Vpliv zaviralcev proprotein subtilizin/keksin pretvarjajočega encima 9 (PCSK9) na lipidne subfrakcije, vnetje in arterijsko steno pri bolnikih z zgodnjo koronarno boleznijo

Rehberger Likozar, Andreja (author), Šebeštjen, Miran (mentor)

Lipoprotein(a) (Lp(a)) je pomemben dejavnik tveganja za koronarno bolezen ter prognostični napovednik pri bolnikih po akutnem koronarnem sindromu (AKS), ne glede na vrednosti holesterola nizke gostote (LDL, ang. »low density lipoprotein cholesterol«). Izsledki novejših raziskav so pokazali, da so zaviralci proproteina subtilizin/keksin pretvarjajočega encima 9 (PCSK9) zaenkrat edina zdravila, ki pomembno znižajo serumsko koncentracijo Lp(a) poleg znižanja holesterola LDL, kar je tudi njihova poglavitna lastnost. Nimamo pa podatkov o povezanosti med koncentracijo Lp(a) in genskimi polimorfizmi v genu LPA, kazalniki vnetja, hemostatskimi kazalniki, prizadetostjo arterijske funkcije in odzivom na zdravljenje z različnimi zaviralci PCSK9 pri bolnikih po AKS. Namen naše raziskave je bil proučiti povezanost lipidnih subfrakcij, vnetja in strukturno-funkcijskih lastnosti arterijske stene pri bolnikih s koronarno boleznijo, proučiti vpliv alirokumaba in evolokumaba na lipidne subfrakcije, vnetje in strukturno-funkcijske lastnosti arterijske stene pri bolnikih z zgodnjo koronarno aterosklerozo. Proučevali smo vpliv Lp(a) in genskih polimorfizmov v genu LPA za apolipoprotein(a) na strukturno-funkcijske lastnosti arterijske žilne stene pri preiskovancih s prvim AKS pred 55. letom starosti ter vpliv alirokumaba in evolokumaba na strukturno-funkcijske lastnosti arterijske žilne stene pri preiskovancih po AKS in s koncentracijo Lp(a) nad 1000 mg/L ali Lp(a) nad 600 mg/L in holesterolom LDL nad 2,6 mmol/L. V opazovalno, prospektivno in randomizirano raziskavo, ki je trajala 6 mesecev smo vključili 70 preiskovancev. S stopenjskim vključevanjem (ang. »step-wedge«) in randomizacijo smo zagotovili kontrolno skupino, ki je štela 31 preiskovancev. Vsem preiskovancem smo odvzeli vensko kri za laboratorijske preiskave in izmerili od endotelija odvisno vazodilatacijo brahialne arterije (FMD- ang. »flow-mediated dilatation«), ultrazvočno smo izmerili debelino kompleksa intime-medije (c-IMT- ang. »carotid intima–media thickness«) in togost arterijske žilne stene karotidnih arterij. Rezultati so pokazali, da so genotip GG polimorfizma rs10455872 in haplotipa AT ter GT gena LPA statistično pomembno povezani z vrednostmi Lp(a). Pri preiskovancih z genotipom GG smo beležili bistveno višje vrednosti Lp(a) v primerjavi s preiskovanci, ki so imeli genotip AG. Preiskovanci s haplotipom brez alela AT so imeli pomembno višje vrednosti Lp(a) v primerjavi z nosilci haplotipa z enim alelom ali haplotipa z dvema aleloma AT. Med proučevanimi genotipi/haplotipi in lastnostmi arterijske stene nismo ugotovili statistično pomembnih povezav. Vrednosti Lp(a) so pomembno korelirala tudi s številom KIV-2 ponovitev (r = -0,601; p <0,0001). V kontrolni skupini in skupini, ki je prejemala alirokumab nismo ugotovili statistično pomembnih sprememb v FMD medtem, ko smo v skupini, ki je prejemala evolokumab ugotovili pomembno povečanje FMD (od 11,2 % ±6,8 % do 14,1 % ±6,6 %; p<0,0001). V skupini z evolokumabom smo ugotovili statistično pomembno spremembo v c-IMT in hitrosti pulznega vala (PWV- ang. »pulse wave velocity«). Pri nekadilcih in preiskovancih brez sladkorne bolezni smo beležili pomembno izboljšanje FMD (p=0,003), c-IMT (p=0,027) in PWV (p=0,039) ne glede na to katero zdravilo so prejemali. V kontrolni skupini je bilo 9,7 % aktivnih kadilcev in 20 % diabetikov, v skupini z alirokumabom 25,7 % in 17,1 % ter v skupini z evolokumabom 11,8 % aktivnih kadilcev in 2,9 % diabetikov. V obeh zdravljenih skupinah smo ugotovili pomembno znižanje Lp(a) (alirokumab od 1445 mg/l (1231-1793) do 1219 mg/l (845-1709); evolokumab od 1372 mg/l (1021-1608) do 881 mg/l (800-1433); oba p<0,0001), apolipoproteina B (p<0,001), apolipoproteina A1 (alirokumab p=0,019; evolokumab p=0,028), holesterola LDL (alirokumab od 2,2±0,6 mmol/l do 0,8±0,6 mmol/l; evolokumab od 2,4±0,8 mmol/l do 0,9±0,9 mmol/l; oba p<0,0001) in skupnega holesterola (TC) (p<0,001). V linearnem regresijskem modelu je FMD ob začetku koreliral s starostjo ob prvem AKS, visoko občutljivim C-reaktivnim proteinom in adhezijskim proteinom vaskularnih celic 1 (VCAM1). c-IMT je pomembno koreliral s starostjo ob prvem AKS in Lp(a). PWV je pomembno koreliral s sistoličnim krvnim tlakom (ß=0,332; p=0,002), faktorjem tumorske nekroze alfa, interlevkinom-8. Po zdravljenju smo ugotovili značilno povezanost FMD s sistoličnim krvnim tlakom in VCAM1. PWV in c-IMT sta korelirala s starostjo in sistoličnim krvnim tlakom. Pred zdravljenjem z zaviralci PCSK9 so TC, holesterol LDL in trigliceridi pomembno korelirali s koncentracijo zaviralca s trombinom aktivirane fibrinolize (TAFI) in zaviralca aktivatorja plazminogena 1 (PAI-1). Koncentraciji TC in holesterola LDL sta korelirali s skupnim fibrinolitičnim potencialom. Koncentracija trigliceridov je povezana s koncentracijo interlevkina 6 in interlevkina 8. Nismo pa ugotovili korelacij med Lp(a) in vnetnimi ali hemostatskimi kazalci pred in po zdravljenju. Z našo raziskavo smo ugotovili, da so genotip GG polimorfizma rs10455872 ter haplotipi obeh polimorfizmov (rs10455872 in rs3798220) povezani s koncentracijo Lp(a) pri bolnikih v stabilni fazi po AKS in z zelo visokimi vrednostmi Lp(a). Povezav med genotipi ali haplotipi ter funkcionalnimi in morfološkimi lastnostmi arterijske stene nismo ugotovili. Prav tako nismo ugotovili povezav med koncentracijo Lp(a) ter funkcionalnimi in morfološkimi lastnostmi arterijske žilne stene. Dejavniki tveganja, kot sta kajenje in sladkorna bolezen, oslabijo delovanje alirokumaba in evolokumaba na funkcionalne in morfološke lastnosti arterijske stene. Lastnosti arterijske žilne stene so poleg starosti in arterijskega krvnega tlaka odvisne od koncentracije Lp(a) in vnetja pred zdravljenjem z zaviralci PCSK9. Po zdravljenju pa na lastnosti arterijske žilne stene vplivajo le starost in krvni tlak, od kazalnikov vnetja pa VCAM1. Kazalniki fibrinolize in vnetnih citokinov so povezani s koncentracijo holesterola LDL, ne pa s koncentracijo Lp(a) pred ali po zdravljenju z zaviralci PCSK9.

• Language: Slovenian
• Keywords: lipoprotein (a), endotelijska funkcija, holesterol nizke gostote, koronarna bolezen, ateroskleroza, hemostaza, zaviralci PCSK9, enonukleotidni polimorfizmi v genu LPA rs10455872 in rs3798220, KIV2 aminokislinske ponovitve
• Work type: Doctoral dissertation
• Organization: MF - Faculty of Medicine
• Year: 2024
• PID: 20.500.12556/RUL-155896
• Publication date in RUL: 24.04.2024

Secondary language

• Language: English
• Title: The influence of proportein convertase subtilsin/kexin type 9 (PCSK9) inhibitor therapy on lipid subfractions, inflammation and arterial function in patients with premature coronary artery disease

Abstract

Lipoprotein(a) (Lp(a)) is an important risk factor for coronary artery disease and a prognostic predictor in patients after acute coronary syndrome (ACS), regardless of low-density lipoprotein (LDL) cholesterol levels. The results of recent research have shown that inhibitors of proprotein subtilisin/kexin converting enzyme 9 (PCSK9) are so far the only drugs that significantly lower serum Lp(a) concentration in addition to lowering LDL cholesterol, which is also their main property. However, we have no data on the relationship between Lp(a) concentration and genetic polymorphisms in the LPA gene, inflammation and hemostatic markers, impairment of arterial function and response to treatment with PCSK9 inhibitors in patients after ACS. The aim of our research was to study the relationship between lipid subfractions, inflammation and structural and functional properties of the arterial wall in patients with coronary artery disease, to study the influence of alirocumab and evolocumab on lipid subfractions, inflammation and structural-functional properties of the arterial wall in patients with early coronary atherosclerosis. We studied the influence of Lp(a) and gene polymorphisms in the LPA gene for apolipoprotein(a) on the structural-functional properties of the arterial vessel wall in subjects with a first ACS event before the age of 55, and the influence of alirocumab and evolocumab on the structural-functional properties of the arterial vessel wall in subjects after ACS and with a concentration of Lp(a) above 1000 mg/L or Lp(a) above 600 mg/L and LDL cholesterol above 2.6 mmol/L. We included 70 subjects in an observational, prospective, and randomized study that lasted 6 months. With step-wedge inclusion and randomization, we provided a control group consisting of 31 subjects. We took venous blood from all subjects for laboratory tests and measured the endothelium-dependent vasodilatation of the brachial artery (FMD - "flow-mediated dilatation"), the thickness of the intima-media complex (c-IMT - "carotid intima-media thickness") and the stiffness of the arterial vessel wall of the carotid arteries was measured by ultrasound. The results showed that the GG genotype of the rs10455872 polymorphism and the AT haplotype and the GT of the LPA gene are statistically significantly associated with Lp(a) values. Significantly higher Lp(a) values were recorded in subjects with the GG genotype compared to subjects with the AG genotype. Subjects with the haplotype without the AT allele had significantly higher Lp(a) values compared to the carriers of the haplotype with one allele or the haplotype with two AT alleles. We did not find statistically significant associations between the studied genotypes/haplotypes and arterial wall properties. Lp(a) values were also significantly correlated with the number of KIV-2 repeats (r = -0.601; p <0.0001). We found no statistically significant changes in FMD in the control and alirocumab groups, while a significant increase in FMD was found in the evolocumab group (from 11.2% ±6.8% to 14.1% ±6 .6%; p<0.0001). In the evolocumab group, we found a statistically significant change in c-IMT and pulse wave velocity (PWV). In non-smokers and subjects without diabetes, a significant improvement in FMD (p=0.003), c-IMT (p=0.027) and PWV (p=0.039) was recorded, regardless of which drug they received. There were 9.7% active smokers and 20% diabetics in the control group, 25.7% and 17.1% in the alirocumab group, and 11.8% active smokers and 2.9% diabetics in the evolocumab group. A significant decrease in Lp(a) was found in both treated groups (alirocumab from 1445 mg/l (1231-1793) to 1219 mg/l (845-1709); evolocumab from 1372 mg/l (1021-1608) to 881 mg/ l (800-1433); both p<0.0001), apolipoprotein B (p<0.001), apolipoprotein A1 (alirocumab p=0.019; evolocumab p=0.028), LDL cholesterol (alirocumab from 2.2±0.6 mmol /l to 0.8±0.6 mmol/l; evolocumab from 2.4±0.8 mmol/l to 0.9±0.9 mmol/l; both p<0.0001 and total cholesterol (TC ) (p<0.001). In a linear regression model, FMD at baseline correlated with age at first ACS, high-sensitivity C-reactive protein, and vascular cell adhesion protein 1 (VCAM1). c-IMT significantly correlated with age at first ACS and Lp(a) values. PWV was significantly correlated with systolic blood pressure (β=0.332; p=0.002), tumor necrosis factor alpha and interleukin 8. After treatment, we found a significant association of FMD with systolic blood pressure and VCAM1. PWV and c-IMT correlated with age and systolic blood pressure. Before treatment with PCSK9 inhibitors, TC, LDL cholesterol and triglycerides were significantly correlated with thrombin-activated fibrinolysis inhibitor (TAFI) and plasminogen activator inhibitor 1 (PAI-1) levels. TC and LDL cholesterol concentrations were correlated with total fibrinolytic potential. The concentration of triglycerides is related to the concentration of interleukin 6 and interleukin 8. However, we did not find correlations between Lp(a) and inflammatory or hemostatic markers before and after treatment. These data show that the GG genotype of the rs10455872 polymorphism and the haplotypes of both polymorphisms (rs10455872 and rs3798220) are associated with Lp(a) concentration in patients in the stable phase after ACS and with very high Lp(a) values. We did not find associations between genotypes or haplotypes and functional and morphological properties of the arterial wall. We also found no correlations between Lp(a) concentration and functional and morphological properties of the arterial vessel wall. Risk factors such as smoking, and diabetes weaken the effects of alirocumab and evolocumab on the functional and morphological properties of the arterial wall. In addition to age and arterial blood pressure, arterial vessel wall properties depend on Lp(a) concentration and inflammation before treatment with PCSK9 inhibitors. After treatment, the properties of the arterial vessel wall are affected only by age and blood pressure, and from markers of inflammation, VCAM1. Markers of fibrinolysis and inflammatory cytokines are associated with LDL cholesterol but not Lp(a) levels before or after treatment with PCSK9 inhibitors.

• Keywords: lipoprotein (a), endothelial function, low-density cholesterol, coronary disease, atherosclerosis, hemostasis, PCSK9 inhibitors, single nucleotide polymorphisms in the LPA gene rs10455872 and rs3798220, KIV2 amino acid repeats