Endogenous PCSK9 may influence circulating CD45neg/CD34bright and CD45neg/CD34bright/CD146neg cells in patients with type 2 diabetes mellitus

Investigating the Relationship Between Lipid-Lowering Agents and the Complications of Diabetic Retinopathy

BACKGROUND AND OBJECTIVE

As the therapeutic efficacy of lipid-lowering agents (LLA) against diabetic retinopathy (DR) remains controversial, this study aimed to evaluate whether various LLA therapies are associated with a reduced risk of DR progression.

PATIENTS AND METHODS

This retrospective study of the medical records of adults with type 2 diabetes mellitus and DR compared the risk of adverse progression of DR between patients who received statins, fibrates, proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors, and no LLA (control).

RESULTS

Patients in the statin cohort had a reduced rate of progression to proliferative DR compared to controls (HR = 0.30, CI = 0.11 to 0.83). The PCSK9 inhibitor cohort had a reduced risk of progressing to other secondary complications of DR compared to the control (RR = 0.52, CI = 0.43 to 0.64), statin (RR = 0.69, CI = 0.61 to 0.79), and fibrate (RR = 0.67, CI = 0.59 to 0.77) cohorts.

CONCLUSIONS

These findings suggest use of statins and PCSK9 inhibitors are associated with a reduced risk of adverse progression of DR. [Ophthalmic Surg Lasers Imaging Retina 2024;55:706-713.].

Circulating Endothelial Progenitor Cells in Patients with Established Cardiovascular Disease Treated with PCSK9 Monoclonal Antibodies

Background

The role of circulating endothelial progenitor cells (cEPCs) in vascular repair and their association to cardiovascular protection is well established.

Objectives

We examined the effect of proprotein convertase subtilisin kexin type 9 monoclonal antibodies (PCSK9 mAb) on cEPCs in adults with hypercholesterolemia and cardiovascular disease, aiming to establish a pleotropic class effect.

Methods

Non-interventional prospective study in patients with cardiovascular disease treated with either evolocumab or alirocumab. Patients were sampled for cEPCs at baseline, 1- and 3-months following initiation of PCSK9 mAb. cEPCs were assessed using flow cytometry by expression of CD34/CD133 and vascular endothelial growth factor receptor (VEGFR)-2, and functionally by formation of colony forming units (CFUs) and by Mitochondrial Tetrazolium (MTT) assay, indicative of cEPCs viability.

Results

51 patients (median age 67 (IQR 63,74) years;63 % male, median low-density lipoprotein-cholesterol (LDL-C) 125 (102,165) mg/dL) were initiated on PCSK9 mAb therapy (evolocumab n = 22, alirocumab n = 29) for secondary prevention. Following 3-month treatment with PCSK9 mAb, there was an increase in CD34(+)VEGFR-2(+) and CD133(+)VEGFR-2(+) levels (0.50 % [IQR 0.30,1.04] to 1.36 % [0.89, 1.73], p < 0.001 and 0.57 % [0.25,0.88] to 1.18 % [0.74,1.66], p < 0.001, respectively). Functionally, increase in EPCs-CFUs was evident (0.5 [0.0,1.0] to 2.0 [1.5,2.5], p < 0.001) with concomitant increase in MTT (0.11 [0.09,0.15] to 0.17 [0.12,0.21], p < 0.001). Stratifying by PCSK9 mAb, both agents were associated with an increase in cEPCs level and function.

Conclusions

In hypercholesterolemic patients with cardiovascular disease treated with PCSK9 mAb, there is an increase in cEPCs levels and function from baseline levels. These findings, which persist in both evolocumab and alirocumab, might suggest a novel pleiotropic class effect.

Endothelial progenitor cells as biomarkers of diabetes-related cardiovascular complications

Diabetes mellitus (DM) constitutes a chronic metabolic disease characterized by elevated levels of blood glucose which can also lead to the so-called diabetic vascular complications (DVCs), responsible for most of the morbidity, hospitalizations and death registered in these patients. Currently, different approaches to prevent or reduce DM and its DVCs have focused on reducing blood sugar levels, cholesterol management or even changes in lifestyle habits. However, even the strictest glycaemic control strategies are not always sufficient to prevent the development of DVCs, which reflects the need to identify reliable biomarkers capable of predicting further vascular complications in diabetic patients. Endothelial progenitor cells (EPCs), widely known for their potential applications in cell therapy due to their regenerative properties, may be used as differential markers in DVCs, considering that the number and functionality of these cells are affected under the pathological environments related to DM. Besides, drugs commonly used with DM patients may influence the level or behaviour of EPCs as a pleiotropic effect that could finally be decisive in the prognosis of the disease. In the current review, we have analysed the relationship between diabetes and DVCs, focusing on the potential use of EPCs as biomarkers of diabetes progression towards the development of major vascular complications. Moreover, the effects of different drugs on the number and function of EPCs have been also addressed.

Rationale and design of a randomized controlled trial: The effect of intensive lipid-lowering therapy with PCSK9 inhibitor on endothelial-coverage of stent strut after percutaneous coronary intervention (PCI) for patients with acute coronary syndrome (ACS): Optical coherence tomography (OCT) study (PIECES-OCT study)

BACKGROUND

For the patients with acute coronary syndrome (ACS) undergoing percutaneous coronary intervention (PCI), dual antiplatelet therapy (DAPT) for at least 1 year is recommended in the guidelines to minimize the risk of stent thrombosis. Persistently uncovered stent strut means delayed neointima formation and extend the window of time in which the stent is prone to thrombosis. Previous studies showed that statins could improve post-stenting strut endothelial coverage for patients undergoing PCI. However, there are lack of evidences on whether early initiation of proprotein convertase subtilisin/Kexin type 9 monoclonal antibody (PCSK9mAb) after PCI in ACS patients can further improve the rate of stent strut coverage on the background of oral lipid-lowering therapy (LLT).

METHODS

This is a single-center, randomized trial to enroll 36 patients undergoing PCI with a clinical diagnosis of non-ST-segment elevation ACS. The baseline level of low-density lipoprotein cholesterol (LDL-C) of these patients are between 1.4 mmol/L and 3.4 mmol/L. Patients will be assigned to intensive lipid-lowering therapy (LLT) with PCSK9mAb group and conventional LLT without PCSK9mAb group for 12 weeks in a clinical follow-up setting according to 1: 1 randomization. the rate of stent strut endothelial coverage by optical coherence tomography (OCT) examination at 12 weeks after enrollment between the groups will be compared.

CONCLUSION

This will be the first study to investigate changes in the rate of stent strut endothelial coverage under intensive LLT with PCSK9mAb by OCT examination in ACS patients undergoing PCI. The finding of this study will provide clinical evidence for future research about the hypothesis of a novel strategy of "intensive LLT (PCSK9mAb + statin ± ezetimibe) combined with shortened DAPT duration" for ACS patients undergoing PCI.Clinical Trial Registration: URL: https://www.clinicaltrials.gov. Unique identifier: ChiCTR2200063395.

Effects of Lipid Lowering Therapy Optimization by PCSK9 Inhibitors on Circulating CD34+ Cells and Pulse Wave Velocity in Familial Hypercholesterolemia Subjects without Atherosclerotic Cardiovascular Disease: Real-World Data from Two Lipid Units

Background: Circulating CD34+ progenitor cells (CD34+CPCs) are characterized by pronounced tissue regeneration activity. Dyslipidemic subjects seemed to have reduced CD34+CPCs, and statin therapy appeared to restore their levels. We aimed to evaluate the effects of PCSK9 inhibitors (PCSK9-i) on CD34+CPCs and pulse wave velocity (PWV) in a cohort of heterozygous familial hypercholesterolemia (HeFH) subjects. Methods: We determined CD34+ cell count and its change after PCSK9-i in 30 selected HeFH subjects and 30 healthy controls. Lipid profile and PWV were evaluated at baseline (T0), 6 months after intensive lipid lowering strategy (statin plus ezetimibe, T1), and after 6 months of optimized therapy with PCSK9-i (T2); CD34+ cell count was reported at T1 and T2. Results: At T1, the median value of CD34+ cells was not significantly different between HeFH subjects and controls, and the same result was obtained at T2. PWV was significantly reduced at T1 (ΔPWV − 14.8%, p < 0.001 vs. T0) and T2 (ΔPWV − 10.96%, p < 0.001 vs. T1). Dividing HeFH subjects into two groups of high- and low-CD34+ cell count, CD34+CPCs appeared to be polarized with a significant difference between the two groups (1.2 (0.46) vs. 4.74 (1.92), p < 0.001), also with respect to controls (both p < 0.001). This polarization was no longer observed at T2, and neither with respect to controls. ΔCD34+ was +67.4% in the low-CD34+ group and −39.24% in the high-CD34+ group (p < 0.001). Lastly, we found a significant correlation between ΔCD34+ cell number and ΔPWV in HeFH subjects (rho = −0.365, p < 0.05), particularly in the low-CD34+ group (rho = −0.681, p < 0.001). Conclusion: PCSK9-i exhibited favorable effects on CD34 + CPCs as was on PWV values in a cohort of FH subjects. Our preliminary findings suggest a possible positive role of this novel lipid-lowering strategy on vascular homeostasis.

Identification of candidate biomarkers and pathways associated with type 1 diabetes mellitus using bioinformatics analysis

Type 1 diabetes mellitus (T1DM) is a metabolic disorder for which the underlying molecular mechanisms remain largely unclear. This investigation aimed to elucidate essential candidate genes and pathways in T1DM by integrated bioinformatics analysis. In this study, differentially expressed genes (DEGs) were analyzed using DESeq2 of R package from GSE162689 of the Gene Expression Omnibus (GEO). Gene ontology (GO) enrichment analysis, REACTOME pathway enrichment analysis, and construction and analysis of protein–protein interaction (PPI) network, modules, miRNA-hub gene regulatory network and TF-hub gene regulatory network, and validation of hub genes were performed. A total of 952 DEGs (477 up regulated and 475 down regulated genes) were identified in T1DM. GO and REACTOME enrichment result results showed that DEGs mainly enriched in multicellular organism development, detection of stimulus, diseases of signal transduction by growth factor receptors and second messengers, and olfactory signaling pathway. The top hub genes such as MYC, EGFR, LNX1, YBX1, HSP90AA1, ESR1, FN1, TK1, ANLN and SMAD9 were screened out as the critical genes among the DEGs from the PPI network, modules, miRNA-hub gene regulatory network and TF-hub gene regulatory network. Receiver operating characteristic curve (ROC) analysis confirmed that these genes were significantly associated with T1DM. In conclusion, the identified DEGs, particularly the hub genes, strengthen the understanding of the advancement and progression of T1DM, and certain genes might be used as candidate target molecules to diagnose, monitor and treat T1DM.

The Role of Endothelial Progenitor Cells in Atherosclerosis and Impact of Anti-Lipemic Treatments on Endothelial Repair

Cardiovascular complications are associated with advanced atherosclerosis. Although atherosclerosis is still regarded as an incurable disease, at least in its more advanced stages, the discovery of endothelial progenitor cells (EPCs), with their ability to replace old and injured cells and differentiate into healthy and functional mature endothelial cells, has shifted our view of atherosclerosis as an incurable disease, and merged traditional theories of atherosclerosis pathogenesis with evolving concepts of vascular biology. EPC alterations are involved in the pathogenesis of vascular abnormalities in atherosclerosis, but many questions remain unanswered. Many currently available drugs that impact cardiovascular morbidity and mortality have shown a positive effect on EPC biology. This review examines the role of endothelial progenitor cells in atherosclerosis development, and the impact standard antilipemic drugs, including statins, fibrates, and ezetimibe, as well as more novel treatments such as proprotein convertase subtilisin/kexin type 9 (PCSK9) modulating agents and angiopoietin-like proteins (Angtpl3) inhibitors have on EPC biology.