Effects of SS320A, a new cysteine derivative, on the change in the number of goblet cells induced by isoproterenol in rat tracheal epithelium

Pharmacokinetics and Bioequivalence of Fudosteine in Healthy Chinese Volunteers Under Fasting and Fed Conditions: A 4-Way Replicate Crossover Study

The bioequivalence of a generic fudosteine tablet vs a brand-named fudosteine tablet under fasting and fed conditions was evaluated in this study. This randomized, open-label, single-dose, 4-way replicate, crossover, bioequivalence study included 64 healthy Chinese subjects (fasting cohort, n = 32; fed cohort, n = 32) who were assigned to receive a single 200-mg dose of generic or brand-named fudosteine. Blood samples were collected before dosing and up to 24 hours after dosing. The plasma concentrations of fudosteine were analyzed by high-performance liquid chromatography-tandem mass spectrometry. Safety was monitored. There were no significant differences in maximum plasma concentration (C_max ), area under the plasma concentration-time curve (AUC) from time 0 to time t (AUC_0-t ), or AUC from time 0 to infinity (AUC_0-∞ ) between the test and reference formulations. However, food showed a significant effect on C_max , AUC_0-t , and AUC_0-∞ for both generic and brand-named fudosteine. The 90%CIs of the test/reference ratios of C_max , AUC_0-t, and AUC_0-∞ were within the range of 80% to 125% under both fasting and fed conditions. No serious adverse events were reported. The bioequivalence between generic and brand-named fudosteine under fasting and fed conditions was demonstrated. Both of them had good tolerance for healthy Chinese volunteers. In addition, food delayed the absorption of fudosteine, so taking this medicine before meals might be an optimized option.

Antioxidants and Chronic Obstructive Pulmonary Disease

Antioxidants represent an attractive therapeutic avenue for individuals with chronic obstructive pulmonary disease (COPD). Cigarette smoke, the major cause of COPD, contains very high concentrations of gaseous and soluble oxidants that can directly induce cell injury and death. Furthermore, particulate matter in cigarette smoke activates lung macrophages that subsequently attract neutrophils. Both neutrophils and macrophages from the lungs of cigarette smokers continuously release large amounts of superoxide and hydrogen peroxide through the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase complex. Once individuals with COPD stop smoking, the neutrophilic inflammation in the airways and lung parenchyma persists, as do the markers of oxidative stress. Several animal models of cigarette smoke-induced injury have provided evidence that various antioxidants may prevent inflammation and morphological changes associated with COPD however, evidence of benefit in patients is less abundant. Although oxidants can inactivate alpha-1 antitrypsin and other protective proteins, damage lung tissue, and increase mucus production, they also are essential for killing pathogens and resolving inflammation. This review will examine the pre-clinical and clinical evidence of a role for antioxidants in the therapy of patients with COPD.

Effect of fudosteine, a cysteine derivative, on airway hyperresponsiveness, inflammation, and remodeling in a murine model of asthma

AIMS

Fudosteine is a cysteine derivative that is used as an expectorant in chronic bronchial inflammatory disorders. It has been shown to decrease the number of goblet cells in an animal model. This study examined the effects of fudosteine on airway inflammation and remodeling in a murine model of chronic asthma.

MAIN METHODS

BALB/c mice were sensitized by an intraperitoneal injection of ovalbumin (OVA), and subsequently challenged with nebulized ovalbumin three days a week for four weeks. Seventy-two hours after the fourth challenge, airway hyperresponsiveness (AHR) and the cell composition of bronchoalveolar lavage (BAL) fluid were assessed. Fudosteine was administered orally at 10mg/kg or 100mg/kg body weight from the first to the fourth challenge.

KEY FINDINGS

We investigated the effects of fudosteine on the development of allergic airway inflammation and airway hyperresponsiveness after chronic allergen challenges. The administration of fudosteine during the challenge with ovalbumin prevented the development of airway hyperresponsiveness and accumulation of lymphocytes in the airways. Eotaxin, IL-4, and TGF-β levels and the relative intensity of matrix metalloproteinase-2 and matrix metalloproteinase-9 (MMP-2 and MMP-9) in BAL fluid were reduced by the fudosteine treatment; however, the number of eosinophils in BAL fluid and serum IgE levels did not change. The expression of TGF-β, the development of goblet cell hyperplasia, subepithelial collagenization, and basement membrane thickening were also reduced by the fudosteine treatment.

SIGNIFICANCE

These results indicate that fudosteine is effective in reducing airway hyperresponsiveness, airway inflammation, and airway remodeling in a murine model of chronic asthma.

Fudosteine effects on mucin production

BACKGROUND

Many chronic respiratory conditions are associated with mucin hypersecretion induced by underlying inflammation.

OBJECTIVE

To analyse the results of a preclinical study assessing the pathogenic mechanisms of mucin hyperproduction and the consequent in vivo and in vitro effects of fudosteine, a mucoactive agent.

METHODS/RESULTS

Both LPS and TNF-alpha increased MUC5AC mucin production in vivo and in vitro, respectively, and fudosteine was found to reduce it by partially interfering with the kinase-mediated inflammation pathway that activates the MUC5AC gene.

CONCLUSIONS

Further preclinical testing in animal models with chronic airways inflammation is necessary.

The pharmacokinetics of orally administered fudosteine in healthy Chinese volunteers

The pharmacokinetics of fudosteine in healthy Chinese volunteers was investigated for the first time after single- and multiple-dose administration. Five male and five female volunteers were enrolled in this study. Each subject received 400 mg fudosteine capsules (the therapeutic dose) on day 1 after overnight fasting for the single-dose study and three times daily oral administration (400 mg) for 5 consecutive days until the sixth morning for the multiple-dose study. Serial blood samples were collected at specified time intervals up to 16 hours following the first and last doses of fudosteine. Plasma harvested from the blood was separated and analyzed for fudosteine levels by a validated high-performance liquid chromatography-electrospray ionization mass spectrometry (HPLC/ESI/MS) method employing percolumn derivatization with 9-fluorenylmethyl chloroformate (FMOC-Cl). Noncompartmental analysis was used for the calculation of the total area under the plasma concentration-time curve (AUC) from time zero to time infinity and the terminal half-life (t1/2) of fudosteine. The pharmacokinetic parameters for single- and multiple-dose administration were estimated as follows: Cmax amounted to 10.13+/-4.39 microg/mL and 11.75+/-6.51 microg/mL, tmax to 0.69+/-0.36 h and 0.53+/-0.12 h and t1/2 to 2.33+/-0.63 h and 2.40+/-0.37 h, respectively. No significant differences were found between single- and multiple-dose oral administration, although gender differences were observed.

Inhibition of endotoxin- and antigen-induced airway inflammation by fudosteine, a mucoactive agent

We evaluated the effect of a mucoactive agent (-)-(R)-2-amino-3-(3-hydroxypropylthio) propionic acid (fudosteine), on airway inflammation using endotoxin- and antigen-induced models. Time courses of growth related oncogene/cytokine-induced neutrophil chemoattractant-1 (GRO/CINC-1) production, neutrophil migration and goblet cell hyperplasia were examined in endotoxin-induced rat airway inflammation. GRO/CINC-1 in bronchoalveolar lavage fluid (BALF) increased in response to intratracheal instillation of endotoxin and peaked within 4 h. Neutrophils in BALF and goblet cells on trachea peaked 24 and 96 h after endotoxin instillation, respectively. Fudosteine significantly inhibited increases in GRO/CINC-1 at 10-100 mg/kg, and neutrophils and goblet cells at 30 and 100 mg/kg. These results suggest that inflammatory events including neutrophil chemoattractant production and neutrophil migration play important roles for goblet cell hyperplasia in endotoxin-induced airway inflammation, and fudosteine inhibits goblet cell hyperplasia by inhibiting GRO/CINC-1 production and/or neutrophil migration. Furthermore, fudosteine (100 mg/kg) inhibited ovalbumin-induced eosinophil infiltration into BALF, suggesting it attenuates asthmatic inflammation.

Effect of fudosteine, a cysteine derivative, on blood flow of tracheal microvasculature increased by airway inflammation

We examined the effect of fudosteine, a cysteine derivative, on blood flow of tracheal microvasculature increased by airway inflammation. Airway inflammation was elicited by sulfur dioxide (SO(2)) exposure for 2 weeks in rabbits. Each drug (500 mg/kg, p.o.) or 0.5% carboxymethylcellulose-Na (control group) was daily administered just before SO(2) exposure. After final SO(2) exposure was finished, blood flow of tracheal microvasculature was measured by blood perfusion monitor. Fudosteine or S-carboxymethylcysteine (S-CMC) significantly suppressed blood flow of tracheal microvasculature increased by SO(2) exposure. However, no effect of fudosteine was observed on the pharmacological microvascular response in trachea of SO(2)-exposed rabbits. On the other hand, fudosteine or S-CMC scavenged superoxide anion generated from rat neutrophils, and enzymatically generated from xanthine oxidase-acetaldehyde reaction. The results suggest that suppressive action in increased tracheal blood flow of fudosteine is due to anti-inflammatory activity, at least in part, via scavenging of superoxide anion.

Effect of fudosteine, a new cysteine derivative, on mucociliary transport

We examined the effect of fudosteine ((-)-(R)-2-amino-3-(3-hydroxypropylthio)propionic acid) on the mucociliary transport (MCT) rate in quails. The MCT rate was estimated by ash transport velocity on the tracheal mucosa of quails. Fudosteine (500 mg kg(-1), p.o.) did not affect the normal MCT rate. However, topical application of fudosteine to the tracheal mucosa dose-dependently protected the impairment of the MCT rate caused by exposure to cigarette smoke. The results suggest that fudosteine may participate in the defence mechanism in the respiratory tract against irritant gases.