Quantification of right ventricular amyloid burden with 18F-florbetapir positron emission tomography/computed tomography and its association with right ventricular dysfunction and outcomes in light-chain amyloidosis

AIMS

In systemic light-chain (AL) amyloidosis, quantification of right ventricular (RV) amyloid burden has been limited and the pathogenesis of RV dysfunction is poorly understood. Using 18F-florbetapir positron emission tomography/computed tomography (PET/CT), we aimed to quantify RV amyloid; correlate RV amyloid with RV structure and function; determine the independent contributions of RV, left ventricular (LV), and lung amyloid to RV function; and associate RV amyloid with major adverse cardiac events (MACE: death, heart failure hospitalization, cardiac transplantation).

METHODS AND RESULTS

We prospectively enrolled 106 participants with AL amyloidosis (median age 62 years, 55% males) who underwent 18F-florbetapir PET/CT, magnetic resonance imaging, and echocardiography. 18F-florbetapir PET/CT identified RV amyloid in 63% of those with and 40% of those without cardiac involvement by conventional criteria. RV amyloid burden correlated with RV ejection fraction (EF), RV free wall longitudinal strain (FWLS), RV wall thickness, RV mass index, N-terminal pro-brain natriuretic peptide, troponin T, LV amyloid, and lung amyloid (each P < 0.001). In multivariable analysis, RV amyloid burden, but not LV or lung amyloid burden, predicted RV dysfunction (EF P = 0.014; FWLS P < 0.001). During a median follow-up of 28 months, RV amyloid burden predicted MACE (P < 0.001).

CONCLUSION

This study shows for the first time that 18F-florbetapir PET/CT identifies early RV amyloid in systemic AL amyloidosis prior to alterations in RV structure and function. Increasing RV amyloid on 18F-florbetapir PET/CT is associated with worse RV structure and function, predicts RV dysfunction, and predicts MACE. These results imply a central role for RV amyloid in the pathogenesis of RV dysfunction.

Generation of two induced pluripotent stem cell lines from hereditary amyloidosis patients with polyneuropathy carrying heterozygous transthyretin (TTR) mutation

Hereditary transthyretin amyloidosis with polyneuropathy (ATTR-PN) results from specific TTR gene mutations. In this study, we generated two induced pluripotent stem cell (iPSC) lines derived from ATTR-PN patients with heterozygous TTR gene mutations (Ala97Ser and Phe64Leu). These iPSC lines exhibited normal morphology, karyotype, high pluripotency marker expression, and differentiation into cells representing all germ layers. The generation of these iPSC lines serve as a valuable tool for investigating the mechanisms of ATTR-PN across various cell types and facilitating patient-specific in vitro amyloidosis modeling.

Signal intensity coefficient as a detector of aortic stenosis-induced myocardial fibrosis and its correlation to the long term outcome

OBJECTIVE

Despite advanced aortic valve replacement techniques, aortic stenosis (AS)-induced irreversible myocardial fibrosis contributes to poorer outcomes. Therefore, in addition to early diagnosis of AS, detecting myocardial fibrosis is crucial for physicians to determine the timing of surgery. The Signal Intensity Coefficient (SIC) was used to detect subtle myocardial deformation. Hence, we aimed to investigate whether SIC correlated with myocardial dysfunction and fibrosis from both clinical and preclinical perspectives.

METHODS

We collected medical records and echocardiography images, including the SIC of patients who underwent surgical aortic valve replacement (AVR) for AS from 2010 to 2015. The endpoint of the study was mortality. Median follow-up period was 80 months.

RESULTS

Among 109 patients, 15 died due to cardiovascular causes. Although SIC decreased in all patients post-AVR, patients with an SIC ≥0.34 before surgeries presented with a higher probability of cardiovascular death. In contrast, changes in the left ventricular (LV) ejection fraction, LV mass index, and LV volume failed to predict outcomes. Similarly, SIC was obtained in mice undergoing aortic banding and debanding surgery for comparison with the degree of myocardial fibrosis. SIC was continuously elevated after aortic banding and declined gradually after debanding surgery in mice. Debanding surgery indicated the regression of aortic banding-induced myocardial fibrosis.

CONCLUSION

Pre-AVR SIC was associated with the risk of cardiovascular death and reflected the degree of myocardial fibrosis. Further investigations are required to study the clinical application of SIC in patients with AS.

Myocardial Characterization for Early Diagnosis, Treatment Response Monitoring, and Risk Assessment in Systemic Light-Chain Amyloidosis

Aims

In systemic light-chain (AL) amyloidosis, cardiac involvement portends poor prognosis. Using myocardial characteristics on magnetic resonance imaging (MRI), this study aimed to detect early myocardial alterations, to analyze temporal changes with plasma cell therapy, and to predict risk of major adverse cardiac events (MACE) in AL amyloidosis.

Methods and Results

Participants with recently diagnosed AL amyloidosis were prospectively enrolled. Presence of AL cardiomyopathy (AL-CMP vs. AL-non-CMP) was determined by abnormal cardiac biomarkers. MRI was performed at baseline and 6 months, with 12-month imaging in AL-CMP cohort. MACE was defined as all-cause death, heart failure hospitalization, or cardiac transplantation. Mayo AL stage was based on troponin T, NT-proBNP, and difference in free light chains. The study cohort included 80 participants (median age 62 years, 58% males). Median left ventricular extracellular volume (ECV) was significantly higher in AL-CMP (53% vs. 30%, p<0.001). ECV was abnormal (>32%) in all AL-CMP and in 47% of AL-non-CMP. ECV tended to increase at 6 months and decreased significantly from 6 to 12 months in AL-CMP (median -3%, p=0.011). ECV was strongly associated with MACE (p<0.001), and improved MACE prediction when added to Mayo AL stage (p=0.002). ECV≤32% identified a cohort without MACE, while ECV>48% identified a cohort with 74% MACE.

Conclusions

In AL amyloidosis, ECV detects subclinical cardiomyopathy. ECV tends to increase from baseline to 6 months and decreases significantly from 6 and 12 months of plasma cell therapy in AL-CMP. ECV provides excellent risk stratification and offers additional prognostic performance over Mayo AL stage.

Prognostic Value of Left Ventricular 18 F-Florbetapir Uptake in Systemic Light-Chain Amyloidosis

Background

Myocardial immunoglobulin light-chain (AL) amyloid deposits trigger heart failure, cardiomyocyte stretch and myocardial injury, leading to adverse cardiac outcomes. Positron emission tomography/computed tomography (PET/CT) with 18 F-florbetapir, a novel amyloid-targeting radiotracer, can quantify left ventricular (LV) amyloid burden, but its prognostic value is not known. Therefore, we aimed to evaluate the prognostic value of LV amyloid burden quantified by 18 F-florbetapir PET/CT and to identify mechanistic pathways mediating its association with outcomes.

Methods

Eighty-one participants with newly-diagnosed systemic AL amyloidosis were prospectively enrolled and underwent 18 F-florbetapir PET/CT. LV amyloid burden was quantified using 18 F-florbetapir LV percent injected dose (%ID). Mayo AL stage was determined using troponin T, N-terminal pro-B-type natriuretic peptide (NT-proBNP), and difference between involved and uninvolved free light chain levels. Major adverse cardiac events (MACE) were defined as all-cause death, heart failure hospitalization, or cardiac transplantation within 12 months.

Results

Among participants (median age 61 years, 57% males), 36% experienced MACE. Incidence of MACE increased across tertiles of LV amyloid burden from 7% to 63% (p<0.001). LV amyloid burden was significantly associated with MACE in univariable analysis (hazard ratio 1.45, 95% confidence interval 1.15-1.82, p=0.002). However, this association became non-significant in multivariable analyses adjusted for Mayo AL stage. Mediation analysis showed that the association between 18 F-florbetapir LV %ID and MACE was primarily mediated by NT-proBNP (p<0.001), a marker of cardiomyocyte stretch and component of Mayo AL stage.

Conclusion

In this first study to link cardiac 18 F-florbetapir uptake to subsequent outcomes, LV amyloid burden estimated by LV %ID predicted MACE in AL amyloidosis. But this effect was not independent of Mayo AL stage. LV amyloid burden was associated with MACE primarily via NT-pro-BNP, a marker of cardiomyocyte stretch and component of Mayo AL stage. These findings provide novel insights into the mechanism through which myocardial AL amyloid leads to MACE.

Clinical Perspective

In systemic light-chain (AL) amyloidosis, cardiac involvement is the key determinant of adverse outcomes. Usually, prognosis is based on the Mayo AL stage, determined by troponin T, N-terminal pro-B-type natriuretic peptide (NT-proBNP), and the difference between involved and uninvolved immunoglobulin free light chain levels (dFLC). Cardiac amyloid burden is not considered in this staging. In the present study, we used the amyloid-specific radiotracer 18 F-florbetapir to quantify left ventricular (LV) amyloid burden in 81 participants with newly-diagnosed AL amyloidosis and evaluated its prognostic value on major adverse outcomes (MACE: all-cause death, heart failure hospitalization, or cardiac transplantation within 12 months). We found that higher LV amyloid burden by 18 F-florbetapir positron emission tomography/computed tomography (PET/CT) was strongly associated with MACE. However, this association became non-significant after adjustment for the Mayo AL stage. Mediation analysis offered novel pathophysiological insights, implying that LV amyloid burden leads to MACE predominantly through cardiomyocyte stretch and light chain toxicity (by NT-proBNP), rather than through myocardial injury (by troponin T), also considering the severity of plasma cell dyscrasia (by dFLC). This mediation by NT-proBNP may explain why the association with outcomes was non-significant with adjustment for Mayo AL stage. Together, these results establish quantitative 18 F-florbetapir PET/CT as a valid method to predict adverse outcomes in AL amyloidosis. These results support the use of 18 F-florbetapir PET/CT to measure the effects of novel fibril-depleting therapies, in addition to plasma cell therapy, to improve outcomes in systemic AL amyloidosis.

[A comparison of current guidelines for the management of intrahepatic cholangiocarcinoma worldwide]

Intrahepatic cholangiocarcinoma (ICC) is the second most common human liver malignancy and its incidence rate has been gradually increasing worldwide over the past decades. Surgical resection (R0 resection) is the preferred potentially curative treatment for ICC patients. However, due to its conceal clinical features and high invasiveness, most patients have lost the opportunity for surgical resection at the time of diagnosis. In recent years, with the rapid development of targeted therapy and immunotherapy, which is represented by immune checkpoint inhibitors, clinicians are expected to provide more effective treatment options for patients with mid-stage or advanced ICC. At present, there are still controversial opinions on different guidelines regarding preoperative biliary drainage, the extent of hepatectomy, the definition of R0 resection, the width of the resection margin, lymph node dissection, postoperative recurrence, adjuvant therapy, etc. In this review, 12 guidelines or expert consensus published worldwide from 2012 to 2022 (including 4 Chinese guidelines, 4 European guidelines, 2 American guidelines and 2 Japanese guidelines) were retrieved. Focusing on sorting and comparing the current views on clinical management of ICC in different guidelines, this review aims to provide reference information for ICC clinical management and decision-making.

Effect of Multicomponent Intervention on Functional Decline in Chinese Older Adults: A Multicenter Randomized Clinical Trial

OBJECTIVES

To confirm whether multicomponent exercise following vivifrail recommendations was an effective method for improving physical ability, cognitive function, gait, balance, and muscle strength in Chinese older adults.

METHODS

This was a multicenter and randomized clinical trial conducted in Jiangsu, China, from April 2021 to April 2022. Intervention lasted for 12 weeks and 104 older adults with functional declines were enrolled. All participants were randomly assigned to a control (usual care plus health education) or exercise group (usual care plus health education plus exercise). Primary outcomes were the change score of Short Physical Performance Battery (SPPB) and activities of daily living (ADL). The secondary outcomes included instrumental activities of daily living, Tinetti scores, Frailty score, short-form Mini Nutritional Assessment, Mini-Mental State Examination, Geriatric Depression Scale-15, the 12-item Short Form Survey, 4-meter gait speed test, 6-min walking distance, grip strength, and body composition analysis.

RESULTS

Among the participants, the average age was 85 (82, 88) years. After 12 weeks of follow-up, the exercise group showed a significant improvement in SPPB, with a change of 2 points (95% confidence interval [0, 3.5], P<0.001) compared to control. In contrast, SPPB remained stable in the control group. Compared to the control group, ADL improved in the exercise group, as did instrumental activities of daily living, Tinetti, Frailty, Short Form Survey, 4-meter gait speed test, and 6-min walking distance. Although there was no significant difference between groups in body composition analysis after post-intervention, the exercise group still improved in soft lean mass (P=0.002), fat-free mass (P=0.002), skeletal muscle mass index (P<0.001), fat-free mass index (P=0.004), appendicular skeletal muscle mass (P<0.001), and leg muscle mass (P<0.001), while the control group had no significant increase. No difference was observed in adverse events during trial period.

CONCLUSIONS

The multicomponent exercise intervention following vivifrail recommendations is an effective method for older adults with functional decline and can reverse the functional decline and improve gait, balance, and muscle strength. Additionally, the 12-week multicomponent exercise method provides guidance for Chinese medical professionals working in the field of geriatrics and is a promising method to improve physical function in the general population.

Intervention effect of Potentilla discolor-Euonymus alatus on intestinal flora of type 2 diabetes mellitus rats

OBJECTIVE

With this study, we aimed at exploring the regulation mechanism of Potentilla discolor-Euonymus alatus on intestinal flora of T2DM (Type 2 Diabetes Mellitus) rats induced by high-fat diet combined with streptozotocin.

MATERIALS AND METHODS

T2DM rats were induced by high-fat diet combined with streptozotocin. There were normal control group, model group, metformin group, high-dose Chinese medicine group and low-dose Chinese medicine group. Each group included 10 rats. Normal control group: normal feeding, no modeling, ordinary feed, and gavage of 0.9% normal saline. Model group: T2DM rats, high-fat diet, and gavage of 0.9% normal saline. Metformin group: T2DM rats, high-fat diet and fed with metformin solution. High-dose Chinese medicine group: T2DM rats, high-fat diet, and gavage of concentrated Chinese medicine at a dose of 6 times the clinical dose. Low-dose Chinese medicine group: T2DM rats, high-fat diet, and gavage of concentrated Chinese medicine at a dose twice the clinical dose. The general situation of T2DM rats was observed, and the changes of intestinal flora were observed with 16SrDNA sequencing.

RESULTS

The T2DM rats induced by high-fat diet combined with streptozotocin were molded. After intervention, at the class level, the ratio of γ-proteobacteria was 22.30% in the model group, 11.97% in the metformin group, 3.24% in the high-dose Chinese herbs group and 1.72% in the low-dose Chinese herbs group; the ratio of Erysipelothrix insidiosa was 4.73% in the model group, 4.68% in the metformin group, 3.93% in the high-dose Chinese herbsgroup and 2.92% in the low dose group; the ratio of Lactinobacillus was 2.30% in the model group, 0.01% in the metformin group, 0.00% in the high-dose Chinese herbs group, and 0.00% low-dose Chinese herbs group; at the portal level, the Firmicutes/Bacteroides was 0.88 in the normal control group, 3.40 in the model group, 1.71 in the metformin group, 2.74 in high-dose Chinese medicine group, and 1.34 in low-dose Chinese medicine group; at the genus level, the relative abundance of Lactobacillus in the model group was 3.28%, that of Akkermansia was 1.99%, that of Shigella coli was 22.08%, and that of Vibrio phaseus was 7.67%. All of them were improved after the intervention of metformin and traditional Chinese medicine.

CONCLUSIONS

Potentilla discolor-Euonymus Alatus could improve the composition and structure of intestinal flora in T2DM rats and regulate the diversity of intestinal flora. The ratio of Firmicutes/Bacteroidetes was adjusted, mainly to increase the number of Bacteroides; the flora related to intestinal barrier was adjusted, mainly to increase the number of Lactobacillus and Akkermansia bacteria.

Antagonistic Cd and Zn isotope behavior in the extracted soil fractions from industrial areas

The remobilization of metals accumulated in contaminated soils poses a threat to humans and ecosystems in general. Tracing metal fractionation provides valuable information for understanding the remobilization processes in smelting areas. Based on the difference between the isotopic system of Cd and Zn, this work aimed to couple isotope data and their leachability to identify possible remobilization processes in several soil types and land uses. For soil samples, the δ^66/64Zn values ranged from 0.12 ± 0.05‰ to 0.28 ± 0.05‰ in Avilés (Spain) and from - 0.09 ± 0.05‰ to - 0.21 ± 0.05‰ in Příbram (Czech Republic), and the δ^114/110Cd ranged from - 0.13 ± 0.05‰ to 0.01 ± 0.04‰ in Avilés and from - 0.86 ± 0.27‰ to - 0.24 ± 0.05‰ in Příbram. The metal fractions extracted using chemical extractions were always enriched in heavier Cd isotopes whilst Zn isotope systematics exhibited light or heavy enrichment according to the soil type and land uses. Coupling Zn and Cd systematics provided a tool for deciphering the mechanisms behind the remobilization processes: leaching of the anthropogenic materials and/or metal redistribution within the soil components prior to remobilization.

Cardiomyocyte stretch mediates the relation between left ventricular amyloid burden and adverse outcomes in light chain amyloidosis: a 18F-florbetapir positron emission tomography study

Background

Patients with light chain (AL) amyloidosis and cardiac involvement have poor prognosis. Mayo stage accounts for severity of plasma cell dyscrasia and cardiac biomarker release, and provides powerful risk stratification. Myocardial amyloid burden can be quantified by 18F-florbetapir positron emission tomography (PET), but its prognostic value is not known.

Purpose

To test our hypothesis that (1) myocardial amyloid burden predicts adverse outcomes and (2) the relationship between amyloid burden and adverse outcomes is mediated by cardiomyocyte stretch and injury. Amyloid burden was estimated by left ventricular 18F-florbetapir retention index (RI) and cardiomyocyte stretch and injury by NT proBNP and troponin T respectively.

Methods

We performed 18F-florbetapir PET (median dose 9.05 mCi) in prospectively enrolled subjects with newly diagnosed AL amyloidosis with abnormal cardiac biomarkers or with normal cardiac biomarkers and normal left ventricular wall thickness (NCT02641145). Left ventricular RI was calculated as the activity concentration between 10 and 30 min. after injection divided by the integral of the left atrial blood time-activity curve from 0 to 20 min. RI was categorized as normal (&lt;0.06/min, based on controls), increased (0.06–0.12/min), or high risk (&gt;0.12/min, based on log-rank statistic maximization). Mayo stages I–IV were based on elevated serum cardiac biomarkers: NT-proBNP ≥1800 pg/ml, troponin T ≥0.025 ng/ml, and difference in free light chains ≥180 mg/l. Adverse outcomes of all-cause death or heart failure hospitalization were evaluated. Survival analysis was performed using Kaplan-Meier and Cox regression including Mayo stage and RI. Mediation analysis was used to elucidate the role of cardiomyocyte stretch (as NT-proBNP) and injury (as troponin T) in the association between amyloid burden estimated by RI and adverse outcomes.

Results

We studied 80 subjects with median age 62 years (IQR 57–67), 46 men (57%), 60 with abnormal cardiac biomarkers (75%), and median RI of 0.10/min (IQR 0.06–0.16). At follow-up (median 15 months), adverse outcomes occurred in 34 subjects (42%), with 17 deaths (21%) and 23 heart failure hospitalizations (29%). The incidence of adverse outcomes increased across Mayo stages from 9% to 44% (log-rank p&lt;0.001), and across RI levels from 29% to 57% (log-rank p=0.037, Figure 1). In multivariable Cox regression, only Mayo stage independently predicted adverse outcomes (HR 2.0 [95% CI 1.4–3.0], p&lt;0.001). Multivariable mediation analysis showed that 83% of the association between RI and adverse outcomes was mediated by NT-proBNP (p&lt;0.001, Figure 2), without contribution from troponin T.

Conclusion

Myocardial amyloid burden estimated by F-18 florbetapir RI predicts adverse outcomes in AL amyloidosis, but not independently of Mayo stage. Cardiomyocyte stretch mediates the relationship between myocardial amyloid burden and adverse outcomes in AL amyloidosis.

Funding Acknowledgement

Type of funding sources: Private company.

L-2-Hydroxyglutarate Protects Against Cardiac Injury via Metabolic Remodeling

BACKGROUND

L-2-hydroxyglutarate (L2HG) couples mitochondrial and cytoplasmic energy metabolism to support cellular redox homeostasis. Under oxygen-limiting conditions, mammalian cells generate L2HG to counteract the adverse effects of reductive stress induced by hypoxia. Very little is known, however, about whether and how L2HG provides tissue protection from redox stress during low-flow ischemia (LFI) and ischemia-reperfusion injury. We examined the cardioprotective effects of L2HG accumulation against LFI and ischemia-reperfusion injury and its underlying mechanism using genetic mouse models.

METHODS AND RESULTS

L2HG accumulation was induced by homozygous (L2HGDH [L-2-hydroxyglutarate dehydrogenase]-/-) or heterozygous (L2HGDH+/-) deletion of the L2HGDH gene in mice. Hearts isolated from these mice and their wild-type littermates (L2HGDH+/+) were subjected to baseline perfusion and 90-minute LFI or 30-minute no-flow ischemia followed by 60- or 120-minute reperfusion. Using [13C]- and [31P]-NMR (nuclear magnetic resonance) spectroscopy, high-performance liquid chromatography, reverse transcription quantitative reverse transcription polymerase chain reaction, ELISA, triphenyltetrazolium staining, colorimetric/fluorometric spectroscopy, and echocardiography, we found that L2HGDH deletion induces L2HG accumulation at baseline and under stress conditions with significant functional consequences. In response to LFI or ischemia-reperfusion, L2HG accumulation shifts glucose flux from glycolysis towards the pentose phosphate pathway. These key metabolic changes were accompanied by enhanced cellular reducing potential, increased elimination of reactive oxygen species, attenuated oxidative injury and myocardial infarction, preserved cellular energy state, and improved cardiac function in both L2HGDH-/- and L2HGDH+/- hearts compared with L2HGDH+/+ hearts under ischemic stress conditions.

CONCLUSION

L2HGDH deletion-induced L2HG accumulation protects against myocardial injury during LFI and ischemia-reperfusion through a metabolic shift of glucose flux from glycolysis towards the pentose phosphate pathway. L2HG offers a novel mechanism for eliminating reactive oxygen species from myocardial tissue, mitigating redox stress, reducing myocardial infarct size, and preserving high-energy phosphates and cardiac function. Targeting L2HG levels through L2HGDH activity may serve as a new therapeutic strategy for cardiovascular diseases related to oxidative injury.

Reengineering Ponatinib to Minimize Cardiovascular Toxicity

Small molecule tyrosine kinase inhibitors (TKI) have revolutionized cancer treatment and greatly improved patient survival. However, life-threatening cardiotoxicity of many TKIs has become a major concern. Ponatinib (ICLUSIG) was developed as an inhibitor of the BCR-ABL oncogene and is among the most cardiotoxic of TKIs. Consequently, use of ponatinib is restricted to the treatment of tumors carrying T315I-mutated BCR-ABL, which occurs in chronic myeloid leukemia (CML) and confers resistance to first- and second-generation inhibitors such as imatinib and nilotinib. Through parallel screening of cardiovascular toxicity and antitumor efficacy assays, we engineered safer analogs of ponatinib that retained potency against T315I BCR-ABL kinase activity and suppressed T315I mutant CML tumor growth. The new compounds were substantially less toxic in human cardiac vasculogenesis and cardiomyocyte contractility assays in vitro. The compounds showed a larger therapeutic window in vivo, leading to regression of human T315I mutant CML xenografts without cardiotoxicity. Comparison of the kinase inhibition profiles of ponatinib and the new compounds suggested that ponatinib cardiotoxicity is mediated by a few kinases, some of which were previously unassociated with cardiovascular disease. Overall, the study develops an approach using complex phenotypic assays to reduce the high risk of cardiovascular toxicity that is prevalent among small molecule oncology therapeutics.

SIGNIFICANCE

Newly developed ponatinib analogs retain antitumor efficacy but elicit significantly decreased cardiotoxicity, representing a therapeutic opportunity for safer CML treatment.

Large and Small Animal Models of Heart Failure With Reduced Ejection Fraction

Heart failure (HF) describes a heterogenous complex spectrum of pathological conditions that results in structural and functional remodeling leading to subsequent impairment of cardiac function, including either systolic dysfunction, diastolic dysfunction, or both. Several factors chronically lead to HF, including cardiac volume and pressure overload that may result from hypertension, valvular lesions, acute, or chronic ischemic injuries. Major forms of HF include hypertrophic, dilated, and restrictive cardiomyopathy. The severity of cardiomyopathy can be impacted by other comorbidities such as diabetes or obesity and external stress factors. Age is another major contributor, and the number of patients with HF is rising worldwide in part due to an increase in the aged population. HF can occur with reduced ejection fraction (HF with reduced ejection fraction), that is, the overall cardiac function is compromised, and typically the left ventricular ejection fraction is lower than 40%. In some cases of HF, the ejection fraction is preserved (HF with preserved ejection fraction). Animal models play a critical role in facilitating the understanding of molecular mechanisms of how hearts fail. This review aims to summarize and describe the strengths, limitations, and outcomes of both small and large animal models of HF with reduced ejection fraction that are currently used in basic and translational research. The driving defect is a failure of the heart to adequately supply the tissues with blood due to impaired filling or pumping. An accurate model of HF with reduced ejection fraction would encompass the symptoms (fatigue, dyspnea, exercise intolerance, and edema) along with the pathology (collagen fibrosis, ventricular hypertrophy) and ultimately exhibit a decrease in cardiac output. Although countless experimental studies have been published, no model completely recapitulates the full human disease. Therefore, it is critical to evaluate the strength and weakness of each animal model to allow better selection of what animal models to use to address the scientific question proposed.

LB0002 BARICITINIB IN JUVENILE IDIOPATHIC ARTHRITIS: A PHASE 3, DOUBLE-BLIND, PLACEBO-CONTROLLED, WITHDRAWAL, EFFICACY AND SAFETY STUDY

Background

Baricitinib is a JAK1/2 selective inhibitor approved for the treatment of rheumatoid arthritis. Juvenile idiopathic arthritis (JIA) is a group of diseases characterized by immune mediated chronic arthritis which often requires treatment with conventional synthetic or biologic disease-modifying antirheumatic drugs (cs or b-DMARDs).

Objectives

To investigate baricitinib efficacy and safety in pediatric patients with JIA and an inadequate response to cs or b-DMARDs.

Methods

This Phase 3 multicenter, double-blind, withdrawal, efficacy, and safety study, enrolled patients (pts) age 2 to <18 years with extended oligo- or poly-articular JIA, ERA, or JPsA, per ILAR criteria, and an inadequate response to ≥1 cs and/or b-DMARDs (NCT03773978). There were 3 periods: a 2-week (wk) pharmacokinetic/safety assessment (PKS), a 12-wk open-label lead-in (OLLI), and an up-to 32-wk double-blind withdrawal (DBW). Dosage and safety were confirmed in the PKS and then pts, including those from the PKS, enrolled in the OLLI, receiving age-based, oral, once daily doses of baricitinib. Pts with a JIA-ACR30 response at wk12, end of OLLI, entered the DBW to be randomized 1:1 to continued baricitinib or newly started placebo (PBO) and remained until flare or up to wk32. Primary endpoint was time to flare during the DBW. Secondary endpoints included JIA-ACR30/50/70/90 response rates at wk12, and proportion of pts with a flare during the DBW. Survival curves were estimated using the Kaplan-Meier method.

Results

Of 220 pts enrolled, 29 participated in the PKS, 219 entered the OLLI, and 163 entered the DBW. The JIA-ACR30/50/70/90 response at wk12 was 76.3%/63.5%/46.1%/20.1%, respectively. During the DBW, time of flare was significantly shorter with PBO vs baricitinib (hazard ratio 0.24 [95% CI 0.13,0.45], p<0.001; Figure 1). The proportion of pts with a flare during the DBW was significantly lower for baricitinib vs PBO (14 (17.1%) vs. 41 (50.6%), p<0.001). In the PKS and OLLI periods, 126 (57.3%) pts reported ≥1 treatment emergent adverse event (TEAE), while 6 (2.7%) reported ≥1 serious adverse event (SAE); Table 1. In the DBW, 38 (46.9%) and 54 (65.9%) pts reported ≥1 TEAE for PBO and baricitinib, respectively, whereas those with ≥1 SAE were 3 (3.7%) and 4 (4.9%). The mean wks of exposure was higher in the baricitinib vs PBO group during DBW (26.34 vs 18.91) due to study design. There were no deaths, cardiovascular events or uveitis and 1 case of herpes zoster. Table 1.

Conclusion

Baricitinib significantly reduced time to and frequency of JIA flares in pts with JIA versus PBO, and improved JIA-ACR scores in the majority of pts within 12wks. Safety findings were consistent with the known safety profile in adult rheumatoid arthritis indications. These findings support baricitinib as a treatment for signs and symptoms of JIA with an inadequate response to cs or b-DMARDs.

References

[1]Giannini EH, et. al. Preliminary definition of improvement in juvenile arthritis. Arthritis Rheum 1997; 40: 1202-1209.

[2]Brunner HI, et. al. Preliminary definition of disease flare in juvenile rheumatoid arthritis. J Rheumatol 2002; 29(5):1058-64.

Disclosure of Interests

Athimalaipet Ramanan Consultant of: Eli Lilly and Company, Abbvie, Roche, UCB, Novartis, Pfizer, and Sobi, Grant/research support from: Eli Lilly and Company, Pierre Quartier Consultant of: Eli Lilly and Company, Abbvie, Amgen, BMS, Novartis, Novimmune, Pfizer, Swedish Orphan Biovitrum, SANOFI, Speakers bureau: Abbvie, Novartis, Pfizer, Swedish Orphan Biovitrum, Nami Okamoto Consultant of: Swedish Orphan Biovitrum, Eli Lilly and Company, Speakers bureau: AbbVie, Eli Lilly and Company, Sanofi, Asahi Kasei Medical, Mitsubishi Tanabe Pharma, Bristol Myers Squibb, Pfizer Japan, Ayumi Pharma, Eisai, Torii Pharma, GlaxoSmithKline, Kyorin Pharma, Novartis, Chugai Pharmaceutical, Teijin Pharma, Gabriella Meszaros Employee of: Eli Lilly and Company, Joana Araujo Employee of: Eli Lilly and Company, Zhongkai Wang Employee of: Eli Lilly and Company, Ran Liao Employee of: Eli Lilly and Company, Brenda Crowe Employee of: Eli Lilly and Company, Xin Zhang Employee of: Eli Lilly and Company, Rodney Decker Employee of: Eli Lilly and Company, Stuart Keller Employee of: Eli Lilly and Company, Hermine Brunner Consultant of: AbbVie, Astra Zeneca-Medimmune, Biogen, Boehringer, Bristol-Myers Squibb, Celgene, Eli Lilly, EMD Serono, Idorsia, Cerocor, Janssen, GlaxoSmithKline, F. Hoffmann-La Roche, Merck, Novartis, R-Pharm, Sanofi, Speakers bureau: Novartis, Pfizer, GlaxoSmithKline, Nicolino Ruperto Consultant of: Eli Lilly and Company, Ablynx, Amgen, Astrazeneca-Medimmune, Aurinia, Bayer, Bristol Myers and Squibb, Cambridge Healthcare Research (CHR), Celgene, Domain therapeutic, Eli-Lilly, EMD Serono, Glaxo Smith and Kline, Idorsia, Janssen, Novartis, Pfizer, Sobi, UCB, Speakers bureau: Eli Lilly and Company, Glaxo Smith and Kline, Pfizer, Sobi, UCB

Myocardial Composition in Light-Chain Cardiac Amyloidosis More Than 1 Year After Successful Therapy

OBJECTIVES

The goals of this study were to characterize myocardial composition during the active and remission phases of light-chain (AL) cardiac amyloidosis.

BACKGROUND

Cardiac dysfunction in AL amyloidosis is characterized by dual insults to the myocardium from infiltration and toxicity from light chains during the active phase and by infiltration alone in the remission phase.

METHODS

Prospectively enrolled subjects with cardiac AL amyloidosis (21 remission AL amyloidosis; age: 63.4 ± 7.3 years; 47.6% male; and 48 active AL amyloidosis; age: 62.5 ± 7.4 years; 60.4% male) underwent contrast-enhanced cardiac magnetic resonance with T1 and T2 mapping and measurement of extracellular volume (ECV). By definition, serum free light-chain levels were normal for at least 1 year following successful AL therapy in the remission group and abnormal in the active group.

RESULTS

Myocardial ECV was similarly expanded in the remission and active AL amyloidosis groups (0.488 ± 0.082 vs 0.519 ± 0.083, respectively; P = 0.15). However, myocardial T2 relaxation times (47.7 ± 3.2 ms vs 45.5 ± 3.0 ms; P = 0.008) as well as native T1 times (1,368 ms [IQR: 1,290-1,422 ms] vs 1,264 ms [IQR: 1,203-1,380 ms]; P = 0.024) were significantly higher in the remission compared to the active AL amyloidosis group.

CONCLUSIONS

Myocardial ECV is substantially expanded in the active AL and remission AL cardiac amyloidosis groups, but native T1 values were higher, suggesting a different myocardial composition. There is no evidence of myocardial edema in active AL cardiac amyloidosis. Future phenotyping studies of AL cardiac amyloidosis need to consider complementary myocardial markers that define the interstitial milieu in addition to changes in extracellular volume. (Molecular Imaging of Primary Amyloid Cardiomyopathy; NCT02641145).

[Correlation of peritumoral circWDR25 expression with the prognosis of patients with hepatocellular carcinoma after curative resection]

OBJECTIVE

To study the association between the expression of peritumoral circWDR25 (hsa-circRNA-0004310) secreted by hepatic stellate cells (HSCs) and the prognosis of the patients with hepatocellular carcinoma (HCC) after curative resection.

METHODS

HSCs cell line LX-2 was co-cultured separately with 3 liver cancer cell lines (Hep3B, SMMC-7721, and HCCLM3) in Transwell chambers to obtain tumor cell-activated HSCs. The supernatants of HSC cultures were collected to isolate the exosomes, from which total RNA was extracted to detect circRNA expression profile. We also collected specimens of paracancerous liver tissues from 288 HCC patients undergoing radical resection in our department from January, 2014 to October, 2015, and the expression levels of circWDR25 and α-SMA were detected with in situ hybridization. Log-rank test and Cox regression analysis were used for univariate and multivariate analysis of the factors affecting the patients' prognosis, respectively.

RESULTS

Gene expression profiling revealed that the expression of circWDR25 was the most obviously up-regulated in the exosomes isolated from tumor-activated LX-2 cells. The expression of peritumoral circWDR25 was positively correlated with HSCs adjacent to the cancer loci (r=0.156, P=0.008). Multivariate analysis showed that a preoperative AST level >36 g/L, multiple tumors, a tumor diameter >5 cm, HSC>70, and circWDR25>190 were independent risk factors affecting the overall survival of HCC patients after radical resection; a preoperative AST level >36 g/L, multiple tumors, a tumor diameter >5 cm, presence of tumor thrombus, HSC>70, and circWDR25>190 were all independent risk factors for tumor-free survival in patients with liver cancer.

CONCLUSION

Peritumoral circWDR25 and HSCs are factors affecting the prognosis of HCC patients after radical hepatectomy, and their high expression in the adjacent tissues is closely related to a poor prognosis of the patients.

Genome-wide CRISPR/Cas9 screening in human iPS derived cardiomyocytes uncovers novel mediators of doxorubicin cardiotoxicity

Human induced pluripotent stem (iPS) cell technologies coupled with genetic engineering now facilitate the study of the molecular underpinnings of disease in relevant human cell types. Application of CRISPR/Cas9-based approaches for genome-scale functional screening in iPS-derived cells, however, has been limited by technical constraints, including inefficient transduction in pooled format, loss of library representation, and poor cellular differentiation. Herein, we present optimized approaches for whole-genome CRISPR/Cas9 based screening in human iPS derived cardiomyocytes with near genome-wide representation at both the iPS and differentiated cell stages. As proof-of-concept, we perform a screen to investigate mechanisms underlying doxorubicin mediated cell death in iPS derived cardiomyocytes. We identified two poorly characterized, human-specific transporters (SLCO1A2, SLCO1B3) whose loss of function protects against doxorubicin-cardiotoxicity, but does not affect cell death in cancer cells. This study provides a technical framework for genome-wide functional screening in iPS derived cells and identifies new targets to mitigate doxorubicin-cardiotoxicity in humans.

MicroRNA-21 regulates right ventricular remodeling secondary to pulmonary arterial pressure overload

Right ventricular (RV) function is a critical determinant of survival in patients with pulmonary arterial hypertension (PAH). While miR-21 is known to associate with vascular remodeling in small animal models of PAH, its role in RV remodeling in large animal models has not been characterized. Herein, we investigated the role of miR-21 in RV dysfunction using a sheep model of PAH secondary to pulmonary arterial constriction (PAC). RV structural and functional remodeling were examined using ultrasound imaging. Our results showed that post PAC, RV strain significantly decreased at the basal region compared with t the control. Moreover, such dysfunction was accompanied by increases in miR-21 levels. To determine the role of miR-21 in RV remodeling secondary to PAC, we investigated the molecular alteration secondary to phenylephrine induced hypertrophy and miR21 overexpression in vitro using neonatal rat ventricular myocytes (NRVMs). We found that overexpression of miR-21 in the setting of hypertrophic stimulation augmented only the expression of proteins critical for mitosis but not cytokinesis. Strikingly, this molecular alteration was associated with an eccentric cellular hypertrophic phenotype similar to what we observed in vivo PAC animal model in sheep. Importantly, this hypertrophic change was diminished upon suppressing miR-21 in NRVMs. Collectively, our in vitro and in vivo data demonstrate that miR-21 is a critical contributor in the development of RV dysfunction and could represent a novel therapeutic target for PAH associated RV dysfunction.

Serum high-density lipoprotein cholesterol serves as a prognostic marker for light-chain cardiac amyloidosis

BACKGROUND

Oxidative stress and inflammation are central in the pathophysiology of light-chain amyloid cardiomyopathy (AL-CM). High-density lipoprotein cholesterol (HDLC) is an antioxidant and acts as an anti-inflammatory regulator. In this study, the prognostic value of serum HDL-C was explored in AL-CM.

METHOD

In this prospective single-center study, two hundred consecutive patients with biopsy-confirmed light-chain amyloidosis (AL) and cardiac involvement were enrolled. Patients were classified into low or normal serum HDL-C groups (HDL-C < 40 mg/dL and HDL-C ≥ 40 mg/dL, respectively). Univariate and multivariate Cox models were used to identify predictors of survival. Kaplan-Meier analysis was performed to compare survival between patients with low or normal serum HDL-C.

RESULTS

Patients with low serum HDL-C were more likely to present with higher levels of cardiac troponin-T (123.4 ng/L vs. 79.1 ng/L, p = 0.026) and higher levels of N-terminal pro-B-type natriuretic peptide (9146 pg/mL vs. 4945 pg/mL, p = 0.011). Patients were followed for a median follow-up period of 19 months, in which 118 (59%) patients died. The median overall survival times for patients with low or normal serum HDL-C were 7 and 16 months, respectively (p = 0.002). Multivariate analysis demonstrated that serum HDL-C (HR 0.984, 95% CI 0.973-0.994, p = 0.003) was independently associated with prognosis, after adjusting for nephrotic syndrome, hepatic involvement, nutritional state, renal function, SBP, DBP, serum uric acid, total cholesterol, Mayo AL 2004 stage, and treatment with chemotherapy.

CONCLUSIONS

HDL-C is a novel serum biomarker for disease severity and prognosis in light-chain cardiac amyloidosis.

Quantitative [18F]florbetapir PET/CT may identify lung involvement in patients with systemic AL amyloidosis

PURPOSE

The clinical diagnosis of pulmonary involvement in individuals with systemic AL amyloidosis remains challenging. [18F]florbetapir imaging has previously identified AL amyloid deposits in the heart and extra-cardiac organs. The aim of this study is to determine quantitative [18F]florbetapir pulmonary kinetics to identify pulmonary involvement in individuals with systemic AL amyloidosis.

METHODS

We prospectively enrolled 58 subjects with biopsy-proven AL amyloidosis and 9 control subjects (5 without amyloidosis and 4 with ATTR cardiac amyloidosis). Pulmonary [18F]florbetapir uptake was evaluated visually and quantified as distribution volume of specific binding (Vs) derived from compartmental analysis and simpler semiquantitative metrics of maximum standardized uptake values (SUVmax), retention index (RI), and target-to-blood ratio (TBR).

RESULTS

On visual analysis, pulmonary tracer uptake was absent in most AL subjects (40/58, 69%); 12% (7/58) of AL subjects demonstrated intense bilateral homogeneous tracer uptake. In this group, compared to the control group, Vs (median Vs 30-fold higher, 9.79 vs. 0.26, p < 0.001), TBR (median TBR 12.0 vs. 1.71, p < 0.001), and RI (median RI 0.310 vs. 0.033, p < 0.001) were substantially higher. Notably, the AL group without visually apparent pulmonary [18F]florbetapir uptake also demonstrated a > 3-fold higher Vs compared to the control group (median 0.99 vs. 0.26, p < 0.001). Vs was independently related to left ventricular SUVmax, a marker of cardiac AL deposition, but not to ejection fraction, a marker of cardiac dysfunction. Also, intense [18F]florbetapir lung uptake was not related to [11C]acetate lung uptake, suggesting that intense [18F]florbetapir lung uptake represents AL amyloidosis rather than heart failure.

CONCLUSIONS

[18F]florbetapir PET/CT offers the potential to noninvasively identify pulmonary AL amyloidosis, and its clinical relevance warrants further study.

Improved Quantification of Cardiac Amyloid Burden in Systemic Light Chain Amyloidosis: Redefining Early Disease?

OBJECTIVES

The purpose of this study was to determine phenotypes characterizing cardiac involvement in AL amyloidosis by using direct (fluorine-18-labeled florbetapir {[¹⁸F]florbetapir} positron emission tomography [PET]/computed tomography) and indirect (echocardiography and cardiac magnetic resonance [CMR]) imaging biomarkers of AL amyloidosis.

BACKGROUND

Cardiac involvement in systemic light chain amyloidosis (AL) is the main determinant of prognosis and, therefore, guides management. The hypothesis of this study was that myocardial AL deposits and expansion of extracellular volume (ECV) could be identified before increases in N-terminal pro-B-type natriuretic peptide or wall thickness.

METHODS

A total of 45 subjects were prospectively enrolled in 3 groups: 25 with active AL amyloidosis with cardiac involvement (active-CA), 10 with active AL amyloidosis without cardiac involvement by conventional criteria (active-non-CA), and 10 with AL amyloidosis with cardiac involvement in remission for at least 1 year (remission-CA). All subjects underwent echocardiography, CMR, and [¹⁸F]florbetapir PET/CT to evaluate cardiac amyloid burden.

RESULTS

The active-CA group demonstrated the largest myocardial AL amyloid burden, quantified by [¹⁸F]florbetapir retention index (RI) 0.110 (interquartile range [IQR]: 0.078 to 0.139) min^-1, and the lowest cardiac function by global longitudinal strain (GLS), median GLS -11% (IQR: -8% to -13%). The remission-CA group had expanded extracellular volume (ECV) and [¹⁸F]florbetapir RI of 0.097 (IQR: 0.070 to 0.124 min^-1), and abnormal GLS despite hematologic remission for >1 year. The active-non-CA cohort had evidence of cardiac amyloid deposition by advanced imaging metrics in 50% of the subjects; cardiac involvement was identified by late gadolinium enhancement in 20%, elevated ECV in 20%, and elevated [¹⁸F]florbetapir RI in 50%.

CONCLUSIONS

Evidence of cardiac amyloid infiltration was found based on direct and indirect imaging biomarkers in subjects without CA by conventional criteria. The findings from [¹⁸F]florbetapir PET imaging provided insight into the preclinical disease process and on the basis of interpretation of expanded ECV on CMR and have important implications for future research and clinical management of AL amyloidosis. (Molecular Imaging of Primary Amyloid Cardiomyopathy [MICA]; NCT02641145).

Localized Antileptin Therapy Prevents Aortic Root Dilatation and Preserves Left Ventricular Systolic Function in a Murine Model of Marfan Syndrome

Background Marfan syndrome (MFS) is a genetically transmitted connective tissue disorder characterized by aortic root dilatation, dissection, and rupture. Molecularly, MFS pathological features have been shown to be driven by increased angiotensin II in the aortic wall. Using an angiotensin II-driven aneurysm mouse model, we have recently demonstrated that local inhibition of leptin activity restricts aneurysm formation in the ascending and abdominal aorta. As we observed de novo leptin synthesis in the ascending aortic aneurysm wall of patients with MFS, we hypothesized that local counteracting of leptin activity in MFS may also prevent aortic cardiovascular complications in this context. Methods and Results Fbn1^C1039G/+ mice underwent periaortic application of low-dose leptin antagonist at the aortic root. Treatment abolished medial degeneration and prevented increase in aortic root diameter (P<0.001). High levels of leptin, transforming growth factor β1, Phosphorylated Small mothers against decapentaplegic 2, and angiotensin-converting enzyme 1 observed in saline-treated MFS mice were downregulated in leptin antagonist-treated animals (P<0.01, P<0.05, P<0.001, and P<0.001, respectively). Leptin and angiotensin-converting enzyme 1 expression levels in left ventricular cardiomyocytes were also decreased (P<0.001) and coincided with prevention of left ventricular hypertrophy and aortic and mitral valve leaflet thickening (P<0.01 and P<0.05, respectively) and systolic function preservation. Conclusions Local, periaortic application of leptin antagonist prevented aortic root dilatation and left ventricular valve remodeling, preserving left ventricular systolic function in an MFS mouse model. Our results suggest that local inhibition of leptin may constitute a novel, stand-alone approach to prevent MFS aortic root aneurysms and potentially other similar angiotensin II-driven aortic pathological features.

High-Frequency Ultrasound Echocardiography to Assess Zebrafish Cardiac Function

The zebrafish (Danio rerio) has become a very popular model organism in cardiovascular research, including human cardiac diseases, largely due to its embryonic transparency, genetic tractability, and amenity to rapid, high-throughput studies. However, the loss of transparency limits heart function analysis at the adult stage, which complicates modeling of age-related heart conditions. To overcome such limitations, high-frequency ultrasound echocardiography in zebrafish is emerging as a viable option. Here, we present a detailed protocol to assess cardiac function in adult zebrafish by non-invasive echocardiography using high-frequency ultrasound. The method allows visualization and analysis of zebrafish heart dimension and quantification of important functional parameters, including heart rate, stroke volume, cardiac output, and ejection fraction. In this method, the fish are anesthetized and kept underwater and can be recovered after the procedure. Although high-frequency ultrasound is an expensive technology, the same imaging platform can be used for different species (e.g., murine and zebrafish) by adapting different transducers. Zebrafish echocardiography is a robust method for cardiac phenotyping, useful in the validation and characterization of disease models, particularly late-onset diseases; drug screens; and studies of heart injury, recovery, and regenerative capacity.

Natural Compound Library Screening Identifies New Molecules for the Treatment of Cardiac Fibrosis and Diastolic Dysfunction

BACKGROUND

Myocardial fibrosis is a hallmark of cardiac remodeling and functionally involved in heart failure development, a leading cause of deaths worldwide. Clinically, no therapeutic strategy is available that specifically attenuates maladaptive responses of cardiac fibroblasts, the effector cells of fibrosis in the heart. Therefore, our aim was to develop novel antifibrotic therapeutics based on naturally derived substance library screens for the treatment of cardiac fibrosis.

METHODS

Antifibrotic drug candidates were identified by functional screening of 480 chemically diverse natural compounds in primary human cardiac fibroblasts, subsequent validation, and mechanistic in vitro and in vivo studies. Hits were analyzed for dose-dependent inhibition of proliferation of human cardiac fibroblasts, modulation of apoptosis, and extracellular matrix expression. In vitro findings were confirmed in vivo with an angiotensin II-mediated murine model of cardiac fibrosis in both preventive and therapeutic settings, as well as in the Dahl salt-sensitive rat model. To investigate the mechanism underlying the antifibrotic potential of the lead compounds, treatment-dependent changes in the noncoding RNAome in primary human cardiac fibroblasts were analyzed by RNA deep sequencing.

RESULTS

High-throughput natural compound library screening identified 15 substances with antiproliferative effects in human cardiac fibroblasts. Using multiple in vitro fibrosis assays and stringent selection algorithms, we identified the steroid bufalin (from Chinese toad venom) and the alkaloid lycorine (from Amaryllidaceae species) to be effective antifibrotic molecules both in vitro and in vivo, leading to improvement in diastolic function in 2 hypertension-dependent rodent models of cardiac fibrosis. Administration at effective doses did not change plasma damage markers or the morphology of kidney and liver, providing the first toxicological safety data. Using next-generation sequencing, we identified the conserved microRNA 671-5p and downstream the antifibrotic selenoprotein P1 as common effectors of the antifibrotic compounds.

CONCLUSIONS

We identified the molecules bufalin and lycorine as drug candidates for therapeutic applications in cardiac fibrosis and diastolic dysfunction.

Impaired bone microarchitecture in distal interphalangeal joints in patients with primary hypertrophic osteoarthropathy assessed by high-resolution peripheral quantitative computed tomography

This study aimed to investigate the bone impairment in finger joints in PHO patients by HR-pQCT. Results showed distinguished differences in bone architecture and biomechanics parameters at DIPs between PHO patients and healthy controls using HR-pQCT assessment. Besides, serum PGE2, hsCRP and ESR levels were found negatively correlated with total vBMD.

INTRODUCTION

This study aimed to investigate the bone impairment in finger joints in primary hypertrophic osteoarthropathy (PHO) patients firstly by high-resolution peripheral quantitative computed tomography (HR-pQCT).

METHODS

Fifteen PHO patients and 15 healthy controls were enrolled in this study. Bone erosions in hands at distal interphalangeal joints (DIPs) in both PHO patients and controls were evaluated by X-ray. Bone geometry, vBMD, microstructure parameters, and size of individual bone erosion were also measured at the 3rd DIP by HR-pQCT as well. Blood biochemistry levels between the two groups were also compared.

RESULTS

Compared to X-ray, HR-pQCT assessment were more sensitive for detection of bone erosions, with 14 PHO patients by HR-pQCT versus ten PHO patients by X-ray judged at the 3rd DIP. The average depth, width, and volume of erosions size in PHO patients were 1.38 ± 0.80 mm, 0.79 ± 0.27 mm, and 1.71 ± 0.52 mm³, respectively. The bone cross-areas including total area (+ 25.3%, p ≤ 0.05), trabecular area (+ 56.2%, p ≤ 0.05), and cortical perimeter (+ 10.7%, p ≤ 0.05) at the defined region of interest of 3rd DIP was significantly larger than controls. Total vBMD was 11.9% lower in PHO patients compared with the controls (p ≤ 0.05). Biochemical test results showed the increased levels of inflammatory cytokines, bone resorption markers, and joint degeneration markers in PHO patients. Serum prostaglandin PGE2, high-sensitive C-reactive protein (hsCRP) and erythrocyte sedimentation rate (ESR) levels were found negatively correlated with total vBMD.

CONCLUSIONS

This study demonstrated higher sensitivity of the HR-pQCT measurement at DIPs by showing the differences in architecture and biomechanics parameters at DIPs between the PHO patients and healthy controls, which would be of interest clinically to investigate bone deterioration in PHO patients.

Effects of miR-155 on hypertensive rats via regulating vascular mesangial hyperplasia

OBJECTIVE

Vascular smooth muscle cell (VSMC) excessive proliferation is related to hypertension. The cell cycle inhibitory factor (p27) can arrest cell cycle, while its down-regulation is associated with hypertension. It is found that microRNA-155 (miR-155) plays a regulatory role in VSMC proliferation, while its relationship with hypertension is still unclear. Bioinformatics analysis reveals the targeted relationship between miR-155 and the 3'-UTR of p27 mRNA. This study aims to explore the role of miR-155 in regulating p27 expression, VSMC proliferation and apoptosis, and the pathogenesis of hypertension.

MATERIALS AND METHODS

Dual luciferase reporter gene assay confirmed the relationship between miR-155 and p27. MiR-155, p27, α-smooth muscle actin (α-SMA), and Ki-67 expressions in the thoracic aorta media of rat hypertension model were detected. VSMCs were cultured in vitro and divided into five groups, including anti-miR-NC, anti-miR-155, pIRES2-blank, pIRES2-p27, and anti-miR-155 + pIRES2-p27 groups. Cell cycle was evaluated by using flow cytometry. Cell proliferation was detected with EdU staining. Hypertension rats were randomly divided into antagomir-155 and antagomir-control. Caudal artery systolic and diastolic pressures were measured.

RESULTS

MiR-155 targeted suppressed p27 expression. MiR-155 and Ki-67 expressions significantly enhanced, while p27 and α-SMA levels reduced in the tunica media from hypertension rats compared with control. Down-regulation of miR-155 and/or up-regulation of p27significantly declined cell proliferation and arrested cell cycle in G1 phase. Antagomir-155 injection markedly decreased systolic and diastolic pressures, elevated p27 and α-SMA expressions in media, and reduced the thickness of tunica media.

CONCLUSIONS

MiR-155 promoted VSMC proliferation by targeting p27. MiR-155 enhancement was related to hypertension. MiR-155 played a therapeutic effect on hypertension.

Convergences of Life Sciences and Engineering in Understanding and Treating Heart Failure

On March 1 and 2, 2018, the National Institutes of Health 2018 Progenitor Cell Translational Consortium, Cardiovascular Bioengineering Symposium, was held at the University of Alabama at Birmingham. Convergence of life sciences and engineering to advance the understanding and treatment of heart failure was the theme of the meeting. Over 150 attendees were present, and >40 scientists presented their latest work on engineering human functional myocardium for disease modeling, drug development, and heart failure research. The scientists, engineers, and physicians in the field of cardiovascular sciences met and discussed the most recent advances in their work and proposed future strategies for overcoming the major roadblocks of cardiovascular bioengineering and therapy. Particular emphasis was given for manipulation and using of stem/progenitor cells, biomaterials, and methods to provide molecular, chemical, and mechanical cues to cells to influence their identity and fate in vitro and in vivo. Collectively, these works are profoundly impacting and progressing toward deciphering the mechanisms and developing novel treatments for left ventricular dysfunction of failing hearts. Here, we present some important perspectives that emerged from this meeting.

Geographic Disparities in Reported US Amyloidosis Mortality From 1979 to 2015: Potential Underdetection of Cardiac Amyloidosis

Importance

Cardiac amyloidosis is an underdiagnosed disease and is highly fatal when untreated. Early diagnosis and treatment with the emerging novel therapies significantly improve survival. A comprehensive analysis of amyloidosis-related mortality is critical to appreciate the nature and distribution of underdiagnosis and improve disease detection.

Objective

To evaluate the temporal and regional trends in age-adjusted amyloidosis-related mortality among men and women of various races/ethnicities in the United States.

Design, Setting, and Participants

In this observational cohort study, death certificate information from the Centers for Disease Control and Prevention's Wide-ranging ONline Data for Epidemiologic Research database and the National Vital Statistics System from 1979 to 2015 was analyzed. A total of 30 764 individuals in the United States with amyloidosis listed as the underlying cause of death and 26 591 individuals with amyloidosis listed as a contributing cause of death were analyzed.

Exposures

Region of residence.

Main Outcomes and Measures

Age-adjusted mortality rate from amyloidosis per 1 000 000 population stratified by year, sex, race/ethnicity, and state and county of residence.

Results

Of the 30 764 individuals with amyloidosis listed as the underlying cause of death, 17 421 (56.6%) were men and 27 312 (88.8%) were 55 years or older. From 1979 to 2015, the reported overall mean age-adjusted mortality rate from amyloidosis as the underlying cause of death doubled from 1.77 to 3.96 per 1 000 000 population (2.32 to 5.43 in men and 1.35 to 2.80 in women). Black men had the highest mortality rate (12.36 per 1 000 000), followed by black women (6.48 per 1 000 000). Amyloidosis contributed to age-adjusted mortality rates as high as 31.73 per 1 000 000 in certain counties. Most southern states reported the lowest US mortality rates despite having the highest proportions of black individuals.

Conclusions and Relevance

The increased reported mortality over time and in proximity to amyloidosis centers more likely reflects an overall increase in disease diagnosis rather than increased lethality. The reported amyloidosis mortality is highly variable in different US regions. The lack of higher reported mortality rates in states with a greater proportion of black residents suggests underdiagnosis of amyloidosis, including cardiac forms of the disease, in many areas of the United States. Better understanding of the determinants of geographic and racial disparity in the reporting of amyloidosis deaths are warranted.

Alteration in ventricular pressure stimulates cardiac repair and remodeling

The mammalian heart undergoes complex structural and functional remodeling to compensate for stresses such as pressure overload. While studies suggest that, at best, the adult mammalian heart is capable of very limited regeneration arising from the proliferation of existing cardiomyocytes, how myocardial stress affects endogenous cardiac regeneration or repair is unknown. To define the relationship between left ventricular afterload and cardiac repair, we induced left ventricle pressure overload in adult mice by constriction of the ascending aorta (AAC). One week following AAC, we normalized ventricular afterload in a subset of animals through removal of the aortic constriction (de-AAC). Subsequent monitoring of cardiomyocyte cell cycle activity via thymidine analog labeling revealed that an acute increase in ventricular afterload induced cardiomyocyte proliferation. Intriguingly, a release in ventricular overload (de-AAC) further increases cardiomyocyte proliferation. Following both AAC and de-AAC, thymidine analog-positive cardiomyocytes exhibited characteristics of newly generated cardiomyocytes, including single diploid nuclei and reduced cell size as compared to age-matched, sham-operated adult mouse myocytes. Notably, those smaller cardiomyocytes frequently resided alongside one another, consistent with local stimulation of cellular proliferation. Collectively, our data demonstrate that adult cardiomyocyte proliferation can be locally stimulated by an acute increase or decrease of ventricular pressure, and this mode of stimulation can be harnessed to promote cardiac repair.

Zebrafish model of amyloid light chain cardiotoxicity: regeneration versus degeneration

Cardiac dysfunction is the most frequent cause of morbidity and mortality in amyloid light chain (AL) amyloidosis caused by a clonal immunoglobulin light chain (LC). Previously published transgenic animal models of AL amyloidosis have not recapitulated the key phenotype of cardiac dysfunction seen in AL amyloidosis, which has limited our understanding of the disease mechanisms in vivo, as well as the development of targeted AL therapeutics. We have developed a transgenic zebrafish model in which a λ LC derived from a patient with AL amyloidosis is conditionally expressed in the liver under the control of the Gal4 upstream activation sequence enhancer system. Circulating LC levels of 125 µg/ml in these transgenic zebrafish are comparable to median pathological serum LC levels. Functional analysis links abnormal contractile function with evidence of cellular and molecular proteotoxicity in the heart, including increased cell death and autophagy. However, despite pathological and functional phenotypes analogous to human AL, the lifespan of the transgenic fish is comparable to control fish without the expressed AL-LC transgene. Nuclear labeling experiments suggest increased cardiac proliferation in the transgenic fish, which can be counteracted by treatment with a small molecule proliferation inhibitor leading to increased zebrafish mortality because of cardiac apoptosis and functional deterioration. This transgenic zebrafish model provides a platform to study underlying AL disease mechanisms in vivo further. NEW & NOTEWORTHY Heart failure is a major cause of mortality in amyloid light (AL) amyloidosis, yet it has been difficult to model in animals. We report the generation of a transgenic zebrafish model for AL amyloidosis with pathological concentration of circulating human light chain protein that results in cardiac dysfunction. The light chain toxicity triggers regeneration in the zebrafish heart resulting in functional compensation early in life, but with age develops into cardiac dysfunction.

[Expression and significance of programmed cell death ligand-1 in neuroblastoma tissues]

Objective: To investigate the relationship between expression of programmed cell death ligand-1(PD-L1) in the tissue of neuroblastoma (NB) and patient's clinical characteristics and prognosis. Methods: Clinical data and surgical tissue paraffin blocks of 100 newly diagnosed NB children at Sun Yat-sen University Cancer Center between January 2000 and December 2015 were collected and the expression level of PD-L1 and its' relationship with pathological parameters and survival rate were analyzed retrospectively. The ratio between groups was compared by chi-square test. Kaplan-Meier method was used for survival analysis and COX regression model was used for multivariate analysis. Results: Among 100 cases, 71 were males and 29 females; there were 5 cases of stageⅠ, 4 cases of stageⅡ, 19 cases of stage Ⅲ, 65 cases of stage Ⅳ and 7 cases of stage Ⅳs. Ten out of 62 cases (16%) were N-MYC amplified; 15 cases were in low-risk group, 18 were in medium-risk group and 67 were in high-risk group. The positive rate of PD-L1 in NB tumor tissue was 57% (57/100), of which 55 were weakly positive, 1 was moderately positive and 1 was strongly positive. The positive rates of PD-L1 expression in tumor tissues without bone metastasis were higher than those with bone metastasis(66%(39/59)vs.44%(18/41), χ(2)=4.864, P=0.027), the positive rates of PD-L1 expression in tumor tissues pathologically diagnosed as neuroblastoma were higher than those pathologically diagnosed as ganglioneuroblastoma (61%(53/87) vs.31%(4/13), χ(2)=4.195, P=0.041), the positive rates of PD-L1 expression in tumor tissues originated from abdominal cavity were higher than those originated from other places (61% (51/83)vs.35%(6/17), χ(2)=3.937,P=0.047).The 4-year event-free survival (EFS) rates of patients with PD-L1 negative and positive were 40% and 33% (χ(2)=0.009, P=0.923), respectively. The 4-year overall survival (OS) rates of patients with PD-L1 negative and positive were 62% and 58% (χ(2)=0.294, P=0.587). Among 33 non-high-risk patients, the 4-year EFS rates of patients with PD-L1 negative and positive were 89% and 78% (χ(2)=0.001, P=0.965), the 4-year OS rates of patients with PD-L1 negative and positive were 100% and 96% (χ(2)=0.500, P=0.480). Among 67 high-risk patients, the 4-year EFS rates of patients with PD-L1 negative and positive were 24% and 11% (χ(2)=1.154, P=0.282), the 4-year OS rates of patients with PD-L1 negative and positive were 48% and 41% (χ(2)=0.692, P=0.405). Multivariate analysis showed that N-MYC gene amplification was an independent adverse prognostic factor for OS and EFS rates of NB patients (RR: 1.726,95%CI:1.209-2.466; RR:1.326,95%CI:1.014-1.736) and advanced clinical stage was an independent adverse prognostic factor for EFS rates of NB patients (RR: 26.498, 95%CI:3.518-199.614). Conclusions: The expression of PD-L1 in NB tumor tissues was correlated with the clinical characteristics of children. However, there were no significant differences in the prognosis of patients with or without PD-L1 expression.

[The study of nomogram based on Ishak inflammation score for recurrence of hepatocellular carcinoma after curative resection]

Objective: To investigate the correlation between Ishak inflammation score and the clinicopathological characteristics and recurrence of patients with hepatocellular carcinoma (HCC) after curative resection, and then set up a recurrence nomogram for HCC. Methods: A total of 326 patients with HCC after curative resection from January 2006 to December 2009 were studied retrospectively as training cohort and 110 HCC patients after surgery from January 2010 to December 2012 were used as validation cohort.Clinical follow-up data and peritumoral Ishak inflammation score in training cohort were used to set up a nomogram predicting recurrence of HCC, which was verified by validation cohort. Kaplan-Meier and Cox proportional hazard regression model were used to analyzed accuracy of model prediction. Results: According to Ishak inflammation score, patients were divided into four subgroups: Grade Ⅰ(1-4 scores), Grade Ⅱ(5-8 scores), Grade Ⅲ (9-12 scores) and Grade Ⅳ(13-18 scores). Ishak inflammation score were associated with aspartate transaminase(median 36.0 U/L, P=0.011), γ-glutamyl transpeptidase(median 54.5 U/L, P=0.005), HBV-DNA load(20.5%>10(6) copies/ml, P=0.015) and microvascular invasion(26.7% positive, P=0.021). Multivariate analysis showed that Ishak inflammation score(P=0.007), HBV-DNA load(P<0.01), tumor size(P=0.001) and microvascular invasion(P=0.001) were related with the recurrence of HCC patients.These four risk factors were incorporated into the nomogram.Calibration curves of the nomogram had good agreement between prediction and observation in the probability of recurrence.Both C-indexes and receiver operating characteristic curve analyses revealed that this nomogram had better predictive abilities than those of the AJCC and Barcelona Clinic Liver Cancer (BCLC) stage systems.These results were verified by the validation cohort. Conclusion: A nomogram based on Ishak inflammation score could accurately predict the recurrence of HCC and contribute to HCC relapse surveillance after curative hepatectomy.

Cardiac macrophages promote diastolic dysfunction

Hulsmans et al. show that cardiac macrophages expand in left ventricular diastolic dysfunction, a hallmark of heart failure with preserved ejection fraction (HFpEF) and cardiac aging. In HFpEF, macrophages shift toward a profibrotic subset that promotes ventricular stiffness.

Macrophages populate the healthy myocardium and, depending on their phenotype, may contribute to tissue homeostasis or disease. Their origin and role in diastolic dysfunction, a hallmark of cardiac aging and heart failure with preserved ejection fraction, remain unclear. Here we show that cardiac macrophages expand in humans and mice with diastolic dysfunction, which in mice was induced by either hypertension or advanced age. A higher murine myocardial macrophage density results from monocyte recruitment and increased hematopoiesis in bone marrow and spleen. In humans, we observed a parallel constellation of hematopoietic activation: circulating myeloid cells are more frequent, and splenic ¹⁸F-FDG PET/CT imaging signal correlates with echocardiographic indices of diastolic dysfunction. While diastolic dysfunction develops, cardiac macrophages produce IL-10, activate fibroblasts, and stimulate collagen deposition, leading to impaired myocardial relaxation and increased myocardial stiffness. Deletion of IL-10 in macrophages improves diastolic function. These data imply expansion and phenotypic changes of cardiac macrophages as therapeutic targets for cardiac fibrosis leading to diastolic dysfunction.

Guidelines for experimental models of myocardial ischemia and infarction

Myocardial infarction is a prevalent major cardiovascular event that arises from myocardial ischemia with or without reperfusion, and basic and translational research is needed to better understand its underlying mechanisms and consequences for cardiac structure and function. Ischemia underlies a broad range of clinical scenarios ranging from angina to hibernation to permanent occlusion, and while reperfusion is mandatory for salvage from ischemic injury, reperfusion also inflicts injury on its own. In this consensus statement, we present recommendations for animal models of myocardial ischemia and infarction. With increasing awareness of the need for rigor and reproducibility in designing and performing scientific research to ensure validation of results, the goal of this review is to provide best practice information regarding myocardial ischemia-reperfusion and infarction models.

Listen to this article’s corresponding podcast at ajpheart.podbean.com/e/guidelines-for-experimental-models-of-myocardial-ischemia-and-infarction/.

AL (Light-Chain) Cardiac Amyloidosis: A Review of Diagnosis and Therapy

The amyloidoses are a group of protein-folding disorders in which ≥1 organ is infiltrated by proteinaceous deposits known as amyloid. The deposits are derived from 1 of several amyloidogenic precursor proteins, and the prognosis of the disease is determined both by the organ(s) involved and the type of amyloid. Amyloid involvement of the heart (cardiac amyloidosis) carries the worst prognosis of any involved organ, and light-chain (AL) amyloidosis is the most serious form of the disease. The last decade has seen considerable progress in understanding the amyloidoses. In this review, current and novel approaches to the diagnosis and treatment of cardiac amyloidosis are discussed, with particular reference to AL amyloidosis in the heart.

Simultaneous electrical recording of cardiac electrophysiology and contraction on chip

Prevailing commercialized cardiac platforms for in vitro drug development utilize planar microelectrode arrays to map action potentials, or impedance sensing to record contraction in real time, but cannot record both functions on the same chip with high spatial resolution. Here we report a novel cardiac platform that can record cardiac tissue adhesion, electrophysiology, and contractility on the same chip. The platform integrates two independent yet interpenetrating sensor arrays: a microelectrode array for field potential readouts and an interdigitated electrode array for impedance readouts. Together, these arrays provide real-time, non-invasive data acquisition of both cardiac electrophysiology and contractility under physiological conditions and under drug stimuli. Human induced pluripotent stem cell-derived cardiomyocytes were cultured as a model system, and used to validate the platform with an excitation-contraction decoupling chemical. Preliminary data using the platform to investigate the effect of the drug norepinephrine are combined with computational efforts. This platform provides a quantitative and predictive assay system that can potentially be used for comprehensive assessment of cardiac toxicity earlier in the drug discovery process.