Effect of pretreatment with high-dose ulinastatin in preventing radiation-induced pulmonary injury in rats

Pathogenic mechanisms and latest therapeutic approaches for radiation-induced lung injury: a narrative review

The treatment of thoracic tumors with ionizing radiation can cause radiation-induced lung injury (RILI), which includes radiation pneumonitis and radiation-induced pulmonary fibrosis. Preventing RILI is crucial for controlling tumor growth and improving quality of life. However, the serious adverse effects of traditional RILI treatment methods remain a major obstacle, necessitating the development of novel treatment options that are both safe and effective. This review summarizes the molecular mechanisms of RILI and explores novel treatment options, including natural compounds, gene therapy, nanomaterials, and mesenchymal stem cells. These recent experimental approaches show potential as effective prevention and treatment options for RILI in clinical practice.

Nicaraven Exerts a Limited Effect on Radiation-Induced Inhibition of Tumor Growth in a Subcutaneous Murine Tumor Model

Nicaraven selectively protects normal tissue from radiation-induced injury. To further develop the clinical application of nicaraven for mitigating the side effects of cancer radiotherapy, we investigated the potential effect of nicaraven administration in radiation-induced inhibition of tumor growth. A subcutaneous tumor model was established in mice by the injection of Lewis lung cancer cells at the back of the chest. X-ray radiation was delivered to the thoracic area and different doses of nicaraven (0, 20, 50, 100 mg/kg) were administrated intraperitoneally pre- or post-irradiation. The tumor size was measured every other day. Mice were euthanized on day 30, and the tumor weight and the levels of cytokines in tumor tissue were measured. Pre- or post-irradiation administration of nicaraven up to a dose of 100 mg/kg did not significantly diminish the radiation-induced inhibition of tumor growth, but post-irradiation administration of 20 and 50 mg/kg nicaraven resulted in relatively lower tumor weight. The levels of IL-1β, IL-6, IL-10, MCP-1, MIP-2a, TGF-β1, VEGF, p53, p21, cyclin D1 and caspase-3 in tumor tissue did not change by nicaraven administration and were not significantly associated with the tumor weights. According to our experimental data, nicaraven will not significantly diminish the radiation-induced inhibition of tumor growth, even with pre-irradiation administration at a high dose.

Tolerance limit of external beam radiotherapy combined with low-dose rate brachytherapy in normal rabbit tissue

BACKGROUND

Dosage-optimized multimodal radiotherapies that are safe for head and neck cancer patients are desirable. In this study, we investigated tissue tolerance to varying doses of external beam radiotherapy (EBRT) combined with low-dose rate brachytherapy in the neck of a rabbit model.

METHODS

Twenty rabbits were used in the four test groups (five each) with iodine-125 seeds implanted in the neck treated with EBRT in four doses at 50, 40, 30 and 20 Gy each. Twelve rabbits for three control groups (four each). Three months after implantation, all rabbits were euthanized, and target tissues were collected. Analyses included seed implantation assessment, histopathological evaluation, immunohistochemistry staining, terminal deoxynucleotidyl transferase dUTP nick end labeling assay, electron microscopy and statistics with the SPSS software.

RESULTS

Five rabbits died in the four test groups, and three rabbits died in the three control groups (one per group), which showed no significant difference by survival analysis. The calculated minimum peripheral dose was 17.6 Gy, the maximum dose near the seed was 1812.5 Gy, the D90 was 34.5 Gy and the mean dose was 124.5 Gy. In all groups that received radiation, apoptosis occurred primarily in the esophageal mucosa and corresponded to the dose of radiation; a higher dose caused a greater apoptosis, with significant difference between groups (P < 0.05). Electron microscopy of carotid arteries revealed that endothelial cells were swollen and some were shed from basement membrane, but no other noticeable tissue damages.

CONCLUSIONS

Limited EBRT at maximal dose (50 Gy) combined with the brachytherapy interstitially applied to the neck was tolerated well in the rabbit model.

Ulinastatin attenuates protamine-induced cardiotoxicity in rats by inhibiting tumor necrosis factor alpha

Protamine causes cardiac depression, which may be mediated by tumor necrosis factor alpha (TNF-α). Ulinastatin, a human urinary protease inhibitor, inhibits TNF-α. Here, we aimed to investigate whether ulinastatin prevented protamine-induced myocardial depression by inhibiting TNF-α. Rat hearts were perfused using a Langendorff system, and three protocols were followed. Protocol 1: The hearts were divided into saline, ulinastatin-low, and ulinastatin-high groups. Protamine was administered to each group, and myocardial contractility was the primary outcome. Protocol 2: The hearts were allotted to saline or ulinastatin group. Protamine was administered to each group. TNF-α expression in the coronary effluent and myocardial tissue was measured. Protocol 3: The hearts were allotted to saline and ulinastatin groups. Recombinant rat-TNF-α was administered to each group. Protamine alone reduced the maximum left ventricular pressure derivative (LV dP/dt max) by 45 ± 4%. In contrast, the reduction in LV dP/dt max was 4 ± 3% in the ulinastatin-high group. Compared with that in the saline group, the increase in TNF-α in the coronary effluent was attenuated in the ulinastatin group. Recombinant TNF-α alone reduced LV dP/dt max (- 21 ± 14%). In contrast, when TNF-α was added in the presence of ulinastatin, the decrease in LV dP/dt max was prevented significantly (- 3 ± 8%). We showed, for the first time, that ulinastatin protected against protamine-induced myocardial damage, both by inhibiting TNF-α synthesis and by directly preventing the cardiodepressant action of TNF-α.

Prevention and treatment of radiation-induced lung injury

Radiation-induced lung injury (RILI) is a common complication in cancer patients receiving local thoracic radiation and bone marrow transplantation conditioning. It is divided into early-stage radiation pneumonitis and advanced radiation fibrosis of the lung. This severely hampers the quality of life and survival of cancer patients. Meanwhile, RILI is a major factor limiting radiation doses in clinical practice, which affects the local control of cancer. Unfortunately, the mechanism of RILI is still not well defined, and there are no treatment options available for these patients. In this review we summarize the methods and agents used for the treatment and prevention of RILI, with the aim of increasing understanding of RILI.

Ulinastatin enhances autophagy against radiation-induced lung injury in mice

Background

To investigate the enhancement of autophagy by ulinastatin for protecting against radiation-induced lung injury (RILI) in mice.

Methods

Forty C57BL/6 mice were equally divided into (I) control (C), (II) irradiation (R), (III) ulinastatin (U), (IV) 3-methyladenine (3-MA) (M), and (V) ulinastatin plus 3-MA (U+M) groups. Three mice in each group were infected with adeno-associated virus (AAV) carrying green fluorescent protein (GFP)-1A/1B-light chain 3 (GFP-LC3) in the lung for the marker of autophagy. All mice in R, U, M and U+M groups were given chest irradiation (1 Gy/min, 12 min), following injection with normal saline in C and U groups, ulinastatin (500,000 IU/kg·d, i.p., 7 d) in U group, 3-MA (10 mg/kg·d, i.p., 7 d) in M group, and ulinastatin plus 3-MA in U+M group. The effects of ulinastatin on lung injury and autophagy were evaluated by electron microscope (EM), immunohistochemistry, mRNA expression levels of collagen alpha-1 (COL1A1), collagen alpha-2 (COL1A2), α-smooth muscle actin (α-SMA) and transforming growth factor β1 (TGF-β1), and protein levels of LC3, α-SMA, COL1A2, TGF-β1, matrix metalloproteinase-2 (MMP-2) and MMP-9.

Results

EM observation revealed that the radiation caused the injury of type I and II alveolar epithelial cells, which was improved by ulinastatin treatment associated with increased the numbers of autophagosomes. GFP-LC3 signals was significantly enhanced by ulinastatin detected by immune histochemical tests. At transcriptional and/or translational levels, ulinastatin significantly enhanced the expression levels of TGF-β1 and LC3 but reduced COL1A1, COL1A2, α-SMA, MMP-2 and MMP-9 after radiation-induced RILI.

Conclusions

Ulinastatin reduces RILI by enhancing autophagy, which might be a potential therapeutic drug in the protection against RILI.

MicroRNA-21 mediates bone marrow mesenchymal stem cells protection of radiation-induced lung injury during the acute phase by regulating polarization of alveolar macrophages

Background

Radiation-induced lung injury (RILI) often occurs in patients with non-small cell lung cancer (NSCLC) after radiotherapy, and the prognosis of patients with RILI is usually poor. This work plan to investigate the expression patterns of microRNA-21(miR-21) in NSCLC patients with RILI and the protective effects of miR-21 over-expressed bone marrow mesenchymal stem cells (BMSCs) against RILI in rat model.

Methods

MiR-21 expressions were determined in both serum samples and bronchoalveolar lavage fluid (BALF) samples from NSCLC patients after radiation therapy. The correlation between miR-21 expression and the follow-up clinical characterizations were determined. Further, miR-21 over-expressed BMSCs were transplanted into RILI rats and the protective effects were evaluated. BMSCs and alveolar macrophages (AMs) were co-cultured in vitro and the macrophage M1 polarization markers were determined by ELISA and qRT-PCR assays.

Results

Expression of miR-21 was significantly increased in NSCLC patients with RILI compared with control group, especially before or at 4 weeks after radiation therapy commenced. The miR-21 levels were highly correlated with IL-12, TNF-α, and IL-6 expressions and the severity of RILI. Animal based experiments demonstrated that BMSCs treatment had a remarkable effect on alleviating alveolitis in RILI rats, and miR-21 over-expression could enhance this effect significantly. Cell based experiments demonstrated that BMSCs notably inhibited M1 polarization of AMs and this inhibition is in a miR-21 dependent manner.

Conclusions

These results indicated that BMSCs could blocked the proinflammatory pathway of macrophage through miR-21 over-expression, thus could be a potential therapeutic strategy for RILI.

Radiation-Induced Lung Injury (RILI)

Radiation pneumonitis (RP) and radiation fibrosis (RF) are two dose-limiting toxicities of radiotherapy (RT), especially for lung, and esophageal cancer. It occurs in 5-20% of patients and limits the maximum dose that can be delivered, reducing tumor control probability (TCP) and may lead to dyspnea, lung fibrosis, and impaired quality of life. Both physical and biological factors determine the normal tissue complication probability (NTCP) by Radiotherapy. A better understanding of the pathophysiological sequence of radiation-induced lung injury (RILI) and the intrinsic, environmental and treatment-related factors may aid in the prevention, and better management of radiation-induced lung damage. In this review, we summarize our current understanding of the pathological and molecular consequences of lung exposure to ionizing radiation, and pharmaceutical interventions that may be beneficial in the prevention or curtailment of RILI, and therefore enable a more durable therapeutic tumor response.

Cytokines and radiation-induced pulmonary injuries

Radiation therapy is one of the most common treatment strategies for thorax malignancies. One of the considerable limitations of this therapy is its toxicity to normal tissue. The lung is the major dose-limiting organ for radiotherapy. That is because ionizing radiation produces reactive oxygen species that induce lesions, and not only is tumor tissue damaged, but overwhelming inflammatory lung damage can occur in the alveolar epithelium and capillary endothelium. This damage may result in radiation-induced pneumonitis and/or fibrosis. While describing the lung response to irradiation generally, the main focus of this review is on cytokines and their roles and functions within the individual stages. We discuss the relationship between radiation and cytokines and their direct and indirect effects on the formation and development of radiation injuries. Although this topic has been intensively studied and discussed for years, we still do not completely understand the roles of cytokines. Experimental data on cytokine involvement are fragmented across a large number of experimental studies; hence, the need for this review of the current knowledge. Cytokines are considered not only as molecular factors involved in the signaling network in pathological processes, but also for their diagnostic potential. A concentrated effort has been made to identify the significant immune system proteins showing positive correlation between serum levels and tissue damages. Elucidating the correlations between the extent and nature of radiation-induced pulmonary injuries and the levels of one or more key cytokines that initiate and control those damages may improve the efficacy of radiotherapy in cancer treatment and ultimately the well-being of patients.

Early Detection of the Acute Exacerbation of Interstitial Pneumonia after the Surgical Resection of Lung Cancer by Planned Chest Computed Tomography

Background

To improve postoperative outcomes associated with interstitial pneumonia (IP) in patients with lung cancer, the management of the postoperative a cute exacerbation of IP (PAEIP) was investigated.

Methods

Patients with primary lung cancer were considered to be at risk for PAEIP (possible PAEIP) based on a preoperative evaluation. The early phase of this study was from January 2001 to December 2008, and the late phase was from January 2009 to December 2014. In the early phase, chest computed tomography (CT) was performed for patients for whom PAEIP was suspected based on their symptoms, whereas in the late phase, chest CT was routinely performed within a few days postoperatively. The numbers of possible PAEIP cases, actual PAEIP cases, and deaths within 90 days due to PAEIP were compared between both phases.

Results

In the early and late phases, surgery was performed in 712 and 617 patients, 31 and 72 possible PAEIP cases were observed, nine and 12 actual PAEIP cases occurred, and the mean interval from the detection of PAEIP to starting treatment was 7.3±2.3 and 5.0±1.8 days, respectively. Five patients died in the early phase, and one patient died in the late phase. Significantly fewer PAEIP-related deaths were observed in the late phase (p<0.05).

Conclusion

Identifying patients at risk for PAEIP by routine postoperative CT examinations led to the early diagnosis and treatment of PAEIP, resulting in the reduction of PAEIP-related mortality.

Safety and tolerability of high-dose ulinastatin after 2-hour intravenous infusion in adult healthy Chinese volunteers: A randomized, double-blind, placebo-controlled, ascending-dose study

Ulinastatin, is a broad-spectrum protease inhibitor purified from human urine, inhibits endogenous proteases such as trypsin, α-chymotrypsin, hyaluronidase, and plasmin. It is widely being used at increasingly higher doses for the treatment of acute or chronic pancreatitis, severe infection, and acute organ failure. We aimed to evaluate the safety and tolerability of high-dose ulinastatin in healthy volunteers in our single center, randomized, double-blind, placebo-controlled, single-dose escalation study. Fifty-one healthy Chinese subjects were enrolled in 9 dose cohorts (3×10⁵ U, 6×10⁵ U, 12×10⁵ U, 20×10⁵ U, 30×10⁵ U, 45×10⁵ U, 60×10⁵ U, 70×10⁵ U, or 80×10⁵ U of ulinastatin) and randomized to UTI or matching placebo (n = 1). Each dose cohort was composed of 3–7 subjects. All subjects were required to have 2 h of intravenous infusion. Safety and tolerability were assessed throughout the study via monitoring of vital signs, physical examinations, clinical laboratory tests, 12-lead electrocardiograms, and interviews with the subjects about adverse events. Fifty-one subjects (35 men and 16 women) completed the study. A total of 13 AEs were reported by 10 subjects: 11 adverse events in the ulinastatin groups and 2 adverse events in the placebo group. Twelve of the adverse events were possibly related to the study drug. The most common drug-related adverse events included dizziness, pain at injection site, and a decrease in white blood cell count. All adverse events were of mild severity; none were serious. In conclusion, 2 hours of intravenous infusion of ulinastatin (3×10⁵ to 80×10⁵ U) was well tolerated by healthy Chinese subjects.

Current Status of Targeted Radioprotection and Radiation Injury Mitigation and Treatment Agents: A Critical Review of the Literature

As more cancer patients survive their disease, concerns about radiation therapy-induced side effects have increased. The concept of radioprotection and radiation injury mitigation and treatment offers the possibility to enhance the therapeutic ratio of radiation therapy by limiting radiation therapy-induced normal tissue injury without compromising its antitumor effect. Advances in the understanding of the underlying mechanisms of radiation toxicity have stimulated radiation oncologists to target these pathways across different organ systems. These generalized radiation injury mechanisms include production of free radicals such as superoxides, activation of inflammatory pathways, and vascular endothelial dysfunction leading to tissue hypoxia. There is a significant body of literature evaluating the effectiveness of various treatments in preventing, mitigating, or treating radiation-induced normal tissue injury. Whereas some reviews have focused on a specific disease site or agent, this critical review focuses on a mechanistic classification of activity and assesses multiple agents across different disease sites. The classification of agents used herein further offers a useful framework to organize the multitude of treatments that have been studied. Many commonly available treatments have demonstrated benefit in prevention, mitigation, and/or treatment of radiation toxicity and warrant further investigation. These drug-based approaches to radioprotection and radiation injury mitigation and treatment represent an important method of making radiation therapy safer.

Effects of CpG oligodeoxynucleotide 1826 on acute radiation-induced lung injury in mice

Background

The radiation-induced lung injury is a common complication from radiotherapy in lung cancer. CpG ODN is TLR9 activator with potential immune modulatory effects and sensitization of radiotherapy in lung cancer. This study aimed to examine the effect of CpG ODN on acute radiation-induced lung injury in mice.

Methods and results

The mouse model of radiation-induced lung injury was established by a single dose of 20 Gy X-rays exposure to the left lung. The results showed that the pneumonia score was lower in RT+CpG group than in RT group on 15th and 30th days. Compared with RT group, CpG ODN reduced the serum concentrations of MDA (P < 0.05) and increased the serum concentrations of SOD, GSH (P < 0.05). The serum concentration of TNF-α in RT+CpG group was lower on 15th and 30th days post-irradiation (P < 0.05).

Conclusion

The study demonstrated that CpG ODN has preventive effects of acute radiation-induced lung injury in mice. Lung inflammatory reaction and oxidative stress are promoted in the initiation of radiation-induced pneumonia. CpG ODN may reduce the injury of reactive oxygen species and adjust the serum TNF-α concentration in the mice after irradiation, which reduces the generation of the inflammatory cytokines.

Effects of different tidal volume ventilation on paraquat-induced acute lung injury in piglets

Background

The aim of this study was to explore the effects of different tidal volume (V_T) ventilation on paraquat-induced acute lung injury or acute respiratory distress syndrome (ALI/ARDS) in piglets.

Material/Methods

We developed ALI/ARDS models in piglets by intraperitoneal injection of paraquat (PQ). The piglets were randomly divided into three groups: small V_T group (V_T=6 ml/kg, n=6), middle V_T group (V_T=10 ml/kg, n=6), and large V_T group (V_T=15 ml/kg, n=6), with the positive end-expiratory pressure (PEEP) set as 10 cmH₂O. The hemodynamics were monitored by pulse-indicated continuous cardiac output (PiCCO) and the airway pressure changes and blood gas analysis indexes were recorded at different time points. The pathological changes were observed by lung puncture.

Results

The piglets showed ALI/ARDS in 4.5±0.8 hours after PQ intraperitoneal injection. PH, PaO₂ and oxygenation indexes in the three groups all decreased after modeling success compared with baseline, and PaCO₂ increased significantly. PH in the small VT group decreased most obviously after ventilation for 6 hours. PaO₂ and oxygenation indexes in the small VT group showed the most obvious increase after ventilation for 2 hours and were much higher than the other two groups after ventilation for 6 hours. PaCO₂ increased gradually after mechanical ventilation and the small VT group showed most obvious increase. The ELWI increased obviously after ventilation for 2 hours and then the small VT group clearly decreased. PIP and plateau pressure (Pplat) in the small VT group decreased gradually and in the middle and large VT group they increased after ventilation. The lung histopathology showed that the large VT group had the most severe damage and the small VT group had only minimal damage.

Conclusions

Small tidal volume ventilation combined with PEEP could alleviate the acute lung injury induced by paraquat and improve oxygenation.

Protective effect of ulinastatin in patients with non-small cell lung cancer after radiation therapy: a randomized, placebo-controlled study

Radiation-induced lung injury (RILI) is a frequent, sometimes life-threatening complication of radiation therapy for the treatment of lung cancer. The anti-inflammatory role of ulinastatin has been well documented, and the potential application of ulinastatin in management of acute lung injury has been suggested in multiple animal studies. In this article, we described a double-blind, randomized, placebo-controlled study in patients with non-small cell lung cancer. A total of 120 patients were randomized into two groups: the trial group was treated with ulinastatin for 3 days prior to and for the first 7 days of radiation therapy and the control group was treated with placebo for 10 days following the same schedule. The results from follow-up studies showed that the incidence and grade of RILI were significantly lower in the trial group than in the control group. Reduction in pulmonary function from baseline was significantly smaller in the trial group than that in the control group. Production of serum TGF-β1, TNF-α and IL-6 decreased significantly in the trial group promptly following radiation therapy. However, no difference in survival or tumour response rate was found between the two groups. The results indicated that ulinastatin exerted a protective effect on radiation-induced lung injury. Treatment with ulinastatin could be an effective management strategy and greatly improve the clinical efficacy of radiation therapy for patients with lung cancer.

Preventive effect of ulinastatin on postoperative complications, immunosuppression, and recurrence in esophagectomy patients

Background

To evaluate the potential efficacy of preventive effect of ulinastatin in esophagectomy patients.

Methods

Eighty patients with esophageal cancer were preoperatively allocated at random into two equal groups. Ulinastatin was administered to the treatment group (U) whereas the control group (C) received a placebo. The arterial oxygen tension and carbon dioxide tension were measured and the respiratory index (RI) was calculated. Plasma levels of circulating T lymphocyte subsets and interleukin 6 (IL-6) were measured and clinical courses of patients in the two groups were compared.

Results

RI in the U group was significantly lower than that in the C group. The rate of postoperative complications and the duration of ICU stay were significantly lower in the U group. Ulinastatin significantly increased the rate of CD3⁺ and CD4⁺ cells, and ratio of CD4⁺/CD8⁺, but decreased the rate of CD8⁺ cells and release of IL-6 compared to the C group on postoperative days 1 and 3. Patients within the C group showed worse recurrence free survival. Multivariate analysis revealed that ulinastatin administration significantly decreased the incidence of recurrence.

Conclusions

Ulinastatin had a preventive effect on postoperative complications and immunosuppression in esophagectomy patients, thereby prolongingrecurrence free survival.

Reactive oxygen species and x-ray disrupted spontaneous [Ca²⁺]I oscillation in alveolar macrophages

Radiation leads to a rapid burst of reactive oxygen species (ROS), which is considered to be one of the major causes of radiation-induced injury. ROS have previously been shown to induce changes in cytosolic Ca²⁺ ([Ca²⁺]i) including [Ca²⁺]i oscillation. However, the role of radiation in [Ca²⁺]i oscillation is poorly understood. The purpose of this study was to identify the effect of ROS and X ray on [Ca²⁺]i oscillation, as well as their role in radiation-induced lung injury. Alveolar macrophages were cultured in the absence and presence of different doses of hydrogen peroxide (H₂O₂) or exposed to X-ray irradiation with or without pretreatment of diphenyleneiodonium chloride (DPI, an inhibitor of NADPH oxidases) or tetrandrine (TET, a calcium entry blocker) and cytosolic Ca²⁺ concentration was detected by fluorescent Ca²⁺ indicator Fura-2. Rat radiation lung injury was induced in vivo by using 40 Gy X ray and DPI or TET was used to prevent radiation-induced lung injury. The results showed that there was spontaneous [Ca²⁺]i oscillation in alveolar macrophages under normal conditions, and treatment of H₂O₂ (100-500 μM) or 2 Gy X ray inhibited the spontaneous [Ca²⁺]i oscillation and induced [Ca²⁺]i rise. TET abolished H₂O₂ or X ray induced [Ca²⁺]i rise in alveolar macrophages, and attenuated X ray- induced rat alveolitis in vivo. DPI prevented X-ray-induced inhibition of [Ca²⁺]i oscillation in alveolar macrophages and prevented X-ray-induced rat alveolitis. Taken together, the data suggest that the disruption of [Ca²⁺]i oscillation and induction of [Ca²⁺]i rise through ROS is involved in the mechanism of radiation-induced lung injury.

Rabbit model of radiation-induced lung injury

OBJECTIVE

To explore the feasibility of establishing an animal model of chronic radiation-induced lung injury.

METHODS

Twenty-eight New Zealand white rabbits were randomly divided into 3 groups (the right lung irradiation group, the whole lung irradiation group and the control group). Animal model of radiation-induced lung injury was established by high-does radiotherapy in the irradiation groups, then all rabbits underwent CT and pathological examinations at 1, 2, 4, 8, 12, 16 weeks, respectively after radiation.

RESULTS

Within 4 weeks of irradiation, some rabbits in the right lung irradiation group and whole lung irradiation group died. CT and pathological examinations all showed acute radiation pneumonitis. At 8-12 weeks after irradiation, CT scanning showed ground glass samples signs, patchy shadows and fibrotic stripes. Pathological examination showed the fibrosis pulmonary alveolar wall thickened obviously.

CONCLUSIONS

The clinical animal model of chronic radiation-induced lung injury which corresponds to practical conditions in clinic can be successfully established.

Ulinastatin reduces pathogenesis of phosgene-induced acute lung injury in rats

Phosgene (CG) is an industrial chemical used to make plastics, rubbers, dyestuff, and pesticides. Although the inhalation of CG is relatively uncommon, its accidental exposure can lead to acute lung injury (ALI). Ulinastatin, a urinary trypsin inhibitor, has been emerged to use for the treatment of acute inflammatory state of a number of organs including the lung. In this study, we examined the pathogenic changes in the lungs after the inhalation of CG gas and also examined the effect of ulinastatin treatment in reversing these changes in rats. We found that the rats exposed to CG gas at a dose of 5.0 g/m(3) for 5 min led to ALI after 6 h. The signs of lung injury include pulmonary edema, hemorrhage, and cellular infiltration in pulmonary alveoli. In addition, interleukin-15 (IL-15) and intercellular adhesion molecule-1 (ICAM-1) were significantly increased in CG-inhaled animals. Ulinastatin administration at 1 h postexposure significantly reduced the intensity of all the pathological changes in the lungs of these CG-exposed animals. Ulinastatin at a dose of 400 U/g was shown to decrease the total number of cells in bronchoalveolar lavage fluid and the levels of IL-15 and ICAM-1 in the serum. We also found that the structure of the lung was protected by ulinastatin treatment. Thus, our data suggest that ulinastatin can be used as an effective drug for the treatment of CG-induced ALI. The serum levels of IL-15 and ICAM-1 can be used as the markers of lung injury after exposure to CG and may also serve as useful therapeutic targets at an early stage. The effects of long-term treatment of ulinastatin and the mechanisms by which ulinastatin decreases the infiltration of blood cells and reduces cytokines need further investigation.

Analysis of the physical activity effects and measurement of pro-inflammatory cytokines in irradiated lungs in rats

PURPOSE

To study if the pre-radiotherapy physical activity has radio-protective elements, by measuring the radio-induced activation of pro-inflammatory cytokines as interleukin-6 (il-6), transforming growth factor -β (tgf -β), tumor necrosis factor -α (tnf-α) and protein beta kinase β (ikkβ), through western blotting analysis.

METHODS

A randomized study with 28 Wistar hannover rats, males, with a mean age of 90 days and weighing about 200 grams. The animals were divided into three groups: (GI, GII and GIII). GIII group were submitted to swimming for eight weeks (zero load, three times a week, about 30 minutes). Then, the groups (except the control group) were submitted to irradiation by cobalt therapy, single dose of 3.5 gray in the whole body. All animals were sacrificed by overdose of pentobarbital, according to the time for analysis of cytokines, and then a fragment of the lower lobe of the right lung went to western blotting analysis.

RESULTS

The cytokines IKK β, TNF-α and IL-6 induced by radiation in the lung were lower in the exercised animals. However, exercise did not alter the radiation-induced increase in tgf-β.

CONCLUSION

The results show a lower response in relation to inflammatory cytokines in the group that practiced the exercise pre-radiotherapy, showing that exercise can protect tissues from tissue damage due to irradiation.

Angiotensin converting enzyme inhibitors mitigate collagen synthesis induced by a single dose of radiation to the whole thorax

Our long-term goal is to use angiotensin converting enzyme (ACE) inhibitors to mitigate the increase in lung collagen synthesis that is induced by irradiation to the lung, which could result from accidental exposure or radiological terrorism. Rats (WAG/RijCmcr) were given a single dose of 13 Gy (dose rate of 1.43 Gy/min) of X-irradiation to the thorax. Three structurally-different ACE inhibitors, captopril, enalapril and fosinopril were provided in drinking water beginning 1 week after irradiation. Rats that survived acute pneumonitis (at 6-12 weeks) were evaluated monthly for synthesis of lung collagen. Other endpoints included breathing rate, wet to dry lung weight ratio, and analysis of lung structure. Treatment with captopril (145-207 mg/m(2)/day) or enalapril (19-28 mg/m(2)/day), but not fosinopril (19-28 mg/m(2)/day), decreased morbidity from acute pneumonitis. Lung collagen in the surviving irradiated rats was increased over that of controls by 7 months after irradiation. This increase in collagen synthesis was not observed in rats treated with any of the three ACE inhibitors. Analysis of the lung morphology at 7 months supports the efficacy of ACE inhibitors against radiation-induced fibrosis. The effectiveness of fosinopril against fibrosis, but not against acute pneumonitis, suggests that pulmonary fibrosis may not be a simple consequence of injury during acute pneumonitis. In summary, three structurally-different ACE inhibitors mitigate the increase in collagen synthesis 7 months following irradiation of the whole thorax and do so, even when therapy is started one week after irradiation.

Safety of postoperative administration of human urinary trypsin inhibitor in lung cancer patients with idiopathic pulmonary fibrosis

Background

Patients with idiopathic pulmonary fibrosis (IPF) undergoing pulmonary resection for lung cancer carry risks of acute exacerbations of IPF (AE) postoperatively. Currently, agents which may attenuate AE are actively sought. Urinary trypsin inhibitor, ulinastatin, is a synthetic glycoprotein which may potentially inhibit various inflammatory factors associated with the development and progression of IPF. The present study was done to evaluate the effects of administration of high dose ulinastatin in lung cancer patients with IPF immediately following lung resection.

Methods

Patients with IPFs radiologically diagnosed on high resolution CT, and histologically diagnosed resectable lung cancers, were eligible for the study. The effects of escalating doses of ulinastatin 3×10⁵, 6×10⁵, and 9×10⁵ units/body/day, administered postoperatively for 3 days were evaluated. The endpoints were safety and feasibility.

Results

Nine patients were evaluated, in cohorts of 3 patients per dosage. Postoperative follow up ranged from 3 to 12 months (median 9 months). The postoperative courses were uneventful in all patients. No subjective adverse events such as abdominal symptoms or skin rashes, or objective adverse events as per serum laboratory tests, such as liver or kidney dysfunctions potentially attributable to ulinastatin administration were observed. AE was seen in one patient at 3 months after surgery, but since this occurred shortly after administration of chemotherapy, it was considered to be attributable to the chemotherapy rather than surgery.

Discussion

Ulinastatin administration after lung resection in lung cancer patients with IPF was considered to be safe and feasible. Further study is planned at the highest dose of this study to evaluate efficacy.

Trial Registration

UMIN.ac.jp/ctr/UMIN000002410

Proteomic analysis of radiation-induced changes in rat lung: Modulation by the superoxide dismutase mimetic MnTE-2-PyP(5+)

PURPOSE

To identify temporal changes in protein expression in the irradiated rat lung and generate putative mechanisms underlying the radioprotective effect of the manganese superoxide dismutase mimetic MnTE-2-PyP(5+).

METHODS AND MATERIALS

Female Fischer 344 rats were irradiated to the right hemithorax with a single dose of 28 Gy and killed from day 1 to 20 weeks after irradiation. Proteomic profiling was performed to identify proteins that underwent significant changes in abundance. Some irradiated rats were administered MnTE-2-PyP(5+) and changes in protein expression and phosphorylation determined at 6 weeks after irradiation.

RESULTS

Radiation induced a biphasic stress response in the lung, as shown by the induction of heme oxygenase 1 at 1-3 days and at 6-8 weeks after irradiation. At 6-8 weeks after irradiation, the down-regulation of proteins involved in cytoskeletal architecture (filamin A and talin), antioxidant defense (biliverdin reductase and peroxiredoxin II), and cell signaling (β-catenin, annexin II, and Rho-guanosine diphosphate dissociation inhibitor) was observed. Treatment with MnTE-2-PyP(5+) partially prevented the apparent degradation of filamin and talin, reduced the level of cleaved caspases 3 and 9, and promoted Akt phosphorylation as well as β-catenin expression.

CONCLUSION

A significant down-regulation of proteins and an increase in protein markers of apoptosis were observed at the onset of lung injury in the irradiated rat lung. Treatment with MnTE-2-PyP(5+), which has been demonstrated to reduce lung injury from radiation, reduced apparent protein degradation and apoptosis indicators, suggesting that preservation of lung structural integrity and prevention of cell loss may underlie the radioprotective effect of this compound.