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1.
Hum Reprod ; 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38840410

RESUMEN

STUDY QUESTION: In non-male factor infertile couples, are there any differences in the developmental outcomes between children born through ICSI and conventional IVF (cIVF)? SUMMARY ANSWER: In this preliminary study, ICSI and cIVF seem to have a comparable effect on developmental outcomes after 12 months in children born to non-male factor infertile couples. WHAT IS KNOWN ALREADY: ICSI, an invasive technique, has raised concerns about potential developmental abnormalities in children. Limited data are available regarding the developmental outcomes of ICSI-conceived infants born to non-male factor infertile couples. STUDY DESIGN, SIZE, DURATION: This prospective cohort study involved a follow-up of all children aged 12 months or older who were born from pregnancies resulting from either ICSI or cIVF as part of a previous randomized controlled trial (RCT) (NCT03428919). PARTICIPANTS/MATERIALS, SETTING, METHODS: In the original RCT, 1064 women were randomly assigned to the ICSI or cIVF groups (532 women for each group). Follow-up was conducted with 155 couples (195 children) in the ICSI group and 141 couples (185 children) in the cIVF group. The Vietnamese version of the Ages & Stages Third Edition Questionnaires (ASQ-3) and the Development Red Flags questionnaires were completed by the participants. A total of 141 (90.1%) women (177 children) in the ICSI group and 113 (80.1%) women (145 children) in the cIVF group returned fully completed questionnaires. The primary outcomes were the developmental outcomes based on responses to the ASQ-3 and the Red Flags questionnaire. MAIN RESULTS AND THE ROLE OF CHANCE: The mean age of children at follow-up was 19.5 ± 5.0 months in the ICSI group and 19.3 ± 5.5 months in the cIVF group. The mean height and weight of children in both groups were similar. The overall proportion of children with any abnormal ASQ-3 score did not differ significantly between the ICSI and cIVF groups (16.9% vs 13.1%, P = 0.34). The proportion of children with Red Flag signs was also comparable between the two groups (6.2% vs 9.2%, P = 0.36, ICSI vs cIVF, respectively). LIMITATIONS, REASONS FOR CAUTION: Despite a reasonably high follow-up response rate, there is a potential risk of sampling bias, and overall, the number of children with developmental abnormalities was very small. The study relied solely on questionnaires as screening tools, rather than incorporating additional behavioral observations or physical developmental tests; this may have affected the statistical power and the significance of between-group comparisons. WIDER IMPLICATIONS OF THE FINDINGS: The current findings contribute to the existing evidence and support the comparative safety of ICSI and cIVF regarding early childhood development. However, more extensive and prolonged follow-up data for these children are needed to draw definitive conclusions. STUDY FUNDING/COMPETING INTEREST(S): No external funding was received for this study, and no authors reported conflicting interests. TRIAL REGISTRATION NUMBER: NCT04866524 (clinicaltrials.gov).

3.
J Med Chem ; 67(4): 2369-2378, 2024 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-38335279

RESUMEN

There remains a need to develop novel SARS-CoV-2 therapeutic options that improve upon existing therapies by an increased robustness of response, fewer safety liabilities, and global-ready accessibility. Functionally critical viral main protease (Mpro, 3CLpro) of SARS-CoV-2 is an attractive target due to its homology within the coronaviral family, and lack thereof toward human proteases. In this disclosure, we outline the advent of a novel SARS-CoV-2 3CLpro inhibitor, CMX990, bearing an unprecedented trifluoromethoxymethyl ketone warhead. Compared with the marketed drug nirmatrelvir (combination with ritonavir = Paxlovid), CMX990 has distinctly differentiated potency (∼5× more potent in primary cells) and human in vitro clearance (>4× better microsomal clearance and >10× better hepatocyte clearance), with good in vitro-to-in vivo correlation. Based on its compelling preclinical profile and projected once or twice a day dosing supporting unboosted oral therapy in humans, CMX990 advanced to a Phase 1 clinical trial as an oral drug candidate for SARS-CoV-2.


Asunto(s)
COVID-19 , Humanos , SARS-CoV-2 , Diferenciación Celular , Revelación , Inhibidores de Proteasas/farmacología , Inhibidores de Proteasas/uso terapéutico , Antivirales/farmacología
4.
Acta Pharm Sin B ; 13(4): 1648-1659, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37139407

RESUMEN

Peptides are increasingly important resources for biological and therapeutic development, however, their intrinsic susceptibility to proteolytic degradation represents a big hurdle. As a natural agonist for GLP-1R, glucagon-like peptide 1 (GLP-1) is of significant clinical interest for the treatment of type-2 diabetes mellitus, but its in vivo instability and short half-life have largely prevented its therapeutic application. Here, we describe the rational design of a series of α/sulfono-γ-AA peptide hybrid analogues of GLP-1 as the GLP-1R agonists. Certain GLP-1 hybrid analogues exhibited enhanced stability (t 1/2 > 14 days) compared to t 1/2 (<1 day) of GLP-1 in the blood plasma and in vivo. These newly developed peptide hybrids may be viable alternative of semaglutide for type-2 diabetes treatment. Additionally, our findings suggest that sulfono-γ-AA residues could be adopted to substitute canonical amino acids residues to improve the pharmacological activity of peptide-based drugs.

5.
Reprod Sci ; 30(10): 3071-3076, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37171775

RESUMEN

To compare the rate of positive thyroid peroxidase antibodies (TPO Ab) between women with different polycystic ovary syndrome (PCOS) phenotypes and women without PCOS. This is a retrospective cohort study. Women with PCOS at My Duc Hospital between June 1, 2020, and March 27, 2021, were matched with non-PCOS women by age. TPO Ab (cut-off: 34 IU/mL) and thyroid-stimulating hormone (TSH) levels were measured as markers of Hashimoto thyroiditis and thyroid function, respectively. One thousand eight hundred eight infertile women were included, 904 with PCOS (mean age 29.0 ± 3.58 years) and 904 without PCOS (29.1 ± 3.4 years; controls). Women with PCOS had a higher body mass index (22.8 ± 3.84 vs. 19.9 ± 2.23 kg/m2, p < 0.001), but most were not overweight/obese. Rates of positive TPO Ab in women with versus without PCOS were 8.2% and 8.4%, respectively (p = 0.932). Rates of positive TPO Ab in patients with PCOS phenotype A, B, C, or D were not statistically different (7.5%, 2.9%, 20.0%, and 7.8%, respectively). Median TSH concentrations were similar in the PCOS and control groups (1.84 mIU/L vs. 1.78 mIU/L, respectively; p = 0.194). Based on a linear regression model, there was no correlation between either BMI or the estradiol to progesterone ratio and TPO Ab status. In a large population of infertile women with PCOS who were mostly lean patients, rates of positive TPO Ab across all four PCOS phenotypes did not differ significantly from those in women without PCOS. These findings did not support the hypothesis that PCOS is a risk factor for Hashimoto thyroiditis.


Asunto(s)
Enfermedad de Hashimoto , Infertilidad Femenina , Síndrome del Ovario Poliquístico , Humanos , Femenino , Adulto , Síndrome del Ovario Poliquístico/complicaciones , Síndrome del Ovario Poliquístico/epidemiología , Estudios Retrospectivos , Tirotropina , Yoduro Peroxidasa
6.
J Med Food ; 26(4): 262-269, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37071614

RESUMEN

This study aims to assess the effectiveness and safety of plant-derived food supplement Ich Nieu Khang (INK) as a dietary supplement for overactive bladder (OAB) symptoms. A total of 50 patients 18-80 years of age with the diagnosis and symptoms of the OAB were enrolled in the study and followed up for 30 days. The INK treatment efficacy, in terms of changes in nocturnal and day-time urination frequency, urination incontinence episodes, level of OAB symptoms according to Homma's OABSS scale, sleep quality according to Pittsburg Sleep Quality Index (PSQI), and possible side effects of the INK phytotherapy, was evaluated. INK significantly improved all OAB symptoms scores with a reduction of average nocturia from 4.06 ± 1.53 to 1.14 ± 0.94, the daily average urination urgency from 7.67 ± 5.00 to 5. 82 ± 3.70, the daily average frequency of urination from 9.96 ± 4.04 to 8.00 ± 3.70, weekly average incontinence of urination from 0.92 ± 1.56 to 0.60 ± 1.02, and OABSS Homma's score decreased from 9.31 ± 1.44 to 6.8 ± 2.21. INK phytotherapy also resulted in sleep quality improvement by PSQI score decreasing from 13.11 ± 1.33 to 10.54 ± 2.21. There were no adverse effects and abnormalities in paraclinical parameters with INK therapy. The results of our study suggest that INK dietary supplement is effective and safe phytotherapy for patients with primary OAB symptoms within 30 days of treatment. Larger control clinical trials are warranted to confirm our findings and promote wider use of INK for OAB and possible other age-related urination disorders.


Asunto(s)
Vejiga Urinaria Hiperactiva , Humanos , Lactante , Vejiga Urinaria Hiperactiva/tratamiento farmacológico , Vejiga Urinaria Hiperactiva/diagnóstico , Micción , Resultado del Tratamiento , Sueño , Calidad de Vida
7.
Acta Obstet Gynecol Scand ; 102(5): 626-634, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36905390

RESUMEN

INTRODUCTION: Preterm birth is the most common cause of neonatal morbidity and mortality. Women with twin pregnancies and a short cervical length are at high risk for preterm birth. Vaginal progesterone and cervical pessary have been proposed as potential strategies to reduce preterm birth in this high-risk population. Therefore, we aimed to compare the effectiveness of cervical pessary and vaginal progesterone in improving developmental outcomes of children born to women with twin pregnancies and mid-trimester short cervical length. MATERIAL AND METHODS: This was a follow-up study (NCT04295187) of all children at 24 months of age, born from women treated with cervical pessary or progesterone to prevent preterm birth in a randomized controlled trial (NCT02623881). We used a validated Vietnamese version of Ages & Stages Third Edition Questionnaires (ASQ-3) and a red flag questionnaire. In surviving children, we compared the mean ASQ-3 scores, abnormal ASQ-3 scores, the number of children with any abnormal ASQ-3 scores and red flag signs between the two groups. We reported the composite outcome of perinatal death or survival with any abnormal ASQ-3 score in offspring. These outcomes were also calculated in a subgroup of women with a cervical length ≤28 mm (<25th percentile). RESULTS: In the original randomized controlled trial, we randomized 300 women to pessary or progesterone. After counting the number of perinatal deaths and lost to follow-up, 82.8% parents in the pessary group and 82.5% parents in progesterone group returned the questionnaire. The mean ASQ-3 scores of the five skills and red flag signs did not differ significantly between the two groups. However, the percentage of children having abnormal ASQ-3 scores in fine motor skills was significantly lower in the progesterone group (6.1% vs 1.3%, P = 0.01). There were no significant differences in the composite outcome of perinatal death or survival with any abnormal ASQ-3 score in unselected women and in those with cervical length ≤28 mm. CONCLUSIONS: Cervical pessary and vaginal progesterone may have comparable effects on developmental outcomes in children at ≥24 months of age, born to women with twin pregnancies and short cervical length. However, this finding could be likely due to a lack of study power.


Asunto(s)
Muerte Perinatal , Nacimiento Prematuro , Embarazo , Recién Nacido , Femenino , Niño , Humanos , Progesterona , Embarazo Gemelar , Estudios de Seguimiento , Nacimiento Prematuro/prevención & control , Pesarios , Cuello del Útero , Administración Intravaginal
8.
Angew Chem Int Ed Engl ; 62(9): e202211794, 2023 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-36524997

RESUMEN

A flurry of recent research has centered on harnessing the power of nickel catalysis in organic synthesis. These efforts have been bolstered by contemporaneous development of well-defined nickel (pre)catalysts with diverse structure and reactivity. In this report, we present ten different bench-stable, 18-electron, formally zero-valent nickel-olefin complexes that are competent pre-catalysts in various reactions. Our investigation includes preparations of novel, bench-stable Ni(COD)(L) complexes (COD=1,5-cyclooctadiene), in which L=quinone, cyclopentadienone, thiophene-S-oxide, and fulvene. Characterization by NMR, IR, single-crystal X-ray diffraction, cyclic voltammetry, thermogravimetric analysis, and natural bond orbital analysis sheds light on the structure, bonding, and properties of these complexes. Applications in an assortment of nickel-catalyzed reactions underscore the complementary nature of the different pre-catalysts within this toolkit.

9.
Eur J Protistol ; 86: 125933, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36308895

RESUMEN

This study provides new data on ecology of testate amoebae in the waterbodies of the Central Highlands and South-Central Coast regions of Vietnam. A total of 108 species and subspecies including six new records for Vietnam were identified. One new species Difflugia quangtrani sp. nov. was described. Difflugia, Arcella, and Centropyxis were the most species-rich genera, and Centropyxis aculeata was the most common species. The results of NMDS and ANOSIM analyses for the first time showed significant differences in composition of tropical freshwater testate amoeba communities within both various types of waterbodies (reservoir, river, and wetland) and biotopes (plankton and benthos). Average species richness per sample in different types of waterbodies was similar, while that of plankton was statistically higher than in benthos. The distance decay of similarity in tropical freshwater testate amoeba community of both plankton and benthos was observed for the first time indicating the importance of geographical distance in testacean species composition changes between samples. Redundancy analyses followed by the forward selection have determined elevation, pH, and dissolved oxygen as significant factors that affect tropical freshwater testacean community. More large-scale climatic and small-scale hydrological and hydrochemical variables should be included into further studies to find out most important factors determining structure of freshwater testacean assemblages.


Asunto(s)
Amoeba , Biodiversidad , Vietnam , Ecología , Hidrología , Plancton
10.
Hum Reprod ; 37(8): 1871-1879, 2022 07 30.
Artículo en Inglés | MEDLINE | ID: mdl-35595193

RESUMEN

STUDY QUESTION: Is there any difference in developmental outcomes in children born after capacitation IVM (CAPA IVM) compared with conventional IVF? SUMMARY ANSWER: Overall development up to 24 months of age was comparable in children born after CAPA IVM compared with IVF. WHAT IS KNOWN ALREADY: IVM has been shown to be a feasible alternative to conventional IVF in women with a high antral follicle count (AFC). In addition to live birth rate, childhood development is also a relevant metric to compare between the two approaches to ART and there are currently no data on this. STUDY DESIGN, SIZE, DURATION: This study was a follow-up of babies born to women who participated in a randomized controlled trial comparing IVM with a pre-maturation step (CAPA IVM) and IVF. Developmental assessments were performed on 231 children over 24 months of follow-up. PARTICIPANTS/MATERIALS, SETTING, METHODS: Participants in the randomized controlled trial had an indication for ART and a high AFC (≥24 follicles in both ovaries). They were randomized to undergo one cycle of either IVM (n = 273) or IVF (n = 273). Of these, 96 women and 118 women, respectively, had live births. Seventy-six women (94 children, 79.2%) and 104 women (137 children, 88.1%), respectively, completed Ages & Stages Third Edition Questionnaire assessment (ASQ-3), and underwent evaluation of Developmental Red Flags at 6, 12 and 24 months of age. MAIN RESULTS AND THE ROLE OF CHANCE: Baseline characteristics of participants in the follow-up study between the IVM and IVF groups were comparable. Overall, there were no significant differences in ASQ-3 scores at 6, 12 and 24 months between children born after IVM or IVF. The proportion of children with developmental red flags was low and did not differ between the two groups. Slightly, but significantly, lower ASQ-3 problem solving and personal-social scores in twins from the IVM versus IVF group at 6 months were still within the normal range and had caught up to the IVF group in the 12- and 24-month assessments. The number of children confirmed to have abnormal mental and/or motor development after specialist assessment was four in the IVM group and two in the IVF group (relative risk 2.91, 95% CI 0.54-15.6; P = 0.23). LIMITATIONS, REASONS FOR CAUTION: This study is an open-label follow-up of participants in a randomized controlled trial, and not all original trial subjects took part in the follow-up. The self-selected nature of the follow-up population could have introduced bias, and the sample size may have been insufficient to detect significant between-group differences in developmental outcomes. WIDER IMPLICATIONS OF THE FINDINGS: Based on the current findings at 2 years of follow-up, there does not appear to be any significant concern about the effects of IVM on childhood development. These data add to the evidence available to physicians when considering different approaches to fertility treatment, but require validation in larger studies. STUDY FUNDING/COMPETING INTEREST(S): This work was funded by the Vietnam National Foundation for Science and Technology Development (NAFOSTED) under grant number FWO.106-YS.2017.02. L.N.V. has received speaker and conference fees from Merck, grant, speaker and conference fees from Merck Sharpe and Dohme, and speaker, conference and scientific board fees from Ferring; T.M.H. has received speaker fees from Merck, Merck Sharp and Dohme, and Ferring; R.J.N. has receives grant funding from the National Health and Medical Research Council (NHMRC) of Australia; B.W.M. has acted as a paid consultant to Merck, ObsEva and Guerbet and is the recipient of grant money from an NHMRC Investigator Grant; J.E.J.S. reports lecture fees from Ferring Pharmaceuticals, Biomérieux and Besins Female Healthcare, grants from Fund for Research Flanders (FWO) and is co-inventor on granted patents on CAPA-IVM methodology in the USA (US10392601B2) and Europe (EP3234112B1); T.D.P., M.H.N.N., N.A.N., T.T.L., V.T.T.T., N.T.N., H.L.T.H. and X.T.H.L. have no financial relationships with any organizations that might have an interest in the submitted work in the previous 3 years, and no other relationships or activities that could appear to have influenced the submitted work. TRIAL REGISTRATION NUMBER: NCT04296357 (www.clinicaltrials.gov). TRIAL REGISTRATION DATE: 5 March 2020. DATE OF FIRST PATIENT'S ENROLMENT: 7 March 2020.


Asunto(s)
Tasa de Natalidad , Inducción de la Ovulación , Niño , Femenino , Fertilización In Vitro/métodos , Estudios de Seguimiento , Humanos , Nacimiento Vivo , Inducción de la Ovulación/métodos , Embarazo
11.
ACS Chem Biol ; 17(5): 1249-1258, 2022 05 20.
Artículo en Inglés | MEDLINE | ID: mdl-35417146

RESUMEN

Recent clinical trials have revealed that the chimeric peptide hormones simultaneously activating glucagon-like peptide-1 receptor (GLP-1R) and glucose-dependent insulinotropic polypeptide receptor (GIPR) demonstrate superior efficacy in glycemic control and body weight reduction, better than those activating the GLP-1R alone. However, the linear peptide-based GLP-1R/GIPR dual agonists are susceptible to proteolytic cleavage by common digestive enzymes present in the gastrointestinal tract and thus not suitable for oral administration. Here, we report the design and synthesis of biaryl-stapled peptides, with and without fatty diacid attachment, that showed potent GLP-1R/GIPR dual agonist activities. Compared to a linear peptide dual agonist and semaglutide, the biaryl-stapled peptides displayed drastically improved proteolytic stability against the common digestive enzymes. Furthermore, two stapled peptides showed excellent efficacy in an oral glucose tolerance test in mice, owing to their potent receptor activity in vitro and good pharmacokinetics exposure upon subcutaneous injection. By exploring a more comprehensive set of biaryl staplers, we expect that this stapling method could facilitate the design of the stapled peptide-based dual agonists suitable for oral administration.


Asunto(s)
Receptores de la Hormona Gastrointestinal , Animales , Polipéptido Inhibidor Gástrico , Receptor del Péptido 1 Similar al Glucagón/agonistas , Ratones , Péptidos/farmacología , Receptores Acoplados a Proteínas G , Receptores de la Hormona Gastrointestinal/agonistas
12.
Tetrahedron ; 932021 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-34393281

RESUMEN

We report a direct and modular method to access non-conjugated alkenyl amides containing the 8-aminoquinoline (AQ) directing auxiliary and related groups via cross-metathesis. In this way, readily available, AQ-containing, terminal ß,γ-unsaturated amides can be coupled with various terminal alkenes to furnish internal alkene products that are otherwise difficult to prepare. The value of this family of products stems from their ability to participate in a number of directed alkene functionalization reactions.

13.
Org Lett ; 23(14): 5311-5316, 2021 07 16.
Artículo en Inglés | MEDLINE | ID: mdl-34213351

RESUMEN

A nickel-catalyzed 1,2-diarylation of alkenyl ketones with aryl iodides and arylboronic esters is reported. Ketones with a variety of substituents serve as effective directing groups, offering high levels of regiocontrol. A representative product is diversified into a wide range of useful products that are not readily accessible via existing 1,2-diarylation reactions. Preliminary mechanistic studies shed light on the binding mode of the substrate, and Hammett analysis reveals the effect of electronic factors on initial rates.

14.
J Am Chem Soc ; 143(24): 8962-8969, 2021 06 23.
Artículo en Inglés | MEDLINE | ID: mdl-34077182

RESUMEN

The vicinal fluorofunctionalization of alkenes represents an expedient strategy for converting feedstock olefins into valuable fluorinated molecules and as such has garnered significant attention from the synthetic community; however, current methods remain limited in terms of scope and selectivity. Here we report the site-selective palladium-catalyzed three-component coupling of alkenylbenzaldehydes, arylboronic acids, and N-fluoro-2,4,6-trimethylpyridinium hexafluorophosphate facilitated by a transient directing group. The synthetically enabling methodology constructs vicinal stereocenters with excellent regio-, diastereo-, and enantioselectivities, forging products that map onto bioactive compounds.


Asunto(s)
Fluorocarburos/síntesis química , Paladio/química , Catálisis , Fluorocarburos/química , Estructura Molecular , Estereoisomerismo
15.
Mar Drugs ; 19(1)2021 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-33419049

RESUMEN

The high-performance liquid chromatography method coupled with diode array and mass spectrometric detector (HPLC-DAD-MS) method for quinonoid pigment identification and quantification in sea urchin samples was developed and validated. The composition and quantitative ratio of the quinonoid pigments of the shells of 16 species of sea urchins, collected in the temperate (Sea of Japan) and tropical (South-China Sea) climatic zones of the Pacific Ocean over several years, were studied. The compositions of the quinonoid pigments of sea urchins Maretia planulata, Scaphechinus griseus, Laganum decagonale and Phyllacanthus imperialis were studied for the first time. A study of the composition of the quinonoid pigments of the coelomic fluid of ten species of sea urchins was conducted. The composition of quinonoid pigments of Echinarachnius parma jelly-like egg membrane, of Scaphechinus mirabilis developing embryos and pluteus, was reported for the first time. In the case of Scaphechinus mirabilis, we have shown that the compositions of pigment granules of the shell epidermis, coelomic fluid, egg membrane, developing embryos and pluteus are different, which should enable a fuller understanding of the functions of pigments at different stages of life.


Asunto(s)
Óvulo/química , Erizos de Mar/química , Animales , Cromatografía Líquida de Alta Presión , Embrión no Mamífero , Epidermis/química , Espectrometría de Masas , Océano Pacífico , Pigmentos Biológicos , Quinonas/química , Erizos de Mar/clasificación , Erizos de Mar/crecimiento & desarrollo
16.
Angew Chem Int Ed Engl ; 59(51): 23306-23312, 2020 12 14.
Artículo en Inglés | MEDLINE | ID: mdl-32894810

RESUMEN

A nickel-catalyzed regiodivergent hydroarylation and hydroalkenylation of unactivated alkenyl carboxylic acids is reported, whereby the ligand environment around the metal center dictates the regiochemical outcome. Markovnikov hydrofunctionalization products are obtained under mild ligand-free conditions, with up to 99 % yield and >20:1 selectivity. Alternatively, anti-Markovnikov products can be accessed with a novel 4,4-disubstituted Pyrox ligand in excellent yield and >20:1 selectivity. Both electronic and steric effects on the ligand contribute to the high yield and selectivity. Mechanistic studies suggest a change in the turnover-limiting and selectivity-determining step induced by the optimal ligand. DFT calculations reveal that in the anti-Markovnikov pathway, repulsion between the ligand and the alkyl group is minimized (by virtue of it being 1° versus 2°) in the rate- and regioselectivity-determining transmetalation transition state.


Asunto(s)
Alquenos/química , Ácidos Carboxílicos/química , Hidrocarburos/síntesis química , Níquel/química , Catálisis , Teoría Funcional de la Densidad , Hidrocarburos/química , Ligandos , Estructura Molecular , Estereoisomerismo
17.
Molecules ; 25(11)2020 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-32481528

RESUMEN

Owing to their pleiotropic metabolic benefits, glucagon-like peptide-1 receptor (GLP-1R) agonists have been successfully utilized for treating metabolic diseases, such as type 2 diabetes and obesity. As part of our efforts in developing long-acting peptide therapeutics, we have previously reported a peptide engineering strategy that combines peptide side chain stapling with covalent integration of a serum protein-binding motif in a single step. Herein, we have used this strategy to develop a second generation extendin-4 analog rigidified with a symmetrical staple, which exhibits an excellent in vivo efficacy in an animal model of diabetes and obesity. To simplify the scale-up manufacturing of the lead GLP-1R agonist, a semisynthesis protocol was successfully developed, which involves recombinant expression of the linear peptide followed by attachment of a polyethylene glycol (PEG)-fatty acid staple in a subsequent chemical reaction step.


Asunto(s)
Exenatida/análogos & derivados , Exenatida/metabolismo , Receptor del Péptido 1 Similar al Glucagón/agonistas , Receptor del Péptido 1 Similar al Glucagón/metabolismo , Animales , Diabetes Mellitus Tipo 2 , Exenatida/química , Ácidos Grasos/química , Masculino , Ratones , Estructura Molecular , Obesidad , Péptidos/química , Péptidos/metabolismo , Polietilenglicoles/química
18.
Sci Adv ; 6(20): eaaz4988, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32440547

RESUMEN

Existing long α-helix mimicking necessitates the retention of most natural amino acid residues to maintain their biological activity. Here, we report the exploration of helical sulfono-γ-AApeptides with entire unnatural backbones for their ability to structurally and functionally mimic glucagon-like peptide 1 (GLP-1). Our findings suggest that efficient construction of novel GLP-1 receptor (GLP-1R) agonists could be achieved with nanomolar potencies. In addition, the resulting sulfono-γ-AApeptides were also proved to display remarkable stability against enzymatic degradation compared to GLP-1, augmenting their biological potential. This alternative strategy of α-helix mimicking, as a proof of concept, could provide a new paradigm to prepare GLP-1R agonists.


Asunto(s)
Péptido 1 Similar al Glucagón , Peptidomiméticos , Péptidos/química , Peptidomiméticos/química , Conformación Proteica en Hélice alfa
19.
Bioconjug Chem ; 31(4): 1167-1176, 2020 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-32243137

RESUMEN

Oxyntomodulin (OXM) is an intestinal peptide hormone that activates both glucagon-like peptide-1 (GLP-1) and glucagon (GCG) receptors. The natural peptide reduces body weight in obese subjects and exhibits direct acute glucoregulatory effects in patients with type II diabetes. However, the clinical utility of OXM is limited due to its lower in vitro potency and short in vivo half-life. To overcome these issues, we developed stapled, long-acting, and highly potent OXM analogs with balanced activities at both GLP-1 and GCG receptors. The lead molecule O14 exhibits potent and long-lasting effects on glucose control, body weight loss, and reduction of hepatic fat reduction in DIO mice. Importantly, O14 significantly reversed hepatic steatosis; reduced liver weight, total cholesterol, and hepatic triglycerides; and improved markers of liver function in a nonalcoholic steatohepatitis (NASH) mouse model. A symmetrical version of the peptide was also shown to be more efficacious and long-lasting in controlling glucose than semaglutide and the clinical candidate cotadutide in wild-type mice, highlighting the utility of our designs of the dual agonist as a potential new therapy for diabetes and liver diseases.


Asunto(s)
Peso Corporal/efectos de los fármacos , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Oxintomodulina/farmacología , Oxintomodulina/farmacocinética , Animales , Glucemia/metabolismo , Colesterol/sangre , Hígado/efectos de los fármacos , Hígado/metabolismo , Ratones , Enfermedad del Hígado Graso no Alcohólico/sangre , Oxintomodulina/uso terapéutico , Triglicéridos/metabolismo
20.
Angew Chem Int Ed Engl ; 59(23): 8885-8890, 2020 06 02.
Artículo en Inglés | MEDLINE | ID: mdl-32196876

RESUMEN

Metal-coordinating directing groups have seen extensive use in the field of transition-metal-catalyzed alkene functionalization; however, their waste-generating installation and removal steps limit the efficiency and practicality of reactions that rely on their use. Inspired by developments in asymmetric organocatalysis, where reactions rely on reversible covalent interactions between an organic substrate and a chiral mediator, we have developed a transient-directing-group approach to reductive Heck hydroarylation of alkenyl benzaldehyde substrates that proceeds under mild conditions. Highly stereoselective migratory insertion is facilitated by in situ formation of an imine from catalytic amounts of a commercially available amino acid additive. Computational studies reveal an unusual mode of enantioinduction by the remote chiral center in the transient directing group.


Asunto(s)
Alquenos/química , Benzaldehídos/química , Catálisis , Estereoisomerismo , Temperatura , Elementos de Transición/química
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