Implication of novel thiazolo-thiophene derivative (MCD-KV-10) for management of asthma

Thiophene-Based Compounds with Potential Anti-Inflammatory Activity

Rheumatoid arthritis, arthrosis and gout, among other chronic inflammatory diseases are public health problems and represent major therapeutic challenges. Non-steroidal anti-inflammatory drugs (NSAIDs) are the most prescribed clinical treatments, despite their severe side effects and their exclusive action in improving symptoms, without effectively promoting the cure. However, recent advances in the fields of pharmacology, medicinal chemistry, and chemoinformatics have provided valuable information and opportunities for development of new anti-inflammatory drug candidates. For drug design and discovery, thiophene derivatives are privileged structures. Thiophene-based compounds, like the commercial drugs Tinoridine and Tiaprofenic acid, are known for their anti-inflammatory properties. The present review provides an update on the role of thiophene-based derivatives in inflammation. Studies on mechanisms of action, interactions with receptors (especially against cyclooxygenase (COX) and lipoxygenase (LOX)), and structure-activity relationships are also presented and discussed. The results demonstrate the importance of thiophene-based compounds as privileged structures for the design and discovery of novel anti-inflammatory agents. The studies reveal important structural characteristics. The presence of carboxylic acids, esters, amines, and amides, as well as methyl and methoxy groups, has been frequently described, and highlights the importance of these groups for anti-inflammatory activity and biological target recognition, especially for inhibition of COX and LOX enzymes.

Development of Thiophene Compounds as Potent Chemotherapies for the Treatment of Cutaneous Leishmaniasis Caused by Leishmania major

Leishmania major (L. major) is a protozoan parasite that causes cutaneous leishmaniasis. About 12 million people are currently infected with an annual incidence of 1.3 million cases. The purpose of this study was to synthesize a small library of novel thiophene derivatives, and evaluate its parasitic activity, and potential mechanism of action (MOA). We developed a structure–activity relationship (SAR) study of the thiophene molecule 5A. Overall, eight thiophene derivatives of 5A were synthesized and purified by silica gel column chromatography. Of these eight analogs, the molecule 5D showed the highest in vitro activity against Leishmania major promastigotes (EC₅₀ 0.09 ± 0.02 µM), with an inhibition of the proliferation of intracellular amastigotes higher than 75% at only 0.63 µM and an excellent selective index. Moreover, the effect of 5D on L. major promastigotes was associated with generation of reactive oxygen species (ROS), and in silico docking studies suggested that 5D may play a role in inhibiting trypanothione reductase. In summary, the combined SAR study and the in vitro evaluation of 5A derivatives allowed the identification of the novel molecule 5D, which exhibited potent in vitro anti-leishmanial activity resulting in ROS production leading to cell death with no significant cytotoxicity towards mammalian cells.

Spleen tyrosine kinase inhibition ameliorates airway inflammation through modulation of NLRP3 inflammosome and Th17/Treg axis

Repeated exposure to the fungal pathogen Aspergillus fumigates triggers spleen tyrosine kinase (SYK) signalling through dectin-1 activation, which is associated with deleterious airway inflammation. β-Glucan-induced dectin-1 signalling activates the NLRP3 inflammasome, which in turn rapidly produces IL-1β, a master regulator of inflammation. IL-1β expression results in Th17/Treg imbalance, pulmonary inflammation, and bystander tissue injury. This study reports that 3,4 methylenedioxy-β-nitrostyrene (MNS), a potent SYK inhibitor, markedly decreased the expression of pro-inflammatory cytokines and increased the expression of anti-inflammatory cytokines in vitro. Furthermore, SYK inhibition markedly decreased β-glucan-induced IL-1β expression, suggesting that SYK is indispensable for NLRP3 inflammasome activation. Decreased IL-1β expression correlated with reduced Th17 response and enhanced immunosuppressive Treg response. Notably, SYK inhibition ameliorated inflammation caused by repeated intranasal β-glucan challenge in BALB/C mice. SYK inhibition also restored the Th17/Treg balance via decreased Th17 and increased Treg responses, as evidenced by decreased IL-17 and ror-γ levels. Additionally, inhibition of SYK increased IL-10 secreting CD4⁺FOXP3⁺ T cells that accompanied reduced T cell proliferation. Decreased IgA in the Bronchoalveolar lavage (BAL) fluid and serum also indicated the immunosuppressive potential of SYK inhibition. Histopathology data revealed that repeated β-glucan challenge caused substantial pulmonary damage, as indicated by septal thickening and interstitial lymphocytic, neutrophil and granulocyte recruitment. These processes were effectively prevented by SYK inhibition, resulting in lung protection. Collectively, our findings suggest that SYK inhibition ameliorates dectin-1- mediated detrimental pulmonary inflammation and subsequent tissue damage. Therefore, SYK can be a new target gene in the therapeutic approach against fungal induced airway inflammation.