COX-2 optimizes cardiac mitochondrial biogenesis and exerts a cardioprotective effect during sepsis.

BACKGROUND: Septic cardiomyopathy is a component of multiple organ dysfunction in sepsis. Mitochondrial dysfunction plays an important role in septic cardiomyopathy. Studies have shown that cyclooxygenase-2 (COX-2) had a protective effect on the heart, and prostaglandin E2 (PGE2), the downstream product of COX-2, was increasingly recognized to have a protective effect on mitochondrial function. OBJECTIVE: This study aims to demonstrate that COX-2/PGE2 can protect against septic cardiomyopathy by regulating mitochondrial function. METHODS: Cecal ligation and puncture (CLP) was used to establish a mouse model of sepsis and RAW264.7 macrophages and H9C2 cells were used to simulate sepsis in vitro. The NS-398 and celecoxib were used to inhibit the activity of COX-2. ZLN005 and SR18292 were used to activate or inhibit the PGC-1α activity. The mitochondrial biogenesis was examined through the Mitotracker Red probe, mtDNA copy number, and ATP content detection. RESULTS: The experimental data suggested that COX-2 inhibition attenuated PGC-1α expression thus decreasing mitochondrial biogenesis, whereas increased PGE2 could promote mitochondrial biogenesis by activating PGC-1α. The results also showed that the effect of COX-2/PGE2 on PGC-1α was mediated by the activation of cyclic adenosine monophosphate (cAMP) response element binding protein (CREB). Finally, the effect of COX-2/PGE2 on the heart was also verified in the septic mice. CONCLUSION: Collectively, these results suggested that COX-2/PGE2 pathway played a cardioprotective role in septic cardiomyopathy through improving mitochondrial biogenesis, which has changed the previous understanding that COX-2/PGE2 only acted as an inflammatory factor.

Cyy-272, an indazole derivative, effectively mitigates obese cardiomyopathy as a JNK inhibitor.

Obesity has shown a global epidemic trend. The high-lipid state caused by obesity can maintain the heart in a prolonged low-grade inflammatory state and cause ventricular remodeling, leading to a series of pathologies, such as hypertrophy, fibrosis, and apoptosis, which eventually develop into obese cardiomyopathy. Therefore, prolonged low-grade inflammation plays a crucial role in the progression of obese cardiomyopathy, making inflammation regulation an essential strategy for treating this disease. Cyy-272, an indazole derivative, is an anti-inflammatory compound independently synthesized by our laboratory. Our previous studies revealed that Cyy-272 can exert anti-inflammatory effects by inhibiting the phosphorylation and activation of C-Jun N-terminal kinase (JNK), thereby alleviating lipopolysaccharide (LPS)-induced acute lung injury (ALI). The current study aimed to evaluate the potential of Cyy-272 to mitigate the occurrence and progression of obese cardiomyopathy through the inhibition of the JNK signaling pathway. Our results indicate that the compound Cyy-272 has encouraging therapeutic effects on obesity-induced cardiac injury. It significantly inhibits inflammation in cardiomyocytes and heart tissues induced by high lipid concentrations, further alleviating the resulting hypertrophy, fibrosis, and apoptosis. Mechanistically, the protective effect of Cyy-272 on obese cardiomyopathy can be attributed to its direct inhibition of JNK protein phosphorylation. In conclusion, we identified a novel compound, Cyy-272, capable of alleviating obese cardiomyopathy and confirmed that its effect is achieved through direct inhibition of JNK.

Monitoring the Efficacy of Tafamidis in ATTR Cardiac Amyloidosis by MRI-ECV: A Systematic Review and Meta-Analysis.

BACKGROUND: The usefulness of monitoring treatment effect of tafamidis using magnetic resonance imaging (MRI) extracellular volume fraction (ECV) has been reported. OBJECTIVE: we conducted a meta-analysis to evaluate the usefulness of this method. METHODS: Data from 246 ATTR-CMs from six studies were extracted and included in the analysis. An inverse variance meta-analysis using a random effects model was performed to evaluate the change in MRI-ECV before and after tafamidis treatment. The analysis was also performed by classifying the patients into ATTR-CM types (wild-type or hereditary). RESULTS: ECV change before and after tafamidis treatment was 0.33% (95% CI: -1.83-2.49, I2 = 0%, p = 0.76 for heterogeneity) in the treatment group and 4.23% (95% CI: 0.44-8.02, I2 = 0%, p = 0.18 for heterogeneity) in the non-treatment group. The change in ECV before and after treatment was not significant in the treated group (p = 0.76), but there was a significant increase in the non-treated group (p = 0.03). There was no difference in the change in ECV between wild-type (95% CI: -2.65-3.40) and hereditary-type (95% CI: -9.28-4.28) (p = 0.45). CONCLUSIONS: The results of this meta-analysis suggest that MRI-ECV measurement is a useful imaging method for noninvasively evaluating the efficacy of tafamidis treatment for ATTR-CM.

Response to therapy with tafamidis 61 mg in patients with cardiac transthyretin amyloidosis: real-world experience since approval.

AIMS: Transthyretin amyloid cardiomyopathy (ATTR-CM) is a progressive disease that causes heart failure due to amyloid fibril deposition. Tafamidis was approved as the first causal treatment in 2020. We here report on real-world data in patients treated with tafamidis for at least 12 months according to the recently defined European Society for Cardiology (ESC) consensus criteria for disease progression. METHODS AND RESULTS: Three hundred and eight wildtype and 31 hereditary ATTR-CM patients were prospectively enrolled after first diagnosis of ATTR-CM and initiation of tafamidis 61 mg once daily treatment. After 12 months, significant deterioration in Karnofsky Index, estimated glomerular filtration rate (eGFR), N-terminal brain natriuretic peptide (NT-proBNP), septum thickness and left ventricular ejection fraction (LVEF) could be observed, significant disease progression was only detected in 25 patients (9%) using ESC consensus criteria. Mean survival time was 37 months with no differences between responders and non-responders. NT-proBNP was the only independent predictor for poor therapy response (p = .008). CONCLUSIONS: The majority of patients showed no significant disease progression according to the ESC consensus criteria after 12 months of therapy with tafamidis. However, at 12 months, treatment response based on the ESC consensus criteria was not associated with improved survival. Moreover, higher levels of NT-proBNP at diagnosis of ATTR-CM appears to predict poorer treatment response, confirming that timely initiation of therapy is advantageous.

Sacubitril/valsartan alleviates sepsis-induced myocardial injury in rats via dual angiotensin receptor-neprilysin inhibition and modulation of inflammasome/caspase 1/IL1ß pathway.

Sepsis is a life-threatening situation that ultimately affects cardiac function, leading to cardiomyopathy and myocardial injury as a result of uncontrolled response to infection.Till now, there is limited effective treatment to rescue those cases. Thus, novel therapeutic strategies should be identified to achieve better outcomes for septic patients. For the first time, we aimed to evaluate the effect of sacubitril/valsartan (Sac/Val) on sepsis-induced cardiac injury. Wistar male adult albino rats were randomly divided into four groups; Group I received the vehicle; Group II was given the vehicle plus 1 ml saline containing viable Escherichia coli (E. coli) (2.1 × 109 cfu) by intraperitoneal (i.p.) injection on the 1st and 2nd days; Group III received i.p. injection as group II plus oral administration of Sac/Val (30 mg/kg/day) and Nitro- ω-L-arginine (L-NNA) (25 mg/kg/day) for 7 days. Group IV was administered i.p. injection as group II plus oral administration of Sac/Val (30 mg/kg/day) for 7 days. Our data (n = 10) revealed successful induction of sepsis as it showed a significant increase in the measured cardiac enzymes, malondialdehyde (MDA), angiotensin II (Ang II), neprilysin, inflammasome, caspase 1, interleukin (IL)1ß, and caspase 3 with cardiac histopathological changes, but there was a significant decrease in the antioxidants and blood pressure (BP). Co-administration of Sac/Val could obviously improve these changes. Interestingly, L-NNA given group showed a decrease in the cardioprotective effect of Sac/Val. Sac/Val could ameliorate sepsis induced cardiac damage via inhibition of Ang II and neprilysin with anti-inflammatory, anti-oxidant and anti-apoptotic properties.

Tamoxifen may contribute to preserve cardiac function in Duchenne muscular dystrophy.

Duchenne muscular dystrophy is life-limiting. Cardiomyopathy, which mostly ensues in the second decade of life, is the main cause of death. Treatment options are still limited. The TAMDMD (NCT03354039) trial assessed motor function, muscle strength and structure, laboratory biomarkers, and safety in 79 ambulant boys with genetically confirmed Duchenne muscular dystrophy, 6.5-12 years of age, receiving either daily tamoxifen 20 mg or placebo for 48 weeks. In this post-hoc analysis, available echocardiographic data of ambulant patients recruited at one study centre were retrieved and compared before and after treatment. Data from 14 patients, median 11 (interquartile range, IQR, 11-12) years of age was available. Baseline demographic characteristics were similar in participants assigned to placebo (n = 7) or tamoxifen (n = 7). Left ventricular end-diastolic diameter in the placebo group (median and IQR) was 39 (38-41) mm at baseline and 43 (38-44) mm at study end, while it was 44 (41-46) mm at baseline and 41 (37-46) mm after treatment in the tamoxifen group. Left ventricular fractional shortening in the placebo group was 35% (32-38%) before and 33% (32-36%) after treatment, while in the tamoxifen group it was 34% (33-34%) at baseline and 35% (33-35%) at study end. No safety signals were detected. CONCLUSION: This hypothesis-generating post-hoc analysis suggests that tamoxifen over 48 weeks is well tolerated and may help preserving cardiac structure and function in Duchenne muscular dystrophy. Further studies are justified. CLINICALTRIALS: gov Identifier: EudraCT 2017-004554-42, NCT03354039 What is known: • Duchenne muscular dystrophy (DMD) is life-limiting. Cardiomyopathy ensues in the second decade of life and is the main cause of death. Treatment options are still limited. • Tamoxifen reduced cardiac fibrosis in mice and improved cardiomyocyte function in human-induced pluripotent stem cell-derived cardiomyocytes. WHAT IS NEW: • In this post-hoc analysis of the TAMDMD trial among 14 boys, median 11 years of age, treated with either tamoxifen or placebo for 48 weeks, treatment was well-tolerated. • A visual trend of improved left-ventricular dimensions and better systolic function preservation generates the hypothesis of a potential beneficial effect of tamoxifen in DMD cardiomyopathy.

Vaccarin alleviates septic cardiomyopathy by potentiating NLRP3 palmitoylation and inactivation.

BACKGROUND: Sepsis often leads to significant morbidity and mortality due to severe myocardial injury. As is known, the activation of NOD-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome crucially contributes to septic cardiomyopathy (SCM) by facilitating the secretion of interleukin (IL)-1ß and IL-18. The removal of palmitoyl groups from NLRP3 is a crucial step in the activation of the NLRP3 inflammasome. Thus, the potential inhibitors that regulate the palmitoylation and inactivation of NLRP3 may significantly diminish sepsis-induced cardiac dysfunction. PURPOSE: The present study sought to explore the effects of the prospective flavonoid compounds targeting NLRP3 on SCM and to elucidate the associated underlying mechanisms. STUDY DESIGN: The palmitoylation and activation of NLRP3 were detected in H9c2 cells and C57BL/6 J mice. METHODS/RESULTS: Echocardiography, histological staining, western blotting, co-immunoprecipitation, qPCR, ELISA and network pharmacology were used to assess the impact of vaccarin (VAC) on SCM in mice subjected to lipopolysaccharide (LPS) injection. From the collection of 74 compounds, we identified that VAC had the strongest capability to suppress NLRP3 luciferase report gene activity in cardiomyocytes, and the anti-inflammatory characteristics of VAC were further ascertained by the network pharmacology. Exposure of LPS triggered apoptosis, inflammation, oxidative stress, mitochondrial disorder in cardiomyocytes. The detrimental alterations were significantly reversed upon VAC treatment in both septic mice and H9c2 cells exposed to LPS. In vivo experiments demonstrated that VAC treatment alleviated septic myocardial injury, indicated by enhanced cardiac function parameters, preserved cardiac structure, and reduced inflammation/oxidative response. Mechanistically, VAC induced NLRP3 palmitoylation to inactivate NLRP3 inflammasome by acting on zDHHC12. In support, the NLRP3 agonist ATP and the acylation inhibitor 2-bromopalmitate (2-BP) prevented the effects of VAC. CONCLUSION: Our findings suggest that VAC holds promise in protecting against SCM by mitigating cardiac oxidative stress and inflammation via priming NLRP3 palmitoylation and inactivation. These results lay the solid basis for further assessment of the therapeutic potential of VAC against SCM.

The clinical effectiveness of sivelestat in treating sepsis patients with both acute respiratory distress syndrome and septic cardiomyopathy.

BACKGROUND: We aimed to assess the efficacy of the neutrophil elastase inhibitor, sivelestat, in the treatment of sepsis-induced acute respiratory distress syndrome (ARDS) and septic cardiomyopathy (SCM). METHODS: Between January 2019 and December 2021, we conducted a randomized trial on patients who had been diagnosed with sepsis-induced acute respiratory distress syndrome (ARDS) and septic cardiomyopathy (SCM) at Wuhan Union Hospital. The patients were divided into two groups by random envelop method, the Sivelestat group and the Control group. We measured the serum concentrations of Interleukin (IL)-6, IL-8, Tumor necrosis factor-α (TNF-α), and High-mobility group box 1 (HMGB1) at five time points, which were the baseline, 12 h, 24 h, 48 h, and 72 h after admission to the ICU. We evaluated the cardiac function by sonography and the heart rate variability (HRV) with 24-hour Holter recording between the time of admission to the intensive care unit (ICU) and 72 h after Sivelestat treatment. RESULTS: From January 2019 to December 2021, a total of 70 patients were included in this study. The levels of IL-6, IL-8, and TNF-α were significantly lower in the Sivelestat group at different time points (12 h, 24 h, 48 h, and 72 h). HMGB1 levels were significantly lower at 72 h after Sivelestat treatment (19.46 ± 2.63pg/mL vs. 21.20 ± 2.03pg/mL, P = 0.003). The stroke volume (SV), tricuspid annular plane systolic excursion (TAPSE), early to late diastolic transmitral flow velocity (E/A), early (e') and late (a') diastoles were significantly low in the Control group compared with the Sivelestat group. Tei index was high in the Control group compared with the Sivelestat group (0.60 ± 0.08 vs. 0.56 ± 0.07, P = 0.029). The result of HRV showed significant differences in standard deviation of normal-to-normal intervals (SDNN), low frequency (LF), and LF/HF (high frequency) between the two groups. CONCLUSIONS: Sivelestat can significantly reduce the levels of serum inflammatory factors, improve cardiac function, and reduce heart rate variability in patients with Sepsis-induced ARDS and SCM.

SGLT2 Inhibitor Therapy in Patients With Transthyretin Amyloid Cardiomyopathy.

BACKGROUND: Transthyretin cardiomyopathy (ATTR-CM) was an exclusion criterion in randomized clinical trials of sodium-glucose cotransporter 2 inhibitors (SGLT2i). OBJECTIVES: This study sought to assess the effectiveness and tolerability of SGLT2i in patients with ATTR-CM. METHODS: Data of 2,356 consecutive ATTR-CM patients (2014-2022) were analyzed: 260 (11%) received SGLT2i. After comparing the groups according to the treatment, 14 variables were significantly different-age and N-terminal pro-B-type natriuretic peptide were included in the model. A propensity score reflecting the likelihood of being treated with SGLT2i for each patient was determined using 16 variables. RESULTS: The study comprised 220 patients treated with SGLT2i (age 77 ± 2 years; 82.3% wild-type ATTR-CM; left ventricular ejection fraction 45.8% ± 11%) and 220 propensity-matched control individuals. Adequacy of matching was verified (standardized differences: <0.10 between groups). Discontinuation rate for SGLT2i was 4.5%; at 12 months, SGLT2i treatment was associated with less worsening of NYHA functional class, N-terminal pro-B-type natriuretic peptide, estimated glomerular filtration rate, and fewer new initiations of loop diuretic agent therapy. Over 28 months (Q1-Q3: 18-45 months), SGLT2i therapy was associated with lower all-cause mortality (HR: 0.57; 95% CI: 0.37-0.89; P = 0.010), cardiovascular mortality (HR: 0.41; 95% CI: 0.24-0.71; P < 0.001), heart failure (HF) hospitalization (HR: 0.57; 95% CI: 0.36-0.91; P = 0.014), and the composite outcome of cardiovascular mortality and HF hospitalization (HR: 0.57; 95% CI: 0.38-0.84; P = 0.003). CONCLUSIONS: SGLT2i treatment in ATTR-CM patients was well tolerated and associated with favorable effects on HF symptoms, renal function, and diuretic agent requirement over time. SGLT2i treatment was associated with reduced risk of HF hospitalization and cardiovascular and all-cause mortality, regardless of the ejection fraction, despite the effect size being likely overestimated. In the absence of randomized trials, these data may inform clinicians regarding the use of SGLT2i in patients with ATTR-CM.

Specific Therapy in Transthyretin Amyloid Cardiomyopathy: Future Perspectives Beyond Tafamidis.

Transthyretin amyloid cardiomyopathy (ATTR-CM) is a relatively prevalent cause of morbidity and mortality. Over the recent years, development of disease-modifying treatments has enabled stabilization of the circulating transthyretin tetramer and suppression of its hepatic production, resulting in a remarkable improvement in survival of patients with ATTR-CM. Second-generation drugs for silencing are currently under investigation in randomized clinical trials. In vivo gene editing of transthyretin has been achieving unanticipated suppression of hepatic production in ATTR-CM. Trials of antibodies inducing the active removal of transthyretin amyloid deposits in the heart are ongoing, and evidence has gathered for exceptional spontaneous regression of ATTR-CM.

Tafamidis in the Treatment of ATTR-related Cardiomyopathy: Indications and Grey Zones.

Transthyretin amyloid cardiomyopathy (ATTR-CM) is caused by the myocardial extracellular deposition of amyloid fibrils formed from the dissociation of TTR tetramer into monomers. The rate-limiting step in TTR amyloidogenesis is the dissociation of the TTR tetramer into monomers: Tafamidis is an effective TTR-stabilizer in its native homotetrameric structure. Tafamidis is a safe and effective drug in reducing symptoms, hospitalization and mortality in accurately selected patients affected by hereditary and wild-type transthyretin amyloid cardiomyopathy.

Cardiac Biomarker Change at 1 Year After Tafamidis Treatment and Clinical Outcomes in Patients With Transthyretin Amyloid Cardiomyopathy.

BACKGROUND: Although tafamidis treatment improves prognosis in patients with wild-type transthyretin amyloid cardiomyopathy, an optimal surrogate marker monitoring its therapeutic effect remains unclear. This study investigated the association between changes in cardiac biomarkers, high-sensitivity cardiac troponin T (hs-cTnT) and B-type natriuretic peptide (BNP) during the first year after tafamidis treatment and clinical outcomes. METHODS AND RESULTS: In 101 patients with wild-type transthyretin amyloid cardiomyopathy receiving tafamidis at our institution, change in cardiac biomarkers from baseline to 1 year after tafamidis administration and its association with composite outcomes (composite of all-cause death and hospitalization attributable to heart failure) was assessed. During the follow-up period (median, 17 months), 16 (16%) patients experienced composite outcomes. The hs-cTnT level significantly decreased at 1 year after tafamidis treatment, unlike the BNP level. The frequencies of increased hs-cTnT and BNP levels were significantly higher in those with composite outcomes than in those without (44% versus 15%; P=0.01). Kaplan-Meier survival analysis showed that patients in whom both hs-cTnT and BNP levels increased at 1 year after tafamidis had a higher probability of composite outcomes compared with those with decreased hs-cTnT and BNP levels (log-rank P<0.01). Cox regression analysis identified increased hs-cTnT and BNP levels at 1 year after tafamidis administration as an independent predictor of higher cumulative risk of composite outcomes. CONCLUSIONS: Deterioration in cardiac biomarkers during the first year after tafamidis treatment predicted a worse prognosis, suggesting the utility of serial assessment of cardiac biomarkers for monitoring the therapeutic response to tafamidis in patients with wild-type transthyretin amyloid cardiomyopathy.

Zhen-wu-tang protects against myocardial fibrosis by inhibiting M1 macrophage polarization via the TLR4/NF-κB pathway.

BACKGROUND: Myocardial fibrosis is a risk factor that contributes to the increase in the incidence of cardiovascular disease and death, posing a significant threat to human health. Zhen-wu-tang (ZWT) is a classical Chinese medicinal recipe that has been extensively used to manage cardiovascular disorders throughout history. However, the fundamental processes involved in its effects were not clear. OBJECTIVE: This study examined the therapeutic effects of ZWT on myocardial fibrosis induced by isoproterenol (ISO) in mice, the effect of regulation and underlying mechanism on the polarization of M1 macrophage. METHODS: In vivo, a myocardial fibrosis mouse model was induced via intraperitoneal infusion of isoproterenol (ISO). ZWT or captopril (CAP) was administered intragastrically for 30 days. Cardiac function was evaluated by electrocardiogram (ECG) and echocardiography. By analysing myocardial fibrosis pathomorphologically and identifying fibrosis-related indicators, the protective effect of the ZWT on the heart was evaluated. A model of macrophage polarization was established in vitro by activating RAW264.7 cells with lipopolysaccharide (LPS). The regulatory effects of ZWT on macrophage polarization and the signalling pathways involved were examined by immunofluorescence staining, Western blotting (WB), quantitative real-time PCR (qRT-PCR) and siRNA transfection. RESULTS: ZWT improved cardiac function; reduced fibrotic deposition in cardiac tissues; decreased α-SMA, collagen I, and collagen III levels; and inhibited myocardial fibrosis in mice with ISO-induced myocardial fibrosis. Furthermore, the results showed that ZWT could suppress M1 macrophage polarization by downregulating the expression of CD86 and iNOS in vitro and in vivo. Finally, the results confirmed that ZWT could significantly reduce TLR4/NF-κB signalling pathway activation. CONCLUSION: ZWT showed therapeutic effects on ISO-induced myocardial fibrosis mice, and reduced M1 macrophages polarization through inhibiting TLR4/NF-κB pathway, suggesting that ZWT is a promising drug for myocardial fibrosis treatment.

Dapagliflozin attenuates LPS-induced myocardial injury by reducing ferroptosis.

Septic cardiomyopathy is a severe cardiovascular disease with a poor prognosis. Previous studies have reported the involvement of ferroptosis in the pathogenesis of septic cardiomyopathy. SGLT2 inhibitors such as dapagliflozin have been demonstrated to improve ischemia-reperfusion injury by alleviating ferroptosis in cardiomyocyte. However, the role of dapagliflozin in sepsis remains unclear. Therefore, our study aims to investigate the therapeutic effects of dapagliflozin on LPS-induced septic cardiomyopathy. Our results indicate that dapagliflozin improved cardiac function in septic cardiomyopathy experimental mice. Mechanistically, dapagliflozin works by inhibiting the translation of key proteins involved in ferroptosis, such as GPX4, FTH1, and SLC7A11. It also reduces the transcription of lipid peroxidation-related mRNAs, including PTGS2 and ACSL4, as well as iron metabolism genes TFRC and HMOX1.

Elucidating the mechanism of action of Radix Angelica sinensis (Oliv.) Diels and Radix Astragalus mongholicus Bunge ultrafiltration extract on radiation-induced myocardial fibrosis based on network pharmacology and experimental research.

Myocardial fibrosis can induce cardiac dysfunction and remodeling. Great attention has been paid to traditional chinese medicine (TCM) 's effectiveness in treating MF. Radix Angelica sinensis (Oliv.) Diels and Radix Astragalus mongholicus Bunge ultrafiltration extract (RAS-RA), which is a key TCM compound preparation, have high efficacy in regulating inflammation. However, studies on its therapeutic effect on radiation-induced myocardial fibrosis (RIMF) are rare. In this study, RAS-RA had therapeutic efficacy in RIMF and elucidated its mechanism of action. First, we formulated the prediction network that described the relation of RAS-RA with RIMF according to data obtained in different databases. Then, we conducted functional enrichment to investigate the functions and pathways associated with potential RIMF targets for RAS-RA. In vivo experiments were also performed to verify these functions and pathways. Second, small animal ultrasound examinations, H&E staining, Masson staining, transmission electron microscopy, Enzyme-linked immunosorbent assay (ELISA), Western-blotting, Immunohistochemical method and biochemical assays were conducted to investigate the possible key anti-RIMF pathway in RAS-RA. In total, 440 targets were detected in those 21 effective components of RAS-RA; meanwhile, 1,646 RIMF-related disease targets were also discovered. After that, PPI network analysis was conducted to identify 20 key targets based on 215 overlap gene targets. As indicated by the gene ontology (GO) and kyoto encyclopedia of genes and genomes (KEGG) analysis results, inflammation and PI3K/AKT/mTOR pathways might have important effects on the therapeutic effects on RIMF. Molecular docking analysis revealed high binding of effective components to targets (affinity < -6 kcal/mol). Based on experimental verification results, RAS-RA greatly mitigated myocardial fibrosis while recovering the cardiac activity of rats caused by X-rays. According to relevant protein expression profiles, the PI3K/AKT/mTOR pathway was important for anti-fibrosis effect of RAS-RA. Experimental studies showed that RAS-RA improved cardiac function, decreased pathological damage and collagen fiber deposition in cardiac tissues, and improved the mitochondrial structure of the heart of rats. RAS-RA also downregulated TNF-α, IL-6, and IL-1ß levels. Additionally, RAS-RA improved the liver and kidney functions and pathological injury of rat kidney and liver tissues, enhanced liver and kidney functions, and protected the liver and kidneys. RAS-RA also increased PI3K, AKT and mTOR protein levels within cardiac tissues and downregulated α-SMA, Collagen I, and Collagen III. The findings of this study suggested that RAS-RA decreased RIMF by suppressing collagen deposition and inflammatory response by inhibiting the PI3K/AKT/mTOR pathway. Thus, RAS-RA was the potential therapeutic agent used to alleviate RIMF.

Effect of tafamidis on left atrial function of patients with transthyretin amyloid cardiomyopathy.

Transthyretin amyloid cardiomyopathy (ATTR-CM) is characterized by the functional and structural effects of amyloid infiltration, predominantly within the ventricles, causing biventricular wall thickening. Amyloid infiltration can be observed in the left atrium in ATTR-CM patients, but the association of left atrial (LA) myocardial function with cardiovascular events and of changes in LA myocardial function with tafamidis administration have not yet been clarified. Our aim was, therefore, to use speckle-tracking strain for investigating LA myocardial function in patients with ATTR-CM treated with tafamidis. We studied 55 patients with biopsy-proven ATTR-CM who had been treated with tafamidis (age: 76 ± 2 years, male: 93%). For speckle-tracking analysis of LA myocardial function, the systolic LA strain (LA reservoir function) was defined for this study as LA myocardial function from the apical 4-chamber view. The primary endpoint was defined as a composite comprising cardiovascular death and/or heart failure hospitalization after tafamidis administration over a median follow-up period of 28 ± 4 months. Patients with baseline LA strain < 8.6% (median value) experienced significantly more cardiovascular events than those without (log-rank P = 0.002). Moreover, LA strain in 26 patients worsened after tafamidis administration, and multivariate logistic regression analysis showed age, global longitudinal strain and relative apical longitudinal strain index were identified as independent determinants of deterioration of LA strain after tafamidis administration. In conclusion, baseline LA reservoir function is closely associated with cardiovascular events after tafamidis administration, and could be an additional parameter for the management of patients with ATTR-CM.