Self-Assembling Organogels Based on Pluronic and Lecithin for Sustained Release of Etodolac: In Vitro and In Vivo Correlation.

BACKGROUND: Etodolac, a member of non steroidal anti-inflammatory drugs (NSAIDs), has a poor aqueous solubility. Long term administration of etodolac causes severe gastrointestinal disturbances such as peptic ulcer and bleeding. These disturbances could be overcome by alternative routes such as a topical administration. METHOD: In the present study, pluronic lecithin organogels (PLOs) were prepared by simple mixing of pluronic solution with lecithin solution. Etodolac was loaded into the prepared gels or added during the gel formation. The physicochemical properties of the modified organogels were investigated by different analysis including visual inspection, pH determination, viscosity, spreadability and extrudability. Also, the in vitro release studies of etodolac in the presence of different penetration enhancers were carried out. The anti-inflammatory behavior of the prepared etodolac organogel was investigated using carrageenan induced paw edema test. RESULTS: The results indicated that the prepared organogels showed good physicochemical properties. The organogels, containing a combination of tween 80 and oleic acid as penetration enhancers, showed the highest percentage of drug release. CONCLUSION: All tested organogels showed a significant oedema inhibition compared with oral indomethacin ® and Voltaren® as a topical marketed anti-inflammatory drug. Moreover, the increase of drug concentration from 1% to 5% w/w is accompanied with a longer duration of action up to 12 hrs. Therefore, the formulated organogels are considered as a promising vehicle for controlled topical delivery of etodolac.

R-etodolac induces E-cadherin and suppresses colitis-related mouse colon tumorigenesis.

Colorectal cancer is one of the most serious complications of ulcerative colitis (UC), and the risk of UC-associated neoplasia increases as the region and duration of the disease increase. Selective cyclooxygenase (COX)-2 inhibitors effectively diminish carcinogenesis in a murine UC model. However, this may exacerbate colitis. The selective COX-2 inhibitor etodolac is marketed as a racemic mixture of the R- and S-enantiomers. The biochemical and pharmacological effects of etodolac are caused by the S-enantiomer, while the R-enantiomer lacks COX-inhibitory activity. In this study, we evaluated the effect of R-etodolac on colitis-related mouse colon tumorigenesis. The mice received 1,2-dimethlhydrazine (DMH), and then chronic colitis was induced by administration of two cycles of DSS (each cycle: 3% DSS for 7 days followed by distilled water for 14 days). The mice were sacrificed 28 days after the completion of both cycles. Mice were divided into the following groups: group A served as a disease control; group B received a low (2-mg/kg) dose of R-etodolac every 3 days during the entire period; group C received a high (10-mg/kg) dose of R-etodolac on the same schedule as group B; and group D served as a normal control. Administration of R-etodolac decreased the disease activity index during the DSS administration cycle. The mean number of tumors was 17.8, 15.2, 6.0, and 0 in groups A-D, respectively. In group C, R-etodolac significantly suppressed the occurrence of neoplasia (p<0.05). Although R-etodolac treatment did not affect COX-2 expression, it significantly enhanced expression of E-cadherin in both neoplastic lesions and background mucosa (i.e., lesion-free colon). Thus, administration of R-etodolac exerts a suppressive effect on the development of neoplasia in a murine model of DSS-induced colitis without exacerbation of the colitis. These results suggest that R-etodolac could be useful in the prevention of UC-associated neoplasia.

Transcription factor NF-κB inhibitors as single therapeutic agents or in combination with classical chemotherapeutic agents for the treatment of hematologic malignancies.

Nuclear factor-kappaB (NF-κB) upregulates the transcription of proteins that promote cell survival, stimulate growth, induce angiogenesis and reduce susceptibility to apoptosis. NF-κB signaling pathway is constitutively activated in myelodysplastic syndrome (MDS), acute myeloid leukemia (AML), acute lymphocytic leukemia (ALL), chronic myeloid leukemia (CML), chronic lymphocytic leukemia (CLL), lymphomas and in multiple myeloma (MM). Inactive NF-κB is bound in the cytoplasm to its inhibitor IκB, which masks its nuclear localisation signal. Two protein kinases with a high degree of sequence similarity, IKKα and IKKß, mediate phosphorylation of IκB proteins and represent a convergence point for most signal transduction pathways leading to NF-κB activation. The overexpression of NF-κB and its anti-apoptotic cytoprotective effect suggest that it might be a useful therapeutic target for the treatment of hematologic malignancies. Several drugs effective for the treatment of MM, including proteasome inhibitors, thalidomide, lenalidomide and arsenic trioxide, block NF-κB activation. New agents with NF-κB inhibitory activity enhance the anti-MM effects of conventional chemotherapeutic agents and reduce different side-effects. Triptolide (diterpenoid triepoxyde), a purified component of a traditional Chinese medicine, extracted from a shrub-like vine named Trypterygium wilfordii Hook F (TWHF) inhibits transcriptional activation of NF-κB and downregulates the expression of various NF-κB-regulated genes. Triptolide (10-80 ng/ml) induces apoptosis of MM cells and effectively inhibits cell growth of MM cells. NF-κB activation can be also inhibited by IKKß-selective inhibitors, PS-1145dihydrochloride, MLN120B (both Millennium Pharmaceuticals, Cambridge, MA) and BMS-345541 (Bristol-Myers Squibb, Princeton, NJ). LC-1, the dimethylamino-parthenolide (DMAPT) derivative demonstrated significant cytotoxicity to AML blasts targeting NF-κB.

Evidence-based review of clinical studies on pharmacology (non-anesthetic studies).

We have divided the analysis of pharmacology studies into studies on local anesthetics and studies on all other pharmacologic agents. This division reflects the large number of studies focusing on methods for obtaining effective anesthesia in patients and permits an independent focus on those clinical studies evaluating nonanesthetic drugs. In this section, we review that alternative class of agents, with an emphasis this year on clinical studies evaluating oral analgesics.

Chemoprevention of spontaneous development of hepatocellular carcinomas in fatty liver Shionogi mice by a cyclooxygenase-2 inhibitor.

Cyclooxygenase 2 (COX-2) and retinoid X receptor alpha (RXRalpha) are suggested to have roles in carcinogenesis. COX-2 inhibitors have been reported to suppress growth of hepatocellular carcinoma (HCC) cell lines in vitro. However, little is known about the preventive effect of these drugs on spontaneous hepatocarcinogenesis in vivo. Etodolac exists in a racemic mixture containing S- and R-etodolac. S-etodolac is responsible for COX-2 inhibitory activity and R-etodolac is related to the downregulation of RXRalpha. Here, the effect of etodolac on spontaneous development of HCC in fatty liver Shionogi mice is evaluated. Etodolac was administered at a low (2 mg/kg) or high (10 mg/kg) dose three times a week for 16 months starting at the age of 3 months. The development of HCC was suppressed slightly in the high-dose group, and suppressed markedly in the low-dose group, although the development of fatty liver was not inhibited in either group. Plasma prostaglandin E2 levels were also decreased significantly in the low-dose group, consistent with the suppression of HCC. The expression of RXRalpha and proliferating cell nuclear antigen in non-tumorous liver tissues was decreased significantly in both the low-dose and high-dose groups. These findings show that etodolac treatment at an optimum dose suppresses hepatocarcinogenesis in vivo, and may be useful for preventing the development of HCC in humans.

Combined administration of ethodolac, ascorbic acid and radiotherapy as adjuvant therapies in an extrathoracic desmoid tumor with gross postoperative residual disease; case report and review of the literature.

A 37-year-old man was admitted with an extrathoracic desmoid tumor invading the brachial plexus. Magnetic resonance imaging (MRI) of the thorax demonstrated a 20 x 9 x 14 cm mass in the supraclavicular fossa, axillary fossa and the right side of the chest. It invaded the brachial plexus and circumscribed the subclavian and axillary arteries concentrically. Biopsy revealed desmoid tumor which was resected subtotally with the brachial plexus. The gross residual mass was treated postoperatively with radiotherapy (60 Gy) which resulted in major regression of the mass. Following radiotherapy, ethodolac with ascorbic acid were administered. The tumor was clinically indiscernible 35 months post-radiotherapy. This case shows the high effectiveness of radiotherapy along with less toxic medical treatment modalities in instances where local control is hard to achieve with surgery and highlights the importance of using multidisciplinary treatments to maintain good functional results.

Anti-inflammatory, antinociceptive, and gastric effects of Hypericum perforatum in rats.

The pharmacological activity of Hypericum perforatum was assessed using models of inflammation, nociception, and gastric mucosal injury in rats. H. perforatum was given systemically as well as orally. When administered systemically, H. perforatum (50-300 mg/kg, s.c.) produced a dose-related and significant inhibition of the edematogenic response to s.p. injection of carrageenan. The percentages of maximal inhibition by the above doses were 53.7, 61.3, and 75.3%, respectively (compared to 90% after 50 mg/kg fluoxetine and 60.7% after 72 mg/kg etodolac). In tests of nociception, H. perforatum, administered orally, displayed antinociceptive activity in the tail electric stimulation and hot plate tests. The antinociceptive activity was observed with 25 mg/kg and a maximal increase in hot plate latency by 50% (compared to 73.2 and 77.8% increases by 5 or 10 mg/kg fluoxetine, respectively). In contrast, the acetic acid-induced (0.6%, i.p.) writhing was significantly reduced by fluoxetine or etodolac, but not H. perforatum. Also, the nociceptive response caused by i.p. injection of capsaicin (1.6 microg/paw) was unaffected by H. perforatum, but reduced by fluoxetine. Injection of H. perforatum (50, 125, or 250 mg/kg, s.c.) to pylorus-ligated rats, decreased gastric acid secretion, but increased indomethacin-induced gastric mucosal lesions dose dependently. These results demonstrate that H. perforatum exhibits antiedematogenic and antinociceptive properties, which may be of value for the management of inflammatory painful conditions. The agent, however, causes gastric irritation and may aggravate that of NSAIDs.

Anti-inflammatory effect and low ulcerogenic activity of etodolac, a cyclooxygenase-2 selective non-steroidal anti-inflammatory drug, on adjuvant-induced arthritis in rats.

Adjuvant arthritic rats are known to be more susceptible to gastric damage induced by non-steroidal anti-inflammatory drugs (NSAIDs) than are normal rats. We compared the relative gastric safety profile of etodolac with those of meloxicam, diclofenac sodium and indometacin in adjuvant arthritic rats and normal rats or mice. As a measure of the safety profiles of NSAIDs, we used the safety index, the ratio of the dose that elicits gastric mucosal lesions to the effective dose as an anti-inflammatory or analgesic compound. The anti-inflammatory or analgesic effects of NSAIDs were assessed by paw swelling in adjuvant arthritic rats, and either carrageenin-induced paw edema or brewer's yeast-induced hyperalgesia, as well as acetic acid-induced writhing, in normal rats or mice. In addition, we also investigated the effects of these NSAIDs on human COX-1 and COX-2 activity. Etodolac and other NSAIDs inhibited paw swelling and caused gastric mucosal lesions in adjuvant arthritic rats in a dose-dependent manner. Etodolac showed the highest UD(50) value and safety index among these NSAIDs in arthritic rats. In normal rats, etodolac also showed the highest UD(50) value and safety index, except when its effects were assessed by acetic acid-induced writhing. Etodolac and meloxicam showed selectivity for human COX-2 over COX-1. In contrast, diclofenac sodium and indometacin were selective for COX-1. These results suggest that etodolac, a COX-2 selective NSAID, has anti-inflammatory effects with a better safety profile for the stomach than do non-selective NSAIDs, including diclofenac sodium and indometacin, in adjuvant arthritic as well as normal rats.

A study of the comparative efficacy of three common analgesics in the control of pain after third molar surgery under local anaesthesia.

BACKGROUND: The aim of this study was to evaluate the comparative efficacy of three commonly used analgesics (Panadeine, Diflunisal and Etodolac) in the control of pain after third molar surgery under local anaesthesia. METHODS: A randomized control study. Outcome of primary efficacy was judged by overall assessment of the area under the curve of graphs for pain intensity, measured from serial visual analogue scales over a 24-hour period. Other measures of efficacy included the number (per cent) of patients who took 'additional' analgesics and the incidence of adverse effects occurring in each treatment group over the study period. RESULTS: The three drugs were effective in the control of post-operative pain (p<0.01). Variations in pain intensity and the use of additional medication between the treatment groups were observed over the study period. The Diflunisal group experienced less pain than the Panadeine or Etodolac group (p<0.01). Furthermore, a lesser number of those in the Diflunisal group used additional medication compared to the other two groups (p<0.01). The incidence of side effects from all three drugs was low. CONCLUSION: Diflunisal is superior in the control of pain following third molar surgery under local anaesthesia than either Panadeine or Etodolac, and has few side effects.

Effects of the combined oral administration of NSAIDs and dextromethorphan on behavioral symptoms indicative of arthritic pain in rats.

The effects of combined single oral treatments with non-steroidal anti-inflammatory drugs (NSAIDs) and the non-competitive N-methyl-D-aspartate (NMDA) receptor antagonist dextromethorphan (DM) on arthritic pain were examined in a rat model of adjuvant-induced arthritis. Although 12.5-100 mg/kg doses of DM alone produced no reliable effects, treatments with ibuprofen (IB, 50 and 100 mg/kg but not 12.5 or 25 mg/kg) produced mild analgesia in arthritic rats as determined using the Randall-Sellito test. IB showed a dose-response relationship which appeared to plateau at doses of 50 and 100 mg/kg. Adding 50 mg/kg DM to each IB dose resulted in significantly greater analgesic activity than IB alone at doses of 25, 50 and 100 mg/kg. A similar interaction between 50 mg/kg DM and 50 mg/kg IB occurred with respect to spontaneous pain behavior. Adding 25 mg/kg DM to 25 mg/kg IB likewise increased analgesia as measured by both the Randall-Sellito and spontaneous pain behavior tests (both P < 0.05). Five more NSAIDs were evaluated using the Randall-Sellito test, which included naproxen (NP), piroxicam (PIR), etodolac (ET), diclofenac (DC), and ketorolac (KE). For all six NSAIDS, the addition of 50 mg/kg DM reliably increased their analgesic potency, as indicated by reliable increases in previously effective NSAID doses (all six NSAIDs) as well as previously ineffective NSAID doses (IB, NP, DC, and PIR). These data demonstrate that DM greatly potentiates the analgesic activity of IB, DC, NP, PIR, ET, and KT and increases the peak effect over the NSAIDs alone. Similiar to DM's previously demonstrated enhancement of opioid analgesia in acute pain, the combination of DM and an NSAID may represent a novel analgesic approach to improved management of arthritic pain.

The economic consequences of NSAID-induced gastropathy: the French context.

The costs of treating gastroduodenal ulcers caused by nonsteroidal anti-inflammatory drugs (NSAIDs) are shown to increase the total cost of NSAID treatment to the Assurance-Maladie, the French national health insurance system. This increased cost is termed the iatrogenic cost factor, and is defined as the ratio of the shadow price of an NSAID to its reimbursed cost. The shadow price is calculated from estimates of the incidence of NSAID-induced gastropathies, the cost of the drug, and the hospital and ambulatory costs of treating the gastropathies. The resulting iatrogenic cost factors are estimated as 1.36 for naproxen, 1.48 for sulindac, 1.65 for diclofenac, 1.67 for piroxicam, 2.00 for ketoprofen, and 2.12 for etodolac.