[Lycium barbarum miR2911-loaded exosomes promote spermatogenic function recovery in rats with non-obstructive azoospermia by regulating Wnt/ß-catenin signaling pathways].

OBJECTIVE: To investigate the effect of exosomes loaded with Lycium barbarum miRNA (Lb-miR2911) on spermatogenic function recovery in non-obstructive azoospermia (NOA) rats through cross-regulation of the Wnt/ß-catenin signaling pathways. METHODS: We established an NOA model in 30 four-week-old male SD rats by intraperitoneal injection of busulfan. At 5 weeks after modeling, we equally randomized the rats into a model control group (MC，untreated), an Lb-miR2911EXO group (Lb-miR2911EXO ，treated by intratesticular injection of Lb-miR2911-loaded exosomes), and a sham group (Shame，treated by intratesticular injection of exosomes-empty drug), with another 10 male SD rats taken as normal controls（NC）. We observed the uptake and metabolic changes of Lb-miR2911 in the testis tissue of the rats by RNA FISH at 2 and 6 weeks after treatment, detected cell proliferation, spermatogenesis and gene expressions of the Wnt/ß-catenin signaling pathways in the testis tissue by Transcriptome sequencing analysis combined with Western blot and RT-PCR at 12 weeks, evaluated the recovery of the spermatogenic function based on the testis tissue morphology and sperm quality, and assessed the organ toxicity of Lb-miR2911 in the tissue and organs of the rats based on histomorphological analysis and the levels of serum TNF-α, IL-1ß, Aspartate aminotransferase (AST), Alanine aminotransferase (ALT) and other relevant indicators. RESULTS: After 12 weeks of treatment, histomorphological analysis showed regular arrangement of spermatogenic cells at all levels in the testis tissue, with a large number of mature sperm in the tubular lumen, and with significantly higher Johnsen scores, testis weight, testicular index, sperm concentration and sperm motility in the Lb-miR2911EXO than in the sham group (all P< 0.05). Compared with the model controls, the Lb-miR2911EXO group exhibited remarkably down-regulated gene expression of DACT3 (P< 0.05), up-regulated expressions of DVL2 and ß-catenin (P< 0.05), elevated levels of p-DVL2 and ß-catenin (nucleus) proteins (P< 0.05), increased expressions of cell proliferation-related genes CCND1, CCNE1 and CCNE2 (P< 0.05) and spermatogenesis-related genes DMC1, CCR6, JAM2 and KLC3 (P< 0.05). No pathological changes were observed in the lung, liver and kidney tissues of the rats, or in the levels of serum TNF-α, IL-1ß, AST, ALT, creatinine and urea nitrogen in the rats treated with Lb-miR2911EXO compared with the normal controls (P > 0.05). CONCLUSION: Lb-miR2911-loaded exosomes promote spermatogenic function recovery in NOA rats through cross-regulation of the DACT3, Wnt and ß-catenin signaling pathways.

A feasible strategy based on isotopic fine structures to enhance the reliability of metabolite identification by Fourier transform ion cyclotron resonance mass spectrometry.

RATIONALE: In the process of the identification of unknown metabolites, the most important thing is to determine their real chemical formulae according to the accurate masses which are determined by high-resolution mass spectrometry. However, high mass accuracy alone is not enough to exclude false candidates. Use of isotopic fine structures (IFSs) derived from Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) as a single further constraint could decisively determine the molecular formulae for unknown metabolites. METHODS: Gastrodin, an active constituent from Gastrodia elata Bl., which can penetrate through the blood-brain barrier and rapidly decompose to p-hydroxybenzyl alcohol in the brain, was selected as a model drug. The accurate masses, possible chemical formulae and IFSs of its metabolites in rat plasma were acquired using FT-ICR MS. RESULTS: Besides gastrodin, a total of eight metabolites including two phase I and six phase II metabolites were detected. Their chemical formulae were decisively determined by IFSs. Furthermore, their chemical structures were identified by comparing their fragment ions with those of gastrodin. Results indicated the metabolic pathways of gastrodin in rats including deglycosylation, oxidation, glucuronidation, sulfate conjugation and glycine conjugation. CONCLUSIONS: It is demonstrated that IFSs are effective in unambiguous determination of chemical formulae of metabolites. It could be used as a feasible strategy to enhance the reliability of metabolite identification in drug metabolism studies.

[Study on the mechanism of Flos Puerariae and Semen Hoveniae in treatment of alcoholic liver injury based on network pharmacology and molecular docking].

OBJECTIVE: To explore the mechanism of Flos Puerariae and Semen Hoveniae in treatment of alcoholic liver injury (ALI) based on network pharmacology and molecular docking. METHODS: The information of chemical constituents and targets of Flos Puerariae and Semen Hoveniae was collected from TCMSP and Swiss databases, and the threshold values of oral bioavailability (OB) ≥ 30%, drug likeness (DL) ≥0.18 were used to screen the potential active compounds. The GeneCard and DrugBank databases were used to obtain the targets corresponding to ALI. The common targets were queried using Venn Diagram, and the network of PPI and Gene Ontology (GO) functional enrichment analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis were performed through DAVID and Reactome database. Autodock Vina software was used for molecular docking of potential ingredients and key targets. RESULTS: A total of 21 potential active compounds and 431 therapeutic targets were gathered in Flos Puerariae and Semen Hoveniae, which involved 273 biological functions, 90 KEGG pathways and 362 Reactome pathways. The GO functions involved protein binding, ATP binding, etc.; the KEGG pathways mainly included PI3K-Akt signaling pathway and TNF signaling pathway; the Reactome pathways contained signal transduction and immune system, etc. The results of molecular docking showed that 21 potential active ingredients had good affinity with the core targets Akt1, TP53 and IL-6. CONCLUSIONS: The network pharmacology and molecular docking analysis demonstrate the synergetic effect of Flos Puerariae and Semen Hoveniae with multi-compounds, multi-targets and multi-pathways in the treatment of ALI; and also predict the possible medicinal substance, key targets and pathways, which provides clues for the new drug development and mechanism research.

Metabolic profile of Kudiezi injection in rats by UHPLC coupled with Fourier transform ion cyclotron resonance mass spectrometry.

In this study, a reliable and sensitive ultra-high performance liquid chromatography coupled with fourier transform ion cyclotron resonance mass spectrometry method was developed for the systematic study of the metabolic profile of Kudiezi injection in rat plasma, bile, urine, and feces after intravenous administration of a single dose. The chromatographic separation was performed on an Agilent Eclipse Plus C18 column (4.6 mm × 50 mm, 1.8 µm) and the identification of prototype components and metabolites was achieved on a Bruker Solarix 7.0 T ultra-high resolution spectrometer in negative ion mode. Results indicated that a total of 76 constituents including 29 prototype compounds and 47 metabolites (10 phase I metabolites and 37 phase II metabolites) were tentatively identified. And the metabolic pathways of these prototype compounds including hydroxylation, dehydrogenation, glucuronidation, and sulfate conjugation. In conclusion, the developed method with high resolution and sensitivity was effective for screening and identification of prototypes and metabolites of Kudiezi injection in vivo. Moreover, these results would provide significant information for further pharmacokinetic and pharmacological research of Kudiezi injection in vivo.

Metabolic profile of salidroside in rats using high-performance liquid chromatography combined with Fourier transform ion cyclotron resonance mass spectrometry.

A high-performance liquid chromatography coupled to Fourier transform ion cyclotron resonance mass spectrometry (HPLC-FT-ICR MS) method was developed to study the in vivo metabolism of salidroside for the first time. Plasma, urine, bile, and feces samples were collected from male rats after a single intragastric gavage of salidroside at a dose of 50 mg/kg. Besides the parent drug, a total of seven metabolites (three phase I and four phase II metabolites) were detected and tentatively identified by comparing their mass spectrometry profiles with those of salidroside. Results indicated that metabolic pathways of salidroside in male rats included hydroxylation, dehydrogenation, glucuronidation, and sulfate conjugation. Among them, glucuronidation and sulfate conjugation were the major metabolic reactions. And most important, the detection of the sulfation metabolite of p-tyrosol provides a clue for whether the deglycosylation of salidroside occurs in vivo after intragastric gavage. In summary, results obtained in this study may contribute to the better understanding of the safety and mechanism of action of salidroside.

Rapid characterization of the chemical constituents of Cortex Fraxini by homogenate extraction followed by UHPLC coupled with Fourier transform ion cyclotron resonance mass spectrometry and GC-MS.

Cortex Fraxini is an important traditional Chinese medicine. In this work, a rapid and reliable homogenate extraction method was applied for the fast extraction for Cortex Fraxini, and the method was optimized by response surface methodology. Ultra high performance liquid chromatography combined with Fourier transform ion cyclotron resonance mass spectrometry and gas chromatography with mass spectrometry were established for the separation and characterization of the constituents of Cortex Fraxini. Liquid chromatography separation was conducted on a C18 column (150 mm × 2.1 mm, 1.8 µm), and gas chromatography separation was performed on a capillary with a 5% phenyl-methylpolysiloxane stationary phase (30 m × 0.25 mm × 0.25 mm) by injection of silylated samples. According to the results, 33 chemical compounds were characterized by liquid chromatography with mass spectrometry, and 11 chemical compounds were characterized by gas chromatography with mass spectrometry, and coumarins were the major components characterized by both gas chromatography with mass spectrometry and liquid chromatography with mass spectrometry. The proposed homogenate extraction was an efficient and rapid method, and coumarins, phenylethanoid glycosides, iridoid glycosides, phenylpropanoids, and lignans were the main constituents of Cortex Fraxini. This work laid the foundation for further study of Cortex Fraxini and will be helpful for the rapid extraction and characterization of ingredients in other traditional Chinese medicines.

Effect of liquid-to-solid lipid ratio on characterizations of flurbiprofen-loaded solid lipid nanoparticles (SLNs) and nanostructured lipid carriers (NLCs) for transdermal administration.

The aim of this study is to evaluate the effect of liquid-to-solid lipid ratio on properties of flurbiprofen-loaded solid lipid nanoparticles (SLNs) and nanostructured lipid carriers (NLCs), and to clarify the superiority of NLCs over SLNs for transdermal administration. Particle size, zeta potential, drug encapsulation efficiency, in vitro occlusion factor, differential scanning calorimetry, X-ray diffractometry, in vitro percutaneous permeation profile, and stability of SLNs and NLCs were compared. Particle size, zeta potential, drug encapsulation efficiency, in vitro occlusion factor, and in vitro percutaneous permeation amount of the developed NLCs were all <200 nm, < -20 mV, >78%, >35, and >240 µg/cm(2), respectively, however, for SLNs were 280 nm, -29.11 mV, 63.2%, 32.54, and 225.9 µg/cm(2), respectively. After 3 months storage at 4 °C and 25 °C, almost no significant differences between the evaluated parameters of NLCs were observed. However, for SLNs, particle size was increased to higher than 300 nm (4 °C and 25 °C), drug encapsulation efficiency was decreased to 51.2 (25 °C), in vitro occlusion factor was also decreased to lower than 25 (4 °C and 25 °C), and the cumulative amount was decreased to 148.9 µg/cm(2) (25 °C) and 184.4 µg/cm(2) (4 °C), respectively. And DSC and XRD studies indicated that not only the crystalline peaks of the encapsulated flurbiprofen disappeared but also obvious difference between samples and bulk Compritol® ATO 888 was seen. It could be concluded that liquid-to-solid lipid ratio has significant impact on the properties of SLNs and NLCs, and NLCs showed better stability than SLNs. Therefore, NLCs might be a better option than SLNs for transdermal administration.

Nanostructured lipid carriers-based flurbiprofen gel after topical administration: acute skin irritation, pharmacodynamics, and percutaneous absorption mechanism.

In order to assess the preliminary safety and effectiveness of nanostructured lipid carriers-based flurbiprofen gel (FP NLC-gel), the acute irritation test, in vivo pharmacodynamics evaluation and pharmacokinetic study were investigated after topical application. No dropsy and erythema were observed after continuous dosing 7 d of FP NLC-gel on the rabbit skin, and the xylene-induced ear drossy could be inhibited by FP NLC-gel at different dosages. The maximum concentration of FP in rats muscle was 2.03 µg/g and 1.55 µg/g after oral and topical administration, respectively. While the peak concentration in untreated muscle after topical administration was only 0.37 µg/mL. And at any time, following topical administration the mean muscle-plasma concentration ratio Cmuscle/CPlasma was obviously higher than that following oral administration. Results indicated that FP could directly penetrate into the subcutaneous muscle tissue from the administration site. Thus, the developed FP NLC-gel could be a safe and effective vehicle for topical delivery of FP.

Duration of television viewing and bone mineral density in Chinese women.

Studies on the relationship between television (TV) viewing and bone mineral density (BMD) in adults are limited. The purpose of this study was to examine whether longer duration of TV viewing increased the risk of lower BMD in Chinese women. A total of 626 female adults were voluntarily recruited into the study. Anthropometric measurements were obtained using standard procedures. Body composition including total body and regional BMD was estimated using dual-energy X-ray absorptiometry. The duration of TV viewing was categorized into 4 groups: <1 h, 1 to <2 h, 2 to <3 h, and ≥3 h. Multiple linear regression models were applied to analyze the associations between duration of TV viewing and total and regional BMD in all subjects and in subjects stratified by age of 45 years, respectively. After adjusting for age, BMI, alcohol use, smoking, education, income, urbanicity, leisure time physical activity, occupational physical activity, and menopause, the significant trend of pelvic BMD across categories of TV viewing was observed in all subjects (p < 0.05). Further analysis revealed that women aged <45 years, the 1 to <2 h group, the 2 to <3 h group, and the ≥3 h group were significantly associated with lower total body and regional BMD compared to women aged <45 years in the <1 h group. We concluded that the duration of TV viewing was negatively associated with BMD in Chinese women, especially in those aged 18-44 years. It might be sensible to reduce TV viewing time to prevent bone loss in young women.

Association of regional body fat with metabolic risks in Chinese women.

OBJECTIVE: To investigate the association of regional fat depots with metabolic risk factors in Chinese women. DESIGN: Total and regional fat depots including android fat and gynoid fat were measured by dual-energy X-ray absorptiometry. Central fat distribution was defined as android:gynoid fat ratio. Metabolic risk factors were defined as elevated TAG, reduced HDL-cholesterol, elevated blood pressure and elevated fasting plasma glucose. Logistic regression analyses were performed to examine the associations of regional fat depots with metabolic risk factors. The odds ratios of metabolic risks were further calculated according to tertiles of android fat and gynoid fat. SETTING: Participants were recruited from a community-based cross-sectional study. Face-to-face questionnaires, anthropometric and dual-energy X-ray absorptiometry measures were conducted. SUBJECTS: Chinese women (n 609) aged 18-79 years. RESULTS: Android fat and android:gynoid fat ratio were associated with significantly increased odds (OR = 1·4-3·7; P < 0·01) for almost all risk factors, whereas gynoid fat was independently associated with significantly decreased odds (OR = 0·3-0·6; P < 0·01). The inverse associations of gynoid fat with metabolic risk factors remained after adjusting for android fat. Even if their android fat level was in high, women in the highest tertile of gynoid fat had lower odds of having at least two metabolic risk factors compared with women in the lowest gynoid fat tertile (P for trend < 0·01). CONCLUSIONS: There were opposite associations of android and gynoid fat with metabolic risks in Chinese women. Gynoid fat rather than android fat might be a more important inclusion in metabolic disease risk evaluation in female Asians.

Two new indole-diterpenoids from the fungus Penicilliumcrustosum YN-HT-15.

Two new indole-diterpenoids named penijanthine B and penitrem H were isolated from the metabolites of the fungus Penicilliumcrustosum YN-HT-15, which was isolated from the red soil of Yunnan Province of China. The structures were determined on spectroscopic analyses and CD spectra.

Rapid Synthesis of Sb2Si2Te6 under High Pressure with a Modulated Microstructure.

Over the past decades, thermoelectric materials have advanced significantly, yet materials such as Sb2Si2Te6, which are challenging to synthesize chemically, often require lengthy and complex preparation processes, hindering their development. In this work, we prepare polycrystalline Sb2Si2Te6 bulk from elemental precursors using a high-pressure synthesis (HPS) method. This method offers significant advantages in efficiency and preparation duration. The applied pressure promotes an isotropic microstructure and regulates the thermoelectric properties by controlling precipitate contents, grain size, and twinning. Although an increase in thermal conductivity, mostly due to the notable increase in electrical conductivity, leads to less favorable thermal conductivity near room temperature compared to samples prepared using conventional methods, a beneficial reversal occurs at high temperatures. The polycrystalline Sb2Si2Te6 sample synthesized at 2 GPa demonstrates a peak ZT value of 1.1 at 773 K, outperforming most pristine Sb2Si2Te6 materials. This work demonstrates an efficient strategy for optimizing Sb2Si2Te6 performance and offers a new synthesis pathway for other challenging thermoelectric materials.

Enhanced Thermoelectric Performance of n-Type PbTe via Carrier Concentration Optimization over a Broad Temperature Range.

The optimal carrier concentration of thermoelectric materials increases with increasing temperature. However, conventional aliovalent doping usually provides an approximately constant carrier concentration over the whole temperature range, which can only match the optimal carrier concentration in a narrow temperature range. In this work, n-type indium and aluminum codoped PbTe were prepared with high-pressure synthesis, followed by spark plasma sintering. While Al doping can provide a roughly constant carrier concentration with varying temperatures, In doping can trap electrons at low temperatures and release them at high temperatures, thus optimizing the carrier concentration over a broad temperature range. As a result, both electrical transport properties and thermal conductivity are optimized, and a significantly enhanced thermoelectric performance is achieved in InxAl0.02Pb0.98Te. The optimal In0.008Al0.02Pb0.98Te shows a peak ZT of 1.3 and an average ZT of 1, with a decent conversion efficiency of 14%. Current work demonstrates that optimizing carrier concentration with varying temperatures is effective to enhance the thermoelectric performance of n-type PbTe.

Causes of death after hip fracture in senile patients.

Hip trauma has been a leading cause of death in senile patients for more than a centenary. Although the mortality decreased due to the advanced technique in medication, surgery and nursing, the increasing mortality should not be neglected in elders after orthopedic operation nowadays. Many factors are considered to influence the causes of death after trauma, such as age, gender, personal customs, comorbidities, types of fracture, timing of surgery, procedure, anesthesia, complications, medical treatment, activity of daily living, or even marriage status. This article reviews these causes from the aspects of patient's own factors, iatrogenic factors, medical treatment and other factors and provides some clues for further clinical application according to the recent foreign and domestic researches. According to the present research, it is essential for surgeons to perform a comprehensive estimation for patients suffering from hip trauma.

Cooperation between molecular targets of costimulation in promoting T cell persistence and tumor regression.

Costimulation regulates multiple cellular processes of T cells inducing proliferation, expansion, and survival. The molecular targets of costimulation might then be useful to augment T cell activities. Two defined targets of costimulatory signals in primary T cells are the anti-apoptotic bcl-2 family molecule Bcl-x(L), and survivin, an inhibitor of apoptosis family member that might regulate both cell division and survival. However, the relative importance of, and relationship between, these molecules in primary T cells is not clear. To understand whether they have overlapping or cooperative functions, we used retrovirus-mediated transduction to introduce Bcl-x(L) and survivin separately, or together linked by a 2A picornavirus self-cleaving peptide, into Ag-responding CD8(+) T cells. We found that CD8(+) effector T cells expressing both Bcl-x(L) and survivin strongly expanded at an early stage and had a long-term survival advantage over cells transduced with either molecule alone. In vivo, with response to tumor-expressed Ag following adoptive T cell transfer, Ag-reactive CD8(+) T cells expressing both Bcl-x(L) and survivin displayed greatly enhanced tumor protective activity compared with CD8(+) T cells expressing either molecule introduced separately. These results indicate that Bcl-x(L) and survivin can critically contribute in a cooperative, nonredundant manner to augment the accumulation and persistence of CD8(+) T cells following encounter with Ag. The data provide new insights into why costimulatory signals might need to be sustained over time and suggest a potential novel approach to augment cellular immunotherapy for cancer.

Autoimmune islet destruction in spontaneous type 1 diabetes is not beta-cell exclusive.

Pancreatic islets of Langerhans are enveloped by peri-islet Schwann cells (pSC), which express glial fibrillary acidic protein (GFAP) and S100beta. pSC-autoreactive T- and B-cell responses arise in 3- to 4-week-old diabetes-prone non-obese diabetic (NOD) mice, followed by progressive pSC destruction before detectable beta-cell death. Humans with probable prediabetes generate similar autoreactivities, and autoantibodies in islet-cell autoantibody (lCA) -positive sera co-localize to pSC. Moreover, GFAP-specific NOD T-cell lines transferred pathogenic peri-insulitis to NOD/severe combined immunodeficient (NOD/SCID) mice, and immunotherapy with GFAP or S100beta prevented diabetes. pSC survived in rat insulin promoter Iymphocytic choriomeningitis virus (rip-LCMV) glycoprotein/CD8+ T-cell receptor(gp) double-transgenic mice with virus-induced diabetes, suggesting that pSC death is not an obligate consequence of local inflammation and beta-cell destruction. However, pSC were deleted in spontaneously diabetic NOD mice carrying the CD8+/8.3 T-cell receptor transgene, a T cell receptor commonly expressed in earliest islet infiltrates. Autoimmune targeting of pancreatic nervous system tissue elements seems to be an integral, early part of natural type 1 diabetes.

AtWDS1 negatively regulates age-dependent and dark-induced leaf senescence in Arabidopsis.

Although the involvement of ROS (reactive oxygen species) in leaf senescence is well known, the factors governing this accumulation of ROS are not fully characterized. In this study, analysis of transgenic overexpressing and knock out lines of AtWDS1 (encoding a WD repeat protein), indicates that AtWDS1 negatively regulates age-dependent and dark-induced leaf senescence. Furthermore, we observed ROS accumulation and altered tolerance of oxidative stress in atwds1 plants, as well as upregulated expression of oxidative stress-responsive genes. The location of an EGFP-AtWDS1 fusion protein in the nucleus of transformed cells and plants indicates that AtWDS1 is a nuclear protein, and, using a Dual-Luciferase assay, we showed that AtWDS1 can act as a transcription activator. However, the lack of a nuclear localization sequence in AtWDS1 suggests that its presence in the nucleus must depend on interactions with other proteins. Indeed, we found that AtWDS1 interacts directly with AtRanBPM, and that mutation of the AtRanBPM gene results in partial mislocalization of AtWDS1 in the cytoplasm. Together, these results suggest a role for AtWDS1 as a novel modulator of redox homeostasis, which responds to developmental and stress signals to regulate leaf senescence.

An available strategy for elemental composition determination of organic impurities in commercial preparations based on accurate mass and peak ratio of isotopic fine structures (IFSs) by dual mode combined-FT-ICR-MS and fraction collection technology.

A strategy to determine the elemental composition of organic impurities in commercial preparations was established by combining high-performance liquid chromatography (HPLC)-Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) and fraction collector with direct infusion-FT-ICR-MS (DI-FT-ICR-MS). Under HPLC-FT-ICR-MS mode, all impurities in model sample were chromatographically separated and collected by fraction collector according to their retention time. The accurate mass of each impurity and their candidate formulae under 1 ppm mass tolerance were calculated. Subsequently, theoretical isotopic fine structures (IFSs) of the candidate formulae were generated. Furthermore, the collected fractions were tested and the experimental IFSs of impurities were acquired by DI-FT-ICR-MS mode. Finally, the elemental composition of all impurities was decisively determined by comparing the experimental and theoretical IFSs. Our results demonstrate that the combined strategy is effective in separating impurities and acquiring accurate mass by HPLC-FT-ICR-MS, obtaining the appropriate samples by fraction collection technology for DI-FT-ICR-MS, and acquiring the IFSs of impurities by DI-FT-ICR-MS. It could be concluded that the strategy is an accurate and standard independent approach to determine the elemental composition of organic impurities in commercial preparations.

A rapid and sensitive UHPLC-FT-ICR MS/MS method for identification of chemical constituents in Rhodiola crenulata extract, rat plasma and rat brain after oral administration.

A rapid and sensitive UHPLC-FT-ICR MS/MS method was developed for the first time to analyze the extract of Rhodiola crenulata and the constituents absorbed into rat blood and brain after oral administration. Under the optimized conditions, a total of 64 chemical constituents were identified or tentatively characterized in vitro in 30min, and also 24 and 9 chemical constituents were detected in rat plasma and brain respectively, by comparing the retention time, accurate mass and/or MS/MS data of blank and dosed sample. The results indicated that the developed UHPLC-FT-ICR MS/MS method was suitable for detection and identifying the chemical constituents in Rhodiola crenulata extract, rat plasma and rat brain, and it could be used as a powerful and reliable analytical strategy for rapid identification of chemical constituents in vitro and in vivo for other traditional Chinese herbal medicines (TCMs). Furthermore, the detected chemical constituents in rat brain could be speculated to be the pharmacodynamic substances of Rhodiola crenulata for Alzheimer's disease (AD) and it could also provide useful chemical information for further mass spectrometry imaging and bioactive substances research on Rhodiola crenulata.