Association of serum prolidase activity in patients with isolated coronary artery ectasia

Next-generation sequencing of prolidase gene identifies novel and common variants associated with low prolidase in coronary artery ectasia

BACKGROUND

Decreased collagen biosynthesis and increased collagenolysis can cause ectasia progression in the arterial walls. Prolidase is a key enzyme in collagen synthesis; a decrease in prolidase activity or level may decrease collagen biosynthesis, which may contribute to ectasia formation. Considering that, the variations in PEPD gene encoding prolidase enzyme were evaluated by analyzing next-generation sequencing (NGS) for the first time together with known risk factors in coronary artery ectasia (CAE) patients.

METHODS

Molecular analysis of the PEPD gene was performed on genomic DNA by NGS in 76 CAE patients and 76 controls. The serum levels of prolidase were measured by the sandwich-ELISA technique.

RESULTS

Serum prolidase levels were significantly lower in CAE group compared to control group, and it was significantly lower in males than females in both groups (p < 0.001). On the other hand, elevated prolidase levels were observed in CAE patients in the presence of diabetes (p < 0.001), hypertension (p < 0.05) and hyperlipidemia (p < 0.05). Logistic regression analysis demonstrated that the low prolidase level (p < 0.001), hypertension (p < 0.02) and hyperlipidemia (p < 0.012) were significantly associated with increased CAE risk. We identified four missense mutations in the PEPD gene, namely G296S, T266A, P365L and S134C (novel) that could be associated with CAE. The pathogenicity of these mutations was predicted to be "damaging" for G296S, S134C and P365L, but "benign" for T266A. We also identified a novel 5'UTR variation (Chr19:34012748 G>A) in one patient who had a low prolidase level. In addition, rs17570 and rs1061338 common variations of the PEPD gene were associated with low prolidase levels in CAE patients, while rs17569 variation was associated with high prolidase levels in both CAE and controls (p < 0.05).

CONCLUSIONS

Our findings indicate that the low serum prolidase levels observed in CAE patients is significantly associated with PEPD gene variations. It was concluded that low serum prolidase level and associated PEPD mutations may be potential biomarkers for the diagnosis of CAE.

Hypertension and coronary artery ectasia: a systematic review and meta-analysis study

BACKGROUND

Coronary artery ectasia (CAE) is characterized by the enlargement of a coronary artery to 1.5 times or more than other non-ectasia parts of the vessel. It is important to investigate the association of different factors and CAE because there are controversial results between available studies. We perform this systematic review and meta-analysis to evaluate the effects of hypertension (HTN) on CAE.

METHODS

To find the potentially relevant records, the electronic databases, including Scopus, PubMed, and Science Direct were searched on 25 July 2019 by two of the authors independently. In the present study, the pooled odds ratio (OR) accompanied by 95 % confidence intervals (CIs) were calculated by a random-effects model. Heterogeneity presented with the I² index. Subgroup analysis and sensitivity analysis by the Jackknife approach was performed.

RESULTS

Forty studies with 3,263 cases and 7,784 controls that investigated the association between HTN and CAE were included. The pooled unadjusted OR of CAE in subjects with HTN in comparison by subjects without HTN was estimated 1.44 (95 % CI, 1.24 to 1.68) with moderate heterogeneity (I² = 41 %, Cochran's Q P = 0.004). There was no evidence of publication bias in the analysis of HTN and CAE with Egger's test (P = 0.171), Begg's test (P = 0.179). Nine articles reported the adjusted effect of HTN on CAE by 624 cases and 628 controls. The findings indicated the overall adjusted OR was 1.03 (95 % CI, 0.80 to 1.25) with high heterogeneity (I² = 58.5 %, Cochran's Q P = 0.013).

CONCLUSIONS

We found that when the vessel was in normal condition, HTN was not very effective in increasing the chance of CAE and only increased the CAE chance by 3 %. This is an important issue and a warning to people who have multiple risk factors together. More studies need to be performed to further establish these associations by reported adjusted effects.

Association of C-Reactive Protein to Albumin Ratio in Patients with Isolated Coronary Artery Ectasia

Fundamento

A ectasia da artéria coronária (EAC) é definida como a dilatação difusa ou localizada do lúmen da artéria coronária com diâmetro de 1,5 a 2,0 vezes o diâmetro da artéria coronária normal adjacente. A relação proteína C-reativa/albumina (CAR, sigla em inglês) é um marcador inflamatório útil que tem sido documentado em doença arterial coronariana.

Objetivo

Analisar a associação entre a EAC e a CAR.

Métodos

Um protocolo caso-controle foi utilizado neste estudo. Foram incluídos 102 pacientesconsecutivos com EAC isolada sem estenose (56 homens e 46 mulheres; idade média de 60,4 ± 8,8 anos). O grupo controle era constituido pelo mesmo número de pacientes pareados por sexo e idade com artérias coronárias normais (55 homens e 47 mulheres; idade média de 61,2 ± 9,1 anos). Características clínicas, achados laboratoriais e histórico de uso de medicamentos foram registrados. Foram realizados teste t de Student, teste U de Mann-Whitney, teste do qui-quadrado, análise de regressão linear e logística. Foi considerado estatisticamente significativo p bilateral < 0,05.

Resultados

A CAR estava aumentada nos pacientes com EAC em comparação com os controles (32 e 16; p < 0,001). Além disso, foi verificado que a CAR era um preditor independente da EAC (razão de chances = 2,202; intervalo de confiança 95%, 1,184 – 5,365; p < 0,001).

Conclusão

No presente estudo, determinamos que os níveis da CAR estavam significativamente mais altos no grupo EAC que no grupo controle e a CAR estava significativamente correlacionada com a EAC. (Arq Bras Cardiol. 2020; [online].ahead print, PP.0-0)

Serum prolidase activity in patients with cardiac syndrome X

OBJECTIVE:

Although the underlying mechanism is not yet fully understood, Cardiac Syndrome X (CSX) is defined as microvascular dysfunction. Prolidase plays a role in collagen synthesis. Increased serum prolidase activity (SPA) has been shown to correlate with collagen turnover. Augmented collagen turn-over may be associated with vascular fibrosis and microvascular dysfunction. In this study, we assessed whether there was a correlation between CXS and prolidase activity.

METHODS:

This case-control study included 45 consecutive CSX patients (mean age 50.7±6.5 years, 27 women) and 40 healthy controls (mean age 51.2±6.5 years, 25 women). Prolidase activity was determined with the Human Xaa-Pro Dipeptidase/Prolidase enzyme-linked immunosorbent assay kit (Cusabio Biotech Co. Ltd, China).

RESULTS:

Mean prolidase activity was 898.8±639.1 mU/mL in the CSX group and 434.1±289.8 mU/mL in the control group (p<0.001). In ROC analysis, it was found that the SPA value above 350 mU/mL sympathizes with the diagnosis of CSX.

CONCLUSION:

Increased SPA in CXS patients may play an essential role in the pathophysiology of CSX, leading to augmented oxidative stress and vascular fibrosis, endothelial dysfunction, and increased microvascular resistance.