Plasma FGF23 and Calcified Atherosclerotic Plaque in African Americans with Type 2 Diabetes Mellitus

Relationships of serum FGF23 and α-klotho with atherosclerosis in patients with type 2 diabetes mellitus

BACKGROUND

Compelling evidence suggests that calcium/phosphorus homeostasis-related parameters may be linked to diabetes mellitus and cardiovascular events. However, few studies have investigated the association of fibroblast growth factor 23 (FGF23), α-klotho and FGF23/α-klotho ratio with atherosclerosis in patients with type 2 diabetes mellitus (T2DM).

OBJECTIVE

This study was designed to evaluate whether FGF23, α-klotho and FGF23/α-klotho ratio are associated with T2DM and further to explore the relationships between these three factors and atherosclerosis in Chinese patients with T2DM.

METHODS

Serum FGF23 and α-klotho levels were measured via an enzyme-linked immunosorbent assay (ELISA) kit, and the carotid intima-media thickness (CIMT) was assessed via high-resolution color Doppler ultrasonography. The associations of serum FGF23, α-klotho and FGF23/α-klotho ratio with atherosclerosis in T2DM patients were evaluated using multivariable logistic regression models.

RESULTS

This cross-sectional study involved 403 subjects (207 with T2DM and 196 without T2DM), 41.7% of the patients had atherosclerosis, and 67.2% of the carotid intima were thickened to a thickness greater than 0.9 mm. Compared with those in the lowest tertile, higher tertiles of FGF23 levels and FGF23/α-klotho ratio were positively associated with T2DM after adjusting for covariates, and serum α-klotho concentration was inversely correlated with T2DM (all P values < 0.01). Moreover, elevated serum FGF23 levels and FGF23/α-klotho ratio were positively associated with CIMT and carotid atherosclerosis in T2DM patients (all P values < 0.01). Further spline analysis similarly revealed linear dose‒response relationship (all P values < 0.01). And there was still significant differences in CIMT and carotid atherosclerosis between the highest group of α-klotho and the reference group in T2DM patients (P values = 0.05).

CONCLUSIONS

T2DM was positively linearly related to serum FGF23 concentration and FGF23/α-klotho ratio, and negatively correlated with serum α-klotho concentration. Furthermore, both FGF23 and FGF23/α-klotho ratio were positively correlated with CIMT and atherosclerosis in T2DM patients, while α-klotho was inversely correlated with both CIMT and atherosclerosis, although the associations were not completely significant. Prospective exploration and potential mechanisms underlying these associations remain to be further elucidated.

Advances in FGFs for diabetes care applications

BACKGROUND

Diabetes mellitus (DM) is an endocrine and metabolic disease caused by a variety of pathogenic factors, including genetic factors, environmental factors and behavior. In recent decades, the number of cases and the prevalence of diabetes have steadily increased, and it has become one of the most threatening diseases to human health in the world. Currently, insulin is the most effective and direct way to control hyperglycemia for diabetes treatment at a low cost. However, hypoglycemia is often a common complication of insulin treatment. Moreover, with the extension of treatment time, insulin resistance, considered the typical adverse symptom, can appear. Therefore, it is urgent to develop new targets and more effective and safer drugs for diabetes treatment to avoid adverse reactions and the insulin tolerance of traditional hypoglycemic drugs.

SCOPE OF REVIEW

In recent years, it has been found that some fibroblast growth factors (FGFs), including FGF1, FGF19 and FGF21, can safely and effectively reduce hyperglycemia and have the potential to be developed as new drugs for the treatment of diabetes. FGF23 is also closely related to diabetes and its complications, which provides a new approach for regulating blood glucose and solving the problem of insulin tolerance.

MAJOR CONCLUSIONS

This article reviews the research progress on the physiology and pharmacology of fibroblast growth factor in the treatment of diabetes. We focus on the application of FGFs in diabetes care and prevention.

Novel Cardiovascular Risk Factors in Patients with Diabetic Kidney Disease

Patients with diabetic kidney disease (DKD) are at very high risk for cardiovascular events. Only part of this increased risk can be attributed to the presence of diabetes mellitus (DM) and to other DM-related comorbidities, including hypertension and obesity. The identification of novel risk factors that underpin the association between DKD and cardiovascular disease (CVD) is essential for risk stratification, for individualization of treatment and for identification of novel treatment targets.In the present review, we summarize the current knowledge regarding the role of emerging cardiovascular risk markers in patients with DKD. Among these biomarkers, fibroblast growth factor-23 and copeptin were studied more extensively and consistently predicted cardiovascular events in this population. Therefore, it might be useful to incorporate them in risk stratification strategies in patients with DKD to identify those who would possibly benefit from more aggressive management of cardiovascular risk factors.

Role of Glycosylation in Vascular Calcification

Glycosylation is an important step in post-translational protein modification. Altered glycosylation results in an abnormality that causes diseases such as malignancy and cardiovascular diseases. Recent emerging evidence highlights the importance of glycosylation in vascular calcification. Two major types of glycosylation, N-glycosylation and O-glycosylation, are involved in vascular calcification. Other glycosylation mechanisms, which polymerize the glycosaminoglycan (GAG) chain onto protein, resulting in proteoglycan (PG), also have an impact on vascular calcification. This paper discusses the role of glycosylation in vascular calcification.

Cardiovascular risk assessment and association with novel biomarkers in patients with Type 2 diabetes mellitus

Aim: To investigate the association between cardiovascular risk and biomarkers in patients with Type 2 diabetes (T2DM). Methods: Cross-sectional study, with evaluation of traditional and new biomarkers (serum FGF-23, Syndecan-1 [Sdc-1] and vascular cell adhesion molecule-1 [VCAM-1] and urinary VEGF and kidney injury molecule-1 [KIM-1]) and risk scores (Framingham-FRS and UK Prospective Diabetes Study [UKPDS]). Results: 128 diabetics were included, with predominance of high risk by FRS and low risk by UKPDS. There was an independent association of VCAM-1 and VEGF with higher risk by FRS-lipids and UKPDS. Conclusion: There was an independent association of VCAM-1 and VEGF with higher cardiovascular risk, showing a subclinical endothelial dysfunction in T2DM. The inclusion of novel biomarkers to risk scores may increase accuracy when assessing cardiovascular risk of diabetic individuals.

FGF-23 correlates with endocrine and metabolism dysregulation, worse cardiac and renal function, inflammation level, stenosis degree, and independently predicts in-stent restenosis risk in coronary heart disease patients underwent drug-eluting-stent PCI

Background

The present study aimed to assess the correlation of fibroblast growth factor (FGF)-23 expression with clinical characteristics, then further explore its value in predicting 2-year in-stent restenosis (ISR) risk in coronary heart disease (CHD) patients underwent percutaneous coronary intervention (PCI) with drug-eluting stent (DES).

Methods

In this prospective, single-center, observational study, totally 214 CHD patients treated by PCI with DES were consecutively recruited, and peripheral blood samples were collected prior to PCI with DES for serum samples isolation. Following, FGF-23 level in the serum samples was detected via enzyme linked-immuno-sorbent Assay. The follow-up coronary angiography was performed at 1 year and 2 years after PCI or if suspected ISR symptoms occurred.

Results

FGF-23 was positively correlated with fasting blood-glucose, insulin resistance, serum creatinine, serum uric acid, LDL-C, high-sensitivity C-reactive protein, cardiac troponin I and N-terminal-proB-type natriuretic peptide, while was negatively associated with HDL-C and left ventricular ejection fraction (all P < 0.01). Furthermore, FGF-23 was positively correlated with hypercholesteremia, hyperuricemia and family history of CAD (all P < 0.05). However, it did not correlate with other chronic complications, biochemical indexes, lesion features or PCI parameters (all P > 0.05). Moreover, FGF-23 level was higher in 2-year ISR patients (n = 38) compared to 2-year non-ISR patients (n = 176) (P < 0.001), and receiver operating characteristic curve indicated that FGF-23 was of good value in predicting 2-year ISR risk (AUC 0.828, 95% CI 0.761–0.896).

Conclusion

FGF-23 correlates with endocrine and metabolism dysregulation, worse cardiac and renal function, inflammation level, stenosis degree of target lesion, and serves as an independent risk factor for 2-year ISR risk in CHD patients underwent PCI with DES.

Fibroblast Growth Factor 23 and Adverse Clinical Outcomes in Type 2 Diabetes: a Bitter-Sweet Symphony

PURPOSE OF REVIEW

Fibroblast growth factor 23 (FGF23) is a key phosphate-regulating hormone that has been associated with adverse outcomes in patients with chronic kidney disease (CKD). Emerging data suggest that FGF23 plays a specific role in type 2 diabetes, partly independent of kidney function. We aimed to summarize current literature on the associations between FGF23 and outcomes in patients with type 2 diabetes with or without CKD.

RECENT FINDINGS

Several cohort studies have shown strong associations between plasma FGF23 and cardiovascular outcomes in diabetic CKD. Moreover, recent data suggest that FGF23 are elevated and may also be a risk factor for cardiovascular disease and mortality in type 2 diabetes patients without CKD, although the magnitude of the association is smaller than in CKD patients. Diabetes-related factors may influence plasma FGF23 levels, and a higher FGF23 levels seem to contribute to a higher cardiovascular and mortality risk in patients with type 2 diabetes. Although this risk may be relevant in diabetic individuals with preserved kidney function, it is strongly accentuated in diabetic nephropathy. Future studies should clarify if FGF23 is merely a disease severity marker or a contributor to adverse outcomes in type 2 diabetes and establish if antidiabetic medication can modify FGF23 levels.

Biomarkers of vascular disease in diabetes: the adipose-immune system cross talk

Experimental and clinical studies aimed at investigating the mechanism(s) underlying vascular complications of diabetes indicate that a great number of molecules are involved in the pathogenesis of these complications. Most of these molecules are inflammatory mediators or markers generated by immune or adipose tissue. Some of them, i.e. resistin and sortilin, have been shown to be involved in the cross talk between adipocytes and inflammatory cells. This interaction is an attractive area of research, particularly in type 2 diabetes and obesity. Other proteins, such as adiponectin and visfatin, appear to be more promising as possible vascular markers. In addition, some molecules involved in calcium/phosphorus metabolism, such as klotho and FGF23, have an involvement in the pathogenesis of diabetic vasculopathy, which appears to be dependent on the degree of vascular impairment. Inflammatory markers are a promising tool for treatment decisions while measuring plasma levels of adipokines, sortilin, Klotho and FGF23 in adequately sized longitudinal studies is expected to allow a more precise characterization of diabetic vascular disease and the optimal use of personalized treatment strategies.

Association of bone mineral density and trabecular bone score with cardiovascular disease

Traditionally, osteoporosis and cardiovascular disease (CVD) are considered as separate chronic diseases. Increasing evidence now links osteoporosis with hypertension, abnormal lipid metabolism, atherosclerosis, vascular calcification (VC), and congestive heart failure. VC coexists with bone loss, and aortic calcification is a strong predictor of low bone mineral density (BMD) and fragility fractures. The same holds true for coronary artery calcification (CAC): the lower the BMD, the higher the CAC. Trabecular bone score (TBS) iNsight software can analyze the existing BMD database to obtain the bony microstructure score (TBS). Many TBS-related studies include fracture risk, normal aging, diabetes, potential genes, obesity, and asthma severity prediction. The inverse relationship of TBS to VC may provide insight into bone–vascular interactions in chronic kidney disease. A higher TBS has been associated with moderate, but not high, CAC. One explanation is that bone microstructural remodeling becomes more active during early coronary calcification. Increased risk of 10-year likelihood of hip fracture and major osteoporotic fracture as estimated by the fracture risk assessment tool FRAX^® is significantly and independently associated with more severe CAC scores. Dual-energy X-ray absorptiometry and FRAX^® can be used to predict fracture risk and CAC scores, identifying patients who may benefit from early intervention. This review will discuss the relationship and possible mechanism of BMD, TBS, and FRAX^® with CVD and VC or CAC.

Fibroblast growth factor 23 expression in human calcified vascular tissues

Vascular calcification is a major risk for cardiovascular disease and implies the transformation of smooth muscle cells to an osteoblastic phenotype as a consequence of dysregulation of calcium and phosphate metabolism. Fibroblast growth factor (FGF) 23 is the most potent phosphate regulator. Observational studies suggest that high levels of FGF23 are related to cardiovascular morbidity and mortality. In this work, we determined the levels of both the intact and the carboxi-terminal fragments of circulating FGF23 in 133 patients with established cardiovascular disease, the expression of FGF23, its receptors 1 and 3, and its co-receptor Klotho in vascular fragments of aorta, carotid and femoral in 43 out of this group of patients, and in a control group of 20 organ donors. Patients with atherosclerosis and vascular calcification presented increased levels of FGF23 respect to the control group. Vascular immunoreactivity for FGF23 was also significantly increased in patients with vascular calcification as compared to patients without calcification and to controls. Finally, gene expression of FGF23 and RUNX2 were also higher and directly related in vascular samples with calcification. Conversely, expression of Klotho was reduced in patients with cardiovascular disease when comparing to controls. In conclusion, our findings link the calcification of the vascular tissue with the expression of FGF23 in the vessels and with the elevation of circulating levels this hormone.

Regulation of fibroblast growth factor 23 (FGF23) in health and disease

Fibroblast growth factor 23 (FGF23) is mainly produced in the bone and, upon secretion, forms a complex with a FGF receptor and coreceptor αKlotho. FGF23 can exert several endocrine functions, such as inhibiting renal phosphate reabsorption and 1,25-dihydroxyvitamin D3 production. Moreover, it has paracrine activities on several cell types, including neutrophils and hepatocytes. Klotho and Fgf23 deficiencies result in pathologies otherwise encountered in age-associated diseases, mainly as a result of hyperphosphataemia-dependent calcification. FGF23 levels are also perturbed in the plasma of patients with several disorders, including kidney or cardiovascular diseases. Here, we review mechanisms controlling FGF23 production and discuss how FGF23 regulation is perturbed in disease.

Abdominal aortic calcification and the risk of bone fractures: a meta-analysis of prospective cohort studies

The relationship between abdominal aortic calcification (AAC) and bone fracture has been examined by some observational studies, but the results remain discordant. Therefore, we aimed to assess the link between them by conducting a meta-analysis of prospective studies. Relevant studies were identified by searching PubMed and EMBASE databases until the end of December 2016. Summary relative risks (RRs) and 95% confidence intervals (CIs) for associations between AAC and fracture risk were estimated with fixed- or random- effects models. Seven prospective studies were included in the final analysis. The summarized RRs of any type of fractures for the highest compared with the lowest category of AAC were 1.64 (95% CI 1.30-2.07, P = 0.000) with mild heterogeneity (I ² = 30.1%, P = 0.188). Subgroup analysis showed that the association between AAC and fracture was not significantly modified by gender and follow-up length. Risks were similar when analyses were restricted to the studies with adjustment for bone mineral density (BMD) (RR = 1.76, 95% CI 1.31-2.38, P = 0.000, I ² = 49.1%). For the specific type of fracture, severe AAC was significantly related with hip fracture (RR = 1.64, 95% CI 1.22-2.20, P = 0.001, n = 5), but not with vertebral (RR = 1.45, 95% CI 0.81-2.58, P = 0.213, n = 3) or non-vertebral fracture (RR = 1.35, 95% CI 0.96-1.88, P = 0.081, n = 3). There was no evidence of publication bias. Our findings demonstrated that AAC was significantly and independently associated with a higher fracture risk, especially for hip fracture.

Predicting Mortality in African Americans With Type 2 Diabetes Mellitus: Soluble Urokinase Plasminogen Activator Receptor, Coronary Artery Calcium, and High-Sensitivity C-Reactive Protein

BACKGROUND

Type 2 diabetes mellitus is a major risk factor for cardiovascular disease; however, outcomes in individual patients vary. Soluble urokinase plasminogen activator receptor (suPAR) is a bone marrow-derived signaling molecule associated with adverse cardiovascular and renal outcomes in many populations. We characterized the determinants of suPAR in African Americans with type 2 diabetes mellitus and assessed whether levels were useful for predicting mortality beyond clinical characteristics, coronary artery calcium (CAC), and high-sensitivity C-reactive protein (hs-CRP).

METHODS AND RESULTS

We measured plasma suPAR levels in 500 African Americans with type 2 diabetes mellitus enrolled in the African American-Diabetes Heart Study. We used Kaplan-Meier curves and Cox proportional hazards models adjusting for clinical characteristics, CAC, and hs-CRP to examine the association between suPAR and all-cause mortality. Last, we report the change in C-statistics comparing the additive values of suPAR, hs-CRP, and CAC to clinical models for prediction of mortality. The suPAR levels were independently associated with female sex, smoking, insulin use, decreased kidney function, albuminuria, and CAC. After a median 6.8-year follow-up, a total of 68 deaths (13.6%) were recorded. In a model incorporating suPAR, CAC, and hs-CRP, only suPAR was significantly associated with mortality (hazard ratio 2.66, 95% confidence interval 1.63-4.34). Addition of suPAR to a baseline clinical model significantly improved the C-statistic for all-cause death (Δ0.05, 95% confidence interval 0.01-0.10), whereas addition of CAC or hs-CRP did not.

CONCLUSIONS

In African Americans with type 2 diabetes mellitus, suPAR was strongly associated with mortality and improved risk discrimination metrics beyond traditional risk factors, CAC and hs-CRP. Studies addressing the clinical usefulness of measuring suPAR concentrations are warranted.

Fibroblast growth factor-23 in patients with homozygous familial hypercholesterolemia

BACKGROUND

Patients with homozygous familial hypercholesterolemia (HoFH) develop significant vascular calcification early in life, the cause of which is not yet fully understood. Patients with chronic kidney disease have similar vascular calcification, with fibroblast growth factor-23 (FGF23) implicated in these patients.

OBJECTIVE

To determine whether there was a difference in FGF23 between patients with HoFH and age- and gender-matched controls and whether there is a correlation between FGF23 and serum low-density lipoprotein, total cholesterol, and carotid intima-media thickness in patients with HoFH.

METHODS

The study was a cross-sectional review involving 30 patients with HoFH attending the Charlotte Maxeke Johannesburg Academic Hospital Lipid Clinic in Parktown, South Africa, as well as 30 age- and gender-matched healthy controls. FGF23, fasting lipid profiles, calcium, and phosphate were measured. B-mode ultrasonography of the carotid arteries was done to assess the extent and severity of arterial calcification.

RESULTS

There was no difference in mean FGF23 between the patient and control groups (62.07 ± 26.42 pg/mL vs 63.69 ± 19.84 pg/mL; P = .4621) nor was there any correlation between FGF23 and low-density lipoprotein cholesterol (P = .9483 and .8474) or total cholesterol (P = .9261 and .859). In the HoFH patients, FGF23 did not correlate significantly with any cardiovascular disease.

CONCLUSIONS

Serum FGF23 is not elevated in patients with HoFH when compared to non-familial hypercholesterolemia age- and gender-matched controls, and there is no correlation between serum FGF23 and cardiovascular disease in patients with HoFH. FGF23 does not appear to be a major factor for arterial calcification in HoFH.

FGF23 Concentration and APOL1 Genotype Are Novel Predictors of Mortality in African Americans With Type 2 Diabetes

OBJECTIVE

Cardiovascular and renal complications contribute to higher mortality in patients with diabetes. We assessed novel and conventional predictors of mortality in African American-Diabetes Heart Study (AA-DHS) participants.

RESEARCH DESIGN AND METHODS

Associations between mortality and subclinical atherosclerosis, urine albumin-to-creatinine ratio (UACR), estimated glomerular filtration rate (eGFR), plasma fibroblast growth factor 23 (FGF23) concentration, African ancestry proportion, and apolipoprotein L1 genotypes (APOL1) were assessed in 513 African Americans with type 2 diabetes; analyses were performed using Cox proportional hazards models.

RESULTS

At baseline, participants were 55.6% female with median (25th, 75th percentile) age 55 years (49.0, 62.0), diabetes duration 8 years (5.0, 13.0), glycosylated hemoglobin 60.7 mmol/mol (48.6, 76.0), eGFR 91.3 mL/min/1.73 m² (76.4, 111.3), UACR 12.5 mg/mmol (4.2, 51.2), and coronary artery calcium 28.5 mg Ca²⁺ (1.0, 348.6); 11.5% had two APOL1 renal-risk variants. After 6.6-year follow-up (5.8, 7.5), 54 deaths were recorded. Higher levels of coronary artery calcified plaque, carotid artery calcified plaque, albuminuria, and FGF23 were associated with higher mortality after adjustment for age, sex, and African ancestry proportion. A penalized Cox regression that included all covariates and predictors associated with mortality identified male sex (hazard ratio [HR] 4.17 [95% CI 1.96-9.09]), higher FGF23 (HR 2.10 [95% CI 1.59-2.78]), and absence of APOL1 renal-risk genotypes (HR 0.07 [95% CI 0.01-0.69]) as the strongest predictors of mortality.

CONCLUSIONS

Accounting for conventional risk factors, higher FGF23 concentrations and APOL1 non-renal-risk genotypes associated with higher mortality in African Americans with diabetes. These data add to growing evidence supporting FGF23 association with mortality; mechanisms whereby these novel predictors impact survival remain to be determined.

Long-Term Progression of Coronary Artery Calcification Is Independent of Classical Risk Factors, C-Reactive Protein, and Parathyroid Hormone in Renal Transplant Patients

Aims

Compared to the general population, mortality is significantly increased in renal transplant recipients. In the general population, coronary artery calcification (CAC) and its evolution over time are associated with cardiovascular and all-cause mortality, and the study of this biomarker could provide useful information for describing the long-term progression of coronary heart disease in renal transplant recipients.

Methods

We followed up a cohort of 113 renal transplant patients by performing three multi-detector computed tomography studies over 83.6 ± 6.8 months. Data analysis was performed by logistic regression analysis and by mixed linear modelling.

Results

Progression was observed in 34.5% of patients. Baseline CAC and time-to-transplantation were the sole variables that predicted CAC evolution over time. Neither classical nor nontraditional risk factors, biomarkers of renal function (GFR) and kidney damage (albuminuria) or biomarkers of bone mineral disorder (BMD), such as serum phosphorus, calcium, and PTH, were associated with the long-term progression of coronary calcification. Serum triglycerides predicted CAC progression only in logistic regression analysis, while in addition to baseline CAC, time to transplantation was the sole variable predicting CAC progression when the data were analyzed by mixed linear modelling. These data suggested that, in addition to the background calcification burden, other unmeasured factors play major roles in promoting the evolution of coronary calcification in the transplant population.

Conclusion

CAC progression continued over the long-term follow-up of renal transplant patients. This phenomenon was unaccounted for by classical and nontraditional risk factors, as well as by biomarkers of renal dysfunction and renal damage.

Elevated serum fibroblast growth factor 23 levels as an indicator of lower extremity atherosclerotic disease in Chinese patients with type 2 diabetes mellitus

Background

Recently, basic and clinical studies have provided evidence supporting the relationship between circulating levels of fibroblast growth factor (FGF) 23 and the development of atherosclerosis. Given that diabetes is an established risk factor for lower extremity atherosclerotic disease (LEAD), the goal of the present study was to explore the relationship between serum FGF23 levels and LEAD, as well as the related factors, in Chinese patients with type 2 diabetes mellitus (T2DM).

Methods

A total of 401 hospitalized T2DM patients (201 subjects with LEAD and 200 subjects without LEAD) were enrolled in this study. Serum FGF23 levels were determined by a sandwich enzyme-linked immunosorbent assay. Femoral intima-media thickness (F-IMT) and lower limb atherosclerotic plaque were assessed through color Doppler ultrasound.

Results

The median (interquartile range) serum FGF23 levels in the entire study population was 42.08 (35.59–49.17) pg/mL. Subjects with LEAD had significantly higher serum FGF23 levels compared with those without LEAD (44.00 [37.54–51.30] pg/mL versus 40.42 [32.61–48.23] pg/mL, P < 0.001). Logistic regression showed that serum FGF23 levels were independently and positively correlated with the presence of LEAD (odds ratio 1.039, 95% confidence interval 1.012–1.067, P = 0.004). In addition, multiple liner regression analysis revealed that serum FGF23 levels were positively associated with F-IMT (standardized β = 0.175, P < 0.001). Furthermore, this relationship remained significant after additional adjustment for gender and factors potentially affecting serum FGF23 levels (serum calcium, serum phosphorus, and glomerular filtration rate), respectively (both P < 0.01).

Conclusions

In Chinese patients with T2DM, serum FGF23 levels were independently and positively correlated with the presence of LEAD.

FGF-23 and cardiovascular disease: review of literature

PURPOSE OF REVIEW

This review examines associations between fibroblast growth factor 23 (FGF-23) and cardiovascular disease.

RECENT FINDINGS

FGF-23 is a hormone produced by osteocytes and osteoblasts that aids with phosphate excretion by the kidney and acts as a negative feedback regulator for activated vitamin D synthesis. Recent studies have found associations between elevated FGF-23 levels and a number of cardiovascular diseases, including hypertension, left ventricular hypertrophy, endothelial dysfunction, cardiovascular events and mortality.

CONCLUSION

Recent studies have explored the possible effects of FGF-23 on the cardiovascular system. In animal and observational human studies, there is a link between elevated FGF-23 levels and multiple cardiovascular outcomes, including hypertension, left ventricular hypertrophy and cardiovascular events and mortality. Further studies are required to evaluate whether decreasing FGF-23 levels improves cardiovascular outcomes.

Pathology of Human Coronary and Carotid Artery Atherosclerosis and Vascular Calcification in Diabetes Mellitus

The continuing increase in the prevalence of diabetes mellitus in the general population is predicted to result in a higher incidence of cardiovascular disease. Although the mechanisms of diabetes mellitus-associated progression of atherosclerosis are not fully understood, at clinical and pathological levels, there is an appreciation of increased disease burden and higher levels of arterial calcification in these subjects. Plaques within the coronary arteries of patients with diabetes mellitus generally exhibit larger necrotic cores and significantly greater inflammation consisting mainly of macrophages and T lymphocytes relative to patients without diabetes mellitus. Moreover, there is a higher incidence of healed plaque ruptures and positive remodeling in hearts from subjects with type 1 diabetes mellitus and type 2 diabetes mellitus, suggesting a more active atherogenic process. Lesion calcification in the coronary, carotid, and other arterial beds is also more extensive. Although the role of coronary artery calcification in identifying cardiovascular disease and predicting its outcome is undeniable, our understanding of how key hormonal and physiological alterations associated with diabetes mellitus such as insulin resistance and hyperglycemia influence the process of vascular calcification continues to grow. Important drivers of atherosclerotic calcification in diabetes mellitus include oxidative stress, endothelial dysfunction, alterations in mineral metabolism, increased inflammatory cytokine production, and release of osteoprogenitor cells from the marrow into the circulation. Our review will focus on the pathophysiology of type 1 diabetes mellitus- and type 2 diabetes mellitus-associated vascular disease with particular focus on coronary and carotid atherosclerotic calcification.

TBS Predict Coronary Artery Calcification in Adults

Purpose. This study analyzes the association between the bony microarchitecture score (trabecular bone score, TBS) and coronary artery calcification (CAC) in adults undergoing health exams. Materials and Methods. We retrospectively collected subjects (N = 81) who underwent coronary computed tomography and bone mineral density studies simultaneously. CAC was categorized to three levels (Group 0, G0, no CAC, score = 0, N = 45; Group 1, G1, moderate CAC, score = 1–100, N = 17; Group 2, G2, high CAC, score ≧ 101, N = 19). Multinomial logistic regression was used to study the association between TBS and CAC levels. Results. CAC is present in 44.4% of the population. Mean TBS ± SD was 1.399 ± 0.090. Per 1 SD increase in TBS, the unadjusted odds ratio (2.393) of moderate CAC compared with no CAC was significantly increased (95% CI, 1.219–4.696, p = 0.011). However, there has been no association of TBS with high CAC (OR: 1.026, 95% CI: 0.586–1.797, p = 0.928). These relationships also existed when individually adjusted for age, sex, and multiple other covariates. Conclusions. Higher TBS was related to moderate CAC, but not high CAC; a possible explanation may be that bone microarchitecture remodeling becomes more active when early coronary artery calcification occurs. However, further researches are needed to clarify this pathophysiology.