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1.
Cell Death Dis ; 5: e1419, 2014 Sep 11.
Article in English | MEDLINE | ID: mdl-25210802

ABSTRACT

Given the complex heterogeneity of pathological changes occurring in Alzheimer's disease (AD), any therapeutic effort absolutely requires a multi-targeted approach, because attempts addressing only a single event may result ineffective. Palmitoylethanolamide (PEA), a naturally occurring lipid amide between palmitic acid and ethanolamine, seems to be a compound able to fulfill the criteria of a multi-factorial therapeutic approach. Here, we describe the anti-inflammatory and neuroprotective activities of systemic administration of PEA in adult male rats given intrahippocampal injection of beta amyloid 1-42 (Aß 1-42). Moreover, to investigate the molecular mechanisms responsible for the effects induced by PEA, we co-administered PEA with the GW6471, an antagonist of peroxisome proliferator-activated receptor-α (PPAR-α). We found that Aß 1-42 infusion results in severe changes of biochemical markers related to reactive gliosis, amyloidogenesis, and tau protein hyperphosphorylation. Interestingly, PEA was able to restore the Aß 1-42-induced alterations through PPAR-α involvement. In addition, results from the Morris water maze task highlighted a mild cognitive deficit during the reversal learning phase of the behavioral study. Similarly to the biochemical data, also mnestic deficits were reduced by PEA treatment. These data disclose novel findings about the therapeutic potential of PEA, and suggest novel strategies that hopefully could have the potential not just to alleviate the symptoms but also to modify disease progression.


Subject(s)
Alzheimer Disease/prevention & control , Ethanolamines/administration & dosage , Neuroprotective Agents/administration & dosage , Palmitic Acids/administration & dosage , Alzheimer Disease/drug therapy , Alzheimer Disease/metabolism , Alzheimer Disease/pathology , Amides , Animals , Disease Models, Animal , Gliosis , Humans , Male , PPAR alpha/genetics , PPAR alpha/metabolism , Rats , Rats, Sprague-Dawley
2.
Anticancer Res ; 19(1A): 589-96, 1999.
Article in English | MEDLINE | ID: mdl-10226603

ABSTRACT

BACKGROUND: Several natural products have been found to exhibit a chemopreventive activity both in in vivo and in vitro experimental systems. Among them, protease inhibitors seem to play a key role in the regulation of growth and phenotypic expression of transformed cells as well as in the regulation of the late events of carcinogenesis. We evaluated the effect of antipain (AP), a natural protease inhibitor, on chemically induced BALB/c 3T3 cell transformation, on invasion and chemotactic motility of transformed cells and on their gelatinase expression. METHODS: BALB/c 3T3 cells were plated and exposed to 2.5 micrograms/ml 3-MCA or 50 micrograms/ml, 1,2-DBE. The effect of a non-cytotoxic dosage of AP (10 microM) was studied by: a) pretreating cells with AP for 48 hours before the carcinogen exposure; b) adding AP simultaneously to the carcinogen treatment; c) chronic addition of AP at each medium change throughout the experimental duration. The effectiveness of the treatment was analysed as the ability to reduce or inhibit the occurrence of transformed foci. Modulation of the invasive phenotype by anti-transforming dosages of AP was evaluated by in vitro Matrigel invasion assay. Gelatin zymography was performed in order to assess AP regulation of proteolytic enzymes, such as metalloproteases, involved in invasion and metastasis. RESULTS: AP treatment can reduce the transformation rate both in 3-MCA- and 1,2-DBE-initiated cells. Its effectiveness depends on the administration schedule, and chronic addition seems to be the most effective treatment. The concentration of AP, which is effective in the antitransformation assay, is not able to significantly affect the migration and invasion of chemically transformed cells or their gelatinase activity. CONCLUSIONS: AP can suppress chemically induced BALB/c 3T3 cell transformation through mechanisms which do not involve modulation of the invasive phenotype.


Subject(s)
Anticarcinogenic Agents/pharmacology , Antipain/pharmacology , Cell Transformation, Neoplastic/drug effects , Protease Inhibitors/pharmacology , 3T3 Cells , Animals , Mice
3.
J Vasc Surg ; 29(5): 894-901, 1999 May.
Article in English | MEDLINE | ID: mdl-10231641

ABSTRACT

OBJECTIVE: The outcome of crossover axilloaxillary bypass grafting in patients with stenosis or occlusion of the innominate or subclavian arteries was investigated. METHODS: The study was designed as a retrospective clinical study in a university hospital setting with 61 patients as the basis of the study. Fifty-eight patients (95.1%) had at least two risk factors or associated medical illnesses for atherosclerosis, and 35 patients (57.4%) had concomitant carotid artery stenosis that necessitated a staged procedure in 12 patients (19.7%). The patients underwent a total of 63 crossover axilloaxillary bypass grafting procedures. Demographics, risk factors and associated medical illnesses, preoperative symptoms and angiographic data, blood flow inversion in the vertebral artery, concomitant carotid artery disease, graft shape, caliber and material, and intraoperative and postoperative complications were studied to assess the specific influence in determining the outcome. RESULTS: One postoperative death (1.6%), four early graft thromboses (6.2%), and six minor complications (9. 8%) occurred. The overall mortality and morbidity rates were 1.6% and 16.1%, respectively. During the follow-up period (mean, 97.3 +/- 7.9 months), we observed five graft thromboses (8.3%). Primary and secondary patency rates at 5 and 10 years were 86.5% and 82.8% and 88.1% and 84.3%, respectively. Overall, two patients (3.3%) had recurrence of upper limb symptoms and none had recurrence of symptoms in the carotid or vertebrobasilar territory. The 5-year and 10-year symptom-free interval rates were 97.7% and 93.5%, respectively. Nine patients (15%) died of unrelated causes. The 5-year and 10-year survival rates were 93.2% and 67.3%, respectively. Multivariate analysis showed that no specific variables exerted an influence in the short-term and long-term results and the outcome. CONCLUSION: The optimal outcome of axilloaxillary bypass grafting supports its use as the most valuable surgical alternative to transthoracic anatomic reconstructions for innominate lesion, long stenosis of the subclavian artery, and short subclavian artery stenosis associated with ispilateral carotid artery lesions.


Subject(s)
Arterial Occlusive Diseases/surgery , Brachiocephalic Trunk , Subclavian Artery , Adult , Aged , Arm/blood supply , Constriction, Pathologic , Female , Humans , Ischemia/surgery , Life Tables , Male , Middle Aged , Retrospective Studies , Treatment Outcome , Vascular Patency
4.
Ann Thorac Surg ; 59(5): 1107-12, 1995 May.
Article in English | MEDLINE | ID: mdl-7733705

ABSTRACT

The purpose of this study was to evaluate the use of retrograde cerebral perfusion via the superior vena cava during profound hypothermia and circulatory arrest (CA) in pigs. In three groups of 5 pigs each, group A (control) underwent cardiopulmonary bypass and normothermic CA for 1 hour, group B underwent cardiopulmonary bypass, profound hypothermia, and CA (15 degrees C nasopharyngeal) for 1 hour, and group C underwent the same procedure as group B plus retrograde cerebral perfusion. In group A none awoke. In group B, 2 of 5 did not awake and 3 of 5 awoke unable to stand, 2 with perceptive hind limb movement and 1 moving all extremities. In group C all awoke, 4 of 5 able to stand and 1 of 5 unable to stand but moving all limbs. In neurologic evaluation group B had significantly lower Tarlov scores than group C (p = 0.0090). Group B mean wake-up time, plus or minus standard error of the mean, was 124.6 +/- 4.6 minutes versus 29.2 +/- 5.1 in group C (p = 0.0090). In group B late phase CA cerebral blood flow dropped 30.9% +/- 4.8%, but in group C it rose 24.7% +/- 9.3% (p = 0.0007, pooled variance t test, two-tailed). In group B late phase CA brain oxygenation decreased 46.0% +/- 13.9% but it increased 26.1% +/- 5.4% in group C (p = 0.0013). This difference was reduced somewhat during rewarming (B, -21.2% +/- 14.9%; C, 16.4% +/- 4.7%; p = 0.043). Group B rewarming jugular venous O2 saturation was 30.8% +/- 2.5% versus 56.0% +/- 4.4% in group C (p = 0.0011). We conclude that in pigs retrograde cerebral perfusion combined with profound hypothermia during CA significantly reduces neurologic dysfunction, providing superior brain protection.


Subject(s)
Cerebrovascular Circulation , Heart Arrest, Induced , Hypothermia, Induced , Animals , Blood Flow Velocity , Brain/metabolism , Brain/pathology , Carbon Dioxide/blood , Cardiopulmonary Bypass , Central Nervous System Diseases/etiology , Hydrogen-Ion Concentration , Jugular Veins , Laser-Doppler Flowmetry , Oxygen/blood , Oxygen/metabolism , Swine , Vena Cava, Superior
5.
Minerva Cardioangiol ; 43(5): 185-90, 1995 May.
Article in English | MEDLINE | ID: mdl-7478041

ABSTRACT

Coronary artery disease accounts for most of the early and late mortality and morbidity associated with vascular surgery. Cardiac pre-operative evaluation is mandatory for the assessment of cardiac risk. The aim of this study is to compare dipyridamole scintigraphy with 99mTc-MIBI (MIBI-dipy) and dipyridamole echocardiography (ECHO-dipy) and to evaluate their capability in identifying cardiac risk for strong events such as death, unstable angina or myocardial infarction. METHODS. Sixty consecutive patients (mean age 67 +/- 7) were enrolled. 52 performed ECHO-dipy, 51 MIBI-dipy. 40 patients went to aorto-femoral or aorto-iliac graft replacement and 15 to vascular angioplasty. Five patients did not undergo surgery. RESULTS. Eighteen patients (30%) had stress defects and 9 patients also rest defects with MIBI-dipy. Six patients new asinergic areas at ECHO-dipy. Three pts died in the first year follow-up for a cerebrovascular event, a myocardial infarction and a sudden death respectively. Sensitivity and specificity, positive and negative predictive value were 100%, 69%, 16%, 100% for MIBI-dipy and 66%, 94%, 40%, 98% for ECHO-dipy. CONCLUSIONS. As other authors reported, stress scintigraphy is a pre-operative test showing high sensitivity but with no satisfying specificity. Stress echocardiography, in our population, can produce a good negative predictive value. It is a less expensive and widespread clinical tool useful in the evaluation of preoperative patients. Its positive predictive power is not satisfying but it is shared with all non-invasive pre-operative tests available now.


Subject(s)
Dipyridamole , Echocardiography/methods , Peripheral Vascular Diseases/diagnosis , Technetium Tc 99m Sestamibi , Vascular Surgical Procedures , Aged , Aged, 80 and over , Aortic Aneurysm, Abdominal/diagnosis , Aortic Aneurysm, Abdominal/surgery , Coronary Disease/diagnosis , Coronary Disease/surgery , Female , Humans , Male , Middle Aged , Peripheral Vascular Diseases/surgery , Postoperative Complications , Preoperative Care , Vasodilator Agents
6.
Jpn J Cancer Res ; 86(2): 168-73, 1995 Feb.
Article in English | MEDLINE | ID: mdl-7730140

ABSTRACT

The two-stage transformation assay increases the sensitivity of cells to chemicals and permits detection of carcinogens acting as initiating agents. 1,2-Dibromoethane, a representative halogenated aliphatic, has been tested in the two-stage BALB/c 3T3 cells transformation test at dosage from 16 microM to 128 microM. This dose range is much lower than those previously found efficient in transforming BALB/c 3T3 cells. Apart from the lowest dose, which induced borderline effects, all the other assayed dosages appeared to induce heritable changes in the target cells. The initiated cells were revealed as fully transformed foci both in the combination with a chronic promoting treatment and also by allowing cells to perform more rounds of cell replication. The results clearly show that 1,2-dibromoethane can act as an initiator of cell transformation.


Subject(s)
Carcinogens/pharmacology , Cell Transformation, Neoplastic/chemically induced , Ethylene Dibromide/pharmacology , 3T3 Cells , Animals , Cell Line, Transformed , Cell Survival/drug effects , Colony-Forming Units Assay , Mice , Mice, Inbred BALB C
7.
J Vasc Surg ; 20(3): 434-44; discussion 442-3, 1994 Sep.
Article in English | MEDLINE | ID: mdl-8084037

ABSTRACT

PURPOSE: This prospective study evaluated the possible prevention of postoperative neurologic deficit in patients at high risk with thoracoabdominal aortic aneurysms (TAAA), types I and II, by use of perioperative cerebrospinal fluid drainage and distal aortic perfusion. METHODS: Between September 18, 1992, and August 8, 1993, 45 consecutive patients underwent TAAA repair (14 type I, 31 type II). Thirty-six were men and nine were women. The median age was 63 years (range 28 to 88). Twenty-four of 45 patients (53%) had dissection and 17 of 45 (38%) had prior proximal aortic replacement. All patients underwent perioperative cerebrospinal fluid drainage and distal aortic perfusion. Median aortic clamping time was 42 minutes. Thirty-five of 45 patients (78%) underwent intercostal artery reattachment. RESULTS: The 30-day survival rate was 96% (43 of 45 patients). Early neurologic deficit occurred in two of 45 patients (4%), and late neurologic deficit also occurred in two of 45 patients (4%). We compared the neurologic deficit of our current group of 45 patients with the data of a previously unpublished study of 112 patients also from this center. Total neurologic deficit for the current group was four of 45 (9%) versus the previous group of 35 of 112 (31%) with a p value of 0.0034 (Pearson chi-square test). Neurologic deficit for patients with type I TAAA was 0 of 14 (0%) versus 15 of 73 (21%) (p = 0.062); for patients with type II TAAA 4 of 31 (13%) versus 20 of 39 (51%) (p = 0.0008). In patients with aortic dissection, neurologic deficit was 3 of 24 (12%) versus 9 of 32 (28%) (p = 0.0304); no dissection was 1 of 21 (5%) versus 26 of 80 (32%) (p = 0.011). For aortic clamp times less than 45 minutes, neurologic deficit was 1 of 24 (4%) versus 14 of 68 (21%) (p = 0.061); for aortic clamp times equal to or greater than 45 minutes, neurologic deficit was 3 of 21 (14%) versus 21 of 44 (48%) (p = 0.0090). CONCLUSION: Neurologic deficit in patients treated for types I and II TAAA was reduced significantly by perioperative cerebral spinal fluid drainage and distal aortic perfusion.


Subject(s)
Aortic Aneurysm, Abdominal/surgery , Aortic Aneurysm, Thoracic/surgery , Aortic Dissection/surgery , Cerebrospinal Fluid Shunts , Infusion Pumps, Implantable , Nervous System Diseases/prevention & control , Postoperative Complications/prevention & control , Reperfusion , Adult , Aged , Aged, 80 and over , Aortic Dissection/complications , Aortic Dissection/mortality , Aortic Aneurysm, Abdominal/complications , Aortic Aneurysm, Abdominal/mortality , Aortic Aneurysm, Thoracic/complications , Aortic Aneurysm, Thoracic/mortality , Constriction , Drainage , Female , Humans , Incidence , Intraoperative Care , Male , Middle Aged , Multivariate Analysis , Nervous System Diseases/epidemiology , Nervous System Diseases/etiology , Postoperative Care , Postoperative Complications/epidemiology , Postoperative Complications/etiology , Prospective Studies , Regression Analysis , Risk Factors , Survival Rate
9.
Minerva Chir ; 47(15-16): 1293-303, 1992 Aug.
Article in Italian | MEDLINE | ID: mdl-1407631

ABSTRACT

The Authors propose an organizational model for a surgical day hospital program, which is being used for a pilot day surgery unit in the I Department of Surgery of the Rome University "La Sapienza". The program requires little capital investment, as it is closely linked, geographically and administratively, to the main surgical unit, and uses the present staff, facilities and support services. The model is based on a computerized LAN (Local Area Network), providing fast recording, scheduling, management and trannsfer of medical data for each patient. The present situation is reported in detail. Data from the authors' outpatient department for 1988, have been recorded and elaborated. The results show a low use of surgical day care, limited to minor surgical procedures, and with not a single operation performed under general anesthesia. The authors hope to see a growth in the use of day surgery and a more selective use of inpatient care.


Subject(s)
Ambulatory Surgical Procedures , Day Care, Medical , Adolescent , Adult , Aged , Aged, 80 and over , Child , Child, Preschool , Day Care, Medical/organization & administration , Female , Humans , Infant , Italy , Male , Middle Aged
10.
Cancer Lett ; 64(2): 145-53, 1992 Jun 15.
Article in English | MEDLINE | ID: mdl-1611598

ABSTRACT

By using in vitro two-stage BALB/c 3T3 cell transformation assay, we have tested the effect of promoting treatment with tetradecanoylphorbol acetate (TPA) on transformation induced by 1,1,2,2-tetrachloroethane (1,1,2,2-TTCE). Cells were treated with subeffective or transforming concentrations of 1,1,2,2-TTCE in the presence of an S9-mix activating system, followed by TPA promoting treatment. The transforming activity of 1,1,2,2-TTCE is evident only by reseeding confluent cells and allowing additional rounds of cell replications in the amplification test. Treatment with TPA leads to a marked transformation yield in all plates scored even at the lowest assayed dosage of 1,1,2,2-TTCE, without performing amplification of transformation.


Subject(s)
Cell Transformation, Neoplastic/chemically induced , Ethane/analogs & derivatives , Hydrocarbons, Chlorinated/toxicity , 3T3 Cells/drug effects , 3T3 Cells/ultrastructure , Animals , Cell Division/drug effects , Dose-Response Relationship, Drug , Ethane/toxicity , Liver Extracts/pharmacology , Mice , Mice, Inbred BALB C , Sister Chromatid Exchange/drug effects , Tetradecanoylphorbol Acetate/pharmacology
11.
Res Commun Chem Pathol Pharmacol ; 76(2): 192-208, 1992 May.
Article in English | MEDLINE | ID: mdl-1376481

ABSTRACT

Trichloroethylene was covalently bound in vivo to DNA, RNA and proteins of rat and mouse organs 22 hr after ip injection. The covalent binding index values of rat and mouse liver DNA classify trichloroethylene as a weak initiator. Labeling of RNA and proteins from various organs of both species was higher than that of DNA. In vitro, trichloroethylene was bioactivated by microsomal fractions dependent on cytochrome P450, mainly from liver of both species, to intermediate(s) capable of binding to exogenous DNA. No particular species-specific difference was evident except for mouse lung microsomes which were more efficient than rat lung microsomes. GSH-transferases capable of bioactivating P450-dependent were present in mouse lung microsomes and in liver microsomes of both species. These data, along those previously reported, provide sufficient evidence for a weak ability of TCY to interact covalently with DNA.


Subject(s)
DNA/drug effects , Proteins/drug effects , RNA/drug effects , Trichloroethylene/pharmacology , Animals , Cattle , Cytochrome P-450 Enzyme System/metabolism , Glutathione Transferase/metabolism , Mice , Microsomes/drug effects , Microsomes/enzymology , NADP/metabolism , Rats , Species Specificity
12.
Surg Gynecol Obstet ; 173(3): 175-8, 1991 Sep.
Article in English | MEDLINE | ID: mdl-1925875

ABSTRACT

The gross findings of 49,144 autopsies performed at two major hospitals in Rome were reviewed. There were 297 patients who were found to have atherosclerotic abdominal aortic aneurysm (AAA). The aneurysm was intact in 220 (74 per cent) and ruptured in 77 (26 per cent). The occurrence of aneurysm rupture was correlated to 17 variables by univariate and multivariate statistical analysis. Covariates found to be independently predictive of the rupture of AAA were the size of the aneurysm (p less than 0.001), arterial hypertension (p less than 0.001) and the presence of bronchiectasis (p less than 0.025.). Over-all, bronchiectasis was more common among patients with AAA than in the age-adjusted and sex-adjusted control population. The simultaneous presence of bronchiectasis and AAA suggests the presence of some inherited or acquired tendency to have ectasia of the connective tissue, aneurysm formation and rupture development.


Subject(s)
Aortic Rupture/epidemiology , Adult , Aged , Aged, 80 and over , Analysis of Variance , Aorta, Abdominal , Autopsy , Female , Humans , Male , Middle Aged , Multivariate Analysis , Risk Factors
13.
Tumori ; 77(4): 285-90, 1991 Aug 31.
Article in English | MEDLINE | ID: mdl-1746048

ABSTRACT

Chloroform was bound covalently to DNA, RNA and proteins of rat and mouse organs in vivo after i.p. injection. Covalent Binding Index values of rat and mouse liver DNA classify chloroform as a weak initiator. Labelings of RNA and proteins from various organs of both species were higher than that of DNA. In an in vitro cell-free system, chloroform was bioactivated by cytochrome P450-dependent microsomal fractions, by cytosolic GSH-transferases from rat and mouse liver, and particularly by the latter enzymes from mouse lung. This observation suggests that GSH plays a role in the binding of chloroform metabolites to DNA. The presence of both microsomal and cytosolic enzymatic systems in the standard incubation mixture generally led to an additive or synergistic bioactivating effect for rat and mouse, respectively.


Subject(s)
Chloroform/metabolism , DNA/metabolism , Animals , Biotransformation , DNA Damage , Male , Mice , Microsomes, Liver/metabolism , Rats , Rats, Inbred Strains
14.
Minerva Chir ; 46(13-14): 777-9, 1991 Jul.
Article in Italian | MEDLINE | ID: mdl-1961607

ABSTRACT

A young woman of 34 years old had an asymptomatic intrahepatic mass. The histological diagnosis, performed after a right lobe hepatectomy, was of leiomyoma of the liver.


Subject(s)
Leiomyoma/surgery , Liver Neoplasms/surgery , Adult , Female , Hepatectomy , Humans , Leiomyoma/pathology , Liver/pathology , Liver Neoplasms/pathology
15.
Res Commun Chem Pathol Pharmacol ; 71(2): 209-18, 1991 Feb.
Article in English | MEDLINE | ID: mdl-1710814

ABSTRACT

14C-methyl parathion was covalently bound to DNA, RNA and proteins of various rat and mouse organs 22 hr after i.p. injection. Covalent binding index (CBI) to liver DNA was low in both species and typical of weak initiators. The labelings of RNA and proteins from different organs of both species was slightly higher than DNA binding. No interaction with brain nucleic acids was observed (CBI detection limit: 2.8). The in vitro enzyme-mediated interaction of methyl parathion with calf thymus DNA was mainly performed by rodent liver microsomes and, to a lesser extent, by microsomes from mouse kidney and lung whereas brain microsomes were inefficient. Activation of methyl parathion by cytosolic fractions from different organs of both species to form(s) capable of binding to DNA was negligible. When microsomes and cytosolic fractions from rodent liver and lung or mouse kidney were simultaneously present in the incubation mixture, a synergistic effect in catalyzing DNA binding was observed. The extent of DNA binding was reduced by adding SKF 525-A to the microsomal standard incubation mixture, whereas it was enhanced by adding GSH to liver or lung murine microsomes or to mouse kidney microsomes. These results suggest that methyl parathion is bioactivated by P450-dependent microsomal mixed function oxidase system and by microsomal GSH-transferases. By contrast, cytosolic GSH- transferases play a detoxificant role in the metabolism of this compound.


Subject(s)
DNA Damage , Methyl Parathion/toxicity , Animals , Cytosol/drug effects , Cytosol/metabolism , DNA/metabolism , In Vitro Techniques , Male , Methyl Parathion/metabolism , Mice , Mice, Inbred BALB C , Microsomes/drug effects , Microsomes/metabolism , Phenobarbital/pharmacology , Protein Binding , Pyridines/pharmacology , RNA/metabolism , Rats , Rats, Inbred Strains
16.
Toxicol Lett ; 54(2-3): 121-7, 1990 Dec.
Article in English | MEDLINE | ID: mdl-1701931

ABSTRACT

1,4-Dibromobenzene (1,4-DBB) was covalently bound to DNA from liver, kidney, lung and stomach of mice after intraperitoneal administration. The covalent binding index (CBI) value (23 in mouse liver) was typical of weak initiators. On the contrary, no interaction with DNA from rat organs was observed (CBI detection limit: 1.3-2.6). The in vitro interaction of 1,4-DBB with calf thymus DNA was mediated mainly by microsomes, especially those from liver of both species and from mouse lung. Mouse subcellular fractions were more active then rat subcellular fractions. Unlike liver cytosol, subcellular cytosolic fractions from lung, kidney and stomach were capable of bioactivating 1,4-DBB, although to a lesser extent than liver microsomes. Both cytochrome P-450 and GSH-transferases are involved in 1,4-DBB bioactivation.


Subject(s)
Bromobenzenes/metabolism , DNA/metabolism , Phenobarbital/pharmacology , RNA/metabolism , Animals , Binding Sites , Bromobenzenes/toxicity , Drug Interactions , Gastric Mucosa/metabolism , Injections, Intraperitoneal , Kidney/metabolism , Liver/metabolism , Lung/metabolism , Male , Mice , Mice, Inbred BALB C , Rats , Rats, Inbred Strains
17.
Tumori ; 76(4): 339-44, 1990 Aug 31.
Article in English | MEDLINE | ID: mdl-1697992

ABSTRACT

Twenty-two hours after i.p. injection into male Wistar rats and BALB/c mice, 1,2-dichlorobenzene (1,2-DCB) was covalently bound to DNA, RNA, and proteins of liver, kidney, lung and stomach. The covalent binding index to liver DNA was typical of carcinogens classified as weak initiators. The enzyme-mediated in vitro interaction of 1,2-DCB with calf thymus DNA of synthetic polyribonucleotides was carried out by a microsomal mixed-function oxidase system and microsomal GSH-transferases, which seemed to be effective only in liver and lung of rat and mouse. Cytosolic GSH-transferases played a minor role in 1,2-DCB bioactivation. The latter finding provides the first evidence of 1,2-DCB genotoxicity in mammalian cells. The type of halide, the number of halosubstituents and their spatial disposition on the benzene ring are the major determinants of halobenzenes activability to intermediate(s) capable of interacting covalently with DNA and other macromolecules in biologic systems.


Subject(s)
Chlorobenzenes/metabolism , DNA/metabolism , Insecticides/metabolism , Microsomes/metabolism , RNA/metabolism , Animals , In Vitro Techniques , Male , Mice , Mice, Inbred BALB C , Microsomes, Liver/metabolism , Protein Binding , Proteins/metabolism , Rats , Rats, Inbred Strains , Structure-Activity Relationship
18.
Tumori ; 75(4): 305-10, 1989 Aug 31.
Article in English | MEDLINE | ID: mdl-2479159

ABSTRACT

Twenty-two hours after i.p. injection to male Wistar rats and BALB/c mice para-dichlorobenzene (p-DCB) is bound covalently to DNA from liver, kidney, lung and stomach of mice but not of rats. DNA adducts in mouse liver are repaired in seventy-two hours. The covalent binding index value, calculated on the labelling of mouse liver DNA, classifies p-DCB as a weak initiator with an oncogenic activity lower than that of chlorobenzene. The labelling of RNA and proteins from the different organs of both species is, however, low. In vitro interaction with calf thymus DNA mediated by mouse and rat microsomes from liver and lung did occur. Binding extent was strongly reduced by addition of 2-diethylaminoethyl-2,2-diphenylvalerate hydrochloride (SKF 525-A) to the microsomal standard incubation mixture, whereas it was enhanced by adding GSH. Cytosolic fractions from kidney and lung were able to induce binding of p-DCB to DNA to a lower extent with respect to microsome-mediated binding. These results indicate that microsomal mixed function oxidase system and microsomal GSH-transferases can be involved in overall activating metabolism whereas cytosolic GSH-transferases play a minor role. This study, which is a part of a structure-activity relationship approach on benzene and its haloderivatives, provides the first evidence of genotoxicity of p-DCB in mammalian cell. It allows to partly explain variations of susceptibility of different species to hepatocarcinogenesis and of hepatotoxicity of different isomers.


Subject(s)
Chlorobenzenes/metabolism , DNA/metabolism , Insecticides/metabolism , Mutagens , Animals , Biotransformation , Chlorobenzenes/toxicity , Glutathione/pharmacology , In Vitro Techniques , Male , Mice , Mice, Inbred BALB C , RNA/metabolism , Rats , Rats, Inbred Strains , Species Specificity , Structure-Activity Relationship
19.
Environ Health Perspect ; 82: 259-66, 1989 Jul.
Article in English | MEDLINE | ID: mdl-2477240

ABSTRACT

The dose-response relationship of the benzene covalent interaction with biological macromolecules from rat organs was studied. The administered dose range was 3.6 x 10(7) starting from the highest dosage employed, 486 mg/kg, which is oncogenic for rodents, and included low and very low dosages. The present study was initially performed with tritium-labeled benzene, administered by IP injection. In order to exclude the possibility that part of the detected radioactivity was due to tritium incorporated into DNA from metabolic processes, 14C-benzene was then also used following a similar experimental design. By HPLC analysis, a single adduct from benzene-treated DNA was detected; adduct identification will be attempted in the near future. Linear dose-response relationship was observed within most of the range of explored doses. Linearity was particularly evident within low and very low dosages. Saturation of benzene metabolism did occur at the highest dosages for most of the assayed macromolecules and organs, especially in rat liver. This finding could be considered as indicative of the dose-response relationship of tumor induction and could be used in risk assessment.


Subject(s)
Benzene/metabolism , DNA/metabolism , Protein Binding , RNA/metabolism , Animals , Chromatography, High Pressure Liquid , Dose-Response Relationship, Drug , Gastric Mucosa/metabolism , Kidney/metabolism , Liver/metabolism , Lung/metabolism , Male , Rats , Rats, Inbred Strains , Spleen/metabolism , Tissue Distribution
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