Dietary supplementation with omega-3 essential fatty acids results in the production of uniqe 5-lipoxygenase and cyclooxygenase products which are biologically less active and may inhibit the production, or actions, of the eicosanoids produced when arachidonic acid is the substrate for 5-lipoxygenase and cyclooxygenase, rather than omega-3 essential fatty acids. Since airway inflammation may play a central role in the pathophysiology of asthma, we studied the effect of omega-3 essential fatty acids on bronchial responsiveness in 7 atopic patients suffering from seasonal asthma due to airborne allergens, and positive to intracutaneous skin reaction to two or more allergens. Bronchial responsiveness to ultrasonically nebulized distilled water (UNDW) was determined 30 days from the initial ingestion of 3 g/day of omega-3 essential fatty acids and 30 days after stopping dietary supplementation. Flow volume curves and Raw were recorded before the provocation test, at the end of inhalation, and at 10-, 20-, 30- and 60-min intervals. The maximum fall in forced expiratory volume in 1 s (FEV1) and the maximum increase in airway resistance (Raw) were chosen as the main outcome parameters. After 30 days of dietary supplementation, bronchial responsiveness to UNDW was significantly improved (in fact maximum fall in FEV1 was -11% vs. -28% before treatment, and maximum increase in Raw was +37% vs. +265% before treatment). The challenge test repeated 30 days after stopping dietary supplementation was the same as that recorded before treatment. The present data strongly suggest the hypothesis that dietary supplementation with omega-3 essential fatty acids could decrease bronchial hyperreactivity in atopic patients.
Doxophylline, or 2-(7'-theophyllinemethyl)1,3-dioxolane, is a theophylline derivative which has shown interesting bronchodilating activity, and it appears to determine few adverse effects. The aim of the present investigation was to evaluate clinical therapeutic effects of the drug in the treatment of 2 groups of patients suffering from moderate to severe chronic obstructive pulmonary disease differing in acute response to the inhaled beta 2-agonist salbutamol and to compare changes of lung function tests to serum concentration of doxophylline. We studied 67 patients with chronic obstructive pulmonary disease (median age 63 years, 9 females and 58 males) who were all clinically stable at the time of the study. Patients were separated into 2 groups on the basis of their reaction to inhalation of 200 micrograms of salbutamol: those with an increased FEV1 of more than 20% from baseline value (group 1), and those with no increase (group 2). Doxophylline was administered orally at the dose of 400 mg 3 times daily. Serum levels of doxophylline were determined by high-pressure liquid chromatography. Spirometry and blood gas analysis were performed before and 10 days after treatment. Four patients stopped drug assumption because of side effects (3 for dyspepsia and 1 for anxiety). In group 1 (34 patients), a significant increase in SVC, FVC, FEV1, FEF 25-75% and PEFR was observed. In group 1 (29 patients), only PEFR significantly increased. No modifications in blood gas analysis were observed. The mean serum level of doxophylline was 14 micrograms/ml in group 1 and 9 micrograms/ml in group 2: the difference was statistically significant. The relation between serum levels of doxophylline and FVC showed an increase in the parameter up to the concentration of 12-13 micrograms/ml, after which a plateau phase was observed. On the basis of our data, doxophylline appears to have an interesting bronchodilating effect in patients responsive to the inhaled beta 2-agonist salbutamol. The lower limit of the therapeutic range seems to be 12-13 micrograms/ml. The upper limit of the therapeutic range was not determined because it was not possible to obtain serum samples when side effects occurred.
Lung function tests, including spirometry, and pulmonary transfer factor for carbon monoxide (TLCO), serum angiotensin-converting enzyme (sACE), serum copper (sCU++) and serum procollagen III peptide (sPIIIP) were measured in 20 patients with metastatic testicular carcinoma, before and after treatment with cisplatin, bleomycin, vinblastine or etoposide. A significant decrease of TLCO, total lung capacity and vital capacity was observed at the end of the treatment. No recovery of pulmonary function had taken place 2 yrs after the last dose of bleomycin. This result suggests that bleomycin-induced lung damage is not completely reversible. Serum angiotensin-converting enzyme, remained unmodified, whilst sPIIIP was found to be significantly increased at the end of chemotherapy, but normal 2 yrs after the completion of chemotherapy. Serum Cu++ showed a tendency to decline. No significant correlation was found between sACE, sCu++ and sPIIIP and lung function tests in the follow-up period. These results question the possibility that these markers could be useful indicators of bleomycin-induced lung damage.
Aims We studied cardiac and pulmunaty function in 22 patients affected by in transit metastases from cutaneous melanoma and metastases from soft tissue sarcoma of the limbs and treated with isolation perfusion in extracorporeal circulation with rTNF alpha at doses ranging from 0.5 to 4 mg/m2 in mild hyperthermia. Patients and methods All patients experienced a septic-like shock syndrome of variable severity: this feature lasted from 24 to 72 h and was controlled by the infusion of dopamine. Seventeen patients suffered from respiratory insufficiency, which required assisted ventilation (7 cases mechanical ventilation for 1 day, 8 cases for 2 days, and 2 cases synchronized intermittent mandatory ventilation). Results Spirometrie parameters recorded 7-15 days after treatment did not change from baseline values. In contrast, lung transfer factor for carbon monoxide significantly declined in a dose dependent fashion. Conclusions Our data confirm that rTNF alpha administered by isolation perfusion technique induces systemic cardiovascular and pulmonary side effects. Further studies are required to better define time course and reversibility of impaired pulmunary function.
We studied pulmonary function in 22 patients affected by in-transit metastases from cutaneous melanoma and metastases from soft tissue sarcoma of the limbs who were treated with isolation perfusion in extracorporeal circulation with rTNF alpha at doses ranging from 0.5 to 4 mg/m2 in mild hyperthermia. Seventeen patients suffered from respiratory insufficiency which required assisted ventilation (7 mechanical ventilation for 1 day, 8 for 2 days and 2 patients on synchronized intermittent mandatory ventilation). Spirometric parameters recorded 7 to 15 days after treatment did not change from baseline values; in contrast, lung transfer factor for carbon monoxide significantly declined in a dose dependent fashion. These data confirm that rTNF alpha administered by isolation perfusion technique induces pulmonary side effects. Further studies are required to better define time course and reversibility of impairment in pulmonary function.
The aim of the present investigation was to evaluate the type and the incidence of cardiac arrhythmias and ischaemic events in patients suffering from testicular cancer and submitted to combination chemotherapy with cisplatin, bleomycin and vinblastine (PVB) or etoposide (PEB). Forty-seven patients took part in the study; 23 were treated with PVB and 24 with PEB. Holter monitoring was performed in each patient before chemotherapy and on the 1st, 2nd and 5th day of the first cycle of drug administration. The results showed that combination chemotherapy with PVB or PEB was accompanied by the appearance of, or an increase in, the incidence of supraventricular ectopic beats. No significant difference was found between the two groups. No significant conduction disturbances were recorded. These results show that combination chemotherapy with PVB or PEB, at least during the first cycle, has no significant ventricular arrhythmogenic or ischaemic potency in young people with no history of cardiac disease.
The aim of the present investigation was to evaluate lung toxicity in 15 patients affected by metastatic melanoma of different sites, and treated with recombinant interleukin-2 (rIL-2) plus lymphokine-activated killer (LAK) cells The treatment regimen included a first and a second course of rIL-2, separated by four consecutive daily leukaphereses. Autologous LAK cells were reinfused during the second course. Lung function was monitored before and after each rIL-2 administration. In the 12 patients who could be followed until completion of the therapy, spirometric parameters and transfer factor of the lungs for carbon monoxide (TLCO) decreased significantly during the first rIL-2 course, remained stable during leukapheresis, and declined significantly further during the second rIL-2 course. In the second phase, chest radiography documented some degree of pulmonary oedema, ranging from interstitial oedema to frank pulmonary oedema. A significant dose-dependent correlation was found between the cumulative rIL-2 dose and the decline in TLCO in the first course of therapy. Moreover, patients who developed symptomatic respiratory insufficiency (World Health Organisation grade III or IV) during the second course of therapy received a higher number of LAK cells than those who did not. The data support the hypothesis that LAK cells have an additional toxic effect on the lung.
In 30 patients affected by testicular non-seminomatous cancer we evaluated pulmonary function tests before and after bleomycin-including combination chemotherapy. We paid particular attention to changes in diffusing lung capacity (DCO) and its two components, namely diffusing capacity of the alveolar-capillary membrane (Dm) and pulmonary capillary blood volume (Vc). In the same patients we also evaluated the behaviour of serum procollagen III aminopeptide (sP-III-P), assumed to be a biochemical equivalent to Dm, and of serum angiotensin converting enzyme (S-ACE), assumed to be a biochemical equivalent to Vc. We found that, after chemotherapy, patients showed a significant decline in several pulmonary function parameters, namely VC, TLC, and FEV1 (P < 0.0001, P = 0.0351, P = 0.0004, respectively), when compared to pre-treatment values. DCO was significantly impaired after chemotherapy (P < 0.0001), but with regard to its components, Vc values showed a significant decline (P = 0.0002), whereas Dm values were unchanged. Values of sP-III-P raised significantly after chemotherapy (P = 0.003), whereas S-ACE activity did not show any significant variation. When we looked at relationships between functional and biochemical parameter variations, the only significant correlation we found was between DCO and S-ACE (r2 = 0.112; P < 0.02). We conclude that in asymptomatic patients treated by bleomycin-including combination chemotherapy, DCO impairment is likely to occur because of a subclinical injury to pulmonary vessels, as suggested by Vc decline. Although the occurrence of pulmonary interstitial fibrosis after chemotherapy was excluded by chest X-ray examination and by stable values of Dm, sP-III-P elevation would suggest an accelerated type III collagen turnover in interstitial fibroblasts activated by bleomycin.
The production of oxygen-free radicals has been proposed as a determinant of the delayed toxicity of doxorubicin. The aim of the present investigation was to evaluate the potential cardioprotective effect of superoxide dismutase (SOD) and catalase (CAT) against the delayed cardiomyopathy induced by doxorubicin (DXR) in a rat model. Female Sprague Dawley rats received 3 mg/kg of DXR intravenously weekly for 4 weeks. SOD or CAT were administered intravenously at the dose of 10000 U/kg 2 min before and 30 min after each DXR administration. Cardiac toxicity was monitored by means of electrocardiography (QaT interval) and by light and electron microscopy evaluation of left ventricle fragments. DXR treated rats showed, in comparison with control animals, a decrease of body weight gain, a progressive and irreversible prolongation of QaT and significant morphologic lesions consisting in myocyte vacuolization and myofibrillar loss. SOD significantly prevented the impairment of body weight gain and QaT prolongation. Moreover, morphologic lesions were significantly reduced in rats receiving DXR + SOD. On the contrary, CAT seems to be completely devoid of protective effect.
4'-iodo-4'-deoxydoxorubicin was administered intravenously to 35 patients with advanced malignant neoplasms. The doses were escalated as follows: 2, 4, 6, 7, 10, 14, 19, 26, 52, 70, 80 and 90 mg/m2. Myocardial function was assessed by Holter monitoring and echocardiography. The prevalence of arrhythmias that could be attributed to the drug in the 24 h following infusion was 14.3% (supraventricular) and 10.6% (ventricular). Echocardiographic heart function variables were unchanged at 24 h and 21 days from drug injection. The data indicate the absence of significant, acute cardiotoxic effects of 4'-iodo-4'-deoxydoxorubicin.
The production of oxygen free radicals during anthracycline therapy has been proposed as a determinant of the toxicity of anthracyclines. Oxygen radical generation might specifically affect the myocardium because of the low antioxidant defense systems in cardiac tissue. The aim of the present investigations was to evaluate the potential cardioprotective effect of superoxide dismutase (SOD) against the delayed cardiomyopathy induced by doxorubicin (DXR) in a rat model. Female Sprague Dawley rats received 3 mg/kg of DXR intravenously weekly for 4 weeks. SOD was administered intravenously at the dose of 10,000 U/Kg one minute before and 30 minutes after each DXR administration. Cardiac toxicity was monitored in vivo by means of electrocardiography (QaT interval), by determining the contractile properties of isolated atria, and by light and electron microscopy evaluation of left ventricle fragments excised 5 weeks after the last DXR administration. The degree of morphologic lesions was quantitated according to the score system proposed by E. Billingham. DXR treated rats showed, in comparison with control animals treated with saline a decrease of body weight gain, a progressive and irreversible prolongation of QaT, decrease of contractility of isolated atria, and significant morphologic lesions consisting in myocyte vacuolization and myofibrillar loss. SOD significantly prevented the impairment of body weight gain, QaT prolongation and the impairment of myocardial contractility. Moreover morphologic lesions were significantly reduced in rats receiving DXR + SOD. The present data indicate that SOD could represent an important issue in myocardial protection against DXR cardiotoxicity.
The aim of the present investigation was to evaluate the potential cardioprotective effect of reduced glutathione (GSH) against the delayed cardiomyopathy induced by doxorubicin (DXR) in a well-documented rat model. DXR was administered i.v. at a weekly dose of 3 mg/kg for a total of 4 doses; 250 or 500 mg/kg of GSH was given i.v. 10 min before and 2 h after each DXR injection, resulting in a total weekly dose of 500 or 1000 mg/kg, respectively. The development of cardiotoxicity was monitored in vivo by means of electrocardiography (QaT duration), and was evaluated by measuring the contractile performance of isolated atria and by light and electron microscopy of left ventricular samples excised 5 weeks after the last DXR administration. DXR was found to impair body weight gain and to produce an irreversible and time-dependent prolongation of QaT, a decrease in myocardial contractility of isolated atria and typical morphologic alterations, including myocyte vacuolization and myofibrillar loss. Pretreatment with GSH at a dose of 500 mg/kg x 2, but not at 250 mg/kg x 2, partially prevented the impairment of body weight gain, QaT prolongation in ECG and the decrease in myocardial contractility of isolated atria induced by DXR. Alterations of the morphologic pattern were also significantly reduced in animals receiving the higher dose of GSH. Determinations of the cardiac non-protein sulfhydryl group content showed that GSH, at doses higher than or equal to 500 mg/kg, significantly increased this parameter, irrespective of the presence of DXR. In conclusion, the present data indirectly support the hypothesis that oxidative damage is involved in DXR cardiotoxicity and indicate that maintenance of the reduced thiol pool could be an important issue in myocardial protection.
The calcium antagonist flunarizine (FLN) was tested for its ability to prevent doxorubicin (DXR)-induced cardiotoxicity in the rat. A cumulative dose of 9.0 mg/kg of DXR was administered i.v. over a period of 1 week. FLN (10 mg/kg/day i.p., 6 days/week) was administered according to two different time schedules, covering respectively the first and last 4 weeks after the beginning of DXR treatment. The two schedules were adopted to assess whether early and/or delayed DXR-induced cardiotoxic effects were affected by FLN. The development of cardiac toxicity was monitored by ECG recordings. The animals were sacrificed 8 weeks after the beginning of DXR treatment. The contractile performance of isolated atria and the morphological pattern of left ventricular fragments were subsequently evaluated. The early administration schedule of FLN was shown to be ineffective in preventing DXR-induced cardiotoxicity and in some cases was actually found to potentiate the effects of DXR. In contrast, the histological evaluation of ventricular preparations from rats treated with DXR and FLN according to the delayed time schedule showed a significant improvement with respect to hearts from animals treated with DXR alone. An inhibition of the delayed calcium overload occurring after DXR administration has been proposed as a possible mechanism for this protective action.
Doxorubicin (DXR), administered iv in rats at the weekly dose of 3 mg/kg for 5 weeks, significantly impaired body weight gain and induced irreversible ECG alterations, mainly consisting of a progressive prolongation of ST and QT intervals. Five weeks after the last DXR administration, the contractile performance of atria isolated from treated animals was significantly reduced. At the same time, relevant morphologic lesions, consisting of myocyte vacuolization and myofibrillar loss, were also present in the myocardium of the same rats. The study showed that ICRF-187, administered ip at a dose of 125 mg/kg, significantly prevented body weight loss, QT and ST prolongation, and the decreased contractile force induced by DXR. In addition, ICRF-187 caused a significant reduction in incidence and severity of myocardial lesions. The cardioprotective effect of ICRF-187 is not mediated by a modification in DXR pharmacokinetics in heart, since the drug was actually found to increase DXR uptake in myocardial cells.
The effects of two sulfhydryl compounds, glutathione (GSH) and N-acetylcysteine (NAC), on the cardiotoxicity of doxorubicin (DXR) were tested on in vitro and in vivo models. DXR was administered to rats as 4 weekly i.v. doses of 3 mg/kg. GSH (1.5 mmoles/kg), given i.v. 10 min before and 1 hr after DXR, was found to prevent the development of the delayed cardiotoxic effects of DXR, as assessed by electrocardiographic and mechanical parameters, as well as by histological examination of left ventricular preparations. In contrast, equimolar oral doses of NAC (1 hr before and 2 hrs after DXR) were found to be ineffective. Both GSH and NAC prevented the negative inotropic effect produced by DXR on isolated rat atria. A good correlation exists between the cardioprotective effects of the two agents and their ability to enhance the non-protein sulfhydryl group content of the myocardium. Differences observed in vivo between GSH and NAC might be accounted for by pharmacokinetic factors.
Cardiac and vascular toxicity of recombinant interleukin-2 (rIL-2) was evaluated by in vitro and in vivo experiments in rats. Using isolated spontaneously beating atria, no changes were detected in heart rate or myocardial contractility in response to rIL-2 treatment at concentrations ranging from 0.1-100 U/ml. Daily sc administration of rIL-2 for 7 consecutive days (at doses of 2.3 X 10(4) to 1.15 X 10(6) U/ml) produced a prolongation of the QaT interval and significant modifications in serum electrolyte concentrations. Ex vivo contractility of atria excised at the end of rIL-2 treatment showed no deterioration in myocardial contractility with increasing dosage. rIL-2, at concentrations of 0.1-1000 U/ml, did not induce any modification of perfusion pressure in isolated rat tail artery but produced a significant displacement to the left of the dose-response curves for norepinephrine compared to basal conditions. The relative potencies were not dose-dependent. Our results indicate that rIL-2 does not exert a direct cardiotoxic effect, and suggest an indirect action on vascular smooth muscle, i.e., an aspecific modulation of vascular response to mediators.