In vitro evidence of baicalein’s inhibition of the metabolism of zidovudine (AZT)

Background: Herb-drug interaction (HDI) has been regarded as a key factor limiting the clinical application of herbs and drugs. Aims: Potential baicalein-zidovudine (AZT) interaction was predicted in the present study. Methods: In vitro evaluation of baicalein’s inhibition towards human liver microsomes (HLMs)-catalyzed metabolism of zidovudine (AZT) was performed. Dixon and Lineweaver-Burk plots were used to determine the inhibition kinetic type, and second plot with the slopes from Lineweaver-Burk plot versus the concentrations of baicalein was employed to calculate the inhibition parameter (Ki). In combination with the in vivo concentration of baicalein, in vitro-in vivo extrapolation (IVIVE) was carried out to predict in vivo baicalein-AZT interaction. Results: Competitive inhibition of baicalein towards AZT metabolism was demonstrated, and the Ki value was calculated to be 101.2 μM. The value of AUCi/AUC was calculated to be 2. Conclusion: Potential baicalein-AZT interaction was indicated in the present study, indicating the need for monitoring when AZT is co-administrated with baicalein or baicalein-containing herbs.Keywords: Baicalein, zidovudine (AZT), metabolism, herb-drug interactionAfrican Health sciences Vol 14 No. 1 March 201

Plant toxin β-ODAP activates integrin β1 and focal adhesion : a critical pathway to cause neurolathyrism

Neurolathyrism is a unique neurodegeneration disease caused by beta-N-oxalyl-L-alpha, beta-diaminopropionic (beta-ODAP) present in grass pea seed (Lathyrus stativus L.) and its pathogenetic mechanism is unclear. This issue has become a critical restriction to take full advantage of drought-tolerant grass pea as an elite germplasm resource under climate change. We found that, in a human glioma cell line, beta-ODAP treatment decreased mitochondrial membrane potential, leading to outside release and overfall of Ca2+ from mitochondria to cellular matrix. Increased Ca2+ in cellular matrix activated the pathway of ECM, and brought about the overexpression of beta 1 integrin on cytomembrane surface and the phosphorylation of focal adhesion kinase (FAK). The formation of high concentration of FA units on the cell microfilaments further induced overexpression of paxillin, and then inhibited cytoskeleton polymerization. This phenomenon turned to cause serious cell microfilaments distortion and ultimately cytoskeleton collapse. We also conducted qRT-PCR verification on RNA-sequence data using 8 randomly chosen genes of pathway enrichment, and confirmed that the data was statistically reliable. For the first time, we proposed a relatively complete signal pathway to neurolathyrism. This work would help open a new window to cure neurolathyrism, and fully utilize grass pea germplasm resource under climate change

Rapid Surface Oxidation as a Source of Surface Degradation Factor for Bi2Se3

Bi2Se3 is a topological insulator with metallic surface states residing in a large bulk bandgap. It is believed that Bi2Se3 gets additional n-type doping after exposure to atmosphere, thereby reducing the relative contribution of surface states in total conductivity. In this letter, transport measurements on Bi2Se3 nanoribbons provide additional evidence of such environmental doping process. Systematic surface composition analyses by X-ray photoelectron spectroscopy reveal fast formation and continuous growth of native oxide on Bi2Se3 under ambient conditions. In addition to n-type doping at the surface, such surface oxidation is likely the material origin of the degradation of topological surface states. Appropriate surface passivation or encapsulation may be required to probe topological surface states of Bi2Se3 by transport measurements

The LAMOST Complete Spectroscopic Survey of Pointing Area (LaCoSSPAr) in the Southern Galactic Cap I. The Spectroscopic Redshift Catalog

We present a spectroscopic redshift catalog from the LAMOST Complete Spectroscopic Survey of Pointing Area (LaCoSSPAr) in the Southern Galactic Cap (SGC), which is designed to observe all sources (Galactic and extra-galactic) by using repeating observations with a limiting magnitude of $r=18.1~mag$ in two $20~deg^2$ fields. The project is mainly focusing on the completeness of LAMOST ExtraGAlactic Surveys (LEGAS) in the SGC, the deficiencies of source selection methods and the basic performance parameters of LAMOST telescope. In both fields, more than 95% of galaxies have been observed. A post-processing has been applied to LAMOST 1D spectrum to remove the majority of remaining sky background residuals. More than 10,000 spectra have been visually inspected to measure the redshift by using combinations of different emission/absorption features with uncertainty of $\sigma_{z}/(1+z)<0.001$. In total, there are 1528 redshifts (623 absorption and 905 emission line galaxies) in Field A and 1570 redshifts (569 absorption and 1001 emission line galaxies) in Field B have been measured. The results show that it is possible to derive redshift from low SNR galaxies with our post-processing and visual inspection. Our analysis also indicates that up to 1/4 of the input targets for a typical extra-galactic spectroscopic survey might be unreliable. The multi-wavelength data analysis shows that the majority of mid-infrared-detected absorption (91.3%) and emission line galaxies (93.3%) can be well separated by an empirical criterion of $W2-W3=2.4$. Meanwhile, a fainter sequence paralleled to the main population of galaxies has been witnessed both in $M_r$/$W2-W3$ and $M_*$/$W2-W3$ diagrams, which could be the population of luminous dwarf galaxies but contaminated by the edge-on/highly inclined galaxies ($\sim30\%$).Comment: 19 pages, 14 figures, 2 MRT, accepted by ApJ

Long-term environmental enrichment overcomes depression, learning, and memory impairment in elderly CD-1 mice with maternal sleep deprivation exposure

Early-life stress disrupts central nervous system development and increases the risk of neuropsychiatric disorder in offspring based on rodent studies. Maternal sleep deprivation (MSD) in rodents has also been associated with depression and cognitive decline in adult offspring. However, it is not known whether these issues persist into old age. Environmental enrichment is a non-pharmacological intervention with proven benefits in improving depression and cognitive impairment; however, it is unclear whether these benefits hold for aging mice following MSD exposure. The aim of this study was to explore the effects of MSD on depression and cognition in elderly offspring CD-1 mice and to determine whether long-term environmental enrichment could alleviate these effects by improving neuroinflammation and synaptic plasticity. The offspring mice subjected to MSD were randomly assigned to either a standard environment or an enriched environment. At 18 months of age, the forced swimming and tail suspension tests were used to evaluated depression-like behaviors, and the Morris water maze test was used to evaluate cognitive function. The expression levels of hippocampal proinflammatory cytokines and synaptic plasticity-associated proteins were also measured. MSD increased depression-like behaviors and impaired cognition function in aging CD-1 offspring mice. These effects were accompanied by upregulated interleukin (IL)-1β, IL-6, and tumor necrosis factor-α expression, and downregulated brain-derived neurotrophic factor, tyrosine kinase receptor B, postsynaptic density-95, and synaptophysin expression in the hippocampus. All of these changes were reversed by long-term exposure to an enriched environment. These findings suggest that MSD exerts long-term effects on the behaviors of offspring in mice, leading to depression and cognitive impairment in older age. Importantly, long-term environmental enrichment could counteract the behavior difficulties induced by MSD through improving hippocampal proinflammatory cytokines and synaptic plasticity-associated proteins

Resveratrol ameliorates maternal immune activation-associated cognitive impairment in adult male offspring by relieving inflammation and improving synaptic dysfunction

Maternal exposure to inflammation may represent a major risk factor for neuropsychiatric disorders with associated cognitive dysfunction in offspring in later life. Growing evidence has suggested that resveratrol exerts a beneficial effect on cognitive impairment via its anti-inflammatory and antioxidant properties and by ameliorating synaptic dysfunction. However, how resveratrol affects maternal immune activation-induced cognitive dysfunction and the underlying mechanisms are unclear. In the present study, pregnant dams were given an intraperitoneal injection of lipopolysaccharide (LPS; 50 μg/kg) on gestational day 15. Subsequently, the offspring mice were treated or not with resveratrol (40 mg/kg) from postnatal day (PND) 60 to PND 88. Male offspring were selected for the evaluation of cognitive function using the Morris water maze test. The hippocampal levels of pro-inflammatory cytokines were examined by ELISA. The mRNA and protein levels of sirtuin-1 (SIRT1), brain-derived neurotrophic factor (BDNF), postsynaptic density protein 95 (PSD-95), and synaptophysin (SYP) were determined by RT-qPCR and western blot, respectively. The results showed that male offspring mice exposed to LPS in utero exhibited learning and memory impairment. Additionally, the levels of interleukin (IL)-1β, IL-6, and tumor necrosis factor-alpha (TNF-α) were increased while those of SIRT1, BDNF, PSD-95, and SYP were decreased in male offspring of LPS-treated mothers. Treatment with resveratrol reversed cognitive impairment and attenuated the increase in the levels of pro-inflammatory cytokines induced by maternal immune activation in the offspring mice. Furthermore, resveratrol reversed the deleterious effects of maternal immune activation on SIRT1, BDNF, PSD-95, and SYP levels in the hippocampus. Collectively, our results suggested that resveratrol can effectively improve learning and memory impairment induced by maternal immune activation via the modulation of inflammation and synaptic dysfunction