Prognostic value of right ventricular global longitudinal strain in patients with immunoglobulin light-chain cardiac amyloidosis.

Aims: Left ventricular (LV) global longitudinal strain (GLS) (LV-GLS) is a strong and independent predictor of outcomes in patients with immunoglobulin light-chain (AL) cardiac amyloidosis. This study was performed to investigate whether right ventricular (RV) GLS (RV-GLS) provides prognostic information in patients with AL amyloidosis. Methods and results: Among 74 patients who were diagnosed with AL cardiac amyloidosis at Kumamoto University Hospital from December 2005 to December 2022, 65 patients who had enough information for two-dimensional speckle tracking imaging and did not receive chemotherapy before the diagnosis of cardiac amyloidosis were retrospectively analysed. During a median follow-up of 359 days, 29 deaths occurred. In two-dimensional echocardiographic findings, LV-GLS, left atrium reservoir strain (LASr), and RV-GLS were significantly lower in the all-cause death group than in the survival group (LV-GLS: 8.9 ± 4.2 vs. 11.7 ± 3.9, P < 0.01; LASr: 9.06 ± 7.28 vs. 14.09 ± 8.32, P < 0.05; RV-GLS: 12.0 ± 5.1 vs. 16.8 ± 4.0, P < 0.01). Multivariable Cox proportional hazard analysis showed RV-GLS was significantly and independently associated with all-cause death in patients with AL cardiac amyloidosis (hazard ratio 0.85; 95% confidence interval, 0.77-0.94; P < 0.01). Receiver operating characteristic analysis showed that the area under the curve of RV-GLS for all-cause death was 0.774 and that the best cut-off value of RV-GLS was 14.5% (sensitivity, 75%; specificity, 72%). In the Kaplan-Meier analysis, patients with AL cardiac amyloidosis who had low RV-GLS (<14.5%) had a significantly higher probability of all-cause death (P < 0.01). Conclusion: RV-GLS has prognostic value in patients with AL cardiac amyloidosis and provides greater prognostic power than LV-GLS and LASr.

Time-dependent change of relative apical longitudinal strain index in patients with wild-type transthyretin amyloid cardiomyopathy.

Aim: This study was conducted to investigate the meaning of left ventricular (LV) apical sparing in patients with wild-type transthyretin amyloid cardiomyopathy (ATTRwt-CM). Methods and results: 165 patients who were diagnosed with ATTRwt-CM at Kumamoto University Hospital from January 2002 to December 2020 and had sufficient data for two-dimensional speckle tracking echocardiography were enrolled. Of these, 86 patients (52 %) had LV apical sparing (relative apical longitudinal strain index (RapLSI) > 1.0). Multivariable logistic regression analysis revealed the following variables were significantly associated with LV apical sparing: interventricular septal thickness in diastole (odds ratio (OR), 1.19; 95 % confidence interval (CI), 1.01-1.41; p < 0.05); E/e' ratio (OR, 1.06; 95 % CI, 1.00-1.11; p < 0.05); and heart-to-contralateral ratio by 99mTc-labeled pyrophosphate scintigraphy (OR, 3.40; 95 % CI, 1.07-10.83; p < 0.05).Next, we compared RapLSI at the time of diagnosis with that during the follow-up period (396 days (346-458) after diagnosis) in 92 patients. RapLSI increased significantly during the follow-up period compared with RapLSI at diagnosis in the non-LV apical sparing group (0.89 ± 0.32 vs 0.74 ± 0.18, p < 0.01) but not in the LV apical sparing group (1.33 ± 0.53 vs 1.39 ± 0.45, p = 0.46). A total of 12 patients (29 %) in the non-LV apical sparing group developed LV apical sparing and 11 patients (22 %) in LV apical sparing group diminished LV apical sparing during the follow-up period. Conclusion: Approximately half of ATTRwt-CM patients did not have LV apical sparing at diagnosis. Because RapLSI in ATTRwt-CM significantly changed over time, repeated two-dimensional speckle tracking analysis is important for suspected ATTR-CM patients.

Elevated C-reactive protein is significantly associated with left ventricular dysfunction in patients with aortic regurgitation and concomitant collagen disease.

BACKGROUND: Collagen disease is an important cause of aortic regurgitation (AR). Although aortic valve surgery is recommended for patients with AR and depressed left ventricular (LV) function, there have been few reports about risk factors for LV dysfunction in patients with AR concomitant with collagen disease. METHODS AND RESULTS: We conducted this study at Kumamoto University Hospital in Japan. A total of 41 patients who had moderate to severe AR and concomitant collagen disease between January 2014 and December 2019 were enrolled. With regard to baseline characteristics, there were no significant differences in the type of collagen disease or El Khoury class between patients with preserved LV function and those with reduced LV function. B-type natriuretic peptide (375.2 [257.9-3852.6]pg/ml vs. 64.0 [33.3-133.6]pg/ml, p < 0.01), C-reactive protein (CRP) levels (2.00 [1.24-9.14]mg/dl vs. 0.19 [0.06-0.52]mg/dl, p < 0.01) and neutrophil-to-lymphocyte ratio (7.94 [3.30-9.98] vs. 3.94 [1.83-5.58], p < 0.05) were significantly higher, and hemoglobin level (10.7 ± 1.6 g/dl vs. 12.2 ± 1.8 g/dl, p < 0.05) was significantly lower in patients with reduced LV function than in those with preserved LV function. There were no significant differences in any variables associated with severity and features of AR. Multivariable logistic regression analysis showed that high CRP levels (≥1.0 mg/dl) were independently and significantly associated with LV dysfunction in patients with AR and collagen disease, even after adjusting for the severity of AR (odds ratio: 95.7; 95% confidence interval: 4.6-1990.4, p < 0.01). CONCLUSIONS: Uncontrolled inflammation, represented as high CRP levels, is an important marker for LV dysfunction in patients with AR and collagen disease.

(-)-Xanthatin up-regulation of the GADD45γ tumor suppressor gene in MDA-MB-231 breast cancer cells: role of topoisomerase IIα inhibition and reactive oxygen species.

Previously, we reported that (-)-xanthatin, a naturally occurring xanthanolide present in the Cocklebur plant, exhibits potent anti-proliferative effects on human breast cancer cells, accompanied by an induction of the growth arrest and DNA damage-inducible gene 45γ (GADD45γ), recognized recently as a novel tumor suppressor gene. However, the mechanisms mediating this activation were unknown. Topoisomerase IIα (Topo IIα) inhibition has been reported to produce a cell death response accompanied by an atypical DNA laddering fragmentation profile, similar to that noted previously for (-)-xanthatin. Therefore we hypothesized that (-)-xanthatin's GADD45γ activation was mediated through the Topo IIα pathway. Here, we identify that (-)-xanthatin does function as a catalytic inhibitor of Topo IIα, promoting DNA damage. In addition, reactive oxygen species (ROS) were elevated in cells treated with this agent. Mechanistically, it was determined that the induced levels of GADD45γ mRNA resulting from (-)-xanthatin exposures were stabilized by coordinately produced ROS, and that the consequent induction of GADD45γ mRNA, GADD45γ protein and ROS generation were abrogated by co-treatment with N-acetyl-l-cysteine. Taken together, the data support the concept that Topo IIα inhibition by (-)-xanthatin is a trigger that stimulates expression of DNA damage-inducible GADD45γ mRNA and that concomitantly produced ROS act downstream to further enhance the GADD45γ mRNA/GADD45γ protein induction process, resulting in breast cancer cell death.

Cannabidiol-2',6'-dimethyl ether as an effective protector of 15-lipoxygenase-mediated low-density lipoprotein oxidation in vitro.

15-Lipoxygenase (15-LOX) is one of the key enzymes responsible for the formation of oxidized low-density lipoprotein (ox-LDL), a major causal factor for atherosclerosis. Both enzymatic (15-LOX) and non-enzymatic (Cu(2+)) mechanisms have been proposed for the production of ox-LDL. We have recently reported that cannabidiol-2',6'-dimethyl ether (CBDD) is a selective and potent inhibitor of 15-LOX-catalyzed linoleic acid oxygenation (Takeda et al., Drug Metab. Dispos., 37, 1733-1737 (2009)). In the LDL, linoleic acid is present as cholesteryl linoleate, the major fatty acid esterified to cholesterol, and is susceptible to oxidative modification by 15-LOX or Cu(2+). In this investigation, we examined the efficacy of CBDD on i) 15-LOX-catalyzed oxygenation of cholesteryl linoleate, and ii) ox-LDL formation catalyzed by 15-LOX versus Cu(2+)-mediated non-enzymatic generation of this important mediator. The results obtained demonstrate that CBDD is a potent and selective inhibitor of ox-LDL formation generated by the 15-LOX pathway. These studies establish CBDD as both an important experimental tool for characterizing 15-LOX-mediated ox-LDL formation, and as a potentially useful therapeutic agent for treatment of atherosclerosis.