The inhibition of ß-catenin activity by luteolin isolated from Paulownia flowers leads to growth arrest and apoptosis in cholangiocarcinoma.

To develop an inhibitor targeting the Wnt/ß-catenin signaling pathway, flavonoid monomer that can interact with ß-catenin was isolated from Paulownia flowers. Luteolin may form stable hydrogen bonds with ß-catenin by molecular docking. Fluorescence quenching analysis determined the physical interaction between luteolin and ß-catenin. The binding of luteolin to ß-catenin caused a loss of α-helical structure and induced a conformational change through circular dichroism spectroscopy. Luteolin inhibits the activity of the Wnt signaling, causing cholangiocarcinoma (CCA) cell cycle arrest in the G2/M phase, leading to cell apoptosis and inhibition of cell migration. In addition, transcriptome and proteomics analysis showed that the differentially expressed proteins were significantly enriched in the Wnt/ß-catenin pathway. ß-catenin protein in the nucleus was significantly decreased, while C-Myc and cyclin D1 in the CCA cells were significantly decreased after luteolin treatment. Additionally, activation of the Wnt/ß-catenin signaling reversed the inhibitory effect of luteolin on the migration of CCA cells. Therefore, luteolin can directly interact with ß-catenin and act as an inhibitor of ß-catenin, inhibiting proliferation and reducing the migration ability of CCA cells by inhibiting the Wnt/ß-catenin pathway. This study provides a scientific basis for the development of Wnt/ß-catenin pathway inhibitors and the prevention and treatment of CCA.

The m6A mRNA demethylase FTO regulates GnRH secretion in Mn-induced precocious puberty.

The GABAA receptor (GABAAR) plays important roles in the regulation of Mn-induced GnRH secretion in immature female rats. However, the underlying molecular mechanisms remain unknown. Here, we assessed whether FTO and its substrate m6A are correlated with GABAAR expression in GnRH neurons after treatment with Mn in vitro and in vivo. Our study indicated that Mn treatment increased the expression of GnRH mRNA and decreased the levels of GABAAR protein but had no effect on GABAAR mRNA. Moreover, Mn upregulated the levels of FTO and inhibited global cellular m6A levels and GABAAα2 mRNA m6A levels. Knockdown of FTO increased the expression of GABAAR protein and GABAAα2 mRNA m6A levels. Data from rat models further demonstrate that inhibition of FTO suppressed GABAAR protein expression in the hypothalamus, causing delayed puberty onset. Collectively, our findings suggest that FTO-dependent m6A demethylation plays a critical role in regulating GABAAR mRNA processing in GnRH neurons.

Oxidative Stress and Trace Elements in Pulmonary Tuberculosis Patients During 6 Months Anti-tuberculosis Treatment.

Pulmonary tuberculosis (TB) is a well-known cause of imbalance in oxidative stress (OS) status and trace element levels. However, little information is available for targeting the correlation between OS and trace elements in pulmonary TB patients. The aim of our study was to analyze the OS status and its correlation with trace elements in patients initially and during 6 months anti-TB treatment. Eighty-six newly diagnosed pulmonary TB patients were consecutively recruited, and 112 age- and sex-matched healthy controls participated in the study. Serum markers of OS and trace elements levels were tested and analyzed in all subjects during 6 months anti-TB treatment. Compared with healthy controls, significantly increased level of malondialdehyde (MDA), decreased glutathione (GSH) level, superoxide dismutase (SOD), and catalase (CAT) activities were found in TB patients. The activities of SOD and CAT and GSH level recovered till normal range at treatment final. Zinc (Zn), selenium (Se), and copper (Cu) concentrations were significantly lower in TB patients in comparison with healthy controls, whereas Zn, Cu, and Se concentrations rise during 6 months anti-TB treatment. Zn was positively correlated with Cu, Se, and GSH, while MDA was negatively correlated with Zn, Se, SOD, and CAT, and SOD was positively correlated with Cu, Zn, and CAT. Our findings indicate that anti-TB treatment could reduce the status of OS and increase the levels of trace elements. The routine assessment of OS markers and element traces may guarantee improved monitoring the anti-TB treatment.

Manganese exposure caused reproductive toxicity of male mice involving activation of GnRH secretion in the hypothalamus by prostaglandin E2 receptors EP1 and EP2.

Exposure to manganese (Mn) can cause male reproductive damage and lead to abnormal secretion of sex hormones. Gonadotropin-releasing hormone (GnRH) plays an important role in the neuromodulation of vertebrate reproduction. Astrocytes can indirectly regulate the secretion of GnRH by binding paracrine prostaglandin E2 (PGE2) specifically to the EP1 and EP2 receptors on GnRH neurons. Prior studies assessed the abnormal secretion of GnRH caused by Mn exposure, but the specific mechanism has not been reported in detail. This study investigated the effects of Mn exposure on the reproductive system of male mice to clarify the role of PGE2 in the abnormal secretion of GnRH in the hypothalamus caused by exposure to Mn. Our data demonstrate that antagonizing the EP1 and EP2 receptors of PGE2 can restore abnormal levels of GnRH caused by Mn exposure. Mn exposure causes reduced sperm count and sperm shape deformities. These findings suggest that EP1 and EP2, the receptors of PGE2, may be the key to abnormal GnRH secretion caused by Mn exposure. Antagonizing the PGE2 receptors may reduce reproductive damage caused by Mn exposure.

The effect of manganese exposure on GnRH secretion via Nrf2/mGluR5/COX-2/PGE2/signaling pathway.

There are limited studies focused on the precise mechanism of gonadotropin-releasing hormone (GnRH) secretion dysfunction after overexposure to manganese (Mn). The objective of the present study was to explore the mechanism of Mn disruption of GnRH synthesis via nuclear factor erythroid-2-related factor-2 (Nrf2)/metabotropic glutamate receptor-5 (mGluR5)/cyclooxygenase-2 (COX-2)/prostaglandin E2 (PGE2) signaling pathway in vitro and in vivo. Primary astrocytes were cultured and treated with different doses of Mn, tert-butylhydroquinonet (tBHQ; Nrf2 agonists), 3-[(2-methyl-4-thaizolyl) ethynyl] pyridine (MTEP; mGluR5 inhibitor), and celecoxib (COX-2 inhibitor) to measure the levels of COX-2, mGluR5, Nrf2, and Nrf2 target genes. Mice were randomly divided into 11 groups, of which included the control group, 12.5-, 25-, and 50-mg/kg MnCl2 group, dimethyl sulfoxide (DMSO) group, tBHQ control group, tBHQ pretreatment group, MTEP control group, MTEP pretreatment group, celecoxib control group, and celecoxib pretreatment group. The injection was administered every day for 2 weeks. Then, levels of GnRH, PGE2, COX-2, mGluR5, Nrf2, Nrf2 target genes, and morphological changes in the hypothalamus of mice were measured. Mn reduced protein levels of Nrf2 and mRNA expression of Nrf2 target genes and increased mGluR5, COX-2, PGE2, and GnRH levels. Meanwhile, injury-related histomorphology changes in the hypothalamus of mice were significantly present. In conclusion, excessive exposure to Mn disrupts GnRH secretion through Nrf2/mGluR5/COX-2/PGE2 signaling pathway.

Hyperoside Suppresses Lipopolysaccharide-induced Inflammation and Apoptosis in Human Umbilical Vein Endothelial Cells.

Finding the novel drug from the effective components of traditional Chinese herbal medicine is a hotspot of the modern pharmacological research. Hyperoside (HYP) belongs to flavonoid glycosides, and it has various properties, such as anti-inflammation, anti-spasm, anti-diuretic, antitussive, lowering blood pressure, and lowering cholesterol effects as well as protective effects for the cardiac and cerebral blood vessels. The purpose of this study was to investigate the effects of HYP on inflammatory and apoptotic responses in vascular endothelial cells stimulated by lipopolysaccharide (LPS) and further to identify the possible mechanisms underlying these effects. In our study, human umbilical vein endothelial cells (HUVECs) were stimulated with 1 µg/mL LPS in the presence or absence of HYP (10, 20 and 50 µmol/L). Our results indicated that HYP alone exerted no cytotoxicity on HUVECs, while it had an up-regulatory effect on the viability of HUVECs induced by LPS in a dose-dependent manner; increased mRNA expression of IL-1ß, IL-6, TNFα and iNOS induced by LPS was attenuated after treatment with HYP both in a dose-and time-dependent manner; LPS-induced HUVECs apoptosis and cleaved-caspase 8, 9, 3 were all significantly reduced by HYP. Furthermore, the possible pathway involved in apoptosis and inflammation by HYP was detected, and the results showed that when treated with HYP, LPS-induced mitochondrial membrane instability was significantly inhibited through up-regulation of Bcl-2 and down-regulation of Bax. Furthermore, the expression of TLR4 and the phosphorylation of IκBα and p65 in LPS-treated cells were blocked by HYP. Our results suggested that HYP treatment prevented HUVECs from LPSinduced inflammation and apoptosis responses, which might be mediated by inhibiting TLR4/NFκB pathway.

Melatonin improves cardiac function in a mouse model of heart failure with preserved ejection fraction.

Melatonin has been shown to inhibit myocardial infarction-induced apoptosis, its function in heart failure with preserved ejection fraction (HFpEF) has not been investigated. This study aimed to investigate whether melatonin attenuates obesity-related HFpEF. Male mice were fed a high-fat diet (HFD) from weaning to 6 months of age to induce HFpEF. The mice were orally administered melatonin (50 mg/kg) by 3 weeks. Diastolic function was significantly improved by melatonin supplementation in mice fed an HFD. Melatonin attenuated obesity-induced myocardial oxidative stress and apoptosis and promoted the secretion of C1q/tumour necrosis factor-related protein 3 (CTRP3) by adipose tissue. And depletion of circulating CTRP3 largely abolished melatonin-mediated cardio-protection. Melatonin-mediated secretion of adipocyte-derived CTRP3 activated NF-E2-related factor 2 (Nrf2), which were largely abrogated by knocking down CTRP3 in adipocytes or Nrf2 in cardiomyocytes. Nrf2 activation was mediated by miR-200a, and a miR-200a antagomir offset the effects of melatonin-conditioned medium on Nrf2 expression. Our results indicate that melatonin can be used to treat and prevent obesity-related HFpEF.

Isolation and Purification of Condensed Tannin from the Leaves and Branches of Prunus cerasifera and Its Structure and Bioactivities.

Prunus cerasifera has a rich resource and a weak utilization rate and its biological functions have been investigated. We found that the contents of total phenol (TP) in leaves and branches of Prunus cerasifera were 117.8 ± 8.8 and 100.04 ± 0.9 mg/g, respectively; the contents of soluble condensed tannin (SCT) were 73.95 ± 0.9 and 78.65 ± 4.1 mg/g, respectively; the structure of SCT containing afzelechin/epiafzelechin, catechin/epicatechin, and atechin/epicatechin as the main units and the SCT from leaves and branches exhibited better anti-tyrosinase and antioxidant activities. This study could clarify Prunus cerasifera condensed tannin resource availability and lay a theoretical foundation for its development as a natural antioxidant and tyrosinase inhibitor.

Concentration­dependent effects of paeoniflorin on proliferation and apoptosis of vascular smooth muscle cells.

Vascular smooth muscle cells (VSMCs) are an important component of arterial walls, and their dysfunction may serve an important role in the development of cardiovascular diseases, including atherosclerosis and restenosis. Paeoniflorin (PF) is a principal component of the commonly used traditional Chinese medicine, peonies. To the best of our knowledge, the effects of PF on apoptosis and proliferation of VSMCs and its underlying molecular mechanisms have not been widely reported. Therefore, the present study was designed to investigated this phenomenon. VSMCs were treated with different concentrations of PF (25, 50 and 100 µg/ml) for 12, 24 or 48 h. The data demonstrated that PF treatment not only significantly decreased cell viability and DNA synthesis but also blocked G0/G1 cell cycle progression. This effect was associated with a decreased expression of cyclin D1, cyclin E, cyclin­dependent kinase (CDK)4 and CDK2 as well as an upregulation of p21. Notably, a significant concentration­dependent decrease in the phosphorylation of p65 and nuclear factor of κ light polypeptide gene enhancer in B­cells inhibitor­α (IκBα) was observed. In addition, it was demonstrated that PF promoted the apoptosis of VSMCs, which was associated with the increased expression of caspases. In conclusion, PF inhibited the proliferation of VSMCs by downregulating proteins associated with the nuclear factor­κB signaling pathway. Furthermore, it promoted the apoptosis of VSMCs by upregulating the expression of caspases. These results may be useful in improving the understanding of the molecular mechanisms underlying the apoptotic and anti­proliferative effects of PF on VSMCs, and facilitate the development of novel treatments for cardiovascular diseases.

Sinomenine, a COX-2 inhibitor, induces cell cycle arrest and inhibits growth of human colon carcinoma cells in vitro and in vivo.

Certain non-steroidal anti-inflammatory drugs may possess anti-tumorigenic effects in certain cancer cell types. Sinomenine (SIN) is an alkaloid from Sinomenium acutum, a Chinese medicinal plant that inhibits inflammatory reactions and that has been used in the treatment of neuralgia and rheumatic diseases. In this study, we investigated the anticancer effects of SIN against colorectal cancer in vitro and in vivo, as well as the underlying mechanisms. The effects of SIN on proliferation, cell cycle progression and cyclooxygenase (COX)-2 expression were examined in human colorectal cancer-derived SW1116 cells. The in vivo effects of SIN were examined in a model of SW1116 tumor xenograft growth in athymic nude mice. Changes in COX-2 expression induced by the biological effects of SIN were analyzed by western blot analysis. The effects of SIN treatment on G1 phase cell cycle regulators in xenografts were analyzed by immunohistochemistry. Our findings demonstrate that SIN inhibits the proliferation of SW1116 cells by promoting their accumulation in the G1 phase, with concomitant suppression of COX-2 expression. Time- and dose-dependent inhibition of tumor growth and reduced toxicity were observed in nude mice administered daily intraperitoneal injections of SIN at doses of 25, 50 and 100 mg/kg. SIN-treated tumors also exhibited reduced COX-2 expression, a marked increase in Cip1/p21 protein levels and a decrease in the levels of cyclin D1 and cyclin E. SIN may be an effective chemopreventive agent against colorectal cancer. The growth inhibitory properties of SIN against colorectal cancer may be mediated via a COX-2 inhibitory effect and cell cycle arrest in the G1 phase.

Efficacy and safety of the Chinese herbal medicine shuganjieyu with and without adjunctive repetitive transcranial magnetic stimulation (rTMS) for geriatric depression: a randomized controlled trial.

BACKGROUND: Pharmacological treatment of geriatric depression is often ineffective because patients cannot tolerate adequate doses of antidepressant medications. AIM: Examine the efficacy and safety of shuganjieyu - the first Chinese herbal medicine approved for the treatment of depression by China's drug regulatory agency -- with and without adjunctive treatment with repetitive transcranial magnetic stimulation (rTMS) in the treatment of geriatric depression. METHODS: Sixty-five inpatients 60 or older who met ICD-10 criteria for depression were randomly assigned to an experimental group (shuganjieyu + rTMS) (n=36) or a control group (shuganjieyu + sham rTMS)(n=29). All participants received 4 capsules of shuganjieyu daily for 6 weeks. rTMS (or sham rTMS) was administered 20 minutes daily, five days a week for 4 weeks. Blinded raters used the Hamilton Rating Scale for Depression (HAMD-17) and the Treatment Emergent Symptom Scale to assess clinical efficacy and safety at baseline and 1, 2, 4, and 6 weeks after starting treatment. Over the six-week trial, there was only one dropout from the experimental group and two dropouts from the control group. RESULTS: None of the patients had serious side effects, but 40% in the experimental group and 50% in the control group experienced minor side effects that all resolved spontaneously. Both groups showed substantial stepwise improvement in depressive symptoms over the 6 weeks. Repeated measures ANOVA found no differences between the two groups. After 6 weeks, 97% of the experimental group had experienced a 25% or greater drop in the level of depression, but only 20% had experience a 50% or greater drop in the level of depression; the corresponding values in the control group were 96% and 19%. There were some minor, non-significant differences in the onset of the treatment effect between the different types of depressive symptoms, but by the second week of treatment all five HAMD-17 subscale scores had improved significantly in both groups. CONCLUSION: The Chinese herbal medicine shuganjieyu is effective and safe in the treatment of geriatric depression, but only a minority of patients have greater than 50% improvement in their depressive symptoms after 6 weeks of treatment. Adjunctive use of rTMS with shuganjieyu does not improve the overall outcome and does not significantly speed up the onset of action of shuganjieyu.

Excitotoxicity and oxidative damages induced by methylmercury in rat cerebral cortex and the protective effects of tea polyphenols.

Methylmercury (MeHg) is a highly neurotoxic environmental pollutant that has a high appetency to the central nervous system. The underlying mechanisms of MeHg-induced neurotoxicity have not been elucidated clearly until now. Therefore, to explore the mechanisms contribute to MeHg-induced neurotoxicity, rats were exposed to different dosage of methylmercury chloride (CH3 ClHg) (0, 4, and 12 µmol kg(-1)) for 4 weeks to evaluate the neurotoxic effects of MeHg. In addition, considering the antioxidative properties of tea polyphenols (TP), 1 mmol kg(-1) TP was pretreated to observe the possible protective effects on MeHg-induced neurotoxicity. Then Hg, glutamate (Glu) and glutamine (Gln) levels, glutamine synthetase (GS), phosphate-activated glutaminase (PAG), Na(+)-K(+)-ATPase, and Ca(2+)-ATPase activities, intracellular Ca(2+) level were examined, glutathione (GSH), malondialdehyde (MDA), protein sulfhydryl, carbonyl, 8-hydroxy-2-deoxyguanosine (8-OHdG), and reactive oxygen species (ROS) levels, N-methyl-D-aspartate receptors (NMDARs) mRNA and protein expressions, apoptosis level and morphological changes in the cerebral cortex were also investigated. Study results showed that compared with those in control, exposure to CH3 ClHg resulted in excitotoxicity in a concentration-dependent manner, which was shown by the Glu-Gln cycle disruption and intracellular Ca(2+) homeostasis disturbance. On the other hand, CH3 ClHg exposure resulted in oxidative damages of brain, which were supported by the significant changes on GSH, MDA, sulfhydryl, carbonyl, 8-OHdG, and ROS levels. Moreover, apoptosis rate increased obviously and many morphological changes were found after CH3 ClHg exposure. Furthermore, this research indicated that TP pretreatment significantly mitigated the toxic effects of MeHg. In conclusion, findings from this study indicated that exposure to MeHg could induce excitotoxicity and oxidative damage in cerebral cortex while TP might antagonize the MeHg-induced neurotoxicity.

Effect of grape seed proanthocyanidin extracts on methylmercury-induced neurotoxicity in rats.

As a highly toxic environmental pollutant, methylmercury (MeHg) can cause neurotoxicity in animals and humans. Considering the antioxidant property of grape seed proanthocyanidin extracts (GSPE), this study was aimed to evaluate the effect of GSPE on MeHg-induced neurotoxicity in rats. Rats were exposed to MeHg by intraperitoneal injection (4, 12 µmol/kg, respectively) and GSPE was administered by gavage (250 mg/kg) 2 h later. After a 4-week treatment, phosphate-activated glutaminase, glutamine synthetase, glutathione peroxidase and superoxide dismutase activities, glutamate, glutamine, malondialdehyde and glutathione contents in cerebral cortex were measured. Reactive oxygen species (ROS) and apoptosis were also estimated in cells. The results showed that the MeHg-induced neurotoxicity was significantly attenuated. GSPE significantly decreased the production of ROS, counteracted oxidative damage and increased the antioxidants and antioxidant enzymes activities in rats prior to MeHg exposure. Moreover, the effects on the rate of apoptotic cells and the disturbance of glutamate homeostasis were correspondingly modulated. These observations highlighted the potential of GSPE in offering protection against MeHg-induced neurotoxicity.

The protective effects of tea polyphenols and schisandrin B on nephrotoxicity of mercury.

Mercury (Hg) is an occupational and environmental contaminant that is a well-recognized health hazard. To approach the concrete mechanisms of mercury nephrotoxicity and find out a new way to prevent it, the rats were subcutaneously injected with different dosages of mercuric chloride (HgCl(2))--0, 2.2, 4.4, and 8.8 µmol/kg. The levels of Hg, blood urea nitrogen (BUN), urine protein, glutathione (GSH), malondialdehyde (MDA) and activities of N-acetyl-beta-D-glucosaminidase (NAG), alkaline phosphatase (ALP), lactate dehydrogenase (LDH), superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px) were investigated, and the levels of reactive oxygen species (ROS) and apoptosis and the pathological changes were also observed. In addition, the effects of 1 mmol/kg tea polyphenols (TP) and 0.04 mmol/kg schisandrin B (Sch B) were studied at 8.8 µmol/kg HgCl(2). It was observed that the levels of Hg, BUN, urine protein, GSH, and MDA and activities of NAG, ALP, and LDH increased significantly; the activities of SOD and GSH-Px decreased significantly; the levels of ROS and apoptosis increased obviously; and many pathological changes occurred dose-dependently in the HgCl(2) injection groups. Further investigation indicated that pretreatment with TP and Sch B significantly reversed the toxic effects of HgCl(2). These results suggested that TP and Sch B might antagonize the nephrotoxicity caused by HgCl(2) exposure.

Self-selection in the self-assembly of isomeric supramolecular squares from unsymmetrical bis(4-pyridyl)acetylene ligands.

A new approach wherein steric interactions between substituents of unsymmetrical bis(4-pyridyl)acetylene ligands dictate the self-selection of single isomers of [4 + 4] self-assembled squares is presented. Each [4 + 4] self-assembly is characterized by multinuclear (31)P and (1)H NMR spectroscopies and electrospray ionization mass spectrometry. NMR spectroscopic studies are used to provide a means of evaluating the efficiency of bulky substituents at proximal or remote positions relative to the Pt-N bonding motif to direct self-selection. Molecular modeling using the MMFF force field is utilized to determine the relative energy of different isomers of each assembly, and modeling results reasonably explain the trend in self-selectivity with varying pyridyl substitution.

[Effects of perioperative administration of Rhubarb on acute inflammatory response in patients with gastric cancer].

OBJECTIVE: To observe the effect of perioperative administration of rhubarb on the acute inflammatory response in patients with gastric cancer. METHODS: In this prospective, single-blinded, controlled clinical trial, thirty-one patients with gastric cancer operatively treated were randomly divided into two groups, with 14 patients in control group and 17 in study group. Patients in both groups were given an isocaloric and isonitrogenous enteral diet. The enteral diet was started 36 hours after operation, and continued for 6 days. Patients in the study group were fed with rhubarb before operation, and at 1 day and 2 days after operation. Indexes of acute inflammatory response such as serum C-reactive protein (CRP), interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-alpha), and indexes of nutritional status such as serum albumin (ALB), prealbumin (PA) and transferrin (TRF) were measured before operation, and at 1 day, 3 and 7 days after operation. RESULTS: Patients in both groups had acute inflammatory response, and the indexes of nutritional status decreased after operation.IL-6, CRP and TNF-alpha tested at 3 and 7 days after operation were lower in the study group as compared with those in the control group, and the recovery time of gastrointestinal motility such as borborygmus, gas elimination and defecation was shorter in the study group as compared with that in the control group. The indexes of nutritional status showed no significant differences between two groups after operation. CONCLUSION: Rhubarb can positively modulate the acute inflammatory response, promote the recovery of postoperative gastrointestinal motility, and benefit enteral nutrition support in patients who have undergone major operations for gastric cancer.

Long-term efficacy of slow-pathway catheter ablation in patients with documented but noninducible supraventricular tachycardia.

BACKGROUND: The long-term efficacy of radiofrequency catheter ablation of slow pathway in patients with dual atrioventricular node pathway and a documented but noninducible paroxysmal supraventricular tachycardia (PSVT) is not entirely clear. METHODS: Forty nine patients (Group A) with documented but noninducible PSVT and dual atrioventricular node pathway were prospectively studied. Programmed electrical stimulation induced a single atrioventricular node echo beat in 13 patients, and double echo beats in 9 at baseline or during isoproterenol infusion. Clinical and electrophysiological characteristics of Group A patients were compared with that of age- and gender-matched patients with dual atrioventricular node pathway but inducible PSVT (Group B). RESULTS: There was no significant difference in the electrophysiological properties of the fast and slow pathways between the two groups. Catheter ablation eliminated the slow pathway in all patients. There was no recurrence of PSVT in either Group A or Group B during the follow-up of 38 +/- 5 months. CONCLUSIONS: In patients with dual atrioventricular node pathway and a documented but noninducible PSVT, catheter ablation of slow pathway is highly effective in preventing tachycardia in long term.