Background/Objectives: Understanding metabolic adaptations in long-livers provides critical insights into the biochemical mechanisms underlying extreme longevity. While many long-livers maintain metabolic stability, others exhibit significant metabolic alterations, potentially linked to age-related diseases. This study aims to identify distinct metabolic signatures in long-livers and their associations with clinical outcomes, particularly cardiovascular disease. Methods: We analyzed serum samples from 53 oldest long-livers (mean age 98.2 ± 2 years) using liquid chromatography–tandem mass spectrometry (LC-MS/MS) to identify metabolic alterations and gathered clinical data to link the detected metabolic changes with phenotypes. Results: Using Welch’s t-test with Benjamini–Hochberg FDR correction (q < 0.01, |log2FC| > 2), we identified 15 significantly altered metabolites distinguishing a subgroup of 6 long-livers from 47 metabolically stable individuals. This metabolically altered subgroup exhibited striking elevations in key metabolites, including L-serine (log2FC = 8.05, >250-fold increase, q = 1.26 × 10−8), D-galactose (log2FC = 6.86, 116-fold, q = 8.87 × 10−7), butyric acid (log2FC = 6.24, 75-fold, q = 9.79 × 10−5), and choline (log2FC = 6.11, ~69-fold, q = 5.45 × 10−7), with enrichment in the butyric acid metabolism pathway. Post hoc power analysis confirmed >80% power for all significant metabolites with very large effect sizes (Cohen’s d > 2.0). Conclusions: Our findings reveal substantial metabolic heterogeneity among long-livers, with a distinct subgroup exhibiting profound metabolic alterations and clinical features associated with cardiovascular and systemic disease. These results highlight that the butyric acid pathway may contribute to age-related disease survival in extreme aging.

Modern advances in molecular vitaminology are characterized by a marked expansion in understanding­ the molecular mechanisms underlying the actions of vitamins and their biologically active derivatives as highly effective compounds that ensure controlled interactions between cellular regulatory systems and metabolic processes. The molecular mechanisms of the pleiotropic effects of the hormonally active form of vitamin D3, calcitriol (1α,25(OH)2D3), are realized in target tissues through vitamin D3 receptors (VDR), which are present in virtually all cells. Our studies have focused on VDR-mediated effects, including modulation of the transcriptional activity of NF-κB, NFAT, HIF-1 and PPAR, as well as involvement of regulatory pathways such as HIF-1α/VEGF and RANK/NF-κB. We have also examined signaling through glucocorticoid and mine­ralocorticoid receptors, which play a key role in the antioxidant, anti-inflammatory, and anti-apoptotic effects of vitamin D3 under normal conditions and in pathology (osteoporosis, neurodegenerative disorders associated with glucocorticoid-induced neurotoxicity and type 2 diabetes mellitus). The mechanisms of the neurotropic effects of vitamin B3 (nicotinamide) and a derivative of nicotinic and amino butyric acid, nicotinoil-GABA (N-GABA), have also been studied. It has been demonstrated that nicotinamide (NAm) inhibits the development of diabetic neuropathy by reducing the activity and level of the PARP-1 enzyme, suppressing its fragmentation and preventing DNA damage in the brain tissue, and normalizing the nuclear levels of SIRT1 and SIRT2 proteins in neurons. One of the effective methodological approaches in our studies has been the investigation of thiamine-binding proteins in the brain and the effects of thiamine deficiency on the expression and state of neurospecific proteins. Based on our findings, we have formulated a working hypothesis regarding­ the molecular mechanisms of vitamin B1 involvement in the functioning of the cholinergic component of the nervous system. This hypothesis suggests that, in addition to the pool of thiamine diphosphate (ThDP) that binds to ThDP-dependent enzymes, nerve cells contain a rapidly exchangeable pool of thiamine derivatives that are involved in acetylcholine metabolism. The research achievements of our Department demonstrate the therapeutic potential of vitamins D3, B3, B1, and their biologically active derivatives in preventing the develop­ment of neurodegenerative complications under various pathological conditions and provide a scientific basis for the development of novel vitamin supplements. Keywords: diabetes mellitus, glucocorticoids, inflammation, neurodegeneration, neurospecific proteins, nicotinoyl-GABA, oxidative stress, thiamine binding proteins, thiamine diphosphate, transcription factors, vitamin B(1), vitamin B3, vitamin D3

Blackground/Objectives: Tributyrin (TB), a stable derivative of butyric acid, has been widely used in animal feeds for its health-promoting effects. This study evaluated the efficacy of dietary TB serving as a functional feed additive in enhancing intestinal health of mandarin fish (Siniperca chuatsi), with a focus on elucidating the associated molecular mechanisms. Methods: A total of 300 juvenile mandarin fish (200.0 ± 5.2 g) were randomly assigned to one of three dietary groups: a control group (0 mg/kg TB), a low-dose TB group (TB1, 500 mg/kg), or a high-dose TB group (TB2, 1000 mg/kg). The one-month feeding trial was conducted under strictly controlled conditions, with water quality maintained within optimal range. Fish were fed their respective diets twice daily to apparent satiety. Results: Results showed that TB supplementation significantly increased villus height in the mid- and hindgut, with the TB2 group showing the most pronounced improvement. Furthermore, transcriptome analysis revealed that TB altered the expression of genes involved in energy metabolism, fatty acid oxidation, and steroid biosynthesis pathways. Notably, TB supplementation up-regulated key genes such as gls2b (energy metabolism) and cpt1b (fatty acid oxidation), and modulated especially modulated steroid biosynthesis through genes sqlea and dhcr24h. Co-expression network analysis further identified hub genes associated with energy metabolism (etfb), immune regulation (il20ra, foxp1b), and cell cycle regulation (cdc20, ccnb1). Conclusions: These findings elucidate the mechanism of action of TB as a functional feed additive, providing a theoretical foundation for its application in aquaculture to enhance intestinal health.

Tributyrin enhances growth and intestinal health in green mud crab (Scylla paramamosain) through butyrate-driven metabolic regulation.

Solid state graphene sensors combine sensitivity achieved by conductance modulation, selectivity achieved by incorporation of moieties that selectively adsorb target analytes, and stability by immobilization of these selective adsoprtion sites. Simultaneously improving sensitivity and selectivity is a critical challenge. For example, many graphene biomolecular sensors use non-covalent linkers, such as pyrene butyric acid derivatives (PBA) that rely on non-covalent π-π stacking to bind selective adsorption sites to the graphene sensor. As another example, graphene ion sensitive field effect transistors (ISFETs) rely on ion adsorption moieties adsorbed within a polymer matrix with lipophilic salts providing ion exchange. These approaches give imperfect immobilization, contributing to sensor variance and drift.In turn, covalent binding of selective adsorption moeities is anticipated to improve immobilization and stability, but electronic conduction is significantly diminished by the disruption of graphene's π conjugation by covalent attachement. For example, hydrogenation, fluorination, and aryl diazonium functionalization all induce insulating behaviour in graphene monolayers. There is a need, therefore, to find a means to covalently immobilize selective adsorption sites at the graphene surface whilst preserving π-conjugation and electronic conduction.I will review progress in two new avenues that address this challenge: aryl-diazonium functionalization of bilayer graphene, and divalent functionalization of monolayer graphene. In the former case, one layer of a bilayer is functionalized by aryl-diazonium while the π-conjugation and electronic conduction of the second layer is preserved. In the latter case, divalent modification of monolayer graphene entails adducts that bind to two adjacent carbon atoms on the lattice, such as carbene and nitrene species. This approach is inspired by experiments suggesting the preservation of π-conjugation and electronic conduction in single walled carbon nanotubes. Experimental results on the spectroscopy and charge transport properties of aryl-diazonium functionalized bilayer graphene and carbene and nitrene functionalized monolayer graphene will be presented. The implications for graphene sensor development will be discussed.

Phenylalanine butyramide (FBA) is a novel butyric acid derivative with favorable sensory properties, which has broad prospects in medicine and feed processing. However, there is currently limited research on the enzymatic synthesis of FBA. As is well known, lipase plays a crucial role in amide bond synthesis, but it typically requires completely anhydrous conditions. The lipase from Sphingomonas sp. HXN-200 (SpL) is the only intracellular lipase identified to date, capable of catalyzing the ammonolysis of esters or acids in an aqueous phase. In this study, we developed a method for the synthesis of FBA catalyzed by SpL in a biphasic reaction system of water and n-hexane. SpL was successfully expressed in E. coli BL21, and the optimal induction conditions were 0.4 mM IPTG and 18 h. It was ascertained that the n-hexane system containing 2% water was conducive to the reaction. Under optimized reaction conditions, 0.89 mg/mL of FBA was obtained within 15 h at 30 °C. Additionally, we found that SpL also has the ability to hydrolyze amides in the reaction of SpL catalyzing the formation of amides, so we further analyzed its catalytic mechanism.

Abstract Artificial metalloenzymes (ArMs) are an attractive approach to achieving “new to nature” biocatalytic transformations. In this work, a novel copper‐dependent artificial Michaelase (Cu_Michaelase) comprising a genetically encoded copper‐binding ligand, i. e. (2,2‐bipyridin‐5‐yl)alanine (BpyA), was developed. For the first time, such an ArM containing a non‐canonical metal‐binding amino acid was successfully optimized through directed evolution. The evolved Cu_Michaelase was applied in the copper‐catalyzed asymmetric addition of 2‐acetyl azaarenes to nitroalkenes, yielding various γ‐nitro butyric acid derivatives, which are precursors for a range of high‐value‐added pharmaceutically relevant compounds, with good yields and high enantioselectivities (up to &gt;99 % yield and 99 % ee). Additionally, the evolved variant could be further used in a preparative‐scale synthesis, providing chiral products for diverse derivatizations. X‐ray crystal structure analysis confirmed the binding of Cu(II) ions to the BpyA residues and showed that, in principle, there is sufficient space for the 2‐acetyl azaarene substrate to coordinate. Kinetic studies showed that the increased catalytic efficiency of the evolved enzyme is due to improvements in apparent K M for both substrates and a notable threefold increase in apparent k cat for 2‐acetyl pyridine. This work illustrates the potential of artificial metalloenzymes exploiting non‐canonical metal‐binding ligands for new‐to‐nature biocatalysis.

Artificial metalloenzymes (ArMs) are an attractive approach to achieving "new to nature" biocatalytic transformations. In this work, a novel copper-dependent artificial Michaelase (Cu_Michaelase) comprising a genetically encoded copper-binding ligand, i. e. (2,2-bipyridin-5-yl)alanine (BpyA), was developed. For the first time, such an ArM containing a non-canonical metal-binding amino acid was successfully optimized through directed evolution. The evolved Cu_Michaelase was applied in the copper-catalyzed asymmetric addition of 2-acetyl azaarenes to nitroalkenes, yielding various γ-nitro butyric acid derivatives, which are precursors for a range of high-value-added pharmaceutically relevant compounds, with good yields and high enantioselectivities (up to >99 % yield and 99 % ee). Additionally, the evolved variant could be further used in a preparative-scale synthesis, providing chiral products for diverse derivatizations. X-ray crystal structure analysis confirmed the binding of Cu(II) ions to the BpyA residues and showed that, in principle, there is sufficient space for the 2-acetyl azaarene substrate to coordinate. Kinetic studies showed that the increased catalytic efficiency of the evolved enzyme is due to improvements in apparent KM for both substrates and a notable threefold increase in apparent kcat for 2-acetyl pyridine. This work illustrates the potential of artificial metalloenzymes exploiting non-canonical metal-binding ligands for new-to-nature biocatalysis.

Abstract Porcine small intestinal epithelial cell line (IPEC-J2) is a good research model exploring the impact of feed additives on intestinal epithelial cells. Monobutyrin (MB), as a derivative of butyric acid (BA), overcomes the shortcomings of BA. MB can maintain intestinal barrier function in animals, but its underlying regulatory mechanism is unknown. Thus, we used IPEC-J2 cells as the research object. We were using real-time fluorescence quantitative PCR, western blot, immunofluorescence, and transcriptomics technology to explore the effect of MB on the barrier function of IPEC-J2 cells and its regulatory mechanism. The results found that MB treatment could cause IPEC-J2 cells to occur a response to hypoxia at the transcriptional level, thereby increasing the expression of hypoxia-inducible factor 1 and phospho-extracellular signal-regulated kinase 1/2 protein and improving the expression of tight junction proteins. Therefore, MB can alleviate the activation of the NF-κB signaling pathway. In addition, MB mitigates the damage to cell transmembrane glycoproteins, microvilli, and tight junctions caused by lipopolysaccharides (LPS) stimulation, thus resisting the effects of LPS. As a dietary supplement, MB has good application prospects in maintaining the intestinal epithelial barrier function of animals.

The present work describes the protolytic properties and in vitro biological activity of spinorphin (Leu-Val-Val-Tyr-Pro-Trp-Thr) and three spinorphin derivatives containing butyric acid residue: Butyryl-Lys-Lys-Leu-Leu-Val-Tyr-Pro-Trp-Thr, Butyryl-Lys-Lys-Leu-Val-Val-Tyr-Pro-Trp-Thr (butyric acid bound to the α-amino group of lysine), Lys(Butyryl)-Lys-Leu-Val-Val-Tyr-Pro-Trp-Thr (butyric acid bound to the ε-amino group of lysine) in an aqueous solution. The overall protonation constants and the stepwise dissociation constants of the ligands studied were calculated by the potentiometric method. The percentage of each species formed was estimated from the species distribution curves as a function of pH. The biological activity of all tested compounds was characterized in vitro, in the neutral red uptake and Griess assay tests in RAW264.7 macrophage cell line. The three protonation constants for spinorphin and four for its derivatives suggest that metal ions may bind to these peptides and form complexes by coordination with the functional groups of the respective amino acid residues. In vitro biological activity tests suggest that two peptides deserve attention for their potential anti-inflammatory role.

A new series of some novel substituted aryl and aliphatic -amino acid analogues of pregabalin have been synthesized by reacting substituted aromatic and aliphatic aldehydes with dimethyl malonate, di-n-propyl amine and sodium cyanide to yield substituted 4-amino-3-phenyl butyric acid derivatives, 3-amino methyl-4-methyl pentanoic acid and 3-amino methyl-hexanoic acid respectively using streckar synthesis.All the compounds were characterized by physical and spectral data.These compounds were screened for anticonvulsant activity, compound 2 was found to posess significant anticonvulsant activity at the tested concentrations when compared with that of standard and the remaining compounds showed moderate activity.These compounds can be further exploited to get the lead compound.

ω-(3-Trifluoromethylpyrazol-4-yl)alkanoic acids via (3 + 2)-cycloaddition of nitrile imines with cyclic enones and deacylative aromatization

Visible-light-driven photocatalysis for the sustainable synthesis of (±)-pregabalin using carbon nitride from melamine-cyanuric acid complex

Multicomponent radical polar crossover (RPC) reactions are useful for leveraging both radical and polar bond-forming steps to rapidly build molecular complexity in a single transformation. However, multicomponent RPC reactions that utilize carbonyl π-bond electrophiles are underrepresented in the literature. Herein, we describe a mild, photoredox-catalyzed decarboxylative multicomponent RPC reaction that couples carboxylic acids, Michael acceptors, and carbonyl electrophiles for the formation of diversely functionalized γ-amino butyric acid derivatives. This transformation also facilitates the synthesis of complex and biologically relevant γ-lactam compounds.

Lewis acid catalyzed tandem activation of the two smallest carbocycles, 3-ethoxy cyclobutanones, and donor-acceptor cyclopropanes has been demonstrated. The diphenyl-substituted 3-ethoxy cyclobutanone rearranges itself by intramolecular cyclization for the in situ generation of 1-phenyl 2-naphthol, which further undergoes remote site-selective Friedel-Crafts alkylation with donor-acceptor cyclopropane to synthesize a series of γ-naphthyl butyric acid derivatives. Further control experiments for mechanistic investigations and synthetic applications have also been carried out.

MgI2-catalyzed nucleophilic ring-opening reactions of donor-acceptor cyclopropanes with indoline-2-thiones as easy-to-handle sulfur nucleophiles were investigated. A series of functionalized γ-indolylthio butyric acid derivatives were synthesized in good to excellent yields under mild reaction conditions. Furthermore, the thioether functionalized ring-opening products could be transformed to sulfone and methionine analogues.

Insulinomas are neuroendocrine tumors that are derived from pancreatic β-cells, and they often overexpress the glucagon-like peptide-1 receptor (GLP-1R). Radiolabeled exendin-4 derivatives have been used to noninvasively detect the GLP-1R during the diagnosis and preoperative localization of insulinomas; however, their marked renal accumulation can hinder the imaging of pancreatic tail lesions. In this study, we designed and synthesized 111In-labeled exendin-4 derivatives that possessed 4-(4-substituted phenyl)-moieties as albumin binder (ALB) moieties ([111In]In-E4DA2-4), and studied their structure-activity relationships and pharmacokinetics (as well as those of [111In]In-E4DA1, which we previously reported) to determine their usefulness as radioligands for GLP-1R imaging. 111In-labeling was performed by reacting maleimide precursors with [111In]InCl3 in 2-(N-morpholino)ethanesulfonic acid buffer, and then, the products were conjugated with exendin-4-Cys40. A saturation binding assay using GLP-1R-expressing INS-1 cells was carried out to evaluate the in vitro affinity of the radioligands for the cells. In addition, the affinity of the 111In-labeled derivatives for human serum albumin (HSA) was evaluated in an HSA-binding assay. Furthermore, an in vivo biodistribution study and single-photon emission computed tomography (SPECT) imaging were performed using INS-1 tumor-bearing mice. [111In]In-E4DA1-4 were prepared at radiochemical yields of 6-17%. In the saturation binding assay, [111In]In-E4DA1-4 showed a similar affinity for the INS-1 cells, indicating that the kind of ALB moiety used had no effect on the affinity of the exendin-4 derivatives for the cells. In the HSA-binding assay, [111In]In-E4DA1-4 all bound to HSA. In the biodistribution assay, [111In]In-E4DA1-4 exhibited marked tumor accumulation and retention. In addition, they showed lower renal accumulation than previously reported exendin-4-based radioligands without ALB moieties. The pharmacokinetics of the 111In-labeled exendin-4 derivatives varied markedly according to the kind of ALB moiety used. In particular, [111In]In-E4DA2, which contained a 4-(4-bromophenyl)butyric acid derivative as an ALB moiety, showed the highest tumor accumulation. SPECT imaging with [111In]In-E4DA2 clearly visualized INS-1 tumors with no marked accumulation in normal organs. These results provide important information that will aid the design of novel exendin-4-based radioligands targeting the GLP-1R.

P200. Application of different butyric acid derivatives in weaning piglets

Insulinomas are neuroendocrine tumors that are mainly found in the pancreas. Surgical resection is currently the first-line treatment for insulinomas; thus, it is vital to preoperatively determine their locations. The marked expression of the glucagon-like peptide-1 receptor (GLP-1R) is seen in pancreatic β-cells and almost all insulinomas. Radiolabeled derivatives of exendin-4, a GLP-1R agonist, have been used with nuclear medicine imaging techniques for the in vivo detection of the GLP-1R; however, their marked renal accumulation can hinder the imaging of pancreatic tail lesions. To develop a GLP-1R imaging probe that exhibits reduced renal accumulation, we designed and synthesized a straight-chain GLP-1R-targeting radioligand, [111In]In-E4DA1, which consisted of exendin-4, DOTADG (a chelator), and an (iodophenyl)butyric acid derivative (an albumin binder [ALB]). We performed preclinical evaluations of [111In]In-E4DA1 to investigate its utility as a GLP-1R imaging probe. [111In]In-E4DA1 and [111In]In-E4D (a control compound lacking the ALB moiety) were prepared by reacting the corresponding precursors with [111In]InCl3 in buffer. Cell-binding and human serum albumin (HSA)-binding assays were performed to assess the in vitro affinity of the molecules for INS-1 (GLP-1R-positive) cells and albumin, respectively. A biodistribution assay and single-photon emission computed tomography imaging were carried out using INS-1 tumor-bearing mice. In the cell-binding assay, [111In]In-E4DA1 and [111In]In-E4D exhibited in vitro binding to INS-1 cells. In the HSA-binding assay, [111In]In-E4DA1 bound to HSA, while [111In]In-E4D showed little HSA binding. The in vivo experiments involving INS-1 tumor-bearing mice revealed that the introduction of an ALB moiety into the DOTADG-based exendin-4 derivative markedly increased the molecule's tumor accumulation while decreasing its renal accumulation. In addition, [111In]In-E4DA1 exhibited greater tumor accumulation than renal accumulation, whereas previously reported radiolabeled exendin-4 derivatives demonstrated much higher accumulation in the kidneys than in tumors. These results indicate that [111In]In-E4DA1 may be a useful GLP-1R imaging probe, as it demonstrates only slight renal accumulation.

Cytotoxic effects of butyric acid derivatives through GPR109A receptor in Colorectal Carcinoma cells by in silico and in vitro methods