Target For Modulation Research Articles

Natural Products with Potential for the Treatment of Pain: Global Evidence from the NAPRALERT Database.

Natural products (NPs) continue to inform the discovery and development of a diversity of drugs, both marketed and investigational. Pain, one of the most common of human experiences and profound challenges in medicine and biology, has emerged at the core of an urgent societal problem, in the United States and globally. The present study employs a retrospective analysis of an extensive set of published literature curated in the NAPRALERT database to identify NPs with experimental evidence of bioactivity supporting the selection and prioritization of NP leads with promise in pain management. The NAPRALERT pain data set currently documents >38,000 pain-relevant experiments reported in >1,750 distinct journals. The evidence presented here was annotated from >10,000 distinct scientific publications identifying NP extracts and isolates with experimental biological data indicating positive mitigation of pain, inflammation, and/or modulation of nociceptive signaling targets. Correlation of ethnomedical uses with experimental data represents a value-added approach to the selection and prioritization of leads. Dissemination of this unique NP/pain data set, with experimental data and information applicable to basic, translational, and clinical science stakeholders alike, furnishes practical evidence in support of a rational selection of NPs for directed pain research. A large portion of the NAPRALERT pain-relevant data set, along with a set of query tools designed to assist user-directed selection and prioritization of leads, are presented as Supporting Information in order to mitigate the limitations inherent in presenting such a large data set in (print) format. To support user efforts, this report involves explication of NAPRALERT data organization and the articulation of rational approaches to user-guided selection of evidence-based NP leads.

Temporal trends and regional differences of initial oral antiarrhythmic drug options in patients with new-onset atrial fibrillation: a report from the GLORIA-AF registry

Abstract Background New-onset atrial fibrillation (AF) is common and antiarrhythmic drugs (AADs) are commonly used for treating such patients. However, whether there are temporal changes and regional differences in the choice of AADs in direct acting non-vitamin K oral anticoagulants (DOACs) era is less studied. Purpose The present study aimed to analyze the temporal trends and regional differences of initial oral AAD options in patients with new-onset AF in the GLORIA-AF registry, based on a proposed modernized classification of AADs in 2018 (Circulation, 2018, PMID: 30354657). AADs involved in the present study included traditional Vaughn-Williams Class I to Class IV AAD, Class IId AAD (digoxin), and Class VII AAD, which acts on the upstream of arrhythmia including angiotensin converting enzyme inhibition, angiotensin receptor blocker, and stains. Methods Temporal changes regarding the AAD use between the two phases of GLORIA-AF and regional differences of AADs choice were investigated. Factors associated with the choice of different AADs were established by multivariate logistic regression. Results Among the 36,617 participants in the GLORIA-AF registry, 33,208 (90.7%) were prescribed with AADs: 74.0% were rate control and 10.2% were rhythm control, and among the prescribed AADs, single and dual AADs were used in 73.3% and 24.9%, respectively. Moreover, 70.5% patients received upstream target modulators (Class VII AAD). Class IIa AADs (beta-blockers) were the most commonly prescribed AAD and slightly increased from Phase II (60.58%) to Phase III (62.91%) while the use of Class IId AAD (e.g. digoxin) decreased regardless of single or combined use. AADs use varied significantly among regions but the temporal trends and regional differences were similar with that of the overall cohort. Age, gender, comorbidities, admission signs, region, and concomitant medications (e.g. anticoagulants) were associated with the choices of different AADs. Conclusions In the DOAC era, new-onset AF patients receiving AAD commonly included upstream therapy. Rate control was still the dominant strategy for patients with new-onset AF but the use of Class IId AAD significantly decreased with the increased use of Class IIa AAD. The choice of AADs demonstrated significant regional differences and concomitant anticoagulants played important roles.Temporal trends in GLORIA-AFComparisons of AADs use in GLORIA-AF

Deciphering farnesol's anti-arthritic and immunomodulatory potential by targeting multiple pathways: a combination of network pharmacology guided exploration and experimental verification.

Farnesol (FAR), a sesquiterpene alcohol, has documented FAR's anti-inflammatory and antioxidant activities. Current study was undertaken to assess the efficacy and mechanism of FAR in arthritis by employing network pharmacology and experimental models. Two experimental models comprising formaldehyde- and complete Freund's adjuvant (CFA)-induced arthritis evaluated the efficacy of FAR in treating arthritis. Various parameters were assessed. Then, a network pharmacology approach was applied to gain further insight into the potential mechanism and signaling pathways. FAR significantly reduced paw volume and the arthritic score and improved the hematological and biochemical changes. Radiographic and histological examination showed the anti-arthritic efficacy of FAR, which was associated with down-regulation of pro-inflammatory mediators and upregulation of anti-inflammatory mediators. Network pharmacology analysis revealed that FAR may exert its anti-arthritic effects by targeting specific genes associated with arthritis. Pathway analysis revealed the involvement of three key signaling pathways (IL-17 signaling, TNF signaling, and toll-like receptor signaling) in the development and progression of arthritis. The results pointed out the protective attributes of farnesol against formaldehyde and CFA-induced arthritis via modulation of multiple targets. This study provides a valuable reference for the development of a new treatment or complementary therapy for arthritis.

Inhibitory Effects of Reynoutria japonica Houtt. on Pain and Cartilage Breakdown in Osteoarthritis Based on Its Multifaceted Anti-Inflammatory Activity: An In Vivo and In Vitro Approach.

In the past 30 years, the number of years lived with disability due to osteoarthritis (OA) has doubled, making it an increasing global health burden. To address this issue, interventions that inhibit the progressive pathology driven by age-related low-grade inflammation, the primary mechanism of OA, are being actively pursued. Recent investigations have focused on modulating the age-related low-grade inflammatory pathology of this disease as a therapeutic target. However, no agent has successfully halted the disease's progression or reversed its irreversible course. Reynoutria japonica Houtt. (RJ), a promising East Asian herbal medicine, has been utilized for several diseases due to its potent anti-inflammatory activity. This study aims to determine RJ's capacity to inhibit OA symptoms and associated inflammation, exploring its potential for further development. In vivo and in vitro experiments demonstrated RJ's anti-OA activity and modulation of multifaceted inflammatory targets. RJ significantly inhibited pain, gait deterioration, and cartilage destruction in a monosodium iodoacetate-induced OA rat model, with its analgesic effect further confirmed in an acetic acid-induced writhing model. RJ exhibited consistent anti-inflammatory activity against multiple targets in serum and cartilage of the OA rat model and lipopolysaccharide-induced RAW 264.7 cells. The inhibition of inflammatory cytokines, including interleukin-1β, interleukin-6, matrix metalloproteinase-13, tumor necrosis factor-α, and nitric oxide synthase 2, suggests that RJ's alleviation of OA manifestations relates to its multifaceted anti-inflammatory activity. These results indicate that RJ merits further investigation as a disease-modifying drug candidate targeting OA's inflammatory pathology. To further characterize the pharmacological properties of RJ, future studies with expanded designs are warranted.

The Metformin Immunoregulatory Actions in Tumor Suppression and Normal Tissues Protection.

The immune system is the key player in a wide range of responses in normal tissues and tumors to anticancer therapy. Inflammatory and fibrotic responses in normal tissues are the main limitations of chemotherapy, radiotherapy, and also some newer anticancer drugs such as immune checkpoint inhibitors (ICIs). Immune system responses within solid tumors including anti-tumor and tumor-promoting responses can suppress or help tumor growth. Thus, modulation of immune cells and their secretions such as cytokines, growth factors and epigenetic modulators, pro-apoptosis molecules, and some other molecules can be suggested to alleviate side effects in normal tissues and drug-resistance mechanisms in the tumor. Metformin as an anti-diabetes drug has shown intriguing properties such as anti-inflammation, anti-fibrosis, and anticancer effects. Some investigations have uncovered that metformin can ameliorate radiation/chemotherapy toxicity in normal cells and tissues through the modulation of several targets in cells and tissues. These effects of metformin may ameliorate severe inflammatory responses and fibrosis after exposure to ionizing radiation or following treatment with highly toxic chemotherapy drugs. Metformin can suppress the activity of immunosuppressive cells in the tumor through the phosphorylation of AMP-activated protein kinase (AMPK). In addition, metformin may stimulate antigen presentation and maturation of anticancer immune cells, which lead to the induction of anticancer immunity in the tumor. This review aims to explain the detailed mechanisms of normal tissue sparing and tumor suppression during cancer therapy using adjuvant metformin with an emphasis on immune system responses.

Targeting modulation of intestinal flora through oral route by an antimicrobial nucleic acid-loaded exosome-like nanovesicles to improve Parkinson’s disease

Parkinson’s disease (PD) is one of the most prevalent neurodegenerative diseases. It is usually accompanied by motor and non-motor symptoms that seriously threaten the health and the quality of life. Novel medications are urgently needed because current pharmaceuticals can relieve symptoms but cannot stop disease progression. The microbiota-gut-brain axis (MGBA) is closely associated with the occurrence and development of PD and is an effective therapeutic target. Tetrahedral framework nucleic acids (tFNAs) can modulate the microbiome and immune regulation. However, such nucleic acid nanostructures are very sensitive to acids which hinders this promising approach. Therefore, we prepared exosome-like nanovesicles (Exo@tac) from ginger that are acid resistant and equipped with tFNAs modified by antimicrobial peptides (AMP). We verified that Exo@tac regulates intestinal bacteria associated with the microbial-gut-brain axis in vitro and significantly improves PD symptoms in vivo when administered orally. Microbiota profiling confirmed that Exo@tac normalizes the intestinal flora composition of mouse models of PD. Our findings present a novel strategy for the development of PD drugs and the innovative delivery of nucleic acid nanomedicines.

Transcriptome analysis of the coexpression network of genes related to antioxidant characteristics after grain filling in purple rice

Antioxidant capacity is an important indicator for evaluating the growth and developmental quality of rice. This study has guiding significance for the cultivation of high-nutrient-value varieties. To investigate the molecular mechanisms underlying the antioxidant characteristics of rice grains after the filling stage, Yangzinuo 1 (YZN1) was used as the experimental material, and grains collected at five different time points (7 days apart) after the filling stage were used for transcriptome sequencing. Through weighted gene coexpression network analysis (WGCNA), a coexpression network of gene weights related to antioxidant characteristics was constructed. LOC_Os10g39140, LOC_Os10g38276, and LOC_Os05g45740 were identified from the 2 modules showing the highest correlations with the target traits. GO functional annotation showed that target modules were enriched in pathways related to phenylalanine, flavonoids, and other related pathways, such as GO:0006558, GO:0006559, GO:0009812, and GO:0009813. Correlation analysis with metabolites revealed that differentially expressed genes were significantly enriched in pathways related to antioxidant characteristics and energy metabolism processes, such as glycolysis/gluconeogenesis and flavonoid biosynthesis. The core genes identified in this study were found to be highly correlated with antioxidant characteristics and enriched in pathways related to metabolic and energy pathways and molecular activities. These results provide an effective dataset supporting breeding targeting functional rice characteristics.

The Therapeutic Potential of Targeting Tumor Microenvironment and Modulation of Immunotherapy in Gastrointestinal Cancer.

Immunotherapy, as a novel treatment approach for various disorders, including cancers, is designed to either stimulate or suppress the immune system with high speci-ficity. The recent achievements of this therapy in clinical trials are set to transform tradi-tional treatment methods. Furthermore, it holds promise for enhancing the survival rates of patients suffering from both metastatic cancers and primary stages. Gastrointestinal Cancers (GI) account for 26% of global incidence and 35% of worldwide deaths. Treat-ment can be carried out using targeted immunotherapy in these cancers. If the tiers are superior, improvement could require more enterprise. On account that the function of immunotherapy in GI has been so promising, solely in sufferers with severe metastatic levels, within the literature, the immune checkpoint inhibitors in cancer immunotherapy of GI cancers, chimeric antigen receptor T-cell (vehicle-T), modulators of the tumor mi-croenvironment, and drug resistance mechanisms in immunotherapy as an effective treatment approach to GI cancers along with colon, pancreas, gastric, and esophageal cancers have been addressed. This review provides an overview of FDA-approved im-munotherapy drugs and ongoing preclinical developments. Additionally, we offer in-sights into the future of immunotherapy for GI cancer patients, addressing the associated challenges.

The Barnase-Barstar-based pre-targeting strategy for enhanced antitumor therapy in vivo

There is a great need for novel approaches to the treatment of epithelial ovarian carcinoma, which is the leading cause of mortality from gynecological malignancies. In this study, the pre-targeting technology was used to enhance the in vivo targeting of cytotoxic module composed of nanoliposomes loaded with a truncated form of Pseudomonas aeruginosa exotoxin A (PE40) to cancer cells. Pre-targeting system used in this study is composed of bacterial ribonuclease Barnase and its natural antitoxin Barstar. Barstar, genetically fused to various engineered scaffold proteins specific to tumor-associated antigens (HER2, EpCAM) serves as a primary module for precise cancer cell recognition. Barnase conjugated to a therapeutic agent serves as a cytotoxic or secondary module for malignant cell elimination. Due to strong non-covalent interaction (KD10−14 M) of Barstar and Barnase, the primary and secondary modules efficiently interact with each other on the cell surface, which has been proven by confocal microscopy and flow cytometry. Using mice with SKOV-3 ovarian cancer xenografts, we have shown that regardless of the targeting module, the pre-targeting approach is much more effective than a single-step active targeting.

Dysfunction of the NMDA Receptor in the Pathophysiology of Schizophrenia and/or the Pathomechanisms of Treatment-Resistant Schizophrenia.

For several decades, the dopamine hypothesis contributed to the discovery of numerous typical and atypical antipsychotics and was the sole hypothesis for the pathophysiology of schizophrenia. However, neither typical nor atypical antipsychotics, other than clozapine, have been effective in addressing negative symptoms and cognitive impairments, which are indices for the prognostic and disability outcomes of schizophrenia. Following the development of atypical antipsychotics, the therapeutic targets for antipsychotics expanded beyond the blockade of dopamine D2 and serotonin 5-HT2A receptors to explore the partial agonism of the D2 receptor and the modulation of new targets, such as D3, 5-HT1A, 5-HT7, and metabotropic glutamate receptors. Despite these efforts, to date, psychiatry has not successfully developed antipsychotics with antipsychotic properties proven to be superior to those of clozapine. The glutamate hypothesis, another hypothesis regarding the pathophysiology/pathomechanism of schizophrenia, was proposed based on clinical findings that N-methyl-D-aspartate glutamate receptor (NMDAR) antagonists, such as phencyclidine and ketamine, induce schizophrenia-like psychotic episodes. Large-scale genome-wide association studies (GWASs) revealed that approximately 30% of the risk genes for schizophrenia (the total number was over one hundred) encode proteins associated with glutamatergic transmission. These findings supported the validation of the glutamate hypothesis, which was inspired by the clinical findings regarding NMDAR antagonists. Additionally, these clinical and genetic findings suggest that schizophrenia is possibly a syndrome with complicated pathomechanisms that are affected by multiple biological and genetic vulnerabilities. The glutamate hypothesis has been the most extensively investigated pathophysiology/pathomechanism hypothesis, other than the dopamine hypothesis. Studies have revealed the possibility that functional abnormalities of the NMDAR play important roles in the pathophysiology/pathomechanism of schizophrenia. However, no antipsychotics derived from the glutamatergic hypothesis have yet been approved for the treatment of schizophrenia or treatment-resistant schizophrenia. Considering the increasing evidence supporting the potential pro-cognitive effects of glutamatergic agents and the lack of sufficient medications to treat the cognitive impairments associated with schizophrenia, these previous setbacks cannot preclude research into potential novel glutamate modulators. Given this background, to emphasize the importance of the dysfunction of the NMDAR in the pathomechanism and/or pathophysiology of schizophrenia, this review introduces the increasing findings on the functional abnormalities in glutamatergic transmission associated with the NMDAR.

A Method of Ship Target Modulation Feature Enhancement Based on Phase Information

Abstract Ship modulation features are commonly used in underwater acoustic target recognition, which contains propeller parameter information of the target. The basis processing of modulation spectrum is demodulation. Traditional envelope demodulation methods only consider amplitude information and make little use of phase information, which can fully characterize the dynamic characteristics of radiated noise. In this paper, a modulation feature enhancement method based on phase information is proposed, which takes full account of the phase information of the target signal. It uses the modified group delay function to demodulate the target signal, and utilizes the phase stability characteristics of the modulated line spectrum to enhance the modulation features of the ship target by weighted phase features. Simulation and sea trial data verification show that the proposed method can effectively enhance the energy of the line spectrum, suppress the background noise, and improve the signal-to-noise ratio of the modulation line spectrum, which lays a good foundation for further using the modulation line spectrum to carry out the estimation of modulation parameters, and has a good application prospect in the field of underwater acoustic target recognition.

A Novel Confocal Scanning Protein-Protein Interaction Assay (PPI-CONA) Reveals Exceptional Selectivity and Specificity of CC0651, a Small Molecule Binding Enhancer of the Weak Interaction between the E2 Ubiquitin-Conjugating Enzyme CDC34A and Ubiquitin.

Protein-protein interactions (PPIs) are some of the most challenging target classes in drug discovery. Highly sensitive detection techniques are required for the identification of chemical modulators of PPIs. Here, we introduce PPI confocal nanoscanning (PPI-CONA), a miniaturized, microbead based high-resolution fluorescence imaging assay. We demonstrate the capabilities of PPI-CONA by detecting low affinity ternary complex formation between the human CDC34A ubiquitin-conjugating (E2) enzyme, ubiquitin, and CC0651, a small molecule enhancer of the CDC34A-ubiquitin interaction. We further exemplify PPI-CONA with an E2 enzyme binding study on CC0651 and a CDC34A binding specificity study of a series of CC0651 analogues. Our results indicate that CC0651 is highly selective toward CDC34A. We further demonstrate how PPI-CONA can be applied to screening very low affinity interactions. PPI-CONA holds potential for high-throughput screening for modulators of PPI targets and characterization of their affinity, specificity, and selectivity.

Discovery of potent SARS-CoV-2 nsp3 macrodomain inhibitors uncovers lack of translation to cellular antiviral response.

A strategy for pandemic preparedness is the development of antivirals against a wide set of viral targets with complementary mechanisms of action. SARS-CoV-2 nsp3-mac1 is a viral macrodomain with ADP-ribosylhydrolase activity, which counteracts host immune response. Targeting the virus' immunomodulatory functionality offers a differentiated strategy to inhibit SARS-CoV-2 compared to approved therapeutics, which target viral replication directly. Here we report a fragment-based lead generation campaign guided by computational approaches. We discover tool compounds which inhibit nsp3-mac1 activity at low nanomolar concentrations, and with responsive structure-activity relationships, high selectivity, and drug-like properties. Using our inhibitors, we show that inhibition of nsp3-mac1 increases ADP-ribosylation, but surprisingly does not translate to demonstrable antiviral activity in cell culture and iPSC-derived pneumocyte models. Further, no synergistic activity is observed in combination with interferon gamma, a main protease inhibitor, nor a papain-like protease inhibitor. Our results question the extent to which targeting modulation of innate immunity-driven ADP-ribosylation can influence SARS-CoV-2 replication. Moreover, these findings suggest that nsp3-mac1 might not be a suitable target for antiviral therapeutics development.

Drug Repurposing for COVID-19 by Constructing a Comorbidity Network with Central Nervous System Disorders.

In the post-COVID-19 era, treatment options for potential SARS-CoV-2 outbreaks remain limited. An increased incidence of central nervous system (CNS) disorders has been observed in long-term COVID-19 patients. Understanding the shared molecular mechanisms between these conditions may provide new insights for developing effective therapies. This study developed an integrative drug-repurposing framework for COVID-19, leveraging comorbidity data with CNS disorders, network-based modular analysis, and dynamic perturbation analysis to identify potential drug targets and candidates against SARS-CoV-2. We constructed a comorbidity network based on the literature and data collection, including COVID-19-related proteins and genes associated with Alzheimer's disease, Parkinson's disease, multiple sclerosis, and autism spectrum disorder. Functional module detection and annotation identified a module primarily involved in protein synthesis as a key target module, utilizing connectivity map drug perturbation data. Through the construction of a weighted drug-target network and dynamic network-based drug-repurposing analysis, ubiquitin-carboxy-terminal hydrolase L1 emerged as a potential drug target. Molecular dynamics simulations suggested pregnenolone and BRD-K87426499 as two drug candidates for COVID-19. This study introduces a dynamic-perturbation-network-based drug-repurposing approach to identify COVID-19 drug targets and candidates by incorporating the comorbidity conditions of CNS disorders.

Targeted degradation of undruggable proteins using a novel heterobifunctional proteomimetic platform.

47 Background: Of the ~20,000 proteins in the human genome, only a subset can be modulated via traditional pharmacological approaches. “Undruggable” targets currently include proteins with pivotal roles in cancer pathogenesis. Our work aims to introduce a new paradigm for engaging these clinically relevant proteins using a modular platform we term the HYbrid DegRAding Copolymers (HYDRACs). HYDRACs multiplex targeting warheads with degradation inducers and have long circulation times plus high cell uptake. Preliminary studies on MYC and RAS, targets of great pharmaceutical interest, highlight the potential of this platform to revolutionize drug design. Methods: HYDRACs containing MYC or RAS targeting peptides randomly copolymerized with degrons were synthesized using ROMP. Fluorescent and biotin-tags were incorporated for use in uptake and pull-down assays. Viability following treatment with MYC-HYDRACs was performed in multiple cell lines with both cellular (MYC-independent lines) and polymer composition controls. Target engagement was assessed via immunoprecipitation and circular dichroism with protein degradation monitored by WB. Unbiased whole proteome analysis and RNAseq were done to confirm observed effects were selectively on-target. In vivo efficacy and biodistribution was assessed in tumor-bearing mice. Results: HYDRACs show high levels of cell uptake and antiproliferative effects at sub-micromolar concentrations in a formulation- and target-dependent manner. Cells treated with MYC-HYDRACs displayed reduced MYC protein levels, which were rescued by proteasome or neddylation inhibition. Swapping out the degron for various validated E3 ligase recruiters maintained MYC degradation, highlighting the “plug-and-play” nature of this approach. On-target activity was confirmed via RNAseq. Biophysical analysis showed strong HYDRAC-protein interactions, orthogonally supported by the presence of target protein following pull-down of biotin-terminated HYDRACs. Target protein degradation only occurred following treatment with an intact HYDRAC compound. Mice bearing MYC-CaP tumors showed delayed tumor growth following treatment with MYC-HYDRACs, with compound accumulation in the tumor for up to 72 h following a single injection. Generalizability was demonstrated against RAS, with RAS-HYDRACs capable of degrading KRAS across multiple different alleles, acting as a pan-KRAS degrader. Conclusions: We present a novel platform technology that addresses the challenges inherent to peptide delivery approaches. HYDRACs have the potential to dramatically alter the drug discovery landscape, allowing for the development of cancer-relevant target modulators for which there are no current viable therapies. We envision the HYDRAC platform as a generalizable approach to designing degraders of proteins of interest, greatly expanding the therapeutic armamentarium for TPD.

Network Pharmacology, Molecular Docking and in vivo-based Analysis on the Effects of the MBZM-N-IBT for Arthritis.

Arthritis is the cause of morbidity associated with Chikungunya virus (CHIKV) infection. It persists even after the virus has been cleared from the body. MBZM-NIBT was earlier shown to inhibit (CHIKV) infection in vitro and in vivo. The objective of this study is to determine the ability of MBZM-N-IBT to manage arthritis independent of CHIKV infection. The acute toxicity of MBZM-N-IBT was determined to find a permissible oral dose. Effects against inflammation and arthritis were determined in relevant preclinical models. Network pharmacology was used to propose possible modes of action. It showed no acute toxicity orally, with an estimated LD50 of more than 5000 mg/kg in rats. It significantly reduced inflammation. Its effect against Complete Freund's Adjuvant (CFA) induced arthritis was comparable to that of Diclofenac sodium. Network pharmacology analysis revealed that MBZM-N-IBT can potentially interfere with multiple targets and pathways. MMP12 and CTSD were found to be the most probable hub targets of MBZM-N-IBT for its effect against arthritis. In conclusion, MBZM-N-IBT is safe at 50 mg/kg and can manage arthritis independent of CHIKV infection through modulation of multiple pathways and arthritis-associated targets.

Cholesterol-dependent dynamic changes in the conformation of the type 1 cholecystokinin receptor affect ligand binding and G protein coupling.

Development of optimal therapeutics for disease states that can be associated with increased membrane cholesterol requires better molecular understanding of lipid modulation of the drug target. Type 1 cholecystokinin receptor (CCK1R) agonist actions are affected by increased membrane cholesterol, enhancing ligand binding and reducing calcium signaling, while agonist actions of the closely related CCK2R are not. In this work, we identified a set of chimeric human CCK1R/CCK2R mutations that exchange the cholesterol sensitivity of these 2 receptors, providing powerful tools when expressed in CHO and HEK-293 model cell lines to explore mechanisms. Static, low energy, high-resolution structures of the mutant CCK1R constructs, stabilized in complex with G protein, were not substantially different, suggesting that alterations to receptor dynamics were key to altered function. We reveal that cholesterol-dependent dynamic changes in the conformation of the helical bundle of CCK receptors affects both ligand binding at the extracellular surface and G protein coupling at the cytosolic surface, as well as their interrelationships involved in stimulus-response coupling. This provides an ideal setting for potential allosteric modulators to correct the negative impact of membrane cholesterol on CCK1R.

Sex Differences Affect the NRF2 Signaling Pathway in the Early Phase of Liver Steatosis: A High-Fat-Diet-Fed Rat Model Supplemented with Liquid Fructose.

Sex differences may play a role in the etiopathogenesis and severity of metabolic dysfunction-associated steatotic liver disease (MASLD), a disorder characterized by excessive fat accumulation associated with increased inflammation and oxidative stress. We previously observed the development of steatosis specifically in female rats fed a high-fat diet enriched with liquid fructose (HFHFr) for 12 weeks. The aim of this study was to better characterize the observed sex differences by focusing on the antioxidant and cytoprotective pathways related to the KEAP1/NRF2 axis. The KEAP1/NRF2 signaling pathway, autophagy process (LC3B and LAMP2), and endoplasmic reticulum stress response (XBP1) were analyzed in liver homogenates in male and female rats that were fed a 12-week HFHFr diet. In females, the HFHFr diet resulted in the initial activation of the KEAP1/NRF2 pathway, which was not followed by the modulation of downstream molecular targets; this was possibly due to the increase in KEAP1 levels preventing the nuclear translocation of NRF2 despite its cytosolic increase. Interestingly, while in both sexes the HFHFr diet resulted in an increase in the levels of LC3BII/LC3BI, a marker of autophagosome formation, only males showed a significant upregulation of LAMP2 and XBP1s; this did not occur in females, suggesting impaired autophagic flux in this sex. Overall, our results suggest that males are characterized by a greater ability to cope with an HFHFr metabolic stimulus mainly through an autophagic-mediated proteostatic process while in females, this is impaired. This might depend at least in part upon the fine modulation of the cytoprotective and antioxidant KEAP1/NRF2 pathway resulting in sex differences in the occurrence and severity of MASLD. These results should be considered to design effective therapeutics for MASLD.

Comparative Transcriptome Analysis of the Hypothalamic-Pituitary-Gonadal Axis of Jinhu Grouper (Epinephelus fuscoguttatus ♀ × Epinephelus tukula ♂) and Tiger Grouper (Epinephelus fuscoguttatus).

Jinhu groupers, the hybrid offspring of tiger groupers (Epinephelus fuscoguttatus) and potato groupers (Epinephelus tukula), have excellent heterosis in fast growth and strong stress resistance. However, compared with the maternal tiger grouper, Jinhu groupers show delayed gonadal development. To explore the interspecific difference in gonadal development, we compared the transcriptomes of brain, pituitary, and gonadal tissues between Jinhu groupers and tiger groupers at 24-months old. In total, 3034 differentially expressed genes (DEGs) were obtained. KEGG (Kyoto Encyclopedia of Genes and Genomes) enrichment analyses showed that the osteoclast differentiation, oocyte meiosis, and ovarian steroidogenesis may be involved in the difference in gonadal development. Trend analysis showed that the DEGs were mainly related to signal transduction and cell growth and death. Additionally, differences in expression levels of nr4a1, pgr, dmrta2, tbx19, and cyp19a1 may be related to gonadal retardation in Jinhu groupers. A weighted gene co-expression network analysis revealed three modules (i.e., saddlebrown, paleturquoise, and greenyellow) that were significantly related to gonadal development in the brain, pituitary, and gonadal tissues, respectively, of Jinhu groupers and tiger groupers. Network diagrams of the target modules were constructed and the respective hub genes were determined (i.e., cdh6, col18a1, and hat1). This study provides additional insight into the molecular mechanism underlying ovarian stunting in grouper hybrids.

Integrating bacterial molecular genetics with chemical biology for renewed antibacterial drug discovery.

The application of dyes to understanding the aetiology of infection inspired antimicrobial chemotherapy and the first wave of antibacterial drugs. The second wave of antibacterial drug discovery was driven by rapid discovery of natural products, now making up 69% of current antibacterial drugs. But now with the most prevalent natural products already discovered, ∼107 new soil-dwelling bacterial species must be screened to discover one new class of natural product. Therefore, instead of a third wave of antibacterial drug discovery, there is now a discovery bottleneck. Unlike natural products which are curated by billions of years of microbial antagonism, the vast synthetic chemical space still requires artificial curation through the therapeutics science of antibacterial drugs - a systematic understanding of how small molecules interact with bacterial physiology, effect desired phenotypes, and benefit the host. Bacterial molecular genetics can elucidate pathogen biology relevant to therapeutics development, but it can also be applied directly to understanding mechanisms and liabilities of new chemical agents with new mechanisms of action. Therefore, the next phase of antibacterial drug discovery could be enabled by integrating chemical expertise with systematic dissection of bacterial infection biology. Facing the ambitious endeavour to find new molecules from nature or new-to-nature which cure bacterial infections, the capabilities furnished by modern chemical biology and molecular genetics can be applied to prospecting for chemical modulators of new targets which circumvent prevalent resistance mechanisms.