Circuit-based neuromodulation enhances delayed recall in amnestic mild cognitive impairment.

BACKGROUND: This study aimed to investigate the efficacy of circuits-based paired associative stimulation (PAS) in adults with amnestic mild cognitive impairment (aMCI). METHODS: We conducted a parallel-group, randomised, controlled clinical trial. Initially, a cohort of healthy subjects was recruited to establish the cortical-hippocampal circuits by tracking white matter fibre connections using diffusion tensor imaging. Subsequently, patients diagnosed with aMCI, matched for age and education, were randomly allocated in a 1:1 ratio to undergo a 2-week intervention, either circuit-based PAS or sham PAS. Additionally, we explored the relationship between changes in cognitive performance and the functional connectivity (FC) of cortical-hippocampal circuits. RESULTS: FCs between hippocampus and precuneus and between hippocampus and superior frontal gyrus (orbital part) were most closely associated with the Auditory Verbal Learning Test (AVLT)_N5 score in 42 aMCI patients, thus designated as target circuits. The AVLT_N5 score improved from 2.43 (1.43) to 5.29 (1.98) in the circuit-based PAS group, compared with 2.52 (1.44) to 3.86 (2.39) in the sham PAS group (p=0.003; Cohen's d=0.97). A significant decrease was noted in FC between the left hippocampus and left precuneus in the circuit-based PAS group from baseline to postintervention (p=0.013). Using a generalised linear model, significant group×FC interaction effects for the improvements in AVLT_N5 scores were found within the circuit-based PAS group (B=3.4, p=0.017). CONCLUSIONS: Circuit-based PAS effectively enhances long-term delayed recall in adults diagnosed with aMCI, which includes individuals aged 50-80 years. This enhancement is potentially linked to the decreased functional connectivity between the left hippocampus and left precuneus. TRIAL REGISTRATION NUMBER: ChiCTR2100053315; Chinese Clinical Trial Registry.

Antimony-Triggered Tunable White Light Emission in Lead-Free Zero-Dimensional Indium Halide with Ultrastable CCT of White Light Emitting Diodes.

A highly efficient and easily tunable luminescence is significant for solid-state luminescent (SSL) materials. However, achieving a photoluminescence quantum yield (PLQY) close to unity and tuning the emission remain challenging tasks. Metal doping strategies enable resolution of these issues. Herein, we report the preparation of a novel organic-inorganic lead-free indium-based metal halide hybrid (MP)3InCl6•EtOH (MP = C4H10ON) with a typical zero-dimension structure. When excited at 320 nm, (MP)3InCl6•EtOH exhibits a dual emission band at 420 and 600 nm, which originates from the organic cation [MP] and the [InCl6]3- octahedral unit. The photoluminescence can be significantly enhanced through Sb3+ doping, resulting in an increase in PLQY from 0.78% to near unity. Multiple emission color tunings have been achieved by regulating the Sb doping level and the radiation wavelength, resulting in a change in emission color from blue → white → orange. Optical characterizations reveal that the significantly enhanced emission centered at 600 nm can be attributed to more efficient absorption, closely associated with an additional 1S0 → 3P1 transition in the inorganic octahedron [In(Sb)Cl6]3- due to Sb3+ doping. With its excellent optical performance, a white light emitting diode (WLED) has been successfully fabricated by coating the mixture of (MP)3InCl6•EtOH:15%Sb3+ with blue phosphor BaMgAl10O17:Eu2+ onto a UV LED chip. The WLED device exhibits perfect white light emission with regard to the International Commission on Illumination (CIE) coordinates of (0.36, 0.34). Significantly, the WLED device maintains a stable correlated color temperature (CCT) range of 4119-4393 K and CIE coordinates (x: 0.37-0.34, y: 0.35-0.33) as the driven current varies from 20 to 200 mA, demonstrating outstanding stability across different power levels. This work not only presents a novel system for achieving remarkably enhanced luminescent performance and tuning emission bands in 0D metal halides but also represents a significant step toward achieving resistance to color drifting for stable WLEDs.

Cucurbituril and zwitterionic surfactant-based matrix solid-phase dispersion microextraction to simultaneously determine terpenoids from Radix Curcumae.

A rapid, efficient, and environmentally friendly matrix solid-phase dispersion microextraction was established to determine and quantify terpenoids in Radix Curcumae using ultra-high-performance liquid chromatography with a diode array detector. Various parameters affecting the extraction were investigated in detail, such as the grinding time, amount of adsorbent, type and concentration of elution solvent, and pH. The optimization of single-factor and response surface methodology was performed to confirm the best conditions in this procedure. The final optimized conditions were obtained by applying 70 mg of cucurbituril as adsorbent, 149 s as the optimum grinding time, and 228 mM of 3-(N,N-dimethylpalmitylammonio)propanesulfonate aqueous solution (pH 6.5) as the optimal elution solvent. The validated method showed a satisfactory linear range of 0.10-10 µg/mL for curdione and furanodiene, 0.01-10 µg/mL for isocurcumenol and germacrone, and 0.05-10 µg/mL for furanodienone, while the correlation coefficients ranged from 0.9945 to 0.9970. The recoveries of the investigated analytes at two spiked concentration levels (0.1 and 1.0 µg/mL) ranged from 96.53 to 104.60%. In addition, this method displayed acceptable reproducibility (relative standard deviation ≤ 3.66%). The results showed that the newly proposed matrix solid-phase dispersion microextraction method was successfully applied to analyze curdione, isocurcumenol, furanodienone, germacrone and furanodiene in Radix Curcumae samples.

Plasma calprotectin was associated with platelet activation and no-reflow phenomenon in acute coronary syndrome.

BACKGROUND: No-reflow occurs in 3-4% of all percutaneous coronary interventions (PCIs) and has a strong negative impact on clinical outcomes of acute coronary syndrome (ACS). Therefore, the discovery of a biomarker that can early predict the occurrence of no-reflow has great clinical significance. Multiple factors including platelet activation are relevant to no-reflow. Calprotectin is found to be a biomarker of plaque instability and is identified to be a novel diagnostic and prognostic biomarker of cardiovascular diseases. The association of plasma calprotectin with platelet activation and no-reflow phenomenon in ACS is not clear. METHODS: In this prospective study performed at Yantai Yuhuangding Hospital from 2017 to 2018, a total of 176 Chinese patients with ACS who had undergone PCIs were recruited consecutively, aged from 30 to 88 years. Angiographic no-reflow was defined as thrombolysis in myocardial infarction grade less than 3. Blood samples were collected immediately at admission for the detection of plasma calprotectin and platelet-monocyte aggregates formation. Statistical analysis was performed for the variable's comparisons between groups and the prediction value of plasma calprotectin for no-reflow. RESULTS: The mean age of the 176 included ACS patients were 64(±11) years and acute ST-segment elevation myocardial infarction (STEMI) was present in 41.5% of patients. Twenty-two patients had no-reflow during the PCI procedures and the prevalence was 12.5%. Patients with higher plasma calprotectin had a higher level of platelet-monocyte aggregates (PMA) and a higher prevalence of no-reflow (p < 0.001). The multivariate regression showed that plasma calprotectin and admission hs-cTnI were independently associated with PMA, while plasma calprotectin and serum LDL-c were independent predictors of no-reflow (p < 0.001 and p = 0.017). AUC of calprotectin for predicting no-reflow were 0.898. The cut-off value of plasma calprotectin for no-reflow was 4748.77 ng/mL with a sensitivity of 0.95 and a specificity of 0.77. CONCLUSION: Plasma calprotectin was associated with platelet activation and may act as an early predictive biomarker of no-reflow in patients with acute coronary syndrome.

PAHs in road dust of Nanjing Chemical Industry Park, China: chemical composition, sources, and risk assessment.

The objectives of the present study were to research the chemical composition of PAHs in PM2.5 of road dust, explore potential sources of PAHs, and assess their carcinogenic risk. Fifty-six road dust samples were collected on the arterial and sub-arterial roads at Nanjing Chemical Industry Park during the sampling periods of autumn and winter. A resuspension system in the laboratory was used to simulate the naturally suspended road dust in the environment and collect PM2.5. Ace was not detected, but other PAHs were found. The pollution level of PAHs was 43.66 ± 15.79 mg kg-1; and 4-ring PAHs, which accounted for 35.14% of PAHs, were the main pollutants. The contents of BeP and BghiP were the highest, accounting for 12.23% and 12.06% of PAHs, respectively. The PAHs concentrations were found to be higher in winter due to the physicochemical characteristics of PAHs and the meteorological conditions. The sequence of PAHs concentrations was: sub-arterial road in winter > arterial road in winter > arterial road in autumn > sub-arterial road in autumn. Traffic emission and industrial sources led to higher PAHs concentrations on the arterial roads in autumn. Meteorological conditions and road characteristics, such as vehicular speed, frequency of road dust sweeping, and road width, led to higher PAHs concentrations on the sub-arterial roads in winter. Principal component analysis (PCA) and the ratios of Ant/(Ant + Phe), Flu/(Flu + Pyr), InP/(InP + BP), and BaA/(BaA + Chr) were used to distinguish the PAHs sources, which indicated fossil fuel combustion, traffic emissions, and petroleum exhaust as the main PAHs sources. The application of the ILCR model for PAHs in road dust showed a higher carcinogenic risk for children and adults (6.01 × 10-5 and 5.80 × 10-5, respectively) on the sub-arterial roads in winter, indicating a high potential carcinogenic risk at the Chemical Industrial Park.

Semi-supervised prediction of protein interaction sites from unlabeled sample information.

BACKGROUND: The recognition of protein interaction sites is of great significance in many biological processes, signaling pathways and drug designs. However, most sites on protein sequences cannot be defined as interface or non-interface sites because only a small part of protein interactions had been identified, which will cause the lack of prediction accuracy and generalization ability of predictors in protein interaction sites prediction. Therefore, it is necessary to effectively improve prediction performance of protein interaction sites using large amounts of unlabeled data together with small amounts of labeled data and background knowledge today. RESULTS: In this work, three semi-supervised support vector machine-based methods are proposed to improve the performance in the protein interaction sites prediction, in which the information of unlabeled protein sites can be involved. Herein, five features related with the evolutionary conservation of amino acids are extracted from HSSP database and Consurf Sever, i.e., residue spatial sequence spectrum, residue sequence information entropy and relative entropy, residue sequence conserved weight and residual Base evolution rate, to represent the residues within the protein sequence. Then three predictors are built for identifying the interface residues from protein surface using three types of semi-supervised support vector machine algorithms. CONCLUSION: The experimental results demonstrated that the semi-supervised approaches can effectively improve prediction performance of protein interaction sites when unlabeled information is involved into the predictors and one of them can achieve the best prediction performance, i.e., the accuracy of 70.7%, the sensitivity of 62.67% and the specificity of 78.72%, respectively. With comparison to the existing studies, the semi-supervised models show the improvement of the predication performance.

Solid acids assisted matrix solid-phase dispersion microextraction of alkaloids by capillary electrophoresis coupled with quadrupole time-of-flight mass spectrometry.

The quantification of three alkaloids is important because quantitative study is a means of assessing the reliability of the experimental method, and three alkaloids of peimine, peiminine, and peimisine are main active ingredients in Chinese Pharmacopoeia 2015. An effective method based on the matrix solid-phase dispersion microextraction was developed for the extraction of alkaloid compounds in Fritillariae Thunbergii Bulbus. Target analytes were analyzed by capillary electrophoresis coupled with quadrupole time-of-flight mass spectrometry. The optimized experimental condition was that 50 mg Fritillariae Thunbergii Bulbus was blended homogeneously with 10 mg citric acid for 5 min. Two hundred microliters of water acidized by 1 mol/L hydrochloric acid (pH = 4.5) was selected to elute tested alkaloids. The results demonstrated that the investigated method had low limits of detection (1.32-1.59 ng/mL), good recoveries (86.63-98.12%), and reproducibility (relative standard deviations of peak areas < 0.87%). The proposed matrix solid-phase dispersion microextraction coupled with capillary electrophoresis combined with quadrupole time-of-flight mass spectrometry was successfully applied for the extraction of alkaloids in plants.

Fusarium oxysporum KB-3 from Bletilla striata: an orchid mycorrhizal fungus.

Orchid mycorrhizal fungi are essential for the seed germination and vegetative growth of orchids. The orchid Bletilla striata has great medical value in China because its tuber is rich in mannan. Some endophytic fungi were isolated from the roots of B. striata. The isolate KB-3 was selected for experiments because it could promote the germination of B. striata seeds. Based on morphological characters and phylogenetic analysis, the isolate KB-3 was identified as Fusarium oxysporum. Co-cultivation experiments of KB-3 with B. striata and Dendrobium candidum were performed to demonstrate orchid mycorrhizal structures. Microscopic examination showed that KB-3 established colonization and produced coiled hyphal structures known as pelotons within the cortical cells of both orchid roots. The results confirm that F. oxysporum KB-3 can behave as an orchid mycorrhizal fungus.

Shikonin sensitizes A549 cells to TRAIL-induced apoptosis through the JNK, STAT3 and AKT pathways.

BACKGROUND: TRAIL, tumor necrosis factor-related apoptosis-inducing ligand, can selectively kill cancer cells with little or no cytotoxicity toward normal human cells and is regarded as a potential relatively safe antitumor drug. However, some cancer cells are resistant to TRAIL-induced apoptosis. Thus, reagents that potentiate TRAIL-induced cytotoxicity are needed. Herein, we investigated whether shikonin, a natural compound from the root of Lithospermum erythrorhizon, can sensitize TRAIL-resistant cells to TRAIL-induced cytotoxicity. RESULTS: The viability of A549 cells, which were resistant to TRAIL, was significantly decreased after treatment with TRAIL followed by shikonin. The underlying mechanisms by which shikonin sensitizes cells to TRAIL-induced cytotoxicity were also examined. Combined treatment with shikonin and TRAIL activated the caspase and JNK pathways, inhibited the STAT3 and AKT pathways, downregulated the expression of Mcl-1, Bcl-2, Bcl-xL, c-FLIP and XIAP and upregulated the expression of Bid. CONCLUSIONS: In conclusion, the results indicated that shikonin sensitized resistant cancer cells to TRAIL-induced cytotoxicity via the modulation of the JNK, STAT3 and AKT pathways, the downregulation of antiapoptotic proteins and the upregulation of proapoptotic proteins.

Aneurysm of the Anomalous Splenic Artery Arising from Superior Mesenteric Artery Treated by Coil Embolization: A Report of Two Cases and Literature Review.

BACKGROUND: Aneurysm of splenic artery (SA) which arises from the superior mesenteric artery (SMA) is a very rare condition. The aim of this study was to present our experience with 2 such patients treated by coil embolization. METHODS: A 33-year-old man and a 61-year-old woman were incidentally identified with aneurysms of the SA which arose from the SMA. Endovascular therapy of coil embolization was chosen to treat the aneurysm. RESULTS: Follow-up computed tomography showed no change in the location of the coils and occlusion of majority of the aneurysm sac. The 2 patients have been doing well during a 26-month and 10-month follow-up period, respectively. CONCLUSIONS: Combined with the experience of the previous literature, we think coil embolization can be cost-effective and minimally invasive in selected cases, depending on the morphology and site of the lesion.

Anti-influenza activity of berberine improves prognosis by reducing viral replication in mice.

Berberine, a natural isoquinoline alkaloid isolated from the berberis species, has a wide array of biological properties such as anti-inflammatory, antibacterial, antifungal, and antihelminthic effects. We evaluated the antiviral effect of berberine against influenza A/FM1/1/47 (H1N1) in vivo and in vitro. The results showed that berberine strongly suppressed viral replication in A549 cells and in mouse lungs. Meanwhile, berberine relieved pulmonary inflammation and reduced necrosis, inflammatory cell infiltration, and pulmonary edema induced by viral infection in mice when compared with vehicle-treated mice. Berberine suppressed the viral infection-induced up-regulation of TLR7 signaling pathway, such as TLR7, MyD88, and NF-κB (p65), at both the mRNA and protein levels. Furthermore, berberine significantly inhibited the viral infection-induced increase in Th1/Th2 and Th17/Treg ratios as well as the production of inflammatory cytokines. Our data provide new insight into the potential of berberine as a therapeutic agent for viral infection via its antiviral activity.

Chimeric antigen receptor-engineered T-cell therapy for liver cancer.

BACKGROUND: Chimeric antigen receptor-engineered T-cell (CAR-T) therapy is a newly developed immunotherapy used in the treatment of cancers. Because CAR-T therapy has shown great success in treating CD19-positive hematological malignancies, its application has been explored in the treatment of solid tumors, such as liver cancer. In this review, we discuss the immune characteristics of liver cancer, the obstacles encountered during the application of CAR-T therapy, and preclinical and clinical progress in the use of CAR-T therapy in patients with liver cancer. DATA SOURCES: The data on CAR-T therapy related to liver cancers were collected by searching PubMed and the Web of Science databases prior to December 2017 with the keywords "chimeric antigen receptor", "CAR-T", "liver cancer", "hepatocellular carcinoma", and "solid tumor". Additional articles were identified by manual search of references found in the primary articles. The data for clinical trials were collected by searching ClinicalTrials.gov. RESULTS: The liver has a tolerogenic nature in the intrahepatic milieu and its tumor microenvironment significantly affects tumor progression. The obstacles that reduce the efficacy of CAR-T therapy in solid tumors include a lack of specific tumor antigens, limited trafficking and penetration of CAR-T cells to tumor sites, and an immunosuppressive tumor microenvironment. To overcome these obstacles, several strategies have emerged. In addition, several strategies have been developed to manage the side effects of CAR-T, including enhancing the selectivity of CARs and controlling CAR-T activity. To date, no clinical trials of CAR-T therapy against HCC have been completed. However, preclinical studies in vitro and in vivo have shown potent antitumor efficacy. Glypican-3, mucin-1, epithelial cell adhesion molecule, carcinoembryonic antigen, and other targets are currently being studied. CONCLUSIONS: The application of CAR-T therapy for liver cancer is just beginning to be explored and more research is needed. However, we are optimistic that CAR-T therapy will offer a new approach for the treatment of liver cancers in the future.

CaMKII inhibition mitigates ischemia/reperfusion-elicited calpain activation and the damage to membrane skeleton proteins in isolated rat hearts.

Ca2+/calmodulin-dependent protein kinase II (CaMKII) has been implicated in myocardial ischemia/reperfusion (IR) injury. The aim of this study was to determine the effect of CaMKII on the damage to membrane skeleton proteins, which is an important cause of IR injury. Isolated rat hearts were subjected to 45-min global ischemia/2-h reperfusion. Both KN-62 and KN-93 were used to inhibit CaMKII. Compared with controls, the hearts in the IR group exhibited remarkable myocardial injury area, LDH release, cell apoptosis and contractile dysfunction, along with an increase in the phosphorylation of CaMKII and its substrate phospholamban. Treatment with either KN-62 or KN-93 mitigated both the heart injury and the phosphorylation of CaMKII and phospholamban. The analysis of cell skeleton proteins revealed that IR injury resulted in an increase in the 150-kDa fragments resulting from the degradation of α-fodrin and dystrophin translocating from the sarcolemmal membrane to the cytosol and a decrease in the 220-kDa isoform of ankyrin-B. As expected, Evans blue dye staining showed an increase in membrane permeability or membrane rupture in the IR group. All of these alterations were alleviated by treatment with either KN-62 or KN-93. In addition, both KN-62 and KN-93 blocked the activity and membrane recruitment of calpain, a key protease responsible for destroying cell skeleton proteins during IR injury. In conclusion, our data provide evidence that damage to membrane skeleton proteins via calpain is a destructive downstream event of CaMKII activation in the setting of myocardial IR injury.

2,3,5,4'-Tetrahydroxystilbene-2-O-ß-D-glucoside protects murine hearts against ischemia/reperfusion injury by activating Notch1/Hes1 signaling and attenuating endoplasmic reticulum stress.

2,3,5,4'-Tetrahydroxystilbene-2-O-ß-D-glucoside (TSG) is a water-soluble active component extracted from Polygonum multiflorum Thunb. A number of studies demonstrate that TSG exerts cardioprotective effects. Since endoplasmic reticulum (ER) stress plays a key role in myocardial ischemia/reperfusion (MI/R)-induced cell apoptosis, we sought to determine whether modulation of the ER stress during MI/R injury was involved in the cardioprotective action of TSG. Male mice were treated with TSG (60 mg·kg-1·d-1, ig) for 2 weeks and then were subjected to MI/R surgery. Pre-administration of TSG significantly improved post-operative cardiac function, and suppressed MI/R-induced myocardial apoptosis, evidenced by the reduction in the myocardial apoptotic index, serum levels of LDH and CK after 6 h of reperfusion. TSG (0.1-1000 µmol/L) did not affect the viability of cultured H9c2 cardiomyoblasts in vitro, but pretreatment with TSG dose-dependently decreased simulated ischemia/reperfusion (SIR)-induced cell apoptosis. Furthermore, both in vivo and in vitro studies revealed that TSG treatment activated the Notch1/Hes1 signaling pathway and suppressed ER stress, as evidenced by increasing Notch1, Notch1 intracellular domain (NICD), Hes1, and Bcl-2 expression levels and by decreasing p-PERK/PERK ratio, p-eIF2α/eIF2α ratio, and ATF4, CHOP, Bax, and caspase-3 expression levels. Moreover, the protective effects conferred by TSG on SIR-treated H9c2 cardiomyoblasts were abolished by co-administration of DAPT (the Notch1 signaling inhibitor). In summary, TSG ameliorates MI/R injury in vivo and in vitro by activating the Notch1/Hes1 signaling pathway and attenuating ER stress-induced apoptosis.

Synthesis and activity evaluation of the cyclic dipeptides arylidene N-alkoxydiketopiperazines.

A series of arylidene N-alkoxydiketopiperazines was designed and stereoselectively synthesized via oxime-ether formation and intramolecular acylation. Possible cyclization and acid-catalyzed rearrangement-fragmentation mechanisms were discussed. The crystal structure of the novel diketopiperazine further confirmed the rearrangement mechanism. Most compounds exhibited antitumor activity. Several compounds were more potent against caspase-3. Specifically, compounds 6e, 6g, and 6f inhibited caspase-3 at IC50 values lying within the low micromolar range and demonstrated good selectivity. The binding modes of alkoxydiketopiperazines in the active center of caspase-3 were also discussed based on the molecular docking results.

Berberine protects rat heart from ischemia/reperfusion injury via activating JAK2/STAT3 signaling and attenuating endoplasmic reticulum stress.

AIM: Berberine (BBR), an isoquinoline-derived alkaloid isolated from Rhizoma coptidis, exerts cardioprotective effects. Because endoplasmic reticulum (ER) stress plays a pivotal role in myocardial ischemia/reperfusion (MI/R)-induced apoptosis, it was interesting to examine whether the protective effects of BBR resulted from modulating ER stress levels during MI/R injury, and to define the signaling mechanisms in this process. METHODS: Male rats were treated with BBR (200 mg · kg(-1) · d(-1), ig) for 2 weeks, and then subjected to MI/R surgery. Cardiac dimensions and function were assessed using echocardiography. Myocardial infarct size and apoptosis was examined. Total serum LDH levels and CK activities, superoxide production, MDA levels and the antioxidant SOD activities in heart tissue were determined. An in vitro study was performed on cultured rat embryonic myocardium-derived cells H9C2 exposed to simulated ischemia/reperfusion (SIR). The expression of apoptotic, ER stress-related and signaling proteins were assessed using Western blot analyses. RESULTS: Pretreatment with BBR significantly reduced MI/R-induced myocardial infarct size, improved cardiac function, and suppressed myocardial apoptosis and oxidative damage. Furthermore, pretreatment with BBR suppressed MI/R-induced ER stress, evidenced by down-regulating the phosphorylation levels of myocardial PERK and eIF2α and the expression of ATF4 and CHOP in heart tissues. Pretreatment with BBR also activated the JAK2/STAT3 signaling pathway in heart tissues, and co-treatment with AG490, a specific JAK2/STAT3 inhibitor, blocked not only the protective effects of BBR, but also the inhibition of BBR on MI/R-induced ER stress. In H9C2 cells, treatment with BBR (50 µmol/L) markedly reduced SIR-induced cell apoptosis, oxidative stress and ER stress, which were abolished by transfection with JAK2 siRNA. CONCLUSION: BBR ameliorates MI/R injury in rats by activating the AK2/STAT3 signaling pathway and attenuating ER stress-induced apoptosis.

Glutamate protects against Ca(2+) paradox-induced injury and inhibits calpain activity in isolated rat hearts.

This study determined the effects of glutamate on the Ca(2+) paradoxical heart, which is a model for Ca(2+) overload-induced injury during myocardial ischaemia and reperfusion, and evaluated its effect on a known mediator of injury, calpain. An isolated rat heart was retrogradely perfused in a Langendorff apparatus. Ca(2+) paradox was elicited via perfusion with a Ca(2+) -free Krebs-Henseleit (KH) solution for 3 minutes followed by Ca(2+) -containing normal KH solution for 30 minutes. The Ca(2+) paradoxical heart exhibited almost no viable tissue on triphenyltetrazolium chloride staining and markedly increased LDH release, caspase-3 activity, cytosolic cytochrome c content, and apoptotic index. These hearts also displayed significantly increased LVEDP and a disappearance of LVDP. Glutamate (5 and 20 mmol/L) significantly alleviated Ca(2+) paradox-induced injury. In contrast, 20 mmol/L mannitol had no effect on Ca(2+) paradox. Ca(2+) paradox significantly increased the extent of the translocation of µ-calpain to the sarcolemmal membrane and the proteolysis of α-fodrin, which suggests calpain activation. Glutamate also blocked these effects. A non-selective inhibitor of glutamate transporters, dl-TBOA (10 µmol/L), had no effect on control hearts, but it reversed glutamate-induced cardioprotection and reduction in calpain activity. Glutamate treatment significantly increased intracellular glutamate content in the Ca(2+) paradoxical heart, which was also blocked by dl-TBOA. We conclude that glutamate protects the heart against Ca(2+) overload-induced injury via glutamate transporters, and the inhibition of calpain activity is involved in this process.

The Blockade of Transmembrane Cl⁻ Flux Mitigates I/R-Induced Heart Injury via the Inhibition of Calpain Activity.

AIMS: The aim of this study was to determine whether calpain is involved in Cl(-)-induced myocardial ischemia/reperfusion (I/R) injury. METHODS: Isolated rat hearts were subjected to either 45 min of global no-flow ischemia followed by reperfusion or successive perfusion with Ca(2+)-free KH solution for 3 min and normal KH solution for 30 min, also known as Ca(2+) paradox. RESULTS: The hearts in the I/R group exhibited increases in myocardial injury area, LDH release, caspase 3 activity and apoptotic indices and a marked decline in cardiac performance. As was the case regarding the effects of MDL 28170, an inhibitor of calpain, treatment with 5 µM NPPB, 5 µM DIDS and low Cl(-) significantly attenuated cardiac injury. Moreover, each of the treatments significantly protected against Ca(2+) overload-induced injury in the setting of Ca(2+) paradox. The Western blot and immunofluorescence data revealed that there was an increase in the percentages of calpain membrane-positive cells and the numbers of fragments resulting from the calpain-mediated proteolysis of α-fodrin in both the I/R and the Ca(2+) paradox, indicating that the activation of calpain occurred. More importantly, these effects were mitigated by the blockade of transmembrane Cl(-) flux, as was accomplished via MDL 28170. CONCLUSION: Our results provide evidence that the blockade of transmembrane Cl(-) flux mitigates I/R-induced cardiac injury via the inhibition of calpain activity. They also indicate that intracellular Ca(2+) overload regulates calpain activation in the setting of Cl(-)-induced injury.

Synthesis and biological evaluation of open-chain analogs of cyclic peptides as inhibitors of cellular Shp2 activity.

A series of open-chain analogs of cyclic peptides was designed and synthesized using sansalvamide A as a model compound. All compounds exhibited low antitumor activity. Furthermore, the evaluation of their inhibitory potency toward IMPDH, SHP2, ACHE, proteasome, MAGL, and cathepsin B showed that all of the compounds were potent against protein tyrosine phosphatase Shp2. Specifically, compounds 1a, 1d, 2b, and 2f were found to inhibit SHP2 with IC50 values in the low micromolar range and good selectivity. Based on the molecular docking results, the binding modes of the chain cyclic peptides in the active center of SHP2 were discussed.

[Study on inhibitory effect of water extract of Polygonum multiflorum on CYP1A2 and CYP2E1 enzymatic activities and mRNA expressions in rat liver].

Rats were continuously given different doses of water extract of Polygonum multiflorum (1, 10 g x kg(-1)) for 7 days to prepare liver microsomes. Cocktail in vitro incubation approach and Real-time quantitative PCR technology were used to observe the effect of water extract of P. multiflorum on CYP450 enzymatic activities and mRNA expressions in rat liver. Compared with the blank control group, both 1, 10 g x kg(-1) water extract of P. multiflorum treated groups showed significant inhibitions in CYP2E1 enzymatic activities and mRNA expressions (enzymatic activities of CYP2E1, P < 0.01; mRNA expression of CYP2E1, P < 0.05 in 1 g x kg(-1) group, P < 0.01 in 10 g x kg(-1) group). They revealed a significant increase in the enzymatic activity of CYP3A1 (P < 0.01), but without significant change in mRNA expressions. The 10 g x kg(-1) group showed a significant inhibition in CYP1A2 enzymatic activities and mRNA expressions in rat livers (P < 0.01).