Cardiometabolic and immune factors associated with increased common carotid artery intima-media thickness and cardiovascular disease in patients with systemic lupus erythematosus.

BACKGROUND AND AIM: Patients with systemic lupus erythematosus (SLE) have a higher prevalence of subclinical atherosclerosis and higher risk of cardiovascular (CV) events compared to the general population. The relative contribution of CV-, immune- and disease-related risk factors to accelerated atherogenesis in SLE is unclear. METHODS AND RESULTS: Fifty SLE patients with long-lasting disease (mean age 44 ± 10 years, 86% female) and 50 sex- and age-matched control subjects were studied. Common carotid artery intima-media thickness (CCA-IMT) was used as a surrogate marker of atherosclerosis. We evaluated traditional and immune- and disease-related factors, assessed multiple T-cell subsets by 10-parameter-eight-colour polychromatic flow cytometry and addressed the effect of pharmacological therapies on CCA-IMT. In SLE patients, among several cardiometabolic risk factors, only high-density lipoprotein levels (HDL) and their adenosine triphosphate-binding cassette transporter 1 (ABCA-1)-dependent cholesterol efflux capacity were markedly reduced (p < 0.01), whereas the CCA-IMT was significantly increased (p = 0.03) compared to controls. CCA-IMT correlated with systolic blood pressure, low-density lipoprotein (LDL) cholesterol and body mass index (BMI), but not with disease activity and duration. The activated CD4(+)HLA-DR(+) and CCR5(+) T-cell subsets were expanded in SLE patients. Patients under hydroxychloroquine (HCQ) therapy showed lower CCA-IMT (0.62 ± 0.08 vs. 0.68 ± 0.10 mm; p = 0.03) and better risk-factor profile and presented reduced circulating pro-atherogenic effector memory T-cell subsets and a parallel increased percentage of naïve T-cell subsets. CONCLUSION: HDL represents the main metabolic parameter altered in SLE patients. The increased CCA-IMT in SLE patients may represent the net result of a process in which 'classic' CV risk factors give a continuous contribution, together with immunological factors (CD4(+)HLA-DR(+) T cells) which, on the contrary, could contribute through flares of activity of various degrees over time. Patients under HCQ therapy present a modified metabolic profile, a reduced T-cell activation associated with decreased subclinical atherosclerosis.

High density lipoprotein cholesterol levels are an independent predictor of the progression of chronic kidney disease.

OBJECTIVES: Patients with chronic kidney disease (CKD) often present with reduced plasma HDL cholesterol (HDL-C) levels. Whether this reduction in an epiphenomenon or is involved in disease progression is unclear. The aim of this study was to investigate the relation between HDL-C levels/function and CKD progression in patients with different degrees of disease. DESIGN: A total of 176 patients with CKD [glomerular filtration rate (GFR) 50.3 ± 29.1 mL min⁻¹] were recruited and followed for up to 84 months. Lipid profile, metabolic status and kidney function were evaluated at predetermined times. Age-matched control subjects were selected from the PLIC study (n = 453). Scavenger receptor class B member 1 (SR-BI) and ATP-binding cassette transporter A1 (ABCA-1)-dependent efflux of cholesterol were measured in CKD patients and in age-matched control subjects. RESULTS: Low HDL-C levels, diabetes and hypertension were associated with reduced GFR. At follow-up, low HDL-C levels were associated with earlier entry in dialysis or doubling of the plasma creatinine level (P = 0.017); HDL-C levels were the only lipid parameter that affected the progression of CKD (hazard ratio 0.951, 95% confidence interval 0.917-0.986, P = 0.007), independently of the presence of diabetes. Only SR-BI-mediated serum cholesterol efflux was significantly reduced in the group of CKD patients with low HDL-C levels compared to the control group. CONCLUSIONS: CKD patients with low levels of plasma HDL-C have a poor prognosis. HDL functionality is also impaired in renal dysfunction. These data support the relevance of HDL in influencing CKD progression.

Liver X receptor and retinoic X receptor agonists modulate the expression of genes involved in lipid metabolism in human endothelial cells.

The cooperation of liver X receptors (LXRs) alpha and beta, and retinoic X receptor (RXR) modulate the expression of several genes involved in lipid metabolism in hepatocyte and macrophages. Using cDNA microarray technology, we have shown previously that several of these genes are also expressed in endothelial cells. In the present study, we investigated whether the activation of LXR and RXR affects the expression of genes involved in lipid metabolism in human endothelial cells. Relative expression of ABCA-1, CETP, SR-B1, EL, LPL, PLTP, ApoE and LDLR was investigated in HUVECs, human fibroblasts (hFB) and HepG2 cells by quantitative real-time PCR. For CETP and EL mRNA expression, the results were HUVECs > hFB > HEPG2; for PLTP, LDLR and LPL: hFB > HUVECs > HEPG2; for SR-B1 and ApoE: HEPG2 > HUVECs > hFB; and for ABCA-1 HEPG2: > hFB > HUVECs. Incubation of HUVECs with LXR agonists as 22-(R)-hydroxycholesterol (22-(R)-HC) or T0901317-induced ABCA1 (20.1- and 17.8-fold), LPL (3.46- and 7.03-fold) and CETP (6.34- and 3.98-fold) expression; EL, LDLR and SR-B1 expression was induced only upon incubation with T0901317 (2.40-, 2.83- and 2.19-fold, respectively) while 22-(R)-HC had no effect on EL and SR-B1 expression (0.8- and 0.9-fold) and decreased LDLR expression (0.4-fold). No effect of either 22-(R)-HC or T0901317 on PLTP and ApoE expression was observed. The RXR agonist, 9-cis retinoic acid (9CRA) alone induced the expression of CETP, LPL and SR-B1 (2.8-, 8.2- and 2.4-fold). No effect of 9CRA on ABCA-1, EL, PLTP, ApoE, and LDLR expression was observed. Association of 9CRA with 22-(R)-HC or T0901317 increased the expression of CETP and LPL while no effect on ABCA-1 or LDLR was observed. Activation of LXRs and RXRs in endothelial cells represents a new target of LXR and RXR agonist in the arterial wall. Modulation of gene expression in the endothelium should be taken into account when studying the effects of LXR and RXR agonists on lipid metabolism in the arterial wall.

Solitary thyroid metastasis from colon cancer: fine-needle aspiration cytology and molecular biology approach.

Thyroid gland is one of the most vascularized organs of the body, nevertheless clinical and surgical series report an incidence of secondary malignancies in this gland of only 3%. Colorectal carcinoma metastatic to the thyroid gland is not as uncommon as previously believed, infact the number of cases seems to be increased in recent years due to the more frequent use of fine-needle aspiration cytology (FNAC) guided by ultrasonography. Although kidney, breast and lung metastases to the thyroid are frequent, metastasis from colon cancer is clinically rare with 52 cases reported in the literature in the last 5 decades and three cases described as solitary thyroid metastasis from the colon cancer without any other visceral metastases. To the best of our knowledge, we report the fourth case of solitary, asymptomatic thyroid metastasis from colon cancer without involvement of other organs. We discuss the importance of FNAC to detect metastatazing process as a compulsory step of the diagnostic and therapeutic management algorithm, combined with a molecular biology approach. A review of the last 5 decades literature, to update the number of cases described to date, is also included.

Immunoreactivity of apo B towards monoclonal antibodies that inhibit the LDL-receptor interaction: effects of LDL oxidation.

We studied the immunochemical stability of the epitopes for six monoclonal antibodies to human apolipoprotein B-100 upon Cu(2+)-mediated (20 microM) oxidation of LDL. The antibodies used in this study, some of which are known to interfere with the interaction of LDL with their cellular receptors, recognize epitopes in the amino terminal region (Mb 19), in the middle part (6B, 2A, 7A, and 9A) and near aa 3500 (Mb 47) of native apo B. All antibodies except one (7A) recognized native and oxidized LDL (OxLDL) equally well; the immunoreactivity of the epitope for Ab 7A was markedly reduced upon LDL oxidation. Since antibodies 2A, 7A, 9A, and Mb 47 inhibit the LDL-receptor interaction and OxLDL poorly interact in vitro with the LDL receptor we conclude that: (1) various epitopes for monoclonal antibodies against native apo B are spared upon LDL oxidation; and (2) the epitopes for antibodies 2A, 9A, and Mb 47 do not define a unique domain of apo B directly involved in the binding of LDL to their receptor.

Epitope mapping analysis of apolipoprotein B-100 using a surface plasmon resonance-based biosensor.

Using a surface plasmon resonance (SPR)-based biosensor (BIA-technology), we have studied the interaction of ten different murine monoclonal antibodies (mAbs, all IgG(1)), raised against the main protein constituent of human low density lipoprotein (LDL), i.e. the apolipoprotein B-100 (apoB-100). These mAbs identify distinct domains on apoB-100, relevant to LDL-receptor interaction: epitopes in the amino-terminal region (mAbs L7, L9, L10 and L11: aa 1-1297) and in the middle region (mAb 6B: aa 1480-1693; mAbs 2A, 3B: aa 2152-2377; mAbs 9A, L2 and L4: aa 2657-3248) of native apoB-100. A multisite binding analysis was performed to further characterize the epitopes recognized by all these mAbs. A rabbit anti-mouse IgG(1)-Fc antibody (RAM.Fc) was first coupled to the gold surface in order to capture one anti-human apoB-100 mAb. ApoB-100 protein was subsequently injected and allowed to react with this immobilized, oriented antibody. Multisite binding assays were then performed, by sequentially flowing other mAbs, in different orders, over the sensing surface. The capacity of each mAb to interact with the entrapped apoB-100 in a multimolecular complex was monitored in real time by SPR. The results achieved were comparable to those obtained by western immunoblotting using the same reagents. However, SPR ensures a more detailed epitope identification, demonstrating that BIA-technology can be successfully used for mapping distinct epitopes on apoB-100 protein in solution dispensing with labels and secondary tracers; moreover, compared with conventional immunoassays, it is significantly time saving (CNR-P.F. MADESS 2).

Nucleolar protein p120 expression in oral carcinoma.

Nucleolar protein p120 is a proliferation-associated antigen expressed by cells in early G1 phase, identified by the monoclonal antibody FB-2. Its expression has been evaluated in breast and prostate cancer, and proved to be significantly correlated with other prognostic parameters. In oral pathology, p120 protein content is able to distinguish between non-neoplastic and malignant lesions. In the present study, the immunohistochemical expression of p120 protein was evaluated in fifty cases of oral squamous carcinoma and compared with histological grading, pTNM staging, DNA ploidy status and follow-up of the patients, in order to establish its prognostic value, p120 mean area was significantly correlated to all these parameters, apart from lymph node involvement, indicating the strong predictive potential of this marker. In conclusion, quantitative immunohistochemical analysis of p120 protein represents an easy and reliable method for the assessment of clinical outcome and the definition of risk groups in oral carcinoma.

Intestinal tuberculosis: a diagnostically-challenging case misdiagnosed as Crohn's disease at colorectal biopsy.

The clinical presentation of two different digestive diseases such as Crohn's disease and intestinal tuberculosis may be so similar to induce a delay in correct diagnosis and appropriate treatment (immune suppression versus antibiotic therapy). Herein, we describe the case of a young man from Eastern Europe who came to our observation complaining of clinical symptoms initially misdiagnosed as an inflammatory bowel disease. It is important to keep in mind the possibility of an active tubercular disease, particularly in patients coming from countries endemic for the disease. Morphological findings of sarcoid-like granulomas at biopsy is not enough for a conclusive diagnosis of Crohn's disease, and tuberculosis should be ruled out on the basis of clinical information, laboratory tests and radiological imaging.

A solitary polypoid gastric metastasis 20 years after renal cell carcinoma: an event to be considered, and a brief review of the literature.

BACKGROUND: The incidence of gastric metastasis is 2.6%. Although all primary neoplasms can metastasize to the stomach, most originate from melanoma or breast and lung cancer. Their most common endoscopic appearance is a "volcano-like" polypoid mass covered by normal mucosa that may show a central ulceration. Renal cell carcinoma, clear cell type, is known to spread hematogenously, and isolated metastasis to the stomach is a rare event. CASE PRESENTATION: In this report, we describe a gastric recurrence of RCC, clear-cell type, in a 80-year-old patient who had undergone nephrectomy 20 years before. We also performed a brief review of the literature to update the number of cases described to date. CONCLUSION: Metastatic involvement of the stomach should be suspected in any patient with a previous history of renal cell carcinoma, clear cell type, presenting with gastrointestinal symptoms, even if many years after nephrectomy. The peculiarity of our case is due to the very late presentation of the gastric metastasis. Only two cases of very late gastric metastases from RCC, clear cell type, have been described in the literature, to date.

Leiomyomatosis peritonealis disseminata: pregnancy, contraception and myomectomy of its pathogenesis.

Leiomyomatosis peritonealis disseminata (LPD) is a rare smooth muscle tumour characterized by multiple small nodules on the omentum and peritoneal surface, composed of benign smooth muscle cells with minimal mitotic activity, frequently admixed with decidual cells. The possible pathogenetic mechanisms include hormonal dysfunction, differentiation of subperitoneal mesenchymal stem cells, myofibroblastic metaplasia and genetic and iatrogenic causes (resection of myomas during laparoscopic surgery). Diagnosis is easily made on biopsy specimens. Reduction of oestrogen exposure, surgical castration or gonadotrophin releasing hormone agonists are generally sufficient to cause regression of LPD. We report a case of an asymptomatic 36-year-old pregnant woman with long-term use of oral contraceptives, and previous myomectomy, who had a mass of uncertain origin which was, histopathologically, diagnosed as leiomyomatosis peritonealis diffusa with foci of ectopic decidua. Ectopic decidua was also present in a pelvic lymph node. To the best of our knowledge, this is the first case of LPD containing foci of ectopic decidua in a pregnant woman with a past history of myomectomy and use of oral contraception for three years; ectopic decidua was also detected in a pelvic lymph node.

Increased atherosclerosis and vascular inflammation in APP transgenic mice with apolipoprotein E deficiency.

OBJECTIVE: Atherosclerosis is associated with Alzheimer's disease (AD) in humans, but the nature of this link is still elusive. Aim of this study was to investigate aortic atherosclerosis development in a mouse model with central nervous system (CNS) restricted beta-amyloid precursor protein (APP) overexpression. METHODS AND RESULTS: APP23 mice, overexpressing the Swedish mutated human APP selectively in the brain, were crossed with mice lacking apolipoprotein E (ApoE KO). Nine weeks old mice were fed a western type diet for eight weeks, then atherosclerotic lesions, aortic wall and cortical tissues gene expression and beta-amyloid (Abeta) deposition were evaluated. Compared with ApoE KO, APP23/ApoE KO mice developed larger aortic atherosclerotic lesions and showed significantly increased expression of MCP-1, IL-6, ICAM-1 and MTPase 6, a marker of oxidative stress in the vascular wall. Of note brain limited APP synthesis was associated with an increased microglia and brain endothelial cells activation, in spite of the absence of beta-amyloid deposits in the brain or alteration in the levels of oxidized metabolites of cholesterol such as 4-cholesten-3-one. CONCLUSION: Our study suggests that the vascular pro-inflammatory effects of CNS-localised APP overexpression lead to atherogenesis before parenchymal Abeta deposition and neuronal dysfunction.

Localization of apolipoprotein A-I epitopes involved in the activation of lecithin:cholesterol acyltransferase.

Eight murine monoclonal antibodies (Mab) to apolipoprotein A-I were characterized for their epitopes and for their ability to interfere with lecithin:cholesterol acyltransferase (LCAT) activation mediated by apo apoA-I using a synthetic substrate. Using overlapping synthetic peptides we have identified six continuous epitopes that span amino acids 1-10 (Mab A-I-19), 96-101 (Mab A-I-15), 133-141 (Mab A-I-5), 140-145 (Mab A-I-9), 144-148 (Mab A-I-8), and 167-174 (Mab A-I-57). Furthermore, antibodies A-I-11 and A-I-16 recognized discontinuous epitopes, namely amino acids 124-128 and 144-148. When antibodies were tested for their ability to inhibit LCAT activation, an inhibitory effect was observed with those whose epitopes covered the area of apoA-I encompassing amino acids 96-174. From these data we conclude that several areas of apoA-I spanning the middle region of the apolipoprotein act in concert to stimulate LCAT activity, possibly by cooperative interaction with the enzyme.

Identification of domains in apoA-I susceptible to proteolysis by mast cell chymase. Implications for HDL function.

When stimulated, rat serosal mast cells degranulate and secrete a cytoplasmic neutral protease, chymase. We studied the fragmentation of apolipoprotein (apo) A-I during proteolysis of HDL(3) by chymase, and examined how chymase-dependent proteolysis interfered with the binding of eight murine monoclonal antibodies (Mabs) against functional domains of apoA-I. Size exclusion chromatography of HDL(3) revealed that proteolysis for up to 24 h did not alter the integrity of the alpha-migrating HDL, whereas a minor peak containing particles of smaller size with prebeta mobility disappeared after as little as 15 min of incubation. At the same time, generation of a large (26 kDa) polypeptide containing the N-terminus of apoA-I was detected. This large fragment and other medium-sized fragments of apoA-I produced after prolonged treatment with chymase were found to be associated with the alphaHDL; meanwhile, small lipid-free peptides were rapidly produced. Incubation of HDL(3) with chymase inhibited binding of Mab A-I-9 (specific for prebeta(1)HDL) most rapidly (within 15 min) of the eight studied Mabs. This rapid loss of binding was paralleled by a similar reduction in the ability of HDL(3) to induce high-affinity efflux of cholesterol from macrophage foam cells, indicating that proteolysis had destroyed an epitope that is critical for this function. In sharp contrast, prolonged degradation of HDL(3) by chymase failed to reduce the ability of HDL(3) to activate LCAT, even though it led to modification of three epitopes in the central region of apoA-I that are involved in lecithin cholesterol acyltransferase (LCAT) activation. This differential sensitivity of the two key functions of HDL(3) to the proteolytic action of mast cell chymase is compatible with the notion that, in reverse cholesterol transport, intactness of apoA-I is essential for prebeta(1)HDL to promote the high-affinity efflux of cellular cholesterol, but not for the alpha-migrating HDL particles to activate LCAT.

Characterization of a family with moderate hypercholesterolemia and binding defective low density lipoprotein.

Familial defective apolipoprotein B-100 (FDB) is a genetic disorder presenting with hypercholesterolemia and abnormal low density lipoprotein (LDL) that binds poorly to LDL receptors. This disease appears to be caused by a mutation in the apo B gene. In the present study thirteen members of a family with moderate hypercholesterolemia (250-350 mg/dl) were investigated. Biochemical studies on cultured skin fibroblasts ruled out classical familial hypercholesterolemia (receptor deficiency). LDL from nine affected members displayed, in an "in vitro" cell binding assay, a reduced affinity (2.5 fold) for the receptor, and had normal electrophoretic mobility, size and chemical composition. Lp(a) levels in family members were comparable to those present in normolipidemics and lower than those observed in primary hypercholesterolemia. The disorder is transmitted over three generations as an autosomal codominant trait and all the affected members are heterozygotes and hypercholesterolemic.

Monoclonal antibodies to human low density lipoprotein identify distinct areas on apolipoprotein B-100 relevant to the low density lipoprotein-receptor interaction.

We have characterized the epitopes for ten murine monoclonal antibodies (Mabs) to human low density lipoprotein (LDL) and studied their ability to interfere with the LDL-receptor interaction. The epitopes for the antibodies were defined by using the following approaches: 1) interaction with apoB-48; 2) interaction with apoB-100 thrombolytic fragments; and 3) interaction with beta-galactosidase-apoB fusion proteins spanning different areas of the apoB-100 sequence. The results obtained are consistent with the following map of epitopes: Mab 6E, amino acids (aa) 1-1297, Mabs 5A and 6B, aa 1480-1693, Mabs 2A, 7A, 3B, and 4B, aa 2152-2377, Mabs 8A and 9A, aa 2657-3248 and 3H, aa 4082-4306. Four Mabs (2A, 5A, 7A, and 9A) whose epitopes are located in three different areas of apoB, dramatically reduced (up to 95%) the LDL-receptor interaction on cultured human fibroblasts; Fab fragments were as effective as the whole antibodies. Mab 3H, on the other hand, increased LDL binding up to threefold. These findings are consistent with the hypothesis that several areas of apoB-100 are involved independently or in concert in modulating the apoprotein B conformation required for interaction with the LDL receptor.

Treatment of severe hypercholesterolemia in apolipoprotein E-deficient mice by intramuscular injection of plasmid DNA.

We report on systemic delivery and long-term biological effects of apolipoprotein E (apoE) obtained by intramuscular (i.m.) plasmid DNA injection. ApoE plays an important role in lipoprotein catabolism and apoE knock-out mice develop severe hypercholesterolemia and diffuse atherosclerosis. We have injected apoE-deficient mice with 80 microg of a plasmid vector (pCMV-E3) encoding the human apoE3 cDNA under the control of the CMV promoter-enhancer in both posterior legs. Local expression of the transgene was demonstrated throughout 16 weeks. Human apoE3 recombinant protein reached 0.6 ng/ml serum level. After i.m. injection of pCMV-E3 expression vector the mean serum cholesterol concentrations decreased from 439 +/- 57 mg/dl to 253 +/- 99 mg/dl (P < 0.05) 2 weeks after injection and persisted at a significantly reduced level throughout the 16 weeks observation period (P < 0.005). Serum cholesterol was unaffected and reached an absolute level of 636 +/- 67 mg/dl in control groups. Finally, injection of pCMV-E3 into apoE-deficient mice resulted in a redistribution of cholesterol content between lipoprotein fractions, with a marked decrease in VLDL, IDL and LDL cholesterol content and an increase in HDL cholesterol. These results demonstrate that severe hypercholesterolemia in apoE-deficient mice can be effectively reversed by i.m. DNA injection, and indicate that this approach could represent a useful tool to correct several hyperlipidemic conditions resulting in atherosclerosis.