Pharmacokinetic Modeling of the Effect of Tariquidar on Ondansetron Disposition into the Central Nervous System.

PURPOSE: Serotonin (5-HT3) receptor antagonists are promising agents for treatment of neuropathic pain. However, insufficient drug exposure at the central nervous system (CNS) might result in lack of efficacy. The goal of this study was to evaluate the impact of administration of a Pgp inhibitor (tariquidar) on ondansetron exposure in the brain, spinal cord, and cerebrospinal fluid in a wild-type rat model. METHODS: Ondansetron (10 mg/kg) and tariquidar (7.5 mg/kg) were administered intravenously, plasma and tissue samples were collected and analyzed by HPLC. A mathematical model with brain, spinal cord, cerebrospinal fluid and two systemic disposition compartments was developed to describe the data. RESULTS: The results demonstrate that tariquidar at 7.5 mg/kg resulted in a complete inhibition of Pgp efflux of ondansetron in the brain and spinal cord. The compartmental model successfully captured pharmacokinetics of ondansetron in wild type and Pgp knockout (KO) animals receiving the drug alone or in wild type animals receiving the ondansetron and tariquidar combination. CONCLUSIONS: The study provided important quantitative information on enhancement of CNS exposure to ondansetron using co-administration of Pgp Inhibitor in a rat model, which will be further utilized in conducting a clinical study. Tariquidar co-administration resulted in ondansetron CNS exposure comparable to observed in Pgp KO rats. Results also highlighted the effect of tariquidar on plasma disposition of ondansetron, which may not be dependent on Pgp inhibition, and should be evaluated in future studies.

Effect of activated carbon-based two-stage adsorption on biogenic amine reduction and quality of anchovy fish sauce at industrial scale.

This study was aimed to investigate the effectiveness of activated carbon on reduction in biogenic amines (BAs) via two-stage adsorption process at industrial scale, and the consequent effect was evaluated by the taste and aroma of anchovy fish sauce. Through reaction surface methodology, the optimal working paratmeters were determined to adsorbent composition of 2% activated carbon and 0.9% diatomite under temperature of 27 °C for 97 min. Upon optimized settings at industrial scale, there were effective reductions in tryptamine (by 100%), cadaverine (by 10%), histamine (by 61%), and tyramine (by 96%), while the changes in taste-related amino nitrogen, total nitrogen, free amino acids, and color were minimum. In addition, off-flavor-causing compounds, such as alcohols and acids, were removed by the developed method. From the obtained results, the activated carbon-based two-stage adsorption approach can provide the framework for control of BAs contents in fish-based sauces or stocks at commercial and industrial scales.

Effects of the physical structure and surface charge of activated carbon on the reduction of biogenic amines in anchovy fish sauce.

This study aimed to efficiently reduce a large number of biogenic amines in salt-fermented fish sauce while minimizing sensory reduction using various activated carbons. Aromatic amines, such as tryptamine and phenethylamine, were reduced by 86.1-100 % after treating with activated carbon. Histamine with a heterocyclic structure decreased by 13-42 %. No significant effects were observed on the levels of aliphatic amines, putrescine, cadaverine, spermine, and spermidine. The major taste component, amino acid nitrogen, was reduced to within 3 %, and brown color removal was reduced depending on the type of activated carbon used. Acid-modified AC-A and AC-B had rough surfaces, high total acidity, low point of zero charge (pHpzc), and rich surface functional groups. Owing to its smooth surface, low total acidity, high pHpzc, and few surface functional groups, AC-C exhibited a higher histamine elimination and less color reduction despite its lower surface area compared to other activated carbons.

Rare oncology therapeutics: review of clinical pharmacology package of drug approvals (2019-2023) by US FDA, best practices and recommendations.

There are many challenges with rare diseases drug development and rare oncology indications are not different. To understand the regulatory landscape as it relates to application of clinical pharmacology principles in rare oncology product development, we reviewed publicly available information of 39 approvals by US FDA between January 2019 and March 2023. The objective was to understand the expected clinical pharmacology studies and knowledge base in such approvals. Model informed drug development (MIDD) applications were also reviewed, as such approaches are expected to play a critical role in filling clinical pharmacology gaps in rare oncology, where number of clinical trials and size of these trials will perhaps continue to be small. The findings highlighted how clinical pharmacology contributed to the evidence of effectiveness, dose optimization and elucidation of intrinsic and extrinsic factors affecting drug's behavior. Clinical pharmacology studies were often integrated with modeling in many of the NDAs/BLAs. Of the post marketing requirements (PMR) received, 18% were for dose optimization, 49% for DDI, 8% for QTc, 49% for specific population, and 5% for food effect. Two post marketing commitments (PMC) were issued for immunogenicity of the 11 biologics submissions. 15% (6 of 39) of the submissions used maximum tolerated dose (MTD) to advance their molecule into Phase 2 studies. Of them 3 approvals received PMR for dose optimization. 3 + 3 was the most prevalent Phase 1 design with use in 74% of the New Drug Applications (NDA)/Biologic License Applications (BLA) reviewed. Rest used innovative approaches such as BLRM, BOIN or mTPi, with BLRM being the most common. Seamless clinical pharmacology and MIDD approaches are paramount for rare oncology drug development.

First-in-human phase I/Ib study of NIZ985, a recombinant heterodimer of IL-15 and IL-15Rα, as a single agent and in combination with spartalizumab in patients with advanced and metastatic solid tumors.

BACKGROUND: Preclinically, interleukin-15 (IL-15) monotherapy promotes antitumor immune responses, which are enhanced when IL-15 is used in combination with immune checkpoint inhibitors (ICIs). This first-in-human study investigated NIZ985, a recombinant heterodimer comprising physiologically active IL-15 and IL-15 receptor α, as monotherapy and in combination with spartalizumab, an anti-programmed cell death protein-1 (anti-PD-1) monoclonal antibody, in patients with advanced solid tumors. METHODS: This phase I/Ib study had two dose-escalation arms: single-agent NIZ985 administered subcutaneously thrice weekly (TIW, 2 weeks on/2 weeks off) or once weekly (QW, 3 weeks on/1 week off), and NIZ985 TIW or QW administered subcutaneously plus spartalizumab (400 mg intravenously every 4 weeks (Q4W)). The dose-expansion phase investigated NIZ985 1 µg/kg TIW/spartalizumab 400 mg Q4W in patients with anti-PD-1-sensitive or anti-PD-1-resistant tumor types stratified according to approved indications. The primary objectives were the safety, tolerability, and the maximum tolerated doses (MTDs) and/or recommended dose for expansion (RDE) of NIZ985 for the dose-expansion phase. RESULTS: As of February 17, 2020, 83 patients (median age: 63 years; range: 28-85) were treated in dose escalation (N=47; single-agent NIZ985: n=27; NIZ985/spartalizumab n=20) and dose expansion (N=36). No dose-limiting toxicities occurred nor was the MTD identified. The most common treatment-related adverse event (TRAE) was injection site reaction (primarily grades 1-2; single-agent NIZ985: 85% (23/27)); NIZ985/spartalizumab: 89% [50/56]). The most common grade 3-4 TRAE was decreased lymphocyte count (single-agent NIZ985: 7% [2/27]; NIZ985/spartalizumab: 5% [3/56]). The best overall response was stable disease in the single-agent arm (30% (8/27)) and partial response in the NIZ985/spartalizumab arm (5% [3/56]; melanoma, pancreatic cancer, gastric cancer). In dose expansion, the disease control rate was 45% (5/11) in the anti-PD-1-sensitive and 20% (5/25) in the anti-PD-1-resistant tumor type cohorts. Pharmacokinetic parameters were similar across arms. The transient increase in CD8+ T cell and natural killer cell proliferation and induction of several cytokines occurred in response to the single-agent and combination treatments. CONCLUSIONS: NIZ985 was well tolerated in the single-agent and NIZ985/spartalizumab regimens. The RDE was established at 1 µg/kg TIW. Antitumor activity of the combination was observed against tumor types known to have a poor response to ICIs. TRIAL REGISTRATION NUMBER: NCT02452268.

Population Pharmacokinetics and Exposure-Response Modeling Analyses of Golimumab in Children and Young Adults With Recently Diagnosed Type 1 Diabetes.

Golimumab was recently evaluated in a phase 2a, randomized, double-blind, placebo-controlled, multicenter study (T1GER study) for safety and efficacy in children and young adults with newly diagnosed type 1 diabetes (T1D). Golimumab showed significant treatment effect where endogenous insulin production was preserved and clinical and metabolic parameters were improved. The objective of this report was to evaluate pharmacokinetic (PK) and pharmacodynamic data from the T1GER study by developing a population pharmacokinetic (PopPK) model and performing exposure-response (ER) analyses. The PopPK model was developed using data from the T1D study and 2 other pediatric studies with golimumab in ulcerative colitis and in polyarticular juvenile idiopathic arthritis. A 1-compartment model with first-order absorption and elimination was applied to describe the concentration-time profiles. Typical parameters normalized to the values in subjects with a standard weight of 70 kg were apparent clearance, 0.850 L/day; apparent volume of distribution, 16.0 L; and absorption rate constant, 1.01/day. From the ER analyses, no clear trends were observed for changes in both C-peptide area under the concentration-time curve and hemoglobin A1c levels for the relatively narrow exposure ranges following the body surface area-based dosing regimen used in this study. In conclusion, the developed PopPK model was able to adequately describe the observed PK of golimumab in patients with T1D. Although golimumab showed significant treatment effect, the ER analyses did not show clear trends within the active treatment group, which may indicate that the exposure from this T1D-specific dosing regimen was at the plateau of the ER curve.

Single-molecule visualization of mRNA circularization during translation.

Translation is mediated by precisely orchestrated sequential interactions among translation initiation components, mRNA, and ribosomes. Biochemical, structural, and genetic techniques have revealed the fundamental mechanism that determines what occurs and when, where and in what order. Most mRNAs are circularized via the eIF4E-eIF4G-PABP interaction, which stabilizes mRNAs and enhances translation by recycling ribosomes. However, studies using single-molecule fluorescence imaging have allowed for the visualization of complex data that opposes the traditional "functional circularization" theory. Here, we briefly introduce single-molecule techniques applied to studies on mRNA circularization and describe the results of in vitro and live-cell imaging. Finally, we discuss relevant insights and questions gained from single-molecule research related to translation.

A Reactive Oxygen Species-Scavenging 'Stealth' Polymer, Poly(thioglycidyl glycerol), Outperforms Poly(ethylene glycol) in Protein Conjugates and Nanocarriers and Enhances Protein Stability to Environmental and Biological Stressors.

This study addresses well-known shortcomings of poly(ethylene glycol) (PEG)-based conjugates. PEGylation is by far the most common method employed to overcome immunogenicity and suboptimal pharmacokinetics of, for example, therapeutic proteins but has significant drawbacks. First, PEG offers no protection from denaturation during lyophilization, storage, or oxidation (e.g., by biological oxidants, reactive oxygen species); second, PEG's inherent immunogenicity, leading to hypersensitivity and accelerated blood clearance (ABC), is a growing concern. We have here developed an 'active-stealth' polymer, poly(thioglycidyl glycerol)(PTGG), which in human plasma is less immunogenic than PEG (35% less complement activation) and features a reactive oxygen species-scavenging and anti-inflammatory action (∼50% less TNF-α in LPS-stimulated macrophages at only 0.1 mg/mL). PTGG was conjugated to proteins via a one-pot process; molar mass- and grafting density-matched PTGG-lysozyme conjugates were superior to their PEG analogues in terms of enzyme activity and stability against freeze-drying or oxidation; the latter is due to sacrificial oxidation of methionine-mimetic PTGG chains. Both in mice and rats, PTGG-ovalbumin displayed circulation half-lives up to twice as long as PEG-ovalbumin, but most importantly─and differently from PEG─without any associated ABC effect seen either in the time dependency of blood concentration, in the liver/splenic accumulation, or in antipolymer IgM/IgG titers. Furthermore, similar pharmacokinetic results were obtained with PTGGylated/PEGylated liposomal nanocarriers. PTGG's 'active-stealth' character therefore makes it a highly promising alternative to PEG for conjugation to biologics or nanocarriers.

Exploiting the distinctive properties of the bacterial and human MutS homolog sliding clamps on mismatched DNA.

MutS homologs (MSHs) are highly conserved core components of DNA mismatch repair. Mismatch recognition provokes ATP-binding by MSH proteins that drives a conformational transition from a short-lived lesion-searching clamp to an extremely stable sliding clamp on the DNA. Here, we have expanded on previous bulk biochemical studies to examine the stability, lifetime, and kinetics of bacterial and human MSH sliding clamps on mismatched DNA using surface plasmon resonance and single-molecule analysis of fluorescently labeled proteins. We found that ATP-bound MSH complexes bound to blocked-end or very long mismatched DNAs were extremely stable over a range of ionic conditions. These observations underpinned the development of a high-throughput Förster resonance energy transfer system that specifically detects the formation of MSH sliding clamps on mismatched DNA. The Förster resonance energy transfer system is capable of distinguishing between HsMSH2-HsMSH3 and HsMSH2-HsMSH6 and appears suitable for chemical inhibitor screens. Taken together, our results provide additional insight into MSH sliding clamps as well as methods to distinguish their functions in mismatch repair.

Single polysome analysis of mRNP.

Eukaryotic translation is a complex process that involves the interplay of various translation factors to convert genetic information into a specific amino acid chain. According to an elegant model of eukaryotic translation initiation, the 3' poly(A) tail of an mRNA, which is occupied by poly(A)-binding proteins (PABPs), communicates with the 5'-cap bound by eIF4E to enhance translation. Although the circularization of mRNA resulting from the communication is widely understood, it has yet to be directly observed. To explore mRNA circularization in translation, we analyzed the level of colocalization of eIF4E, eIF4G, and PABP on individual mRNAs in polysomal and subpolysomal fractions using single polysome analysis. Our results show that the three tested proteins barely coexist in mRNA in either polysomal or subpolysomal fractions, implying that the closed-loop structure generated by the communication between eIF4E, eIF4G, and PAPB may be transient during translation.

Minimal Physiologically-Based Pharmacokinetic (mPBPK) Metamodeling of Target Engagement in Skin Informs Anti-IL17A Drug Development in Psoriasis.

The pharmacologic effect(s) of biotherapeutics directed against soluble targets are driven by the magnitude and duration of free target suppression at the tissue site(s) of action. Interleukin (IL)-17A is an inflammatory cytokine that plays a key role in the pathogenesis of psoriasis. In this work, clinical trial data from two monoclonal antibodies (mAbs) targeting IL-17A for treatment of psoriasis (secukinumab and ixekizumab) were analyzed simultaneously to quantitatively predict their target engagement (TE) profiles in psoriatic skin. First, a model-based meta-analysis (MBMA) for clinical responses was conducted separately for each drug based on dose. Next, a minimal physiologically-based pharmacokinetic (mPBPK) model was built to assess skin site IL-17A target engagement for ixekizumab and secukinumab simultaneously. The mPBPK model captured the observed drug PK, serum total IL-17A, and skin drug concentration-time profiles reasonably well across the different dosage regimens investigated. The developed mPBPK model was then used to predict the average TE (i.e., free IL-17A suppression) in skin achieved over a 12-weeks treatment period for each drug following their respective regimens and subsequently assess the TE-efficacy response relationship. It was predicted that secukinumab achieved 98.6% average TE in the skin at 300 mg q4w SC while ixekizumab achieved 99.9% average TE under 160 mg (loading) followed by 80 mg q2w SC. While direct quantification of free IL-17A levels at the site of action is technically challenging, integrated mPBPK-MBMA approaches offer quantitative predictions of free IL-17A levels at the site of action to facilitate future drug development via IL-17A suppression in psoriasis.

Formation of cellular close-ended tunneling nanotubes through mechanical deformation.

Membrane nanotubes or tunneling nanotubes (TNTs) that connect cells have been recognized as a previously unidentified pathway for intercellular transport between distant cells. However, it is unknown how this delicate structure, which extends over tens of micrometers and remains robust for hours, is formed. Here, we found that a TNT develops from a double filopodial bridge (DFB) created by the physical contact of two filopodia through helical deformation of the DFB. The transition of a DFB to a close-ended TNT is most likely triggered by disruption of the adhesion of two filopodia by mechanical energy accumulated in a twisted DFB when one of the DFB ends is firmly attached through intercellular cadherin-cadherin interactions. These studies pinpoint the mechanistic questions about TNTs and elucidate a formation mechanism.

Population Pharmacokinetic and Exposure-Response Model Simulations: Predicted Exposure and Efficacy for Maintenance Doses of Intravenous Golimumab Every 6 or 8 Weeks in Patients With Moderately to Severely Active Rheumatoid Arthritis.

PURPOSE: Golimumab is approved to treat moderate-to-severe active rheumatoid arthritis when given intravenously at weeks 0 and 4, then every 8 weeks (Q8W) with concomitant methotrexate. These analyses assessed whether a shorter dosing interval could ameliorate diminished efficacy experienced by a small proportion of patients toward the end of the dosing interval. METHODS: Population pharmacokinetic and exposure-response modeling simulations were performed for intravenous golimumab 2 mg/kg at weeks 0 and 4, then Q8W or every 6 weeks (Q6W) through 1 year. A 2-compartment pharmacokinetic model with linear clearance developed based on GO-FURTHER (A Multicenter, Randomized, Double-blind, Placebo-controlled Trial of Golimumab, an Anti-TNFα Monoclonal Antibody, Administered Intravenously, in Patients With Active Rheumatoid Arthritis Despite Methotrexate Therapy) study data was used for pharmacokinetic simulations. A latent-variable indirect exposure-response model developed based on GO-FURTHER American College of Rheumatology (ACR) 20%/50%/70% improvement (ACR20, ACR50, and ACR70, respectively) data was used to predict clinical endpoints of ACR20/ACR50/ACR70 response rates. FINDINGS: For Q6W and Q8W dosing, respectively, predicted median golimumab steady-state trough (Ctrough,ss) concentrations were 0.57 and 0.24 µg/mL, and Cmax at steady state values were 33.1 and 32.9 µg/mL. Predicted peak median ACR20 steady-state response rates were 76.7% (Q6W) and 75.6% (Q8W). Predicted median ACR20 response rates at Ctrough,ss increased by 4.7 percentage points with Q6W (73.7%) versus Q8W (69.0%) dosing. Greater improvement in ACR20 response rates at trough time points was predicted in patients with lower golimumab trough serum concentrations. Consistent findings were observed for ACR50/ACR70 response rates. IMPLICATIONS: These simulations suggest that intravenous golimumab Q6W dosing increases golimumab Ctrough,ss, which may improve clinical response in the small proportion of patients with rheumatoid arthritis with waning efficacy at the end of the standard dosing interval. CLINICALTRIALS: gov identifier: NCT00973479. Clinicaltrialsregister.eu: EudraCT 2008-006064-11.

The flip-flop configuration of the PABP-dimer leads to switching of the translation function.

Poly(A)-binding protein (PABP) is a translation initiation factor that interacts with the poly(A) tail of mRNAs. PABP bound to poly(A) stimulates translation by interacting with the eukaryotic initiation factor 4G (eIF4G), which brings the 3' end of an mRNA close to its 5' m7G cap structure through consecutive interactions of the 3'-poly(A)-PABP-eIF4G-eIF4E-5' m7G cap. PABP is a highly abundant translation factor present in considerably larger quantities than mRNA and eIF4G in cells. However, it has not been elucidated how eIF4G, present in limited cellular concentrations, is not sequestered by mRNA-free PABP, present at high cellular concentrations, but associates with PABP complexed with the poly(A) tail of an mRNA. Here, we report that RNA-free PABPs dimerize with a head-to-head type configuration of PABP, which interferes in the interaction between PABP and eIF4G. We identified the domains of PABP responsible for PABP-PABP interaction. Poly(A) RNA was shown to convert the PABP-PABP complex into a poly(A)-PABP complex, with a head-to-tail-type configuration of PABP that facilitates the interaction between PABP and eIF4G. Lastly, we showed that the transition from the PABP dimer to the poly(A)-PABP complex is necessary for the translational activation function.

Prediction of Individual Analgesic Response to Intravenous Lidocaine in Painful Diabetic Peripheral Neuropathy: A Randomized, Placebo-controlled, Crossover Trial.

OBJECTIVES: Intravenous lidocaine can alleviate painful diabetic peripheral neuropathy (DPN) in some patients. Whether quantitative sensory testing (QST) can identify treatment responders has not been prospectively tested. MATERIALS AND METHODS: This was a prospective, randomized, double-blind, crossover, placebo-controlled trial comparing intravenous lidocaine to normal saline (placebo) for painful DPN. Thirty-four participants with painful DPN were enrolled and administered intravenous lidocaine (5 mg/kg ideal body weight) or placebo as a 40-minute infusion, after a battery of QST parameters were tested on the dorsal foot, with a 3-week washout period between infusions. RESULTS: Thirty-one participants completed both study sessions and were included in the final analysis. Lidocaine resulted in a 51% pain reduction 60 to 120 minutes after infusion initiation, as assessed on a 0 to 10 numerical rating scale, while placebo resulted in a 33.5% pain reduction (difference=17.6%, 95% confidence interval [CI], 1.9%-33.3%, P=0.03). Neither mechanical pain threshold, heat pain threshold, or any of the other measured QST parameters predicted the response to treatment. Lidocaine administration reduced mean Neuropathic Pain Symptom Inventory paresthesia/dysesthesia scores when compared with placebo by 1.29 points (95% CI, -2.03 to -0.55, P=0.001), and paroxysmal pain scores by 0.84 points (95% CI, -1.62 to -0.56, P=0.04), without significant changes in burning, pressing or evoked pain subscores. DISCUSSION: While some participants reported therapeutic benefit from lidocaine administration, QST measures alone were not predictive of response to treatment. Further studies, powered to test more complex phenotypic interactions, are required to identify reliable predictors of response to pharmacotherapy in patients with DPN.

Inclusion of Medium-Chain Triglyceride in Lipid-Based Formulation of Cannabidiol Facilitates Micellar Solubilization In Vitro, but In Vivo Performance Remains Superior with Pure Sesame Oil Vehicle.

Oral sesame oil-based formulation facilitates the delivery of poorly water-soluble drug cannabidiol (CBD) to the lymphatic system and blood circulation. However, this natural oil-based formulation also leads to considerable variability in absorption of CBD. In this work, the performance of lipid-based formulations with the addition of medium-chain triglyceride (MCT) or surfactants to the sesame oil vehicle has been tested in vitro and in vivo using CBD as a model drug. The in vitro lipolysis has shown that addition of the MCT leads to a higher distribution of CBD into the micellar phase. Further addition of surfactants to MCT-containing formulations did not improve distribution of the drug into the micellar phase. In vivo, formulations containing MCT led to lower or similar concentrations of CBD in serum, lymph and MLNs, but with reduced variability. MCT improves the emulsification and micellar solubilization of CBD, but surfactants did not facilitate further the rate and extent of lipolysis. Even though addition of MCT reduces the variability, the in vivo performance for the extent of both lymphatic transport and systemic bioavailability remains superior with a pure natural oil vehicle.

Administration in fed state but not controlled release in the colon increases oral bioavailability of DF030263, a promising drug candidate for chronic lymphocytic leukemia.

For treatment of chronic cancers, the oral administration route is preferred as it provides numerous advantages over other delivery routes. However, these benefits of oral chemotherapy can be limited due to unfavorable pharmacokinetics. Accordingly, pharmacokinetic development of chemotherapeutic agents is crucial to the improvement of cancer treatment. In this study, assessment and optimization of biopharmaceutical properties of a promising drug candidate for cyclin-dependent kinase 9 (CDK9) inhibitor (DF030263) was performed to promote oral delivery. Oral bioavailability of DF030263 in fasted rats was 23.8%, and a distinct double-peak phenomenon was observed. A two-site absorption windows mechanism was proposed as a possible explanation to the phenomenon. The two-site absorption window hypothesis was supported by in vitro solubility assays in biorelevant fluids with different pH levels, as well as by in silico simulation by GastroPlus™. Controlled release to the colon was conducted in rats in order to exploit the colonic absorption window but did not improve the oral bioavailability. On the other hand, oral administration at postprandial conditions in rats (performed based on the high in vitro solubility in fed state simulated fluid and reduced pH-dependency) resulted in an almost 3-fold increase in bioavailability to 63.6%. In conclusion, this study demonstrates an efficient in vitro-in vivo-in silico drug development approach for improving the oral bioavailability of DF030263, a promising candidate for the treatment of chronic lymphocytic leukemia.

TRIM28 functions as a negative regulator of aggresome formation.

Selective recognition and elimination of misfolded polypeptides are crucial for protein homeostasis. When the ubiquitin-proteasome system is impaired, misfolded polypeptides tend to form small cytosolic aggregates and are transported to the aggresome and eventually eliminated by the autophagy pathway. Despite the importance of this process, the regulation of aggresome formation remains poorly understood. Here, we identify TRIM28/TIF1ß/KAP1 (tripartite motif containing 28) as a negative regulator of aggresome formation. Direct interaction between TRIM28 and CTIF (cap binding complex dependent translation initiation factor) leads to inefficient aggresomal targeting of misfolded polypeptides. We also find that either treatment of cells with poly I:C or infection of the cells by influenza A viruses triggers the phosphorylation of TRIM28 at S473 in a way that depends on double-stranded RNA-activated protein kinase. The phosphorylation promotes association of TRIM28 with CTIF, inhibits aggresome formation, and consequently suppresses viral proliferation. Collectively, our data provide compelling evidence that TRIM28 is a negative regulator of aggresome formation.Abbreviations: BAG3: BCL2-associated athanogene 3; CTIF: CBC-dependent translation initiation factor; CED: CTIF-EEF1A1-DCTN1; DCTN1: dynactin subunit 1; EEF1A1: eukaryotic translation elongation factor 1 alpha 1; EIF2AK2: eukaryotic translation initiation factor 2 alpha kinase 2; HDAC6: histone deacetylase 6; IAV: influenza A virus; IP: immunoprecipitation; PLA: proximity ligation assay; polypeptidyl-puro: polypeptidyl-puromycin; qRT-PCR: quantitative reverse-transcription PCR; siRNA: small interfering RNA.

Natural sesame oil is superior to pre-digested lipid formulations and purified triglycerides in promoting the intestinal lymphatic transport and systemic bioavailability of cannabidiol.

Lipid-based formulations play a significant role in oral delivery of lipophilic drugs. Previous studies have shown that natural sesame oil promotes the intestinal lymphatic transport and oral bioavailability of the highly lipophilic drug cannabidiol (CBD). However, both lymphatic transport and systemic bioavailability were also associated with considerable variability. The aim of this study was to test the hypothesis that pre-digested lipid formulations (oleic acid, linoleic acid, oleic acid with 2-oleoylglycerol, oleic acid with 2-oleoylglycerol and oleic acid with glycerol) could reduce variability and increase the extent of the intestinal lymphatic transport and oral bioavailability of CBD. The in vivo studies in rats showed that pre-digested or purified triglyceride did not improve the lymphatic transport and bioavailability of CBD in comparison to sesame oil. Moreover, the results suggest that both the absorption of lipids and the absorption of co-administered CBD were more efficient following administration of natural sesame oil vehicle compared with pre-digested lipids or purified trioleate. Although multiple small molecule constituents and unique fatty acid compositions could potentially contribute to a better performance of sesame oil in oral absorption of lipids or CBD, further investigation will be needed to identify the mechanisms involved.

Linker domain function predicts pathogenic MLH1 missense variants.

The pathogenic consequences of 369 unique human HsMLH1 missense variants has been hampered by the lack of a detailed function in mismatch repair (MMR). Here single-molecule images show that HsMSH2-HsMSH6 provides a platform for HsMLH1-HsPMS2 to form a stable sliding clamp on mismatched DNA. The mechanics of sliding clamp progression solves a significant operational puzzle in MMR and provides explicit predictions for the distribution of clinically relevant HsMLH1 missense mutations.