Therapeutic peptides have played a huge role in chemotherapy due to their excellent biological activity and biocompatibility. However, therapeutic peptides are vulnerable to enzymatic digestion, which makes them with fast elimination in vivo. Nowadays, peptides self-assembly has become a powerful strategy for constructing nanostructures to boost their stability and bioactivity in vivo. To our knowledge, host-guest interaction-instructed in situ peptides self-assembly for biomedical applications is still rare. Herein, we intended to develop a supramolecular complex (CB[7]-FFYSV) based on the host-guest interactions between cucurbit[7]uril (CB[7]) and N-terminal aromatic residues of a therapeutic peptide (Phe-Phe-Tyr-Ser-Val, FFYSV). CB[7]-FFYSV can release therapeutic peptide FFYSV under the competition of endogenous tumor biomarker spermine (SPM) and then FFYSV can self-assemble in situ with the formation of nanofibers for enhancing tumor treatment. CB[7]-YSV without the self-assembly ability is the control group. The stability of FFYSV was obviously improved under proteinase K after encapsulation by CB[7]. CB[7]-YSV or CB[7]-FFYSV exhibited more significant toxicity to A549 and 4T1 cells with high expression of SPM than YSV or FFYSV. CB[7]-FFYSV is more effective than CB[7]-YSV due to the self-assembly of FFYSV with the formation of dense short nanofibers with an average width of 38.5 ± 12.4 nm and a length of 431.5 ± 63.1 nm in the cytoplasm. However, YSV or FFYSV displayed obvious toxicity while CB[7]-YSV or CB[7]-FFYSV exhibited negligible toxicity to HepG2 cells with low expression of SPM. Furthermore, the SPM-instructed release and subsequent in situ self-assembly of FFYSV enhanced antitumor efficacy of YSV in vivo. We envision that the host-guest interaction-instructed in situ self-assembly will be useful for effective treatment of diseases in the future.

Background: Gallstones or cholelithiasis are a major public health issue, which often remain asymptomatic, although they can sometimes cause discomfort by obstructing the digestive tract. Spermidine (SPD) and Spermine (SPE) are two polyamines (PAs) that regulate the growth of hepatocytes in the liver. The PAs play two functions in preserving cellular oxidative equilibrium by generating reactive oxygen species (ROS) and providing protection against free radical damage when serving as an enzyme substrate. Therefore, levels and metabolism of PA serve as significant markers of neoplastic alterations in the liver.Methods: Gallstone patients from multiple internal medicine hospitals were surveyed, and samples were taken and evaluated from them. Similarly, samples from healthy individuals were also taken. Under regular laboratory circumstances, the patient samples were characterized using biochemical tests, and their data was documented.Result: The levels of polyamines (PAs) and the common oxidative stress (OS) biomarker malondialdehyde (MDA) were determined. The main liver function tests and lipid profile levels showed no significant differences between the two studied groups. Whereas malondialdehyde (MDA), SPE, and SPD levels were significantly higher in patients than in the control group.Conclusion: The results of the study led to an association between polyamine levels and gallstone disease. An increase in PA levels was observed in cholelithiasis patients. It is concluded that PAs are associated with cholelithiasis and may be considered as potential predictors of this disease.Keywords:Cholelithiasis, Spermine, Spermidine, Malondialdehyde, Oxidative stress

The study investigated the biochemical and bioactive profiles of three wild inedible mushrooms— Cortinarius trivialis , Mycena pura , and Mycena rosea —focusing on polyamine (PA) content, polyphenols, proteins, antioxidants, and acetylcholinesterase (AChE) inhibition. Among the three PAs measured (putrescine (PUT), spermidine (SPD), and spermine (SPM)), C. trivialis showed the highest levels of PUT and SPD, distinguishing it metabolically. In contrast, M. pura and M. rosea had lower PA levels but were richer in proteins and phenolics. Notably, M. rosea had the highest protein content (42.46%), while M. pura exhibited the greatest total phenolic and flavonoid content, correlating with its strong antioxidant activity across multiple assays. M. rosea demonstrated selective ABTS radical scavenging and the most potent AChE inhibition (93.24 ± 7.90%), suggesting potential neuroprotective benefits. Phenolic profiling revealed species‐specific compounds: C. trivialis was rich in p ‐hydroxybenzoic and quinic acids, while Mycena species contained protocatechuic acid and trace flavonoids. Principal component analysis underscored distinct biochemical clustering: M. pura with antioxidant‐rich phenolics, M. rosea with neuroprotective SPD content, and C. trivialis with elevated PUT. This is the first report detailing PA composition and AChE inhibition in these mushrooms, highlighting their unique and complementary antioxidant and neuroprotective potential.

The physiological relevance of in vitro models is limited because conventional two-dimensional cell culture systems are unable to replicate the structural and functional complexity of native tissues. Extracellular matrix (ECM)-mimetic hydrogels have become important platforms for tissue engineering applications. This work developed hybrid hydrogels that mimic important biochemical and mechanical characteristics of cardiac tissue by combining decellularized bovine pericardium-derived (dBP) ECM, gellan gum (GG), and spermine (SPM). Although dBP offers tissue-specific biological cues, processing compromises its mechanical integrity. This limitation was overcome by adding GG, whose ionic gelation properties were optimized using DMEM and SPM. The hydrogels' mechanical, biological, physicochemical, and structural characteristics were all evaluated. Under physiologically simulated conditions, the formulations showed quick gelation and long-term stability; scanning electron microscopy revealed an interconnected, ECM-like porous microarchitecture. While uniaxial compression testing provided Young's modulus values comparable to native myocardium, rheological analysis revealed a concentration-dependent increase in storage modulus with increasing SPM content. H9C2 cardiomyoblasts were used in cytocompatibility studies to confirm that cell viability, morphology, and cytoskeletal organization were all preserved. All of these findings support the potential application of dBP-GG-SPM hydrogels in advanced in vitro cardiac models by showing that they successfully replicate important characteristics of cardiac ECM.

Development of new biologically active materials based on natural products has, over the years, attracted considerable attention due to their effectiveness in human health and disease. Polyphenolic compounds, particularly flavonoids, provide a wide range of health benefits, including antioxidant, anti-inflammatory, anticancer, and antibacterial properties. A series of novel Schiff base derivatives of flavonoids with amino-containing linkers was successfully designed and synthesized through condensation reactions. Naringin and naringenin derivatives with diamines, including ethylenediamine (EDA), 1,3-diamino-2-propanol (DA-2-PrOH), tetramethylenediamine (TMEDA), pentamethylenediamine (PMEDA), as well as polyamines spermidine (SPD) and spermine (SPM), were synthesized and well-characterized through FT-IR, UV–Visible, ESI–MS, 1H and 13C NMR spectroscopy, and elemental analysis. The so confirmed and well-characterized derivatives were subjected to photoluminescence studies, exhibiting enhanced activity, especially for naringin-based derivatives, and quenching in some others, thus verifying the significance of chemically modifying the conjugated systems of these molecules. Their biological activity was examined in the case of their antimicrobial efficacy against two Gram (+) (Staphylococcus aureus and Bacillus cereus) and two Gram (−) (Escherichia coli and Xanthomonas campestris) bacterial strains. Antibacterial screening projected selectivity of modified flavonoids against E. coli, proposing new “dense” flavonoid-(poly)amine materials as multifunctional antimicrobial agents and fluorescent probes.

The gut microbiota plays a pivotal role in modulating obesity pathogenesis, yet the molecular mechanisms underlying its protective effects remain elusive. In this study, we demonstrate that L-ornithine (L-orn), a metabolite produced by Lactobacillus, confers resistance against high-fat diet (HFD)-induced obesity in mice by modulating macrophage function through its downstream metabolites spermine (SPM) and spermidine (SPD). Mechanistically, SPM suppressed pro-inflammatory cytokine production in macrophages by inhibiting the NF-κB and Akt signaling pathways, while SPD activated Src kinase and upregulated indoleamine 2,3-dioxygenase 1 (IDO-1), thereby promoting the polarization of immunosuppressive IDO-1+ macrophages. Clinically, circulating L-orn levels were inversely correlated with body mass index (BMI) in obese individuals, underscoring its potential relevance in human obesity. Single-cell RNA sequencing (scRNA-seq) analysis further revealed dysregulated macrophage signaling in obese adipose tissue, characterized by hyperactivation of NF-κB and Akt pathways and downregulation of Src signaling in inflammatory macrophages. Collectively, our findings highlight a novel mechanism by which gut microbiota-derived L-orn mitigates obesity through metabolite-driven reprogramming of macrophages toward an anti-inflammatory phenotype, offering new therapeutic avenues for metabolic disorders.

Polyamine (PA) spermine (SPM) (i) plays an essential role in the function of neurons, while (ii) accumulating predominantly in glial cells by an unknown mechanism. In addition, the translocation of SPM synthesis and redistribution in the developing and maturating retinas remains unclear. Therefore, the expression of the SPM-synthesizing enzyme, spermine synthase (SpmS), was compared in rat retinas on postnatal days 3, 21, and 120 using immunocytochemistry, Western blot (WB), and ImageJ analyses. The anti-glutamine synthetase (GS) antibody identified glial cells, and DAPI labeled the cell nuclei. At postnatal day 3 (P3), the neonatal retina shows widespread SpmS expression throughout most neuroblast cells, but absent in the developing synaptic layers and Müller cell (MCs) processes. By day 21 (P20), SpmS becomes strongly expressed in neurons, and not in glia. On day 120 (P120), SpmS was observed in synaptic areas, with significantly less presence in neuronal soma and still none in MCs. WBs showed a decrease in SpmS expression during maturation. Therefore, glial cells do not synthesize SPM, and the accumulation of SPM in MCs found earlier suggests that glial cells take up SPM via a hypothetical high-affinity SPM transporter. In glia, SPM regulates glial connexin (Cx43) and potassium (Kir4.1) channels, being a key player in CNS diseases and aging.

Biogenic amines (BAs) are nitrogenous compounds naturally present in protein-rich foods, whose accumulation may indicate spoilage and pose health risks. This study presents the development and validation of a rapid LC–MS/MS method for the simultaneous quantification of six BAs—putrescine (PUT), cadaverine (CAD), histamine (HIS), tyramine (TYR), spermidine (SPD), and spermine (SPM)—in meat products, without requiring derivatisation. Sample preparation was optimized to enhance extraction efficiency and reproducibility, using 0.5 M HCl and a double-centrifugation protocol to avoid matrix interference. Chromatographic separation was optimized using a C18 column and acidified ammonium formate/acetonitrile mobile phases. The method showed good linearity (R2 > 0.99), trueness between −20% and +20%, and acceptable precision (RSDr and RSDR ≤ 25%). Limits of quantification were established at 10 µg/g for all analytes. The method was applied to ten commercial meat samples, where PUT, TYR, and SPD were the most frequently detected amines. Although HIS and TYR levels were below toxicological thresholds for healthy individuals, one sample showed TYR levels potentially concerning for monoamine oxidase inhibitors -treated consumers. The Biogenic Amine Index (BAI) further supported product quality assessment, identifying early spoilage in selected cases. This method offers a rapid, robust and efficient tool for routine monitoring of BAs in meat products, supporting food safety and quality control initiatives.

The transition from conchocelis to conchosporangia in Pyropia haitanensis represents a pivotal stage in its life cycle. As a commercially vital red alga, P. haitanensis plays a dominant role in global nori production. The transition governing its sporulation efficiency is pivotal for aquaculture success, yet the underlying regulatory mechanisms, especially their integration with metabolic cues such as polyamines, remain poorly understood. This study uncovered a critical role for the polyamine spermine (SPM) in promoting conchosporangial formation, mediated through the signaling activity of superoxide anions (O2·-). Treatment with SPM markedly elevated O2·- levels, an effect that was effectively inhibited by the NADPH oxidase inhibitor diphenyliodonium chloride (DPI), underscoring the role of O2·- as a key signaling molecule. Transcriptomic analysis revealed that SPM enhanced photosynthesis, carbon assimilation, and respiratory metabolism, while simultaneously activating antioxidant enzymes, such as superoxide dismutase (SOD), ascorbate peroxidase (APX), and catalase (CAT), to regulate hydrogen peroxide (H2O2) levels and maintain redox homeostasis. Furthermore, SPM upregulated genes associated with photosynthetic carbon fixation and the C2 oxidative photorespiration pathway, supplying the energy and metabolic resources necessary for this developmental transition. These findings suggested that SPM orchestrated O2·- signaling, photosynthetic activity, and antioxidant defenses to facilitate the transition from conchocelis to conchosporangia in P. haitanensis.

Palmitoylspermine: A potent antioxidant in bulk oil and emulsion.

Zn2+ protects H9C2 cardiomyocytes by alleviating MAMs-associated apoptosis and calcium signaling dysregulation.

Polyamines (PAs) are low-molecular-weight compounds that contain amino groups. PAs are present in a variety of organisms, including plants, animals and microorganisms. In plants, the main PAs are putrescine (PUT), spermidine (SPD) and spermine (SPM). They play crucial physiological roles in plant development, including flowering, fruit set, growth, ripening and metabolic processes. In addition, PAs are components of the diet and have a role in health and disease. Furthermore, PAs have been demonstrated to help overcome the negative effects of adverse environmental factors of both biotic and abiotic stresses. Thus, the main objective of this review was to examine the recent literature regarding the mentioned effects of PAs apart from the impact of preharvest PAs treatments, applied at different stages of fruit development, on fresh fruit crop yield and fruit quality properties at harvest, and in their maintenance during storage, with a special emphasis on the fruit content in bioactive compounds with antioxidant activity. Moreover, this review addressed the impact of PAs on other physiological processes affecting crop yield such as flowering and fruit set.

Spermine (SPM) is known to play a role in regulating cholesterol efflux of macrophages, which is a critical anti-atherosclerotic pathway, but the underlying mechanism remains elusive. The deficiency of caspase 2 (CASP2), a target of SPM, can induce autophagy, which promotes cholesterol efflux in atherosclerosis. Herein, we aimed to explore whether SPM could regulate CASP2-mediated autophagy in the cholesterol efflux of macrophages. Human THP-1 monocytes were induced into macrophages. After transfection and treatment with SPM or autophagy inhibitor 3-methyladenine (3-MA), the cholesterol uptake of THP-1 cell-derived macrophages and the lipid accumulation were examined using Dil-oxidized low-density lipoprotein (Dil-oxLDL) uptake assay and Oil Red O staining, respectively. The cholesterol efflux was measured by means of [3H]-cholesterol detection. Quantification of CASP2 and factors related to autophagy and apoptosis was completed using Western blotting and quantitative reverse transcription polymerase chain reaction (qRT-PCR). SPM treatment boosted cholesterol efflux and prevented lipid accumulation of THP-1 cell-derived macrophages (p < 0.001), without inducing cholesterol uptake of THP-1 cell-derived macrophages (p > 0.05). SPM upregulated the expression of autophagy-related 5 (ATG5), light chain 3 (LC3) II/LC3 I, and B-cell lymphoma-2 (Bcl-2) while downregulating Sequestosome 1 (P62) and CASP2 levels (p < 0.01). Treatment with 3-MA reversed the effects of SPM on cholesterol efflux, lipid accumulation, and autophagy-related protein expression (p < 0.01). Separately, CASP2 overexpression offset the impacts of SPM on cholesterol efflux, lipid accumulation, and expressions of proteins related to autophagy and apoptosis (p < 0.05). SPM promotes autophagy to enhance the cholesterol efflux of THP-1 cell-derived macrophages by downregulating CASP2 expression.

This study explored the molecular mechanism by which exogenous spermine attenuates diabetic cardiomyopathy (DCM)-induced myocardial fibrosis. db/db mice and primary neonatal mouse cardiac fibroblasts were used to conduct in vivo and in vitro experiments. The levels of total cholesterol (TC), triglycerides (TG), creatine kinase isoenzyme (CK-MB), troponin I (cTnI), and lactate dehydrogenase (LDH) were measured. Heart function and collagen deposition were assessed using echocardiographic analysis, Masson staining, and Sirius red staining. Cell proliferation and migration were analyzed using EdU and transwell assays. Relevant protein expression was evaluated by immunohistochemistry and western blot. After 12 weeks, the mice in the type 2 diabetes (T2D) group exhibited increased blood glucose, TG, TC, and serum myocardial marker enzyme levels. Ejection fraction (EF) and left ventricular fractional shortening left ventricular fractional shortening (FS) decreased, while LVIDs and LVIDd increased. Significant collagen fiber deposition and increased HW/TL ratio, SSAT, α-SMA, TGF-β1, and Collagen-I/III expression was observed in myocardial tissue. Conversely, ODC expression was down-regulated. In the T2D + spermine (SP) group, these trends were reversed. In vitro, high glucose conditions led to increased proliferation of cardiac fibroblasts. SSAT, α-SMA, TGF-β1, Collagen-I/III, MMP-2, MMP-9, p-Smad-2, TβRI, and TβRII were up-regulated, while ornithine decarboxylase (ODC) expression was down-regulated. Interestingly, these changes were reversed in the HG + SP group. Our findings demonstrate that SP reduces collagen synthesis and secretion by inhibiting the TGF-β1/Smads signaling pathway. These results provide new insights into potential therapeutic approaches for DCM.

A fluorescence-based assay for measuring aminopropyltransferase activity.

Polyamines, including spermidine (SPD), spermine (SPM) and putrescine (PUT), are essential for cellular physiology and various cellular processes. This study aimed to examine the associations of dietary polyamines intake and all-cause mortality and incident cardiovascular disease (CVD). This prospective cohort study included 184,732 participants without CVD at baseline from the UK Biobank who had completed at least one dietary questionnaire. Diet was assessed using Oxford WebQ, a web-based 24 h recall questionnaire, with polyamines intakes estimated from previous studies. Cox proportional models with restricted cubic splines were employed to investigate nonlinear associations. The primary endpoint was all-cause mortality or incident CVD (including CVD death, coronary heart disease and stroke). During a median follow-up period of 11.5 years, 7348 (3.9%) participants died and 12,316 (6.5%) developed incident CVD. Polyamines intake showed nonlinear associations with all-cause mortality and incident CVD (P for nonlinear < 0.01). Compared to the lowest quintile group of dietary polyamines intake (≤17.4 mg/day), the quintile 2 to 5 groups demonstrated a reduced risk of all-cause mortality, with the lowest risk in quintile 2 group (>17.4-22.3 mg/day) (HR:0.82, 95% CI: 0.76-0.88). Similar results were observed for incident CVD, with the lowest risk in the quintile 4 group (>27.1-33.5 mg/day) (HR: 0.86, 95% CI: 0.82-0.92). We found that dietary polyamines intake was associated with a lower risk of all-cause mortality or incident CVD. Furthermore, our study identified an optimal range of dietary polyamines intake.

Rice blast, caused by the fungal pathogen Magnaporthe oryzae, is a destructive disease that affects rice (Oryzae sativa L.) on a global scale. Polyamines (PAs) play diverse roles in plant growth and development and responses to biotic and abiotic stimuli. Putrescine (PUT), spermidine (SPD), and spermine (SPM) are the primary forms of polyamines (PAs). In this study, we observed that the accumulation of apoplastic PAs significantly increased in rice plants after treatment with salt or M. oryzae. The salt-treated plants exhibited enhanced resistance to rice blast disease. RNA sequencing data indicate that S-adenosylmethionine decarboxylase (SAMDC), a key enzyme involved in the synthesis of polyamines, plays a significant role in enhancing plant resistance. Overexpression of rice SAMDC (OsSAMDC) led to a significant decrease of pathogen infection in the transgenic rice plants. Additionally, OsSAMDC overexpression plants accumulated polyamines in the cytosol and apoplast, particularly SPD and SPM. Conversely, the disease resistance and accumulation of PAs were reduced in OsSAMDC-silenced plants. Exogenous application of PAs inhibited the mycelium growth, spore germination, germ tube elongation, and appressorium formation in M. oryzae. These results demonstrated that OsSAMDC-mediated polyamine biosynthesis, especially SPD and SPM, plays an essential role in rice plants to resist biotic and abiotic stresses.

Lisianthus (Eustoma grandiflorum Raf. Shinn.) is a valued plant known for its diverse flower colors and long vase life. Despite considerable research on the physiological roles of osmolytes, polyamines, and phenolic compounds, there is a lack of understanding regarding their specific accumulation patterns across various lisianthus cultivars and organs. This study aims to compare eleven lisianthus cultivars with varying flowering periods according to their accumulation of osmolytes, polyamines, phenolic content, and antioxidant capacities and measure their resistance to abiotic stress factors. High-performance liquid chromatography coupled with fluorescent detection was employed to quantify putrescine (PUT), spermidine (SPD), and spermine (SPM). In addition, proline (PRO), glycine betaine (GB), antioxidant capacities, phenolic content, and flavonoid contents were assessed spectrophotometrically. This comprehensive analysis allowed for a detailed understanding of the biochemical markers. The result indicates a significant genotype and organ-dependent variation in accumulation patterns of inspected metabolites and antioxidant activities. The petals of Rosita Green exhibited the highest levels of phenols and flavonoids, whereas the petals of Rosita Blue Picote demonstrated the highest concentrations of osmolytes. Polyamines were found to be more concentrated in the petals than in the leaves. The average values indicated high levels of polyamines in the Mariachi Carmine (PUT 186.72 nmol g−1 DW) and Mariachi Pink (SPD 227.4 nmol g−1 DW) cultivars. These findings underscore the significance of inspected compounds in stress tolerance among cultivars with different flowering periods, providing insights for optimizing cultivation strategies for lisianthus.

Tailoring a novel all-in-one host-guest solid-state electrochemiluminescence platform for selective detection of spermine using cucurbit-[6]-uril modified [Ru(bpy)3]2+ electrode

Sugarcane smut fungus Sporisorium scitamineum produces polyamines putrescine (PUT), spermidine (SPD), and spermine (SPM) to regulate sexual mating/filamentous growth critical for pathogenicity. Besides de novo biosynthesis, intracellular levels of polyamines could also be modulated by oxidation. In this study, we identified two annotated polyamine oxidation enzymes (SsPAO and SsCuAO1) in S. scitamineum. Compared to the wild type (MAT‐1), the ss1paoΔ and ss1cuao1Δ mutants were defective in sporidia growth, sexual mating/filamentation, and pathogenicity. The addition of a low concentration of cAMP (0.1 mM) could partially or fully restore filamentation of ss1paoΔ × ss2paoΔ or ss1cuao1Δ × ss2cuao1Δ. cAMP biosynthesis and hydrolysis genes were differentially expressed in the ss1paoΔ × ss2paoΔ or ss1cuao1Δ × ss2cuao1Δ cultures, further supporting that SsPAO‐ or SsCuAO1‐based polyamine homeostasis regulates S. scitamineum filamentation by affecting the cAMP/PKA signalling pathway. During early infection, PUT promotes, while SPD inhibits, the accumulation of reactive oxygen species (ROS) in sugarcane, therefore modulating redox homeostasis at the smut fungus–sugarcane interface. Autophagy induction was found to be enhanced in the ss1paoΔ mutant and reduced in the ss1cuao1Δ mutant. Exogenous addition of cAMP, PUT, SPD, or SPM at low concentration promoted autophagy activity under a non‐inductive condition (rich medium), suggesting a cross‐talk between polyamines and cAMP signalling in regulating autophagy in S. scitamineum. Overall, our work proves that SsPAO‐ and SsCuAO1‐mediated intracellular polyamines affect intracellular redox balance and thus play a role in growth, sexual mating/filamentation, and pathogenicity of S. scitamineum.