Local Scaffold Diversity-Contributed Generator for Discovering Potential NLRP3 Inhibitors.

Deep generative models have become crucial tools in de novo drug design. In current models for multiobjective optimization in molecular generation, the scaffold diversity is limited when multiple constraints are introduced. To enhance scaffold diversity, we herein propose a local scaffold diversity-contributed generator (LSDC), which can be utilized to generate diverse lead compounds capable of satisfying multiple constraints. Compared to the state-of-the-art methods, molecules generated by LSDC exhibit greater diversity when applied to the generation of inhibitors targeting the NOD-like receptor (NLR) family, pyrin domain-containing protein 3 (NLRP3). We present 12 molecules, some of which feature previously unreported scaffolds, and demonstrate their reasonable docking binding modes. Consequently, the modification of selected scaffolds and subsequent bioactivity evaluation lead to the discovery of two potent NLRP3 inhibitors, A22 and A14, with IC50 values of 38.1 nM and 44.43 nM, respectively. And the oral bioavailability of compound A14 is very high (F is 83.09% in mice). This work contributes to the discovery of novel NLRP3 inhibitors and provides a reference for integrating AI-based generation with wet experiments.

SKLB060 Reversibly Binds to Colchicine Site of Tubulin and Possesses Efficacy in Multidrug-Resistant Cell Lines.

BACKGROUND/AIMS: Many tubulin inhibitors are in clinical use as anti-cancer drugs. In our previous study, a novel series of 4-substituted coumarins derivatives were identified as novel tubulin inhibitors. Here, we report the anti-cancer activity and underlying mechanism of one of the 4-substituted coumarins derivatives (SKLB060). METHODS: The anti-cancer activity of SKLB060 was tested on 13 different cancer cell lines and four xenograft cancer models. Immunofluorescence staining, cell cycle analysis, and tubulin polymerization assay were employed to study the inhibition of tubulin. N, N '-Ethylenebis(iodoacetamide) assay was used to measure binding to the colchicine site. Wound-healing migration and tube formation assays were performed on human umbilical vascular endothelial cells to study anti-vascular activity (the ability to inhibit blood vessel growth). Mitotic block reversibility and structural biology assays were used to investigate the SKLB060-tubulin bound model. RESULTS: SKLB060 inhibited tubulin polymerization and subsequently induced G2/M cell cycle arrest and apoptosis in cancer cells. SKLB060 bound to the colchicine site of ß-tubulin and showed antivascular activity in vitro. Moreover, SKLB060 induced reversible cell cycle arrest and reversible inhibition of tubulin polymerization. A mitotic block reversibility assay showed that the effects of SKLB060 have greater reversibility than those of colcemid (a reversible tubulin inhibitor), indicating that SKLB060 binds to tubulin in a totally reversible manner. The crystal structures of SKLB060-tubulin complexes confirmed that SKLB060 binds to the colchicine site, and the natural coumarin ring in SKLB060 enables reversible binding. CONCLUSIONS: These results reveal that SKLB060 is a powerful and reversible microtubule inhibitor that binds to the colchicine site and is effective in multidrug-resistant cell lines.

Design, synthesis, and SAR study of highly potent, selective, irreversible covalent JAK3 inhibitors.

Here, we report the design and synthesis of pyrimidinyl heterocyclic compounds containing terminal electrophiles as irreversible covalent JAK3 inhibitors that exploit a unique cysteine (Cys909) residue in JAK3. Investigation of the structure-activity relationship utilizing kinase assays resulted in the identification of potent and selective JAK3 inhibitors such as T1, T8, T15, T22, and T29. Among them, T29 was verified as a promising JAK3 irreversible inhibitor that possessed the best bioactivity and selectivity against JAKs and kinases containing a cysteine in the residue analogous to Cys909 in JAK3, suggesting that covalent modification of this Cys residue allowed the identification of a highly selective JAK3 inhibitor. Moreover, T29 also displayed a significant anti-inflammatory effect in ICR mice through the inhibition of increased paw thickness, which is worth further optimization to increase its potency and medicinal properties.

Synthesis, in vitro and in vivo evaluation of novel substituted N-(4-(2-(4-benzylpiperazin-1-yl)ethoxy)phenyl)-N-methyl-quinazolin-4-amines as potent antitumor agents.

A novel series of substituted N-(4-(2-(4-benzylpiperazin-1-yl)ethoxy)phenyl)-N-methylquinazolin-4-amines were synthesized and evaluated for their in vitro antiproliferative activity. Among them, compound 7a exhibited the best potency, with IC50 values of 0.029-0.147 µM against four types of cancer cell lines. In addition, 7a was confirmed that it could arrest the cell cycle at G2/M phase and trigger apoptosis. Indirect immunofluorescence staining revealed its anti-tubulin property. Importantly, 7a significantly inhibited tumor growths in HepG2 xenograft models without causing significant loss of body weight, suggesting that 7a is a promising new anticancer agent to be developed.

Flavonoids and biphenylneolignans with anti-inflammatory activity from the stems of Millettia griffithii.

Five new flavonoids, griffinones A-E (1-5), a new biphenylneolignan, griffilignan A (6) and ten known compounds were isolated from the n-hexane and EtOAc extracts of Millettia griffithii. The structures of the new compounds were determined by 1D and 2D NMR, and by HRMS. The anti-inflammatory activity of the isolated compounds was evaluated on lipopolysaccharide (LPS)-induced nitric oxide (NO) production in RAW 264.7 cells. Among the isolated compounds, compounds 1, 2 and 14 showed significant anti-inflammatory activity with IC50 values of 20.4, 2.1 and 35.7µM, respectively and no obvious toxicities were observed at 100µM. Western blot and PCR assay further showed that inhibition of nitric oxide production by compound 2 was associated with suppression of iNOS expression. Modeling studies suggested that the amino group, phenyl ring as well as the isopentenyl tails of compound 2 could help bind to iNOs.

Fragment growth-based discovery of novel TNIK inhibitors for the treatment of colorectal cancer.

Traf2-and Nck-interacting protein kinase (TNIK) plays an important role in regulating signal transduction of the Wnt/ß-catenin pathway and is considered an important target for the treatment of colorectal cancer. Inhibiting TNIK has potential to block abnormal Wnt/ß-catenin signal transduction caused by colorectal cancer mutations. We discovered a series of 6-(1-methyl-1H-imidazole-5-yl) quinoline derivatives as TNIK inhibitors through Deep Fragment Growth and virtual screening. Among them, 35b exhibited excellent TNIK kinase and HCT116 cell inhibitory activity with IC50 values of 6 nM and 2.11 µM, respectively. 35b also shown excellent kinase selectivity, PK profiles, and oral bioavailability (84.64%). At a p. o. dosage of 50 mg/kg twice daily 35b suppressed tumor growth on the HCT116 xenograft model. Taken together, 35b is a promising lead compound of TNIK inhibitors, which merits further investigation.

Associations between Fundamental Movement Skills and Moderate-to-Vigorous Intensity Physical Activity among Chinese Children and Adolescents with Intellectual Disability.

Higher physical activity (PA) levels will obtain more health-related benefits for children and adolescents with intellectual disabilities (ID). The mastery of fundamental movement skills (FMS) potentially correlates with PA. This study aimed to examine the associations of FMS with moderate-to-vigorous intensity physical activity (MVPA) levels in children and adolescents with moderate to severe ID. Moreover, this research analyzes whether there are gender and age differences in the association between these two variables. A total of 93 children and adolescents with ID, aged 8-17 years (mean age = 13.27; SD = 3.35), were recruited from a special school located in western China. The time spent in MVPA was measured using waist-worn accelerometers. FMS proficiency was assessed using the Test of Gross Motor Development 2 (TGMD-2). Children and adolescents with ID tend to have delayed maturity of FMS patterns (locomotor skills t (92) = -16.91, p < 0.001, d = 2.48; object control skills t (92) = -25.39, p < 0.001, d = 3.72; total FMS t (92) = -21.83, p < 0.001, d = 3.20) and lower proficiency in objective control skills (t (92) = 3.989, p < 0.001, d = 0.29). A significant positive correlation was found between MVPA and FMS, and this association was moderated by gender and age. For boys, object control skills were a significant predictor of MVPA time (B = 0.842, p < 0.01), whereas locomotor skills were a significant predictor of MVPA time (B = 0.472, p < 0.05) for girls. For children with ID, object control skills were a significant predictor of MVPA time (B = 0.736, p < 0.05). Proficiency in FMS has a positive effect on increasing the level of MVPA in children and adolescents with ID. Gender and age factors should be considered when implementing FMS intervention programs.

Barriers and Facilitators of Physical Activity Participation among Children and Adolescents with Intellectual Disabilities: A Scoping Review.

Background: Children and adolescents with intellectual disabilities (ID) have low levels of physical activity (PA). Understanding factors influencing the PA participation of this population is essential to the design of effective interventions. The purposes of this study were to identify and map the barriers and facilitators of PA participation among children and adolescents with ID. Methods: A scoping review was conducted in accordance with established methodology. Articles were evaluated for relevance using predetermined inclusion criteria in eight databases. Extracted barriers and facilitators were classified using the social ecological model as individual, interpersonal, or environmental factors. Results: Thirty-two studies published between 1992 and 2020 were included (24 quantitative, 6 qualitative, and 2 mixed-method). Thirty-four factors were identified. The most commonly reported barriers included disability-specific factors, low self-efficacy, lack of parental support, inadequate or inaccessible facilities, and lack of appropriate programs. The most commonly reported facilitators included high self-efficacy, enjoyment of PA, sufficient parental support, social interaction with peers, attending school physical education (PE) classes, and adapted PA programs. Conclusions: Continued exploration of factors influencing PA participation is required among children and adolescents with ID. Future interventions should involve families, schools, and wider support network in promoting their PA participation together.

Molybdenum Disulfide Film Saturable Absorber Based on Sol-Gel Glass and Spin-Coating Used in High-Power Q-Switched Nd:YAG Laser.

In recent years, many different kinds of nonlinear optical materials have been applied to passively Q-switched solid-state lasers. However, the average output powers of these lasers are typically limited to 1 W due to the low damage threshold of the materials. In this study, a molybdenum-disulfide-doped glass-composite absorber was synthesized using the sol-gel method and spin-coating technique. The optical damage threshold of the absorber reached 3.17 J/cm2. Saturation intensity, modulation depth, and nonsaturable loss are 9.35 MW/cm2, 8.41%, and 9.14%, respectively. After inserting the absorber into a linear Nd:YAG laser cavity, the maximum average output power (3.22 W) and stable Q-switched laser pulses duration (132 ns) were obtained.

Nonlinear Optical Response of Graphene Oxide Langmuir-Blodgett Film as Saturable Absorbers.

Two-dimensional (2D) materials as saturable absorbers (SAs) have attracted intense interest for applications in pulsed laser generation because of their distinguishing optical properties. However, the existing methods of preparing SAs were insufficient. Here, we fabricated graphene oxide (GO) SAs by Langmuir-Blodgett (LB) methods for passively Q-switched Nd:YAG laser. The GO sheets were deposited on a quartz plate using the LB method. Two different LB-GO SAs grown under the surface pressure of 22 and 38 mN/m were obtained. Compared with the drop coating method, LB-GO SA exhibited more excellent uniformity, larger nonlinear performance and higher optical transparency. By inserting LB-GO SA into the Nd:YAG laser linear cavity, the short pulse duration of 156 ns and the average output power of 1.313 W were obtained. The slope efficiency was as high as 43.7%, due to low loss of the LB-GO SA. Our results illustrated a new way for preparing the SA using the LB technique.

1.34 µm Q-Switched Nd:YVO4 Laser with a Reflective WS2 Saturable Absorber.

In this work, a Tungsten disulfide (WS2) reflective saturable absorber (SA) fabricated using the Langmuir-Blodgett technique was used in a solid state Nd:YVO4 laser operating at 1.34 µm. A Q-switched laser was constructed. The shortest pulse width was 409 ns with the repetition rate of 159 kHz, and the maximum output power was 338 mW. To the best of our knowledge, it is the first time that short laser pulses have been generated in a solid state laser at 1.34 µm using a reflective WS2 SA fabricated by the Langmuir-Blodgett method.

Discovery of a highly selective JAK3 inhibitor for the treatment of rheumatoid arthritis.

Janus tyrosine kinase 3 (JAK3) is expressed in lymphoid cells and is involved in the signalling of T cell functions. The development of a selective JAK3 inhibitor has been shown to have a potential benefit in the treatment of autoimmune disorders. In this article, we developed the 4-aminopiperidine-based compound RB1, which was highly selective for JAK3 inhibition, with an IC50 of value of 40 nM, but did not inhibit JAK1, JAK2 or tyrosine kinase 2 (TYK2) at concentrations up to 5 µM. Furthermore, RB1 also exhibited favourable selectivity against a panel of representative kinases. In a battery of cytokine-stimulated cell-based assays, this potent inhibitor of JAK3 activity with good selectivity against other kinases could potently inhibit JAK3 activity over the activity of JAK1 or JAK2 (over at least 100-fold). A combination of liquid chromatography-mass spectrometry (LC-MS) experiments validated that RB1 covalently modified the unique cysteine 909 residue in JAK3. In vivo, RB1 exerted significantly improved pathology in the joints of a collagen-induced arthritis mouse model. The reasonable pharmacokinetics properties (F = 72.52%, T1/2 = 14.6 h) and favourable results of toxicology experiments (LD50 > 2 g/kg) suggest that RB1 has the potential to be an efficacious treatment for RA.

Discovery of novel CDK8 inhibitors using multiple crystal structures in docking-based virtual screening.

The cyclin dependent kinase CDK8, along with Med12 and Med13, form the kinase module of the Mediator complex. CDK8 expression associates with the activation of ß-catenin in colon and gastric cancers. Herein, we applied docking-based virtual screening (VS) using the multiple crystal structures to identify several potent CDK8 inhibitors. The appropriate use of multiple crystal structures obtained a better enrichment of CDK8 conformations to cope with the protein flexibility. Later on, the 2D similarity search was used to find the derivatives of the high inhibitory CDK8 inhibitors we discovered by VS. Finally, we measured the dose response behaviors, the IC50 values of compound W-34, W-37, W-8, WS-2 are 6.5 nM, 36 nM, 93 nM, 9 nM, respectively. These novel leads provided good starting points to design and synthesis a series of highly selective and potent CDK8 inhibitors.

Design, synthesis and biological evaluation of 4-anilinoquinoline derivatives as novel potent tubulin depolymerization agents.

A series of novel 4-anilinoquinoline derivatives were synthesized and evaluated for their antiproliferative activities. Among them, 14h exhibited the most potent cytotoxic activity with IC50 values ranging from 1.5 to 3.9 nM against all tested cancer cell lines, and showed promising efficacy in multidrug resistant cancer cells. Flow cytometry assay, immune-fluorescence staining, microtubule dynamics assays and competition assays with EBI identified that 14h was a novel tubulin depolymerization agent by binding to the colchicine site. Importantly, in vivo efficacy evaluation of HCT116 xenograft model, 14h showed efficient antitumor activity without significant loss in body weight. All the results indicated that 14h could be a promising candidate for the treatment of cancer.

Synthesis, activity, and docking study of phenylthiazole acids as potential agonists of PPARγ.

Peroxisome proliferator-activated receptor gamma (PPARγ) is a ligand-mediated transcription factor playing key roles in glucose and lipid homeostasis, and PPARγ ligands possess therapeutic potential in these as well as other areas. In this study, a series of phenylthiazole acids have been synthesized and evaluated for agonistic activity by a convenient fluorescence polarization-based PPARγ ligand screening assay. Compound 4t, as a potential PPARγ agonist with half maximal effective concentration (EC50) 0.75±0.20 µM, exhibited in vitro potency comparable with a 0.83±0.14 µM of the positive control rosiglitazone. Molecular docking and molecular dynamics simulations indicated that phenylthiazole acid 4t interacted with the amino acid residues of the active site of the PPARγ complex in a stable manner, consistent with the result of the in vitro ligand assay.

Synthesis, Activity, and Docking Study of Novel Phenylthiazole-Carboxamido Acid Derivatives as FFA2 Agonists.

Free fatty acid receptor 2 (FFA2), also known as GPR43, is activated by short-chain fatty acids (SCFAs) that are mainly produced by the gut microbiota through the fermentation of undigested carbohydrates and dietary fibers. FFA2 currently appears to be a potential target in the management of obesity, diabetes, inflammatory diseases, and cancer. In the study, a series of novel phenylthiazole-carboxamido acid derivatives has been synthesized and evaluated as potential orthosteric FFA2 ligands for the study of structure-activity relationships. Compound 6e was found to exhibit the twofold potent agonistic activity in the stable hFFA2-transfected CHO-K1 cells (EC50 = 23.1 µm) as that of positive control propionate (EC50 = 43.3 µm). We also reported the results of mutagenesis studies based on the crystal structure of hFFA1 bound to TAK-875 at 2.3 Å resolution to identify important residues for orthosteric agonist 6e inducing FFA2 activation.

Millepachine, a potential topoisomerase II inhibitor induces apoptosis via activation of NF-κB pathway in ovarian cancer.

Millepachine (MIL) was a novel chalcone that was separated from Millettia pachycarpa Benth (Leguminosae). We found MIL induced apoptosis through activating NF-κB pathway both in SK-OV-3 and A2780S cells. Western blot showed that MIL increased the levels of IKKα, p-IKKα/ß, p-IκBα and NF-κB (p65) proteins, and decreased the expression of IκBα protein. Immunohistochemistry analysis indicated that translocation of NF-κB into the nucleus increased in both ovarian cancer cells. EMSA assay proved MIL enhanced NF-κB DNA-binding activity in the nuclear. That specific NF-κB inhibitors alleviated MIL-induced apoptosis suggested NF-κB activation showed a pro-apoptotic function in SK-OV-3 and A2780S cells. Since NF-κB could be activated by double strand breaks and showed a pro-apoptotic function in the DNA damage response, SCGE assay and western blot revealed that MIL caused DNA strand breaks and significantly increased the level of p-ATM protein and further increased the levels of p-IKKα/ß and NF-κB (p65) protein in SK-OV-3 and A2780S cells, while a specific ATM inhibitor could alleviated these effects. Moreover, Topoisomerase II drug screening kit and computer modeling assay were used to prove that MIL induced the production of linear DNA and inhibited the activity of topoisomerase II through binding with Topoisomerase II-Cleaved DNA complex to stabilize the complex. Taken together, our results identified that MIL exhibited anti-tumor activity through inhibiting topoisomerase II activity to induce tumor cells DNA damage, and MIL-activated NF-κB pathway showed a pro-apoptotic function in response to DNA damage.

Discovery of Selective Histone Deacetylase 6 Inhibitors Using the Quinazoline as the Cap for the Treatment of Cancer.

Novel selective histone deacetylase 6 (HDAC6) inhibitors using the quinazoline as the cap were designed, synthesized, and evaluated for HDAC enzymatic assays. N-Hydroxy-4-(2-methoxy-5-(methyl(2-methylquinazolin-4-yl)amino)phenoxy)butanamide, 23bb, was the most potent selective inhibitor for HDAC6 with an IC50 of 17 nM and showed 25-fold and 200-fold selectivity relative to HDAC1 and HDAC8, respectively. In vitro, 23bb presented low nanomolar antiproliferative effects against panel of cancer cell lines. Western blot analysis further confirmed that 23bb increased acetylation level of α-tubulin in vitro. 23bb has a good pharmacokinetic profile with oral bioavailability of 47.0% in rats. In in vivo efficacy evaluations of colorectal HCT116, acute myelocytic leukemia MV4-11, and B cell lymphoma Romas xenografts, 23bb more effectively inhibited the tumor growth than SAHA even at a 4-fold reduced dose or ACY-1215 at the same dose. Our results indicated that 23bb is a potent oral anticancer candidate for selective HDAC6 inhibitor and deserves further investigation.

Development of Purine-Based Hydroxamic Acid Derivatives: Potent Histone Deacetylase Inhibitors with Marked in Vitro and in Vivo Antitumor Activities.

In the present study, a series of novel histone deacetylase (HDAC) inhibitors using the morpholinopurine as the capping group were designed and synthesized. Several compounds demonstrated significant HDAC inhibitory activities and antiproliferative effects against diverse human tumor cell lines. Among them, compound 10o was identified as a potent class I and class IIb HDAC inhibitor with good pharmaceutical profile and druglike properties. Western blot analysis further confirmed that 10o more effectively increased acetylated histone H3 than panobinostat (LBH-589) and vorinostat (SAHA) at the same concentration in vitro. In in vivo efficacy evaluations of HCT116, MV4-11, Ramos, and MM1S xenograft models, 10o showed higher efficacy than SAHA or LBH-589 without causing significant loss of body weight and toxicity. All the results indicated that 10o could be a suitable candidate for treatment of both solid and hematological cancer.

Design, Synthesis, and Evaluation of in Vitro and in Vivo Anticancer Activity of 4-Substituted Coumarins: A Novel Class of Potent Tubulin Polymerization Inhibitors.

In this paper, a series of novel 4-substituted coumarin derivatives were synthesized. Among these compounds 34, 39, 40, 43, 62, 65, and 67 exhibited significant antiproliferative activity toward a panel of tumor cell lines at subnanomolar IC50 values. Compound 65 showed potent antiproliferative ability (IC50 values of 7-47 nM) and retained full activity in multidrug resistant cancer cells. Compound 65 caused G2/M phase arrest and interacted with the colchicine-binding site in tubulin, as confirmed by immune-fluorescence staining, microtubule dynamics assays, and competition assays with N,N'-ethylene-bis(iodoacetamide). Compound 65 reduced the cell migration and disrupted capillary-like tube formation in HUVEC cells. Importantly, compound 65 significantly and dose-dependently reduced tumor growth in four xenografts models including paclitaxel sensitive and resistant ovarian tumors (A2780s and A2780/T), adrmicycin sensitive and resistant breast tumors (MCF-7 and MCF-7/ADR), suggesting that compound 65 is a promising novel antimitotic compound for the potential treatment of cancer.