Dickkopf-3: a stubborn protector of cardiac hypertrophy

The predictive value of serum Dickkopf-1, Dickkopf-3 level to coronary artery disease and acute coronary syndrome

BACKGROUND

Previous studies have already confirmed the association between Dickkopf (Dkk) protein and the occurrence and progression of atherosclerosis. However, there is limited clinical evidence regarding the serum levels of Dickkopf-1 (Dkk1) and Dickkopf-3 (Dkk3) in relation to atherosclerotic cardiovascular disease (ASCVD), particularly acute coronary syndrome (ACS).

MATERIALS AND METHODS

A total of 88 healthy volunteers and 280 patients with coronary artery disease (CAD) undergoing coronary angiography for angina between October 2021 and October 2022, including 96 cases of stable angina (SA), 96 of unstable angina (UA) and 88 of acute myocardial infarction (AMI) were included finally. The serum concentrations of Dkk1 and Dkk3 were measured using electrochemiluminescence of Meso Scale Discovery. The predictive value of single or combined application of serum Dkk1 and Dkk3 in CAD and ACS were evaluated.

RESULTS

The serum levels of Dkk1 were significantly higher in the SA group, UA group, and AMI group compared to the control group. Multivariable logistic regression analysis demonstrated that elevated serum Dkk1 levels were independent predictive factors for increased risk of CAD and ACS (OR = 1.027, 95%CI = 1.019-1.034, p < 0.001; OR = 1.045, 95%CI = 1.028-1.053, p < 0.001, respectively). Receiver operating characteristic curve (ROC) analysis showed that the optimal cutoff value of serum Dkk1 for predicting ACS was 205 ng/dl, with a sensitivity of 82.6% and specificity of 96.6%. The area under the curve (AUC) was 0.930 (95%CI: 0.899-0.961, p < 0.001). Regarding Dkk3, serum Dkk3 levels were elevated in CAD patients compared to the healthy control group, and significantly higher in ACS patients compared to SA patients. Serum Dkk3 was significantly associated with increased risk of CAD and ACS (OR = 1.131, 95%CI = 1.091-1.173, p < 0.001; OR = 1.201, 95%CI = 1.134-1.271, p < 0.001, respectively). ROC curve analysis showed that the optimal cutoff value of serum Dkk3 for predicting ACS was 50.82 ng/ml, with a sensitivity of 85.9% and specificity of 87.5%. The AUC was 0.925 (95%CI: 0.894-0.956, p < 0.001). When serum Dkk1 and Dkk3 are combined as predictive factors for ACS, the AUC was 0.975.

CONCLUSION

Serum levels of Dkk1 and Dkk3 are significantly associated with an increased risk of CAD and ACS, and they possess predictive value for CAD and ACS. The combination of serum Dkk1 and Dkk3 is a superior predictive factor for CAD and ACS.

The Multifaceted Role of Human Dickkopf-3 (DKK-3) in Development, Immune Modulation and Cancer

The human Dickkopf (DKK) family includes four main secreted proteins, DKK-1, DKK-2, DKK-3, and DKK-4, as well as the DKK-3 related protein soggy (Sgy-1 or DKKL1). These glycoproteins play crucial roles in various biological processes, and especially modulation of the Wnt signaling pathway. DKK-3 is distinct, with its multifaceted roles in development, stem cell differentiation and tissue homeostasis. Intriguingly, DKK-3 appears to have immunomodulatory functions and a complex role in cancer, acting as either a tumor suppressor or an oncogene, depending on the context. DKK-3 is a promising diagnostic and therapeutic target that can be modulated by epigenetic reactivation, gene therapy and DKK-3-blocking agents. However, further research is needed to optimize DKK-3-based therapies. In this review, we comprehensively describe the known functions of DKK-3 and highlight the importance of context in understanding and exploiting its roles in health and disease.

Serum Dickkopf-3 Level Is Inversely Associated with Significant Coronary Stenosis in an Asymptomatic Chinese Cohort

Dickkopp-3 (DKK3) has been identified to play a protection role against atherosclerosis. However, little is known about the relationship between serum DKK3 levels and subclinical coronary atherosclerosis. We aimed to investigate the association of serum DKK3 with coronary stenosis in an asymptomatic Chinese population. A total of 550 Chinese adults aged 40-60 years and without symptoms or histories of cardiovascular diseases were randomly selected to undergo coronary computed tomography angiography. We defined ≥ 50% luminal narrowing as significant coronary stenosis and measured serum DKK3 levels by an enzyme-linked immunosorbent assay (ELISA). Fifty-nine participants had significant coronary stenosis and 223 had < 50% coronary stenosis. Proportions of significant coronary stenosis were 13.7%, 11.4%, and 7.1% in DKK3 tertiles 1-3, respectively (P_trend = 0.0427). In the univariable multinomial logistic regression model, a decreasing DKK3 tertile was associated with significant coronary stenosis with borderline significance (OR: 1.40; 95% confidence intervals (CI): 0.98-1.99, P = 0.0642). In the multivariable regression model, participants in the lowest DKK3 tertile were associated with a 1.42-fold increased risk of significant coronary stenosis than those in the highest DKK3 tertile (OR: 2.42; 95% CI: 1.10-5.33; P = 0.0279) after adjustment for conventional cardiovascular risk factors. In addition, associations between DKK3 and significant coronary stenosis were consistent among subgroups. However, no significant association was found between serum DKK3 levels and < 50% coronary stenosis. Therefore, we have added to the existing evidence that serum DKK3 is inversely associated with the risk of significant coronary stenosis in asymptomatic middle-aged Chinese.

DKK3 attenuates JNK and AP-1 induced inflammation via Kremen-1 and DVL-1 in mice following intracerebral hemorrhage

BACKGROUND

Intracerebral hemorrhage (ICH) is the most devastating stroke subtype, with a poor prognosis and few proven treatments. Neuroinflammation is associated with ICH-induced brain injury and unfavorable outcomes. There is growing evidence that Dickkopf (DKK) 3 plays a key role in the adaptive anti-inflammatory and neuroprotective responses following intracerebral hemorrhage. This study aimed to evaluate the protective effects of DKK3 against brain edema and neuroinflammation in a mice model of ICH.

METHODS

Male, adult CD1 mice were subjected to sham or ICH surgery using a collagenase injection model. ICH animals received either recombinant DKK3, Kremen-1 siRNA, or DVL-1 siRNA. The neurobehavioral deficits were evaluated at 24 h, 72 h, and 28 days after ICH induction. Western blot and immunofluorescence were employed to examine the expression and localization of DKK3, Kremen-1, Dishevelled-1 (DVL-1), c-JUN N-terminal kinase (JNK), Activator protein-1 (AP-1), cleaved caspase-1, NF-κB, and IL-1β in the brain.

RESULTS

The expression of endogenous DKK3 and DVL-1 was transiently decreased after ICH compared to that in the sham group. Compared to the mice of ICH, exogenous rDKK3 administration reduced the brain water content and affected the neurological functions in ICH mice. Moreover, DKK3 was colocalized with Kremen-1 in microglia. Using a Kremen-1 or DVL-1 siRNA-induced in vivo knockdown approach, we demonstrated that the effects of DKK3 against ICH were mediated, at least partly, by the Kremen-1 and DVL-1 pathways.

CONCLUSIONS

DKK3 improves the neurological outcomes, potentially by decreasing JNK/AP-1-mediated inflammation, thereby ameliorating the short- and long-term sequelae after ICH.

A Cytokine-Like Protein Dickkopf-Related Protein 3 Is Atheroprotective

Supplemental Digital Content is available in the text.

Background:

Dickkopf-related protein 3 (DKK3) is a secreted protein that is involved in the regulation of cardiac remodeling and vascular smooth muscle cell differentiation, but little is known about its role in atherosclerosis.

Methods:

We tested the hypothesis that DKK3 is atheroprotective using both epidemiological and experimental approaches. Blood DKK3 levels were measured in the Bruneck Study in 2000 (n=684) and then in 2005 (n=574). DKK3-deficient mice were crossed with apolipoprotein E^-/- mice to evaluate atherosclerosis development and vessel injury-induced neointimal formation. Endothelial cell migration and the underlying mechanisms were studied using in vitro cell culture models.

Results:

In the prospective population-based Bruneck Study, the level of plasma DKK3 was inversely related to carotid artery intima-media thickness and 5-year progression of carotid atherosclerosis independently from standard risk factors for atherosclerosis. Experimentally, we analyzed the area of atherosclerotic lesions, femoral artery injury-induced reendothelialization, and neointima formation in both DKK3^-/-/apolipoprotein E^-/- and DKK3^+/+/apolipoprotein E^-/- mice. It was demonstrated that DKK3 deficiency accelerated atherosclerosis and delayed reendothelialization with consequently exacerbated neointima formation. To explore the underlying mechanisms, we performed transwell and scratch migration assays using cultured human endothelial cells, which exhibited a significant induction in cell migration in response to DKK3 stimulation. This DKK3-induced migration activated ROR2 and DVL1, activated Rac1 GTPases, and upregulated JNK and c-jun phosphorylation in endothelial cells. Knockdown of the ROR2 receptor using specific siRNA or transfection of a dominant-negative form of Rac1 in endothelial cells markedly inhibited cell migration and downstream JNK and c-jun phosphorylation.

Conclusions:

This study provides the evidence for a role of DKK3 in the protection against atherosclerosis involving endothelial migration and repair, with great therapeutic potential implications against atherosclerosis.