Altered Expression of Complement Regulatory Proteins CD35, CD46, CD55, and CD59 on Leukocyte Subsets in Individuals Suffering From Coronary Artery Disease.

Studies conducted in animal models have suggested that membrane complement regulatory proteins play an important role in the pathophysiology of coronary artery disease (CAD). In this study, a total of 100 individuals, with stable CAD and 100 healthy controls, both groups predominantly male, were recruited. We evaluated the plasma levels of complement regulatory proteins (Cregs) CD35, CD46, CD55, and CD59 and their surface expression on granulocytes, lymphocytes, and monocytes by flow cytometry. The mRNA expression of these Cregs in total leukocytes was determined by quantitative PCR. The soluble forms of Cregs, C3c, Mannose binding protein-associated serine protease 2 (MASP-2), Platelet activating factor-acetyl hydrolase (PAF-AH), and inflammatory cytokines were quantified by ELISA. High plasma levels of C3c, indicative of complement activation, in addition to significantly low levels of Cregs, were observed in CAD patients. A significantly lower expression of CD46 and CD55 on the surface of lymphocytes, monocytes, and granulocytes and higher surface expression of CD35 and CD59 on granulocytes (p < 0.0001) was seen in CAD patients as compared to healthy donors. The high expression of CD59 on granulocytes positively correlated with the severity of disease and may serve as a potential marker of disease progression in CAD.

Pre-operative Hepatic Artery Resistive Index is a Non-invasive Predictive Indicator of Prognosis in Biliary Atresia.

AIMS: The aim of this study is to evaluate hepatic artery resistive index (HARI) as a noninvasive prognostic predictor by correlating it with peripheral blood nitric oxide (NO) levels, portal pressure (PP) and histopathological changes in the liver in patients of biliary atresia (BA). MATERIALS AND METHODS: Twenty-five patients were included in the study prospectively from November 2012 to June 2014. All patients underwent Doppler sonography to calculate the HARI preoperatively. Peripheral blood NO was also measured preoperatively. Biochemical liver function tests (LFTs) were measured preoperatively and at 1, 3, and 6 months postoperatively. The PP was measured intraoperatively, and a liver biopsy was taken in all patients. Disappearance of jaundice defined successful surgical treatment. Postoperatively, a hepatobiliary IminoDiacetic Acid scan (HIDA) was done to demonstrate a patent bilio-enteric pathway. RESULTS: The mean preoperative HARI was 0.78 ± 0.105, and the median was 0.80 (range 0.60-1.0). The median HARI was used to correlate the other parameters; 13 (52%) patients had HARI ≥0.8. The mean PP was 24.96 ± 6.54 mmHg. The HARI had a strong correlation with PP (P = 0.0001) and (NO) (P = 0.0001); with every 0.1 increase in HARI, there was 5.2 mmHg increase in PP and 3.8 µmol/L increase in NO. The histological parameters which reached significance in relation to HARI were hepatocellular damage, bile duct inflammation, portal inflammation, and portal fibrosis. The postoperative improvement in LFT was significantly better in patients with HARI <0.8. All four patients who died during or after the study period had HARI >0.8, elevated PP, and NO levels. CONCLUSIONS: Preoperative HARI was found to have a direct correlation with PP and peripheral blood NO as a measure of portal hypertension. A preoperative HARI ≥0.8 should be considered as a risk factor for poor outcomes in BA.

Portal pressure and blood nitric oxide levels as predictors of outcome in biliary atresia.

AIM: To evaluate the incidence of portal hypertension (PHT) in biliary atresia (BA) patients and to monitor its progress after Kasai portoenterostomy (KP) by measuring nitric oxide (NO) levels in peripheral blood. MATERIALS AND METHODS: A prospective cross-sectional study conducted over a period of 2 years. Intraoperative portal pressure (PP) and blood NO levels at presentation, 1-month, 3-month, and 6-month follow-up, were correlated with clinical and biochemical parameters in BA patients. The mean NO level in age-matched control group was 4.64 ± 2.32 µmol/L. RESULTS: Thirty-four BA patients underwent KP over a period of 2 years. The mean age of presentation was 2.7 months (range 1-4 months). The mean intraoperative PP was 21.3 ± 5.4 mmHg. The mean PP in patients aged <60 days, 61-90 days, and >90 days was 18.53 ± 4.45 mmHg, 20.33 ± 3.07 mmHg, and 26.5 ± 5.01 mmHg, respectively. The mean PP in the patients who underwent successful KP was 16.75 ± 3.54 mmHg while for those who continued to have jaundice it was 23.94 ± 4.63 mmHg (P < 0.001). NO levels closely followed the PP as shown by the regression equation NO = 4.79 + 0.64 PP mmHg, R (2) = 0.69. The mean NO level at presentation was 18.48 ± 4.17 µmol/L and at 1-month, 3-month, and 6-month follow-up was 11.94 ± 5.62 µmol/L, 10.79 ± 6.02 µmol/L, and 9.93 ± 6.53 µmol/L, respectively (P < 0.001). The difference in NO levels was also statistically significant between the patients who cleared jaundice and those with persisting jaundice. CONCLUSION: All BA patients had PHT at presentation. PHT worsens with age and has an adverse effect on outcome of KP. NO levels in blood closely follow PP and higher levels are associated with poor outcome.

Association of polymorphisms in angiotensin-converting enzyme gene with gestational diabetes mellitus in Indian women.

BACKGROUND: Numerous genes have been reported in relation with gestational diabetes mellitus (GDM), but the findings were not consistently replicated across populations, or there have been no detailed studies on them. Previous literatures suggested that, out of all angiotensin converting enzyme (ACE) gene polymorphisms, only ACE insertion/deletion (I/D) gene polymorphism has a strong association with GDM in Asian Indian women. AIM: This study was devoted to evaluate the association of four single nucleotide polymorphisms (SNPs) ACE A240T, C1237T, G2350A and I/D with GDM and Type 2 diabetes mellitus. MATERIALS AND METHODS: This study recruited 105 GDM cases, 119 Type 2 diabetes mellitus subjects and 120 controls. PCR-RFLP was used for identifying genotypes of ACE A240T, C1237T and G2350A and PCR was performed in the case of ACE I/D. RESULTS: Significant associations of ACE SNP's, C1237T, and G2350A with GDM were observed. Haplotype analysis revealed the remarkably significant evidence of association with SNP combination ACE A240T, C1237T, G2350A, and I/D with GDM patients (P = 0.024). Individuals possessing haplotype "TTAI" (frequency 30% in GDM and 0 in controls) derived from these SNPs had 185 fold increased risk of developing GDM (95% of confidence interval: 11.13-3102.15), which was highest when compared with other 15 haplotypes. CONCLUSION: Shorter-range haplotypes were also significant, but the only consistently associated alleles were found to be in ACE C1237T, G2350A, and I/D. These results suggested that the variant in close proximity to ACE C1237T, G2350A and/or I/D modulates susceptibility to GDM and noninsulin dependent diabetes mellitus in Indian women.

Modulation of PBMC-decay accelerating factor (PBMC-DAF) and cytokines in rheumatoid arthritis.

Studies have suggested that abnormal expression of complement regulatory proteins and cytokines contribute significantly to the path-physiology of rheumatoid arthritis. In this context, Decay accelerating factor (DAF) a complement regulatory protein is gaining increased attention. With the notion that immune effecter mechanisms are all interlinked and circulating peripheral blood mononuclear cells (PBMCs) should have a role in a systemic disease like rheumatoid arthritis, we studied the modulation and significance of PBMC-DAF and cytokines in RA. Seventy-five RA patients and 75 healthy controls were recruited. Expression of DAF and cytokines (IFN-γ, IL-17A and IL-10) in the PBMCs of patients and controls was determined. Correlations among DAF, cytokines, and disease activity were evaluated by standard statistical methods. The effect of IFN-γ, IL-17A, and IL-10 on the expression of DAF in patients and controls was studied in vitro. Expression of PBMC-DAF declined in patients both at mRNA and surface level and correlated negatively with the disease activity. Expression of IFN-γ also declined in patients but correlated positively with DAF and negatively with disease activity. Expression of IL-17A and IL-10 was higher in patients. The levels correlated positively with disease activity and negatively with DAF both in patients and controls. In vitro studies indicated that IFN-γ up-regulated DAF expression in PBMCs, whereas IL-17A and IL-10 had negative effect on the same. The decline in the PBMC-DAF is a contributing factor in manifestations of RA. Cytokine environment contributes to this decline. These findings brought novel insights into the complement-cytokine axis in the path-physiology of RA.

Complement and membrane-bound complement regulatory proteins as biomarkers and therapeutic targets for autoimmune inflammatory disorders, RA and SLE.

Complement system is a major effecter system of the innate immunity that bridges with adaptive immunity. The system consists of about 40 humoral and cell surface proteins that include zymogens, receptors and regulators. The zymogens get activated in a cascade fashion by antigen-antibody complex, antigen alone or by polymannans, respectively, by the classical, alternative and mannose binding lectin (MBL) pathways. The ongoing research on complement regulators and complement receptors suggest key role of these proteins in the initiation, regulation and effecter mechanisms of the innate and adaptive immunity. Although, the complement system provides the first line of defence against the invading pathogens, its aberrant uncontrolled activation causes extensive self tissue injury. A large number of humoral and cell surface complement regulatory protein keep the system well-regulated in healthy individuals. Complement profiling had brought important information on the pathophysiology of several infectious and chronic inflammatory disorders. In view of the diversity of the clinical disorders involving abnormal complement activity or regulation, which include both acute and chronic diseases that affect a wide range of organs, diverse yet specifically tailored therapeutic approaches may be needed to shift complement back into balance. This brief review discusses on the complement system, its functions and its importance as biomarkers and therapeutic targets for autoimmune diseases with focus on SLE and RA.

The incidence of portal hypertension in children with choledochal cyst and the correlation of nitric oxide levels in the peripheral blood with portal pressure and liver histology.

BACKGROUND AND AIMS: Symptomatic portal hypertension (PHT) as a complication of the choledochal cyst (CDC) is well-known, but the actual incidence of PHT in CDC has not been studied. This study was undertaken to evaluate the incidence of PHT in patients of CDC and correlate portal pressure (PP) with liver histology and blood nitric oxide (NO) levels. MATERIALS AND METHODS: In this cross-sectional study, PP was measured after surgical access but before any mobilization of the cyst by directly cannulating a tributary of portal vein (preoperative PP) and at completion of surgery before closure (postoperative PP). Blood sample for NO and liver function tests (LFTs) was taken before surgery and during subsequent follow-up at 1-month, 3 months, and 6 months. Liver histology was assessed under parenchymal, bile duct, and portal parameters. RESULTS: Measurement of PP and blood levels of NO was done in 20 patients. Mean preoperative PP was 16.45 ± 7.85 mmHg, and the median pressure was 14 mmHg (range 9-43). Mean of the postoperative PP was 14 ± 6.87 mmHg, and median pressure was 11.5 mmHg (range 7-37). The mean level of NO in the preoperative period was 11.85 ± 4.33 µmol/l, and median was 11.605 (range 5.24-22.77) µmol/l. NO levels at the first follow-up (1-month postoperative) were 5.96 ± 4.56 µmol/l and median value of 4.9 (range 1.74-23.56) µmol/l. Likewise, the mean and median values of NO at 3 months were 5.59 ± 7.15 µmol/l and median value of 3.71 (range 1.49-34.74) µmol/l. The mean and median levels of NO at 6 months postoperative were 5.08 ± 2.22 µmol/l and median of 4.59 (range 2.32-12.46) µmol/l. The fall in PP immediately after surgery was consistent and statistically significant (P = 0.001). There was statistically significant fall in the NO levels in the postoperative period as compared to the preoperative levels (P = 0.002). Bile duct proliferation was significantly correlated with PP (P = 0.05). Blood levels of NO closely followed the PP in the preoperative period and fell to baseline in subsequent follow-up. There was no statistically significant correlation between age at presentation, LFT and postoperative complications with either PP or NO levels. CONCLUSIONS: In this study, all patients with CDC had some degree of PHT. Measurement of PP and liver histology should be part of standard management protocol to take timely preventive measures so as to avoid life-threatening manifestations of PHT.

Evaluation of blood levels of nitric oxide as a means of differentiation between neonatal hepatitis and extrahepatic biliary atresia: A pilot study.

AIM: The differentiation between neonatal hepatitis (NH) and extrahepatic biliary atresia (EHBA) is not always possible despite all the currently available diagnostic modalities. In this study, an attempt has been made to evaluate the role of nitric oxide (NO) levels in the peripheral blood to differentiate between the two conditions, one requiring early surgical intervention (EHBA) and the other amenable to conservative medical management (NH). PATIENTS AND METHODS: Twenty patients who presented to the pediatric surgical service, over a 2 years period, with features of neonatal cholestasis were enrolled in the study. The diagnostic workup included documentation of history and clinical examination, biochemical liver function tests, ultrasonography, hepatobiliary scintigraphy (HS), and magnetic resonance cholangio-pancreaticography (MRCP). These patients did not show excretion on HS and intrahepatic ducts on MRCP. Hence, they were subjected to mini-laparotomy and operative cholangiography (OC). The EHBA patients were treated with the Kasai's portoenterostomy procedure, and the extrahepatic ducts were flushed with normal saline in NH patients. All patients were evaluated preoperatively for levels of NO in the peripheral blood by the Greiss reaction spectrophotometrically at 540 nm. Normal values were determined from a cohort of controls. The median (range) levels of NO in patients with EHBA and NH were compared, and the statistical significance of the difference was calculated by applying the Wilcox Rank Sum test. A P = 0.05 was considered as significant. RESULTS: Of the 20 patients enrolled in the study, 17 patients were treated for EHBA (Group I) and the remaining 3 patients had patent ducts on OC and were thus diagnosed as NH (Group II). The mean age of the patients in Groups I and II was comparable: 2.79 ± 0.75 and 2.67 ± 0.58 months, respectively (P = 0.866). The median NO levels were significantly elevated in each of the two groups as compared to the controls (5.6 µmol/l, range 1.26-11.34 µmol/l); when compared among themselves, the NO levels were significantly higher in Group I, 64.05 µmol/l (range 24.11-89.43 µmol/l), when compared with Group II, 41.72 µmol/l (range 23.53-45.63 µmol/l) (P = 0.022). CONCLUSION: The serum levels of NO were found to be significantly higher in patients with EHBA as compared to those with NH. Hence, this may be a useful biochemical marker for the preoperative differentiation of EHBA from NH. However, a larger study is required for establishing the validity of the statistical significance.

Membrane-bound complement regulatory proteins as biomarkers and potential therapeutic targets for SLE.

For the last two decades, there had been remarkable advancement in understanding the role of complement regulatory proteins in autoimmune disorders and importance of complement inhibitors as therapeutics. Systemic lupus erythematosus is a prototype of systemic autoimmune disorders. The disease, though rare, is potentially fatal and afflicts women at their reproductive age. It is a complex disease with multiorgan involvement, and each patient presents with a different set of symptoms. The diagnosis is often difficult and is based on the diagnostic criteria set by the American Rheumatology Association. Presence of antinuclear antibodies and more specifically antidouble-stranded DNA indicates SLE. Since the disease is multifactorial and its phenotypes are highly heterogeneous, there is a need to identify multiple noninvasive biomarkers for SLE. Lack of validated biomarkers for SLE disease activity or response to treatment is a barrier to the efficient management of the disease, drug discovery, as well as development of new therapeutics. Recent studies with gene knockout mice have suggested that membrane-bound complement regulatory proteins (CRPs) may critically determine the sensitivity of host tissues to complement injury in autoimmune and inflammatory disorders. Case-controlled and followup studies carried out in our laboratory suggest an intimate relation between the level of DAF, MCP, CR1, and CD59 transcripts and the disease activity in SLE. Based on comparative evaluation of our data on these four membrane-bound complement regulatory proteins, we envisaged CR1 and MCP transcripts as putative noninvasive disease activity markers and the respective proteins as therapeutic targets for SLE. Following is a brief appraisal on membrane-bound complement regulatory proteins DAF, MCP, CR1, and CD59 as biomarkers and therapeutic targets for SLE.

Two- and three-locus haplotypes of the paraoxonase (PON1) gene are associated with coronary artery disease in Asian Indians.

INTRODUCTION: In view of the reported association of SNPs in the paraoxonase (PON1) gene with coronary artery disease (CAD), and the absence of conclusive data from India, we investigated the relationship of three SNPs at different loci (-108C/T, L55M and Q192R) of the PON1 gene and their haplotypes with CAD among people residing in the northern plains of India. MATERIALS AND METHODS: One hundred and seventy-eight healthy controls and two hundred and four angiographically-proven CAD patients were genotyped using PCR-RFLP. RESULTS: Of the three SNPs, only the R allele of Q192R polymorphism was associated with CAD (p<0.05). Two locus haplotypes QT (OR 0.55, p=0.0004, 95% CI 0.39-0.77, significant) and LQ (odds ratio 0.73, p=0.03, 95% CI 0.55-0.97, trend) showed protective effects, while haplotypes MR (OR=5.36, p=0.0001, 95% CI 2.045-14.049) and MC (OR=2.71, p=0.011, 95% CI 1.221-6.046) were associated with increased risk of CAD. MRT, a minor three-locus haplotype also displayed significant association (OR 4.93, 95% CI 1.7-13.5) with the disease. Significance was assessed after applying Bonferroni's correction. CONCLUSIONS: Our study revealed that only one SNP at a single locus but several haplotype combinations of PON1 coding and promoter-region polymorphisms were associated with the risk of or protection against CAD. Thus, haplotype analysis brought better insights into the association of PON1 gene polymorphisms with CAD in Asian Indians.

Frequency distribution of the single-nucleotide -108C/T polymorphism at the promoter region of the PON1 gene in Asian Indians and its relationship with coronary artery disease.

A single-nucleotide promoter region polymorphism (-108C/T) of the paraoxonase (PON1) gene had been suggested to influence an individual's susceptibility to coronary artery disease (CAD). No data is available on this polymorphism from India. One hundred seventy-eight healthy individuals and 204 angiographically proven CAD patients were recruited to get baseline data on the frequency distribution of the -108C/T polymorphism in normal people of Asian Indian ethnicity and its relation with the risk of CAD. Polymerase chain reaction followed by restriction fragment length analysis was used as the method for genotyping. Blood samples were used for DNA isolation. In the normal subjects, the genotypes were distributed as CT (43.26%) > CC (30.34%), >TT (26.4%). The allele frequency of the C allele was 0.52, and that of the T allele was 0.48. The patients showed a similar pattern, but the TT genotype was about two times more frequent in the controls than in patients. Odds ratios for developing CAD for individuals with CT, TT, and CT + TT genotypes were 0.89 (0.50-1.59), 0.56 (0.27-1.08), and 0.76 (0.44-1.29), respectively (at 95% confidence interval), when compared to CC homozygous people (age- and sex-adjusted, p = 0.114, all genotypes compared). This suggested a trend for the T allele as protective against CAD. This first report on the frequency distribution of the -108C/T polymorphism in people of Asian Indian ethnicity suggests that the normal distribution is similar to that observed for the Chinese, Japanese, and Latino people, but the disease association is unique. The TT genotype and the T allele which are widely found associated with the risk of CAD showed a protective trend in this study.

Immunomodulation of serum complement (C3) and macrophages by synthetic pyrethroid fenvalerate: in vitro study.

Fenvalerate, a type II synthetic pyrethroid, has emerged as one of the most potent indoor toxicants. Despite its widespread usage, the adverse effect of this insecticide on immune defense mechanism has not been comprehensively investigated. In this in vitro study we report the effect of fenvalerate on two pivotal components of the immune network, namely the complement system and macrophages. Fenvalerate treated human sera showed serum complement activation as evident by significant (p<0.05) increase in C3b, C3d and C3a levels and a significant (p<0.05) decline in CH50 levels. Further detailed study demonstrates that the activation of complement system is through alternative pathway. This is possibly responsible for various allergic manifestations often reported in subjects exposed to fenvalerate. In addition, fenvalerate induce cellular apoptosis and cytotoxicity, as demonstrated by cytoplasmic vacuolization, heterochromatin condensation, hypodiploid nuclei and DNA fragmentation in macrophages. Considerable deleterious effects on macrophages in conjunction with uncontrolled serum complement activation are probably one of the major mechanisms contributing for the immunosuppressive effects of fenvalerate.

Complement Receptor 1: disease associations and therapeutic implications.

Exaggerated complement activation is a key event in the pathogenesis of a range of autoimmune and inflammatory diseases. Complement Receptor 1 (CR1) has emerged as a molecule of immense interest in gaining insight to the susceptibility, pathophysiology, diagnosis, prognosis and therapy of such diseases. This review brings forth a composite view of the current understanding on the structure, functions, genetics, disease associations and therapeutic implications of CR1.

Immunomodulatory effect of DDT (bis[4-chlorophenyl]-1,1,1-trichloroethane) on complement system and macrophages.

DDT (bis[4-chlorophenyl]-1,1,1-trichloroethane) is responsible for many immuno-dysregulatory functions in exposed animals, but data particularly on complement system and macrophages are limited. In this study we have shown that DDT activates the complement system through the alternative pathway in the absence of any pathogen. A significant (p<0.05) increase in C3b, C3d and C3a generation, and decline in complement hemolytic activity was observed in insecticide exposed sera. The uncontrolled complement consumption reduces the lytic activity of the complement, which enhances the susceptibility to pyogenic infection if the exposure to DDT remains unabated. Further, DDT induced the significant (p<0.05) production of tumor necrosis factor-alpha (TNF-alpha) and nitric oxide (NO) in macrophages and thus contributes inflammatory reactions, cytokine imbalance and immune-dysregulation. These molecular changes in macrophages lead to structural aberrations like heterochromatin condensation, loss of pseudopodia, cytoplasmic vacuolization, DNA fragmentation and hypodiploid nuclei as seen in our study, suggesting apoptosis. However, in presence lipopolysaccharide, DDT induced significant (p<0.05) suppression of TNF-alpha and NO generation, suggestive of impairment of macrophage microbiocidal effects. This study concludes that the functional and structural derangements of macrophages in association with uncontrolled and excessive complement consumption by DDT are perhaps one of the major mechanisms contributing to the immunosuppressive effects of insecticide.

Association of eNOS Glu298Asp gene polymorphism with essential hypertension in Asian Indians.

BACKGROUND: Several reports suggested association between the T allele of the endothelial nitric oxide synthase gene polymorphism (eNOS) Glu298Asp (G --> T at nucleotide 894, exon 7) with essential hypertension (EHT). Findings, however are not uniform. In this case-control study, we determined the prevalence and distribution of the above polymorphism and their relationship with the disease to elucidate the association of this polymorphism with the risk and pathophysiology of EHT in the Asian Indians and significance of T allele in this context. METHODS: Two hundred normal controls and 226 patients with EHT from Delhi and surrounding areas were recruited for the investigation. Venous blood samples were used for genotyping. Genotyping was done by PCR-RFLP. RESULTS: The data suggested higher prevalence of GT+TT genotypes in patients as compared to the controls and association of T allele with EHT [p<0.001, odds ratio at 95% CI, 2.10 (1.34-3.28)]. CONCLUSIONS: Asian Indians of this region with T allele may be at higher risk of EHT.

Modulation of CR1 transcript in systemic lupus erythematosus (SLE) by IFN-gamma and immune complex.

Reduced expression of Erythrocyte Complement Receptor 1 (E-CR1) is envisaged to contribute significantly to the pathophysiology of systemic lupus erythematosus (SLE). We determined the levels of CR1 transcript in the neutrophils from 25 untreated patients with active SLE and 25 normal healthy individuals and, studied the effect of interferon-gamma (IFN-gamma), interleukin-4 (IL-4) and immune complexes (IC) on the same. The study revealed a marked decline in the levels of neutrophil CR1 (N-CR1) transcript in the patients with SLE, and differential pattern of IFN-gamma and IL-4 expression in the neutrophils from normals and patients. Opsonized immune complexes down regulated CR1 transcript in patients and IFN-gamma up regulated the same both in normals and patients. Immune complexes suppressed this effect of IFN-gamma. IL-4 also suppressed the effect of IFN-gamma but effect confined only to the normals. This is the first real-time RT-PCR data comparing the neutrophil CR1 expression in normals and patients with SLE and its modulation by IFN-gamma, IL-4 and immune complexes. IFN-gamma and immune complexes, respectively, emerged as the positive and negative modulators of neutrophil CR1 transcript in SLE.

Low levels of plasma soluble complement receptor type 1 in patients receiving thrombolytic therapy for acute myocardial infarction.

BACKGROUND: Administration of recombinant soluble CR1 (sCR1) has been shown to attenuate complement mediated myocardial injury in animal models of acute MI. The plasma level of sCR1 in humans with acute MI is not known. We determined the levels of the complement regulatory protein, complement receptor type-1 (CR1) in plasma and its expression on the surface of leukocytes of patients receiving thrombolysis for acute myocardial infarction (AMI). METHODS: Plasma sCR1 was measured by a sandwich ELISA. The levels in patients with AMI were compared with those in normal controls. Leukocyte surface expression of CR1 was measured by flow cytometry. We correlated these parameters with clinical outcome and left ventricular ejection fraction. RESULTS: Patients had very low plasma sCR1 levels. Mean plasma sCR1 levels were significantly less than in controls (6 +/- 3.6 ng/mL vs. 44.6 +/- 12.2 ng/mL, P < 0.00001). Patients who had an adverse in-hospital outcome had significantly lower sCR1 levels when compared to those who had an uneventful course (3.8 +/- 2.0 ng/mL and 7.1 +/- 3.8 ng/mL respectively, P = 0.01). The low plasma sCR1 was despite significantly greater lymphocyte and monocyte surface CR1 (which is a potential source of plasma sCR1). CONCLUSION: Plasma sCR1 levels are reduced in patients receiving thrombolysis for AMI. Replenishing plasma sCR1 might limit complement-mediated injury in this setting.

Role of ascorbic acid on in vitro oxidation of low-density lipoprotein derived from hypercholesterolemic patients.

BACKGROUND: The susceptibility of low-density lipoprotein (LDL) to oxidation is thought to be a crucial factor responsible for atherogenesis. There is substantial evidence for a role of dietary antioxidants in the prevention of atherogenesis and the protective effect of antioxidant nutrients may be mediated through inhibition of the oxidative modification of LDL. METHODS: We performed in vitro oxidation of LDL derived from normal and hypercholesterolemic individuals in absence and presence of different doses of ascorbic acid. RESULTS: The serum lipid peroxidation level was significantly increased in hypercholesterolemic patients and their LDL has shown a greater propensity towards in vitro oxidation. Hypercholesterolemic LDL required a higher amount of ascorbic acid to reduce its oxidation level as compared to LDL isolated from normocholesterolemic individuals. CONCLUSION: This observation may be of importance in designing future studies of antioxidant supplementation in patients with hypercholesterolemia which is one of the major risk factors for atherosclerosis.

Prevalence of eNOS Glu298Asp polymorphism in healthy volunteers from a region of Northern India.

OBJECTIVE: Endothelial nitric oxide synthase (eNOS) Glu298Asp polymorphisms are under extensive study worldwide due to their suggested role in cardiovascular disorders. This polymorphism had gained more attention since several reports suggest its association with hypertension and coronary artery disease (CAD). Asian Indians are highly susceptible to ischemic heart dis eases. We determined the prevalence of eNOS Glu298 Asp polymorphism in 139 healthy volunteers from Delhi and the surrounding areas. The subjects were recruited from those who willingly participated in this study in response to a publicized call and a standard questionnaire. Male to female ratio was 2.7:1 due to the larger number of male participants in this investigation. This, however, does not represent normal male to female distribution in the area. Despite the male bias, this investigation was justified. The prevalence of CAD in males is about 3 times higher in this region and no data had so far been available on the distribution of this polymorphism from India. METHOD: The eNOS Glu298Asp polymorphism was studied by PCR-RFLP. RESULTS: Distribution of genotype GG, GT and TT in the study subjects was found to be 71.22, 28.06 and 0.72%, respectively, and allele frequency was G,0.853;T,0.147. CONCLUSION: T allele had been described as susceptibility allele for CAD in several population studies. The frequency of the T allele was found to be two times higher in our subjects than that reported for Japanese and Korean populations. This study does not provide any direct evidence for eNOS gene disease associations but is the first report on the prevalence of eNOS Glu298Asp gene polymorphism in Indian subjects. Whether the observed pattern of eNOS Glu298Asp polymorphism contributes to the greater susceptibility of Asian Indians to CAD as compared to the other population groups, needs to be investigated.

Association of leukocyte CR1 gene transcription with the disease severity and renal involvement in systemic lupus erythematosus.

The reduced level of complement receptor 1 (CR1) on erythrocytes is speculated as a key mechanism contributing to immune complex (IC) overload and exaggerated complement (C) activation in systemic lupus erythematosus (SLE). Comparatively, fewer studies documented lower levels of CR1 on leukocytes and glomerular podocytes in this disease. The decline in E-CR1 is largely believed as an acquired phenomenon caused due to the proteolytic cleavage of CR1 from erythrocyte membrane. The mechanism underlying reduced CR1 expression on nucleated cells is under constant investigation. Recently, reduced leukocytes CR1 gene transcription had been demonstrated in SLE and was suggested as the main cause of decline in leukocyte CR1 (L-CR1). The relationship of L-CR1 gene transcription with severity and pathophysiology of disease needs to be elucidated. We determined the levels of L-CR1 in 30 active SLE patients and compared with normal healthy controls (n = 30). Patients were categorized into two groups i.e., with nephritis (n = 14) or without nephritis (n = 16). The expression of L-CR1 at transcriptional level was correlated with the levels of serum CIC, C3 and anti dsDNA antibodies. The levels of L-CR1 transcription were significantly reduced in all SLE patients as compared to controls (P < 0.001). This decline in L-CR1 however, was more marked in patients with nephritis than those without nephritis. In addition, the serum levels of CIC, anti dsDNA antibodies were higher and the levels of serum C3 were lower than the normal range in the patients. The difference was much more marked in SLE patients with nephritis than those without nephritis. The levels of L-CR1 transcription correlated negatively with the levels of CIC and anti dsDNA antibodies and positively with serum C3 levels. Thus, between SLE patients with and without nephritis, we found significant difference in the levels of L-CR1 transcription (P < 0.01), CIC (P < 0.05), anti dsDNA antibodies (P < 0.01) and C3 (P < 0.01). Our findings suggest that L-CR1 is drastically reduced in patients with severe form of SLE, i.e., lupus nephritis. Determination of L-CR1 expression at transcriptional level in addition to disease hallmarks like C3, CIC and anti-dsDNA antibodies may facilitate the assessment of severity of SLE and discrimination between patients with or without renal involvement.