Immunologic effects of nonsteroidal anti-inflammatory drugs

Identifying therapeutic candidates for endometriosis through a transcriptomics-based drug repositioning approach

Existing medical treatments for endometriosis-related pain are often ineffective, underscoring the need for new therapeutic strategies. In this study, we applied a computational drug repurposing pipeline to stratified and unstratified disease signatures based on endometrial gene expression data to identify potential therapeutics from existing drugs, based on expression reversal. Of 3,131 unique genes differentially expressed by at least one of six endometriosis signatures, only 308 (9.8%) were in common; however, 221 out of 299 drugs identified, (73.9%) were shared. We selected fenoprofen, an uncommonly prescribed NSAID that was the top therapeutic candidate for further investigation. When testing fenoprofen in an established rat model of endometriosis, fenoprofen successfully alleviated endometriosis-associated vaginal hyperalgesia, a surrogate marker for endometriosis-related pain. These findings validate fenoprofen as a therapeutic that could be utilized more frequently for endometriosis and suggest the utility of the aforementioned computational drug repurposing approach for endometriosis.

Finding New Tricks for Old Drugs: Tumoricidal Activity of Non-Traditional Antitumor Drugs

Chemotherapy, a traditional method, plays an important role in tumor therapy. Currently, common clinical antitumor drugs have several defects like poor efficacy, side effects, etc. Furthermore, developing new antitumor drugs takes a long time and requires many resources. Recent studies have found that oldies are newbies for the oncologist, such as flavonoid, metformin, aspirin, etc. These non-traditional antitumor drugs (NTADs) are widely used in management of non-cancer diseases, which gained FDA approval for treatment of patients. Increasingly, studies about antitumor action of NTADs have attracted many researchers' interests. A giant amount of studies showed a decrease in cancer incidence in NTAD-treated patients. Several reports outlined a direct inhibitory effect of NTADs on cancer cell growth and antitumoral actions. This review summarized the research progress on antitumor effects of ten NTADs. Retrospective and meta-analyses of trials also showed that these NTADs had preventive effects against cancer in vitro and in vivo. These drugs represent a promising option for cancer treatment, which have clear benefits including clinical safety, obvious curative effect, and saving medical and health resources. Judged from previous reports, future studies will yield valuable data about the profitable effects of these drugs. With a better understanding of its mechanisms of antitumor activity, NTADs may become available for combination with chemotherapy or targeted therapy in clinic.

Effects of cyclooxygenase inhibition on anastomotic healing following large bowel resection in a rabbit model--a randomized, blinded, placebo-controlled trial

PURPOSE

We performed an experimental study in a rabbit model to investigate the effects of a selective Cox-2 inhibitor (Valdecoxib) on anastomotic healing following large bowel resection after 1 week.

MATERIALS AND METHODS

Eighty New Zealand white rabbits were randomized into four groups and underwent a colon resection with end-to-end anastomosis. Group 1 (n = 20) was treated with Valdecoxib, group 2 with Metamizole (Novalgin), group 3 with Resveratrol (specific Cox-1 inhibitor), or a placebo vehicle with similar volume (group 4). Anastomotic healing was tested at the seventh postoperative day by measurement of the bursting pressure in vitro. Immunohistochemical staining of the anastomotic site was performed with polyclonal antibodies (CD31).

RESULTS

There were no significant differences in anastomotic dehiscence, bursting pressure, or vessel density between the treatment and control groups.

CONCLUSION

The application of Valdecoxib does not influence anastomotic healing or new vessel formation in the anastomotic region following large bowel resection.

Tumor Initiation Inhibition Through Inhibition COX-1 Activity of a Traditional Korean Herbal Prescription, Geiji-Bokryung-Hwan, in Human Hepatocarcinoma Cells

Some Korean and oriental herbal prescriptions used for a syndrome expressed as chest paralysis and heartache are thought to be effective for angina pectoris. We investigated the effects of an oriental medicinal prescription, Geiji-Bokryung-Hwan (GBH) consisting of herbs of Cinnamomi Ramulus, Poria Cocos Hoelen (Pachymae Fungus), Moutan Cortex Radicis, Paeoniae Radix, and Persicae Semen, on growth-inhibitory activity and cancer chemopreventive activity in assays representing three major stages of carcinogenesis. The GBH was found to act as an potent inhibitor of cyclooxygenase (COX)-1 only but not as COX-2 inhibitor. Furthermore, the extract mediated anti-inflammatory effects and inhibited COX-associated hydroperoxidase functions (anti-promotion activity). Inhibitory effect of the GBH on the growth of cancer cell lines such as HepG2 cell and Hep3B cell was shown. These data suggest that GBH extracts merit investigation as a potential cancer chemopreventive agent in humans, especially in hepatological cancers.

Chemoprevention of Scutellaria bardata on human cancer cells and tumorigenesis in skin cancer

Scutellaria barbata D. Don (Lamiaceae) (SB) is a perennial herb, which is natively distributed throughout Korea and southern China. This herb is known in traditional Chinese medicine as Ban-Zhi-Lian and in traditional Korean medicine as Banjiryun. SB has been used as an antiinflammatory and antitumor agent. The SB showed strong growth-inhibitory activity and cancer chemopreventive activity in assays representing three major stages of carcinogenesis. The SB was found to act as an antimutagen; it mediated antiinflammatory effects; inhibited cyclooxygenase and hydroperoxidase functions (antipromotion activity). In addition, SB inhibited the development of preneoplastic lesions in carcinogen-treated mouse mammary glands in culture and inhibited tumorigenesis in a mouse skin cancer model. On the other hand, an inhibitory effect of SB on the growth of gynecological cancer cell lines such as HeLa cell and human ovary cancer (HOC) was shown. When HOC cells were treated with SB, the expression of cyclooxygenase-2 was inhibited. These data suggest that SB merits investigation as a potential cancer chemopreventive agent in humans, especially in gynecological cancers.

Prostaglandins in Health and Disease: An Overview

OBJECTIVES

Prostaglandins are a group of biologically active compounds that play major roles in human physiology in both health and disease. They function in many different ways and in all major organs. This article reviews the basic physiology of prostaglandins and their application to specific effects on these systems in normal and abnormal clinical states. The critical therapeutic implications of the use of nonsteroidal antiinflammatory drugs in altering organ homeostasis are also examined.

METHODS

References were taken from Medline, Embase, and Index Medicus from 1966 to September 2005. A search was done with keywords, including prostaglandins, nonsteroidal antiinflammatory drugs, inflammation, arachidonic acid, Cox-1 (cyclooxygenase-1), and Cox-2 (cyclooxygenase-2).

RESULTS

There was a close correlation and predictability between basic prostaglandin physiology and the anticipated effects of these compounds on the heart, lungs, kidneys, gastrointestinal tract, bones and joints, brain, and male and female reproductive systems. These effects are organ and tissue specific. Despite these findings, unexplained and sometimes paradoxical physiologic responses were identified. A prime example of this is the role of prostaglandins in bone metabolism demonstrating both stimulatory and inhibitory effects. In addition all NSAIDs have the potential to impair the normal physiologic effects of prostaglandins depending primarily on the specific organ and the clinical setting.

CONCLUSIONS

Prostaglandins are regulatory compounds that play important roles in many physiologic processes in the human body. An understanding of the basic science of prostaglandins is valuable in anticipating the organ-specific biologic effects of these unique compounds in health and disease. However, at selected sites and under different physiologic conditions, unexplained and sometimes paradoxical effects are generated. Impairment of their regulatory functions can lead to significant short- or long-term organ dysfunction.

COX-2: a molecular target for colorectal cancer prevention

Cyclooxygenase (COX), a key enzyme in the prostanoid biosynthetic pathway, has received considerable attention due to its role in human cancers. Observational and randomized controlled studies in many different population cohorts and settings have demonstrated protective effects of nonsteroidal anti-inflammatory drugs (NSAIDs; the inhibitors of COX activity) for colorectal cancers (CRCs). COX-2, the inducible isoform of cyclooxygenase, is overexpressed in early and advanced CRC tissues, which portends a poor prognosis. Experimental studies have thus identified important mechanisms and pathways by which COX-2 plays an important role in carcinogenesis. Selective COX-2 inhibitors have been approved for use as adjunctive therapy for patients with familial polyposis. The role of COX-2 inhibitors is currently being evaluated for use in wider populations.

Effects of the Geiji-Bokryung-Hwan on carrageenan-induced inflammation in mice and cyclooxygenase-2 in hepatoma cells of HepG2 and Hep3B

We investigated the effects of a Korean traditional prescription, Geiji-Bokryung-Hwan (GBH) consisting of five herbs of Cinnamomi Ramulus (Korean name Geiji), Poria cocos (Bokryung), Moutan Cortex Radicis (Modanpi). Paeoniae Radix (Jakyak) and Persicae Semen (Doin) on tumor growth-inhibitory activity and cancer chemopreventive activity in assays representing three major stages of carcinogenesis. Effects of the GBH extracts on carrageenan-induced edema inflammation using female (C57BL/6XC3H) F1 (B6C3F1) mice and tumorigenesis were examined. Finally, cyclooxygenase metabolites were determined after extracts treatment. These data suggest that GBH extracts merits investigation as a potential cancer chemopreventive agent in humans.

Effects of resveratrol on gene expression in renal cell carcinoma

Studies have shown that Resveratrol (RE) can inhibit cancer initiation, promotion, and progression. However the gene expression profile in renal cell carcinoma (RCC) in response to RE treatment has never been reported. To understand the potential anticancer effect of RE on RCC at molecular level, we profiled and analyzed the expression of 2059 cancer-related genes in a RCC cell line RCC54 treated with RE. Biological functions of 633 genes were annotated based on biological process ontology and clustered into functional categories. Twenty-nine highly differentially expressed genes in RE treated RCC54 were identified and the potential implications of some gene expression alterations in RCC carcinogenesis were identified. RE was also shown to inhibit cell growth and induce cell death of RCC cells. The expression alterations of selected genes were validated using reverse transcription polymerase chain reaction. In addition, the gene expression profiles under different RE treatments were analyzed and visualized using singular value decomposition. The findings from this study support the hypothesis that RE induces differential expression of genes that are directly or indirectly related to the inhibition of RCC cell growth and induction of RCC cell death. In addition, it is apparent that the gene expression alterations due to RE treatment depend strongly on RE concentration. This study provides a general understanding of the overall genetic response of RCC54 to RE treatment and yields insights into the understanding of the cancer preventive mechanism of RE in RCC.

Inhibitory effect of mandarin juice rich in beta-cryptoxanthin and hesperidin on 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone-induced pulmonary tumorigenesis in mice

Previously we reported that a commercial Satsuma mandarin (Citrus unshiu Marc.) juice (MJ), MJ2 and MJ5, especially MJ5, effectively suppressed chemically-induced rat colon carcinogenesis (Int. J. Cancer 88 (2000) 146). MJ2 and MJ5 prepared from MJ have higher amounts of beta-cryptoxanthin and hesperidin than MJ, suggesting that principle chemopreventive factors in MJs may be beta-cryptoxanthin and hesperidin. Present study was conducted to test whether these MJs could modify carcinogenesis in other organ, lung initiated with 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) in male A/J mice. Mice were given an intraperitoneal injection of NNK (10 micromol in saline/mouse) to induce pulmonary neoplasms. They also received MJ, MJ2 or MJ5 as a drinking water at night for 21 weeks, starting 1 week after the NNK injection. Treatments with MJ, MJ2, and MJ5 reduced the incidence of lung tumors and the inhibition by MJ5 (29% reduction) was statistically significant (P<0.05). MJs treatment lowered the multiplicity of lung neoplasms without statistical significance. Immunohistochemically, MJs, especially MJ5, reduced proliferating cell nuclear antigen (PCNA)-positive index in the lung tumors without affecting PCNA index in hyperplastic alveolar cell lesions. These findings might suggest that MJ5, which contain 3.9 mg beta-cryptoxanthin and 100 mg hesperidin in 100 g sample), has chemopreventive ability against NNK-induced mouse lung tumorigenesis.

Inhibition of heat-induced denaturation of albumin by nonsteroidal antiinflammatory drugs (NSAIDs): pharmacological implications

The activity of nonsteroidal antiinflammatory drugs (NSAIDs) in rheumatoid arthritis is not only due to the inhibition of the production of prostaglandins, which can even have beneficial immunosuppressive effects in chronic inflammatory processes. Since we speculated that these drugs could also act by protecting endogenous proteins against denaturation, we evaluated their effect on heat-induced denaturation human serum albumin (HSA) in comparison with several fatty acids which are known to be potent stabilizers of this protein. By the Mizushimas assay and a recently developed HPLC assay, we observed that NSAIDs were slightly less active [EC50 to approximately 10(-5)-10(-4) M] than FA and that the HPLC method was less sensitive but more selective than the turbidimetric assay, i.e. it was capable of distinguishing true antiaggregant agents like FA and NSAIDs from substances capable of inhibiting the precipitation of denatured protein aggregates. In conclusion, this survey could be useful for the development of more effective agents in protein condensation diseases like rheumatic disorders, cataract and Alzheimers disease.

Glomerular, tubular and interstitial nephritis associated with non-steroidal antiinflammatory drugs. Evidence of a common mechanism

AIMS

To study the mechanisms behind NSAID-associated nephropathy.

METHODS

Analysis of published case reports satisfying strict criteria for NSAID nephropathy.

RESULTS

Ninety-seven cases with acute nephritis (AN; 19 patients), minimal change nephropathy (MC; 38 patients), membranous glomerulonephritis (MGN; 19 patients), focal sclerosis (FS; 13 patients) and other glomerulonephritis subgroups (8 patients) were identified. Hypersensitivity reactions were seen in all groups, most often in AN. Proteinuria was more severe in MC and FS than in MGN and unrelated to amount of glomerular deposits. The mean NSAID treatment time was 1.7 months in AN, 8.2 months in MC and 39 months in MGN and associated with amount of glomerular deposits, fusion of podocytes and proteinuria, and inversely associated with hypersensitivity, interstitial damage and renal failure. Rheumatic diseases were common in MGN. At follow-up 68 of 72 patients who had discontinued NSAID treatment had improved, 57 with normal renal function.

CONCLUSIONS

NSAID nephropathy may be caused by hypersensitivity. The reaction is milder than in drug-induced acute tubulointerstitial nephritis, probably because the offending drug inhibits the inflammatory reaction it has started itself. Heavy proteinuria is probably due to lymphokines produced as a result of the immunological response. If the allergic reaction is strong, AN is produced rapidly with severe renal failure but little proteinuria; if it is less violent, immunocompetent cells may develop to produce lymphokines and proteinuria. Immune complexes may be formed eventually, secondary to the increased glomerular permeability, more easily in patients with a hyperactive immune system and with little consequence for renal function.

The clinical spectrum of necrotising fasciitis. A review of 15 cases

BACKGROUND

Necrotising fasciitis represents a spectrum of disease which ranges from fulminant through acute to subacute varieties. While fulminating necrotising fasciitis is a well recognised entity the subacute variety is not.

AIM

To assess six years' experience of necrotising fasciitis at Waikato Hospital.

METHOD

Cases of necrotising fasciitis were identified from discharge statistics for the period 1990-1995. Records were reviewed for clinical features, predisposing factors, microbiology, histology, treatment and outcome.

RESULTS

Fifteen cases were identified of which ten were female. The average age was 55 years (range of 15-92 years). One patient presented with fulminant, eight with acute and six with subacute necrotising fasciitis. Significant blister formation was noted in eight cases. Risk factors were identified in 14 patients including trauma, renal impairment, diabetes mellitus, and various drugs including diclofenac (four patients), naproxen (one patient) and prednisone (two patients). Group A beta haemolytic streptococcus (GABHS) was identified in ten cases. Swab or tissue cultures had the highest yield for isolating the organism. Blood cultures grew GABHS in only three of 12 cases. Eight patients (53%) died. Of the survivors all but one patient required debridement and skin grafting.

CONCLUSIONS

Necrotising fasciitis is a clinical spectrum of disease. It affects a wide age group and can have associated morbidities. It is often a fatal disease. Early recognition, high dose antibiotics and surgical debridement are important in the management of the entire spectrum of necrotising fasciitis.

Cancer chemopreventive activity of resveratrol, a natural product derived from grapes

Resveratrol, a phytoalexin found in grapes and other food products, was purified and shown to have cancer chemopreventive activity in assays representing three major stages of carcinogenesis. Resveratrol was found to act as an antioxidant and antimutagen and to induce phase II drug-metabolizing enzymes (anti-initiation activity); it mediated anti-inflammatory effects and inhibited cyclooxygenase and hydroperoxidase functions (antipromotion activity); and it induced human promyelocytic leukemia cell differentiation (antiprogression activity). In addition, it inhibited the development of preneoplastic lesions in carcinogen-treated mouse mammary glands in culture and inhibited tumorigenesis in a mouse skin cancer model. These data suggest that resveratrol, a common constituent of the human diet, merits investigation as a potential cancer chemopreventive agent in humans.

Cancer Chemopreventive Activity of Resveratrol, a Natural Product Derived from Grapes

Resveratrol, a phytoalexin found in grapes and other food products, was purified and shown to have cancer chemopreventive activity in assays representing three major stages of carcinogenesis. Resveratrol was found to act as an antioxidant and antimutagen and to induce phase II drug-metabolizing enzymes (anti-initiation activity); it mediated anti-inflammatory effects and inhibited cyclooxygenase and hydroperoxidase functions (antipromotion activity); and it induced human promyelocytic leukemia cell differentiation (antiprogression activity). In addition, it inhibited the development of preneoplastic lesions in carcinogen-treated mouse mammary glands in culture and inhibited tumorigenesis in a mouse skin cancer model. These data suggest that resveratrol, a common constituent of the human diet, merits investigation as a potential cancer chemopreventive agent in humans.

Lactoperoxidase-catalysed oxidation of indomethacin, a nonsteroidal antiinflammatory drug, through the formation of a free radical

Lactoperoxidase (LPO, EC 1.11.1.7; donor-H2O2 oxidoreductase) catalyses the oxidation of indomethacin, a nonsteroidal antiinflammatory drug by H2O2 as measured by time-dependent decay of indo-methacin extinction at 280 nm and concurrent appearance of stable oxidation product(s) at 412 nm. From a plot of log Vmax against varying pH of indomethacin oxidation, involvement of an ionizable group of the enzyme having pka = 5.7 could be ascertained for controlling the oxidation process. Spectral studies revealed that LPO-compound II oxidises indomethacin through one-electron transfer and is reduced to the native ferric state as shown by its spectral shift from 430 nm to 412 nm through an isosbestic point at 421 nm. The one-electron oxidation product is a nitrogen-centered free radical detected as a 5,5-dimethyl-l-pyrroline N-oxide (DMPO) adduct (alpha N = 15 G, alpha H beta = 16 G) in electron spin resonance spectroscopy. The free radical is scavenged by reaction with O2 as shown by O2 consumption sensitive to the free-radical trap, DMPO. Binding studies by optical difference spectroscopy indicate that indomethacin binds to LPO with an apparent KD value of 24.5 microM. The free energy change, delta G', for the binding is -26.3 KJ mol-1, suggesting that the interaction is favourable for oxidation. Indomethacin binding remains unaltered by a change of pH from 5.25 to 7.5, presumably because of hydrophobic interaction. The binding is competitive with resorcinol, an aromatic electron donor, showing the KD value to be as high as 100 microM. We suggest that indomethacin interacts at the aromatic donor binding site and is oxidised by one-electron transfer by LPO catalytic intermediates to stable oxidation product(s) through the formation of a free radical.

New agents for cancer chemoprevention

Clinical chemoprevention trials of more than 30 agents and agent combinations are now in progress or being planned. The most advanced agents are well known and are in large Phase III chemoprevention intervention trials or epidemiological studies. These drugs include several retinoids [e.g., retinol, retinyl palmitate, all-trans-retinoic acid, and 13-cis-retinoic acid], calcium, Beta carotene, vitamin E, tamoxifen, and finasteride. Other newer agents are currently being evaluated in or being considered for Phase II and early Phase III chemoprevention trials. Prominent in this group are all-trans-N-(4-hydroxy phenyl)retinamide (4-HPR) (alone and in combination with tamoxifen), 2-difluoromethylornithine (DFMO), nonsteroidal antiinflammatory drugs (aspirin, piroxicam, sulindac), oltipraz, and dehydroepiandrostenedione (DHEA). A third group is new agents showing chemopreventive activity in animal models, epidemiological studies, or in pilot clinical intervention studies. They are now in preclinical toxicology testing or Phase I safety and pharmacokinetics trials preparatory to chemoprevention efficacy trials. These agents include S-allyl-l-cysteine, curcumin, DHEA analog 8354 (fluasterone), genistein, ibuprofen, indole-3-carbinol, perillyl alcohol, phenethyl isothiocyanate, 9-cis-retinoic acid, sulindac sulfone, tea extracts, ursodiol, vitamin D analogs, and p-xylyl selenocyanate. A new generation of agents and agent combinations will soon enter clinical chemoprevention studies based primarily on promising chemopreventive activity in animal models and in mechanistic studies. Among these agents are more efficacious analogs of known chemopreventive drugs including novel carotenoids (e.g., alpha-carotene and lutein). Also included are safer analogs which retain the chemopreventive efficacy of the parent drug such as vitamin D3 analogs. Other agents of high interest are aromatase inhibitors (e.g., (+)-vorozole), and protease inhibitors (e.g., Bowman-Birk soybean trypsin inhibitor). Combinations are also being considered, such as vitamin E with l-selenomethionine. Analysis of signal transduction pathways is beginning to yield classes of potentially active and selective chemopreventive drugs. Examples are ras isoprenylation and epidermal growth factor receptor inhibitors.

Effect of acetylsalicylic acid and dexamethasone on antibody production in adjuvant arthritis

The production of antibodies to IgG and type II collagen occurs in a similar fashion in human rheumatoid arthritis and adjuvant arthritis. In this study, the effect of dexamethasone (DXT) and acetylsalicylic acid (ASA) on antibody synthesis was analysed. Daily treatment with DXT (0.3 mg/kg per day p.o.) or with ASA (200 mg/kg per day p.o.) from day 14 to day 56 after arthritis induction inhibited both the synthesis of antibodies to IgG and type II collagen and also the humoral immune response to the mycobacteria that induced the disease. The immunosuppressive response was similar for both drugs: DXT, which is known to suppress the immune response, and ASA, a classical anti-inflammatory agent.

Aspirin and the prevention of colorectal cancer: a review of the evidence

In all but one of seven recent epidemiologic case-control and cohort studies directly examining the association between aspirin and colorectal cancer and polyps, regular aspirin use reduced the risk of these diseases by about half. Although these studies show a biologically plausible relationship between aspirin and colorectal cancer, information regarding dose and duration and risk change after discontinuation of aspirin is limited and contradictory. Additionally, selection bias, recall bias, and confounding cannot be completed discounted. The one randomized trial of aspirin and placebo showed that aspirin at a dose adequate for preventing myocardial infarction (325 mg every other day) did not reduce colorectal cancer incidence during five years of randomized treatment and follow-up. Further studies need to determine the biologic effects of aspirin, the minimum dose required, and whether other factors, such as age, illnesses, and reasons for aspirin use, modify or confound colorectal cancer development.

Preclinical efficacy evaluation of potential chemopreventive agents in animal carcinogenesis models: methods and results from the NCI Chemoprevention Drug Development Program

In the NCI, Chemoprevention Branch drug development program, potential chemopreventive agents are evaluated for efficacy against chemical carcinogen-induced tumors in animal models. This paper summarizes the results of 144 agents in 352 tests using various animal efficacy models. Of these results, 146 were positive, representing 85 different agents. The target organs selected for the animals model are representative of high-incidence human cancers. The assays include inhibition of tumors induced by MNU in hamster trachea, DEN in hamster lung, AOM in rat colon (including inhibition of AOM-induced aberrant crypts), MAM in mouse colon, DMBA and MNU in rat mammary glands, DMBA promoted by TPA in mouse skin, and OH-BBN in mouse bladder. The agents tested may be classified into various pharmacological and chemical structural categories that are relevant to their chemopreventive potential. These categories include antiestrogens, antiinflammatories (e.g., NSAIDs), antioxidants, arachidonic acid metabolism inhibitors, GST and GSH enhancers, ODC inhibitors, protein kinase C inhibitors, retinoids and carotenoids, organosulfur compounds, calcium compounds, vitamin D3 and analogs, and phenolic compounds (e.g., flavonoids). The various categories of compounds have different spectra of efficacy in animal models. In hamster lung, GSH-enhancing agents and antioxidants appear to have high potential for inhibiting carcinogenesis. In the colon, NSAIDs and other antiinflammatory agents appear particularly promising. Likewise, NSAIDs are very active in mouse bladder. In rat mammary glands, retinoids and antiestrogens (as would be expected) are efficacious. Several of the chemicals evaluated also appear to be promising chemopreventive agents based on their activity in several of the animal models. Particularly, the ODC inhibitor DFMO was active in the colon, mammary glands, and bladder models, while the dithiolthione, oltipraz, was efficacious in all the models listed above (i.e., lung, colon, mammary glands, skin, and bladder).

The effect of fenclofenac on the regeneration of lymphocytes in rats following total body irradiation

The effect of fenclofenac on the regeneration of white blood cells in Sprague-Dawley rats following total body irradiation was investigated. The lowest dose of total body irradiation that would suppress the peripheral blood lymphocyte count by at least 50% was found to be 1.0 Gray in a preliminary experiment. Fenclofenac in a dose of 150 mg/kg/day retarded the regeneration of lymphocytes following total body irradiation of 1 Gray: this effect was also seen in the CD4, CD8 and B-lymphocyte subsets. This suppressive effect in vivo may be due to interference with replicative growth of white blood cells since previous in vitro experiments have shown suppression of lymphocyte growth at a stage later than activation in the cell cycle. The suppressive effects on leucocyte regeneration in vivo suggest that fenclofenac may have promise as an immunosuppressive drug with fewer serious side effects than the currently available immunosuppressive drugs.

In vitro and ex vivo effect of tiaprofenic acid on human peripheral blood mononuclear cells

The effect of the non-steroidal anti-inflammatory drug (NSAID) tiaprofenic acid on different human immune parameters was investigated in vitro or following in vivo administration in healthy adult volunteers. Results from the in vitro study demonstrated an increased mitogen-induced blastogenesis and interleukin 2 (IL-2) production together with a reduced polyclonal immunoglobulin (Ig) secretion in the presence of the drug. Results from the ex vivo study showed that treatment with tiaprofenic acid had no significant effects on the immune parameters investigated, i.e. unstimulated and mitogen-induced proliferation and IL-2 production, spontaneous and stimulated Ig synthesis, lymphocyte subpopulations, serum Ig and complement levels.

Piroxicam and other cyclooxygenase inhibitors: potential for cancer chemoprevention

Piroxicam is a nonsteroidal anti-inflammatory drug (NSAID) widely used for treatment of inflammatory arthritis. Recent experimental and clinical studies suggest that piroxicam, as well as other NSAIDs, may be useful for chemoprevention of colon cancer. While there is less information regarding NSAIDs for chemoprevention of urinary bladder malignancy, there are compelling data which suggest that this should be evaluated. A major effect of NSAIDs is inhibition of cyclooxygenase, the rate-limiting enzyme for conversion of arachidonic acid to important signal molecules, including prostaglandins, which profoundly affect cellular functions in many tissues. The initial enzyme reaction leading to formation of prostaglandin H can be accompanied by cooxidation of xenobiotics resulting in extrahepatic and local tissue production of reactive products which are carcinogenic. The end product prostaglandins, especially prostaglandin E2 (PGE2), are biological modifiers which can significantly affect cell proliferation and tumor growth. High levels of PGE2 stimulate growth of certain tumor cell lines while inhibition of prostaglandin synthesis with indomethacin or piroxicam can cause suppression. The mechanisms for this effect are unclear. Studies in cultured cells exposed to indomethacin show inhibition of G1-to-S phase progression of the cell cycle and a reduction in overall DNA synthesis. It is unclear whether this effect on cell growth results from some direct action of the NSAID or a reduction in prostaglandins or indirectly from modulation of important control signals, such as calcium flux. In addition to cyclooxygenase, NSAIDs can inhibit activity of other enzymes, including phosphodiesterases and cyclic GMP-AMP protein kinases, which may be central to cancer initiation and promotion. NSAIDs can also interfere with transmembrane ion fluxes and with cell-to-cell binding. Prostaglandins can modulate a variety of immunological responses and thereby play an important role in host antitumor immunity. For example, high levels of tissue PGE2 are frequently associated with suppression of immune surveillance and killing of malignant cells. Conversely, immune responses are generally enhanced by drugs that inhibit prostaglandin synthesis. PGE2 can act as a feedback inhibitor for cellular immune processes, such as T-cell proliferation, lymphokine production, and cytotoxicity. This effect is also seen for macrophage activity and natural killer cell toxicity. In general, either increased production of PGE2 or increased sensitivity to normal amounts of PGE2 results in depressed cellular immunity. Cyclooxygenase inhibitors (NSAIDs) such as piroxicam which decrease PGE2 production can stimulate cellular immune function both in vitro and in vivo. A variety of tumor cell lines and human malignancies produce large quantities of prostaglandins.(ABSTRACT TRUNCATED AT 400 WORDS)

Inhibition of the myeloperoxidase-H2O2-Cl- system of neutrophils by indomethacin and other non-steroidal anti-inflammatory drugs

The results presented herein demonstrate that the non-steroidal anti-inflammatory drug (NSAID) indomethacin is a strong inhibitor of the formation of HOCl by murine neutrophils (50% inhibition at 15 microM). Addition of 40 microM indomethacin to activated neutrophils caused 80% inhibition of HOCl formation throughout a 60-min time course while slightly increasing the levels of O2- and H2O2 produced. Comparable degrees of inhibition were achieved when the cells were stimulated with phorbol myristate acetate and with opsonized zymosan. Control experiments indicated that the drug did not act by scavenging HOCl. Direct inhibition of the chlorinating activity of myeloperoxidase (MPO) was confirmed using highly purified human enzyme in vitro. Kinetic analysis of the mechanism of inhibition showed that the drug was competitive with respect to Cl- and uncompetitive with respect to H2O2, showing a Ki of 37 microM. In contrast to its inhibition of the oxidation of Cl- by MPO, indomethacin had no effect on the peroxidative activity of the enzyme (oxidation of 4-aminoantipyrene), nor did it inhibit the activity of several other enzymes involved in H2O2 metabolism, including horseradish peroxidase, catalase, xanthine oxidase, and superoxide dismutase. Finally, it was found that inhibition of HOCl formation was a shared but non-uniform property of many NSAIDs; piroxicam, salicylate, sulindac, ibuprofen, and aspirin were all inhibitory but at widely different concentrations [Ki(app) values of 0.05, 0.18, 0.18, greater than 1, and 3 mM respectively] that correlated only partially with their therapeutic dose range. The results encourage further studies into the possibility that inhibition of HOCl formation may constitute an additional mechanism whereby NSAIDs reduce tissue destruction in chronically inflamed tissues.

The influence of NSAIDs on experimental intestinal anastomoses

Limiting degradation of collagen during the initial phase of wound healing is expected to improve postoperative intestinal strength and thereby decrease chances for anastomotic dehiscence. We studied the influence of four nonsteroid anti-inflammatory drugs on the healing of intestinal anastomoses in rats, with special regard to changes of collagen levels around the anastomoses. Four experimental groups of 20 rats each received daily oral doses of piroxicam, ibuprofen, aspirin, or indomethacin and were compared with a control group. Animals were sacrificed 3 or 7 days after operation. Both morbidity and mortality rate in the experimental groups were high. Collagen, measured as hydroxyproline, levels in anastomotic and adjoining 1-cm intestinal segments were compared with concentrations in control segments resected during operation. After an initial decrease on day 3, hydroxyproline concentrations increased on day 7. In the colon the lowering of hydroxyproline concentrations, which was more pronounced than in the ileum, was significantly reduced by administration of piroxicam and ibuprofen, both in the anastomosis and its proximal segment. On day 7, the increase of hydroxyproline concentrations in the ileum was inhibited by administration of anti-inflammatory drugs. It is concluded that nonsteroidal anti-inflammatory drugs may limit postoperative degradation of collagen in colonic anastomoses, but at the same time may increase the rat's susceptibility to surgical infections.

Helicobacter pylori associated chronic gastritis and peptic ulceration in patients taking non-steroidal anti-inflammatory drugs

Helicobacter pylori is now recognized as a frequent cause of histological chronic gastritis, and this has radically changed our understanding of this common condition. In the light of these developments, the traditional view that non-steroidal anti-inflammatory drugs are one of the common 'environmental' causes of chronic gastritis has been re-examined. Gastric mucosal biopsies have been studied from 430 patients undergoing routine upper gastrointestinal endoscopy, 99 of whom had recently been taking non-steroidal anti-inflammatory drugs. No significant association was found between the use of these drugs and either the presence of chronic gastritis or the frequency of colonization with H. pylori, although there was a strong association (P less than 0.0001) between H. pylori and gastritis. Non-steroidal anti-inflammatory drugs appear, however, to modify the inflammatory process in the gastric body, leading to a lower frequency of atrophic gastritis (P less than 0.05). The majority of peptic ulcers were associated with H. pylori irrespective of non-steroidal anti-inflammatory drug use, but there was a higher frequency of H. pylori negative ulceration in the patients who had used these agents (P less than 0.04). Peptic ulceration was uncommon in the absence of either H. pylori or recent non-steroidal anti-inflammatory drug use.

Gold-naproxen pneumonitis. A toxic drug interaction?

A patient with rheumatoid arthritis developed restrictive lung disease and blood eosinophilia. Gold pneumonitis was suspected but the patient did not improve until naproxen was discontinued as well. Lymphocyte transformation studies suggested hypersensitivity to gold. We hypothesize that naproxen unmasked and perpetuated the manifestations of gold hypersensitivity in our patient.

The role of adaptation in allograft acceptance

The experimental and clinical data suggest that both a decrease of antigen expression and decreased perfusion can protect against immunologically mediated destructive processes. In the adaptation of skin grafts, these factors could be interrelated. Inadequate perfusion might lead to a decreased delivery of substances that stimulate MHC antigen expression. This course of events also could explain the protection in the patient presented here. Immune deposits were completely absent in the protected segment of the kidney, although immune deposits were abundantly present in the remaining part of the kidney, and circulating anti-donor antibodies were demonstrable after the transplanted kidney had been removed. The limited availability of frozen biopsy material has prevented us from comparing the expression of MHC antigens in both kidney segments using monoclonal antibodies. But such studies might be done in experimental kidney transplants with an artificially induced stenosis of the renal artery. Except when an arterial stenosis is present, we have little reason to assume that perfusion gradually decreases in longstanding kidney grafts as it does in skin grafts. Therefore, if adaptation plays a role in the gradual decrease of the sensitivity to rejection in longstanding kidney grafts, this phenomenon must be attributed to a decreased expression of target antigens as a consequence of factors other than decreased perfusion. The most likely candidates are the immunosuppressive drugs, such as cyclosporine and prednisone, which decrease MHC antigen expression. Let me conclude by returning to my main theme of graft adaptation. It seems appropriate to end this review with a quotation from one of Woodruff's original publications on this subject: "If the phenomenon [adaptation] applies to homotransplants of normal tissues to sites other than the eye, I think it almost certain that the clinical homograft problem will be solved; if it does not, the problem may prove insoluble" [9]. Although our insight into the rejection process has increased considerably, we still do not know which factors are most important in determining the long-term survival of primarily vascularized grafts.

Antiinflammatory action of salicylates: aspirin is not a prodrug for salicylate against rat carrageenin pleurisy

A current hypothesis postulates that the antiinflammatory effect of aspirin (acetylsalicylic acid) is mediated by its metabolite salicylic acid through inhibition of PGE2 synthesis. We tested this hypothesis in rats with carrageenin-induced pleurisy. Aspirin or salicylate, given orally, reduced exudation and cell migration into the pleural cavity, aspirin being more potent than salicylate. The antiinflammatory effect of aspirin cannot be explained only in terms of salicylate formation. Doses of aspirin and salicylate that inhibit inflammation by 50% result in salicylate levels in the exudate of 70 +/- 12 and 323 +/- 17 micrograms/ml, respectively. At a significant antiinflammatory dose (100 mg/kg), salicylate did not reduce the prostaglandin and thromboxane content of the exudate. This indicates that inhibition of cyclooxygenase is not a likely mechanism for the antiinflammatory effect of salicylate. Salicylate only reduced the amount of 6-keto-PGF1 alpha in the exudate at higher doses (200 mg/kg), while aspirin at an equally antiinflammatory dose (50 mg/kg) reduced the content of 6-keto-PGF1 alpha, TXB2, PGD2 but not of PGE2 in the exudate. It therefore seems unlikely that an inhibition of PGE2 synthesis is the common mechanism by which aspirin and salicylate exert their antiinflammatory effects. These results do not supported the hypothesis that aspirin is a prodrug for salicylate but rather indicate that both compounds may exert their antiinflammatory effects partly by different mechanisms.

Clinical differences among nonsteroidal antiinflammatory drugs: implications for therapeutic substitution in ambulatory patients

The practice of therapeutic substitution, i.e., replacing one drug with another chemically different drug from the same therapeutic class, represents an important therapeutic modification with potential clinical significance far beyond that of generic substitution. Adverse consequences following therapeutic substitution of nonsteroidal antiinflammatory drugs (NSAID) is of special concern because of substantial differences among these agents in pharmacokinetic, pharmacological, and clinical properties. Therapeutic substitution of NSAID for ambulatory patients may result in compromised clinical outcome because (1) patient response is unpredictable and selection of the optimal agent must be tailored for each patient; (2) substantial differences exist in adverse reaction profiles; (3) drug interaction studies are lacking; and (4) selection of an agent must be individualized to ensure compliance with the dosing regimen. Cost savings achieved through therapeutic substitution of NSAID may be lost by additional overall treatment costs due to adverse reactions or suboptimal therapy. The occurrence of adverse or suboptimal effects in ambulatory patients is more likely if NSAID are substituted without full knowledge of the patient's medical history and clinical status. Communication between the pharmacy and prescribing physician regarding a patient's specific needs is essential for rational substitution among NSAID.

Effects of anti-inflammatory agents on lymphocyte migration stimulated by the interferons, tumor necrosis factor and cutaneous inflammation

Our goal was to examine the effect of anti-inflammatory agents on the migration of lymphocytes to cutaneous inflammatory sites and in response to cytokines. The accumulation of i.v. injected 111In-labelled peritoneal exudate lymphocytes in skin sites of rats injected with KLH to induce DTH reactions, LPS, poly I:C and the cytokines, IFN-gamma, IFN-alpha/beta and tumor necrosis factor was determined. Systemic dexamethasone (DEX) treatment strongly inhibited the migration of lymphocytes in response to all of the stimuli, however, the effective dose of DEX varied widely with the different recruiting agents. The lowest ED50 was observed with LPS, while IFN-alpha/beta was the least inhibited. DEX treatment increased lymphocyte accumulation in the bone marrow and spleen. Pretreatment of lymphocytes with DEX had no effect on their migration, while local i.d. hydrocortisone inhibited migration into the skin. Cyclosporin A treatment had no effect on lymphocyte recruitment in response to any of the cytokines or LPS but significantly inhibited migration to DTH reactions and poly I:C. Treatment of rats with indomethacin, ASA and BW755C produced only a marginal inhibition of lymphocyte migration in response to some of the stimuli tested. DEX is a potent inhibitor of lymphocyte migration to inflammation. In addition to suppressing cytokine production, it can suppress migration to cytokines, probably through inhibiting the effects of these agents on the vascular endothelium. Cyclosporin A decreases lymphocyte accumulation only through its ability to suppress lymphokine production, while inhibitors of arachidonate metabolism have little direct effect on lymphocyte migration.

The effect of non-steroidal anti-inflammatory drugs on phytohaemagglutinin stimulated lymphocytes: relevance to possible therapeutic immunosuppression by fenclofenac

Representatives of seven chemical groups of non-steroidal anti-inflammatory drugs were tested for their effect on activation and replicative growth of phytohaemagglutinin stimulated normal human lymphocytes in vitro at concentrations in the high therapeutic range, and, where possible, at 10 times that concentration. Fenclofenac was noted to be suppressive. Fenclofenac and diclofenac (the only available phenylacetic acid derivatives) were studied in more detail. The two drugs were equipotent in vitro. At low concentrations they enhanced replicative growth, due to cyclo-oxygenase inhibition of cells from some subjects, but at higher concentration they suppressed replicative growth of cells from all subjects, with only a minor effect on activation at very high concentration. However, the potency for clinical effect of fenclofenac and diclofenac is very different, because fenclofenac at therapeutic blood concentrations suppressed replicative growth in vitro, whereas therapeutic concentrations of diclofenac were inactive in lymphocyte suppression. It is suggested that the phenylacetic acid derivative non-steroidal anti-inflammatory drugs may have a composite action in vivo: by inhibition of cyclo-oxygenase they reduce prostaglandin production (and so produce some symptomatic relief in the same manner as the drugs in the other chemical groups of non-steroidal anti-inflammatory agents) and by suppression of lymphocyte replication they may interfere with the pathogenesis of certain chronic rheumatic diseases.

The role of prostaglandins in C3a-mediated suppression of human in vitro polyclonal antibody responses

Suppression of polyclonal antibody responses in human peripheral blood mononuclear cell cultures by human C3a appears to involve the release of endogenous prostaglandins from monocytes. C3a was found, under the experimental conditions employed, to activate the cyclooxygenase pathway of arachidonic acid metabolism with the release of large amounts of the prostaglandin E2 species. Suppression of the protein A-induced polyclonal antibody response by C3a is abrogated by the prostaglandin synthesis inhibitor indomethacin. In addition, physiologic amounts of exogenous PGE2 were able to inhibit polyclonal antibody secretion in a manner similar to the suppression observed when C3a was added to culture. These results suggest that C3a-induced release of prostaglandins could be a major element in immunosuppression induced by C3a.

Interference with tolerance induction in vivo by inhibitors of prostaglandin synthesis

Prostaglandins (PG) have been implicated as modulators of both humoral and cellular immune responses. In order to evaluate a possible role for PG in tolerance, the effect of inhibitors of prostaglandin synthesis on tolerance induction and circumvention has been investigated. Injection of deaggregated human gamma-globulin (DHGG) into A/J mice leads to unresponsiveness to a subsequent challenge with immunogenic aggregated human gamma-globulin (AHGG). Administration of indomethacin (IM) or acetylsalicylic acid (ASA) shortly before and after DHGG injection prevents tolerance induction. PGE2 reverses the tolerance overriding effect provided by IM. IM is not able to overcome unresponsiveness when given 10 and 20 days after tolerance induction, at a time point when both T and B lymphocytes are tolerant. As previously shown, lipopolysaccharide (LPS) both inhibits the induction of tolerance to HGG and circumvents tolerant T helper cells late in tolerance when competent B cells are present. In contrast, IM is unable to circumvent T-helper cell tolerance when given at Day 60 after tolerogen, when B cells (but not T cells) are responsive. Furthermore, LPS acts as an adjuvant, B-cell mitogens, inducer of polyclonal Ig secretion, and primes mice when given with tolerogen, while IM has none of these properties. These results indicate a difference between the effects of IM and LPS on tolerance and a possible role of PG in DHGG-mediated tolerance induction.

Spontaneous relapse of naproxen-related nephrotic syndrome

A number of nonsteroidal anti-inflammatory drugs cause nephrotoxicity characterized by nephrotic syndrome, usually with acute renal insufficiency. Remission of proteinuria and renal insufficiency after discontinuation of nonsteroidal anti-inflammatory drug therapy is characteristic. Relapse of nephrotic syndrome in the absence of nonsteroidal anti-inflammatory drug rechallenge has not previously been reported. Nephrotic syndrome developed in an 80-year-old woman taking naproxen, and remitted after discontinuation of the drug. Nephrotic syndrome relapsed four months later without re-exposure to naproxen or other nonsteroidal anti-inflammatory drugs. Renal biopsy at that time revealed minimal-change disease. The relationship between these two episodes of nephrotic syndrome is discussed with regard to possible pathogenetic mechanisms.

A nonsteroid anti-inflammatory drug exacerbates Coxsackie B3 murine myocarditis

Nonsteroid anti-inflammatory drugs are often used to treat myalgias and arthralgias in enteroviral infections, but their effects on acute viral myocarditis are unknown. The effect of the nonsteroidal anti-inflammatory drug, ibuprofen, on acute viral myocarditis was studied in 75 four week old male BALB/c mice infected with 1.75 X 10(7) plaque-forming units of Coxsackie virus B3 on day 0. Ibuprofen was given intraperitoneally at a dose of 15 mg/kg body weight daily. The mice were assigned to four groups--Group I, 18 uninfected mice given ibuprofen on days 1 to 14; Group II, 18 infected, untreated mice; Group III, 20 infected mice given ibuprofen on days 1 to 14; and Group IV, 17 infected mice given ibuprofen on days 7 to 14. Nine animals in Group I, eight in Group II and seven in Group III were killed on day 7; the remaining mice were killed on day 14. Heart viral cultures and histologic analysis were done. Cultures at days 7 and 14 were all negative. Inflammation and necrosis analyzed in each animal were graded 0 to 4, with grade 4 representing widespread inflammation and necrosis. The heart was histologically normal in all 18 uninfected mice (Group I) given ibuprofen only. Inflammation and necrosis were not significantly different in Group II (infected, untreated) and Group III (infected, treated beginning day 1) mice killed at day 7. Inflammation scores of mice killed on day 14 were 2.1 +/- 0.6 (Group II), 3.1 +/- 0.7 (Group III) and 2.9 +/- 1.0 (Group IV infected, treated days 7 to 14).(ABSTRACT TRUNCATED AT 250 WORDS)