Search

Background Protection the heart from ischemia/reperfusion (I/R) injury is an area of intense research, as myocardial infarction is a major cause of mortality and morbidity all around the world. Tournefolic acid B (TAB) is a relative new compound derived from Clinopodium chinense (Benth.) Kuntze (Chinese name: Feng Lun Cai). This traditional Chinese herbal medicine has been used for its activities on anti-inflammatory, lowering blood glucose, antitumor and antiradiation. However, the pharmacological effects of TAB were rarely studied. Purpose Pathways involving phosphoinositide 3-kinase (PI3K) and protein kinase b (Akt) are crucial in regulating the ER stress and associated apoptosis in the process of I/R injury. In the present study, we aim to investigate the cardioprotective effects of tournefolic acid B (TAB) against myocardial I/R injury and explore the molecular mechanisms involved. Study design H9c2 cadiomyocyte were incubated with TAB for 24 h and then exposed to hypoxia/reoxygenation. Isolated rat hearts were subjected to global ischemia and reperfusion in the absence or presence of TAB. Methods The possible mechanisms were investigated in vitro and ex vivo by multiple detection methods including JC-1 staining, ROS detection, activities of caspases detection, TUNEL staining, and Western-blot analysis. Results We found that TAB significantly improved the hemodynamic parameters (LVeDP, LVSP, + dP/dtmax, − dP/dtmin, and HR) of isolated rat hearts, and depressed the cardiomyocyte apoptosis. Besides, TAB inhibited the oxidative stress by adjusting the activities of antioxidant enzymes (SOD, CAT, and GSH-Px). The I/R injury triggered the endoplasmic reticulum (ER) stress by activating the ER proteins, such as Grp78, ATF6, PERK, and eIf2α. which are all refrained by TAB. TAB also enhanced the phosphorylation of PI3K and AKT, inhibited the expression of CHOP and Caspase-12, reduced the phosphorylation of JNK, and increased Bcl-2/Bax ratio. Conclusion TAB protects against myocardial I/R injury by suppressing PI3K/AKT-mediated ER stress, oxidative stress, and apoptosis, revealing a promising therapeutic agent against ischemic cardiovascular diseases.

Estrogen plays a pivotal role in the pathological development of breast cancer. Resveratrol has chemo-preventive effects against breast cancer, whereas, the mechanism of antitumor activities of resveratrol remains unanswered. In this study, we showed that estrogen homeostasis profile was disturbed in both breast cancer patients and in experimental breast cancer model rats, with carcinogenic catechol estrogens significantly accumulated in the mammary tissues. UDP-glucuronosyltransferase 1A8 (UGT1A8) is an important phase II drug-metabolizing enzymes which involved in the metabolism of catechol estrogens. Here we found that the mammary nuclear factor erythroid 2-related factor 2 (NRF2) – UGT1A8 signaling was down-regulated in breast cancer rats, whereas treatment with resveratrol could upregulate the expression of NRF2 and UGT1A8, accelerate metabolic elimination of catechol estrogens, inhibit estrogen-induced DNA damage and suppress the pathological development of breast cancer. In addition, luciferase reporter assay suggested that resveratrol activated the expression of UGT1A8 by up-regulating the transcriptional activity of NRF2. Small-interfering RNA-mediated silencing of NRF2 abolished resveratrol-mediated preventive effects indicated that the antitumor effect of resveratrol is based on NRF2-UGT1A8-estrogen metabolism axis. Taken together, we established the resveratrol regulating potential on estrogen homeostasis based on NRF2-UGT1A8 signaling pathway, and also provided a novel link between estrogen glucuronidation metabolism and breast cancer pathological development.

Two new flavonoid–triterpene saponin meroterpenoids, clinoposides G (1) and H (2) were isolated from the aerial parts of Clinopodium chinense (Benth.) O. Kuntze. Their structures were elucidated through spectroscopic and electronic circular dichroism (ECD) analyses. Compounds 1 and 2 were evaluated for their protective effects against anoxia/reoxygenation(A/R)-induced injury in H9c2 cells. A/R treatment severely injured the H9c2 cells, which was accompanied by apoptosis. Both 1 and 2 pretreatment significantly inhibited cell injury and apoptosis, improved mitochondrial membrane potential, increased activities of antioxidant enzymes, and reduced the levels of the inflammatory cytokines. In addition, the presence of 1 and 2 significantly decreased the protein level of p65 and increased the level of Nrf2 in cell nucleus. Unique chemical structure and good biological activity of 1 and 2 elucidated the potential of meroterpenoids as a promising reagent for treating heart disease.

We present a facile particle-based cell manipulation method using acoustic radiation forces. In this work, we selected several representative particles including poly(lactic-co-glycolic acid) (PLGA) microspheres, silica-coated magnetic microbeads, polydimethylsiloxane (PDMS) microspheres and investigated the responses of these particle systems to ultrasonic standing waves (USWs) in a microfluidic chip. We show that depending on the nature (positive or negative acoustic contrast factors) of the particles, these particle systems display different alignment behaviors along the microfluidic channel under USWs. Specifically, PLGA microspheres and silica-coated magnetic microbeads are able to be aligned in the middle of the microfluidic channel, while PDMS microspheres are translocated to the side walls of the channel, which is beneficial for cell trapping and manipulation. Further results demonstrate that the functional PDMS microspheres with a negative acoustic contrast factor can be used to trap cells to the pressure antinodes in the acoustofluidic chip. Cell viability tests reveal that the ultrasonic manipulation does not exert any harmful effect to the cells. This acoustic-based particle and cell manipulation technique may hold a great promise for the development of rapid, noninvasive, continuous assays for detecting of cells and separation of biological samples.

Two novel 16-membered tetraene marcolides, bafilomycins N (1) and O (2), along with two known analogues, JBIR-100 (3) and bafilomycin K (4) were produced from isolate GIC10-1, a Streptomyces sp. strain that was originally cloned from bacterial communities associated with marine sponge Theonella sp. The structures of new bafilomycins 1 and 2 were established by using spectroscopic methods and comparing the spectroscopic data with those of known related metabolites. Compounds 1 and 2 were proven to be the first 14-methylbafilomycins to be isolated. Cytotoxicity of these compounds toward various cancer cell lines also is described.

Hydrogen evolution reaction (HER) in water splitting plays an important role in the storage and conversion of clean energy. The development of efficient electrocatalytic materials for HER has attracted much attention in current research. In this work, a homogeneous NiFe-based prussian blue analogue (NiFe-PBA) thin film is prepared on the surface of nickel foam by liquid phase epitaxial (LPE) layer-by-layer (LBL) dipping method. Then the NiFe-PBA film reacts with PH3 produced by sodium hypophosphite to form a bimetal phosphide NiFeP film. The electrocatalytic HER properties under alkaline condition indicate that the NiFeP film only requires 99 ​mV overpotential to reach 10 ​mA ​cm−2 and the performance can be maintained for over 30 ​h without obvious degradation even at 100 ​mA ​cm−2. The results imply that the prepared NiFeP film has excellent HER performance and durable stability. This work is of great significance for the preparation of self-supporting and low-cost bimetal phosphide thin film for efficient HER.

Columnaristerol A ( 1 ), a rare natural 19-norsterol possessing a 10β-hydroxy group was isolated from the Formosan octocoral Nephthea columnaris , and its structure was elucidated by spectroscopic methods. Sterol 1 was found to be a cytotoxic agent that exhibited in vitro moderate cytotoxic activity against MOLT-4 and SUP-T1 human leukemia–lymphoma cell lines.

Two new eunicellin-type diterpenoids, cladieunicellins R ( 1 ) and S ( 2 ), were isolated from the octocoral Cladiella tuberculosa and their structures were elucidated by spectroscopic methods. Eunicellin 1 was proven to be the first 2,6-hemiketal eunicellin and 2 was found to exhibit moderate cytotoxicity toward the MOLT-4, K562, and SUP-T1 cells.

Eight new briarane diterpenoids, designated briarenolides M–T (1–8), were isolated from an octocoral identified as Briareum sp. The structures of briaranes 1–8 were established by spectroscopic methods and by comparison of the spectroscopic data with those of known analogues. The relationship between 1H and 13C NMR chemical shifts of 2-hydroxybriaranes possessing of (A) a Δ3,5(16)-conjugated diene moiety or (B) a Δ3,5-conjugated diene moiety are described. Briarenolides M (1), P (4), S (7), and T (8) were found to inhibit the accumulation of the pro-inflammatory inducible nitric oxide synthase (iNOS) protein and briarenolides N (2), P (4), and T (8) were found to inhibit the accumulation of the pro-inflammatory cyclooxygenase-2 (COX-2) protein in LPS (lipopolysaccharide)-stimulated RAW264.7 macrophage cells.

Ultra-compact TE/TM polarization splitters in LiNbO 3 photonic wires with same bending waveguide in input and output transition regions at 1.31 μm and 1.55 μm wavelengths have been proposed, respectively. Their operating principles are based on the directional coupling mode. Their optimization designs are achieved by using commercial software COMSOL Multiphysics. Calculated steady-state field distributions indicate that guided lightwaves in both quasi-TM and quasi-TE polarizations can be spatially separated from different output waveguides ports. The transmittances of quasi-TE and quasi-TM polarization at 1.31 μm wavelength are 90% and 88.5%, respectively. And that at 1.55 μm are 88.6% and 84.7%, respectively. The total lengths of the devices for 1.31 μm and 1.55 wavelengths are 47 μm and 36.52 μm, respectively. Moreover, the coupling length dependences of the transmittances, the optical transmission bandwidths, and fabrication sensitivities are evaluated, respectively. The simple and compact polarization splitters are expected to be applied to highly dense LN photonic integrated circuits.

A new 16-membered diene macrolide, bafilomycin M ( 1 ), was produced from a Streptomyces sp. GIC10-1, which was originally isolated from a marine sponge Theonella sp. The structure of 1 was established by spectroscopic methods and this compound was found to exhibit cytotoxicity toward K-562, HL-60, SUPT-1, and LNCaP tumor cells with IC 50 values 0.060, 0.011, 0.047, and 0.389 μg/mL, respectively.

Three new cassane furanoditerpenes, phanginins N–P (1–3), together with four known ones were isolated from the seeds of Caesalpinia sappan. Their structures were elucidated on the basis of spectroscopic analysis including HRESIMS, 1D and 2D NMR techniques. Evaluation of all the compounds for cytotoxicity against three human cancer cell lines (HepG-2, MCF-7 and HCT-8) showed insignificant results (IC50 > 10 μM).