Influence of serum amyloid A protein on high-density lipoprotein in chronic inflammatory disease

The effect of the content of ApoA-I in peripheral blood on the state of immune homeostasis in people living in extreme climatic conditions of the Arctic

The paper presents data on the impacts of the content of ApoA-I in peripheral blood on the state of immune homeostasis in people living in extreme climatic conditions of the Arctic. From the village of Revda, Murmansk region, 191 people were examined, 160 women and 31 men, aged from 21 to 55 years. The analysis of the results was carried out depending on the level of ApoA-I content: 111 examined people had a low content of ApoA-I (< 115 mg/dl) and 80 people had a concentration of ApoA-I - within the physiological norm (115-220 mg/dl). Deficiency of ApoA-I is associated with an increase in plasma concentrations of total cholesterol in 37.5% and triglycerides in 62.5% of cases. Low content of ApoA-I is associated with a decrease in the content of neutrophilic granulocytes and an increase in the concentration of small lymphocytes, IL-10 and IgE. Deficiency of ApoA-I is associated with an increase in the content of CD45RA+, CD16+, CD56+ lymphocyte phenotypes in blood. Low concentrations of ApoA-I are associated with low expression activity of L-selectin gene and free L-selectin ligand. Due to deficiency of ApoA-I, no significant differences were detected in the content of transferrin, free transferrin receptor, haptoglobin, free calcium-dependent cell adhesion protein, and free pool of receptors involved in apoptosis. Conclusion: deficiency of ApoA-I in blood plasma is associated with increased migration of neutrophils into the tissue and cell-mediated cytotoxicity of lymphocytes and occurs because of the effect of decreased activity of the level of antioxidant defense, changes in the structure of cell membranes and the participation of adhesion molecules.

Mass spectral analysis of urine proteomic profiles of dairy cows suffering from clinical ketosis

BACKGROUND

Ketosis is an important metabolic disorder in dairy cows during the transition period. The urine proteomics of ketosis has not been investigated using surface-enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF-MS).

OBJECTIVE

The aim is to determine differences between urine proteomic profiles of healthy cows and those with clinical ketosis, and facilitate studies of the underlying physiological and biochemical mechanisms that lead to liver pathology in ketosis.

ANIMALS AND METHODS

We analyzed the urine samples of 20 cows with clinical ketosis (group 1) and 20 control cows (group 2) using SELDI-TOF-MS.

RESULTS

Thirty-nine peptide peaks differed between both groups. Polypeptides corresponding to 26 of these differential peptide peaks were identified using the SWISS-PROT protein database. We found that the peaks of 11 distinct polypeptides from the urine samples of the ketosis group were significantly reduced, compared with those of the control group as based on the Wilcoxon rank sum test. Among these were VGF (non-acronymic) protein, amyloid precursor protein, serum amyloid A (SAA), fibrinogen, C1INH, apolipoprotein C-III, cystatin C, transthyretin, hepcidin, human neutrophil peptides, and osteopontin.

CONCLUSION

These proteins may represent novel biomarkers of the metabolic changes that occur in dairy cows with ketosis. Our results will help to better understand the physiological changes and pathogenesis observed in cows with ketosis.

CLINICAL IMPORTANCE

The SELDI-TOF-MS can be used to understand the physiological and biochemical mechanisms of ketosis and identify biomarkers of the disease.

Rs12218 In SAA1 gene was associated with serum lipid levels

Background

Serum amyloid A (SAA) is a kind of apolipoprotein. Several studies indicated that SAA genetic polymorphism rs12218 was associated with carotid atherosclerosis, peripheral arterial disease, and serum uric acid levels. However, the relation between rs12218 and lipid levels remains unclear. This study assessed the correlation between SAA1 gene rs12218 polymorphism and lipid levels in a Chinese population.

Methods

A total of 823 participants were selected from the subjects for health check in Shanghai Huashan hospital from Jan. 2013 to Mach. 2013. Correlations between rs12218 polymorphism and lipid levels were investigated through the identification of rs12218 genotypes using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP).

Results

We found that the SNP rs12218 was associated with triglyceride (TG), total cholesterol (TC), and low-density lipoprotein (LDL-C) levels by analyses of a dominant model (P<0.001, P=0.002, P=0.003, respectively), a recessive model (P <0.001, P=0.001, P=0.005, respectively) and an additive model (P < 0.001, P=0.001, P=0.002, respectively), and the difference remained significant after the adjustment of sex, age, alcohol intake, and smoking (All P < 0.01).

Conclusion

Our results indicated that the rs12218 in the SAA1gene was associated with lipid levels in a Chinese population.

Determination of inflammatory biomarkers in patients with COPD: a comparison of different assays

Background

Chronic obstructive pulmonary disease (COPD) is an inflammatory pulmonary disorder with systemic inflammatory manifestations that are mediated by circulating acute-phase reactants. This study compared an enzyme-linked immunosorbent assay (ELISA) to a nephelometric technique for the measurement of serum C-reactive protein (CRP) and serum amyloid A (SAA) and investigated how the choice of assay influenced the estimation of inflammation in patients with stable COPD.

Methods

CRP and SAA concentrations measured by ELISA and nephelometry in 88 patients with COPD and 45 control subjects were used to evaluate the performance of these methods in a clinical setting.

Results

With both assays, the concentrations of CRP and SAA were higher in COPD patients than in controls after adjustment for age and sex. There was a moderate correlation between the values measured by ELISA and those measured by nephelometry (logCRP: r = 0.55, p < 0.001; logSAA: r = 0.40, p < 0.001). However, the concentrations of biomarkers determined by nephelometry were significantly higher than those obtained with ELISA for CRP (mean difference = 2.7 (9.4) mg/L) and SAA (mean difference = 0.31 (14.3) mg/L).

Conclusion

Although the serum CRP and SAA concentrations measured by ELISA and nephelometry correlated well in COPD patients, the ELISA values tended to be lower for CRP and SAA when compared with nephelometric measurements. International standardization of commercial kits is required before the predictive validity of inflammatory markers for patients with COPD can be effectively assessed in clinical practice.

Lipid Profile and Anticardiolipin Antibodies in Behcet's Disease

BACKGROUND

Behcet's disease (BD) is a multisystem disorder characterized by a relapsing inflammatory process of unknown etiology. It is well known that atherothrombosis in systemic inflammatory disorders is closely related to coagulation and lipid metabolism abnormalities. The purpose of this study was to investigate some parameters of lipid metabolism, lipoprotein (a) [Lp(a)] and anticardiolipin antibody (ACA) levels and the relationship of these parameters with the clinical activity of BD.

METHODS

Thirty three patients with BD (15 active, 18 inactive cases) and 20 healthy controls participated in the study. After performing a detailed physical exam, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), total cholesterol (TC), triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), very-low-density lipoprotein cholesterol (VLDL-C), apoprotein A and B (apo-A, apo-B), Lp(a), and ACA levels (ACA-IgG and IgM) were measured in all participants.

RESULTS

Patients with active BD had higher ESR, CRP and Lp(a) levels, and lower apo-A and HDL-C levels compared with the patients with inactive BD and healthy controls. ACA-IgG and IgM levels were higher in patients with active BD than healthy controls but not higher than patients with inactive BD. On the other hand, ACA-IgG level was higher in active and inactive cases with vascular involvement than in those of active and inactive cases without vascular involvement. In the analyses of correlation, in active BD patients we found a positive correlation between CRP and Lp(a) levels.

CONCLUSIONS

Our findings suggest that Lp(a) behaves as an acute phase reactant and ACA levels are increased in patients with active BD. Data from patients with active BD may be compatible with the serum profile, which is accepted as a risk for the development of atherothrombosis.

Human paraoxonase-1 gene expression by HepG2 cells is downregulated by interleukin-1beta and tumor necrosis factor-alpha, but is upregulated by interleukin-6

Recent studies have demonstrated that human paraoxonase-1 (PON1) associated with HDL, plays a role for anti-atherosclerotic effects of HDL, however, the relationships between PON1 and inflammatory cytokines remain unclear. To clarify this point, we evaluated the transcriptional regulation of PON1 gene by IL-1beta, IL-6 and TNF-alpha in HepG2 cells using luciferase reporter gene assay. We determined the nucleotide sequence of upstream of PON1 gene, and constructed plasmids containing various lengths of upstream region. In the plasmid constructs of U39 (PON1 upstream -1232/-6), U682 (-589/-6), U797 (-472/-6) and U953 (-318/-6), U953 showed a stepwise upregulation in basal promoter activity. The relative promoter activities using U682 plasmid were generally downregulated by IL-1beta and TNF-alpha, but were upregulated by IL-6. By the combination of IL-1beta, IL-6 and/or TNF-alpha, the promoter activities were proportionally regulated. The result of PON1 transcriptional regulation by cytokines in HepG2 cells was confirmed to be concordant with that of regulation of PON1 mRNA expression by cytokines. These results suggest that PON1 mRNA expression by hepatocytes is regulated by proinflammatory cytokines and that proinflammatory cytokines secreted in a disease state, may play a role in the development of atherosclerotic lesion via modification of PON1 mRNA expression affecting on the anti-oxidative property of HDL.

Marked reduction in serum high-density lipoprotein cholesterol concentrations in a woman with acute inflammation due to diabetic gangrene

BACKGROUND

C-reactive protein (CRP) is a well-established, sensitive marker of systemic inflammation and the risk of cardiovascular disease. High-density lipoprotein (HDL) is an anti-atherogenic lipoprotein known to be regulated by genetic and acquired factors.

METHODS

The patient was a 77-year-old Japanese woman, who was diagnosed with type 2 diabetes mellitus (DM), with a body height of 152 cm and a weight of 65 kg (body mass index 28.1 kg/m2). She suffered from diabetic foot gangrene in her right foot with high-grade fever when she visited our hospital. Her plasma glucose (PG) concentration and serum CRP were markedly elevated being 21.6 mmol/l and 370 mg/l, respectively, while her serum HDL-C concentrations were markedly low being 0.13 mmol/l. She was immediately admitted to our hospital and received intensive insulin treatment, along with intravenous-administration of antibiotics. Her general conditions were gradually improved and the high-grade fever disappeared, with concentrations of plasma PG and serum CRP being reduced, and concurrent reciprocal increase in her serum HDL-C concentrations.

RESULTS

To determine the potential causative factors responsible for the drastic change in serum HDL-C concentrations, we investigated the relationship of serum HDL-C to serum CRP, serum total protein (TP) and PG. Serum CRP and PG showed inverse relationships with serum HDL-C, while serum TP concentrations showed a positive association with HDL-C. After multivariate analyses with CRP, TP and PG as independent variables and serum HDL-C as dependent variable, CRP maintained its independent association with serum HDL-C. CRP also showed inverse correlations with lipoprotein lipase (LPL) mass and cholesteryl ester transfer protein mass.

CONCLUSIONS

In acute inflammation and poorly controlled diabetes, CRP is suggested to be inversely associated with serum HDL-C, independent of PG and TP.

Serum paraoxonase activity decreases in rheumatoid arthritis

OBJECTIVE

To estimate the alterations of paraoxonase 1 (PON1) and high-density lipoprotein (HDL) in rheumatoid arthritis (RA).

DESIGN AND METHODS

We investigated the serum enzyme activity and concentration of PON1 and their relationship with serum lipids, high-density lipoprotein (HDL) parameters, and acute phase reactants of serum amyloid A (SAA) and C-reactive protein (CRP) in patients with RA.

RESULTS

Serum paraoxonase (PON) activity was significantly decreased in RA patients (n = 64, 131 +/- 53 micro mol/min/L) compared with healthy subjects (n = 155, 164 +/- 59) despite the absence of any difference in serum lipid levels between the two groups. This decrease of serum PON activity in RA patients was found in every genotype (Q/Q, Q/R, R/R) of PON1 at 192 Q/R. There was a different distribution in PON1 Q/R genotypes between RA patients and healthy subjects, and RA patients exhibited less (44%) positive PON1-Q than did the healthy subjects (66%). In a further investigation of age- and gender-matched subgroups of RA (n = 25) and healthy subjects (n = 25), not only serum PON activity, but also lecithin-cholesterol acyltransferase (LCAT) was found to be significantly decreased in RA patients (125 +/- 61 micro mol/min/L, 63.2 +/- 17.2 nmol/ml/hr/37 degrees C) than in healthy subjects (169 +/- 67, 74.7 +/- 19.5), respectively. PON1 and LCAT as well as HDL constituent apolipoprotein (apo) AI and apo AII, were altered significantly in RA patients.

CONCLUSIONS

Acute-phase HDL, which is remodeled structurally and functionally in RA, might be less anti-atherogenic due to the impairment of original HDL function. These alterations of HDL in RA patients may explain in part the reported increase in cardiovascular mortality in patients with RA.

Paraoxonase activity and paraoxonase 1 gene polymorphism in patients with uremia

Patients on hemodialysis (HD) show an increased risk for developing atherothrombotic events. The oxidative modification of low density lipoproteins (LDL) play an important role in the pathogenesis of atherosclerosis. In patients with uremia (chronic renal failure and HD), the increased oxidative stress induces oxidative modification of LDL. High density lipoproteins (HDL) exhibit a double antiatherogenic role, removing both lipid peroxides from LDL and cholesterol from tissues or vascular wall. Paraoxonase 1 (PON1) is one of three enzymes shown to prevent the formation of oxidized LDL. PON1 activity is modulated by its genetic polymorphism and by non-genetic factors, such as diet, smoking, acute phase reactants, and hormones. PON1 activity has been found to be significantly decreased in uremia. The present study aimed to verify the possibility that this reduced activity could be caused by a different PON1 gene polymorphism between patients on HD and healthy subjects, but this was not the case. The main cause may be identified in the different distribution of HDL subspecies, rather than in the different PON1 allele distribution between healthy subjects and patients with uremia.

Lipid changes in patients initiating efavirenz- and indinavir-based antiretroviral regimens

PURPOSE

To evaluate nonfasting lipid levels in a large cohort of patients on three HAART regimens: efavirenz + zidovudine + lamivudine (EFV+ZDV+3TC), efavirenz + indinavir (EFV+IDV), and indinavir + zidovudine + lamivudine (IDV+ZDV+3TC).

METHOD

Nonfasting lipid levels were analyzed from a large randomized multicenter treatment trial for HIV-infected patients initiating HAART. Treatment evaluations were carried out at prescribed intervals, and data were recorded and analyzed. Assessment was limited to high-density lipoprotein (HDL) and total cholesterol.

RESULTS

The results demonstrate an increase in the total cholesterol, ranging from 23 to 57 mg/dL, in the three combinations of HAART therapy. The increase was most significant in the EFV+IDV arm where the effects appear to be additive. HDL cholesterol also increased in all three arms, but the greatest increase was in the two groups containing EFV. In all three arms, the HDL cholesterol increased significantly in women while increases in men were seen only in the EFV-containing arms. Men taking either IDV-containing regimen had a greater increase in total cholesterol, and therefore the total/HDL cholesterol ratio rose significantly.

CONCLUSION

EFV and IDV independently elevate lipid levels. Alterations in the lipid levels may lead to increased cardiovascular risk in men, possibly mitigated by elevations in HDL cholesterol. In addition, changes in HDL cholesterol were significantly different between men and women.

Proinflammatory cytokines but not acute phase serum amyloid A or C-reactive protein, downregulate paraoxonase 1 (PON1) expression by HepG2 cells

The expression of paraoxonase1 (PON1) during inflammation has been investigated in vitro. The alteration of steady state PON1 mRNA in HepG2 cells by interleukin-1beta (IL-1beta) and tumor necrosis factor-alpha (TNF-alpha), was investigated relative to acute-phase serum amyloid A (A-SAA) mRNA. PON1 mRNA expression by HepG2 cells was decreased within three hours of stimulation by IL-1beta or TNF-alpha. Relative to PON1 mRNA expression, the pattern of steady state A-SAA mRNA expression was altered reciprocally and inversely by IL-1beta. These findings suggested that the decrease in serum PON activity after abdominal surgery in our previous clinical study may be ascribed to a decrease in steady state PON1 mRNA expression by liver with proinflammatory cytokines.

Serum amyloid A and high-density lipoprotein cholesterol: serum markers of inflammation in sarcoidosis and other systemic disorders

Hypocholesterolemia has been observed in several inflammatory diseases such as rheumatoid arthritis, myeloproliferative disorders, systemic lupus erythematosus and sarcoidosis. Serum amyloid A is an acute-phase reactant that is related to the high-density lipoprotein cholesterol. This review discusses the relationship between the activation of the cells of the monocyte-macrophage system, determined by the serum amyloid A levels, and the lipid metabolism, measured as alterations in plasma lipoprotein concentrations. The mechanisms of this association during acute inflammation are also discussed in this review.

Influence of serum amyloid A on the decrease of high density lipoprotein-cholesterol in active sarcoidosis

OBJECTIVE

We have previously observed low levels of high density lipoprotein (HDL) cholesterol in active sarcoidosis. The aim of this study was to analyze the role of serum amyloid A (SAA) on this lipid disorder.

METHODS

Eighty five untreated sarcoid patients, 40 with active disease and 45 with inactive disease, were recruited. Sarcoidosis activity was evaluated by means of clinical, chest X-ray, gallium-67 scan, serum angiotensin converting enzyme (peptidyl-dipeptidase A) values, and pulmonary function tests. Analysis of lipoprotein metabolism included: serum cholesterol, low density lipoprotein (LDL)-cholesterol, HDL-cholesterol, HDL(2)-cholesterol, HDL(3)-cholesterol, apolipoprotein A-I (apo A-I), apolipoprotein B (apo B), and triglyceride concentrations. Serum amyloid A protein and lecithin-cholesterol acyltransferase (LCAT) activity were measured.

RESULTS

In active sarcoidosis we found significantly reduced levels of HDL-cholesterol (1.17+/-0.36 vs. 1. 44+/-0.39 mmol/l, P=0.002), HDL(3)-cholesterol (0.78+/-0.23 vs. 1. 02+/-0.21 mmol/l, P<0.0001), and apo A-I (1.36+/-0.29 vs. 1.61+/-0. 27 g/l, P<0.0001) and significantly increased levels of triglyceride (1.51+/-0.64 vs. 1.03+/-0.46 mmol/l, P<0.0001), and apo B (1.14+/-0. 25 vs. 0.99+/-0.27 g/l, P=0.012) versus inactive sarcoidosis. Serum amyloid A concentrations were significantly increased in the patients with active disease (155.45+/-154.01 mg/ml) compared to the inactive sarcoid patients (89.70+/-65.36 mg/ml) (P=0.011). There were no significant differences in cholesterol, LDL-cholesterol, HDL(2)-cholesterol or LCAT values between groups. Multivariate logistic regression analysis showed that HDL-cholesterol (regression coefficient b=-1.96; S.E.=0.87; P=0.02) and SAA (regression coefficient b=0.01; S.E.=0.004; P=0.01) were the two variables independently associated with disease activity. Moreover, a significant negative correlation was observed between SAA levels and both HDL-cholesterol (r=-0.39; P=0.01) and apo A-I (r=-0.35; P=0.03) levels, in the active sarcoid group. Conversely, no correlation was found in the inactive sarcoid group.

CONCLUSION

The low HDL-cholesterol and apo A-I concentrations seen in active sarcoid patients are associated with a significant increase of SAA levels. We suggest that the displacement of apo A-I by SAA on HDL accounts for the lower level of HDL-cholesterol seen in active sarcoidosis.

Improvement in lipid and haemostasis patterns after Helicobacter pylori infection eradication in type 1 diabetic patients

Helicobacter pylori has been implicated in the cardiovascular risk of diabetic patients. The aim of our study was to investigate whether the Helicobacter pylori infection plays a role in the lipid and haemostasis patterns of type 1 diabetic patients. Twenty nine patients with type 1 diabetes mellitus and H. pylori infection were enrolled (Chlamydia pneumoniae negative). The H. pylori infection status was assessed by serology and urease breath test. In all patients levels of total cholesterol, triglyceride, HDL cholesterol, LDL cholesterol, lipoprotein (a) (Lpa) C reactive protein (CRP), fibrinogen, thrombin/antithrombin III complex (TAT), plasminogen activator inhibitor type 1(PAI-1), tissue plasminogen activator (t-PA) and von Willebrand antigen were measured. All patients were evaluated before and after H. pylori eradicating treatment with amoxicillin, clarithromycin and omeprazole. Twenty two patients were eradicated and seven remained infected. In H. pylori eradicated patients, HDL cholesterol increased (59.7+/-18.9 mg/dl vs 65.2+/-15. 9 mg/dl, P << 0.05), after treatment. After H. pylori eradication, the levels of CRP and TAT decreased (48+/-0.7 ng/l vs 3.3+/-0.4 ng/l;P << 0.05), (27.7+/-44.7 microg/ml vs 2.1+/-1.4 microg/ml, P << 0.05), respectively. The decrease in TAT was higher in the group of H. pylori (+) patients with higher levels of TAT (TAT >> 20 ng/ml, 92.8+/-41.6 ng/ml vs 1.9+/-2.0 ng/ml, P << 0.005; TAT 4Eth 20 ng/ml; 10.1+/-5.2 ng/ml vs 2.2+/-0.6 ng/ml, P << 0.05). These changes did not occur in patients without H. pylori eradication. Eradication of H. pylori infection in type 1 diabetic patients modifies some parameters of lipid and haemostasis patterns, (increase of HDL-cholesterol, reduction of Lpa and decrease of CRP and TAT) and so contributes to improvement of cardiovascular risk factors in these patients.

Ferritin correlates with C-reactive protein and acute phase serum amyloid A in synovial fluid, but not in serum

OBJECTIVE

To evaluate ferritin concentration in serum and synovial fluid (SF) as a marker of activity of arthritis in comparison with C-reactive protein (CRP) and acute-phase serum amyloid A protein (A-SAA).

METHODS

We determined the concentrations of ferritin, CRP and A-SAA in paired serum and SF in 34 rheumatoid arthritis (RA) and 21 osteoarthritis (OA) patients. The erythrocyte sedimentation rate (ESR) was also measured.

RESULTS

The serum concentrations of ferritin, CRP and A-SAA were 93 +/- 76 (mean +/- SD) ng/ml, 4 +/- 5 mg/ml, 8 +/- 4 mg/ml in OA and 140 +/- 227, 59 +/- 34, 289 +/- 223 in RA, respectively. There was no significant difference in serum ferritin levels between OA and RA, and serum ferritin did not correlate with ESR, CRP or A-SAA. Both serum CRP and A-SAA levels were significantly higher in RA than in OA (p < 0.0001, p < 0.0001), and correlated with ESR in all arthritis (r = 0.658, p < 0.0001, r = 0.404, p < 0.01), respectively. Serum CRP levels correlated with A-SAA levels in serum (r = 0.727, p < 0.0001). In SF, the concentrations of ferritin, CRP and A-SAA in RA (421 +/- 307, 25 +/- 20 and 39 +/- 41) were significantly higher (p < 0.01, p < 0.0001, p < 0.001) than those in OA (202 +/- 220, 2 +/- 2 and 2 +/- 2), respectively. There were significant correlations among SF ferritin, CRP and A-SAA.

CONCLUSION

Ferritin levels in SF but not in serum are significantly elevated in RA more than in OA, and ferritin correlated with CRP or A-SAA in SF, but not in serum. Higher levels of SF ferritin, as well as SF CRP and SF A-SAA, seem to reflect greater degrees of joints inflammation in RA and OA.

High-density lipoprotein: multipotent effects on cells of the vasculature

The epidemiological evidence showing a strong inverse correlation between the level of plasma high-density lipoprotein (HDL) and the incidence of heart disease suggests that HDL has a protective effect against cardiovascular disease. The mechanism of this protective effect has been the raison d'etre for much research. The ability of HDL to mediate cholesterol efflux from peripheral tissues has been used to explain the cardioprotective effect of HDL. However, there is little direct evidence to suggest that in subjects with low plasma levels of HDL the rate of cholesterol efflux from peripheral tissues is significantly reduced. This observation suggested that HDL may be mediating its protective effect through other mechanisms. This review provides an account of the burgeoning evidence that HDL has many effects on cellular processes, in addition to the effects on cholesterol efflux, and will illustrate the multipotency of this lipoprotein.

A longitudinal analysis of alteration in lecithin-cholesterol acyltransferase and paraoxonase activities following laparoscopic cholecystectomy relative to other parameters of HDL function and the acute phase response

The composition of high-density lipoprotein (HDL) changes during inflammation; however, potential changes of HDL function during inflammation and the effects of acute phase proteins that are either on the HDL particles or in the serum have not been clarified. The concentrations of C-reactive protein (CRP), serum amyloid A protein (apoSAA) isoforms, lipids and apolipoproteins, and the activities of lecithin-cholesterol acyltransferase (LCAT) and paraoxonase (PON) were measured before and after laparoscopic cholecystectomy, in 12 patients with cholecystolithiasis to clarify the function of acute-phase HDL and the relationship between acute-phase proteins and HDL functions. Both acute-phase apoSAA (A-apoSAA) and CRP increased, reached their maximum levels 3-6 days after the operation, and then returned to preoperative levels after 2 weeks. In contrast, apolipoproteins and LCAT decreased reciprocally, reached their minimum levels 3-6 days after the operation, and returned to preoperative levels after 2 weeks. However, PON decreased 3-6 days after the operation, and remained low even after 2 weeks. At the nadir the mean activities of LCAT and PON were 56 and 76% of the preoperative levels, respectively. HDL-cholesterol or constitutive apoSAA did not change significantly. LCAT has been reported to be involved in reverse-cholesterol transport and PON to be preventive for lipid peroxidation of low-density lipoprotein in vitro. Thus, during the acute phase of inflammation, HDL may be altered to an atherogenic state due to a decrease in LCAT and PON activities. Therefore, this longitudinal analysis was carried out to determine whether HDL function is modified in a single episode of inflammation and thus may contribute to the occurrence of atherosclerotic disease in patients with chronic or recurrent acute inflammation.

Analysis of changes in acute-phase plasma proteins in an acute inflammatory response and in rheumatoid arthritis using two-dimensional gel electrophoresis

Two-dimensional (2-D) gel analysis was used to examine differences in the levels of 19 plasma proteins: before and after an acute inflammatory reaction (parenteral typhoid vaccination) in normal subjects, between rheumatoid arthritis (RA) patients and normals and in RA patients treated with tenidap (120 mg) and piroxicam (20 mg). Typhoid vaccination increased levels of SAA, haptoglobin alpha1, haptoglobin alpha2, haptoglobin beta and alpha1-anti-chymotrypsin but decreased transthyretin and apolipoprotein E. In RA patients, serum amyloid A (SAA), haptoglobin alpha2, haptoglobin beta, alpha1-antichymotrypsin and C3 proactivator levels were elevated while apolipoprotein A-I, apolipoprotein A-IV, transthyretin, Gc-globulin, alpha2-HS glycoprotein, alpha2-macroglobulin and alpha1-B glycoprotein levels were decreased, compared to normals. Compared to piroxicam, tenidap lowered levels of alpha1-antiprotease and SAA but raised the levels of transthyretin, Gc-globulin, alpha2-HS-glycoprotein and alpha2-macroglobulin in RA patients. C-reactive protein (CRP) could not be quantified on 2-D gels but, when measured by rate nephelometry, levels were reduced after treatment with tenidap compared to piroxicam. The general pattern of the acute phase protein response to an acute inflammatory response to typhoid vaccination is similar to that in the chronic inflammatory condition, RA. The impact of tenidap on both positive and negative acute-phase proteins in RA patients could clearly be distinguished from that of piroxicam.

Low levels of high density lipoprotein cholesterol in patients with active sarcoidosis

OBJECTIVE

To determine lipoprotein abnormalities in patients diagnosed with sarcoidosis and their relation to disease activity.

METHODS

We studied 90 patients with biopsy-proven sarcoidosis who had not been treated with corticosteroids (44 with active disease and 46 with inactive disease) and 147 control subjects. Sarcoidosis activity was evaluated by means of clinical, chest X-ray, gallium-67 scan, serum angiotensin converting enzyme (peptidyl-dipeptidase A) values, and pulmonary function tests. Analysis of lipoprotein metabolism included: serum cholesterol, low density lipoprotein (LDL)-cholesterol, high density lipoprotein (HDL)-cholesterol, HDL2-cholesterol, HDL3-cholesterol, apolipoprotein A-I, apolipoprotein B, and triglyceride concentrations.

RESULTS

Patients with active sarcoidosis had significantly low HDL-cholesterol concentrations (1.15 +/- 0.27 mmol/l) as compared with inactive sarcoid patients (1.40 +/- 0.34 mmol/l) and with the healthy control subjects (1.49 +/- 0.34 mmol/l) (p = 0.00001). The decrease in the HDL-cholesterol concentrations seen in patients with active disease was due mainly to the cholesterol bound to HDL2 subfraction. Apolipoprotein A-I concentrations were significantly reduced in the patients with active disease (1.18 +/- 0.32 g/l) compared to the healthy controls (1.38 +/- 0.27 g/l) (p = 0.003). There were no significant differences in cholesterol, triglyceride, LDL-cholesterol or apolipoprotein B values among the three groups. Multivariate logistic regression analysis showed that HDL-cholesterol was the only variable independently associated with disease activity (Regression Coefficient b = -0.03; S.E. = 0.008; p = 0.0005).

CONCLUSION

The decrease in HDL-cholesterol that is observed in patients with sarcoidosis is limited to those with active disease.

Association between serum amyloid A proteins and coronary artery disease: evidence from two distinct arteriosclerotic processes

BACKGROUND

Serum amyloid A (SAA) proteins are a family of inflammatory apolipoproteins that may modify high-density lipoprotein structure and function. Elevations of SAA have been reported in unstable coronary syndromes, but the levels and types of SAA protein in humans with spontaneous or transplant-associated coronary artery disease are not known.

METHODS AND RESULTS

SAA levels were analyzed using an ELISA in 76 sera from 36 patients after cardiac transplantation and in 346 other individuals, 85 patients with atherosclerotic coronary disease plus 261 of their relatives. The mean SAA level was 5-fold higher in transplant patients (203+/-181 microg/mL [23 to 934 microg/mL]) compared with normal subjects without coronary disease (36+/-16 microg/mL [2.8 to 193 microg/mL], P<.005). The mean SAA level was significantly elevated in patients with transplant coronary disease (206+/-160 microg/mL, n=23) compared with those without (140+/-104 microg/mL, n=12, P=.02). Elevated SAA levels were associated with increased mortality after transplantation. On multiple regression analysis, SAA levels were predicted by corticosteroid dose, pretransplant diagnosis of atherosclerotic coronary artery disease, and the presence of transplant coronary disease. SAA levels were elevated in patients with spontaneous atherosclerotic coronary disease (49+/-31 microg/mL) compared with unaffected relatives (39+/-36 microg/mL, mean+/-SD, P=.02). There was no evidence for a genetic contribution to SAA levels. All inducible human SAA protein types were documented by immunoblotting in both spontaneous and transplant coronary disease.

CONCLUSIONS

Environmentally determined elevations in SAA levels in patients with both spontaneous and transplant coronary artery disease provide further evidence for a potential pathophysiological link between inflammation, lipoprotein metabolism, and the development of atherosclerosis.

Serum amyloid A and high density lipoprotein participate in the acute phase response of Kawasaki disease

In this study we report changes in HDL concentration and composition in acute and convalescent Kawasaki disease. Notable reductions in plasma HDL-cholesterol (0.54 +/- 0.2 mmol/L, normal level 0.7-1.81 mmol/L) and apolipoprotein A-I (apoA-I) (56 +/- 28 mg/dL, normal level 141 +/- 22 mg/dL) were observed in all 24 patients studied during the acute phase of Kawasaki disease. These changes were accompanied by the marked appearance of serum amyloid A (SAA) protein in the plasma, associated with HDL3-like lipoprotein particles. The distribution of apoA-I was analyzed in five patients and showed a significant increase in lipid-free apoA-I in the bottom fraction (28.8 +/- 4.1%, normal range 10-15%), suggesting displacement of apoA-I from the HDL particles by SAA. Within 2 wk after acute Kawasaki disease, levels of HDL-cholesterol and apoA-I returned to the normal range, and SAA disappeared from the plasma. The HDL of patients with Kawasaki disease was markedly enriched in triglyceride even in the absence of changes in total plasma triglyceride. The core composition of HDL returned to the normal range more slowly than the plasma HDL-cholesterol and apoA-I levels. This suggests that Kawasaki disease has a profound effect on the lipoprotein profile acutely and a more subtle sustained effect on the HDL composition. We interpret these changes as manifestations of the acute phase response in Kawasaki disease.

Changes in plasma levels of lipids and lipoprotein composition in patients with Kawasaki disease

Studies on the response of plasma lipids and lipoproteins to Kawasaki disease are scarce so far. The purpose of this study was to investigate the changes in plasma levels of lipids and apolipoproteins as well as the composition of different lipoproteins in patients during the acute and convalescence phases of Kawasaki disease. The results showed that during the acute phase, the concentrations of plasma high density lipoprotein (HDL)-cholesterol, apolipoprotein A-I (apoA-I) and A-II (apoA-II) were significantly reduced. While the reduction of HDL-cholesterol was mainly related to the lowering of esterified and unesterified cholesterols in HDL2 during the acute stage of Kawasaki disease, most of which recovered during the subsequent convalescence phase. The plasma concentration of triglycerides was 46% higher in patients during the acute phase of Kawasaki disease than in the control subjects, which may be ascribed to the increase of triglycerides in very low density lipoprotein (VLDL), low density lipoprotein (LDL) and HDL2. The variables studied above did not appear to be independent parameters. The level of plasma apoA-I showed a stronger negative association with triglyceride concentration (r = -0.22) than apoA-II (r = -0.11) and HDL-cholesterol (r = -0.07). Furthermore, the levels of cholesterol, apoA-I and apoA-II in HDL2, but not in HDL3, were inversely correlated with the levels of triglyceride. We conclude that the temporary changes of lipid levels associated with Kawasaki disease results predominantly from alterations of lipoprotein composition.

Serum amyloid A protein in patients with non-insulin-dependent diabetes mellitus

We determined the serum amyloid A protein (SAA) levels in patients with non-insulin-dependent diabetes mellitus (NIDDM), and investigated the possible association between SAA and the complications of NIDDM. The concentrations of SAA were measured in the plasma of 105 patients with NIDDM (52 men and 53 women, age mean +/- SD, 61 +/- 13 years) and 91 healthy subjects (37 men and 54 women, aged 57 +/- 11 years). SAA concentrations were assayed by enzyme-linked immunosorbent assay. SAA concentrations in the patients with NIDDM were significantly higher than those in healthy subjects (2.1 +/- 1.3 vs. 1.2 +/- 0.5 mg/L). There were no obvious relationships between SAA levels and duration of diabetes, type of therapy, or control of blood sugar in the patients with NIDDM. However, SAA levels in patients with NIDDM increased significantly, with increase of urinary albumin excretion (p = 0.027). The increase of SAA in the patients with NIDDM did not influence the serum concentrations of lipid or lipoprotein. The SAA concentration in NIDDM was unrelated to the type of treatment, but seemed to be related to the development of diabetic nephropathy.