Long-term efficacy, safety and biocompatibility of a novel sirolimus eluting iron bioresorbable scaffold in a porcine model.

Iron is considered as an attractive alternative material for bioresorbable scaffolds (BRS). The sirolimus eluting iron bioresorbable scaffold (IBS), developed by Biotyx Medical (Shenzhen, China), is the only iron-based BRS with an ultrathin-wall design. The study aims to investigate the long-term efficacy, safety, biocompatibility, and lumen changes during the biodegradation process of the IBS in a porcine model. A total of 90 IBSs and 70 cobalt-chromium everolimus eluting stents (EES) were randomly implanted into nonatherosclerotic coronary artery of healthy mini swine. The multimodality assessments including coronary angiography, optical coherence tomography, micro-computed tomography, magnetic resonance imaging, real-time polymerase chain reaction (PCR), and histopathological evaluations, were performed at different time points. There was no statistical difference in area stenosis between IBS group and EES group at 6 months, 1year, 2 years and 5 years. Although the scaffolded vessels narrowed at 9 months, expansive remodeling with increased mean lumen area was found at 3 and 5 years. The IBS struts remained intact at 6 months, and the corrosion was detectable at 9 months. At 5 years, the iron struts were completely degraded and absorbed in situ, without in-scaffold restenosis or thrombosis, lumen collapse, aneurysm formation, and chronic inflammation. No local or systemic toxicity and abnormal histopathologic manifestation were found in all experiments. Results from real-time PCR indicated that no sign of iron overload was reported in scaffolded segments. Therefore, the IBS shows comparable efficacy, safety, and biocompatibility with EES, and late lumen enlargement is considered as a unique feature in the IBS-implanted vessels.

Testis specific protein, Y-encoded-like 2 activates JAK2/STAT3 pathway in hypothalamic paraventricular nucleus to sustain hypertension.

BACKGROUND: In the hypothalamic paraventricular nucleus (PVN) of spontaneously hypertensive rats (SHRs), the expression of Testis specific protein, Y-encoded-like 2 (TSPYL2) and the phosphorylation level of Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) are higher comparing with the normotensive Wistar-Kyoto rats (WKY). But how they are involved in hypertension remains unclear. TSPYL2 may interact with JAK2/STAT3 in PVN to sustain the high blood pressure during hypertension. METHODS: Knockdown of TSPYL2 via adeno-associated virus (AAV) carrying shRNA was conducted through bilateral micro-injection into the PVN of SHR and WKY rats. JAK2/STAT3 inhibition was achieved by intraperitoneally or PVN injection of AG490 into the SHRs. Blood pressure (BP), plasma norepinephrine (NE), PVN inflammatory response, and PVN oxidative stress were measured. RESULTS: TSPYL2 knock-down in the PVN of SHRs but not WKYs led to reduced BP and plasma NE, and deactivation of JAK2/STAT3, decreased expression of pro-inflammatory cytokine IL-1ß, and increased expression of anti-inflammatory cytokine IL-10 in the PVN. Meanwhile, AG490 administrated in both ways reduced the blood pressure in the SHRs and deactivated JAK2/STAT3 but failed to change the expression of TSPYL2 in PVN. AG490 also downregulated expression of IL-1ß and upregulated expression of IL-10. Both knockdown of TSPYL2 and inhibition of JAK2/STAT3 can reduce the oxidative stress in the PVN of SHRs. CONCLUSION: JAK2/STAT3 is regulated by TSPYL2 in the PVN of SHRs, and PVN TSPYL2/JAK2/STAT3 is essential for maintaining high blood pressure in the hypertensive rats, making it a potential therapeutic target for hypertension.

IiAGL6 participates in the regulation of stamen development and pollen formation in Isatis indigotica.

The AGL6 (AGMOUSE LIKE 6) gene is a member of the SEP subfamily and functions as an E-class floral homeotic gene in the development of floral organs. In this study, we cloned IiAGL6, the orthologous gene of AGL6 in Isatis indigotica. The constitutive expression of IiAGL6 in Arabidopsis thaliana resulted in a late-flowering phenotype and the development of curly leaves during the vegetative growth period. Abnormal changes in floral organ development were observed during the reproductive stage. In woad plants, suppression of IiAGL6 using TRV-VIGS (tobacco rattle virus-mediated virus-induced gene silencing) decreased the number of stamens and led to the formation of aberrant anthers. Similar changes in stamen development were also observed in miRNA-AGL6 transgenic Arabidopsis plants. Yeast two-hybrid and BiFC tests showed that IiAGL6 can interact with other MADS-box proteins in woad; thus, playing a key role in defining the identities of floral organs, particularly during stamen formation. These findings might provide novel insights and help investigate the biological roles of MADS transcription factors in I. indigotica.

Proximal vs Extensive Repair in Acute Type A Aortic Dissection Surgery.

BACKGROUND: This purpose of this study was to evaluate the impact of proximal vs extensive repair on mortality and how this impact is influenced by patient characteristics. METHODS: Of 5510 patients with acute type A aortic dissection from 13 Chinese hospitals (2016-2021) categorized by proximal vs extensive repair, 4038 patients were used for for model derivation using eXtreme gradient boosting and 1472 patients for model validation. RESULTS: Operative mortality of extensive repair was higher than proximal repair (10.4% vs 2.9%; odd ratio [OR], 3.833; 95% CI, 2.810-5.229; P < .001) with a number needed to harm of 15 (95% CI, 13-19). Seven top features of importance were selected to develop an alphabet risk model (age, body mass index, platelet-to-leucocyte ratio, albumin, hemoglobin, serum creatinine, and preoperative malperfusion), with an area under the curve of 0.767 (95% CI, 0.733-0.800) and 0.727 (95% CI, 0.689-0.764) in the derivation and validation cohorts, respectively. The absolute rate differences in mortality between the 2 repair strategies increased progressively as predicted risk rose; however it did not become statistically significant until the predicted risk exceeded 4.5%. Extensive repair was associated with similar risk of mortality (OR, 2.540; 95% CI, 0.944-6.831) for patients with a risk probability < 4.5% but higher risk (OR, 2.164; 95% CI, 1.679-2.788) for patients with a risk probability > 4.5% compared with proximal repair. CONCLUSIONS: Extensive repair is associated with higher mortality than proximal repair; however it did not carry a significantly higher risk of mortality until the predicted probability exceeded a certain threshold. Choosing the right surgery should be based on individualized risk prediction and treatment effect. (ClinicalTrials.gov no. NCT04918108.).

Multi-Omics Reveal Additive Cytotoxicity Effects of Aflatoxin B1 and Aflatoxin M1 toward Intestinal NCM460 Cells.

Aflatoxin B1 (AFB1) is a common crop contaminant, while aflatoxin M1 (AFM1) is implicated in milk safety. Humans are likely to be simultaneously exposed to AFB1 and AFM1; however, studies on the combined interactive effects of AFB1 and AFM1 are lacking. To fill this knowledge gap, transcriptomic, proteomic, and microRNA (miRNA)-sequencing approaches were used to investigate the toxic mechanisms underpinning combined AFB1 and AFM1 actions in vitro. Exposure to AFB1 (1.25-20 µM) and AFM1 (5-20 µM) for 48 h significantly decreased cell viability in the intestinal cell line, NCM460. Multi-omics analyses demonstrated that additive toxic effects were induced by combined AFB1 (2.5 µM) and AFM1 (2.5 µM) in NCM460 cells and were associated with p53 signaling pathway, a common pathway enriched by differentially expressed mRNAs/proteins/miRNAs. Specifically, based on p53 signaling, cross-omics showed that AFB1 and AFM1 reduced NCM460 cell viability via the hsa-miR-628-3p- and hsa-miR-217-5p-mediated regulation of cell surface death receptor (FAS), and also the hsa-miR-11-y-mediated regulation of cyclin dependent kinase 2 (CDK2). We provide new insights on biomarkers which reflect the cytotoxic effects of combined AFB1 and AFM1 toxicity.

Metabolomic Analysis Reveals the Mechanisms of Hepatotoxicity Induced by Aflatoxin M1 and Ochratoxin A.

Aflatoxin M1 (AFM1) is the only toxin with the maximum residue limit in milk, and ochratoxin A (OTA) represents a common toxin in cereals foods. It is common to find the co-occurrence of these two toxins in the environment. However, the interactive effect of these toxins on hepatoxicity and underlying mechanisms is still unclear. The liver and serum metabolomics in mice exposed to individual AFM1 at 3.5 mg/kg b.w., OTA at 3.5 mg/kg b.w., and their combination for 35 days were conducted based on the UPLC-MS method in the present study. Subsequent metabolome on human hepatocellular liver carcinoma (Hep G2) cells was conducted to narrow down the key metabolites. The phenotypic results on liver weight and serum indicators, such as total bilirubin and glutamyltransferase, showed that the combined toxins had more serious adverse effects than an individual one, indicating that the combined AFM1 and OTA displayed synergistic effects on liver damage. Through the metabolic analysis in liver and serum, we found that (i) a synergistic effect was exerted in the combined toxins, because the number of differentially expressed metabolites on combination treatment was higher than the individual toxins, (ii) OTA played a dominant role in the hepatoxicity induced by the combination of AFM1, and OTA and (iii) lysophosphatidylcholines (LysoPCs), more especially, LysoPC (16:1), were identified as the metabolites most affected by AFM1 and OTA. These findings provided a new insight for identifying the potential biomarkers for the hepatoxicity of AFM1 and OTA.

[Effect of Rheb1 in the Development of Mouse Megakaryocyte-Erythroid Progenitor Cells].

OBJECTIVE: To investigate the effect of Rheb1 in the development of mouse megakaryocyte-erythroid progenitor cells and its related mechanism. METHODS: Rheb1 was specifically knocked-out in the hematopoietic system of Vav1-Cre;Rheb1fl/fl mice(Rheb1Δ/Δ mice). Flow cytometry was used to detect the percentage of red blood cells in peripheral blood and erythroid cells in bone marrow in Vav1-Cre;Rheb1fl/fl mice and control mice. The CFC assay was used to detect the differentiation ability of Rheb1 KO megakaryocyte-erythroid progenitor cells and control cells. Real-time fluorescence quantification PCR was used to detect the relative expression of PU.1,GATA-1,GATA-2,CEBPα and CEBPß of Rheb1 KO megakaryocyte-erythroid progenitor cells and control cells. Rapamycin was added to the culture medium, and it was used to detect the changes in cloning ability of megakaryocyte-erythroid progenitor cells from wild-type mice in vitro. RESULTS: After Rheb1 was knocked out, the development and stress response ability of megakaryocyte-erythroid progenitor cells in mice were weaken and the differentiation ability of megakaryocyte-erythroid progenitor cells in vitro was weaken. Moreover, the expression of GATA-1 of megakaryocyte-erythroid progenitor cells was decreased. Further, rapamycin could inhibit the differentiative capacity of megakaryocyte-erythroid progenitor cells in vitro. CONCLUSION: Rheb1 can regulate the development of megakaryocyte-erythroid progenitor cells probably through the mTOR signaling pathway in mice.

Cannabinoid receptor agonist WIN55212-2 reduces unpredictable mild stress-induced depressive behavior of rats.

BACKGROUND: Depression is a neurological disorder characterized by persistent low mood. A number of studies have suggested that the use of type 1 cannabinoid receptor (CB1R) agonists can reduce depressive behavior, but its effect on the depressive behavior and nerve damage of rats exposed to chronic unpredictable mild stress (CUMS) has not been reported. METHODS: Rats were exposed to CUMS for 4 weeks to induce depressive behavior. Male Sprague-Dawley (SD) rats aged 6-8 weeks were randomly divided into six groups: control group (control), depression group (CUMS), depression + fluoxetine group (Flu), depression + WIN55212-2 group (WIN), depression + NF-κB inhibitor group (PDTC), and depression + WIN + PDTC group (WIN + PDTC). We performed four behavioral experiments test to evaluate the depressive behaviors of rats. Hematoxylin and eosin (HE) and Nissl staining were performed to observe the neuron structures of the hippocampus. Enzyme-linked immunosorbent assay (ELISA) was used to measure the concentrations of interleukin-1ß (IL-1ß), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and cyclooxygenase-2 (COX-2). Biochemical experiments were performed to evaluate the concentrations of nitric oxide (NO), malondialdehyde (MDA), reactive oxygen species (ROS), and superoxide dismutase (SOD). Fluorescence quantitative PCR was used to detect the mRNA expression of brain-derived neurotrophic factor (BDNF), tyrosine kinase receptor B (TrkB), and inducible nitric oxide synthase (iNOS) in the hippocampus, and western blot was performed to detect protein expression levels related to the NF-κB signaling pathway in the hippocampus. RESULTS: Compared with the normal control group, CUMS significantly induced abnormal behaviors in stressed rats. The concentrations of pro-inflammatory factors and oxidative stress injury factors in the hippocampus of the CUMS group increased significantly. The interventions of Flu, WIN, and PDTC significantly reduced neuroinflammation and oxidative stress injury. Compared with the WIN group, the WIN + PDTC intervention group had better results. In addition, WIN could significantly inhibit the activation of the NF-κB signaling pathway. CONCLUSIONS: This study showed that cannabinoid receptor agonists can reduce the CUMS-induced depressive behaviors of rats by blocking the NF-κB signaling pathway to alleviate neuroinflammation and oxidative stress injury.

Development of novel affinity reagents for detecting protein tyrosine phosphorylation based on superbinder SH2 domain in tumor cells.

Tyrosine phosphorylation, as a hallmark in cellular signal transduction, is important for a diverse array of cellular processes, such as proliferation, metabolism, motility, and survival. Aberrant tyrosine phosphorylation plays a causal role in many diseases, especially the cancer. Detecting protein phosphorylation status in the cancer cells or tissues is vital for assessing the pathological phase, discovering the cancer biomarkers, and identifying the drug targets. However, the common biochemical detection methods remain through anti-pTyr antibodies, which are known to have limited sensitivity, poor reproducibility and high cost. Recent studies have proved that superbinder SH2 domain is a good replacement of anti-pTyr antibodies for the specific enrichment of pTyr peptides in phosphoproteomics analysis. In this work, we exploited a series of affinity reagents based on superbinder SH2 derived from Src protein for detecting the pTyr-containing proteins to replace anti-pY antibodies in immunoblotting and immunofluorescence techniques. The excellent performance of HRP-sSH2 and EGFP-sSH2 was verified by the analysis of several different tumor cell samples and was compared with most commonly used commercial antibodies. EGFP-sSH2-(Arg)9 might be applied as the probe for direct fluorescence imaging in live cells via efficiently penetrating cell membranes and specifically binding with pTyr proteins. In summary, we have developed three novel, convenient, sensitive, and cost-effective affinity reagents that would have wide applications in protein tyrosine phosphorylation analysis for the tumor research and clinical diagnosis.

(Arg)9-SH2 superbinder: a novel promising anticancer therapy to melanoma by blocking phosphotyrosine signaling.

BACKGROUND: Melanoma is a malignant tumor with high misdiagnosis rate and poor prognosis. The bio-targeted therapy is a prevailing method in the treatment of melanoma; however, the accompanying drug resistance is inevitable. SH2 superbinder, a triple-mutant of the Src Homology 2 (SH2) domain, shows potent antitumor ability by replacing natural SH2-containing proteins and blocking multiple pY-based signaling pathways. Polyarginine (Arg)9, a powerful vector for intracellular delivery of large molecules, could transport therapeutic agents across cell membrane. The purpose of this study is to construct (Arg)9-SH2 superbinder and investigate its effects on melanoma cells, expecting to provide potential new approaches for anti-cancer therapy and overcoming the unavoidable drug resistance of single-targeted antitumor agents. METHODS: (Arg)9 and SH2 superbinder were fused to form (Arg)9-SH2 superbinder via genetic engineering. Pull down assay was performed to identify that (Arg)9-SH2 superbinder could capture a wide variety of pY proteins. Immunofluorescence was used to detect the efficiency of (Arg)9-SH2 superbinder entering cells. The proliferation ability was assessed by MTT and colony formation assay. In addition, wound healing and transwell assay were performed to evaluate migration of B16F10, A375 and A375/DDP cells. Moreover, apoptosis caused by (Arg)9-SH2 superbinder was analyzed by flow cytometry-based Annexin V/PI. Furthermore, western blot revealed that (Arg)9-SH2 superbinder influenced some pY-related signaling pathways. Finally, B16F10 xenograft model was established to confirm whether (Arg)9-SH2 superbinder could restrain the growth of tumor. RESULTS: Our data showed that (Arg)9-SH2 superbinder had the ability to enter melanoma cells effectively and displayed strong affinities for various pY proteins. Furthermore, (Arg)9-SH2 superbinder could repress proliferation, migration and induce apoptosis of melanoma cells by regulating PI3K/AKT, MAPK/ERK and JAK/STAT signaling pathways. Importantly, (Arg)9-SH2 superbinder could significantly inhibit the growth of tumor in mice. CONCLUSIONS: (Arg)9-SH2 superbinder exhibited high affinities for pY proteins, which showed effective anticancer ability by replacing SH2-containing proteins and blocking diverse pY-based pathways. The remarkable ability of (Arg)9-SH2 superbinder to inhibit cancer cell proliferation and tumor growth might open the door to explore the SH2 superbinder as a therapeutic agent for cancer treatment.

Thymic homing of activated CD4+ T cells induces degeneration of the thymic epithelium through excessive RANK signaling.

Activated T cells have been shown to be able to recirculate into the thymus from the periphery. The present study was aimed to elucidate the functional consequences of thymic homing of activated T cells upon developing thymocytes and thymic epithelial cells (TEC). In the presence of activated T cells, especially CD4+ T cells, T cell development was found to be inhibited in thymic organ cultures with markedly reduced cellularity. Thymic transplantation demonstrated that the inhibitory effect was most likely due to a defective microenvironment. As the major component of the thymic stroma, the TEC compartment was severely disturbed after prolonged exposure to the activated T cells. In addition to reduced cell proliferation, TEC differentiation was heavily skewed to the mTEC lineage. Furthermore, we demonstrated that RANKL highly expressed by activated CD4+ T cells was primarily responsible for the detrimental effects. Presumably, excessive RANK signaling drove overproduction of mTECs and possibly exhaustion of epithelial progenitors, thereby facilitating the deterioration of the epithelial structures. These findings not only reveal a novel activity of activated T cells re-entering the thymus, but also provide a new perspective for understanding the mechanism underlying thymic involution.

[Role of Rheb in Human Acute Myeloid Leukemia].

OBJECTIVE: To investigate the role of Rheb (mTOR activator) in AML development by measuring Rheb expression in bone marrow of adult AML patients and in AML cell line HL-60. METHODS: Real-time PCR assay was used to measure the Rheb mRNA expression in 27 AML patients and 29 ITP patients as control. The relationship between Rheb mRNA expression and age, AML subtype, fusion gene, splenomegaly, hepatomegaly and survival of AML patients was analyzed and compared. In addition, HL-60 cell line over-expressing Rheb was established, and the HL-60 cells and HL-60 cells with overexpression of Rheb were treated with Ara-C of different concentrations, the proliferation level was detected by CCK-8 method, and the IC50 was calculated. RESULTS: The mRNA level of Rheb in AML patients was similar to that in ITP patients (control). Interestingly, higher expression of Rheb was associated with better survival and was sensitive to Ara-C treatment. However, the expression level of Rheb was not associated with age, AML subtype, fusion gene, and hepatomegaly of patients. Lower expression level of Rheb was associated with splenomegaly. In vitro analysis of HL-60 line indicated that overexpression of Rheb could increased the cell sensitivity to Ara-C treatment (IC50=0.54 µmol/L) and caused HL-60 cell apoptosis. CONCLUSION: The lower Rheb expression is a poor prognostic indicator for AML patients, which is associated with AML splenomegaly, the patients and HL-60 cells with low expression of Rheb are insensitive to Ara-C treatment.

[Effect of TEB-415, a Derivative of Imatinib, on Multiple Myeloma].

OBJECTIVE: To investigate the growth inhibitory effect of Imatinib derivative TEB-415 on various multiple myeloma (MM) cell lines, such as U226, H929, RPMI8226, MM1R and MM1S. METHODS: TEB-415, a derivative of Imatinib was synthesized by modifying the chemical structure of Imatinib. MM cell lines (U226, H929, RPMI8226, MM1R and MM1S) were treated with TEB-415, Imatini and Bortezomib of various concentrations. Cells were grown for 72 hours and the growth rate was measured by CCK-8 method, cell morphology was observed and the IC50 was calculated. RESULTS: TEB-415 could inhibit H929 and RPMI8226 growth significantly. When the concentration of TEB-415 was <0.1 nmol/L, >50% H929 cells died. The IC50 of Imatinib was 0.123 mol/L while the IC50 of Bortezomib was 0.03 nmol/L. In RPMI8226 cell line, when the concentration of TEB-415 was 11.9 mol/L, more than 50% of cells died. In contrast, when RPMI8266 were treated with Imatinib of the concentration of 12.8 mol/L, cells grew normally. CONCLUSION: In comparison to Imatinib, TEB-415, a derivative of Imatinib, can kill H929 MM cells much effectively, its effecacy is only inferior to Bortezomib. RPMI8226, an MM cell line is insensitive to Imatinib, but still sensitive to TEB-415 and its growth can be inhibited by TEB-415.

[Applications of Microscopic Imaging and Analysis Technology in Studies of Neutrophil Movement and Phagocytosis].

OBJECTIVE: To analyze and evaluate the application of spinning disk confocal microscopy and imaging analysis software in movement and phagocytosis of neutrophils. METHODS: Neutrophils were isolated from bone marrow by centrifugation on discontinuous Percoll gradient, and then were stained with PE Gr-1 antibody and mixed with FITC-labeled Zymosan A bioparticles. Multichannel time-lapse videos were captured by using the spinning disk confocal microscopy. The result was analyzed by using volocity and ImageJ software, the parameters associated with movement and phagocytosis of neutrophils were analyzed, including morphological changes, cell tracking, pseudopod dynamics, binding and phagocytosis index. RESULTS: Most neutrophils would be polarized in response to Zymosan particles during a short time. Binding and phagocytosis process occured in forty minutes. CONCLUSION: A method of precisely quantifying the movement and phagocytosis of neutrophils using microscopic imaging and imaging analysis technique has been set up successfully. Using this method, biological activity and function of neutrophils can be evaluated visually and rapidly. The physiologically rapid response to Zymosan particles can be applied to the neutrophils function research in the future.

[The rheology properties of common hydrophilic gel excipients].

To investigate theological properties of common hydrophilic gel excipients such as Carbopol based on viscosity, the viscosity was determined by rotation method and falling-ball method. Linear regression was made between ln(eta) and concentration, the slope of which was used to explore the relation between viscosity and concentration of different excipients. The viscosity flow active energy (E(eta)) was calculated according to Arrhenius equation and was used to investigate the relation between viscosity and temperature of different excipients. The results showed that viscosities measured by two methods were consistent. Concentration of guargum (GG) and hydroxypropylmethyl cellulose (HPMC) solution had a great influence on the viscosity, k > 5; while concentration of polyvinylpyrrolidone-K30 (PVP-K30) and polyethylene glycol 6000 (PEG6000) exerted a less effect on viscosity, k < 0.2; viscosity flow active energy of different excipients were close, which ranged from 30 to 40 kJ x mol(-1). Therefore, theological properties study could provide the basis for application of excipients and establish a foundation for the research of relation between excipients structure, property and function.

[Effects of Rheb overexpression in HL-60 and K562 leukemia cell lines].

mTOR (mammalian target of rapamycin) is the center for cellular activities. It controls many cell activities via inhibiting apoptosis and promoting cell growth. Rheb can activate mTOR signaling pathway and participate in genesis and development of multiple cancers. This study was purposed to explore the underlying role of Rheb in human myeloid leukemia by using the myeloid leukemia cell lines. Two myeloid leukemia cell lines HL-60 and K562 overexpressing Rheb were established with retrovirus containing Rheb. The mRNA and protein expressions of Rheb were determined by Real-Time PCR and Western blot respectively. Cell proliferation rate was examined by CCK-8 assay and apoptosis rate was analyzed using Annexin V and 7-AAD double-staining. The results showed that Rheb was overexpressed in both HL-60 and K562 cell lines. The Rheb overexpression cell lines were successfully established. It is found that overexpression of Rheb could promote cell growth. Furthermore, the overexpression of Rheb could accelerate cells entering into G2/M phase (P < 0.01), while did not affect the apoptosis. It is concluded that Rheb overexpression promotes myeloid leukemia cell proliferation through accelerating cell cycle progression.