The association of insulin-like growth factor-1 with severity of coronary artery disease

Cardiometabolic Risk Factors and Benign Gynecologic Disorders

Importance

While it has long been known that polycystic ovarian syndrome is associated with cardiometabolic risk factors (CMRFs), there is emerging evidence that other benign gynecologic conditions, such as uterine leiomyomas, endometriosis, and even hysterectomy without oophorectomy, can be associated with CMRFs. Understanding the evidence and mechanisms of these associations can lead to novel preventive and therapeutic interventions.

Objective

This article discusses the evidence and the potential mechanisms mediating the association between CMRFs and benign gynecologic disorders.

Evidence Acquisition

We reviewed PubMed, EMBASE, Scopus, and Google Scholar databases to obtain plausible clinical and biological evidence, including hormonal, immunologic, inflammatory, growth factor-related, genetic, epigenetic, atherogenic, vitamin D-related, and dietary factors.

Results

Cardiometabolic risk factors appear to contribute to uterine leiomyoma pathogenesis. For example, obesity can modulate leiomyomatous cellular proliferation and extracellular matrix deposition through hyperestrogenic states, chronic inflammation, insulin resistance, and adipokines. On the other hand, endometriosis has been shown to induce systemic inflammation, thereby increasing cardiometabolic risks, for example, through inducing atherosclerotic changes.

Conclusion and Relevance

Clinical implications of these associations are 2-fold. First, screening and early modification of CMRFs can be part of a preventive strategy for uterine leiomyomas and hysterectomy. Second, patients diagnosed with uterine leiomyomas or endometriosis can be screened and closely followed for CMRFs and cardiovascular disease.

Effects of IGF-1 on the Cardiovascular System

:

Cardiovascular (CV) diseases are the most common health problems worldwide, with a permanent increase in incidence. Growing evidence underlines that insulin-like growth factor 1 (IGF-1) is a very important hormone responsible for normal CV system physiology. IGF-1 is an anabolic growth hormone, responsible for cell growth, differentiation, proliferation, and survival. Despite systemic effects, IGF-1 exerts a wide array of influences in the CV system affecting metabolic homeostasis, vasorelaxation, cardiac contractility and hypertrophy, autophagy, apoptosis, and antioxidative processes. The vasodilatory effect of IGF-1, is achieved through the regulation of the activity of endothelial nitric oxide synthase (eNOS) and, at least partly, through enhancing inducible NOS (iNOS) activity. Also, IGF-1 stimulates vascular relaxation through regulation of sodium/potassiumadenosine- triphosphatase. Numerous animal studies provided evidence of diverse influences of IGF-1 in the CV system such as vasorelaxation, anti-apoptotic and prosurvival effects. Human studies indicate that low serum levels of free or total IGF-1 contribute to an increased risk of CV and cerebrovascular disease. Large human trials aiming at finding clinical efficacy and outcome of IGF-1-related therapy are of great interest.

:

We look forward to the development of new IGF 1 therapies with minor side effects. In this review, we discuss the latest literature data regarding the function of IGF-1 in the CV system in the physiological and pathophysiological conditions.

Insulin-like growth factor-binding protein 7 (IGFBP 7) as a new biomarker in coronary heart disease

PURPOSE

The role of insulin-like growth factor-binding protein-7 (IGFBP-7) in atherosclerosis is still not well-known. The objective of this study was to find out the following: 1) whether IGFBP-7 may act as a biomarker of coronary artery disease (CAD) occurrence and extent; 2) whether IGFBP-7 is potentially related to the classical and new markers of cardiovascular risk (carotid intima-media thickness - cIMT); 3) whether IGFBP-7 may be a marker of mortality in the group of patients with myocardial infarction (MI).

MATERIALS/METHODS

The study group consisted of 212 patients with MI and 75 patients with stable CAD, the control group included 100 healthy volunteers. IGFBP-7 serum concentration was measured.

RESULTS

IGFBP-7 value was considerably higher in the study group (MI and CAD patients - 35.1 ng/ml (P = 0.000001) and 32.7ng/ml (P = 0.0001), respectively), than in the controls - 25.2ng/ml. No statistically significant differences between IGFBP-7 concentrations in the MI and CAD group were found. No relationship between IGFBP-7 and the coronary lesions advancement in the study group was observed. No changes in IGFBP-7 concentration in the MI patients during hospitalization were observed. In the group of MI patients who died during follow-up, a considerably higher cIMT values were found whereas no statistically significant difference was observed in relation to IGFBP-7 (34.6 vs. 35.2 ng/ml).

CONCLUSIONS

IGFBP-7 is a good biomarker of CAD occurrence but not of its advancement. We demonstrated the existence of the relation between higher IGFBP-7 concentration and the selected classical risk factors of cardiovascular events as well as cIMT values. IGFBP-7 cannot serve as a marker of acute ischemia. Also, IGFBP-7 was not confirmed as a predictor of mortality in the MI patients.

Involvement of endothelial nitric oxide synthase pathway in IGF‑1 protects endothelial progenitor cells against injury from oxidized LDLs

A high level of oxidized low‑density lipoproteins (oxLDLs) is an independent risk factor for cardiovascular disease. The aim of the present study was to investigate whether insulin‑like growth factor‑1 (IGF‑1) protected endothelial progenitor cells (EPCs) from injury caused by ox‑LDLs, and whether the endothelial nitric oxide synthase (eNOS)/nitric oxide (NO) pathway was involved in this process. EPCs were isolated from human peripheral blood and characterized. In order to evaluate the effect of IGF‑1 on EPCs, cells were incubated with ox‑LDLs (100 mg/ml) for 24 h to induce a model of EPC dysfunction in vitro, which demonstrated a decrease in the number of EPCs, concomitant with increased apoptosis and decreased proliferation rates. IGF‑1 dose‑dependently increased the number of EPCs. Concurrently, IGF‑1 decreased the levels of apoptosis of EPCs and improved EPCs proliferation following ox‑LDLs challenge. In addition, IGF‑1 significantly increased NO levels in ox‑LDLs‑treated EPCs, accompanied by an upregulation in eNOS expression. The protective effects of IGF‑1 on EPCs and NO production were abolished by L‑NAME, a specific eNOS inhibitor. These results suggested that IGF‑1 protects EPCs from dysfunction induced by oxLDLs through a mechanism involving the eNOS/NO pathway.

Association of IGF-1 with coronary collateral circulation in stable coronary artery disease

Aim: The aim of the present study is to evaluate the relationship between coronary collateral circulation (CCC) grade and serum IGF-1 levels in patients diagnosed with stable coronary artery disease. Methods: Totally, 190 consecutive patients with stable coronary artery disease who underwent coronary angiography were included in this study. Results: The patients with good CCC had significantly higher IGF-1 levels compared with the poor ones. On the contrary, hs-CRP was significantly lower in the good CCC group. We also demonstrated that IGF-1 level was significantly related with the grade of CCC. Conclusion: We believe that measurement of IGF-1 level may help clinicians for predicting CCC development.