The effect of IVX-0142, a heparin-derived hypersulfated disaccharide, on the allergic airway responses in asthma.

BACKGROUND: IVX-0142 is a heparin-derived hypersulfated disaccharide devoid of anticoagulant activity while possessing anti-allergic and anti-inflammatory activity in preclinical studies. In a proof-of-concept study, the allergen inhalation challenge model was used to investigate the effect of IVX-0142 in mild atopic asthma. METHODS: Nineteen subjects, not on controller medications, were randomized to an evaluator-blind, placebo-controlled, cross-over study. The effect of a single nebulized dose of IVX-0142 (80 mg) or placebo administered 30 min prior to allergen inhalation was evaluated on the allergic airway responses, airway responsiveness, and airway inflammation. RESULTS: When compared with placebo, 14 and 13 subjects experienced a relatively smaller maximum fall in forced expiratory volume in 1 s (maxFEV(1)%) for the early airway response (EAR) and late airway response (LAR) with IVX-0142, respectively (P < 0.01). The degree of attenuation in the EAR [maxFEV(1)% (mean +/- SE) 26.5 +/- 2.8%vs placebo 31.0 +/- 2.8%, P = 0.059] and LAR (15.6 +/- 2.9%vs placebo 19.0 +/- 2.9%, P = 0.24) with IVX-0142, however, was small and did not reach statistical significance compared with placebo. Similarly, a trend in the attenuation of allergen-induced increase in the absolute sputum cell counts was also observed. No difference in the allergen-induced increase in airway hyper-responsiveness and exhaled nitric oxide was noticed. CONCLUSIONS: The majority of mild atopic asthmatics demonstrated a reduction in the EAR and LAR to IVX-0142. However, the treatment effect observed with a single prechallenge dose of IVX-0142 was small and heterogeneous. The potential anti-allergic and anti-inflammatory effects using multiple higher doses need to be evaluated.

Substituted (2-phenoxyphenyl)acetic acids with antiinflammatory activity. 1.

The synthesis and antiinflammatory activity of a series of substituted (2-phenoxyphenyl)acetic acids are described. Initial screening in the adjuvant arthritis test showed that halogen substitution in the phenoxy ring enhanced activity considerably. Ulcerogenic potential, as measured by the minimum ulcerogenic dose (MUD), was low in almost all the acids tested. [2-(2,4-Dichlorophenoxy)phenyl]acetic acid possessed the most favorable combination of potency with low toxicity, including ulcerogenicity, and this compound is now in therapeutic use.

Substituted 5H-dibenz[b,g]-1,4-oxazocines and related amino acids with antiinflammatory activity.

During an investigation of the antiinflammatory properties of a number of tetracyclic derivatives of 6,8-dichlorodibenz[b,f]oxepin-10(11H)-one, the ring-expanded 1,3-dichloro-5H-dibenz[b,g]-1,4-oxazocine (9) was prepared and found to be considerable pharmacological interest. It was subsequently found that the corresponding ring-opened amino acid 66, a close analogue of the antiinflammatory agent fenclofenac, also possessed significant antiinflammatory activity, superior both to the dibenzoxazocine and to fenclofenac. These findings prompted extensive synthetic programs in both areas, and a number of derivatives in the amino acid series showed potencies considerably in excess of the standard compound. These phenylacetic acids, however, were significantly more ulcerogenic than fenclofenac whereas the corresponding dibenzoxazocines showed few signs of ulcerogenicity at doses up to 1 g/kg.

Substituted (2-phenoxyphenyl)acetic acids with antiinflammatory activity. 2.

A number of polychlorinated (phenoxyphenyl)acetic acids were prepared as close structural analogues of the antiinflammatory compound fenclofenac, [2-(2,4-dichlorophenoxy)phenyl]acetic acid. Increased potency was shown in several of these compounds, in particular, [2-(2,3,5,6-tetrachlorophenoxy) phenyl]acetic acid (8), which was 40 times more potent than fenclofenac in the adjuvant-induced arthritis screen. In further tests it was found to be equipotent with indomethacin but with a much reduced incidence of acute toxicity (LD50 and ulcerogenicity). On chronic dosing, however, serious toxicity problems arose (including anemia, neutrophilia, and severe peritonitis), and this led to the abandonment of further work on the compound. Three further analogues were prepared containing NH, S, and SO moieties bridging the phenyl rings. Although the NH compound bore a very close structural resemblance both to the above O-linked compound and the potent antiinflammatory drug diclofenac, [2-[(2,6-dichlorophenyl)imino]phenyl]acetic acid, it showed low activity in primary screens. Similarly, neither the S- or SO-bridged analogues had potencies that approached that of 8.

The possible occurrence of endogenous anti-inflammatory substances in the blood of injured rats.

1 Using the carrageenin rat paw oedema test as an assay, an attempt has been made to confirm the presence of anti-inflammatory activity in the blood of rats with a chronic inflammatory lesion induced by a polyester sponge, and to relate such activity to the systemic anti-inflammatory effect exerted in situ by the lesion. In addition, plasma from rats given acetic acid intraperitoneally has been examined for anti-inflammatory properties. 2 The activity of serum obtained from sponge-bearing adrenalectomized Wistar rats did not differ significantly from that obtained from animals without implants. Furthermore, implanted sponges exerted no systemic anti-inflammatory effect. 3 Similar experiments were performed in sponge-bearing adrenalectomized Sprague-Dawley rats, plasma instead of serum being examined for anti-inflammatory activity. The plasma removed from such animals possessed no anti-inflammatory activity, whilst implanted sponges exerted a small, yet significant, systemic inhibitory effect. 4 When the irritancy of sponge implants was augmented with croton oil, more marked systemic anti-inflammatory effects were observed. However, the plasma obtained from rats injured in this manner exerted no anti-inflammatory effect. 5 No anti-inflammatory activity could be detected in plasma samples obtained from rats treated with doses of acetic acid capable of producing pronounced systemic anti-inflammatory effects. 6 It was concluded that the induction of these inflammatory lesions in rats does not appear to lead to a detectable release of endogenous anti-inflammatory substances into the circulation.

Relationship between the anti-inflammatory and irritant properties of inflammatory exudate.

1. Using the rat paw oedema assay procedure a comparison was made between the anti-inflammatory and irritant properties of the inflammatory exudate obtained from polyester sponges implanted subcutaneously in adrenalectomized rats. Where necessary, comparison was also made with a known counter-irritant, carrageenin.2. A significant correlation between the anti-inflammatory and irritant properties of sponge exudate was observed when each parameter was determined in relation to dose. A similar result was obtained with carrageenin.3. A comparison of the two activities of sponge exudate samples harvested at various times following sponge implantation did not give a significant correlation although in each case significant anti-inflammatory activity was accompanied by marked irritation.4. Time-effect curves of the two activities of sponge exudate showed a significant correlation over the time period examined. However, no such correlation was obtained using carrageenin.5. Both activities of sponge exudate were retained following dialysis.6. These findings are discussed in relation to a counter-irritant mode of action for sponge exudate.

Anti-inflammatory and related properties of 2-(2,4-dichlorophenoxy)phenylacetic acid (fenclofenac).

Fenclofenac was shown to possess anti-inflammatory, antinociceptive and antipyretic properties as measured by tests in rats that detect clinically active compounds. In a chronic test for assessing anti-inflammatory activity (established adjuvant arthritis), it was approximately equipotent to alclofenac, fenoprofen calcium and phenylbutazone, more potent than acetylsalicylic acid and ibuprofen, but was less potent than diclofenac sodium, indomethacin, ketoprofen and naproxen. In contrast, the potency of fenclofenac in acute tests for anti-inflammatory, antinociceptive and anti-pyretic activity was generally lower, the drug being approximately equipotent to acetylsalicylic acid in such tests. The anti-inflammatory activity of fenclofenac was not mediated via the pituitary-adrenal axis or a counter-irritant action. Fenclofenac was shown to have remarkably low gastric ulcerogenic potential, both acutely and chronically.

Effect of fenclofenac on prostaglandin production in carageenin air bleb exudates in rats.

Employing a modified carrageenin air bleb technique in rats, the effect was studied of fenclofenac and standard drugs (acetylsalicylic acid, indomethacin and phenylbutazone) on prostaglandin production in inflammatory exudate. In common with the standard drugs, fenclofenac reduced exudate prostaglandin levels, being approximately equipotent with phenylbutazone in this respect. Also, an attempt was made to relate the effect of fenclofenac and standard drugs on prostaglandins to their acute anti-inflammatory activity as determined in a modified carrageenin paw oedema test in rats. Whilst acetylsalicylic acid and phenybutazone significantly inhibited oedema at doses producing 80% inhibition of prostaglandin production in air bleb exudate, fenclofenac and indomethacin did not. The overall results were considered to support the view expressed by other workers that the acute anti-inflammatory activity of acidic anti-inflammatory agents does not result solely, if at all, from inhibition of prostaglandin synthesis.

Effects of salicylate vs. aspirin on renal prostaglandins and function in normal and sodium-depleted dogs.

The effects of aspirin (acetylsalicylate) (ASA) and nonsteroidal antiinflammatory drugs (NSAIDs) on renal prostaglandin (PG) biosynthesis and function have been studied extensively. In contrast, the in vivo effects of a nonacetylated salicylate (SA), such as sodium SA, on renal function have not been well characterized. No studies have examined the effects of SA on renal function in a situation in which the maintenance of normal kidney function is dependent upon intact renal PG synthesis (i.e., sodium restriction-elevated plasma renin activity). To evaluate the effects of SA vs ASA and/or a NSAID, normal and sodium-restricted anesthetized dogs were treated with SA and then meclofenamate (MECLO) or ASA followed by MECLO. In the normal animals, SA significantly decreased renal PGE2 and PGF2 alpha excretion. After SA a significant amount of MECLO-suppressible PGE2 and PGF2 alpha synthesis remained intact. Compared to SA, with ASA there was a greater decrease in PG excretion, with no further decrease in PG excretion with subsequent MECLO treatment. In the sodium-restricted animals (plasma renin activity, 18-24 ng of angiotensin l/ml/hr) ASA decreased PGE2 excretion but SA did not. In these animals SA did not cause renal vasoconstriction. Additional groups of sodium-restricted animals were studied with extremely high doses of ASA and SA (90 mg/kg) to elevate plasma SA to 200 to 250 micrograms/ml. In these animals SA did decrease PGE2 excretion significantly, but only to levels seen typically in normal animals and, after SA, a large amount of PGE2 excretion could be suppressed by MECLO.(ABSTRACT TRUNCATED AT 250 WORDS)

Identification of a new HLA-DRB5 allele, DRB5*0112, by routine PCR-SSP.

We describe the identification of a new HLA-DRB5 allele found in two members of a British Caucasoid family. Genomic analysis of exon 2 revealed a novel sequence. The name DRB5*0112 has been assigned to this allele by the WHO Nomenclature Committee, and the EMBL sequence database accession number for this is AJ427352. DRB5*0112 has several unique sequence features when compared to other DRB5 alleles, and comparison with all known DRB1/3/4/5 alleles indicates this to have arisen as a result of intraexonic recombination between a DRB5-containing haplotype and one carrying DRB1*09.

Salicylic acid causes a diuresis and natriuresis in normal and common bile-duct-ligated cirrhotic miniature swine.

In patients with liver disease, or in normal subjects who are sodium-depleted, the administration of either a nonsteroidal anti-inflammatory drug or acetylsalicylate (aspirin) has a detrimental effect on the kidney; profound renal vasoconstriction and the retention of sodium and water may occur. We observed recently that salicylate (SA), in contrast to meclofenamate (MECLO) or aspirin, caused a diuresis and natriuresis in the sodium-depleted dog. To determine if SA would similarly affect the kidneys in a cirrhotic subject, the effects of SA (40 mg/kg) and subsequent MECLO treatment (2 mg/kg) were evaluated in five normal and six common bile-duct-ligated (CBDL) miniature swine. All six CBDL animals showed signs of biliary cirrhosis and four of the six were ascitic at the time of study. SA did not significantly alter renal blood flow or glomerular filtration rate in either the normal or CBDL animals. In both groups, SA caused a significant diuresis and natriuresis. MECLO, given after SA, caused a reduction in renal blood flow in the normal but not in the CBDL animals, but did not alter glomerular filtration rate in either group. In the CBDL animals, when MECLO was given alone a significant decrease in renal blood flow occurred. MECLO abolished the SA-induced diuresis and natriuresis in the normal swine but only affected the SA-mediated natriuresis in the CBDL animals. SA significantly reduced renal prostaglandin E2 excretion in both groups. With MECLO, prostaglandin E2 excretion was reduced further in the normals but not in the CBDL animals. These data demonstrate that SA does not produce detectable renal vasoconstriction in the cirrhotic pig.(ABSTRACT TRUNCATED AT 250 WORDS)

Used leucodepletion filters as a source of large quantities of DNA suitable for the study of genetic variations in human populations.

UNLABELLED: A simple technique for developing large control panels with large quantities of DNA suitable for studies in population genetics was established. BACKGROUND AND OBJECTIVES: Both a lack of suitable controls and insufficient quantities of DNA for repeated analysis of the same control group often hamper the investigation of genetic markers for disease. MATERIALS AND METHODS: Using a waste product from routine blood donation, we describe a simple method that allows the investigator to extract large amounts of DNA. RESULTS: A mean of 1520 microg of DNA per sample was obtained. The DNA obtained remains suitable for polymerase chain reaction and sequencing techniques after 2 years of storage at both 4 degrees C and -40 degrees C. CONCLUSION: This technique allows the development of a large panel of controls with sufficient quantities of genomic DNA for thousands of tests.