Background and aims: Low-density lipoprotein (LDL) aggregation is nowadays considered a therapeutic target in atherosclerosis. DP3, the retro-enantio version of the sequence Gly1127-Cys1140 of LRP1, efficiently inhibits LDL aggregation and foam cell in vitro formation. Here, we investigate whether DP3 modulates atherosclerosis in a humanized ApoB100, LDL receptor (LDLR) knockout mice (Ldlr-/-hApoB100 Tg) and determine the potential LDL-related underlying mechanisms.
Methods: Tg mice were fed an HFD for 21 days to induce atherosclerosis and then randomized into three groups that received a daily subcutaneous administration (10 mg/kg) of i) vehicle, ii) DP3 peptide, or iii) a non-active peptide (IP321). The in vivo biodistribution of a fluorescent-labeled peptide version (TAMRA-DP3), and its colocalization with ApoB100 in the arterial intima, was analyzed by imaging system (IVIS) and confocal microscopy. Heart aortic roots were used for atherosclerosis detection and quantification. LDL functionality was analyzed by biochemical, biophysical, molecular, and cellular studies.
Results: Intimal neutral lipid accumulation in the aortic root was reduced in the DP3-treated group as compared to control groups. ApoB100 in LDLs from the DP3 group exhibited an increased percentage of α-helix secondary structures and decreased immunoreactivity to anti-ApoB100 antibodies. LDL from DP3-treated mice were protected against passive and sphingomyelinase (SMase)-induced aggregation, although they still experienced SMase-induced sphingomyelin phospholysis. In patients with familial hypercholesterolemia (FH), DP3 efficiently inhibited both SMase-induced phospholysis and aggregation.
Conclusions: DP3 peptide administration inhibits atherosclerosis by preserving the α-helix secondary structures of ApoB100 in a humanized ApoB100 murine model that mimicks the hallmark of human hypercholesterolemia.
Background and aims: Statin-associated muscle symptoms (SAMS) are a major cause of treatment discontinuation. Clinical Pharmacogenetics Implementation Consortium (CPIC) recommend dose adjustment for statin treatment according to known SLCO1B1 genotype to reduce SAMS. We hypothesized that the association between SLCO1B1 genotype and SAMS is misestimated because of publication bias.
Methods: We searched published systematic reviews on the association between SLCO1B1 genotype and SAMS. To assessed publication bias, we used funnel plot visual inspection, Egger's test, and the Bayes Factor (BFPublication-bias) from Robust Bayesian Meta-Analysis (RoBMA). We compared the odds ratios (ORUncorrected) from meta-analyses before and after correcting for publication bias using trim-and-fill (ORTrim&Fill) and RoBMA (ORRoBMA) methods.
Results: We included 8 cohort and 11 case-control studies, totaling 62 OR of three SLCO1B1 genotypes and six statin drugs. In the primary analysis, the funnel plot was suggestive of publication bias, confirmed by Egger's test (p=0.001) and RoBMA (BFPublication-bias = 18). Correcting the estimate for publication bias resulted in loss of the association, from a significant ORUncorrected (1.31 95%CI [1.13-1.53]) to corrected ORs suggesting no difference: ORTrim&Fill (1.07 95%CI [0.89-1.30]) and ORRoBMA (1.02 95%CI [1.00-1.33]). This suggested that publication bias overestimated the association by 18 % and 23 %, respectively. Similar results were found for genotype rs4149056, simvastatin and atorvastatin.
Conclusions: The effect of the SLCO1B1 genotype on the risk of developing SAMS is overestimated in the published literature, especially rs4149056. This could lead prescribers to incorrectly decreasing statin doses or even avoiding statin use, leading to a loss of the potential cardiovascular benefit of statins.