Synthesis,anti-inflammatory,analgesic and antioxidant activities of some tetrasubstituted thiophenes

Sets of tetrasubstituted thiophene esters 4a-4g, 5a-5f and 6a-6e were synthesized by reaction of 1-(α-Carbomethoxy-β-aminothiocrotonoyl)-aryl/aroyl amines (3) with 3-(bromoacetyl)coumarin, 1,4-dibromodiacetyl and chloroacetone respectively. The compound 3 were synthesized by nucleophilic addition of aryl/aroylisothiocyanate and enamine (2). The synthesized targeted compounds (4a-4g, 5a-5f and 6a-6e) were evaluated for their in vivo anti-inflammatory activity in carrageenin-induced rat hind paw oedema model at three graded doses employed at 10, 20 and 40 mg/kg body weight using mefanamic acid, ibuprofen and in vivo analgesic activity in acetic acid induced writhing response model at 10 mg/kg dose using ibuprofen as standard drug. The compounds 4a-4f, 5c, 5f, 6c and 6e were evaluated for their in vitro antioxidant nitric oxide radical scavenging assay at the concentrations of 5, 10, 15, 20, 25, 30 and 35 μg/mL using ascorbic acid as standard drug. Among all the targeted compounds 4c showed maximum anti-inflammatory activity of 71% protection at 10 mg/kg and 77% protection at 20 mg/kg to inflamed paw and analgesic activity of 56% inhibition and also maximum in vitro nitric oxide radical scavenging activity having IC₅₀ value 31.59 μg/mL.     

Transient Exposure of Enalapril Normalizes Prenatal Programming of Hypertension and Urinary Angiotensinogen Excretion

Maternal low protein diet programs offspring to develop hypertension as adults. Transient exposure to angiotensin converting enzyme inhibitors or angiotensin II receptor blockers can result in improvement in hypertension. Male rats whose mothers received a low protein diet during the last half of pregnancy were given either vehicle, continuous enalapril (CE) in their drinking water or were given transient enalapril exposure (TE) after weaning at 21 days of age. The TE group had enalapril in their drinking water for 21 days starting from day 21 of life. All rats were studied at 6 months of age. Vehicle treated rats whose mothers were fed a low protein diet were hypertensive, had albuminuria, and demonstrated upregulation of the intrarenal renin-angiotensin system as evidenced by higher urinary angiotensinogen and urinary angiotensin II levels. In low protein rats both continuous and transient exposure to enalapril normalized blood pressure, urinary angiotensinogen and urinary angiotensin II levels at 6 months of age, but only continuous administration of enalapril decreased urinary albumin excretion. These data support the importance of the intrarenal renin-angiotensin system in mediating hypertension in programmed rats and transient exposure to enalapril can reprogram the hypertension and dysregulation of the intrarenal renin-angiotensin system.     

Association of Cytotoxic T-Lymphocyte Antigen 4 (CTLA4) and Thyroglobulin (TG) Genetic Variants with Autoimmune Hypothyroidism

Autoimmune hypothyroidism is known to be caused by immune responses related to the thyroid gland and its immunological feature includes presence of autoimmune antibodies. Therefore the aim was to analyze presence of anti-TPO antibodies in hypothyroidism patients in Gujarat. Cytotoxic T-Lymphocyte Antigen 4 (CTLA4) is one of the susceptibility genes for various autoimmune diseases. Hence, exon1 +49A/G and 3’UTR CT60A/G single nucleotide polymorphisms (SNPs) in CTLA4 and its mRNA expression levels were investigated in autoimmune hypothyroidism patients. Thyroglobulin (TG) is known to be associated with autoimmune thyroid disorders and thus exon 33 (E33) SNP in TG was investigated. We analyzed the presence of anti-TPO antibodies in the plasma samples of 84 hypothyroidism patients and 62 controls by ELISA. PCR-RFLP technique was used for genotyping of polymorphisms. sCTLA4 and flCTLA4 mRNA expression levels were assessed by real time PCR. 59.52% of hypothyroid patients had anti-TPO antibodies in their circulation. The genotype and allele frequencies differed significantly for +49A/G (p = 0.0004 for +49AG, p = 0.0019 for +49GG & p = 0.0004 for allele), CT60 (p = 0.0110 for CT60AG, p = 0.0005 for CT60GG & p<0.0001 for allele) and TG E33 (p = 0.0003 for E33TC p<0.0001 for E33CC& p<0.0001 for allele) SNPs between patients and controls. Patients had significantly decreased mRNA levels of both sCTLA4 (p = 0.0017) and flCTLA4 (p<0.0001) compared to controls. +49A/G and CT60 polymorphisms of CTLA4 were in moderate linkage disequilibrium. Logistic regression analysis indicated significant association of CT49A/G, CT60A/G and TG exon 33 polymorphisms with susceptibility to autoimmune hypothyroidism when adjusted for age and gender. Our results suggest +49A/G and CT60 polymorphism of CTLA4 and E33 polymorphism of TG may be genetic risk factors for autoimmune hypothyroidism susceptibility and down regulation of both forms of CTLA4 advocates the crucial role of CTLA4 in pathogenesis of autoimmune hypothyroidism.     

Synthesis,Anti-Hiv Activity,and Biological Properties of 2′,3′-Didehydro-2′,3′-Dideoxythwidine (d4T)

Abstract

D4T is a thymidine analogue with an in vitro potency against HIV comparable to that of AZT but is less toxic to a variety of cell lines including human hemopoietic progenitor cells.     

Biaryl diacid inhibitors of human s-PLA2 with anti-inflammatory activity

Twenty-four hydrophobic dicarboxylic acids are described which were evaluated as inhibitors of 14 kDa human platelet phospholipase A2 (HP-PLA2). In general, biarylacetic acid derivatives were found to be more active than biaryl acids or biarylpropanoic acids. More potent inhibitors were obtained when hydrophobic groups were attached to the biaryl acid nucleus using an olefin linkage as compared to an ether linkage. Compounds with larger hydrophobic groups were usually more potent inhibitors of HP-PLA2. Five of the compounds disclosed in this report (2, 4, 28, 36b and 36i) were found to possess significant anti-inflammatory activity in a phorbol ester induced mouse ear edema model of chronic inflammation.     

Structure-activity relationship studies of flavopiridol analogues

Cyclin dependent kinases (CDKs) along with the complementary cyclins form key regulatory checkpoint controls on the cell cycle. Flavopiridol is a synthetic flavone that shows potent and selective cyclin-dependent kinase inhibitory activity. In this paper, we report modifications of the 3-hydroxy-1-methylpiperidinyl (D ring) of flavopiridol and their effect on CDK inhibitory activity.     

1-(2,3-Dideoxy-3-Fluoro-β-D-Ribofuranosyl)Tine (FDDT). Improved Preparation and Evaluation as a Potential Anti-Aids Agent

Abstract

3′-Deoxy-3′-fluorothymidine was prepared and evaluated as a potential anti-AIDS agent.     

Characterization of a 12-kilodalton rhodanese encoded by glpE of Escherichia coli and its interaction with thioredoxin

Rhodaneses catalyze the transfer of the sulfane sulfur from thiosulfate or thiosulfonates to thiophilic acceptors such as cyanide and dithiols. In this work, we define for the first time the gene, and hence the amino acid sequence, of a 12-kDa rhodanese from Escherichia coli. Well-characterized rhodaneses are comprised of two structurally similar ca. 15-kDa domains. Hence, it is thought that duplication of an ancestral rhodanese gene gave rise to the genes that encode the two-domain rhodaneses. The glpE gene, a member of the sn-glycerol 3-phosphate (glp) regulon of E. coli, encodes the 12-kDa rhodanese. As for other characterized rhodaneses, kinetic analysis revealed that catalysis by purified GlpE occurs by way of an enzyme-sulfur intermediate utilizing a double-displacement mechanism requiring an active-site cysteine. The K(m)s for SSO(3)(2-) and CN(-) were 78 and 17 mM, respectively. The apparent molecular mass of GlpE under nondenaturing conditions was 22.5 kDa, indicating that GlpE functions as a dimer. GlpE exhibited a k(cat) of 230 s(-1). Thioredoxin 1 from E. coli, a small multifunctional dithiol protein, served as a sulfur acceptor substrate for GlpE with an apparent K(m) of 34 microM when thiosulfate was near its K(m), suggesting that thioredoxin 1 or related dithiol proteins could be physiological substrates for sulfurtransferases. The overall degree of amino acid sequence identity between GlpE and the active-site domain of mammalian rhodaneses is limited ( approximately 17%). This work is significant because it begins to reveal the variation in amino acid sequences present in the sulfurtransferases. GlpE is the first among the 41 proteins in COG0607 (rhodanese-related sulfurtransferases) of the database Clusters of Orthologous Groups of proteins (http://www.ncbi.nlm.nih.gov/COG/) for which sulfurtransferase activity has been confirmed.