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Biomedical subjects

M Bucci

Publications and source records attributed to M Bucci.

At least 19 recordsLinked to original sources

Dual inhibitors of cyclooxygenase and 5-lipoxygenase. A new avenue in anti-inflammatory therapy?

Nonsteroidal anti-inflammatory drugs (NSAIDs) are a mainstay in the treatment of inflammatory disease and are among the most widely used drugs worldwide. They are anti-inflammatory, antipyretic, and analgesic and are prescribed as first choice for the treatment of rheumatic disorders and, in general, inflammation. The main limitation in using NSAIDs consists in their side-effects, including gastrointestinal ulcerogenic activity and bronchospasm. The mechanism of action of these drugs is attributed to the inhibition of cyclooxygenase (COX), and, consequently, the conversion of arachidonic acid into prostaglandins. It is hypothesized that the undesirable side-effects of NSAIDs are due to the inhibition of COX-1 (constitutive isoform), whereas the beneficial effects are related to the inhibition of COX-2 (inducible isoform). Arachidonic acid can also be converted to leukotrienes (LTs) by the action of 5-lipoxygenase (5-LOX). LTC(4,) LTD(4,) and LTE(4) are potent bronchoconstrictors, whereas LTB(4) is chemotactic for leukocytes and plays an important role in the development of gastrointestinal ulcers by contributing to the inflammatory process. Thus, developing dual inhibitor compounds that will simultaneously inhibit COX and 5-LOX could enhance their individual anti-inflammatory effects and reduce the undesirable side-effects associated with NSAIDs, especially of the gastrointestinal tract. The most promising COX/5-LOX inhibitor is ML3000 ([2,2-dimethyl-6-(4-chlorophenyl)-7-phenyl-2,3-dihydro-1H-pyrrolizine-5-yl]-acetic acid), now in Phase III clinical trials. This new approach will certainly help to unravel the mechanisms at the root of the undesirable effects of NSAIDs and to develop safer NSAIDs.

Anti-Inflammatory Agents, Non-Steroidal↗

Halipeptins A and B: two novel potent anti-inflammatory cyclic depsipeptides from the Vanuatu marine sponge Haliclona species.

Two new metabolites, named halipeptins A and B, have been isolated from the marine sponge Haliclona sp. Their structures were determined by extensive use of one- and two-dimensional NMR experiments, mass spectrometry, and UV and IR spectroscopy. Halipeptin A is a novel 17-membered cyclic depsipeptide, consisting of five residues including two alanines (with L stereochemistry) and three new residues that appear to be previously undescribed from natural sources: 1,2-oxazetidine-4-methyl-4-carboxylic acid, 3-hydroxy-2,2,4-trimethyl-7-methoxydecanoic acid (HTMMD), and N-methyl-delta-hydroxyisoleucine. The HTMMD residue is substituted with 3-hydroxy-2,2,4-trimethyl-7-hydroxydecanoic acid in halipeptin B. Halipeptin A was found to possess very potent anti-inflammatory activity in vivo, causing about 60% inhibition of edema in mice at the dose of 300 microg/kg (i.p.).

Animals↗

Hormonal control of enzyme activity during the plasma membrane transformation of uterine epithelial cells.

Ultrastructural and light microscopic catalytic histochemical methods were used to study the distribution and changes in distribution of four phosphatase enzymes; alkaline phosphatase, 5'-nucleotidase, thiamine pyrophosphatase and adenosine triphosphatase in uterine epithelial cells in response to the ovarian hormones, oestrogen, progesterone or a combination of both used in different regimes on ovariectomised rats. Reaction product for all four enzymes was clearly localised in the epithelial cells, especially with oestrogen priming. However, the four enzymes showed markedly different patterns of organisation of reaction product in response to other hormonal treatments. Our findings clearly show that the expression of these enzymes is under ovarian hormonal control. However, while all of the enzymes are upregulated by oestrogen, the response to progesterone is variable, which can upregulate or downregulate different enzymes. The findings are particularly obvious at the electron microscopic level on the apical plasma membrane of the uterine epithelial cells, which was the main focus of our study.

5'-Nucleotidase↗

Carotid and femoral ultrasound morphology screening and cardiovascular events in low risk subjects: a 10-year follow-up study (the CAFES-CAVE study(1)).

BACKGROUND: Subclinical arteriosclerotic lesions at the carotid and femoral bifurcations may be related to the occurrence of future cardiovascular events and of occult arteriosclerotic coronary disease. B-mode ultrasound of carotid and femoral arteriosclerotic bifurcation lesions may provide a simple screening method to select asymptomatic subjects at risk of future events. METHODS AND RESULTS: 13221 low-risk, healthy, asymptomatic individuals were included in a 10-year, prospective, follow-up based on carotid and femoral bifurcation morphology defined by B-mode ultrasound. Four classes were considered at inclusion (I: normal wall, II: wall thickening, III: non-stenosing plaques, IV: stenosing plaques). When 10000 subjects (75.6% of included subjects; 6055 males, 3945 females) completed the 10-year follow-up the study was concluded. At 10 years there were 10 events (out of 7989 subjects) in class I and 81 events in II (930 subjects; incidence=8.6%); 239 events were observed in class III (611 subjects; 39.28%) and 381 events (470 subjects; 81.06%) in IV; 61 deaths occurred in classes III+IV (1081 subjects) producing a death rate within these two classes of 5.5% (51 out of 61=81.5% in class IV). The increased event rates in classes III and IV were significant (log rank; P<0.02) in comparison with I and II. CONCLUSIONS: Carotid and femoral morphology identified 2011 subjects (20.1% of the population) in classes II,III,IV including 98.6% of cardiovascular events and deaths in the following 10 years. A higher (P<0.05) rate of progression in classes III and IV in comparison with I and II was also observed. The ultrasound carotid and femoral classification was useful in selecting subjects at very low risk of cardiovascular events (class I), those at limited risk (class II) and a group at moderate risk (class III). A subpopulation at high risk of cardiovascular events (IV) was identified.

Adult↗

Oxygen-free radical decrease in hypertensive patients treated with lercanidipine.

BACKGROUND: The relationship between oxidative stress, lipoproteins, cardiovascular risk factors and vascular disease progression has recently attracted fresh attention due to the possibility of measuring free radicals (FRs). The aim of this study was to evaluate blood plasma variations in oxygen FRs in hypertensive patients treated with lercanidipine, a drug acting on blood pressure and microcirculation. METHODS: Twenty-two patients with moderate hypertension (M:F=12:10; age=52) and no vascular disease (evaluated by high-resolution ultrasound) were treated for 24 weeks with Lercanidipine (10 mg/day or 20 mg/day if BP values did not decrease at least 15 percent after four weeks of treatment). BP was measured at inclusion and after 4, 8, 12 and 24 weeks of treatment. FRs measurements (using the D-Roms test) were made at inclusion, at the 8th, 12th and 24th week. RESULTS: All patients completed the treatment which was well tolerated and without side effects. Systolic and diastolic BP decreased after 8, 12 (p<0.05) and 24 weeks (at 24 weeks systolic pressure was decreased by 21.1 percent, and diastolic by 11.1 percent; p<0.02). FRs levels progressively decreased from 541 Carr Units (SD 54) at inclusion to 411 (SD 56) at eight weeks (p<0.05), to 401 (SD 35) (p<0.05) at 12 weeks and finally to 398 (SD 33), (p<0.02) at 24 weeks of treatment (72.2 percent of the initial value). CONCLUSIONS: The possibility of measuring FRs in vivo with a simple, inexpensive test allows the identification of subjects with a high level of oxidative stress, and the monitoring of the effects of treatments. Lercanidipine, acting on blood pressure, on the microcirculation and decreasing oxidative stress and Frs plasma levels may effectively decrease the rate of progression of cardiovascular diseases offering the advantage of an increased level of protection in patients with high levels of oxidative stress.

Adult↗

Effects of the total triterpenic fraction of Centella asiatica in venous hypertensive microangiopathy: a prospective, placebo-controlled, randomized trial.

The aim of this study was to demonstrate whether total triterpenic fraction of Centella asiatica (TTFCA), was effective in improving the microcirculation in venous hypertension and microangiopathy. Forty patients with severe venous hypertension, ankle swelling, lipodermatosclerosis were included. After informed consent, patients were randomized into a treatment and a placebo group: those in the treatment group received TTFCA (tablets, 60 mg, twice daily for 8 weeks). The two groups of subjects were comparable for age and sex distribution. The mean age was 48 years (SD 9; M:F= 11:11) in the treatment group (22 patients) and 47.6 (SD 7; M:F= 10:8) in the placebo group (18 patients). There were no differences between placebo and treatment group at inclusion; there was no change between inclusion and measurements at 8 weeks in the placebo group. A decrease (p < 0.05) in RF (flux at rest) and RAS (rate of ankle swelling) were observed in the treatment group. The decrease in capillary filtration was associated with improvement in signs and symptoms (p < 0.05). The difference in flux, signs and symptoms, and filtration was clinically important at 8 weeks. No side effects were observed. In conclusion venous microangiopathy was improved by TTFCA treatment.

Administration, Oral↗

Increase in echogenicity of echolucent carotid plaques after treatment with total triterpenic fraction of Centella asiatica: a prospective, placebo-controlled, randomized trial.

The aim of this study was to evaluate whether total triterpenic fraction of Centella asiatica (TTFCA), was effective in modulating collagen production over 12 months, by producing an increase in echogenicity in echolucent carotid plaques. Part I was a pilot study aimed at evaluating the effects of TTFCA on different types of plaques. Part II was a prospective, randomized, placebo-controlled trial aimed at evaluating the effects of TTFCA on hypoechoic-echolucent plaques. The sonographic examination of carotid plaques was made with high-resolution ultrasound. Capturing, digital image processing, and normalization were standardized, interobserver, intrascanner, gain-level variability were standardized using as reference blood (black) for the most echolucent parts of the plaque and the adventitia (white) as the most echogenic part. Normalization of echo texture was obtained and plaque characterization differentiated echo-texture of plaque associated with events and those that did not cause embolization, thrombosis, or cardiovascular events. After identifying plaques at higher risk, patients were treated with TTFCA (oral tablets, 60 mg, thrice daily for 12 months) to evaluate whether this compound, by modulating collagen synthesis, could increase the echogenicity and therefore the stability of echolucent plaques. Part II was aimed at evaluating the effects of TTFCA on hypoechoic-echolucent plaques. Asymptomatic patients with echolucent plaques (GSM<18) were treated with TTFCA (60 mg, oral tablets three times daily for 12 months) or with comparable placebo after informed consent. All patients were also treated with antiplatelet agents. In part 1, at inclusion the GSC in the hypoechoic group was 15 (range, 12-18) while in the hyperechoic group it was 26 (range, 24-31); at 6 months it was increased in the hypoechoic group and at 12 months the increase was significant (19.5; p<0.05). There was a minor increase in GSM in the hyperechoic group (30; ns). In part II in the treatment group there was a significant difference in GSM (increase) at 12 months (p<0.05), improvement in texture (p<0.05) and a nonsignificant decrease in stenosis. No changes were observed in the placebo group. Events were observed in 6.5% of patients in the TTFCA group and in 11% in the control group (p<0.05). In conclusion these observations suggest a positive action of TTFCA on the stabilization of hypoechoic, low-density carotid plaques.

Administration, Oral↗

Treatment of diabetic microangiopathy and edema with total triterpenic fraction of Centella asiatica: a prospective, placebo-controlled randomized study.

The aim of this study was to demonstrate in a prospective, placebo-controlled, randomized study, whether total triterpenic fraction of Centella asiatica (TTFCA) is effective in improving the microcirculation in diabetic microangiopathy and neuropathy, Patients with severe diabetic microangiopathy, neuropathy, and edema; patients with microangiopathy without neuropathy; and healthy subjects were included. Microangiopathy was defined by laser Doppler and capillary filtration (rate on ankle swelling). Inclusion criteria were increase in resting flux and rate of ankle swelling; decrease in venoarteriolar response (VAR) and alteration in flux increase with temperature. Patients were randomized: the treatment group received TTFCA (tablets, 60 mg twice daily for 12 months); those in the placebo group received similar tablets. Healthy controls were followed up as a reference. Groups were comparable; there were no dropouts. There were no differences in the treatment and placebo groups at inclusion. Treatment was well tolerated; no side effects were reported. No variations were observed in normals at 12 months. In the neuropathy A-group, decreases (p<0.05) in RF and RAS were observed in the two treatment groups. The decrease in RAS was associated with a decrease in edema (p<0.05) in both treatment groups. The differences in flux (38%) and in VAR (38%) were associated with a decrease (28%) in the rate of ankle swelling (p<0.05). In patients without neuropathy (B-group) the decrease in flux was 22%, the VAR increased 22.7%, and the RAS decreased 9.5% at 12 months. The variations in normals and the progressive deterioration observed in untreated patients in both groups indicates the difference between treatment and placebo. In conclusion, the decrease in capillary filtration and edema is associated with symptomatic improvement. The action on edema is beneficial for the evolution of neuropathy. The effects of TTFCA on flux, RAS, and edema are important in early stages of microangiopathy to avoid progression to clinical stages.

Administration, Oral↗

Flight microangiopathy in medium- to long-distance flights: prevention of edema and microcirculation alterations with total triterpenic fraction of Centella asiatica.

The aim of this study was the evaluation of microcirculatory alterations associated with edema in passengers travelling for more than 3 hours and the study of the effects of TTFCA (total triterpenic fraction of Centella asiatica) on the development of microcirculation alterations and edema, in a prospective, randomized study. Laser Doppler flowmetry (LDF), transcutaneous PO2 and PCO2, rate of ankle swelling (RAS) were used. Subjects were randomized after informed consent into two groups: one control group (no drug or other treatment), and a treatment group (TTFCA 60 mg thrice daily for 2 days before the flight, the day of the flight, and for another day after the flight). Inclusion criteria were age range between 30 and 50, mild-moderate superficial venous disease with varicose veins. Subjects traveled in economy class. In controls there was a progressive increase in CO2, RAS, and edema score and a progressive decrease in flux (RF) and venoarteriolar response with flying time. The variations in all parameters were milder (p>0.05) in the TTFCA group. RAS and edema were significantly lower in the TTFCA-treated group (p<0.025). The progressive increase in RAS, PCO2, and the decrease in VAR and O2 were linearly associated with flight time (up to 10 hours). These results are very interesting and indicate an option for patients prone to edema and microcirculation disturbances during long flights.

Adult↗

Microcirculatory effects of total triterpenic fraction of Centella asiatica in chronic venous hypertension: measurement by laser Doppler, TcPO2-CO2, and leg volumetry.

The aim of this prospective, randomized study was to demonstrate whether an oral preparation of TTFCA was effective in improving the microcirculation and edema (leg volume) in venous microangiopathy. Forty patients with venous hypertension were included. Treatment was prescribed for 6 weeks (tablets, 60 mg twice daily). Patients were randomized into a treatment and a placebo group. There were 20 patients in each group. In the treatment group the mean age was 42 (SD 7; M:F = 10:10); in the placebo group, the mean age was 40 (SD 9; M:F = 10:10). Tolerability and compliance were very good; there were no dropouts. At inclusion there were no differences between placebo and treatment group. After treatment there was a decrease in resting flux (29%) and an improvement (increase) in venoarteriolar response (52%); PO2 was increased (7.2%) and PCO2 decreased (9.6%). There was an important decrease in leg volume (66 mL decrease; 1.3% volume variation). The difference in flux, O2-CO2 and volume parameters were significant and clinically important at 6 weeks in the treatment group. In conclusion, TTFCA improves microcirculation and leg volume in venous hypertension. The effects of TTFCA are observed even in a limited sample of patients.

Adult↗

Evaluation of treatment of diabetic microangiopathy with total triterpenic fraction of Centella asiatica: a clinical prospective randomized trial with a microcirculatory model.

Fifty patients with diabetic microangiopathy were studied by laser Doppler flowmetry (measuring skin blood flow at rest) (RF) and the venoarteriolar response (VAR), by transcutaneous PO2 and PCO2 measurements, and by capillary permeability evaluation (rate of ankle swelling [RAS]). Thirty of these patients were treated for 6 months with total triterpenic fraction of Centella asiatica (TTFCA) (60 mg twice daily), a drug active on microcirculation and capillary permeability. A control group of ten patients was treated with placebo and another group of ten patients was left without treatment thus acting as a second control group. After six months there were no significant changes in the two control groups. There was a significant improvement of microcirculatory parameter in patients treated with TTFCA. RF (abnormally increased at the beginning of the treatment) decreased, and the VAR (impaired at the beginning of the study) improved. PO2 increased and PCO2 decreased the abnormally increased capillary permeability was also improved (decreased). According to these data, TTFCA is useful in diabetic microangiopathy by improving microcirculation and decreasing capillary permeability. Also TTFCA protects against the deterioration of microcirculation due to diabetic microangiopathy.

Adult↗

Total triterpenic fraction of Centella asiatica in the treatment of venous hypertension: a clinical, prospective, randomized trial using a combined microcirculatory model.

A single-blind, placebo-controlled, randomized study was performed on the effects of different doses of the total triterpenic fraction of Centella asiatica (TTFCA) in patients with venous hypertensive microangiopathy. A combined microcirculatory model that considers laser Doppler flowmetry (LDF) and transcutaneous oxygen (PO2), transcutaneous carbon dioxide tension (PCO2) measurements was combined with the symptom evaluation. LDF tests included the baseline resting flow, the venoarteriolar reflex, and the variation of flow related to the temperature increase. All tests provided a significant difference between drug-treated groups and the placebo group, thereby allowing a distinction to be made between the higher (120 mg daily) and the lower (60 mg daily) dose of TTFCA. Transcutaneous PO2-PCO2 measurements were significantly modified by drug treatments, while no variation could be detected in the placebo group. Important symptomatologic effects (evaluated by subjective scores) followed TTFCA administration, especially at the higher dose level, while no effect was obtained with placebo. The trend of symptom evaluation paralleled the results of objective tests of our microcirculatory model, providing evidence that this model can reveal effects of venoactive drugs on venous hypertensive microangiopathy. TTFCA displays a significant activity. Doses as high as 120 mg daily may be safely used in venous hypertension.

Adult↗

Total triterpenic fraction of Centella asiatica in chronic venous insufficiency and in high-perfusion microangiopathy.

Total triterpenic fraction of Centella asiatica (TTFCA) is effective in improving venous wall alterations in chronic venous hypertension and in protecting the venous endothelium. TTFCA is active on connective tissue modulation, improves the synthesis of collagen and other tissue proteins by modulating the action of fibroblasts in the vein wall, and stimulates collagen remodeling in and around the venous wall. This is due to the modulating action of TTFCA on fibroblasts as shown by experiments on the growth of human embryonal fibroblasts. TTFCA has a moderate in-vitro and in-vivo stimulating effect on collagen synthesis and, at higher dosages, an inhibition on the synthesis of collagen and acid mucopolysaccharides. Studies have indicated the role of TTFCA on the synthesis of specific venous wall elements by cell cultures of human embryonal fibroblasts. The tissue-stimulating action is shown by the increased collagen production independent from the stimulation of cell proliferation (this differentiates the action of TTFCA from cell growth factors). TTFCA is active on the microcirculation in venous and diabetic microangiopathy. Signs and symptoms of venous hypertension and edema are improved by treatment. The remodeling on collagen synthesis could be one of the possible mechanisms of actions of TTFCA in the remodeling of echolucent (soft; therefore, with risk of thrombosis and embolization) plaques at the carotid and femoral bifurcation. This compound is safe and well tolerated. In conclusion, several actions of TTFCA in vascular diseases makes the use of this compound very interesting in venous and arterial problems.

Chronic Disease↗

Temporal events underlying arterial remodeling after chronic flow reduction in mice: correlation of structural changes with a deficit in basal nitric oxide synthesis.

To define the cellular events of vascular remodeling in mice, we measured blood flow and analyzed the morphology of remodeled vessels at defined points after a flow-reducing remodeling stimulus for 3, 7, 14, and 35 days. Acute ligation of the left external carotid artery reduced blood flow in the left common carotid artery (LC) compared with sham and contralateral right common carotid arteries (RCs). In morphometric analyses, the decrease in diameter in LCs was reversible by vasodilator perfusion 3 days after ligation, whereas ligation for 7 days or greater resulted in a permanent diameter reduction. Coincident with structural remodeling at day 7 was an increase in cell death in remodeled LCs. Functionally, rings from remodeled LCs contracted to prostaglandin F(2alpha) and relaxed to acetylcholine in a manner identical to that of control arteries. However, remodeled LCs were hypersensitive to the nitrovasodilator sodium nitroprusside (at day 7) and exhibited a marked reduction in basal NO synthesis at 7 and 14 days after ligation. The impairment of endothelial NO synthase function was likely due to post-translational mechanisms, given that endothelial NO synthase mRNA and protein levels did not change in remodeled LCs. These data define the ontogeny of flow-triggered luminal remodeling in adult mice and suggest that endothelial dysfunction occurs during reorganization of the vessel wall.

Animals↗

Inflammation-coagulation network: are serine protease receptors the knot?

Following an injury, the body recruits a mechanism to delimit and repair tissue damage; this phenomenon is known as inflammation. Among the several different pathways that are activated during this process, which is necessary for survival, activation of the coagulation pathway is a key feature. In fact, clinical changes in blood fluidity have been closely related to ongoing inflammation. Recent evidence suggests that serine protease receptors might play a major role in the host defence mechanism at the interface between coagulation and inflammation.

Animals↗

In vivo delivery of the caveolin-1 scaffolding domain inhibits nitric oxide synthesis and reduces inflammation.

Caveolin-1, the primary coat protein of caveolae, has been implicated as a regulator of signal transduction through binding of its "scaffolding domain" to key signaling molecules. However, the physiological importance of caveolin-1 in regulating signaling has been difficult to distinguish from its traditional functions in caveolae assembly, transcytosis, and cholesterol transport. To directly address the importance of the caveolin scaffolding domain in vivo, we generated a chimeric peptide with a cellular internalization sequence fused to the caveolin-1 scaffolding domain (amino acids 82-101). The chimeric peptide was efficiently taken up into blood vessels and endothelial cells, resulting in selective inhibition of acetylcholine (Ach)-induced vasodilation and nitric oxide (NO) production, respectively. More importantly, systemic administration of the peptide to mice suppressed acute inflammation and vascular leak to the same extent as a glucocorticoid or an endothelial nitric oxide synthase (eNOS) inhibitor. These data imply that the caveolin-1 scaffolding domain can selectively regulate signal transduction to eNOS in endothelial cells and that small-molecule mimicry of this domain may provide a new therapeutic approach.

Animals↗

Anti-very late antigen-1 monoclonal antibody modulates the development of secondary lesion and T-cell response in experimental arthritis.

Rats injected in the hind paw with a mixture of Mycobacterium butirricum emulsified in mineral oil (FA) developed a severe polyarthritis that shared some immunological features with human rheumatoid arthritis. After this local administration, rats developed a secondary lesion (edema) in the contralateral paw, which is a hallmark of immune system activation. In vivo intravenous treatment with a monoclonal anti-very late antigen (VLA)-1 antibody (HA31/8) significantly reduced the edema formation in the contralateral paw. T cells isolated from contralateral paw draining lymph nodes of FA rats treated with HA31/8 showed a reduced cell proliferation in vitro, after stimulation with concanavalin A. Furthermore FACS analysis showed that the reduction in proliferation was concomitant to a reduction in the number of T cells positive to surface IL-2 receptor expression. Our data indicate that after in vivo treatment with a monoclonal anti-very late antigen-1 antibody, there is a beneficial effect on the development of the secondary lesion, which correlates to the reduced ability of T cells to proliferate in vitro as well as to a reduced surface expression of IL-2 receptor. The association of this antibody to other drugs interfering at other levels in rheumatoid arthritis may open a new therapeutic window.

Animals↗

NO-naproxen modulates inflammation, nociception and downregulates T cell response in rat Freund's adjuvant arthritis.

1. Anti-inflammatory non steroidal drugs releasing NO (NO-NSAIDs) are a new class of anti-inflammatory drugs to which has been added an NO-releasing moiety. These compounds have been shown to retain the anti-inflammatory, analgesic and antipyretic activity of the parent compound but to be devoid of gastrointestinal (GI) toxicity. 2. Freund's adjuvant (FA) arthritis was induced in rats by a single intraplantar injection into the right hindpaw of 100 microl of mycobacterium butirricum (6 mg ml(-1)). The effect of equimolar doses of naproxen (1, 3 and 10 mg kg(-1)) and NO-naproxen (1.5, 4.5 and 16 mg kg(-1)) was evaluated using two dosage regimen protocols: (i) preventive, starting oral administration of the drugs at the time of induction of arthritis and for the following 21 days (day 1 - 21); (ii) therapeutic, starting oral administration of the drugs 7 days after adjuvant injection and for the following 14 days (day 7 - 21). 3. Hindpaw swelling (days 3, 7, 11, 14, 17, 21) and nociception (days 15 and 21) were measured. On day 22 rats were sacrificed, draining lymph nodes were removed and T cells isolated. In vitro proliferation of T cells following stimulation with concanavalin A (0.5 - 5 microg ml(-1)) was measured using a tritiated thymidine incorporation assay. IL-2 receptor expression on T cells was measured by FACS analysis. 4. Naproxen and NO-naproxen showed similar activity in reducing oedema formation in the non-injected (controlateral) hindpaw. Both drugs showed anti-nociceptive effect. NO-naproxen was anti-nociceptive at a dose of 4.5 mg kg(-1) while naproxen showed the same extent of inhibition only at a dose of 10 mg kg(-1). 5. T cells were isolated and characterized by FACS analysis. Stimulation of isolated T cells with concanavallin A in vitro caused a significant increase in thymidine uptake. NO-naproxen at a dose of 4.5 mg kg(-1) inhibited T cell proliferation to the same extent as 10 mg kg(-1) of naproxen. 6. Inhibition of T cell proliferation was well correlated with reduced IL-2 receptor expression on T cells. In addition, NO-naproxen reduced both IL-1beta and TNFalpha plasma levels whilst naproxen reduced IL-1beta levels only. 7. In conclusion, both naproxen and NO-naproxen reduce inflammation and nociception associated with arthritis. In addition NO-naproxen interferes to a larger extent with cellular mechanism involved in T cell activation in rat adjuvant arthritis indicating that introduction of the NO moiety in the naproxen structure increases the effect at the level of the immune system.

Animals↗