7196 research outputs found
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Improved resilience and proteostasis mediate longevity upon DAF-2 degradation in old age.
No full textLittle is known about the possibility of reversing age-related biological changes when they have already occurred. To explore this, we have characterized the effects of reducing insulin/IGF-1 signaling (IIS) during old age. Reduction of IIS throughout life slows age-related decline in diverse species, most strikingly in the nematode Caenorhabditis elegans. Here we show that even at advanced ages, auxin-induced degradation of DAF-2 in single tissues, including neurons and the intestine, is still able to markedly increase C. elegans lifespan. We describe how reversibility varies among senescent changes. While senescent pathologies that develop in mid-life were not reversed, there was a rejuvenation of the proteostasis network, manifesting as a restoration of the capacity to eliminate otherwise intractable protein aggregates that accumulate with age. Moreover, resistance to several stressors was restored. These results support several new conclusions. (1) Loss of resilience is not solely a consequence of pathologies that develop in earlier life. (2) Restoration of proteostasis and resilience by inhibiting IIS is a plausible cause of the increase in lifespan. And (3), most interestingly, some aspects of the age-related transition from resilience to frailty can be reversed to a certain extent. This raises the possibility that the effect of IIS and related pathways on resilience and frailty during aging in higher animals might possess some degree of reversibility
Condensin I folds the Caenorhabditis elegans genome.
No full textThe structural maintenance of chromosome (SMC) complexes-cohesin and condensins-are crucial for chromosome separation and compaction during cell division. During the interphase, mammalian cohesins additionally fold the genome into loops and domains. Here we show that, in Caenorhabditis elegans, a species with holocentric chromosomes, condensin I is the primary, long-range loop extruder. The loss of condensin I and its X-specific variant, condensin I, leads to genome-wide decompaction, chromosome mixing and disappearance of X-specific topologically associating domains, while reinforcing fine-scale epigenomic compartments. In addition, condensin I/I inactivation led to the upregulation of X-linked genes and unveiled nuclear bodies grouping together binding sites for the X-targeting loading complex of condensin I. C. elegans condensin I/I thus uniquely organizes holocentric interphase chromosomes, akin to cohesin in mammals, as well as regulates X-chromosome gene expression
Metabolic enzymes and as potential epigenetic regulators during embryogenesis.
No full textThe intersection of metabolic processes and epigenetic regulation during embryogenesis is crucial yet not fully understood. Through a candidate RNAi screen in , we identified metabolic enzymes ALDO-2 and PDHB-1 as potential epigenetic regulators. Mild alteration of the chromatin remodeler LET-418 /Mi2 activity rescues embryonic lethality induced by suppressing or suggesting a critical role for glucose and pyruvate metabolism in chromatin remodeling during embryogenesis. Given the conservation of central metabolic pathways and chromatin modifiers across species, our findings lay the foundation for future mechanistic investigations into the interplay between epigenetics and metabolism during development and upon disease
Highly sensitive LC-MS/MS method for the quantitative analysis of mometasone furoate in human plasma, method validation and application to clinical pharmacokinetic studies
No full textWe report the development and the validation of a sensitive LC-MS/MS method for mometasone furoate (MF) analysis in human plasma. Plasma samples were processed through liquid-liquid extraction and analyzed by LC-MS/MS operating in positive mode using multiple reaction monitoring of transitions m/z 520.9.0 → 355.0 and m/z 525.8 → 355.0 for MF and the internal standard (IS), respectively. Separation was achieved at 1.0 mL/min on a C18 column using a gradient elution of mobile phase of 0.05% ammonia in water (phase A) and acetonitrile (phase B). The linear response range was 0.250 to 100 pg/mL using 1/x2 weighing factor. The intra- and inter-day accuracies (bias %) ranged between -3.1 and 18.9 % and from -2.8 to 16.3 %, respectively. The intra- and inter day precisions (CV %) range from 0.4 to 13.9% and 1.0 – 8.1 %, respectively. The CV (%) of the IS normalized matrix factor (MF) was below 15% and not affected in lipemic and hemolyzed plasmas. MF Normalized recoveries were consistent and reproducible with a CV% value of 6.0. The present method was successfully applied to the quantitative analysis of MF in clinical studies where MF, Indacaterol and Glycopyrronium were delivered as a fixed dose combination
MBL949, a long acting GDF15 receptor agonist, in preclinical and Phase 1 and Phase 2 randomized placebo controlled parallel design clinical trials in healthy volunteers and patients with obesity
No full textBackground: Growth Differentiation Factor 15 (GDF15) is a divergent member of the TGF- superfamily which signals via the hindbrain glial-derived neurotrophic factor (GDNF) receptor alpha-like (GFRAL)-rearranged during transfection (RET) (GFRAL-RET) receptor. In nonclinical species, GDF15 is a potent anorexigen leading to substantial weight loss. MBL949 is a half-life extended recombinant human GDF15 dimer.
Methods: MBL949 was evaluated in nonclinical species and in humans in two randomized and placebo-controlled clinical trials. In the Phase 1 first-in-human, single ascending dose trial MBL949 or placebo was injected subcutaneously to overweight and obese healthy volunteers (n=65) at doses ranging from 0.03 to 20 mg. In the Phase 2 clinical trial, MBL949 or placebo was administered to obese participants (n=126) in five different dose regimens predicted to be efficacious from the Phase 1 trial or placebo, with investigational drug administered subcutaneously every other week for a total of 8 doses.
Results: In nonclinical species, MBL949 was generally safe and effective with reduced food intake and body weight.
observed in mice, rats, dogs, and monkeys. Weight loss was primarily from reduction in fat, and metabolic endpoints were improved. In humans, a single ascending dose study in overweight or obese healthy adults demonstrated mean terminal half-life of 18-22 days, and evidence of weight loss at the higher doses. In the Phase 2 trial, weight loss was minimal following biweekly dosing of MBL949 for 14 weeks. MBL949 was safe and generally tolerated in humans over the dose range tested, adverse events of the gastrointestinal system were the most frequent observed.
Conclusion: The prolonged half-life of MBL949 supports biweekly dosing in patients. MBL949 had an acceptable safety profile. The robust weight loss observed in nonclinical species did not translate to weight loss efficacy in humans
An automatic end-to-end chemical synthesis development platform powered by large language models.
No full textThe rapid emergence of large language model (LLM) technology presents promising opportunities to facilitate the development of synthetic reactions. In this work, we leveraged the power of GPT-4 to build an LLM-based reaction development framework (LLM-RDF) to handle fundamental tasks involved throughout the chemical synthesis development. LLM-RDF comprises six specialized LLM-based agents, including Literature Scouter, Experiment Designer, Hardware Executor, Spectrum Analyzer, Separation Instructor, and Result Interpreter, which are pre-prompted to accomplish the designated tasks. A web application with LLM-RDF as the backend was built to allow chemist users to interact with automated experimental platforms and analyze results via natural language, thus, eliminating the need for coding skills and ensuring accessibility for all chemists. We demonstrated the capabilities of LLM-RDF in guiding the end-to-end synthesis development process for the copper/TEMPO catalyzed aerobic alcohol oxidation to aldehyde reaction, including literature search and information extraction, substrate scope and condition screening, reaction kinetics study, reaction condition optimization, reaction scale-up and product purification. Furthermore, LLM-RDF's broader applicability and versability was validated on various synthesis tasks of three distinct reactions (SNAr reaction, photoredox C-C cross-coupling reaction, and heterogeneous photoelectrochemical reaction)
Development of in vitro biopharmaceutics tools for predicting the bioavailability of subcutaneously injected monoclonal antibodies and oligonucleotides.
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Afpdb – an efficient structure manipulation package for AI protein design
No full textMotivation: The advent of AlphaFold and other protein Artificial Intelligence (AI) models has transformed protein design. To maximize the likelihood of success, the AI-driven protein design process can create thousands of design candidates. A typical AI design workflow involves handling large-scale structure file read/write operations, performing structure alignment, measuring deviations, standardizing chain/residue labels, extracting residues, identifying mutations, and automating visualization generations. Existing programming packages fall short of meeting these new requirements. To address this gap, we developed the Afpdb package.
Results: The Afpdb package, built upon AlphaFold’s NumPy architecture, significantly accelerates protein structure computations. Leveraging the intuitive contig syntax proposed by RFDiffusion, Afpdb streamlines residue and atom selection. Afpdb augments Biopython and other macromolecular structure frameworks with a suite of methods commonly used in protein AI design but are not readily available elsewhere. Additionally, it seamlessly integrates PyMOL’s visualization capabilities. In summary, Afpdb can enhance productivity in universal protein structure manipulation tasks within the structural biology community
A multifaceted approach to understanding protein-buffer interactions in biopharmaceuticals.
No full textThe excipient selection process plays a crucial role in biopharmaceutical formulation development to ensure the long-term stability of the drug product. Though there are numerous options approved by regulatory authorities, only a subset is commonly utilized. Previous research has proposed various stabilization mechanisms, including protein-excipient interactions. However, identifying these interactions remains challenging due to their weak and transient nature. In this study, we present a comprehensive approach to identify such interactions. Using the HT CPMG (Carr-Purcel-Meiboom-Gill) filter experiment we identified interactions of rituximab with certain buffers and amino acids, shedding light on its Fc fragment instability that manifested during the enzymatic cleavage of the antibody. Moreover, chemometric analyses of 2D NMR fingerprints revealed interactions of selected excipients with antibody fragments. Furthermore, molecular dynamics simulations revealed potential interacting hotspots without NMR spectra assignment. Our results highlight the importance of an orthogonal methods approach to uncovering these critical interactions, advancing our understanding of excipient stabilization mechanisms and rational formulation design in biopharmaceutics
Diagnostic potential of genomic blood biomarkers of pulmonary fibrosis in a prospective cohort
No full textFibrotic interstitial lung diseases (ILDs) result from excessive deposition of extracellular matrix (ECM) proteins in the lung, causing irreversible damage to the lung architecture. Clinical management of ILDs differs depending on the diagnosis, but differentiation between subtypes can be difficult and better clinical biomarkers are needed. In this study, we use a 166-gene NanoString assay to investigate whether there are ILD subtype-specific transcripts in whole blood. We identified one transcript, killer cell lectin like receptor 1 (KLRF1), as differentially expressed between idiopathic pulmonary fibrosis (IPF) and systemic sclerosis-associated ILD (SSc-ILD), and identified two transcripts (VCAN, LTK) associated with IPF expression against other ILD subtypes. These findings were validated by examining their expression in ILD lung, with KLRF1 expression significantly higher in SSc-ILD compared to IPF and hypersensitivity pneumonitis (HP) samples. Taken together, this pilot study provides support for the use of the peripheral transcriptome in identifying diagnostic biomarkers of ILD with biological relevance