NS-398, a novel non-steroidal anti-inflammatory drug with potent analgesic and antipyretic effects, which causes minimal stomach lesions

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.

Apoptosis and suppression of tumor growth by artepillin C extracted from Brazilian propolis

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.

Comparison of gastrointestinal effects of aspirin and fenoprofen. A double blind crossover study

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.

Multiple compound-related adverse properties contribute to liver injury caused by endothelin receptor antagonists

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.

Investigation of anti-inflammatory, antinociceptive and antipyretic activities of Stahlianthus involucratus rhizome ethanol extract

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.

Effects of LTB4 receptor antagonism on pulmonary inflammation in rodents and non-human primates

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.

DNA-damaging, mutagenic, clastogenic and cell-cell communication inhibitory properties of gamma-oryzanol

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.

A dynamic target-based pharmacophoric model mapping the CD4 binding site on HIV-1 gp120 to identify new inhibitors of gp120-CD4 protein-protein interactions

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.

Study on the mechanism of photosensitive dermatitis caused by ketoprofen in the guinea pig

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.

Comparative studies on the gastrointestinal lesions caused by several nonsteroidal anti-inflammatory agents in rats

The gastrointestinal toxicity of a single oral administration of five nonsteroidal anti-inflammatory agents (NSAIDs) to rats was compared, by a method using 51Cr-labeled red blood cells (RBC), and by macroscopic and microscopic examination. From the profile of gastrointestinal bleeding, the NSAIDs could be divided into a group consisting of aspirin (ASA), oxaprozin (OXP) and 2-[4-(3-methyl-2-butenyl)phenyl]propionic acid (TA), which caused only a transient increase in fecal blood loss based on a gastric lesion, and another group including indomethacin (IM) and ibuprofen (IP), which produced a biphasic increase in the blood loss. The initial phase was caused not only by a gastric lesion but also an intestinal lesion, and the secondary phase originated only in the intestinal lesion. The order of potency causing blood loss was IM much greater than IP greater than ASA much greater than TA greater than OXP. The safety ratio of OXP and TA was shown to be more favorable than that of the other three drugs.

Carcinogenicity study of gamma-oryzanol in F344 rats

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.

Suprofen-induced uricosuria. A potential mechanism for acute nephropathy and flank pain

Suprofen, a nonsteroidal anti-inflammatory drug, has been associated with the onset of acute flank pain, hematuria, and transient renal dysfunction after the ingestion of one or two doses, particularly in young males. Potential mechanisms of this nephropathy were evaluated in normal males following ingestion of suprofen (200 mg) on two occasions: the first with ad libitum fluid intake and the second during forced water diuresis. On the first study occasion, creatinine clearance, the fractional excretions of uric acid (FEUA) and sodium (FENa), the urinary concentration of undissociated uric acid, and the urinary excretions of prostaglandins and glomerular and tubular proteins were assessed. On the second occasion, inulin and PAH clearances and FEUA and FENa were determined. Within 90 min after suprofen administration, the FEUA increased from 8.8 +/- 2.6 to 35.5 +/- 9.6% (p less than 0.05). Urine became supersaturated for uric acid during ad libitum fluid intake. Glomerular filtration rate, renal plasma flow, and FENa decreased significantly, while prostaglandin and protein excretions did not change. The findings are consistent with acute uric acid nephropathy as a mechanism of suprofen-induced renal dysfunction.

Anti-inflammatory Activity of 4,4'-Dihydroxy-.ALPHA.-truxillic Acid

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.

Alkylating reactivity and herbicidal activity of chloroacetamides

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.

Carcinogenicity study of gamma-oryzanol in B6C3F1 mice

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.

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, in rats and guinea pigs

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.

Ultrasound-Assisted Conversion of Toxic β-Asarone into Nontoxic Bioactive Phenylpropanoid: Isoacoramone, A Metabolite ofPiper MarginatumandAcorus Tararinowii

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.

[Acute toxicity of ketoprofen intrarectally administered in rats, with special reference to histopathological changes (author's transl)]

Acute toxicity was studied on Ketoprofen, one of the non-steroidal antiinflammatory analgesics, using SPF rats. Ketoprofen was intrarectally administered in three forms such as pure powder (KP), KP suspension in CMC solution (KP-CMC) and a mixture of KP with powdered basic materials of capsule (KP-T10). The results obtained were as follows:1. LD50 values of terms of KP were 84 mg/kg in male rats and 122 mg/kg in female rats when KP-CMC was administered intrarectally, and 117 mg/kg in male and 92 mg/kg in female when KP-T10 was administered intrarectally., while peroral administration of KP-CMC showed LD50 values of 68 mg/kg in males and 78 mg/kg in females in terms of KP. 2. Major toxic signs of KP were ulceration on small intestines and peritonitis. Degeneration of hepathocytes and decrease in thymus lymphocytes were also observed. 3. Minimum lethal dose of KP-T10 was slightly higher than that of KP-CMC.

In silico designing, in vitro and in vivo evaluation of potential PPAR-γ agonists derived from aryl propionic acid scaffold

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.

Safety assessment of desaminotyrosine: Acute, subchronic oral toxicity, and its effects on intestinal microbiota in rats

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 LD50 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.

The combination therapy of Ephedra herb and Loxoprofen caused gastric lesions in mice

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.