Fengchao Jiang

Design, Synthesis, and Cytoprotective Effect of 2-Aminothiazole Analogues as Potent Poly(ADP-Ribose) Polymerase-1 Inhibitors

A series of novel poly(ADP-ribose) polymerase-1 (PARP-1) inhibitors were designed within 2-aminothiazole analogues (4-10) based on a constructed three-dimensional pharmacophore model. After synthesis, the inhibitory effect on PARP-1 activity and the cytoprotective action of these compounds were tested and evaluated. Among them, compounds 4-6 and 10 appeared to be potent PARP-1 inhibitors with IC(50) values less than 1 microM, which had been perfectly predicted by pharmacophore model. These compounds proved to be highly potent against cell injury induced by H(2)O(2) and oxygen-glucose deprivation (OGD) in PC12 cells. These novel 2-aminothiazole analogues are potentially applicable as neuroprotective agents for the treatment of neurological diseases.

Multifunctional mercapto-tacrine derivatives for treatment of age-related neurodegenerative diseases.

Cooperating mercapto groups with tacrine in a single molecular, novel multifunctional compounds have been designed and synthesized. These mercapto-tacrine derivatives displayed a synergistic pharmacological profile of long-term potentiation enhancement, cholinesterase inhibition, neuroprotection, and less hepatotoxicity, emerging as promising molecules for the therapy of age-related neurodegenerative diseases.

Targeting of MyD88 Homodimerization by Novel Synthetic Inhibitor TJ-M2010-5 in Preventing Colitis-Associated Colorectal Cancer

BACKGROUND The TLR/MyD88 signaling pathway is an important driver of inflammation and cancer and is a possible target for antitumor therapy. METHODS We generated a MyD88 inhibitor (TJ-M2010-5), which was designed to bind to the TIR domain of MyD88 to interfere with its homodimerization, and the TLR/MyD88 signal pathway. We utilized a mouse model of azoxymethane/dextran sodium sulfate (AOM/DSS)-induced colitis-associated cancer (CAC) in combination with TJ-M2010-5 administration to investigate the anti-inflammation-related cancer effect of MyD88 inhibitor in vivo. Data were analyzed with one-way and repeated measures analysis of variance. Differences in survival between groups were compared using the log rank test. All statistical tests were two-sided. RESULTS TJ-M2010-5 inhibited MyD88 homodimerization in transfected HEK293 cells in a concentration-dependent manner and suppressed MyD88 signaling in LPS-responsive RAW 264.7 cells in vitro. In a 10-week CAC mouse model (n = 30 per group), TJ-M2010-5 treatment statistically significantly reduced AOM/DSS-induced colitis and completely prevented CAC development with less related body mass loss, resulted in 0% mortality of treated mice (compared with 53% mortality of control mice), decreased cell proliferation, and increased apoptosis in colon tissue. TJ-M2010-5 treatment also inhibited production of inflammatory cytokines and chemokines (TNF-α, IL-6,G-CSF, MIP-1β, TGF-β1, IL-11, IL-17A, IL-22 and IL-23) and infiltration of immune cells (macrophages, dendritic cells, neutropihls and CD(+)4 T cells) in colon tissues of mice. CONCLUSIONS Our findings suggest that TLR/MyD88 signaling may be a therapeutic target for CAC intervention and MyD88 inhibitors may be a promising therapeutic modality for treating patients with colitis or CAC.

ST09, a Novel Thioester Derivative of Tacrine, Alleviates Cognitive Deficits and Enhances Glucose Metabolism in Vascular Dementia Rats

Chemical entities containing mercapto group have been increasingly attractive in the therapy of central nerve system (CNS) diseases. In the recent study, we screened a series of mercapto‐tacrine derivatives with synergistic neuropharmacological profiles in vitro.

Pharmacological inhibition of MyD88 homodimerization counteracts renal ischemia reperfusion-induced progressive renal injury in vivo and in vitro

The activation of innate immunity via myeloid differentiation factor 88 (MyD88) contributes to ischemia reperfusion (I/R) induced acute kidney injury (AKI) and chronic kidney injury. However, since there have not yet been any effective therapy, the exact pharmacological role of MyD88 in the prevention and treatment of renal ischemia reperfusion injury (IRI) is not known. We designed a small molecular compound, TJ-M2010-2, which inhibited MyD88 homodimerization. We used an established unilateral I/R mouse model. All mice undergoing 80 min ischemia through uninephrectomy died within five days without intervention. However, treatment with TJ-M2010-2 alone significantly improved the survival rate to 58.3%. Co-treatment of TJ-M2010-2 with the CD154 antagonist increased survival rates up to 100%. Twenty-eight days post-I/R of 60 min ischemia without nephrectomy, TJ-M2010-2 markedly attenuated renal interstitial and inhibited TGF-β1-induced epithelial-mesenchymal transition (EMT) of renal tubular epithelial cells. Furthermore, TJ-M2010-2 remarkably inhibited TLR/MyD88 signaling in vivo and in vitro. In conclusion, our findings highlight the promising clinical potential of MyD88 inhibitor in preventing and treating acute or chronic renal I/R injuries, and the therapeutic functionality of dual-system inhibition strategy in IRI-induced AKI. Moreover, MyD88 inhibition ameliorates renal I/R injury-induced tubular interstitial fibrosis by suppressing EMT.

Dendritic Cells Play an Essential Role in Transplantation Responses via Myeloid Differentiation Factor 88 Signaling

BACKGROUND DCs (dendritic cells), play an important role in allo-recognition, but there is no direct evidence that DCs trigger and control allo-responses. In this study, we investigated the role of DCs by using a self-created MyD88 (myeloid differentiation factor 88) inhibitor and a minor antigen-mismatched (HY-mismatched) skin transplantation model in mice. METHODS An HY-mismatched skin allograft model (BALB/c ♂ → BALB/c ♀) using MyD88-knockout mice was employed in this study. WT (Wild-type) BALB/c immature BMDCs (bone marrow dendritic cells) were co-cultured with or without TJ-M2010 in vitro for 12 hours before transfusion of DCs (2× 10(7)/mouse) into recipients of skin transplantations. Wild-type BALB/c BMDCs were stimulated by the TLR9 (Toll-like receptor 9) agonist, CpG (cytidine-phosphate-guanosine), in the presence of TJ-M2010 or not for 12 hours in vitro. Costimulatory molecules CD80/CD86 were analyzed by flow cytometry. WT C57BL/6 naïve T cells stained with CFSE (carboxyfluorescein diacetate succinimidyl ester) were co-cultured with WT BALB/c DCs for 3 days in the presence or absence of TJ-M2010. CD3(+)/CFSE(+) cells were analyzed by flow cytometry. RESULTS TJ-M2010 inhibited DC maturation and T cell proliferation. Permanent survival of the skin allografts was observed in MyD88 knockout (MyD88- KO) mice. However, skin allografts were rejected by MyD88-KO mice infused with wild-type (WT) DCs. More interestingly, after treating the WT DCs with TJ-M2010, the DC infusion could not reverse the tolerance to skin allografts. CONCLUSION This study provided evidence that DCs play an essential role in alloresponses.

Beyond knockout: A novel homodimerization-targeting MyD88 inhibitor prevents and cures type 1 diabetes in NOD mice

INTRODUCTION AND AIMS Studies have reported that myeloid differentiation factor 88 (MyD88) plays an important role in the development of type 1 diabetes (T1D). The aim of this study was to determine the effects of the self-created MyD88 inhibitor, TJ-M2010-6, in preventing and treating T1D. METHODS Molecule docking and co-immunoprecipitation were used to determine the suppressing capability of TJ-M2010-6 on the homodimerization of MyD88. The preventive and therapeutic effects of TJ-M2010-6 were tested in NOD mice. RESULTS TJ-M2010-6 interacted with amino acid residues of the MyD88 TIR domain and inhibited MyD88 homodimerization. Continuous administration of TJ-M2010-6 significantly reduced the onset of diabetes during the observation period in NOD mice (36.4% vs. 80%, P<0.01). Although the immediate TJ-M2010-6 treatment group showed a retardation in the rise of their blood glucose level, the delayed treatment group did not show this effect. Mechanism studies have shown that TJ-M2010-6 treatment significantly inhibits insulitis in vivo. In vitro, TJ-M2010-6 inhibited the maturation of DCs, leading to the suppression of T cell activation and inflammatory cytokine secretion. CONCLUSIONS These results demonstrated that the strategy targeted at the innate immune system using the MyD88 inhibitor had a profound significance in preventing and treating T1D.

Design, synthesis, and evaluation of 2-piperidone derivatives for the inhibition of β-amyloid aggregation and inflammation mediated neurotoxicity

A series of novel multipotent 2-piperidone derivatives were designed, synthesized and biologically evaluated as chemical agents for the treatment of Alzheimers disease (AD). The results showed that most of the target compounds displayed significant potency to inhibit Aβ(1-42) self-aggregation. Among them, compound 7q exhibited the best inhibition of Aβ(1-42) self-aggregation (59.11% at 20 μM) in a concentration-dependent manner. Additionally, the compounds 6b, 7p and 7q as representatives were found to present anti-inflammation properties in lipopolysaccharide (LPS)-induced microglial BV-2 cells. They could effectively suppress the production of pro-inflammatory cytokines such as TNF-α, IL-1β and IL-6. Meanwhile, compound 7q could prevent the neuronal cell SH-SY5Y death by LPS-stimulated microglia cell activation mediated neurotoxicity. The molecular modeling studies demonstrated that compounds matched the pharmacophore well and had good predicted physicochemical properties and estimated IC50 values. Moreover, compound 7q exerted a good binding to the active site of myeloid differentiation factor 88 (MyD88) through the docking analysis and could interfere with its homodimerization or heterodimerization. Consequently, these compounds emerged as promising candidates for further development of novel multifunctional agents for AD treatment.

Short-term pharmacological inhibition of Myd88 homodimerization by a novel inhibitor promotes robust allograft tolerance in mouse cardiac and skin transplantation

BackgroundMost strategies for antirejection and tolerance induction in clinical transplantation have focused on modifying adaptive immunity, it is unclear whether pharmacological suppressing the innate immune system can promote transplant tolerance. MethodsWe inhibited innate immunity by using our self-generated inhibitor of myeloid differentiation factor 88 (MyD88), TJ-M2010-5, and investigated its therapeutic effects and mechanisms in cardiac and skin transplant models. ResultsTJ-M2010-5 directly and indirectly interacted with the Toll/IL-1R domain of MyD88, inhibiting MyD88 homodimerization. In vitro, TJ-M2010-5 inhibited maturation of dendritic cells, which suppressed nuclear translocation of NF-&kgr;B and T cell activation. In vivo, short-term (10 days) monotherapy of TJ-M2010-5 resulted in long time survival of 50% of the cardiac allografts, and longer-term (14 days) combination treatment of TJ-M2010-5 with CD154 mAb resulted in survival of 29% of skin allografts, which outperformed far more than CsA did and stimulated the proliferation of CD4+CD25+FoxP3+ Regulatory T cells in recipient mice. ConclusionsPharmacological inhibition of MyD88 signaling by this novel inhibitor TJ-M2010-5 shows a powerful anti-rejection effect, which may have therapeutic potential in clinical transplantation. The inhibition of both innate and adaptive immunity may be necessary for tolerance induction in nonsolid organs.

Pharmacopore hypothesis generation of BACE-1 inhibitors and pharmacophore-driven identification of potent multi-target neuroprotective agents

A three dimensional (3D) pharmacophore model of Beta-site APP cleaving enzymes 1 (BACE-1) inhibitors with strong capability of activity prediction was generated for pharmacophore-driven identification of potent multi-target neuroprotective agents. It was developed by HypoGen process in Catalyst system from a training set of 74 BACE-1 inhibitors, represented by four features: two hydrogen bond acceptors, one hydrophobic feature, and one positive ionizable feature. And the ion–dipole interactions between P4-site of OM99-2 and residues of BACE-1 was illustrated by using Ligand Fit in Cerius 2. Subsequently, based on the similarity of 3D pharmacophore models of the BACE-1 inhibitors and the poly(ADP-ribose) polymerase-1 (PARP-1) inhibitors, 2-aminothiazole analogues (111–115) with potent PARP-1 inhibition were predicted to be potent molecules against BACE-1. Then, the inhibitory effect on BACE-1 activity and the cytoprotective action against Aβ-induced cell death of them were tested and evaluated. Among them, compound 111 proved to be a potent multi-target neuroprotective agent for the treatment of Alzheimer’s disease.