Schisandrin B, a dual positive allosteric modulator of GABAA and glycine receptors, alleviates seizures in multiple mouse models.

Epilepsy is a prevalent and severe neurological disorder and approximately 30% of patients are resistant to existing medications. It is of utmost importance to develop alternative therapies to treat epilepsy. Schisandrin B (SchB) is a major bioactive constituent of Schisandra chinensis (Turcz.) Baill and has multiple neuroprotective effects, sedative and hypnotic activities. In this study, we investigated the antiseizure effect of SchB in various mouse models of seizure and explored the underlying mechanisms. Pentylenetetrazole (PTZ), strychnine (STR), and pilocarpine-induced mouse seizure models were established. We showed that injection of SchB (10, 30, 60 mg/kg, i.p.) dose-dependently delayed the onset of generalized tonic-clonic seizures (GTCS), reduced the incidence of GTCS and mortality in PTZ and STR models. Meanwhile, injection of SchB (30 mg/kg, i.p.) exhibited therapeutic potential in pilocarpine-induced status epilepticus model, which was considered as a drug-resistant model. In whole-cell recording from CHO/HEK-239 cells stably expressing recombinant human GABAA receptors (GABAARs) and glycine receptors (GlyRs) and cultured hippocampal neurons, co-application of SchB dose-dependently enhanced GABA or glycine-induced current with EC50 values at around 5 µM, and application of SchB (10 µM) alone did not activate the channels in the absence of GABA or glycine. Furthermore, SchB (10 µM) eliminated both PTZ-induced inhibition on GABA-induced current (IGABA) and strychnine (STR)-induced inhibition on glycine-induced current (Iglycine). Moreover, SchB (10 µM) efficiently rescued the impaired GABAARs associated with genetic epilepsies. In addition, the homologous mutants in both GlyRs-α1(S267Q) and GABAARs-α1(S297Q)ß2(N289S)γ2L receptors by site-directed mutagenesis tests abolished SchB-induced potentiation of IGABA and Iglycine. In conclusion, we have identified SchB as a natural positive allosteric modulator of GABAARs and GlyRs, supporting its potential as alternative therapies for epilepsy.

Pharmacognostic profiles, evaluation of analgesic, anti-inflammatory and anticonvulsant activities of Newbouldia laevis (P. Beauv.) Seem. ex Bureau leaf and root extracts in Wistar rats.

ETHNOPHARMACOLOGICAL RELEVANCE: Newbouldia laevis is a popular medicinal plant whose leaves and roots are used in Nigeria as ethnomedicinal prescriptions for pain, inflammation, convulsion, and epilepsy. These claims have not been scientifically verified prior to this study. AIM OF THE STUDY: To determine pharmacognostic profiles of the leaves and roots and evaluate the analgesic, anti-inflammatory, and anticonvulsant activities of methanol leaf and root extracts in Wistar rats. MATERIAL AND METHODS: The pharmacognostic profiles of the leaves and roots were determined using standard procedures to serve as fingerprints for the plant. The methanol leaf and root extracts of Newbouldia laevis were tested for acute toxicity using the OECD's up and down method at the maximum dose of 2000 mg/kg (orally) in Wistar rats. Analgesic studies were carried out in acetic acid-induced writhing in rats and tail immersion. The anti-inflammatory activity of the extracts was evaluated using carrageenan-induced rat paw-oedema and formalin-induced inflammation in rats' mode. The anticonvulsant activity was determined using strychnine-induced, pentylenetetrazol-induced, and maximal electroshock-induced rat convulsion models. For each of these studies, the extracts doses of 100, 200 and 400 mg/kg were administered to the rats following the oral route. RESULTS: The pharmacognostic profiles showed that the leaves possessed deep-sunken paracytic stomata (5-8-16 mm2; adaxial, 8-11-24 mm2; abaxial epidermis), vein islets (2-4-10 mm2; adaxial), vein terminations (10-14-18 mm2; adaxial), palisade ratio (8.3-12.5-16.4 mm2; adaxial, 2.5-6.8-12.2 mm2; adaxial), covering unicellular trichome (8-14; adaxial), spheroidal calcium oxalate crystals (3-5 µm), and oval-shaped striated starch grain with no hilum (0.5-4.3 µm). The transverse section of the leaf showed the presence of spongy and palisade parenchyma as well as a closed vascular bundle. The root powder showed the presence of brachy sclereid, fibers without lumen, and lignin. All physicochemical parameters fall within the acceptable limits, phytochemical contents showed mainly glycosides, alkaloids, and steroids while acute oral toxicity (LD50) of the parts for 14 days did not produce any toxicity signs or mortality in the rats. The extracts produced dose-dependent (100-400 mg/kg) analgesic involving opioid receptors, anti-inflammatory, and anticonvulsant activities in the rats which were significant (p ≤ 0.05) when compared to the standard drugs. The leaf extract possessed the most potent analgesic and anti-inflammatory effects in the rats, while the most anticonvulsant effects were observed in rats treated with the leaf extract. Both extracts showed elevated levels of protection against strychnine-induced, pentylenetetrazol-induced, and maximal electroshock-induced seizure in rats. CONCLUSION: Our study revealed some pharmacognostic profiles of Newbouldia laevis leaves and roots that are vital for its identification from closely related species often used for adulteration in traditional medicine. The study further showed that the leaf and root extracts of the plant possessed dose-dependent analgesics, anti-inflammatory and anti-convulsant activities in rats, thus, justifying its use for the treatment of these diseases in Nigerian traditional medicine. There is a need to further study its mechanisms of action towards drug discovery.

Revealing the most effective anticonvulsant part of Malvaviscus arboreus Dill. Ex Cav. and its acute and sub-acute toxicity.

ETHNOPHARMACOLOGY RELEVANCE: Different parts of Malvaviscus arboreus Dill. Ex Cav. (M. arboreus) are traditionally used in the West Region of Cameroon to treat many diseases, including epilepsy. AIM OF THE STUDY: To determine which part of M. arboreus offers the best anticonvulsant effect, and to assess the acute and sub-acute toxicity of the part of interest. MATERIALS AND METHODS: the anticonvulsant effect of the aqueous lyophilisate of the decoction of flowers, leaves, stems and roots of M. arboreus at various doses was evaluated and compared on the model of acute epileptic seizures induced by pentylenetetrazole (PTZ) (70 mg/kg), injected 1 h after oral administration of the various extracts. Out of these plant parts, the leaves were then selected to prepare the hydroethanolic extract and its anticonvulsant effect against PTZ at the doses of 122.5, 245 and 490 mg/kg, as well as its acute toxicity were compared with those of the aqueous lyophilisate of the leaves. The anticonvulsant effect of the aqueous lyophilisate of M. arboreus leaves was further evaluated on models of acute epileptic seizures induced by picrotoxin (PIC) (7.5 mg/kg), strychnine (STR) (2.5 mg/kg) and pilocarpine (350 mg/kg). The 28 days sub-acute toxicity, as well as the quantitative phytochemistry and the in vitro antioxidant potential (FRAP, DPPH, ABTS+) of the aqueous lyophilisate of the leaves of M. arboreus were also evaluated. RESULTS: M. arboreus leaves showed the best anticonvulsant effect and the aqueous lyophilisate was the best extract. The latter significantly protected the animals against convulsions induced by PTZ (71.43%) (p < 0.01), PIC (57.14%) (p < 0.05) and STR (42%) and had no effect on pilocarpine-induced seizures. Furthermore, it showed no acute or sub-acute toxicity, and revealed a high content of flavonoids, saponins, tannins and alkaloids, and antioxidant activity in vitro. CONCLUSION: The aqueous lyophilisate of the leaves of M. arboreus offers the best anticonvulsant effect on the extraction solvent used, and it would act mainly via a potentiation of the inhibitory systems of the brain (GABA, Glycine). In addition, its richness in bioactive compounds gives it an antioxidant potential, and it is not toxic in acute and sub-acute toxicity. All this justifies at least in part its empirical uses, and makes M. arboreus a candidate for the alternative treatment of epilepsy.

ATF3 contributes to brucine-triggered glioma cell ferroptosis via promotion of hydrogen peroxide and iron.

Ferroptotic cell death is characterized by iron-dependent lipid peroxidation that is initiated by ferrous iron and H2O2 via Fenton reaction, in which the role of activating transcription factor 3 (ATF3) remains elusive. Brucine is a weak alkaline indole alkaloid extracted from the seeds of Strychnos nux-vomica, which has shown potent antitumor activity against various tumors, including glioma. In this study, we showed that brucine inhibited glioma cell growth in vitro and in vivo, which was paralleled by nuclear translocation of ATF3, lipid peroxidation, and increases of iron and H2O2. Furthermore, brucine-induced lipid peroxidation was inhibited or exacerbated when intracellular iron was chelated by deferoxamine (500 µM) or improved by ferric ammonium citrate (500 µM). Suppression of lipid peroxidation with lipophilic antioxidants ferrostatin-1 (50 µM) or liproxstatin-1 (30 µM) rescued brucine-induced glioma cell death. Moreover, knockdown of ATF3 prevented brucine-induced accumulation of iron and H2O2 and glioma cell death. We revealed that brucine induced ATF3 upregulation and translocation into nuclei via activation of ER stress. ATF3 promoted brucine-induced H2O2 accumulation via upregulating NOX4 and SOD1 to generate H2O2 on one hand, and downregulating catalase and xCT to prevent H2O2 degradation on the other hand. H2O2 then contributed to brucine-triggered iron increase and transferrin receptor upregulation, as well as lipid peroxidation. This was further verified by treating glioma cells with exogenous H2O2 alone. Moreover, H2O2 reversely exacerbated brucine-induced ER stress. Taken together, ATF3 contributes to brucine-induced glioma cell ferroptosis via increasing H2O2 and iron.

Autophagy Impairment through Lysosome Dysfunction by Brucine Induces Immunogenic Cell Death (ICD).

Autophagy is an important tightly controlled cellular process that regulates cellular homeostasis and is involved in deciding cell fate such as cell survival and death. The role of autophagy in many intracellular signaling pathways explains its interaction with other different types of cell death, including apoptosis and immunogenic cell death (ICD). The reports showed the complex and intriguing relationship existing between autophagy and immune system signaling pathways. However, the role of autophagy in ICD remains to be clearly elucidated. In this study, we demonstrated that Brucine, a clinically-used small molecule in traditional Chinese medicine, elicited autophagy inhibition. Brucine also triggered cell stress and induced features of ICD, including calreticulin (CRT) exposure and high-mobility group box 1 (HMGB1) release in MDA-MB-231 and CT26 cancer cells. Brucine impaired autolysosomal degradation and exerted a feedback regulation of ERK1/2-mTOR-p70S6K signaling cascade. Brucine-elicited ICD was confirmed by the rejection of CT26 tumor cells, implanted in the mice after vaccination with Brucine-treated CT26 cells. The impaired autophagy contributed to Brucine-induced ICD, as knock-down of Atg5 significantly reduced Brucine-elicited CRT exposure and HMGB1 release. Our results revealed Brucine as a novel autophagy regulator, ICD inducer and hitherto undocumented role of autophagy in ICD. Thus, these results imply the importance of Brucine in cancer immunotherapy. Therefore, Brucine may be used as an ICD inducer and improve its application in cancer treatment with minimized toxicity.

Brucine alleviates neuropathic pain in mice via reducing the current of the sodium channel.

ETHNOPHARMACOLOGICAL RELEVANCE: Strychnos nux-vomica L. (Loganiaceae) is grown extensively in South Asian. The dried seed of this plant, nux vomica, has been clinically used in Chinese medicine for relieving rheumatic pain, reducing swelling and treating cancer. Brucine, the second abundant alkaloid constituent of nux vomica, shows excellent clinical therapeutic effect, especially in relieving pain, but mechanism of brucine in relieving pain is still unclear. AIM OF THE STUDY: Explore the analgesic effect of brucine, reveal the molecular mechanism of brucine analgesia. MATERIALS AND METHODS: Antinociceptive effects of brucine were assessed in acute and chronic pain mice model. Electrophysiological experiments were used to evaluate the effects of brucine on neuronal activity and sodium channel function. RESULTS: In acute pain models, brucine significantly inhibits response induced by nociceptive heat and mechanical stimulation. Furthermore, thermal hypersensitivity and mechanical allodynia were also alleviated by brucine treatment in a chronic constriction injury (CCI) mouse model. Sodium channel plays a crucial role in neuropathic pain. Electrophysiological results show that brucine inhibits the excitability of DRG neurons directly, the number of action potential (AP) was significantly reduced after brucine treatment, and this kind of inhibition is due to brucine inhibits both tetrodotoxin-sensitive (TTXs) and tetrodotoxin-resistant (TTXr) sodium channel. CONCLUSIONS: Taken together, brucine is a novel drug candidate in treating acute and chronic pain diseases, which might be attributed to inhibition the excitability of sodium channel directly.

Brucine suppresses breast cancer metastasis via inhibiting epithelial mesenchymal transition and matrix metalloproteinases expressions.

OBJECTIVE: To examine the effect of brucine on the migration, invasion, adhesion and expressions of epithelial-to-mesenchymal transition (EMT) markers and matrix metalloproteinases (MMPs) in the highly metastatic breast cancer cell lines MDA-MB-231 and Hs578-T. METHODS: MDA-MB-231 and Hs578-T cells were divided to 4 groups: the control group (0.1% DMSO), and 25, 50 and 100 µmol/L brucine groups. The cell viability was determined using a CellTiter-Glo® luminescent cell viability. The scratch wound healing assay and tanswell migration assay were used to determine the migration ability of these cells treated by different concentrations of brucine. The proliferation rate, invasive potential and adhesive ability were respectively performed by colony formation assay, transwell invasion assay and adhension assay. The protein and mRNA expressions of EMT biomarkers, MMP-2 and MMP-9 were investigated by real-time reverse transcription polymerase chain reaction and Western blot. RESULTS: Compared with the control group, brucine had little effect on cell viability or proliferation (P>0.05), but led to a dose-dependent decrease on migration, invasion, adhension of MDA-MB-231 and Hs578-T cells (P<0.01). Furthermore, brucine increased the protein and mRNA levels of EMT markers such as E-cadherin and ß-catenin in MDA-MB-231 and Hs578-T cells, and decreased the protein and mRNA levels of mesenychmal markers such as vimentin and fibronectin, as well as the expressions of MMP-2 and MMP-9 (all P<0.01). CONCLUSION: Brucine inhibited triple negative breast cancer cells metastasis potentially through EMT reversion and MMP-2 and MMP-9 inhibition.

Brucine inhibits bone metastasis of breast cancer cells by suppressing Jagged1/Notch1 signaling pathways.

OBJECTIVE: To examine the effects of brucine on the invasion, migration and bone resorption of receptor activator of nuclear factor-kappa B ligand (RANKL)-induced osteoclastogenesis. METHODS: The osteoclastogenesis model was builded by co-culturing human breast tumor MDA-MB-231 and mouse RAW264.7 macrophages cells. RANKL (50 ng/mL) and macrophage-colony stimulating factor (50 ng/mL) were added to this system, followed by treatment with brucine (0.02, 0.04 and 0.08 mmol/L), or 10 µmol/L zoledronic acid as positive control. The migration and bone resorption were measured by transwell assay and in vitro bone resorption assay. The protein expressions of Jagged1 and Notch1 were investigated by Western blot. The expressions of transforming growth factor-ß1 (TGF-ß1), nuclear factor-kappa B (NF-κB) and Hes1 were determined by enzyme-linked immunosorbent assay. RESULTS: Compared with the model group, brucine led to a dose-dependent decrease on migration of MDA-MB-231 cells, inhibited RANKL-induced osteoclastogenesis and bone resorption of RAW264.7 cells (P<0.01). Furthermore, brucine decreased the protein levels of Jagged1 and Notch1 in MDA-MB-231 cells and RAW264.7 cells co-cultured system as well as the expressions of TGF-ß1, NF-κB and Hes1 (P<0.05 or P<0.01). CONCLUSION: Brucine may inhibit osteoclastogenesis by suppressing Jagged1/Notch1 signaling pathways.

Contribution of GABAA, Glycine, and Opioid Receptors to Sacral Neuromodulation of Bladder Overactivity in Cats.

In α-chloralose-anesthetized cats, we examined the role of GABAA, glycine, and opioid receptors in sacral neuromodulation-induced inhibition of bladder overactivity elicited by intravesical infusion of 0.5% acetic acid (AA). AA irritation significantly (P < 0.01) reduced bladder capacity to 59.5 ± 4.8% of saline control. S1 or S2 dorsal root stimulation at threshold intensity for inducing reflex twitching of the anal sphincter or toe significantly (P < 0.01) increased bladder capacity to 105.3 ± 9.0% and 134.8 ± 8.9% of saline control, respectively. Picrotoxin, a GABAA receptor antagonist administered i.v., blocked S1 inhibition at 0.3 mg/kg and blocked S2 inhibition at 1.0 mg/kg. Picrotoxin (0.4 mg, i.t.) did not alter the inhibition induced during S1 or S2 stimulation, but unmasked a significant (P < 0.05) poststimulation inhibition that persisted after termination of stimulation. Naloxone, an opioid receptor antagonist (0.3 mg, i.t.), significantly (P < 0.05) reduced prestimulation bladder capacity and removed the poststimulation inhibition. Strychnine, a glycine receptor antagonist (0.03-0.3 mg/kg, i.v.), significantly (P < 0.05) increased prestimulation bladder capacity but did not reduce sacral S1 or S2 inhibition. After strychnine (0.3 mg/kg, i.v.), picrotoxin (0.3 mg/kg, i.v.) further (P < 0.05) increased prestimulation bladder capacity and completely blocked both S1 and S2 inhibition. These results indicate that supraspinal GABAA receptors play an important role in sacral neuromodulation of bladder overactivity, whereas glycine receptors only play a minor role to facilitate the GABAA inhibitory mechanism. The poststimulation inhibition unmasked by blocking spinal GABAA receptors was mediated by an opioid mechanism.

Brucine suppresses ethanol intake and preference in alcohol-preferring Fawn-Hooded rats.

AIM: Brucine (BRU) extracted from the seeds of Strychnos nux-vomica L is glycine receptor antagonist. We hypothesize that BRU may modify alcohol consumption by acting at glycine receptors, and evaluated the pharmacodynamic profiles and adverse effects of BRU in rat models of alcohol abuse. METHODS: Alcohol-preferring Fawn-Hooded (FH/Wjd) rats were administered BRU (10, 20 or 30 mg/kg, sc). The effects of BRU on alcohol consumption were examined in ethanol 2-bottle-choice drinking paradigm, ethanol/sucrose operant self-administration paradigm and 5-d ethanol deprivation test. In addition, open field test was used to assess the general locomotor activity of FH/Wjd rats, and conditioned place preference (CPP) was conducted to assess conditioned reinforcing effect. RESULTS: In ethanol 2-bottle-choice drinking paradigm, treatment with BRU for 10 consecutive days dose-dependently decreased the ethanol intake associated with a compensatory increase of water intake, but unchanged the daily total fluid intake and body weight. In ethanol/sucrose operant self-administration paradigms, BRU (30 mg/kg) administered before each testing session significantly decreased the number of lever presses for ethanol and the ethanol intake, without affecting the number of sucrose (10%) responses, total sucrose intake, and the number of lever presses for water. Acute treatment with BRU (30 mg/kg) completely suppressed the deprivation-induced elevation of ethanol consumption. Treatment with BRU (10, 20, and 30 mg/kg) did not alter locomotion of FH/Wjd rats, nor did it produce place preference or aversion. CONCLUSION: BRU selectively decreases ethanol consumption with minimal adverse effects. Therefore, BRU may represent a new pharmacotherapy for alcoholism.

Inhibition of Glioblastoma Cell Growth In Vitro and In Vivo by Brucine, a Component of Chinese Medicine.

Glioblastoma multiforme (GBM) is one of the most common glial cell tumors and has drawn more and more attention in the clinic in recent years. Brucine has been reported to significantly suppress gastric cancer, lung cancer, and prostate cancer growth in vivo by inducing cell apoptosis. Here, the effects of brucine on U251 human glioma cell growth were investigated in vitro by cell proliferation assay, FACs, and qPCR in a xenograft tumor model. Treatment with brucine reduced the expression of BCL-2 and cyclooxygenase-2 (COX-2), while upregulated BAX expression in U251 human glioma cells resulted in reduced glioma cell survival rate and inhibited the growth of xenograft tumors. We concluded that brucine has a suppressive effect on U251 human glioma cells in vitro and in vivo, which could help in understanding the role of brucine in glioma cells and guiding drug use in the clinic.

Brucine, an alkaloid from seeds of Strychnos nux-vomica Linn., represses hepatocellular carcinoma cell migration and metastasis: the role of hypoxia inducible factor 1 pathway.

Brucine is an alkaloid derived from the seeds of Strychnos nux-vomica Linn. which have long been used as a traditional medicine for the treatment of hepatocellular carcinoma (HCC) in China. HCC prognosis can be greatly influenced by metastasis. There has thus far been little research into brucine as a source of anti-metastasis activity against HCC. In this study, we revealed that brucine dramatically repressed HepG2 and SMMC-7721 HCC cell migration with few cytotoxic effects. Hypoxia inducible factor 1 (HIF-1) is a key transcription factor mediating cell migration and invasion. Brucine suppressed HIF-1-dependent luciferase activity in HepG2 cells. The transcriptions of four known HIF-1 target genes involved in HCC metastasis, i.e., fibronectin, matrix metallopeptidase 2, lysyl oxidase, and cathepsin D, were also attenuated after brucine treatment. Experiments in vivo showed that an intraperitoneal injection of 5 and 15 mg/kg of brucine resulted in dose-dependent decreases in the lung metastasis of H22 ascitic hepatoma cells. Moreover, a dosage of brucine at 15 mg/kg exhibited very low toxic effects to tumor-bearing mice. Consistently, brucine downregulated expression levels of HIF-1 responsive genes in vivo. Our current study demonstrated the capacity of brucine in suppressing HCC cell migration in vitro and lung metastasis in vivo. The inhibition of the HIF-1 pathway is implicated in the anti-metastasis activity of brucine.

Evaluation of the pharmacodynamics and pharmacokinetics of brucine following transdermal administration.

Before the design of brucine-containing transdermal formulations, the pharmacodynamics and pharmacokinetics of brucine following transdermal administration should be evaluated. In this study, the effect of addition of ethanol on solubility of bruicne was investigated and 20% ethanol was added into PBS to obtain 10mg/mL brucine solution. Then three transdermal doses (10, 20 and 40 mg/kg) were administered to mice to evaluate pharmacological activity. It had been demonstrated that brucine possessed analgesic and anti-inflammatory activity in a dose-dependent manner. Cytotoxicities of brucine against various tumor cells including skin tumor cell were also compared in vitro. Brucine was found to possess antitumor activity in a concentration and time-dependent manner and gastrointestinal tumor cells seemed to be more sensitive to brucine. Then in vitro skin permeation behavior and in vivo pharmacokinetics following transdermal administration were further investigated. The cumulative amounts of brucine across mouse skin in vitro were found to be higher than 90%. The absolute bioavailability of brucine was determined to be 40.83%. And compared with intravenous administration, MRT and T1/2 values were increased about 8~12-fold by transdermal route. Moreover, fluctuations of drug levels were found to be significantly decreased in tissues, especially in brain. Finally, no dermal toxicity of brucine was observed. The results of this study indicated that transdermal administration might be beneficial for the sustained efficacy and reduced toxicity of brucine.

Changes in brain cortex sensitivity to epileptogens under conditions of ketogenic diet.

The epileptogenic effects of applications of NMDA and kainic acid solutions to the frontal cortex were attenuated in rats receiving ketogenic diet (80% lipids, 3.3% carbohydrates, and 16.7% proteins) during 4 weeks. Spike latency increased, the power of focal epileptic activity decreased, and focus lifetime was shortened in these animals. Sodium benzylpenicillin and strychnine nitrate less markedly reduced epileptogenic activity.

Effects of brucine on vascular endothelial growth factor expression and microvessel density in a nude mouse model of bone metastasis due to breast cancer.

OBJECTIVE: To study the effects of brucine on vascular endothelial growth factor (VEGF) expression and microvessel density (MVD) in a nude mouse model of bone metastasis due to breast cancer, and to assess the possible antitumor mechanism of brucine. METHODS: A syringe needle was used to directly inject 0.2 mL monoplast suspension (with 2×10(5) human breast cancer cells contained) into the bony femoral cortex of the right hind leg for modeling. Twenty-five nude mice were randomized into five groups and administered with an intraperitoneal injection of saline or drug for 8 consecutive days: model group (0.2 mL normal saline), low-dose brucine group (1.73 mg·kg(-1)), medium-dose brucine group (3.45 mg·kg(-1)), high-dose brucine group (6.90 mg·kg(-1)), and thalidomide group (200 mg·kg(-1)). Diet and activity were recorded, and the tumors were harvested 5 weeks later. The percentage of VEGF-positive cells was determined with hematoxylin and eosin staining and immunohistochemical staining, and MVD expression was determined by optical microscopy. RESULTS: The VEGF expressions in brucine- or thalidomide-treated mice were significantly reduced as compared with mice in the model group (P <0.01). There were no significant difference between the high-dose brucine group and the thalidomide group (P >0.05). Significant difference was between the high- and low-dose brucine group P<0.05). Further, VEGF expression was significantly increased in the low- and medium-dose brucine groups compared with the thalidomide group (P <0.05). The MVD values in the three brucine and thalidomide groups were significantly lower than that in the model group (P <0.01). The MVD values in the medium- and high-dose brucine groups were not significantly different from those in the thalidomide group (P >0.05), while the MVD value showed a significant increase in the low-dose group compared with the thalidomide group (P <0.05). CONCLUSION: Brucine could inhibit the growth of breast cancer to bone metastases, possibly by inhibiting tumor angiogenesis.

Glycine inhibitory dysfunction turns touch into pain through astrocyte-derived D-serine.

Glycine inhibitory dysfunction provides a useful experimental model for studying the mechanism of dynamic mechanical allodynia, a widespread and intractable symptom of neuropathic pain. In this model, allodynia expression relies on N-methyl-d-aspartate receptors (NMDARs), and it has been shown that astrocytes can regulate their activation through the release of the NMDAR coagonist d-serine. Recent studies also suggest that astrocytes potentially contribute to neuropathic pain. However, the involvement of astrocytes in dynamic mechanical allodynia remains unknown. Here, we show that after blockade of glycine inhibition, orofacial tactile stimuli activated medullary dorsal horn (MDH) astrocytes, but not microglia. Accordingly, the glia inhibitor fluorocitrate, but not the microglia inhibitor minocycline, prevented allodynia. Fluorocitrate also impeded activation of astrocytes and blocked activation of the superficial MDH neural circuit underlying allodynia, as revealed by study of Fos expression. MDH astrocytes are thus required for allodynia. They may also produce d-serine because astrocytic processes were selectively immunolabeled for serine racemase, the d-serine synthesizing enzyme. Accordingly, selective degradation of d-serine with d-amino acid oxidase applied in vivo prevented allodynia and activation of the underlying neural circuit. Conversely, allodynia blockade by fluorocitrate was reversed by exogenous d-serine. These results suggest the following scenario: removal of glycine inhibition makes tactile stimuli able to activate astrocytes; activated astrocytes may provide d-serine to enable NMDAR activation and thus allodynia. Such a contribution of astrocytes to pathological pain fuels the emerging concept that astrocytes are critical players in pain signaling. Glycine disinhibition makes tactile stimuli able to activate astrocytes, which may provide d-serine to enable NMDA receptor activation and thus allodynia.

Safety of individual medication of Ma Qian Zi (semen strychni) based upon assessment of therapeutic effects of Guo's therapy against moderate fluorosis of bone.

OBJECTIVE: To assess the safety of individual medication of Guo's Ma Qian Decoction on the basis of effective treatment of fluorosis of bone with Guo's therapy. METHODS: One hundred and fourteen cases of moderate fluorosis of bone were randomly divided into a treatment group (n = 60) and a control group (n = 54) between December 2007 and August 2009 by using the block randomized method and a central random system. At the same time of basic treatment, the patients in the treatment group were orally administrated with Guo's Ma Qian Decoction. The initial dose of Ma Qian Zi (Semen Strychni) was 0.4 g and increased by 0.05 g every two days, with the doses of other drugs unchanged, until the patient had "nux vomica response". For the patients with no "nux vomica response", the dosage was continued to increase and the maximum dosage was not more than 1.2 g/day. The control group was treated with decoction placebo. The changes of strychnine and brucine contents before and after processing and after decoction of Ma Qian Zi (Semen Strychni) were determined with reversed-phase high-performance liquid chromatography, which were controlled within ranges stipulated in the Pharmacopeia; Adverse events were analyzed; Blood strychnine and brucine contents in 10 cases who had taken the drugs were determined. RESULTS: 1) Strychnine (2.125%) and brucine (1.425%) contents before processing of Ma Qian Zi and 1.88% and 1.31% after processing all conformed with the standards of strychnine (1.2-2.2%) and brucine (no less than 0.8%) stipulated in the Pharmacopeia. When the maximum dosage of Ma Qian Zi was 1.2 g/day, strychnine in the decoction was 11.17 mg and brucine was 7.44 mg, which all conformed with the maximum limited amount (strychnine 13.32 and brucine no less than 4.8 mg) stipulated in the Pharmacopeia. 2) Eight cases had "nux vomica response" in the treatment group and one case in the control group, with a significant difference between the two groups (P < 0.05). 3) Altogether 18 cases had adverse events, with an incidence rate of 15.38% (8 cases) in the treatment group and 18.52% (10 cases) in the control group, with no difference between the two groups (P > 0.05); Among them, 10 cases (8.77%) with the adverse event were not related with therapeutic drugs, with an incidence rate of 6.67% (4 cases) in the treatment and 11.11% (6 cases) in the control group, with no significant difference between the two groups (P > 0.05). Seven cases had suspicious relative adverse events, the risk in the treatment group was 0.658 times of the control group, with no significant difference (P > 0.05), and one case had the toxic reaction of nux-vomica seed. 4) Strychnine and brucine were unable to be detected in the blood in all points of time in the 10 cases who had taken the drugs, indicating that plasma strychnine and brucine contents were lower than the minimum detectable amount (10 ng), and accumulation of strychnine and brucine were not found in blood of the patient during and after administration for 8 weeks. CONCLUSION: The individual medication of Ma Qian Zi (Semen Strychni) in the Guo's therapy has a better safety.

Modified porphyrin-brucine conjugated to gold nanoparticles and their application in photodynamic therapy.

Two porphyrin-brucine quaternary ammonium salts were immobilized on gold nanoparticles and their suitability for both in vitro and in vivo photodynamic therapy (PDT) was assayed using the basaloid squamous cell carcinoma PE/CA-PJ34 cell line. In vitro PDT experiments revealed that the gold nanoparticle-bound conjugates were less effective than unbound conjugates in killing cells. However, the same conjugates were more effective in reducing tumor size in vivo, with complete tumor regression observed.

Ayurvedic processed seeds of nux-vomica: neuropharmacological and chemical evaluation.

The effect of detoxification on Strychnos nux-vomica seeds by traditional processing with aloe and ginger juices (B), by frying in cow ghee (C), and by boiling in cow milk (D) was investigated. The ethanolic extracts of these samples were subjected to spontaneous motor activity (SMA), pentobarbitone-induced hypnosis, PTZ induced convulsions, diazepam-assisted protection, and morphine-induced catalepsy. All samples reduced SMA and inhibited catalepsy. The seeds processed in milk (D) showed the lowest strychnine content in the cotyledons, exhibited marked inhibition of PTZ induced convulsions and maximal potentiation of hypnosis, and were the safest (LD(50)).