DA6034 promotes gastric epithelial cell migration and wound-healing through the mTOR pathway.

BACKGROUND AND AIM: 7-Carboxymethyloxy-3',4',5-trimethoxy flavone (DA6034), a synthetic derivative of eupatilin, has a protective effect on gastric mucosa against various ulcerogens, and is currently in the phase III clinical trial in the treatment of peptic ulcer disease. Cell migration and/or growth plays a role in the repair process of gastric ulcer, so this study investigated the effect of DA6034 on the movement and proliferation of gastric epithelial cells and its associated signaling pathway. METHODS: The migration of AGS or SNU484 human gastric epithelial cells was shown by scratch-induced wound healing and transwell assays, and the proliferation of the cells was assessed by FACS and proliferation assays. RESULTS: Treatment of DA6034 promoted the migration of gastric epithelial cells in a concentration-dependent manner. DA6034 treatment facilitated the phosphorylation of mTOR that led to an increase in the activity of S6K1, indicating its ability to activate mTOR and S6K1. Rapamycin aborted the wound-healing effect of DA6034, which supported the role of mTOR activation in the wound-healing process. In addition, DA6034 treatment increased PI3K-dependent Akt phosphorylation, which was necessary for the enhancement of cell migration. DA6034, however, did not stimulate the proliferation of gastric epithelial cells, being consistent with no activation of ERK1/2 by the agent. CONCLUSIONS: DA6034 has the ability to heal scratch wounds, which may result from an increase in gastric epithelial cell migration as mediated by PI3K-Akt-dependent activation of mTOR and S6K1. Our finding may be of help in understanding the molecular basis of the anti-ulcer effect of DA6034.

Chronic administration of udenafil, a selective phosphodiesterase type 5 inhibitor, promotes erectile function recovery in an animal model of bilateral cavernous nerve crush injury.

INTRODUCTION: Preservation of the cavernous nerves (CNs) during radical prostatectomy is crucial for the patient's erectile function. Despite advances in operative technique, the majority of men report compromised erectile function postprostatectomy or complete loss of potency due to CN trauma even with nerve-sparing modifications. AIM: This study was designed to investigate whether repeated dosing of udenafil, a phosphodiesterase type 5 inhibitor, helps to improve erectile function after CN injury. METHODS: Using the CN crush injury model, 8-week-old male Sprague Dawley rats were divided into the following groups; sham-operated group, bilateral CN crush injury exposed to either no udenafil (vehicle) or udenafil (5, 20 mg/kg) daily for two different durations (4 and 8 weeks, p.o.). MAIN OUTCOME MEASURES: At both time points, CN electrical stimulation was used to assess erectile function by measuring the intracavernous pressure. The expressions of hypoxia-inducible factor 1-alpha (HIF-1α), transforming growth factor-beta (TGF-ß1), nerve growth factor (NGF), endothelin B receptor (ET(B) ), endothelial nitric oxide synthase (eNOS), neuronal nitric oxide synthase (nNOS), and sonic hedgehog homolog (SHH) in penile tissue were examined. Immunohistochemical antibody staining was performed for NGF, eNOS, nNOS, CD31, and alpha-smooth muscle actin (α-SMA). Additionally, terminal deoxynucleotidyl transferase-mediated nick-end labeling assay was performed to quantify apoptosis and the tissue slides were stained for Masson's trichrome to assess the smooth muscle/collagen ratio. RESULTS: Udenafil improved erectile function in a dose- and time-dependent manner with the maximum erectile function recovery achieved by 20 mg/kg udenafil at an 8-week time point. CN injury increased the expression of HIF-1α, TGF-ß1, NGF, and ET(B) , however, decreased the expression of eNOS, nNOS, and SHH. Udenafil significantly suppressed these alterations. The results from the histological analyses show that udenafil markedly reduces apoptosis induced by CN injury and augments the smooth muscle/collagen ratio. CONCLUSIONS: CN injury induces significantly impaired erectile function and altered gene/protein expression. Chronic administration of udenafil preserves erectile function and has a beneficial role against the pathophysiological consequences of CN injury.

Udenafil enhances the recovery of erectile function and ameliorates the pathophysiological consequences of cavernous nerve resection.

INTRODUCTION: Radical prostatectomy is the treatment of choice for prostate cancer patients. Despite the introduction of nerve-sparing surgical techniques, its success is not entirely guaranteed and the majority of patients report compromised erectile function following surgical procedures. AIM: This study was performed to investigate the effect of repeated dosing of udenafil, a novel phosphodiesterase type 5 inhibitor, on penile hypoxia and fibrosis induced by bilateral cavernous nerve resection (BCNR) in rats. METHODS: Thirty male Sprague-Dawley rats (300-320 g) were used in this study. The animals were divided into three groups; group I consisted of sham-operated animals (N = 10), animals in group II underwent BCNR alone (N = 10), and animals in group III were orally treated with 10 mg/kg udenafil b.i.d. for 8 weeks following BCNR (N = 10). MAIN OUTCOME MEASURES: The expression of transforming growth factor-beta1, hypoxia-inducible factor-1 alpha, endothelial nitric oxide synthase, neuronal nitric oxide synthase, and endothelin B receptor in penile tissue was examined at gene level. Additionally, erectile function, measured by intracavernous pressure (ICP), and pathological changes in the corpus cavernosum were examined. RESULTS: While fibrosis, apoptosis, and the expression of TGF-beta1, HIF-1 alpha, and ET(B) were significantly increased, and the expression of eNOS and nNOS were significantly decreased in group II, compared with the sham-operated animals, repeated dosing of udenafil significantly ameliorated these changes. Erectile function was profoundly impaired in animals that underwent BCNR alone, and udenafil treatment significantly attenuated this impairment as measured by ICP. CONCLUSIONS: These results demonstrate that long-term administration of udenafil ameliorates penile hypoxia and fibrosis induced by cavernous nerve resection. This study also suggests the potential beneficial role of repeated dosing of udenafil in the recovery of erectile function in patients with neuronal erectile dysfunction.

Beneficial effects of the combination of amlodipine and losartan for lowering blood pressure in spontaneously hypertensive rats.

A combination of antihypertensive agents can better control blood pressure and reduce the number and severity of side effects than a monotherapy. Since both CCBs (calcium channel blockers) and ARBs (angiotensin II receptor type-1 blockers) are current and effective antihypertensive drugs, this study assessed the synergistic antihypertensive effects as well as the optimal combination ratio of these two drugs. Amlodipine (3 mg/kg) or losartan (30 mg/kg) alone or a combination of each drug at a ratio 1:10 and 1:20 was administered orally to spontaneously hypertensive rats (SHR). A four-week treatment of either 3 mg/kg amlodipine or 30 mg/kg losartan alone decreased the systolic blood pressure (SBP). However, their combination significantly lowered the SBP from the 3(rd) week, and there was a positive correlation between this reduction in blood pressure and the improvement in arterial endothelium-dependent relaxation. In addition, the combination therapy (1:20) decreased both the cardiac mass and left ventricular weight to a greater extent than with either amlodipine or losartan alone. The collagen content in the cardiac tissue was also significantly lower after the 4-week combination therapy (1:10). These results suggest that the combined use of amlodipine and losartan might be more effective in treating hypertension than a monotherapy.

Microarray analysis of gene expression profile in the corpus cavernosum of hypercholesterolemic rats after chronic treatment with PDE5 inhibitor.

Gene expression changes in the corpus cavernosum of hypercholesterolemic rats were not fully assessed, which were not previously known to be associated with hypercholesterolemia-related erectile dysfunction (ED). To provide molecular insight into pathophysiology of hypercholesterolemia-related ED and to investigate the effects of Udenafil, a phosphodiesterase type 5 (PDE5) inhibitor, on gene expression, we performed microarray gene expression analysis via gene discovery methods using GenoCheck platinum cDNA chip (Ansan, S. Korea). Sixteen male Sprague-Dawley rats were fed 2% cholesterol diet for 5 months. Half of them were orally treated with Udenafil (20 mg/kg/day) simultaneously. Eight age-matched rats fed normal diet were served as normal control. RNA was extracted from corpus cavernosum and microarray analysis was performed. Decreased erectile responses and hypercholesterolemia were observed in hypercholesterolemic control group. In microarray analysis, 122 candidate genes were noted to be altered based on the magnitude of expression changes, which includes 44 down-regulated and 78 up-regulated genes compared with the age-matched normal controls. These changes were, however, significantly attenuated by treatment with Udenafil. Out of the 78 up-regulated genes, 8 genes were significantly decreased by the chronic treatment with Udenafil. The altered genes were cytochrome oxidase biogenesis protein OXA1, skeletal muscle myosin heavy chain, lipophilin, fast skeletal muscle isoforms beta/alpha, myosin light chain 3, cytochrome c oxidase, adipocyte fatty acid binding protein and one EST gene. In contrast, among the 44 down-regulated genes, Kruppel-like factor 5 and cyclin D1 genes were increased after the Udenafil treatment. These results provide the molecular basis for understanding the pathogenesis of hypercholesterolemia-related ED and offer clues on determining the underlying action mechanism of a PDE5 inhibitor.

Increased susceptibility of ethanol-treated gastric mucosa to naproxen and its inhibition by DA-9601, an Artemisia asiatica extract.

AIM: To examine the effect of DA-9601, a new gastroprotective agent, on the vulnerability of ethanol-treated rat's stomach to naproxen (NAP). METHODS: Male Sprague-Dawley rats were pretreated with 1 mL of 50% ethanol twice a day for 5 d and then NAP (50 mg/kg) was administered. DA-9601 was administered 1 h before NAP. Four hours after NAP, the rats were killed to examine gross injury index (mm2), histologic change and to determine mucosal levels of malondialdehyde (MDA), prostaglandin E2 (PGE2), glutathione (GSH) and myeloperoxidase (MPO). RESULTS: Pretreatment of ethanol significantly increased NAP-induced gastric lesions, as well as an increase in MDA and MPO. On the contrary, mucosal PGE2 and GSH contents were decreased dramatically by ethanol pretreatment, which were aggravated by NAP. DA-9601 significantly reduced NAP-induced gastric injury grossly and microscopically, regardless of pretreatment with ethanol. DA-9601 preserved, or rather, increased mucosal PGE2 and GSH in NAP-treated rats (P<0.05), with reduction in mucosal MDA and MPO levels. CONCLUSION: These results suggest that repeated alcohol consumption renders gastric mucosa more susceptible to NSAIDs though, at least in part, reduction of endogenous cytoprotectants including PGE2 and GSH, and increase in MPO activation, and that DA-9601, a new gastroprotectant, can reduce the increased vulnerability of ethanol consumers to NSAIDs-induced gastric damage via the mechanism in which PGE2 and GSH are involved.

Therapeutic effect of DA-9601 on chronic reflux gastritis induced by sodium taurocholate in rats.

AIM: To investigate the therapeutic effects of DA-9601 on sodium taurocholate (TCA)-induced chronic reflux gastritis in SD rats. METHODS: In this study, we have investigated the therapeutic effects of DA-9601 on chronic erosive and atrophic gastritis induced by 6 mo of TCA administration (5 mmol/L in drinking water) in SD rats. RESULTS: Four weeks of DA-9601 administration (0.065%, 0.216% in rat chow), following the withdrawal of TCA treatment, resulted in a significant decrease in total length of erosions in rats in a dose-dependent manner. Furthermore, the indicators of atrophic gastritis, such as reduced mucosal thickness and reduction in the number of parietal cells, were improved by the administration of DA-9601 in a dose-related manner. DA-9601 also attenuated inflammatory cell infiltration and the proliferation of collagenous fiber in the gastric mucosa. The improvement in the reduction of the gastric mucus was observed in the rats receiving a high dose of DA-9601 (0.216%). The therapeutic effect of DA-9601 on experimental chronic erosive gastritis was superior to that of rebamipide (1.08% in rat chow). Biochemical analyses showed increased mucosal prostaglandin E2 and reduced glutathione levels by DA-9601 treatment. CONCLUSION: We suggest that DA-9601 is a promising agent for the treatment of chronic erosive and atrophic gastritis with an etiological factor of bile reflux. Increased mucosal prostaglandin E2 and reduced glutathione by DA-9601 treatment may be therapeutic mechanisms for chronic erosive and atrophic gastritis.

DA-9201 shows anti-asthmatic effects by suppressing NF-kappaB expression in an ovalbumin-induced mouse model of asthma.

Nuclear factor kappa B (NF-kappaB) regulates the expression of multiple cytokines, chemokines, and cell adhesion molecules that are involved in the pathogenesis of asthma. We investigated the anti-asthmatic effects and the mechanism of action of DA-9201, an extract of the black rice, in a mouse model of asthma. Mice immunized with ovalbumin (OVA) were administered with DA-9201 (30, 100 or 300 mg/kg) or dexamethasone (DEXA, 3 mg/kg) for 2 weeks and challenged with aerosolized OVA during the last 3 days. Anti-asthmatic effects were assessed by means of enhanced pauses, level of total IgE and Th2 cytokines in plasma or bronchoalveolar lavage fluid (BALF), the percentage of eosinophils in BALF, and histopathological examination. The expression of NF-kappaB in nuclear and cytoplasmic fraction and its DNA-binding activity in lung tissues were analyzed by means of Western blotting and electrophoretic gel mobility shift assay (EMSA), respectively. DA-9201 significantly reduced airway hyperresponsiveness (AHR), total IgE level in plasma and BALF, IL-4, IL-5, and IL-13 levels in BALF, and the percentage of eosinophils in BALF. Tissue inflammation was significantly improved by DA-9201 treatment. In addition, DA-9201 dramatically suppressed the expression of NF-kappaB and its DNA-binding activity. These results suggest that DA-9201 may be useful for the treatment of asthma and its efficacy is related to suppression of NF-kappaB pathway.

DA-9601 for erosive gastritis: results of a double-blind placebo-controlled phase III clinical trial.

AIM: To determine the efficacy and safety of DA-9601 on erosive gastritis versus cetraxate as a standard drug by gastrointestinal endoscopy. METHODS: Five hundred and twelve patients with erosive gastritis were divided into three groups. The groups received 180 mg or 360 mg of DA-9601, or 600 mg of cetraxate (Neuer) t.i.d. for 2 wk, respectively. Endoscopic observations were performed before and 2 wk after the treatment, and the cure and improvement rates were investigated. RESULTS: Of the 512 intention-to-treat (ITT) population, 457 patients comprised the per protocol (PP) analysis. Endoscopic cure rate was significantly higher in the DA-9601 group than in the cetraxate group in both the PP (56%, 58% vs 36%; DA-9601 180 mg, 360 mg and cetraxate, respectively) and ITT (52%, 51% vs 35%) populations. Two DA-9601 groups (180 and 360 mg) had significantly higher endoscopic improvement rates than the cetraxate group in both the PP (67%, 65% vs 46%) and ITT (63%, 58% vs 45%) populations. The percentage of symptom relief over the 2 wk was found not significantly different between groups. During the study, both DA-9601 and cetraxate produced no treatment-associated adverse events. CONCLUSION: From these results, it appears that DA-9601 has excellent efficacy on erosive gastritis. This study also confirms the safety profile of DA-9601.

Inhibitory effects of DA-9601 on ethanol-induced gastrohemorrhagic lesions and gastric xanthine oxidase activity in rats.

The exposure of gastric mucosa to ethanol produces pathological changes such as inflammatory process, hemorrhagic erosions, even acute ulcers. The gastric mucosal lesions accompanied by a significant decrease of gastric blood flow and increase of reactive oxygen species (ROS) implicate a role of xanthine oxidase in ethanol-induced gastric hemorrhagic erosions. DA-9601, a novel antipeptic formulation of extracts of Artemisia asiatica Nakai, was studied for its inhibitory effect on gastric xanthine oxidase activity and type conversion of the enzyme that has a profound role in free radical generation. Intubation of absolute ethanol (4 g/kg) significantly induced gastrohemorrhagic lesions and lipid peroxidation in the rat stomach. Oral administration of DA-9601 at 40 mg/kg body weight significantly reduced ethanol-induced gastric mucosal hemorrhagic lesions and lipid peroxidation, which was proportional to the inhibitory effect of DA-9601 on alcohol-induced xanthine oxidase-type conversion and enzyme activity. The results suggest that alcohol-induced gastric mucosal damage may be, in part, due to the increased activity of xanthine oxidase and type conversion rate of the enzyme and that the preventive effect of DA-9601 on gastrohemorrhagic lesions would result from its inhibitory action against xanthine oxidase and oxidative stress in alcohol-treated rats.

DA-8159, a potent cGMP phosphodiesterase inhibitor, attenuates monocrotaline-induced pulmonary hypertension in rats.

In this study, we evaluated the effects of oral administration of DA-8159, a selective phosphodiesterase-5 inhibitor, on the development of pulmonary hypertension (PH) induced by monocrotaline (MCT). Rats were administered either MCT (60 mg/kg) or saline. MCT-treated rats were divided into three groups and received orally administered vehicle, or 1 mg/kg or 5 mg/kg of DA-8159, twice a day for twenty-one days. The MCT group demonstrated increased right ventricular weights, medial wall thickening in the pulmonary arteries, myocardial fibrosis and the level of plasma cyclic guanosine monophosphate (cGMP), along with decreased body weight gains. However, DA-8159 markedly and dose-dependently reduced the development of right ventricular hypertrophy and medial wall thickening. DA-8159 also amplified the increase in plasma cGMP level and significantly increased the level of lung cGMP, compared with the MCT group. Although the body weight gain was still lower from the saline-treated control group, DA-8159 demonstrated a significant increase in body weight gains, in both 1 mg/kg and 5 mg/kg groups, when compared with the MCT group. In myocardial morphology, MCT-induced myocardial fibrosis was markedly prevented by DA-8159. These results suggest that DA-8159 may be a useful oral treatment option for PH.

Efffect of recombinant human FSH on ovulation, pregnancy and in vitro fertilization in androgen-sterilized mice.

The effect of a new rhFSH, PG-0801, on oocyte quality, ovulation and in vitro fertilization (IVF) was examined in androgen-sterilized mice. Experimental sterility was induced by a single subcutaneous injection of testosterone propionate (TP, 1 mg/head) into 5 day old female mice. Ovulation was generated in the 10 to 13-week old TP-injected mice by a subcutaneous rhFSH injection (1, 5 or 10 IU/head) followed 48 hours later by a second rhFSH injection (1, 5 or 10 IU/head). For comparison, a subcutaneous PMSG (5 IU/head) injection was used for folliculogenesis and a hCG (5 IU/head) injection was used for ovulation. These were administered using the same protocol. The eggs were harvested from the oviducts and counted 17 to 20 hours after the second injection. IVF was performed by adding sperms (2 x 10(5)/ml to 2 x 106/ ml) to determine the functional activity of the eggs, and the fertilization rate was measured. In addition, the pregnancy rate and fetal development were examined after 15-17 days of gestation. The number of oocytes recovered from the rhFSH/rhFSH group increased dose-dependently and was slightly higher than that of the PMSG/hCG group. The pregnancy rates of the group receiving 1, 5, and 10 IU of rhFSH/rhFSH were 50%, 66.7%, and 75%, respectively, which were significantly higher than that of the control (untreated) group (0%). The numbers of viable fetuses in the 1, 5, and 10 IU/head of the rhFSH/rhFSH group (8.0 +/- 1.50, 8.9 +/- 1.02, and 8.9 +/- 1.12 fetuses/dam, respectively) were comparable to that of the 5 IU/head PMSG/ hCG group (9.4 +/- 0.94). The mice receiving rhFSH/rhFSH and PMSG/hCG showed similar fertilization rates (around 65%) via the IVF procedure. These results demonstrate that a new rhFSH, PG-0801, may be useful for inducing ovulation in functionally infertile patients and for superovulation in ovulatory patients participating in assisted reproductive technology (ART) programs.

Protective effects of acetyl-L-carnitine on neurodegenarative changes in chronic cerebral ischemia models and learning-memory impairment in aged rats.

This study investigated the effects of acetyl-L-carnitine (ALC) in secondarily-induced cerebral chronic ischemia models using rats with permanent ligation of bilateral common carotid arteries (BCCL) and spontaneously hypertensive rats (SHR). Additionally, we used normal aged rats as a primary dementia model. Chronic ALC administration at 100 mg/kg (p.o.) for 4 weeks significantly attenuated neurodegenerative changes. In groups receiving 50 mg/kg or 100 mg/kg, ALC inhibited the active astrocyte increase in cerebral tissues of both BCCL and SHR models. In BCCL rats, ALC administration (50 mg/kg or 100 mg/kg, p.o.) resulted in significant promotion of glutathione levels in brain tissues. We also confirmed behavioral improvement after ALC treatment (100 mg/kg for 8 weeks, p.o.) on learning-memory function using aged rats (18 months old) in a passive avoidance task and preservation of CA1 pyramidal neurons was coincided on histopathological observation. In conclusion, chronic ALC administration may ameliorate cerebral ischemia progress after a cerebrovascular disorder as well as spontaneous ageing-related cerebral dysfunction via hippocampal protection.

Candidate molecule for premature ejaculation, DA-8031: in vivo and in vitro characterization of DA-8031.

OBJECTIVES: To evaluate the efficacy of DA-8031 against premature ejaculation, we performed in vitro and in vivo pharmacologic studies. METHODS: We used a monoamine transporter binding affinity assay, receptor binding affinity assay, monoamine reuptake inhibition assay, and serotonin uptake inhibition assay in platelets and chemically induced ejaculation models in rats. RESULTS: The present study reports on the pharmacologic profile of the putative antipremature ejaculation drug, DA-8031. DA-8031 exhibits high affinity and selectivity to the serotonin transporter (Ki value 1.94 nM for 5-hydroxytryptamine transporter, 22 020 nM for norepinephrine transporter, and 77 679 nM for dopamine transporter) and potency to inhibit serotonin reuptake into the rat brain synaptosome in vitro (half maximal inhibitory concentration 6.52 nM for 5-hydroxytryptamine, 30.2 µM for norepinephrine, and 136.9 µM for dopamine). In the platelet serotonin uptake study, DA-8031 exhibited significant inhibition at oral doses of 10 and 30 mg/kg in a dose-dependent manner. In the sexual response studies, after oral and intravenous administration of DA-8031, ejaculation was significantly inhibited in both para-chloroamphetamine- and meta-chlorophenylpiperazine-mediated ejaculation models in rats. CONCLUSIONS: The pharmacologic profiles observed in the present study suggest the potential for DA-8031 as a therapeutic agent useful in the treatment of premature ejaculation.

Effects of DA-6034 on aqueous tear fluid secretion and conjunctival goblet cell proliferation.

PURPOSE: This study was conducted to evaluate the effect of DA-6034, a potent secretagogue, on aqueous tear fluid secretion and its quality in normal rabbit. We also evaluated, in animal models of experimentally induced dry eye disease, its effectiveness over time to stimulate aqueous tear production by ocular ferning test and goblet cell proliferation. METHODS: Aqueous tear production, total protein levels, and glycoprotein levels in normal rabbits were evaluated after topical application of DA-6034 (0.3, 1, and 3%). Moreover, time course aqueous tear volume measurement and ocular ferning test in tear fluid were performed in dry eyes of rabbits that had been given 1% atropine sulfate, topically. Altogether, tear fluid production and conjunctival goblet cell numbers were measured in dry eyes of mice that had been given topical scopolamine. RESULTS: Topical application of DA-6034 (0.3, 1, and 3%) significantly increased (P < 0.05) aqueous tear production in a concentration-dependent manner in normal rabbits. There was no change in total protein levels while glycoprotein levels were significantly increased (P < 0.05) at 3% DA-6034. The increase in aqueous tear fluid was significant (P < 0.05) and lasted for 2 h post-instillation in dry eyes of rabbits that had been given 1% atropine sulfate; 10-day repeated instillation of the drug in this model resulted in large and homogeneous fern-like tear patterns. In a mouse model, DA-6034 given as a 3% eyedrop solution significantly increased (P < 0.05) tear fluid production and conjunctival goblet cell number. CONCLUSIONS: These results suggest that DA-6034 accelerates not only tear secretion but also mucin production and may be a potential therapeutic agent for the treatment of dry eye disease.

Effect of udenafil on portal venous pressure and hepatic fibrosis in rats. A novel therapeutic option for portal hypertension.

The purpose of this study was to investigate the therapeutic efficacy of udenafil (CAS 268203-93-6), a phosphodiesterase type 5 (PDE5) inhibitor, on bile duct ligation (BDL)-induced portal hypertension. Udenafil was given orally to rats at dose levels of 1, 5 or 25 mg/kg/day for 3 weeks in order to examine the chronic effect on portal venous pressure (PVP). Udenafil was also given orally to investigate the sequential change of PVP in BDL animals. The effect of udenafil on hepatic stellate cell activation and fibrotic change-related protein mRNA expression were examined. In a pharmacokinetic study, the pharmacokinetic parameters in sham-operated rats and BDL rats were compared. Three-week udenafil treatment decreased PVP by approximately 30% compared to the vehicle group. In a single oral administration study, the PVP of the udenafil treated group was lower than that of the control group throughout the experimental period. Compared to control, udenafil suppressed the expression of procollagen type I and alpha-smooth muscle actin mRNA. In the pharmacokinetic study, the AUC of udenafil in BDL rats was approximately 5 times higher than that in sham-operated rats. The results of this study suggest that udenafil has beneficial effects on portal hypertension and the effect may well be attributed to its anti-fibrogenic activity.

Effects of DA-6034, a flavonoid derivative, on mucin-like glycoprotein and ocular surface integrity in a rabbit model.

This study was designed to assess whether DA-6034 (7-carboxymethyloxy-3',4',5-trimethoxy flavone monohydrate), a new synthetic derivative of eupatilin, increases secretion of mucin-like glycoprotein and some mucins species in conjunctiva and cornea, and contributes to the preservation of ocular surface integrity. Human conjunctival and corneal epithelial cells were incubated with DA-6034 (1-250 microM). To investigate mucin secreting activity more directly, isolated rat conjunctival goblet cells were also used. Corneal protection was investigated using a desiccation-induced rabbit model of dry eye syndrome. It was found that DA-6034 increased mucin-like glycoprotein levels of both conjunctival and corneal epithelial cells at concentrations above 100 microM. Using human conjunctival epithelial cells, it was demonstrated that treatment with DA-6034 (200 microM) significantly increased production of some mucins species including MUC1, MUC2, MUC4, MUC5AC, MUC5B, and MUC16. DA-6034 also significantly increased MUC5AC production from conjunctival goblet cells isolated from rats. In the rabbit desiccation model, an ophthalmic suspension containing 3% DA-6034 significantly reduced corneal damage induced by desiccation. These results suggest that DA-6034 is a good candidate for treatment of dry eye through maintaining ocular surface integrity, which might be related to mucin secretion.

Gastroprotective effects of DA-6034, a new flavonoid derivative, in various gastric mucosal damage models.

This study evaluated the gastroprotective activity of DA-6034 against various ulcerogens including ethanol, aspirin, indomethacin, stress, and acetic acid. The basic mechanisms of DA-6034 as a defensive factor such as mucus secretion and endogenous prostaglandin E(2) synthesis were determined. Rats with gastric lesions induced by ethanol-HCl, aspirin, indomethacin, and stress that had been pretreated with DA-6034 orally showed a statistically significant decrease or decreasing tendency of the gastric lesion. In acetic acid-induced gastric lesions, repeated oral administration of DA-6034 exhibited a U-shape activity in ulcer healing, with the maximum and minimum inhibition being observed at 30 and 10 mg/kg/day, respectively. DA-6034 also increased the mucus content in the gel layer as well as endogenous prostaglandin E(2) synthesis. These results suggest that DA-6034 prevents gastric mucosal injury, and these gastroprotective activities appear to be due to the increase in the gastric defensive systems.

Effects of amlodipine orotate on hypertension-related complications in spontaneously hypertensive rats.

Hypertension is a common problem in elderly patients, which usually requires chronic therapy under various physiological conditions including low gastric acidity (hypo- or anacidity). This study investigated a new salt type of amlodipine (CAS 88150-42-9) on blood pressure and hypertension-related complications in stroke-prone spontaneously hypertensive rats (SHR-SP). Amlodipine orotate was prepared by reacting orotic acid and amlodipine to increase the dissolution rate at higher gastric pH conditions. Twelve-week-old SHR-SP were randomly divided into five groups to receive either amlodipine orotate or amlodipine besylate (CAS 111470-99-6) at the doses of 3 and 10 mg/kg/day orally for four weeks. The age-matched normotensive Wistar Kyoto rats (WKY) served as the normal positive control group. The systolic blood pressure was reduced in the amlodipine treated SHR-SP in a dose-dependent manner with a similar potency irrespective of the salt type. Both amlodipines also reduced the left ventricular hypertrophy at high doses and concentration-dependently inhibited the Ca2+ induced contraction with a similar potency. Furthermore, semi-quantitative analysis of a cerebral injury revealed that the two salts of amlodipine reduced the stroke-re-lated lesions to a similar degree. These results suggest that the amlodipine orotate is effective in terms of its effects on hypertension, cardiac hypertrophy and stroke-related cerebral damage in SHR-SP.

Efficacy of troxerutin on streptozotocin-induced rat model in the early stage of diabetic retinopathy.

The vascular changes associated with early diabetic retinopathy, which include the formation of microaneurysms and acellular capillaries, vessel dilation, vascular endothelial growth factor expression, were investigated experimentally in streptozotocin-induced diabetic rats treated with antioxidants: troxerutin (trihydroxy-ethylrutoside, CAS 7085-55-4), Vaccinium myrtillus, and calcium dobesilate (hydroquinone calcium sulfonate, CAS 20123-80-2). The development and progression of retinopathy was followed using fundus photography. After 3 months, the rats were sacrificed and half of the eyes were prepared for neovascularization analysis, and the other half were used for VEGF (vascular endothelial growth factor) analysis. The results from fundus photography and ADPase (adenosine diphosphatase) staining were quantified by the percentage area of the retinal vasculature using a commercial image analyzer. The VEGF protein in the retinal homogenates was assessed using an ELISA (enzyme linked immunosorbent assay) kit and VEGF-mRNA by RT-PCR (reverse transcription polymerase chain reaction). In the ADPase stain, the retinal vascular percent area increased significantly in the diabetic control. Neovascularization and aneurysms were observed in the diabetic control and were attenuated by 50 mg/kg troxerutin, but the retinal vascular percentage area was not significantly different from the diabetic control. The VEGF protein concentration was higher in diabetic rats than in the nondiabetic rats (21.5 +/- 2.1 vs 27.7 +/- 5.8 pg/mg, p < 0.05), and this increase was attenuated by 10 mg/kg troxerutin (24.5 +/- 3.8 pg/mg, p < 0.05) and prevented by 50 mg/kg troxerutin (19.5 +/- 2.2 pg/mg, p < 0.05). However, there were no significant differences between the groups. The VEGF-mRNA density showed a increasing tendency by 20% in the diabetic rats compared with the non-diabetic rats (1.0 +/- 0.1 vs 1.2 +/- 0.1 VEGF/beta-actin), and this increase was corrected by 10 mg/kg troxerutin (1.0 +/- 0.1 VEGF/beta-actin), 50 mg/kg troxerutin (0.9 +/- 0.1 VEGF/beta-actin) and Vaccinium myrtillus (1.1 +/- 0.1 VEGF/beta-actin). Oxidative stress might be involved in the upregulation of retinal VEGF during early diabetes, and it is likely that troxerutin has comparatively effective antioxidant properties. Therefore, troxerutin might be a useful treatment for attenuating diabetic retinopathy.