Three new antinociceptive diterpenoids from the fruits of Rhododendron molle.

Investigation of the fruits of Rhododendron molle G. Don led to the isolation of three new grayanane-type diterpenoids, rhodomolleins LIV-LVI (1-3). The structures and absolute configurations of new compounds were fully elucidated by spectroscopic analysis and single-crystal X-ray diffraction, including HRESIMS, 1 D and 2 D NMR data. Compounds 1-3 were evaluated for analgesic activities utilizing an acetic acid-induced writhing test in mice. Compound 1 showed a significant antinociceptive effect with writhe inhibition rates of 72.9% and 100% at doses of 6 mg/kg and 20 mg/kg in mice, respectively. The binding mode of 1 to N-ethylmaleimide-sensitive factor (NSF, PDB: 6IP2) was explored by molecular docking, indicating the presence of hydrogen bond interactions which account for its analgesic activity.

Three new antinociceptive diterpenoids from the roots of Rhododendron micranthum.

Two new grayanane-type (1 and 2) and one new kalmane-type diterpenoids (3), together with 16 known compounds, were isolated from the roots of Rhododendron micranthum. The structures of new compounds were fully determined on the basis of spectroscopic analysis, including HRESIMS, 1 D and 2 D NMR data. An acetic acid-induced writhing test in mice was proceeded to evaluate the antinociceptive activities of compounds 1-3, 5-6, 9-14 and 16. Compared to vehicle-injected mice, compounds 1, 6, 14 and 16 showed significant antinociceptive effects with writhe inhibition rates of 45.8%-64.2% at a dose of 0.1 mg/kg, and compounds 10, 12 and 13 showed significant antinociceptive effects with writhe inhibition rates of 33.9%-64.8% at a dose of 5 mg/kg. Compound 2 showed potent antinociceptive effects with writhe inhibition rates of 86.1% and 54.7% at doses of 8 mg/kg and 0.8 mg/kg, respectively. [Formula: see text].

S-Nitrosylation of Divalent Metal Transporter 1 Enhances Iron Uptake to Mediate Loss of Dopaminergic Neurons and Motoric Deficit.

Elevated iron deposition has been reported in Parkinson's disease (PD). However, the route of iron uptake leading to high deposition in the substantia nigra is unresolved. Here, we show a mechanism in enhanced Fe2+ uptake via S-nitrosylation of divalent metal transporter 1 (DMT1). While DMT1 could be S-nitrosylated by exogenous nitric oxide donors, in human PD brains, endogenously S-nitrosylated DMT1 was detected in postmortem substantia nigra. Patch-clamp electrophysiological recordings and iron uptake assays confirmed increased Mn2+ or Fe2+ uptake through S-nitrosylated DMT1. We identified two major S-nitrosylation sites, C23 and C540, by mass spectrometry, and DMT1 C23A or C540A substitutions abolished nitric oxide (NO)-mediated DMT1 current increase. To evaluate in vivo significance, lipopolysaccharide (LPS) was stereotaxically injected into the substantia nigra of female and male mice to induce inflammation and production of NO. The intranigral LPS injection resulted in corresponding increase in Fe2+ deposition, JNK activation, dopaminergic neuronal loss and deficit in motoric activity, and these were rescued by the NO synthase inhibitor l-NAME or by the DMT1-selective blocker ebselen. Lentiviral knockdown of DMT1 abolished LPS-induced dopaminergic neuron loss.SIGNIFICANCE STATEMENT Neuroinflammation and high cytoplasmic Fe2+ levels have been implicated in the initiation and progression of neurodegenerative diseases. Here, we report the unexpected enhancement of the functional activity of transmembrane divalent metal transporter 1 (DMT1) by S-nitrosylation. We demonstrated that S-nitrosylation increased DMT1-mediated Fe2+ uptake, and two cysteines were identified by mass spectrometry to be the sites for S-nitrosylation and for enhanced iron uptake. One conceptual advance is that while DMT1 activity could be increased by external acidification because the gating of the DMT1 transporter is proton motive, we discovered that DMT1 activity could also be enhanced by S-nitrosylation. Significantly, lipopolysaccharide-induced nitric oxide (NO)-mediated neuronal death in the substantia nigra could be ameliorated by using l-NAME, a NO synthase inhibitor, or by ebselen, a DMT1-selective blocker.

Pin1 promotes neuronal death in stroke by stabilizing Notch intracellular domain.

OBJECTIVE: Stroke is a leading cause of mortality and disability. The peptidyl-prolyl cis/trans isomerase Pin1 regulates factors involved in cell growth. Recent evidence has shown that Pin1 plays a major role in apoptosis. However, the role of Pin1 in ischemic stroke remains to be investigated. METHODS: We used Pin1 overexpression and knockdown to manipulate Pin1 expression and explore the effects of Pin1 in cell death on ischemic stress in vitro and in a mouse stroke model. We also used Pin 1 inhibitor, γ-secretase inhibitor, Notch1 intracellular domain (NICD1)-deleted mutant cells, and Pin1 mutant cells to investigate the underlying mechanisms of Pin1-NICD1-mediated cell death. RESULTS: Our findings indicate that Pin1 facilitates NICD1 stability and its proapoptotic function following ischemic stroke. Thus, overexpression of Pin1 increased NICD1 levels and enhanced its potentiation of neuronal death in simulated ischemia. By contrast, depletion or knockout of Pin1 reduced the NICD1 level, which in turn desensitized neurons to ischemic conditions. Pin1 interacted with NICD1 and increased its stability by inhibiting FBW7-induced polyubiquitination. We also demonstrate that Pin1 and NICD1 levels increase following stroke. Pin1 heterozygous (+/-) and knockout (-/-) mice, and also wild-type mice treated with an inhibitor of Pin1, each showed reduced brain damage and improved functional outcomes in a model of focal ischemic stroke. INTERPRETATION: These results suggest that Pin1 contributes to the pathogenesis of ischemic stroke by promoting Notch signaling, and that inhibition of Pin1 is a novel approach for treating ischemic stroke.

Pharmacological or Genetic Activation of Hsp70 Protects against Loss of Parkin Function.

Mutations of parkin are a prevalent genetic contributor to familial Parkinson's disease (PD). As a key regulator of protein and mitochondrial homeostasis, parkin plays a pivotal role in maintaining dopaminergic neuronal survival. However, whereas Drosophila parkin null mutants exhibit prominent parkinsonian features, parkin-deficient mice generally lack an overt phenotype. Here, we found that the expression of Hsp70 along with several other members of the chaperone family is elevated in parkin null mice, suggesting a possible compensatory mechanism for the loss of parkin function in these mice that could have masked their phenotype. Supporting this, we demonstrate that the enhancement of chaperone function induced either pharmacologically via 17-AAG treatment or genetically via Hsp70 overexpression can protect cells against proteolytic and mitochondrial stress in a manner that is similar to that brought about by parkin overexpression. Importantly, we further showed that enhanced chaperone activity can ameliorate the pathological phenotypes in Drosophila parkin null mutants, which suggests the ability of chaperones to phenocopy parkin function. Taken together, our results suggest that Hsp members may act as compensatory factors for parkin loss of function and that the exploitation of these factors may be of potential therapeutic value.

A Small-Molecule Probe for Selective Profiling and Imaging of Monoamine Oxidase†B Activities in Models of Parkinson's Disease.

The design of the first dual-purpose activity-based probe of monoamine oxidase B (MAO-B) is reported. This probe is highly selective towards MAO-B, even at high MAO-A expression levels, and could sensitively report endogenous MAO-B activities by both in situ proteome profiling and live-cell bioimaging. With a built-in imaging module as part of the probe design, the probe was able to accomplish what all previously reported MAO-B imaging probes failed to do thus far: the live-cell imaging of MAO-B activities without encountering diffusion problems.

17α-ethynylestradiol and its two main conjugates in seven municipal wastewater treatment plants: Analytical method, their occurrence, removal and risk evaluation.

This work shows the existence of both 17-ethinylestradiol-3-sulfate (EE2-3S) and 17-ethinylestradiol-3-glucuronide (EE2-3G) in seven municipal WWTPs with substantial concentrations (n.d-50.10 ng/L). The calculated removal efficiencies of 17-ethinylestradiol (EE2) in the seven municipal WWTPs ranged from 40.8%-100% with an average removal efficiency of 83.3%. However, upon the inclusion of EE2 concentration transformed from EE2-3S and EE2-3G, the corresponding removal efficiencies were increased to 91.4%-100% with an average removal efficiency of 97.3%. This work is the first to clearly illustrate that EE2 conjugates in raw wastewater could greatly underestimate the removal effectiveness of municipal WWTPs on EE2, indicating the importance of the EE2 conjugates in municipal wastewater having been hardly paid with attention. The EE2-derived estrogen equivalence (EEQ) values in the effluents of seven WWTPs ranged from 0 to 0.98 ng E2/L having an average level of 0.45 ng E2/L, which were relatively low. However, upon the inclusion of EE2 transformable from EE2-3S and EE2-3G in effluents, the EE2-derived EEQ values in effluents would be increased to 0.77-4.85 ng E2/L having an average level of 2.71 ng E2/L, which clearly suggested that ignorance of EE2 conjugates in effluent would largely underestimate EE2's environmental risk to receiving water bodies.

A model of hepatitis B virus with random interference infection rate.

According to the mechanism of drug inhibition of hepatitis B virus and the analysis of clinical data, it is found that random factors in long-term treatment produced uncertainty and resistance to hepatitis B virus infection rate, a model of hepatitis B virus with random interference infection rate is established. By constructing Lyapunov function and using Ito's formula, it is proved that the stochastic hepatitis B model has a unique global positive solution. The sufficient conditions for the asymptotic behavior of solution are given. The relationship between noise intensity and oscillation amplitude is obtained. The effects of noise intensity on the asymptotic behavior of the model and antiviral therapy are simulated, and the conclusion of the theorem is verified. An interesting phenomenon is also found that with the increase of noise intensity, the number of drug-resistant viruses will decrease, which will affect the accuracy of a single test of HBV DNA. Therefore, it is suggested to increase the frequency and interval of tests.

[Relationships Between Microplastic and Surrounding Soil in an E-Waste Zone of China].

Microplastic pollution is ubiquitous and has attracted significant public attention. Recent research on microplastic has focused on aquatic environments, but its impacts on soil ecosystems remain poorly understood, especially in e-waste dismantling zones. The objective of this study was to investigate the relationships between microplastic and surrounding soil in abandoned e-waste disassembling plots with different dismantling methods focusing on ecotoxicology and microbiology in Guiyu, Shantou District, Guangdong Province. The surface morphology of collected microplastics showed signs of aging and degradation, possibly due to their long-term exposure in the soil and the original disassembling methods. In addition, there were diverse metal elements at different surface positions of the same microplastic sample based on SEM-EDS analyses, indicating that some metal elements carried by microplastics are derived from the surrounding soil rather than being inherent to the microplastic. Moreover, seven heavy metals (Pb, Cd, Cr, As, Ba, Co, and Ni) inherent in microplastic were identified using ICP-OES, revealing that the concentrations varied in different sampling plots were typically higher than in the surrounding soil. In particular, the concentration of Ba in microplastic was 103 orders of magnitude higher than in soil. Indeed, Ba in the form of BaSO4 is widely used as a filler in numerous plastics. Furthermore, microplastic-associated microorganisms were examined using 16S rRNA sequencing, and the relationships between the top 50 genera of microplastic-bound bacteria and soil environmental factors were analyzed using the Spearman's rank correlation coefficient. Microorganisms primarily originated from the surroundings of microplastics; therefore, environmental factors could directly affect the microbial communities associated with this type of pollutant. Importantly, different dismantling methods were associated with distinct soil environmental factors, and their correlations with microplastic-associated microorganisms also varied.

Qualitative analysis of a class of SISM epidemic model influenced by media publicity.

Considering the influence of media lagging publicity on the awareness rate of epidemic situation, this paper introduces the accumulation of epidemic awareness variables, establishes the SISM infectious disease model influenced by media publicity, and gives the sufficient conditions for the global asymptotic stability of the model disease-free equilibrium, the stability of the endemic disease equilibrium and the existence of the Hopf bifurcation. The variation trend of different effects of delayed media publicity on the outbreak is simulated. Based on the data of A (H1N1), the interference degree of the parameters in the model is analyzed. The results show that shortening the lag time of the media report and increasing the implementation rate and the transfer rate of media propaganda can effectively control the epidemic and gradually end the epidemic.

System Prediction and Validation of TCM for Chronic Myeloid Leukemia Treatment from the Perspective of Low-Toxicity Chemotherapy: A Stilbene α-Viniferin Has a Proapoptotic Effect on K562 Cells via the Mitochondrial Pathway.

OBJECTIVE: In traditional Chinese medicine (TCM), chronic myeloid leukemia (CML) has been attributed to "poisoned bone marrow," which is viewed as a loss of Qi or blood, a deficiency in Yin or Yang that causes a complex imbalance between cell growth and death. Malignant myeloid progenitor cells display excessive growth that is difficult to control without toxicity. More than 60 herbs in TCM have shown efficacy against CML. However, the key molecules and mechanisms involved in the holistic-level characterization, as well as the effective target associations, are still unknown. METHODS: The present study employed a computational approach with filtering potential compounds via admetSAR, systems biology-based functional data prediction, and biochemical and molecular biological validation. RESULTS: We generated 118 bioactive compounds from 11 herbs within four dialectical therapy groups that are most commonly used to treat CML and predicted 141 potential targets. The stilbene resveratrol and its derivatives were found to be highly related to these targets. Among them, α-viniferin was predicted to target Bcl-2, caspase-3, 8, and 9, MAPK14, CDK2, HSP90AA1, and others, reflecting CML therapeutic strategies. In vitro, experimental data showed a nonnecrotic growth limitation of K562 cells caused by α-viniferin was predicted to target Bcl-2, caspase-3, 8, and 9, MAPK14, CDK2, HSP90AA1, and others, reflecting CML therapeutic strategies. µg·mL-1 at 24 h. Finally, we validated the chemotherapeutic effect of α-viniferin was predicted to target Bcl-2, caspase-3, 8, and 9, MAPK14, CDK2, HSP90AA1, and others, reflecting CML therapeutic strategies. CONCLUSIONS: Our work sheds light on the mechanism of the efficacy of the stilbene α-viniferin in TCM for the prevention of CML. This work also predicts and validates targets in the mitochondrial signaling pathway, providing a novel strategy for CML treatment.α-viniferin was predicted to target Bcl-2, caspase-3, 8, and 9, MAPK14, CDK2, HSP90AA1, and others, reflecting CML therapeutic strategies.

Spectroscopic studies of solutes in aqueous solution.

Absorption and fluorescence characteristics of aqueous solutions of salts, sugars, and amino acids were studied using UV-vis spectroscopy and spectrofluorometry. Motivation stemmed from unanticipated absorption spectral and fluorescence features of the "exclusion zone" seen adjacent to various hydrophilic surfaces. Those features implied a structure distinct from that of bulk water (Adv. Colloid Interface Sci. 2006, 127, 19). Absorption peaks at approximately 270 nm similar to those observed in the exclusion zone were seen in solutions of the following substances: salts, Nafion 117 solution/film, l-lysine, d-alanine, d-glucose and sucrose. To determine the fate of the absorbed energy, we studied the fluorescence properties of these solutions. The salts showed fluorescence emission around 480-490 nm under different excitation wavelengths. The fluorescence intensity of LiCl was higher than NaCl, which was in turn higher than KCl-the same ordering as the absorption intensities. Fluorescence of Nafion 117 solution/film, l-lysine, d-alanine, d-glucose and sucrose were observed as well, with multiple excitation wavelengths. Hence, at least some of the absorbed energy is released as fluorescence. The results show features closely similar to those observed in the exclusion zone, implying that the aqueous region around the solutes resembles the aqueous zone adjacent to hydrophilic surfaces. Both may be more extensively ordered than previously thought.

Ambient fine particulate pollution and daily morbidity of stroke in Chengdu, China.

INTRODUCTION: Association has been reported between ambient fine particulate matter (PM) and adverse outcomes of cerebrovascular events. However, it remains unclear that whether short-term exposure to PM relates to stroke and the lag of health effects. This triggers us to examine the relationship between PM and population stroke morbidity in Chengdu. METHODS: The daily average concentration of atmospheric pollutants and meteorological factors and daily morbidity of stroke in Chengdu (2013-2015) were collected. Based on time series analysis-generalized additive models (GAM), single-pollutant, two-pollutant and multi-pollutant model were established. The effects of atmospheric PM2.5 (defined as PM less than 2.5µm in aerodynamic diameter), PMc(defined as PM less than 10µm and more than 2.5µm in aerodynamic diameter) and PM10 (defined as PM less than 10µm in aerodynamic diameter) concentration on the daily mortality of stroke were analyzed, respectively. RESULTS: The three-year mean concentrations of PM2.5, PMc and PM10 for air pollutants were 75.9, 43.9 and 119.7 µg/m3, respectively. PM2.5 on the current day (lag0) and with a moving average of 0-1 days were significantly associated with the increasing risk of stroke morbidity, and PM2.5 with a lag of 0-1 days had greater association, whereas for PMc and PM10 there were no significant association observed. In our study, every 10µg/m3 increase of PM2.5 was associated with 0.69% percent change in stroke morbidity (95%CI: 0.01~1.38). For females, every 10µg/m3 increase of PM2.5 contributes to 0.80% percent change of onset. And for the group of age less than 65, we observed 0.78% higher risk every 10µg/m3 increase of PM2.5. CONCLUSIONS: These findings suggest that short-term exposure to PM2.5 within 1 day is associated with the onset of stroke, and the younger people (age<65) and females are more sensitive than older people and males.

Transgenic Mice Overexpressing the Divalent Metal Transporter 1 Exhibit Iron Accumulation and Enhanced Parkin Expression in the Brain.

Exposure to divalent metals such as iron and manganese is thought to increase the risk for Parkinson's disease (PD). Under normal circumstances, cellular iron and manganese uptake is regulated by the divalent metal transporter 1 (DMT1). Accordingly, alterations in DMT1 levels may underlie the abnormal accumulation of metal ions and thereby disease pathogenesis. Here, we have generated transgenic mice overexpressing DMT1 under the direction of a mouse prion promoter and demonstrated its robust expression in several regions of the brain. When fed with iron-supplemented diet, DMT1-expressing mice exhibit rather selective accumulation of iron in the substantia nigra, which is the principal region affected in human PD cases, but otherwise appear normal. Alongside this, the expression of Parkin is also enhanced, likely as a neuroprotective response, which may explain the lack of phenotype in these mice. When DMT1 is overexpressed against a Parkin null background, the double-mutant mice similarly resisted a disease phenotype even when fed with iron- or manganese-supplemented diet. However, these mice exhibit greater vulnerability toward 6-hydroxydopamine-induced neurotoxicity. Taken together, our results suggest that iron accumulation alone is not sufficient to cause neurodegeneration and that multiple hits are required to promote PD.

Synthesis and antifeedant activity of new oxadiazolyl 3(2H)-pyridazinones.

A total of 20 new compounds containing the oxadiazolyl 3(2H)-pyridazinone moiety were synthesized. The structures of all the compounds were confirmed by (1)H NMR, IR, MS, and elemental analysis. Their insect antifeedant activities against Asiatic corn borer Ostrinia furnacalis (Guenee) were examined and compared with commercial azadirachtin. The compounds exhibited significant levels of activity. The feeding deterrency values of IIIa,j were 57% and 51% at 500 mg/kg concentration, respectively.