Fine-tuning activation specificity of G-protein-coupled receptors via automated path searching.

Physics-based simulation methods can grant atomistic insights into the molecular origin of the function of biomolecules. However, the potential of such approaches has been hindered by their low efficiency, including in the design of selective agonists where simulations of myriad protein-ligand combinations are necessary. Here, we describe an automated input-free path searching protocol that offers (within 14 d using Graphics Processing Unit servers) a minimum free energy path (MFEP) defined in high-dimension configurational space for activating sphingosine-1-phosphate receptors (S1PRs) by arbitrary ligands. The free energy distributions along the MFEP for four distinct ligands and three S1PRs reached a remarkable agreement with Bioluminescence Resonance Energy Transfer (BRET) measurements of G-protein dissociation. In particular, the revealed transition state structures pointed out toward two S1PR3 residues F263/I284, that dictate the preference of existing agonists CBP307 and BAF312 on S1PR1/5. Swapping these residues between S1PR1 and S1PR3 reversed their response to the two agonists in BRET assays. These results inspired us to design improved agonists with both strong polar head and bulky hydrophobic tail for higher selectivity on S1PR1. Through merely three in silico iterations, our tool predicted a unique compound scaffold. BRET assays confirmed that both chiral forms activate S1PR1 at nanomolar concentration, 1 to 2 orders of magnitude less than those for S1PR3/5. Collectively, these results signify the promise of our approach in fine agonist design for G-protein-coupled receptors.

Flt3 Activation Mitigates Mitochondrial Fragmentation and Heart Dysfunction through Rebalanced L-OPA1 Processing by Hindering the Interaction between Acetylated p53 and PHB2 in Cardiac Remodeling.

Recent studies have shown that FMS-like receptor tyrosine kinase 3 (Flt3) has a beneficial effect on cardiac maladaptive remodeling. However, the role and mechanism of Flt3 in mitochondrial dynamic imbalance under cardiac stress remains poorly understood. This study aims to investigate how Flt3 regulates p53-mediated optic atrophy 1 (OPA1) processing and mitochondrial fragmentation to improve cardiac remodeling. Mitochondrial fragmentation in cardiomyocytes was induced by isoprenaline (ISO) and H2O2 challenge, respectively, in vitro. Cardiac remodeling in mice was established by ligating the left anterior descending coronary artery or by chronic ISO challenge, respectively, in vivo. Our results demonstrated that the protein expression of acetylated-p53 (ac-p53) in mitochondria was significantly increased under cell stress conditions, facilitating the dissociation of PHB2-OPA1 complex by binding to prohibitin 2 (PHB2), a molecular chaperone that stabilizes OPA1 in mitochondria. This led to the degradation of the long isoform of OPA1 (L-OPA1) that facilitates mitochondrial fusion and resultant mitochondrial network fragmentation. This effect was abolished by a p53 K371R mutant that failed to bind to PHB2 and impeded the formation of the ac-p53-PHB2 complex. The activation of Flt3 significantly reduced ac-p53 expression in mitochondria via SIRT1, thereby hindering the formation of the ac-p53-PHB2 complex and potentiating the stability of the PHB2-OPA1 complex. This ultimately inhibits L-OPA1 processing and leads to the balancing of mitochondrial dynamics. These findings highlight a novel mechanism by which Flt3 activation mitigates mitochondrial fragmentation and dysfunction through the reduction of L-OPA1 processing by dampening the interaction between ac-p53 and PHB2 in cardiac maladaptive remodeling.

Activation of FMS-like tyrosine kinase 3 protects against isoprenaline-induced cardiac hypertrophy by improving autophagy and mitochondrial dynamics.

FMS-like receptor tyrosine kinase 3 (Flt3) expression was reported to increase in the heart in response to pathological stress, but the role of Flt3 activation and its underlying mechanisms remain poorly elucidated. This study was designed to investigate the role of Flt3 activation in sympathetic hyperactivity-induced cardiac hypertrophy and its mechanisms through autophagy and mitochondrial dynamics. In vivo, cardiac hypertrophy was established by subcutaneous injection of isoprenaline (6 mg/kg·day) in C57BL/6 mice for 7 consecutive days. The Flt3-ligand intervention was launched 2 h prior to isoprenaline each day. In vitro, experiments of cardiomyocyte hypertrophy, autophagy, and mitochondrial dynamics were performed in neonatal rat cardiomyocytes (NRCMs). Our results revealed that the expression level of Flt3 protein was significantly increased in the hypertrophic myocardium provoked by isoprenaline administration. Flt3-ligand intervention alleviated isoprenaline-induced cardiac oxidative stress, hypertrophy, fibrosis, and contractile dysfunction. Isoprenaline stimulation impaired autophagic flux in hypertrophic mouse hearts, supported by the accumulation of LC3II and P62 proteins, while Flt3-ligand restored the impairment of autophagic flux. Flt3 activation normalized the imbalance of mitochondrial fission and fusion in the hearts of mice evoked by isoprenaline as evidenced by the neutralization of elevated mitochondrial fission markers and reduced mitochondrial fusion markers. In NRCMs, Flt3-ligand treatment attenuated isoprenaline-stimulated hypertrophy, which was abolished by a Flt3-specific blocker AC220. Activating Flt3 reversed isoprenaline-induced autophagosome accumulation and impairment of autophagic flux probably by enhancing SIRT1 expression and consequently TFEB nuclear translocation. Flt3 activation improved the imbalance of mitochondrial dynamics induced by isoprenaline in NRCMs through the SIRT1/P53 pathway. Activation of Flt3 mitigated ISO-stimulated hypertrophy probably involves the restoration of autophagic flux and balance of mitochondrial dynamics. Therefore, activation of Flt3 attenuates isoprenaline-induced cardiac hypertrophy in vivo and in vitro, the potential mechanism probably attributes to SIRT1/TFEB-mediated autophagy promotion and SIRT1/P53-mediated mitochondrial dynamics balance. These findings suggest that activation of Flt3 may be a novel target for protection against cardiac remodeling and heart failure during sympathetic hyperactivity.

Impaired autophagy and mitochondrial dynamics are involved in Sorafenib-induced cardiomyocyte apoptosis.

Sorafenib (Sor), a novel multi-target anticancer drug also induces severe toxicity in heart, while the mechanism of its cardiotoxicity remains to be fully elucidated. Dysregulation of autophagy and mitochondrial dynamics imbalance have been implicated in cardiomyocyte death. The aim of this study is to test the hypothesis that Sor disrupts autophagy and mitochondrial dynamics, thereby aggravating Sor-induced oxidative stress damage to cardiomyocytes. Our results revealed that Sor (≥ 5 µM) concentration- and time-dependently reduced cell viability and induced apoptosis in H9c2 myoblasts. Sor treatment promoted intracellular reactive oxygen species (ROS) generation, and subsequent Ca2+ overload as well as apoptosis, which were abolished by the ROS scavenger MPG. Sor inhibited the basal autophagy activity of cells, as supported by the fact that ERK1/2 inhibition-dependent decreases of autophagosomes and autolysosomes, and p62 accumulation in a concentration- and time-dependent manner. Improving autophagy with rapamycin abrogated Sor-induced ROS and Ca2+ overloads, and cell apoptosis. Furthermore, Sor compromised mitochondrial morphology and caused excessive mitochondrial fragmentation in cells. The imbalance of mitochondrial dynamics was attributed to ROS-mediated CaMKII overactivity, and increased phosphorylation of dynamin-related protein 1 (phosph-Drp1). Suppression of CaMKII with KN-93 or mitochondrial fission with mitochondrial division inhibitor-1 (Mdivi-1) attenuated Sor-induced ROS and Ca2+ overloads as well as apoptosis. In conclusion, these results provide the first evidence that impairments in autophagy and mitochondrial dynamics are involved in Sor-induced cardiomyocyte apoptosis. The present study may provide a potential strategy for preventing or reducing cardiotoxicity of Sor.

Study on the Role and Mechanism of LncRNA ZFasL in Renal Carcinoma.

Background: Renal carcinoma is the 7th most common cancer in the world, with the 7th and 6th highest incidence and mortality rates worldwide. Although great progress has been made in the diagnosis and treatment of renal carcinoma, its prognosis is still unsatisfactory. It is important to study the molecular mechanisms of renal carcinoma occurrence and development and to find potential therapeutic targets. Objective: The main objective is to investigate the effects of long noncoding RNA (lncRNA) ZFAS1 (lncZFAS1) on the proliferation, apoptosis, and migration of renal carcinoma cells and to preliminarily explore its mechanism. Methods: A qRT-PCR method was used to detect the expression of lncZFAS1 in renal carcinoma tissues and renal carcinoma cells. After shRNA interference with lncZFAS1 expression, the effects of lncZFAS1 on cell proliferation, apoptosis, migration, and invasion were detected by CCK-8 method, flow cytometry, scratch test, and Transwell assay. The effect of the knockdown of lncZFAS1 on the growth of transplanted tumors was examined. The expression of lncZFAS1 in renal carcinoma tissues and renal carcinoma cells was significantly higher than that in paracancerous tissues and normal esophageal epithelial cells. Knockdown of lncZFAS1 significantly inhibited the proliferation, migration, and invasive ability of renal carcinoma cells; upregulated miR-150-5P expression and downregulated HMGA2 expression in renal carcinoma cells; and significantly inhibited the growth of transplanted tumors in nude mice. Conclusion: Upregulation of miR-150-5P expression was detected after knockdown of lncZFAS1 in renal carcinoma cells, while both mRNA and protein expression levels of HMGA2 were decreased. lncZFAS1 can promote the proliferation and migration of renal carcinoma cells, and the mechanism may be related to the regulation of the miR-150-5P/HMGA2 molecular axis.

Clinical research analysis based on prostate cancer screening diagnosis.

This study aimed to analyse the clinical characteristics and risk factors of patients with positive prostate biopsy at 4-20 ng/mL of prostate-specific antigen (PSA), construct a new parameter based on this characteristics and assess its diagnostic value for prostate cancer (PCa). Logistic regression analysis was used to clarify the risk factors of PCa, and a new parameter based on the results was constructed. Compare the diagnostic value of various diagnostic parameters for PCa. Logistic multivariate regression analysis revealed that age (OR, 5.269; 95%CI, 2.762-10.050), comorbid diabetes (OR, 2.437; 95%CI, 1.162-5.111), PSA (OR, 2.462; 95%CI, 1.198-5.059) and prostate volume (PV) (OR, 0.227; 95%CI, 0.100-0.516) are risk factors for PCa. The age, PSA and PV of patients were combined to construct a new parameter, that is A-PSAD = (age × total PSA [TPSA])/PV]. The area under the receiver-operating characteristic curve(AUC) of A-PSAD (0.728) for PCa diagnosis was higher than the AUCs of TPSA (0.581), free prostate-specific antigen (0.514), (F/T)PSA (0.535) and PSAD (0.696), with significant differences. Age, history of diabetes, TPSA and PV are risk factors for PCa(PSA:4-20ng/mL); in addition, A-PSAD has a moderate diagnostic value for PCa and may become a new indicator for PCa screening.

Association between Phenotypic Age and Mortality in Patients with Multivessel Coronary Artery Disease.

BACKGROUND: Chronological age (CA) is not a perfect proxy for the true biological aging status of the body. A new biological aging measure, phenotypic age (PhenoAge), has been shown to capture morbidity and mortality risk in the general US population and diverse subpopulations. This study was aimed at evaluating the association between PhenoAge and long-term outcome of patients with multivessel coronary artery disease (CAD). METHODS: A total of 609 multivessel CAD patients who received PCI attempt and with follow-up were enrolled. The clinical outcome was all-cause mortality on follow-up. PhenoAge was calculated using an equation constructed from CA and 9 clinical biomarkers. Cox proportional hazards regression models and receiver operating characteristic (ROC) curves were performed to evaluate the association between PhenoAge and mortality. RESULTS: Overall, patients with more diseases had older PhenoAge and phenotypic age acceleration (PhenoAgeAccel). After a median follow-up of 33.5 months, those with positive PhenoAgeAccel had a significantly higher incidence of all-cause mortality (P = 0.001). After adjusting for CA, Cox proportional hazards models showed that both PhenoAge and PhenoAgeAccel were significantly associated with all-cause mortality. Even after further adjusting for confounding factors, each 10-year increase in PhenoAge was also associated with a 51% increased mortality risk. ROC curves revealed that PhenoAge, with an area under the curve of 0.705, significantly outperformed CA, the individual clinical chemistry measure, and other risk factors. When reexamining the ROC curves using various combinations of variables, we found that PhenoAge provides additional predictive power to all models. CONCLUSIONS: In conclusion, PhenoAge was strongly associated with all-cause mortality even after adjusting for CA. Our findings suggest that PhenoAge measure may be complementary in predicting mortality risk for patients with multivessel CAD.

Association between sarcopenia and cardiovascular disease among middle-aged and older adults: Findings from the China health and retirement longitudinal study.

BACKGROUND: Little is known about the association between sarcopenia and cardiovascular disease (CVD) among middle-aged and older adults. Using the nationally representative data from the China Health and Retirement Longitudinal Study (CHARLS), we conducted cross-sectional and longitudinal analyses to investigate the association between sarcopenia status and CVD in middle-aged and older Chinese population. METHODS: The sample comprised 15,137 participants aged at least 45 years from the CHARLS 2015. Sarcopenia status was defined according to the Asian Working Group for Sarcopenia 2019 (AWGS 2019) criteria. CVD was defined as the presence of physician-diagnosed heart disease and/or stroke. A total of 11,863 participants without CVD were recruited from the CHARLS 2015 and were followed up in 2018. Cox proportional hazards regression models were conducted to examine the effect of sarcopenia on CVD. FINDINGS: The pre valence of CVD in total populations, no-sarcopenia, possible sarcopenia and sarcopenia individuals were 12.6% (1905/15,137), 10.0% (1026/10,280), 18.1% (668/3685), 18.0% (211/1172), respectively. Both possible sarcopenia [OR (95% CI): 1.29 (1.13-1.48)] and sarcopenia [1.72 (1.40-2.10)] were associated with CVD in total populations. During the 3.6 years of follow-up, 1,273 cases (10.7%) with incident CVD were identified. In the longitudinal analysis, individuals with the diagnosis of possible sarcopenia (HR:1.22, 95% CI: 1.05-1.43) and sarcopenia participants (HR:1.33, 95% CI: 1.04-1.71) were more likely to have new onset CVD than no-sarcopenia peers. INTERPRETATION: Both possible sarcopenia and sarcopenia, assessed using the AWGS 2019 criteria, were associated with higher CVD risk among middle-aged and older Chinese adults. FUNDING: None.

The influence of age on prostate cancer screening index.

PURPOSE: This study aimed to identify parameters with a higher diagnostic value for early screening of prostate cancer (PCa) at different ages. MATERIALS AND METHODS: A total of 294 patients were included and divided into two groups according to the age of patients (≤66 and >66 years). Receiver operating characteristic (ROC) curves of total prostate-specific antigen (TPSA), free PSA (FPSA), (F/T)PSA, PSA density (PSAD), PSA-AV score, the ratio of patients' age to prostate volume (AVR) and (F/T)/PSAD were constructed. The area under the ROC curve (AUC) was calculated, and differences in the AUC values among the above-mentioned parameters were compared. RESULTS: There were 121 patients in the ≤66 years age group (benign prostatic hyperplasia BPH, 103 patients; PCa 18 patients) and 173 patients in the >66 years age group (BPH, 100 patients; PCa, 73 patients). In the ≤66 years age group, the AUC value of AVR for PCa diagnosis was the highest; however, there was no statistically significant difference compared with the AUC values of PSAD and (F/T)/PSAD; compared with TPSA, FPSA, (F/T)PSA and PSA-AV, the differences were statistically significant. In the >66 years age group, the AUC values of PSAD and PSA-AV for PCa diagnosis were higher than those of TPSA, FPSA, (F/T)PSA and (F/T)/PSAD, and the difference was statistically significant; however, the difference was not statistically significant when compared with the AUC value of AVR. CONCLUSION: In different age groups, screening indices for PCa diagnosis should be selected according to the age of patients.

Association Between Sarcopenia and Depressive Symptoms in Chinese Older Adults: Evidence From the China Health and Retirement Longitudinal Study.

Background: Little is known about whether sarcopenia predicts incident depressive symptoms in older adults. Using the nationally representative data from the China Health and Retirement Longitudinal Study (CHARLS), we conducted cross-sectional and longitudinal analyses to estimate the association between sarcopenia and depressive symptoms among older adults. Methods: The sample comprised 7,706 participants aged at least 60 years (50.6% women; mean age 68.0 ± 6.5) from the CHARLS 2015. Based on the Asian Working Group for Sarcopenia 2019 (AWGS 2019) criteria, sarcopenia status was classified into three types: no-sarcopenia, possible sarcopenia, and sarcopenia. Depressive symptoms were assessed using the validated 10-items of the Center for Epidemiologic Studies Depression Scale. A cross-sectional analysis was used to examine the relationship between sarcopenia status and depressive symptoms. A total of 4,652 participants without depressive symptoms were recruited from the same cohort in 2015 and were followed up in 2018. Cox proportional hazards regression models were conducted to examine the effect of sarcopenia status on subsequent depressive symptoms with the report of hazard ratio (HR). Results: The prevalence of depressive symptoms in total populations, no-sarcopenia, possible sarcopenia, and sarcopenia individuals were 27.1% (2085/7706), 21.5% (927/4310), 33.6% (882/2627), and 35.9% (276/769), respectively. Both possible sarcopenia (OR: 1.75, 95% CI: 1.46-2.10) and sarcopenia (OR: 1.64, 95% CI: 1.23-2.19) were positively associated with higher odds of depressive symptoms (all p < 0.01). During the 3.7 years of follow-up, 956 cases (20.6%) with incident depressive symptoms were identified. In the longitudinal analysis, individuals with the diagnosed possible sarcopenia (HR: 1.27, 95% CI: 1.01-1.58) and sarcopenia participants (HR: 1.49, 95% CI: 1.06-2.09) were more likely to have new onset depressive symptoms than no-sarcopenia peers. Conclusions: Both possible sarcopenia and sarcopenia, assessed using the AWGS 2019 criteria, were independent predictors for the occurrence of depressive symptoms among Chinese older adults. Our findings provided new evidence supporting the longitudinal connection between sarcopenia and mental health problems, it also provides further justification for timely identification and management of both possible sarcopenia and sarcopenia as part of comprehensive strategies to fight against depressive symptoms.

Downregulation of miR-128 Ameliorates Ang II-Induced Cardiac Remodeling via SIRT1/PIK3R1 Multiple Targets.

Recent studies reported that miR-128 was differentially expressed in cardiomyocytes in response to pathologic stress. However, its function and mechanism remain to be fully elucidated. The aim of the present study was to investigate the role of miR-128 in chronic angiotensin II (Ang II) infusion-induced cardiac remodeling and its underlying mechanism. The cardiac remodeling and heart failure in vivo were established in C57BL/6 mice by chronic subcutaneous Ang II delivery. Knocking down miR-128 was conducted in the hearts of the mice by intravenous injection of HBAAV2/9-miR-128-GFP sponge (miR-128 inhibitor). In vitro experiments of cardiac hypertrophy, apoptosis, and aberrant autophagy were performed in cultured cells after Ang II treatment or transfection of miR-128 antagomir. Our results showed that chronic Ang II delivery for 28 days induced cardiac dysfunction, hypertrophy, fibrosis, apoptosis, and oxidative stress in the mice, while the miR-128 expression was notably enhanced in the left ventricle. Silencing miR-128 in the hearts of mice ameliorated Ang II-induced cardiac dysfunction, hypertrophy, fibrosis apoptosis, and oxidative stress injury. Moreover, Ang II induced excessive autophagy in the mouse hearts, which was suppressed by miR-128 knockdown. In cultured cells, Ang II treatment induced a marked elevation in the miR-128 expression. Downregulation of miR-128 in the cells by transfection with miR-128 antagomir attenuated Ang II-induced apoptosis and oxidative injury probably via directly targeting on the SIRT1/p53 pathway. Intriguingly, we found that miR-128 inhibition activated PIK3R1/Akt/mTOR pathway and thereby significantly damped Ang II-stimulated pathological autophagy in cardiomyocytes, which consequently mitigated cell oxidative stress and apoptosis. In conclusion, downregulation of miR-128 ameliorates Ang II-provoked cardiac oxidative stress, hypertrophy, fibrosis, apoptosis, and dysfunction in mice, likely through targeting on PIK3R1/Akt/mTORC1 and/or SIRT1/p53 pathways. These results indicate that miR-128 inhibition might be a potent therapeutic strategy for maladaptive cardiac remodeling and heart failure.

Inhibition of the Ras/ERK1/2 pathway contributes to the protective effect of ginsenoside Re against intimal hyperplasia.

Neointimal hyperplasia is the major cause of carotid stenosis after vascular injury, which restricts the long-term efficacy of endovascular treatment and endarterectomy in preventing stenosis. Ginsenoside Re (Re) is a major active ingredient of ginseng having multifaceted pharmacological effects on the cardiovascular system, and is a potential treatment for restenosis. In this study, we demonstrated that Re treatment significantly inhibited vascular injury-induced neointimal thickening, reduced the intimal area and intima/media (I/M) ratio, increased the lumen area, and inhibited pro-inflammatory cytokines. In cultured A7R5 cells, Re inhibited LPS-induced proliferation and migration as evidenced by suppressed colony formation and shortened migration distance, accompanied by the downregulated expression of pro-inflammatory cytokines. Re promoted VSMC apoptosis induced by balloon injury in vivo and LPS challenge in vitro. Moreover, Re inhibited autophagy in VSMCs evoked by balloon injury and LPS as supported by reduced LC3II and increased p62 expressions. Suppression of autophagy with the specific autophagy inhibitor spautin-1 efficiently inhibited LPS-induced cell proliferation and inflammation and promoted caspase-3/7 activities. Mechanistically, we found that Re attenuated Ras/ERK1/2 expression in VSMCs in vivo and in vitro. The MEK1/2 inhibitor PD98059 showed similar effects to Re on cell proliferation, migration, apoptosis, and the levels of autophagy and cytokines. In conclusion, we provided significant evidence that Re inhibited vascular injury-induced neointimal thickening probably by promoting VSMC apoptosis and inhibiting autophagy via suppression of the Ras/MEK/ERK1/2 signaling pathway.

The predictive value of the ratio of the product of neutrophils and hemoglobin to lymphocytes in non-muscular invasive bladder cancer patients with postoperative recurrence.

PURPOSE: The purpose of this study was to explore the predictive value of the ratio of the product of neutrophils and hemoglobin to lymphocytes (NHL) in patients with non-muscular invasive bladder cancer (NMIBC). MATERIALS AND METHODS: We retrospectively collected clinical and pathological data of patients with NMIBC who underwent transurethral resection of bladder tumor (TURBT) at our hospital between 2013 and 2018. The ratio of neutrophils to lymphocytes (NLR), the Systemic Immune Inflammation Index (SII), and NHL were obtained based on routine blood settlement within a week before surgery. The receiver operating characteristic curve was used to determine the optimal cutoff value of each index, and different groups were grouped accordingly. Kaplan-Meier survival curve and Cox regression model were used to study the factors affecting the prognosis of NMIBC patients. RESULTS: There was significant difference in recurrence-free survival (RFS) rate between the high NLR group and the low NLR group, the high SII group and the low SII group, and the high NHL group and the low NHL group. Cox univariate regression analysis showed that tumor number, tumor size, tumor pathological grade, tumor pathological stage, NLR, SII, and NHL were related to postoperative RFS in patients with NMIBC. The tumor number, tumor pathological grade, SII, and NHL were independent predictors of RFS in multivariate analysis. CONCLUSIONS: The preoperative clinical inflammatory indexes NLR, SII, and NHL have certain predictive value for postoperative RFS in NMIBC patients.

Discovery of novel quinazoline derivatives as potent PI3Kδ inhibitors with high selectivity.

Inhibition of PI3Kδ has been proved to be an efficacious strategy for the treatment of hematological malignancies where the PI3K/Akt signaling pathway is hyperactive. Herein, a series of quinazoline derivatives bearing acrylamide fragment were prepared using skeleton-deconstruction strategy. The preliminary bioactivity evaluation resulted in the discovery of lead compound 15c. Compound 15c exhibited excellent enzyme activity against PI3Kδ (IC50 = 27.5 nM) compared with BEZ235 as well as the significant anti-proliferation activities. With the high selectivity over other PI3K isoforms and potent effects on PI3K/Akt pathway, 15c can be identified as a promising PI3Kδ inhibitor worthy of further profiling.

Activated FMS-like tyrosine kinase 3 ameliorates angiotensin II-induced cardiac remodelling.

AIM: FMS-like receptor tyrosine kinase 3 (Flt3) has been reported to be increased in cardiomyocytes responding to ischaemic stress. This study was to determine whether Flt3 activation could ameliorate pressure overload-induced heart hypertrophy and fibrosis, and to elucidate the mechanisms of action. METHODS: In vivo cardiac hypertrophy and remodelling experiments were conducted by infusing angiotensin II (Ang II) chronically in male C57BL/6 mice. Flt3-specific ligand (FL) was administered intraperitoneally every two days (5 µg/mouse). In vitro experiments on hypertrophy, apoptosis and autophagy mechanism were performed in neonatal rat cardiomyocytes (NRCMs) and H9c2 cells with adenovirus vector-mediated overexpression of Flt3. RESULTS: Our results demonstrated that following chronic Ang II infusion for 4 weeks, the mice exhibited heart hypertrophy, fibrosis, apoptosis and contractile dysfunction. Meanwhile, Ang II induced autophagic responses in mouse hearts, as evidenced by increased LC3 II and decreased P62 expression. These pathological alterations in Ang II-treated mice were significantly ameliorated by Flt3 activation with FL administration. In NRCMs and Flt3-overexpressed H9c2 cells, FL attenuated Ang II-induced pathological autophagy and inactivated AMPK/mTORC1/FoxO3a signalling, thereby efficiently mitigating cell hypertrophy and apoptosis. Conversely, the AMPK activator metformin or the mTORC1 inhibitor rapamycin reversed the effects of FL on the alterations of autophagy, hypertrophy and apoptosis in cardiomyocytes induced by Ang II. CONCLUSION: Flt3 activation ameliorates cardiac hypertrophy, fibrosis and contractile dysfunction in the mouse model of chronic pressure overload, most likely via suppressing AMPK/mTORC1/FoxO3a-mediated autophagy. These results provide new evidence supporting Flt3 as a novel therapeutic target in maladaptive cardiac remodelling.

Cardiotoxicity of sorafenib is mediated through elevation of ROS level and CaMKII activity and dysregulation of calcium homoeostasis.

Sorafenib, a multi-kinase inhibitor, is recommended as a new standard therapy for advanced hepatocellular carcinoma (HCC); however, it also exhibits severe cardiotoxicity and the toxicity mechanisms are not completely elucidated. Recent studies suggested that sorafenib-enhanced ROS may partially contribute to its anti-HCC effect, which implies that redox mechanism might also be involved in sorafenib's cardiotoxicity. In this study, we aimed to investigate if sorafenib is able to induce oxidative stress and how this may impair cellular functions in cardiomyocyte, ultimately accounting for its cardiotoxicity. Our results showed that in isolated rat hearts, sorafenib caused ventricular arrhythmias and left ventricular dysfunction, which were alleviated by the antioxidant N-(2-mercaptopropionyl)-glycine (MPG). In isolated ventricular myocytes, sorafenib increased diastolic intracellular Ca2+ levels, decreased Ca transients and the occurrence of Ca2+ waves. These changes were eliminated by MPG, CaMKII inhibitor KN-93 and the mitochondrial permeability transition pore (mPTP)inhibitor cyclosporin A (CsA). Moreover, the levels of oxidized and phosphorylated CaMKII were significantly increased. Sorafenib elevated ROS levels, which was reversed by CsA and MPG; additionally, sorafenib reduced the activity of mitochondrial complex III and augmented mitochondrial ROS production. In vivo rats treated with sorafenib exhibited a reduction of antioxidant defence and abnormal histological alterations including hypertrophy, increased fibrosis, disordered myofibrils and damaged mitochondria, which were protected by MPG. We conclude that sorafenib induces the disruption of Ca2+ homoeostasis and cardiac injury via enhanced ROS potentially through inhibiting mitochondrial complex III, the opening of mPTP and overactivating CaMKII. These results provide a potential strategy for preventing or reducing cardiotoxicity of sorafenib.

Fractal zone plate beam based optical tweezers.

We demonstrate optical manipulation with an optical beam generated by a fractral zone plate (FZP). The experimental results show that the FZP beam can simultaneously trap multiple particles positioned in different focal planes of the FZP beam, owing to the multiple foci and self-reconstruction property of the FZP beam. The FZP beam can also be used to construct three-dimensional optical tweezers for potential applications.

Protective Effect of Ginsenoside Rg1 on Bleomycin-Induced Pulmonary Fibrosis in Rats: Involvement of Caveolin-1 and TGF-ß1 Signal Pathway.

Idiopathic pulmonary fibrosis (IPF) is a progressive disease with poor prognosis and high mortality rate. Panax Notoginseng Saponins (PNS), extracted from Panax Notoginseng as a traditional Asian medicine, displayed a significant anti-fibrosis effect in liver and lung. However, whether Ginsenoside Rg1 (Rg1), an important and active ingredient of PNS, exerts anti-fibrotic activity on IPF still remain unclear. In this study, we investigated the effect of Rg1 on bleomycin-induced pulmonary fibrosis in rats. Bleomycin (5 mg/kg body weight) was intratracheally administrated to male rats. Rg1 (18, 36 and 72 mg/kg) was orally administered on the next day after bleomycin. Lungs were harvested at day 7 and 28 for the further experiments. Histological analysis revealed that bleomycin successfully induced pulmonary fibrosis, and that Rg1 restored the histological alteration of bleomycin-induced pulmonary fibrosis (PF), significantly decreased lung coefficient, scores of alveolitis, scores of PF as well as contents of alpha smooth muscle actin (α-SMA) and hydroxyproline (Hyp) in a dose-dependent manner in PF rats. Moreover, Rg1 increased the expression levels of Caveolin-1 (Cav-1) mRNA and protein, lowered the expression of transforming growth factor-ß1 (TGF-ß1) mRNA and protein in the lung tissues of PF rats. These data suggest that Rg1 exhibits protective effect against bleomycin-induced PF in rats, which is potentially associated with the down-regulation of TGF-ß1 and up-regulation of Cav-1.

Composite Thue-Morse zone plates.

We present a new family of diffractive lenses, composite Thue-Morse zone plates (CTMZPs), formed by multiple orders of Thue-Morse zone plates (TMZPs). The typical structure of a CTMZP is a composite of two concentric TMZPs. The focusing properties of the CTMZPs with different parameters have been investigated both theoretically and experimentally. Compared with the TMZPs, the CTMZPs have higher performance in axial intensity and imaging resolution. The CTMZP beams are also found to possess the self-reconstruction property, and would be useful for three-dimensional optical tweezers, laser machining, and optical imaging.