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In this work, the acute and subchronic toxicities of desaminotyrosine (DAT) by oral administration in SD rats and its effects on the intestinal microflora were investigated. The acute toxicity test showed that DAT is a low-toxic substance with a LD 50 of 3129 mg/kg. The subchronic toxicity test showed that DAT has no toxicity at a low dose (125 mg/kg/day). However, DAT exhibited obvious toxicities to food intake, liver, kidney, and lung at higher dose (250 mg/kg/day and 500 mg/kg/day). DAT inhibited the food intake of rats in a dose-dependent manner. Serum biochemical analysis showed that DAT can increase the serum glucose level of rats. Fecal microbiota analysis showed that DAT treatment can significantly change the intestinal microflora of rats, the dose of 125 mg/kg/day has the most significant effect on the diversity of intestinal microbiota. In daily application, the side effects caused by DAT might be gastrointestinal irritation, weight loss, liver or kidney injury, and blood sugar elevation. Based on our study, the no-observed-adverse-effect level (NOAEL) of DAT is 125 mg/kg BW/day for rats., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Attributed to several side effects, especially on hepatic tissues and body weight, there is always an urge of innovation and upgrading in already existing medication being used in maintaining diabetic condition. Therefore, in the present work, forty-eight molecules derived from arylpropionic acid scaffold were synthesized and their evaluation against diabetes was carried out. The synthesis of these molecules attributed to excellent dock score displayed by all the structures performed against PPAR-γ receptor site. Subsequently, all the derivatives were primarily deduced for their antidiabetic potential by OGTT. The compounds that showed significant antidiabetic activity in OGT Test and also exhibited high dock scores were assessed further by in vitro PPAR transactivation assay to assure analogy between in vivo and in vitro studies. The antidiabetic activity of these active compounds was then evaluated on STZ induced diabetic model in vivo. The most active compounds were scrutinized for its effect on PPAR-γ gene expression and hepatotoxic effect. Finally, it was recapitulated that these derivatives can provide a new prospect towards the development of antidiabetic agents with fewer side effects., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Chlorogenic acid (CGA) decreases colon cancer-cell proliferation but the combined anti-cancer effects of CGA with its major colonic microbial metabolites, caffeic acid (CA), 3-phenylpropionic acid (3-PPA) and benzoic acid (BA), needs elucidation as they occur together in colonic digesta. Caco-2 cancer cells were treated for 24 h with the four compounds individually (50-1000 µM) and as an equimolar ratio (1:1:1:1; MIX). The effective concentration to decrease cell proliferation by 50% (EC 50 ) was lower for MIX (431 ± 51.84 µM) and CA (460 ± 21.88) versus CGA (758 ± 19.09 µM). The EC 50 for cytotoxicity measured by lactate dehydrogenase release in MIX (527 ± 75.34 µM) showed more potency than CA (740 ± 38.68 µM). Cell proliferation was decreased by 3-PPA and BA at 1000 µM with no cytotoxicity. Cell-cycle arrest was induced at the S-phase by CA (100 µM), MIX (100 µM), CGA (250 µM) and 3-PPA (500 µM) with activation of caspase-3 by CGA, CA, MIX (500 and 1000 µM). Mitochondrial DNA content was reduced by 3-PPA (1000 µM). The anti-cancer effects occurred at markedly lower concentrations of each compound within MIX than when provided singly, indicating that they function together to enhance anti-colon cancer activities., Competing Interests: The authors declare no conflict of interest.

In this work, an in situ gelling system composed of glycol chitosan (GC) was fabricated and evaluated regarding its tissue-adhesive, anti-bacterial and hemostatic properties. GC conjugated with 3-(4-hydroxyphenyl) propionic acid gelled immediately after illumination with blue light in the presence of ruthenium complex. The phenolic GC hydrogel was investigated regarding its mechanical property, hydration, degradation rate, cytotoxicity, tissue adhesiveness, and hemostatic ability. The hydrogel was shown to glue two pieces of tissues tightly in an egg-membrane model. The antibiotic-incorporated hydrogel killed bacteria effectively. When the hydrogel was applied to a wound in a mouse liver model, bleeding was reduced quickly and greatly. All the promising results show that the photo-chemically crosslinkable GC hydrogel could be used as a tissue adhesive, controlled drug release, and a hemostat., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

The significant contents of artepillin C (AC) in green propolis have prompted research on the biological activities of the compound. The present study evaluated the activity of this phenolic compound on DNA, assessing its genotoxic and antigenotoxic potentials in the somatic mutation and recombination test in Drosophila melanogaster. The standard (ST) and high-bioactivation (HB) crosses were used in the assessment of genotoxic potential, since they express cytochrome P450 metabolization enzymes differently. In the 0.1-1.6 mM concentration range, AC did not have any genotoxic action in either cross. Antigenotoxic potential was investigated using the ST cross. In co- and post-treatment protocols, AC 0.4, 0.8, and 1.6 mM did not modulate mutagenic action of ethyl methanesulphonate. However, though it did not influence the frequency of damage induced by mitomycin C in co-treatment, AC reduced genotoxicity of the mutagen when administered after damage, but only at 0.4 mM. This modulation is associated with the reduction of genetic damage caused by recombinational events. The results of the present study and literature findings indicate that the various responses elicited by AC, namely induction of DNA damage, production of genetic lesions, or activation of DNA repair mechanisms are functions of AC concentration., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

In recent years, human-induced pluripotent stem cell-derived cardiomyocytes (hiPS-CMs) have been widely used to develop evaluation systems for drug cardiotoxicity, including the arrhythmia caused by QT prolongation. To accurately assess the arrhythmogenic potential of drugs, associated with QT prolongation, we developed an evaluation system using hiPS-CMs and gene expression analysis. hiPS-CMs were treated with 8 arrhythmogenic and 17 non-arrhythmogenic drugs at several concentrations for 24 hr to comprehensively analyze gene expression. The results showed that 19 genes were upregulated in the arrhythmogenic drug-treated cells compared with their expression levels in the non-treated and non-arrhythmogenic drug-treated cells. The arrhythmogenic risks of the drugs were evaluated by scoring gene expression levels. The results indicated that arrhythmogenic risks could be inferred when cells were treated at a concentration 100 times higher than the maximum blood concentration of the drug. Thus, we succeeded in developing a system for evaluation of the arrhythmogenic potential of drugs using gene expression analysis.

Objectives: 2-Arylpropionic acid (profen) drugs are associated with severe hepatotoxicity; however, risk factors are still poorly understood. Acyl-coenzyme A (acyl-CoA) thioesters of profen drugs play a more important role in the covalent binding to rat hepatocyte proteins than the respective acyl-glucuronides. Therefore, we examined whether acyl-glucuronides, acyl-CoA thioesters and oxidative metabolites of profen drugs stereoselectively participated in liver damage., Methods: Cytotoxicity was determined by measuring lactate dehydrogenase (LDH) leakage from three-dimensional cultured rat hepatocytes., Key Findings: LDH leakage was not induced by R-2-phenylpropionic acid and R-ibuprofen greatly forming acyl-CoA thioesters. S-Naproxen metabolized mainly by Uridine 5'-diphosphate (UDP)-glucuronosyl-transferase did not enhance LDH leakage. However, flurbiprofen (FLP) induced LDH leakage. A selective cytochrome P450 (CYP) 2C11 inhibitor suppressed 40-50% of the R-FLP and S-FLP-induced cytotoxicity. Borneol non-stereoselectively accelerated the FLP-induced cytotoxicity. The R-FLP-induced cytotoxicity decreased intracellular adenosine triphosphate (ATP) levels to 50% of untreated hepatocytes. An inhibitor of mitochondrial permeability transition pore, cyclosporin A (Cys A), rescued ATP levels and LDH leakage back to control levels., Conclusion: The reactive acyl-CoA thioesters and acyl-glucuronides were not associated with liver damage, denying one of the leading hypotheses. CYP metabolism of FLP non-stereoselectively participated in Cys A-sensitive cytotoxicity, suggesting mitochondrial injury., (© 2015 Royal Pharmaceutical Society.)

Ethnopharmacological Relevance: Stahlianthus involucratus (Zingiberaceae) has long been used in traditional medicine to treat inflammation, pain, and fever. However, no pharmacological study of this plant has been reported to confirm these activities. The aim of this study was to investigate the anti-inflammatory, antinociceptive and antipyretic activities of Stahlianthus involucratus rhizome ethanol extract (SiE) in animal models., Materials and Methods: Anti-inflammatory activity of SiE was investigated in rats using ethyl phenylpropiolate (EPP)-induced ear edema, carrageenan- and arachidonic acid (AA)-induced hind paw edema, and cotton pellet-induced granuloma formation models. Acetic acid-induced writhing response in mice and tail-flick test in rats as well as yeast-induced hyperthermia in rats were used to investigate the antinociceptive and antipyretic activities, respectively., Results: SiE significantly inhibited EPP-induced ear edema, carrageenan- and AA-induced hind paw edema. Its inhibitory effect in carrageenan-induced hind paw edema seemed to be in a dose-dependent manner. In cotton pellet-induced granuloma formation, SiE showed suppressive effects on granuloma formation but not on body weight gain and dry thymus weight. It could normalize serum alkaline phosphatase activity to nearly normal level. SiE also possessed a significant inhibitory effect, which seemed to be dose-dependent, on acetic acid-induced writhing response, whereas only at the highest dose of SiE could significantly increase test reaction time at all time-points in tail-flick test. However, no antipyretic activity was observed., Conclusions: These results suggest that SiE possesses anti-inflammatory and antinociceptive, but not antipyretic, activities. This study therefore rationalizes the traditional use of SiE for the treatment of inflammation and pain., (Copyright © 2015. Published by Elsevier Ireland Ltd.)

Drug-induced liver injury has been observed in patients treated with the endothelin receptor antagonists sitaxentan and bosentan, but not following treatment with ambrisentan. The aim of our studies was to assess the possible role of multiple contributory mechanisms in this clinically relevant toxicity. Inhibition of the bile salt export pump (BSEP) and multidrug resistance-associated protein 2 was quantified using membrane vesicle assays. Inhibition of mitochondrial respiration in human liver-derived HuH-7 cells was determined using a Seahorse XF(e96) analyzer. Cytochrome P450 (P450)-independent and P450-mediated cell toxicity was assessed using transfected SV40-T-antigen-immortalized human liver epithelial (THLE) cell lines. Exposure-adjusted assay ratios were calculated by dividing the maximum human drug plasma concentrations by the IC50 or EC50 values obtained in vitro. Covalent binding (CVB) of radiolabeled drugs to human hepatocytes was quantified, and CVB body burdens were calculated by adjusting CVB values for fractional drug turnover in vitro and daily therapeutic dose. Sitaxentan exhibited positive exposure-adjusted signals in all five in vitro assays and a high CVB body burden. Bosentan exhibited a positive exposure-adjusted signal in one assay (BSEP inhibition) and a moderate CVB body burden. Ambrisentan exhibited no positive exposure-adjusted assay signals and a low CVB body burden. These data indicate that multiple mechanisms contribute to the rare, but potentially severe liver injury caused by sitaxentan in humans; provide a plausible rationale for the markedly lower propensity of bosentan to cause liver injury; and highlight the relative safety of ambrisentan., (Copyright © 2014 by The American Society for Pharmacology and Experimental Therapeutics.)

We reviewed the prophylactic effect of monosodium glutamate (MSG), a substance known as the "umami", on NSAID-induced small intestinal damage in rats. Loxoprofen, one of the NSAIDs frequently used in Asian countries, given orally at 60 mg/kg, caused hemorrhagic damage in the small intestine, mainly jejunum and ileum, concomitant with a down-regulation of Muc2 expression/ mucus secretion and an up-regulation of enterobacterial invasion and neutrophil migration as well as inducible nitric oxide synthase (iNOS) expression. The severity of these lesions was reduced by pretreatment with MSG (0.1~5%) given as a mixture of powder food (10 g/rat/day) for 5 days before administration of loxoprofen. The effect of MSG was accompanied by an up-regulation of Muc2 expression/ mucus secretion as well as a suppression of bacterial invasion, iNOS expression and myeloperoxidase activity. On the other hand, these lesions spontaneously healed within 7 days, but this process was hampered by loxoprofen at low doses (>10 mg/kg) given repeatedly for 5 days after ulceration. The healing-impairment effect of loxoprofen was accompanied by the down-regulation of vascular endothelium- derived growth factor (VEGF) expression and angiogenic response, and these responses were all antagonized by feeding diet containing 5% MSG for 5 days after ulceration. It is suggested that MSG exhibits a prophylactic effect against loxoprofen-induced small intestinal lesions, this effect is functionally associated with the up-regulation of Muc2 expression/mucus secretion, resulting in suppression of enterobacterial invasion and iNOS expression, the major pathogenic events in NSAID-induced enteropathy, and MSG also has the healing promoting effect on these lesions through enhancement of VEGF expression and angiogenesis.

We examined the effect of egualen, a stable azulene derivative, against gastric damage induced by ischemia/reperfusion (I/R), gastric bleeding induced by double antiplatelet therapy with aspirin (ASA) plus clopidogrel, and small intestinal damage generated by loxoprofen, and investigated the possible mechanisms involved in its protective action. Male C57BL/6 mice or SD rats were used under urethane anesthesia (gastric lesions) or in a conscious (intestinal lesions) state. I/R-induced gastric injury was produced in mice by clamping the celiac artery for 30 min, followed by reperfusion for 60 min. Gastric bleeding was induced in rats by luminal perfusion with 25 mM ASA+50 mM HCl for 2 hours in the presence of clopidogrel (30 mg/kg). To produce small intestinal lesions the rats were given loxoprofen (60 mg/kg) p.o. and killed 24 hours later. Egualen was given i.d. 60 min before I/R or ASA perfusion, while given p.o. twice 30 min before and 6 hours after loxoprofen. Egualen significantly prevented the I/R-induced gastric damage, and the effect was equivalent to that of seratrodast (TXA2 antagonist). This agent also significantly suppressed gastric bleeding induced by ASA plus clopidogrel, similar to PGE2. Likewise, egualen significantly prevented loxoprofen-induced damage in the small intestine, accompanied by an increase in the secretion of mucus and suppression of bacterial invasion as well as iNOS expression. These results suggest that egualen has a prophylactic effect against various lesions in the gastrointestinal mucosa, probably through its characteristic pharmacological properties, such as TXA2 antagonistic action, local mucosal protection, and stimulation of mucus secretion.

Hepatitis C virus (HCV) infection represents a serious health-care problem. Previously we reported the identification of NA255 from our natural products library using a HCV sub-genomic replicon cell culture system. Herein, we report how the absolute stereochemistry of NA255 was determined and an enantioselective synthetic method for NA255 derivatives was developed. The structure-activity relationship of the NA255 derivatives and rat pharmacokinetic profiles of the representative compounds are disclosed., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

A toxicologic and dermatologic review of benzyl propionate when used as a fragrance ingredient is presented. Benzyl propionate is a member of the fragrance structural group Aryl Alkyl Alcohol Simple Acid Esters (AAASAE). The AAASAE fragrance ingredients are prepared by reacting an aryl alkyl alcohol with a simple carboxylic acid (a chain of 1 to 4 carbons) to generate formate, acetate, propionate, butyrate, isobutyrate and carbonate esters. This review contains a detailed summary of all available toxicology and dermatology papers that are related to this individual fragrance ingredient and is not intended as a stand-alone document. Available data for benzyl propionate were evaluated, then summarized, and includes: physical properties, acute toxicity, skin irritation, skin sensitization, elicitation, toxicokinetics, and genotoxicity data. A safety assessment of the entire AAASAE will be published simultaneously with this document. Please refer to Belsito et al. (2012) for an overall assessment of the safe use of this material and all AAASAE in fragrances., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

We reviewed the effect of monosodium glutamate (MSG) on the development and healing of nonsteroidal anti-inflammatory drug (NSAID)-induced small intestinal lesions in rats. Loxoprofen (60 mg/kg, p.o.) induced lesions in the small intestine within 24 h, accompanied by a decrease of Muc2 expression and an increase in enterobacterial invasion and inducible nitric oxide synthase (iNOS) expression. These lesions were prevented when MSG was given as a mixture of powdered food for 5 days before the loxoprofen treatment. This effect of MSG was accompanied by an increase in Muc2 expression / mucus secretion as well as the suppression of bacterial invasion and iNOS expression. These intestinal lesions healed spontaneously within 6 days, but the process was impaired by the repeated administration of low-dose loxoprofen (30 mg/kg) for 5 days after the ulceration, with the decrease of vascular endothelial derived growth factor (VEGF) expression and angiogenesis. The healing-impairing effect of loxoprofen was prevented by feeding 5% MSG for 5 days after the ulceration. These results suggest that MSG not only prevents loxoprofen-induced small intestinal damage but also promotes a healing of these lesions; the former is functionally associated with the increase in Muc2 expression / mucus secretion and the suppression of bacterial invasion and iNOS expression, while the latter is associated with the stimulation of VEGF expression/angiogenesis.

Tesaglitazar was developed as a dual peroxisome proliferator-activated receptor (PPARα/γ). To support the clinical program, a hamster carcinogenicity study was performed. The only neoplastic findings possibly related to treatment with tesaglitazar were low incidences of hemangioma and hemangiosarcoma in the liver of male animals. A high-power, two-year investigative study with interim necropsies was performed to further elucidate these findings. Treatment with tesaglitazar resulted in changes typical for exaggerated PPARα pharmacology in rodents, such as hepatocellular hypertrophy and hepatocellular carcinoma, but not an increased frequency of hemangiosarcomas. At the highest dose level, there was an increased incidence of sinusoidal dilatation and hemangiomas. No increased endothelial cell (EC) proliferation was detected in vivo, which was confirmed by in vitro administration to ECs. Immunohistochemistry and gene expression analyses indicated increased cellular stress and vascular endothelial growth factor (VEGF) expression in the liver, which may have contributed to the sinusoidal dilatation. A two-fold increase in the level of circulating VEGF was detected in the hamster at all dose levels, whereas no effect on VEGF was observed in patients treated with tesaglitazar. In conclusion, investigations have demonstrated that tesaglitazar does not produce hemangiosarcomas in hamster despite a slight effect on vascular morphology in the liver.

Background: Modified steroidal derivatives (PK11-PK14) of p-bis(2-chloroethyl)aminophenyl propenate (PK15) were used to study their antitumour activity on Lewis lung carcinoma (LLC) and their effect on sister chromatid exchanges (SCEs) and human lymphocyte proliferation kinetics., Materials and Methods: LLC was tested in this study. C57BL mice were used for in vivo chemotherapy evaluation and the antitumour activity was assessed. Lymphocyte cultures were used to study the genotoxic effect in vitro., Results: PK15 and PK11 were the most effective against LLC, causing significant inhibition of tumour growth. PK11 and PK15 induced significant increase in SCE rates. A correlation was observed between the cytogenetic effect and the antitumour effectiveness., Conclusion: The order of the antitumour effectiveness of PK11-PK15 resembled the order of the cytogenetic damage induced by the same compounds in vitro.

Asthma, chronic obstructive pulmonary disease (COPD) and acute lung injury/acute respiratory distress syndrome (ALI/ARDS) are characterized by neutrophilic inflammation and elevated levels of leukotriene B4 (LTB4). However, the exact role of LTB4 pathways in mediating pulmonary neutrophilia and the potential therapeutic application of LTB4 receptor antagonists in these diseases remains controversial. Here we show that a novel dual BLT1 and BLT2 receptor antagonist, RO5101576, potently inhibited LTB4-evoked calcium mobilization in HL-60 cells and chemotaxis of human neutrophils. RO5101576 significantly attenuated LTB4-evoked pulmonary eosinophilia in guinea pigs. In non-human primates, RO5101576 inhibited allergen and ozone-evoked pulmonary neutrophilia, with comparable efficacy to budesonide (allergic responses). RO5101576 had no effects on LPS-evoked neutrophilia in guinea pigs and cigarette smoke-evoked neutrophilia in mice and rats. In toxicology studies RO5101576 was well-tolerated. Theses studies show differential effects of LTB4 receptor antagonism on neutrophil responses in vivo and suggest RO5101576 may represent a potential new treatment for pulmonary neutrophilia in asthma., (Copyright 2010 Elsevier Inc. All rights reserved.)

Chronic treatment with suprapharmacologic doses of peroxisome proliferator-activated receptor (PPAR) agonists has a known potential for causing left ventricular hypertrophy (LVH). The mechanism by which LVH develops is not well understood nor are biomarkers of it well characterized. Natriuretic peptides are important regulators of cardiac growth, blood volume, and arterial pressure and may be useful biomarkers of LVH and hemodynamic changes that precede it. We measured amino-terminal pro-atrial natriuretic peptide (NTproANP), amino-terminal pro-brain natriuretic peptide (NTproBNP), and cardiac troponin I (cTnI) concentrations in serum and plasma, as well as transcripts in left ventricular heart tissue for atrial natriuretic peptide precursor (Nppa), brain natriuretic peptide precursor (Nppb), and myosin heavy chain-beta (Myh7) as potential biomarkers of LVH induced by a PPARalpha/gamma dual agonist in Sprague-Dawley rats. We used magnetic resonance imaging, echocardiography, and hemodynamics to identify structural and functional cardiovascular changes related to the biomarkers. Heart-to-brain weight ratios (HW:BrW) were correlated with NTproANP, NTproBNP, and cTnI concentrations in serum as well as fold change in expression of Nppa and Nppb. LVH was characterized by increased left ventricular wall thickness and inner diameter, increased cardiac output, decreased arterial blood pressure, and increased heart rate. In these studies, each end point contributed to the early detection of LVH, the ability to monitor its progression, and demonstrated the ability of NTproANP concentration in serum to predict LVH and hemodynamic changes.

Background/aims: Patients treated with peroxisome proliferator-activated receptor analogs (PPAR) alpha or alpha/gamma may develop a transient and reversible increase in serum creatinine, the mechanism of which remains obscure. This study evaluates whether treatment with either PPAR-alpha or -alpha/gamma analogs, fenofibrate or tesaglitazar, may cause deterioration in renal hemodynamics or exert direct tubular or glomerular nephrotoxic effects in rats., Methods: Male Sprague-Dawley rats (300-320 g) were treated per os with fenofibrate (300 mg/kg/day), tesaglitazar (1.2 mg/kg/day) or vehicle, for 14 days. Glomerular filtration rate (GFR) and renal blood flow (RBF) were measured by inulin clearance and ultrasonic flowmetry, and cumulative excretion of sodium and creatinine were assessed. Biomarkers of glomerular and tubular injury were measured, including urinary albumin excretion and renal mRNA levels of kidney injury molecule 1 (Kim-1), lipocalin 2 (Lcn2), and osteopontin (Spp1)., Results: Fenofibrate and tesaglitazar improved the lipid profile, but caused no detectable decrease in GFR or RBF compared with vehicle-treated rats. Furthermore, the cumulative excretions of sodium and creatinine were not altered by the drugs. Finally, there was no significant difference between drug- and vehicle-treated groups in urinary albumin excretion or in the expression of renal injury biomarkers., Conclusions: In the rat, no direct nephrotoxic effect or deterioration in renal hemodynamics and function were observed following treatment with fenofibrate or tesaglitazar., (2010 S. Karger AG, Basel.)

A dynamic target-based pharmacophoric model mapping the CD4 binding site on HIV-1 gp120 was built and used to identify new hits able to inhibit gp120-CD4 protein-protein interactions. Two compounds showed micromolar inhibition of HIV-1 replication in cells attributable to an interference with the entry step of infection, by direct interaction with gp120. Inactivity of compounds toward a M475I strain suggested specific contacts with the Phe43 cavity of gp120.

The carcinogenic potential of naveglitazar, a gamma-dominant peroxisome proliferator-activated receptor (PPAR) alpha/gamma dual agonist, was evaluated in a two-year study in F344 rats (0, 0.3, 1.0, or 3.0 mg/kg, males; 0, 0.1, 0.3, or 1.0 mg/kg, females). Increased mortality in male rats of the high-dose group was related to cardiac-associated lesions, neoplasms, and undetermined causes. Degeneration and hypertrophy of the myocardium occurred with dose-responsive increased incidence and severity. Neoplasms with increased incidence included sarcomas in male rats and urinary bladder neoplasms in female rats. Most sarcomas in male rats occurred in the adipose tissue of the subcutis and were diagnosed as fibrosarcomas, with fewer liposarcomas and other histologic types. Non-neoplastic changes in adipose tissue included expansion of adipose tissue in multiple sites, alterations in cytoplasmic vesicular pattern in brown and white fat, increases in stroma and mesenchymal cells, and fibrosis. The severity of chronic progressive nephropathy was decreased in a dose-responsive manner in males, and hyperplasia and neoplasia of the mammary gland were decreased in incidence in females. The adverse effects of cardiotoxicity and increased incidence of neoplasms occurred with dose-responsive incidence and/or severity, and a no-effect level for these effects was not achieved in this study.

Ambrisentan is the second selective endothelin-A receptor antagonist to be licensed in Europe, and the first in the United States, for the management of pulmonary arterial hypertension (PAH). It has been shown to be clinically effective in improving exercise tolerance and functional class. Furthermore, ambrisentan is well tolerated and associated with low rates of liver toxicity and minimal interactions with other medicines commonly used to treat PAH. Overall, current data support a role for ambrisentan in the management of PAH. However, the results of longer-term follow-up studies are still required to fully assess efficacy and safety., (Copyright 2008 Prous Science, S.A.U. or its licensors. All rights reserved.)

Naveglitazar, a gamma-dominant peroxisome proliferator-activated receptor (PPAR) alpha/gamma dual agonist, was tested for carcinogenicity in F344 rats in a 2-year study. Changes in urine composition and urothelial morphology were characterized in a companion 18-month investigative study. A significant increase in neoplasms of the bladder occurred only in females of the high-dose group (14/60) in the carcinogenicity study. Trends toward increased cell proliferation in the urothelium were noted in both sexes at all time points evaluated in the 18-month study. Group means for urothelial mitogenesis were increased statistically significantly only in high-dose females at 12 and 18 months. Urothelial hyperplasia occurred in high-dose females at 18 months. Morphologic changes in the urothelium at earlier time points were limited to hypertrophy and decreased immunolabeling of the superficial cells for cytokeratin 20 (a marker of terminal differentiation in urothelial cells) in both males and females. No treatment-related changes in urinary parameters, including urinary sediments, were associated with the occurrence of urothelial proliferation. Urinary pH was unaffected by treatment in both males and females, but expected diurnal changes were demonstrated. Collectively, these data indicate that naveglitazar was associated with hypertrophic and proliferative effects on the urothelium, but a link with changes in urinary parameters was not demonstrated.

HEPP (D,L-3-hydroxy-3-ethyl-3-phenylpropionamide) is a novel anticonvulsant with promising anticonvulsant profile, which is being actively researched. The potential maternal and embryo/fetal toxicities of HEPP were evaluated in pregnant rats following subcutaneous (s.c.) administration during organogenesis (gestation days 6 through 14, GDs 6-14) and the fetal period (GDs 14-21). Single- and multiple-dose pharmacokinetics were also evaluated at the same periods in order to establish possible correlations with some maternal or embryo/fetal toxicity end points. Embryotoxicity was mainly indicated by a significant dose-concentration dependency in the increase in resorptions, high percentage of fully resorbed litters, and decrease in embryo body weights during the GD6-14 dosing period. No gross external alterations were observed in live fetuses. There was no indication of maternal toxicity; but a marked increase in maternal body weight was evident following dosing from GD14 to GD21. The maternal plasma profile following single subcutaneous dose of 50 mg/kg on both GD14 and GD21 showed a monoexponential elimination pattern. Statistically significant differences between treatments (GD14 versus GD21) were observed in elimination (k(el) = 0.12 versus 0.15 h(-1)), absorption (k(a) = 2.01 versus 3.14 h(-1)), maximum plasma concentration time points (T(max) = 1.49 versus 1.01 h); maximum plasma concentration (C(max) = 40.23 versus 36.31 microg/ml) and areas under the concentration-time curve (AUCs(0-infinity) = 421.88 versus 274 microg h/ml. Based on comparisons of C(max), T(max), and AUCs(0-infinity) between the actual data and single intraperitoneal (i.p.) data previously published, the s.c. administration exhibited slower disposition and higher absorbed amount. After multiple-dose administrations of 50 and 100 mg/kg every 12 h (07:00 and 19:00 h), steady-state plasma levels were lower than the computer prediction, and only slight accumulation was observed. In both dosing periods HEPP levels were similar in mothers and offspring at steady-state conditions. The high incidence of embryo death and reduced embryo weight at GD6-14 dosing compared to GD14-21 dosing suggest that embryos are more sensitive to the deleterious effects of HEPP than fetuses; however, the faster elimination observed at late gestation could also contribute to the lower toxicity observed during the fetal period. Because the maternal HEPP plasma levels and the AUC values were positively correlated with embryo/fetal toxicity end points, both pharmacokinetic parameters could be reliable indicators of offspring exposure and consequently of potential toxicity. These data suggest that the length of time that HEPP is present in the maternal plasma at a sufficiently high concentration could be determinant of adverse effects in the offspring.

To investigate the mechanism on photosensitive dermatitis caused by ketoprofen (KP) in humans, the following experiments were performed by topical application on guinea pigs. The phototoxicity study involving treatment with 10% solution of KP, its enantiomers (R-KP and S-KP), loxoprofen, and flurbiprofen revealed no phototoxic reactions. In the photoallergenicity study, KP and its enantiomers (0.5-2% solution) induced skin reaction at all dosages; however, loxoprofen and flurbiprofen (1-5% solution) did not induce such a photoallergenic reaction. These results suggest that the chemical structure of the benzophenone chromophore in KP would be one of the important factors for induction of the photoallergy since both loxoprofen and flurbiprofen do not possess this structure and hence lack photoallergenic potential. Furthermore, to assess time profiles of KP concentration in the skin and plasma, guinea pigs received a repeated topical application of R-KP and S-KP at a dosage of 40 mg/kg over a period of 3 days. Plasma KP concentrations were extremely low as compared to skin KP concentrations and were not detected at 72 h after the final dosing. At 24 h after the final dosing, KP concentrations in the skin with R-KP and S-KP treatment were 187.4 and 254.7 microg/g, respectively, and their half-lives were 80.5 and 84.4 h, respectively. KP concentrations at 336 h after final dosing were 11.3 microg/g for R-KP and 15.7 microg/g for S-KP treatment. The acylglycerol-combined KP concentrations at 336 h were 2% or less as compared to KP concentrations with R-KP and S-KP treatment. There were no differences in KP concentrations in the skin between R-KP and S-KP and in combined KP concentrations between the enantiomers. The present study indicates that photosensitive dermatitis after topical application of KP in humans, caused by photoallergenicity and not phototoxicity, can be reproduced in the animal testing, and suggests that the skin reaction may be caused by the long period of retention of KP in the skin.

The oral anti-inflammatory activity of 4,4'-dihydroxy-alpha-truxillic acid (1) was compared with that of two other nonsteroidal anti-inflammatory drugs, loxoprofen sodium (LOX) and diclofenac sodium (DIC). The activity of 1 against the inflammatory pain response induced by formalin was comparable to that of LOX, but weaker than that of DIC. In the monosodium urate (MSU)-induced acute inflammatory model, 1 showed stronger anti-inflammatory activity than both LOX and DIC. The ED50 value for 1 was 4.5 micromol/kg, while the values for LOX and DIC were 65 and 25 micromol/kg, respectively. Otherwise, the oral single-dose toxicity of 1 was investigated in both sexes of Sprague-Dawley rats administered once at a dose of 2000 mg/kg. 1 showed no death, clinical signs, changes in body weight or pathological findings related to the treatment. In addition, no mutagenicity was observed in the reverse mutation assay. Furthermore, 1 did not show any ulcerogenic activity at doses ranging from 30 to 300 mg/kg in rat. Thus, 1 might be considered to be an effective anti-inflammatory agent with no deleterious adverse effect.

Ultrasound-assisted synthesis of bioactive isoacoramone (1), a metabolite of Piper marginatum and Acorus tararinowii, has been achieved by oxidation of toxic beta-asarone (2) with potassium permanganate/copper sulphate/alumina into asaronaldehyde (3) followed by treatment with ethylmagnesium iodide to provide 1-(2,4,5-trimethoxy)phenyl-1-propanol (4) which upon further oxidation with potassium permanganate/copper sulphate afforded 1 in 64% yield (overall 32%). Toxicological evaluation of 1 reveals it to be nontoxic up to 60 mg/kg b.w.

The relationship between S- and N-alkylating reactivity and herbicidal activity within a series of chloroacetamides, including several commercial herbicides and newly synthesised analogues was studied. The S-alkylating reactivity of selected chloroacetamides, as well as those of atrazine and chlorfenprop-methyl, was determined by in vitro GSH conjugation at a ratio of GSH to alkylating agent of 25:1. A spectrophotometric reaction using 4-(4-nitrobenzyl)pyridine was used to characterise the N-alkylating reactivity of the chemicals. Our results indicate that a reduced level of N-alkylating reactivity correlates with an improved herbicidal efficacy at a practical rate. However, the phytoxicity of the molecules is not simply dependent on chemical reactivities, but strictly related to the molecular structure, indicating that lipophilicity, uptake, mobility and induction of detoxifying enzymes may also be decisive factors in the mode of action.

The combination therapy of a Kampo formula and an analgesic-antipyretic agent is often used for the common cold in Japan. We investigated the effect of such a combination therapy, using the Ephedra herb, which is a common ingredient of Kakkon-to and Mao-to, and Loxoprofen, a nonsteroidal anti-inflammatory drug (NSAID), on fever induced in an experimental model of mice under strong stress. The combination therapy of Ephedra herb and Loxoprofen caused gastric mucosal lesions and loss of body weight. It is considered that this combination therapy should be avoided because of its adverse effects.

Anti-inflammatory, analgesic and anti-pyretic effects of d-2-[4-(3-methyl-2-thienyl)phenyl]propionic acid (M-5011), a new non-steroidal anti-inflammatory drug (NSAID), were compared with those of indomethacin, diclofenac sodium and ketoprofen in rats and guinea pigs. Anti-inflammatory effect of M-5011 on ultraviolet-induced erythema in guinea pigs was 11.7 and 1.8 times more potent than that of indomethacin and ketoprofen, respectively. Inhibitory effect of M-5011 on carrageenin-induced paw edema was 2 and 1.5 times more potent than that of indomethacin and diclofenac sodium, respectively. Analgesic effect of M-5011 on dry yeast-induced hyperalgesia or adjuvant-induced arthritic pain was equipotent to that of indomethacin, diclofenac sodium or ketoprofen. Anti-pyretic effect of M-5011 on yeast-induced pyrexia in rats was 4.2 and 4.6 times more potent than that of indomethacin and ketoprofen, respectively. Inhibitory effect of M-5011 on prostaglandin E2 production in the exudate of air-pouch inflammation induced by carrageenin was 1.75 times more potent than that in the non-inflamed site (stomach). As a result, gastric ulcerogenic activity of M-5011 was half that of indomethacin in rat. These results suggest that M-5011 shows more potent anti-inflammatory and anti-pyretic effects and equipotent analgesic effect with low gastro-ulcerogenic activity compared with classical NSAIDs.

Artepillin C was extracted from Brazilian propolis. Artepillin C (3,5-diprenyl-4-hydroxycinnamic acid) has a molecular weight of 300.40 and possesses antibacterial activity. When artepillin C was applied to human and murine malignant tumor cells in vitro and in vivo, artepillin C exhibited a cytotoxic effect and the growth of tumor cells was clearly inhibited. The artepillin C was found to cause significant damage to solid tumor and leukemic cells by the MTT assay, DNA synthesis assay, and morphological observation in vitro. When xenografts of human tumor cells were transplanted into nude mice, the cytotoxic effects of artepillin C were most noticeable in carcinoma and malignant melanoma. Apoptosis, abortive mitosis, and massive necrosis combined were identified by histological observation after intratumor injection of 500 microg of artepillin C three times a week. In addition to suppression of tumor growth, there was an increase in the ratio of CD4/CD8 T cells, and in the total number of helper T cells. These findings indicate that artepillin C activates the immune system, and possesses direct antitumor activity.

A tumoricidal substance was isolated from Brazilian propolis as guided by cytotoxicity assay on HuH 13 (human hepatocellular carcinoma) cell and was characterized to be 3-[4-hydroxy-3,5-bis (3-methyl-2-butenyl) phenyl]-2-propenoic acid (3,5-diprenyl-4-hydroxycinnamic acid (artepillin C)). It exhibited preferential cytotoxicity to tumor cells cultured in vitro. The cytotoxicity observed seemed to be partly attributable to apoptosis-like DNA fragmentation. The compound showed anti-tumor activity more effective than that of 5-fluorouracil to transplantable human tumor cell lines when tested on histoculture drug response assay system.

Indometacin farnesil was compared with indomethacin and loxoprofen in rats to ascertain whether it caused less gastric mucosal damage than the two older drugs. Damage was evaluated in terms of the size of ulcers that formed after oral administration and the changes in concentrations of prostaglandins E2 and I2 in the mucosa. Indometacin farnesil caused less damage than indomethacin and tended to cause less damage than loxoprofen. Indometacin farnesil was less potent than indomethacin in inhibiting prostaglandin generation by gastric mucosa. This property of indometacin farnesil may contribute to the low ulcerogenicity of this compound.

1. NS-398 (N-[2-cyclohexyloxy-4-nitrophenyl] methanesulfonamide) is a new non-steroidal anti-inflammatory drug (NSAID) with analgesic and antipyretic effects. 2. The anti-inflammatory potency of NS-398 in rat carrageenin-induced edema was as potent as that of indomethacin and 8 times more potent than diclofenac. In rat adjuvant arthritis, NS-398 showed a therapeutic effect comparable to that seen with loxoprofen but less than that seen with indomethacin and diclofenac. 3. The analgesic potency of NS-398 in rat adjuvant arthritic pain was much the same as that of indomethacin, and was about 3-5 times higher than that of diclofenac and loxoprofen. In the Randall-Selitto method in rats, NS-398 was 2-7 times as potent as loxoprofen, diclofenac and indomethacin. In acetic acid-induced writhing in mice, NS-398 was equipotent to indomethacin and diclofenac. 4. In LPS-induced fever in rats, NS-398 was 1.5-4.5 times as potent as loxoprofen and indomethacin, but less potent than diclofenac. 5. NS-398 produced little gastric ulceration in doses of up to 1000 mg/kg, while reference drugs produced distinct stomach lesions in doses of 10-30 mg/kg. 6. NS-398 inhibited prostaglandin (PG) endoperoxide synthase from sheep seminal vesicle microsomes less potent than that of ibuprofen.

The carcinogenic potential of gamma-oryzanol, a drug mainly used for the treatment of hyperlipidaemia, was studied in F344 rats. Groups of 50 males and 50 females were fed a diet containing 0 (control), 200, 600 or 2000 mg gamma-oryzanol/kg body weight/day for 2 yr. Although females in the highest dose group (2000 mg/kg body weight) showed a slight decrease in body weight at 104 wk, there were no treatment-related changes in general condition, food consumption, mortality, organ weight or haematology. Histopathological examination showed various tumours in all groups, including the control group. In the control and 2000-mg/kg groups, high tumour incidences were observed in the testes, pituitary and thyroid of males, and in the pituitary, uterus and mammary gland of females; however, there was no significant increase in the incidence of any tumours between the control and the 2000-mg/kg groups. The findings indicate that under the experimental conditions described gamma-oryzanol was not carcinogenic in F344 rats.

The carcinogenic potential of gamma-oryzanol, a drug mainly used for the treatment of hyperlipidaemia, was studied in B6C3F1 mice. Groups of 50 males and 50 females were fed a diet containing 0 (control), 200, 600 or 2000 mg gamma-oryzanol/kg body weight/day for 78 wk. No treatment-related changes were observed in general condition, body weight, food consumption, mortality, organ weight or haematology. Histopathological examinations showed various tumours in all groups, including the control group. In the control and 2000-mg/kg groups, relatively high tumour incidences were observed in the liver of males and in the haematopoietic organs of females. However, there was no statistically significant difference in the incidence of any tumours between the control and the 2000-mg/kg groups. The findings indicate that under the experimental conditions described gamma-oryzanol was not carcinogenic in B6C3F1 mice.

As a part of short-term safety assessment of gamma-Oryzanol, the genotoxic or the carcinogenic initiation activity was studied in three genetic toxicity tests and the promotion activity was studied in a cell-cell communication inhibitory test. gamma-Oryzanol showed the negative response in the bacterial DNA repair test (Rec-assay), the bacterial reverse mutation tests (Ames test) and the rat bone marrow chromosome aberration test. Also, gamma-Oryzanol showed the negative response in the metabolic cooperation inhibition test using Chinese hamster V79 cells.

Acute toxicity of Ketoprofen, a nonsteroidal antiinflammatory analgestic, was studied using rat weanlings. Ketoprofen was intrarectally administered in the form of a mixture with T10, a basic materials for suppositaries. The results obtained were as follows: LD50 of KP was estimated to be 434 mg/kg in male weanlings and 496 mg/kg in female weanlings. These values were about four times higher than those obtained from our previous study (Shimpo et al., 1981) using six-weeks old adult rats of both sexes. The fact indicated that rat weanlings were far tolerant to KP intrarectally administered than young adult rats. Intrarectal administration of KP at high doses, caused death between the second and the seventh day after administration. Gross and histopathological examinations revealed that dead weanlings carried perforative peritonitis with ulcers mainly in jejunum and ileum not in rectum. It was therefore suggested that the ulcer was produced in small intestine by entero-hepatic circulation of KP and finally mortal peritonitis occurred.

The non-steroidal anti-inflammatory analgesic alpha-[4-(1-oxo-2-iso-indolinyl)-phenyl]propionic acid (indoprofen) was given p.o. in gelatin capsules to six groups of six Rhesus monkeys (three males and three females/group) for 15 months. Group I (five males and five females) served as control and was given empty gelatin capsules. The following daily doses were used: Group 2--20 mg/kg b.i.d.; Group 3--40 mg/kg q.d.; Group 4--30 mg/kg b.i.d.; Group 5--60 mg/kg q.d.; Group 6--40 mg/kg b.i.d. and Group 7--80 mg/kg q.d. Except for some elevated blood urea nitrogen levels after 12 months in the animals of Group 7, no changes in clinical function test values, absolute and relative kidney weights or renal gross abnormalities were found. The renal papillae and pelves were normal and not affected in all monkeys. The microscopic examination revealed a focal chronic interestitial nephritis in some of the monkeys. In the survivors the incidence of this disease increased from one out of ten control animals to three out of five monkeys in Group 7 (80 mg/kg/d). However, this quantal, statistically significant difference became biologically irrelevant and no longer statistically significant when these microscopic changes were quantified. The most severe case was seen in the control animal and the least pronounced in monkeys having received 80 mg/kg/d. When these cases of interstitial nephritis were further evaluated using a multifactorial point sampling procedure, no significant quantitative changes in renal tissue components, indicative of analgesic-induced nephropathy, were detectable.

Sixteen men received 3904 mg of aspirin, 2400 mg of fenoprofen, or placebo daily for 1 week in a double blind and crossover trial. Fecal blood loss was measured by 51Cr labeled red cells; gastric and duodenal pathology were observed endoscopically. There was more (P less than 0.05) blood loss (4.96 ml) after aspirin than after fenoprofen (2.46 ml) or placebo (0.79 ml). By endoscopic examination, aspirin induced more (P less than 0.05) gastrointestinal pathology than fenoprofen or placebo, and there was a correlation of 0.70 between the two methods used in this study.

Anti-inflammatory activity of 2-[p-(2-imidazo[1,2-a]pyridyl) phenyl]propionic acid (Y-9213, miroprofen) was studied on various experimental models. Miroprofen was found to be as active as indomethacin against the exudative inflammation such as pleuritis in rats induced by Evans blue-carrageenin and the peritonitis in mice induced by acetic acid, and against the local Shwartzman reaction in rabbits. Miroprofen also inhibited the formation of edema induced by carrageenin or kaolin in rats' paws at lower doses. Against the proliferation of connective tissues, miroprofen showed the inhibitory action at higher doses. The ulcerogenic activity of miroprofen in rats was less potent than that of indomethacin, and as active as that of phenylbutazone. These findings indicate that miroprofen may be more effective in suppressing pain responses and acute inflammation accompanied with increased vascular permeability.