A novel protein encoded by circLARP1B promotes the proliferation and migration of vascular smooth muscle cells by suppressing cAMP signaling.

BACKGROUND AND AIMS: Circular RNA (circRNA) is closely related to atherosclerosis (AS) incidence and progression, but its regulatory mechanism in AS needs further elucidation. AS development is significantly influenced by abnormal vascular smooth muscle cells (VSMCs) growth and migration. This study explored the potential protein role of circLARP1B in VSMC proliferation and migration. METHODS: We performed whole-transcriptome sequencing in human normal arterial intima and advanced atherosclerotic plaques to screen for differentially expressed circRNAs. The sequencing results were combined with database analysis to screen for circRNAs with coding ability. Real-time quantitative polymerase chain reaction was utilized to assess circLARP1B expression levels in atherosclerotic plaque tissues and cells. circLARP1B-243aa function and pathway in VSMCs growth and migration were studied by scratch, transwell, 5-ethynyl-2'-deoxyuridine, cell counting kit-8, and Western blot experiments. RESULTS: We found that circLARP1B was downregulated in atherosclerotic plaque tissue and promoted the proliferation and migration of VSMCs. circLARP1B encodes a novel protein with a length of 243 amino acids. Through functional experiments, we confirmed the role of circLARP1B-243aa in enhancing VSMCs migration and proliferation. Mechanistically, circLARP1B-243aa promotes VSMCs migration and growth by upregulating phosphodiesterase 4C to inhibit the cyclic adenosine monophosphate signaling pathway. CONCLUSIONS: Our results suggested that circLARP1B could promote VSMCs growth and migration through the encoded protein circLARP1B-243aa. Therefore, it could be a treatment target and biomarker for AS.

Serum Free Fatty Acid Concentration Predicts ARDS after Off-Pump CABG: A Prospective Observational Study.

BACKGROUND: Free fatty acids (FFAs) are established risk factors for various cardiovascular and metabolic disorders. Elevated FFAs can trigger inflammatory response, which may be associated with the occurrence of acute respiratory distress syndrome (ARDS) in cardiac surgery. In this prospective study, we aimed to investigate the association between circulating FFA and the incidence of ARDS, as well as the length of ICU stay, in patients undergoing off-pump coronary artery bypass grafting (CABG). METHODS: We conducted a single-center, prospective, observational study among patients undergoing off-pump CABG. The primary endpoint was the occurrence of ARDS within 6 days after off-pump CABG. Serum FFA were measured at baseline and 24 h post-procedure, and the difference (Δ-FFA) was calculated. RESULTS: A total of 180 patients were included in the primary analysis. The median FFA was 2.3 mmol/L (quartile 1 [Q1]-Q3, 1.4-3.2) at baseline and 1.5 mmol/L (Q1-Q3, 0.9-2.3) 24 h after CABG, with a Δ-FFA of 0.6 mmol/L (Q1-Q3, -0.1 to 1.6). Patients with elevated Δ-FFA levels had a significantly higher ARDS occurrence (55.6% vs. 22.2%; P < 0.001). Elevated Δ-FFA after off-pump CABG correlated with a significantly lower PaO2/FiO2 ratio, prolonged mechanical ventilation, and extended length of ICU stay. The area under the curve (AUC) of Δ-FFA for predicting ARDS (AUC, 0.758; 95% confidence interval, 0.686-0.831) significantly exceeded the AUC of postoperative FFA (AUC, 0.708; 95% CI 0.628-0.788; P < 0.001). CONCLUSIONS: Elevated Δ-FFA levels correlated with ARDS following off-pump CABG. Monitoring FFA may assist in identifying high-risk patients for ARDS, facilitating timely interventions to improve clinical outcomes.

The role of FPR2-mediated ferroptosis in formyl peptide-induced acute lung injury against endothelial barrier damage and protective effect of the mitochondria-derived peptide MOTS-c.

BACKGROUND: Acute lung injury (ALI) has garnered significant attention in the field of respiratory and critical care due to its high mortality and morbidity, and limited treatment options. The role of the endothelial barrier in the development of ALI is crucial. Several bacterial pathogenic factors, including the bacteria-derived formyl peptide (fMLP), have been implicated in damaging the endothelial barrier and initiating ALI. However, the mechanism by which fMLP causes ALI remains unclear. In this study, we aim to explore the mechanisms of ALI caused by fMLP and evaluate the protective effects of MOTS-c, a mitochondrial-derived peptide. METHODS: We established a rat model of ALI and a human pulmonary microvascular endothelial cell (HPMVEC) model of ALI by treatment with fMLP. In vivo experiments involved lung histopathology assays, assessments of inflammatory and oxidative stress factors, and measurements of ferroptosis-related proteins and barrier proteins to evaluate the severity of fMLP-induced ALI and the type of tissue damage in rats. In vitro experiments included evaluations of fMLP-induced damage on HPMVEC using cell activity assays, assessments of inflammatory and oxidative stress factors, measurements of ferroptosis-related proteins, endothelial barrier function assays, and examination of the key role of FPR2 in fMLP-induced ALI. We also assessed the protective effect of MOTS-c and investigated its mechanism on the fMLP-induced ALI in vivo and in vitro. RESULTS: Results from both in vitro and in vivo experiments demonstrate that fMLP promotes the expression of inflammatory and oxidative stress factors, activates ferroptosis and disrupts the vascular endothelial barrier, ultimately contributing to the development and progression of ALI. Mechanistically, ferroptosis mediated by FPR2 plays a key role in fMLP-induced injury, and the Nrf2 and MAPK pathways are involved in this process. Knockdown of FPR2 and inhibition of ferroptosis can attenuate ALI induced by fMLP. Moreover, MOTS-c could protect the vascular endothelial barrier function by inhibiting ferroptosis and suppressing the expression of inflammatory and oxidative stress factors through Nrf2 and MAPK pathways, thereby alleviating fMLP-induced ALI. CONCLUSION: Overall, fMLP disrupts the vascular endothelial barrier through FPR2-mediated ferroptosis, leading to the development and progression of ALI. MOTS-c demonstrates potential as a protective treatment against ALI by alleviating the damage induced by fMLP.

The mitochondrial-derived peptide MOTS-c suppresses ferroptosis and alleviates acute lung injury induced by myocardial ischemia reperfusion via PPARγ signaling pathway.

Acute lung injury (ALI) is a life-threatening complication of cardiac surgery that has a high rate of morbidity and mortality. Epithelial ferroptosis is believed to be involved in the pathogenesis of ALI. MOTS-c has been reported to play a role in regulating inflammation and sepsis-associated ALI. The purpose of this study is to observe the effect of MOTS-c on myocardial ischemia reperfusion (MIR)-induced ALI and ferroptosis. In humans, we used ELISA kits to investigate MOTS-c and malondialdehyde (MDA) levels in patients undergoing off-pump coronary artery bypass grafting (CABG). In vivo, we pretreated Sprague-Dawley rats with MOTS-c, Ferrostatin-1 and Fe-citrate(Ⅲ). We conducted Hematoxylin and Eosin (H&E) staining and detection of ferroptosis-related genes in MIR-induced ALI rats. In vitro, we evaluated the effect of MOTS-c on hypoxia regeneration (HR)-induced mouse lung epithelial-12 (MLE-12) ferroptosis and analyzed the expression of PPARγ through western blotting. We found that circulating MOTS-c levels were decreased in postoperative ALI patients after off-pump CABG, and that ferroptosis contributed to ALI induced by MIR in rats. MOTS-c suppressed ferroptosis and alleviated ALI induced by MIR, and the protective effect of MOTS-c- was dependent on PPARγ signaling pathway. Additionally, HR promoted ferroptosis in MLE-12 cells, and MOTS-c inhibited ferroptosis against HR through the PPARγ signaling pathway. These findings highlight the therapeutic potential of MOTS-c for improving postoperative ALI induced by cardiac surgery.

Long non­coding RNA FER1L4 inhibits cell proliferation and promotes cell apoptosis via the PTEN/AKT/p53 signaling pathway in lung cancer.

Long non­coding RNA Fer­1­like protein 4 (FER1L4) has been reported to play crucial regulatory roles in tumor progression and apoptosis. However, its clinical significance and biological role in non­small cell lung cancer (NSCLC) are completely unknown. The purpose of this study was to investigate the expression of lncRNA FER1L4 in plasma and tissues of patients with NSCLC and study the mechanism of proliferation and apoptosis of lung cancer cells. The expression levels of FER1L4 in plasma and tissues of NSCLC patients and cell lines were analyzed via RT­qPCR. The effects of FER1L4 on cell proliferation, migration and invasion were analyzed by CCK­8, wound healing and Transwell assays, respectively. The expression levels of related proteins were detected by western blot assay, while cell apoptosis was determined by Hoechst staining and flow cytometry. The results revealed that FER1L4 was significantly downregulated in NSCLC plasma and tissues and lung cancer cell lines compared to corresponding controls. Moreover, a significant decrease of cell proliferation, migration and invasion were observed in FER1L4­overexpressed cells. FER1L4 could promote phosphatase and tension homolog deleted on chromosome ten (PTEN) and p53 expression, inhibit AKT phosphorylation expression, thus increasing the proportion of apoptotic cells. The present study indicated that FER1L4 may inhibit cell proliferation and promote apoptosis of NSCLC cells via the PTEN/AKT/p53 pathway, which provides a better understanding of the pathogenesis of NSCLC and may provide a novel potential therapeutic target for clinical treatment.

Clonal Origin Patterns Play a Vital Role in Cardiac Myxoma Recurrence.

OBJECTIVE: To explore the clonal origin pattern of cardiac myxoma and its relationship with recurrence of the disease. METHODS: 20 female patients diagnosed with cardiac myxoma underwent appropriate surgery and were followed-up after the treatment. The DNA of tumor tissues and pairing normal tissues from 20 patients were taken, with polymerase chain reaction (PCR) assay being used to amplify the HUMARA gene on X-chromosome, which could hint the tumor cloning state. Cases were divided into a polyclonal origin group and monoclonal origin group, according to the PCR result. The recurrence rate in the two groups was compared using Fisher's exact probability method. RESULTS: All tumors were successfully removed. PCR assay showed that the hybrid rate in tumors was 90.0% (18/20). Among them, 88.9%(16/18) of cases were identified as polyclonal origin and 11.1%(2/18) were identified as monoclonal origin. After 4 years of follow-up, the recurrence rate was 12.5(2/16) in the polyclonal origin group and 0%(0/2) in monoclonal origin group, with significant difference between the two groups (P<0.05). CONCLUSION: Cardiac myxoma is mostly of polyclonal original, and its polyclonal origin characteristics may contribute to tumor recurrence.

Effects of David I operation in the treatment of aortic root disease combined with aortic insufficiency.

BACKGROUND: We compared the effects of the new David I operation and classical Bentall operation in the treatment of aortic root disease combined with aortic insufficiency. METHODS: A total of 60 cases of patients with aortic root disease combined with aortic insufficiency diagnosed at our hospital from January 2010 to January 2016 were analyzed retrospectively, including 32 cases of aortic root aneurysm, 18 cases of aortic dissection, 5 cases of hypertension combined with atherosclerosis, 2 cases of retrogression, 2 cases of rheumatic heart disease and 1 case of Takayasu arteritis. Twenty-four cases that underwent the David I operation and 36 cases that underwent the Bentall operation were selected and their therapeutic effects were compared. The operation success rate, operation time, cardiopulmonary bypass time, cross-clamp time and blood infusion of both groups were compared; there were no significant differences (P>0.05). RESULTS: Two patients in the David I group and 3 patients in the Bentall operation group died of multiple organ dysfunction. The LVEDd and LVEF of both groups postoperation had no difference when compared with those parameters of before operation. The diameter of the valve annulus after the operation was shorter than before the operation. The severity of valve regurgitation of both groups had no difference. However, the ratio of severe regurgitation of the David I group increased and the mild regurgitation decreased. The incidence rate of complications of the David I group was significantly lower than that of the Bentall operation group. The differences were statistically significant (P<0.05). CONCLUSIONS: Both David I operation and Bentall operation have better short-term and long-term effects in the treatment of aortic root disease when combined with aortic insufficiency; however, David I operation had less long-term complications.

A case report of primary cardiac capillary hemangioma.

BACKGROUND: Hemangioma of the heart, presenting as a primary cardiac tumor is extremely rare. METHODS: We present a 20-year-old male with a cardiac tumor which was incidentally discovered during routine clinical examination. RESULTS: Echocardiography showed a large intramyocardial mass attached to the left ventricle, close to the apex. A tumor was shown near the apex of the left ventricle by Cardiac CT. We performed a total resection surgery of the tumor one week after admission and the patient recovered well and discharged from hospital 7 d after surgery. CONCLUSION: The pathological diagnosis was primary cardiac capillary hemangioma. No tumor recurrence was shown by echocardiography after 20 months follow-up visits.