In vitro acute effects of tobacco smoke on tumor necrosis factor alpha and interleukin-6 production by alveolar macrophages.

Tobacco smoke is a usual form of oxidant aggression present in the domestic environment. In the present study, the in vitro acute effects of a 2-cigarette smoke gas phase were evaluated on cell viability and cytokine secretion by alveolar macrophages (AM) from guinea pigs and human healthy subjects. Cell injury was estimated immediately after smoke exposure by evaluation of ATP cell content (measured by bioluminescence) and lactic dehydrogenase (LDH) release in the culture medium. LDH release was also measured when the interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF) activities were evaluated. No cytotoxic effect was found: The ATP cell content of both guinea pig AM and human AM did not significantly change after tobacco smoke exposure. Similarly, the LDH release in the culture medium was unchanged both immediately after tobacco smoke exposure and at the time of the cytokine evaluation (18-20 h later) compared to cells cultured in the air. The total protein synthesis by the guinea pig AM evaluated by 35S-L-methionine labeling was unaffected by tobacco smoke exposure. The production of IL-6 and TNF activities was evaluated 18-20 h after smoke exposure. The IL-6 activity was measured by the proliferation test of 7TD1 hybridoma cell line; the TNF activity was evaluated by the L929 mouse fibroblast cytotoxic test and by an immunoradiometric assay (for human AM). A 2-cigarette smoke exposure decreased both activities significantly. The exposure of the guinea pig AM reduced IL-6 activity by 24.3 +/- 6.7%, 42.4 +/- 7.8%, and 39.7 +/- 9.6% and TNF activity by 33.8 +/- 10.4%, 35.1 +/- 10.7%, and 38.8 +/- 9.9% (respectively unstimulated cells and AM activated by 0.1 and 10 micrograms LPS/mL). The decrease in monokine production by the human AM was, respectively, 57.8 +/- 8.8%, 59.7 +/- 11.4%, and 49.9 +/- 10.5% of IL-6 activity and 37.4 +/- 14.6%, 17.6 +/- 9.6%, and 37.2 +/- 6.3% of TNF activity. The possible release of cytokine inhibitors was also investigated. The inhibitory activity against recombinant TNF and IL-6 was evaluated in culture medium from unstimulated AM exposed to tobacco smoke and did not significantly differ from that of AM exposed to air, demonstrating that the decrease of monokine levels could not be explained by the release of inhibitory factors.(ABSTRACT TRUNCATED AT 400 WORDS)

[In vivo kinetics of cotrimoxazole in alveolar macrophages]. / Cinétique in vivo du cotrimoxazole dans les macrophages alvéolaires.

The aim of this work was to study the kinetic of intramacrophage penetration of cotrimoxazole in guinea pigs which had received 100 mg/kg of sulfamethoxazole and 20 mg/kg of trimethoprim after a single intraperitoneal injection. 30 minutes, 1, 3, 6 and 24 hours after this injection an intra-cardiac blood sample was taken and pulmonary lavage was performed immediately after sacrificing the animal by cervical cord dislocation. The level of trimethoprim and sulfamethoxazole was measured in each sample by high performance liquid chromatography (HPLC). An estimation of the dilution of the supernatant was obtained by comparing the supernatant glucose with the serum glucose. The serum kinetics of trimethoprim and sulfamethoxazole progressed in a parallel fasion with time with a maximal concentration at 30 minutes (for trimethoprim: 6.7 +/- 0.9 micrograms/ml and for sulfamethoxazole 176.1 +/- 16.2 micrograms/ml). On the other hand their penetration capacity was different in the supernatant and in the alveolar macrophages: the maximal concentrations were obtained after one hour in the supernatant and after 3 hours in the cellular extract and were respectively for trimethoprim 0.43 +/- 0.07 microgram/ml and 20.9 +/- 8.06 micrograms/ml of intramacrophage water and for sulfamethoxazole 1.86 +/- 0.24 micrograms/ml and 23.8 +/- 12.7 micrograms/ml of intramacrophage water. A concentration around six times greater was noted for the trimethoprim inside the cells compared with serum and was only 0.25 time for sulfamethoxazole. On the other hand the supernatant/serum ratio showed a greater concentration for trimethoprim (4 to 10) than for sulfamethoxazole (0.6 to 1).(ABSTRACT TRUNCATED AT 250 WORDS)

The penetration of co-trimoxazole into alveolar macrophages and its effect on inflammatory and immunoregulatory functions.

The pharmacokinetics of co-trimoxazole in serum, bronchoalveolar lavage-fluid (BAL-fluid) and alveolar macrophages (AM) of guinea pigs receiving sulphamethoxazole (100 mg/kg) and trimethoprim (20 mg/kg) were studied. HPLC showed that peak co-trimoxazole levels were obtained in serum at 30 min, in BAL-fluid at 1 h and in AM at 3 h. A comparison between mean concentrations in serum, BAL-fluid and AM showed a six-fold higher concentration of trimethoprim in cells than in serum, but only 0.25-fold of sulphamethoxazole. The BAL-fluid/serum ratio was four to ten times higher for trimethoprim than for sulphamethoxazole (0.6-to-one-fold). Sulphamethoxazole/trimethoprim ratios (30 min, 1 and 3 h) were lower in BAL-fluid (4.9 +/- 0.5) and in AM (1.4 +/- 0.5) than in serum (30.7 +/- 1.6). The influence of co-trimoxazole in vitro on microbicidal capacities (superoxide anion and hydrogen peroxide generations), immunoregulation (production of interleukin 1) and pro-inflammatory agent production (tumour necrosis factor) of guinea pigs' AM was also studied. No significant effect of co-trimoxazole on superoxide anion and hydrogen peroxide generations, or on interleukin 1 and TNF production, was demonstrable.

[Study of the in vivo penetration of cotrimoxazole in alveolar macrophages]. / Etude de la pénétration in vivo du cotrimoxazole dans les macrophages alvéolaires.

Kinetic of cotrimoxazole was studied in serum, alveolar macrophages and BAL fluid from guinea pigs receiving sulfamethoxazole (SMX, 100 mg/kg) and trimethoprim (TMP, 20 mg/kg). Guinea pigs were killed by cervical dislocation 30 min, 1 h, 3 h, 6 h and 24 h after intraperitoneal injection. Lung lavage was performed to obtain alveolar macrophages and BAL fluid. TMP and SMX levels were assayed using high-performance-liquid chromatography. Highest SMX levels were obtained in serum at 30 min, in BAL fluid at 1 h and in alveolar macrophages at 3 h. Mean SMX/TMP ratios (30 min, 1 h, 3 h) was 26.5 +/- 0.8 in serum, 3.76 +/- 1.8 in BAL fluid and 1.15 +/- 0.02 in alveolar macrophages.