Imaging of Hydroxyl-Radical Generation Using Dynamic Nuclear Polarization-Magnetic Resonance Imaging and a Spin-Trapping Agent.

Reactive oxygen species (ROS) play an important role in cell metabolism, but they can cause oxidative damage to biomolecules. Among ROS, the hydroxyl radical (·OH) is one of the most reactive molecules in biological systems because of its high reaction rate constant. Therefore, imaging of ·OH could be useful for evaluation of the redox mechanism and diagnosis of oxidative diseases.

The antibodies against 5-bromo-2'-deoxyuridine specifically recognize trifluridine incorporated into DNA.

Trifluridine (FTD) is a key component of the novel oral antitumor drug TAS-102 (also named TFTD), which consists of FTD and a thymidine phosphorylase inhibitor. FTD is supposed to exert its cytotoxicity via massive misincorporation into DNA, but the underlying mechanism of FTD incorporation into DNA and its correlation with cytotoxicity are not fully understood. The present study shows that several antibodies against 5-bromo-2'-deoxyuridine (BrdU) specifically cross-react with FTD, either anchored to bovine serum albumin or incorporated into DNA.

Redox imaging of skeletal muscle using in vivo DNP-MRI and its application to an animal model of local inflammation.

Disorders of skeletal muscle are often associated with inflammation and alterations in redox status. A non-invasive technique that could localize and evaluate the severity of skeletal muscle inflammation based on its redox environment would be useful for disease identification and monitoring, and for the development of treatments; however, no such technique currently exists. We describe a method for redox imaging of skeletal muscle using dynamic nuclear polarization magnetic resonance imaging (DNP-MRI), and apply this method to an animal model of local inflammation.

Trifluridine Induces p53-Dependent Sustained G2 Phase Arrest with Its Massive Misincorporation into DNA and Few DNA Strand Breaks.

Trifluridine (FTD) is a key component of the novel oral antitumor drug TAS-102, which consists of FTD and a thymidine phosphorylase inhibitor. Like 5-fluoro-2'-deoxyuridine (FdUrd), a deoxynucleoside form of 5-fluorouracil metabolite, FTD is sequentially phosphorylated and not only inhibits thymidylate synthase activity, but is also incorporated into DNA. Although TAS-102 was effective for the treatment of refractory metastatic colorectal cancer in clinical trials, the mechanism of FTD-induced cytotoxicity is not completely understood.

Possible involvement of host defense mechanism in the suppression of rat acute reflux esophagitis by the particular histamine H2 receptor antagonist lafutidine.

Aims: Gastroesophageal reflux disease is considered to be caused primarily by gastric juice refluxed into the esophagus. Here, we investigated the possible involvement of host defense mechanisms in the development of acute reflux esophagitis using lafutidine, a histamine H(2) receptor antagonist (H(2)RA) with proven gastric mucosal protective effects.

Methods And Results: The ligation of both the pylorus and the forestomach of SD rats under anesthesia caused hemorrhagic lesions in the esophageal mucosa at 6 h.

Combination therapy using oral S-1 and targeted agents against human tumor xenografts in nude mice.

In this study, combination therapies using the oral fluoropyrimidine tegafur-gimeracil-oteracil (S-1) with several targeted agents or antibodies, were evaluated. First, the effects of tyrosine kinase inhibitors (erlotinib hydrochloride, sorafenib tosilate and sunitinib malate) against human non-small cell lung cancer (NSCLC), breast cancer and colorectal cancer were evaluated in vivo. The effects of the combination of S-1 and targeted antibodies (bevacizumab and cetuximab) against human colorectal cancers was also evaluated in vivo.

Modulation of Bladder Afferent Activity by Propiverine and its Active Metabolites (M-1 and M-2) in Rats.

Objectives: To evaluate the effects of propiverine and its active metabolites (M-1 and M-2) on bladder function through modulation of afferent activity in rats.

Methods: Cystometry was performed in urethane anesthetized female rats. We examined the effects of intravesical administration of propiverine, M-1 and M-2 on bladder overactivity induced by oxotremorine-M (Oxo-M; non-selective mAChR agonist).

Effects of propiverine hydrochloride, an anticholinergic agent, on urethral continence mechanisms and plasma catecholamine concentration in rats.

Introduction And Hypothesis: Anticholinergics are used to treat overactive bladder. Anticholinergic agents such as propiverine hydrochloride reportedly increase plasma catecholamine levels in rats. It is also known that active urethral closure mechanisms prevents stress urinary incontinence (SUI), which is enhanced by central and peripheral noradrenergic system activation.

Up-regulation of α1a and α1d-adrenoceptors in the prostate by administration of subtype selective α1-adrenoceptor antagonist tamsulosin in patients with benign prostatic hyperplasia.

Purpose: We examined the change in α(1)-adrenoceptor subtype expression in the prostate due to chronic tamsulosin administration in a benign prostatic hyperplasia rat model and in patients.

Materials And Methods: We measured α(1)-adrenoceptor subtype expression after tamsulosin administration in the prostate of the benign prostatic hyperplasia rat model using TaqMan® reverse transcriptase-polymerase chain reaction. We also measured expression before and after 12-week tamsulosin treatment in the prostate of patients with benign prostatic hyperplasia.

In vivo evidence for a significant role of folylpolyglutamate synthase in combined chemotherapy with oral fluoropyrimidine, UFT or S-1, and leucovorin.

Combined chemotherapy with 5-fluorouracil and leucovorin (LV) has been widely used for the treatment of patients with colorectal cancer. Given that LV effects are attributable to increased levels of reduced folate in cancer cells, we attempted here to show the in vivo role of folylpolyglutamate synthetase (FPGS), which stabilizes intracellular reduced folate, in the anticancer activities of oral fluoropyrimidines, UFT or S-1, combined with LV. To this end, HCT-15 human colon cancer cells were knocked down for FPGS expression by RNA interference.

Are antimuscarinic drugs effective against urinary frequency mediated by atropine-resistant contractions?

In the disease states of urinary frequency and urgency, atropine-resistant contractions are known to be involved, in addition to contractions mediated by cholinergic nerves. This study was undertaken to investigate the mechanism underlying the development of atropine-resistant contractions using the representative antimuscarinic drugs solifenacin and tolterodine and also propiverine that has Ca(2+) channel-antagonizing activity in addition to antimuscarinic activity. Rat models of urinary frequency were established by intravesical infusion of acetylcholine (ACh) (cholinergic nerve-mediated urinary frequency model), acetic acid (AcOH) [non-adrenergic non-cholinergic nerve (NANC)-mediated urinary frequency model], or CaCl(2) (atropine-resistant contractions-mediated urinary frequency model).

Lafutidine, a unique histamine H2-receptor antagonist, inhibits distention-induced gastric acid secretion through an H2 receptor-independent mechanism.

Gastric acid secretion during the daytime has been implicated in the pathogenesis of acid-related diseases. Although daytime acid secretion is mainly governed by the parasympathetic vagal nerve, clinical observations have been accumulated that the H(2)-receptor antagonist lafutidine may have a strong effect. Here, we examined the actions of H(2)-receptor antagonists in a rat model of gastric acid secretion induced by stomach distention, a major post-meal stimulus.

Effects of the new benzimidazole derivative TAS-203, an orally active phosphodiesterase 4 inhibitor, on airway inflammation in rats and emetic responses in ferrets.

TAS-203 (2-[3-(cyclopropylmethoxy)-4-methoxyphenyl]-5-(1H-1,2,4-triazol-1-yl)-1H-benzimidazole, CAS 223909-92-0) is a novel phosphodiesterase 4 (PDE4) inhibitor that has been found to have good anti-inflammatory effects and low emetogenic activity in vivo. In the present studies, the anti-inflammatory profile of TAS-203 was examined and compared with that of cilomilast (CAS 153259-65-5), the most advanced PDE4 inhibitor. TAS-203 inhibited the activity of purified human PDE4 with an IC50 value of 88 nM and also the recombinant PDE4 subtypes (4A, 4B, 4C and 4D) with respective IC50 values of 47, 35, 227 and 43 nM.

Effect of leucovorin on the antitumor efficacy of the 5-FU prodrug, tegafur-uracil, in human colorectal cancer xenografts with various expression levels of thymidylate synthase.

The combination of oral tegafur-uracil (UFT) with leucovorin (LV) is used to treat patients with stage II to III colon cancer based on the results of postoperative randomized studies in which UFT/LV treatment showed an equivalent efficacy to intravenous 5-FU plus LV therapy. However, whether the addition of LV to UFT can elevate the antitumor activity of UFT in colorectal tumors with high expression levels of thymidylate synthase (TS), which affects 5-FU efficacy, remains to be clarified. This study investigated the effect of LV on the antitumor activity of UFT and/or 5-FU prodrugs in low folate diet-fed nude mice using human colorectal cancer xenografts with various expression levels of TS.

Oral fluoropyrimidine may augment the efficacy of aromatase inhibitor via the down-regulation of estrogen receptor in estrogen-responsive breast cancer xenografts.

The present preclinical study was designed to evaluate a new combination therapy comprised of the aromatase inhibitor anastrozole (ANA) and the oral fluoropyrimidines, UFT and S-1 against the estrogen receptor (ER)-positive human breast cancer cell line MCF-7/Arom 14, which was stably transfected with the cDNA of human aromatase. MCF-7/Arom 14 cells showed a high aromatase activity and notably were able to grow in the presence of testosterone and estradiol (E(2)) in vitro. ANA and 5-fluorouracil (5-FU) inhibited cell growth at concentrations of 0.

Synergistic antitumor effect of S-1 and HER2-targeting agents in gastric cancer with HER2 amplification.

Amplification of human epidermal growth factor receptor 2 (HER2) has been detected in 20% to 30% of gastric cancers and is associated with a poor outcome. Combination therapies with HER2-targeting agents and cytotoxic agents are considered a potential therapeutic option for gastric cancer with HER2 amplification. We have now investigated the effects of combination treatment with the oral fluoropyrimidine S-1 and the HER2-targeting agents lapatinib or trastuzumab in gastric cancer cells with or without HER2 amplification.

Prostate growth inhibition by subtype-selective alpha(1)-adrenoceptor antagonist naftopidil in benign prostatic hyperplasia.

Background: Recently, alpha(1)-adrenoceptors (alpha(1)-ARs) have been reported to play a prominent role in the growth of a variety of cells; however, little is known about prostate growth and subtype-specific effects on cell proliferation. We examined the role of alpha(1d)-AR in prostate growth and the effect of subtype-selective alpha(1)-AR antagonist, naftopidil, which has relatively higher affinity for alpha(1d)-AR, on prostate growth in vitro and in vivo.

Methods: First, we examined the effect of naftopidil on the cell proliferation of PrEC, PrSC, and PrSMC using WST-1 assay.

Preclinical rationale for combined use of endocrine therapy and 5-fluorouracil but neither doxorubicin nor paclitaxel in the treatment of endocrine-responsive breast cancer.

Purpose: Our previous study indicated that concurrent administration of 4-OH-tamoxifen (TAM) and 5-fluorouracil (5-FU), but not doxorubicin (Dox), resulted in additive antitumor effects on endocrine-responsive breast cancer cells. We further clarified the effects of combined administration of endocrine therapy with chemotherapeutic agents in this study.

Methods: Concurrent treatment with 4-OH-TAM and paclitaxel (Ptx) was investigated in estrogen receptor (ER)-positive breast cancer cells.

Oral fluoropyrimidine S-1 combined with leucovorin is a promising therapy for colorectal cancer: Evidence from a xenograft model of folate-depleted mice.

The oral fluoropyrimidine S-1 has marked efficacy in treating metastatic colorectal cancer patients. In the present study, we explored the therapeutic potential of combined in vivo treatment in the human colon cancer cell lines COL-1, KM12C and KM20C with consecutive oral S-1 and leucovorin (LV) in 2-week therapeutic periods. This combination had increased anticancer activity compared to S-1 alone in the xenografts tested.

New histopathological experimental model for benign prostatic hyperplasia: stromal hyperplasia in rats.

Purpose: Histological observations of clinical benign prostatic hyperplasia specimens show that benign prostatic hyperplasia tissue is mainly composed of stromal components, smooth muscle and fibrous tissue, so-called stromal hyperplasia. However, little is understood regarding the pathogenesis of this stromal hyperplasia due to no suitable stromal hyperplasia model to elucidate the pathology of benign prostatic hyperplasia. We created a novel model of benign prostatic hyperplasia accompanied by clinically relevant stromal hyperplasia.

Beneficial effects of suplatast tosilate (IPD-1151T) in a rat cystitis model induced by intravesical hydrochloric acid.

Objective: To examine the effects of suplatast tosilate (IPD-1151T), a Th2 cytokine inhibitor recently recognized to improve the symptoms in patients with interstitial cystitis (IC), in a rat model of HCl-induced chronic cystitis, to elucidate the possible mechanisms by which the drug improves the symptoms of IC.

Materials And Methods: Chronic cystitis was induced by intravesical instillation of 0.2 mL of 0.

Presence and characterization of prostaglandin D2-related molecules in nasal mucosa of patients with allergic rhinitis.

Background: Prostaglandin D2 (PGD2) is the major prostanoid produced in the acute phase of allergic reactions. However, its pathophysiological role in addition to the pathway of production in allergic rhinitis remains unclear. We sought to determine the expression of synthases and receptors for PGD2 in human nasal mucosa.

Involvement of integrin-linked kinase in capillary/tube-like network formation of human vascular endothelial cells.

Angiogenesis is a complex process involving an ECM and vascular endothelial cells (EC), and is regulated by various angiogenic factors including VEGF. The ability to form a capillary/tube-like network is a specialized function of EC. Therefore, in vitro angiogenesis was assessed by a capillary/tube-like network formation assay.

Effects of a novel anti-hyperlipidemic agent, S-2E, on blood lipid levels in rats with fructose-induced hypertriglyceridemia.

Using rats with fructose-induced hypertriglyceridemia, an animal model of human hypertriglyceridemia, we investigated whether (+)-(S)-p-[1-(p-tert-butylphenyl)-2-oxo-4-pyrrolidinyl]-methoxybenzoic acid (S-2E), a novel anti-hyperlipidemic agent, reduced the elevated levels of triglyceride (TG) and non-high-density lipoprotein cholesterol (non-HDL-C), and then whether it elevated HDL-C levels. At doses of 3-30 mg/kg, S-2E reduced elevated TG levels and non-HDL-C levels simultaneously in a dose-dependent manner after a week. Furthermore, S-2E treatment at 10 mg/kg for 4 weeks showed similar effects, while the elongation of intervals between feeding periods led to further increases in these levels.