Anaesthetic-sparing effect of the anxiolytic drug tasipimidine in Beagle dogs.

OBJECTIVE: To evaluate the effect of oral tasipimidine on dog handling, ease of catheter placement and propofol and isoflurane requirements for anaesthesia. STUDY DESIGN: Placebo-controlled, randomized, blinded, experimental trial. ANIMALS: A group of seven adult Beagle dogs weighing (mean ± standard deviation) 13.1 ± 2.7 kg with a mean age of 18.6 ± 1 months. METHODS: The dogs underwent four treatments before induction of anaesthesia with propofol. PP: placebo orally (PO) 60 minutes before induction of anaesthesia followed by placebo (NaCl 0.9%) intravenously (IV). TP: tasipimidine 30 µg kg-1 (PO) 60 minutes before induction of anaesthesia followed by placebo (NaCl 0.9%) IV. TMP: tasipimidine 30 µg kg-1 PO 60 minutes before induction of anaesthesia followed by methadone 0.2 mg kg-1 IV. TMPD: tasipimidine 30 µg kg-1 PO 60 minutes before induction of anaesthesia followed by methadone 0.2 mg kg-1 and dexmedetomidine 1 µg kg-1 IV followed by a dexmedetomidine constant rate infusion of 1 µg kg-1 hour-1. Sedation, response to catheter placement, intubation quality, time to loss of consciousness, time to intubation, required dose of propofol and minimum alveolar isoflurane concentration preventing motor movement (MACNM) were determined. A mixed-model analysis or the Friedman and Mann-Whitney test were used; p-value < 0.05. RESULTS: Response to catheter placement did not differ between treatments. Tasipimidine alone reduced the propofol dose by 30%. Addition of methadone or methadone and dexmedetomidine reduced the propofol dose by 48% and 50%, respectively. Isoflurane MACNM was reduced by 19% in tasipimidine-medicated dogs, whereas in combination with methadone or methadone and dexmedetomidine, isoflurane MACNM was reduced by 35%. CONCLUSIONS AND CLINICAL RELEVANCE: An anxiolytic dose of tasipimidine induced mild signs of sedation in dogs and reduced propofol and isoflurane requirements to induce and maintain anaesthesia, which needs to be considered in an anaesthetic plan.

Effects of tasipimidine premedication with and without methadone and dexmedetomidine on cardiovascular variables during propofol-isoflurane anaesthesia in Beagle dogs.

OBJECTIVE: To evaluate cardiovascular effects of oral tasipimidine on propofol-isoflurane anaesthesia with or without methadone and dexmedetomidine at equianaesthetic levels. STUDY DESIGN: Prospective, placebo-controlled, blinded, experimental trial. ANIMALS: A group of seven adult Beagle dogs weighing (mean ± standard deviation) 12.4 ± 2.6 kg and a mean age of 20.6 ± 1 months. METHODS: The dogs underwent four treatments 60 minutes before induction of anaesthesia with propofol. PP: placebo orally and placebo (NaCl 0.9%) intravenously (IV); TP: tasipimidine 30 µg kg-1 orally and placebo IV; TMP: tasipimidine 30 µg kg-1 orally and methadone 0.2 mg kg-1 IV; and TMPD: tasipimidine 30 µg kg-1 orally with methadone 0.2 mg kg-1 and dexmedetomidine 1 µg kg-1 IV followed by 1 µg kg-1 hour-1. Isoflurane in oxygen was maintained for 120 minutes at 1.2 individual minimum alveolar concentration preventing motor movement. Cardiac output (CO), tissue blood flow (tbf), tissue oxygen saturation (stO2) and relative haemoglobin content were determined. Arterial and mixed venous blood gases, arterial and pulmonary artery pressures and heart rate (HR) were measured at baseline; 60 minutes after oral premedication; 5 minutes after IV premedication; 15, 30, 60, 90 and 120 minutes after propofol injection; and 30 minutes after switching the vaporiser off. Data were analysed by two-way anova for repeated measures; p < 0.05. RESULTS: Tasipimidine induced a significant 20-30% reduction in HR and CO with decreases in MAP (10-15%), tbf (40%) and stO2 (43%). Blood pressure and oxygenation variables were mainly influenced by propofol-isoflurane-oxygen anaesthesia, preceded by short-lived alterations related to IV methadone and dexmedetomidine. CONCLUSIONS AND CLINICAL RELEVANCE: Tasipimidine induced mild to moderate cardiovascular depression. It can be incorporated into a common anaesthetic protocol without detrimental effects in healthy dogs, when anaesthetics are administered to effect and cardiorespiratory function is monitored.

Cytisine eye drops for benzalkonium chloride-induced dry eye: safety and efficacy evaluation.

This experiment aimed to investigate the feasibility of cytisine (CYT) in treating eye diseases with ocular topical application. An in vitro cytotoxicity test, a hen's egg test-chorioallantoic membrane (HET-CAM), and a mouse eye tolerance test were used to fully reveal the ocular safety profiles of CYT. For the efficacy evaluations, CYT's effects on cell wound healing, against H2O2-induced oxidative stress damages on cells, and on benzalkonium chloride (BAC)-induced dry eye disease (DED) in mice were evaluated. Results showed that CYT did not show any cytotoxicities at concentrations no higher than 250 µg/ml, while lipoic acid (α-LA) at 250 µg/ml and BAC at 1.25 µg/ml showed significant cytotoxicities within 48 h incubation. The HET-CAM and mouse eye tolerance test confirmed that 0.5% CYT eye drops demonstrated good safety characteristics. Efficacy evaluations showed that CTY significantly promoted cell migration and wound healing. CYT significantly improved cell survival against H2O2-induced oxidative stress damage by reversing the imbalance between the reactive oxygen species (ROS) and antioxidant defense mechanisms. The animal evaluation of the BAC-induced dry eye model revealed that CYT demonstrated a strong treatment effect, including reversing ocular surface damages, recovering corneal sensitivity, and inhibiting neovascularization; HMGB1/NF-κB signaling was involved in this DED treatment by CTY. In conclusion, CYT had strong experimental treatment efficacy against DED with good ocular safety profiles, and it might be a novel and promising drug for DED.

Characterization of metabolic fate of phellodendrine and its potential pharmacological mechanism against diabetes mellitus by ultra-high-performance liquid chromatography-coupled time-of-flight mass spectrometry and network pharmacology.

RATIONALE: Characterizing the functional mechanism of quality control marker (Q-marker) was of great importance in revealing the primary pharmacological mechanism of herbs or the other complex system, and drug-related metabolites always contribute to the pharmacological functions. Cortex Phellodendri was used as a core herb in the treatment of diabetes mellitus (DM). As a Q-marker of Cortex Phellodendri, the role of phellodendrine in DM was still unclear. Thus, the characterization of phellodendrine-related metabolites in vivo and the subsequent induced functional mechanism exerted great importance in elucidating the anti-DM mechanism of Cortex Phellodendri. METHODS: An ultra-high-performance liquid chromatography-coupled time-of-flight mass spectrometry (UHPLC/Q-TOF MS) method was developed to profile metabolites of phellodendrine in rats. The potential pharmacological mechanism against DM was predicted by network pharmacology. RESULTS: A total of 19 phellodendrine-related metabolites were screened out in rats for the first time. Among them, M4, M5, M9, and M12 were regarded as the primary metabolites. Meanwhile, phase I metabolic reactions of hydroxylation, demethylation, and isomerization and phase II reactions of glucuronidation and sulfation occurred to phellodendrine; glucuronidation and hydroxylation were the two main metabolic reactions. Moreover, the potential targets of phellodendrine and three main metabolites (M4, M5, and M12) were predicted by a network pharmacological method, and they mainly shared 52 targets, including PDE5A, CHRNA3, SIGMAR1, F3, ESR1, DRD1, DRD2, DRD3, and DRD4. Furthermore, Kyoto Encyclopedia of Genes and Genomes pathway analysis showed that calcium signaling pathway, cGMP-PKG signaling pathway, and cAMP signaling pathway were regarded as the core mechanism of phellodendrine to treat DM. CONCLUSION: The metabolic feature of phellodendrine in vivo was revealed for the first time, and its anti-DM mechanism information for further pharmacological validations was also supplied. It also gave a direction to further elucidation of pharmacological mechanism of Cortex Phellodendri in treating DM.

Pharmacokinetics of dexmedetomidine during administration of vatinoxan in male neutered cats anesthetized with isoflurane.

Dexmedetomidine is an alpha-2 adrenoceptor agonist, and vatinoxan is an alpha-2 antagonist believed to poorly cross the blood-brain barrier in cats. Dexmedetomidine-vatinoxan combinations are of interest in anesthetized cats because the anesthetic sparing effect of dexmedetomidine may be preserved while vatinoxan attenuates the adverse cardiovascular effects of dexmedetomidine. The aim of this study was to characterize the pharmacokinetics of dexmedetomidine in cats during administration of isoflurane and vatinoxan. Six healthy adult male castrated cats were anesthetized with isoflurane in oxygen. Vatinoxan was administered using a target-controlled infusion system intended to maintain a plasma concentration of 4 µg/ml. Dexmedetomidine, 35 µg/kg was administered intravenously over 5 min. Plasma dexmedetomidine and vatinoxan concentrations were measured at selected time points ranging from prior to 8 hr after dexmedetomidine administration using liquid chromatography/tandem mass spectrometry. Compartment models were fitted to the time-concentration data using nonlinear mixed-effect modeling. A three-compartment model best fitted the data. Typical value (% interindividual variability) for the three-compartment volumes (ml/kg), the metabolic clearance and the two intercompartment distribution clearances (ml min-1 kg-1 ) were 168 (259), 318 (35), 1,425 (18), 12.4 (31), 39.1 (18), and 29.6 (17), respectively. Mean ± standard deviation plasma vatinoxan concentration was 2.6 ± 0.6 µg/ml.

Pharmacokinetics of vatinoxan in male neutered cats anesthetized with isoflurane.

OBJECTIVE: To characterize the pharmacokinetics of vatinoxan in isoflurane-anesthetized cats. STUDY DESIGN: Prospective experimental study. ANIMALS: A group of six adult healthy male neutered cats. METHODS: Cats were anesthetized using isoflurane in oxygen. Venous catheters were placed to administer the drug and sample blood. Vatinoxan, 1 mg kg-1, was administered intravenously over 5 minutes. Blood was sampled before and at various times during and up to 8 hours after vatinoxan administration. Plasma vatinoxan concentration was measured using liquid chromatography/tandem mass spectrometry. Compartment models were fitted to the time-concentration data using population methods and nonlinear mixed effect modeling. RESULTS: A three-compartment model best fitted the data. Typical value (% interindividual variability) for the three volumes (mL kg-1), the metabolic clearance and two distribution clearances (mL minute-1 kg-1) were 34 (55), 151 (35), 306 (18), 2.3 (34), 42.6 (25) and 5.6 (0), respectively. Hypotension increased the second distribution clearance to 10.6. CONCLUSION AND CLINICAL RELEVANCE: The pharmacokinetics of vatinoxan in anesthetized cats were characterized by a small volume of distribution and a low clearance. An intravenous bolus of 100 µg kg-1 of vatinoxan followed by constant rate infusions of 55 µg kg-1 minute-1 for 20 minutes, then 22 µg kg-1 minute-1 for 60 minutes and finally 10 µg kg-1 minute-1 for the remainder of the infusion time is expected to maintain the plasma concentration within 90%-110% of the plasma vatinoxan concentration previously shown to attenuate the cardiovascular effects of dexmedetomidine (25 µg kg-1) in conscious cats.

Concentrations of medetomidine enantiomers and vatinoxan, an α2-adrenoceptor antagonist, in plasma and central nervous tissue after intravenous coadministration in dogs.

OBJECTIVE: To quantify the peripheral selectivity of vatinoxan (L-659,066, MK-467) in dogs by comparing the concentrations of vatinoxan, dexmedetomidine and levomedetomidine in plasma and central nervous system (CNS) tissue after intravenous (IV) coadministration of vatinoxan and medetomidine. STUDY DESIGN: Experimental, observational study. ANIMALS: A group of six healthy, purpose-bred Beagle dogs (four females and two males) aged 6.5 ± 0.1 years (mean ± standard deviation). METHODS: All dogs were administered a combination of medetomidine (40 µg kg-1) and vatinoxan (800 µg kg-1) as IV bolus. After 20 minutes, the dogs were euthanized with an IV overdose of pentobarbital (140 mg kg-1) and both venous plasma and CNS tissues (brain, cervical and lumbar spinal cord) were harvested. Concentrations of dexmedetomidine, levomedetomidine and vatinoxan in all samples were quantified by liquid chromatography-tandem mass spectrometry and data were analyzed with nonparametric tests with post hoc corrections where appropriate. RESULTS: All dogs became deeply sedated after the treatment. The CNS-to-plasma ratio of vatinoxan concentration was approximately 1:50, whereas the concentrations of dexmedetomidine and levomedetomidine in the CNS were three- to seven-fold of those in plasma. CONCLUSIONS AND CLINICAL RELEVANCE: With the doses studied, these results confirm the peripheral selectivity of vatinoxan in dogs, when coadministered IV with medetomidine. Thus, it is likely that vatinoxan preferentially antagonizes α2-adrenoceptors outside the CNS.

Effects of intramuscular vatinoxan (MK-467), co-administered with medetomidine and butorphanol, on cardiopulmonary and anaesthetic effects of intravenous ketamine in dogs.

OBJECTIVE: To investigate the impact of intramuscular (IM) co-administration of the peripheral α2-adrenoceptor agonist vatinoxan (MK-467) with medetomidine and butorphanol prior to intravenous (IV) ketamine on the cardiopulmonary and anaesthetic effects in dogs, followed by atipamezole reversal. STUDY DESIGN: Randomized, masked crossover study. ANIMALS: A total of eight purpose-bred Beagle dogs aged 3 years. METHODS: Each dog was instrumented and administered two treatments 2 weeks apart: medetomidine (20 µg kg-1) and butorphanol (100 µg kg-1) premedication with vatinoxan (500 µg kg-1; treatment MVB) or without vatinoxan (treatment MB) IM 20 minutes before IV ketamine (4 mg kg-1). Atipamezole (100 µg kg-1) was administered IM 60 minutes after ketamine. Heart rate (HR), mean arterial (MAP) and central venous (CVP) pressures and cardiac output (CO) were measured; cardiac (CI) and systemic vascular resistance (SVRI) indices were calculated before and 10 minutes after MVB or MB, and 10, 25, 40, 55, 70 and 100 minutes after ketamine. Data were analysed with repeated measures analysis of covariance models. A p-value <0.05 was considered statistically significant. Sedation, induction, intubation and recovery scores were assessed. RESULTS: At most time points, HR and CI were significantly higher, and SVRI and CVP significantly lower with MVB than with MB. With both treatments, SVRI and MAP decreased after ketamine, whereas HR and CI increased. MAP was significantly lower with MVB than with MB; mild hypotension (57-59 mmHg) was recorded in two dogs with MVB prior to atipamezole administration. Sedation, induction, intubation and recovery scores were not different between treatments, but intolerance to the endotracheal tube was observed earlier with MVB. CONCLUSIONS AND CLINICAL RELEVANCE: Haemodynamic performance was improved by vatinoxan co-administration with medetomidine-butorphanol, before and after ketamine administration. However, vatinoxan was associated with mild hypotension after ketamine with the dose used in this study. Vatinoxan shortened the duration of anaesthesia.

Matrine ameliorates cognitive deficits via inhibition of microglia mediated neuroinflammation in an Alzheimer's disease mouse model.

Amyloid ß (Aß) induced microglial activation and attendant neuroinflammation play pivotal roles in Alzheimer's disease (AD) pathogenesis. Matrine is a natural anti-inflammation compound from the Chinese herbal medicine Sophora flavescens Ait. (Kushen). This study aimed to investigate the effects of matrine on memory deficit and neuroinflammation in an oligomeric Aß (oAß)-induced AD mice model. Whether microglial activation and NADPH oxidase were involved in these effects were further studied. Different doses of matrine (10, 20, or 40 mg/kg) were intragastrically administered once a day after intracerebroventricular oAß injection (2.5 µg/µl, 4 µl). 15 days after the oAß injection, behavioral experiments including novel object recognition (NOR) test and Morris water maze (MWM) test were performed. 21 days after the oAß injection, concentration of ROS, TNF-α, IL-1ß and IL-6 as well as expression of NADPH oxidase subunits gp91phox and p47phox in mice hippocampal tissues were assessed, and microglial activation were evaluated by Iba-1 immunohistochemical staining. Results of NOR test and MWM test revealed that oAß injection could remarkably impair learning and memory function in AD mice, and matrine administration could significantly ameliorate the impairment. ROS, TNF-α, IL-1ß and IL-6 levels increased after oAß injection, while matrine could significantly reduce the concentrations of these inflammatory factors. OAß induced protein expression of NADPH oxidase subunits gp91phox and p47phox were also significantly reduced by matrine. Iba-1 immunohistochemistry results showed less activated microglia in matrine-treated mice brain. These results indicate that matrine could ameliorate learning and memory impairment and neuroinflammation induced by oAß injection. These effects were found to be mediated through inhibition of microglial activation and NADPH oxidase expression in hippocampal tissue. The results suggest that matrine may be a valuable natural compound with therapeutic potential against AD.

[Compound matrine injection reduces morphine tolerance of the mice with lung cancer by inhibiting expression of multidrug resistance gene 1 and P-glycoprotein].

Objective: To investigate the effect of compound matrine injection on morphine tolerance in mice with lung cancer in situ and the expressions of multidrug resistance gene 1 (MDR1) and P-glycoprotein (P-gp). Methods: A mouse model of lung cancer in situ and morphine tolerance mode was established. The mice were injected with gradient concentration of compound matrine. The pain thresholds under different conditions were measured by thermal radiation tail-flick method. The mRNA level of MDR1 was tested by reverse transcription polymerase chain reaction (RT-PCR) and the protein level of P-gp was detected by western blot. The DNA binding activity of cyclophosphoadenosine response element binding protein (CREB) to the promoter of MDR1 gene was detected by electrophoretic mobility shift assay (EMSA). Results: The maximum analgesic percentage (MPE) of the mice in the morphine group was (85.21±6.53)% on the 8th day, and decreased to (38.45±5.52)% and (28.14±4.52)% on the 10th and 12th day, respectively, which indicated the morphine tolerance of mice with lung cancer in situ.The MPE of the mice in the group treated with morphine and compound matrine injection (300 mg/kg) was (79.34±6.50)% on the 8th day, and decreased to (62.16±5.53)% and (40.20±4.50)% on the 10th and 12th day, respectively.The results of RT-PCR assay showed that the relative expression levels of MDR1 mRNA in the brain tissues of mice in the morphine group, saline group, morphine combined with compound matrine injection (300 mg/kg) group and compound matrine injection (200 mg/kg) group were 2.33±0.79, 1.04±0.38, 1.37±0.38, and 1.43±0.53, respectively. There were statistically significant differences between the morphine group and the normal saline group, the morphine group and the morphine combined with compound matrine injection (300 mg/kg) group (P<0.05). There was no significant difference between the normal saline group and the compound matrine injection (200 mg/kg) group (P=0.05). The results of western blot showed that the relative expression levels of P-gp protein in the brain tissue of mice in the morphine group, saline group, and morphine combined with compound matrine injection (300 mg/kg) group were 1.86±0.40, 1.00±0.23, and 1.27±0.27, respectively. The expression of P-gp protein in the morphine group was significantly higher than those of the normal saline group and the morphine combined with compound matrine injection (300 mg/kg) group (P<0.05). The DNA-binding activity of CREB in the saline group was (0.23±0.07) Pu, significantly lower than (0.89±0.23) Pu of morphine combined with naloxone group and (0.80±0.23) Pu of morphine group (P<0.05). While the CREB DNA binding activity of morphine combined with compound matrine injection (300 mg/kg) group was (0.79±0.21) Pu, implicated that compound matrine had marginal effect on the DNA-binding activity of CREB (P>0.05). Conclusion: Compound matrine injection can significantly improve morphine tolerance and drug resistance of lung cancer through inhibiting the upregulations of MDR1 and P-gp induced by morphine.

Oxymatrine ameliorates insulin resistance in rats with type 2 diabetes by regulating the expression of KSRP, PETN, and AKT in the liver.

Insulin resistance plays a key role in the development and progression of type 2 diabetes mellitus (T2DM). Recent studies found that insulin resistance was associated with the dysfunction of KH-type splicing regulatory protein (KSRP) expression and AKT pathway, and that oxymatrine possesses an antidiabetic effect. The aim of the present study was to investigate whether the protection of oxymatrine against T2DM was associated with the modulation of the KSRP expression and AKT pathway. Sprague-Dawley rats were fed a high-fat diet and injected with streptozotocin intraperitoneally to induce T2DM, which led to an increase in blood glucose levels and insulin resistance, and a decrease in insulin sensitivity and glycogen synthesis concomitant with KSRP downregulation, PTEN upregulation, and AKT phosphorylation deficiency. The administration of oxymatrine decreased blood glucose levels and insulin resistance, increased insulin sensitivity, and improved glycogen synthesis in the liver of T2DM rats, through a reversal in the expression of KSRP, PTEN, and AKT. On the basis of these observations, we concluded that oxymatrine can protect T2DM rats from insulin resistance through the regulation of the KSRP, PETN, and AKT expression in the liver.

Matrine suppresses lung metastasis of human hepatocellular carcinoma by directly targeting matrix metalloproteinase-9.

Matrine is a natural compound derived from Radix Sophora flavescens which is a commonly used Chinese herb. Herein, we report that matrine may inhibit lung metastasis in liver cancer in mice. Invasion chamber assay, scratch-wound assay and orthotopic liver tumor implantation mice were introduced to investigate the potential pharmacological effects of matrine on human hepatocellular carcinoma (HCC). Our results showed that matrine at non-toxic dose could significantly suppress PLC/PRF/5 and MHCC97L cells migration and invasion. Furthermore, matrine treatment (5 mg/kg/day) significantly decreased lung metastasis in orthotopic HCC mouse models. Quantitative polymerase chain reaction, gelatin zymography and immunoblotting assay indicated that matrine could inhibit the activity of matrix metalloproteinase-9 without down-regulating its protein expression in HCC. The docking approach, site-directed mutagenesis, and surface plasmon resonance were applied to identify residues involved in matrine binding in matrix metalloproteinase-9. The biophysical and cell-based assays showed that Pro415, Arg424 residue might contribute to the binding affinity of matrine on matrix metalloproteinase-9 activity. In conclusion, matrine might be a promising anti-cancer agent for inhibiting HCC metastasis.

Oxymatrine therapy inhibited epidermal cell proliferation and apoptosis in severe plaque psoriasis.

BACKGROUND: Psoriasis is a chronic skin disorder that manifests as epidermal keratinocyte hyperplasia. OBJECTIVES: We examined the effect of oxymatrine treatment on cell proliferation and apoptosis in skin lesions of psoriasis. PATIENTS AND METHODS: Patients with severe plaque psoriasis were treated with oxymatrine or with acitretin. The skin lesions were stained with proliferating cell nuclear antigen (PCNA), Ki-67 and Bcl-2, as well as examined by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labelling (TUNEL). We performed correlations of the Psoriasis Area and Severity Index (PASI) and the proliferation and apoptosis index. RESULTS: Oxymatrine significantly reduced the psoriasis lesions as demonstrated by the reduced PASI score after treatment [6·91; 95% confidence interval (CI) 5·00-8·81, P < 0·001]. In the oxymatrine group, the mitotic index was 26·15 (95% CI 24·80-27·49) before oxymatrine treatment, decreasing to 14·52 (95% CI 13·82-15·25; P < 0·001) after treatment, but remained higher than the normal group (6·24; 95% CI 5·87-6·61, P < 0·001). Oxymatrine also inhibited the proliferation of epidermal cells in the skin lesion as indicated by the reduced proliferation index after treatment (P < 0·01). In addition, oxymatrine treatment reduced cellular apoptosis as shown by increased Bcl-2 expression and a decrease in TUNEL-positive cells. The PASI score was positively correlated with mitotic index, proliferation index and apoptotic index (TUNEL), but negatively correlated with Bcl-2 expression. CONCLUSIONS: Oxymatrine treatment reduced proliferation but inhibited apoptosis of cells in the skin lesion. The balance between cell proliferation and turnover may contribute to the significant alleviation of psoriasis by oxymatrine. What's already known about this topic? Psoriasis manifests as epidermal keratinocyte hyperplasia with proliferation, keratinocyte maturation and turnover rates. Current drugs for psoriasis may inhibit cell proliferation but could not adjust the balance of cell division, differentiation and apoptosis. What does this study add? We studied the efficacy of oxymatrine in the treatment of psoriasis and analysed the correlation of skin lesions, proliferation and apoptosis index before and after oxymatrine treatment. What is the translational message? Our study has demonstrated that oxymatrine is effective in the treatment of severe plaque psoriasis. It has comparable efficacy with acitretin. Because acitretin treatment was sometimes associated with metabolic abnormalities, our study suggests oxymatrine therapy as an alternative treatment for psoriasis in the context of acitretin allergy or adverse reactions.

Matrine enhances the efficacy of adriamycin chemotherapy in osteosarcoma cells by the STAT3 pathway.

Matrine and adriamycin have been extensively considered to be effective in anticancer therapies. However, the role of matrine in the antitumor activity of adriamycin against human osteosarcoma (OS) remains elusive. The aim of this study was to investigate the effect of matrine in OS chemotherapy of adriamycin. In the study, we found that matrine promoted the inhibitory effect of adriamycin against OS cell proliferation and growth. Wound healing and transwell assays showed that the inhibitory effect of adriamycin against migration and invasion of OS cells was significantly enhanced by matrine. For the underlying mechanism investigation, we showed that adriamycin reduced the protein level of PCNA, MMP-9, phosphorylated STAT3, and survivin, which was further intensified by the application of matrine. These results show that matrine could promote the therapeutic efficacy of adriamycin against human OS.

Ascending single dose pharmacokinetics of cytisine in healthy adult smokers.

1. Cytisine, a partial agonist for the α4ß2-nAChR, is used as a smoking cessation medication. Cytisine's current dosing is complex and involves taking 1.5 mg several times a day. The aim of this study was to explore the effect of dose on the pharmacokinetics and safety of cytisine after a single dose in healthy adult smokers. 2. Participants were assigned to one of three groups (n = 6 in each group) to receive a single oral dose of 1.5, 3 or 4.5 mg of cytisine. Blood samples were collected up to 24 h post dose. Pulse, blood pressure and respiratory rate were measured. Adverse effects were recorded. 3. Cytisine reached peak plasma concentration 1-2 h post dose in all participants irrespective of dose, with no dose-dependent changes in the elimination phase. Mean (SD) cytisine exposure (AUC0-24h) were 81.9 (15.8), 181.9 (40.8) and 254.5 (48.1) ng.h/mL following 1.5, 3 and 4.5 mg, respectively. 4. Cytisine appears to have predictable pharmacokinetics following a single dose of up to 4.5 mg and may be safe given as a single 4.5 mg dose, which is threefold greater than the recommended dose taken at one time. This study is registered in ClinicalTrials.gov (ID:NCT02585024).

Effects of dexmedetomidine, with or without vatinoxan (MK-467), on minimum alveolar concentration of isoflurane in cats.

OBJECTIVE: To characterize the effects of dexmedetomidine, with or without vatinoxan, on the minimum alveolar concentration of isoflurane (MACISO) in cats. STUDY DESIGN: Randomized crossover experimental study. ANIMALS: A group of six adult healthy male neutered cats. METHODS: Cats were anesthetized with isoflurane in oxygen and instrumented. Dexmedetomidine was administered using a target-controlled infusion system to achieve 10 target plasma concentrations ranging from 0 to 40 ng mL-1. Additionally, vatinoxan or an equivalent volume of saline was administered using a target-controlled infusion system to achieve a target plasma concentration of 4 µg mL-1. Pulse rate (PR), respiratory rate, systolic arterial pressure (SAP), hemoglobin oxygen saturation, body temperature, end-tidal partial pressure of carbon dioxide and drug concentrations were measured. MACISO was determined at each target plasma dexmedetomidine concentration using the bracketing method and the tail clamp technique. Pharmacodynamic models were fitted to the plasma dexmedetomidine concentration-MACISO. Pharmacodynamic parameters were tested for equivalence, and if rejected, for difference. RESULTS: Dexmedetomidine alone decreased MACISO in a plasma concentration-dependent manner. Maximum reduction was 77 ± 4%; the dexmedetomidine concentration producing 50% of the maximum decrease (IC50) was 0.77 ng mL-1. Vatinoxan increased MACISO in the absence of dexmedetomidine, decreased the potency of dexmedetomidine for its MACISO-reducing effect (IC50 = 12 ng mL-1) and lessened the maximum MACISO reduction (60 ± 14%). PR decreased less and SAP increased less when dexmedetomidine was administered with vatinoxan compared with saline. CONCLUSION AND CLINICAL RELEVANCE: Vatinoxan altered the effect of dexmedetomidine on MACISO. A high plasma dexmedetomidine concentration in the presence of vatinoxan resulted in a large decrease in MACISO, with attenuation of dexmedetomidine-induced cardiovascular effects. The vatinoxan-dexmedetomidine combination may provide clinical benefits in isoflurane-anesthetized cats.

Cardiopulmonary effects of dexmedetomidine, with and without vatinoxan, in isoflurane-anesthetized cats.

OBJECTIVE: To characterize the cardiopulmonary effects of dexmedetomidine, with or without vatinoxan, in isoflurane-anesthetized cats. STUDY DESIGN: Randomized, crossover experimental study. ANIMALS: A group of six adult healthy male neutered cats. METHODS: Cats were instrumented during anesthesia with isoflurane in oxygen. Isoflurane end-tidal concentration was set to 1.25 minimum alveolar concentration (MAC). Dexmedetomidine was administered using a target-controlled infusion system to achieve and maintain 10 target plasma concentrations ranging from 0 to 40 ng mL-1. Furthermore, vatinoxan or an equivalent volume of saline was administered using a target-controlled infusion system to achieve and maintain a target plasma concentration of 4 µg mL-1. Isoflurane concentration was adjusted after each change in dexmedetomidine concentration to maintain a concentration equivalent to 1.25 MAC. Heart rate (HR), arterial blood pressure, central venous pressure (CVP), pulmonary artery pressure (PAP), pulmonary artery occlusion pressure (PAOP), body temperature, cardiac output, arterial and mixed-venous blood gas and pH and drug concentrations were measured. Additional variables were calculated from the measurements. RESULTS: Dexmedetomidine alone resulted in decreased HR, cardiac index, stroke index and oxygen delivery, and increased systolic, mean (MAP) and diastolic arterial pressure, CVP, PAP, PAOP, systemic vascular resistance index, rate-pressure product, left ventricular stroke work index and oxygen extraction ratio. Vatinoxan resulted in severe hypotension at target plasma dexmedetomidine concentrations <10 ng mL-1. Vatinoxan attenuated the cardiovascular effects of dexmedetomidine at the 10 and 20 ng mL-1 targets, but MAP could be maintained above 60 mmHg only when isoflurane concentration was <1.25 MAC. Less improvement in cardiovascular function was seen with vatinoxan at the 40 ng mL-1 target plasma dexmedetomidine concentration. CONCLUSIONS AND CLINICAL RELEVANCE: Vatinoxan, at the plasma concentration maintained in this study, attenuated the cardiovascular effects of dexmedetomidine in isoflurane-anesthetized cats. However, its administration resulted in hypotension, which may limit its clinical usefulness.

INTRAVENOUS VATINOXAN IN MARKHORS (CAPRA FALCONERI HEPTNERi) IMMOBILIZED WITH INTRAMUSCULAR MEDETOMIDINE AND KETAMINE-A PRELIMINARY DOSESCREENING STUDY.

Medetomidine is an α-2 adrenoceptor agonist commonly combined with ketamine for immobilization of nondomestic mammals. However, it may cause some remarkable adverse effects such as bradycardia, hypertension, and hypoxemia. Vatinoxan (previously called MK-467 and L-659,066) is an α-2 adrenoceptor antagonist that affects mostly the peripheral receptors due to its minimal ability to cross the blood-brain barrier. Therefore it alleviates the peripheral cardiovascular and pulmonary effects of medetomidine while sedation is maintained. In this study, the hypothesis was that vatinoxan would dose-dependently alleviate medetomidineinduced bradycardia, hypertension, and hypoxemia when administered intravenously (IV) after medetomidine and ketamine were administered intramuscularly (IM) to markhors (Capra falconeri heptneri), without impairing the immobilization. Various doses of vatinoxan were studied. In this prospective, randomized, assessor-blinded, clinical crossover study, eight markhors were immobilized two times (16 paired immobilizations altogether) with medetomidine (80 µg/kg) and ketamine (1.5 mg/kg), according to the estimated weight, IM in the same dart. Approximately 19 min later, vatinoxan (117-297 µg/kg) or saline placebo was injected IV. Atipamezole was used as a reversal agent. Pulse and respiratory rates, indirect blood pressures, arterial oxygen saturation, and body temperature were measured and blood samples collected. In general, vatinoxan alleviated the hypertension induced by medetomidine without affecting the quality of immobilization. The dose of vatinoxan correlated significantly with the reduction in arterial blood pressure. Vatinoxan showed potential to enhance cardiovascular function in captive nondomestic small ruminants immobilized with medetomidine-ketamine.

Plasma concentrations of cytisine, a commercially available plant-based alkaloid, in healthy adult smokers taking recommended doses for smoking cessation.

1. Cytisine is a plant alkaloid that is a partial agonist for the α4ß2 -nAChRs and is used as an aid to smoking cessation. To date, there are no published data on cytisine concentrations in humans following multiple dosing. The aim of this study was to determine cytisine plasma concentrations after taking recommended doses for smoking cessation and to report on adverse effects. 2. Subjects (n=10) were instructed to follow the 25-day standard dosing regimen of cytisine. Blood was collected at 0, 2, 4, 8 and 10 hours on day 1 then on subsequent visits (days 2, 3, 4, 6, 13, 14, 17, 18, 21, 22, 25 and 26) to measure plasma cytisine concentrations. Plasma concentrations were determined using a validated LC-MS method. 3. Accumulation of cytisine was observed with repeated dosing of cytisine on day 1. Mean ± SEM plasma cytisine concentration measured at 10 hours was 50.8 ± 4.7 ng/mL. Due to dose tapering, there was an overall decrease in plasma cytisine concentration over the whole treatment period. 4. Overall, cytisine was well-tolerated and adverse effects reported were minor, indicating that cytisine is safe at concentrations measured in this study. This study is registered in the Australia and New Zealand Clinical Trials Registry (ACTRN12613000002785).

Formulation and In Vitro Release Kinetics of Mucoadhesive Blend Gels Containing Matrine for Buccal Administration.

Enterovirus 71 (EV71) is a pathogenic factor of severe hand, foot, and mouth disease (HFMD). No vaccine or specific treatment is currently available for EV71 infection. Hence, we developed a buccal mucoadhesive gel containing matrine to protect against HFMD. Mucoadhesive gels were prepared by Carbopol 974P and were combined with Carbopol 971P, sodium carboxymethyl cellulose (CMC-Na), or hydroxypropylmethy cellulose (HPMC K100M). The formulations were characterized in terms of tensile testing and continuous flow techniques for mucoadhesion. The rheological studies and in vitro drug release characteristics were also investigated. The results showed that combinations of two polymers significantly improved mucoadhesion, especially Carbopol 974P blended with HPMC. Carbopol 974P to HPMC blend ratios of 1:1 and 2:1 induced better mucoadhesion in the tensile test and continuous flow method, respectively. The most sustained release was obtained at a Carbopol 974P to HPMC ratio of 2.5:1. A predominantly non-Fickian diffusion release mechanism was obtained. The gel containing 2.5% Carbopol 974P combined with 1% HPMC showed good mucoadhesion properties and sustained drug release.