The pathway of estradiol-induced apoptosis in patients with systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is a disease with unknown etiology. The pathologic role of sex hormones and apoptosis in SLE has often been discussed. We studied the effects of estradiol in the pathway of induced apoptosis in Iranian SLE patients. T lymphocytes from 35 SLE patients and 20 age-matched controls were isolated and cultured in the presence of 10⁻⁸ M 17-β estradiol. The expression levels of Fas, Fas ligand (FasL), Bcl-2, caspase-8, and caspase-9 mRNAs were determined semiquantitatively in comparison to the expression level of beta actin RNA. Estradiol exposure did not have any significant effects on the expression levels of Fas, Bcl-2, and caspase-9 in SLE patients and controls. However, the expression levels of FasL and caspase-8 were significantly increased in SLE patients, but not in controls. This suggests the probable involvement of extrinsic apoptosis pathway in estradiol-induced apoptosis in SLE.     

Impaired natural killer cell function in systemic lupus erythematosus

Immune regulation requires clonal expansion of regulatory T cells which is dependent on the presence of interleukin-2 (IL-2). Previously, both natural killer (NK) cell function and IL-2 production were found to be depressed in systemic lupus erythematosus (SLE). This study was designed to determine the relationship between IL-2 production and NK cell activity in SLE. NK activity as determined by a standard 4-hour ⁵¹Cr-release assay was impaired in SLE (11.0 ± 5.1 lytic units/10⁷ cells) compared with controls (25.1 ± 7.1 lytic units/10⁷ cells) (P < 0.05). IL-2 production was induced with concanavalin A and phorbol ester and quantitated using the IL-2 dependent cell line HT-2. IL-2 production was impaired in only 1 SLE patient, despite concomitant abnormalities in NK function in the SLE group as a whole. Moreover, in patients with impaired NK activity, incubation of lymphocytes with exogenous IL-2 did not restore NK activity to normal levels. These findings demonstrate that impaired NK activity in SLE is independent of IL-2 production and that defects in IL-2 production in SLE may not be as common as previously reported.     

Dural sinus thrombosis: a mechanism for pseudotumor cerebri in systemic lupus erythematosus

We report a young woman with systemic lupus erythematosus complicated by pseudotumor cerebri which resolved with high dosage corticosteroid therapy. The cause of the raised intracranial pressure proved to be thrombosis of the torcular herophili and lateral sinuses. Despite laboratory evidence of a hypercoagulable state, the presence of a lupus anticoagulant could not be shown.     

Endothelial function is associated with myocardial diastolic function in women with systemic lupus erythematosus

Endothelial dysfunction is associated with traditional and systemic lupus erythematosus (SLE)-specific risk factors, and early data suggest reversibility of endothelial dysfunction with therapy. The clinical relevance of endothelial function assessment has been limited by the lack of studies, demonstrating its prognostic significance and impact on early myocardial function. Therefore, we aimed to determine the association between endothelial and myocardial diastolic function in SLE women. Women with SLE and no coronary artery disease were prospectively recruited and underwent radionuclide myocardial perfusion imaging (MPI) (Jetstream, Philips, the Netherlands) to exclude subclinical myocardial ischemia. Cardiac and vascular functions were assessed in all patients (Alpha 10, Aloka, Tokyo). Diastolic function was assessed using pulse wave early (E) and late mitral blood inflow and myocardial tissue Doppler (mean of medial and lateral annulus e′) velocities. Endothelial function was measured using brachial artery flow-mediated vasodilatation (FMD%). Univariate and multivariate linear regressions were used to assess the association between FMD% and myocardial diastolic function, adjusting for potential confounders. Thirty-eight patients without detectable myocardial ischemia on MPI were studied (mean age 44 ± 10 years; mean disease duration 14 ± 6 years). About 61 % of patients had normal diastolic function (E/e′ ≤ 8), and 5 % of patients had definite diastolic dysfunction with E/e′ > 13 (mean 7.1 ± 2.9). FMD% was associated with E/e′ (regression coefficient β = ?0.35; 95 % CI ?0.62 to ?0.08; p = 0.01) independent of systolic blood pressure, age, and SLICC/ACR Damage Index.     

Lymphocyte apoptosis and macrophage function: correlation with disease activity in systemic lupus erythematosus

Increased lymphocyte apoptosis and defects in macrophage removal of apoptotic cells have been suggested to contribute to the development of systemic lupus erythematosus (SLE). The aim of this study was to investigate the relationship between peripheral lymphocyte apoptosis, macrophage function as determined by the serum levels of neopterin and interferon- (IFN-), and SLE disease activity. Peripheral apoptotic lymphocytes (AL) were detected by annexin V-fluorescein isothiocyanate (FITC) staining and flow cytometry. Serum levels of neopterin and IFN- were measured by enzyme-linked immunosorbent assay (ELISA). SLE disease activity was determined using the systemic lupus activity measure (SLAM) and the serum titer of anti-dsDNA antibodies. The percentage of AL in the peripheral blood of active SLE patients was significantly higher (13.07±7.39%, n=30) than that of the inactive SLE patients (4.08±3.55%, n=8, p<0.01) and normal controls (5.13±3.37%, n=11, p<0.01). Serum levels of neopterin in active SLE patients were significantly higher (1.39±1.10 g/dl, n=22) than in controls (0.26±0.19 g/dl, n=20, p<0.01). Serum levels of IFN- in active SLE patients were elevated (58.97±34.52 ng/l, n=15) when compared with controls (28.06±2.35 ng/l, n=16, p<0.05). The percentage of AL correlated significantly with serum levels of neopterin (r=0.446, p<0.05, n=22) and SLAM score (r=0.533, p<0.001, n=38), but not with the serum levels of IFN-. The SLAM score also correlated with the serum levels of neopterin (r=0.485, p<0.05, n=22), but not with those of IFN-. Our study supported the hypothesis that increased lymphocyte apoptosis has a pathogenic role in SLE. The increased levels of serum neopterin may suggest an attempt of the patients macrophage system to remove the apoptotic cell excess. Since serum levels of neopterin correlated with the overall lupus disease activity, they may be regarded as an index of SLE disease activity.     

Peripheral vascular disease in systemic lupus erythematosus

With increasing longevity of lupus patients, peripheral vascular disease (PVD) has become an important cause of morbidity. With no systematic study of PVD in systemic lupus erythematosus (SLE), this study was undertaken to define the frequency and spectrum of PVD in SLE and factors affecting such an occurrence. All medium-sized peripheral arteries of bilateral upper and lower extremities were studied in 50 SLE patients using Doppler ultrasonography. PVD was defined clinically as one or more of intermittent claudication, absent/unequal pulses, gangrene or ischemic ulcers and sub-clinically as asymptomatic patients with Doppler abnormalities, with > or =50% reduction in diameter considered hemodynamically significant. Mean (SD) age of the patients was 31.6 (10.1) years. Forty-one percent were hypertensive. Dyslipidemia was found in 62%. Fifteen (30%) had Raynaud's phenomenon. Fourteen (28%) patients had PVD, of whom three had positive markers for antiphospholipid antibody (aPL) and six were asymptomatic. Ischemic ulcers were seen in eight (16%), gangrene in three (6%), femoral artery plaques in two (4%), stenosis in four (8%) and intermittent claudication in none. Dyslipidemia was found to independently affect occurrence of PVD (OR = 5.37, [95% CI 1.05-27.5], P = 0.05). The causes of PVD overlap significantly and further studies are needed to ascertain the relative contribution of each.     

Interferon pathway activation in systemic lupus erythematosus

The recognition that a multitude of interferon (IFN)-inducible genes are coordinately expressed in peripheral blood cells of patients with systemic lupus erythematosus (SLE) has contributed to considerable interest in the IFN pathway as a therapeutic target in lupus. Together with data that have accumulated over the past four decades implicat-ing IFN-á in SLE, the gene expression data have resulted in emergence of this cytokine pathway as a focal point for understanding mechanisms of autoimmunity and inflamma-tion in systemic autoimmune diseases. Assays that measure IFN-inducible gene expression in patient cells and tissues and plasma assays that quantify IFN-á protein are providing tools for identification of patients with active disease and who may be responsive to inhibition of the innate immune system component of the altered immune response in SLE. In addition, investigations of the mecha-nisms of induction of IFN pathway activation are suggesting clues to the triggers of autoimmunity in SLE.     

Haemostatic factors associated with vascular thrombosis in patients with systemic lupus erythematosus and the lupus anticoagulant.

To elucidate the mechanism of vascular thrombosis in patients with systemic lupus erythematosus and the lupus anticoagulant changes in factors associated with haemostasis were investigated. The lupus anticoagulant was associated with an increased incidence of thrombosis, particularly cerebral thrombosis. Concentrations of fibrinopeptide A and fibrinopeptide B beta 15-42 were significantly raised in the plasma of patients with systemic lupus erythematosus and the anticoagulant compared with concentrations in patients without the lupus anticoagulant. The tendency towards formation of thrombosis was not found in all lupus patients with the anticoagulant, however. Concentrations of thromboxane B2 were remarkably raised in the plasma of the two patients with the lupus anticoagulant who had recently had thrombosis. Concentrations of 6-keto-prostaglandin F1 alpha, protein C, antithrombin III, and plasminogen were similar in both groups. No significant decrease in serum stimulatory activity on prostacyclin production by cultured aortic endothelial cells was noted in lupus patients with the anticoagulant, but inhibition was present in the two patients with recent thrombosis. These results indicate that although patients with the lupus anticoagulant are not always in a hypercoagulable state, haemostatic abnormalities found in some patients with the anticoagulant may be predictive of thrombotic events.     

Indications of vascular endothelial cell dysfunction in systemic lupus erythematosus.

Fibrinolytic and other factors have been measured in 73 patients with systemic lupus erythematosus or related conditions to determine whether clinical thrombosis, a common feature of these disorders, is associated with defective fibrinolysis. Twenty five of 72 (35%) patients, compared with two of 22 (9%) controls, showed a low level of plasminogen activator activity in response to venous occlusion, suggesting decreased fibrinolytic potential. In addition, mean plasma levels of von Willebrand factor antigen and fibronectin were markedly raised in the patients (mean (SD) 384.5 (277)% and 727 (436) mg/l respectively) compared with healthy controls (100 (50)% and 306 (65) mg/l). These data suggest a degree of endothelial cell dysfunction. No clear correlation was found between a history of thrombosis and any plasma factor measured, except for prolongation of clotting tests suggestive of the 'lupus anticoagulant'.     

Renal vein thrombosis and inferior vena cava thrombosis in systemic lupus erythematosus

Phlebography of the inferior vena cava with selective study of the renal veins was performed in 43 patients with systemic lupus erythematosus (SLE). Inferior vena cava thrombosis (IVCT) or renal vein thrombosis (RVT) was found in 3 of 11 patients (27%) with nephrotic syndrome, in 8 of 13 (61.5%) with previous thrombophlebitis, and in 3 of 4 (75%) with suggestive acute clinical picture. In contrast, none of the 20 control patients with SLE had IVCT or RVT. These results show that SLE patients with thrombophlebitis have a very high risk of developing IVCT or RVT; patients with nephrotic syndrome have a smaller risk. Neither IVCT nor RVT was found in SLE patients without antecedent thrombophlebitis or nephrotic syndrome.     

Endothelial cell-binding antibodies in patients with systemic lupus erythematosus

 The implications of endothelial cell-binding IgG antibodies (EC IgG) in systemic lupus erythematosus (SLE) was evaluated by determining level of EC IgG in sera from 112 SLE patients. The serum EC IgG level was determined by the cyto-ELISA method using human umbilical vein endothelial cells (HUVEC), human microvascular endothelial cells (HMVEC), and aortic endothelial cells (HAEC) as antigens. The levels of EC IgG were significantly higher among patients with SLE than among healthy control subjects (P < 0.001), and 68% (76/112) of SLE patients were shown to be EC IgG-positive. In patients with active lupus nephritis, the level of EC IgG was statistically and significantly elevated compared with those without lupus nephritis (P < 0.05). Negative correlations between EC IgG level and levels of CH50, C3, and lymphocyte count were revealed (P < 0.05, P < 0.005, and P < 0.05, respectively). When clinical course was evaluated, the levels of EC IgG correlated with disease activity. Definitive correlations in antibody levels between HUVEC and HMVEC, and between HUVEC and HAEC were revealed (both P < 0.0001). The results of this study revealed that the EC IgG in patients with SLE was involved in the onset of clinical manifestation, especially in patients with active lupus nephritis. Received: January 28, 2002 / Accepted: July 12, 2002 Acknowledgments This investigation was supported by grants from the Research Committee on Intractable Vasculitides, and the Ministry of Health and Welfare of Japan, from 1996 to 2000. Correspondence to:H. Bando     

Multiorgan thrombotic disorders in systemic lupus erythematosus: a common link?

Multiorgan thrombotic disorders have been described in a variety of conditions including systemic lupus erythematosus. Among these are the 'catastrophic' antiphospholipid syndrome, disseminated intravascular coagulation and the thrombotic thrombocytopenic purpura-haemolytic uraemic syndrome. In this review we briefly analyse some specific clinical and haematological characteristics of these conditions and attempt to uncover common links between them.     

Mechanisms of abnormal platelet aggregation in systemic lupus erythematosus

Platelet aggregation was measured in 14 patients with systemic lupus erythematosus (SLE) and 13 normal controls. Ten SLE patients (group I) showed decreased responsiveness to collagen, while aggregation was normal in 4 (group II). Group I patients also responded poorly to epinephrine. Platelets from SLE patients did not differ from controls in the production of malondialdehyde in response to N-ethylmaleimide, suggesting intact prostaglandin synthetic pathways. However, a significant decrease (P < 0.005) in platelet levels of the dense granule constituent, serotonin, was noted in group I SLE patients. Treatment of SLE platelet-rich plasma with deoxyribonuclease (DNase) resulted in enhancement of collagen-induced aggregation in 4 group I SLE patients, but not in 1 group II or 8 normal individuals. These results suggest that defective aggregation in SLE platelets may be partially related to a storage pool deficiency state. However, the ability to restore aggregation to collagen by digestion of platelet-rich plasma with DNase indicates that the defect is reversible and that it is perhaps mediated by plasma or platelet-associated DNA.     

Cognitive function in a systemic lupus erythematosus inception cohort

OBJECTIVE: Measurable cognitive impairment occurs in 30-75% of patients with systemic lupus erythematosus (SLE). We compared cognitive functioning in recently-diagnosed SLE patients and normal controls. METHODS: The Automated Neuropsychological Assessment Metrics (ANAM), a repeatable computerized cognitive battery assessing cognitive processing speed and efficiency, was administered to 111 recently diagnosed SLE patients and 79 normal controls. Throughput scores on ANAM subtests were compared using linear regression. RESULTS: After adjusting for age, gender, ethnicity, and education, SLE patients scored significantly lower than controls on throughput measures of 4 ANAM subtests: code substitution immediate recall (p = 0.02), continuous performance (p = 0.02), matching to sample (p = 0.02), and Sternberg subtest (p = 0.0002). CONCLUSIONS:Recently diagnosed SLE patients performed significantly worse than normal controls on 4 of 9 ANAM subtests. ANAM subtests of cognitive efficiency requiring sustained attention/vigilance, visuospatial span of attention/working memory, and simple reaction time showed the greatest impairment. These cognitive deficits were particularly striking, because the SLE patients in this sample were not selected for the presence of neuropsychiatric manifestations, had mild SLE-related disease/damage, and were recently diagnosed with SLE. This suggests that deficits in cognitive efficiency and sustained attention are present early in the course of SLE and in the absence of other significant neuropsychiatric manifestations.