Preventive effect of pentoxifylline on acute radiation damage via antioxidant and anti-inflammatory pathways

Prolonged use of pentoxifylline increases the life expectancy of patients with compensated cirrhosis: A 20‑year retrospective study

Liver cirrhosis is a pathology of varied etiology with a high prevalence and mortality, resulting in >1 million mortalities per year. Patients with liver cirrhosis typically have a survival time of 12 years following diagnosis. The treatment for this disease is directed at the complications of cirrhosis; however, to the best of our knowledge, the long-term management of patients with cirrhosis has been scarcely studied. Pentoxifylline (PTX) is a non-selective phosphodiesterase inhibitor with rheological activity and antioxidant, anti-inflammatory and antifibrotic properties. PTX has been used in the treatment of peripheral arterial disease, inflammatory liver diseases and hepatocellular carcinoma with encouraging results. The aim of the present study was to evaluate the effect of PTX use on the survival of patients with compensated cirrhosis. For this purpose, a cross-sectional study was performed at the Gastroenterology and Hepatitis C Department of Dr. Valentín Gómez Farias Hospital (Institute for Security and Social Services for State Workers, Zapopan, Mexico) from June, 1996 to December, 2019. The follow-up time for these patients was 22.6 years (up to the end of the study period). In the present study, 326 patient files were analyzed and 118 patients with the disease were identified, 81 of whom (68.64%) died within 12 years after diagnosis. Of the included patients, 26 received PTX combined with PEG IFN-α-2a plus ribavirin, and 11 received PTX plus propranolol, with a median treatment duration of 20.6±0.8 years. Furthermore, 16 patients (43%) did not develop co-morbidities within this time, and the transition to decompensated cirrhosis was 16.6 years, with a survival time of 20 years. Therefore, the results of the present study suggest that PTX may improve the long-term survival of patients with compensated cirrhosis, rendering PTX a candidate for repurposing in the treatment of hepatic cirrhosis.

Pentoxifylline in patients with ulcerative colitis treated with mesalamine by modulation of IL-6/STAT3, ZO-1, and S1P pathways: a randomized controlled double-blinded study

BACKGROUND

Ulcerative colitis (UC) is an inflammatory bowel disease (IBD) that lasts a long time and has a variety of causes.

AIM

The primary aim of this study was to evaluate pentoxifylline's (PTX) essential function in patients with UC.

METHODS

Fifty-two mild to moderate UC patients who matched the eligibility requirements participated in this clinical study. One gram of mesalamine (t.i.d.) and a placebo were administered to the mesalamine group (n = 26) for a duration of 24 weeks. Mesalamine 1 g t.i.d. and PTX 400 mg two times daily were administered to the PTX group (n = 26) for 24 weeks. A gastroenterologist investigated patients at the start and 6 months after the medication was given to assess disease activity index (DAI) and numeric pain rating scale (NRS). Also, interleukin-6 (IL-6), sphingosine 1 phosphate (S1P), tumor necrosis factor-alpha (TNF-α), and fecal myeloperoxidase (MPO) were measured before and after therapy. Zonula occuldin-1 (ZO-1) and signal transducer and activator of transcription factor-3 (STAT-3) expression was assessed before and after therapy as well as histological assessment. Short Form 36 Health Survey (SF-36), was assessed for each patient before and after 6 months of treatment.

RESULTS

The PTX group showed statistically lower levels of serum SIP, TNF-α, IL-6, faecal MPO, gene expression of STAT-3, and a significant increase of ZO-1 in comparison with the mesalamine group. DAI and NRS significantly decreased whereas SF-36 significantly increased in the PTX group.

CONCLUSION

PTX could alleviate inflammation in patients with UC, so it might be promising adjunctive for patients with UC.

TRIAL REGISTRATION IDENTIFIER

NCT05558761.

Oxidative hemolytic crises in a dog due to fragrance products: clinical insights and treatment approaches

IMPORTANCE

This is the first reported case of fragrance products-induced recurrent oxidative hemolytic anemia in a dog, detailing the successful therapeutic approach employed.

CASE PRESENTATION

A 4-year-old intact female Pomeranian dog presented with brown tongue, pigmenturia, peripheral edema, and vomiting. Blood smears revealed a high count of eccentrocytes and Heinz bodies, along with a precipitous decline in packed cell volume and an increase in blood methemoglobin levels, suggesting an oxidative hemolytic crisis. This clinicopathological pattern recurred several times after the patient returned home. Antioxidants, methylene blue, hyperbaric oxygen (HBO) therapy, and blood transfusion were successfully employed to address recurrent hemolytic anemia; however, oxidative hemolytic crises recurred. After the owner removed exposure to various home remedies and fragrances, the clinical signs and hemolytic crises did not recur.

CONCLUSIONS AND RELEVANCE

Recurring oxidative hemolytic crises should raise suspicions of environmental toxicity, which, although harmless in small quantities to humans, can be devastating to small-breed dogs. In addition to removing the causative agents, methylene blue and other antioxidants, along with HBO, may be beneficial in the acute management of oxidative hemolytic anemia.

A raising dawn of pentoxifylline in management of inflammatory disorders in Covid-19

The existing pandemic viral infection caused by severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) leads to coronavirus disease 2019 (Covid-19). SARS-CoV-2 exploits angiotensin-converting enzyme 2 (ACE2) as an entry-point into affected cells and down-regulation of ACE2 by this virus triggers the release of pro-inflammatory cytokines and up-regulation of angiotensin II. These changes may lead to hypercytokinemia and the development of cytokine storm with the development of acute lung injury and acute respiratory distress syndrome. Different repurposed had been in use in the management of Covid-19, one of these agents is pentoxifylline (PTX) which has anti-inflammatory and antioxidant properties. Therefore, the objective of the present mini-review is to highlight the potential role of PTX in Covid-19 regarding its anti-inflammatory and antioxidant effects. PTX is a non-selective phosphodiesterase inhibitor that increases intracellular cyclic adenosine monophosphate which stimulates protein kinase A and inhibits leukotriene and tumor necrosis factor. PTX has antiviral, anti-inflammatory and immunomodulatory effects, thus it may attenuate SARS-CoV-2-induced hyperinflammation and related complications. As well, PTX can reduce hyper-viscosity and coagulopathy in Covid-19 through increasing red blood cell deformability and inhibition of platelet aggregations. In conclusion, PTX is a non-selective phosphodiesterase drug, that has anti-inflammatory and antioxidant effects thereby can reduce SARS-CoV-2 infection-hyperinflammation and oxidative stress. Besides, PTX improves red blood cells (RBCs) deformability and reduces blood viscosity so can mitigate Covid-19-induced hyper-viscosity and RBCs hyper-aggregation which is linked with the development of coagulopathy. Taken together, PTX seems to be an effective agent against Covid-19 severity.

Repurposing Pharmaceuticals Previously Approved by Regulatory Agencies to Medically Counter Injuries Arising Either Early or Late Following Radiation Exposure

The increasing risks of radiological or nuclear attacks or associated accidents have served to renew interest in developing radiation medical countermeasures. The development of prospective countermeasures and the subsequent gain of Food and Drug Administration (FDA) approval are invariably time consuming and expensive processes, especially in terms of generating essential human data. Due to the limited resources for drug development and the need for expedited drug approval, drug developers have turned, in part, to the strategy of repurposing agents for which safety and clinical data are already available. Approval of drugs that are already in clinical use for one indication and are being repurposed for another indication is inherently faster and more cost effective than for new agents that lack regulatory approval of any sort. There are four known growth factors which have been repurposed in the recent past as radiomitigators following the FDA Animal Rule: Neupogen, Neulasta, Leukine, and Nplate. These four drugs were in clinic for several decades for other indications and were repurposed. A large number of additional agents approved by various regulatory authorities for given indications are currently under investigation for dual use for acute radiation syndrome or for delayed pathological effects of acute radiation exposure. The process of drug repurposing, however, is not without its own set of challenges and limitations.

A randomized double-blinded placebo-controlled clinical trial on protective effects of pentoxifylline on gentamicin nephrotoxicity in infectious patients

BACKGROUND AND OBJECTIVE

Renal toxicity has limited gentamicin use in clinical practice. The aim of the present clinical trial was to assess the possible nephroprotective effects of pentoxifylline (PTX) against gentamicin nephrotoxicity.

MATERIALS AND METHODS

A multicenter, randomized, double-blind, placebo-controlled clinical trial was conducted on patients who had the indication for systemic gentamicin for at least 7 days. Sixty people were selected and randomly assigned. For patients in the intervention and control groups, 400 mg PTX sustained release tablet and placebo were given orally three times daily, respectively. Demographic, clinical, laboratory, and therapeutic information of patients were recorded. malondialdehyde (MDA) and tumor necrosis factor-alpha (TNF-α) levels in serum were measured on days 0 and 7.

RESULTS

The incidence of nephrotoxicity in the placebo group was 19.6 times higher than that in the PTX group (OR = 19.6, 95%CI = 3.08-114.32; P value = 0.001). The mean ± SD time onset of ATN was 4.00 ± 2.32 and 5.58 ± 1.59 days in PTX and placebo recipients, respectively (P value < 0.001). No significant differences were observed for hypokalemia, hypomagnesemia, potassium and magnesium wasting between the two groups. The mean ± SD levels of serum MDA and TNF-α at day 7 were significantly lower in the PTX compared to those in the placebo group (P value < 0.001 for both indexes).

CONCLUSION

The co-administration of 400 mg PTX orally three times daily along with gentamicin was both well-tolerated and effective in preventing the nephrotoxicity of gentamicin in patients with different infectious diseases.

Pentoxifylline Can Reduce the Inflammation Caused by LPS after Inhibiting Autophagy in RAW264.7 Macrophage Cells

Pentoxifylline (PTX), as a methylxanthine derivative and nonspecific phosphodiesterase inhibitor, has the characteristics of anti-inflammatory and partial inflammatory process inhibition. However, the regulatory effect of PTX on inflammatory cytokines is unclear. Autophagy can regulate the activation of inflammasomes and then inhibit inflammation as previously described. Our study attempts to explore the relationship between autophagy and PTX-mediated regulation of inflammasome suppression. Macrophage-like RAW264.7 cells were studied as the in vitro macrophage model. We investigated the anti-inflammatory effect caused by PTX with time and dose response against the LPS-induced inflammatory factors (TNF-α, IL-1β). Western blot detected the levels of autophagy-related proteins Beclin-1 and LC3, as well as the signal pathways of AMPK and p-AMPK. Fluorescence microscope and transmission electron microscope were used to observe the autophagy bodies in cells influenced by PTX. The autophagy in cells inhibited by PTX exhibited dose- and time-dependent effects, and PTX alleviated LPS-induced inflammation caused by retarded autophagy. Furthermore, in RAW264.7 macrophage cells, our data indicated that AMPK signaling perhaps functioned importantly in repressed autophagy. In addition, in RAW264.7 macrophages, our data suggested that AMPK signaling might play an important role in inhibiting autophagy during the process of PTX ameliorating LPS-mediated inflammation.

Pentoxifylline Attenuates Arsenic Trioxide-Induced Cardiac Oxidative Damage in Mice

This study was undertaken to evaluate the therapeutic potential effect of pentoxifylline (PTX) against arsenic trioxide (ATO)-induced cardiac oxidative damage in mice. Thirty-six male albino mice were divided into six groups and treated intraperitoneally with normal saline (group 1), ATO (5 mg/kg; group 2), PTX (100 mg/kg; group 3), and different doses of PTX (25, 50, and 100 mg/kg; groups 4, 5, and 6, respectively) with ATO. After four weeks, the blood sample was collected for biochemical experiments. In addition, cardiac tissue was removed for assessment of oxidative stress markers and histopathological changes (such as hemorrhage, necrosis, infiltration of inflammatory cells, and myocardial degeneration). The findings showed that ATO caused a significant raise in serum biochemical markers such as lactate dehydrogenase (LDH), creatine phosphokinase (CPK) and troponin-I (cTnI), glucose, total cholesterol (TC), and triglyceride (TG) levels. In addition to histopathological changes in cardiac tissue, ATO led to the significant increase in cardiac lipid peroxidation (LPO) and nitric oxide (NO); remarkable decrease in the activity of cardiac antioxidant enzymes such as catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx); and the depletion of the total antioxidant capacity (TAC) and total thiol groups (TTGs). PTX was able to reduce the increased levels of serum cardiac markers (LDH, CPK, cTnI, TC, and TG), cardiac LPO, and improve antioxidant markers (TAC, TTGs, CAT, SOD, and GPx) alongside histopathologic changes. However, no significant changes were observed in elevated serum glucose and cardiac NO levels. In conclusion, the current study showed the potential therapeutic effect of PTX in the prevention of ATO-induced cardiotoxicity via reversing the oxidative stress.

Coenzyme Q10 attenuates inflammation and fibrosis implicated in radiation enteropathy through suppression of NF-kB/TGF-β/MMP-9 pathways

Radiation enteropathy is one the most common clinical issue for patients receiving radiotherapy for abdominal/pelvic tumors which severely affect the quality of life of cancer patients due to dysplastic lesions (ischemia, ulcer, or fibrosis) that aggravate the radiation damage. Herein, this study demonstrated the prophylactic role of coenzyme Q10 (CoQ10), a powerful antioxidant, against radiotherapy-induced gastrointestinal injury. Male Sprague Dawley rats were divided into four groups: group 1 was defined as control, and group 2 was the irradiated group. Group 3 and 4 were CoQ10 control and radiation plus CoQ10 groups, respectively. CoQ10 (10 mg/kg) was orally administered for 10 days before 10 Gy whole-body radiation and was continued for 4 days post-irradiation. CoQ10 administration protected rats delivered a lethal dose of ϒ-radiation from changes in crypt-villus structures and promoted regeneration of the intestinal epithelium. CoQ10 attenuated radiation-induced oxidative stress by decreasing lipid peroxidation and increasing the antioxidant enzyme catalase activity and reduced glutathione level. CoQ10 also counteracts inflammatory response mediated after radiation exposure through downregulating intestinal NF-ĸB expression which subsequently decreased the level of inflammatory cytokine IL-6 and the expression of COX-2. Radiation-induced intestinal fibrosis confirmed via Masson's trichrome staining occurred through upregulating transforming growth factor (TGF)-β1 and matrix metalloproteinase (MMP)-9 expression, while CoQ10 administration significantly diminishes these effects which further confirmed the anti-fibrotic property of CoQ10. Therefore, CoQ10 is a promising radioprotector that could prevent intestinal complications and enhance the therapeutic ratio of radiotherapy in patients with pelvic tumors through suppressing the NF-kB/TGF-β1/MMP-9 signaling pathway.

Metabolomic studies in tissues of mice treated with amifostine and exposed to gamma-radiation

Although multiple radioprotectors are currently being investigated preclinically for efficacy and safety, few studies have investigated concomitant metabolic changes. This study examines the effects of amifostine on the metabolic profiles in tissues of mice exposed to cobalt-60 total-body gamma-radiation. Global metabolomic and lipidomic changes were analyzed using ultra-performance liquid chromatography (UPLC) quadrupole time-of-flight mass spectrometry (QTOF-MS) in bone marrow, jejunum, and lung samples of amifostine-treated and saline-treated control mice. Results demonstrate that radiation exposure leads to tissue specific metabolic responses that were corrected in part by treatment with amifostine in a drug-dose dependent manner. Bone marrow exhibited robust responses to radiation and was also highly responsive to protective effects of amifostine, while jejunum and lung showed only modest changes. Treatment with amifostine at 200 mg/kg prior to irradiation seemed to impart maximum survival benefit, while the lower dose of 50 mg/kg offered only limited survival benefit. These findings show that the administration of amifostine causes metabolic shifts that would provide an overall benefit to radiation injury and underscore the utility of metabolomics and lipidomics to determine the underlying physiological mechanisms involved in the radioprotective efficacy of amifostine. This approach may be helpful in identifying biomarkers for radioprotective efficacy of amifostine and other countermeasures under development.

Intestinal injury can be effectively prevented by Dunaliella salina in gamma irradiated rats

Dunaliella salina (D. salina) is one of the most common microalgae that is used as human food. It is isolated from the salty lakes in El-Fayoum and Lake of Bardawil-Sinai in Egypt and can withstand very high concentrations of salt: The potentiality of D. salina, a unicellular biflagellate green alga to protect against intestinal injury induced after radiation exposure was studied. D. salina was given orally in doses of 100 and 200 mg/kg to male Wistar rats for 5 days before exposure to 6 Gray (Gy) gamma radiation and continued for a further two days. Rats were sacrificed 24 h later and intestinal segments were dissected out. One segment was examined histologically and another was used to prepare homogenates to assess relevant biochemical parameters reflecting intestinal injury. Radiation exposure led to a rise in the histological damage score, an increase in tissue tumor necrosis factor (TNF-α), interleukin (IL-1β) and thiobarbituric acid reactive substances (TBARS) but a reduction in tissue reduced glutathione (GSH) and in serum citrulline. Pretreatment with either dose of D. salina effectively reduced the severity of intestinal mucositis induced by gamma radiation.

Rheinic acid ameliorates radiation-induced acute enteritis in rats through PPAR-γ/NF-κB

BACKGROUND

Acute radiation enteritis (ARE), a common complication of intestinal caused by abdominal and pelvic radiation therapy. Rheinic acid is a major active ingredient derived from Rhubarb. Rhubarb could suppress inflammation, tumor, fibrosis oxidative damage. However, RA as the main active component and extract monomer of Rhubarb, the pharmacological activity and the underlying molecular mechanism on various diseases has not yet been revealed.

OBJECTIVE

To determine the potential role of rheinic acid (RA) in ameliorating inflammation of rats with acute radiation enteritis (ARE), and explore the underlying mechanism.

METHODS

ARE rat model was established by irradiated with single-dose 10 Gy X-rays at a rate of 0.62 Gy/min to the abdomen. The rats were executed after orally administered with Rheinic acid 7 days and used in the subsequent experiments. Body weight, fecal characteristics and bloody of rats were used to assess the disease activity index. Histological analysis of the jejunum and colon were evaluated using H&E staining. The pro-inflammatory cytokines levels were measured by immunohistochemistry and ELISA. The levels of nitric oxide (NO), malondialdehyde (MDA), superoxide dismutase (SOD) and glutathione (GSH) were also determined. The mRNA and protein expression were examined by real-time polymerase chain reaction (qRT-PCR) and western blot, respectively.

RESULTS

Rheinic acid promoted intestinal functional recovery, and ameliorated intestinal damage and bloody stool in ARE rats. Rheinic acid strongly decreased the levels of tumor necrosis factor-α, interleukin-1, interleukin-6, NO, and MDA, whereas increased levels of anti-oxidants, SOD and GSH. Moreover, the expression of apoptosis-related proteins, cleaved caspase-3 and cleaved poly (ADP-ribose) polymerase (PARP), were decreased with RA treatment. Further study indicated that PPAR-γ was activated and thereby NF-κB and p38 MAPK signaling pathway were suppressed after rheinic acid treatment.

CONCLUSION

Rheinic acid could ameliorate acute radiation enteritis and the underlying molecular mechanism is, at least partially, through PPAR-γ/NF-κB and p38 MAPK/JNK pathways.

Purified PEGylated human glucagon-like peptide-2 reduces the severity of irradiation-induced acute radiation enteritis in rats

Radiation-induced acute intestinal injury after abdominal and pelvic irradiation is a common and serious problem in the clinical setting. Glucagon-like peptide-2 (GLP-2), a 33-amino acid peptide, exerts diverse effects related to the regulation of gastrointestinal growth and function. However, GLP-2 is relatively unstable in vivo. The aim of the present study was to improve GLP-2 stability in vivo and to evaluate its therapeutic effect on acute radiation enteritis. We generated long-lasting intestinal protection peptides by conjugating human GLP-2 (hGLP-2) peptides to polyethyleneglycol (PEG) to produce mPEGylation hGLP-2 (Mono-PEG-hGLP-2) through an enzymatic site-specific transglutamination reaction. Mono-PEG-hGLP-2 synthesized under optimal reaction conditions and separated by one-step ion-exchange chromatography was found to be resistant to degradation in vitro. Pretreatment with Mono-PEG-hGLP-2 reduced the severity of radiation-induced intestinal injury, oxidative stress, and the expression of NF-κB in rats with irradiation-induced acute radiation enteritis. The enhanced biological potency of Mono-PEG-hGLP-2 highlights its potential as a therapeutic agent for intestinal diseases.

A review of radiation countermeasures focusing on injury-specific medicinals and regulatory approval status: part III. Countermeasures under early stages of development along with 'standard of care' medicinal and procedures not requiring regulatory approval for use

PURPOSE

Terrorist attacks, with their intent to maximize psychological and economic damage as well as inflicting sickness and death on given targeted populations, are an ever-growing worldwide concern in government and public sectors as they become more frequent, violent, and sensational. If given the chance, it is likely that terrorists will use radiological or nuclear weapons. To thwart these sinister efforts, both physical and medical countermeasures against these weapons are currently being researched and developed so that they can be utilized by the first responders, military, and medical providers alike. This is the third article of a three-part series in which we have reviewed additional radiation countermeasures that are currently under early preclinical phases of development using largely animal models and have listed and discussed clinical support measures, including agents used for radiation-induced emesis, as well as countermeasures not requiring Food and Drug Administration approval.

CONCLUSIONS

Despite the significant progress that has been made in this area during the last several years, additional effort is needed in order to push promising new agents, currently under development, through the regulatory pipeline. This pipeline for new promising drugs appears to be unreasonably slow and cumbersome; possible reasons for this inefficiency are briefly discussed. Significant and continued effort needs to be afforded to this research and development area, as to date, there is no approved radioprotector that can be administered prior to high dose radiation exposure. This represents a very significant, unmet medical need and a significant security issue. A large number of agents with potential to interact with different biological targets are under development. In the next few years, several additional radiation countermeasures will likely receive Food and Drug Administration approval, increasing treatment options for victims exposed to unwanted ionizing irradiation.

Protection against Radiotherapy-Induced Toxicity

Radiation therapy is a highly utilized therapy in the treatment of malignancies with up to 60% of cancer patients receiving radiation therapy as a part of their treatment regimen. Radiation therapy does, however, cause a wide range of adverse effects that can be severe and cause permanent damage to the patient. In an attempt to minimize these effects, a small number of compounds have been identified and are in use clinically for the prevention and treatment of radiation associated toxicities. Furthermore, there are a number of emerging therapies being developed for use as agents that protect against radiation-induced toxicities. The aim of this review was to evaluate and summarise the evidence that exists for both the known radioprotectant agents and the agents that show promise as future radioprotectant agents.

Propolis aqueous extract preserves functional integrity of murine intestinal mucosa after exposure to ionizing radiation

The ability of a specially prepared water propolis extract (PWE) to preserve the functional activity of the intestinal mucosa after radiation exposure was studied. PWE was given orally (650 mg/kg) to rats five days prior to irradiation by 6 Gy and continued for further two days. Rats were sacrificed 24h later, intestinal segments were examined histologically and homogenates were used to assess relevant biochemical parameters reflecting intestinal injury. Irradiation led to a rise in the histological damage score, a rise in tissue TNF-α and TBARS, and a decrease in sucrase, alkaline phosphatase, GSH and cholecystokinin as well as a decrease in plasma citrulline. The findings reflect a decrease in intestinal functional activity. PWE preserved the intestinal integrity and largely protected against the changes induced in the histology damage score and all parameters measured, possibly as a result of the antioxidant and anti-inflammatory action of its caffeic acid content.

Non-alcoholic fatty liver disease following liver transplantation: a clinical review

Non-alcoholic steatohepatitis (NASH) is rapidly becoming the leading indication for liver transplantation (LT) in the United States. While post-transplantation outcomes are similar to other indications for transplant, recent evidence has suggested that reduction in risk factors for post-transplant metabolic syndrome may impose a significant survival benefit in this patient population. Cardiovascular mortality is the leading cause of death following transplantation for NASH. While pre-transplant pharmacologic and surgical approaches have been utilized to reduce cardiovascular risk factors following transplantation, the effectiveness of these treatment approaches in the post-transplant setting is poorly defined. Studies are urgently needed in the treatment of this rapidly growing population.

Treatment of nonalcoholic steatohepatitis in adults: present and future

Nonalcoholic steatohepatitis has become one of the most common liver-related health problems. This condition has been linked to an unhealthy diet and weight gain, but it can also be observed in nonobese people. The standard of care is represented by the lifestyle intervention. However, because this approach has several limitations, such as a lack of compliance, the use of many drugs has been proposed. The first-line pharmacological choices are vitamin E and pioglitazone, both showing a positive effect on transaminases, fat accumulation, and inflammation. Nevertheless, vitamin E has no proven effect on fibrosis and on long-term morbidity and mortality and pioglitazone has a negative impact on weight. Other drugs have been studied such as metformin, ursodeoxycholic acid, statins, pentoxiphylline, and orlistat with only partially positive results. Among the emerging treatments, telmisartan is particularly interesting as it seems to have an impact on insulin resistance, liver steatosis, inflammation, and fibrosis. However, the pathogenesis of steatohepatitis is highly complex and is determined by different parallel hits; indeed, the association of different drugs that act on various levels has been suggested. In conclusion, lifestyle intervention should be optimised and the associations of different drugs should be tested in large studies with long-term outcomes.

A multi-component herbal preparation, STW 5, shows anti-apoptotic effects in radiation induced intestinal mucositis in rats

PURPOSE

Intestinal mucositis is a common adverse effect in patients undergoing radiotherapy and constitutes a treatment-limiting condition. Since no agents are yet known that can adequately guard against its development, the search continues to find safe and effective measures. The present study was intended to investigate whether the herbal preparation, STW 5, could offer a potentially effective agent in this respect.

METHODS

Intestinal mucositis was induced in rats by exposing them to whole body gamma-irradiation (6 Gy). Rats were treated orally with STW 5 (5 or 10 ml/kg) for five days before and two days after irradiation. One day later, rats were sacrificed and segments of small intestine were examined histologically. Intestinal homogenates and serum samples were used to assess relevant parameters for apoptosis and different markers for inflammation and oxidative stress.

RESULTS

Exposure to radiation produced dose-dependent extents of intestinal injury associated with apoptotic changes with high radiation levels. Apoptosis was associated with an increase in cytosolic calcium, depletion of mitochondrial cytochrome c, B-cell lymphoma-2 and complex I. Oxidative stress parameters (reduced glutathione, thiobarbituric acid reactive substance and total nitrate/nitrite) were deranged. Inflammation markers (tumor necrosis factor and myeloperoxidase) and indices of intestinal damage (serum diamine oxidase) were increased. STW 5 protected to a large extent against histological changes and counteracted the deranged parameters.

CONCLUSION

The findings provide experimental evidence for the potential beneficial use of STW5 in protecting against the development of radiation-induced intestinal mucositis and associated changes in tissue biomarkers.

Intestinal mucosal barrier is injured by BMP2/4 via activation of NF-κB signals after ischemic reperfusion

Intestinal ischemic reperfusion (I/R) can cause dysfunction of the intestinal mucosal barrier; however, the mechanism of the intestinal mucosal barrier dysfunction caused by I/R remains unclear. In this study, using intestinal epithelial cells under anaerobic cultivation and an in vivo rat intestinal I/R model, we found that hypoxia and I/R increased the expression of BMP2/4 and upregulated BMP type Ia receptor and BMP type II receptor expression. We also found that exogenous BMP2/4 can activate the ERK and AKT signaling pathways in rat small intestine (IEC-6) cells, thereby activating NF-κB signaling, which leads to increased levels of inflammatory factors, such as TNF-α and IL-6. Furthermore, recombinant BMP2/4 decreased the expression of the tight junction protein occludin via the activation of the NF-κB pathway; these effects were abolished by treatment with the BMP-specific antagonist noggin or the NF-κB inhibitor pyrrolidine dithiocarbamate (PDTC). All these factors can destroy the intestinal mucosal barrier, thereby leading to weaker barrier function. On the basis of these data, we conclude that BMP2/4 may act as the pathogenic basis for intestinal mucosal barrier dysfunction when the intestines suffer an I/R injury. Our results provide background for the development pharmacologic interventions in the management of I/R injury.

Pentoxifylline attenuates nitrogen mustard-induced acute lung injury, oxidative stress and inflammation

Nitrogen mustard (NM) is a toxic alkylating agent that causes damage to the respiratory tract. Evidence suggests that macrophages and inflammatory mediators including tumor necrosis factor (TNF)α contribute to pulmonary injury. Pentoxifylline is a TNFα inhibitor known to suppress inflammation. In these studies, we analyzed the ability of pentoxifylline to mitigate NM-induced lung injury and inflammation. Exposure of male Wistar rats (150-174 g; 8-10 weeks) to NM (0.125 mg/kg, i.t.) resulted in severe histopathological changes in the lung within 3d of exposure, along with increases in bronchoalveolar lavage (BAL) cell number and protein, indicating inflammation and alveolar-epithelial barrier dysfunction. This was associated with increases in oxidative stress proteins including lipocalin (Lcn)2 and heme oxygenase (HO)-1 in the lung, along with pro-inflammatory/cytotoxic (COX-2(+) and MMP-9(+)), and anti-inflammatory/wound repair (CD163+ and Gal-3(+)) macrophages. Treatment of rats with pentoxifylline (46.7 mg/kg, i.p.) daily for 3d beginning 15 min after NM significantly reduced NM-induced lung injury, inflammation, and oxidative stress, as measured histologically and by decreases in BAL cell and protein content, and levels of HO-1 and Lcn2. Macrophages expressing COX-2 and MMP-9 also decreased after pentoxifylline, while CD163+ and Gal-3(+) macrophages increased. This was correlated with persistent upregulation of markers of wound repair including pro-surfactant protein-C and proliferating nuclear cell antigen by Type II cells. NM-induced lung injury and inflammation were associated with alterations in the elastic properties of the lung, however these were largely unaltered by pentoxifylline. These data suggest that pentoxifylline may be useful in treating acute lung injury, inflammation and oxidative stress induced by vesicants.

Non-compressive disorders of the chiasm

Chiasmal dysfunction produces a characteristic clinical picture, regardless of the mechanism. In most cases a compressive lesion is the cause. In occasional cases, however, no such extrinsic mass is found and other possible etiologies must be explored. In some of these cases, the pathologic process is identifiable with appropriate neuroimaging. For example, inflammation, infiltrative tumors, and radiation necrosis produce intrinsic chiasmal enhancement. Chiasmal ischemia may require specialized magnetic resonance (MR) sequences for diagnosis. Chiasmal hemorrhage, trauma and chiasmal herniation typically produce distinctive changes on noncontrasted imaging. In cases of metabolic insult, either toxic or hereditary, radiographic changes are typically absent. In each of these, the correct diagnosis can usually be made with a combination of clinical and radiographic features.

Remote ischemic preconditioning as treatment for non-ischemic gastrointestinal disorders: Beyond ischemia-reperfusion injury

Common gastrointestinal diseases such as radiation enteritis (RE), acute pancreatitis, inflammatory bowel diseases (IBD) and drug-induced hepatotoxicity share pathophysiological mechanisms at the molecular level, mostly involving the activation of many pathways of the immune response, ultimately leading to tissue injury. Increased oxidative stress, inflammatory cytokine release, inflammatory cell infiltration and activation and the up-regulation of inflammatory transcription factors participate in the pathophysiology of these complex entities. Treatment varies in each specific disease, but at least in the cases of RE and IBD immunosuppressors are effective. However, full therapeutic responses are not always achieved. The pathophysiology of ischemia-reperfusion (IR) injury shares many of these mechanisms. Brief and repetitive periods of ischemia in an organ or limb have been shown to protect against subsequent major IR injury in distant organs, a phenomenon called remote ischemic preconditioning (RIP). This procedure has been shown to protect the gut, pancreas and liver by modulating many of the same inflammatory mechanisms. Since RIP is safe and tolerable, and has shown to be effective in some recent clinical trials, I suggest that RIP could be used as a physiologically relevant adjunct treatment for non-ischemic gastrointestinal inflammatory conditions.

Effects of pentoxifylline on nonalcoholic fatty liver disease: A meta-analysis

AIM: To evaluate the effects of pentoxifylline therapy in patients with nonalcoholic fatty liver disease (NAFLD).

METHODS: We searched PubMed, Medline, Google Scholar, Embase, Web of Science, the Cochrane Library and the Chinese Biomedicine Database for all relevant controlled trials of pentoxifylline in patients with NAFLD from 1997 to July 2013. Five studies (3 randomized, double-blind, placebo-controlled trials and 2 prospective cohort studies with concurrent controls) were included in this meta-analysis. Statistical analysis was performed using RevMan 5.0 software.

RESULTS: Five randomized trials of 147 patients with NAFLD/nonalcoholic steatohepatitis (NASH) were included. The results showed that compared to placebo, pentoxifylline therapy resulted in a significant decrease in body weight (P = 0.04), alanine aminotransferase (P < 0.00001), aspartate transaminase (P = 0.0006), glucose (P = 0.0008) and tumor necrosis factor-α (P = 0.007), but did not significantly affect body mass index (P = 0.28), total cholesterol (P = 0.80), triglyceride (P = 0.98), alkaline phosphatase (P = 0.29), γ-glutamyl transferase (P = 0.39) and interleukin-6 (P = 0.38). With regard to histological changes, pentoxifylline only reduced the NAFLD activity score (P < 0.00001) and improved lobular inflammation (P < 0.0001). Improvements in steatosis grade (P = 0.11), ballooning (P = 0.10) and fibrosis (P = 0.50) were not obvious.

CONCLUSION: Pentoxifylline therapy results in weight loss, improved liver function and histological changes in patients with NAFLD/NASH. Therefore, pentoxifylline may be a new treatment option for NAFLD.

Effect of the new synthetic vitamin E derivative ETS-GS on radiation enterocolitis symptoms in a rat model

Radiation enterocolitis is a severe adverse event that occurs after radiotherapy for malignant abdominal tumors. In this study, the therapeutic effects of ETS-GS, a novel vitamin E derivative with antioxidative and anti-inflammatory abilities, were examined in a rat model of radiation enterocolitis. The radiation enterocolitis model was created by irradiation of male rats with a single dose of 10 Gy. ETS-GS was administered subcutaneously (10 mg/kg/day) for five consecutive days from two days prior to irradiation. The animals were sacrificed three days after irradiation; following which, ileal tissue samples were analyzed for macroscopic and histological findings, presence of apoptosis, degree of oxidative stress and inflammation. In the irradiated group, severe erosion was observed in the small intestine in addition to necrosis of the mucosal layer, swelling and invasion of inflammatory cells of the submucosal layer, and shortening of the crypts. In irradiated rats that received ETS-GS, mucosal injury in the small intestine was milder compared with that of irradiated rats that received no ETS-GS. In addition, ETS-GS decreased apoptosis in the small intestine and reduced the activity of myeloperoxidase and malondialdehyde, which are markers for inflammation and oxidative stress. ETS-GS with antioxidant activity has a therapeutic effect on the symptoms of radiation enterocolitis in a rat model.

Pentoxifylline aggravates fatty liver in obese and diabetic ob/ob mice by increasing intestinal glucose absorption and activating hepatic lipogenesis

BACKGROUND AND PURPOSE

Pentoxifylline is in clinical trials for non-alcoholic fatty liver disease and diabetic nephropathy. Metabolic and hepatic effects of pentoxifylline were assessed in a murine model of obesity and type 2 diabetes.

EXPERIMENTAL APPROACH

Pentoxifylline (100 mg·kg(-1) ·day(-1)) was administered for 4 days or 3 weeks in lean and obese/diabetic ob/ob mice. Plasma lipids, glucose, other metabolites and relevant enzymes were measured by standard assays. Hepatic lipids in vivo were assessed with magnetic resonance spectroscopy and by histology. Hepatic extracts were also analysed with RT-PCR and Western blotting.

KEY RESULTS

Four days of pentoxifylline treatment slightly increased liver lipids in ob/ob mice. After 3 weeks, pentoxifylline exacerbated fatty liver and plasma transaminases in ob/ob mice but did not induce liver steatosis in lean mice. Plasma glucose was highest in fed, but not fasted, ob/ob mice treated with pentoxifylline. During the first 10 min of an oral glucose tolerance test, blood glucose increased more rapidly in pentoxifylline-treated mice. Jejunal expression of glucose transporter 2 isoform was increased in pentoxifylline-treated obese mice. Hepatic activity of carbohydrate response element binding protein (ChREBP) increased after pentoxifylline in ob/ob, but not lean, mice. Hepatic expression of lipogenic enzymes was highest in pentoxifylline-treated ob/ob mice. However, pentoxifylline reduced markers of oxidative stress and inflammation in ob/ob liver.

CONCLUSION AND IMPLICATIONS

Pentoxifylline exacerbated fatty liver in ob/ob mice through enhanced intestinal glucose absorption, increased postprandial glycaemia and activation of hepatic lipogenesis. Long-term treatment with pentoxifylline could worsen fatty liver in some patients with pre-existing hyperglycaemia.

Effect of quercetin on impaired immune function in mice exposed to irradiation

Radiation used in cancer treatment may cause side effects such as inflammation. Quercetin is a polyphenol that reduces inflammation. This study evaluated the recovery efficacy of quercetin on impaired immune function in irradiation-induced inflammatory mice. Quercetin administered at two concentrations of 10 and 40 mg/kg body weight was initiated 2 weeks before irradiation and was continued 30 days after irradiation. The animals exposed/not exposed to radiation were sacrificed on radiation days 10 and 30. Splenocyte proliferation, which was diminished after irradiation, was enhanced significantly by quercetin supplementation after 30 days of irradiation. Cytokine secretion increased in the radiation group compared to that in the non-radiation control group. After 30 days of radiation, interleukin (IL)-1β and IL-6 secretion decreased significantly in the radiation-quercetin groups. When quercetin was administered for 44 days, it showed a possible protective effect against irradiation-induced inflammation in mice. Quercetin could be beneficial in the recovery of irradiation-induced increases in cytokine secretion.