Inhibition of endogenous TNF formation by pentoxifylline

Current Clinical Trials for Alcohol-Associated Hepatitis

Alcohol-associated hepatitis (AH) is a severe form of alcohol-associated liver disease (ALD) characterized by acute-onset jaundice and liver failure, which carries a high mortality risk, particularly in cases of severe AH (sAH). Although glucocorticoids have been the primary pharmacologic intervention for decades, their use is limited by a lack of long-term efficacy and significant side effects and relative contraindications. For patients who do not respond to glucocorticoids, early liver transplantation (eLT) is a life-saving option, yet only a few patients qualify for this intervention. In recent years, advances in translational medicine have uncovered key mechanisms in AH pathophysiology, including microbiome interactions, proinflammatory signaling, and disruptions in hepatocyte function. These insights have led to the exploration of innovative pharmacologic treatments, targeting pathways such as the gut-liver axis, oxidative stress, inflammation, and liver regeneration. Despite promising results from ongoing clinical trials, several challenges persist, including low patient recruitment and retention rates, heterogeneity in trial design, and the lack of standardized endpoints. This review assesses the current pharmacologic landscape of AH, emphasizing emerging therapies and the ongoing challenges in AH clinical trials.

Commonalities Between COVID-19 and Radiation Injury

As the multi-systemic components of COVID-19 emerge, parallel etiologies can be drawn between SARS-CoV-2 infection and radiation injuries. While some SARS-CoV-2-infected individuals present as asymptomatic, others exhibit mild symptoms that may include fever, cough, chills, and unusual symptoms like loss of taste and smell and reddening in the extremities (e.g., "COVID toes," suggestive of microvessel damage). Still others alarm healthcare providers with extreme and rapid onset of high-risk indicators of mortality that include acute respiratory distress syndrome (ARDS), multi-organ hypercoagulation, hypoxia and cardiovascular damage. Researchers are quickly refocusing their science to address this enigmatic virus that seems to unveil itself in new ways without discrimination. As investigators begin to identify early markers of disease, identification of common threads with other pathologies may provide some clues. Interestingly, years of research in the field of radiation biology documents the complex multiorgan nature of another disease state that occurs after exposure to high doses of radiation: the acute radiation syndrome (ARS). Inflammation is a key common player in COVID-19 and ARS, and drives the multi-system damage that dramatically alters biological homeostasis. Both conditions initiate a cytokine storm, with similar pro-inflammatory molecules increased and other anti-inflammatory molecules decreased. These changes manifest in a variety of ways, with a demonstrably higher health impact in patients having underlying medical conditions. The potentially dramatic human impact of ARS has guided the science that has identified many biomarkers of radiation exposure, established medical management strategies for ARS, and led to the development of medical countermeasures for use in the event of a radiation public health emergency. These efforts can now be leveraged to help elucidate mechanisms of action of COVID-19 injuries. Furthermore, this intersection between COVID-19 and ARS may point to approaches that could accelerate the discovery of treatments for both.

TNF-α inhibition decreases MMP-2 activity, reactive oxygen species formation and improves hypertensive vascular hypertrophy independent of its effects on blood pressure

Systemic arterial hypertension is a public health problem associated with an increased risk of cardiovascular disease. Matrix metalloproteinases (MMP) are endopeptidases that participate in hypertension-induced cardiovascular remodeling, which may be activated by oxidative stress. Angiotensin II (Ang II), a potent hypertrophic and vasoconstrictor peptide, increases oxidative stress, MMP-2 activity and tumor necrosis factor (TNF-α) expression. In vitro studies have shown that TNF-α is essential for Ang II-induced MMP-2 expression. Thus, this study evaluated whetherTNF-α inhibition decreases the development of hypertension-induced vascular remodeling via reduction of MMP-2 activity and reactive oxygen species (ROS) formation. Two distinct pharmacological approaches were used in the present study: Pentoxifylline (PTX), a non-selective inhibitor of phosphodiesterases that exerts anti- inflammatory effects via inhibition of TNF-α, and Etanercept (ETN), a selective TNF-α inhibitor. 2-kidney and 1-Clip (2K1C). 2-kidney and 1-Clip (2K1C) and Sham rats were treated with Vehicle, PTX (50 mg/Kg and 100 mg/kg daily) or ETN (0.3 mg/Kg and 1 mg/kg; three times per week). Systolic blood pressure (SBP) was measured weekly by tail cuff plethysmography. Plasma TNF-α and IL-1β levels were evaluated by enzyme-linked immunosorbent assay (ELISA) technique. The vascular hypertrophy was examined in the aorta sections stained with hematoxylin/eosin. ROS in aortas was evaluated by dihydroethidium and chemiluminescence lucigenin assay. Aortic MMP-2 levels and activity were evaluated by gel zymography and in situ zymography, respectively. The 2K1C animals showed a progressive increase in SBP levels and was accompanied by significant vascular hypertrophy (p < 0.05 vs Sham). Treatment with PTX at higher doses decreased SBP and vascular remodeling in 2K1C animals (p < 0.05 vs 2K1C vehicle). Although the highest dose of ETN treatment did not reduce blood pressure, the vascular hypertrophy was significantly attenuated in 2K1C animals treated with ETN1 (p < 0.05). The increased cytokine levels and ROS formation were reversed by the highest doses of both PTX and ETN. The increase in MMP-2 levels and activity in 2K1C animals were reduced by PTX100 and ETN1 treatments (p < 0.05 vs vehicle 2K1C). Lower doses of PTX and ETN did not affect any of the evaluated parameters in this study, except for a small reduction in TNF-α levels. The findings of the present study suggest that PTX and ETN treatment exerts immunomodulatory effects, blunted excessive ROS formation, and decreased renovascular hypertension-induced MMP-2 up-regulation, leading to improvement ofvascular remodeling typically found in 2K1C hypertension. Therefore, strategies using anti-hypertensive drugs in combination with TNF alpha inhibitors could be an attractive therapeutic approach to tackle hypertension and its associated vascular remodeling.

Systemic administration of pentoxifylline attenuates the development of hypertension in renovascular hypertensive rats

There is evidence to suggest that hypertension involves a chronic low-grade systemic inflammatory response; however, the underlying mechanisms are unclear. To further understand the role of inflammation in hypertension, we used a rat renovascular model of hypertension in which we administered the TNF-α synthesis inhibitor pentoxifylline (PTX, 30 mg/kg/day) in the drinking water for 60 days. In conscious rats, PTX administration significantly attenuated the development of hypertension (systolic blood pressure, PTX: 145 ± 8 vs. vehicle (Veh): 235 ± 11 mmHg, after 38 days of treatment, P < 0.05, N = 5/group). This attenuation in hypertension was coupled with a decrease in the low-frequency spectra of systolic blood pressure variability (PTX: 1.23 ± 0.2 vs Veh: 3.05 ± 0.8 arbitrary units, P < 0.05, N = 5/group). Furthermore, systemic PTX administration decreased c-Fos expression within the hypothalamic paraventricular nucleus (PTX: 17 ± 4 vs. Veh: 70 ± 13 cells, P < 0.01, N = 5, PVN) and increased the total number of microglial branches (PTX: 2129 ± 242 vs. Veh: 1415 ± 227 branches, P < 0.05, N = 4/group). Acute central injection of PTX (20 μg) under urethane anesthesia caused a small transient decrease in blood pressure but did not change renal sympathetic nerve activity. Surprisingly, we found no detectable basal levels of plasma TNF-α in either PTX- or vehicle-treated animals. These results suggest that inflammation plays a role in renovascular hypertension and that PTX might act both peripherally and centrally to prevent hypertension.

Targeting metabolic dysregulation for fibrosis therapy

Fibrosis is the abnormal deposition of extracellular matrix, which can lead to organ dysfunction, morbidity, and death. The disease burden caused by fibrosis is substantial, and there are currently no therapies that can prevent or reverse fibrosis. Metabolic alterations are increasingly recognized as an important pathogenic process that underlies fibrosis across many organ types. As a result, metabolically targeted therapies could become important strategies for fibrosis reduction. Indeed, some of the pathways targeted by antifibrotic drugs in development - such as the activation of transforming growth factor-β and the deposition of extracellular matrix - have metabolic implications. This Review summarizes the evidence to date and describes novel opportunities for the discovery and development of drugs for metabolic reprogramming, their associated challenges, and their utility in reducing fibrosis. Fibrotic therapies are potentially relevant to numerous common diseases such as cirrhosis, non-alcoholic steatohepatitis, chronic renal disease, heart failure, diabetes, idiopathic pulmonary fibrosis, and scleroderma.

Salivary levels of TNF-α in patients with recurrent aphthous stomatitis: A cross-sectional study

Background. Recurrent aphthous stomatitis (RAS) is a disorder characterized by recurring ulcers involving the oral mucosa in patients with no other signs of disease. The current concept of etiopathogenesis is that RAS is a clinical syndrome with several possible etiologies. The process seen in RAS is probably initiated through an as yet unidentified antigenic stimulation of the mucosal keratinocytes, which stimulates secretion of T-cell activation cytokines ‒ interleukins and tumor necrosis factor alpha (TNF-α). TNF-α causes inflammation by its effect on endothelial cell adhesion and neutrophil chemotaxis. The rele-vance of TNF-α to the pathogenesis of RAS has stemmed from the observations that anti- TNF-α drugs such as thalidomide and pentoxifylline have been found to be effective in the treatment of RAS. Therefore, the present study was an attempt to measure the levels of salivary TNF-α in patients with RAS, which will reflect the local production of cytokines at the site of the disease. The aim was to evaluate the salivary levels of TNF-α in patients with recurrent aphthous stomatitis.

Methods. The study comprised of 60 subjects, of whom 30 clinically proven RAS patients of either sex were selected as cases and 30 healthy, age- and gender- matched subjects were selected as controls. After taking informed consent, 5 mL of unstimulated saliva were collected from both the study and control group subjects. Determination of salivary TNF-α levels was carried out by Enzyme-Linked Immunosorbent Assay (ELISA) and expressed in pg/mL. Statistical analysis of the RAS and control groups was carried out using unpaired t-test. Gender-wise comparison of salivary TNF-α levels in the study and control groups was carried out using one-way ANOVA.

Results. Mean salivary TNF-α levels were significantly higher in the RAS group compared to the control group (P<0.001). It was also revealed that the mean salivary TNF-α levels in females were significantly higher than in males in the study group (PP<0.05).

Conclusion. It is fair to suggest that TNF-α plays a very important mediatory role in the pathogenesis of RAS and may play an important role in the search for a definitive treatment for the disease.

Effects of pentoxifylline on inflammatory markers and blood pressure: a systematic review and meta-analysis of randomized controlled trials

INTRODUCTION

Pentoxifylline is a xanthine derivative with potential cardiovascular benefits.

AIM

To evaluate the impact of pentoxifylline on blood pressure (BP) and plasma TNF-α, C-reactive protein (CRP) and IL-6 through a systematic review and meta-analysis of randomized controlled trials.

METHODS

The protocol was registered (PROSPERO: CRD42016035988). The search included PUBMED, ProQuest, Scopus and EMBASE until 1 September 2015 to identify trials reporting BP or inflammatory markers during pentoxifylline therapy. Quantitative data synthesis was performed using a random-effects model, with weighted mean difference (WDF) and 95% confidence intervals (CIs) as summary statistics.

RESULTS

Fifteen studies (16 treatment arms) were found to be eligible for inclusion. Meta-analysis did not suggest any effect of pentoxifylline on either SBP or DBP. Pentoxifylline treatment was associated with a significant reduction in plasma concentrations of TNF-α (WDF: -1.03 pg/ml, 95% CI: -1.54, -0.51; P < 0.001, 11 treatment arms) and CRP (WDF: -1.39 mg/l, 95% CI: -2.68, -0.10; P = 0.034, five treatment arms). No alteration in plasma IL-6 concentration was observed. The impact of pentoxifylline on plasma TNF-α levels was found to be positively associated with treatment duration (slope: 0.031; 95% CI: 0.004, 0.057; P = 0.023) but independent of pentoxifylline dose (slope: -0.0003; 95% CI: -0.002, 0.001; P = 0.687).

CONCLUSION

Pentoxifylline did not alter BP or plasma IL-6 concentration, but significantly reduced circulating TNF-α and CRP concentrations.

Pentoxifylline modulates LPS-induced hyperinflammation in monocytes of preterm infants in vitro

BackgroundPentoxifylline (PTX), a methylxanthine derivate with immunomodulating properties, has been used as adjunctive treatment in severe neonatal sepsis. The aim of the study was to investigate the anti-inflammatory effects of PTX on Lipopolysaccharides (LPS)-stimulated monocytes of preterm neonates in vitro compared with monocytes of term infants and adult controls.MethodsWhole cord blood samples and control adult blood samples were incubated with LPS and PTX. The expression of surface markers, phagocytosis, cytokine secretion, and Toll-like receptor (TLR)4 signaling of monocytes were assessed by flow cytometry. Changes of TLR4-messenger RNA (mRNA) levels were confirmed by reverse-transcriptase PCR.ResultsThe expression of CD14, CD11b, CD64, CD71, and CD80 was downregulated by PTX in a dose-dependent manner; the greatest effect was observed on CD14 and CD11b in preterm infants. PTX markedly downregulated LPS-induced tumor necrosis factor-α, interleukin (IL)-1β, and IL-6 levels in all age groups. Early IL-10 production was significantly downregulated by PTX in term and preterm neonates, while remaining unchanged in adults. Moreover, PTX downregulated TLR4 expression of monocytes on cellular and mRNA level, decreased signaling, and suppressed phagocytosis.ConclusionPTX downregulated TLR4 expression and signaling, thereby leading to strong anti-inflammatory properties in monocytes. Age-dependent differences were identified for CD14 and CD11b expression and IL-10 production.

Preventive Effect of Phosphodiesterase Inhibitor Pentoxifylline Against Medication-Related Osteonecrosis of the Jaw: An Animal Study

PURPOSE

The aim of this experimental study was to investigate the prophylactic effect of pentoxifylline (PTX) on medication-related osteonecrosis of the jaw (MRONJ).

MATERIALS AND METHODS

Female Sprague-Dawley rats (n = 33) received zoledronic acid (ZA) for 8 weeks to create an osteonecrosis model. The left mandibular second molars were extracted and the recovery period lasted 8 weeks before sacrifice. PTX was intraperitoneally administered to prevent MRONJ. The specimens were histopathologically and histomorphometrically evaluated.

RESULTS

Histomorphometrically, between the control and ZA groups, there was no statistically significant difference in total bone volume (P = .999), but there was a statistically significant difference in bone ratio in the extraction sockets (P < .001). A comparison of the bone ratio of the ZA group with the ZA/PTX group (PTX administered after extraction) showed no statistically significant difference (P = .69), but there was a statistically significant difference with the ZA/PTX/PTX group (PTX administered before and after extraction; P = .008). Histopathologically, between the control and ZA groups, there were statistically significant differences for inflammation (P = .013), vascularization (P = .022), hemorrhage (P = .025), and regeneration (P = .008). Between the ZA and ZA/PTX groups, there were no statistically significant differences for inflammation (P = .536), vascularization (P = .642), hemorrhage (P = .765), and regeneration (P = .127). Between the ZA and ZA/PTX/PTX groups, there were statistically significant differences for inflammation (P = .017), vascularization (P = .04), hemorrhage (P = .044), and regeneration (P = .04).

CONCLUSION

In this experimental model of MRONJ, it might be concluded that although PTX, given after tooth extraction, improves new bone formation that positively affects bone healing, it is not prophylactic. However, PTX given before tooth extraction is prophylactic. Therefore, PTX might affect healing in a positive way by optimizing the inflammatory response.

Protection of Pentoxifylline against Testis Injury Induced by Intermittent Hypobaric Hypoxia

To investigate the effect of pentoxifylline (PTX) on spermatogenesis dysfunction induced by intermittent hypobaric hypoxia (IHH) and unveil the underlying mechanism, experimental animals were assigned to Control, IHH+Vehicle, and IHH+PTX groups and exposed to 4 cycles of 96 h of hypobaric hypoxia followed by 96 h of normobaric normoxia for 32 days. PTX was administered for 32 days. Blood and tissue samples were collected 7 days thereafter. Serum malondialdehyde levels were used to assess lipid peroxidation; ferric-reducing antioxidant power (FRAP), superoxide dismutase, and catalase and glutathione peroxidase enzyme activities were assessed to determine antioxidant capacity in various samples. Testis histopathology was assessed after hematoxylin-eosin staining by Johnsen's testicular scoring system. Meanwhile, testosterone synthase and vimentin amounts were assessed by immunohistochemistry. Sperm count, motility, and density were assessed to determine epididymal sperm quality. IHH treatment induced significant pathological changes in testicular tissue and enhanced serum lipid peroxide levels, while reducing serum FRAP, antioxidant enzyme activities, and testosterone synthase expression. Moreover, IHH impaired epididymal sperm quality and vimentin structure in Sertoli cells. Oral administration of PTX improved the pathological changes in the testis. IHH may impair spermatogenesis function of testicular tissues by inducing oxidative stress, but this impairment could be attenuated by administration of PTX.

Hepatopulmonary Syndrome and Liver Transplantation: A Recent Review of the Literature

A severe and common pulmonary vascular complication of liver disease is hepatopulmonary syndrome (HPS). It is a triad of liver dysfunction and/or portal hypertension, intrapulmonary vascular dilatations, and increased alveolar-arterial oxygen gradient. Prevalence varies according to various study groups from 4%-47%. While the most common presenting symptom of HPS is dyspnea, it is usually asymptomatic, and thus all liver transplant candidates should be screened for its presence. Pulse oximetry is a useful screening method, but arterial blood gas examination is the gold standard. If there is an abnormal P (A-a)O2 gradient, microbubble transthoracic echocardiography should be done for diagnosis. Outcome is unpredictable, and there is currently no effective medical therapy. The only effective therapy is considered to be liver transplantation. Complete resolution of HPS after liver transplantation is seen within a year in most HPS patients.

Pentoxifylline alleviates hypertension in metabolic syndrome: effect on low-grade inflammation and angiotensin system

INTRODUCTION AND OBJECTIVE

Pentoxifylline is a well-tolerated drug used in treatment of vascular insufficiency. We previously showed that pentoxifylline protects from impairment in vascular reactivity in cases of metabolic syndrome. The aim of this study was to investigate the protective effect of pentoxifylline against hypertension in metabolic syndrome rats.

METHODS

Metabolic syndrome was induced by feeding rats a high-fructose, high-fat and high-salt diet for 12 weeks. Pentoxifylline was administered daily (30 mg kg(-1)) during the last 4 weeks of the study, before blood pressure parameters were assessed at the end of study. In addition, serum levels of glucose, fructosamine, insulin, tumor necrosis factor alpha, adiponectin, and lipid profile parameters were determined. Aortic protein levels of angiotensin II and angiotensin receptor 1 were assessed by immunofluorescence.

RESULTS

Pentoxifylline administration prevented excessive weight gain but did not affect hyperinsulinemia or hypertriglyceridemia seen in metabolic syndrome animals. In addition, pentoxifylline prevented the elevations in mean blood pressure associated with metabolic syndrome. Particularly, pentoxifylline prevented elevations in systolic, diastolic, and notch blood pressure; however, elevation in pulse blood pressure was not affected. Further, pentoxifylline alleviated the low-grade inflammation associated with metabolic syndrome, as reflected by the significantly lower serum tumor necrosis factor α and higher serum adiponectin levels metabolic syndrome animals treated with pentoxifylline. Also, pentoxifylline inhibited elevated expression of angiotensin receptor 1 in aortic tissue of metabolic syndrome animals.

CONCLUSION

Pentoxifylline directly alleviated hypertension in metabolic syndrome rats, at least in part, via amelioration of low-grade inflammation and inhibition of angiotensin system.

c-Rel regulates Ezh2 expression in activated lymphocytes and malignant lymphoid cells

The polycomb group protein Ezh2 is a histone methyltransferase that modifies chromatin structure to alter gene expression during embryonic development, lymphocyte activation, and tumorigenesis. The mechanism by which Ezh2 expression is regulated is not well defined. In the current study, we report that c-Rel is a critical activator of Ezh2 transcription in lymphoid cells. In activated primary murine B and T cells, plus human leukemia and multiple myeloma cell lines, recruitment of c-Rel to the first intron of the Ezh2 locus promoted Ezh2 mRNA expression. This up-regulation was abolished in activated c-Rel-deficient lymphocytes and by c-Rel knockdown in Jurkat T cells. Treatment of malignant cells with the c-Rel inhibitor pentoxifylline not only reduced c-Rel nuclear translocation and Ezh2 expression, but also enhanced their sensitivity to the Ezh2-specific drug, GSK126 through increased growth inhibition and cell death. In summary, our demonstration that c-Rel regulates Ezh2 expression in lymphocytes and malignant lymphoid cells reveals a novel transcriptional network in transformed lymphoid cells expressing high levels of Ezh2 that provides a molecular justification for combinatorial drug therapy.

Prognosis and treatment of patients with acute alcoholic hepatitis

Despite alcoholic hepatitis (AH) is the most acute manifestation of alcohol-related liver disease, its treatment remains controversial. Corticosteroids, given either as monotherapy or together with N-acetylecysteine, have been associated with a moderate short-term survival benefit in patients with severe disease. The Maddrey's discriminant function; Glasgow alcoholic hepatitis score; age, bilirubin, INR and creatinine score; and the Model for end-stage liver disease have been proposed for stratifying prognosis in AH enabling selection of the patients to treat. Definition of treatment non-responders using the Lille model after 7 days of therapy may prevent a detrimental impact of prolonged corticosteroids. Pentoxifylline is an effective alternative reducing the occurrence of hepatorenal syndrome. Emerging evidence supports use of liver transplantation in a strictly selected subset of corticosteroid non-responders.

Pentoxifylline decreases glycemia levels and TNF-alpha, iNOS and COX-2 expressions in diabetic rat pancreas

Pentoxifylline (PTX), a methyl xanthine derivative, is a phosphodiesterase inhibitor with anti-inflammatory and renoprotective effects in diabetic patients, among other properties. We studied PTX actions and mechanisms in reducing blood biochemical parameters, in diabetic rats. For diabetes induction, alloxan was intravenously administered to male Wistar rats. One group was left untreated and the other ones treated with PTX (25, 50 and 100 mg/kg), glibenclamide or metformin, as references. Forty-eight hours later and after 1-week to 3-month treatments, blood was collected for determination of glycemia, triglycerides, cholesterol, transaminases, fructosamine and glycated hemoglobin. Afterwards, the animals were euthanized and pancreas, liver and kidney processed for histological analyses and immunohistochemistry assays for TNF-alpha, iNOS and COX-2. The results showed that PTX decreased glycemia and also triglyceride levels, starting 1 week after treatments, as compared to the same group before treatments. Glycemia values were brought towards normality, after 1-month treatment. PTX hypoglycemic effects were potentiated by glibenclamide but not by metformin. It also decreased fructosamine and glycated hemoglobin. Some histological and immunohistochemical alterations for TNF-alpha, iNOS and COX-2 in the diabetic pancreas were also reversed by PTX. We conclude that PTX acts similarly to glibenclamide, and its hypoglycemic actions are, partly, a consequence of ATP-sensitive K(+) channels inhibition. In addition, by its anti-inflammatory and antioxidant properties, PTX may be a therapeutic alternative for the treatment of diabetes and its complications.

Therapeutic non-toxic doses of TNF induce significant regression in TNFR2-p75 knockdown Lewis lung carcinoma tumor implants

Tumor necrosis factor-alpha (TNF) binds to two receptors: TNFR1/p55-cytotoxic and TNFR2/p75-pro-survival. We have shown that tumor growth in p75 knockout (KO) mice was decreased more than 2-fold in Lewis lung carcinoma (LLCs). We hypothesized that selective blocking of TNFR2/p75 LLCs may sensitize them to TNF-induced apoptosis and affect the tumor growth. We implanted intact and p75 knockdown (KD)-LLCs (>90%, using shRNA) into wild type (WT) mice flanks. On day 8 post-inoculation, recombinant murine (rm) TNF-α (12.5 ng/gr of body weight) or saline was injected twice daily for 6 days. Tumor volumes (tV) were measured daily and tumor weights (tW) on day 15, when study was terminated due to large tumors in LLC+TNF group. Tubular bones, spleens and peripheral blood (PB) were examined to determine possible TNF toxicity. There was no significant difference in tV or tW between LLC minus (-) TNF and p75KD/LLC-TNF tumors. Compared to 3 control groups, p75KD/LLC+TNF showed >2-5-fold decreases in tV (p<0.001) and tW (p<0.0001). There was no difference in tV or tW end of study vs. before injections in p75KD/LLC+TNF group. In 3 other groups tV and tW were increased 2.7-4.5-fold (p<0.01, p<0.0002 and p<0.0001). Pathological examination revealed that 1/3 of p75KD/LLC+rmTNF tumors were 100% necrotic, the remaining revealed 40-60% necrosis. No toxicity was detected in bone marrow, spleen and peripheral blood. We concluded that blocking TNFR2/p75 in LLCs combined with intra-tumoral rmTNF injections inhibit LLC tumor growth. This could represent a novel and effective therapy against lung neoplasms and a new paradigm in cancer therapeutics.

Pharmacological treatment for hepatopulmonary syndrome

AIM

Hepatopulmonary syndrome is a pulmonary dysfunction in the context of liver cirrhosis characterized by arterial deoxygenation. Affected patients have increased morbidity and mortality, and many of them expire before undergoing liver transplantation. Therefore, finding medical therapy as a bridge to transplantation or as a final treatment is necessary. In this study, we aimed to review the current literature about pharmacological options available for treatment of hepatopulmonary syndrome.

METHODS

A PubMED and Scopus search was conducted in January 2013 on the English literature published in any time period to find human and animal studies reporting pharmacological therapy of hepatopulmonary syndrome.

RESULTS

Out of 451 studies, 29 relevant articles were included. The number of patients, type, dose, duration, and mechanism of drugs in these studies was extracted and summarized separately. Most of pharmacologic agents act through inhibition of nitric oxide synthase and reduction in nitric oxide production, inactivation of endothelin-1, and treatment of bacterial translocation and pulmonary angiogenesis.

CONCLUSION

Several drugs have been applied for the treatment of HPS with conflicting results. However, no large randomized trial has been conducted probably due to low number of patients. Multicentered clinical trials are necessary to investigate these drugs.

Preventive and therapeutic anti-TNF-α therapy with pentoxifylline decreases arthritis and the associated periodontal co-morbidity in mice

AIMS

The association between rheumatoid arthritis (RA) and periodontal disease (PD) has long been studied and some reports suggest that treating RA may improve the associated PD, and vice versa. This study aimed to evaluate the effects of an anti-tumor necrosis factor (TNF)-α therapy with pentoxifylline (PTX) in an experimental model of RA-associated PD.

MAIN METHODS

Male C57BL/6 mice were subjected to chronic antigen-induced arthritis (AIA) and daily treated with PTX (50mg/kg, i.p.) using preventive (Pre-PTX) or therapeutic (The-PTX) strategies. Fourteen days after the antigen challenge, mice were euthanized and knee joints, maxillae and serum were collected for microscopic and/or immunoenzymatic analysis.

KEY FINDINGS

AIA triggered significant leukocyte recruitment to the synovial cavity, tissue damage and proteoglycan loss in the knee joint. Pre-PTX and The-PTX regimens decreased these signs of joint inflammation. The increased levels of TNF-α and IL-17 in periarticular tissues of AIA mice were also reduced by both PTX treatments. Serum levels of C-reactive protein, which were augmented after AIA, were reduced by the PTX regimens. Concomitantly to AIA, mice presented alveolar bone loss, and recruitment of osteoclasts and neutrophils to periodontal tissues. Pre-PTX and The-PTX prevented and treated these signs of PD. PTX treatment also decreased TNF-α and increased IL-10 expression in the maxillae of AIA mice, although it did not affect the expression of IFN-γ and IL-17.

SIGNIFICANCE

The current study shows the anti-inflammatory and bone protective effects of preventive and therapeutic PTX treatments, which decreased the joint damage triggered by AIA and the associated periodontal co-morbidity.

Valproic acid: an anticonvulsant drug with potent antinociceptive and anti-inflammatory properties

Valproic acid (VA) is a major antiepileptic drug, used for several therapeutic indications. It has a wide activity spectrum, reflecting on mechanisms of action that are not fully understood. The objectives of this work were to study the effects of VA on acute models of nociception and inflammation in rodents. VA (0.5, 1, 10, 25, and 50 mg/kg, p.o.) effects were evaluated on the carrageenan-induced paw edema, carrageenan-induced peritonitis, and plantar tests in rats, as well as by the formalin test in mice. The HE staining and immunohistochemistry assay for TNF-α in carrageenan-induced edema, from paws of untreated and VA-treated rats, were also carried out. VA decreased paw edema after carrageenan, and maximum effects were seen with doses equal to or higher than 10 mg/kg. VA also preserved the tissue architecture as assessed by the HE staining. Immunohistochemical studies revealed that VA significantly reduced TNF-α immunostaining in carrageenan-inflamed rat paws. In addition, the anti-inflammatory action of VA was potentiated by pentoxifylline (a phosphodiesterase inhibitor, known to inhibit TNF-α production), but not by sodium butyrate or by suberoylanilide hydroxamic acid (SAHA), nonspecific and specific inhibitors, respectively, of histone deacetylase. However, the decrease in the number of positive TNF-α cells in the rat paw was drastically potentiated in the VA + SAHA associated group. VA also reduced leukocytes and myeloperoxidase (MPO) releases to the peritoneal exudate, in the carrageenan-induced peritonitis. Although in the formalin test, VA inhibited both phases, the inhibition was mainly on the second phase. Furthermore, VA significantly increased the reaction time to thermal stimuli, as assessed by the plantar test. VA is a multi-target drug, presenting potent antinociceptive and anti-inflammatory properties at a lower dose range. These effects are partly dependent upon its inhibitory action on TNF-α-related pathways. However, the participation of the HDAC inhibition with the VA anti-inflammatory action cannot be ruled out. Inflammatory processes are associated with free radical damage and oxidative stress, and their blockade by VA could also explain the present results.

Optimizing postoperative sexual function after radical prostatectomy

Erectile dysfunction (ED) is one of the complications associated with pelvic surgery. The significance of ED as a complication following pelvic surgery, especially radical prostatectomy (RP), lies in the negative impact that it has on patients' sexual and overall life. In the literature, rates of ED following RP range from 25% to 100%. Such variety is associated with pelvic dissection and conservation of neurovascular structures. Another important factor impacting on postoperative ED is the preoperative erectile function of the patient. Advances in the knowledge of pelvic anatomy and pathological mechanisms led to a refinement of pelvic surgical techniques, with attention to the main structures that if damaged compromise erectile function. These improvements resulted in lower postoperative ED rates and better erectile recovery, especially in patients undergoing RP. Furthermore, surgery alone is not sufficient to prevent this complication, and thus, several medical strategies have been tested with the aim of maximizing erectile function recovery. Indeed it seems that prevention of postoperative ED must be addressed by a multimodal approach. The aim of this review is to give a picture of recent knowledge, novel techniques and therapeutic approaches in order to reach the best combination of treatments to reduce the rate of ED after pelvic surgery.

Protective effect of pentoxifylline on amikacin-induced ototoxicity in rats

PURPOSE

This experimental study was performed to investigate the possible protective effect of pentoxifylline (PTX) on amikacin-induced ototoxicity in rats.

MATERIALS AND METHODS

In this study, 21 healthy female rats were randomly assigned to 1 of 3 groups: the amikacin group (n = 8), the amikacin + PTX group (n = 8), and the control group (n = 5). The amikacin group received amikacin (200 mg·kg(-1)·day(-1)) intramuscularly once daily for 14 days. The amikacin + PTX group received intramuscular injections of amikacin (200 mg·kg(-1)·day(-1)) once daily for 14 days and PTX (25 mg·kg(-1)·day(-1)) once daily via gastric gavage for 14 days. The control group received saline solution (1 mL·day(-1) intraperitoneal injections) once daily for 14 days. The hearing levels of the rats were evaluated using distortion product otoacoustic emissions before and after treatment.

RESULTS

The distortion product otoacoustic emissions' amplitude levels (decibel, sound pressure levels) measured before and after treatment at frequencies of 4000, 6000, and 8000 Hz revealed that values of the amikacin group dropped significantly at the end of treatment (P < .01). In contrast, the amikacin + PTX and the control groups showed no significant difference at the end of the treatment compared with the initial measurements (P > .05).

CONCLUSION

The results showed that PTX has protective effects on hearing functions in amikacin-induced ototoxicity in rats.

Pentoxifylline as a rescue treatment for DMD: a randomized double-blind clinical trial

OBJECTIVE

To determine whether pentoxifylline (PTX) slows the decline of muscle strength and function in ambulatory boys with Duchenne muscular dystrophy (DMD).

METHODS

This was a multicenter, randomized, double-blinded, controlled trial comparing 12 months of daily treatment with PTX or placebo in corticosteroid-treated boys with DMD using a slow-release PTX formulation (~20 mg/kg/day). The primary outcome was the change in mean total quantitative muscle testing (QMT) score. Secondary outcomes included changes in QMT subscales, manual muscle strength, pulmonary function, and timed function tests. Outcomes were compared using Student t tests and a linear mixed-effects model. Adverse events (AEs) were compared using the Fisher exact test.

RESULTS

A total of 64 boys with DMD with a mean age of 9.9 ± 2.9 years were randomly assigned to PTX or placebo in 11 participating Cooperative International Neuromuscular Research Group centers. There was no significant difference between PTX and the placebo group in total QMT scores (p = 0.14) or in most of the secondary outcomes after a 12-month treatment. The use of PTX was associated with mild to moderate gastrointestinal or hematologic AEs.

CONCLUSION

The addition of PTX to corticosteroid-treated boys with DMD at a moderate to late ambulatory stage of disease did not improve or halt the deterioration of muscle strength and function over a 12-month study period.

CLASSIFICATION OF EVIDENCE

This study provides Class I evidence that treatment with PTX does not prevent deterioration in muscle function or strength in corticosteroid-treated boys with DMD.

Immunopathogenesis of falciparum malaria: implications for adjunctive therapy in the management of severe and cerebral malaria

Despite optimal antimalarial treatment and advances in malaria eradication, the mortality rate associated with severe malaria due to Plasmodium falciparum infection, including cerebral malaria (CM), remains unacceptably high. This suggests that strategies directed solely at parasite eradication may be insufficient to prevent neurological complications and death in all cases of CM. Therefore, there is an urgent need to develop innovative adjunctive therapeutic strategies to effectively reduce CM-associated mortality. CM pathogenesis is believed to be due, in part, to an aberrant host immune response to P. falciparum, resulting in deleterious consequences, including vascular activation and dysfunction. Development of effective and affordable therapeutic strategies that act to modulate the underlying host-mediated immunopathology should be explored to improve outcome. In this article, we summarize immunomodulatory therapies that have been assessed in clinical trials to date, and highlight novel and promising treatment strategies currently being investigated to address this major global health challenge.

Randomized, placebo controlled study of the effect of propentofylline on survival time and quality of life of cats with feline infectious peritonitis

Background

Currently there is no drug proven to effectively treat cats with feline infectious peritonitis (FIP).

Hypothesis

Propentofylline (PPF) can decrease vasculitis, and therefore prolong survival time in cats with FIP, and increase their quality of life.

Animals

Twenty‐three privately owned cats with FIP.

Methods

Placebo‐controlled double‐blind trial. FIP was confirmed by histology or immunostaining of feline coronavirus (FCoV) antigen in effusion or tissue macrophages or both. The cats were randomly selected for treatment with either PPF or placebo. All cats received additional treatment with glucocorticoids, antibiotics, and low molecular weight heparin according to methods.

Results

There was no statistically significant difference in the survival time of cats treated with PPF (8 days, 95% CI 5.4–10.6) versus placebo (7.5 days, 95% CI 4.4–9.6). The median survival time of all cats was 8 days (4–36 days). There was neither a difference in quality of life (day 7, P = .892), in the amount of effusion (day 7, P = .710), the tumor necrosis factor‐alpha (TNF‐α) concentration (day 7, P = .355), nor in any other variable investigated in this study, including a complete blood count, and a small animal biochemistry profile.

Conclusions and Clinical Importance

This study did not detect an effect of PPF on the survival time, the quality of life, or any clinical or laboratory parameter in cats with FIP. Therefore, PPF does not appear to be an effective treatment option in cats with a late stage of the disease FIP.

Recurrent aphthous stomatitis

Recurrent aphthous ulcers are common painful mucosal conditions affecting the oral cavity. Despite their high prevalence, etiopathogenesis remains unclear. This review article summarizes the clinical presentation, diagnostic criteria, and recent trends in the management of recurrent apthous stomatitis.

Modulating effects of nonselective and selective phosphodiesterase inhibitors on lymphocyte subsets and humoral immune response in mice

Phosphodiesterase (PDE) inhibitors can regulate the activity of immune cells by increasing intracellular levels of cyclic nucleotides. The aim of this study was to determine the effects of milrinone, a selective PDE3 inhibitor, sildenafil, a selective PDE5 inhibitor, and aminophylline, a nonselective PDE inhibitor, on lymphocyte subsets and humoral immune response in mice when administered in vivo. Aminophylline (20 mg/kg, i.m.), milrinone (1 mg/kg, i.m.) or sildenafil (1 mg/kg, p.o.) were administered to mice either once or five times at 24 h intervals. Some mice were immunized with a sheep red blood cell (SRBC) suspension administered i.p. either 2 h after the single dose or 2 h after the second of the five doses. In non-immunized mice treated five times with PDE inhibitors, the subsets of T lymphocytes in the thymus and T and B lymphocytes in the spleen and mesenteric lymph nodes were determined 12, 24 or 72 h after the last dose. The humoral immune response was determined on days 4, 7 and 14 after SRBC injection in SRBC-immunized mice treated with PDE inhibitors. A modulating effect of the drugs on lymphocyte subpopulations was observed. The greatest impact was observed in splenocyte subpopulations, and resulted in decreased percentages of B cells (CD19(+)) and increased percentages of T cells (CD3(+), CD4(+), CD8(+)). No effect or slight influence of the drugs on anti-SRBC hemagglutinins was observed, but the number of plaque-forming splenocytes was increased. The drugs under investigation did not show a significant immunosuppressive effect.

Effects of pentoxifylline on renal structure after urethral obstruction in rat: A stereological study

Objective

Chronic renal failure due to tubulointerstitial fibrosis is one of complications of lower urinary tract obstruction. Since pentoxifylline is a xanthine derivative that inhibits some inflammatory mediators, we conducted this study to investigate whether pentoxifylline inhibits renal fibrosis in a rat model of partial urethral obstruction (PUO).

Methods

All the rats underwent experimental PUO. Then, the animals were divided randomly into two groups: positive control group and experimental group. The experimental group received pentoxifylline 100 mg/kg per day via oral gavages for 4-weeks. The control group received the same dose of normal saline. After 4-weeks, all the rats underwent left nephrectomy. Kidney volume and weight and fractional and absolute volumes of the glomeruli, tubules, interstitium and vessels were determined with stereological methods. To reduce the workload of reference (kidney) volume estimation, the total kidney volume was determined after estimation of tissue shrinkage on isotropic uniform random histological sections. The total volume (amount) of each renal structure including fibrosis was estimated to avoid the bias conclusion due to relying on volume density alone.

Results

The absolute volume of interstitial fibrosis was lower in the experimental group (PUO with pentoxifylline treatment) (~84%; p ≤0.006) in comparison with the control group (PUO with no treatment).

Conclusion

Pentoxifylline reduces interstitial renal fibrosis after partial urethral obstruction in rats.

Pentoxifylline promotes recovery of erectile function in a rat model of postprostatectomy erectile dysfunction

BACKGROUND

Cavernous nerve (CN) injury during radical prostatectomy (RP) causes CN degeneration and secondary penile fibrosis and smooth muscle cell (SMC) apoptosis. Pentoxifylline (PTX) is a phosphodiesterase inhibitor that further inhibits multiple cytokine pathways involved in nerve degeneration, apoptosis, and fibrosis.

OBJECTIVES

To evaluate whether PTX enhances erectile function in a rat model of CN injury. DESIGN, SETTING AND INTERVENTIONS: Forty male Sprague-Dawley rats underwent CN crush injury and were randomized to oral gavage feeding of phosphate-buffered saline (vehicle) or PTX 25, PTX 50, or PTX 100 mg/kg per day. Ten animals underwent sham surgery and received vehicle treatment. Treatment continued for 28 d, followed by a wash-out period of 72 h. An additional eight rats underwent resection of the major pelvic ganglion (MPG) for tissue culture and examination of direct effects of PTX on neurite sprouting.

MEASUREMENTS

Intracavernous pressure recording on CN electrostimulation, immunohistologic examination of the penis and the CN distal to the injury site, and length of neurite sprouts in MPG culture.

RESULTS

Daily oral gavage feeding of PTX resulted in significant improvement of erectile function compared to vehicle treatment in all treated groups. After treatment with PTX 50 and PTX 100 mg/kg per day, the expression of neuronal nitric oxide synthase in the dorsal penile nerve was significantly higher than in vehicle-treated rats. Furthermore, PTX treatment prevented collagen deposition and SMC loss in the corpus cavernosum. In the CN, signs of Wallerian degeneration were ameliorated by PTX treatment. MPG culture in medium containing PTX resulted in a significant increase of neurite length.

CONCLUSIONS

PTX treatment following CN injury in rats improved erectile recovery, enhanced nerve regeneration, and preserved the corpus cavernosum microarchitecture. The clinical availability of this compound merits application in penile rehabilitation studies following RP in the near future.

Principal component analysis of HPLC retention data and molecular modeling structural parameters of cardiovascular system drugs in view of their pharmacological activity

Evaluation of relationships between molecular modeling structural parameters and high-performance liquid chromatography (HPLC) retention data of 11 cardiovascular system drugs by principal component analysis (PCA) in relation to their pharmacological activity was performed. The six retention data parameters were determined on three different HPLC columns (Nucleosil C18 AB with octadecylsilica stationary phase, IAM PC C10/C3 with chemically bounded phosphatidylcholine, and Nucleosil 100-5 OH with chemically bounded propanodiole), and using isocratically acetonitrile: Britton-Robinson buffer as the mobile phase. Additionally, molecular modeling studies were performed with the use of HyperChem software and MM+ molecular mechanics with the semi-empirical AM1 method deriving 20 structural descriptors. Factor analysis obtained with the use of various sets of parameters: structural parameters, HPLC retention data, and all 26 considered parameters, led to the extraction of two main factors. The first principal component (factor 1) accounted for 44–57% of the variance in the data. The second principal component (factor 2) explained 29–33% of data variance. Moreover, the total data variance explained by the first two factors was at the level of 73–90%. More importantly, the PCA analysis of the HPLC retention data and structural parameters allows the segregation of circulatory system drugs according to their pharmacological (cardiovascular) properties as shown by the distribution of the individual drugs on the plane determined by the two principal components (factors 1 and 2).

Targeting TNF for Treatment of Cancer and Autoimmunity

Tumor necrosis factor-alpha (TNF-alpha) was first isolated two decades ago as a macrophageproduced protein that can effectively kill tumor cells. TNF-alpha is also an essential component of the immune system and is required for hematopoiesis, for protection from bacterial infection and for immune cell-mediated cytotoxicity. Extensive research, however, has revealed that TNF-alpha is one of the major players in tumor initiation, proliferation, invasion, angiogenesis and metastasis. The proinflammatory activities link TNF-alpha with a wide variety of autoimmune diseases, including psoriasis, inflammatory bowel disease, rheumatoid arthritis, systemic sclerosis, systemic lupus erythematosus, multiple sclerosis, diabetes and ankylosing spondylitis. Systemic inhibitors of TNF such as etanercept (Enbrel) (a soluble TNF receptor) and infliximab (Remicade) and adalimumab (Humira) (anti-TNF antibodies) have been approved for the treatment inflammatory bowel disease, psoriasis and rheumatoid arthritis. These drugs, however, exhibit severe side effects and are expensive. Hence orally active blockers of TNF-alpha that are safe, efficacious and inexpensive are urgently needed. Numerous products from fruits, vegetable and traditional medicinal plants have been described which can suppress TNF expression and TNF signaling but their clinical potential is yet uncertain.

Pentoxifylline does not decrease short-term mortality but does reduce complications in patients with advanced cirrhosis

BACKGROUND & AIMS

Pentoxifylline, an inhibitor of tumor necrosis factor-alpha, is given to patients with liver diseases, but its effects in patients with advanced cirrhosis are unknown. We performed a randomized, placebo-controlled, double-blind trial of its effects in patients with cirrhosis.

METHODS

A total of 335 patients with cirrhosis (Child-Pugh class C) were assigned to groups given either pentoxifylline (400 mg, orally, 3 times daily; n = 164) or placebo (n = 171) for 6 months. The primary end point was mortality at 2 months. Secondary end points were mortality at 6 months and development of liver-related complications.

RESULTS

By 2 months, 28 patients in the pentoxifylline group (16.5%) and 31 in the placebo group (18.2%) had died (P = .84). At 6 months, 50 patients in the pentoxifylline group (30.0%) and 54 in the placebo group (31.5%) had died (P = .75). The proportions of patients without complications (eg, bacterial infection, renal insufficiency, hepatic encephalopathy, or gastrointestinal hemorrhage) were higher in the pentoxifylline group than in the placebo group at 2 months (78.6% vs 63.4%; P = .006) and 6 months (66.8% vs 49.7%; P = .002). The probability of survival without complications was higher in the pentoxifylline group than in the placebo group at 2 and 6 months (P = .04). In multivariate analysis, the factors associated with death were age, the Model for End-Stage Liver Disease score, and presence of early-stage carcinoma. Treatment with pentoxifylline was the only factor associated with liver-related complications.

CONCLUSIONS

Although pentoxifylline does not decrease short-term mortality in patients with advanced cirrhosis, it does reduce the risk of complications.

Pentoxifylline in ischemia-induced acute kidney injury in rats

Ischemia is an important cause of acute kidney injury (AKI). Pentoxifylline has been shown to improve tissue oxygenation and endothelial function and inhibit proinflammatory cytokine production. The aim of this study was to evaluate a possible renal protective effect of pentoxifylline against ischemia by measuring mitochondrial respiratory metabolism as an index of cell damage. Rats were submitted to right nephrectomy. The left kidney was submitted to ischemia by clamping the renal artery for 45 minutes. Immediately after release of the clamp, 1 mL of a solution containing 20 mg of pentoxifylline/mL was injected intravenously, while a control group received 1 mL of normal saline intravenously. Five minutes after the injection, the left kidney was removed, homogenized, and subjected to refrigerated differential centrifugation. Mitochondrial respiratory metabolism was measured polarographically. The mitochondria isolated from the kidneys of saline-treated rats had an endogenous respiration of 9.20 +/- 1.0 etamol O(2)/mg protein/min compared to 8.9 +/- 1.4 etamol O(2)/mg protein/min in the pentoxifylline-treated rats (p > 0.05). When stimulated by sodium succinate, the respiratory metabolism increased in a similar fashion in both groups of animals: 17.9 +/- 2.3 and 18.1 +/- 2.1 etamol O(2)/mg protein/min in the untreated and pentoxifylline-treated groups, respectively (p > 0.05). In the present study, pentoxifylline was not found to exert any protective effect on the kidney. It is possible that at the time of pentoxifylline administration, the mitochondria had already been damaged by the process of ischemia, and its effect may have been insufficient to reverse cell damage.

Differential activation of spinal microglial and astroglial cells in a mouse model of peripheral neuropathic pain

The pharmacological attenuation of glial activation represents a novel approach for controlling neuropathic pain, but the role of microglial and astroglial cells is not well established. To better understand the potential role of two types of glial cells, microglia and astrocytes, in the pathogenesis of neuropathic pain, we examined markers associated with them by quantitative RT-PCR, western blot and immunohistochemical analyses in the dorsal horn of the lumbar spinal cord 7days after chronic constriction injury (CCI) to the sciatic nerve in mice. The mRNA and protein of microglial cells were labeled with C1q and OX42(CD11b/c), respectively. The mRNA and protein of astrocytes were labeled with GFAP. The RT-PCR results indicated an increase in C1q mRNA that was more pronounced than the increased expression of GFAP mRNA ipsilateral to the injury in the dorsal spinal cord. Similarly, western blot and immunohistochemical analyses demonstrated an ipsilateral upregulation of OX42-positive cells (72 and 20%, respectively) and no or little (8% upregulation) change in GFAP-positive cells in the ipsilateral dorsal lumbar spinal cord. We also found that chronic intraperitoneal injection of the minocycline (microglial inhibitor) and pentoxifylline (cytokine inhibitor) attenuated CCI-induced activation of microglia, and both, but not fluorocitrate (astroglial inhibitor), diminished neuropathic pain symptoms and tactile and cold sensitivity. Our findings indicate that spinal microglia are more activated than astrocytes in peripheral injury-induced neuropathic pain. These findings implicate a glial regulation of the pain response and suggest that pharmacologically targeting microglia could effectively prevent clinical pain syndromes in programmed and/or anticipated injury.

Protein array technology to investigate cytokine production by monocytes from patients with advanced alcoholic cirrhosis: An ex vivo pilot study

AIM

In patients with advanced cirrhosis, little is known about the ability of peripheral blood monocytes to spontaneously produce signaling proteins such as cytokines. The aim of this ex vivo study was to evaluate cytokine production under baseline conditions and after stimulation by lipopolysaccharide (LPS), a toll-like receptor (TLR) agonist.

METHODS

Peripheral blood monocytes were isolated from patients with advanced alcoholic cirrhosis (without ongoing bacterial infections) and normal subjects. Cells were left unstimulated or were stimulated with LPS. The abundance of 24 cytokines was measured using a filter-based, arrayed sandwich enzyme-linked immunosorbent assay (ELISA) in the supernatant of cultured monocytes.

RESULTS

Cirrhotic monocytes spontaneously produced six proteins (TNF-alpha, IL-6, IL-8, MCP-1, RANTES and Gro), whereas normal monocytes produced only small amounts of IL-8 and RANTES. Analyses with the online gene set analysis toolkit WebGestalt (http://bioinfo.vanderbilt.edu/webgestalt) found enrichment for the six proteins in the human gene ontology subcategory (http://www.geneontology.org), Kyoto Encyclopedia of Genes and Genome pathways (http://www.genome.ad.jp/kegg/) and BioCarta pathways (http://www.biocarta.com/genes/index.asp) consistent with a proinflammatory phenotype of cirrhotic monocytes resulting from activated TLR signaling. Interestingly, LPS-elicited TLR engagement further increased the production of the six proteins and did not induce the secretion of any others, in particular the anti-inflammatory cytokine IL-10. LPS-stimulated normal monocytes produced TNF-alpha, IL-6, IL-8, MCP-1, RANTES, Gro and IL-10.

CONCLUSION

In patients with advanced cirrhosis, peripheral blood monocytes spontaneously produce proinflammatory cytokines, presumably in response to unrestricted TLR signaling.

Randomized study of the effect of pentoxifylline or octreotide on serum levels of TNF-alpha and IL-6 after endoscopic retrograde cholangiopancreatography

OBJECTIVES

To study the effect of pentoxifylline and octreotide administration on serum levels of TNF-alpha and IL-6, in patients who underwent endoscopic retrograde cholangiopancreatography (ERCP), whether they developed pancreatitis or not.

METHODS

Out of 590 patients undergoing ERCP, 30 who developed pancreatitis and 25 who did not (controls) were enrolled. Pentoxifylline was given to 23 patients (15 with and eight without pancreatitis) and octreotide to 19 patients (nine with and 10 without pancreatitis, respectively). Thirteen patients did not receive any preventive medication (six with and seven without pancreatitis, respectively). Blood samples were collected at baseline, 6 and 24 h after ERCP.

RESULTS

IL-6 increased significantly in patients with pancreatitis at the 6 h (4.2 pg/ml SD: 5.8) and at the 24 h (6.6 pg/ml SD: 9.8) compared with patients without pancreatitis at the 6 h (2.1 pg/ml SD: 3.6) and 24 h (1.9 pg/ml SD: 2.5) (P < 0.01). No significant difference in the values of TNF-alpha and IL-6 obtained among the three study groups in patients with or without pancreatitis was observed. TNF-alpha levels at the 24 h were lower than baseline in patients with pancreatitis who received octreotide (P = 0.04).

CONCLUSION

IL-6 increased in the first 24 h of post-ERCP pancreatitis. Pentoxifylline and octreotide cannot prevent IL-6 elevation but octreotide reduces TNF-alpha levels, which may have an impact on the severity of post-ERCP pancreatitis.

Microbial transformation of hydroxy metabolites of 1-oxohexyl derivatives of theobromine by Cunninghamella echinulata NRRL 1384

AIM

The biotransformation of pentoxifylline (PTX), propentofylline (PPT) and their racemic hydroxy metabolites ((+/-)-OHPTX and (+/-)-OHPPT) by using the fungus Cunninghamella echinulata NRRL 1384.

METHODS AND RESULTS

A fungus Cunninghamella echinulata NRRL 1384 was used to catalyse the (S)-selective oxidation of the racemic hydroxy metabolites: (+/-)-OHPTX and (+/-)-OHPPT and for reduction of PTX and PPT. The first oxidation step appears to be selective and relatively fast while the second reduction step is slower and more selective with PTX. Modifications involving supplementing the bioconversion with glucose give yields and enantiomeric excess (ee) values similar to those obtained without glucose.

CONCLUSIONS

The bioconversion of (+/-)-OHPTX gave an (R)-enantiomer (LSF-lisofylline) with a higher enantiopurity (maximum approximately 93% ee) compared to the bioconversion of (+/-)-OHPPT, when the maximum ee value for (R)-OHPPT was recorded at 83%.

SIGNIFICANCE AND IMPACT OF THE STUDY

The conversion of (+/-)-OHPTX and (+/-)-OHPPT using Cunninghamella echinulata can be recognized as a process, which may be recommended as an alternative to the methods used to obtain (R)-OHPTX and (R)-OHPPT.

Cardiac cachexia: a systematic overview

Cardiac cachexia as a terminal stage of chronic heart failure carries a poor prognosis. The definition of this clinical syndrome has been a matter of debate in recent years. This review describes the ongoing discussion about this issue and the complex pathophysiology of cardiac cachexia and chronic heart failure with particular focus on immunological, metabolic, and hormonal aspects at the intracellular and extracellular level. These include regulators such as neuropeptide Y, leptin, melanocortins, ghrelin, growth hormone, and insulin. The regulation of feeding is discussed as are nutritional aspects in the treatment of the disease. The mechanisms of wasting in different body compartments are described. Moreover, we discuss several therapeutic approaches. These include appetite stimulants like megestrol acetate, medroxyprogesterone acetate, and cannabinoids. Other drug classes of interest comprise angiotensin-converting enzyme inhibitors, beta-blockers, anabolic steroids, beta-adrenergic agonists, anti-inflammatory substances, statins, thalidomide, proteasome inhibitors, and pentoxifylline.

Heme oxygenase-1 and the vascular bed: from molecular mechanisms to therapeutic opportunities

Heme oxygenase-1, an enzyme degrading heme to carbon monoxide, iron, and biliverdin, has been recognized as playing a crucial role in cellular defense against stressful conditions, not only related to heme release. HO-1 protects endothelial cells from apoptosis, is involved in blood-vessel relaxation regulating vascular tone, attenuates inflammatory response in the vessel wall, and participates in blood-vessel formation by means of angiogenesis and vasculogenesis. The latter functions link HO-1 not only to cardiovascular ischemia but also to many other conditions that, like development, wound healing, or cancer, are dependent on neovascularization. The aim of this comprehensive review is to address the mechanisms of HO-1 regulation and function in cardiovascular physiology and pathology and to demonstrate some possible applications of the vast knowledge generated so far. Recent data provide powerful evidence for the involvement of HO-1 in the therapeutic effect of drugs used in cardiovascular diseases. Novel studies open the possibilities of application of HO-1 for gene and cell therapy. Therefore, research in forthcoming years should help to elucidate both the real role of HO-1 in the effect of drugs and the clinical feasibility of HO-1-based cell and gene therapy, creating the effective therapeutic avenues for this refined antioxidant system.

Pentoxifylline attenuates nociceptive sensitization and cytokine expression in a tibia fracture rat model of complex regional pain syndrome

BACKGROUND

Tibia fracture in rats evokes chronic hindpaw warmth, edema, allodynia, and regional osteopenia, a syndrome resembling complex regional pain syndrome (CRPS). Previous studies suggest that the pathogenesis of some of these changes involves an exaggerated regional inflammatory response to injury and we postulated that inflammatory cytokines contribute to the development of CRPS-like changes after fracture.

METHODS

The distal tibia was fractured and the hindlimb casted for 4 weeks. The rats were given drinking water with or without the cytokine inhibitor pentoxifylline (PTX) starting the day before fracture and continuing for 4 weeks, after which time the cast was removed and multiple assays were performed in the hindpaw. PCR and immunoassays were used to evaluate changes in cytokine expression. Bilateral hindpaw thickness, temperature, and nociceptive thresholds were determined, and bone microarchitecture was measured by microcomputed tomography (microCT).

RESULTS

Tibia fracture chronically up-regulated TNFalpha, IL-1beta and IL-6 mRNA and protein levels in hindpaw skin and PTX treatment significantly reduced the mRNA expression and cytokine protein levels for all these cytokines. PTX inhibited the nociceptive sensitization and some vascular changes, but had insignificant effects on most of the bone-related parameters measured in these studies. Immunostaining of hindpaw skin was negative for immunocyte infiltration at 4 weeks post-fracture.

CONCLUSIONS

These results suggest that pro-inflammatory cytokines contribute to the nociceptive and vascular sequelae of fracture and that PTX treatment can reverse these CRPS-like changes.

Treating the chronic wound: A practical approach to the care of nonhealing wounds and wound care dressings

Chronic wounds are a major healthcare problem costing the United States billions of dollars a year. The American Academy of Dermatology has underscored the significance of wound care in dermatological practice. It is critical for all dermatologists to understand the elements of diagnosis and therapy. We emphasize major aspects of diagnosis and present a simple classification of wound dressings with guidelines for usage and relative cost data.

LEARNING OBJECTIVE

After completing this learning activity, participants should be able to diagnose common types of chronic wounds, formulate a therapeutic plan, and describe the major classes of topical therapies and dressings for the chronic wound.

Effect of TNF-alpha inhibition on urinary albumin excretion in experimental diabetic rats

The objective is to assess the effect of TNF-alpha inhibition on urinary albumin excretion in experimental diabetic rats. Male Wistar rats, 8-week-old, were categorized into four groups, which were the control (n = 9), diabetes (n = 9), infliximab-treated diabetes (n = 10), and FR167653-treated diabetes (n = 9) groups. Diabetes was induced by intraperitoneal injection of STZ (40 mg/kg). Thereafter, infliximab was injected intraperitoneally once a month (5.5 mg/kg) and FR167653 was administered orally by mixing with the rat chow (0.08%). The effects of infliximab and FR167653 on urinary albumin excretion were observed for 12 weeks. Body weight, blood sugar, 24-h urinary TNF-alpha, and 24-h urinary albumin/creatinine ratio (Ualb/Ucr) levels were determined at 1, 4, 8, and 12 weeks after the STZ-injection. Treatment of rats with STZ caused a significant loss of body weight, as well as polyuria and hyperglycemia within 1 week, while the urinary excretions of albumin and TNF-alpha were increased. Neither infliximab nor FR167653 affected body weight or blood sugar levels, whereas both decreased urinary albumin excretion, together with a modest decrease in the urinary excretion of TNF-alpha. These results suggest a role of TNF-alpha in the pathogenesis of diabetic nephropathy and show that TNF-alpha inhibition is a potential therapeutic strategy.

A randomized controlled trial of pentoxifylline for the prevention of post-ERCP pancreatitis

BACKGROUND

Pentoxifylline can ameliorate pancreatitis in animal models because of its anti-tumor necrosis factor properties.

OBJECTIVE

Our purpose was to study the safety and efficacy of pentoxifylline in the prevention of post-ERCP pancreatitis.

DESIGN

Patients due to undergo ERCP for various indications were randomized to receive pentoxifylline 400 mg orally 3 times, beginning the day before ERCP (2 and 10 pm) until the night after the procedure (6 am and 2 and 10 pm) or to receive no preventive medication. Serum amylase values were determined before and 6 and 24 hours after ERCP. Diagnosis and grading of the severity of complications was performed according to consensus criteria.

PATIENTS

One hundred fifty-eight patients received pentoxifylline (group A) and 162 had no medication (group B). The groups were similar in distributions of sex, biliary sphincterotomy, pancreatography, pancreatic duct cannulations, stone extraction, stent placement, and presence of periampullary diverticulum. Group A patients were younger (mean age 63 vs 68 years, P<.05) and biliary colic was a more frequent indication (30 vs 12, P<.05).

RESULTS

Nine (5.6%) patients in group A and 5 (3%) in group B had pancreatitis (2 and 1 severe, respectively; P=.28). Serum amylase values were similar in baseline and 6- and 24-hour samples. Two (1.2%) patients in group A and 7 (4.3%) in group B had hemorrhage.

LIMITATIONS

This was not a double-blind trial.

CONCLUSIONS

In this study pentoxifylline did not protect against post-ERCP pancreatitis or hyperamylasemia.

Amelioration of steatohepatitis with pentoxifylline in a novel nonalcoholic steatohepatitis model induced by high-fat diet

We sought to evaluate the effects of pentoxifylline (PTX) on steatohepatitis in a novel experimental nonalcoholic steatohepatitis (NASH) model induced by a high-fat diet (HFD). Thirty-three male Sprague-Dawley rats were randomly divided into 3 groups. The first group received only standard rat diet (control group); groups 2 (placebo group) and 3 were given HFD, ad libitum. After week 4, 0.5 mL of physiologic serum was injected subcutaneously to the placebo group and 50 mg/kg/d PTX was given intraperitoneally to the third group (group PTX). After 6 weeks all rats were humanely killed. Serum biochemistry, tumor necrosis factor-alpha (TNF-alpha), plasma, and liver tissue malondialdehyde (MDA) were analyzed. Histopathologically, steatosis, ballooning degeneration, inflammation, and fibrosis were determined. Aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels, plasma and liver tissue MDA, and plasma TNF-alpha levels were significantly higher in placebo group than in the control group. Tumor growth factor-beta levels, however, were comparable in the placebo and control groups. On histopathologic examination, steatosis, inflammatory cells per square millimeter, and ballooning degeneration were significantly higher in the placebo group than in the control group. No fibrosis or Mallory bodies were found in the placebo group. AST, ALT, plasma and liver tissue MDA, and plasma TNF-alpha levels were significantly lower in PTX group compared to the placebo group. Histopathologically, steatosis, mean number of inflammatory cells/mm(2) and ballooning degeneration in PTX group were also significantly lower than in the placebo group. In conclusion, PTX strikingly ameliorates steatohepatitis in this novel NASH model not only by inhibiting the TNF-alpha but also suppressing the oxidative stress markers.

In vivo altered unfolded protein response and apoptosis in livers from lipopolysaccharide-challenged cirrhotic rats

BACKGROUND/AIMS

Endoplasmic reticulum (ER)-related unfolded protein response (UPR) is mediated by PKR-like ER kinase (PERK), ATF6 and IRE1. PERK phosphorylates eukaryotic translation initiation factor-2alpha (eIF2alpha) to attenuate protein synthesis, including in NF-kappaB-dependent antiapoptotic proteins. We hypothesized that an altered UPR in the liver may sensitize cirrhotic livers to LPS-induced, TNFalpha-mediated apoptosis. Thus, we examined in vivo UPR and NF-kappaB activity in livers from cirrhotic and normal LPS-challenged rats.

METHODS

Livers were harvested in rats that did or did not receive LPS.

RESULTS

Under baseline conditions, no UPR was found in normal livers while PERK/eIF2alpha and ATF6 pathways were activated in cirrhotic livers. After LPS, in normal livers, the PERK/eIF2alpha pathway was transiently activated. ATF6 and IRE1 were activated. In cirrhotic livers, the PERK/eIF2alpha pathway remained elevated. ATF6 and IRE1 pathways were altered. LPS-induced, NF-kappaB-dependent antiapoptotic proteins increased in normal livers whereas their expression was blunted at the posttranscriptional level in cirrhotic livers.

CONCLUSIONS

Cirrhotic livers exhibit partial UPR activation in the basal state and full UPR, although altered, after LPS challenge. Sustained eIF2alpha phosphorylation, a hallmark of cirrhotic liver UPR, is associated with a lack of LPS-induced accumulation of NF-kappaB-dependent antiapoptotic proteins which may sensitize cirrhotic livers to LPS/TNFalpha-mediated apoptosis.