Anti-inflammatory effects and improved metabolic derangements in ob/ob mice by a newly synthesized prenylated benzopyran with pan-PPAR activity

Synthesis of a new 2-prenylated quinoline as potential drug for metabolic syndrome with pan-PPAR activity and anti-inflammatory effects

We have previously reported the total synthesis and structure-activity relationships (SAR) of 2-prenylated benzopyrans with PPAR agonist activity. Herein, we have described the synthesis and PPAR activity of 2-prenylated benzopyrans and 2-prenylated quinolines. The benzopyran nucleus was generated via enamine-catalyzed Kabbe condensation, and the quinoline nucleus via Friedländer condensation. Results demonstrated that both benzopyran (5a) and quinoline (4b) derivatives bearing a γ,δ-unsaturated ester displayed a pan-PPAR agonism. They were full PPARα agonists, but showed different preferences for PPARγ and PPARβ/δ activation. It was noteworthy that quinoline 4b displayed full hPPARα activation (2-fold than WY-14,643), weak PPARβ/δ and partial PPARγ activation. In addition, quinoline 4b showed anti-inflammatory effects on macrophages by reducing LPS-induced expression of both MCP-1 and IL-6. Therefore, 4b emerges as a first-in-class promising hit compound for the development of potential therapeutics aimed at treating metabolic syndrome, metabolic dysfunction-associated fatty liver disease (MAFLD), and its associated cardiovascular comorbidities.

Identification of circRNAs expression profiles and functional networks in parotid gland of type 2 diabetes mouse

BACKGROUND

Circular RNAs (circRNAs) are a novel kind of non-coding RNAs proved to play crucial roles in the development of multiple diabetic complications. However, their expression and function in diabetes mellitus (DM)-impaired salivary glands are unknown.

RESULTS

By using microarray technology, 663 upregulated and 999 downregulated circRNAs companied with 813 upregulated and 525 downregulated mRNAs were identified in the parotid glands (PGs) of type2 DM mice under a 2-fold change and P < 0.05 cutoff criteria. Gene ontology (GO) and kyoto encyclopedia of genes and genomes (KEGG) analysis of upregulated mRNAs showed enrichments in immune system process and peroxisome proliferator-activated receptor (PPAR) signaling pathway. Infiltration of inflammatory cells and increased inflammatory cytokines were observed in diabetic PGs. Seven differently expressed circRNAs validated by qRT-PCR were selected for coding-non-coding gene co-expression (CNC) and competing endogenous RNA (ceRNA) networks analysis. PPAR signaling pathway was primarily enriched through analysis of circRNA-mRNA networks. Moreover, the circRNA-miRNA-mRNA networks highlighted an enrichment in the regulation of actin cytoskeleton.

CONCLUSION

The inflammatory response is elevated in diabetic PGs. The selected seven distinct circRNAs may attribute to the injury of diabetic PG by modulating inflammatory response through PPAR signaling pathway and actin cytoskeleton in diabetic PGs.

Benzopyran hydrazones with dual PPARα/γ or PPARα/δ agonism and an anti-inflammatory effect on human THP-1 macrophages

Peroxisome proliferator-activated receptors (PPARs) play a major role in regulating inflammatory processes, and dual or pan-PPAR agonists with PPARγ partial activation have been recognised to be useful to manage both metabolic syndrome and metabolic dysfunction-associated fatty liver disease (MAFLD). Previous works have demonstrated the capacity of 2-prenylated benzopyrans as PPAR ligands. Herein, we have replaced the isoprenoid bond by hydrazone, a highly attractive functional group in medicinal chemistry. In an attempt to discover novel and safety PPAR activators, we efficiently prepared benzopyran hydrazone/hydrazine derivatives containing benzothiazole (series 1) or 5-chloro-3-(trifluoromethyl)-2-pyridine moiety (series 2) with a 3- or 7-carbon side chain at the 2-position of the benzopyran nucleus. Benzopyran hydrazones 4 and 5 showed dual hPPARα/γ agonism, while hydrazone 14 exerted dual hPPARα/δ agonism. These three hydrazones greatly attenuated inflammatory markers such as IL-6 and MCP-1 on the THP-1 macrophages via NF-κB activation. Therefore, we have discovered novel hits (4, 5 and 14), containing a hydrazone framework with dual PPARα/γ or PPARα/δ partial agonism, depending on the length of the side chain. Benzopyran hydrazones emerge as potential lead compounds which could be useful for treating metabolic diseases.

Synthesis of 2-aminopropyl benzopyran derivatives as potential agents against triple-negative breast cancer

Synthesis of three series of 2-aminopropyl derivatives containing a benzopyran nucleus was performed to evaluate their performance against triple-negative breast cancer cell lines (MDA-MB-231 and MDA-MB-436) and normal breast epithelial cells (MCF10A). For the three series, the cytotoxic activity was as follows: N-methylated derivatives (tertiary amines) 5b, 6b, and 7b > secondary amine benzopyrans 5, 6, and 7 > quaternary amine salts 5c, 6c, and 7c > free phenolic derivatives 5a, 6a, and 7a. The structure-activity relationship showed the importance of the presence of an amine group and a p-fluorobenzyloxy substituent in the chromanol ring (IC50 values from 1.5 μM to 58.4 μM). In addition, 5a, 5b, 6a, and 7b displayed slight selectivity towards tumor cells. Compounds 5, 5a, 5b, 6, 6a, 6c, 7, and 7b showed apoptotic/necrotic effects due to, at least in part, an increase in reactive oxygen species generation, whereas 5b, 5c, 6b, 7a, and 7c caused cell cycle arrest in the G1 phase. Further cell-based mechanistic studies revealed that 5a, 6a, and 7b, which were the most promising compounds, downregulated the expression of Bcl-2, while 5b downregulated the expression of cyclins CCND1 and CCND2. Therefore, 2-aminopropyl benzopyran derivatives emerge as new hits and potential leads for developing useful agents against breast cancer.

Treating NASH by targeting peroxisome proliferator-activated receptors

The pathophysiology of non-alcoholic steatohepatitis (NASH) encompasses a complex set of intra- and extrahepatic driving mechanisms, involving numerous metabolic, inflammatory, vascular and fibrogenic pathways. The peroxisome proliferator-activated receptors (PPARs) α, β/δ and γ belong to the nuclear receptor family of ligand-activated transcription factors. Activated PPARs modulate target tissue transcriptomic profiles, enabling the body's adaptation to changing nutritional, metabolic and inflammatory environments. PPARs hence regulate several pathways involved in NASH pathogenesis. Whereas single PPAR agonists exert robust anti-NASH activity in several preclinical models, their clinical effects on histological endpoints of NASH resolution and fibrosis regression appear more modest. Simultaneous activation of several PPAR isotypes across different organs and within-organ cell types, resulting in pleiotropic actions, enhances the therapeutic potential of PPAR agonists as pharmacological agents for NASH and NASH-related hepatic and extrahepatic morbidity, with some compounds having already shown clinical efficacy on histological endpoints.

30th Annual GP2A Medicinal Chemistry Conference

The Group for the Promotion of Pharmaceutical Chemistry in Academia (GP2A) held their 30th annual conference in August 2022 in Trinity College Dublin, Ireland. There were 9 keynote presentations, 10 early career researcher presentations and 41 poster presentations.