Cancer as a risk factor for physical dysfunction and poor prognosis in patients with cardiovascular disease

Introduction

The emerging interdisciplinary field of cardio-oncology is of interest to clinicians because a history of cancer or cancer treatment is considered a severe risk factor for cardiovascular disease (CVD). Both cancer and CVD can reduce skeletal muscle mass; together, they can lead to a poorer prognosis. However, it is unclear whether a patient's cancer history can lower physical function and lead to a poor prognosis with the coexistence of cancer history and physical dysfunction in patients with CVD. This study aimed to identify the relationship between cancer history and physical function, as well as the prognostic value of their combination, in patients with CVD.

Methods

We reviewed 3,640 patients with CVD (mean age, 67.9±13.5 years) who underwent physical-function tests (gait speed and 6-min walking distance [6MWD]). We performed multivariate linear regression analysis to assess potential associations between cancer history and physical-function tests in patients with CVD. Additionally, we used the Kaplan–Meier curve and Cox regression analyses to assess survival and prognostic significance for patients divided into four groups according to the presence or absence of cancer history and high or low physical function.

Results

In multivariate linear regression analysis, cancer history was independently associated with lower gait speed and 6MWD (gait speed, P=0.048 and 6MWD, P=0.040). A total of 581 deaths occurred over a median follow-up period of 3.08 years (interquartile range: 1.36–5.27). For all-cause mortality, patients with a history of cancer and reduced physical function were found to have a significantly higher mortality risk even after adjusting for several covariates (gait speed, HR: 1.66, P=0.003 and 6MWD, HR: 1.71, P=0.003).

Conclusion

Cancer history was correlated with physical dysfunction in patients with CVD. Moreover, the coexistence of cancer history and physical dysfunction resulted in poorer prognosis in patients with CVD.

Funding Acknowledgement

Type of funding sources: None.

O-064 Recovery culture of human cryopreserved blastocysts with prolactin after warming improves trophoblast outgrowth

Study question

Does prolactin (PRL) treatment during recovery culture affect human blastocyst outgrowth?

Summary answer

PRL treatment for 120 min promoted trophoblast outgrowth in cryopreserved human blastocysts by upregulating the expressions of epithelial-to-mesenchymal transition (EMT) and focal adhesion-related genes.

What is known already

Human embryos express the PRL receptor at the morula and the blastocyst stages. This expression correlates with the blastocyst diameter and the time required for the embryos to reach the blastocyst stage. Treatment with PRL from cleavage to the blastocyst stage improves blastocyst outgrowth to fibronectin. However, whether PRL treatment after warming cryopreserved blastocysts cultured to the blastocyst stage without PRL influences outgrowth competence remains unknown. Furthermore, the optimal time for post-warming PRL treatment remains to be ascertained.

Study design, size, duration

A total of 374 discarded human vitrified blastocysts donated for research by consenting couples were used. The study was approved by the Institutional Review Board. The blastocysts were randomly allocated to two groups, to be cultured in medium either with PRL (n = 208) or without PRL (control; n = 166). The gene expression level, blastocyst adhesion, outgrowth area, and distance of trophoblast migration were compared between the groups.

Participants/materials, setting, methods

Vitrified human blastocysts were cultured for 120 min after warming. Some blastocysts were treated with PRL for 15–120 min during the recovery period. The blastocysts were plated on fibronectin-coated dishes and cultured to assess blastocyst adhesion and outgrowth. The expressions of PRL-interacting genes were assessed by quantitative RT-PCR 12 h after outgrowth culture. The migration distance at the outer edge of the trophoblast cells was examined using time-lapse systems.

Main results and the role of chance

The mRNA expressions of ezrin, radixin, and moesin, which regulate cell adhesion and invasion by controlling actin reorganisation during EMT, was stimulated by PRL treatment for 120 min. The expressions of EMT-related genes, transforming growth factor β1, snail1, and twist1 were also promoted by treatment with PRL for 120 min. The blastocysts treated with PRL also exhibited augmented expression of cadherin2 and transcriptional repression of cadherin1. Higher mRNA expressions of integrin-based focal adhesion-related genes, ITGA5 and ITGB1, were observed after treatment with PRL for 120 min compared to that in the other groups. PRL treatment for 120 min did not alter the rate of blastocyst adhesion to fibronectin-coated dishes 96 h after the outgrowth culture assay. However, multiple linear regression analysis revealed that the outgrowth area was significantly increased in blastocysts treated with PRL. The migration distance of trophoblast cells was significantly increased after PRL treatment. Furthermore, a more beneficial effect of prolactin treatment on blastocyst outgrowth was observed when the blastocysts were vitrified on day 5 compared to that when the blastocysts were vitrified on day 6. Moreover, the outgrowth area was increased by PRL treatment when the blastocyst diameter was larger than 180 µm.

Limitations, reasons for caution

The results may vary between in vivo and in vitro conditions. Further clinical studies are required to explore the clinical efficacy of PRL treatment.

Wider implications of the findings

This study showed that PRL treatment for 120 min improved trophoblast migration in cryopreserved human blastocysts. Therefore, recovery culture with PRL treatment post-warming followed by blastocyst transfer could improve pregnancy outcomes.

Trial registration number

not applicable

P-152 The first morphokinetic map of human abnormal fertilisation

Study question

What are the similarities and differences between the morphokinetics of abnormal, one- (1PN) and three-pronuclear (3PN) and normal bi-pronuclear (2PN) fertilisation?

Summary answer

The morphokinetic analysis of 1PN/3PN fertilisation reveals novel aspects of abnormal early development.

What is known already

Assisted reproduction technology has allowed the observation of early human development. Initially assessed statically at a single time point, fertilization has revealed its complexity once observed by Time-Lapse Microscopy (TLM). Detailed morphokinetic analysis of fertilisation has been reported in the last few years, unveiling previously unknown cytoplasmic phenomena (e.g. the cytoplasmic wave and halo) and the importance of cell symmetry for embryo development. At present, abnormal fertilization remains neglected, despite potential for understanding the physiology and pathology of early human development.

Study design, size, duration

This retrospective study involved TLM observation of normally (2PN, n = 2,685) and abnormally (1PN, n = 41; 3PN, n = 127) fertilised oocytes generated in ICSI cycles. Oocyte retrievals were carried out after the clomiphene citrate-based minimal ovarian stimulation, between October 2019 and December 2020. Oocytes of patients with different diagnoses of infertility were included in the analysis, while cases involving cryopreserved gametes or surgically retrieved sperm were excluded.

Participants/materials, setting, methods

Microinjected oocytes were assessed by a combined TLM-culture system (Embryoscope). Oocytes not suitable for TLM assessment, due to excess of residual corona cells or inadequate orientation for correct observation, were not analysed. Phenomena, relevant to meiotic resumption, pronuclear dynamics, cytoplasmic/cortical modifications, cleavage pattern, and embryo quality, were annotated and compared between groups.

Main results and the role of chance

Second polar body (PBII) extrusion was observed in all 1PN- and in a majority of 3PN-zygotes (92.1%). A 0.3-hour delay in PBII extrusion was confirmed in 3PN-zygotes (P = 0.0439). In a significant proportion of 3PN-zygotes, a third (female) PN formed from reabsorption of the PBII. The cytoplasmic wave was observed not only in 2PN- and 3PN-, but also in 1PN-zygotes. The presence and position of cytoplasmic halo were comparable among the three classes of zygotes. However, the duration of the cytoplasmic halo was prolonged in 1PN-zygotes (P < 0.0001). PN juxtaposition immediately before PN breakdown was less frequent in 3PN- compared with 2PN-zygotes (P = 0.0159). Furthermore, asynchronous PN breakdown was increased in 3PN- compared with 2PN-zygotes (P = 0.0026). The PN area of 1PN- was larger than that of 2PN-zygotes; however, the PN area of 3PN-zygotes was smaller than that of 2PN-zygotes. In 1PN-zygotes, a developmental delay was observed starting from the disappearance of the cytoplasmic halo, reaching 9 hours at the time of cleavage (P < 0.0001). A higher incidence of abnormal cleavage (P = 0.0019) and blastomere fragmentation (P < 0.0001) was observed in 1PN-zygotes. Cleavage progression was increasingly affected especially in 1PN-zygotes, resulting in blastocyst formation rates of 70.2%, 12.2% and 53.5% in 2PN-, 1PN- and 3PN-zygotes, respectively (P < 0.0001).

Limitations, reasons for caution

The study data derive from treatments carried out in a single centre. The study findings therefore require independent verification from other research groups.

Wider implications of the findings

These observations suggest that 1PN and 3PN fertilisation follow the general pattern of normal fertilization. Crucially, they also shed light on diverse and previously undescribed phenomena - e.g. reabsorption of the PBII in 3PN zygotes - underpinning the origins of abnormal fertilization and potentially clinically relevant.

Trial registration number

not applicable

Is GLP-1 insufficiency a coronary risk factor? A multicenter observational study, BOREAS-CAD2

Background and aim

Glucagon-like peptide-1 (GLP-1) regulates insulin secretion and also affords pleiotropic effects including protective effects on blood vessels. Multiple factors regulate GLP-1 secretion after meals, but a group of apparently healthy subjects showed blunted responses of GLP-1 secretion in our previous study. In this study, we examined the possibility that the reduced capacity of GLP-1 secretion is associated with increased extent of coronary artery stenosis in non-diabetic patients.

Methods and results

Non-diabetic patients who were admitted for coronary angiography without a history of coronary interventions were enrolled. Coronary artery stenosis was quantified by Gensini score (GS), and GS ≥10 was used as an outcome variable based on results of earlier studies indicating its predictive value for cardiovascular events. The patients (mean age, 66.5±8.8 years; 71% males, n=173) underwent oral 75 g-glucose tolerant tests for determination of glucose, insulin and active GLP-1 levels. The area under the curve of plasma active GLP-1 (AUC-GLP-1) was determined as an index of GLP-1 secretion capacity. AUC-GLP-1 was not correlated with fasting glucose, AUC-glucose, serum lipids, indices of insulin sensitivity or estimated glomerular filtration rate. In multivariate logistic regression analysis for GS ≥10, AUC-GLP-1 < median, age and hypertension were selected as explanatory variables, though fasting GLP-1 level was not selected.

Conclusion

The findings indicate significant association of reduced GLP-1 secretion capacity with increased extent of coronary artery stenosis in non-diabetic patients. A causal relationship between change in GLP-1 secretion capacity and coronary stenosis remains to be examined by a longitudinal study

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): This study was supported in part by a research grant from Investigator-Initiated Studies Program of Merck Sharp & Dohme Corp./MSD K.K.

Combination of CHARGE AF score and index of 24-hour electrocardiogram to predict incident atrial fibrillation and cardiovascular events

Background

Atrial fibrillation (AF) is associated with increased risks of stroke and heart failure. AF risk prediction can facilitate the efficient deployment of diagnosis or interventions to prevent AF.

Purpose

We sought to assess the combination prediction value of Holter electrocardiogram (Holter ECG) and the CHARGE-AF score (Cohorts for Aging and Research in Genomic Epidemiology-AF) for the new-onset of AF in a single center study. We also investigated the association between clinical findings and the new-onset of cerebral cardiovascular events.

Methods

From January 2008 and May 2014, 1246 patients with aged≥20 undergoing Holter ECG for palpitations, dizziness, or syncope were recruited. Among them, 350 patients were enrolled in this study after exclusion of 1) AF history at the time of inspection or before, 2) post cardiac device implantation, 3) follow-up duration <1 year, and 4) no 12-lead ECG records within 6 months around Holter ECG.

Results

During the 5.9-year follow-up, 40 patients (11.4%) developed AF incidence. Multivariate cox regression analysis revealed that CHARGE-AF score (hazard ratio [HR]: 1.59, 95% confidence interval (95% CI): 1.13–2.26, P<0.01), BMI (HR: 0.91, 95% CI: 0.83–0.99, P=0.03), frequent supraventricular extrasystoles (SVEs) ≥1000 beats/day (HR: 4.87, 95% CI: 2.59–9.13, P<0.001) and first-degree AV block (HR: 3.52, 95% CI: 1.63–7.61, P<0.01) were significant independent predictors for newly AF. The area under the ROC curve (AUC) of the combination of the CHARGE-AF score and frequent SVEs (≥1000) was greater than the CHARGE-AF score alone (0.73, 95% CI: 0.64–0.82 vs 0.66, 95% CI: 0.56–0.75, respectively). On the ROC curve, the CHARGE-AF score of 12.9 was optimum cut-off value for newly AF. Patients with both the CHARGE-AF score≥12.9 and SVEs≥1000 developed AF at 129.0/1000 person-years, compared with those with the CHARGE-AF score<12.9 and SVEs≥1000 (48.9), the CHARGE-AF score≥12.9 and SVEs<1000 (40.0) and the CHARGE-AF score<12.9 and SVEs<1000 (7.4), respectively. In multivariate cox regression analysis, age, past history of congestive heart failure and myocardial infarction, and antihypertensive medication were significant predictors of cerebral cardiovascular events (n=43), all of which signifying the components of the CHARGE-AF score. The AUC of the combination of the CHARGE-AF score and frequent SVEs (≥1000) was not different from the CHARGE-AF score alone (0.73, 95% CI: 0.64–0.81 vs 0.73, 95% CI: 0.64–0.82, respectively).

Conclusion

CHARGE-AF score has higher predictive power of both the new incident AF and cerebral cardiovascular events. The combination of CHARGE-AF score and SVEs≥1000 beats/day in Holter ECG can demonstrate the additional effect of prediction ability for the new incident AF, but not for cerebral cardiovascular events.

Funding Acknowledgement

Type of funding sources: None.

O-223 Fatty acid supplementation into warming solutions improve the developmental competence of mouse, bovine, and human oocytes and embryos after vitrification

Study question

Does fatty acid (FA) supplementation into vitrification and warming solutions influence the developmental competence of oocyte and embryo after vitrification and warming?

Summary answer

FA supplementation during the warming process improves the developmental competence of vitrified-warmed mouse oocytes and embryonic-morphologies after vitrification at the cleavage-stage in bovines and humans.

What is known already

Vitrified metaphase II stage oocytes exhibit a diminished ability to develop into blastocysts and live births. Previous studies have shown reduction in intracellular lipid content as one of the factors associated with reduced developmental competence of oocytes after vitrification as the intracellular lipid content of oocytes is affected by vitrification. FAs derived from break down of lipids are primarily transferred to the mitochondria, where it plays a crucial role in cellular metabolism. However, the effects of FA supplementation in warming solutions on the cytoplasmic lipid content and subsequent embryo development are unknown.

Study design, size, duration

A chemically defined FA mixture was added to the vitrification and/or warming solutions. Oocytes collected from C57BL6/N (n = 80) were randomly divided into three groups (fresh, n = 634; non-FA (control), n = 961; FA, n = 1,686), and were vitrified-warmed with/without FA. Lipid composition, developmental competence, and gene expression levels were compared among the groups. Bovine embryos (fresh, n = 420; control, n = 524; FA, n = 492) and discarded human day-2 embryos (control, n = 87; FA, n = 92) were used to examine the developmental competence of embryos.

Participants/materials, setting, methods

Lipids in the ooplasm were stained with Nile red and the fluorescence intensity was analysed. The developmental competence of mouse oocytes was examined by performing intracytoplasmic sperm injection. Expressions of FA metabolism-related genes were measured. The bovine embryos were vitrified at the four-cell stage and cultured to the blastocyst stage after warming. Cryopreserved discarded human embryos were warmed and cultured. The obtained blastocysts were then placed on fibronectin-coated dishes to examine the outgrowth formation.

Main results and the role of chance

Lipid content of mouse oocytes was significantly lower in the control group compared to that in the fresh group (P < 0.05). On the contrary, lipid contents of FA and fresh groups were comparable (P = 0.24). Blastocyst formation rate was significantly higher in the FA group than that in the control group (55.7% and 44.8%, respectively; P < 0.05). To examine the optimal timing for FA supplementation, FA was added to the vitrification solution (FAvit), warming solution (FAthaw), and/or both solutions (FAvit-thaw). Blastocyst formation rate was significantly higher in the FAthaw group than that in the control group (59.8% and 50.0%, respectively; P < 0.05). The mRNA expressions of Acaa2 and Hadha in mouse embryos were significantly higher in the FAthaw group compared to that in the control group (P < 0.05). Moreover, FA supplemented warming solutions significantly improved the blastocyst formation rate in bovines (control, 53.5%; FAthaw, 64.5%; P < 0.05). Developmental rate to the expanded blastocyst stage was slightly improved in human embryos (control, 53.7%; FAthaw, 63%; P = 0.38) and the proportion of Grade A in inner cell mass and trophectoderm was significantly higher in the FAthaw group than that in the control group (P < 0.05). There were no differences in the outgrowth abilities between the control and FAthaw groups.

Limitations, reasons for caution

Since the experiments of the current study on human embryos were performed in vitro using discarded embryos, in vivo developmental ability was not evaluated. Therefore, to validate the application of our findings in human assisted reproductive technologies, further clinical trials (ART) are warranted.

Wider implications of the findings

FA supplementation into the warming solutions improved the developmental competence of vitrified–warmed oocytes and cleaved embryos by activating the β-oxidation pathway. These results indicate that FA supplementation into warming solutions is a potential strategy to improve clinical outcomes in human ART.

Trial registration number

not applicable

Triglyceride to HDL-cholesterol ratio is a predictor of future coronary events: a possible role of high-risk coronary plaques detected by coronary CT angiography

Background

For the prevention of future cardiovascular events, control of residual risks such as triglyceride rich lipoproteins and HDL-cholesterol is an emerging problem beyond LDL-cholesterol. Triglyceride to HDL-cholesterol ratio (TG/HDL ratio) has been reported to be useful for risk classification of cardiovascular diseases. Meanwhile, several studies showed that high-risk plaque characteristics evaluated with coronary CT angiography (cCTA) was associated with the incidence of acute coronary syndrome. However, the relationship of TG/HDL ratio with coronary plaque characteristics and its impact of this association on future coronary events have not been fully elucidated.

Purpose

The aim of this study was to evaluate the association between TG/HDL ratio and high-risk plaque detected by cCTA and its impact on future coronary events.

Methods

A total of 944 patients suspected stable coronary artery disease who underwent cCTA at our institution were analyzed (mean 64-year-old, 55% male). Patients were divided into two groups by the median value of TG/HDL ratio (higher TG/HDL: TG/HDL ratio ≥2.0, lower TG/HDL: TG/HDL ratio <2.0). Coronary high-risk plaques were defined as a plaque with all three components; low attenuation plaque (<50H.U.), positive remodeling (remodeling index >1.1) and spotty calcification. Cardiovascular event was defined as cardiovascular death, acute coronary syndrome, and late coronary revascularization after 30 days of CT acquisition.

Results

The higher TG/HDL ratio was significantly associated with male gender (63% vs. 48%, P<0.001), body mass index (24.8±3.8 vs. 22.9±4.0, p<0.001), the prevalence of hypertension (65% vs. 54%, P<0.001), dyslipidemia (60% vs. 42%, P<0.001), diabetes mellitus (38% vs. 27%, P=0.001) and current smoking (26% vs. 10%, p<0.001). Regarding cCTA findings, the prevalence of significant stenosis, calcified plaque, non-calcified plaque, coronary plaques with low attenuation plaque, positive remodeling and spotty calcification in the higher TG/HDL group were greater than those in the lower group (Figure 1A). Of note, the difference in high-risk plaque between two groups was significant. (18% vs. 11%, p=0.004). Multivariate logistic analysis revealed that the TG/HDL ratio was an independent risk factor for high-risk plaque even after adjustment (OR, 1.35; 95% CI, 1.01–1.81; p=0.049). Regarding coronary events (median follow-up duration; 48 months), Kaplan-Meier curve showed poor event-free rate in the higher TG/HDL group (Figure 1B). At Cox proportional hazard analysis, higher TG/HDL ratio (HR, 1.94; 95% CI, 1.01–3.70; p=0.046) and CT-verified high-risk plaque (HR, 2.36; 95% CI, 1.27–4.38; p=0.006) were independent predictive factors for coronary events even after adjustment.

Conclusion

TG/HDL ratio is involved in the vulnerability of CT-verified coronary plaque characteristics. This association may play an important role in the prognostic impact of TG/HDL ratio on future cardiovascular events.

Funding Acknowledgement

Type of funding source: None

Evaluation of new-onset atrial fibrillation using continuous patch monitor in patients undergoing transcatheter aortic valve replacement

Background

Transcatheter aortic valve replacement (TAVR) has emerged as an important therapeutic option among intermediate- and high-risk patients with symptomatic severe aortic stenosis. Heart rhythm disorders frequently complicate TAVR, particularly atrial fibrillation (AF), which can affect >40% patients undergoing the procedure. There is wide variation in rates of new-onset AF (NOAF) following TAVR across the initial pivotal randomized trials and observational studies, but burden of AF in each patient is not well known. The aim of this study is to evaluate AF burden detected by continuous patch ECG monitor (WR-100; Fukuda-Denshi, Tokyo,Japan) in patients after TAVR.

Method

Among KPUM-TAVR cohort, 58 consecutive patients (mean age:85.5±5.5, 44 females) kept recording continuous patch ECG monitor for 14 days after the procedure of TAVR. We excluded 11 patients with ECG indicating AF before procedure (paroxysmal AF 5, persistent AF 6). Finally, 47 eligible patients were selected according to the study criteria. AF was defined as a presence of AF more than 30sec on ECG monitor. The incidence and burden of NOAF was assessed.

Results

We identified 9 of 47 patients (19.1%) who developed NOAF (94% of transfemoral access patients, 6% of non- transfemoral access patients). Patients developing NOAF and had higher Society of Thoracic Surgeons risk scores (5.9±3.8 vs 9.9±6.3 p=0.0187). AF was first observed from day1 to day13. Despite having a median CHA2DS2-VASc score of 5 (25th and 75th percentile: 5 to 6), only 33% of patients with NOAF were given oral anticoagulation during the follow-up.

Conclusion

By using continuous patch ECG monitor, NOAF can be identified in 19.1% of patients after TAVR, with wide variety of first onset of AF. Given the clinical significance of post-TAVR AF, additional studies are necessary to describe the optimal management strategy in this high-risk population.

Figure 1

Funding Acknowledgement

Type of funding source: None

P207 Synergetic effect of amino acid and ketone metabolism underlies empagliflozin-mediated cardioprotection in the type 2 diabetic heart

Funding Acknowledgements

Boehringer Ingelheim

Background

 Although emerging evidence has indicated that sodium glucose cotransporter 2 (SGLT2) inhibitors restore impaired cardiac energetics in type 2 diabetes mellitus (T2DM), the underlying molecular mechanisms have yet to be established.  Augmented utilization of ketone is one proposed hypothesis, but depletion of succinyl-CoA triggered by the conversion of ketone back to acetyl-CoA by SCOT (succinyl-CoA:3-oxoacid CoA transferase) may hamper oxidative capacity of the tricarboxylic acid (TCA) cycle, which also requires succinyl-CoA.  The recent finding that empagliflozin augments systemic amino acid metabolism in patients with T2DM led us to hypothesize that the anaplerotic effect of amino acid on the TCA cycle complements ketone oxidation.

Methods and Results

 Myocardial infarction (MI) was induced in T2DM rats (OLETF) and control rats (LETO).  Survival rate at 48 hours after MI was significantly lower in OLETF than in LETO (40% vs 84%), and empagliflozin treatment (10 mg/kg/day, 14 days) before MI improved the survival rate in OLETF to 70%.  Metabolome analysis was performed using heart tissues from the non-infarct region 12 hours after MI.  Using principal component analysis, data from 92 metabolites that were detected were compressed into 2 dimensions, and the first component (PC1) clearly separated empagliflozin-treated OLETF from non-treated LETO and OLETF.  Analysis of factor loading of each metabolite for PC1 revealed that branched chain amino acids leucine, isoleucine and valine, the latter two of which can be oxidized to succynyl-CoA, and β-hydroxybutyrate were the top four metabolites that characterized empagliflozin treatment.  Furthermore, in comparison to LETO, OLETF treated with empagliflozin showed 50% higher levels of glutamine and glutamate, both of which can replenish the TCA cycle at the level of α-ketoglutarate.  In OLETF, empagliflozin significantly increased the TCA cycle intermediates citrate, cis-aconitate and malate by 74%, 119% and 59%, respectively.  OLETF showed 86% higher lactate and 38% lower ATP than those in LETO, but levels of the metabolites were normalized by empagliflozin, suggesting improved glucose oxidation.

Conclusions

  The present analyses showed that amino acid and ketone metabolism are metabolic pathways that are most affected by empagliflozin.  Coordination of these "starvation-induced pathways" may underlie the favorable metabolic effect of empagliflozin in T2DM hearts.

P121 Pressure overload-induced functional and metabolic impairments in type 2 diabetic hearts are ameliorated by inhibition of xanthine oxidase

Funding Acknowledgements

SANWA KAGAKU KENKYUSHO Co., Ltd.

Background

  We have recently demonstrated that AMP deaminase (AMPD) is upregulated in OLETF, obese type 2 diabetic (T2DM) rats, and that the upregulated AMPD contributes to depletion of myocardial ATP at the time of pressure overload, leading to diastolic dysfunction.  On the other hand, AMPD promotes the formation of IMP from AMP, and IMP is in turn further converted to hypoxanthine and xanthine, substrates of xanthine oxidase (XO), which produces uric acid with ROS as a byproduct.  Based on these findings, we tested the hypothesis that inhibition of XO ameliorates the pressure overload-induced diastolic dysfunction in T2DM rats. 

Methods and results

Metabolomic analyses of the left ventricular myocardium revealed that levels of myocardial hypoxanthine and xanthine were significantly higher by 30% and 28%, respectively, in OLETF than in LETO, non-diabetic control rats, under the condition of pressure overloading (200-230 mmHg) induced by phenylephrine infusion. Myocardial XO activity in OLETF was 57.9% higher than that in LETO, and the activity was significantly attenuated by oral administration of topiroxostat, an XO inhibitor, at 0.1-0.5 mg/kg/day for 14 days in a dose-dependent manner.  Pressure volume loop analyses showed that the pressure overloading induced by phenylephrine infusion resulted in significantly higher LVEDP in OLETF than in LETO (18.3 ± 1.5 vs. 12.2 ± 1.3 mmHg, p < 0.05, n = 7), though LVEDPs at baseline were comparable in OLETF and LETO (5.6 ± 0.4 vs. 4.7 ± 0.7 mmHg).  Treatment with topiroxostat significantly suppressed the pressure overload-induced elevation of LVEDP in OLETF (18.3 ± 1.5 vs. 11.3 ± 1.1 mmHg, p < 0.05) but not in LETO.  Tau, the time constant of LV pressure decay, was significantly prolonged to 14.7 ± 0.7 ms (p < 0.05) by pressure overloading in OLETF but not in LETO, though baseline Tau values were similar in LETO and OLETF (6.1 ± 0.2 vs. 8.0 ± 0.4 ms).  The prolongation of Tau by pressure overloading in OLETF was significantly attenuated by treatment with topiroxostat.  Ea/Ees, an index for ventricular-arterial coupling, was higher in OLETF than in LETO (2.3 ± 0.3 vs. 1.6 ± 0.3, p < 0.05) under the condition of pressure overloading, and it was also improved by topiroxostat in OLETF (1.2 ± 0.2, p < 0.05).  Myocardial ATP content was lower in OLETF than in LETO under the condition of pressure overloading (2966 ± 400 vs. 1818 ± 171 nmol/g wet tissue, p < 0.05), but treatment with topiroxostat significantly restored the ATP level (2629 ± 307 nmo/g wet tissue). Conclusion:  In T2DM hearts, not only XO activity but also XO substrates are upregulated and upregulated AMPD may be involved in the upregulation.  Inhibition of XO ameliorates pressure overload-induced diastolic dysfunction and improves ventricular-arterial coupling most likely through augmented ATP preservation.

P5305Oxidized high-density lipoprotein is associated with progression of coronary artery calcification

Introduction

As a residual cardiovascular risk, high-density lipoprotein (HDL) is of great interest in lipid management. Native HDL has an anti-atherogenic role, while oxidized HDL (oxHDL) has atherogenic property because of reduced anti-inflammatory properties compared with native HDL. Meanwhile, recent studies showed that rapid progression of coronary artery calcification (CAC), a marker of subclinical atherosclerosis, was associated with greater incidence of cardiovascular events. However, the role of oxHDL in the pathogenesis of CAC remains unclear.

Purpose

The purpose of this study was to examine the association between the annual change in oxHDL and the progression of CAC (Agatston score) in a substudy of prospective multicenter randomized study.

Methods

In the principal study, patients with a CAC score of 1 to 999 were treated with pitavastatin with/without eicosapentaenoic acid. Measurement of CAC with MDCT and a blood test were performed at baseline and at the 1-year follow-up. The principal study showed 30–40% of annual change in CAC in all patients and no difference in the progression of CAC among treatment groups. In this substudy (n=140), patients were divided into 2 groups: CAC progression (change in Agatston score of >0, n=103) and no CAC progression (n=37). The serum concentration of oxHDL was measured using an antibody against oxidized human apoA-I with ELISA. The difference in oxHDL between patients with hypercholesterolemia and healthy subjects (n=30) was also evaluated.

Results

OxHDL levels were significantly lower in healthy subjects than in patients with hypercholesterolemia (150 [107–176] and 167 [132–246], respectively; median [25th-75th percentile], U/ml) (p=0.006). The baseline log-transformed oxHDL level was correlated with total cholesterol (r=0.21, p=0.01), HDL-cholesterol (r=0.33, p<0.01), and triglycerides (r=−0.21, p=0.01), but not correlated with age, body mass index, hemoglobinA1c, LDL-cholesterol, serum creatinine, or high-sensitivity C-reactive protein. After treatment, the oxHDL level significantly decreased from 167 (132–246) at baseline to 122 (103–149) (median [25th–75th percentile], U/ml) (p<0.001). The annual change in CAC was significantly positively associated with changes in oxHDL (r=0.17, p=0.04), triglycerides (r=0.17, p=0.04), and hsCRP (r=0.22, p=0.01) but not associated with changes in LDL-C or HDL-C. Multiple logistic analysis demonstrated that the decrease in oxHDL per 10 U/ml was independently associated with CAC progression after adjusting for variables including baseline oxHDL, LDL-cholesterol, Agatston score and current smoking (odds ratio, 0.95; 95% confidence interval, 0.90–0.99; p=0.04).

Conclusion

The decrease in oxHDL is associated with the attenuation of CAC progression, suggesting that oxHDL is a potential target for preventing atherosclerosis.

P692Chemoradiation therapy to patients with lung cancer exacerbates thoracic aortic calcification

Introduction

Development of chemoradiation therapy (CRT) has improved mortality in patients with cancer. Whereas, it is emerging problem that cancer-survivors suffer from cardiovascular diseases, and the association between modern CRT and the increase in future cardiovascular events is suggested. Meanwhile, previous studies showed that thoracic aortic calcification (TAC) detected by computed tomography (CT), a marker of atherosclerosis, was associated with all-cause mortality and cardiovascular events. However, the influence of CRT on TAC progression remains unclear.

Purpose

The purpose of this study was to evaluate whether CRT would exacerbate TAC.

Methods

A total of 68 patients who treated lung cancer at our hospital between 2011 and 2015 were retrospectively analyzed (mean 62 year-old, male 78%): 35 patients underwent surgical treatment after induction CRT (CRT group) and 33 patients underwent surgical treatment alone (control group), extracted by propensity score matching by age, sex, smoking status, and diseased side. The volume of TAC between 2nd and 12th thoracic vertebrae was quantitatively measured with CT imaging, at baseline and at 1 year follow-up. The annual percent change in TAC was compared between the CRT and the control group. Moreover, the independent relationship between implementation of CRT and the progression of TAC was assessed by multivariate logistic regression analysis, adjusting for age, gender, conventional atherosclerotic risk factors and baseline aortic calcification volume.

Results

Patients in the CRT group received radiation (mean 47.3±4.0 Gy) and chemotherapy: 2 courses of cisplatin with docetaxel (34 cases) or vinorelbine (1 case). The prevalence of dyslipidemia, taking statins and diabetes drugs were significantly higher in the control groups (17% vs. 39%; p=0.041, 11% vs. 33%; p=0.029, 3% vs. 18%; p=0.044, respectively). Baseline C-reactive protein level was significantly higher in the CRT group (0.255 vs. 0.115; p=0.034). In univariate analysis, the annual percent change in TAC volume was significantly increased in the CRT group compared with the control group (37.6% vs. 23.3%; p=0.006). Multivariate logistic regression analysis demonstrated that CRT was an independent factor associated with the progression of TAC volume, even after adjustment for baseline calcification volume and coronary risk factors (OR, 3.90; 95% CI, 1.32–11.47; p=0.014).

Conclusion

CRT to patients with lung cancer exacerbates thoracic aortic calcification, which may result in future cardiovascular events.

P6453Activation of necroptotic pathway by downregulated caspase-8 expression is associated with progression of left ventricular remodeling in nonischemic dilated cardiomyopathy

Background

Necroptosis, a form of programmed necrosis, has been suggested to be involved in the pathogenesis of various pathological conditions including heart failure. Protein expression of caspase-8, an endogenous inhibitor of necroptosis, is reported to be downregulated in human failing hearts, but its clinical significance remains unclear.

Methods

Endomyocardial biopsy specimens were obtained from patients with nonischemic dilated cardiomyopathy (n=57, 56.2±14.5 years old, 70% male). The area stained with antibodies against caspase-8 and phospho-MLKL-Ser358 was calculated using an image analyzer, and fibrotic and cardiomyocyte areas were determined by Masson's Trichrome staining. Using a level of median caspase-8 expression (6.04% of the area of the myocardium with caspase-8 signal), patients were classified into a high caspase-8 expression group (H-cas8) and a low caspase-8 expression group (L-cas8).

Results

Caspase-8 signals were detected in cytoplasm and intercalated disks of cardiomyocytes. Patients in the L-cas8 group was younger (51.3±13.1 vs. 61.2±14.3 years old) and had larger left ventricular end-diastolic volume (LVEDV: 174±49 vs. 131±41 ml), larger left ventricular end-systolic volume (LVESV: 123±51 vs. 87±39 ml), and higher ratio of mitral peak velocity of early filling to late diastolic filling (E/A: 1.94±1.48 vs. 1.12±0.66) compared with the H-cas8 group. Caspase-8 expression level was positively correlated with age (r=0.34, p=0.01) and negatively correlated with LVEDV (r=−0.47, p<0.01), LVESV (r=−0.40, p<0.01), and E/A (r=−0.39, p<0.01) in simple linear regression analysis. The extent of myocardial fibrosis was not correlated with caspase-8 expression level. Multiple regression analysis indicated that LVEDV, LVESV, and E/A were independent explanatory factors of caspase-8 expression level after adjusting age and sex. Phospho-MLKL signals, an index of activation of necroptotic pathway, were frequently observed in cytoplasm, intercalated disks, and nuclei in the L-cas8 group but not in the H-cas8 group.

Conclusion

Lower caspase-8 expression in cardiomyocytes was associated with increased phosphorylation of MLKL and larger left ventricular volume, suggesting that downregulated caspase-8 may contribute to progression of myocardial remodeling via activation of MLKL in human dilated cardiomyopathy.

P6273Inhibitory phosphorylation of RIP1 at Ser320 induces nuclear translocation of TFEB, leading to suppression of necroptosis in cardiomyocytes

Background

Necroptosis, a form of programmed necrosis, has been shown to contribute to the pathogenesis of various diseases including ischemia/reperfusion injury and heart failure. We recently reported that necroptotic signals suppresses autophagy in cardiomyocytes and that rapamycin, an mTORC1 inhibitor, not only promotes autophagy but also protect the cells from necroptosis.

Purpose

We examined the mechanism by which rapamycin suppresses necroptosis of cardiomyocytes, focusing on regulation of RIP1 activity and autophagic flux.

Methods and results

In H9c2 cardiomyoblasts, necroptosis was induced by treatment with TNF and z-VAD-fmk (zVAD) for 24 h, and cell death was determined by LDH release (as % of total). The treatment with TNF/zVAD increased LDH release from 3.4±1.3% to 46.1±2.3%, and LDH release was suppressed by necrostatin-1 (5.9±0.9%), a RIP1 inhibitor, and by rapamycin (23.5±1.4%). The protective effect of rapamycin was mimicked by Ku-0063794, an mTORC1/2 inhibitor. TNF/zVAD induced RIP1-RIP3 complex formation, together with suppression of TNF-induced RIP1 cleavage, which was mitigated by rapamycin. In addition, rapamycin not only suppressed TNF/zVAD-induced phosphorylation of RIP1-Ser166, an index of RIP1 activation, but also increased phosphorylation of RIP1-Ser320, an inhibitory phosphorylation site. In cells transfected with RIP1-S320A, which lack Ser320 for inhibitory phosphorylation, rapamycin failed to suppress TNF/zVAD-induced RIP1-RIP3 binding and cell death. Immunoblot analyses showed that TNF/zVAD significantly increased level of LC3-II. The accumulation of LC3-II protein was not further increased by bafilomycin A1 (100 nM), an inhibitor of lysosomal protein degradation, indicating that accumulation of LC3-II by TNF/zVAD reflected suppression of autophagic flux. Inhibition of RIP1 by necrostatin-1 attenuated TNF/zVAD-induced accumulation of LC3 II. The restoration of autophagic flux in TNF/zVAD-treated cells by necrostatin-1 was confirmed by monitoring tandem RFP-GFP-LC3 transfected cells; necrostatin-1 increased a ratio of RFP-LC3-puncta (autolysosomes) to RFP-GFP-LC3-puncta (autophagosomes) in TNF/zVAD-treated cells. In addition, necrostatin-1 and rapamycin induced nuclear translocation of TFEB, a regulator of lysosome biogenesis, which was associated with upregulation of MCOLN1 mRNA, a downstream target of TFEB. Restoration of autophagic flux in TNF/zVAD-treated cells by necrostatin-1 was inhibited by siRNA-mediated knockdown of TFEB.

Conclusion

Activation of TFEB by inhibitiory phosphorylation of RIP1-Ser320 is a primary mechanism of cytoprotection afforded by mTORC1 inhibition against necroptosis.

Intrachoroidal Dye Leakage in Indocyanine Green Fundus Angiography after Experimental Commotio Retinae

Dye leakage in sodium fluorescein (FLUO) fundus angiography indicates damage to the blood-retinal barrier. However, dye leakage in indocyanine green (ICG) fundus angiography does not mean the same, because of the larger molecular size of the dye and impermeability of the choroidal vessels to it. The possibility of dye leakage in ICG angiography has not yet been revealed in an experimental study in which the blood-retinal barrier is undamaged. We report here that intrachoroidal dye leakage may occur in ICG angiography in an experimental model of the traumatic retinal opacity of the rabbit eye, even when the blood-retinal barrier is undamaged. This mechanism of dye leakage in ICG angiography is quite different from the leakage of FLUO angiography. Pathological choroidal vessels with increased permeability, such as choroidal neovascularization under the retinal pigment epithelium, can be observed using ICG angiography.

Change of Retinal Correspondence in Monocularly Reduced Intensity of Stimulus

We analyzed the retinal correspondence with a phase difference haploscope on reducing the stimulus intensity of a monocular image with a series of neutral density filters. Ninety-one exotropes were examined by this method. Five cases changed from normal to anomalous correspondence when the stimulation of the strabismic eye was reduced. Two cases showed anomalous correspondence without a filter, but normal correspondence with a reduced stimulus of the normal eye. All these seven cases showed normal correspondence with any other test. The results suggest that masked anomalous correspondence becomes manifest in some cases when the strabismic eye is stimulated more intensely than the normal eye. These cases display both normal and anomalous correspondence and this condition may be called dual correspondence.

Computer Assisted Image Analysis Using the Subtraction Method in Indocyanine Green Angiography

The choroidal vessels are three dimensionally distributed and very complex in their patterns. They often appear to be overlaid in indocyanine green (ICG) angiograms so it is harder to analyze ICG angiography than fluorescein angiography. When an earlier frame is subtracted from a later frame in a sequence of angiograms, the fluorescence which has increased during the time between the two frames can theoretically be demonstrated.

We applied computer-assisted image subtraction methods in selected clinical cases of directly acquired digital ICG angiography to demonstrate how this method works. We used software already installed in an IMAGEnet computer system (Topcon) for image subtraction. We applied the subtraction technique in 18 cases with various diseases. When two images with a time difference of several seconds were subtracted, filling of the choriocapillaris, the neovascularization or the pathological vessels could be observed. When the images had a time difference of several minutes, intrachoroidal dye leakage could be seen more clearly. This method is very helpful for analyzing pathological changes in ICG angiography in clinical cases, when two images are selected appropriately.

Digital Fluorescein Fundus Angiography with DFC-512 and Imagenet Systems

Image processing with direct acquisition digital fundus fluorescein angiography using the OIS DFC-512 and Topcon IMAGEnet were assessed. Fundus diseases included central and branch retinal vein occlusion, diabetic retinopathy, age-related macular degeneration, central serous choroidopathy and angioid streaks. Analogue images were taken with Kodak Tri-X 35 mm film as well. Although the resolution of the original image was less than that of 35 mm film, it was improved by image processing, particularly contrast enhancement. One type of contrast enhancement, available in both systems, exaggerated lack of light at the peripheral area of the original image. This drawback was not seen with another type of enhancement processing, available in IMAGEnet. However, the latter produced an artificial hypofluorescent area around an intensely hyperfluorescent lesion and also exaggerated hyper- and hypo-fluorescent patches of the background. Nevertheless, these processing methods were particularly useful in case of media opacity like cataract, even when the 35 mm film picture is not clear. Other processing techniques like pseudocolor and relief, etc. were used just for different ways of presentation. The two systems are basically equivalent, except for contrast enhancement. There was no problem for diagnosis in both systems, but the artificial effects must be borne in mind when interpreting the image.

Effect of sodium-glucose co-transporter-2 inhibitors on impaired ventricular repolarization in people with Type 2 diabetes

AIMS

To test the hypothesis that treatment with a sodium-glucose co-transporter-2 inhibitor would reverse ventricular repolarization heterogeneity, a predictor of cardiovascular mortality, in people with Type 2 diabetes.

METHODS

We retrospectively analysed changes in indices of ventricular repolarization before and after treatment with a sodium-glucose co-transporter-2 inhibitor in 46 people with Type 2 diabetes.

RESULTS

Sodium-glucose co-transporter-2 inhibitor treatment reduced HbA_1c concentration [62±13 mmol/mol (7.7±1.2%) vs 59±16 mmol/mol (7.5±1.4%)], body weight (77.8±13.9 vs 74.7±12.5 kg) and systolic blood pressure (133±18 vs 126±12 mmHg) in the study participants. Heart rate and QTc interval were not changed by sodium-glucose co-transporter-2 inhibitor treatment, but QTc dispersion was significantly reduced (median, 48.8 vs 44.2 ms). Sodium-glucose co-transporter-2 inhibitor treatment reversed QTc dispersion more in participants who had larger QTc dispersion before the treatment. Changes in systolic blood pressure (Spearman's ρ= 0.319; P=0.031), but not in HbA_1c concentration, were correlated with changes in QTc dispersion after sodium-glucose co-transporter-2 inhibitor treatment.

CONCLUSIONS

The findings suggest that sodium-glucose co-transporter-2 inhibitor treatment reverses ventricular repolarization heterogeneity in people with Type 2 diabetes, independently of its effect on glycaemic control. The favourable effect on ventricular repolarization heterogeneity could be the mechanism by which empaglifozin reduced cardiovascular events in a recent study.

Eicosapentaenoic acid ameliorates hyperglycemia in high-fat diet-sensitive diabetes mice in conjunction with restoration of hypoadiponectinemia

Background/Objective:

Eicosapentaenoic acid (EPA) exerts pleiotropic effects on metabolic disorders such as atherosclerosis and dyslipidemia, but its effectiveness in the treatment of type 2 diabetes mellitus remains controversial.

Methods:

We examined the antidiabetic effect of EPA in insulin receptor mutant (Insr^P1195L/+) mice that exhibit high-fat diet (HFD)-dependent hyperglycemia.

Results:

EPA supplementation was found to alleviate hyperglycemia of Insr^P1195L/+ mice fed HFD (Insr^P1195L/+/HFD mice), which was accompanied by amelioration of increased gluconeogenesis and impaired insulin signaling, as assessed by glucose-6-phosphatase (G6pc) expression on refeeding and insulin-induced phosphorylation of Akt in the liver, respectively. We found that serum levels of adiponectin, the antidiabetic adipokine, were decreased by HFD along with the body weight gain in Insr^P1195L/+ mice but not in wild-type mice, suggesting that Insr^P1195L/+ mice are prone to hypoadiponectinemia in response to obesity. Interestingly, the blood glucose levels of Insr^P1195L/+ mice were in reverse proportion to their serum adiponectin levels and EPA supplementation ameliorated their hyperglycemia in conjunction with the restoration of hypoadiponectinemia.

Conclusions:

EPA exerts an antidiabetic effect in Insr^P1195L/+/HFD mice, an HFD-sensitive, insulin-resistant animal model, possibly through its action against hypoadiponectinemia.

Circulating bone Gla protein in end-stage renal disease determined by newly developed two-site immunoradiometric assay

As a marker for bone formation, bone Gla protein (BGP) levels in the circulation have been measured in clinical research and management for metabolic bone diseases. We evaluated the clinical availability of a newly developed two-site immunoradiometric assay (IRMA) for human BGP and determined the serum BGP concentrations using this methodology in patients with abnormal calcium metabolism including those with end-stage renal disease undergoing maintenance dialysis. A cross-reactivity test revealed that this assay system specifically recognizes intact molecules (1-49) of BGP and excludes fragments of the molecules (1-19, 12-33, 23-33). Serum BGP levels in dialysis patients were positively correlated with those by conventional radioimmunoassay (RIA) (r = 0.918, p less than 0.00001, n = 37) as well as normal individuals (r = 0.935, p less than 0.0001, n = 16). However, the levels of BGP determined by IRMA were estimated to be significantly lower than those by RIA (23.6 +/- 9.8 vs. 29.6 +/- 9.1 ng/ml, p less than 0.00001). These results suggest that this IRMA system, with a rapid and easy procedure, excludes fragment forms of BGP in the circulation, which are found in uremic sera and probably attributed to increased bone resorption. Further studies are needed to ensure that serum intact BGP levels mainly reflect BGP production in osteoblasts, particularly in end-stage renal disease.

Decreased bone mineral density in diabetic patients on hemodialysis

Renal osteodystrophy in hemodialyzed patients with DM-HD shows different features from that in non-DM,HD. Two studies were done. One was a comparison of BMD in 30 non-DM,HD patients and 30 DM-HD patients. The second was a comparison of possible factors affecting calcium metabolism in the higher and lower BMD groups (n = 20/21) in the DM-HD patients. BMD was measured by dual-energy X-ray absorptiometry (DEXA; Hologic QDR 1,000/W) in the third lumbar vertebra (L3), head, pelvis, and whole body. The BMDs of the DM-HD group were lower in these areas and whole body than that in the non-DM,HD group. A significant difference was found in the head BMD (p less than 0.05). In the second study, factors which may contribute to the differences in BMD were compared in the DM-HD patients divided into higher and lower BMD of the head. The group with higher head BMD had a value 110% of the mean value or more. Clinical and biochemical test results (age, the time since the first dialysis, body weight, the degree of obesity, height, serum calcium, serum phosphate, serum aluminum, serum c-PTH level and the dose of 1 alpha-OH-D3) were compared. The degree of obesity of the patients with higher BMD was significantly larger than that with lower BMD (p less than 0.005).

Parathyroid hormone secretion in diabetes mellitus

To investigate the parathyroid function in diabetes mellitus, we performed an oral phosphate load in 6 diabetic patients and 6 nondiabetic subjects without renal failure (serum creatinine less than 1.5 mg/dl). Each subject received a total of 2.0 g of phosphate daily per os on 5 consecutive days. Blood and urine samples were obtained daily before and 2 h after the administration of phosphate in the morning. All subjects responded with a similar increase in the serum phosphorus concentration and fall in the ionized calcium concentration. Intact parathyroid hormone levels rose by 2.6-fold in the control subjects but by less than 1.5-fold in the diabetic subjects. It was concluded that hyporesponsiveness of the parathyroid hormone to phosphate administration was found in the diabetic patients without renal failure.

Three-year denosumab treatment in postmenopausal Japanese women and men with osteoporosis: results from a 1-year open-label extension of the Denosumab Fracture Intervention Randomized Placebo Controlled Trial (DIRECT)

SUMMARY

A 12-month extension phase of DIRECT in Japanese subjects with osteoporosis showed that total 3 years of denosumab treatment in Japanese postmenopausal women and men with osteoporosis was associated with low fracture rates, persistent bone turnover marker (BTM) reductions, continuous bone mineral density (BMD) increases, and a favorable overall benefit/risk profile.

INTRODUCTION

The DIRECT trial demonstrated that 2 years of treatment with denosumab 60 mg subcutaneously every 6 months significantly reduced the incidence of vertebral fracture compared to placebo in Japanese postmenopausal women and men with osteoporosis. The purpose of this study is to evaluate the efficacy and safety of denosumab treatment for up to 3 years.

METHODS

This study includes a 2-year randomized, double-blind, placebo-controlled phase and a 1-year open-label extension phase in which all subjects received denosumab. The data correspond to 3 years of denosumab treatment in subjects who received denosumab (long-term group) and 1 year of denosumab treatment in subjects who received placebo (cross-over group) in the double-blind phase.

RESULTS

Eight hundred and ten subjects who completed the double-blind phase enrolled into the extension phase, and 775 subjects completed the study. All subjects received denosumab with daily supplements of calcium and vitamin D. The cumulative 36-month incidences of new or worsening vertebral fractures and new vertebral fractures were 3.8 and 2.5 %, respectively, in the long-term group. In this group, the BMD continued to increase, and the reduction in BTMs was maintained. In the cross-over group, comparable BMD increases and BTMs reductions to those of in their first year of the long-term group were confirmed. Adverse events did not show a notable increase with long-term denosumab administration. One event of osteonecrosis of the jaw occurred in the cross-over group.

CONCLUSIONS

Three-year denosumab treatment in Japanese subjects with osteoporosis showed a favorable benefit/risk profile.

IQ is an independent predictor of glycated haemoglobin level in young and middle-aged adults with intellectual disability

AIMS

Here we examined whether intellectual disability is independently associated with hyperglycaemia.

METHODS

We recruited 233 consecutive young and middle-aged adults with intellectual disability. After exclusion of subjects on medication for metabolic diseases or with severe intellectual disability (IQ < 35), 121 subjects were divided by IQ into a group with moderate intellectual disability (35 ≤ IQ ≤ 50), a mild intellectual disability group (51 ≤ IQ ≤ 70) and a borderline group (IQ > 70).

RESULTS

HbA1c level was higher in subjects with moderate intellectual disability (42 ± 9 mmol/mol; 6.0 ± 0.8%) than those in the borderline group (36 ± 4 mmol/mol; 5.5 ± 0.3%) and mild intellectual disability group (37 ± 5 mmol/mol; 5.5 ± 0.5%) groups. HbA1c level was correlated with age, BMI, blood pressure, serum triglycerides and IQ in simple linear regression analysis. Multiple regression analysis indicated that IQ, age, BMI and diastolic blood pressure were independent explanatory factors of HbA1c level.

CONCLUSIONS

An unfavourable effect of intellectual disability on lifestyle and untoward effect of hyperglycaemia on cognitive function may underlie the association of low IQ with hyperglycaemia.

Missense variants of the alanine: glyoxylate aminotransferase 2 gene correlated with carotid atherosclerosis in the Japanese population

Alanine:glyoxylate aminotransferase 2 (AGXT2; EC 2.6.1.44) degrades asymmetric dimethylarginine (ADMA), a competitive inhibitor of nitric oxide (NO) synthase. Increased ADMA, reduced NO, and hypertension are shown in Agxt2 knockout mice. There are four single nucleotide polymorphisms (rs37370, rs37369, rs180749, and rs16899974) with which AGXT2 activity changes in humans and may be related to vulnerability of vascular sclerosis. To examine the relationship between them, we studied the functional haplotypes of the AGXT2 gene and decided their relationship with arteriosclerotic changes via carotid intima-media thickness (carotid IMT) in Japanese subjects. Genotyping of those polymorphisms and the carotid IMT in 1,426 Japanese subjects were then evaluated. Subjects with C-A-A-A haplotype (rs37370, rs37369, rs180749, rs16899974) showed low AGXT2 activity (P<0.0001; Pearson’s correlation coefficients: 0.497). The C-A-A-A haplotype was significantly associated with mean carotid IMT (P=0.049) and max carotid IMT (P=0.004). Subjects with two C-A-A-A haplotypes exhibited thicker mean carotid IMT (P=0.022) and maximum carotid IMT (P=0.001). In multiple regression analysis, subjects with two C-A-A-A haplotypes were independently and positively associated with mean carotid IMT (P=0.02) and maximum IMT (P=0.005) after correction. There was a significant correlation between the functional variants in the AGXT2 gene and carotid IMT in Japanese. The AGXT2 genotype may be an important factor underlying atherosclerosis.