Fatty Diacid Research Articles

Development of Zalfermin, a Long-Acting Proteolytically Stabilized FGF21 Analog.

Here, we describe the development of the FGF21 analog zalfermin (NNC0194-0499, 15), intended for once-weekly sc dosing. Protein engineering was needed to address inherent druggability issues of the natural FGF21 hormone. Thus, deamidation of Asp121 was solved by mutation to glutamine, and oxidation of Met168 was solved by mutation to leucine. N-terminal region degradation by dipeptidyl peptidase IV was prevented by alanine residue elongation. To prevent inactivating metabolism by fibroblast activation protein and carboxypeptidase-like activity in the C-terminal region, and to achieve t1/2 extension (53 h in cynomolgus monkeys), we introduced a C18 fatty diacid at the penultimate position 180. The fatty diacid binds albumin in a reversible manner, such that the free fraction of zalfermin potently activates the FGF-receptor complex and retains receptor selectivity compared with FGF21, providing strong efficacy on body weight loss in diet-induced obese mice. Zalfermin is currently being clinically evaluated for the treatment of metabolic dysfunction-associated steatohepatitis.

802-P: Beneficial Effects of a Functionally Selective Insulin on Vascular Function and Liver Triglycerides

Selective insulin resistance, where insulin's ability to lower blood glucose via the Akt signaling pathway gradually decreases while retaining its effectiveness in activating other signaling pathways (e.g. MAPK), is a key pathophysiological mechanism underlying the hyperglycemia, dyslipidemia and vascular dysfunction in type 2 diabetes (T2D). Here we hypothesize that a selective signaling insulin analog that activates Akt signaling but has a considerably reduced effect on MAPK should counteract selective insulin resistance and provide effective glucose lowering with improved vascular function, reduced hepatic lipid accumulation and generally alleviate insulin resistance over time compared to human insulin (HI). NNC-965, a basal insulin analog with 4 amino acid modifications and a C18 fatty diacid, was designed as a functionally selective insulin, with greater Akt than MAPK activation in several cellular systems and in vivo. NNC-965 fully activates glucose regulating pathways, including inhibition of glucose output, glycogen accumulation and inhibition of gluconeogenic mRNAs in rat hepatocytes as well as stimulation of glucose uptake and inhibition of lipolysis in rat adipocytes. In contrast, NNC-965 displayed reduced induction of lipogenic mRNA and de novo lipogenesis in rat liver cells compared to HI. In a mouse model of T2D, treatment with NNC-965 for 6 weeks to the same glucose level as insulin 700 (an insulin degludec-like analog) resulted in 35% less liver triglycerides and improved acetylcholine mediated vasodilation in ex vivo studies using mesenteric arterioles. In conclusion, NNC-965 is a novel functionally selective insulin analog that can potentially improve insulin resistance and eventually reduce cardiovascular risk by restoring balanced insulin signaling. Disclosure G.S.Olsen: Employee; Novo Nordisk A/S. G.Povlen: Employee; Novo Nordisk. T.A.Pedersen: Employee; Novo Nordisk A/S. R.Slaaby: Employee; Novo Nordisk, Stock/Shareholder; Novo Nordisk. B.F.Hansen: Employee; Novo Nordisk A/S, Stock/Shareholder; Novo Nordisk A/S. T.Glendorf: Employee; Novo Nordisk A/S, Stock/Shareholder; Novo Nordisk A/S. D.Demozay: None. H.Hvid: Employee; Novo Nordisk A/S. E.Nishimura: Employee; Novo Nordisk A/S. J.Brandt: Employee; Novo Nordisk A/S.

Design of Potent and Proteolytically Stable Biaryl-Stapled GLP-1R/GIPR Peptide Dual Agonists.

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.

The effect of fatty diacid acylation of human PYY3-36 on Y2 receptor potency and half-life in minipigs

Peptides are notoriously known to display very short in vivo half-lives often measured in minutes which in many cases greatly reduces or eliminates sufficient in vivo efficacy. To obtain long half-lives allowing for up to once-weekly dosing regimen, fatty acid acylation (lipidation) have been used to non-covalently associate the peptide to serum albumin thus serving as a circulating depot. This approach is generally considered in the scientific and patent community as a standard approach to protract almost any given peptide. However, it is not trivial to prolong the half-life of peptides by lipidation and still maintain high potency and good formulation properties. Here we show that attaching a fatty acid to the obesity-drug relevant peptide PYY3-36 is not sufficient for long pharmacokinetics (PK), since the position in the backbone, but also type of fatty acid and linker strongly influences PK and potency. Furthermore, understanding the proteolytic stability of the backbone is key to obtain long half-lives by lipidation, since backbone cleavage still occurs while associated to albumin. Having identified a PYY analogue with a sufficient half-life, we show that in combination with a GLP-1 analogue, liraglutide, additional weight loss can be achieved in the obese minipig model.

Molecular Engineering of Insulin Icodec, the First Acylated Insulin Analog for Once-Weekly Administration in Humans.

Here, we describe the molecular engineering of insulin icodec to achieve a plasma half-life of 196 h in humans, suitable for once-weekly subcutaneously administration. Insulin icodec is based on re-engineering of the ultra-long oral basal insulin OI338 with a plasma half-life of 70 h in humans. This systematic re-engineering was accomplished by (1) further increasing the albumin binding by changing the fatty diacid from a 1,18-octadecanedioic acid (C18) to a 1,20-icosanedioic acid (C20) and (2) further reducing the insulin receptor affinity by the B16Tyr → His substitution. Insulin icodec was selected by screening for long intravenous plasma half-life in dogs while ensuring glucose-lowering potency following subcutaneous administration in rats. The ensuing structure-activity relationship resulted in insulin icodec. In phase-2 clinical trial, once-weekly insulin icodec provided safe and efficacious glycemic control comparable to once-daily insulin glargine in type 2 diabetes patients. The structure-activity relationship study leading to insulin icodec is presented here.

236-OR: Molecular and Biological Properties of Insulin Icodec, a New Insulin Analog Designed to Give a Long Half-Life Suitable for Once-Weekly Dosing

Insulin icodec is a novel insulin analog with a terminal elimination half-life of ∼196 hours currently in clinical development, designed to be able to cover a full week’s basal insulin requirements with a single subcutaneous injection. To attain such a long half-life, the insulin molecule was modified to achieve an albumin-bound circulating depot of icodec which acts just as human insulin (HI) but is more slowly cleared.Addition of a C20 fatty diacid containing side chain at B29K via a hydrophilic linker imparts strong but reversible albumin binding (10x that of insulin detemir). Three amino acid substitutions (A14E, B16H and B25H) ensure reduced enzymatic degradation of icodec and contribute to attenuating insulin receptor (IR) binding and clearance, further prolonging the half-life. In vitro studies demonstrated that icodec is a specific and full agonist of the human IR, and that it displays the same dose-dependent mode of action as HI, exemplified by its ability to phosphorylate the IR and stimulate intracellular signaling pathways (phospho-AKT and -ERK). Functional assays have demonstrated that icodec elicits the same pattern of metabolic effects as HI, including glucose uptake and lipogenesis in fat cells, and stimulation of glycogen synthesis in liver cells. The affinity of icodec for the IGF-1 receptor was found to be proportionately lower than its binding to the IR. The in vitro mitogenic effect of icodec in primary human mammary cells (HMEC), as well as in mammary and colon carcinoma cells (MCF-7 and COLO 205) was found to be low relative to that of HI. In conclusion, icodec is a new insulin analog designed to achieve a slowly cleared, albumin-bound circulating depot which results in a long half-life suited for once weekly injections, covering the basal insulin requirements for a full week. *Insulin icodec (proposed INN). Disclosure E. Nishimura: Employee; Self; Novo Nordisk A/S. Stock/Shareholder; Self; Novo Nordisk A/S. Stock/Shareholder; Spouse/Partner; Novo Nordisk A/S. T. Kjeldsen: Employee; Self; Novo Nordisk A/S. Stock/Shareholder; Self; Novo Nordisk A/S. Stock/Shareholder; Spouse/Partner; Novo Nordisk A/S. F. Hubalek: Employee; Self; Novo Nordisk A/S. Stock/Shareholder; Self; Novo Nordisk A/S. T. Glendorf: Employee; Spouse/Partner; Novo Nordisk A/S. Employee; Self; Novo Nordisk A/S. Stock/Shareholder; Spouse/Partner; Novo Nordisk A/S. Stock/Shareholder; Self; Novo Nordisk A/S. C.E. Stidsen: Employee; Self; Novo Nordisk A/S. Stock/Shareholder; Self; Novo Nordisk A/S. B.F. Hansen: Stock/Shareholder; Self; Novo Nordisk A/S. T.A. Pedersen: Employee; Self; Novo Nordisk A/S. A. Luetzen: Employee; Self; Novo Nordisk A/S. Stock/Shareholder; Self; Novo Nordisk A/S. L. Pridal: None. P. Madsen: Employee; Self; Novo Nordisk A/S.

New amino acid based biodegradable poly(ester amide)s via bis-azlactone chemistry

Three new classes of the amino acid based biodegradable (AABB) polymers were synthesized via step growth polymerization of bis-azlactones and amino acid based diamine-diesters with activated fatty diester and alkylenediamine: a) poly(ester amide)s (PEAs) were obtained by polymerization of bis-azlactones with diamine-diesters, b) hydrophobically modified co-poly(ester amide)s (co-PEAs) were synthesized by copolymerization of activated fatty diacid diester and bis-azlactones with diamine-diesters, and c) poly(ester amide-co-amide)s (PEA-co-PAs) were obtained by copolymerization of alkylene diamine and diamine-diesters with bis-azlactones. The new poly(ester amide)s showed relatively low-molecular-weights (Mw within 2,800–19,600 Da, GPC in DMF), whereas the new co-poly(ester amide)s and poly(ester amide-co-amide)s exhibited high-molecular-weights (Mw within 40–100 kDa) leading to good mechanical properties. Incorporation of the bis-azlactone fragments into the poly(ester amide)s backbone increased hydrophobicity and thermal stability, whereas incorporation of diamine-diester units into the backbone of the bis-azlactone based polyamides rendered them biodegradable. Synthesized AABB polymers are potential candidates for constructing resorbable surgical and pharmaceutical devices.

Compositional analysis of Scottish honeys with antimicrobial activity against antibiotic-resistant bacteria reveals novel antimicrobial components

Antibiotic-resistant bacteria are a major health concern and honey may provide an alternative to antibiotic use under certain conditions. The antimicrobial action of six Scottish honeys and Manuka Medihoney® was compared against antibiotic-resistant Acinetobacter calcoaceticus, Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli. Certain Scottish honeys, such as Highland and Portobello honey 2011, were comparable in effectiveness to the established antimicrobial Medihoney®, inhibiting growth to <1 compared to 10 log10 CFU/ml in the control. Heather honey was the next most active while Blossom honeys were less active. Bacteria were inhibited by a sugar-matched control, but to a lesser extent, indicating that antimicrobial activity was associated with non-sugar components, such as polyphenols. However, total phenol content or antioxidant capacity did not correlate with antimicrobial activity. Liquid chromatography-mass spectrometric analysis revealed that the composition of polyphenol and non-polyphenol components differed between honeys. In addition, candidate components that could be associated with antimicrobial activity were noted including novel fatty diacid glycoside derivatives not previously identified in honeys.

Degludec: the new ultra-long insulin analogue.

The development of extended-action insulin analogues was motivated by the unfavorable pharmacokinetic (PK) profile of the conventional long-acting insulin formulations, generally associated with marked inter and intra patient variability and site- and dose-dependent effect variation. The new ultra-long insulin analogue degludec (IDeg) has the same amino acid sequence as human insulin except for the removal of threonine in the position 30 of the B chain (Des-B30, “De”) and the attachment, via a glutamic acid linker (“glu”), of a 16-carbon fatty diacid (hexadecanoic diacid, “dec”) to lysine in the position 29 of the B chain. These modifications allow that, after changing from the pharmaceutical formulation to the subcutaneous environment, IDeg precipitates in the subcutaneous tissue, forming a depot that undergoes a highly predictable gradual dissociation. Thus, once-daily dosing of IDeg results in a low peak: trough ratio, with consequent low intra-individual variability and plasmatic concentrations less critically dependent upon the time of injections. The clinical development program of IDeg (BEGIN) was comprised of 9 therapeutic confirmatory trials of longer duration (26–52 weeks) and showed that the efficacy of IDeg is comparable to insulin glargine in type 1 (T1D) and type 2 (T2D) diabetes patients across different age, body mass index and ethnic groups. This new ultra-long insulin analogue presents as advantages flexibility in dose timing and lower risk of hypoglycemia.

Highly anisotropic thermal expansion in molecular films of dicarboxylic fatty acids

Angstrom-resolution x-ray measurements reveal the existence of two-dimensional (2D) crystalline order in molecularly thin films of surface-parallel-oriented fatty diacid molecules supported on a liquid mercury surface. The thermal expansion coefficients along the two unit cell vectors are found to differ 17-fold. The high anisotropy of the 2D thermal expansion and the crystalline coherence length are traced to the different bonding in the two directions: van der Waals normal to, and covalent plus hydrogen bonding along the molecular backbone axis. Similarities with, and differences from, negative thermal expansion materials are discussed.

New Unsaturated Biodegradable Poly(ester amide)s Composed of Fumaric Acid, L-leucine and α,ω-Alkylene Diols

The synthesis of α-amino acid L-leucine (Leu) based high-molecular-weight and biodegradable unsaturated poly(ester-amide)s (PEAs) was reported. Amino acid L-phenylalanine (Phe) was used to synthesize some copolymers for a comparative study. The syntheses of three types of new unsaturated PEA polymers were explored – (i) Unsaturated PEA homopolymers (UPEAs) composed of fumaric acid, aliphatic diol and one alpha-amino acid: L-Leu or L-Phe; (ii) L-Leu-based unsaturated-saturated copolymers (USPEAs) composed of aliphatic diol, fumaric and saturated fatty diacid, and (iii) L-Leu- and L-Phe-based copolymers (co-UPEAs) composed of 100% fumaric acid, aliphatic diol and combinations of both amino acids. Many of the targeted unsaturated polymers were soluble in common organic solvents and showed good film-forming property. The unsaturated PEA polymers were further chemically modified into functional derivatives and subjected to thermal and photochemical transformations (curing) that substantially expand material properties and, hence, the scopes of potential applications as absorbable surgical devices and drug carriers.

Three new lipids from the seeds of Trogopterus xanthipes

Chemical investigation of Feces Trogopterus ( Trogopterus xanthipes) has led to the isolation of three new lipids, including two new cerebrosides, 1- O-β-D-glucopyranosyloxy)-(2 S,3 S,4 R,6 E)-2-[(2′ R)-2′-hydroxyheptadecanoylamino]-8-heptadecene-3,4-diol (1) and 1- O-β-D- glucopyranosyloxy)-(2 S,3 S,4 R,6 E)-2-[(2′ R)-2′-hydroxy-heptadecanoylamino]-8-nonadecene-3,4-diol (2), and one new fatty acid ester, bis(2,3-dihydoxypropyl)-tetracosanedioate (3). Their structures were elucidated by chemical and spectral means. This is the first report on the occurrence of cerebroside and fatty diacid diester in Feces Trogopterus.

Ethylenediamine tetraacetic acid modification of crosslinked chitosan designed for a novel metal‐ion adsorbent

AbstractNovel chitosan‐based adsorbent materials were synthesized with a higher fatty diacid diglycidyl as a crosslinking agent, and the adsorption ability of the resulting polymers for several metal ions was evaluated. Selective adsorption for Cu2+ in comparison with other divalent metal ions, such as Ni2+, Pb2+, Cd2+, and Ca2+, was observed with the crosslinked chitosan sorbent at pH 6; however, the adsorption power decreased abruptly as the pH value of the solution decreased. The addition of ethylenediamine tetraacetic acid (EDTA) residues to crosslinked chitosan significantly enhanced the adsorption power for metal ions, especially for Ca2+. The adsorptivity of Ca2+ was dramatically improved with the introduction of EDTA residues, and the value was greater than that obtained with a commercial chelate resin (CR11). Although the adsorption power of the EDTA‐derivatized sorbent for other metal ions was just comparable to that of the CR11 material, the newly synthesized adsorbent could be used for the recovery of metal ions from industrial waste solutions with a relatively wide range of pHs, from 4.0 to 6.0. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2758–2764, 2004

Synthesis of Novel Crosslinked Chitosans with a Higher Fatty Diacid Diglycidyl and Their Adsorption Abilities towards Acid Dyes

Novel chitosan-based adsorbent materials with a higher fatty diacid diglycidyl as the crosslinking agent were synthesized and the adsorption abilities of the resulting polymers evaluated towards typical acid dyes. The successful formation of a crosslinked structure was confirmed via infrared spectroscopic measurements and the solubility of the polymer towards 10% aqueous solutions of acetic and formic acids determined. At higher dye concentrations, the adsorption abilities of the crosslinked chitosan towards hydrophilic CI Acid Orange 7 and CI Acid Red 1 increased with decreasing degree of substitution. However, at lower dye concentrations, the crosslinked chitosan with the lowest degree of substitution exhibited the lowest adsorption capability. With such hydrophilic acid dyes, the extent of adsorption decreased significantly as the pH of the solution increased. On the other hand, CI Acid Red 138, which contains a dodecyl group in the chemical structure, was adsorbed to a considerable extent even at higher pH values, suggesting hydrophobic interaction between the alkyl group in the dye molecule and the hydrophobic crosslinker.

Acetylenic acids from the aerial parts of Nanodea muscosa.

The aerial parts of Nanodea muscosa, collected in Chile, yielded two new acetylenic acids. Their structures were elucidated by spectroscopic analyses, including 2D NMR techniques, as (13E)-octadec-13-en-11-ynoic acid (1) and (2E)-octadec-2-en-4-ynedioic acid (2). Compound 2 constitutes the first example of a conjugated ene-yne fatty diacid isolated from a natural source. Compounds 1 and 2 did not exhibit toxicity toward a panel of DNA damage checkpoint defective yeast mutants or show affinity for the 5-HT(1A), 5-HT(2A), D(2), and H(1) receptors.

Synthesis and properties of biodegradable copolymers based on polyether oligomers and fatty diacids

Polyether oligomers (Mn = 200–2000) were respectively esterified by succinic anhydride and fatty sebacoyl chloride to synthesize corresponding intermediate diacids, and experimental results of melt polycondensations based on these two kinds of intermediates were compared. The reasons for affecting higher molecular weight products to be achieved in polymerization with prepolymers based on succinic anhydride esterification were theoretically analyzed. Light scattering measurements showed that copolyanhydrides with higher molecular weights exceeding 8 × 104 (weight-average) were synthesized from the intermediate diacids prepared by a new method using fatty diacid chlorides to undergo esterification with polyether. Synthesized intermediates were characterized by 1H-NMR and infrared spectroscopy. Intrinsic viscosity of the polymers were measured to display the advancement of polymerization. The properties of polymers were investigated by X-ray diffraction and differential scanning calorimetry analysis as well. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 66: 1891–1898, 1997

Nonlinear biodegradable polyanhydrides synthesized from natural fatty acids through a new way

Ricinoleic acid was esterified by fatty diacid chlorides to yield intermediate diacids, which were next converted to corresponding polyanhydrides by vacuum-melt polycondensation. The intermediates and polymers were characterized by means of 1H NMR, IR spectroscopy, differential scanning calorimetry (DSC), X-Ray diffraction and light scattering. The optimized reaction conditions of melt polycondensation were investigated and copolyanhydride with molecular weight (weight average) up to 1.38×105 and intrinsic viscosity of 126 cm3/g was obtained. DSC and X-ray diffraction analysis showed that the synthesized copolyanhydrides exhibited much lower crystallinity and improved thermal properties in comparison with aliphatic linear homopolyanhydrides.

Cytochrome P450BM-3 (CYP102): regiospecificity of oxidation of omega-unsaturated fatty acids and mechanism-based inactivation.

Cytochrome P450BM-3 preferentially oxidized fatty acids with terminal double or triple bonds to the omega-2 hydroxylated fatty acids rather than, respectively, to the epoxide or diacid metabolites. The enzyme is inactivated during catalytic turnover of long, terminally unsaturated fatty acids but not by the analogous medium-length fatty acids. Enzyme inactivation by 17-octadecynoic acid and 16-hydroxy-17-octadecynoic acid is due to alkylation of the prosthetic heme group to given an adduct tentatively identified as N-(2-oxo-3-hydroxy-17-carboxyheptadecyl)protoporphyrin IX by its chromatographic and spectroscopic properties. Catalytic turnover of 17-octadecenoic acid also results in heme modification. Fatty diacid monoethyl thioesters are introduced as a new class of irreversible inhibitors that exploit the omega-2 oxidation specificity of cytochrome P450BM-3. Catalytic oxidation of the monoethyl thioesters of dodecanedioic and hexadecanedioic acids results in enzyme inactivation and formation of the parent diacids as metabolites. Limited tryptic digestion of the enzyme after incubation with the monoethyl thioester of [14C]hexadecanedioic acid shows that the inactivating agent binds covalently to both the heme and flavin domains. This finding, and the observation that glutathione prevents inactivation of the enzyme by the monoethyl thioesters, indicate that a diffusible metabolite, probably the sulfoxide, is responsible for enzyme inactivation. The strong preference for omega-2 allylic or propargylic hydroxylation over terminal pi-bond oxidation is opposite to the usual cytochrome P450 pattern and requires that the enzyme actively suppress terminal pi-bond oxidation. The inference that the enzyme binds and sequesters the terminal carbon in a lipophilic pocket is consistent with the crystal structure of the hemoprotein domain of cytochrome P450BM-3.