Clinical Significance of Thrombospondin Type 1 Domain-Containing 7A and Neural Epidermal Growth Factor-Like 1 Protein in M-Type Phospholipase A2 Receptor-Negative Membranous Nephropathy / 中国医学科学院学报

Objective To investigate the clinical significance of thrombospondin type 1 domain-containing 7A (THSD7A) and neural epidermal growth factor-like 1 protein (NELL1) in phospholipase A2 receptor (PLA2R)-negative membranous nephropathy (MN). Methods A total of 116 PLA2R-negative MN patients treated in Hangzhou TCM Hospital Affiliated to Zhejiang Chinese Medical University from 2014 to 2021 were enrolled in this study.Immunohistochemistry was employed to detect THSD7A and NELL1 in the renal tissue.The pathological characteristics,treatment,and prognosis were compared between positive and negative groups. Results The 116 PLA2R-negative MN patients included 23 THSD7A-positive patients and 9 NELL1-positive patients.One patient was tested positive for both proteins.The THSD7A-positive group showed higher positive rate of IgG4 (P=0.010),more obvious glomerular basement membrane (GBM) thickening (P=0.034),and higher proportion of stage Ⅱ MN and lower proportion of stage I MN (P=0.002) than the THSD7A-negative group.The NELL1-positive group had lower positive rates of C1q and IgG2 (P=0.029,P=0.001),less obvious GBM thickening (P<0.001),more extensive inflammatory cell infiltration (P=0.033),lower proportion of deposits on multi-locations (P=0.001),and lower proportion of atypical MN (P=0.010) than the NELL1-negative group.One patient with THSD7A-positive MN was diagnosed with colon cancer,while none of the NELL1-positive patients had malignancy.Survival analysis suggested that THSD7A-positive MN had worse composite remission (either complete remission or partial remission) of nephrotic syndrome than the negative group (P=0.016),whereas NELL1-positive MN exhibited better composite remission of nephrotic syndrome than the negative group (P=0.015).The MN patients only positive for NELL1 showed better composite remission of nephrotic syndrome than the MN patients only positive for THSD7A (P<0.001). Conclusions THSD7A- and NELL1-positive MN is more likely to be primary MN,and there is no significant malignancy indication.However,it might have a predictive value for the prognosis of MN.

Pharmacogenetic testing improves treatment responses in patients with PLA2R-related membranous nephropathy / 南方医科大学学报

OBJECTIVE@#To evaluate the value of pharmacogenetic testing for improving the efficacy and safety of treatment with cyclosporine, tacrolimus, and cyclophosphamide (CTX) for PLA2R-related membranous nephropathy and for determing individualized and precise treatment plans for the patients.@*METHODS@#A total of 63 patients with PLA2R-related membranous nephropathy hospitalized in the Department of Nephrology at our hospital from January, 2019 to October, 2021 were enrolled in this study. Thirty-three of the patients underwent pharmacogenetic testing before taking the immunosuppressive drugs selected based on the results of genetic screening for sensitive targets, and the other 30 patients were empirically given immunosuppressive drugs according to the guidelines (control group). The clinical efficacy and adverse effects of the immunosuppressive drugs were analyzed for all the patients. The two groups of patients were compared for demographic and biochemical parameters including 24-h urine protein, serum albumin, renal function, and serum anti-phospholipase A2 receptor antibody both before and at 3 months after the beginning of the treatment.@*RESULTS@#Among the 33 patients undergoing pharmacogenetic testing, 51.5% showed a GG genotype for cyclosporine, and 61.6% had an AG genotype for tacrolimus; for CTX, 51.5% of the patients showed a homozygous deletion and 63.6% had an AA genotype. After treatment for 3 months, serum anti-phospholipase A2 receptor antibody, 24-h urine protein, and serum albumin levels were significantly improved in pharmacogenetic testing group as compared with the control group (P < 0.05).@*CONCLUSION@#Individualized and precise administration of immunosuppressive drugs based on pharmacogenetic testing better controls proteinuria and serum antiphospholipase A2 receptor antibodies and increases serum albumin level in patients with PLA2R-related membranous nephropathy.

A rare case of PLA2R- and THSD7A-positive idiopathic membranous nephropathy / Positividade tecidual dupla para PLA2R e THSD7A em nefropatia membranosa idiopática: raro relato de caso

ABSTRACT Idiopathic membranous nephropathy (IMN) is a frequent cause of nephrotic syndrome in adults. In terms of etiology, the condition may be categorized as primary/idiopathic or secondary. Literature on the pathophysiology of IMN has indicated the presence of autoantibodies (PLA2R and THSD7A) directed against podocyte antigens. The detection of antibodies against a domain favors IMN. The presence of autoantibodies against one of the domains would in theory exclude the possibility of there being autoantibodies against the other domain. However, cases of patients with PLA2R- and THSD7A-positive disease have been recently reported, showing that antibodies against two targets may be concomitantly produced via yet unknown pathophysiological mechanisms. This study reports the case of a 46-year-old male patient with nephrotic-range proteinuria, hematuria, hypoalbuminemia, and hypercholesterolemia submitted to biopsy and histopathology examination (LM, IF, IHC, and EM) eventually diagnosed with PLA2R- and THSD7A-positive IMN associated with IgA nephropathy, stressing our experience with the use of IgG subclasses, PLA2R, and THSD7A in the workup for MN and the relevance of adopting a broad and adequate approach to elucidating and acquiring knowledge of the pathophysiology of IMN.

RESUMO A Nefropatia Membranosa Idiopática (NMi) é uma frequente causa de síndrome nefrótica em adultos e sua etiologia pode ser estratificada em primária/idiopática ou secundária. O conhecimento da fisiopatologia da NMi sugeriu a presença de autoanticorpos (PLA2R e a THSD7A) direcionados contra antígenos existentes nos podócitos. A detecção de anticorpos contra um domínio favorece NMi. A presença de autoanticorpos contra um desses domínios autoexcluiria a possibilidade de autoanticorpos contra o outro domínio; no entanto, recentemente foram descritos casos que apresentaram dupla positividade para PLA2R e THSD7A, comprovando que, por mecanismos fisiopatológicos ainda não conhecidos, raramente pode existir produção concomitante de anticorpos contra os dois alvos. O presente estudo tem por objetivo relatar o caso de um paciente de 46 anos de idade, do sexo masculino, que apresentou quadro de proteinúria nefrótica, hematúria, hipoalbuminemia e hipercolesterolemia submetido a biópsia e exame histopatológico (ML, IF, IHQ e ME), confirmando um caso raro de NMi com positividade dupla para os anticorpos anti-PLA2R e anti-THSD7A e associação à nefropatia por IgA, mostrando nossa experiência com a utilização de subclasses de IgG, PLA2R e THSD7A na rotina laboratorial para a investigação da GNM e enfatizando a importância de uma abordagem ampla para adequada elucidação e conhecimento dos mecanismos fisiopatológicos na NMi.

Clinical significance of Mtype phospholipase A2 receptor and thrombospondin Type 1 domaincontaining 7A in primary membranous nephropathy / 中南大学学报(医学版)

OBJECTIVES@#To evaluate the value of thrombospond in Type I domain-containing 7A (THSD7A) and M-type phospholipase A2 receptor (PLA2R) in primary membranous nephropathy (PMN) and to explore the relationship between their antibody levels and prognosis.@*METHODS@#Renal tissues in 128 patients with membranous nephropathy in the Second Xiangya Hospital of Central South University were collected from February 2015 to August 2017, including 108 patients with primary membranous nephropathy (PMN group) and 20 patients with secondary membranous nephropathy (SMN) (SMN group). Indirect immunofluorescence method was used to detect the expression of PLA2R antigen in kidney tissues,and the glomerular expression of THSD7A antigen was examined by immunohistochemistry and indirect immunofluorescence. The serum levels of anti-PLA2R antibodies and THSD7A antibodies were also detected by ELISA. According to the results of PMN examination,the patients were also divided into a PLA2R-related membranous nephropathy group and a THSD7A-related membranous nephropathy group.@*RESULTS@#The positive rate of PLA2R in the renal tissues in the PMN group was higher than that in the SMN group (78% in the PMN group, 35% in the SMN group, <0.01),while the positive rate of anti-PLA2R antibody in the PMN group was also higher than that in the SMN group (50% in the PMN group, 25% in the SMN group, <0.05).The serum level of anti-PLA2R antibody was positively correlated with 24 h urine protein (=0.254, <0.05) and negatively correlated with serum albumin (=-0.236, <0.05). The expression of THSD7A was positive in glomeruli in 7 cases of the PMN group (6%) by immuno-histochemistry, and which was positive in 1case of the SMN group (5%).The serum levels of anti-THSD7A antibody in the PMN group were higher than those in the SMN group [(0.49±0.26) pg/mL in the PMN group,(0.34±0.27) pg/mL in the SMN group, <0.05]. There was no difference in the clinical characteristics between the PLA2R-related membranous nephropathy group and the THSD7A-related membranous nephropathy group.@*CONCLUSIONS@#PLA2R and THSD7A are the target antigen of PMN, and the associated autoantibodies are helpful for the differential diagnosis of PMN. The anti-PLA2R antibody levels can reflect the severity of the disease and evaluate the effect of treatment. The incidence of THSD7A membranous nephropathy is low, and monitoring the serum anti-THSD7A antibody levels can assess patients' condition and predict disease outcome.

Anti-phospholipase A2 receptor antibody as a prognostic marker in patients with primary membranous nephropathy

BACKGROUND: Phospholipase A2 receptor (PLA2R) has been identified as a major autoantigen in primary membranous nephropathy (MN). We evaluated the association between anti-PLA2R antibodies and clinical outcome in Korean patients with primary MN. METHODS: A total of 66 patients with biopsy-proven MN were included. Serum level of anti-PLA2R antibodies was measured by enzyme-linked immunosorbent assay. Biochemical parameters were estimated initially and at follow-up. RESULTS: Anti-PLA2R antibodies were detected in 52.1% and 27.8% of patients with primary and secondary MN, respectively. Forty-eight patients with primary MN were grouped based on presence or absence of anti-PLA2R antibodies. Proteinuria was more severe in anti-PLA2R-positive patients than in anti-PLA2R-negative patients (urine protein/creatinine ratio 7.922 ± 3.985 g/g vs. 4.318 ± 3.304 g/g, P = 0.001), and anti-PLA2R antibody level was positively correlated with proteinuria. The incidence of chronic kidney disease stage ≥ 3 was higher in anti-PLA2R-positive patients compared with anti-PLA2R-negative patients (P = 0.004). The probabilities of spontaneous remission were higher in anti-PLA2R-negative patients compared with anti-PLA2R-positive patients (P < 0.001). Multivariate analysis demonstrated that anti-PLA2R antibodies are an independent risk factor for developing chronic kidney disease stage ≥ 3 and for not reaching spontaneous remission. CONCLUSION: Detection of anti-PLA2R antibodies at diagnosis in patients with primary MN can predict prognosis and guide treatment decisions.

Biochemical characterization of a phospholipase A2 homologue from the venom of the social wasp Polybia occidentalis

Wasp venoms constitute a molecular reservoir of new pharmacological substances such as peptides and proteins, biological property holders, many of which are yet to be identified. Exploring these sources may lead to the discovery of molecules hitherto unknown. This study describes, for the first time in hymenopteran venoms, the identification of an enzymatically inactive phospholipase A2 (PLA2) from the venom of the social wasp Polybia occidentalis. Methods: P. occidentalis venom was fractioned by molecular exclusion and reverse phase chromatography. For the biochemical characterization of the protein, 1D and 2D SDS-PAGE were performed, along with phospholipase activity assays on synthetic substrates, MALDI-TOF mass spectrometry and sequencing by Edman degradation. Results: The protein, called PocTX, was isolated using two chromatographic steps. Based on the phospholipase activity assay, electrophoresis and mass spectrometry, the protein presented a high degree of purity, with a mass of 13,896. 47 Da and a basic pI. After sequencing by the Edman degradation method, it was found that the protein showed a high identity with snake venom PLA2 homologues. Conclusion: This is the first report of an enzymatically inactive PLA2 isolated from wasp venom, similar to snake PLA2 homologues.(AU)

Renal Phospholipase A2 Receptor and the Clinical Features of Idiopathic Membranous Nephropathy / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>According to the renal phospholipase A2 receptor (PLA2R) immunohistochemistry, idiopathic membranous nephropathy (iMN) could be categorized into PLA2R-associated and non-PLA2R-associated iMN. This study aimed to examine whether the non-PLA2R-associated iMN had any difference in clinical features compared with PLA2R-associated iMN.</p><p><b>METHODS</b>A total of 231 adult patients diagnosed as iMN were recruited to this retrospective study. Renal PLA2R expression was examined by immunofluorescence. Among these patients, 186 (80.5%) with complete baseline clinical data were used for further study. Urinary protein excretion, serum albumin, and creatinine were analyzed. For those patients with follow-up longer than 1 year, the relationship between PLA2R and response to immunosuppressants were analyzed. The t-test was used for parametric analysis and the Mann-Whitney U-test was used for nonparametric analysis. Categorical variables were described as frequencies or percentages, and the data were analyzed with Pearson's Chi-square test or Fisher's exact test.</p><p><b>RESULTS</b>Of the 231 iMN patients, 189 showed renal detectable PLA2R expression (81.8%). The baseline serum creatinine, serum albumin, and urine protein excretion were not significantly different between PLA2R-associated (n = 145) and non-PLA2R-associated iMN patients (n = 41). However, about 1/3 of the non-PLA2R-associated iMN had abnormal serological tests, significantly more common than PLA2R-associated iMN (31.7% vs. 8.3%, P = 0.000). The non-PLA2R-associated iMN had lower C4 levels compared with PLA2R-associated iMN (P = 0.004). The non-PLA2R-associated iMN patients also showed a better response to immunosuppressants (complete remission [CR] 42.9%; partial remission [PR] 14.3%) compared with PLA2R-associated iMN (CR 3.2%; PR 48.4%, P = 0.004) at the 3rd month.</p><p><b>CONCLUSIONS</b>There were no significant differences in serum creatinine, albumin, and urine protein excretion between PLA2R-associated and non-PLA2R-associated iMN, while the non-PLA2R-associated iMN patients showed more abnormal serological tests. The non-PLA2R-associated iMN seemed to respond more quickly to the immunosuppressive therapy compared with PLA2R-associated iMN.</p>

Role of M-type phospholipase A2 receptor and its antibody in hepatitis B virus-associated membranous nephropathy / 中南大学学报(医学版)

To examine levels of M-type phospholipase A2 receptor (PLA2R) and its antibody in the patients with hepatitis B virus-associated membranous nephropathy (HBV-MN), and to explore the correlation of PLA2R with laboratory parameters and pathological characteristics.
 Methods: A total of 49 adult patients with biopsy-proved HBV-MN were enrolled in this study. Levels of anti-PLA2R antibody in serum and PLA2R in renal tissue were detected. Patients were assigned into two groups: a positive PLA2R group and a negative PLA2R group. Differences in laboratory parameters and pathological characteristics were compared between the two groups.
 Results: Of 49 patients with HBV-MN, 17 had positive PLA2R expression in renal tissues. In the positive PLA2R group, 10 patients were positive for serum anti-PLA2R antibody. Patients with positive PLA2R expression in renal tissues showed higher levels of 24 hour urinary protein [(4.6±3.9) g/d], serum HbsAg (70.5%) and renal HbsAg expression (71%), while lower level of serum albumin [(24.1±7.5) g/L] than those of the negative group.
 Conclusion: PLA2R is expressed in the renal tissues and serum anti-PLA2R antibody can be detected in some HBV-MN patients. Positive PLA2R expression in renal tissue might be related to HbsAg deposition in serum and renal tissues. Patients with positive PLA2R expression in renal tissue have more severe glomerular sclerosis.

Detection of PLA2R1 in renal biopsy specimens of patients with idiopathic membranous nephropathy / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the prevalence of PLA2R1 in renal biopsy specimens of patients with idiopathic membranous nephropathy (IMN) and explore the relationship between PLA2R1 and IMN.</p><p><b>METHODS</b>A total of 108 adult patients with biopsy-proved glomerular diseases were enrolled in this study, including 41 with IMN, 2 with hepatitis B-associated membranous nephropathy, 8 with V lupus nephritis, 27 with IgA nephropathy, 19 with minimal change nephropathy, 5 with mild mesangial proliferative glomerulonephritis, and 6 with focal segmental glomeruloselerosis (FSGS). Indirect immunofluorescence assay was used to detect PLA2R1 in the biopsy specimens and the clinical variables of the IMN patients were analyzed.</p><p><b>RESULTS</b>In 35 of the 41 (85.37%) patients with IMN, PLA2R1 was detected with a fine granular pattern in the subepithelial deposits along the glomerular capillary loops. PLA2R1 antigen was not detected in patients with other glomerulopathies. No significant differences were found in age, serum creatinine, serum albumin, or 24-h urinary protein level between PLA2R1-positive and negative patients with IMN (P>0.05).</p><p><b>CONCLUSION</b>According to our results, 85.37% of adult patients with biopsy-proven IMN are positive for PLA2R1 antigen, which, however, does not contribute to variations of the patients' clinical manifestations.</p>

Application of Immunohistochemistry and Immunofluorescence Staining in Detection of Phospholipase A2 Receptor on Paraffin Section of Renal Biopsy Tissue / 中国医学科学院学报

<p><b>OBJECTIVE</b>To evaluate the application of immunohistochemistry and fluorescence staining method in the detection of phospholipase A2 receptor (PLA2R) on paraffin section of renal biopsy tissue,and to find an accurate and fast method for the detection of PLA2R in renal tissue.</p><p><b>METHODS</b>The PLA2R of 193 cases were detected by immunohistochemical staining,and the antigen was repaired by the method of high pressure cooker (HPC) hot repair plus trypsin repair. The 193 samples including 139 cases of idiopathic membranous nephropathy (IMN), 15 cases of membranous lupus nephritis, 8 cases of hepatitis B virus associated membranous nephropathy, 18 cases of IgA nephropathy, and 13 cases of minimal change diseases. To compare the dyeing effects, 22 paraffin sections of renal biopsy tissue of IMN cases with positive PLA2R were stained by using 4 different.</p><p><b>METHODS</b>of antigen repairing,which included HPC hot repair, HPC hot repair plus trypsin repair, water bath heat repair, and water bath heat repair plus trypsin repair. To compare the dyeing effects, 15 paraffin sections of renal biopsy tissue of IMN cases with positive PLA2R were stained by using 3 different.</p><p><b>METHODS</b>of antigen repairing,which included water bath heat repair plus trypsin repair, protease K digestion repair, and pepsin digestion repair.</p><p><b>RESULTS</b>In 193 cases, the positive rate of PLA2R in IMN cases was 90.6% (126/139), and the other 54 patients without IMN were negative. Twenty-two IMN patients were positive for PLA2R by using the HPC heat repair plus trypsin repaire or the water bath heat repair plus trypsin repair;while only a few cases of 22 IMN cases were positive by using the HPC hot repair alone or water bath heat repair alone. Fifteen IMN patients were positive for PLA2R by using water bath heat repair plus trypsin repair,protease K digestion repair,and pepsin digestion repair, but the distribution of positive deposits and the background were different.</p><p><b>CONCLUSIONS</b>PLA2R immunohistochemical staining can effectively identify IMN and secondary MN. For immunohistochemical staining and immunofluorescence staining, the preferred method of antigen repair is water bath heat repair plus trypsin repair.</p>

Progress on the M-type phospholipase A2 receptor in idiopathic membranous nephropathy / 中华医学杂志(英文版)

<p><b>OBJECTIVE</b>To highlight current knowledge about M-type phospholipase A2 receptor (PLA2R) which is the first human autoantigen discovered in adult idiopathic membranous nephropathy.</p><p><b>DATA SOURCES</b>Relevant articles published in English from 2000 to present were selected from PubMed. Searches were made using the terms "idiopathic membranous nephropathy, M-type PLA2R and podocyte."</p><p><b>STUDY SELECTION</b>Articles studying the role of M-type PLA2R in idiopathic membranous nephropathy were reviewed. Articles focusing on the discovery, detection and clinical observation of anti-PLA2R antibodies were selected.</p><p><b>RESULTS</b>M-type PLA2R is a member of the mannose receptor family of proteins, locating on normal human glomeruli as a transmembrane receptor. The anti-PLA2R in serum samples from MN were primarily IgG4 subclass. Technologies applied to detect anti-PLA2R autoantibody are mainly WB, IIFT, ELISA and so on. Studies from domestic and overseas have identified a strongly relationship between circulating anti-PLA2R levels and disease activity.</p><p><b>CONCLUSION</b>Recent discoveries corresponding to PLA2R facilitate a better understanding on IMN pathogenesis and may provide a new tool to its diagnosis, differential diagnosis, risk evaluation, response monitoring and patient-specific treatment.</p>

Association of single nucleotide polymorphism in M-type phospholipase A2 receptor gene with membranous nephropathy / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To assess the association between single nucleotide polymorphism in M-type phospholipase A2 receptor (PLA2R) gene and membranous nephropathy (MN) in a Chinese Han population.</p><p><b>METHODS</b>A total of 430 non-related Chinese Hans were enrolled, which included 145 patients with idiopathic membranous nephropathy (IMN), 53 patients with secondary MN and 232 normal controls (NC). The polymorphism of rs35771982 in PLA2R gene was determined with polymerase chain reaction-restriction fragment length polymorphism assay. Serum anti-PLA2R antibodies were detected by Western blotting.</p><p><b>RESULTS</b>The genotypic and allelic frequencies for rs35771982 was significantly different among the three groups (P=0.004; P<0.001). CC genotype and C allele were significantly more common in IMN group compared with NC group (P=0.002; P<0.001) or secondary MN group (P=0.011; P=0.001). In the IMN group, the CC genotype was correlated with serum albumin (Alb), 24-hour urine protein (24h UP) and positive rate of serum anti-PLA2R antibody (P<0.001, P<0.001, P=0.010), and was a risk factor for IMN (OR=8.927, 95%CI:2.107-37.821, P=0.003).</p><p><b>CONCLUSION</b>The CC genotype and C allele at rs35771982 in PLA2R gene are associated with susceptibility to IMN in Chinese Hans. The associations between CC genotype and severity of IMN as well as serum anti-PLA2R antibody have indicated that production of anti-PLA2R autoantibody in IMN patients is associated with mutation at the rs35771982 locus of PLA2R gene.</p>

Efficacy of tannins from Mimosa pudica and tannic acid in neutralizing cobra (Naja kaouthia) venom

In the present study, the effectiveness of Mimosa pudica tannins (MPT) in neutralizing the lethality of Naja kaouthia venom was compared with commercially derived tannins. Preincubation of MPT with N. kaouthia venom maintained 100 percent survival of mice after 24 hours. The mouse group in which there was no preincubation, no protection against the effects of the venom was observed. M. pudica tannin was found to be more effective in neutralizing the lethality of N. kaouthia venom when compared to commercial tannic acid. Two protein spots were missing in the two-dimensional gel electrophoresis (2-DE) of the MPT treated mouse indicating the down-regulation of venom proteins. The results from this study indicated that tannins obtained from M. pudica are better than tannic acid in neutralizing the lethality of N. kaouthia venom in vitro. However, further investigations are required to establish that M. pudica has potential for treating N. kaouthia snakebites.(AU)

Factores circulantes de injuria endotelial y procesos subendoteliales en mujeres postmenopáusicas sanas / Endothelial injuring factors and subendothelial events in healthy postmenopausal women

La concentración elevada de lipoproteínas aterogénicas con apo B en mujeres posmenopáusicas (MPM), es un componente importante del mecanismo multifactorial causante de la enfermedad coronaria. En MPM sanas (n=30) en comparación con premenopáusicas (MpreM) (n=28), se evaluó el perfil lipoproteico incluyendo apoproteínas A-I y B, LDL pequeña y densa, composición y oxidabilidad de LDL, proteína transportadora de colesterol esterificado y lipasa hepática. Se determinaron los siguientes factores emergentes: homocisteína, fosfolipasa A2, ferritina, PCR-hs (alta sensibilidad) y fibronectina proveniente de la matriz extracelular. La insulino-resistencia fue evaluada por la circunferencia de cintura, el índice HOMA y el índice triglicéridos/colesterol-HDL. El índice de riesgo apo B/apoA-I fue significativamente mayor en MPM (p<0,0001). MPM presentaron mayor proporción de LDL pequeña y densa, la cual correlacionó con el aumento de actividad de lipasa hepática (p<0,005), y con marcadores de insulino-resistencia (p<0,05). Fosfolipasa A2 (p<0,05), homocisteína (p<0,005), ferritina (p<0,0001), PCR-hs (p<0,005) y fibronectina (p<0,05)) fueron mayores en MPM. La oxidabilidad de LDL no mostró diferencias significativas pero correlacionó positivamente con LDL pequeña y densa (p<0,01), fosfolipasa A2 (p<0,05), homocisteína (p<0,05), PCR-hs (p<0,04), fibronectina (p<0,05) y cintura (p<0,02). Luego de ajustar por la condición menopáusica, edad y cintura, la oxidabilidad de LDL permaneció asociada con LDL pequeña y densa (b:0,36, p=0,027), homocisteína (b:0,36, p<0,038), fibronectina (b:0,41 p=0,05) y cintura (b:0,35, p=0,047). En este estudio, la interacción de factores de riesgo aterogénico clásicos y no tradicionales sugiere una secuencia de eventos que comienzan con la injuria endotelial causada por homocisteína y LDL pequeña y densa, que penetra en subendotelio donde su oxidación es favorecida por la homocisteína. Se produciría un proceso inflamatorio, que cursa con aumento de PCR y ferritina. La fosfolipasa A2, proveniente de macrófagos, atravesaría el endotelio unida a la LDL modificada, y promueve la liberación de fibronectina desde la matriz extracelular. La estrecha interacción entre la injuria endotelial, inflamación e insulino-resistencia se observaría desde estadíos subclínicos de aterosclerosis en MPM sanas.

In postmenopausal women (PMW), high concentrations of atherogenic apoB lipoproteins is an important component of the multifactorial mechanism underlying a higher risk of coronary artery disease, as compared with premenopausal women (PreMW). Lipoprotein pattern, including apopoproteins A-I and B, LDL chemical composition and small dense LDL (sdLDL), hepatic lipase activity, circulating cholesterol transfer protein and LDL oxidability were assessed in PMW (n=30) in comparison to PreMW (n=28). The following endothelial injuring factors were measured: homocysteine, lipoprotein binding phospholipase A2 (LpPLA2), ferritin, hs-CRP and fibronectin coming from extracellular vascular matrix. Insulin-resistance was evaluated by waist circumference, HOMA and triglyceride/HDL-cholesterol. PMW showed higher apoB/apoA-I (p<0.0001) and a higher proportion of sdLDL which showed significant correlations with the increase in hepatic lipase activity (p<0.005) and insulin-resistance markers (p<0.05). LpPLA2 (p<0.05), homocysteine (p<0.005), hs-CRP (p<0.005), fibronectin (p<0.05) and ferritin (p<0.0001) were elevated in PMW. LDL oxidability showed no differences between groups, but was positively correlated with waist (p<0.02), homocysteine (p<0.05), fibronectin (p<0.05), hs-CRP (p<0.04), LpPLA2 (p<0.05) and sdLDL (p<0.01). After adjusting by age, menopausal condition and waist, LDL oxidability remained associated with homocysteine (b: 0,36) p<0,038), sdLDL (b: 0.36, p=0.027), waist (b: 0.35, p=0.047) and fibronectin (b: 0,41 p=0.05). In this study, the interaction of classic and emerging atherogenic risk factors would suggest a sequence of events starting with endothelial damage caused by homocysteine and sdLDL, promoting its passage into the subendothelial space where it is oxidatively modified, enhanced by homocysteine. The above mentioned inflammatory process takes place with an increase in circulating hs-CRP and ferritin. LpPLA2, coming from macrophages, passes through the endothelium bound to modified LDL, promoting a release of fibronectin from the subendothelial extracellular matrix. Results suggest that the close interaction among endothelial injury, inflammation and insulin resistance can be observed since subclinical atherosclerosis states in healthy PMW.