The growing resistance to current first-line antimalarial drugs represents a major health challenge. To facilitate the discovery of new antimalarials, we have implemented an efficient and robust highthroughput cell-based screen (1,536-well format) based on proliferation of Plasmodium falciparum (Pf) in erythrocytes. From a screen of Ϸ1.7 million compounds, we identified a diverse collection of Ϸ6,000 small molecules comprised of >530 distinct scaffolds, all of which show potent antimalarial activity (<1.25 M). Most known antimalarials were identified in this screen, thus validating our approach. In addition, we identified many novel chemical scaffolds, which likely act through both known and novel pathways. We further show that in some cases the mechanism of action of these antimalarials can be determined by in silico compound activity profiling. This method uses large datasets from unrelated cellular and biochemical screens and the guilt-by-association principle to predict which cellular pathway and/or protein target is being inhibited by select compounds. In addition, the screening method has the potential to provide the malaria community with many new starting points for the development of biological probes and drugs with novel antiparasitic activities.antifolates ͉ cheminformatics ͉ high-throughput screening ͉ Plasmodium falciparum

Insufficient pancreatic β-cell mass or function results in diabetes mellitus. While significant progress has been made in regulating insulin secretion from β-cells in diabetic patients, no pharmacological agents have been described that increase β-cell replication in humans. Here we report aminopyrazine compounds that stimulate robust β-cell proliferation in adult primary islets, most likely as a result of combined inhibition of DYRK1A and GSK3B. Aminopyrazine-treated human islets retain functionality in vitro and after transplantation into diabetic mice. Oral dosing of these compounds in diabetic mice induces β-cell proliferation, increases β-cell mass and insulin content, and improves glycaemic control. Biochemical, genetic and cell biology data point to Dyrk1a as the key molecular target. This study supports the feasibility of treating diabetes with an oral therapy to restore β-cell mass, and highlights a tractable pathway for future drug discovery efforts.

Chemotherapies are known often to induce severe gastrointestinal tract toxicity but the underlying mechanism remains unclear. This study considers the widely applied cytotoxic agent irinotecan (CPT-11) as a representative agent and demonstrates that treatment induces massive release of double-strand DNA from the intestine that accounts for the dose-limiting intestinal toxicity of the compound. Specifically, "self-DNA" released through exosome secretion enters the cytosol of innate immune cells and activates the AIM2 (absent in melanoma 2) inflammasome. This leads to mature IL-1β and IL-18 secretion and induces intestinal mucositis and late-onset diarrhoea. Interestingly, abrogation of AIM2 signalling, either in AIM2-deficient mice or by a pharmacological inhibitor such as thalidomide, significantly reduces the incidence of drug-induced diarrhoea without affecting the anticancer efficacy of CPT-11. These findings provide mechanistic insights into how chemotherapy triggers innate immune responses causing intestinal toxicity, and reveal new chemotherapy regimens that maintain anti-tumour effects but circumvent the associated adverse inflammatory response.

Rapid quantitative methods for characterizing small molecules, peptides, proteins, or RNAs in a broad array of cellular assays would allow one to discover new biological activities associated with these molecules and also provide a more comprehensive profile of drug candidates early in the drug development process. Here we describe a robotic system, termed the automated compound profiler, capable of both propagating a large number of cell lines in parallel and assaying large collections of molecules simultaneously against a matrix of cellular assays in a highly reproducible manner. To illustrate its utility, we have characterized a set of 1,400 kinase inhibitors in a panel of 35 activated tyrosine-kinasedependent cellular assays in dose-response format in a single experiment. Analysis of the resulting multidimensional dataset revealed subclusters of both inhibitors and kinases with closely correlated activities. The approach also identified activities for the p38 inhibitor BIRB796 and the dual src͞abl inhibitor BMS-354825 and exposed the expected side activities for Glivec͞STI571, including cellular inhibition of c-kit and platelet-derived growth factor receptor. This methodology provides a powerful tool for unraveling the cellular biology and molecular pharmacology of both naturally occurring and synthetic chemical diversity.drug discovery ͉ high-throughput screening ͉ tyrosine kinase T he ability to simultaneously interrogate the activities of a library of molecules against a large panel of cellular assays would provide a rapid efficient means to begin to characterize and correlate the biological properties of both natural and synthetic chemical diversity. For example, libraries of noncoding RNAs, mutant growth factors, small molecule kinase inhibitors, or even existing drugs could be assayed for their potency and selectivity in pathway-based or receptor screens or toxicity and metabolic stability in diverse cell types to discover a new biological activity or optimize the pharmacological properties of a molecule (1-3). Although whole-cell systems represent an attractive milieu to characterize gene and small-molecule function, no robust and systematic method exists to correlate chemical structure and biological activity across a large number of molecules and cellular assays. To address this problem, we have developed an approach that affords rapid cost-effective broad-based cellular profiling in parallel against molecular libraries. An industrial-scale automated compound profiling (ACP) system has been designed, which consists of an automated tissue culture system for propagating cell lines, integrated with a system for automatically performing miniaturized cell-based assays in 384-or 1,536-well microplates. The ACP can rapidly test thousands of arrayed molecules, in replicates, in doseresponse format against hundreds of unique cellular assays in a single experiment.To demonstrate this capability, we focused on the problem of identifying selective small-molecule inhibitors of protein tyrosine kinases. Tyrosine ...

Uncontrolled immune responses to intracellular DNA have been shown to induce autoimmune diseases. Homeostasis regulation of immune responses to cytosolic DNA is critical for limiting the risk of autoimmunity and survival of the host. Here, we report that the E3 ubiquitin ligase tripartite motif protein 30α (TRIM30α) was induced by herpes simplex virus type 1 (HSV-1) infection in dendritic cells (DCs). Knockdown or genetic ablation of TRIM30α augmented the type I IFNs and interleukin-6 response to intracellular DNA and DNA viruses. Trim30α-deficient mice were more resistant to infection by DNA viruses. Biochemical analyses showed that TRIM30α interacted with the stimulator of interferon genes (STING), which is a critical regulator of the DNA-sensing response. Overexpression of TRIM30α promoted the degradation of STING via K48-linked ubiquitination at Lys275 through a proteasome-dependent pathway. These findings indicate that E3 ligase TRIM30α is an important negative-feedback regulator of innate immune responses to DNA viruses by targeting STING.

BackgroundGrowing evidence has shown that alterations in gut microbiota composition are associated with multiple autoimmune diseases (ADs). However, it is unclear whether these associations reflect a causal relationship.ObjectiveTo reveal the causal association between gut microbiota and AD, we conducted a two-sample Mendelian randomization (MR) analysis.Materials and MethodsWe assessed genome-wide association study (GWAS) summary statistics for gut microbiota and six common ADs, namely, systemic lupus erythematosus, rheumatoid arthritis, inflammatory bowel disease, multiple sclerosis, type 1 diabetes (T1D), and celiac disease (CeD), from published GWASs. Two-sample MR analyses were first performed to identify causal bacterial taxa for ADs in discovery samples. Significant bacterial taxa were further replicated in independent replication outcome samples. A series of sensitivity analyses was performed to validate the robustness of the results. Finally, a reverse MR analysis was performed to evaluate the possibility of reverse causation.ResultsCombining the results from the discovery and replication stages, we identified one causal bacterial genus, Bifidobacterium. A higher relative abundance of the Bifidobacterium genus was associated with a higher risk of T1D [odds ratio (OR): 1.605; 95% CI, 1.339–1.922; PFDR = 4.19 × 10−7] and CeD (OR: 1.401; 95% CI, 1.139–1.722; PFDR = 2.03 × 10−3), respectively. Further sensitivity analyses validated the robustness of the above associations. The results of reverse MR analysis showed no evidence of reverse causality from T1D and CeD to the Bifidobacterium genus.ConclusionThis study implied a causal relationship between the Bifidobacterium genus and T1D and CeD, thus providing novel insights into the gut microbiota-mediated development mechanism of ADs.

Evidence supports the observational associations of gut microbiota with a variety of psychiatric disorders, but the causal nature of such associations remains obscure. Aiming to comprehensively investigate their causal relationship and to identify specific causal microbe taxa for psychiatric diseases, we conducted a two-sample Mendelian randomization (MR) analysis of gut microbiome with 15 psychiatric diseases. Specifically, the microbiome genome-wide association study (GWAS) in 18,473 individuals from the MiBioGen study was used as exposure sample, and the GWAS for 15 psychiatric diseases was used as outcome samples. One-hundred ninety bacterial taxa from six levels were available for analysis. At a multiple-testing corrected significance level (phylum P &lt; 5.56 × 10–3, class P &lt; 3.33 × 10–3, order P &lt; 2.63 × 10–3, family P &lt; 1.67 × 10–3, genus P &lt; 4.90 × 10–4, and species P &lt; 3.33 × 10–3), the following eight causal associations from seven bacterial features (one phylum + three classes + one order + one family + one species) were identified: family Prevotellaceae with autism spectrum disorder (P = 5.31 × 10–4), class Betaproteobacteria with bipolar disorder (P = 1.53 × 10–3), class Actinobacteria with schizophrenia (P = 1.33 × 10–3), class Bacteroidia and order Bacteroidales with Tourette syndrome (P = 2.51 × 10–3 and 2.51 × 10–3), phylum Actinobacteria and class Actinobacteria with extroversion (P = 8.22 × 10–4 and 1.09 × 10–3), and species Clostridium innocuum with neuroticism (P = 8.92 × 10–4). Sensitivity analysis showed no evidence of reverse causality, pleiotropy, and heterogeneity. Our findings offered novel insights into the gut microbiota–mediated development mechanism of psychiatric disorders.

Autoimmune deficiency and destruction in either βcell mass or function can cause insufficient insulin levels and, as a result, hyperglycemia and diabetes. Thus, promoting β-cell proliferation could be one approach toward diabetes intervention. In this report we describe the discovery of a potent and selective DYRK1A inhibitor GNF2133, which was identified through optimization of a 6-azaindole screening hit. In vitro, GNF2133 is able to proliferate both rodent and human β-cells. In vivo, GNF2133 demonstrated significant dose-dependent glucose disposal capacity and insulin secretion in response to glucosepotentiated arginine-induced insulin secretion (GPAIS) challenge in rat insulin promoter and diphtheria toxin A (RIP-DTA) mice. The work described here provides new avenues to disease altering therapeutic interventions in the treatment of type 1 diabetes (T1D).