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Background Heart failure with preserved ejection fraction (HFpEF) accounts for 50% of patients with heart failure. Clinically, HFpEF prevalence shows age and gender biases. Although the majority of patients with HFpEF are elderly, there is an emergence of young patients with HFpEF. A better understanding of the underlying pathogenic mechanism is urgently needed. Here, we aimed to determine the role of aging in the pathogenesis of HFpEF. Methods and Results HFpEF dietary regimen (high‐fat diet + Nω‐Nitro‐L‐arginine methyl ester hydrochloride) was used to induce HFpEF in wild type and telomerase RNA knockout mice (second‐generation and third‐generation telomerase RNA component knockout), an aging murine model. First, both male and female animals develop HFpEF equally. Second, cardiac wall thickening preceded diastolic dysfunction in all HFpEF animals. Third, accelerated HFpEF onset was observed in second‐generation telomerase RNA component knockout (at 6 weeks) and third‐generation telomerase RNA component knockout (at 4 weeks) compared with wild type (8 weeks). Fourth, we demonstrate that mitochondrial respiration transitioned from compensatory state (normal basal yet loss of maximal respiratory capacity) to dysfunction (loss of both basal and maximal respiratory capacity) in a p53 dosage dependent manner. Last, using myocardial‐specific p53 knockout animals, we demonstrate that loss of p53 activation delays the development of HFpEF. Conclusions Here we demonstrate that p53 activation plays a role in the pathogenesis of HFpEF. We show that short telomere animals exhibit a basal level of p53 activation, mitochondria upregulate mtDNA encoded genes as a mean to compensate for blocked mitochondrial biogenesis, and loss of myocardial p53 delays HFpEF onset in high fat diet + Nω‐Nitro‐L‐arginine methyl ester hydrochloride challenged murine model.

Myocardium ischemia-reperfusion injury (IRI) is the major cause of postoperative cardiac dysfunction. While intrathecal morphine preconditioning (ITMP) can reduce IRI in animals, the molecular processes underlying IRI and ITMP remain elusive. Transient receptor potential vanilloid type 1 (TRPV1) is highly expressed in cardiac sensory neurons and has a crucial role in detecting myocardial ischemia. This study aimed to determine the role of up-regulated dorsal root ganglion (DRG)-TRPV1 in IRI and whether its inhibition contributes to ITMP-induced cardioprotection. Animal model of IRI was established by left coronary artery occlusion (30 min) and reperfusion (2 h) in rats. Intrathecal intubation was prepared for morphine preconditioning, TRPV1-shRNA or selective TRPV1 antagonist administration. After IRI, both protein and phosphorylation levels of TRPV1 were significantly increased, and the immunofluorescence intensity of TRPV1 was increased and colocalized with μ-opioid receptors in DRG. Intrathecal pre-administration of either TRPV1-shRNA or TRPV1 antagonist significantly reduced myocardial injury and the upregulation of TRPV1 in DRG induced by IRI. Simultaneously, ITMP significantly suppressed TRPV1 protein expression and phosphorylation in DRG, as well as the heart infarct size and arrhythmia score caused by IRI. The suppression of TRPV1 elevation and activation by ITMP were reversed by intrathecal injection of the selective μ receptor antagonist. Furthermore, IRI elevated DRG cAMP, while intrathecal administration of the selective cAMP-PKA inhibitor reduced myocardial injury. Finally, we showed that activation of opioid receptor by morphine inhibited PKA activator-induced TRPV1 channel activity at the cellular level. These findings suggest that the elevation and activation of TRPV1 in DRG during myocardial ischemia-reperfusion might be responsible for cardiac injury. ITMP exerts cardioprotection by inhibiting DRG-TRPV1 activity via modulation cAMP. Therefore, inhibition of TRPV1 upregulation in DRG might be used as a novel therapeutic mechanism for myocardium ischemia-reperfusion injury.

HIV subtypes convey important epidemiological information and possibly influence the rate of disease progression. In this study, HIV disease progression in patients infected with CRF01_AE, CRF07_BC, and subtype B was compared in the largest HIV molecular epidemiology study ever done in China. A national data set of HIV pol sequences was assembled by pooling sequences from public databases and the Beijing HIV laboratory network. Logistic regression was used to assess factors associated with the risk of AIDS at diagnosis ([AIDSAD], defined as a CD4 count

Background Myocardial ischemia and reperfusion-evoked spinal reflexes involve nociceptive signals that trigger neuronal excitation through cardiac afferents, projecting into the thoracic spinal cord. Ischemic preconditioning (IPC) involves brief episodes of sublethal ischemia and reperfusion enhances the resistance of the myocardium to subsequent ischemic insults. This study investigated the effects of IPC on ischemia-reperfusion (I/R) stimulation-induced activation in the thoracic spinal cord of rats. Methods A new remotely controlled I/R model was established. The infarct size was determined as a percentage of area at risk (IS/AAR) and arrhythmia scores were evaluated. Non-invasive in vivo fMRI was used for signal quantitative analysis of thoracic spinal spatiotemporal. The role of IPC on the excitability of substantia gelatinosa (SG) neurons was assessed by spinal patch clamp recording technique. The altered expressions of c-Fos, SP, and CGRP in T4 segment were detected by immunohistochemical staining. Results The novel I/R model was induced successfully and reliably utilized, and IPC treatment markedly reduced the myocardial infarct size. fMRI analysis revealed that IPC reduced the increased BOLD signals induced by prolonged ischemia-reperfusion. Patch clamp recording showed that IPC treatment reversed the enhanced excitability of SG neurons during I/R treatment. The results of immunofluorescent staining indicated that IPC mitigated the I/R-induced dramatic increase of c-Fos, and reduced the release of SP and CGRP in dorsal horns of spinal cord. Conclusions These results suggested that IPC suppressed neuronal activation induced by I/R stimuli in rat thoracic spinal cord using spinal cord fMRI and patch clamp recording techniques.

HIV-1 CRF01_AE and CRF07_BC have been two mainly circulating HIV-1 strains in the men who have sex with men (MSM) population in Beijing for years. These two subtypes together were accounting for 78.1% of HIV-1 positive cases newly diagnosed in Beijing, 2016. In this study, we report a novel CRF01_AE/CRF07_BC second-generation unique recombinant form (URF) (named DT1427_NFLG) of HIV-1 identified in MSM population. The near full-length genome of DT1427_NFLG is about 8.8 kb with four CRF07_BC fragments inserted into the CRF01_AE backbone. In China, several novel second-generation URFs were reported in recent years and Beijing, as the capital of China, attracting a huge number of people all over the country to work and live, is confronted with the risk of the epidemic of recombinant HIV-1 strains. Therefore, it is necessary to take measures to monitor the emergency of novel recombinant of HIV-1.

When viewing dichoptic stimuli in long time duration, visual percepts are always the alternation between the left and right eye inputs, while not the combination. This is known as binocular rivalry. An efficient coding theory reported that binocular visual inputs can be combined into binocular summation (S+) and difference (S−) channels in V1 brain area. In this study, we used specially designed stimuli as the previous study, in which monocular inputs caused ambiguous percepts, but S+ and S− channels had unambiguous percepts. We aim to investigate whether the visual percepts alter between S+ and S− channels in long time duration and whether vergence eye movements are involved in the process. To do so, the stimuli were presented in 300-s time duration in a trial, and a binocular eye tracker was used to record eye information. Participants’ real-time behavioral responses about the visual percepts and binocular information were recorded simultaneously. The results show there are perceptual flips between S+ and S− channels in both central and long time viewing conditions. More importantly, in central vision there are vergence eye movements before perceptual flips, suggesting the involvement of high level visual attention; the time of a perceptual flip from S+ is shorter than that of a flip from S−, which might be due to different involvements of visual attention, indicating a bias of feedback connection from higher brain areas for visual attention to S+ channel. Since S+ and S− dominated signals can be carried by different types of binocular neurons, our results provide new insights into high level visual attention and binocular neurons in V1 brain area by using specially designed dichoptic stimuli and eye vergence as measuring tools.

The therapeutic effects of mitochondria-targeted antioxidants have been demonstrated in many pathological conditions, but their effect on neuropathic pain remains unclear. The objective was to study the therapeutic effects and mechanisms of mito-TEMPO (MT), as a nitroxide conjugated with a triphenylphosphonium moiety, on neuropathic pain in rats. Rats were randomly assigned to sham control (sham), chronic constrictive injury (CCI) or MT treatment groups (sham+MT and CCI+MT). All animals received CCI of the left sciatic nerve except those in the sham group. Overall, 0.7 mg/kg of MT was intraperitoneally injected once daily for 14 consecutive days starting from day 7 after surgery. Mechanical paw withdrawal threshold and thermal paw withdrawal latency were detected to assess pain behavior. Malondialdehyde and reduced glutathione content and total superoxide dismutase activity of serum and spinal cord tissues were estimated to assess oxidative stress levels. Mitochondrial morphology and dynamin-related proteins were used to evaluate mitochondrial function, such as fusion [Mitofusin (Mfn) and optic atrophy 1 gene protein (OPA1)] and fission [dynamin-related protein (DRP1) and Fis1]. Paw withdrawal threshold and thermal paw withdrawal latency were significantly increased in the CCI+MT group compared with the CCI group. The malondialdehyde content was decreased whereas glutathione content and superoxide dismutase activity were increased in the serum of CCI+MT rats. Furthermore, MT substantially attenuated the elevated number and decreased size of mitochondria induced by CCI. Finally, MT significantly increased expressions of Mfn1 and OPA1 and significantly decreased expression of DRP1 and Fis1. The mitochondria-targeted antioxidant MT relieved neuropathic pain induced by CCI by protecting mitochondria against oxidative stress injury.

Exosomes secreted from cancer cells promote tumor progression through the transfection of containing microRNA (miRNA), mRNAs and proteins. Yet, little of this knowledge has translated into the therapeutic application. Herein, we propose a tumor therapeutic strategy via decreasing exosomal miRNA secretion. The study designed small interfering RNA (siRNA) loaded nanoparticles to downregulate sphingosine kinase 2 (Sphk2) and investigate their potential in decreasing exosomal oncogenic miRNA content and inhibiting tumor growth. The synthesized lipid (2E)-4-(dioleostearin)-amino-4‑carbonyl-2-butenoic (DC) and chitosan were utilized to produce siRNA loaded nanoparticles (DC/CS-siRNA NPs), with optimal siRNA complexation and high transfection efficacy. We demonstrated that Sphk2 gene silencing induced by nanoparticles in hepatocellular carcinoma (HCC) cells could reduce miRNA-21 sorting into exosomes, contributing to the inhibition of tumor cell migration and tumorigenic function of exosomes to normal liver cells. Furthermore, in xenograft mouse model, Sphk2 siRNA loaded DC/CS NPs could significantly block tumor progression of malignancy HCC. These results suggest a new therapeutic approach for tumor treatment by ablating oncogenic miRNA in malicious exosomes.

Background The therapeutic potential of cardiac μ-opioid receptors in ischaemia-reperfusion (I/R) injury during opioid-modulating diseases, such as heart failure, is unknown. We aimed to explore the changes of cardiac μ-opioid receptor expression during heart failure, and its role in opioid-induced cardioprotection. Methods Rats received doxorubicin (DOX) or were subjected to coronary artery ligation to induce heart failure, or received normal saline (NS) as control. Hearts from NS or DOX rats were isolated and subjected to myocardial ischaemia and reperfusion in an in vitro perfusion system. The opioid [D-Ala,2 N-MePhe,4 Gly-ol]-enkephalin (DAMGO), with a high μ-opioid receptor specificity, morphine, and remifentanil were administrated before I/R with or without opioid receptor antagonists, or an extracellular signal-regulated kinase (ERK) inhibitor. Results Cardiac μ-opioid receptor mRNA concentrations were 3.2 times elevated in DOX-treated rats compared with NS rats, while cardiac μ-opioid receptor protein concentrations showed 6.1- and 3.5-fold increases in DOX-treated and post-infarcted rats, respectively. DAMGO reduced I/R-caused infarct size, expressed as the ratio of area at risk, from 0.50 (0.04) to 0.25 (0.03) in failing rat hearts, but had no effect on infarct size in control hearts. DAMGO promoted phosphorylation of ERK and glycogen synthase kinase (GSK)-3β only in failing hearts. DAMGO-mediated cardioprotection was blocked by an ERK inhibitor. The μ-opioid receptor antagonist D-Pen-Cys-Tyr-D-Trp-Orn-Thr-Pen-Thr-NH2 (CTOP) prevented morphine- and remifentanil-induced cardioprotection and phosphorylation of ERK and GSK-3β in failing hearts. In contrast, δ- and κ-opioid receptor selective antagonists were less potent than CTOP in the failing hearts. Conclusions Cardiac μ-opioid receptors were substantially up-regulated during heart failure, which increased DAMGO-induced cardioprotection against I/R injury.

There are two windows of protection for remote ischemic preconditioning (RIPC), an early (ERIPC) and a late-phase (LRIPC). While ERIPC has been well studied, works on LRIPC are relatively scarce, especially for the kidneys. We aimed to compare the effects of early-phase versus late-phase RIPC in patients with laparoscopic partial nephrectomy (LPN).A randomized controlled study SETTING: The Second Affiliated Hospital of Anhui Medical University, 1 May 2012 to 30 October 2013 PATIENTS: Sixty-five ASA 1 to 2 patients scheduled for LPN were located randomly to ERIPC group, LRIPC group and CON group (control).Three five-minute cycles of right upper limb ischaemia and reperfusion were performed after induction of anesthesia in ERIPC group. Patients in LRIPC group received similar treatment 24h before surgery, while control patients were not subjected to preconditioning.Serum neutrophil gelatinase-associated lipocalin (NGAL) and serum cystatin C (CysC) were evaluated before the induction of anesthesia (0h), 2h (2h) and 6h (6h) after surgery. Unilateral glomerular filtration rates (GFR) were assessed before and after surgery to evaluate overall renal function.Serum NGAL and CysC were significantly lower in ERIPC and LRIPC groups at 2h post-operation (P0.001), 6h post-operation (P0.001). Additionally, The GFR were significantly lower in ERIPC and LRIPC groups than in CON group at the 3rd month after surgery (P=0.019; P0.001). Moreover, compared to the ERIPC group, concentration of NGAL and CysC in LRIPC group decreased to a greater extent, while GFR and the percentage of decrement was significantly less in the LRIPC group (P=0.016; P0.001).Regardless of early-phase or late-phase intervention, limb remote ischemic preconditioning confers protection on renal ischemia-reperfusion injury in patients with laparoscopic partial nephrectomy, and the late-phase protection is more prominent.

The objective of this study was to monitor the trend of addiction drug use and its relationship with sexually transmitted infections (STIs) among female drug users (FDUs). Serial cross-sectional surveys were conducted during 2010–2014 among FDUs in Beijing to collect information on addiction drug usage, sexual behaviors, and STI prevalence. Characteristics were analyzed and compared between traditional and synthetic drug users among FDUs by logistic regression method. A total of 3859 FDUs were surveyed during 2010–2014, with the median age being 32.7 years old. The proportion of synthetic drug users among FDUs increased from 43.7% in 2010 to 70.7% in 2014. Compared with traditional drug users, synthetic drug users were younger (P

Remifentanil preconditioning has been demonstrated to reduce myocardial ischemia reperfusion injury in rat hearts, while the mechanisms are not fully understood. This study investigated the protective effects of remifentanil against hypoxia-reoxygenation injury in adult rat cardiomyocytes and the mechanisms involving opioid receptors and downstream phosphatidylinositol-3-kinase/protein kinase B (PI3K/Akt) and extracellular signal-regulated kinase (ERK) signaling pathways. Adult rat cardiomyocytes were pretreated with remifentanil at different concentrations and then subjected to 90min hypoxia followed by 120min reoxygenation. The δ- (naltrindole), κ- (nor-binaltorphimine), or μ-opioid receptor antagonist (CTOP), as well as ERK inhibitor (PD98059) or PI3K inhibitor (wortmannin) was added before remifentanil preconditioning, respectively. Remifentanil showed significant protective effects against hypoxia-reoxygenation injury by increasing cell survival (Trypan blue staining) while reducing LDH activity and cell apoptosis (Hoechst staining). These effects were markedly reversed by naltrindole and were partially blocked by nor-binaltorphimine. Pretreatment of either PD98059 or wortmannin also abolished the protective effects of remifentanil. Following remifentanil preconditioning, the phosphorylation level of Akt reached peak at 10min of reoxygenation. ERK phosphorylation, however, was subsequently enhanced at 120min of reoxygenation. The phosphorylation levels of Akt and ERK were both blocked by naltrindole, but not nor-binaltorphimine or CTOP. Wortmannin inhibited the phosphorylation of both Akt and ERK, whereas PD98059 suppressed the phosphorylation of ERK only. In conclusion, our results suggested that remifentanil protected adult rat cardiomyocytes from hypoxia-reoxygenation injury and its effects appears to be dependent on the δ-opioid receptor mediated activation of PI3K/Akt and subsequent ERK signaling pathways.

Background MicroRNAs (miRNAs) have been implicated in ischemia-reperfusion injury and ischemic preconditioning. Opioid pre- and postconditioning have powerful protective effects on the heart, but it is still not known whether miRNAs are involved in opioid-induced cardioprotection. The present study was designed to investigate the role of miRNAs in morphine preconditioning (MPC)-induced cardioprotection. Methods MiRNA microarray analysis was performed to examine the differentially expressed miRNAs caused by MPC in adult rat cardiomyocytes. A dual-luciferase reporter assay was performed to confirm the direct regulation of miR-133b-5p on the target gene Fas . MiR-133b-5p mimic or inhibitor was separately transfected into myocardial H9c2 cells to examine the role of miR-133b-5p in morphine-induced cardioprotection. Results MPC protected adult rat cardiomyocytes against hypoxia/reoxygenation (H/R) injury by reducing cell injury and death. MiRNA microarray data showed that a total of 39 miRNAs were differentially expressed after MPC treatment. A Dual-luciferase reporter assay confirmed that miR-133b-5p directly targets the Fas gene. After H/R injury, the decrease in miR-133b-5p and a contemporaneous rise in Fas mRNA and protein levels in adult rat cardiomyocytes were prevented by MPC treatment. In H9c2 cardiomyocytes, overexpression of miR-133b-5p reduced H/R-induced cell injury and apoptosis by inhibiting Fas expression. Knockdown of miR-133b-5p blocked morphine-mediated cardioprotection by reducing miR-133b-5p levels while enhancing the expression of Fas mRNA and protein. Conclusions MPC causes a change in miRNA expression in rat cardiomyocytes. Morphine may protect cardiomyocytes against H/R injury through upregulation of miR-133b-5p by targeting Fas .

Morphine has been widely used as rescue treatment for heart attack and failure in humans for many decades. Relatively little has been known about the role of spinal opioid receptors in morphine cardioprotection. Recent studies have shown that intrathecal injection of morphine can reduce the heart injury caused by ischemia (I)/reperfusion (R) in rats. However, the molecular and cellular mechanisms underlying intrathecal morphine cardioprotection has not been determined. Here, we report that intrathecal morphine postconditioning (IMPOC) rescued mean artery pressure (MAP) and reduced myocardial injury in I/R. Pretreatment with either naloxone (NAL), a selective mu-opioid receptor antagonist, or nitric oxide synthase (NOS) inhibitors via intrathecal delivery completely abolished IMPOC cardioprotection, suggesting that the spinal mu-opioid receptor and its downstream NOS signaling pathway are involved in the mechanism of the morphine-induced effect. Consistent with this, IMPOC significantly enhanced spinal neural NOS phosphorylation, nitric oxide, and cGMP content in a similar time course. Intrathecal application of 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one, a specific inhibitor of guanylate cyclase, completely ablated IMPOC-induced enhancement of cardioprotection and spinal cGMP content. IMPOC rescue of MAP and ischemic injury is correlated with IMPOC enhancement of NOS signaling. Collectively, these findings strengthen the concept of spinal mu-opioid receptors as a therapeutic target that mediates morphine-induced cardioprotection. We also provide evidence suggesting that the activation of spinal NOS signaling is essential for morphine cardioprotection.

Evidences from previous studies confirmed that intrathecal morphine preconditioning (ITMP) reduces the cardiac injury of ischemia-reperfusion (IR) via the central nervous system. However, the molecular mechanism is not fully understood. The breath of central nerve growth factor (NGF) during nociceptive transmission has been well documented, and little is known about the significance of NGF in myocardial injury of IR and intrathecal morphine-induced cardioprotection. To address these questions, we over-expressed or silenced NGF in the spinal cord by using intrathecal injection of lentivirus-NGF or shRNA respectively, accompanied by ITMP in the IR rat model. The levels of NGF and tropomyosin receptor kinase A (Trka) as well as transient receptor potential vanilloid 1 (TRPV1) in the T2-6 spinal cord were evaluated. The results showed that cardiac damage indicators induced by IR, including the increased infarct size, arrhythmia score and serum troponin levels were attenuated after ITMP. However, overexpression of spinal NGF significantly reversed these decreases, as well as reduced the expression and phosphorylation of TRPV1 that was elicited by ITMP. Conversely, silencing of spinal NGF enhanced ITMP-induced cardioprotective effects. Phosphorylation and expression of TRPV1 in the spinal cord were significantly decreased after regional NGF silencing. These findings suggested that the cardioprotective effects of ITMP may implement by mediating through spinal NGF expression, wherein it involves the nociceptor TRPV1. NGF may act as a potential therapeutic target in the development of new agents for the treatment of cardiac injury induced by IR.

Oral absorption of protein/peptide-loaded nanoparticles is often limited by multiple barriers of the intestinal epithelium. In addition to mucus translocation and apical endocytosis, highly efficient transepithelial absorption of nanoparticles requires successful intracellular trafficking, especially to avoid lysosomal degradation, and basolateral release. Here, the functional material, deoxycholic acid-conjugated chitosan, is synthesized and loaded with the model protein drug insulin into deoxycholic acid-modified nanoparticles (DNPs). The DNPs designed in this study are demonstrated to overcome multiple barriers of the intestinal epithelium by exploiting the bile acid pathway. In Caco-2 cell monolayers, DNPs are internalized via apical sodium-dependent bile acid transporter (ASBT)-mediated endocytosis. Interestingly, insulin degradation in the epithelium is significantly prevented due to endolysosomal escape of DNPs. Additionally, DNPs can interact with a cytosolic ileal bile acid-binding protein that facilitates the intracellular trafficking and basolateral release of insulin. In rats, intravital two-photon microscopy also reveals that the transport of DNPs into the intestinal villi is mediated by ASBT. Further pharmacokinetic studies disclose an oral bioavailability of 15.9% in type I diabetic rats after loading freeze-dried DNPs into enteric-coated capsules. Thus, deoxycholic acid-modified chitosan nanoparticles can overcome multiple barriers of the intestinal epithelium for oral delivery of insulin.

Ethnopharmacological relevance Astragalus membranaceus and Salvia miltiorrhiza have been used for centuries in China to treat liver diseases. Previous studies have shown that these herbs and their extracts inhibit the development of liver fibrosis and the proliferation and invasion of human hepatoma HepG2 cells. Further study of their pharmacological effects on hepatocellular carcinoma (HCC) is needed. To investigate the effects of Compound Astragalus and Salvia miltiorrhiza Extract (CASE) on diethylinitrosamine (DEN)-induced hepatocarcinogenesis in rats. Materials and methods Male rats were divided into five groups, with the first group serving as normal control, the second group receiving 0.2% DEN solution five times a week for 14 weeks, and the third to fifth group receiving the same DEN as in the second group together with CASE at the doses of 60, 120, and 240 mg/kg per day for 16 weeks, respectively. Hepatoma incidence, serum enzymes levels, degree of fibrosis and hydroxyproline content were evaluated and compared across the five groups to determine CASE's suppression of fibrosis and HCC progression. In addition, an in vitro experiment using HepG2 cells was conduct to verify CASE's effect on the transcription of plasminogen activator inhibitor-1 (PAI-1) mRNA. Results CASE treatment significantly reduced the incidence and multiplicity of DEN-induced HCC development in a dose-dependent manner. It significantly suppressed the elevation of alanine transaminase, aspartate aminotransferase, gamma-glutamyl transferase, alkaline phosphatase, hyaluronic acid, direct bilirubin and total bilirubin, and significantly lessened the depression of serum total protein in DEN-induced HCC rats. CASE treatment also significantly suppressed the elevated expression of GST-P and α-SMA. The in vitro experiment confirmed that CASE inhibits the transcription of PAI-1 mRNA in HepG2 cells induced by TGF-β 1 in a dose-dependent manner. Conclusions CASE suppresses DEN-induced hepatocarcinogenesis by inhibiting fibrosis and PAI-1 mRNA transcription, suggesting its potential clinical application in preventing and treating human HCC.

Aims Ischemia reperfusion (I/R) injury is an inevitable event arising during the cardiovascular diseases development and the process of potent surgical treatments. microRNAs (miRNAs) are critical regulators of multiple cell processes including I/R injury. The present study aims to quantify miRNA alterations and regulated genes upon hypoxia-reoxygenation (H/R) injury in a rat heart failure model comparing with normal cardiomyocytes. Main methods Chronic heart failure was established by injecting doxorubicin (2 mg/kg/week) for 6 weeks, then H/R was performed on primary cultured cardiomyocytes isolated from normal and failed heart. Cellular injury was evaluated by detecting LDH release levels, cell variability and apoptotic rate. Dysregulated miRNAs in control, hypoxia preconditioning (HPC) and morphine preconditioning (MPC) groups under two conditions were quantified by microarray analysis. Fas protein expression was analyzed using Western Blotting analysis. Key findings Chronic heart failure was confirmed with lower ejection fraction (EF), and significant cellular injury. HPC could reverse the injury induced by H/R in normal heart rather than failed heart, otherwise, MPC significantly attenuated cellular injury dose dependently in both conditions. There was 12 miRNAs significantly altered after doxorubicin injection, 7 downregulated and 5 upregulated. miR-133b-5p, miR-6216, miR-664-1-5p and let7e-5p were differentially expressed after HPC and MPC treatments. The direct interaction between miR-133b-5p and target gene Fas were established. The Fas protein expression was manipulated by MPC not HPC affording protective effect against H/R injury. Significance We investigated that miR-133b-5p might play a particularly important role in the cardioprotective effect of MPC by regulating the target gene Fas.

Epidural anesthesia may attenuate the sympathetic hyperactivity and stress response from surgery. In this study, we compared the stress response, hemodynamic variables, and recovery profiles of patients undergoing total IV anesthesia (TIVA) and intraoperative dexmedetomidine with those receiving epidural anesthesia and TIVA.Ninety patients undergoing elective open gastrectomy under TIVA were recruited. The dexmedetomidine group (group D, n = 30) received IV dexmedetomidine 0.6 μg/kg before the induction of general anesthesia, followed by dexmedetomidine 0.4 μg/kg/h until peritoneal closure. The control group (group C, n = 30) received volume-matched normal saline infusion as placebo. The epidural group (group E, n = 30) received epidural anesthesia with 0.375% ropivacaine combined with TIVA. The hemodynamic variables and recovery characteristics during emergence were evaluated. Blood samples for norepinephrine (NE), epinephrine (E), cortisol (Cor), and cytokines (tumor necrosis factor-α [TNF-α], interleukin [IL]-6, and IL-10) were obtained before the administration of dexmedetomidine or epidural anesthesia (baseline), immediately after tracheal intubation, upon incision, at the time of celiac exploration, and at tracheal extubation.Compared with group E, there were no differences in the plasma concentration levels of NE, E, Cor, and cytokines (TNF-α, IL-6, and IL-10) in group D at all time points. The levels of NE and E in groups D and E were significantly lower than that in group C, at all time points following induction (all P0.0001 except at incision which were P = 0.001 and P = 0.004), and the level of Cor in groups D and E was significantly lower than that in group C at celiac exploration (P = 0.017 and P = 0.019) and immediately after tracheal extubation (P0.0001). The levels of TNF-α, IL-6, and IL-10 increased after the celiac exploration in the 3 groups. The levels of plasma TNF-α, IL-6, and IL-6/IL-10 ratio were higher in group C than in groups D and E at celiac exploration and tracheal extubation (all P0.0001 except at celiac exploration which were P = 0.005 and P =0.038 for TNF-α and P = 0.049 and P = 0.038 for IL-6/IL-10 ratio). In group D, the heart rate was significantly slower after commencing dexmedetomidine and remained significantly slower throughout the operative course (all P0.0001 except at tracheal extubation which was P = 0.032). The number of patients who required intervention because of intraoperative hypotension was significantly higher in group E (36.7%) compared with groups D and C (13.3% and 10.0%) (P = 0.037, P = 0.015). The times to eye opening and tracheal extubation were similar in all groups. There were fewer incidences of agitation in group D (6.7 %) than in group C (26.6%) (P = 0.038).When used in conjunction with TIVA, intraoperative dexmedetomidine blunts surgical stress responses to an extent comparable to combined epidural and general anesthesia without compromising hemodynamic stability and with minimal adverse effects during the intraoperative period.

Preconditioning against myocardial ischemia-reperfusion (I/R) injury can be suppressed in some pathological conditions. This study was designed to investigate whether morphine preconditioning (MPC) exerts cardioprotection in doxorubicin (DOX)-induced heart failure in rats and the mechanisms involved. Phosphatidylinositol-3 kinase/protein kinase B (PI3K/Akt), extracellular signal-regulated kinase (ERK) and glycogen synthase kinase (GSK)-3β pathways were examined. Normal and DOX-induced failing rat hearts were subjected to I/R injury using a Langendorff perfusion system with or without MPC or ischemic preconditioning (IPC). The PI3K inhibitor (wortmannin) or ERK inhibitor (PD98059) was infused before MPC. In normal hearts, both MPC and IPC significantly reduced infarct size and the rise in lactate dehydrogenase (LDH) level caused by I/R injury. Pretreatment with wortmannin or PD98059 abrogated the protective effects of MPC and suppressed the phosphorylation of Akt, ERK and GSK-3β. In failing rat hearts, however, MPC retained its cardioprotection while IPC did not. This protective effect was abolished by PD98059 but not wortmannin. MPC increased the level of p-ERK rather than p-Akt. The phosphorylation of GSK-3β induced by MPC was reversed by PD98059 only. IPC did not elevate the expression of p-ERK, p-Akt and p-GSK-3β in failing rat hearts. We conclude that MPC is cardioprotective in rats with DOX-induced heart failure while IPC is not. The effect of MPC appears to be mediated via the ERK/GSK-3β pathway independent of PI3K/Akt.

Previous studies showed Compound Astragalus and Salvia miltiorrhiza extract (CASE), extract from Astragalus membranaceus and Salvia miltiorhiza, significantly suppresses hepatocellular carcinoma (HCC) in rats induced by diethylinitrosamine (DEN), and in vitro experiments further demonstrated that CASE's anti-HepG2 cell invasion is associated with transforming growth factor-β (TGF-β). We hypothesized that CASE's suppression of HCC is modulated by TGF-β/Smad signaling, and we conducted this in vivo study to test this hypothesis.Rats were divided into the normal control, the DEN group, and three CASE (60, 120, and 240 mg/kg) treatment groups. The expression of phosphorylation(p) Smad both at C-terminal and linker region, plasminogen activator inhibitor 1, and Smad4 and Smad7 of liver tissues were measured and compared across the five groups.The positive staining of pSmad2L and pSmad3L increased both in hepatoma nodule areas and adjacent relatively normal liver tissues in rats treated with DEN, while the positive staining of pSmad2C and pSmad3C increased only in relatively normal liver tissues adjacent to hepatoma tissues. The elevated expression of pSmad2C, pSmad2L, pSmad3L, Smad4, and plasminogen activator inhibitor 1 proteins were suppressed by CASE in a dose-dependent manner. CASE treatment also significantly reduced the intranuclear amounts of pSmad2L and pSmad3L, and upregulated the elevation of pSmad3C positive cells and protein expression in a dose-dependent manner.The results suggest that CASE significantly suppresses HCC progression by mediating TGF-β/Smad signaling, especially by modulating Smad3 phosphorylation both at the C-terminal and linker region.

Global cerebral ischemia followed by reperfusion, which leads to extensive neuronal damage, particularly the neurons in the hippocampal CA1 region. Apoptosis is one of the major mechanisms that lead to neuronal death after cerebral ischemia and reperfusion. The neuroprotective effects of remifentanil preconditioning against cerebral ischemia/reperfusion injury have been recently reported. Here we investigated whether remifentanil postconditioning exerts neuroprotective effects against global cerebral ischemia/reperfusion injury in rats and its potential mechanisms. Global cerebral ischemia was performed via 10 min of four-vessel occlusion. Terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling positive cells and expression of Bcl-2 and Bax in the hippocampal CA1 region were assessed after reperfusion. Morris water maze task was used to quantify spatial learning and memory deficits after reperfusion. We found remifentanil postconditioning markedly improved the spatial learning and memory as well as attenuated neuronal apoptosis in hippocampus caused by cerebral ischemia/reperfusion injury. In addition, remifentanil postconditioning enhanced the expression of anti-apoptotic gene Bcl-2 while suppressed the expression of pro-apoptotic gene Bax in hippocampal CA1 region. However, the neuroprotective effects of remifentanil postconditioning were abolished by pretreatment of the PI3K inhibitor LY294002. The results suggest that remifentanil postconditioning exhibits neuroprotective effects against global cerebral ischemia/reperfusion injury in rats, and its mechanisms might involve inhibition of neuronal apoptosis through the PI3K pathway.