PRDX1 Interfering Peptide Disrupts Amino Acids 70-90 of PRDX1 to Inhibit the TLR4/NF-κB Signaling Pathway and Attenuate Neuroinflammation and Ischemic Brain Injury.

Ischemic stroke ranks among the leading causes of death and disability in humans and is accompanied by motor and cognitive impairment. However, the precise mechanisms underlying injury after stroke and effective treatment strategies require further investigation. Peroxiredoxin-1 (PRDX1) triggers an extensive inflammatory cascade that plays a pivotal role in the pathology of ischemic stroke, resulting in severe brain damage from activated microglia. In the present study, we used molecular dynamics simulation and nuclear magnetic resonance to detect the interaction between PRDX1 and a specific interfering peptide. We used behavioral, morphological, and molecular experimental methods to demonstrate the effect of PRDX1-peptide on cerebral ischemia-reperfusion (I/R) in mice and to investigate the related mechanism. We found that PRDX1-peptide bound specifically to PRDX1 and improved motor and cognitive functions in I/R mice. In addition, pretreatment with PRDX1-peptide reduced the infarct area and decreased the number of apoptotic cells in the penumbra. Furthermore, PRDX1-peptide inhibited microglial activation and downregulated proinflammatory cytokines including IL-1ß, IL-6, and TNF-α through inhibition of the TLR4/NF-κB signaling pathway, thereby attenuating ischemic brain injury. Our findings clarify the precise mechanism underlying PRDX1-induced inflammation after ischemic stroke and suggest that the PRDX1-peptide can significantly alleviate the postischemic inflammatory response by interfering with PRDX1 amino acids 70-90 and thereby inhibiting the TLR4/NF-κB signaling pathway. Our study provides a theoretical basis for a new therapeutic strategy to treat ischemic stroke.

Mobile phone addiction and academic burnout: the mediating role of technology conflict and the protective role of mindfulness.

With the rapid development of Internet technology, more and more college students are facing the threat of mobile phone addiction. However, the relationship and underlying mechanism between mobile phone addiction and academic burnout haven't been explored in depth. This study proves the mediating role of technology conflict and the moderating role of mindfulness in the relation between mobile phone addiction and academic burnout. 752 college students were recruited to complete the questionnaire of mobile phone addiction, technology conflict, mindfulness and academic burnout. Results showed that mobile phone addiction was significantly and positively associated with academic burnout, and this relationship could be mediated by technology conflict. Besides, the direct effect of mobile phone addiction on academic burnout and the indirect effect of technology conflict in this link were moderated by mindfulness. Both these two effects are stronger for college students with lower level of mindfulness. Our findings enrich our understanding of how and when mobile phone addiction was related to academic burnout. Educational professionals and parents should take timely measure to the academic burnout of college students suffering from mobile phone addiction, particularly for those with lower level of mindfulness.

TAT-W61 peptide attenuates neuronal injury through blocking the binding of S100b to the V-domain of Rage during ischemic stroke.

Ischemic stroke is a devastative nervous system disease associated with high mortality and morbidity rates. Unfortunately, no clinically effective neuroprotective drugs are available now. In ischemic stroke, S100 calcium-binding protein b (S100b) binds to receptor for advanced glycation end products (Rage), leading to the neurological injury. Therefore, disruption of the interaction between S100B and Rage can rescue neuronal cells. Here, we designed a peptide, termed TAT-W61, derived from the V domain of Rage which can recognize S100b. Intriguingly, TAT-W61 can reduce the inflammatory caused by ischemic stroke through the direct binding to S100b. The further investigation demonstrated that TAT-W61 can improve pathological infarct volume and reduce the apoptotic rate. Particularly, TAT-W61 significantly improved the learning ability, memory, and motor dysfunction of the mouse in the ischemic stroke model. Our study provides a mechanistic insight into the abnormal expression of S100b and Rage in ischemic stroke and yields an invaluable candidate for the development of drugs in tackling ischemic stroke. KEY MESSAGES: S100b expression is higher in ischemic stroke, in association with a high expression of many genes, especially of Rage. S100b is directly bound to the V-domain of Rage. Blocking the binding of S100b to Rage improves the injury after ischemic stroke.

Gastrodin ameliorates the lipopolysaccharide-induced neuroinflammation in mice by downregulating miR-107-3p.

Background: Neuroinflammation plays a pivotal role in the pathogenesis of Central Nervous System (CNS) diseases. The phenolic glucoside gastrodin (GAS), has been known to treat CNS disorders by exerting anti-inflammatory activities. Our aim was to investigate the potential neuroprotective mechanisms of GAS on lipopolysaccharide (LPS)-induced mice. Methods: Male C57BL/6J mice were treated by LPS, before which GAS was adminisrated. The behavior tests such as forced swim test, tail suspension test, and elevated plus maze were performed to evaluate depressive-anxiety-like behaviors. A high-throughput sequencing (HTS) analysis was performed to screen out distinctive miRNAs which were validated using quantitative real-time PCR. Then, miRNA agomir or NC was injected stereotaxically into hippocampus of mice to explore the role of miRNA on GAS in response to LPS. Furthermore, Immunofluorescence and the hematoxylin and eosin (H&E) staining were employed to observe the cellular morphology. The protein levels of pro-inflammatory factors were evaluated by western blot. Finally, the target mRNA of miRNA was predicted using bioinformatics analysis. GO and KEGG enrichment analyses were conducted to clarify the potential function of target protein, which were visualized by bubble charts. Results: The behavioral data showed that mice in the LPS group had obvious depressive-anxiety-like behaviors, and 100 mg/kg GAS could improve these behavioral changes and alleviate the levels of pro-inflammatory cytokines in the hippocampus when mice were exposed to LPS for 6 h. Meanwhile, LPS-induced microglia and astrocyte activation in the CA1, CA2, CA3, and DG regions of the hippocampus were also reversed by GAS. Furthermore, miR-107-3p were screened out and verified for GAS in response to LPS. Importantly, miR-107-3p overexpression negatively abrogated the neuroprotective effects of GAS. Moreover, KPNA1 might be the target molecular of miR-107-3p. KPNA1 might regulate 12 neuroinflammation-related genes, which were mainly involved in cytokine-mediated signaling pathway. Conclusion: These results suggested that GAS might alleviate the LPS-induced neuroinflammation and depressive-anxiety-like behaviors in mice by downregulating miR-107-3p and upregulating the downstream target KPNA1. The indicates miR-107-3p may provide a new strategy for the treatment of CNS diseases.

The potential role of HO-1 in regulating the MLK3-MKK7-JNK3 module scaffolded by JIP1 during cerebral ischemia/reperfusion in rats.

Heme oxygenase (HO-1), which may be induced by Cobaltic protoporphyrin IX chloride (CoPPIX) or Rosiglitazone (Ros), is a neuroprotective agent that effectively reduces ischemic stroke. Previous studies have shown that the neuroprotective mechanisms of HO-1 are related to JNK signaling. The expression of HO-1 protects cells from death through the JNK signaling pathway. This study aimed to ascertain whether the neuroprotective effect of HO-1 depends on the assembly of the MLK3-MKK7-JNK3 signaling module scaffolded by JIP1 and further influences the JNK signal transmission through HO-1. Prior to the ischemia-reperfusion experiment, CoPPIX was injected through the lateral ventricle for 5 consecutive days or Ros was administered via intraperitoneal administration in the week prior to transient ischemia. Our results demonstrated that HO-1 could inhibit the assembly of the MLK3-MKK7-JNK3 signaling module scaffolded by JIP1 and could ultimately diminish the phosphorylation of JNK3. Furthermore, the inhibition of JNK3 phosphorylation downregulated the level of p-c-Jun and elevated neuronal cell death in the CA1 of the hippocampus. Taken together, these findings suggested that HO-1 could ameliorate brain injury by regulating the MLK3-MKK7-JNK3 signaling module, which was scaffolded by JIP1 and JNK signaling during cerebral ischemia/reperfusion.

Genetic and Antibiotic Resistance Characteristics of Campylobacter jejuni Isolated from Diarrheal Patients, Poultry and Cattle in Shenzhen.

OBJECTIVE: To investigate genetic and antibiotic resistance characteristics of Campylobacter jejuni (C. jejuni) isolated from Shenzhen. METHODS: Multilocs sequence typing and agar dilution methods were used to define the genotype and antibiotic resistance of C. jejuni, respectively. RESULTS: In total, 126 C. jejuni strains were isolated. The prevalence of C. jejuni was 5.3% in diarrheal patients. The prevalence in poultry meat (36.5%) was higher than that in cattle meat (1.1%). However, the prevalence in poultry cloacal swabs (27.0%) was lower than that in cattle stool (57.3%). Sixty-two sequence types were obtained, among which 27 of the STs and 10 alleles were previously unreported. The most frequently observed clonal complexes were ST 21 (11.9%), ST-22 (10.3%), and ST-403 (7.1%). ST-21, ST-45, ST-354, ST-403, and ST-443 complexes overlapped between isolates from patients and cattle, whereas ST-45 and ST-574 complexes overlapped between isolates from patients and poultry. All C. jejuni were resistant to at least one antibiotic. The highest resistance rate was toward ciprofloxacin (89.7%), followed by tetracycline (74.6%), and nalidixic acid (69.0%). CONCLUSION: This is the first report of the genotypes and antibiotic resistance of C. jejuni in Shenzhen. Overlapping clonal complexes were found between isolates from patients and cattle, and between patients and poultry.

Green and facile synthesis of a theranostic nanoprobe with intrinsic biosafety and targeting abilities.

Traditional targeting nanoprobes suffer from the risks of partial loss of targeting activity and nanoparticle aggregation induced by post-synthetic modifications, ambiguous toxicity, tedious synthesis procedures and environmentally hazardous processes. Herein, we report a green and facile strategy to fabricate transferrin-indocyanine green nanoparticles as a smart theranostic agent with intrinsic biosafety and active targeting abilities for near-infrared fluorescent imaging and photothermal therapy of tumors. Simple mixing of transferrin and indocyanine green enables their self-assembly in aqueous solution to form nanoparticles with excellent water solubility, colloidal stability, favorable biocompatibility and impressive active targeting theranostic effects in vitro and in vivo. The transferrin-indocyanine green nanoparticles show great potential in theranostic applications of tumors in clinical therapy.

Biomineralization of Versatile CuS/Gd2 O3 Hybrid Nanoparticles for MR Imaging and Antitumor Photothermal Chemotherapy.

The versatile application of nanoparticles in integrating imaging and therapy has aroused extensive research interest in precision medicine. Of the various nanoparticles that have been studied, CuS has shown great potential in the construction of multifunctional agents, owing to its excellent photothermal heating properties. Herein, we report a facile one-pot biomineralization approach for the preparation of versatile bovine-serum-albumin-conjugated CuS/Gd2 O3 hybrid nanoparticles (BSA-CuS/Gd2 O3 HNPs), which simultaneously possessed strong longitudinal relaxivity, an outstanding photothermal effect, high drug-loading capacity, and pH/temperature-responsive drug release. The versatile nanoparticles were used for magnetic resonance imaging (MRI) and antitumor photothermal chemotherapy, both in vitro and in vivo. In vivo MRI showed that the BSA-CuS/Gd2 O3 HNPs had a long circulation time and effective passive tumor-uptake ability. More importantly, combined in vitro and in vivo therapy demonstrated that drug-loaded BSA-CuS/Gd2 O3 HNPs offered outstanding synergistic therapeutic efficacy for tumor inhibition.

Facile Synthesis of Uniform-Sized Bismuth Nanoparticles for CT Visualization of Gastrointestinal Tract in Vivo.

High-performance and biocompatible contrast agents are the key to accurate diagnosis of various diseases in vivo via CT imaging. Fabrication of pure Bi nanoparticles is the best way to maximize X-ray absorption efficiency due to the ultrahigh X-ray attenuation ability of Bi and 100% content of Bi element. However, high-quality Bi nanoparticles prepared through a facile strategy are still lacking. Herein, we report a simple noninjection method to fabricate uniformly sized pure Bi nanoparticles using only two commercial reagents by simply heating the mixture of raw materials in a short time. The obtained Bi nanoparticles owned highly uniform size, excellent monodispersity, and impressive antioxidant capacity. After being modified with oligosaccharide, the "sweet" Bi nanoprobe with comfortable patient experience and favorable biocompatibility was successfully used in CT visualization of gastrointestinal tract in detail.

The Association Between Metabolic Syndrome and Characteristics of Benign Prostatic Hyperplasia: A Systematic Review and Meta-Analysis.

The purpose of this systematic review was to examine the association of metabolic syndrome (MS) with measures of benign prostatic hyperplasia (BPH) including prostate growth rate, prostate volume, International Prostate Symptom Score (IPSS), prostate-specific antigen (PSA) level, and maximal flow rate.Medline, Cochrane CENTRAL, EMBASE, CBM, and Google Scholar databases were searched until March 23, 2015 using combinations of the keywords benign prostate hyperplasia/BPH, metabolic syndrome, total prostate volume, prostate growth rate, prostate specific antigen, International Prostate Symptom Score/IPSS, maximal flow rate. Cohort or case-control studies of patients with BPH and MS that reported quantitative outcomes were included. The pooled mean differences of the outcome measures were compared between patients with and without MS.A total of 158 potentially relevant studies were identified, and 8 were included in the meta-analysis. The 8 studies included in the meta-analysis contained a total of 3093 BPH patients, wherein 1241 had MS and 1852 did not have MS. BPH patients with MS had a significantly higher prostate growth rate (pooled mean difference = 0.67 mL/y, P < 0.001) and larger prostate volume (pooled mean difference = 6.8 mL, P = 0.010) than the BPH patients without MS. There was no significant difference in IPSS score (pooled mean difference = 1.58, P = 0.202) or maximal flow rate (pooled mean difference = -1.41 mL/s, P = .345) between BPH patients with and without MS. A borderline nonsignificant difference in PSA (pooled mean difference = 0.24 ng/mL, P = 0.056) was noted between BPH patients with and without MS.The results of this meta-analysis are consistent with literature indicating that BPH patients with MS have a higher prostate growth rate and larger prostate volume than those without MS; however, further study is necessary to determine the association of BPH and metabolic disorder elements and the potential risk of disease progression in BPH patients with MS.

Theranostic metal-organic framework core-shell composites for magnetic resonance imaging and drug delivery.

Metal-organic frameworks (MOFs) have shown great potential in designing theranostic probes for cancer diagnosis and therapy due to their unique properties, including versatile structures and composition, tunable particle and pore size, enormous porosity, high surface area, and intrinsic biodegradability. In this study, we demonstrate novel MOF-based theranostic Fe3O4@UiO-66 core-shell composites constructed by in situ growth of a UiO-66 MOF shell on a Fe3O4 core for simultaneous drug delivery and magnetic resonance (MR) imaging. In the composites, the UiO-66 shell is devoted for encapsulating the drug, whereas the Fe3O4 core serves as a MR contrast agent. The Fe3O4@UiO-66 core-shell composites show good biocompatibility, high drug loading capacity, sustained drug release, and outstanding MR imaging capability, as well as effective chemotherapeutic efficacy, demonstrating the feasibility of designing theranostic Fe3O4@UiO-66 core-shell composites for cancer diagnosis and therapy.

Neuroprotection of Sevoflurane Against Ischemia/Reperfusion-Induced Brain Injury Through Inhibiting JNK3/Caspase-3 by Enhancing Akt Signaling Pathway.

In this study, we investigated the neuroprotective effect of sevoflurane against ischemic brain injury and its underlying molecular mechanisms. Transient global brain ischemia was induced by 4-vessel occlusion in adult male Sprague-Dawley rats. The rats were pretreated with sevoflurane alone or sevoflurane combined with LY294002/wortmannin (selective inhibitor of PI3K) before ischemia. Cresyl violet staining was used to examine the survival of hippocampal CA1 pyramidal neurons. Immunoblotting and immunoprecipitation were performed to measure the phosphorylation of Akt1, PRAS40, ASK1, and JNK3 and the expression of cleaved-caspase-3. The results demonstrated that a moderate dose of sevoflurane inhalation of 2% for 2 h had significant neuroprotective effects against ischemia/reperfusion induced hippocampal neuron death. Sevoflurane significantly increased Akt and PRAS40 phosphorylation and decreased the phosphorylation of ASK1 at 6 h after reperfusion and the phosphorylation of JNK3 at 3 days after reperfusion following 15 min of transient global brain ischemia. Conversely, LY294002 and wortmannin significantly inhibited the effects of sevoflurane. Taken together, the results suggest that sevoflurane could suppress ischemic brain injury by downregulating the activation of the ASK1/JNK3 cascade via increasing the phosphorylation of Akt1 during ischemia/reperfusion.

The complete mitochondrial genome of the Fossorochromis rostratus.

The Fossorochromis rostratus is a species of cichlid endemic to Lake Malawi in East Africa. In this study, we first reported the complete mitochondrial genome of F. rostratus. The whole mitochondrial genome is 16 581 bp in length, which contains 13 protein-coding genes, 22 transfer RNA genes, and two ribosomal RNA genes. The GC content of this mitochondrial genome is 45.96% (27.47% A, 26.57%T, 30.12% C, and 15.84% G), similar to Astatotilapia calliptera (the GC content of 45.90%). We constructed a phylogenetic tree on the complete mitochondrial genomes of these two species and other 10 closely related species to show their phylogenic relationship. The complete mitochondrial genome of F. rostratus and its phylogenic relationship with other related species would facilitate our understanding of the evolution of Cichlidae mitochondrial genome.

Facile preparation of hyaluronic acid and transferrin co-modified Fe3O4 nanoparticles with inherent biocompatibility for dual-targeting magnetic resonance imaging of tumors in vivo.

Clinical diagnosis of malignant tumors using nanoprobes needs severe improvements in the aspects of sensitivity and biocompatibility. Integrating a dual-targeting strategy with the selection of human-inherent elements and molecules as raw materials shows great potential in the development of a biosafe and sensitive nanoplatform. To carry out the proposed design, we constructed a biocompatible, dual-targeting MR imaging nanoprobe, based on Fe3O4 nanoparticles (NPs) co-modified with inherently innoxious hyaluronic acid (HA) and transferrin (Tf). HA was used as both a template and a targeting molecule to form Fe3O4@HA NPs through a one-step co-precipitation method, which were then further modified with Tf to obtain the dual-targeting Fe3O4@HA@Tf NPs at room temperature. The excellent biocompatibility of the nanoprobe was demonstrated via toxicity assays in vitro and in vivo. The desirable dual-targeting ability towards tumor cells was confirmed by a cellular uptake test (Hela cells, overexpressing both CD44 and transferrin receptors), and the developed nanoprobe was successfully applied in tumor-targeted MR imaging in vivo. In summation, we developed a dual-targeting Fe3O4 nanoprobe, following a facile procedure at room temperature. The nanoprobe showed a high targeting ability towards tumor cells and excellent biocompatibility, which showed its great potential to be applied in the clinical diagnosis of tumors.

BSA-directed synthesis of CuS nanoparticles as a biocompatible photothermal agent for tumor ablation in vivo.

Photothermal therapy as a physical therapeutic approach has greatly attracted research interest due to its negligible systemic effects. Among the various photothermal agents, CuS nanoparticles have been widely used due to their easy preparation, low cost, high stability and strong absorption in the NIR region. However, the ambiguous biotoxicity of CuS nanoparticles limited their bio-application. So it is highly desirable to develop biocompatible CuS photothermal agents with the potential of clinical translation. Herein, we report a novel method to synthesize biocompatible CuS nanoparticles for photothermal therapy using bovine serum albumin (BSA) as a template via mimicking biomaterialization processes. Owing to the inherent biocompatibility of BSA, the toxicity assays in vitro and in vivo showed that BSA-CuS nanoparticles possessed good biocompatibility. In vitro and in vivo photothermal therapies were performed and good results were obtained. The bulk of the HeLa cells treated with BSA-CuS nanoparticles under laser irradiation (808 nm) were killed, and the tumor tissues of mice were also successfully eliminated without causing any obvious systemic damage. In summary, a novel strategy for the synthesis of CuS nanoparticles was developed using BSA as the template, and the excellent biocompatibility and efficient photothermal therapy effects of BSA-CuS nanoparticles show great potential as an ideal photothermal agent for cancer treatment.

[Characteristics of ammonium N and nitrate N accumulation in dryland soil in relation with wheat yield].

A total of eleven field trials in Yongshou, Shaanxi Province and seven in Luoyang, Henan Province were conducted with two treatments (without N as control and with 150 kg N x hm(-2) addition). The wheat biomass and seed yield were determined, and so were the nitrate and ammonium N concentrations in five layers (0-20, 20-40, 40-60, 60-80, 80-100 cm) at each trial site. Results showed that soil ammonium concentrations in the two provinces were very low while nitrate N concentrations were relatively high. Soil nitrate N occupied 91% of the total mineral N, and exhibited the same trend as the total mineral N in reflecting soil N supplying capacity. Without N application, the cumulative nitrate N amounts in the 0-40, 0-60, 0-80 and 0-100 cm layers in Yongshou were significantly correlated with wheat biomass and seed yield while no such correlation existed in Luoyang. With N addition, the relations of cumulative nitrate N of the different layers to wheat biomass and yield were greatly declined in Yongshou whereas those of Luoyang were changed to be negative. The yield increases were significantly correlated with the amount of nitrate N accumulated in the 0-80 and 0-100 cm layers of the two sites under N addition. Wheat mainly depended on nitrate N from the 0-20 cm layer at seedling stage, 0-40 cm at reviving, and 0-60 cm at elongation stages, and could utilize 0-100 cm nitrate N at maturity. After wheat harvest, the concentration of ammonium N was not significantly different from the initial value while that of nitrate N greatly decreased.

Mangiferin regulates interleukin-6 and cystathionine-b-synthase in lipopolysaccharide-induced brain injury.

Mangiferin has been extensively applied in different fields due to its anti-inflammatory properties. However, the precise mechanism used by mangiferin on lipopolysaccharide (LPS)-induced inflammation has not been elucidated. Here, we discuss the potential mechanism of mangiferin during a LPS-induced brain injury. Brain injury was induced in ICR mice via intraperitoneal LPS injection (5 mg/kg). Open- and closed-field tests were used to detect the behaviors of mice, while immunoblotting was performed to measure the expression of interleukin-6 (IL-6) and cystathionine-b-synthase (CBS) in the hippocampus after mangiferin was orally administered (p.o.). Mangiferin relieved LPS-induced sickness 6 and 24 h after LPS injection; in addition, this compound suppressed LPS-induced IL-6 production after 24 h of LPS induction as well as the downregulation of LPS-induced CBS expression after 6 and 24 h of LPS treatment in the hippocampus. Therefore, mangiferin attenuated sickness behavior by regulating the expression of IL-6 and CBS.

Fabrication of ZIF-8@SiO2 core-shell microspheres as the stationary phase for high-performance liquid chromatography.

The unique features of high porosity, shape selectivity, and multiple active sites make metal-organic frameworks (MOFs) promising as novel stationary phases for high-performance liquid chromatography (HPLC). However, the wide particle size distribution and irregular shape of conventional MOFs lead to lower column efficiency of such MOF-packed columns. Herein, the fabrication of monodisperse MOF@SiO2 core-shell microspheres as the stationary phase for HPLC to overcome the above-mentioned problems is reported. Zeolitic imidazolate framework 8 (ZIF-8) was used as an example of MOFs due to its permanent porosity, uniform pore size, and exceptional chemical stability. Unique carboxyl-modified silica spheres were used as the support to grow the ZIF-8 shell. The fabricated monodisperse ZIF-8@SiO2 packed columns (5 cm long × 4.6 mm i.d.) show high column efficiency (23,000 plates m(-1) for bisphenol A) for the HPLC separation of endocrine-disrupting chemicals (bisphenol A, ß-estradiol, and p-(tert-octyl)phenol) and pesticides (thiamethoxam, hexaflumuron, chlorantraniliprole, and pymetrozine) within 7 min with good relative standard deviations for 11 replicate separations of the analytes (0.01-0.39, 0.65-1.7, 0.70-1.3, and 0.17-0.91% for retention time, peak area, peak height, and half peak width, respectively). The ZIF-8@SiO2 microspheres combine the advantages of the good column packing properties of the uniform monodisperse silica microspheres and the separation ability of the ZIF-8 crystals.

Incorporation of metal-organic framework UiO-66 into porous polymer monoliths to enhance the liquid chromatographic separation of small molecules.

UiO-66 incorporated monoliths were fabricated to enhance the liquid chromatographic separation of small molecules with high column efficiency and good reproducibility.

Reversal effect of rosmarinic acid on multidrug resistance in SGC7901/Adr cell.

Multidrug resistance (MDR) has been a major problem in cancer chemotherapy. In this study, the aim was to explore the reversal effect and its potential mechanism of rosmarinic acid (RA) on SGC7901/Adr cells. 3-(4,5-Dimethylthiazol)-2,5-diphenyl tetrazolium bromide (MTT) assay was used to investigate the reversal index of RA in SGC7901/Adr cell line. The intracellular accumulation of adriamycin, rhodamine123 (Rh123), and the expression of P-glycoprotein (P-gp) were assayed by flow cytometry. The influence of RA on the transcription of MDR1 gene was determined by reverse transcription-polymerase chain reaction. The results showed that RA could reverse the MDR of SGC7901/Adr cells, increase the intracellular accumulation of Adr and Rh123, and decrease the transcription of MDR1 gene and the expression of P-gp in SGC7901/Adr cells. These results indicated that RA was a potential multidrug resistance-reversing agent and warranted further investigations.