Immunomodifying and neuroprotective effects of noscapine: Implications for multiple sclerosis, neurodegenerative, and psychiatric disorders.

Noscapine is a phthalide isoquinoline alkaloid with antitussive activity. Noscapine protects oligodendroglia from ischemic and chemical injury, binds to bitter taste receptors, antagonizes the bradykinin and histaminergic systems, which may be of benefit in treatment of multiple sclerosis. Noscapine normalizes axonal transport and exerts significant therapeutic efficacy in animal models of Parkinson's Disease and Amyotrophic Lateral Sclerosis. Noscapine exerts neuroprotective effects on oxygen- and glucose-deprived fetal cortical neuronal cells and reduces ischemic brain damage in neonatal rat pups. Pilot clinical studies indicated some beneficial effects of noscapine in stroke. Noscapine harbours anxiolytic activity and methyl-noscapine blocks small conductance SK channels, which is beneficial in alleviating anxiety and depression. Noscapine exerts anticholinesterase activity and acts inhibitory on the inflammatory transcription factor NF-κB, which may be harnessed in treatment of Alzheimer's Disease. With its blood-brain barrier traversing features and versatile actions, noscapine may be a promising agent in the armamentarium against neurodegenerative and psychiatric diseases.

Combination of electrochemistry with chemometrics to introduce an efficient analytical method for simultaneous quantification of five opium alkaloids in complex matrices.

For the first time, an analytical methodology based on differential pulse voltammetry (DPV) at a glassy carbon electrode (GCE) and integration of three efficient strategies including variable selection based on ant colony optimization (ACO), mathematical pre-processing selection by genetic algorithm (GA), and sample selection (SS) through a distance-based procedure to improve partial least squares-1 (PLS-1, ACO-GA-SS-PLS-1) multivariate calibration (MVC) for the simultaneous determination of five opium alkaloids including morphine (MOP), noscapine (NOP), thebaine (TEB), codeine (COD), and papaverine (PAP) was used and validated. The baselines of the DPV signals were modeled as a smooth curve, using P-splines, a combination of B-splines and a discrete roughness penalty. After subtraction of the baseline we got a signal with a two-component probability density. One component was for the peaks and it was approximated by a uniform distribution on the potential axis. The other component was for the observed noise around the baseline. Some sources of bi-linearity deviation for electrochemical data were discussed and analyzed. The lack of bi-linearity was tackled by potential shift correction using correlation optimized warping (COW) algorithm. The MVC model was developed as a quinternary calibration model in a blank human serum sample (drug-free) provided by a healthy volunteer to regard the presence of a strong matrix effect which may be caused by the possible interferents present in the serum, and it was validated and tested with two independent sets of analytes mixtures in the blank and actual human serum samples, respectively. Fortunately, the proposed methodology was successful in simultaneous determination of MOP, NOP, TEB, COD, and PAP in both blank and actual human serum samples and its results were satisfactory comparable to those obtained by applying the reference method based on high performance liquid chromatography-ultraviolet detection (HPLC-UV).

Formulation approaches to improving the delivery of an antiviral drug with activity against seasonal flu.

The main objective of the present study was to develop formulations of noscapine hydrochloride hydrate with enhanced solubility and bioavailability using co-solvent- and cyclodextrin-based approaches. Different combinations of co-solvents, which were selected on the basis of high-throughput solubility screening, were subjected to in vitro intestinal drug permeability studies conducted with Ussing chambers. Vitamin E tocopherol polyethylene glycol succinate and propylene glycol based co-solvent formulations provided the maximum permeability coefficient for the drug. Inclusion complexes of the drug were prepared using hydroxypropyl-ß-cyclodextrin and sulphobutylether cyclodextrins. Pharmacokinetic studies were carried out in male Sprague-Dawley rats for the selected formulations. The relative bioavailabilities of the drug with the co-solvent- and cyclodextrin-based formulations were found to be similar.

Simultaneous voltammetric determination of morphine and noscapine by adsorptive differential pulse stripping method and least-squares support vector machines.

An adsorptive differential pulse stripping method for the simultaneous determination of morphine and noscapine is proposed. The procedure involves an adsorptive accumulation of morphine and noscapine on a hanging mercury drop electrode (HMDE), followed by oxidation of adsorbed morphine and noscapine by voltammetric scan using differential pulse modulation. The optimum experimental conditions are: pH 10.0, accumulation potential of -100 mV versus Ag/AgCl, accumulation time of 150 s, scan rate of 40 mV s(-1) and pulse height of 100 mV. Morphine and noscapine peak currents were observed in same potential region at about +0.25 V. The simultaneous determination of morphine and noscapine by using voltammetry is a difficult problem in analytical chemistry, due to voltammogram interferences. The resolution of mixture of morphine and noscapine by the application of least-squares support vector machines (LS-SVM) was performed. The linear dynamic ranges were 0.01-3.10 and 0.015-2.75 microg mL(-1) and detection limits were 3 and 7 ng mL(-1) for morphine and noscapine, respectively. The capability of the method for the analysis of real samples was evaluated by the determination of morphine and noscapine in addict's human plasma with satisfactory results.

The significance of putative urinary markers of illicit heroin use after consumption of poppy seed products.

After consumption of poppy seeds various substances were detected in urine or blood samples using an immunoassay and a sophisticated liquid chromatographic-tandem mass spectrometric procedure. These compounds are widely considered to be putative markers of heroin (HER) abuse whereas acetylcodeine was regarded as a marker for illicit preparations ("street HER"). Besides positive urinary opiate immunoassay results during a 48 hours monitoring period, peak concentrations of morphine (MOR), codeine and their glucuronides appeared 4 to 8 hours after ingestion of poppy seeds, and concentrations of total MOR higher than 10 microg/mL were observed. Also, in serum samples taken up to 6 hours after consumption, MOR glucuronides were found. Free MOR was only detected in traces (1 to 3 ng/mL) within 2 hours of consumption. In addition, 3 of 6 onsite opiate sweat tests revealed positive results 6.5 hours after ingestion. Furthermore, it was demonstrated that neither noscapine (NOS) nor papaverine (PAP) was detectable in urine or blood samples after the consumption of poppy seeds containing up to 94 microg NOS and up to 3.3 mug PAP. NOS and PAP were rapidly metabolized, whereas desmethylpapaverine and, especially, its glucuronide were found in urine samples of poppy seed consumers even 48 hours after consumption. According to these results PAP metabolites should not be regarded as markers of illicit HER abuse. In conclusion, only acetylcodeine can be regarded as a specific marker but has the problem of a short half-life. Therefore, we suggest that NOS and PAP, but not their metabolites, might be used cautiously as additional markers of illicit HER abuse as they have not been detected after oral intake of poppy seeds in normal doses. But it must be kept in mind that in some cases poppy seeds with an unusually high content of these alkaloids could be available, and that these substances are also agents in some pharmaceuticals.

Simultaneous determination of methylephedrine and noscapine in human plasma by liquid chromatography-tandem mass spectrometry.

A selective and sensitive method has been developed and validated for simultaneous quantification of methylephedrine and noscapine in human plasma. Analytes were extracted from human plasma samples by liquid-liquid extraction, separated on a Diamonsil C18 column and detected by tandem mass spectrometer with an atmospheric pressure chemical ionization (APCI) interface. Diphenhydramine was used as the internal standard (I.S.). The method was found to be precise and accurate within the linear range 0.1-100 ng/ml for each analyte. The intra- and inter-day relative standard deviations (R.S.D.s) were below 5.2% for methylephedrine and 6.7% for noscapine. The inter-day relative error (RE) as determined from quality control samples (QCs) was less than 3.0% for each analyte. The assay was successfully employed in a pharmacokinetic study after an oral administration of a multicomponent formulation containing 20 mg DL-methylephedrine hydrochloride, 16 mg noscapine, 300 mg paracetamol and 1mg of chlorpheniramine maleate.

Determination of noscapine in human plasma using solid-phase extraction and high-performance liquid chromatography.

A simple, reliable high-performance liquid chromatographic (HPLC) method has been developed and validated for the determination of noscapine in human plasma. Noscapine and the internal standard, papaverine were quantitatively extracted from plasma onto disposable extraction columns by means of an automated off-line solid-phase extraction system and were separated onto a reversed-phase column. The method was found to be precise and accurate within the range 7.2-270 ng/ml. No endogenous compounds interfered with the assay.

Noscapine does not show aneugenic activity in mouse oocytes.

To clarify if noscapine has the ability to induce polyploidy in rodent germ cells in vivo, a cytogenetic study of mouse metaphase II oocytes was conducted after oral treatment with noscapine at the doses of 20, 120 and 400 mg/kg. Plasma concentrations of noscapine were measured by reversed-phase liquid chromatography and UV detection in three satellite groups of mice up to 8 h after administration of these doses. Thus, the relationship of the maximum plasma concentration and the area under the curve (AUC) with that of meiotic progression could be established. Although noscapine was tested at the maximum tolerated dose, no delay of meiotic progression or induction of chromosome malsegregation could be shown as no increase in the frequency of metaphase I-arrested, polyploid or hyperploid oocytes were found. At the highest dose only, noscapine affected the physiology of superovulation as shown by a significant decrease in the mean number of oocytes harvested per female. In view of the large span covered by the doses tested, corresponding to concentrations far above those detected in humans, and the similarity between the pharmacokinetics of noscapine in mouse and humans, it is unlikely that noscapine represents a genetic risk for humans at therapeutic dosages.

Serum protein binding of noscapine: influence of a reversible hydrolysis.

The binding of the antitussive drug noscapine to human serum, pure albumin and alpha 1-acid glycoprotein has been investigated by ultrafiltration and equilibrium dialysis, using radiolabelled noscapine. The binding in serum pooled from volunteers was 93 +/- 0.2% (at 100 ng mL-1). After incubation for 24 h the binding decreased to about 85% (ultrafiltration 87.0 +/- 1.0%; equilibrium dialysis 84.3 +/- 1.2%), because of the conversion of noscapine to noscapinic acid. Only unbound drug underwent this hydrolysis, and as noscapine is extensively bound in healthy volunteers, this elimination process is probably unimportant. The major binding protein of noscapine was albumin (K = 3060 M-1, n = 5.62), but the binding to alpha 1-acid glycoprotein was also substantial (K = 31,500 M-1, n = 1.73). The interindividual variation in binding was low and binding was linear at the concentrations observed after therapeutic doses (0-500 ng mL-1).

Determination of noscapine and its metabolites in plasma by coupled-column liquid chromatography.

Noscapine, narcotoline and cotarnine were quantified in deproteinized plasma samples by using a coupled-column liquid chromatographic system. The drug and the metabolites were first separated into two groups on a short polar precolumn (-CN) with an acidic mobile phase, containing a low content of acetonitrile. The metabolites were transferred to a hydrophobic analytical column (C18) and separated with a mobile phase containing a counter ion and a co-ion in an acidic buffer with an high acetonitrile content. Noscapine was transferred to another hydrophobic analytical column (C18) with a mobile phase containing a counter ion in an acidic buffer with an high acetonitrile content. Ultraviolet detection at 310 nm was used for all three compounds. The limits of quantitation were 9 ng/ml for noscapine, 13 ng/ml for cotarnine and 20 ng/ml for narcotoline. The within-day precisions were better than 6% (relative standard deviation), and the absolute recoveries were above 82%.

Excretion of noscapine in human breast milk.

The excretion of noscapine in human breast milk was studied in 8 lactating women given a single oral dose of 100 or 150 mg after a light breakfast. Serum and milk samples were collected for 24 h after drug intake. Although noscapine is a weak base, only a small amount was excreted in the milk. The median milk/serum ratio was 0.29, range 0.15-0.88. The noscapine dose received by a child during a 24 hour period, when the maternal dose is 50 mg t.i.d., was calculated to be 0.8 (0.4-1.9) micrograms/kg (median and range).

Determination of noscapine in plasma by liquid chromatography.

A liquid chromatographic method has been developed for the determination of noscapine in plasma. Noscapine and the internal standard, papaverine, were extracted into methylene chloride by column extraction. The separation was performed on a straight-phase liquid chromatographic system using a mobile phase of hexane--methanol--chloroform--diethylamine. A high detection selectivity was obtained by UV detection at 310 nm. The precision of the method was 3.8% (standard deviation) at a level of 89 ng/ml and 9.5% (standard deviation) at 5.9 ng/ml. The selectivity of the analytical method was evaluated by comparing analytical results after isolation of extracts of plasma samples on reversed- and straight-phase liquid chromatographic systems.