreases Cis-induced hepatic damage by blocking TNF-α and it may also protect against liver damage by regulating CPS-1 and CA-II enzyme levels.

Hypothermia is better than ischemic preconditioning for preventing early hepatic ischemia/reperfusion in rats

BACKGROUND

Topical hypothermia (TH) and ischemic preconditioning (IPC) are used to decrease I/R injury. The efficacy of isolated or combined use of TH and IPC in the liver regarding inflammation and cytoprotection in early ischemia/reperfusion (I/R) injury needs to be evaluated.

MATERIAL AND METHODS

Wistar rats underwent 70% liver ischemia for 90 min followed by 120 min of reperfusion. Livers of animals allocated in the sham, normothermic ischemia (NI), IPC, TH, and TH+IPC groups were collected for molecular analyses by ELISA and Western blot, aiming to compare proinflammatory, anti-inflammatory, and antioxidant profiles.

RESULTS

Compared with NI, TH presented decreased tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6 and IL-12 concentrations and increased IL-10 levels. TH animals displayed lower inducible nitric oxide synthase (iNOS) and higher endothelial nitric oxide synthase (eNOS) expressions. NAD(P)H-quinone oxidoreductase-1(NQO1) expression was also lower with TH. Isolated IPC and NI were similar regarding all these markers. TH+IPC was associated with decreased IL-12 concentration and reduced iNOS and NQO1 expressions, similarly to isolated TH. Expression of Kelch-like ECH-associated protein (Keap)-1 was increased and expression of nuclear and cytosolic nuclear erythroid 2-related factor 2 (Nrf2) was decreased with TH+IPC vs. NI.

CONCLUSION

TH was the most effective method of protection against early I/R injury. Isolated IPC entailed triggering of second-line antioxidant defense enzymes. Combined TH+IPC seemed to confer no additional advantage over isolated TH in relation to the inflammatory process, but had the advantage of completely avoid second-line antioxidant defense enzymes.

Infliximab Modulates Cisplatin-Induced Hepatotoxicity in Rats

BACKGROUND

Cisplatin (Cis) is one of the most commonly used antineoplastic drugs. It is used as chemotherapy for many solid organ malignancies such as brain, neck, male and female urogenital, vesical and pulmonary cancers. Infliximab blocks tumor necrosis factor alpha (TNF-α). Several studies have reported that infliximab ameliorates cell damage by reducing cytokine levels.

AIMS

We aimed to investigate whether infliximab has a preventive effect against cisplatin-induced hepatotoxicity and whether it has a synergistic effect when combined with Cis.

STUDY DESIGN

Animal experimentation.

METHODS

Male Wistar albino rats were divided in three groups as follows: Cis group, infliximab + Cis (CIN) group and the control group. Each group comprised 10 animals. Animals in the Cis group received an intraperitoneal single-dose injection of Cis (7 mg/kg). In the CIN group, a single dose of infliximab (7 mg/kg) was administered 72 h prior to the Cis injection. After 72 h, a single dose of Cis (7 mg/kg) was administered. All rats were sacrificed five days after Cis injection.

RESULTS

TNF-α levels in the Cis group were significantly higher (345.5±40.0 pg/mg protein) than those of the control (278.7±62.1 pg/mg protein, p=0.003) and CIN groups (239.0±64.2 pg/mg protein, p=0.013). The Cis group was found to have high carbonic anhydrase (CA)-II and low carbamoyl phosphate synthetase-1 (CPS-1) levels. Aspartate transaminase (AST) and alanine transaminase (ALT) levels were lower in the CIN group as compared to the Cis group. Total histological damage was greater in the Cis group as compared to the control and CIN groups.

CONCLUSION

Cis may lead to liver damage by increasing cytokine levels. It may increase oxidative stress-induced tissue damage by increasing carbonic anhydrase II (CA-II) enzyme levels and decreasing CPS-1 enzyme levels. Infliximab decreases Cis-induced hepatic damage by blocking TNF-α and it may also protect against liver damage by regulating CPS-1 and CA-II enzyme levels.

The Effects of Infliximab on Laminin, NFκB, and Anti-TNF Expression through Its Effect on Ischemic Liver Tissue

The aim of this study was to investigate the possible protective effects of infliximab on expression of laminin, anti-TNF, and NFκB in the rat hepatic cells after ischemia/reperfusion (I/R). A total of 30 male Wistar albino rats were divided into three groups: Control (C), sham I/R (ISC), and I/R+ infliximab (ISC inf); each group comprised 10 animals. C group animals underwent laparotomy without I/R injury. In ISC groups after undergoing laparotomy, 1 hour of superior mesenteric artery ligation was done, which was followed by 1 hour of reperfusion. In the ISC inf group, 3 days before I/R, infliximab (3 mg/kg) was administered intravenously. All animals were killed at the end of reperfusion and hepatic tissue samples were obtained for histopathological and histochemical investigations in all groups. Laminin, anti-TNF, and NFκB immunoreactivity were performed for all groups. ISC caused severe histopathological injury including mucosal erosions, inflammatory cell infiltration, necrosis, hemorrhage, and villous congestion. Infliximab treatment significantly attenuated the severity of intestinal I/R injury and it is shown by laminin, anti-TNF, and NFκB immunoreactivity. Because of its anti-inflammatory and antioxidant effects, infliximab pretreatment may have protective effects on hepatic cells in the experimental intestinal I/R model of rats.

Pentoxifylline during steroid window phase at induction to remission increases apoptosis in childhood with acute lymphoblastic leukemia

PURPOSE

Pentoxifylline (PTX) has been shown to increase chemotherapy-induced apoptosis. A clinical trial was developed to evaluate the effect of the addition of PTX to the induction steroid window phase in children with acute lymphoblastic leukemia (ALL).

METHODS

Thirty-two children were enrolled on this study. Children with a new diagnosis of ALL were randomly assigned to receive prednisone (PRD) 40 mg/m(2)/day only during the 7-day treatment pre-phase (PRD group, 11 patients) or to receive PRD with PTX (10 mg/kg/day) (PTX group, 11 patients); the control group included children with normal bone marrow (10 patients). Bone marrow aspiration (BMA) was performed at diagnosis (day -7) in all groups, and at day 0 (end of PRD window) for patients with ALL (PRD and PTX groups). Apoptosis was evaluated by flow cytometry (FC) using Annexin V-fluorescein isothiocyanate (FITC)/propidium iodide (PI) stains. Statistical analysis was performed using the Mann-Whitney U test.

RESULTS

Apoptotic index at day -7 was similar in all groups. However, at day 0 post-treatment, apoptosis was significantly higher in the PTX group than in the PRD group (p < 0.001). There were no serious adverse effects associated with PTX.

CONCLUSIONS

PTX potentiates blast apoptosis induced by PRD in children with ALL during steroid window phase.

Acute liver injury attenuation of a novel recombinant sTNFR through blocking hepatic apoptosis

CONTEXT

Tumor necrosis factor (TNF) α plays a key role in acute liver injury (ALI) induced by injection of d-galactosamine (D-Gal)/lipopolysaccharide (LPS). A novel recombinant trimeric sTNFRII, sTNFRII-gAD, has been tested to be effective in ameliorating ALI, when administered prior to ALI establishment. This study aims to validate the protective effect of sTNFRII-gAD when given after ALI setup and further explore its effect on hepatic apoptosis.

MATERIALS AND METHODS

The treatments were carried out concomitantly with ALI establishment with clinically approved sTNFRII-Fc (the dimeric sTNFRII) as a positive control. Lethality, liver weight, and serum alanine transaminase were measured, and histological analysis was performed to evaluate liver injury induced by D-Gal/LPS. Additionally, Terminal-deoxynucleoitidyl transferase-mediated nick end labeling (TUNEL) and Western blot analyses of caspase-3 were used to examine hepatocellular apoptosis.

RESULTS

sTNFRII-gAD given after D-Gal/LPS injection turned out to attenuate animal mortality significantly (p < 0.01), and had better hepatic protection. In terms of apoptosis, both sTNFRII-gAD and sTNFRII-Fc displayed noticeable improvement of apoptosis evidenced by dramatic decline of active caspase-3 compared to the control group.

CONCLUSIONS

The results demonstrated that sTNFRII-gAD therapeutically diminished the lethality induced by D-Gal/LPS, possibly through blocking hepatic apoptosis initiated by TNFα. Of note, sTNFRII-gAD was superior to sTNFRII-Fc in some respects, indicating a promising alternative for the therapeutic strategy against the diseases associated with excessive TNFα.

Pentoxifylline reverses chronic experimental Chagasic cardiomyopathy in association with repositioning of abnormal CD8+ T-cell response

Background

Chronic chagasic cardiomyopathy (CCC), the main clinical sign of Chagas disease, is associated with systemic CD8⁺ T-cell abnormalities and CD8-enriched myocarditis occurring in an inflammatory milieu. Pentoxifylline (PTX), a phosphodiesterase inhibitor, has immunoregulatory and cardioprotective properties. Here, we tested PTX effects on CD8⁺ T-cell abnormalities and cardiac alterations using a model of experimental Chagas’ heart disease.

Methodology/Principal Findings

C57BL/6 mice chronically infected by the Colombian Trypanosoma cruzi strain and presenting signs of CCC were treated with PTX. The downmodulation of T-cell receptors on CD8⁺ cells induced by T. cruzi infection was rescued by PTX therapy. Also, PTX reduced the frequency of CD8⁺ T-cells expressing activation and migration markers in the spleen and the activation of blood vessel endothelial cells and the intensity of inflammation in the heart tissue. Although preserved interferon-gamma production systemically and in the cardiac tissue, PTX therapy reduced the number of perforin⁺ cells invading this tissue. PTX did not alter parasite load, but hampered the progression of heart injury, improving connexin 43 expression and decreasing fibronectin overdeposition. Further, PTX reversed electrical abnormalities as bradycardia and prolonged PR, QTc and QRS intervals in chronically infected mice. Moreover, PTX therapy improved heart remodeling since reduced left ventricular (LV) hypertrophy and restored the decreased LV ejection fraction.

Conclusions/Significance

PTX therapy ameliorates critical aspects of CCC and repositioned CD8⁺ T-cell response towards homeostasis, reinforcing that immunological abnormalities are crucially linked, as cause or effect, to CCC. Therefore, PTX emerges as a candidate to treat the non-beneficial immune deregulation associated with chronic Chagas' heart disease and to improve prognosis.

Chronic chagasic cardiomyopathy (CCC) is the main clinical manifestation of Chagas disease (CD), a neglected illness caused by the protozoan parasite Trypanosoma cruzi. More than hundred years after its discovery, CD continues to be a public health problem and millions of chronically infected people wait for an effective treatment. Chagasic cardiomyopathy is associated with CD8⁺ T-cell-enriched myocarditis, fibrosis and cardiac electrical and structural abnormalities, frequently progressing to heart failure. Presently, the available therapies only mitigate symptoms of CCC. Abnormalities in CD8⁺ T-cell compartment are present in CCC patients. Recently, we described the importance of CD8⁺ T-cells in the pathogenesis of CCC. Therefore, our proposal was to interfere with abnormalities of CD8⁺ T-cells glimpsing a better prognosis for CCC. Using PTX, an affordable drug with immunomodulatory properties on T-cells and cardioprotective effects in non-infections disease, we bring a therapeutic candidate for treating CCC. PTX therapy downmodulated detrimental CD8⁺ T-cells and promoted T. cruzi-specific interferon-gamma-producing T-cells. Importantly, chronic chagasic electrical and echocardiographic alterations were reversed by PTX therapy. Future studies may test the use of PTX combined with trypanocidal drug or as a vaccine adjuvant to improve the quality of life of chronic CD patients.

Effect of infliximab against cisplatin-induced nephrotoxicity

OBJECTIVES

To investigate whether infliximab (Ib), an inhibitor of tumor necrosis factor alpha (TNF-α), prevents cisplatin (Cis)-induced nephrotoxicity.

METHODS

The study was performed in the Department of Internal Medicine, Recep Tayyip Erdogan University, Rize, Turkey, between November 2012 and May 2013. Thirty male Wistar albino rats were divided into 3 groups, a control group, a Cis group, and a Cis+Ib group. The animals of the Cis group were injected with a single dose (7 mg/kg) of Cis intraperitoneally. The animals of the Cis+Ib group were injected with a single dose (7 mg/kg) of Ib 72 hours prior to Cis injection.

RESULTS

The TNF-α, interleukin-1 beta (IL-1b), nitric oxide (NO) and adenosine deaminase (ADA) levels of the Cis group were higher than both the control group TNF-α (p<0.001), IL-1α (p<0.001), NO (p<0.001) and ADA (p<0.001), and the Cis+Ib group TNF-α (p<0.001), IL-1b (p<0.001), NO (p<0.001), and ADA (p=0.003). Histopathological examination revealed extensive damage in the Cis group, while the damage in the Cis+Ib group was lower. While the carbonic anhydrase II (CA-II) level of the Cis group was lower than both groups, it was similar in the Cis+Ib and the control groups.

CONCLUSION

Infliximab acts against Cis-induced nephrotoxicity by a strong inhibition of TNF-α. Additionally, the combination of these 2 drugs does not obviously change the level of CA-II.

Tumour necrosis factor-α promotes liver ischaemia-reperfusion injury through the PGC-1α/Mfn2 pathway

Tumour necrosis factor (TNF)-α has been considered to induce ischaemia-reperfusion injury (IRI) of liver which is characterized by energy dysmetabolism. Peroxisome proliferator–activated receptor-γ co-activator (PGC)-1α and mitofusion2 (Mfn2) are reported to be involved in the regulation of mitochondrial function. However, whether PGC-1α and Mfn2 form a pathway that mediates liver IRI, and if so, what the underlying involvement is in that pathway remain unclear. In this study, L02 cells administered recombinant human TNF-α had increased TNF-α levels and resulted in down-regulation of PGC-1α and Mfn2 in a rat liver IRI model. This was associated with hepatic mitochondrial swelling, decreased adenosine triphosphate (ATP) production, and increased levels of reactive oxygen species (ROS) and alanine aminotransferase (ALT) activity as well as cell apoptosis. Inhibition of TNF-α by neutralizing antibody reversed PGC-1α and Mfn2 expression, and decreased hepatic injury and cell apoptosis both in cell culture and in animals. Treatment by rosiglitazone sustained PGC-1α and Mfn2 expression both in IR livers, and L02 cells treated with TNF-α as indicated by increased hepatic mitochondrial integrity and ATP production, reduced ROS and ALT activity as well as decreased cell apoptosis. Overexpression of Mfn2 by lentiviral-Mfn2 transfection decreased hepatic injury in IR livers and L02 cells treated with TNF-α. However, there was no up-regulation of PGC-1α. These findings suggest that PGC-1α and Mfn2 constitute a regulatory pathway, and play a critical role in TNF-α-induced hepatic IRI. Inhibition of the TNF-α or PGC-1α/Mfn2 pathways may represent novel therapeutic interventions for hepatic IRI.

Evaluation of oxidative stress in the late postoperative stage of liver transplantation

INTRODUCTION

Liver transplant recipients are at an increased oxidative stress risk due to pre-existing hepatic impairment, ischemia-reperfusion injury, immunosuppression, and functional graft rejection. This study compared the oxidative status of healthy control subjects, patients with liver cirrhosis on the list for transplantation, and subjects already transplanted for at least 12 months.

PATIENTS AND METHODS

Sixty adult male patients, aged between 27 and 67 years, were subdivided into 3 groups: a control group (15 healthy volunteers), a cirrhosis group (15 volunteers), and a transplant group (30 volunteers). Oxidative stress was evaluated by activity of reduced glutathione, malondialdehyde, and vitamin E.

RESULTS

There was a significant difference (P < .01) in the plasma concentration of reduced glutathione in the 3 groups, with the lowest values observed in the transplanted group. The malondialdehyde values differed significantly (P < .01) among the 3 groups, with the transplanted group again having the lowest concentrations. The lowest concentrations of vitamin E were observed in patients with cirrhosis compared with control subjects, and there was a significant correlation (P < .05) among the 3 groups. No correlations were found between reduced glutathione and vitamin E or between vitamin E and malondialdehyde. However, there were strong correlations between plasma malondialdehyde and reduced glutathione in the 3 groups: control group, r = 0.9972 and P < .0001; cirrhotic group, r = 0.9765 and P < .0001; and transplanted group, r = 0.8981 and P < .0001.

CONCLUSIONS

In the late postoperative stage of liver transplantation, oxidative stress persists but in attenuated form.

Adalimumab ameliorates abdominal aorta cross clamping which induced liver injury in rats

The aim of this study was to investigate the possible protective effects of adalimumab (ADA) on cell damage in rat liver tissue during ischemia/reperfusion (I/R) injury of infrarenal abdominal aorta. Thirty male Wistar-albino rats were divided into three groups: control, I/R, and I/R+ADA, each group containing 10 animals. Laparotomy without I/R injury was performed in the control group animals. Laparotomy in the I/R group was followed by two hours of infrarenal abdominal aortic cross ligation and then two hours of reperfusion. ADA (50 mg/kg) was administered intraperitoneally as a single dose, to the I/R+ADA group, five days before I/R. The tumor necrosis factor-alpha (TNF-α) (pg/mg protein) and nitric oxide (NO) (µmol/g protein) levels in the I/R group (430.8 ± 70.1, 8.0 ± 1.1, resp.) were significantly higher than those in the I/R+ADA group (338.0 ± 71.6, P = 0.006; 6.3 ± 1.2, P = 0.008) and the control group (345.5 ± 53.3, P = 0.008; 6.5 ± 1.5, P = 0.010, resp.). I/R causes severe histopathological injury to the liver tissue, but ADA leads to much less histopathological changes. ADA treatment significantly decreased the severity of liver I/R injury. ADA pretreatment may have protective effects on experimental liver injury.

Adalimumab ameliorates abdominal aorta cross clamping which induced liver injury in rats

The aim of this study was to investigate the possible protective effects of adalimumab (ADA) on cell damage in rat liver tissue during ischemia/reperfusion (I/R) injury of infrarenal abdominal aorta. Thirty male Wistar-albino rats were divided into three groups: control, I/R, and I/R+ADA, each group containing 10 animals. Laparotomy without I/R injury was performed in the control group animals. Laparotomy in the I/R group was followed by two hours of infrarenal abdominal aortic cross ligation and then two hours of reperfusion. ADA (50 mg/kg) was administered intraperitoneally as a single dose, to the I/R+ADA group, five days before I/R. The tumor necrosis factor-alpha (TNF-α) (pg/mg protein) and nitric oxide (NO) (µmol/g protein) levels in the I/R group (430.8 ± 70.1, 8.0 ± 1.1, resp.) were significantly higher than those in the I/R+ADA group (338.0 ± 71.6, P = 0.006; 6.3 ± 1.2, P = 0.008) and the control group (345.5 ± 53.3, P = 0.008; 6.5 ± 1.5, P = 0.010, resp.). I/R causes severe histopathological injury to the liver tissue, but ADA leads to much less histopathological changes. ADA treatment significantly decreased the severity of liver I/R injury. ADA pretreatment may have protective effects on experimental liver injury.

Inhibition of tumor necrosis factor alpha reduces the outgrowth of hepatic micrometastasis of colorectal tumors in a mouse model of liver ischemia-reperfusion injury

Background

Patients with colorectal cancer (CRC) often develop liver metastases, in which case surgery is considered the only potentially curative treatment option. However, liver surgery is associated with a risk of ischemia-reperfusion (IR) injury, which is thought to promote the growth of colorectal liver metastases. The influence of IR-induced tumor necrosis factor alpha (TNF-α) elevation in the process still is unknown. To investigate the role of TNF-α in the growth of pre-existing micrometastases in the liver following IR, we used a mouse model of colorectal liver metastases. In this model, mice received IR treatment seven days after intrasplenic injections of colorectal CT26 cells. Prior to IR treatment, either TNF-α blocker Enbrel or low-dose TNF-α, which could inhibit IR-induced TNF-α elevation, was administered by intraperitoneal injection.

Results

Hepatic IR treatment significantly promoted CT26 tumor growth in the liver, but either Enbrel or low-dose TNF-α pretreatment reversed this trend. Further studies showed that the CT26 + IR group prominently increased the levels of ALT and AST, liver necrosis, inflammatory infiltration and the expressions of hepatic IL-6, MMP9 and E-selectin compared to those of CT26 group. Inhibition of TNF-α elevation remarkably attenuated the increases of these liver inflammatory damage indicators and tumor-promoting factors.

Conclusion

These findings suggested that inhibition of TNF-α elevation delayed the IR-enhanced outgrowth of colorectal liver metastases by reducing IR-induced inflammatory damage and the formation of tumor-promoting microenvironments. Both Enbrel and low-dose TNF-α represented the potential therapeutic approaches for the protection of colorectal liver metastatic patients against IR injury-induced growth of liver micrometastases foci.

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.

Publication trends in Naunyn-Schmiedeberg's Archives of Pharmacology: focus on pharmacology in Egypt

In a previous analysis of the country of origin of papers published in Naunyn-Schmiedeberg's Archives of Pharmacology, a major shift toward contributions from emerging market countries, was noticed in comparison of 2010 to 2001 publications. Repeating such analysis for 2012 publications in the journal confirmed this trend. An interesting new trend was the emerging presence of papers from a variety of Islamic countries including Egypt. Based on this trend, we shortly review the history and current structure of pharmacology in Egypt. It appears that the presence of Egyptian pharmacology in international journals including pharmacology journals has sharply been increasing over the last two decades. Challenges for a continuation of this encouraging trend are being discussed.

Intraportal versus Systemic Pentoxifylline Infusion after Normothermic Liver Ischemia: Effects on Regional Blood Flow Redistribution and Hepatic Ischemia-Reperfusion Injury

Pentoxifylline (PTX) has been shown to have beneficial effects on microcirculatory blood flow. In this study we evaluate the potential hemodynamic and metabolic benefits of PTX during hepatic ischemia. We also test the hypothesis that portal PTX infusion can minimize the I/R injury when compared to systemic infusion. Methods. Twenty-four dogs (18.1 ± 0.7 kg) were subjected to portal triad occlusion (PTO) for 45 min. The animals were assigned to 3 groups: CT (control, PTO, n = 8), PTX-syst (PTO + 25 mg/Kg of PTX IV, n = 8), and PTX-pv (PTO + 25 mg/Kg of PTX in the portal vein, n = 8). Animals were followed for 120 min. Systemic hemodynamics, gastrointestinal tract perfusion, oxygen-derived variables, and liver enzymes were evaluated throughout the experiment. Results. Animals treated with PTX presented significantly higher CO in the first hour after reperfusion, when compared to the CT (~3.7 vs. 2.1 L/min, P < 0.05). Alanine aminotransferase (ALT) was similar in the PTX groups two hours after reperfusion but significantly higher in the CT (227 vs. ~64 U/L, P < 0.05). Conclusion. PTX infusion was associated with hemodynamic benefits and was able to minimize liver injury during normothermic hepatic I/R. However, local PTX infusion was not associated with any significant advantage over systemic route.

Matrix metalloprotease 9 promotes liver recovery from ischemia and reperfusion injury

BACKGROUND

Matrix metalloprotease (MMP) 9 has been always considered as a destructor of extracellular matrix, promoting liver injury and metastasis of carcinoma. In this study, we investigated the role of MMP-9 in liver wound healing from ischemia and reperfusion injury (IRI).

METHODS

MMP9-/- mice were used to establish partial hepatic IRI model. Serum alanine aminotransferase and hepatic cytokines (tumor necrosis factor alpha, interleukin [IL]-1β, IL-10, and transforming growth factor beta [TGF-β]) levels were analyzed after IRI. Hepatic stellate cells were isolated from wild-type mice to determine the effect of MMP-9 on TGF-β activation. In addition, the effect of TGF-β on liver wound healing from IRI was determined.

RESULTS

Liver recovery from IRI was impaired in MMP9-/- mice, which was described as elevated serum alanine aminotransferase, hepatic tumor necrosis factor alpha, and IL-1β levels. Meanwhile, TGF-β-active protein level was decreased in the liver of MMP9-/- mice. In vitro test, the activation of TGF-β was suppressed in the presence of anti-MMP-9 monoclonal antibody. TGF-β treatment promoted liver recovery from IRI in MMP9-/- mice.

CONCLUSIONS

MMP-9 promoted liver recovery from IRI by activating TGF-β. Thus, MMP-9 plays dual roles (bad and good) in liver IRI, depending on the timing.