Maximakinin reduced intracellular Ca2+ level in vascular smooth muscle cells through AMPK/ERK1/2 signaling pathways.

We detect the antihypertensive effects of maximakinin (MK) on renal hypertensive rats (RHRs) and further research the influence of MK on vascular smooth muscle cells (VSMCs) to explore its hypotensive mechanism. The effects of MK on arterial blood pressure were observed in RHRs. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide (MTT) assays were performed to detect the effect of MK on VSMC viability. Western blot and flow cytometry were used to investigate the influence of MK on intracellular Ca2+ levels and protein expression changes in VSMCs. In addition, specific protein inhibitors were applied to confirm the involvement of Ca2+-related signaling pathways induced by MK in VSMCs. MK showed a more significant antihypertensive effect than bradykinin in RHRs. MK significantly decreased intracellular Ca2+ concentrations. Furthermore, MK significantly induced the phosphorylation of signaling molecules, including extracellular signal-regulated kinase 1/2 (ERK1/2), P38, AMP-activated protein kinase (AMPK) and Akt in VSMCs. Moreover, only ERK1/2 inhibitor U0126 and AMPK inhibitor Compound C completely restored the decreased intracellular Ca2+ level induced by MK, and further research demonstrated that AMPK functioned upstream of ERK1/2 following exposure to MK. Finally, HOE-140, an inhibitor of the bradykinin B2 receptors (B2Rs), was applied to investigate the potential targets of MK in VSMCs. HOE-140 significantly blocked the AMPK/ERK1/2 pathway induced by MK, suggesting that the B2Rs might play an important role in MK-induced AMPK and ERK1/2 activation. MK significantly reduces blood pressure in RHRs. MK exerts its antihypertensive effect by activating the B2Rs and downstream AMPK/ERK1/2 pathways, leading to significantly reduced Ca2+ levels in VSMCs.

The antihypertensive effect of MK on spontaneously hypertensive rats through the AMPK/Akt/eNOS/NO and ERK1/2/Cx43 signaling pathways.

We investigated the antihypertensive effects of maximakinin (MK) on spontaneously hypertensive rats (SHRs). The effects of MK on arterial blood pressure in SHRs were observed, and flow cytometry and 4,5-diaminofluorescein-2 staining were used to examine MK-induced nitric oxide (NO) release in human umbilical vein endothelial cells (HUVECs). Western blotting was used to analyze the effects of MK on the expression of AMP-activated protein kinase (AMPK), Akt, Connexin 43, ERK1/2, p38, and p-eNOS in HUVECs. The results showed that MK induced a more significant antihypertensive effect on SHRs than bradykinin (BK). MK induced significant increases in endothelial nitric oxide synthase (eNOS) phosphorylation and NO release in HUVECs. MK also significantly increased the phosphorylation of Akt and AMPK in HUVECs. The AMPK inhibitor compound C blocked the effect of MK on the generation of NO. MK induced the phosphorylation of ERK1/2, p38, and Connexin 43. The expression of p-Connexin 43 was significantly decreased in the presence of the ERK1/2 inhibitor U0126 but not the p38 inhibitor SB203580. The effects of MK on the phosphorylation of AMPK and ERK1/2 were significantly decreased by the BK B2 receptor inhibitor HOE-140. In summary, MK can significantly reduce blood pressure in SHRs. The antihypertensive effect might be mediated through the activation of the BK B2 receptor, while the downstream AMPK/PI3K/Akt/eNOS/NO and ERK1/2/Connexin 43 signaling pathways play additional roles.

A Cannabinoid-1 Receptor Antagonist MJ08 with Different Effects in Stomach and Small Intestine.

Background:To investigate the inverse agonistic effect of a novel type 1 cannabinoid (CB1) receptor antagonist, MJ08, on the gastrointestinal tract (GIT).Methods: In vivo, carbon propulsion within the stomach of mice was undertaken to investigate the effects of MJ08. In vitro, the effects of MJ08 were investigated on the contraction of smooth muscle on the isolated gastric fundus, gastric body, duodenum, jejunum, and ileum.Results:Western blotting results showed that MJ08 (0.62 mg/kg body weight) reversed WIN55,212-2 (1.0 mg/kg)-induced reduction of carbon transit. MJ08 (1.25, 2.5 mg/kg) stimulated carbon transit dose dependently, demonstrating an inverse agonistic effect. In vitro experiments showed that the expression of MJ08 increased the contraction of small intestine, and that its inverse agonistic effect was significantly stronger than that of SR141716A, but no effect was noted on the gastric body. Western blotting showed that the MJ08 increased the expression of CB1 receptor in different GIT segments.Conclusion:MJ08 is not only an antagonist but also an inverse agonist of the CB1 receptor. MJ08 and SR141716A can enhance motility in the small intestine and increase the expression of CB1 receptor in the small intestine.

[Influence of different filling method-related sperm counting chambers and structural factors of disposable chambers on sperm motility].

Objective: To evaluate the effects of different filling method-related sperm counting chambers and the structural factors of Leja counting chambers on sperm motility using computer-assisted sperm analysis (CASA). METHODS: Using drop-filled Makler, capillary-loaded Leja and structurally modified Leja sperm counting chambers, we measured sperm concentration, the percentages of progressively motile sperm (PMS) and non-progressively motile sperm (NPMS), total sperm motility, curvilinear velocity (VCL), average path velocity (VAP), straight line velocity (VSL), beat-cross frequency (BCF), linearity (LIN), wobble (WOB) and straightness (STR) in the semen samples of 76 males by CASA and compared them between different chambers. RESULTS: The drop-filled Makler sperm counting chamber achieved remarkably higher PMS, NPMS, total sperm motility, VCL and VAP than the Leja chambers (P < 0.05). There were no statistically significant differences in VSL, BCF, LIN, WOB and STR between the Makler and Leja chambers (P > 0.05), or in sperm concentration, PMS, NPMS and total sperm motility between the capillary-loaded and structurally modified Leja counting chambers (P > 0.05). The ground edge and thickness of the coverslip of the Leja counting chamber produced no significant inference on the kinetic sperm parameters (P > 0.05). CONCLUSIONS: The drop-filled sperm counting chamber achieves significantly higher sperm motility and kinetic parameters than the capillary-loaded Leja chamber. The structural factors such as the ground edge and thickness of the coverslip of the Leja counting chamber do not influence the analysis of sperm parameters.

Silibinin induced apoptosis of human epidermal cancer A431 cells by promoting mitochondrial NOS.

The antitumor effects of silibinin are of increasing interest, though its mechanism is not yet clear. The goal of this study was to clarify the mechanism of silibinin-induced cell death in the A431 human epidermoid carcinoma cell line. We used a cell viability assay, flow cytometry, nitric oxide (NO) assay, and western blotting to examine relationships between silibinin, NO generation and apoptosis in A431 cells. Silibinin inhibited A431 cell growth in a dose-dependent manner, inducing mitochondrial damage, and apoptosis at a high dose. At the same time, high dose silibinin increased NO levels in A431 cells and the endothelial nitric oxide synthase (eNOS) inhibitor NG-nitro-L-arginine methylester (L-NAME) attenuated silibinin-induced cell growth inhibition. By western blotting, silibinin caused increased eNOS phosphorylation in the mitochondria. The AMP-activated protein kinase inhibitor compound C significantly decreased p-eNOS expression, while blocking eNOS did not affect p-AMPK levels, suggested that AMPK acted upstream of eNOS. This study showed that silibinin increased NO levels in A431 cells by activating the AMPK-eNOS pathway, leading to mitochondrial dysfunction and apoptosis. In this mechanism of action, mitochondrial eNOS played an important role. The results provided new understanding of the functions of intracellular NO.

Synthesis, physicochemical characterization and pharmacological investigation of indolacin-5-fluorouracil-1-ylmethyl ester.

The objective of this work is to synthesize indolacin-5-fluorouracil-1-ylmethyl ester and the structure was confirmed by means of UV, IR, 1H-NMR, 13C-NMR and mass spectrometry. The physicochemical parameters of melting point, solubility, apparent partition coefficient were investigated. S180 sarcoma, H22 hapatitic cancer and Lewis-transplanted mice were used to evaluate the anti-tumor activity of indolacini-5-fluorouracil-1-ylmethyl ester compared with 5-fluorouracil in vivo. Anti-inflammatory and analgesic activities were evaluated in mice. The inhibitory ratio of indolacini- 5-fluorouracil-1-ylmethyl ester is comparative to that of 5-fluorouracil. This study indicates that 5-fluorouracil-1-ylmethyl ester may represent a new anticancer predrug of 5-fluorouracil to produce a combined effect of indolacin and 5-fluorouracil for cancer therapy.

[Sperm sorting based on the imitation of the physiological process on the microfluidic chip].

OBJECTIVE: To establish a new method for sperm sorting by imitating the physiological process of sperm-cervical mucus interaction on the microfluidic chip. METHODS: We designed a microfluidic chip to imitate the physiological process of natural sperm sorting in the microchannel based on the interaction between sperm and cervical mucus, and obtained motile sperm after the interaction. Meanwhile, we established an integrated real-time sperm detection reservoir on this chip to determine sperm parameters using the computer-assisted sperm analysis system. We analyzed 30 samples using both microfluidic and swim-up methods, and compared the results with those obtained before sorting. RESULTS: The rate of grade a + b sperm, the rate of morphologically normal sperm, straight-line velocity (VSL), average path velocity (VAP) and straightness (STR) were (29.78 +/- 11.24)%, (8.00 +/- 5.19)%, (18.89 +/- 4.90) microm/s, (26.84 +/- 5.13) microm/s and (70.15 +/- 7.61)%, respectively, before sorting, (71.65 +/- 11.18)%, (14.95 +/- 6.79)%, (24.14 +/- 5.95) microm/s, (32.61 +/- 6.36) microm/s and (73.87 +/- 9.34)%, respectively, after swim-up sorting, and (92.37 +/- 6.33)%, (23.33 +/- 7.67)%, (34.03 +/- 16.78) microm/s, (38.73 +/- 16.40) microm/s and (84.91 +/- 12.56)%, respectively, after sorting on the microfluidic chip. The sperm parameters obtained before sorting showed statistically significant differences from those obtained on the chip (P < 0.01) and by the swim-up method (P < 0.05). CONCLUSION: Imitation of the physiological interaction between sperm and cervical mucus on the microfluidic chip helped the realization of both the natural sorting and real-time analysis of sperm. The quality of the sperm sorted on the microfluidic chip is significantly better than that of the sperm before sorting and sorted by the swim-up method. This has prepared the ground for imitating the fertilization process under the physiological condition on the microfluidic chip.

[Development of a GeXP based multiplex RT-PCR assay for simultaneous differentiation of nine human hand food mouth disease pathogens].

A multiplex RT-PCR assay based on GeXP system was developed in order to detect simultaneously human enterovirus 71 (EV71) and coxsackievirus A16 (CVA16) and other coxsackieviruses (CVA4, 5, 9 and 10, CVB1, 3 and 5). Enterovirus detection was performed with a mixture of 12 pairs of oligonucleotide primers including one pair of published primers for amplifying all known pan-enterovirus genomes and eleven primer pairs specific for detection of the VP1 genes of EV71, C A16, CVA4, CVA5, CVA9, CVA10, CVB1, CVB3 and CVB5, respectively. The specificity of multiplex RT-PCR system was examined using enterovirus cell cultures and positive strains identified previously from hand-foot-and-mouth disease (HFMD) patients. Serial dilution of titrated EV71 and C A16 cell cultures and in vitro transcripted RNA of enterovirus VP1 regions were used to detect the sensitivity of the multiplex RT-PCR system. The limit of detection for this multiplex RT-PCR system was 10(0.5) TCID50/microL for EV71 and C A16 cell cultures and 1000 copies for in vitro transcripted RNA of nine viruses per assay. This multiplex RT-PCR assay is a rapid, sensitive and specific assay for the diagnosis of common enterovirus infection in cases of HFMD outbreak and is also potentially useful for molecular epidemiological investigation.

[Effects of a microfluidic sperm sorter on sperm routine parameters and DNA integrity].

OBJECTIVE: To investigate the effects of a microfluidic sperm sorter on the routine parameters and DNA integrity of human sperm. METHODS: We divided 40 semen samples into two aliquots and performed sperm sorting using a self-made polydimethylsiloxane microfluidic sperm sorter and the swim-up method, respectively. Then we evaluated and compared the effects of these two methods on the sperm routine parameters and DNA integrity by computer-assisted sperm analysis and sperm chromatin dispersion test. RESULTS: After processing, sperm motility, normal morphology and tail hypoosmotic swelling rate were significantly improved, while sperm DNA damage remarkably decreased (P < 0.01). The microfluidic sperm sorter achieved a significantly lower rate of sperm DNA damage than the swim-up method ([ 8.4 +/- 5.8 ]% vs [16.4 +/- 9.2] %, P < 0.01), but no statistically significant differences were found in all other parameters between the two methods. CONCLUSION: High-quality sperm with less DNA integrity damage could be obtained in sperm sorting with the microfluidic sperm sorter.

[Combined effect of anti-vascular endothelial growth factor antibody and recombinant human TRAIL on inducing apoptosis of leukemia K562 cells].

The objective of this study was to investigate the synergistic effect of soluble human recombinant tumor necrosis factor related apoptosis inducing ligand (TRAIL) protein combined with anti-vascular endothelial growth factor (anti-VEGF) antibody on inducing apoptosis of leukemia K562 cells. The inhibitory rates and apoptotic rates of K562 cells treated with TRAIL and anti-VEGF antibody alone and their combination for 48 hours were examined by CCK-8 assay and flow cytometry respectively. The results indicated that the apoptotic rates of K562 cells induced with 75, 100 and 150 ng/ml TRAIL after culture for 48 hours were (4.26±0.67)%, (8.91±0.55)% and (11.71±0.78)% respectively. The apoptotic rates of K562 cells induced with 2.5, 5 and 7.5 µg/ml anti-VEGF antibody after culture for 48 hours were (3.95±0.69)%, (7.98±0.74)% and (10.26±0.83)% respectively. The apoptotic rates of K562 cells treated with combination use of 2.5 µg/ml anti-VEGF antibody and 75 ng/ml TRAIL, 5 µg/ml anti-VEGF antibody and 100 ng/ml TRAIL, and 7.5 µg/ml anti-VEGF antibody and 150 ng/ml TRAIL for 48 hours were (22.16±0.93)%, (36.32±1.31)% and (49.19±0.71)% respectively. The combined use of above mentioned agents induced significantly higher apoptosis and cytotoxicity than that of TRAIL or anti-VEGF antibody alone (p<0.05). It is concluded that the combination use of TRAIL and anti-VEGF antibody can significantly increase the sensitivity of K562 cells to apoptosis.

Analgesic activity of myricetin isolated from Myrica rubra Sieb. et Zucc. leaves.

Myrica rubra Sieb. et Zucc. leaves are commonly used as an astringent, antidiarrheic, and analgesics in folk medicine in China. In the present study, the analgesic activity of myricetin, a major compound in Myrica rubra Sieb. et Zucc. leaves was evaluated in vivo. The analgesic effect of myricetin was tested by a serial of models, such as acetic acid-induced writhing response, formalin-induced paw licking and hot plate test. The sedative activity was evaluated by pentobarbital-induced sleep time. Platelet aggregation induced by collagen and arachidonic acid was also performed in vitro. Myricetin showed a significant inhibition on chemical nociceptive models such as the acetic acid-induced writhing response and the licking time on the late phase in the formalin test in a dose-dependent manner, but did not manifest a signicant effect in hot plate test. Myricetin was also not able to increase the sleeping time induced by pentobarbital, which further indicated that the analgesic effect of myricetin was unrelated to sedation. In addition, myricetin inhibited the content of PGE2 in the peritoneal fluid and platelet aggregation induced by collagen and arachidonic acid in vitro. These results collectively demonstrated that myricetin possessed potent analgesic activity, which was related with peripheral analgesia, but, not with the opioid system. Myricetin may be a potent COX-1 inhibitor with anti-platelet activity.

Neuroprotection of ginsenoside Re in cerebral ischemia-reperfusion injury in rats.

In the present study, we have investigated the neuroprotective potential of ginsenoside Re (Re) in the middle cerebral artery occlusion model in Sprague-Dawley rats. Adult male Sprague-Dawley rats were treated with Re (5, 10 or 20 mg kg(- 1), P.O. for 7 days, once a day) prior to occlusion. There was a significant increase in the neurological symptoms in ischemic animals as compared with the sham group animals. These effects were attenuated by 10 and 20 mg kg(- 1) Re, P.O. There was a significant increase in the level of malondialdehyde (MDA) in ischemic animals indicating oxidative stress. An elevated level of MDA in ischemic animals was reduced by 10 and 20 mg kg(- 1) Re, P.O., respectively. It was observed that Re significantly decreased mitochondrial swelling, thereby preventing the reduction of H(+)-ATPase activity. This study demonstrates the neuroprotective potential of Re in cerebral ischemia-reperfusion injury in rats.

Protective effect of ginsenoside-Re against cerebral ischemia/reperfusion damage in rats.

To investigate the protective effect of ginsenoside Re (Re) against cerebral ischemia-reperfusion injury, adult male Wistar rats weighing 250-300 g were subjected to either sham surgery or middle cerebral artery occlusion (MCAO) for 2 h of brain ischemia and 2 h reperfusion. A fluorescence polarization assay was carried out for membrane fluidity of brain mitochondria. Lipid peroxidation [malondiadehyde (MDA) formation], superoxide dismutase (SOD) and glutathion peroxidase (GSH-Px) of rat brain were estimated by fluorometric methods. It was observed that Re (5, 10, 20 mg kg-1 p.o. pretreatment for 7 d, once a day) significantly improved the fluidity of mitochondrial membranes as demonstrated by a reduction of average microviscosity, ameliorated lipid peroxidation by raising the activities of SOD and GSH-Px, and reduced the content of MDA in rat brain. This study demonstrated a direct protective effect of Re against cerebral ischemia-reperfusion injury.

Modification of a poly(methyl methacrylate) injection-molded microchip and its use for high performance analysis of DNA.

Inexpensive and permanently modified poly(methyl methacrylate)(PMMA) microchips were fabricated by an injection-molding process. A novel sealing method for plastic microchips at room temperature was introduced. Run-to-run and chip-to-chip reproducibility was good, with relative standard deviation values between 1-3% for the run-to-run and less than 2.1% for the chip-to-chip comparisons. Acrylonitrile-butadiene-styrene (ABS) was used as an additive in PMMA substrates. The proportions of PMMA and ABS were optimized. ABS may be considered as a modifier, which obviously improved some characteristics of the microchip, such as the hydrophilicity and the electro-osmotic flow (EOF). The detection limit of Rhodamine 6G dye for the modified microchip on the home-made microchip analyzer showed a dramatic 100-fold improvement over that for the unmodified PMMA chip. A detection limit of the order of 10(-20) mole has been achieved for each injected psiX-174/HaeIII DNA fragment with the baseline separation between 271 and 281 bp, and fast separation of 11 DNA restriction fragments within 180 seconds. Analysis of a PCR product from the tobacco ACT gene was performed on the modified microchip as an application example.

Highly sensitive determination of the methylated p16 gene in cancer patients by microchip electrophoresis.

The p16 tumor suppressor gene is inactivated by promoter region hypermethylation in many types of tumor. Recent studies showed that aberrant methylation of the p16 gene is an early event in many tumors, especially in lung cancer, and may constitute a new biomarker for early detection and monitoring of prevention trials. We detected tumor-associated aberrant hypermethylation of the p16 gene in plasma and tissue DNA from 153 specimens using a modified semi-nested methylation-specific PCR (MSP) combining plastic microchip electrophoresis or slab gel electrophoresis, respectively. Specimens were from 79 lung cancer patients, 15 abdominal tumor patients, 30 positive controls and 30 negative controls. The results showed that the positive rate obtained by microchip electrophoresis was more than 26.6% higher and the same specificity was kept when compared with slab gel electrophoresis. The microchip electrophoresis can rapidly and accurately analyze the PCR products of methylated DNA and obviously improve the positive rate of diagnosis of cancer patients when compared with gel electrophoresis. This method with the high assay sensitivity might be used for detection of methylation of p16 gene and even to facilitate early diagnosis of cancer patients.

Effect of (3,5,6-trimethylpyrazin-2-yl)methyl 2-[4-(2-methylpropyl)phenyl]propanoate (ITE), a newly developed anti-inflammatory drug, on type II collagen-induced arthritis in mice.

The effect of (3,5,6-trimethylpyrazin-2-yl)methyl 2-[4-(2-methylpropyl)phenyl]propanoate (ITE) on type II collagen (CII)-induced arthritis in mice was studied. Mice were immunized twice with CII, ITE being given orally once a day for 40 d after the 1st immunization. Clinical assessment showed that ITE had no effect on the day of onset of arthritis but did lowered the incidence rate of arthritis and the arthritis score. And ITE had a marked suppressive effect on the mouse hind paw edema induced by CII. ITE suppressed the delayed-type mouse ear skin reaction to CII but had no effect on the level of serum anti-CII antibodies. These results suggest that ITE inhibits the development of CII-induced arthritis in mice by suppressing delayed-type hypersensitivity to CII.