BW-B 70C

BW-B 70C is a potent and selective inhibitor of 5-lipoxygenase [1].

5-lipoxygenase is an enzyme that transforms essential fatty acids (EFAs) into leukotrienes and is activated by 5-lipoxygenase activating protein (FLAP).

BW-B 70C is a potent and selective 5-lipoxygenase inhibitor. BW-B 70C had high potency and long duration in vivo and was considered as potential anti-asthma drug [1]. In sensitised guinea-pigs, BW B70C (2-50 mg/kg) inhibited bronchoconstriction induced by allergen in a dose-dependent way, which was consistent with the inhibitory activity of BW B70C against 5-lipoxygenase. Also, BW B70C (20 mg/kg) inhibited eosinophil infiltration by 67% [2]. In guinea-pigs, The 5-lipoxygenase inhibitor, BW B70C (30 mg/kg) inhibited leucocyte migration to the airways lumen, leukotriene C4 synthesis by alveolar macrophages and albumin microvascular leakage induced by endotoxin. However, BW B70C didn’t affect vascular leucocyte margination and the blood levels of secreted phospholipase A2 and TNF-α [3]. In a focal cerebral ischemia rat model, BW-B 70C improved neurological deficit scores and decreased infarctions. Also, BW-B 70C reduced 5-lipoxygenase (5-LOX) and inhibited inducible nitric oxide synthase (iNOS) expression through down-regulation of NF-κB [4].

References:
[1].  Payne AN, Jackson WP, Salmon JA, et al. Hydroxamic acids and hydroxyureas as novel, selective 5-lipoxygenase inhibitors for possible use in asthma. Agents Actions Suppl, 1991, 34: 189-199.
[2].  Yeadon M, Dougan FL, Petrovic A, et al. Effect of BW B70C, a novel inhibitor of arachidonic acid 5-lipoxygenase, on allergen-induced bronchoconstriction and late-phase lung eosinophil accumulation in sensitised guinea-pigs. Agents Actions, 1993, 38(1-2): 8-18.
[3].  Bureau MF, De Castro CM, Cortese C, et al. 5-Lipoxygenase and endotoxin-induced microvascular albumin exchanges and leucocyte recruitment in guinea-pig lungs. Eur J Pharmacol, 1997, 324(1): 89-98.
[4].  Jatana M, Giri S, Ansari MA, et al. Inhibition of NF-kappaB activation by 5-lipoxygenase inhibitors protects brain against injury in a rat model of focal cerebral ischemia. J Neuroinflammation, 2006, 3: 12.

G-231A and G+70C Polymorphisms of Endothelin Receptor Type-A Gene could Affect the Psoriasis Area and Severity Index Score and Endothelin 1 Levels.[Pubmed:25814726]

Indian J Dermatol. 2015 Mar-Apr;60(2):211.

BACKGROUND: The etiopathogenesis of psoriasis has not been clearly elucidated although the role of chronic inflammation, imbalance between pro- and anti-inflammatory cytokines, and many immunological events have been established. Endothelin 1 (EDN1) and endothelin receptor type-A (EDNRA) are implicated in the inflammatory process. The relationships between EDN1 and EDNRA polymorphisms with several diseases have been found. AIMS AND OBJECTIVES: This study examined the possible association of EDN1 (G5665T and T-1370G) and EDNRA (G-231A and G + 70C) single nucleotide polymorphisms (SNPs) with the occurence of psoriasis, and evaluated the relationship between genotypes and clinical/laboratory manifestation of psoriasis. MATERIALS AND METHODS: We analyzed genotype and allele distributions of the above-mentioned polymorphisms in 151 patients with psoriasis and 152 healthy controls by real-time PCR combined with melting curve analysis. RESULTS: We did not find significant differences in the genotype and allele distributions of EDN1 T-1370G, EDNRA G-231A, and EDNRA G+70C polymorphisms between patients with psoriasis and healthy controls. Psoriasis area and severity index (PASI) score of EDNRA -231 polymorphic A allele carrying subjects (AA and AA + AG) was higher than that of wild homozygotes (P = 0.044 and P = 0.027, respectively). In addition, EDN1 levels in EDNRA+70 polymorphic C allele carriers (CC + CG) were elevated when compared with GG genotype; however, the difference was at borderline significance (P = 0.05). CONCLUSION: Although there were no associations between studied polymorphisms and psoriasis susceptibility, the PASI score and EDN1 levels seem to be affected by EDNRA G-231A and G + 70C polymorphisms.

Immobilization antigen vaccine adjuvanted by parasitic heat shock protein 70C confers high protection in fish against cryptocaryonosis.[Pubmed:25957883]

Fish Shellfish Immunol. 2015 Aug;45(2):517-27.

The immobilization antigen (iAg) has been demonstrated as a protective immunogen against Cryptocaryon irritans infection. In this study, C-terminal domain of heat shock protein 70 cloned from C. irritans (Hsp70C) was tested for its immuno-stimulatory effects. The iAg and Hsp70C cDNAs were constructed independently in secretory forms and were encapsulated in chitosan nanoparticles. In the first immunization trial, grouper fingerlings orally intubated with iAg and iAg:Hsp70C presented 96% and 100% relative percent survival (RPS), respectively, after a lethal challenge. In the second trial, both iAg and iAg:Hsp70C groups showed 100% RPS and the skin trophont burden was significantly lowered. The iAg:Hsp70C still provides a significantly high protection of 51% RPS at 49 days post immunization, when an even more serious lethal infection occurs. RT-qPCR results showed that Hsp70C could up-regulate the expression of i) T cell markers: Cluster of Differentiation 8 alpha (CD8alpha) and CD4, ii) cytokine genes: Interferon gamma (IFNgamma), Tumor Necrosis Factor alpha (TNFalpha) and Interleukin 12 p40 (IL-12/P40), iii) antibody genes: Immunoglobulin M heavy chain (IgMH) and IgTH, and iv) major histocompatibility complex (MHC-I & MHC-II), in the spleen of iAg:Hsp70C group. Furthermore, significantly high levels of iAg-specific IgM was detected in skin mucus which efficiently immobilized live theronts in iAg- and iAg:Hsp70C-immunized fish at 5 weeks post immunization. Hsp70C significantly increased the number of nonspecific CD8(+) skin leucocytes which exerted cytotoxicity against theronts, although cytotoxic activity showed no difference among the various groups. Because of this complementary cooperation of cellular and humoral immune responses, Hsp70C enhances the efficacy of iAg vaccine and constrains C. irritans infection. In view of the severe loss caused by cryptocaryonosis, application of this parasitic vaccine in farmed and ornamental fish, is worthy to be considered.

Effect of BW B70C, a novel inhibitor of arachidonic acid 5-lipoxygenase, on allergen-induced bronchoconstriction and late-phase lung eosinophil accumulation in sensitised guinea-pigs.[Pubmed:8480540]

Agents Actions. 1993 Jan;38(1-2):8-18.

The actions of BW B70C, an orally available, biologically persistent and selective inhibitor of arachidonic acid 5-lipoxygenase, have been examined in two systems of anaphylaxis in actively sensitised guinea-pigs in vivo. In anaesthetised, artificially ventilated animals pretreated with mepyramine and indomethacin to leave only the "peptidoleukotriene-dependent" component (leukotrienes C4, D4 and E4) of the anaphylactic response, direct inhalation of nebulised allergen resulted in a slowly developing bronchoconstriction which was prevented in a dose-dependent manner by BW B70C (2-50 mg/kg p.o.) administered 1 or 6 h before challenge. In conscious animals fasted overnight and then pretreated with mepyramine to prevent death due to acute bronchial anaphylaxis, exposure to nebulised allergen produced slight respiratory symptoms. When blood and lung samples were analysed 4-48 h after allergen provocation a sustained leukocytosis and pulmonary eosinophil accumulation were observed. In contrast, in food-replete conscious animals, the early respiratory symptoms were still observed upon allergen inhalation, but no significant blood leukocytosis or accumulation of eosinophils in the lungs occurred subsequently. The eosinophil influx induced by allergen in fasted animals was assessed both by histological examination and determination of tissue peroxidase content, two measures which demonstrated reasonable agreement. Administration of a single dose of BW B70C (10 mg/kg p.o.) 1 h prior to allergen challenge did not affect the subsequent eosinophil infiltration 24 h later, but 20 mg/kg given in divided doses (-1 and +12 h) produced 67% inhibition of cell accumulation. A single dose of 50 mg/kg (-1 h) had a similar effect (78% inhibition). The potent glucocorticosteroid betamethasone was used as a reference compound, and 4 mg/kg given as a divided dose (-1 and +7) fully inhibited lung inflammation assessed 24 h after provocation with allergen. BW B70C inhibited both acute and allergic bronchoconstriction and late-phase eosinophil accumulation subsequent to allergen inhalation in guinea-pigs. In view of the apparent requirement for sustained plasma levels of BW B70C in order to prevent late-phase eosinophil recruitment to the lung after a single challenge with allergen, it is unclear whether inhibition of 5-lipoxygenase underlies the observed anti-eosinophil accumulation effects of the compound, but the anti-bronchoconstrictor effects are consistent with the known inhibitory activity of BW B70C against 5-lipoxygenase.

Hydroxamic acids and hydroxyureas as novel, selective 5-lipoxygenase inhibitors for possible use in asthma.[Pubmed:1793063]

Agents Actions Suppl. 1991;34:189-99.

Inhibition of 5-lipoxygenase (5-LO) is a potential target for therapeutic intervention in asthma. Acetohydroxamic acids such as BW A4C are potent and selective 5-LO inhibitors in vitro and also inhibit 5-LO activity in vivo following oral administration. In man, BW A4C is metabolised relatively rapidly (t1/2 = approx. 2h) but nevertheless inhibits 5-LO with reasonable persistence. Chemical modification of BW A4C has resulted in compounds, including the alpha-methyl analogues BW B218C and BW A360C and the hydroxyurea BW B70C, that retain high in vitro potency as selective 5-LO inhibitors and, compared to BW A4C, have a higher potency and longer duration of action in vivo. Members of both the hydroxamic acid and hydroxyurea series of 5-LO inhibitors are presently being considered as potential anti-asthma drugs.