Ultrasensitive Proteomics of Trace Cardiac Tissues with Anchor-Nanoparticles.

Pathological cardiac hypertrophy is a complex process that often leads to heart failure. Label-free proteomics has emerged as an important platform to reveal protein variations and to elucidate the mechanisms of cardiac hypertrophy. Endomyocardial biopsy is a minimally invasive technique for sampling cardiac tissue, but it yields only limited amounts of an ethically permissible specimen. After regular pathological examination, the remaining trace samples pose significant challenges for effective protein extraction and mass spectrometry analysis. Herein, we developed trace cardiac tissue proteomics based on the anchor-nanoparticles (TCPA) method. We identified an average of 6666 protein groups using ∼50 µg of myocardial interventricular septum samples by TCPA. We then applied TCPA to acquire proteomics from patients' cardiac samples both diagnosed as hypertrophic hearts and myocarditis controls and identified significant alterations in pathways such as regulation of actin cytoskeleton, oxidative phosphorylation, and cGMP-PKG signaling pathway. Moreover, we found multiple lipid metabolic pathways to be dysregulated in transthyretin cardiac amyloidosis compared to other types of cardiac hypertrophy. TCPA offers a new technique for studying pathological cardiac hypertrophy and can serve as a platform toolbox for proteomic research in other cardiac diseases.

Enhanced Surgical Outcomes of Popliteal Cyst Excision: A Retrospective Study Comparing Arthroscopic Debridement with and without Methylene Blue Injection.

BACKGROUND This retrospective study of 42 patients with popliteal cysts (or Baker cysts) aimed to compare the effects on duration and outcomes of arthroscopic surgical debridement with and without the use of cyst injection with methylene blue (MB). MATERIAL AND METHODS Medical records of patients who underwent conventional arthroscopic surgery (n=20) or arthroscopic surgery after MB injection (n=22) for popliteal cysts between 2018 and 2021 were reviewed. The MB group underwent arthroscopic popliteal cystectomy with MB as the marker, and the control group underwent conventional arthroscopic popliteal cystectomy. Surgical time of cyst resection, postoperative bruising extent, complication rate, and cyst recurrence rate of the 2 groups were compared. RESULTS The MB group had a faster surgical cyst removal time (16.5±1.5 min) than the control group (24.5±1.6 min; P<0.05). The MB group had less postoperative bruising (1 case, 4.5%) than the control group (5 cases, 25%; P<0.05). The surgical results were similar in both groups, with a Lysholm score of 87.23±1.80 in the MB group and 87.23±1.62 (P>0.05) in the control group. CONCLUSIONS This study showed that preoperative injection of MB for popliteal cysts before arthroscopic debridement improved cyst localization and ease and accuracy of surgery and reduced operative time, adjacent tissue damage, postoperative complications, and recurrence rate.

The Proportion of Circulating CD45RO+CD8+ T Cells is Associated with the Coronary Slow Flow.

Background: Circulating memory CD8+ T cells have been shown to be a crucial mediator of chronic inflammation. This study investigated whether the baseline proportion of circulating CD45RO+CD8+ T cells was associated with the coronary slow flow (CSF) phenomenon. Methods: A total of 160 consecutive patients [mean (standard deviation (SD)) age, 67.86 (9.55) years; 51.25% male] who were admitted to our hospital between August 2020 and October 2020 for chest pain and underwent coronary angiography with the absence of coronary stenosis were enrolled in this cross-sectional analysis. The patients' admission CD45RO+ CD8+ T cell plasma levels were measured using flow cytometry. Angiographic CSF was defined as thrombolysis in myocardial infarction (TIMI) flow of ≤ 2 without coronary stenosis, and non-CSF was defined as coronary arteries (< 50% stenosis) with TIMI 3 flow. Results: The incidence of angiographic CSF was 22.5%. Patients with angiographic CSF had higher levels of CD45RO+CD8+ T cells than those without CSF [56.18 (13.93) vs. 45.26 (16.45); p < 0.001]. After multivariable adjustment, the risk of incident CSF was 2.41 [95% confidence interval (CI) 1.46-3.97] per SD change in CD45RO+ CD8+ T cells. Further, coronary microvascular resistance was significantly higher in patients with CSF than in those without CSF. A positive linear relationship between CD45RO+CD8+ T cells and coronary microvascular resistance was observed. Conclusions: The proportion of circulating CD45RO+CD8+ T cells is an independent indicator of CSF. This observation may provide insights into the pathophysiological mechanism of CSF.

Role of TLR4/NADPH oxidase 4 pathway in promoting cell death through autophagy and ferroptosis during heart failure.

Loss of myocytes caused by cell death plays a key role during heart failure (HF). Activated autophagy and increased ferroptosis have been observed in HF and proved to promote its progression. However, the underlying mechanisms remain unclear. Here, results from integrated bioinformatical analysis showed TLR4 and NADPH oxidase 4 (NOX4) were included in up-regulated differentially expressed genes (DEGs), and had an interaction between each other inferred by the DEGs-associated protein-protein interaction (PPI) network. To explore the role of TLR4-NOX4 in autophagy and ferroptosis, knock-down of TLR4 and NOX4 through lentiviral delivery of siRNA to the myocardium were applied respectively in HF rats induced by aortic banding, and the indicators of autophagy and ferroptosis were detected. Results revealed that either TLR4 or NOX4 knock-down significantly improved left ventricular remodeling and reduced myocytes death. Simultaneously, activated autophagy and ferroptosis in rats with HF were remarkably retarded by either TLR4 and NOX4 knock-down, suggesting TLR4-NOX4 as a potential therapeutic target for HF through inhibiting autophagy- and ferroptosis-mediated cell death.

Puerarin protects against heart failure induced by pressure overload through mitigation of ferroptosis.

Heart failure (HF) is the end stage of cardiovascular disease and is characterized by the loss of myocytes caused by cell death. Puerarin has been found to improve HF clinically, and animal study findings have confirmed its anti-cell-death properties. However, the underlying mechanisms remain unclear, especially with respect to the impact on ferroptosis, a newly defined mechanism of iron-dependent non-apoptotic cell death in HF. Here, ferroptosis-like cell death was observed in erastin- or isoprenaline (ISO)-treated H9c2 myocytes in vitro and in rats with aortic banding inducing HF, characterized by reduced cell viability with increased lipid peroxidation and labile iron pool. Interestingly, the increased iron overload and lipid peroxidation observed in either rats with HF or H9c2 cells incubated with ISO were significantly blocked by puerarin administration. These results provide compelling evidence that puerarin plays a role in inhibiting myocyte loss during HF, partly through ferroptosis mitigation, suggesting a new mechanism of puerarin as a potential therapy for HF.

Elevated soluble ST2 and depression increased the risk of all-cause mortality and hospitalization in patients with heart failure.

This study aimed to assess the predictive effect of soluble ST2 (sST2) and depressive symptoms in patients with heart failure (HF) and to determine whether the prognosis of HF patients with preserved ejection fraction (HFpEF) differs from those with reduced ejection fraction (HFrEF). A cohort of 233 HF patients was followed for 1 year. Depressive symptoms were evaluated by the Hospital Anxiety and Depression Scale. The primary endpoint was all-cause mortality and HF-related hospitalization. For the analysis of survival, the left ventricular ejection fraction (LVEF) cut-offs for defining HFpEF were set at 50%, 45%, and 40%, respectively. With increasing LVEF, levels of sST2 were gradually decreased (45.2 ng/mL, 35.8 ng/mL, and 32.1 ng/mL in patients with LVEF ≤ 40%, 41% to 49%, and ≥ 50%, respectively, P for trend < 0.001), as well as the prevalence of depressive symptoms (35.4%, 33.3%, and 20.4%, respectively, P for trend = 0.022). After 1-year follow-up, 128 patients (54.9%) achieved the primary endpoint and 47 patients (20.2%) died. Depressive symptoms were independent risk factors of all-cause mortality and HF-related hospitalization. The combined presence of elevated sST2 (> 36.0 ng/mL) and depressive symptoms was associated with a 4.9-fold increased risk of the primary endpoint. Regardless of LVEF cut-offs, the associated risk of adverse outcomes in HFpEF was as high as in HFrEF after adjustment for significant risk factors including sST2 and N-terminal pro-brain natriuretic peptide. In conclusion, depressive symptoms provided additional prognostic information to that of sST2 in HF patients. The prognosis of HFpEF patients was similar to that of HFrEF patients.

FGF6 enhances muscle regeneration after nerve injury by relying on ERK1/2 mechanism.

BACKGROUND: Severe peripheral nerve injury leads to skeletal muscle atrophy and impaired limb function that is not sufficiently improved by existing treatments. Fibroblast growth factor 6 (FGF6) is involved in tissue regeneration and is dysregulated in denervated rat muscles. However, the way that FGF6 affects skeletal muscle repair after peripheral nerve injury has not been fully elucidated. METHODS: In this study, we investigated the role of FGF6 in the regeneration of denervated muscles using myoblast cells and an in vivo model of peripheral nerve injury. RESULTS: FGF6 promoted the viability and migration of C2C12 and primary myoblasts in a dose-dependent manner through FGFR1-mediated upregulation of cyclin D1. Low concentrations of FGF6 promoted myoblast differentiation through FGFR4-mediated activation of ERK1/2, which upregulated expression of MyHC, MyoD, and myogenin. FGFR-1, FGFR4, MyoD, and myogenin were not upregulated when FGF6 expression was inhibited in myoblasts by shRNA-mediated knockdown. Injection of FGF6 into denervated rat muscles enhanced the MyHC-IIb muscle fiber phenotype and prevented muscular atrophy. CONCLUSION: These findings indicate that FGF6 reduces skeletal muscle atrophy by relying on the ERK1/2 mechanism and enhances the conversion of slow muscle to fast muscle fibers, thereby promoting functional recovery of regenerated skeletal muscle after innervation.

Surgical Treatment of Intraneural Ganglion Cysts of the Ulnar Nerve at the Elbow: Long-Term Follow-up of 9 Cases.

BACKGROUND: Intraneural ganglion (IG) cysts have been considered curiosities and their pathogenesis remains controversial. OBJECTIVE: To clarify ulnar nerve at the elbow (UNE) pathogenesis and long-term surgical outcomes by presenting 9 rare cases of IG of the UNE. METHODS: Surgical treatment of IG was performed. Clinical symptoms, physical examinations, and electromyogram were evaluated pre- and postoperatively. At least 4 yr of follow-up was performed. RESULTS: The Tinel's sign became negative and local elbow pain disappeared in all 9 patients after surgery, and the average visual analog scale/score dropped from 4.9 (3-8) to 0 (0-0) after 6.2 d (2-10) on average. Two patients retained positive Froment test, "claw hand" and paresthesias with the 2-point discrimination much different from the contralateral little finger. Postoperative the UK Medical Research Council muscle strength score (MRC) grades of the flexor carpi ulnaris and the flexor digitorum profundus muscle of the fourth and fifth digits recovered to M4-M5 from M0-M2 in all 9 patients. The postoperative MRC grades of the third to fourth lumbrical muscles, the interossei, and the hypothenar recovered to M3-M5 from M0-M2 in 7 patients. Cystic articular branch (CAB) was found in all 9 patients intraoperatively. No symptomatic recurrence of IG was seen. The mean motor nerve conduction velocity of ulnar nerve across the elbow recovered from 5.3 to 41.2 m/s. CONCLUSION: A unifying articular theory is responsible for the pathogenesis of IG of UNE and disconnection of the CAB would prevent recurrence. The long-term outcome is good after surgical treatment of IG of UNE.

Relationship between changes in muscle fibers and CMAP in skeletal muscle with different stages of aging.

AIM: This study aimed to investigate the relationship between the changes of muscle fibers and the changesof peripheral nerve functions (CMAP) with aging. METHODS: Lewis rats enrolled in this study. Muscle biopsy and CMAP of tibialis anterior (TA) were measured. RESULTS: CMAP amplitudes increased significantly in 6 months (P<0.05). CMAP latencies of peroneal nerves found to be significantly higher in older rats (P<0.05). In 6 months these two muscle fibers went through a significant decrease (P<0.05). Type IIb and type IIx muscle fibers increased significantly in 6 months when compared with those in 1 month (P<0.05). After 6 months, the percentages of type I and type IIa muscle fibers increased as the month increased (P<0.05). The percentages of type IIb muscle fibers and type IIx muscle fibers dropped significantly as the month increased (P<0.05). Type I and type IIa muscle fibers were negatively related to CMAP amplitudes (P<0.05). Type IIb muscle fibers were positively related to CMAP amplitudes (P<0.05). CONCLUSION AND DISCUSSION: There is a shift from the fast types (Type IIx and IIb) to slow types (Type I and IIa) in muscle fibers with agingwhich is consistent with changes in CMAP amplitude of peripheral nerves.

Relaxin-2 improves diastolic function of pressure-overloaded rats via phospholamban by activating Akt.

BACKGROUND: Relaxin is a peptide hormone which has been demonstrated to be safe and has a therapeutic effect on acute heart failure in clinic trials. However, its effect on diastolic function is still unknown. The aims of the study were to determine whether relaxin could improve the diastolic function in pressure-overloaded rat model and to analyze potential mechanisms. METHODS AND RESULTS: In the present study, a pressure-overloaded rat model induced by transaortic constriction (TAC) was established. Four weeks after TAC, echocardiography was performed and then all the rat models were randomly divided into 3 groups: models without intramyocardial injection (TAC), with intramyocardial injection of empty adenoviral vector (TAC+GFP) and adenoviral vector overexpression relaxin-2 gene (TAC+RLN2). A sham group was also included. Twelve days after intramyocardial injection, echocardiography and hemodynamics were carried out to evaluate diastolic function in sham, TAC, TAC+GFP and TAC+RLN2 groups. Then hearts were harvested for subsequent examinations. The results indicated that relaxin-2 had ameliorated diastolic function in the pressure-overloaded rats. Compared with the TAC and TAC+GFP groups, the relaxin-2 gene transfer increased phosphorylation of Akt at both the Ser473 and Thr308 sites. Meanwhile, it increased the Ser16 and Thr17- phosphorylation levels of phospholamban (PLB). Furthermore, SERCA2 activity was enhanced in the TAC+RLN2 group more than in the TAC and TAC+GFP groups. CONCLUSIONS: These results demonstrated that relaxin-2 gene therapy improved diastolic function in pressure-overloaded rats. The potential mechanism may be that relaxin-2 gene transfer enhances SERCA2 activity in hearts by increasing phospholamban phosphorylation through nuclear-targeted Akt phosphorylation.

Left atrial enlargement in the early stage of hypertensive heart disease: a common but ignored condition.

How to identify the early signs of hypertensive heart disease is the key to block or reverse the process of heart failure. The aim of this study was to evaluate the predictive value of left atrial (LA) enlargement in the early stage of hypertensive heart disease and to explore the correlations between LA enlargement and heart failure with normal ejection fraction (HFnEF), as well as the metabolic syndrome (MetS). Baseline clinical characteristics, biochemical indices, electrocardiographic and echocardiographic data were collected from 341 consecutive patients with essential hypertension. Among those patients, LA enlargement was more frequently presented than LV enlargement (57.2% vs 17.9%). Compared with patients without HFnEF, the prevalence of LA enlargement was higher in patients with HFnEF (82.9% vs 49.0%, P<.0001). From grade 2 to grade 3 hypertension, LA size was significantly larger in patients with MetS (P<.01) than those without. Multivariate linear regression analyses showed that age, body mass index, waist circumference, triglyceride level, and left ventricular diameter were independent predictors of LA enlargement. The simple measurement for identification of LA enlargement potentially allows early recognition of those patients at risk for heart failure, particularly among patients with MetS.

Usefulness of the Echocardiographic Multi-Parameter Score (EMPS) in evaluating left ventricular global heart function.

In this study, we established a new index by combining several echocardiographic parameters to quantify heart failure. We selected 233 consecutive patients who underwent both echocardiographic and plasma B-type natriuretic peptide (BNP) tests within 24 hours after referral for suspected heart failure. The echocardiographic parameters included systolic function, diastolic function, left ventricular chamber remodeling, valvular lesions, systolic pulmonary arterial pressure, and regional wall-motion abnormality. Each factor was scored from 1 to 3 points according to its severity. The total point from these 6 factors is the echocardiographic multi-parameter score (EMPS).The EMPS for 37, 51, 77, and 38 patients from New York Heart Association (NYHA) functional classes I, II, III, and IV, respectively, were 1.24 ± 1.25, 2.98 ± 1.83, 5.96 ± 2.38, and 7.21 ± 1.99, which were significantly different from the mean score of our 30 normal patients (P <0.001). Sensitivity, specificity, and accuracy of an EMPS ≥2 for diagnosis of NYHA classes II to IV were 93%, 83%, and 89%, respectively. The area under the receiver operating characteristic curve was 0.94 (95% confidence interval, 0.92-0.98; P <0.001). There were significant correlations between logBNP and EMPS (r=0.81, P <0.001) or Tei index (r=0.48, P <0.001). In multilinear regression analysis, EMPS, early/late transmitral flow, and peak systolic velocity from tissue Doppler were entered into the model (P <0.001). The standardized regression coefficient (r=0.68) of EMPS was much higher than those of the other 2 factors, which suggests that EMPS is a powerful predictor of BNP levels.