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1.
Respir Med Res ; 77: 100-105, 2020 Mar.
Article in English | MEDLINE | ID: mdl-32512522

ABSTRACT

BACKGROUND: Immune checkpoint inhibitors (ICI) are now widely used at different stages of non-small cell lung cancers (NSCLC). Some clinical studies suggest that chemotherapy and immunotherapy have synergic activities, raising the question of the best therapeutic sequence. We studied the effect of chemotherapy in advanced NSCLC when administered after immunotherapy by nivolumab. METHODS: We performed a bicentric, retrospective, case-control study in two French hospitals. Patients with NSCLC treated with chemotherapy after nivolumab between January 2015 and January 2016 were included. Each case was matched on age and number of previous lines to one lung cancer patient who had not received nivolumab. Each CT-scanner has been reviewed and the objective response to chemotherapy was assessed for each patient according to the RECIST 1.1 criteria. RESULTS: Thirty-one patients with advanced NSCL who had at least received one cycle of chemotherapy after progression under nivolumab in the inclusion period were matched to 31 controls. The median age for cases was 59 yo and the predominant tumoral histology was adenocarcinoma (77%). The progression free survival (PFS) was 2.95 months in the studied group vs 2.69 months (P=0.18) in the control group. At best response, disease control (DC=partial response and stable disease) was better in the case group than in the control group (58% vs 39%, P=0.127). Cases were about five times more likely to get objective response to best evaluation than controls (OR=5.043 [95% CI: 0.975-26.086]; P=0.054). The overall survival (OS) was 7.3 months in the case group and 3.3 months in the control group (P=0.074). Patients who have been treated with targeted therapy instead of chemotherapy and patients with squamous lung cancer had worst PFS and OS. CONCLUSION: In advanced NSCLC, the chemotherapy progression free survival does not seem higher when administered after nivolumab. However, when administered post-nivolumab, traditional chemotherapy has 5 times more chances to achieve objective response and seems to improve overall survival of cases. Pooled analysis with other similar studies might be interesting for a next step.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Carcinoma, Non-Small-Cell Lung/drug therapy , Lung Neoplasms/drug therapy , Nivolumab/therapeutic use , Aged , Carcinoma, Non-Small-Cell Lung/diagnosis , Case-Control Studies , Chemotherapy, Adjuvant , Cohort Studies , Combined Modality Therapy , Female , France/epidemiology , Humans , Immunotherapy , Lung Neoplasms/diagnosis , Male , Middle Aged , Retrospective Studies , Treatment Outcome
3.
Metabolomics ; 15(9): 117, 2019 08 22.
Article in English | MEDLINE | ID: mdl-31440849

ABSTRACT

INTRODUCTION: Chagas disease, the most important parasitic infection in Latin America, is caused by the intracellular protozoan Trypanosoma cruzi. To treat this disease, only two nitroheterocyclic compounds with toxic side effects exist and frequent treatment failures are reported. Hence there is an urgent need to develop new drugs. Recently, metabolomics has become an efficient and cost-effective strategy for dissecting drug mode of action, which has been applied to bacteria as well as parasites, such as different Trypanosome species and forms. OBJECTIVES: We assessed if the metabolomics approach can be applied to study drug action of the intracellular amastigote form of T. cruzi in a parasite-host cell system. METHODS: We applied a metabolic fingerprinting approach (DI-MS and NMR) to evaluate metabolic changes induced by six different (candidate) drugs in a parasite-host cell system. In a second part of our study, we analyzed the impact of two drugs on polar metabolites, lipid and proteins to evaluate if affected pathways can be identified. RESULTS: Metabolic signatures, obtained by the fingerprinting approach, resulted in three different clusters. Two can be explained by already known of mode actions, whereas the three experimental drugs formed a separate cluster. Significant changes induced by drug action were observed in all the three metabolic fractions (polar metabolites, lipids and proteins). We identified a general impact on the TCA cycle, but no specific pathways could be attributed to drug action, which might be caused by a high percentage of common metabolome between a eukaryotic host cell and a eukaryotic parasite. Additionally, ion suppression effects due to differences in abundance between host cells and parasites may have occurred. CONCLUSION: We validated the metabolic fingerprinting approach to a complex host-cell parasite system. This technique can potentially be applied in the early stage of drug discovery and could help to prioritize early leads or reconfirmed hits for further development.


Subject(s)
Host-Parasite Interactions , Metabolomics/methods , Myoblasts/parasitology , Proteomics/methods , Trypanocidal Agents/pharmacology , Trypanosoma cruzi/drug effects , Animals , Cell Line , Lipid Metabolism , Magnetic Resonance Spectroscopy/methods , Mass Spectrometry/methods , Metabolome , Myoblasts/metabolism , Proteome/chemistry , Rats , Trypanosoma cruzi/metabolism , Trypanosoma cruzi/pathogenicity
4.
Int J Parasitol Drugs Drug Resist ; 8(1): 81-86, 2018 04.
Article in English | MEDLINE | ID: mdl-29425734

ABSTRACT

OBJECTIVES: Three new chemical series (bicyclic nitroimidazoles, aminopyrazoles and oxaboroles) were selected by Drugs for Neglected Diseases initiative as potential new drug leads for leishmaniasis. Pharmacodynamics studies included both in vitro and in vivo efficacy, cross-resistance profiling against the current antileishmanial reference drugs and evaluation of their cidal activity potential. METHODS: Efficacy against the reference laboratory strains of Leishmania infantum (MHOM/MA(BE)/67/ITMAP263) and L. donovani (MHOM/ET/67/L82) was evaluated in vitro on intracellular amastigotes and in vivo in the early curative hamster model. Cidal activity was assessed over a period of 15 days in an in vitro 'time-to-kill' assay. Cross-resistance was assessed in vitro on a panel of L. infantum strains with different degrees of resistance to either antimony, miltefosine or paromomycin. RESULTS: All lead compounds showed potent and selective in vitro activity against the Leishmania strains tested and no cross-resistance could be demonstrated against any of the current antileishmanial drugs. Cidal activity was obtained in vitro for all series within 15 days of exposure with some differences noted between L. donovani and L. infantum. When evaluated in vivo, all lead compounds showed high efficacy and no adverse effects were observed. CONCLUSIONS: The new lead series were shown to have cidal pharmacodynamic activity. The absence of cross-resistance with any of the current antileishmanial drugs opens possibilities for combination treatment to reduce the likelihood of treatment failures and drug resistance.


Subject(s)
Antiprotozoal Agents/administration & dosage , Antiprotozoal Agents/pharmacology , Leishmania donovani/drug effects , Leishmania infantum/drug effects , Leishmaniasis/drug therapy , Animals , Antimony/pharmacokinetics , Antimony/pharmacology , Antiprotozoal Agents/pharmacokinetics , Boron Compounds/administration & dosage , Boron Compounds/pharmacokinetics , Boron Compounds/pharmacology , Cricetinae , Female , Inhibitory Concentration 50 , Leishmaniasis/parasitology , Mice , Nitroimidazoles/administration & dosage , Nitroimidazoles/pharmacokinetics , Nitroimidazoles/pharmacology , Parasitic Sensitivity Tests , Pyrazoles/administration & dosage , Pyrazoles/pharmacokinetics , Pyrazoles/pharmacology
5.
J Chir (Paris) ; 146(3): 250-5, 2009 Jun.
Article in French | MEDLINE | ID: mdl-19643410

ABSTRACT

Human factors (HF) study is mandatory to get air transport pilot licences. In aviation, crew resource management (CRM) and declaration of adverse events (feedback) result in improving of air safety. Air missions and surgical procedures have similarities. Bridging the gap is tempting, despite severe warnings against simplistic adaptation. Putting HF theory into surgical practice: how to? Educational principles derived from CRM improve professional attitudes of a team. We propose to translate concepts of CRM to clinical teams. CRM training applying in surgery could allow the work environment to be restructured to reduce human error. Feedback: in aviation, the Bureau of Flight Safety deals with investigations for air events. Pilots, air traffic controllers can anonymously declare nuisance, resulting in a feedback for the whole air force. Adverse events are analysed. Usually, multilevel problems are found, rather than the only responsibility of the last operator. Understanding the mechanisms of human failure finally improves safety. In surgery, CRM and feedback would probably be helpful. Anyway, it requires time; people have to change their mind. Nevertheless people such as fighter pilots, who were very unwilling at the beginning, now consider HF as a cornerstone for security. But it is difficult to estimate the extent of HF-related morbidity and mortality. We propose as a first step to consider CRM and feedback in surgical procedure. HF deals with the mechanisms of human errors and the ways to improve safety and probably improve the surgical team's efficacy.


Subject(s)
Aviation , Computer Simulation , General Surgery/education , Safety Management , Humans
6.
J Chir (Paris) ; 146(1): 40-7, 2009 Feb.
Article in French | MEDLINE | ID: mdl-19446692

ABSTRACT

BACKGROUND: Esophageal perforation due to foreign body (FB) ingestion is an unusual occurrence. This study aims to define diagnostic difficulties of esophageal perforation by FB. PATIENTS AND METHODS: A chart review of patients on our service with FB esophageal perforation was carried out. Diagnosis of perforation was made by CT scan and/or esophagoscopy. Surgery was indicated when a FB could not be removed endoscopically or on a case-by-case basis according to clinical/laboratory, radiologic, and/or endoscopic findings. RESULTS: Seven patients (age range: 27 to 80 years) were admitted for esophageal FB perforation. All patients presented with dysphagia. Two patients presented with signs of sepsis more than 24 hours after FB ingestion. Perforation was diagnosed at initial evaluation in five cases (three by endoscopy, two by CT) and after FB extraction in two cases. Six patients underwent surgery (suture repair: n=4; esophageal exclusion: n=1; mediastinal drainage: n=1). Five surgeries were performed at the initial diagnosis and one after failure of medical management. Mortality was zero; one patient developed esophageal fistula. CONCLUSION: Diagnosis of FB esophageal perforation is difficult and is delayed in up to a quarter of patients. The perforation can be due to the FB itself or may be incurred during endoscopic extraction. Both CT and endoscopy are necessary for diagnosis and treatment. Most patients require surgical intervention.


Subject(s)
Esophagus/injuries , Foreign Bodies/complications , Adult , Aged , Aged, 80 and over , Deglutition Disorders/etiology , Esophagoscopy , Esophagus/surgery , Female , Foreign Bodies/surgery , Humans , Male , Middle Aged , Retrospective Studies , Tomography, X-Ray Computed
7.
J Chir (Paris) ; 145(5): 459-65, 2008.
Article in French | MEDLINE | ID: mdl-19106867

ABSTRACT

INTRODUCTION: Recent suicide bombings pose the novel problem for Trauma Centers of the massive simultaneous arrival of many gravely wounded patients. METHODS: We report the experience of the French-German Military Trauma Group, a Level 2 Trauma Center, in Afghanistan during the wave of suicide bombings in February 2007. RESULTS: Fourteen casualties were received. A first triage was carried out by the U S Army Level I group prior to evacuation. A second surgical triage was carried out with systematic ultrasound exam. Four cases (ISS>25) were re-categorized and underwent emergency surgical procedures. CONCLUSION: Suicide bombing in crowded locations near an evacuation hospital may overwhelm the medical resources of the receiving center. It has been referred to as "The Main Gate Syndrome." We introduced the novel concept of a semi-evacuation hospital or receiving center where a second surgical triage was carried out. These exceptional circumstances require open-minded flexibility, a tailored approach, and close cooperation between surgeons and anesthetists to share experience, opinions, and ideas. In the setting of mass casualties, emergency ultrasound exam was shown to be a valuable and effective tool by virtue of its mobility, reproducibility, and immediate results.


Subject(s)
Blast Injuries/surgery , Bombs , Emergency Medical Services/organization & administration , Mass Casualty Incidents , Abdominal Injuries/surgery , Adult , Afghanistan , Blast Injuries/diagnosis , Extremities/injuries , Extremities/surgery , Humans , Male , Middle Aged , Reproducibility of Results , Rescue Work/organization & administration , Retrospective Studies , Syndrome , Thoracic Injuries/surgery , Trauma Severity Indices , Treatment Outcome , Wounds, Penetrating/surgery , Young Adult
8.
J Chir (Paris) ; 144(5): 449-51, 2007.
Article in French | MEDLINE | ID: mdl-18065906

ABSTRACT

The nonspecific colon ulcer is a not a well-known disorder. A case of ulcer of the colic hepatic flexure is described. It was a case of pseudotumor and the pathological examination confirmed the diagnosis. The precise diagnosis of colon ulcer is useful for conservative treatment with coloscopic surveillance and to prevent a hemorrhagic complication or peritonitis after perforation. Contrary to diverticulitis, this pathology is most dominant on the right colon and particularly on the cecum. This explains the frequency of pseudoappendicular syndromes.


Subject(s)
Colonic Diseases/diagnosis , Ulcer/diagnosis , Biopsy , Colonic Diseases/surgery , Colonoscopy , Female , Humans , Middle Aged , Ulcer/surgery
10.
Article in English | MEDLINE | ID: mdl-12566826

ABSTRACT

To gain information about efficacy and safety of sunscreens, we compared the skin penetration of ultraviolet (UV) filters from two vehicles, i.e. an oil-in-water (O/W) emulsion gel and petrolatum jelly both in vitro and in vivo, as well as the corresponding pharmacological effect, i.e. the sun protection factor (SPF) in vivo. The UV filters studied were benzophenone-3 (BPH), ethylhexyl methoxycinnamate (EHM), butyl methoxydibenzoyl methane, ethylhexyl salicylate and homosalate. The human skin penetration of these five chemicals from the two vehicles was determined both in vitro using Franz cells and in vivo using a standardized tape-stripping method. The SPF of the two sunscreens was determined in vivo following the COLIPA guidelines. In vitro none of the filters permeated through the skin after 6 h of product application and very little could be found in the skin. BPH and EHM were the only UV filters found in the dermis (both after 30 min and 6 h). An effect of the vehicle could be noticed only for BPH after 30 min in the dermis and 6 h in both dermis and epidermis. In vivo, no differences in the amount of individual UV filters (in % of the applied dose) in the 15 first strips of the stratum corneum (SC) were found following 30 min of application of the formulations; however, the amount of UV filters that were retained in the SC was significantly higher (around 3 times) with the O/W emulsion gel than with the petrolatum jelly. This difference between the two vehicles was also of consequence for the SPF in vivo measured 30 min after application of the products (SPF congruent with 18 with the O/W emulsion gel compared to SPF congruent with 10 with the petrolatum jelly). By choosing the right vehicle or optimizing it, not only sunscreen products can be significantly improved in terms of pharmacological efficacy but the potential toxicological risk associated with the skin penetration of UV filters may be significantly reduced.


Subject(s)
Chalcones , Skin/drug effects , Sunscreening Agents/pharmacology , Adult , Alkanes/administration & dosage , Alkanes/pharmacology , Benzoates/administration & dosage , Benzoates/pharmacology , Benzophenones/administration & dosage , Benzophenones/pharmacology , Chemistry, Pharmaceutical , Chromatography, High Pressure Liquid , Cinnamates/administration & dosage , Cinnamates/pharmacology , Emulsions , Female , Gels , Humans , In Vitro Techniques , Middle Aged , Petrolatum , Pharmaceutical Vehicles , Propiophenones , Salicylates/administration & dosage , Salicylates/pharmacology , Skin/radiation effects , Skin Neoplasms/prevention & control , Sunscreening Agents/administration & dosage , Time Factors , Ultraviolet Rays
11.
Photochem Photobiol ; 74(3): 401-6, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11594052

ABSTRACT

It is now well documented that chronic UVA exposure induces damage to human skin. Therefore, modern sunscreens should not only provide protection from both UVB and UVA radiation but also maintain this protection during the entire period of exposure to the sun. UVA filters, however, are rare and not sufficiently photostable. We investigated the effect of the introduction of a new UV filter, bis-ethylhexyloxyphenol methoxyphenyl triazine (Tinosorb S), in oil in water sunscreen formulations on the photostability of butyl methoxydibenzoylmethane (Avobenzone [AVB]) after irradiation with an optically filtered Xenon arc source (UV irradiance adjusted at 1 mean effective dose [MED]/min). With spectrophotometrical methods to assess the sun protection factor (SPF) and UVA ratio and chromatographical methods to determine the amount of UV filters recovered after irradiation we showed that Tinosorb S prevented the photodegradation of AVB in a concentration-dependent way, leading to a sustained SPF and UVA ratio even after irradiation with doses of up to 30 MED. Since AVB was shown to destabilize ethylhexyl methoxycinnamate (EHM) we tested the effect of Tinosorb S in sunscreens containing this UV filter combination. Here too Tinosorb S showed photoprotective properties toward both UV filters. Thus, Tinosorb S can be used successfully to improve the photostability and efficiency of sunscreens containing AVB and EHM.


Subject(s)
Benzoates/radiation effects , Chalcones , Cinnamates/radiation effects , Phenols/pharmacology , Sunscreening Agents/pharmacology , Triazines/pharmacology , Benzoates/chemistry , Chemistry, Pharmaceutical , Cinnamates/chemistry , Drug Stability , Humans , In Vitro Techniques , Photochemistry , Propiophenones , Skin/drug effects , Skin/radiation effects , Sunscreening Agents/chemistry , Sunscreening Agents/radiation effects , Ultraviolet Rays/adverse effects
12.
Skin Res Technol ; 7(1): 49-55, 2001 Feb.
Article in English | MEDLINE | ID: mdl-11301641

ABSTRACT

BACKGROUND/AIMS: Irritant reactions to surfactants, cleansing products, soaps and detergents are common in clinical and occupational dermatology. Mildness has become a major benefit claimed, and testing for mildness now ranks among the first concerns of the manufacturing industry. A wealth of publications deals with this problem, trying to improve the methodology, reduce the costs of testing and facilitate decision-making. Differences in vivo can be measured clinically and/or instrumentally. This is difficult, as commercially available products are generally safe to use and none are harsh in the absolute sense. METHODS: Nineteen different products (syndets, shampoos, personal cleansers), all claiming to be mild, were tested in vitro by a newly introduced method, corneosurfametry. For evaluating the aggressiveness of the products, the calculation of an index of irritation (IOI) was proposed. A concentration-effect curve of sodium lauryl sulfate (SLS) as standard and model surfactant was obtained. Some of the products were further tested in vivo with a flex wash test and with a soap chamber test and compared to SLS. Bioengineering methods (transepidermal water loss TEWL, skin color) were used to evaluate the results. RESULTS AND CONCLUSIONS: The results of the corneosurfametry allowed us to classify the products in three categories, with increasing aggressiveness towards the stratum corneum, according to their IOIs. The in vivo tests were not able to discriminate between the products, but ranks from the results of the bioengineering measurements showed a good correlation between TEWL changes, but not between colour changes, and IOIs from corneosurfametry. Corneosurfametry emerged as a simple, low-cost and fast method for ranking commercial products according to their mildness. However, the skin bioengineering techniques showed that some products could lead to skin reactions, such as erythema, that could not be detected by the in vitro technique.


Subject(s)
Dermatitis, Allergic Contact/etiology , Irritants/adverse effects , Skin Tests/standards , Surface-Active Agents/adverse effects , Colorimetry , Humans , Patch Tests , Predictive Value of Tests , Water Loss, Insensible
13.
Rev Pneumol Clin ; 56(3): 205-8, 2000 Jun.
Article in French | MEDLINE | ID: mdl-10880947

ABSTRACT

Hydatidosis is a ubiquitous parasitic condition observed in a pulmonary localization in 30 to 40% of cases. The hydatid cyst develops slowly and is well tolerated by the host who presents no signs for a long period. Complications include compression, fissuration, rupture, anaphylactic shock or infection after a latency phase of variable duration. Treatment of pulmonary hydatidosis is classically surgical with enucleation of the cyst by cleavage between the adventice and the anhistic membrane via thorachotomy using the Ugon and Barret procedure. Needle aspiration is also possible via thorachotomy or thoracoscopy. Finally resection of the pulmonary parenchyma can be used to excise the hydatic cyst. We describe a thoracoscopic treatment using specific material, in a man with complications due to a voluminous pulmonary hydatid cyst.


Subject(s)
Echinococcosis, Hepatic/surgery , Thoracoscopy , Adult , Echinococcosis, Hepatic/diagnostic imaging , Humans , Male , Punctures , Suction , Therapeutic Irrigation , Tomography, X-Ray Computed
14.
Nat Cell Biol ; 1(4): 207-14, 1999 Aug.
Article in English | MEDLINE | ID: mdl-10559918

ABSTRACT

The F-box protein p45SKP2 is the substrate-targeting subunit of the ubiquitin-protein ligase SCFSKP2 and is frequently overexpressed in transformed cells. Here we report that expression of p45SKP2 in untransformed fibroblasts activates DNA synthesis in cells that would otherwise growth-arrest. Expression of p45SKP2 in quiescent fibroblasts promotes p27Kip1 degradation, allows the generation of cyclin-A-dependent kinase activity and induces S phase. Coexpression of a degradation-resistant p27Kip1 mutant suppresses p45SKP2-induced cyclin-A-kinase activation and S-phase entry. We propose that p45SKP2 is important in the progression from quiescence to S phase and that the ability of p45SKP2 to promote p27Kip1 degradation is a key aspect of its S-phase-inducing function. In transformed cells, p45SKP2 may contribute to deregulated initiation of DNA replication by interfering with p27Kip1 function.


Subject(s)
Cell Cycle Proteins/metabolism , Microtubule-Associated Proteins/metabolism , S Phase/physiology , Tumor Suppressor Proteins , Animals , Apoptosis/physiology , Binding Sites , Cell Cycle/physiology , Cell Cycle Proteins/chemistry , Cell Cycle Proteins/genetics , Cell Line , Culture Media, Serum-Free , Cyclin-Dependent Kinase Inhibitor p27 , Cyclin-Dependent Kinases/metabolism , DNA Replication , Gene Expression , Humans , Interphase/physiology , Mutation , Rats , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , S-Phase Kinase-Associated Proteins
16.
J Biol Chem ; 270(41): 24197-203, 1995 Oct 13.
Article in English | MEDLINE | ID: mdl-7592624

ABSTRACT

fgf3 has been implicated in the embryonic and fetal development of the mouse and as an oncogene in murine breast cancer. We describe a procedure to purify the product of the mouse fgf3 gene and show it to be a potent mitogen for some epithelial cell lines. Using a receptor binding competition assay, Fgf3 was shown to bind with high affinity to the IIIb isoforms of Fgf receptor (FgfR) 1 and FgfR2 (ID50 = approximately 0.8 nM) and with a lower affinity to the IIIc variant of FgfR2 (ID50 = approximately 9 nM). No competition for the binding of 125I-Fgf1 was observed for FgfR1 (IIIc), FgfR3 (IIIb and IIIc), or FgfR4. Mitogenicity assays using BaF3 cells containing individual Fgf receptors showed a pattern of response in agreement with the receptor binding results. A comparison of two mammary epithelial cell lines showed a marked difference of potency and dependence upon heparin in their response to mouse Fgf3, suggesting a complex interaction between the ligand and its low and high affinity receptors.


Subject(s)
Fibroblast Growth Factors/metabolism , Fibroblast Growth Factors/pharmacology , Heparin/pharmacology , Mitogens/metabolism , Protein-Tyrosine Kinases , Proto-Oncogene Proteins/metabolism , Proto-Oncogene Proteins/pharmacology , Receptors, Fibroblast Growth Factor/metabolism , 3T3 Cells , Animals , Base Sequence , Binding, Competitive , Cell Division/drug effects , Cell Line , Chlorocebus aethiops , DNA Primers , Embryonic and Fetal Development , Epithelium , Fibroblast Growth Factor 3 , Fibroblast Growth Factors/genetics , Kinetics , Mice , Mitogens/pharmacology , Molecular Sequence Data , Oncogenes , Polymerase Chain Reaction , Proto-Oncogene Proteins/genetics , Receptor, Fibroblast Growth Factor, Type 3
17.
Biochim Biophys Acta ; 1224(3): 418-26, 1994 Dec 30.
Article in English | MEDLINE | ID: mdl-7803499

ABSTRACT

The inhibition by d-alpha-tocopherol of protein kinase C activity has been studied in synchronised A7r5 rat smooth muscle cells during the cell cycle. Cell protein kinase C activity has been found to oscillate, with a minimum in the G0 phase, a maximum in the late G1 phase and a new minimum in the S phase. An inhibition of protein kinase C activity by d-alpha-tocopherol appears to be at the basis of cell growth inhibition. Nevertheless, the amount of the different protein kinase C isoenzymes present in smooth muscle cells, measured by their specific antibodies, does not change during the cell cycle in both untreated and d-alpha-tocopherol-treated cells. The possible mechanisms of protein kinase C modulation during the cell cycle and of its inhibition by d-alpha-tocopherol are discussed.


Subject(s)
Muscle, Smooth, Vascular/drug effects , Protein Kinase C/antagonists & inhibitors , Vitamin E/pharmacology , Animals , Cell Cycle , Cell Division/drug effects , Cells, Cultured , DNA/biosynthesis , Muscle, Smooth, Vascular/cytology , Muscle, Smooth, Vascular/enzymology , Rats
18.
Biochim Biophys Acta ; 1176(1-2): 83-9, 1993 Mar 10.
Article in English | MEDLINE | ID: mdl-7680904

ABSTRACT

alpha-Tocopherol, the most active form of vitamin E, causes a dose-dependent inhibition of serum-induced proliferation of smooth muscle cells (A7r5) in culture. Some tocopherol-related compounds exhibiting various degrees of antioxidant potency have also been tested on cellular proliferation. No direct correlation between the antioxidant activity of these compounds and their effect on smooth muscle cell growth could be observed. While most of the derivatives employed were not effective in inhibiting protein kinase C, in the case of alpha-tocopherol the antiproliferative effect was found to be parallel to the inhibition of protein kinase C activity, as measured in streptolysin-O permeabilized cells.


Subject(s)
Muscle, Smooth/drug effects , Naphthalenes , Protein Kinase C/metabolism , Vitamin E/analogs & derivatives , Vitamin E/pharmacology , Alkaloids/pharmacology , Cell Division/drug effects , Clone Cells/drug effects , Muscle, Smooth/cytology , Muscle, Smooth/metabolism , Polycyclic Compounds/pharmacology , Protein Kinase C/antagonists & inhibitors , Staurosporine , Thymidine/metabolism
19.
Mol Aspects Med ; 14(3): 265-71, 1993.
Article in English | MEDLINE | ID: mdl-8264342

ABSTRACT

Uncontrolled cell growth is at the basis of neoplastic proliferation and arteriosclerotic lesions. In vitro proliferation of vascular smooth muscle cells, Balb c/3T3 fibroblasts, retinal neuroepithelial cells and neuroblastoma cells is inhibited by d-alpha-tocopherol. On the contrary Chinese hamster ovary cells, osteosarcoma cells and macrophages are not sensitive. PDGF-BB activated proliferation is highly d-alpha-tocopherol sensitive while lysophosphatidic acid induced growth is poorly inhibited. d-beta-Tocopherol, an analogue of d-alpha-tocopherol, with similar antioxidant properties, does not inhibit proliferation. Protein kinase C activity is inhibited by d-alpha-tocopherol but not by d-beta-tocopherol, suggesting a central role of this enzyme in the control of cell proliferation by d-alpha-tocopherol. Activation of the transcription activation complex AP-1 (but not NFKB) is prevented by d-alpha-tocopherol and not by d-beta-tocopherol.


Subject(s)
Cell Division/drug effects , Vitamin E/pharmacology , 3T3 Cells , Animals , CHO Cells , Cell Line , Cricetinae , Humans , Mice , Mitogens/pharmacology , Muscle, Smooth/enzymology , NF-kappa B/metabolism , Protein Kinase C/metabolism , Proto-Oncogene Proteins c-jun/metabolism , Transcription, Genetic/drug effects , Tumor Cells, Cultured , Vitamin E/analogs & derivatives
20.
EXS ; 62: 164-77, 1992.
Article in English | MEDLINE | ID: mdl-1450584

ABSTRACT

The molecular events responsible for the inhibition of cell proliferation by alpha-tocopherol have been investigated. Smooth muscle cells in vitro have been shown to be specifically inhibited by alpha-tocopherol with a concomitant inhibition of protein kinase C activity. beta-Tocopherol was inactive, despite its similar radical scavenging activity. The point of inhibition of alpha-tocopherol relative to the cell cycle was localized in the late G1 phase. A second effect of alpha-tocopherol observed with smooth muscle cells was the stimulation of protein kinase C biosynthesis in both the S and G2 phases of the cell cycle. The implications of these findings for the onset of arteriosclerosis are discussed.


Subject(s)
Cell Division/drug effects , Muscle, Smooth, Vascular/drug effects , Vitamin E/pharmacology , 3T3 Cells , Animals , Aorta/cytology , Aorta/drug effects , Bombesin/pharmacology , Cell Cycle/drug effects , Cell Line , Endothelins/pharmacology , Fibroblasts/cytology , Fibroblasts/drug effects , G1 Phase/drug effects , Kinetics , Mice , Muscle, Smooth, Vascular/cytology , Osteosarcoma , Phorbol 12,13-Dibutyrate/metabolism , Platelet-Derived Growth Factor/pharmacology , Protein Kinase C/antagonists & inhibitors , Rats , Vitamin E/analogs & derivatives
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