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We reported earlier that replacement of casein by soy protein in the diets of rats exposed to the carcinogen, dimethylbenz[a]anthracene (DMBA), not only delayed the initiation of breast tumor but also had a protective effect against the development of aggressive tumor. The aim of this study was to elucidate the molecular mechanism by which soy protein offers these beneficial effects. Tumor was developed by gavage administration of single dose of 80 mg/kg of DMBA into 50-day old female rats, maintained on a standard AIN-76A diet containing either casein or soy protein. After ~120 days of DMBA administration, we evaluated the role of MAPK phosphorylation and subsequent AP-1 activation on the differential effects of soy protein and casein on the development of aggressiveness and progression of DMBA-induced breast tumor and determined if soy protein controls MMP-9 and uPAR expression by modifying AP-1 activity. The present study demonstrates that the beneficial effect of soy protein in breast tumor development is mediated by control of MAPK/AP-1 signaling. It is concluded that deactivation of MAPK pathway lead to down-regulation of the AP-1 activation which in turn down regulates the target gene and may be responsible for controlling breast tumor aggressiveness. Thus, it is suggested that MAPKs (ERK, p38 and JNK), MMP-9 and uPAR may be a potential target for anticancer therapy inhibiting tumor vasculature and invasion stimulated by tumor-associated stroma, and regulating the target gene and may be responsible for the beneficial effects of soy protein.

Immunotherapy has become one of the greatest advances in medical oncology over the last century; however, the optimal application for the treatment of different types of cancer remains an active area of investigation. Modern immunotherapy strategies augment the immune system and ideally, permit durable tumor-specific immune memory to target and kill cancer cells. This era began when first immune checkpoint inhibitor, ipilimumab, was approved. In fact, several monoclonal antibodies that mediate the immune checkpoint receptors have provided the most clinically meaningful improvement for cancer patients to date. Checkpoint blockade as monotherapy has demonstrated some encouraging results, although some combination strategies appear to augment those responses and may be particularly effective when administered earlier in the course of disease. Additionally, we have also discussed previous and ongoing clinical studies testing individual or combination immunotherapy in cancer patients. Overall, the goal of this review is to provide a summary and current status of immune checkpoints and their inhibitors as therapeutic approaches of cancer immunotherapy and highlight promising future directions. Clinical Trials Registration Numbers: NCT00094653, NCT00257205, NCT01866319, NCT02142738, NCT02302807, NCT01903993, NCT02125461, NCT00732082, NCT01968109, NCT02061761, NCT02817633, NCT03489343, NCT04570839, NCT00298181, NCT00298168, NCT00876902, NCT03812328, NCT02812875, NCT04475523, NCT02768558, NCT02617589, NCT02039674, NCT02030834, NCT03545815, NCT03289962.

Cigarette smoke (CS) exposes lungs to oxidative stress and inflammation and is a major risk factor for the development of chronic obstructive pulmonary disease (COPD). COPD is a complex lung disease characterized by chronic inflammation with limited airflow and chronic bronchitis associated with mucus hypersecretion, thickened small airway walls, and emphysema. CS-induced oxidative stress is responsible for altered cellular metabolism, including increased infiltrating immune cells, pro-inflammatory cytokine production, protease–antiprotease imbalance, lipid peroxidation, apoptosis, upregulation of unfolded protein response (UPR), and protein misfolding. This chapter reviews the current knowledge on different mechanisms through which both direct and secondhand CS-induced oxidative stress in lungs plays a significant role in the pathogenesis of COPD. Despite the presence of considerable reports recognizing the harmful effects of CS-generated oxidative stress, effective treatment for COPD is lacking. Extensive research on the immune and pathogenetic mechanisms of COPD will help in developing new treatment strategies. Clinical trials leveraging multiple antioxidants, anti-inflammatory processes, and UPR inhibitors are urgently needed to advance COPD therapies.

This is a comprehensive review about the role of direct and second hand cigarette smoke exposure in the development of childhood asthma. Smoking, both during pregnancy and postnatal have an adverse impact on the infant's chances of developing respiratory illness. Second hand smoke exposure has also known to cause worsening of childhood asthma with an impact on hospital admissions. Correlation between maternal second hand smoke exposure during pregnancy and development of childhood asthma has also been investigated. It is, thus essential to address this prenatally as well as post-natal by reducing smoking as well as smoke exposure.

Consistent with the biological relevance of cathepsins B and D, their overexpression, translational or post-translational modifications, and mitogenic effects are hallmarks of breast cancer. Several studies have established a link between increased expression of cathepsins B and D and tumor growth, invasion, and metastasis. This review outlines the potential role of these two cathepsins, specifically in breast cancer, and different mechanisms involved during tumor progression and metastasis. The development of various therapeutic strategies, including specific inhibitors, gene targeted therapy, and antibodies against cathepsins in an attempt to curb breast tumor progression holds a promising future. However, from a translational perspective, further extensive studies are needed in order to unravel the therapeutic abilities of cathepsins B and D in controlling breast cancer.

Vitamin A (VA) and its active metabolites play an essential role in lung airway function. Patients with moderate to severe chronic obstructive pulmonary disease (COPD) have a lower serum retinol concentration, and improvement of their 1-second Forced Expiratory Volume (FEV1) is achieved with VA supplementation. In order to test our hypothesis that the VA signaling pathway is compromised in COPD, we obtained 20 lung samples from COPD patients differing in the degree of emphysema as judged by their FEV% values. All were smokers or were exposed to secondhand smoke. Levels of VA (retinol/retinyl ester), tocopherols and carotenoids (lutein, beta-carotene) in these samples were determined using HPLC. Additional analytes beside VA were included for their known roles as antioxidants and modulators of VA-action. VA levels (retinol/retinyl ester) decreased significantly with the increase in severity of emphysema. Among other analytes, α-tocopherol levels fell by 25.8% in the severe emphysema group in comparison to the mild emphysema group, and lutein levels similarly decreased in severe compared to moderate emphysema groups. However, beta-carotene levels remained unchanged. Thus there is a significant linear correlation between lung VA-levels and the severity of emphysema. There was also a significant reduction in the levels of α-, δ-tocopherol and lutein in the severe emphysema group of COPD patients who either smoked or were exposed to smoke.

Consumption of α-lactalbumin as dietary protein offers a beneficial effect on breast cancer development. Breast cancer was developed by gavage administration of single dose of dimethylbenz(a)anthracene (DMBA) in female rats, maintained on AIN-76A diet with either 20% casein or α-lactalbumin (a component of whey protein). All tumors were detected by palpation. After approximately 130 days of DMBA administration, the animals were euthanized. There was a delay in the development of breast tumor in the α-lactalbumin group in comparison to the casein group. The number of tumors per rat was less in the α-lactalbumin group than that in the casein group at any time point up to 130 days after DMBA administration. Also the incidence of tumors and tumor volume was less in the α-lactalbumin group than those in the casein group. The casein group had a mixture of grade I, grade II and grade III tumors whereas the α-lactalbumin group had mostly grade I tumor. Furthermore, the proliferative index was significantly lower in the α-lactalbumin group than that in the casein group.

Intratracheal infusion of 2-chloroethyl ethyl sulfide (CEES), a mustard gas analog and a chemical warfare agent is known to cause massive damage to lung. The purpose of this study was to determine whether intratracheal CEES infusion causes neuronal damage. Histological, immunohistochemical, and Western blot studies indicated that CEES treatment caused dose-dependent increases in blood cell aggregation, microglial cell number, microglial activation, and brain inflammation. In addition, an increased expression of α-synuclein and a decreased expression of the dopamine transporter were observed. The results indicate that intratracheal CEES infusion is associated with changes in brain morphology mediated by an increase in α-synuclein expression, leading to neurotoxicity in a guinea pig model. These changes may be mediated by oxidative stress. Furthermore, the present study indicates for the first time that intratracheal infusion of a single dose of CEES can cause neuroinflammation, which may lead to neurological disorders in later part of life. © 2011 Wiley Periodicals, Inc. J Biochem Mol Toxicol 26:23–30 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/jbt.20409

We reported earlier in a guinea pig model that exposure of 2-chloroethyl ethyl sulfide (CEES), a mustard gas analog, causes lung injury associated with the activation of tumor necrosis factor alpha (TNF-alpha), mitogen activated protein kinases (MAPK) signaling, and activator protein-1 (AP-1) transcription factor. Our earlier studies also revealed that antioxidant liposomes can be used as antidotes. Proinflammatory cytokines IL-1, IL-6, and TNF-alpha, either alone or in combination, can induce the activation of another group of transcription factors, namely SAF-1 (serum accelerator factor-1)/MAZ (Myc-associated zinc finger protein). Phosphorylation of SAF-1 via MAPK markedly increases its DNA-binding and transactivational potential. The objective of the present study was to investigate whether CEES exposure causes activation of IL-1 beta, IL-6, and SAF-1/MAZ and whether these effects can be prevented by antioxidant liposomes. A single dose (200 microL) of the antioxidant liposome mixture was administered intratracheally after 5 min of exposure of CEES (0.5 mg/kg). The animals were sacrificed either 1 h or 30 days after CEES exposure. CEES exposure caused an upregulation of proinflammatory cytokines IL-6 and IL-1 beta in the lung along with an increase in the activation of transcription factor SAF-1/MAZ. The antioxidant liposomes treatment significantly blocked the CEES-induced activation of IL-6, IL-1 beta, and SAF-1/MAZ. This might suggest that antioxidant liposomes might offer a potential therapeutic strategy against inflammatory diseases associated with activation of these bioactive molecules.

This study aims to establish the antiproliferative effects of PK11195, a peripheral benzodiazepine receptor antagonist (PBR) in rat mammary tumor cells. Breast tumors were induced by administration of a carcinogen, dimethylbenz[a]anthracene to 50-day-old female rats maintained on a standard AIN-76A diet with casein as the protein source. The tumors were developed approximately after 120 days. The tumors were of grade I (20%), grade II (60%), and grade III (20%). The tumors were isolated and cultured in DMEM/F12 media with supplements. We characterized the properties of the isolated cells and study the effect of PK11195 on those cells. We were successful in growing breast tumor cells up to 30 passages for cellular characterization. These cells had high reactivity with Ki-67 and PCNA antibodies suggesting high proliferation rate. These cells were highly invasive as evident by matrigel invading ability. Furthermore, these cells acquired a positive response for CD-31 and VEGF antibodies suggesting angiogenic potential, and also possessed migrating ability/motility as evident by the wound healing properties. These cells expressed elevated levels of PBR, a cancer promoting gene. The proliferation, invasion and migration appear to decrease when treated with PK11195, a PBR antagonist. Furthermore, PK11195 treatment caused an increase in apoptosis as evident by increase in the levels of annexin V. However, the inhibition of cell proliferation by PK11195 was counteracted by Ro5-4864, a PBR agonist. Thus, PBR antagonist may be a potential therapeutic agent for the control of aggressiveness of breast cancer.

We have recently reported that antioxidant liposomes can be used as antidotes for mustard gas induced lung injury in guinea pigs. The maximum protection was achieved with a liposome composed of tocopherols (alpha, gamma, delta) and N-acetylcysteine (NAC) when administered after 5 min of exposure of 2-chloroethyl ethyl sulfide (CEES), a half sulfur mustard gas. We also reported an association of mustard gas-induced lung injury with an activation of MAPK/AP-1 signaling pathway and cell proliferation. The objective of the present study was to investigate whether CEES-induced MAPKs/AP-1 signaling pathway is influenced by antioxidant liposome therapy. A single dose (200 microl) of the antioxidant liposome was administered intratracheally after 5 min of exposure of CEES (0.5 mg/kg). The animals were sacrificed after 1h and 30 days of CEES exposure. Although the liposome treatment did not have any significant effect on the activation of the MAPKs family (ERK1/2, p38 and JNK1/2), it significantly counteracted the CEES-induced activation of AP-1 transcription factors and corresponding increase in the protein levels of Fos, ATF and Jun family members. The liposome treatment significantly blocked the CEES-induced increase in the protein levels of cyclin D1, a cell cycle protein and PCNA, a cell differentiation marker. Furthermore, it protected lung against CEES-induced inflammation and infiltration of neutrophils, eosinophils and erythrocytes in the alveolar space. This suggests that the protective effect of antioxidant liposome against CEES-induced lung damage is mediated via control of AP-1 signaling.

It has been reported that there is an ameliorative effect of cigarette smoking on certain neurological responses and neurodegenerative disorders. The purpose of this study was to examine the neurochemical and neurobehavioral response of cigarette smoke (CS) in the adult male guinea pig brain. Both acute and chronic CS exposure enhanced locomotor behavior and caused a decrease in midbrain dopamine (DA) levels and corresponding increase in 3,4-dihydroxyphenylacetic acid (DOPAC) levels. In addition, CS caused a significant increase in the protein levels of the dopamine D1 and D2 receptors. CS caused a significant increase in the binding capacity of the D1 receptor and a significant decrease in the binding capacity of D2. Furthermore, CS caused a significant increase in the binding capacity of the dopamine transporter (DAT). The mechanism by which cigarette smoke exposure increases locomotor activity remains to be elucidated but may include modulation of dopamine neuron activity that emerges after repeated direct smoke exposure.

There are a number of sites that are required for the production and/or action of all-trans retinoic acid (ATRA). In particular, interruption of different components of the chain of trafficking and metabolism has been associated with cancers arising in numerous organs of the body. Preliminary work suggests that such interruptions may be a factor in lung disorders induced by the smoke exposure. The active metabolite of retinoid, ATRA offers a therapeutic strategy to protect against functional abnormality in the lung, including chronic obstructive pulmonary disease (COPD). This review deals with the lung retinoid metabolism and mediators of retinoid trafficking and signaling with special emphasis on their roles in health and disease.

Exposure to mustard gas causes inflammatory lung diseases including acute respiratory distress syndrome (ARDS). A defect in the lung surfactant system has been implicated as a cause of ARDS. A major component of lung surfactant is dipalmitoyl phosphatidylcholine (DPPC) and the major pathway for its synthesis is the cytidine diphosphocholine (CDP-choline) pathway. It is not known whether the ARDS induced by mustard gas is mediated by its direct effects on some of the enzymes in the CDP-choline pathway. In the present study we investigated whether mustard gas exposure modulates the activity of cholinephosphotransferase (CPT) the terminal enzyme by CDP-choline pathway. Adult guinea pigs were intratracheally infused with single doses of 2-chloroethyl ethyl sulfide (CEES) (0.5 mg/kg b.wt. in ethanol). Control animals were injected with vehicles only. The animals were sacrificed at different time and the lungs were removed after perfusion with physiological saline. CPT activity increased steadily up to 4 h and then decreased at 6 h and stabilized at 7 days in both mitochondria and microsomes. To determine the dose-dependent effect of CEES on CPT activity we varied the doses of CEES (0.5-6.0 mg/kg b.wt.) and sacrificed the animals at 1 h and 4 h. CPT activity showed a dose-dependent increase of up to 2.0 mg/kg b.wt. of CEES in both mitochondria and microsomes then decreased at 4.0 mg/kg b.wt. For further studies we used a fixed single dose of CEES (2.0 mg/kg b.wt.) and fixed exposure time (7 days). Lung injury was determined by measuring the leakage of iodinated-bovine serum albumin into lung tissue and expressed as the permeability index. CEES exposure (2.0 mg/kg b.wt. for 7 days) caused a significant decrease of both CPT gene expression (approximately 1.7-fold) and activity (approximately 1.5-fold) in the lung. This decrease in CPT activity was not associated with any mutation of the CPT gene. Previously we reported that CEES infusion increased the production of ceramides which are known to modulate PC synthesis. To determine whether ceramides affect microsomal CPT activity the lung microsomal fraction was incubated with different concentrations of C(2)-ceramide prior to CPT assay. CPT activity decreased significantly with increasing dose and time. The present study indicates that CEES causes lung injury and significantly decreases CPT gene expression and activity. This decrease in CPT activity was not associated with any mutation of the CPT gene is probably mediated by accumulation of ceramides. CEES induced ceramide accumulation may thus play an important role in the development of ARDS by modulating CPT enzyme.

Manganese superoxide dismutase (Mn-SOD), localized at the mitochondrial matrix, has the ability to protect cells against oxidative damage. It has been reported that low levels of Mn-SOD gene expression cause the development of certain kind of tumors. On the other hand, overexpression of Mn-SOD gene may play an important role in the development of cancer. In our study, we find that Mn-SOD activity was higher in nonaggressive (MCF-7) and aggressive (BT-549 and 11-9-14) breast cancer cell lines compared to that of nontumorigenic (MCF-12A and MCF-12F) mammary epithelial cell lines. We also observed an increased expression of Mn-SOD gene in cancerous cell lines. The elevated level of SOD activity in nonaggressive and aggressive breast epithelial cell lines was associated with some changes in nucleotide sequence.

This is a comprehensive review on the harmful health effects of cigarette smoking. Tobacco smoking is a reprehensible habit that has spread all over the world as an epidemic. It reduces the life expectancy among smokers. It increases overall medical costs and contributes to the loss of productivity during the life span. Smoking has been shown to be linked with various neurological, cardiovascular, and pulmonary diseases. Cigarette smoke not only affects the smokers but also contributes to the health problems of the non-smokers. Exposure to environmental tobacco smoke contributes to health problems in children and is a significant risk factor for asthma. Cigarette smoke contains several carcinogens that alter biochemical defense systems leading to lung cancer.

Membrane phospholipids as well as fatty acid profile of cell membrane phospholipids are altered in tumorigenicity and malignancy. Synthesis of total cellular phosphatidylcholine (PC) can be used as a marker for membrane proliferation in neoplastic mammary gland tissues. Cholinephosphotransferase (CPT), the terminal enzyme in the de novo synthesis of PC, has an important role in regulating the acyl group of PC in mammalian cells. In this study, the effect of neoplasia on CPT was examined. The gene shows an elevated expression in cancerous (11-9-14) breast epithelial cell line when compared to that of normal non-tumorigenic (MCF-12A) breast epithelial cell line. Four nucleotide substitutions are observed in the cancer cell line. Of these, three are null mutations, but the third one shows an interesting serine to tyrosine substitution (at amino acid position 89 of our partial sequence which corresponds to position 323 of the CPT sequence reported as NM_020244 in GenBank) in 11-9-14 cells. The tyrosine is present in the right context of KSELYQDT, which directs tyrosine phosphorylation at the tyrosine site. Biochemical approach also reveals a 1.5-fold stimulation in CPT activity in 11-9-14 cells compared to that of the MCF-12A cells.

The present study was performed to investigate the effect of oltipraz on passive smoke-induced alteration in renal glyoxalase system of rats. Adult Sprague-Dawley rats were exposed daily to passive cigarette smoke in a whole-body exposure chamber 6 h per day for 2, 4 and 12 weeks. The animals being sacrificed after 2 and 12 weeks were maintained on control diet, powdered 4% Teklad rat chow (Harlan Teklad, Madison, WI, USA). The 4 weeks group was divided into three subgroups, one receiving control diet, other two receiving control diet supplemented with two doses of oltipraz (either 167 or 500 ppm), starting 1 week prior to initiation of smoke exposure until the end of the experiment. The activity of glyoxalase I was higher in animals exposed for 4 and 12 weeks of passive smoke than those exposed for 2 weeks. There was no significant difference between 4 and 12 weeks. Glyoxalase II activity was lower in animals exposed to passive smoke for 4 weeks than those exposed for 2 weeks. However, the activity approached the basal level after 12 weeks of exposure. Furthermore, oltipraz treatment maintained the activity of both glyoxalase closer to the basal levels.

Cigarette smoking is associated with a number of fatal diseases, including cancer of different organs. A number of oxoaldehydes are found in cigarette smoke, among which methylglyoxal (MG) is known to cause toxicity to cells upon accumulation. In biological systems, MG is converted to s-d-lactoylglutathione by glyoxalase I with reduced glutathine (GSH) as a cofactor, and s-d-lactoylglutathione is converted to D-lactic acid with simultaneous regeneration of GSH, by glyoxalase II. In the present study, we have investigated the status of the glyoxalase enzymes in kidney tissues from rats exposed to passive cigarette smoke. No significant change has been noted in glyoxalase I activity. Glyoxalase II was decreased during 1 and 2 weeks of exposure, and after that the activity was increased. The initial decrease in the activity of gly II may be due to the excess amount of methylglyoxal generated due to smoke exposure or the adduct formed by MG and GSH which known to inhibit gly II activity. Both enzymes help in the detoxification of cigarette smoke induced chemicals and biochemicals.

We have earlier identified the presence of a 36 kDa Ca2+-dependent phospholipid-binding protein (PLBP) in guinea pig alveolar type II cells. PLBP has been suggested to act as a mediator in facilitating and regulating intracellular surfactant assembly and delivery to the plasma membrane of type II cells for secretion into alveolar space. It has been reported that cigarette smoke exposure (CSE) causes a decrease in the surfactant activity in bronchial washings. We have also reported earlier that mainstream (MS) and sidestream (SS) CSE causes desensitization of β-adrenoreceptors in guinea pig alveolar type II cells. Since both Ca2+ and β-adrenoreceptors are involved in surfactant secretion and PLBP is involved in surfactant delivery, it is important to know whether CSE causes any change in the PLBP level in alveolar type II cells. In the present study, we have demonstrated that MS and SS CSE causes a significant increase in the levels of PLBP in alveolar type II cells (107 and 150%, respectively) and in lung lavage (42 and 125%, respectively) in comparison to that in sham control (430 ng/mg protein in alveolar type II cells and 780 ng/mg protein in lung lavage). The mechanism by which smoke exposure causes an elevation in the levels of PLBP in alveolar type II cells and lung lavage remains to be investigated.

In the present study, we generated antibodies in rabbits against two synthetic peptides, one based on peptide sequence from yeast CPT cDNA (position 86 to 98 of the amino acid sequence) and the other from our guinea pig CPT cDNA (it corresponds to amino acid positions 119 to 130 according to yeast CPT gene). The antibody titers were measured by both dot blot analysis and ELISA using Keyhole limpets hemocyanin coupled CPT peptides. The CPT antibody recognized a single band by Western blot analysis of proteins from guinea pig liver mitochondria and microsomes. The molecular weight of the protein recognized by Western blot analysis is close to the predicted molecular weight (46 kDa) of yeast CPT. Further analysis revealed that the antibody inhibited CPT activity in both subcellular fractions in a dose dependent manner, thus confirming the specificity of the antibody against both subcellular CPT.

The correlation of vitamin A with the binding characteristics of peripheral benzodiazepine receptors (PBRs) in testes have been implicated on the basis of findings of involvement of vitamin A in testicular physiology and the abundance of PBRs in testicular tissue. Both vitamin A and PBRs are involved in the control of cell proliferation and differentiation but no data exists regarding the relationship between them. In the present study, we have examined the effects of vitamin A deficiency on the affinity and density of PBRs in testes of guinea pigs. Weanling guinea pigs were divided into three groups: control, pair-fed control and vitamin A deficient. They were fed a complete semipurified diet. The vitamin A deficient diet was similar to the control diet except vitamin A palmitate was omitted. Vitamin A deficiency status was achieved after 90 days of feeding. Binding of [3H]Ro 5-4864, a specific ligand for peripheral benzodiazepine receptors was determined in whole homogenate of testicular tissue. There was a 77% decrease in the receptor density (Bmax) in vitamin A deficient group compared to control. The Bmaxvalues for control, pair-fed control and vitamin A deficient groups were: 12.4 ± 0.4, 8.8 ± 0.2 and 3.0 ± 0.6 pmol/g, respectively. The equilibrium dissociation constant (KD) values were also 86% decreased in the vitamin A deficient group compared to the other groups. The KD values for control, pair-fed control and vitamin A deficient groups were: 3.4 ± 0.7, 2.8 ± 0.5 and 0.5 ± 0.01, respectively. The decrease in the binding characteristics of PBRs in testes due to vitamin A deficiency was accompanied with a corresponding decrease in the levels of testosterone in plasma. These results suggest a close functional relationship of vitamin A with PBRs in testes.

Exposure of 2-chloroethyl ethyl sulfide (CEES) to guinea pigs causes lung injury by infiltration of neutrophils in interstitial lung spaces. A unique MAPK-regulated transcription factor, C/EBP (CCAAT-enhancer-binding protein), regulates the expression of intracellular adhesion molecule-1 (ICAM-1), involved in recruiting neutrophils in lung. The present study was to determine if CEES exposure causes activation of C/EBP, in particular the predominant β-isoform and if so whether it can be prevented by intratracheal delivery of an antioxidant liposome containing N-acetyl cysteine and tocopherols. Lung injury was developed in guinea pigs by intratracheal exposure of CEES (0.5 mg/kg). The antioxidant liposome was given intratracheally 5 min after CEES exposure, and the animals were sacrificed after 30 days. CEES exposure caused a 2.3-fold increase in the activation of C/EBP accompanied with a 45% and 121% increase in the protein level of C/EBP β and ICAM-1, respectively, and this effect was counteracted by the antioxidant liposome.

Toxic oil syndrome (TOS) is caused by ingestion of denatured edible oils. Even though the etiology and pathogenesis of this disease are not fully known, it is quite clear that generation of free radicals caused by ingestion of fatty acid anilides is responsible for the pathogenetic mechanism in many TOS patients. Fatty acid anilides may also alter the free radical status of lungs and erythrocytes; this possibility may shed some light on understanding toxic oil syndrome. The present study describes the effects of oral administration of fatty acid anilides on the activities of major enzymes involved in the oxygen defense systems of lungs and erythrocytes. Feeding fatty acid anilides caused an increase in the superoxide dismutase (SOD) activity in erythrocytes, whereas it caused a decrease in the SOD activity in lungs. GSH-Px activity was not significantly changed in erythrocytes but was decreased in lungs. Although the activity of catalase was increased only by a higher dose in the erythrocytes, it was not affected in the lung at any dosage. Even though the ingestion of fatty acid anilides caused an increase in the SOD activity in the erythrocytes and a decrease in the SOD activity in the lungs, there was an increase in the lipid peroxidation in both cases. The increase in lipid peroxidation in erythrocytes is probably caused by the accumulation of H2O2, and that in the lungs is due to the accumulation of superoxide anion.

beta-Adrenoreceptor has been studied in a clonal capillary endothelial cell line established from the vascular bed of the bovine adrenal medulla. [3H]Dihydroalprenolol ([3H]DHA) binding to the isolated plasma membranes from these cells has demonstrated the presence of beta-adrenoreceptors with two different affinities. The dissociation constants (Kd) have been found to be 0.27 +/- 0.09 x 10(-9) M and 2.96 +/- 0.31 x 10(-9) M, respectively with the corresponding Bmax of 5.1 +/- 0.05 and 70.0 +/- 0.2 pmol/mg protein, respectively. Inhibition of [3H]DHA binding to the beta-receptor by atenolol (a beta 1-antagonist) and ICI 118,551 (a beta 2-antagonist) has suggested that the IC50cor (= Ki) for atenolol and ICI 118,551 for high affinity site are 0.08 +/- 0.03 x 10(-12) M and 0.25 +/- 0.08 x 10(-12) M, respectively. This, therefore, indicates that both atenolol and ICI 118,551 are able to displace the bound ligand effectively but the beta 1-selective antagonist atenolol is 3 times more potent than its beta 2 counterpart, ICI 118,551. Displacement of [3H]DHA binding to the endothelial cell plasma membrane by the agonists isoproterenol, epinephrine and norepinephrine has established a relative order of Ki for these agents as isoproterenol (0.56 +/- 0.19 x 10(-9) M)epinephrine (0.77 +/- 0.26(-9) M)or = norepinephrine (0.71 +/- 0.24 x 10(-9) M) for the high affinity site. The corresponding values for the low affinity site, however, are 4.62 +/- 0.64 x 10(-9) M, 6.21 +/- 0.86 x 10(-9) M and 5.90 +/- 0.82 x 10(-9) M, respectively for the same agonists. Increased intracellular cAMP accompanied with cellular proliferation in the presence of isoproterenol has suggested not only the coupling of beta-adrenoreceptors to the adenylate cyclase system but also its involvement in endothelial cell proliferation.

We have studied the effects of short-term exposure of guinea pigs to cigarette smoke under both mainstream (MS) and sidestream (SS) conditions on the activities of major antioxidant enzymes and lipid peroxidation potential of erythrocytes. The smoke-exposed groups had an increase in the activity of superoxide dismutase (SOD), a decrease in the activities of glutathione peroxidase (GSH-Px) and NADPH generating enzymes, and no change in the activity of catalase. Furthermore, there was a significant increase in the in vitro lipid peroxidation potential of erythrocytes in both MS- and SS-exposed groups. However, the lipid peroxidation potential was higher in the MS-exposed group than that in the SS-exposed group.

It is known that thyroid hormone enhances the biosynthesis of phosphatidylcholine in the lung. The purpose of the present study was to investigate the effects of thyroid hormone on the activity of cholinephosphotransferase, the terminal enzyme in the CDP-choline pathway, in guinea pig lung mitochondria and microsomes. Intramuscular injection of triiodothyronine (T3, 0.25-4 mg/kg body wt) stimulated the activities of both mitochondrial and microsomal enzymes in a dose-dependent manner. However, the stimulation was much more pronounced in the microsomes than in the mitochondria. The stimulatory effect of T3 was blocked by the intraperitoneal injection of both actinomycin D and cycloheximide in the microsomes, whereas in the mitochondria, the hormonal effect was blocked only by cycloheximide. Thus, it is suggested that T3 stimulates not only the nucleocytoplasmic system for the de novo synthesis of the enzyme, but possibly also the regulation of the transport of the synthesized protein into the mitochondria. Furthermore, administration of T3 produced an increase in the uptake and incorporation of [14C]choline into phospholipids of lung slices in vitro. However, this effect was blocked by intraperitoneal injection of both actinomycin D and cycloheximide. Thus, the change in CPT activity by T3 in mitochondria is not reflected by enhanced incorporation of choline into phosphatidylcholine.

It is known that the composition of phospholipids in lung changes with age. The final step in the de novo synthesis of phosphatidylcholine, a major component of lung surfactant, by the CDP-choline pathway, requires the enzyme cholinephosphotransferase (CPT). Even though CPT has earlier been proposed to be located exclusively in the endoplasmic reticulum, we have recently demonstrated its presence also in the mitochondria. We have earlier reported a gestational variation of CPT activity in fetal mitochondria and microsomes. In the present study we examined the subcellular distribution of CPT activity in lung as a function of age. After birth, the microsomal CPT activity continued to increase until adulthood (24 wks of age), thereafter it gradually decreased. On the otherhand, the CPT activity of mitochondria continued to increase with the advancement of age and beyond 72 wks of age, it was approximately 2-fold higher than that of the microsomal fraction.

We report the validation of a reversed-phase gradient HPLC method allowing simultaneous quantification of retinol, retinyl esters, tocopherols and selected carotenoids in lung, liver and plasma of mouse, rat and guinea pig (gp) using a diode array detector. A significant species difference was observed regarding the distribution of retinol and retinyl esters. The levels of total retinol in lung, liver and plasma were in the following order: mouse >> rat > gp; rat >mouse > gp; and gp >> rat > mouse, respectively. Furthermore, comparison studies revealed similarities between the vitamin A profiles of human and gp lung samples.

The purpose of this study was to develop antioxidant liposomes as an antidote for mustard gas-induced lung injury in a guinea pig model. Five liposomes (LIP-1, LIP-2, LIP-3, LIP-4, and LIP-5) were tested with differing levels of phospholipid, cholesterol, phosphatidic acid, tocopherol (alpha, gamma, delta), N-acetylcysteine (NAC), and glutathione (GSH). A single dose (200 microL) of liposome was administered intratracheally 5 min or 1 h after exposure to 2-chloroethyl ethyl sulfide (CEES). The animals were sacrificed either 2 h after exposure (for lung injury study) or 30 days after exposure (for histology study). The liposomes offered 9%-76% protection against lung injury. The maximum protection was with LIP-2 (71.5% protection) and LIP-4 (75.4%) when administered 5 min after CEES exposure. Delaying the liposome administration 1 h after CEES exposure decreased the efficacy. Both liposomes contained 11 mM alpha-tocopherol, 11 mM gamma-tocopherol, and 75 mM NAC. However, LIP-2 contained additionally 5 mM delta-tocopherol. Overall, LIP-2 and LIP-4 offered significant protection by controlling the recruitment of neutrophils, eosinophils, and the accumulation of septal and perivascular fibrin and collagen. However, LIP-2 showed better protection than LIP-4 against the accumulation of red blood cells in the bronchi, alveolar space, arterioles and veins, and fibrin and collagen deposition in the alveolar space. The antifibrotic effect of the liposomes, particularly LIP-2, was further evident by a decreased level of lipid peroxidation and hydroxyproline in the lung. Thus, antioxidant liposomes containing both NAC and vitamin E are an effective antidote against CEES-induced lung injury.

2-Choloroethyl Ethyl Sulfide (CEES) exposure causes inflammatory lung diseases, including acute respiratory distress syndrome (ARDS) and pulmonary fibrosis. This may be associated with oxidative stress, which has been implicated in the desensitization of beta-adrenergic receptors (β-ARs). The objective of this study was to investigate whether lung injury induced by intratracheal CEES exposure (2 mg/kg body weight) causes desensitization of β-ARs. The animals were sacrificed after 7 days and lungs were removed. Lung injury was established by measuring the leakage of iodinated-bovine serum albumin ([125I]-BSA) into lung tissue. Receptor-binding characteristics were determined by measuring the binding of [3H] dihydroalprenolol ([3H] DHA) (0.5–24 nM) to membrane fraction in the presence and absence of DLDL-propranolol (10 μ M). Both high- and low-affinity β-ARs were identified in the lung. Binding capacity was significantly higher in low-affinity site in both control and experimental groups. Although CEES exposure did not change KD and Bmax at the high-affinity site, it significantly decreased both KD and Bmax at low affinity sites. A 20% decrease in β2-AR mRNA level and a 60% decrease in membrane protein levels were observed in the experimental group. Furthermore, there was significantly less stimulation of adenylate cyclase activity by both cholera toxin and isoproterenol in the experimental group in comparison to the control group. Treatment of lungs with 3-isobutyl-1-methylxanthine (IBMX), an inhibitor of phosphodiesterase (PDE) could not abolish the difference between the control group and the experimental group on the stimulation of the adenylate cyclase activity. Thus, our study indicates that CEES-induced lung injury is associated with desensitization of β2-AR. © 2009 Wiley Periodicals, Inc. J Biochem Mol Toxicol 23:59–70, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jbt.20265

Lutein, a dietary carotenoid, is a well known antioxidant. The major source of this carotenoid in humans is diet. We report here the presence of lutein, a dietary carotenoid in several guinea pig tissues (in decreasing order: liver > spleen > lung ≫ testis > kidney > plasma > eye but not in white adipose tissue). The presence of lutein in lung and other tissues may be significant in term of its antioxidant capacity of these organs.

Aim The present study aims to establish that cholinephosphotransferase (CPT), the terminal enzyme for the de novo biosynthesis of phosphatidylcholine (PC), can be used as a biomarker for breast cancer in an animal model. Main methods Breast cancer was induced by intragastric administration of dimethylbenz(a)anthracene (DMBA) in rats. The activity and expression of CPT were compared between normal breast tissues and breast tumors. To establish possible mechanistic model, we looked into other enzymes of PC biosynthesis as well as c-fos protein expression and DNA binding. Key findings CPT enzyme activity and its expression were significantly higher in breast cancer tissues relative to normal breast tissues. Corresponding to the increase in the CPT activity and its expression, c-fos activity and its expression were also increased in breast tumors. Significance The present study suggests that increased CPT activity and expression is associated with DMBA-induced breast cancer development.

We reported earlier that the activation of free-radical-mediated tumor necrosis factor-alpha (TNF-alpha) cascade is the major pathway in the inflammatory lung disease induced by 2-chloroethyl ethyl sulfide (CEES), a mustard gas analog. TNF-alpha induces activating protein 1 (AP-1) activation via phosphorylation of mitogen activated protein kinases (MAPKs). The present study examines the relationship between CEES induced lung injury and MAPKs signaling pathway. Adult guinea pigs received single intratracheal injection of different doses of CEES and were sacrificed at different time points. CEES exposure caused lung injury with evidence of fibrosis. The optimum activation of all members of the MAPKs family (ERK1/2, p38 and JNK1/2) was achieved at 0.5 mg/kg dose and at 1h. No significant change was observed beyond that time point. This led to an activation of AP-1 transcription factors associated with an increase in the protein levels of Fos, activating transcription factor (ATF) and Jun family members. To explore the involvement of AP-1 in cell proliferation, we determined the protein levels of cell cycle protein cyclin D1 and cell differentiation marker proliferating cell nuclear antigen (PCNA). An up regulation of these proteins was observed. Hence it is suggested that CEES exposure causes accumulation of TNF-alpha, which is associated with an activation of MAPK/AP-1 signaling pathway and cell proliferation. Further studies are needed to clarify whether the observed effects are the adaptive responses of the lung or they contribute to the lung injury.