Electroacupuncture protects the intestinal mucosal barrier in diarrhea-predominant Irritable Bowel Syndrome rats by regulating the MCs/Tryptase/PAR-2/MLCK pathway.

OBJECTIVE: The pathogenesis of diarrhea-predominant irritable bowel syndrome (IBS-D) is related to damage to the intestinal mucosal barrier function. Based on the Mast cell (MC)/Tryptase/Protease-activated receptor-2 (PAR-2)/Myosin light chain kinase (MLCK) pathway, this study explored the effect of electroacupuncture (EA) on IBS-D rats and its possible mechanism of protecting the intestinal mucosal barrier. METHODS: The IBS-D rat model was established by mother-offspring separation, acetic acid enema, and chronic restraint stress. The efficacy of EA on IBS-D rats was evaluated by observing the rate of loose stool (LSP) and the minimum volume threshold of abdominal withdrawal reflex (AWR) in rats. Mast cells and the ultrastructure of intestinal mucosa were observed by H&E staining, toluidine blue staining, and transmission electron microscopy. The expression levels of Tryptase, PAR-2, MLCK, zonula occludens-1 (ZO-1), and Occludin in rats were detected by ELISA, qRT-PCR, and western blot. RESULTS: After 7 days of intervention, compared to the IBS-D group, the loose stool rates of rats in IBS-D + EA group and IBS-D + ketotifen group were decreased (P < 0.01), the minimum volume thresholds of AWR were improved (P < 0.01), the inflammation of colon tissue decreased, the number of MCs were decreased (P < 0.01), the expression of Tryptase, PAR-2, and MLCK were lowered (P < 0.01, P < 0.05), and the expression of ZO-1 and Occludin were enhanced (P < 0.01, P < 0.05). Compared to the EA group, there was no significant difference in each index between the ketotifen groups (P > 0.05). CONCLUSION: EA has a good therapeutic effect on IBS-D rats. Regulating the MCs/Tryptase/PAR-2/MLCK pathway may be a mechanism to protect the intestinal mucosal barrier.

Effect of moxibustion on colonic low-grade inflammatory response in rats with diarrhea-predominant irritable bowel syndrome based on mast cell degranulation. / åŸºäºŽè‚¥å¤§ç»†èƒžè„±é¢—ç²’æŽ¢è®¨è‰¾ç¸å¯¹è ¹æ³»åž‹è‚ æ˜“æ¿€ç»¼åˆå¾å¤§é¼ ç»“è‚ ä½Žåº¦ç‚Žæ€§ååº”çš„å½±å“.

OBJECTIVES: To observe the effects of moxibustion on colonic mast cell degranulation and inflammatory factor expression in rats with diarrhea-predominant irritable bowel syndrome (IBS-D), and explore the potential mechanism of moxibustion in treating IBS-D. METHODS: Forty-five rat pups born from 5 healthy SPF-grade pregnant SD rats, with 8 rats were randomly selected as the normal group. The remaining 37 rats were intervened with maternal separation, acetic acid enema, and chronic restraint stress to establish the IBS-D model. The successfully modeled 32 rats were then randomly assigned to a model group, a ketotifen group, a moxibustion group, and a moxibustion-medication group, with 8 rats in each group. The rats in the ketotifen group were intervened with intragastric administration of ketotifen solution (10 mL/kg); the rats in the moxibustion group were intervened with suspended moxibustion on bilateral "Tianshu" (ST 25) and "Shangjuxu" (ST 37); the rats in the moxibustion-medication group were intervened with suspended moxibustion combined with intragastric administration of ketotifen solution. All interventions were administered once daily for 7 consecutive days. The diarrhea rate and minimum volume threshold of abdominal withdrawal reflex (AWR) were calculated before and after modeling, as well as after intervention. After intervention, colonic tissue morphology was observed using HE staining; colonic mucosal ultrastructure was examined by scanning electron microscopy; colonic mast cell ultrastructure was observed using transmission electron microscopy; mast cell degranulation was assessed by toluidine blue staining; serum and colonic levels of histamine, interleukin (IL)-1ß, IL-6, IL-1α, trypsin-like enzyme, and protease-activated receptor 2 (PAR-2) were measured by ELISA; the Western blot and real-time quantitative PCR were employed to evaluate the protein and mRNA expression of colonic IL-1ß, IL-6, IL-1α, trypsin-like enzyme, and PAR-2; the immunofluorescence was used to detect the positive expression of histamine, IL-1ß, IL-6, IL-1α, trypsin-like enzyme, and PAR-2 in the colonic tissue. RESULTS: Compared to the normal group, the rats in the model group exhibited extensive infiltration of inflammatory cells in colonic tissue, severe damage to the colonic mucosa, disordered arrangement of villi, reduced electron density, and a significant decrease in granule quantity within mast cells. The diarrhea rate and mast cell degranulation rate were increased (P<0.01), AWR minimum volume threshold was decreased (P<0.01); the serum and colonic levels of histamine, IL-1ß, IL-6, IL-1α, trypsin-like enzyme, and PAR-2 were elevated (P<0.01); the positive expression of histamine, as well as protein, mRNA and positive expression of IL-1ß, IL-6, IL-1α, trypsin-like enzyme, and PAR-2 in the colon were all elevated (P<0.01). Compared to the model group, the rats in the ketotifen group, the moxibustion group, and the moxibustion-medication group exhibited significantly reduced infiltration of inflammatory cells in colonic tissue, relatively intact colonic mucosa, orderly arranged villi, increased electron density, and an augmented number of mast cell granules; the diarrhea rate and mast cell degranulation rate were decreased (P<0.01), and AWR minimum volume threshold was increased (P<0.01); the serum and colonic levels of histamine, IL-1ß, IL-6, IL-1α, trypsin-like enzyme, and PAR-2 were reduced (P<0.01); the positive expression of histamine, as well as protein, mRNA and positive expression of IL-1ß, IL-6, IL-1α, trypsin-like enzyme, and PAR-2 in the colon were all decreased (P<0.01). Compared to the ketotifen group, the moxibustion group showed decreased serum levels of histamine, IL-6, and trypsin-like enzyme (P<0.01, P<0.05), as well as reduced colonic levels of IL-1ß and IL-6 (P<0.01, P<0.05); the protein expression of colonic IL-1ß, IL-1α, and PAR-2 was reduced (P<0.05), and the positive expression of colonic IL-1ß and trypsin-like enzyme was reduced (P<0.01, P<0.05). Compared to both the ketotifen group and the moxibustion group, the moxibustion-medication group exhibited decreased diarrhea rate and mast cell degranulation rate (P<0.01), an increased AWR minimum volume threshold (P<0.01), reduced serum and colonic levels of histamine, IL-1ß, IL-6, IL-1α, trypsin-like enzyme, and PAR-2 (P<0.01), decreased protein expression of colonic IL-1ß, trypsin-like enzyme, and PAR-2 (P<0.01, P<0.05), reduced mRNA and positive expression of colonic IL-1ß, IL-6, IL-1α, trypsin-like enzyme, and PAR-2 (P<0.01, P<0.05), and decreased positive expression of colonic histamine (P<0.01). CONCLUSIONS: Moxibustion on "Tianshu" (ST 25) and "Shangjuxu" (ST 37) might inhibit low-grade inflammatory reactions in the colon of IBS-D model rats. The mechanism may be related to the inhibition of histamine and trypsin-like enzyme secreted by mast cell, thereby reducing the expression of related inflammatory factors.

Moxibustion ameliorates visceral hypersensitivity by regulating hypothalamus-spinal cord-colon axis in rats with irritable bowel syndrome with diarrhea. / 基于下丘脑-脊髓-ç»“è‚ è½´æŽ¢è®¨è‰¾ç¸æ”¹å–„è ¹æ³»åž‹è‚ æ˜“æ¿€ç»¼åˆå¾å¤§é¼ å† è„é«˜æ•æ„Ÿçš„ä½œç”¨æœºåˆ¶.

OBJECTIVES: To observe the effect of moxibustion intervention on the hypothalamus-spinal cord-colon axis of rats with irritable bowel syndrome with diarrhea (IBS-D) and explore the mechanism of moxibustion in improving visceral hypersensitivity in rats with IBS-D. METHODS: A total of 36 SD rats were randomly divided into normal, model, and moxibustion groups, with 12 rats in each group. The IBS-D model was established by maternal separation + acetic acid stimulation + chronic restraint. Rats of the moxibustion group received bilateral moxibustion on "Tianshu" (ST25) and "Shangjuxu" (ST37) for 15 min, once a day for 7 consecutive days. The body weight, loose stool rate, and minimum threshold volume of abdominal withdrawal reflex (AWR) were measured before and after moxibustion intervention, respectively. The histopathological changes in the colon tissue were observed after HE staining. The number of colonic mucosal mast cells (MCs) was measured by toluidine blue staining. The activation of MCs was determined by tryptase positive expression level and examined by immunohistochemical staining. The content, protein and mRNA expression levels and positive expression levels of corticotropin releasing factor (CRF), substance P (SP), and calcitonin gene-related peptide (CGRP) in the hypothalamus, spinal cord and colon tissues were measured by ELISA, Western blot, real-time fluorescent quantitative PCR and immunofluorescence staining, respectively. RESULTS: Compared with the normal group, the loose stool rate was increased (P<0.01)；the body weight and minimum threshold volume of AWR were decreased (P<0.01)；the inflammatory infiltration of colon tissues was obvious；the number of MCs and positive expression level of tryptase in the colon tissue were increased (P<0.01)；the contents, positive expression le-vels, protein and mRNA expression levels of CRF, SP and CGRP in the hypothalamus, spinal cord and colon tissues were increased (P<0.01, P<0.05) in the model group. After the intervention, compared with the model group, all these indicators showed opposite trends (P<0.01, P<0.05) in the moxibustion group. CONCLUSIONS: Moxibustion can improve visceral hypersensitivity in rats with IBS-D, and its mechanism may be related to regulating the hypothalamic-spinal-colon axis to reduce the release of CRF, SP and CGRP, and thus to inhibite MC in colon tissue.

Hydrogen Peroxide Electrochemical Sensor Based on Ag/Cu Bimetallic Nanoparticles Modified on Polypyrrole.

Due to the strong oxidizing properties of H2O2, excessive discharge of H2O2 will cause great harm to the environment. Moreover, H2O2 is also an energetic material used as fuel, with specific attention given to its safety. Therefore, it is of great importance to explore and prepare good sensitive materials for the detection of H2O2 with a low detection limit and high selectivity. In this work, a kind of hydrogen peroxide electrochemical sensor has been fabricated. That is, polypyrrole (PPy) has been electropolymerized on the glass carbon electrode (GCE), and then Ag and Cu nanoparticles are modified together on the surface of polypyrrole by electrodeposition. SEM analysis shows that Cu and Ag nanoparticles are uniformly deposited on the surface of PPy. Electrochemical characterization results display that the sensor has a good response to H2O2 with two linear intervals. The first linear range is 0.1-1 mM (R2 = 0.9978, S = 265.06 µA/ (mM × cm2)), and the detection limit is 0.027 µM (S/N = 3). The second linear range is 1-35 mM (R2 = 0.9969, 445.78 µA/ (mM × cm2)), corresponding to 0.063 µM of detection limit (S/N = 3). The sensor reveals good reproducibility (σ = 2.104), repeatability (σ = 2.027), anti-interference, and stability. The recoveries of the electrode are 99.84-103.00% (for 0.1-1 mM of linear range) and 98.65-104.80% (for 1-35 mM linear range). Furthermore, the costs of the hydrogen peroxide electrochemical sensor proposed in this work are reduced largely by using non-precious metals without degradation of the sensing performance of H2O2. This study provides a facile way to develop nanocomposite electrochemical sensors.

[Moxibustion relieves colonic inflammation by up-regulating expression of miR-345-3p/miR-216a-5p and down-regulating NF-κB p65 in colonic tissue of rats with diarrhea-predominant irritable bowel syndrome].

OBJECTIVE: To observe the effect of moxibustion on the expression of miR-345-3p, miR-216a-5p and nuclear factor-κB p65(NF-κB p65) in colonic tissue of rats with diarrhea-predominant irritable bowel syndrome (IBS-D), so as to explore its anti-inflammatory mechanism in relieving IBS-D. METHODS: SD rats were randomly divided into normal control (n=12), model (n=12), moxibustion (n=12) and ammonium pyrrolidine dithiocarbamate (PDTC,n=12) groups. The IBS-D model was established by neonatal mother-child separation combined with acetic acid enema stimulation and chronic binding methods. The rats in the moxibustion group received moxibustion stimulation of "Tianshu"(ST25) and "Shangjuxu"(ST37) for 20 min, once a day, for 7 days, and those of the PDTC group received intraperitoneal injection of PDTC (50 mg·kg-1·d-1) once daily for 7 days. After the intervention, the body weight, loose stool rate and the minimum volume threshold of abdominal withdrawal reflex (AWR) were observed, and histopathological changes of colonic mucosa were observed by HE staining. The contents of interleukin-1ß (IL-1ß), interleukin-4 (IL-4), interleukin-6 (IL-6) and tumor necrosis factor α (TNF- α) in serum were measured by ELISA. The expression of miR-345-3p, miR-216a-5p and NF-κB p65 mRNA in the colon tissue were detected by quantitative real-time PCR, and the immunoactivities of IL-1ß, IL-6, TNF-α and NF-κB p65 in the colon tissue were determined by immunofluorescence histochemistry. RESULTS: Compared with the normal control group, the loose stool rate, contents of IL-1ß, IL-6 and TNF-α, experssion of NF-κB p65 mRNA and the immunoactivities of IL-1ß, IL-6, TNF-α and NF-κB p65 were significantly increased (P<0.01), whereas the body weight, minimum volume threshold of AWR, content of IL-4, and the relative expression of miR-345-3p and miR-216a-5p were remarkably decreased in the model group (P<0.01). In comparison with the model group, the loose stool rate, contents of IL-1ß, IL-6, TNF-α, expression of NF-κB p65 mRNA and the immunoactivities of IL-1ß, IL-6, TNF-α and NF-κB p65 were considerably down-regulated (P<0.01), while the content of IL-4 and the relative expressions of miR-345-3p and miR-216a-5p were obviously up-regulated in both moxibustion and PDTC groups (P<0.01, P<0.05). The content of IL-6 in serum was significantly lower in the PDTC group than in the moxibustion group (P<0.01). CONCLUSION: Moxibustion can reduce the level of intestinal inflammation and visceral hypersensitivity in IBS-D rats, which may be related to its functions in increasing the expression levels of miR-345-3p and miR-216a-5p and in inhibiting the expression of NF-κB p65, thus reducing the levels of inflammatory factors.

[Effect of moxibustion on immune function homeostasis in rats with diarrhea irritable bowel syndrome based on SCF/c-kit signaling pathway].

OBJECTIVE: To observe the effects of moxibustion on the stem cell factor (SCF)/tyrosine kinase receptor (c-kit) signaling pathway and immune function in rats with diarrhea irritable bowel syndrome (IBS-D), and to explore the mechanism of moxibustion for IBS-D. METHODS: Among 52 young rats born from 6 healthy pregnant SPF rats, 12 rats were randomly selected into the normal group, and the remaining 40 rats were treated with the three-factor combination method of maternal separation, acetic acid enema and chronic restraint stress to establish the IBS-D rat model. Thirty-six rats with successful IBS-D model were randomly divided into a model group, a moxibustion group, and a medication group, 12 rats in each group. The rats in the moxibustion group were treated with suspension moxibustion at "Tianshu" (ST 25) and "Shangjuxu" (ST 37); the rats in the medication group were treated with intragastric administration of rifaximin suspension (150 mg/kg). All the treatments were given once a day for 7 consecutive days. The body mass, loose stool rate (LSR), the minimum volume threshold when abdominal withdrawal reflex (AWR) scored 3 were measured before acetic acid enema (35 days old), after modeling (45 days old), and after intervention (53 days old). After intervention (53 days old), HE staining was used to observe the morphology of colon tissue, and spleen and thymus coefficients were measured; ELISA method was used to detect serum inflammatory factors (tumor necrosis factor a [TNF-a], interleukin [IL]-10, IL-8), T-lymphocyte subsets (CD+4, CD+8, CD+45), value of CD+4/CD+8 and immune globulin (IgA, IgG, IgM); real-time PCR method and Western blot method was used to detect the expression of SCF, c-kit mRNA and protein in colon tissue; immunofluorescence staining method were used to detect positive expression of SCF and c-kit. RESULTS: After intervention, compared with the normal group, in the model group, the body mass and the minimum volume threshold when AWR scored 3 were decreased (P<0.01), LSR, spleen and thymus coefficients, serum levels of TNF-α, IL-8, CD+4, CD+45, CD+4/CD+8, IgA, IgG, IgM were increased (P<0.01), serum IL-10 level and protein and mRNA expression of SCF and c-kit in colon tissue were decreased (P<0.01), and the positive expression of SCF and c-kit was decreased (P<0.01). Compared with the model group, in the moxibustion group and the medication group, the body mass and the minimum volume threshold when AWR scored 3 were increased (P<0.01, P<0.05), LSR, spleen and thymus coefficients, serum levels of TNF-α, IL-8, CD+4, CD+8, CD+45, CD+4/CD+8, IgA, IgG, IgM were decreased (P<0.01, P<0.05), serum IL-10 level and protein and mRNA expression of SCF and c-kit in colon tissue were increased (P<0.01), and the positive expression of SCF and c-kit was increased (P<0.01). Compared with the medication group, in the moxibustion group, the level of serum CD+4 was decreased (P<0.05), the value of CD+4/CD+8 was increased (P<0.01), and there was no significant difference in other indexes (P>0.05). The expression of SCF and c-kit mRNA was positively correlated with the minimum volume threshold when AWR scored 3 and IL-10 (P<0.01), and negatively correlated with remaining indexes (P<0.01, P<0.05). CONCLUSION: Moxibustion could reduce visceral hypersensitivity, improve symptoms of abdominal pain and diarrhea in IBS-D rats, and its mechanism may be related to up-regulation of the expression of SCF/c-kit signaling pathway and improvement of IBS-D immune function.

A highly active Z-scheme SnS/Zn2SnO4 photocatalyst fabricated for methylene blue degradation.

Herein, a highly active Z-scheme SnS/Zn2SnO4 photocatalyst is fabricated by a one-step hydrothermal route. The structure, composition, photoelectric and photocatalytic properties of the as-prepared photocatalysts are systematically researched. The results demonstrate that SZS-6 displays a good photocatalytic performance with an efficiency of 94.5% to degrade methylene blue (MB) under visible light irradiation (λ > 420 nm). And its degradation rate constant is up to 0.0331 min-1, which is 3.9 and 4.4 times faster than SnS and Zn2SnO4, respectively. The formation of a Z-scheme heterojunction facilitates the separation and transfer of charges, which improves the degradation of MB. The Z-scheme charge transfer pathway of the SnS/Zn2SnO4 photocatalyst is verified by the shifted peaks of the X-ray photoelectron spectroscopy (XPS) spectrum, the relative position of the bandgap, work function as well as free radical trapping experiments. The photocatalytic mechanism for the degradation of MB by SnS/Zn2SnO4 is proposed.

Improved Hydrogen Generation of Al-H2O Reaction by BiOX (X = Halogen) and Influence Rule.

In this work, three additives BiOX (BiOI, BiOBr, and BiOF) for Al-H2O reaction have been synthesized using chemical methods. SEM analysis shows that the structure of BiOF is nanoparticles, while BiOBr and BiOI have flower-like structures composed of nanosheets. Then, Al-BiOI, Al-BiOBr, and Al-BiOF composites have been prepared using the ball milling method. The effect of halogen ions on the performance of hydrogen generation from Al hydrolysis has been explored. The results indicate that the conversion yields of Al-BiOBr, Al-BiOI, and Al-BiOF for hydrogen generation are 96.3%, 95.3%, and 8.9%, respectively. In particular, the maximum hydrogen generation rate (MHGR) of Al-BiOI is as high as 3451.8 mL g-1 min-1, eight times higher than that of Al-BiOBr. Furthermore, the influence rule of BiOX (X = F, Cl, Br, and I) on Al-H2O reaction has been studied using density functional theory. The results illustrate that HI can be more easily adsorbed on the Al surface as compared with HF, HCl, and HBr. Meanwhile, the bond length between halogen ions and the Al atom increased in the order of F-, Cl-, Br-, and I-. Therefore, the dissociation of I- from the Al surface becomes easier and will expose more active sites to enhance the reaction activity of Al. In summary, the BiOI has the most favorable performance to Al-H2O reaction.

Correction: A highly active Z-scheme SnS/Zn2SnO4 photocatalyst fabricated for methylene blue degradation.

[This corrects the article DOI: 10.1039/D2RA05519H.].

Organic Crosslinked Polymer-Derived N/O-Doped Porous Carbons for High-Performance Supercapacitor.

Supercapacitors, as a new type of green electrical energy storage device, are a potential solution to environmental problems created by economic development and the excessive use of fossil energy resources. In this work, nitrogen/oxygen (N/O)-doped porous carbon materials for high-performance supercapacitors are fabricated by calcining and activating an organic crosslinked polymer prepared using polyethylene glycol, hydroxypropyl methylcellulose, and 4,4-diphenylmethane diisocyanate. The porous carbon exhibits a large specific surface area (1589 m2·g-1) and high electrochemical performance, thanks to the network structure and rich N/O content in the organic crosslinked polymer. The optimized porous carbon material (COCLP-4.5), obtained by adjusting the raw material ratio of the organic crosslinked polymer, exhibits a high specific capacitance (522 F·g-1 at 0.5 A·g-1), good rate capability (319 F·g-1 at 20 A·g-1), and outstanding stability (83% retention after 5000 cycles) in a three-electrode system. Furthermore, an energy density of 18.04 Wh·kg-1 is obtained at a power density of 200.0 W·kg-1 in a two-electrode system. This study demonstrates that organic crosslinked polymer-derived porous carbon electrode materials have good energy storage potential.

[Anti-inflammation effect of moxibustion for rats with diarrhea-predominant irritable bowel syndrome based on multiple miRNAs regulating NF-κB signal pathway].

OBJECTIVE: To observe the effect of moxibustion on the regulation of nuclear factor-kappa B (NF-κB) and inflammatory factors by multiple microRNAs (miRNAs) in rats with diarrhea-predominant irritable bowel syndrome (IBS-D), and to explore the anti-inflammatory mechanism of moxibustion on IBS-D. METHODS: Twelve of 52 newborn rats were randomly selected into a normal group. The remaining rats were made into IBS-D model. A total of 36 rats with successful model were randomly divided into a model group, a medication group and a moxibustion group, 12 rats in each group. The rats in the medication group were intraperitoneally injected with pyrrolidine dithiocarbamate (PDTC). The rats in the moxibustion group were treated with moxibustion at "Tianshu" (ST 25) and "Shangjuxu" (ST 37) for 20 min each time. All the intervention was given once a day for 7 days. Before and after modeling as well as after intervention, the body mass, loose stool rate and the minimum volume threshold of abdominal withdrawal reflex (AWR) were measured. After intervention, the contents of serum tumor necrosis factor α (TNF-α), interleukin (IL)-1ß and IL-8 were detected by ELISA method; the morphology of colon tissues was observed by HE staining, and the expressions of miR-155, miR-125b, miR-29b, miR-31, miR-18a and NF-κB p65 mRNA in colon tissues were detected by real-time PCR. The expressions of NF-κB p65, TNF-α, IL-1ß and IL-8 protein in colon tissues were detected by immunofluorescence. RESULTS: After modeling, the body mass and the minimum volume threshold of AWR in the model group were lower than those in the normal group (P<0.01); the rates of loose stool in the model group were higher than those in the normal group (P<0.01); after intervention, in the model group, the inflammatory infiltration of colon tissues was obvious, and the serum levels of TNF-α, IL-1 ß, IL-8 were higher than those in the normal group (P<0.05); the expression of miR-155, miR-125b, miR-29b, miR-31, miR-18a and NF-κB p65 mRNA in colon tissues was higher than that in the normal group (P<0.05); the protein expression of NF-κB p65, TNF-α, IL-1ß, IL-8 was also higher than that in the normal group (P<0.01). After intervention, the body mass and the minimum volume threshold of AWR in the medication group and the moxibustion group were both higher than those in the model group (P<0.05); the loose stool rate in the medication group and the moxibustion group were lower than those in model group (P<0.05); the inflammatory cells infiltration in the colon tissues was less, the serum levels of TNF-α, IL-1ß and IL-8 as well as the protein expression of NF-κB p65, TNF-α, IL-1ß and IL-8 in the colon tissues in the medication group and the moxibustion group were lower than those in the model group (P<0.05, P<0.01). The expression of miR-125b, miR-31, miR-18a and NF-κB p65 mRNA in the medication group were lower than those in the model group (P<0.05). The expression of miR-155, miR-125b, miR-29b, miR-31, miR-18a and NF-κB p65 mRNA in the moxibustion group were lower than those in the model group (P<0.05). The miR-155, miR-125b, miR-29b, miR-31, miR-18a were positively correlated with NF-κB p65 mRNA (0

A bivalent cyclic RGD-siRNA conjugate enhances the antitumor effect of apatinib via co-inhibiting VEGFR2 in non-small cell lung cancer xenografts.

The vascular endothelial growth factor receptor 2 (VEGFR2) is considered to be a pivotal target for anti-tumor therapy against angiogenesis of non-small cell lung cancer (NSCLC). However, effective and low-toxicity targeted therapies to inhibit VEGFR2 are still lacking. Here, biRGD-siVEGFR2 conjugate comprising murine VEGFR2 siRNA and [cyclo(Arg-Gly-Asp-D-Phe-Lys)-Ahx]2-Glu-PEG-MAL (biRGD) peptide which selectively binds to integrin αvß3 receptors expressing on neovascularization endothelial cell was synthesized. The anti-tumor activity and renal toxicity of biRGD-siVEGFR2 or its combination therapy with low-dose apatinib were investigated on NSCLC xenografts. The immunogenicity of biRGD-siVEGFR2 was also evaluated in C57BL/6J mice. In vivo, intravenously injected biRGD-siVEGFR2 substantially inhibited NSCLC growth with a marked reduction of vessels and a down-regulation of VEGFR2 in tumor tissue. Furthermore, biRGD-siVEGFR2 in combination with low-dose apatinib achieved powerful anti-tumor effect with less nephrotoxicity compared with the regular dose of apatinib. Besides, no obvious immunogenicity of biRGD-siVEGFR2 was found. These findings demonstrate that biRGD-siVEGFR2 conjugate can be used as a new candidate for the treatment of NSCLC and its combination therapy with apatinib may also provide a novel strategy for cancer treatment in clinic.

Protective effect of Gelofusine against cRGD-siRNA-induced nephrotoxicity in mice.

Based on successful targeting to the αvß3 integrin of cyclic arginine-glycine-aspartic acid (cRGD), cRGD-conjugated small interfering RNA (siRNA) exhibits tumor targeting and has become a new treatment strategy for solid tumors. However, the nephrotoxicity caused by its renal retention limits its clinical application. Here, we evaluated the protective effect of Gelofusine against cRGD-conjugated siRNA-induced nephrotoxicity in mice. Male Kunming mice (six per group) were either co-injected with Gelofusine and cRGD-siRNA or injected with cRGD-siRNA alone. After administration of these treatments five times, creatinine and blood urea nitrogen (BUN) levels were determined. Hematoxylin-eosin staining (HE staining) and transferase dUTP nick end labeling (TUNEL) analysis were used to compare the difference in renal damage between the groups. Additionally, fluorescence imaging was used to observe the distribution of cRGD-siRNA in vivo. The group co-injected with Gelofusine and cRGD-siRNA displayed lower creatinine and BUN levels than the cRGD-siRNA-alone group and showed less renal damage upon HE staining and TUNEL analysis. Gelofusine decreased the retention time and accelerated the elimination of cRGD-siRNA from the organs, as observed in the fluorescence images. These data indicate that Gelofusine significantly increased the excretion of cRGD-conjugated siRNA and reduced the associated renal damage.

[Small interfering RNA-mediated programmed cell death-ligand 1 silencing in human glioma cells enhances human CD8+ T lymphocyte cytotoxicity in vitro].

OBJECTIVE: To investigate the effect of small interfering RNA (siRNA)-mediated silencing of programmed cell deathligand 1 (PD-L1) in human glioma cells on the cytotoxicity of human CD8+T lymphocytes against the modified tumor cells. METHODS: A siRNA sequence targeting PD-L1 gene was designed and transfected into human glioma U87 MG cells via lipofectamine 2000, and the gene silencing effect was validated using RT-qPCR, Western blotting, and flow cytometry. The transfected cells were co-cultured with human CD8+T lymphocytes, and the apoptosis of the tumor cells was analyzed with flow cytometry. RESULTS: The siRNA sequence showed strong PD-L1 gene-silencing effect at both mRNA and protein levels in U87 MG cells. Compared with the control cells, the transfected U87 MG cells showed significantly increased vulnerability to the cytotoxicity of human CD8+T cells and an obvious reduction of proliferative activity in the co-culture (P < 0.05). CONCLUSIONS: Transfection of human glioma U87 MG cells with the specific siRNA targeting PD-L1 obviously enhances the toxicity of human T lymphocytes in the co-culture.

A tumor-targeting cRGD-EGFR siRNA conjugate and its anti-tumor effect on glioblastoma in vitro and in vivo.

The epidermal growth factor receptor (EGFR) is an important anti-tumor target. The development of novel molecular-targeted anti-tumor drugs that can target the interior of tumor cells and specifically silence EGFR expression is valuable and promising. In this work, a promising anti-tumor conjugate comprising methoxy-modified EGFR siRNA and cyclic arginine-glycine-aspartic acid (cRGD) peptides, which selectively bind to αvß3 integrins, was synthesized and examined. To prepare cRGD-EGFR siRNA (cRGD-siEGFR), cRGD was covalently conjugated to the 5'-end of an siRNA sense strand using a thiol-maleimide linker. The cellular uptake and cytotoxicity of cRGD-siEGFR in vitro were tested using an αvß3-positive U87MG cell line. In vivo bio-distribution, anti-tumor activity, immunogenicity and toxicity were investigated in a nude mouse tumor model through repeated i.v. administration of cRGD-siEGFR (7 times over a 48 h interval). Analyses of in vitro data showed that cRGD-siEGFR silenced EGFR expression effectively, with high tumor targeting ability. Administration of cRGD-siEGFR to tumor-bearing nude mice led to significant inhibition of tumor growth, obvious reduction of EGFR expression and down-regulation of EGFR mRNA and protein in tumor tissue. Furthermore, serum biochemistry and pathological section evaluation did not indicate any serious toxicity of cRGD-siEGFR in vivo. cRGD-siEGFR is likely a promising candidate with high targeting ability, substantial anti-tumor effects and low toxicity in vitro and in vivo.

[Effects of serum starvation on cell cycle synchronization in primary human umbilical vein endothelial cells].

OBJECTIVE: To investigate the optimal starvation conditions of human umbilical vein endothelial cells (HUVECs) and establish a highly efficient and stable method for separating HUVECs. METHODS: HUVECs harvested from human umbilical cords by digestion with 0.1% collagenase II for 15 min were cultured in endothelial culture medium (ECM) containing 5% fetal bovine serum (FBS), 1% endothelial cell growth factor (ECGS) and 1% penicillin/streptomycin solution(P/S) at 37 degrees celsius; in 5% CO2. The cells were observed for cell morphology under an inverted microscope and identified with immunofluorescence assay. The purity of HUVECs was detected using flow cytometry (FCM). The cell cycles of HUVECs cultured in the presence of 0, 0.1%, 0.5%, and 1% FBS for 0, 6, 12, 18, and 24 h were analyzed with flow cytometry. RESULTS: s The purity of HUVECs harvested by digestion with 0.1% collagenase II reached 99.67%. The primary HUVECs showed a cobblestone or volute appearance in vitro. Immunocytochemistry showed that HUVECs highly expressed VIII-related antigen. Cell culture in the presence of different concentrations of FBS for 6 h resulted in 70% G0/G1 phase cells, which increased to 80%-90% at 12 h of cell culture, and further to around 95% at 18 and 24 h. CONCLUSION: Digestion with 0.1% collagenase II can obtain high-purity primary HUVECs. Culturing HUVECs in serum-free medium for 12 h can result in a high purity (over 80%) of G0/G1 phase cells.