2-Amino-4-(3,4-(methylenedioxy)benzylamino)-6-(3-methoxyphenyl)pyrimidine is an anti-inflammatory TLR-2, -4 and -5 response mediator in human monocytes

Abstract

Objective and design To elucidate the influence of 2-amino-4-(3,4-(methylenedioxy)benzylamino)-6-(3-methoxyphenyl)pyrimidine (AMBMP), a canonical Wnt/β-catenin pathway activator, on the inflammatory response of TLR-engaged innate cells in vitro. Material or subject Primary human monocytes. Treatment AMPMB (0–10 μM), LPS (0–1.0 μg/ml), Pam3CSK4, FSL-1, or S. typhimurium flagellin (0–0.25 μg/ml). Methods TLR-induced cytokine release (TNF, IL-6, IL-12 p40) was monitored by ELISA while Wnt-related signals (GSK3β, p65, IκB, β-catenin) were assessed by Western blot, pharmaceutical inhibition and gene silencing. Results AMBMP induced the rapid phosphorylation of NFκB p65 at Ser536 and abrogated total IκB, accompanied by a subsequent increase in pro-inflammatory cytokine production (TNF, IL-6, IL-12 p40) in otherwise naive monocytes. However, in TLR2, -4 and -5-engaged monocytes, AMBMP-suppressed cytokine production. In the context of LPS stimulation, this occurred concomitant with the phosphorylative inactivation of GSK3β at Ser9, β-catenin accumulation and abrogation of NFκB p65 phosphorylation. AMBMP-mediated suppression of the TLR4 - induced inflammatory response was reversed by two pharmaceutical Wnt/β-catenin pathway inhibitors, IWP-2 and PNU-74654 and by Wnt3a silencing. Conclusions Herein, we show that AMBMP induces canonical Wnt signaling events and acts as a suppressor of inflammation in surface TLR-engaged primary human monocytes.

JAK3 restrains inflammatory responses and protects against periodontal disease through Wnt3a signaling

“…Moreover, the downstream responders of canonical Wnt3a signaling, GSK3β-β-catenin, can suppress bacterial-induced inflammation through the binding of β-catenin to NF-κB (21)(22)(23). We and others have demonstrated that Wnt3a canonical signaling restrains TLR4-mediated inflammation in innate immune cells (24)(25)(26)(27). Further, the expression of Wnt3a and its suppressor, DKK1, has been reported to be associated with the progression of inflammation and is also involved in periodontal disease (26,28).…”

“…Since Wnt3a has been demonstrated to suppress TLR-mediated inflammation (20,27,45,46) in monocytes or macrophages, we next examined whether Wnt3-mediated GSK3β-βcatenin signaling restrains P. gingivalis-induced inflammatory responses. We found that siRNA-mediated Wnt3a or Dvl3 silencing led to a significant increase in the production of inflammatory cytokines, including TNFα, IL-6, and IL-12P40, in P. gingivalis-stimulated monocytes (Fig.…”

Glycogen Synthase Kinase 3β Modulates the Inflammatory Response Activated by Bacteria, Viruses, and Parasites

“…Among these types of compounds, it is worth mentioning the cell permeable small molecule AMBMP that is a recognized canonical Wnt/b-catenin activator, the g-secretase and notch inhibitor DAPT, and the novel benzoxazole derivative K313 with immunosuppressive activity toward T cell proliferation. They all inhibit the activity of GSK3b by increasing the relative abundance of phospho-GSK3b-Ser9 (82)(83)(84). (Table S1), suggesting that these molecules may be used as effective GSK3b inhibitors of LPS-induced inflammation.…”

FLCN-regulated miRNAs suppressed reparative response in cells and pulmonary lesions of Birt-Hogg-Dubé syndrome

“…Accordingly, its downstream component β-Catenin was down-regulated (figure 5D). Whereas, an activator of β-Catenin21 reversed the effect of both miR-424–5p and let-7d-5p mimics on induction of MET in HELF cells (figure 5E). Noted of, FLCN knockdown alone in HELF cells did not show WNT signalling disruption (see online supplementary figure S2), yet both miR-424–5p and let-7d-5p mimics did, and importantly, both mimics worked in the condition of FLCN knockdown (see online supplementary figure S4).…”