Repeated transcranial magnetic stimulation (rTMS) is one of the commonly used brain stimulation techniques. In order to investigate the effects of rTMS on the excitability of different types of neurons, this study is conducted to investigate the effects of rTMS on the cognitive function of mice and the excitability of hippocampal glutaminergic neurons and gamma-aminobutyric neurons from the perspective of electrophysiology. In this study, mice were randomly divided into glutaminergic control group, glutaminergic magnetic stimulation group, gamma-aminobutyric acid energy control group, and gamma-aminobutyric acid magnetic stimulation group. The four groups of mice were injected with adeno-associated virus to label two types of neurons and were implanted optical fiber. The stimulation groups received 14 days of stimulation and the control groups received 14 days of pseudo-stimulation. The fluorescence intensity of calcium ions in mice was recorded by optical fiber system. Behavioral experiments were conducted to explore the changes of cognitive function in mice. The patch-clamp system was used to detect the changes of neuronal action potential characteristics. The results showed that rTMS significantly improved the cognitive function of mice, increased the amplitude of calcium fluorescence of glutamergic neurons and gamma-aminobutyric neurons in the hippocampus, and enhanced the action potential related indexes of glutamergic neurons and gamma-aminobutyric neurons. The results suggest that rTMS can improve the cognitive ability of mice by enhancing the excitability of hippocampal glutaminergic neurons and gamma-aminobutyric neurons.
Animals ; Mice ; Hippocampus/cytology* ; Transcranial Magnetic Stimulation ; Neurons/physiology* ; Male ; Cognition/physiology* ; gamma-Aminobutyric Acid/metabolism* ; Action Potentials/physiology*

ObjectiveIn recent years, the negative impact of microgravity on astronauts’ nervous systems has received widespread attention. The repetitive transcranial magnetic stimulation (rTMS) technology has shown significant positive effects in the treatment of neurological and psychiatric disorders. The potential benefits of combined frequency stimulation (CFS) which combines different frequency stimulation patterns in ameliorating neurological dysfunctions induced by the microgravity environment, still require in-depth investigation. Exploring the therapeutic effects and electrophysiological mechanisms of CFS in improving various neurological disorders caused by microgravity holds significant importance for neuroscience and the clinical application of magnetic stimulation. MethodsThis study employed 40 C57BL/6 mice, randomly divided into 5 groups: sham group, hindlimb unloading (HU) group, 10 Hz group, 20 Hz group, and combined frequency stimulation (10 Hz+20 Hz, CFS) group. Mice in all groups except the sham group received 14 d of simulated microgravity conditions along with 14 d of repetitive transcranial magnetic stimulation. The effects of CFS on negative emotions and spatial cognitive abilities were assessed through sucrose preference tests and water maze experiments. Finally, patch-clamp techniques were used to record action potentials, resting membrane potentials, and ion channel dynamics of granule neurons in the hippocampal dentate gyrus (DG) region. ResultsCompared to the single-frequency stimulation group, behavioral results indicated that the combined frequency stimulation (10 Hz+20 Hz) significantly improved cognitive impairments and negative emotions in simulated microgravity mice. Electrophysiological experiments revealed a decrease in excitability of granule neurons in the hippocampal DG region after HU manipulation, whereas the combined frequency stimulation notably enhanced neuronal excitability and improved the dynamic characteristics of voltage-gated Na⁺ and K⁺ channels. ConclusionThe repetitive transcranial magnetic stimulation with combined frequencies (10 Hz+20 Hz) effectively ameliorates cognitive impairments and negative emotions in simulated microgravity mice. This improvement is likely attributed to the influence of combined frequency stimulation on neuronal excitability and the dynamic characteristics of Na⁺ and K⁺ channels. Consequently, this study holds the promise to provide a theoretical basis for alleviating cognitive and emotional disorders induced by microgravity environments.

This paper aimed to study the chemical constituents from the root bark of Schisandra sphenanthera. Silica, Sephadex LH-20 and RP-HPLC were used to separate and purify the 80% ethanol extract of S. sphenanthera. Eleven compounds were identified by ~1H-NMR, ~(13)C-NMR, ESI-MS, etc., which were 2-[2-hydroxy-5-(3-hydroxypropyl)-3-methoxyphenyl]-propane-1,3-diol(1), threo-7-methoxyguaiacylglycerol(2),4-O-(2-hydroxy-1-hydroxymethylethyl)-dihydroconiferylalcohol(3), morusin(4), sanggenol A(5), sanggenon I(6), sanggenon N(7), leachianone G(8),(+)-catechin(9), epicatechin(10), and 7,4'-dimethoxyisoflavone(11). Among them, compound 1 was a new compound, and compounds 2-9 were isolated from S. sphenanthera for the first time. Compounds 2-11 were subjected to cell viability assay, and the results revealed that compounds 4 and 5 had potential cytotoxicity, and compound 4 also had potential antiviral activity.
Schisandra ; Plant Bark ; Antiviral Agents ; Biological Assay ; Catechin ; Phenols

The chemical constituents of Helleborus thibetanus were isolated and purified by silica gel column chromatography, Sephadex LH-20 gel column chromatography, and semi-preparative RP-HPLC, and the structures of all compounds were identified by modern spectrographic technology(MS, NMR). The MTT method was used to measure the cytotoxicity of compounds 1-8. Twelve compounds were isolated from the roots and rhizomes of H. thibetanus and were identified as(25R)-22β,25-expoxy-26-[(O-β-D-glucopyranosyl)oxy]-1β,3β-dihydroxyfurosta-5-en(1), β-sitosterol myristate(2), β-sitosterol lactate(3), β-sitosterol 3-O-β-D-glucopyrannoside(4), 4,6,8-trihydroxy-3,4-dihydronaphthalen-1(2H)-one(5), 1,3,5-trimethoxybenzene(6), 7,8-dimethylbenzo pteridine-2,4(1H,3H)-dione(7), 1H-indole-3-carboxylic acid(8), p-hydroxy cinnamic acid(9), lauric acid(10), n-butyl α-L-arabinofuranoside(11) and methyl-α-D-fructofuranoside(12), respectively. Among them, compound 1 is a new compound and named thibetanoside L; compounds 2, 5-8, 11 are first isolated from the family Ranunculaceae; compound 12 is isolated from the genus Helleborus for the first time. The results of MTT assay showed that the IC_(50) values of compounds 1-8 against HepG2 and HCT116 cells were greater than 100 μmol·L~(-1).
Helleborus/chemistry* ; Molecular Structure ; Plant Roots/chemistry* ; Rhizome/chemistry* ; Magnetic Resonance Spectroscopy

Complicated chemical reactions occur in the decoction of traditional Chinese medicines(TCMs) which features complex components, influencing the safety, efficacy, and quality controllability of TCMs. Therefore, it is particularly important to clarify the chemical reaction mechanism of TCMs in the decoction. This study summarized eight typical chemical reactions in the decoction of TCMs, such as substitution reaction, redox reaction, isomerization/stereoselective reaction, complexation, and supramolecular reaction. With the "toxicity attenuation and efficiency enhancement" of aconitines and other examples, this study reviewed the reactions in decoction of TCMs, which was expected to clarify the variation mechanisms of key chemical components in this process and to help guide medicine preparation and safe and rational use of medicine in clinical settings. The current main research methods for chemical reaction mechanisms of decoction of TCMs were also summed up and compared. The novel real-time analysis device of decoction system for TCMs was found to be efficient and simple without the pre-treatment of samples. This device provides a promising solution, which has great potential in quantity evaluation and control of TCMs. Moreover, it is expected to become a foundational and exemplary research tool, which can advance the research in this field.
Medicine ; Medicine, Chinese Traditional ; Research Design

Carcinoma ; Humans ; Limbic Encephalitis ; diagnosis ; surgery ; Male ; Middle Aged ; Nasopharyngeal Neoplasms ; diagnosis ; surgery

This study was aimed to investigate the effect of sodium valproate(VPA) on human myelodysplastic syndrome cell line SKM-1 and its mechanism. The cell proliferation was determined by MTT assay, cell apoptosis was analyzed by flow cytometry. The expressions of c-flipl, c-flips and dlk1 mRNA were detected by RT-PCR. The results showed that VPA could inhibited the growth of SKM-1 cells in dose- and time-dependent manners. The flow cytometric analysis indicated that VPA could induce cell apoptosis, apoptosis rate increased in dose-dependent manner. The expressions of c-flipl, c-flips and dlk1 mRNA in SKM-1 cell treated with VPA decreased using of VPA. It is concluded that VPA can induce apoptosis and inhibited proliferation of SKM-1 cells. In this process, the decreasing of c-flipl, c-flips and dlk1 mRNA expression may play important roles.
Apoptosis ; drug effects ; CASP8 and FADD-Like Apoptosis Regulating Protein ; metabolism ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Humans ; Intercellular Signaling Peptides and Proteins ; metabolism ; Membrane Proteins ; metabolism ; Myelodysplastic Syndromes ; metabolism ; pathology ; RNA, Messenger ; metabolism ; Valproic Acid ; pharmacology

This study was aimed to explore the potential therapy of Gambogic acid (GA) combined with magnetic nanoparticle of Fe3O4 (Fe3O4-MNP) on leukemia. The proliferation of U937 cells and the cytotoxicity were evaluated by MTT assay. Cell apoptosis was observed and analyzed by microscopy and flow cytometry respectively. The expressions of gene and protein were detected by quantitative real-time polymerase chain reaction and Western blot respectively. The results showed that GA enhanced the cytotoxicity for U937 cells in dose- and time-dependent manners. The Fe3O4-MNP itself had not cytotoxicity, but could enhance the inhibitory effect of GA on proliferation of U937 cells. The apoptotic rate of U937 cells induced by combination of GA with Fe3O4-MNP was higher than that by GA alone. The typical apoptotic features of cells treated with GA and Fe3O4-MNP were observed. The expression levels of caspase-3 and bax after co-treatment of GA and Fe3O4-MNP were higher than that exposed to GA or Fe3O4-MNP alone, but the expressions of bcl-2, NF-kappaB and survivin were down-regulated. It is concluded that Fe3O4-MNP can promote GA-induced apoptosis in U937 cells, and the combination of GA with Fe3O4-MNP may be a safer and less toxic new therapy for leukemia.
Apoptosis ; drug effects ; Humans ; Iron Compounds ; administration & dosage ; pharmacology ; Magnetics ; Nanoparticles ; U937 Cells ; Xanthones ; pharmacology

OBJECTIVETo investigate the effect of iron on the growth, physiology and photosynthesis of cyanobacteria.

METHODSA gradient of iron concentrations was employed to investigate the growth, photo-pigments (chlorophyll A and phycocyanin), and cell chemical contents (C, N, P) of Microcystis aeruginosa in response to different iron additions.

RESULTSThe specific growth rate during the exponential growth phase, as well as the cell chlorophyll A and the phycocyanin content, was limited by iron below 12.3 tmol Fe x L(-1). The growth was inhibited when the iron concentration was at 24.6 micromol Fe x L(-1). The cell chlorophyll A and the phycocyanin content were saturated when the iron concentration was above 12.3 micromol Fe x L(-1) and declined slightly at 24.6 micromol Fe x L(-1). At a low iron concentration (about 6.15 micromol Fe x L(-1) and less), the cell nitrogen and carbohydrate content were iron limited, and the variation of the cell phosphorus content was similar to that of the nitrogen and carbohydrate, with a transition point of 12.3 micromol Fe x L(-1).

CONCLUSIONThe variation of cynobacteria growth is synchronous with that of the photo-pigments or the cell chemical content, and there exist relationships among photosynthesis, growth and internal chemical content, which could be useful for the growth estimation from the cell characteristics.

Carbohydrates ; analysis ; Culture Media ; chemistry ; Dose-Response Relationship, Drug ; Iron ; pharmacology ; Microcystis ; chemistry ; cytology ; drug effects ; physiology ; Nitrogen ; analysis ; Phosphorus ; analysis