[Short-term efficacy of three root canal filling methods in endodontic treatment of chronic periapical inflammation].

PURPOSE: To provide a reference basis for clinical selection of a reasonable and effective root canal treatment by comparing the short-term clinical efficacy of three root canal filling methods in the treatment of chronic periapical inflammation. METHODS: One hundred and twenty patients with chronic periapical inflammation who received root canal filling between October 2019 and October 2020 were randomly divided into 3 groups, with 40 patients in each group. All patients received root canal filling, group A was filled with iRoot SP paste by matched-taper single cone obturation technique, group B was filled with AH-plus paste by warm vertical condensation, and group C filled with AH-plus paste by cold lateral condensation. Root canal filling time in the three groups was calculated, pain score 24 h after treatment was determined using visual analogue scale/score(VAS), and periapical index(PAI) was used to evaluate radiographs. SPSS 22.0 statistical software was applied for data analysis. RESULTS：Root canal filling times in the three groups were (75.50±7.44) s in group A, (85.38±3.46) s in group B and (102.33±3.32) s in group C, the differences were statistically significant (P<0.05); the incidence of postoperative pain in the three groups was 25% in group A, 25% in group B and 32.5% in group C, the difference was not statistically significant(P>0.05). There was no significant difference between group A and group B, but significant difference existed between group A, group B and group C. The results of comparison of PAI scores showed a time effect was F=498.93, P<0.001, suggesting significant difference in total PAI scores at different time points; a group effect was F=0.91, P=0.406, suggesting no significant difference in total PAI scores of the 3 groups; an interaction effect of time and group was F=0.44, P=0.777, suggesting that there was no significant difference in total PAI scores of the 3 groups at the time points. The total effective rate at 3 and 12 months was 97.5%, 97.3% in group A, 97.5%, 97.2% in group B and 90%, 91.9% in group C, the difference was not statistically significant(P>0.05). CONCLUSIONS： Compared with the other 2 root canal filling methods, the iROOT SP paste matched-taper single cone obturation technique is clinically effective in terms of time saving and increasing the comfort of the patients' visit.

Expression Pattern of G-Protein-Coupled Estrogen Receptor in Myometrium of Uteri with and without Adenomyosis.

OBJECTIVE: To compare the expression of G-protein-coupled estrogen receptor (GPER) in the junctional zone and outer myometrium of the proliferative and secretory phases of women with and without adenomyosis. METHODS: A total of 76 women were included in this study, 42 with adenomyosis (proliferative phase, n = 23; secretory phases, n = 19) and 34 controls (proliferative phase, n = 16; secretory phases, n = 18). Protein and total RNA were extracted from the junctional zone (JZ) and outer myometrium (OM). GPER protein and mRNA expression levels were evaluated by the use of western blotting and real-time quantitative polymerase chain reaction (RT-qPCR). RESULTS: The expression of GPER protein and mRNA in women with adenomyosis was significantly higher than that of control subjects, both in the junctional zone and in the outer myometrium and both in the proliferative and in the secretory phases. CONCLUSION: The significant and consistent increase in GPER expression in adenomyosis compared with control subjects, regardless of whether it was in the proliferative or secretory phases and regardless of whether it was in the JZ or OM, suggests that GPER plays an important role in the pathogenesis of the adenomyosis.

MicroRNA-1291 promotes endometrial fibrosis by regulating the ArhGAP29-RhoA/ROCK1 signaling pathway in a murine model.

Intrauterine adhesions (IUAs) are caused by endometrial damage and are associated with a poor pregnancy prognosis including infertility, oligomenorrhea and recurrent pregnancy loss. Understanding the pathogenesis of IUAs may help prevent and treat this condition more effectively. The aim of the current study was to investigate the function of microRNA­1291 (miR­1291) during the development of IUAs following endometrial damage and elucidate the potential molecular mechanisms involved. The expression of Rho GTPase activating protein 29 (ArhGAP29), a putative target mRNA of miR­1291, was determined by immunohistochemical staining of human endometrial tissue from patients with IUAs and compared with normal endometrial tissues. ArhGAP29 expression was significantly decreased in endometrial tissues with IUAs compared with normal endometrium. Additionally, a murine IUAs model was develo-ped and reverse transcription­quantitative polymerase chain reaction (RT­qPCR) demonstrated that miR­1291 levels were significantly increased in the uterine tissue and plasma of the IUAs group compared with the normal mice. Furthermore, an miR­1291 antagomir was injected into the uterine cavity of experimental IUAs mice to block miR­1291. Hematoxylin and eosin and Masson's stain revealed that blocking miR­1291 significantly ameliorated endometrial fibrosis. Furthermore, levels of epithelial mesenchymal transition (EMT)­associated proteins, and ArhGAP29­RhoA/Rho­associated coiled coil containing protein kinase 1 (ROCK1) were measured in uterine tissue by western blot, RT­qPCR analysis and immunofluorescence staining. Levels of the mesenchymal marker proteins, vimentin and N­cadherin, were increased in the IUAs group mice, accompanied by a relative decrease in the epithelial marker proteins, cytokeratin and E­cadherin compared with normal murine endometrium. miR­1291 inhibition decreased RhoA/ROCK1 expression in the EMT pathway, but increased ArhGAP29 expression. Taken together, the findings indicate that miR­1291 acts upstream of ArhGAP29 to negatively regulate the RhoA/ROCK1 EMT pathway, ultimately leading to endometrial fibrosis. These studies may provide new potential therapeutic options and pave the way to use circulating miR­1291 as a clinical biomarker of endometrial fibrosis.

Astragalosideâ £ against cardiac fibrosis by inhibiting TRPM7 channel.

BACKGROUND: Astragaloside Ⅳ (ASG-Ⅳ, (Fig. 1) is the most active component of Chinese sp. Astragalus membranaceus Bunge (Fabaceae) that has showed antioxidant, antiapoptotic and antiviral activities among others. It is reported to play an important role in cardiac fibrosis (CF), but the mechanism remains unclear. PURPOSE: To investigate the mechanism of ASG-Ⅳ on inhibiting myocardial fibrosis induced by hypoxia. STUDY DESIGN: We studied the relationship between anti-fibrotic effect of ASG-Ⅳ and transient receptor potential cation channel, subfamily M, member 7 (TRPM7) by in vivo and in vitro experiments. METHODS: In vivo, CF was induced by subcutaneous isoproterenol (ISO) for 10 days. Rat hearts were resected for histological experiment and reverse transcription real-time quantitative poly merase chain reaction (RT-qPCR). In vitro, molecular and cellular biology technologies were used to confirm the anti-fibrosis effect underlying mechanism of ASG-Ⅳ. RESULTS: Histological findings and the collagen volume fraction showed that ASG-Ⅳ decreased fibrosis in heart tissues. Hypoxia could stimulate the proliferation and differentiation of cardiac fibroblast which indicated that the degree of fibrosis was increased significantly. Anoxic treatment could also obviously up-regulate the expression of TRPM7 protein and current. ASG-Ⅳ groups showed the opposite results. Knock-down TRPM7 experiment further confirmed the role of TRPM7 channel in hypoxia-induced cardiac fibrosis. CONCLUSION: Our results suggest that the inhibition of hypoxia-induced CF in vivo and in vitro by ASG-IV is associated with reduction of the expression of TRPM7. The moderate inhibition of the TRPM7 channel may be a new strategy for treating cardiac fibrosis.

Human amniotic mesenchymal stromal cell transplantation improves endometrial regeneration in rodent models of intrauterine adhesions.

BACKGROUND AIMS: Intrauterine adhesion (IUA) is a common uterine cavity disease characterized by the unsatisfactory regeneration of damaged endometria. Recently, stem cell transplantation has been proposed to promote the recovery process. Here we investigated whether human amniotic mesenchymal stromal cells (hAMSCs), a valuable resource for transplantation therapy, could improve endometrial regeneration in rodent IUA models. METHODS: Forty female Sprague-Dawley rats were randomly assigned to five groups: normal, sham-operated, mechanical injury, hAMSC transplantation, and negative control group. One week after intervention and transplantation, histological analyses were performed, and immunofluorescent and immunohistochemical expression of cell-specific markers and messenger RNA expression of cytokines were measured. RESULTS: Thicker endometria, increased gland numbers and fewer fibrotic areas were found in the hAMSC transplantation group compared with the mechanical injury group. Engraftment of hAMSCs was detected by the presence of anti-human nuclear antigen-positive cells in the endometrial glands of the transplantation uteri. Transplantation of hAMSCs significantly decreased messenger RNA levels of pro-inflammatory cytokines (tumor necrosis factor-α and interleukin-1ß), and increased those of anti-inflammatory cytokines (basic fibroblast growth factor, and interleukin-6) compared with the injured uterine horns. Immunohistochemical expression of endometrial epithelial cells was revealed in specimens after hAMSC transplantation, whereas it was absent in the mechanically injured uteri. CONCLUSIONS: hAMSC transplantation promotes endometrial regeneration after injury in IUA rat models, possibly due to immunomodulatory properties. These cells provide a more easily accessible source of stem cells for future research into the impact of cell transplantation on damaged endometria.

Efficacy of freeze-dried amnion graft following hysteroscopic adhesiolysis of severe intrauterine adhesions.

OBJECTIVE: To evaluate the efficacy of freeze-dried amnion graft for prevention of intrauterine adhesion (IUA) reformation after hysteroscopic adhesiolysis. METHODS: A prospective randomized controlled trial was conducted among 88 women with severe IUAs who underwent hysteroscopic adhesiolysis at Beijing Obstetrics and Gynecology Hospital between July 15, 2015, and July 1, 2016. All participants had a balloon inserted into the uterine cavity for 1 week. Sterilized freeze-dried amnion graft covered the balloon portion of the Foley catheter among patients allocated to the amnion group (n=44), whereas patients in the control group (n=44) did not receive the graft. Follow-up hysteroscopy was performed 3 months after surgery. Preoperative and postoperative IUA scores, menstruation scores, and pregnancy rates were assessed. RESULTS: Both groups exhibited reductions in IUA scores and improvements in menstruation scores following treatment (P<0.001 for each measure). Compared with the control group, the amnion group had a lower IUA score (P=0.032) and a higher menstruation score (P<0.001) at follow-up. By contrast, the rates of IUA reformation and pregnancy were not significantly different between the two groups. CONCLUSION: Use of freeze-dried amnion graft was effective in reducing IUA reformation and improving menstruation (according to pictorial blood-loss assessment chart) following hysteroscopic adhesiolysis of severe IUAs. ClinicalTrials.gov: (NCT02496052).

Therapeutic effect of astragaloside-IV on bradycardia is involved in up-regulating klotho expression.

AIMS: In order to determine whether klotho is involved in the therapeutic effects of Astragaloside-IV on bradycardia, we evaluated the effect of ASG-IV on klotho and the effect of klotho on HCN4 and If. MAIN METHODS: Administrating isoproterenol (5 mg/kg) for 15 days to establish a rat bradycardia model randomized SD rats into control, model (ISO) and ASG-IV (5 mg/kg/day) groups to explore the effect of ASG-IV on klotho. Rats were sacrificed on day 15 after heart rate and heart function were measured; SAN tissues were collected to measure the expression of klotho and HCN4. In vitro, neonatal rat myocardial cells were incubated with LPS for 24 h to inhibit the expression of HCN4 and incubated with LPS+ klotho to explore the effect of klotho on HCN4 expression. We also adopted full-patch-clamp technique to explore the effect of klotho on If. KEY FINDINGS: Heart rate in model group was significantly decreased (356.6±19.7 vs. 428.9±19.9 in control group, P<0.01) and ASG-IV can increase heart rate (401.4±12.0 vs. 356.6±19.7 in model group, P<0.01). The expression of klotho was also up-regulated (P<0.05). In vitro, after incubation with LPS for 24h, HCN4 expression was significantly decreased in neonatal rat myocardial cells (0.6±0.07 vs. 1.0, P<0.01) and If was significantly declined. Exogenous klotho showed protective effect on HCN4 expression (1.58±0.16 in ASG-IV group vs. 0.6±0.07 in LPS group, P<0.05) and If. SIGNIFICANCE: Klotho is involved in the treatment mechanism of ASG-IV.

[The effects of psychological nursing on anxiety of patients in the procedure of impacted teeth extraction].

PURPOSE: To investigate the effects of psychological nursing on anxiety of patients during extraction of impacted teeth. METHODS: Seventy patients who required impacted tooth extraction were randomly divided into intervention group (n=35) and control group (n=35). In the intervention group, psychological nursing was performed by special nurses before, during and after the surgical procedure; In the control group, patients were informed the general knowledge of the routine treatment and care. Anxiety was evaluate with anxiety scale at the end of surgical procedure. The data was analyzed with SPSS 13.0 software package for X2 test. RESULTS: The number of patients with anxiety in the intervention group was significantly reduced compared with the control. The difference was statistically significant (P<0.05). CONCLUSIONS: Psychological nursing assists to relieve anxiety of patients during impacted teeth removal.

Antiarrhythmic ionic mechanism of Guanfu base A--Selective inhibition of late sodium current in isolated ventricular myocytes from guinea pigs.

The present study was designed to determine the effects of Guanfu base A (GFA) on the late sodium current (INa.L), transient sodium current (INa.T), HERG current (IHERG), and Kv1.5 current (IKv1.5). The values of INa.L, INa.T, IHERG and IKv1.5 were recorded using the whole-cell patch clamp technique. Compared with other channels, GFA showed selective blocking activity in late sodium channel. It inhibited INa.L in a concentration-dependent manner with an IC50 of (1.57 ± 0.14) µmol · L(-1), which was significantly lower than its IC50 values of (21.17 ± 4.51) µmol · L(-1) for the INa.T. The inhibitory effect of GFA on INa,L was not affected by 200 µmol · L(-1) H2O2. It inhibited IHERG with an IC50 of (273 ± 34) µmol · L(-1) and has slight blocking effect on IKv1.5, decreasing IKv1.5 by only 20.6% at 200 µmol · L(-1). In summary, GFA inhibited INa.L selectively and remained similar inhibition in presence of reactive oxygen species. These findings may suggest a novel molecular mechanism for the potential clinical application of GFA in the treatment of cardiovascular disorders.

CPUY11018, an azimilide derivative, ameliorates isoproterenol-induced cardiac insufficiency through relieving dysfunctional mitochondria and endoplasmic reticulum.

OBJECTIVES: Deterioration of cardiac performance under stress may be partly mediated by dysfunctional mitochondria and endoplasmic reticulum (ER) that is likely related to an activation of NADPH oxidase (NOX) and an increase in pro-inflammatory factors. We investigated if a new compound CPUY11018 (CPUY) derived from Azimilide could ameliorate the stress impaired cardiac performance. METHODS: Forty-eight male Sprague Dawley rats were randomly divided into six groups and were injected with isoproterenol (ISO, 1 ml/kg, s.c.) for 10 days. Cardiac myocytes and fibroblasts from neonate rats were incubated with ISO. CPUY was employed and compared with apocynin (APO) - an inhibitor of NOX. KEY FINDINGS: In ISO-treated group, the compromised haemodynamics and cardiac remodelling were significant with dysfunctional mitochondria indicated by decreased MnSOD and mitochondrial membrane potential, and an enhanced reactive oxygen species genesis. Downregulation of FKBP12.6, CASQ2 and SERCA2a was also remarkable in vivo and in vitro implying an abnormal ER. Upregulated Nox4, p22(phox) and p47(phox) were significant, associated with upregulation of Src, IκBß and NFκB, and downregulation of pAMPK/AMPK and Cx40 in vivo and in vitro. These abnormalities were relieved by CPUY and APO. CONCLUSIONS: CPUY is potential in managing cardiac insufficiency through normalizing mitochondria and ER in the affected heart.

The antitumor activity of tumor-homing peptide-modified thermosensitive liposomes containing doxorubicin on MCF-7/ADR: in vitro and in vivo.

Clotted plasma proteins are present on the walls of tumor vessels and in tumor stroma. Tumor-homing peptide Cys-Arg-Glu-Lys-Ala (CREKA) could recognize the clotted plasma proteins in tumor vessels. Thermosensitive liposomes could immediately release the encapsulated drug in the vasculature of the heated tumor. In this study, we designed a novel form of targeted thermosensitive liposomes, CREKA-modified lysolipid-containing thermosensitive liposomes (LTSLs), containing doxorubicin (DOX) (DOX-LTSL-CREKA), to investigate the hypothesis that DOX-LTSL-CREKA might target the clotted plasma proteins in tumor vessels as well as tumor stroma and then exhibit burst release of the encapsulated DOX at the heated tumor site. We also hypothesized that the high local drug concentration produced by these thermosensitive liposomes after local hyperthermia treatment will be useful for treatment of multidrug resistance. The multidrug-resistant human breast adenocarcinoma (MCF-7/ADR) cell line was chosen as a tumor cell model, and the targeting and immediate release characteristics of DOX-LTSL-CREKA were investigated in vitro and in vivo. Furthermore, the antitumor activity of DOX-LTSL-CREKA was evaluated in MCF-7/ADR tumor-bearing nude mice in vivo. The targeting effect of the CREKA-modified thermosensitive liposomes on the clotted plasma proteins was confirmed in our in vivo imaging and immunohistochemistry experiments. The burst release of this delivery system was observed in our in vitro temperature-triggered DOX release and flow cytometry analysis and also by confocal microscopy experiments. The antitumor activity of the DOX-LTSL-CREKA was confirmed in tumor-bearing nude mice in vivo. Our findings suggest that the combination of targeting the clotted plasma proteins in the tumor vessel wall as well as tumor stroma by using CREKA peptide and temperature-triggered drug release from liposomes by using thermosensitive liposomes offers an attractive strategy for chemotherapeutic drug delivery to tumors.

Antitumor effect of iRGD-modified liposomes containing conjugated linoleic acid-paclitaxel (CLA-PTX) on B16-F10 melanoma.

In the present study, we prepared a novel delivery system of iRGD (CRGDK/RGPD/EC)-modified sterically stabilized liposomes (SSLs) containing conjugated linoleic acid-paclitaxel (CLA-PTX). The anti-tumor effect of iRGD-SSL-CLA-PTX was investigated on B16-F10 melanoma in vitro and in vivo. The in vitro targeting effect of iRGD-modified SSLs was investigated in a real-time confocal microscopic analysis experiment. An endocytosis-inhibition assay was used to evaluate the endocytosis pathways of the iRGD-modified SSLs. In addition, the in vitro cellular uptake and in vitro cytotoxicity of iRGD-SSL-CLA-PTX were evaluated in B16-F10 melanoma cells. In vivo biodistribution and in vivo antitumor effects of iRGD-SSL-CLA-PTX were investigated in B16-F10 tumor-bearing mice. The induction of apoptosis by iRGD-SSL-CLA-PTX was evaluated in tumor-tissue sections. Real-time confocal microscopic analysis results indicated that the iRGD-modified SSLs internalized into B16-F10 cells faster than SSLs. The identified endocytosis pathway of iRGD-modified SSLs indicated that energy- and lipid raft-mediated endocytosis played a key role in the liposomes' cellular uptake. The results of the cellular uptake experiment indicated that the increased cellular uptake of CLA-PTX in the iRGD-SSL-CLA-PTX-treated group was 1.9-, 2.4-, or 2.1-fold compared with that in the CLA-PTX group after a 2-, 4-, or 6-hour incubation, respectively. In the biodistribution test, the CLA-PTX level in tumor tissues from iRGD-SSL-CLA-PTX-treated mice at 1 hour (1.84±0.17 µg/g) and 4 hours (1.17±0.28 µg/g) was 2.3- and 2.0-fold higher than that of CLA-PTX solution at 1 hour (0.79±0.06 µg/g) and 4 hours (0.58±0.04 µg/g). The value of the area under the curve for the first 24 hours in the tumors of iRGD-SSL-CLA-PTX-treated mice was significantly higher than that in the SSL-CLA-PTX and CLA-PTX solution-treated groups (P<0.01). The in vivo antitumor results indicated that iRGD-SSL-CLA-PTX significantly inhibited the growth of B16-F10 tumors compared with the SSL-CLA-PTX or CLA-PTX solution-treatment groups (P<0.01). The results of tumor-cell apoptosis showed that tumors from the iRGD-SSL-CLA-PTX-treated group exhibited more advanced cell apoptosis compared with the control, CLA-PTX solution-, and SSL-CLA-PTX-treated groups. In conclusion, the antitumor effect of iRGD-SSL-CLA-PTX was confirmed on B16-F10 melanoma in vitro and in vivo.

New diterpenoid alkaloids from Aconitum coreanum and their anti-arrhythmic effects on cardiac sodium current.

Two new diterpenoid alkaloids, Guan-Fu base J (GFJ, 1) and Guan-Fu base N (GFN, 2) along with nineteen known alkaloids (3-21) were isolated from the roots of Aconitum coreanum (Lèvl.) Rapaics, which is the raw material of a new approval anti-arrhythmia drug "Acehytisine Hydrochloride". The structures of isolated compounds were established by means of 1D, 2D NMR spectroscopic and chemical methods. All isolates obtained in the present study were evaluated for their inhibitory effects on blocking the ventricular specific sodium current using a whole-cell patch voltage-clamp technique. Among these 21 compounds, Guan-Fu base S (GFS, 3) showed the strongest inhibitory effect with an IC50 value of 3.48 µM, and only hetisine-type C20 diterpenoid alkaloids showed promising IC50 values for further development.

Synthesis and ß-adrenergic blocking activity of oxime ether hybrids derived from a natural isochroman-4-one.

AIM: In a search for new cardiovascular drug candidates, a series of novel oxime ethers derived from a natural isochroman-4-one were synthesized. METHOD: Compounds 3 and 6, derived from the natural antihypertensive compound 7, 8-dihydroxy-3-methyl-isochroman-4-one (XJP), were designed and synthesized. Subsequently, a series of novel isochroman-4-one oxime ether hybrids were prepared by hybridizing various N-substituted isopropanolamine functionalities to isochroman-4-one oxime. Furthermore, ß1-adrenergic blocking activities of the synthesized compounds were assayed using the isolated rat left atria. RESULTS: Twenty target compounds were obtained, and the preliminary structure-activity relationships were deduced. The most promising compound Ic exhibited ß1-adrenoceptor blocking activity (inhibition: 52.2%) at 10(-7) mol·L(-1), which was superior to that of propranolol (inhibition: 49.7%). CONCLUSION: The results suggested that natural product XJP/isopropanolamine moiety hybrids may provide a promising approach for the discovery of novel cardiovascular drug candidates.

Raisanberine protected pulmonary arterial rings and cardiac myocytes of rats against hypoxia injury by suppressing NADPH oxidase and calcium influx.

AIM: To investigate the protection of pulmonary arterial rings and cardiac myocytes of rats by raisanberine (RS), a derivative of berberine, against hypoxia injury and to elucidate the action mechanisms. METHODS: Adult SD rats were exposed to intermittent hypoxia for 17 d or 28 d. The pulmonary arterial rings were isolated and vascular activity was measured using a transducer and computer-aided system. The difference in the tension produced by phenylephrine in the presence and absence of L-nitroarginine (10 µmol/L) was referred to as the NO bioavailability; the maximum release of NO was assessed by the ratio of the maximal dilatation caused by ACh to those caused by sodium nitroprusside. After the lungs were fixed, the internal and the external diameters of the pulmonary arterioles were measured using a graphic analysis system. Cultured cardiac myocytes from neonatal rats were exposed to H(2)O(2) (10 µmol/L) to mimic hypoxia injury. ROS generation and [Ca(2+)](i) level in the myocytes were measured using DHE and Fluo-3 fluorescence, respectively. RESULTS: Oral administration of RS (80 mg/kg), the NADPH oxidase inhibitor apocynin (APO, 80 mg/kg) or Ca(2+) channel blocker nifedipine (Nif, 10 mg/kg,) significantly alleviated the abnormal increase in the vasoconstriction force and endothelium-related vasodilatation induced by the intermittent hypoxia. The intermittent hypoxia markedly decreased the NO bioavailability and maximal NO release from pulmonary arterial rings, which were reversed by APO or RS administration. However, RS administration did not affect the NO bioavailability and maximal NO release from pulmonary arterial rings of normal rats. RS, Nif or APO administration significantly attenuated the pulmonary arteriole remodeling. Treatment of cultured cardiac myocytes with RS (10 µmol/L) suppressed the ROS generation and [Ca(2+)](i) increase induced by H(2)O(2), which were comparable to those caused by APO (10 µmol/L) or Nif (0.1 µmol/L). CONCLUSION: Raisanberine relieved hypoxic/oxidant insults to the pulmonary artery and cardiac myocytes of rats by suppressing activated NADPH oxidase and increased calcium influx.

Comparison of sildenafil with strontium fructose diphosphate in improving erectile dysfunction against upregulated cavernosal NADPH oxidase, protein kinase Cε, and endothelin system in diabetic rats.

OBJECTIVES: Phosphodiesterase type 5 inhibitors are potent in relieving erectile dysfunction (ED), however, they are less satisfactory in diabetic patients, probably due to the pro-inflammatory biomarkers caused by diabetes. Therefore, it was interesting to compare the effects of sildenafil with strontium fructose 1,6-diphosphate (FDP-Sr) on cavernosal vascular activity and expressions of pro-inflammatory biomarkers in diabetic rats. METHODS: Male Sprague-Dawley rats were injected with streptozocin (60 mg/kg, i.p.) to develop diabetes. The animals were diabetic for eight weeks with sildenafil (12 mg/kg per day) or FDP-Sr (200 mg/kg per day) being administered for the last four of those eight weeks. KEY FINDINGS: Sildenafil was more effective in relieving reduced vascular dilatation (relevant to ED), but less in attenuating over-expressions of NADPH oxidase p22, p47 and p67 subunits, and ET(A/B) R (endothelin receptor type A and type B) in the diabetic cavernosum. In contrast, FDP-Sr was less effective in improving ED, but more effective in normalizing the abnormal NADPH oxidase and ET(A/B) R. CONCLUSIONS: The activated NADPH oxidase and upregulated ET(A) R and ET(B) R due to diabetic lesions played a minor or moderate role in ED. By offering extra ATP, FPD-Sr suppressed these abnormalities, however, sildenafil did not. A combined therapy of sildenafil with FDP-Sr may be more effective in relieving ED in diabetic patients through normalizing pro-inflammatory cytokines and improving the nitric oxide/cGMP pathway in the cavernosum.

AQP4 knockout mice manifest abnormal expressions of calcium handling proteins possibly due to exacerbating pro-inflammatory factors in the heart.

We tested the hypothesis that aquaporin-4 (AQP4) knockout (KO) mice might exhibit abnormal Ca(2+) modulating proteins resulting from the exacerbation of pro-inflammatory factors in the heart. Downregulation of FKBP12.6, SERCA2a, and CASQ2 and calcium leak in diastole have been recognized as endpoints for assessing cardiac failure and arrhythmias. The AQP4 KO mice and wild-type (WT) mice were randomly divided into 3 groups, such as control, isoproterenol (ISO, ß-receptor agonist) injected (1 mg/kg, sc, 5 d), and treated with aminoguanidine (AMG, 100 mg/kg, po, a selective inhibitor of the iNOS) during the last 3d. RT-PCR, western blot and calcium transient measurements were conducted. The results demonstrated that the cardiac weight index was increased in AQP4 KO mice and further increased following treatment with ISO. The expression levels of FKBP12.6, SERCA2a, and CASQ2 were downregulated and diastolic calcium concentrations were elevated in the AQP4 KO mice, indicative of a calcium leak. In the myocardium, expressions of pro-inflammatory biomarkers, including ET(A), pPKCɛ, NADPH oxidase p67(phox) were upregulated and associated with downregulation of Cx43. The aforementioned changes were exacerbated in response to ISO medication and were attenuated by AMG; however, its treatment effectiveness was less in the AQP4 KO mice. We concluded AQP4 KO caused abnormalities of calcium modulating proteins leading to an exacerbation of risk for cardiac arrhythmias and failure. These changes are likely due to an increase in pro-inflammatory factors which are exacerbated by stress. Therefore, AQP4 KO mice are prone to cardiac failure and arrhythmias through exacerbating pro-inflammatory factors in the myocardium.

[The research practice of anti-arrhythmic agents targeting on potassium ion channel].

Due to the complicated pathogenesis of cardiac arrhythmia, the safe and effective therapeutic strategies for cardiac arrhythmia remain an urgent medical problems in the recent years. In this paper, we introduced the research practice of anti-arrhythmic agents targeting on potassium ion channel. The research progress of anti-arrhythmic agents in up-to-date literatures were also reviewed and prospected.

Metabolism of protocatechuic acid influences fatty acid oxidation in rat heart: new anti-angina mechanism implication.

Protocatechuic acid (PA), a structurally typical phenolic acid in danshen, shows anti-angina efficacy. But until now, besides scavenging of oxygen free radicals, the understanding of its anti-angina mechanism has been limited. In our study, based on a novel metabolic route of PA identified in rat heart and its influence on fatty acid oxidation (FAO), we proposed a new mechanism for its anti-angina. In detail, three metabolites, catechol methylated metabolite, acyl-coenzyme (CoA) thioester and glycine conjugation, were identified in rat heart. A novel metabolic pathway was confirmed based on several metabolic systems incubated with heart mitochondria, cytosol, microsomes and homogenate. Results indicated that PA was firstly methylated in microsomes and cytosol, which was regarded as the prerequisite step for further metabolism and could be inhibited by tolcapone, and then the resulting methylated metabolite (vanillic acid) diffused into mitochondria where it was converted into acyl-CoA thioester, in similar with FAO. In addition, part of the acyl-CoA thioester was transformed into glycine conjugation, a step also localized within mitochondria. Furthermore, based on isolated rat heart perfusion, it was found that PA markedly decreased FAO, which was shown by higher residual fatty acid level in perfusate (p<0.05) and lower acy-CoA/CoA ratio in heart (p<0.05). The FAO inhibiting effect of PA could be largely reversed by its methylation inhibitor tolcapone, indicating the effect was closely related with the identified metabolic pathway of PA in heart. The decrease of FAO may switch heart energy substrate preference from fatty acid to glucose, which is beneficial for ischemia heart.