CD97 inhibits osteoclast differentiation via Rap1a/ERK pathway under compression

Acceleration of tooth movement during orthodontic treatment is challenging, with osteoclast-mediated bone resorption on the compressive side being the rate-limiting step. Recent studies have demonstrated that mechanoreceptors on the surface of monocytes/macrophages, especially adhesion G protein-coupled receptors (aGPCRs), play important roles in force sensing.However, its role in the regulation of osteoclast differentiation remains unclear. Herein, through single-cell analysis, we revealed that CD97, a novel mechanosensitive aGPCR, was expressed in macrophages. Compression upregulated CD97 expression and inhibited osteoclast differentiation;while knockdown of CD97 partially rescued osteoclast differentiation. It suggests that CD97 may be an important mechanosensitive receptor during osteoclast differentiation. RNA sequencing analysis showed that the Rap1a/ERK signalling pathway mediates the effects of CD97 on osteoclast differentiation under compression. Consistently, we clarified that administration of the Rap1a inhibitor GGTI298 increased osteoclast activity, thereby accelerating tooth movement. In conclusion,our results indicate that CD97 suppresses osteoclast differentiation through the Rap1a/ERK signalling pathway under orthodontic compressive force.

Edaravone-loaded poly(amino acid) nanogel inhibits ferroptosis for neuroprotection in cerebral ischemia injury

Neurological injury caused by ischemic stroke is a major cause of permanent disability and death. The currently available neuroprotective drugs fail to achieve desired therapeutic efficacy mainly due to short circulation half-life and poor blood−brain barrier (BBB) permeability. For that, an edaravone-loaded pH/glutathione (pH/GSH) dual-responsive poly(amino acid) nanogel (NG/EDA) was developed to improve the neuroprotection of EDA. The nanogel was triggered by acidic and EDA-induced high-level GSH microenvironments, which enabled the selective and sustained release of EDA at the site of ischemic injury. NG/EDA exhibited a uniform sub-spherical morphology with a mean hydrodynamic diameter of 112.3 ± 8.2 nm. NG/EDA efficiently accumulated at the cerebral ischemic injury site of permanent middle cerebral artery occlusion (pMCAO) mice, showing an efficient BBB crossing feature. Notably, NG/EDA with 50 µM EDA significantly increased neuron survival (29.3%) following oxygen and glucose deprivation by inhibiting ferroptosis. In addition, administering NG/EDA for 7 d significantly reduced infarct volume to 22.2% ± 7.2% and decreased neurobehavioral scores from 9.0 ± 0.6 to 2.0 ± 0.8. Such a pH/GSH dual-responsive nanoplatform might provide a unique and promising modality for neuroprotection in ischemic stroke and other central nervous system diseases.

Netrin-1 blockade inhibits tumour growth and EMT features in endometrial cancer

Netrin-1 is upregulated in cancers as a protumoural mechanism1.Here we describe netrin-1 upregulation in a majority of human endometrial carcinomas(ECs)and demonstrate that netrin-1 blockade,using an anti-netrin-1 antibody(NP137),is effective in reduction of tumour progression in an EC mouse model.We next examined the efficacy of NP137,as a first-in-class single agent,in a Phase I trial comprising 14 patients with advanced EC.As best response we observed 8 stable disease(8 out of 14,57.1%)and 1 objective response as RECIST v.1.1(partial response,1 out of 14(7.1%),51.16%reduction in target lesions at 6 weeks and up to 54.65%reduction during the following 6 months).To evaluate the NP137 mechanism of action,mouse tumour gene profiling was performed,and we observed,in addition to cell death induction,that NP137 inhibited epithelial-to mesenchymal transition(EMT).By performing bulk RNA sequencing(RNA-seq),spatial transcriptomics and single-cell RNA seq on paired pre-and on-treatment biopsies from patients with EC from the NP137 trial,we noted a net reduction in tumour EMT.This was associated with changes in immune infiltrate and increased interactions between cancer cells and the tumour microenvironment.Given the importance of EMT in resistance to current standards of care2,we show in the EC mouse model that a combination of NP137 with carboplatin-paclitaxel outperformed carboplatin-paclitaxel alone.Our results identify netrin-1 blockade as a clinical strategy triggering both tumour debulking and EMT inhibition,thus potentially alleviating resistance to standard treatments.

Panax notogiseng saponin inhibits ischemia-induced apoptosis by activating PI3K/Akt signal pathway in cardiomyocytes

The panax notoginseng saponin(PNS) had been clinically used for the treatment of cardiovascular diseases and stroke in China.It had been demonstrated that PNS could protect cardiomyocytes from injury induced by ischemi- a,but the underlying molecular mechanisms of this protective effect were still unclear.This study was aimed to investigate the protective effect and molecular mechanisms of PNS on apoptosis in H9c2 cells in vitro and rat myocardial ischemia injury model in vivo.Annexin-V/PI assay shew that PNS could protect H9c2 cells from apoptosis induced by serum, glucose and oxygen deprivation(SGOD) in a dose-dependent manner.However,the anti-apoptotic effect of PNS was reversed by LY294002,a specific PI3K inhibitor.This antiapoptotic effect of PNS was confirmed by JC-1,a specific probe of mitochondrial membrane potential staining.PNS could significantly increase phos-Akt in H9c2 cells by Western blot assays and its effect could be inhibited by LY294002.Furthermore,PNS could improve ischemic-induced left ventricular function as reflected by EF,LVDd and LVDs.PNS could also inhibited cellular apoptosis in myocardial tissues in ischemic rats by TUNEL assay.PNS administration also increased the expression of phos-Akt in rat ischemic myocardial tissues.These results suggested that PNS could protect myocardial cells from apoptosis induced by ischemia in vitro model and in vivo model through activating-PI3K/Akt signal pathway which may be meaningful for further understanding the molecular mechanisms of cardiac protection of PNS.And the results might be useful in treatment of myocardial ischemia in future.

Selective serotonin re-uptake inhibitor sertraline inhibits bone healing in a calvarial defect model

Bone wound healing is a highly dynamic and precisely controlled process through which damaged bone undergoes repair and complete regeneration. External factors can alter this process, leading to delayed or failed bone wound healing. The findings of recent studies suggest that the use of selective serotonin reuptake inhibitors(SSRIs) can reduce bone mass, precipitate osteoporotic fractures and increase the rate of dental implant failure. With 10% of Americans prescribed antidepressants, the potential of SSRIs to impair bone healing may adversely affect millions of patients’ ability to heal after sustaining trauma. Here, we investigate the effect of the SSRI sertraline on bone healing through pre-treatment with(10 mg·kg-1sertraline in drinking water, n = 26) or without(control, n = 30) SSRI followed by the creation of a 5-mm calvarial defect. Animals were randomized into three surgical groups:(a) empty/sham,(b) implanted with a DermaMatrix scaffold soak-loaded with sterile PBS or(c) DermaMatrix soak-loaded with542.5 ng BMP2. SSRI exposure continued until sacrifice in the exposed groups at 4 weeks after surgery. Sertraline exposure resulted in decreased bone healing with significant decreases in trabecular thickness, trabecular number and osteoclast dysfunction while significantly increasing mature collagen fiber formation. These findings indicate that sertraline exposure can impair bone wound healing through disruption of bone repair and regeneration while promoting or defaulting to scar formation within the defect site.

sDR5-Fc inhibits macrophage M1 polarization by blocking the glycolysis

BACKGROUND M1 polarization of macrophages is an important pathological process in myocardial ischemia reperfusion injury, which is the major obstacle for the treatment of acute myocardial infarction. Currently, the strategies and mechanisms of inhibiting M1 polarization are poorly explored. This study aims to investigate the role of soluble death receptor 5-Fc(s DR5-Fc) in regulating M1 polarization of macrophages under extreme conditions and explore the mechanisms from the aspect of glycolysis.METHODS Extreme conditions were induced in RAW264.7 cells. Real-time quantitative polymerase chain reaction and western blot were used to detect the expression of m RNA and proteins, respectively. Cell counting kit-8 was used to investigate the proliferation activity of cells. Expression levels of inflammatory cytokines were determined by enzyme-linked immunosorbent assay.RESULTS We found that s DR5-Fc rescues the proliferation of macrophages under extreme conditions, including nutrition deficiency, excessive peroxide, and ultraviolet irradiation. In addition, administration of s DR5-Fc inhibits the M1 polarization of macrophages induced by lipopolysaccharide(LPS) and interferon-gamma(IFN-γ), as the expression of M1 polarization markers CD86, CXC motif chemokine ligand 10, matrix metalloproteinase 9, and tumor necrosis factor-α, as well as the secretion of inflammatory factors interleukin(IL)-1β and IL-6, were significantly decreased. By further investigation of the mechanisms, the results showed that s DR5-Fc can recover the LPS and IFN-γ induced p H reduction, lactic acid elevation, and increased expression of hexokinase 2 and glucose transporter 1, which were markers of glycolysis in macrophages.CONCLUSIONS s DR5-Fc inhibits the M1 polarization of macrophages by blocking the glycolysis, which provides a new direction for the development of strategies in the treatment of myocardial ischemia reperfusion injury.

Inosine inhibits apoptosis and cytochrome C mRNA expression in rat neurons after cerebral ischemia/reperfusion

BACKGROUND: It has been demonstrated that adenosine can induce glial cell to release cytochrome C, enhance expression of apoptotic gene bax, inhibit anti-apoptotic gene bcl-2, and activate caspase-3 to apoptosis; Whereas inosine can inhibit neuronal apoptosis which is similar to bcl-2. OBJECTIVE: To observe the effects of inosine on neuronal apoptosis and expression of cytochrome C mRNA in rats after focal cerebral ischemia/reperfusion, and analyze the pathway of its neuroprotective effect. DESIGN: A randomised controlled animal trial. SETTINGS: Department of Neurology, Rongcheng Second People's Hospital; Department of Neurology, Affiliated Union Hospital, Tongji Medical College, Huazhong University of Science and Technology. MATERIALS: Sixty-eight rats, weighing 230-280 g and clean grade, were used. TdT-mediated dUTP-biotin nick end labeling (TUNEL) and cytochrome C mRNA in situ hybridization kits and DAB staining kit were purchased from Wuhan Boster Biological Co., Ltd.; Inosine injection [200 mg (2 mL) each] from Qingdao First Pharmaceutical Factory. METHODS: The experiment was accomplished in the animal experimental center in Tongji Medical College of Huazhong University of Science and Technology from December 2003 to June 2005. ① Sixty-four rats were made into focal ischemia by middle cerebral artery occlusion (MCAO) with a nylon monofilament suture. The successfully induced rats were assigned to inosine group (n =32) and model group (n =32) at random. Rats in the inosine group were intraperitoneally administrated with inosine in dose of 100 mg/kg preoperatively, twice a day, 7 days in all. The rats in the control group were injected with the same dose of saline solution by the similar way preoperatively. Each group was randomized into ischemia /reperfusion 2, 6, 12, 24 hours, 2, 3, 7 and 14 days subgroups consisted of 4 rats. The other 4 rats were taken as the sham-operated group, the rats were given the same treatment except for not introduced the filament into the external carotid artery stump, and brain tissue was removed at 2 hours of reperfusion. ② In situ hybridization was performed to examine the expression of cytochrome C mRNA while TUNEL staining was made to characterize apoptosis. ③ The t test was used to compare the difference of measurement data. MAIN OUTCOME MEASURES: ① Neuronal apoptosis in the different regions of the ischemic brain tissue; ② Expression of cytochrome C mRNA in the different regions at different time points after MCAO. RESULTS: All the 68 rats were involved in the analysis of results. ① Neuronal apoptosis: A small number of TUNEL-positive cells were detected in the sham-operated brain and non-ischemic brain. The number of apoptotic cells in the ischemic cortex peaked at 24 hours of reperfusion [(72.00±1.98) cells] and that in the striatum peaked at 2 days [(94.75±3.57) cells], then decreased to the level of sham-operated group at 14 days. Inosine could reduce apoptotic cells from 12 hours to 7 days of reperfusion as compared with the model group (t =6.19-26.67, P < 0.01). ② Cytochrome C mRNA expression: There was weak expression of cytochrome C mRNA in both sham-operated brain and contralateral brain. Cytochrome C was detected at 2 hours of reperfusion in ischemic brain [(25.75±3.50), (39.75±2.49) cells], and strongly increased to a peak at 12 hours and 24 hours of reperfusion in cortex and striatum [(122.50±6.69), (119.25±5.12) cells], respectively. Furthermore, inosine could significantly decrease cytochrome C expression in cortex at 12 hours to 14 days of reperfusion after ischemic reperfusion and that in striatum at 12 hours to 3 days (t =8.67-43.26, P < 0.01). CONCLUSION: Inosine can exert a neuroprotective effect by inhibiting apoptosis and cytochrome C mRNA expression.

3-54 DNA-PKcs Deficiency Inhibits Glioblastoma Cell-Derived Angiogenesis after Ionizing Radiation

DNA-dependent protein kinase catalytic subunit (DNA-PKcs) plays a critical role in non-homologous end-joiningrepair of DNA double strand breaks (DSB) induced by ionizing radiation (IR) [1]. Little is known, however, regardingthe relationship between DNA-PKcs and IR induced angiogenesis; thus, in this study we aimed to further elucidatethis relationship. Our findings revealed that lack of DNA-PKcs expression or activity sensitized glioma cells toradiation due to the defective DNA DSB repairs and inhibition of phosphorylated Akt Ser473. Moreover, DNAPKcsdeficiency apparently mitigated IR-induced migration, invasion and tube formation of human microvascularendothelial cell (HMEC-1) in conditioned media derived from irradiated DNA-PKcs mutant M059J glioma cells orM059K glioma cells that have inhibited DNA-PKcs kinase activity due to the specific inhibitor NU7026 or siRNAknockdown(Fig. 1).

CREG inhibits VSMCs proliferation by modulating the internalization of IGFII

Background To study the molecular mechanisms of CREG(the cellular repressor of E1A-stimulated gene) on proliferation of VSMCs in vitro.Methods The pRc/CMV-CREG plasmid or the pSM2-siCREG plasmid was transferred into human vascular smooth muscle cells(hVSMCs) to produce the cell clone that over-expression or down-expression of CREG respectively.BrdU assay and FACS cell cycle analysis were used to detect the proliferation of cells.Western blotting and immunocytochemistry show the expression and localization of IGF2R in hVSMCs.RT-PCR and ELISA assay determined the expression and secretion of IGFII factor. Alex488-labeled rhIGFII was used to investigate the endocysis of cells.And the blockade of IGFII internalization by treatment both the neutralized antibody of anti-IGF2R and rsIGF2R detected the effect of IGFII on VSMCs growth. Furthermore,Western blotting and signal pathway inhibitor were used to analysis the activation of PI3K/AKT and ERK on VSMCs proliferation.Results Western blotting identified that the expression of CREG in hVSMCs-CREG cells increased compared to control cell,and the decreased obviously in hVSMCs-siCREG cells.Meanwhile,the overexpression of CREG in cells was detected to inhibit the proliferation of VSMCs and to enhance the distribution of IGF2R in cellular membrane.Furthermore,overexpression of CREG also accelerated the endocysis of IGFII in hVSMCs-CREG,and attenuate the secretion of IGFII into cell medium by ELISA analysis and Alex488 labeled IGFII analysis.Blockade experiments both neutralized antibody of IGF2R and rhIGF2R fragment determined that enhancement of IGFII secretion promoted the VSMCs proliferation,and PI3K/AKT and ERK signal pathway mediated the effect of IGFII on VSMCs.Conclusions Altogether, these data indicate that CREG inhibits the proliferation of hVSMCs through interfering into the internalization pathway of IGF2R-IGFII.

Down-regulation of Notch-1 gene expression inhibits growth of TJ-905 glioblastoma

Objective To study the inhibitory effect of siRNA on glioblastoma (GBM) Notch-1 gene expression in addition to the growth of TJ-905 glioblastoma. Methods Three small interference RNAs (siRNAs) targeting Notch1 gene,named siRNA1,siRNA2,siRNA3,synthesized chemically in vitro with gene bank BLAST. TJ-905 cells were transfected twice with the siRNA by using Oligofectamine

Vibramycin inhibits the expression of MMP-2 and the invasiveness of PC-3 cells in vitro

Objective To study the inhibition of vibramycin on the expression of matrix metalloproteinase-2 (MMP-2) and the invasiveness of androgen-independent prostatic carcinoma cell line PC - 3 in vitro. Methods Immunohistochemistry stain and transwell chamber were used to investigate the expression of MMP-2 in different concentration of vibramycin treated PC-3 cells and the invasive ability of different concentration of vibramycin treated PC-3 cell. Results The positive rate of MMP-2 inJune 2003 Vol12 No2 PC-3 cells was decreased at a concentration of 5 mg/L of vibramycin and decreased dramatically at the concentration of 10 mg/L. The cells moved throuth the membrane was(82. 0 ± 4.6)/field in the control group, while decreased to(26.1 ±3.6),(7.2 ±2.2) and(3.3± 0.7)/field in 5,10 and 20 mg/L vibramycin treated PC-3 cell respectively. Conclusion Vibramycin can inhibit the invasiveness and metastatasis of PC-3 cells, the mechanism of which is related to the inhibition of MMP-2 in PC-3 cell.10refs.

Sirolimus inhibits growth of human hepatoma cells alone or combined with tacrolimus, while tacrolimus promotes cell growth

AIM: Standard immunosuppression after organ transplantation stimulates tumor growth. Sirolimus has a strong antiproliferative and a tumor inhibiting effect. The purpose is to assess the effect on tumor growth of the immunosuppressive compounds sirolimus and tacrolimus alone and in combination on cells of human hepatocellular carcinoma.METHODS: We used the human cell lines SK-Hep 1 and Hep 3B derived from hepatocellular carcinoma. Proliferation analyses after treatment with sirolimus, tacrolimus, or the combination of both were performed. FACS analyses were done to reveal cell cycle changes and apoptotic cell death. The expression of apoptosis-related proteins was estimated by Western blots.RESULTS: Sirolimus alone or combined with tacrolimus inhibited the growth of both cell lines after 5 d by up to 35% in SK-Hep 1 cells, and by up to 68% in Hep 3B cells at 25 ng/mL. Tacrolimus alone stimulated the growth by 12% after 5 ng/mL and by 25% after 25 ng/mL in Hep 3B cells. We found an increase of apoptotic Hep 3B cells from 6 to 16%, and a G1-arrest in SK-Hep 1 cells with an increase of cells from 61 to 82%, when sirolimus and tacrolimus were combined. Bcl-2 was down-regulated in Hep 3B, but not in SK-Hep 1 cells after combined treatment.CONCLUSION: Sirolimus appears to inhibit the growth of hepatocellular carcinoma cells alone and in combination with tacrolimus. Sirolimus seems to inhibit the growth stimulation of tacrolimus.

TAZ inhibits osteoclastogenesis by attenuating TAK1/NF-κB signaling

Osteoporosis is an osteolytic disorder commonly associated with excessive osteoclast formation.Transcriptional coactivator with PDZ-binding motif(TAZ)is a key downstream effector of the Hippo signaling pathway;it was suggested to be involved in the regulation of bone homeostasis.However,the exact role of TAZ in osteoclasts has not yet been established.In this study,we demonstrated that global knockout and osteoclast-specific knockout of TAZ led to a low-bone mass phenotype due to elevated osteoclast formation,which was further evidenced by in vitro osteoclast formation assays.Moreover,the overexpression of TAZ inhibited RANKL-induced osteoclast formation,whereas silencing of TAZ reduced it.Mechanistically,TAZ bound to TGF-activated kinase 1(TAK1)and reciprocally inhibited NF-κB signaling,suppressing osteoclast differentiation.Collectively,our findings highlight an essential role of TAZ in the regulation of osteoclastogenesis in osteoporosis and its underlying mechanism.

Fentanyl inhibits glucose-stimulated insulin release from β-cells in rat pancreatic islets

AIM： TO explore the effects of fentanyl on insulin release from freshly isolated rat pancreatic islets in static culture. METHODS： Islets were isolated from the pancreas of mature Sprague Dawley rats by common bile duct intraductal collagenase V digestion and were purified by discontinuous Ficoll density gradient centrifugation. The islets were divided into four groups according to the fentanyl concentration： control group （0 ng/mL）, group I （0.3 ng/mL）, group I （3.0 ng/mL）, and group III （30 ng/mL）. In each group, the islets were co-cultured for 48 h with drugs under static conditions with fentanyl alone, fentanyl ＋ 0.1 μg/mL naloxone or fentanyl ＋ 1.0 μg/mL naloxone. Cell viability was assessed by the MTT assay. Insulin release in response to low and high concentrations （2.8 mmol/L and 16.7 mmol/L, respectively） of glucose was investigated and electron microscopy morphological assessment was performed. RESULTS： Low- and high-glucose-stimulated insulin release in the control group was significantly higher than in groups I and II （62.33 ± 9.67 μIU vs 47.75 ± 8.47 μIU, 39.67 ± 6.18 μIU and 125.5 ± 22.04 μIU vs 96.17 ± 14.17 μIU, 75.17 ± 13.57 μIU, respectively, P 〈 0.01） and was lowest in group III （P 〈 0.01）. After adding 1 μg/mL naloxone, insulin release in groups II and II was not different from the control group. Electron microscopy studies showed that the islets were damaged by 30 ng/ml fentanyl. CONCLUSION： Fentanyl inhibited glucose-stimulated insulin release from rat islets, which could be prevented by naloxone. Higher concentrations of fentanyl significantly damaged β-cells of rat islets.

Hydrogen sulfide inhibits ethylene-induced petiole abscission in tomato(Solanum lycopersicum L.)

Abscission is a dynamic physiological process that is ubiquitous in plants and can also be an essential agronomic trait in crops,thus attracting attention from plant growers and breeders.In general,the process of plant organ abscission can be divided into four steps,among which the step to obtain the competence to respond to abscission signals(step 2)is the most complex;however,the molecular mechanism underlying this process remains unclear.In this study,we found that hydrogen sulfide(H_(2)S)inhibited the abscission of the tomato petiole in a dose-dependent manner,and the abscission of the petiole was accelerated when an H_(2)S scavenger was applied.Further enzymatic activity and gene expression analyses showed that H_(2)S suppressed the activity of enzymes capable of modifying the cell wall by inhibiting the usual upregulation of the transcription of the corresponding genes during the abscission process but not by affecting the activities of these enzymes by direct posttranslational modification.H_(2)S treatment upregulated the expression levels of SlIAA3 and SlIAA4 but downregulated the transcription of ILR-L3 and ILR-L4 in the earlier stages of the abscission process,indicating that H_(2)S probably functioned in the second step of the abscission process by preventing the abscission zone cells from obtaining the competence to respond to abscission signals by modulating the content of the bioactive-free auxin in these cells.Moreover,similar H_(2)S inhibitory effects were also demonstrated in the process of floral organ abscission and anther dehiscence in other plant species,suggesting a ubiquitous role for H_(2)S in cell separation processes.

A soluble FcγR homolog inhibits Ig M antibody production in ayu spleen cells

Classical Fc receptors (FcRs) mediate the binding to and recognition of the Fc portion of antibodies and play an important role during immune responses in mammals. Although proteins similar to soluble FcRs have been identified in fish, little is known about the role of such proteins in fish immunity. Here, we cloned a cDNA sequence encoding a soluble Fc receptor for an immunoglobulin G (FcγR) homolog from ayu (Plecoglossus altivelis)(PaFcγRl). The predicted protein was composed of two immunoglobulin C2-like domains but lacked a transmembrane segment and a cytoplasmic tail. The PaFcγRl transcripts were distributed at low levels in all tested tissues, but significantly increased after Vibrio anguillarum infection. The PaFcγRl protein was expressed in the head kidney, trunk kidney, and neutrophils. Recombinant PaFcγRl (rPaFcγRl) was secreted when transfected into mammalian cells and the native protein was also detected in serum upon infection. rPaFcγRl was also demonstrated to bind to ayu IgM, as assessed by cell transfection. Suppressive activity of the recombinant mature protein of PaFcγRl (rPaFcγRlm) on in vitro anti-sheep red blood cell (SRBC) responses was detected by a modified hemolytic plaque forming cell assay. In conclusion, our study revealed that PaFcγRl is closely involved in the negative regulation of IgM production in the ayu spleen.

miR-4651 inhibits cell proliferation of gingival mesenchymal stem cells by inhibiting HMGA2 under nifedipine treatment

Drug-induced gingival overgrowth(DIGO) is recognized as a side effect of nifedipine(NIF);however, the underlying molecular mechanisms remain unknown. In this study, we found that overexpressed mi R-4651 inhibits cell proliferation and induces G0/G1-phase arrest in gingival mesenchymal stem cells(GMSCs) with or without NIF treatment. Furthermore, sequential window acquisition of all theoretical mass spectra(SWATH-MS) analysis, bioinformatics analysis, and dual-luciferase report assay results confirmed that high-mobility group AT-hook 2(HMGA2) is the downstream target gene of mi R-4651. Overexpression of HMGA2 enhanced GMSC proliferation and accelerated the cell cycle with or without NIF treatment. The present study demonstrates that mi R-4651 inhibits the proliferation of GMSCs and arrests the cell cycle at the G0/G1 phase by upregulating cyclin D and CDK2 while downregulating cyclin E through inhibition of HMGA2 under NIF stimulation. These findings reveal a novel mechanism regulating DIGO progression and suggest the potential of mi R-4651 and HMGA2 as therapeutic targets.

Mistletoe alkali inhibits peroxidation in rat liver and kidney

AIM： To explore the antioxidant and free radica scavenger properties of mistletoe alkali （MA）. METHODS： The antioxidant effect of mistletoe alkali on the oxidative stress induced by carbon tetrachloride （CCh） in rats was investigated. The rats were divided into four groups （n = 8）： CCh-treated group （1 mL/kg body weight）, MA -treated group （90 mg/kg）, CCh＋MA-treated group and normal control group. After 4 wk of treatment, the level of malondialdehyde （MDA）, a lipid peroxidation product （LPO） was measured in serum and homogenates of liver and kidney. Also, the level of glutathione （GSH）, and activities of glutathione reductase （GR）, glutathione peroxidase （GSPx）, superoxide dismutase （SOD）, and glutathione-S-transferase （GST） in liver and kidney were determined. Scavenging effects on hydroxyl free radicals produced in vitro by Fenton reaction were studied by ESR methods using 5,5-dimethyl-1-pyrroline-N-oxide （DMPO） as a spin trap reagent and H2O2/UV as the OH· source. Urinary 8-hydroxydeoxyguanosine （8-OHdG） was determined by competitive ELISA. RESULTS： In CCh-treated group, the level of LPO in serum of liver and kidney was significantly increased compared to controls. The levels of GSH and enzyme activities of SOD, GSPx and GR in liver and kidney were significantly decreased in comparison with controls. In CCl4＋MA-treated group, the changes in the levels of LPO in serum of liver and kidney were not statistically significant compared to controls. The levels of SOD, GSPx and GR in liver and kidney were significantly increased in comparison with controls. There was a significant differ- ence in urinary excretion of 8-OHdG between the CCh- treated and MA-treated groups. CONCLUSION： Oxidative stress may be a major mechanism for the toxicity of CCh. MA has a protective effect against CCl4 toxicity by inhibiting the oxidative damage and stimulating GST activities. Thus, clinical application of MA should be considered in cases with carbon tetrachloride-induced injury.

Phenolics extract of Tetrapleura tetraptera fruit inhibits xanthine oxidase and Fe^2+-induced lipid peroxidation in the kidney,liver,and lungs tissues of rats in vitro

The phenolics composition and inhibitory activity of Tetrapleura tetraptera fruit extract on xanthine oxidase(XO)and Fe2+-induced lipid peroxidation in the kidney,liver and lungs tissues of rats were evaluated in vitro.Phenolics(flavonoids and phenolic acids)were quantified using reverse-phase high performance liquid chromatrography coupled with diode array detection(HPLC-DAD).The XO and Fe2+-induced lipid peroxidation inhibitory abilities of the extract were evaluated using spectrophotometric methods.The extract contained some flavonoids and phenolic acids,including catechin,epicatechin,rutin,quercetin,luteolin,apigenin;gallic,chlorogenic,caffeic and ellagic acids that are beneficial to health.The extract inhibited XO in the kidney,liver and lungs tissues in a dose-dependent manner.The half-maximal inhibitory concentrations(IC50)of the extract on XO from the tissues varied significantly(P<0.05),and were in the order of liver>kidney>lungs.The extract also inhibited Fe2+-induced lipid peroxidation in a dose-dependent pattern,having IC50 in the order of liver>lungs>kidney.T.tetraptera fruit extract could be a promising nutraceutical for preventing and managing hyperuricaemia and the associated disease conditions,due to its ability to inhibit XO;this bioactivity is attributable to combined effect of its flavonoids and phenolic acids.