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1.
Nature ; 628(8007): 326-332, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38480891

ABSTRACT

Heteroarenes are ubiquitous motifs in bioactive molecules, conferring favourable physical properties when compared to their arene counterparts1-3. In particular, semisaturated heteroarenes possess attractive solubility properties and a higher fraction of sp3 carbons, which can improve binding affinity and specificity. However, these desirable structures remain rare owing to limitations in current synthetic methods4-6. Indeed, semisaturated heterocycles are laboriously prepared by means of non-modular fit-for-purpose syntheses, which decrease throughput, limit chemical diversity and preclude their inclusion in many hit-to-lead campaigns7-10. Herein, we describe a more intuitive and modular couple-close approach to build semisaturated ring systems from dual radical precursors. This platform merges metallaphotoredox C(sp2)-C(sp3) cross-coupling with intramolecular Minisci-type radical cyclization to fuse abundant heteroaryl halides with simple bifunctional feedstocks, which serve as the diradical synthons, to rapidly assemble a variety of spirocyclic, bridged and substituted saturated ring types that would be extremely difficult to make by conventional methods. The broad availability of the requisite feedstock materials allows sampling of regions of underexplored chemical space. Reagent-controlled radical generation leads to a highly regioselective and stereospecific annulation that can be used for the late-stage functionalization of pharmaceutical scaffolds, replacing lengthy de novo syntheses.


Subject(s)
Carbon , Chemistry Techniques, Synthetic , Heterocyclic Compounds, 1-Ring , Pharmaceutical Preparations , Carbon/chemistry , Cyclization , Heterocyclic Compounds, 1-Ring/chemical synthesis , Heterocyclic Compounds, 1-Ring/chemistry , Solubility , Oxidation-Reduction , Photochemistry , Pharmaceutical Preparations/chemical synthesis , Pharmaceutical Preparations/chemistry , Chemistry Techniques, Synthetic/methods
2.
Br J Nutr ; 121(8): 945-954, 2019 04.
Article in English | MEDLINE | ID: mdl-30696504

ABSTRACT

Discrete episodes of overconsumption may induce a positive energy balance and impair metabolic control. However, the effects of an ecologically relevant, single day of balanced macronutrient overfeeding are unknown. Twelve healthy men (of age 22 (sd 2) years, BMI 26·1 (sd 4·2) kg/m2) completed two 28 h, single-blind experimental trials. In a counterbalanced repeated measures design, participants either consumed their calculated daily energy requirements (energy balance trial (EB): 10 755 (sd 593) kJ) or were overfed by 50 % (overfeed trial (OF): 16 132 (sd 889) kJ) under laboratory supervision. Participants returned to the laboratory the next day, after an overnight fast, to complete a mixed-meal tolerance test (MTT). Appetite was not different between trials during day 1 (P>0·211) or during the MTT in the fasted or postprandial state (P>0·507). Accordingly, plasma acylated ghrelin, total glucagon-like peptide-1 and total peptide YY concentrations did not differ between trials during the MTT (all P>0·335). Ad libitum energy intake, assessed upon completion of the MTT, did not differ between trials (EB 6081 (sd 2260) kJ; OF 6182 (sd 1960) kJ; P=0·781). Plasma glucose and insulin concentrations were not different between trials (P>0·715). Fasted NEFA concentrations were lower in OF compared with EB (P=0·005), and TAG concentrations increased to a greater extent on OF than on EB during the MTT (P=0·009). The absence of compensatory changes in appetite-related variables after 1 d of mixed macronutrient overfeeding highlights the limited physiological response to defend against excess energy intake. This supports the concept that repeated discrete episodes of overconsumption may promote weight gain, while elevations in postprandial lipaemia may increase CVD risk.


Subject(s)
Appetite/drug effects , Energy Intake/drug effects , Hyperlipidemias/chemically induced , Hyperphagia/physiopathology , Nutrients/adverse effects , Healthy Volunteers , Humans , Hyperphagia/complications , Male , Nutrients/administration & dosage , Postprandial Period , Single-Blind Method , Young Adult
3.
Pediatr Diabetes ; 19(5): 945-954, 2018 08.
Article in English | MEDLINE | ID: mdl-29473705

ABSTRACT

OBJECTIVE: To determine the safety and pharmacokinetics of alpha-1 antitrypsin (AAT) in adults and children. RESEARCH DESIGN AND METHODS: Short-term AAT treatment restores euglycemia in the non-obese mouse model of type 1 diabetes. A phase I multicenter study in 16 subjects with new-onset type 1 diabetes studied the safety and pharmacokinetics of Aralast NP (AAT). This open-label, dose-escalation study enrolled 8 adults aged 16 to 35 years and 8 children aged 8 to 15 years within 100 days of diagnosis, to receive 12 infusions of AAT: a low dose of 45 mg/kg weekly for 6 weeks, followed by a higher dose of 90 mg/kg for 6 weeks. RESULTS: C-peptide secretion during a mixed meal, hemoglobin A1c (HbA1c), and insulin usage remained relatively stable during the treatment period. At 72 hours after infusion of 90 mg/kg, mean levels of AAT fell below 2.0 g/L for 7 of 15 subjects. To identify a plasma level of AAT likely to be therapeutic, pharmacodynamic ex vivo assays were performed on fresh whole blood from adult subjects. Polymerase chain reaction (PCR) analyses were performed on inhibitor of IKBKE, NOD1, TLR1, and TRAD gene expression, which are important for activation of nuclear factor-κB (NF-κB) and apoptosis pathways. AAT suppressed expression dose-dependently; 50% inhibition was achieved in the 2.5 to 5.0 mg/mL range. CONCLUSIONS: AAT was well tolerated and safe in subjects with new-onset type 1 diabetes. Weekly doses of AAT greater than 90 mg/kg may be necessary for an optimal therapeutic effect.


Subject(s)
Diabetes Mellitus, Type 1/drug therapy , alpha 1-Antitrypsin/therapeutic use , Adolescent , Adult , C-Peptide/blood , Child , Diabetes Mellitus, Type 1/blood , Female , Glycated Hemoglobin/metabolism , Humans , Infusions, Intravenous , Male , Young Adult , alpha 1-Antitrypsin/pharmacokinetics
4.
Curr Opin Endocrinol Diabetes Obes ; 20(4): 285-91, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23807601

ABSTRACT

PURPOSE OF REVIEW: Above 60 non-HLA genes have been associated with T1D, many of which are immune-related genes. One challenge following identification of these genes is finding causative connections between risk alleles and disease. Phenotypes linked to T1D-associated genetic variants are beginning to help us better understand the cellular and molecular mechanisms underlying T1D. RECENT FINDINGS: The list of immune-related genes with T1D-associated polymorphisms will be reviewed and cellular phenotypes correlating with these variants will be described highlighting recent finding from variants in the PTPN22 gene and genes encoding proteins in theIL-2/IL2R signaling pathway. SUMMARY: Building from extensive genome-wide association studies, we are discovering cellular and molecular phenotypes that may help unravel the underlying causes of T1D.


Subject(s)
Diabetes Mellitus, Type 1/genetics , Diabetes Mellitus, Type 1/immunology , Polymorphism, Genetic/immunology , Diabetes Mellitus, Type 1/metabolism , Genetic Predisposition to Disease , Genetic Variation , Genome-Wide Association Study , Humans , Phenotype
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