Multiple sclerosis (MS) is an immune-mediated chronic neuroinflammatory and neurodegenerative disorder. Inflammation in MS disrupts the barriers between blood and central nervous system and affects transport and diffusion of metabolites between blood and cerebrospinal fluid (CSF). In this exploratory retrospective case-control study, we used targeted metabolomics to evaluate differences in serum and CSF amino acid and neurotransmitter levels between patients with MS (n = 73) and non-neuroinflammatory controls (n = 78). The influence of patient characteristics, including sex, age, disease duration, severity and treatment status, was also analzyed. Although no significant differences in serum and CSF metabolite levels were found between MS and control patients, a stratification by sex uncovered significantly reduced metabolites in male MS patients compared to male controls in CSF but not in serum. While in male MS patients CSF histidine levels were decreased, female MS patients showed increased levels. Further, sex-specific associations of amino acids and neurotransmitters with disease duration and disability were observed. MS patients exhibited enhanced positive correlations between CSF and serum analyte levels. In serum, only a few amino acids, along with serotonin and glutathione, were associated with MS disease duration. Overall, this study suggests that targeted metabolomics of selected analytes in matched CSF and serum samples is a valuable approach for assessing alterations in CSF-serum metabolite associations in MS, as well as sex-specific imbalances between excitatory and inhibitory neurotransmitters across disease duration. Our findings further highlight the importance of considering sex as a key biological factor in MS.
The felting of wool directly on the sheep largely affects its value as a raw material for the textile industry. In this regard, the aim of this study was to investigate the amino acid and mineral composition of wool affected by this defect in sheep of the Ukrainian Carpathian Mountain breed. Experimental wool samples were divided into guard and down fibers. The amino acid composition was determined using an AAA-400 amino acid analyzer, the mineral composition was determined using an atomic absorption spectrophotometer (Thermo Scientific iCE 3500), and sulfur was determined by the nephelometric method based on the turbidity of a barium sulfate suspension stabilized with glycerin. It has been shown that the process of wool felting is accompanied by partial degradation of fibers resulting from the destruction of disulfide, ionic, and hydrogen bonds, as indicated by a significant decrease in the total amino acid content, due to reductions in aspartic (P < 0.01) and glutamic (P < 0.01) acids, arginine (P < 0.05), as well as cystine (P < 0.01) and histidine (P < 0.05) in down fibers, and lysine (P < 0.01) in guard fibers. The observed decrease in calcium and copper content in felted wool indicates a disruption of ionic interactions with the functional groups of amino acids, which play a key role in stabilizing the structural organization of wool fibers, while the decrease in sulfur content in down fibers confirms the destruction of disulfide bonds. Therefore, the results of the study indicate that wool felting is the result of biochemical processes leading to disruption of the keratin structure of the fiber. In the future, the obtained data may be used to develop comprehensive approaches aimed at preventing and eliminating this wool defect.
The bioconversion of agricultural crop straw using black soldier fly larvae (BSFL, Hermetia illucens) offers a promising strategy for recycling residual nutrients into high-value insect biomass. However, rearing BSFL on crop straw alone typically results in delayed development and poor substrate conversion efficiency. Here, we compared BSFL performance across three common agricultural residues-corn stover, rice straw, and wheat straw-and found that larvae reared on corn stover achieved significantly greater body weight and crude fat content. Ultra-performance liquid chromatography-electrospray ionization mass spectrometry (UPLC/ESI-MS) revealed higher levels of branched-chain amino acids (BCAAs) in corn stover than in the other substrates. Supplementation experiments confirmed that BCAAs significantly enhanced larval biomass and lipid accumulation. Gas chromatography (GC) analysis showed marked increases in lauric and oleic acid content in BSFL fed BCAA-supplemented rice straw. RNA interference (RNAi)-mediated knockdown of key BCAA catabolic genes including branched-chain amino acid aminotransferase (BCAT) and branched-chain α-keto acid dehydrogenase (BCKDH) impaired BCAA catabolism, resulting in reduced growth and fat storage. These findings demonstrate that enrichment of BCAAs in corn stover are efficiently assimilated by BSFL under low-nitrogen conditions to promote lipid accumulation, which offering a practical strategy to enhance bioconversion efficiency in waste valorization and insect-based protein production.
Previous studies have shown that alterations in the gut microbiota and its derived metabolites, branched-chain amino acids (BCAAs), are correlated with T-cell-associated immune imbalance and Parkinson's disease (PD). However, the associations among BCAAs, gastrointestinal dysfunction and T-cell-related gut inflammation remain unclear. This study showed that the constipation symptoms in the PD mice persisted after chronic MPTP treatment. An imbalance in the CD4+ T-cell subtypes was observed in the colonic lamina propria (cLP), mesenteric lymph nodes (mLNs), and spleen. Metagenomic and metabolomic analyses showed that microbial dysbiosis promoted BCAA degradation rather than biosynthesis, and reduced BCAA levels were confirmed in the serum. BCAA supplementation alleviated constipation symptoms and increased Th1 and Th17 cell infiltration in the cLP, mLNs and spleen were significantly attenuated after BCAA treatment. This study highlights the therapeutic value of BCAAs in mitigating gut immune inflammation-associated constipation symptoms in PD.
The PhI(OAc)2-oxidation of the triterpene lupeol by manganese porphyrin was achieved, leading to 94% of lupeol conversion. Conditions aligned with principles of green chemistry, including the use of ethyl acetate as a solvent and iodobenzene diacetate as an oxidant, were studied. This approach led to the production of eight products from lupeol, notably achieving transformations at the C20 olefin moiety; six lupeol's products were isolated whereas the other two had their structures proposed supported on basic chemical tests (e.g., Fehling's test) and well‑established reactivity patterns in organic chemistry. These modifications were performed without the typical preceding protection of the C3 hydroxyl of lupeol, simplifying the synthetic route. Besides, the isopropenyl group of lupeol was converted to carboxylic acids through one-pot oxidation. This study reinforces the promising use of manganese porphyrins as catalysts for the oxidative transformation of other natural products of biological interest.
Understanding the subcellular localization of RNA and proteins is critical to dissecting gene regulation in eukaryotic organisms. However, this task is elusive as existing fractionation methods often rely on protoplast isolation or commercial kits, that are labor-intensive, costly, and can introduce stress-induced transcriptomic and proteomic changes. Here, we present a simple, rapid, and cost-effective protocol for the fractionation of nuclear and cytoplasmic components directly from diverse plant tissues, that does not require protoplastization. This Subcellular-fractionation protocol in 3 steps (a.k.a. "bueno, bonito y barato" -spanish for "good, nice and cheap"-), referred to as "SuB3", yields nuclear- and cytoplasmic- enriched subcellular fractions suitable for downstream applications such as RT-PCR, RNA/cDNA sequencing, and Western blotting. The procedure is based on sequential detergent-assisted extraction and centrifugation and enables the simultaneous isolation of RNA and protein from the same biological material. Due to its simplicity, speed, and broad compatibility, this protocol is a valuable tool for plant molecular biology laboratories investigating subcellular dynamics of gene expression.
The activation by Lewis acids (LAs) and visible-light excitation are two appealing strategies for generating highly oxidizing metal oxo species for catalytic oxidation reactions. Herein, we report the first systematic study on the activation of both the ground and excited states of a luminescent osmium(VI) dioxo dicyano complex (OsO2). Strong interactions of OsO2 with a variety of LAs were found via binding to the cyano ligands: LA-NC-Os-CN-LA, which allow the isolation and structural determination of the first examples of M=O/LA adducts. OsO2/2LA interactions also cause a large increase in the reduction potentials/oxidizing power of the adducts in both ground and excited states. Notably, the reduction potential (Epc) of OsO2 is shifted from -0.04 V (vs. NHE) to 1.21 V in the presence of Sc(OTf)3, which enables it to oxidize a variety of organic substrates. More significantly, the Epc for the excited state of OsO2 (OsO2*) is shifted from 2.21 to 3.50 V upon binding to Sc(OTf)3, which to our knowledge is the strongest metal oxo oxidant ever generated in solution. OsO2*/2Sc(OTf)3 readily catalyzes the oxidation of benzene and its derivatives by H2O2 at ambient conditions, with a TON up to 8660 and gram-scale production of phenol from benzene.
Diaryl ureas and thioureas have long been known to uncouple oxidative phosphorylation in isolated mitochondria and cells. However, the mechanism of this action remains poorly understood. The prevailing current view is that substituted diaryl ureas can increase the proton conductance of lipid membranes by forming complexes with fatty acids. For 1,3-bis[4-(trifluoromethyl)phenyl]urea (TFMP-urea), we showed that this substituted diphenylurea, in the absence of fatty acids at neutral pH, accelerated proton transport and H+/Cl- symport on planar bilayer lipid membranes (BLMs) and liposomes loaded with the fluorescent pH-sensitive probe 8-hydroxypyrene-1,3,6-trisulfonic acid. The protonophoric action of TFMP-urea proceeded via translocation of neutral protonated form and anionic deprotonated form through the membrane. The presence of palmitic acid in the lipid mixture led to a several-fold increase in the BLM current mediated by TFMP-urea and an improvement in its proton selectivity. We also showed that bovine serum albumin reduced the BLM current mediated by TFMP-urea due to its ability to bind this compound.
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Palladium-catalyzed β and γ-C-H arylation of free carboxylic acids with both aryl boron reagents and aryl iodides has been extensively developed in recent years. Replacing these aryl coupling partners with simple arenes remains a significant challenge. By developing pyridone-morpholine ligands, we disclosed the β-methylene C-H (hetero)arylation of acyclic aliphatic acids and the γ-(hetero)arylation of cycloalkane carboxylic acids using benzene, furan, thiophene, and C-2 substituted pyridine as coupling partners. Preliminary mechanistic studies suggest that the reaction proceeds via ligand-promoted dehydrogenation of aliphatic carboxylic acids, C(sp2)-H activation of (hetero)arenes, and subsequent hydroarylation. Building on the mechanistic insights, we developed a dual-ligand catalysis system with one ligand promoting dehydrogenation and the other enhancing subsequent steps to enable coupling of C(sp3)-H bonds with indoles and pyrroles as reaction partners.
Metabolic dysfunction-associated steatotic liver disease (MASLD) and its inflammatory-fibrotic phenotype (MASH) exhibit pronounced immunometabolic coupling. This review synthesizes evidence along the gut-liver axis, from epithelial tight-junction and gut vascular barrier (GVB) failure to TLR4-MyD88/TRIF-NF-κB amplification and NLRP3 inflammasome activation and outlines the logic of the gut-derived exposure spectrum-lipopolysaccharide (LPS), endogenous ethanol, bile acids (BAs), short-chain fatty acids (SCFAs), and trimethylamine N-oxide (TMAO). We position BA-FXR/TGR5, SCFAs-GPR41/43, and AMPK/Nrf2 as upstream/downstream modulators that reset inflammatory thresholds and confer stage-dependent druggability. Based on node-to-pathway mapping, we summarize mechanisms and translational signals for berberine (BBR), Qushihuayu (QSHY), Da-Chai-Hu Decoction (DCHD), and polysaccharides (e.g., Astragalus, Ganoderma), emphasizing pharmacokinetic and site-of-exposure constraints that support "gut-first" actions. We propose a minimal companion biomarker set-LBP/sCD14, BA profiles with FGF19-C4 dynamics, and IL-1β/GSDMD-N-paired with hierarchical imaging gates (≥30% relative MRI-PDFF decline; MRE/ELF) to underpin response typing and go/no-go decisions. Finally, we highlight critical gaps (direct human GVB readouts; longitudinal multi-omics bridged to clinical outcomes) and outline a biomarker-driven multi-arm multi-stage (MAMS) pathway for adaptive, stratified development of multi-target traditional medicine interventions in MASLD/MASH.
The functional efficacy of dietary Jamun leaf meal (JLM) on growth performance, physiological status, immune competence, and disease resistance was evaluated in Pangasianodon hypophthalmus. Comprehensive phytochemical profiling revealed the presence of flavonoids, phenolic acids, terpenoids, vitamins, amino acids, and minerals in the JLM extract. Five isonitrogenous and isocalorific experimental diets containing 0, 0.5, 1.0, 1.5, 2% JLM were prepared and fed to the respective treatment groups for 60 days. The group fed with 1% JLM diet exhibited improved weight gain (16.46 ± 0.12 g), specific growth rate (1.41 ± 0.02% day⁻1), protein efficiency ratio (2.47 ± 0.06), and feed conversion ratio (1.34 ± 0.03) (P < 0.05). Pre-challenge, the haematological, biochemical, immune, and antioxidant parameters improved significantly in 1% JLM-fed group (P < 0.05). Post-challenge, the stress biomarkers, namely glucose, cholesterol, and triglycerides, and hepatic enzymes were significantly elevated (P < 0.05) in the control group compared to the JLM-fed groups. Furthermore, the cumulative survival was significantly higher in the 1% JLM-fed group (87.67 ± 5.7%) than in the control group (P < 0.05). In conclusion, dietary administration of JLM at 1% inclusion level enhances growth and health performance in P. hypophthalmus and is a potential feed supplement.
Soybeans serve as excellent sources of vegetable oil, protein, and other valuable nutrients for human consumption, materials for diverse industries, including the cosmetics and medical industries, and feedstocks for animals. Nevertheless, some people do not favor soy oil or other various food products derived from soybeans, due to inadequate levels of oleic acid in the oil and the presence of undesirable grassy and beany flavors associated with oxidation products of polyunsaturated fatty acids in the seeds. In this study, we developed soybean cultivars with very high levels of oleic acid in the seeds, and without grassy and beany flavors. We achieved this by using CRISPR-Cas-SF01 to edit genes in the elite cultivar Xudou 18 (XD18), targeting two microsomal Δ-12 fatty acid desaturase 2 (GmFAD2-1A and GmFAD2-1B) and three lipoxygenase (GmLOX1, GmLOX2, and GmLOX3) genes. Our findings showed that fad2-1a/b and fad2-1a/b/lox1/2/3 plants performed similarly to XD18 plants in the field, indicating no obvious growth penalties. Overall, this research has demonstrated that the development of soybean germplasms with high levels of oleic acid and without undesirable beany flavors through gene-editing of multiple relevant genes is effective, and this endeavor can contribute to the health of a broader global consumer population.
Hepatocellular carcinoma (HCC) remains a major global cause of cancer-related deaths. HCC development, immune evasion, and treatment resistance are significantly influenced by the aberrant activation of the NF-κB and JAK/STAT signaling pathways. The review provides a thorough and critical analysis of recent developments in nanocarrier-mediated targeting of NF-κB and JAK/STAT pathways in HCC. It demonstrates the molecular interactions between various pathways and their implications for inflammation, angiogenesis, hepatocarcinogenesis, and resistance to both immunotherapy and chemotherapy. A variety of nanoplatforms, such as polymeric nanoparticles, lipid-based systems, inorganic nanomaterials, and biomimetic carriers, are designed to enhance the delivery of small-molecule inhibitors, nucleic acids, and combination therapies, improving pharmacokinetic and pharmacodynamic profiles. The review highlights ligand-functionalized and stimulus-responsive nanocarriers designed for controlled drug release and targeted therapy in the liver environment. Co-modulation of NF-κB and JAK/STAT signaling via nanotechnology enhances antitumor efficacy and decreases systemic toxicity, as supported by preclinical and recent translational data. Lastly, important issues such as scalability, biosafety, and regulatory concerns are discussed. Future directions for integrating precision cancer techniques with nanomedicine are proposed. This analysis emphasizes the therapeutic potential of targeting the NF-κB and JAK/STAT pathways with nanotechnology to enhance outcomes in HCC.
This study presents an integrated waste-to-energy strategy for the sustainable conversion of the biodegradable organic fraction of municipal solid waste (BOFMSW) into biohydrogen (Bio.H2) and biomethane (Bio.CH4) through a two-stage continuous stirred dark fermentation (DF) process. The first-stage bioreactor was inoculated with Clostridium Thermocellum selectively enriched in a 2-bromoethanesulfonic acid (BESA) medium, and the influence of bimetallic ion catalysts NiCl2 + FeCl2 and NiCl2 + FeSO4 was evaluated at various concentrations (25, 50, 75, and 100 mg/L). The catalyst combination NiCl2 + FeCl2 at 75 mg/L produced the maximum Bio.H2 yield of 3162 L, representing a 69% enhancement compared with the catalyst-free substrate. At this optimal catalytic concentration, the percentage of H2 in the gas composition was 69.26%. The second-stage bioreactor utilized the effluent from the first stage for Bio.CH4 generation, achieving the highest cumulative yield of 729 L at 50 mg/L NiCl2 + FeCl2, which was 59% higher than that of the catalyst-free substrate. The two-stage process achieved an overall COD removal efficiency of 93.18%, demonstrating the system's effective capacity for energy recovery. Fourier Transform Infrared (FTIR) and Field Emission Scanning Electron Microscopy (FESEM) analyses confirmed the biochemical and morphological degradation of complex organics into volatile fatty acids, illustrating efficient substrate conversion and microbial proliferation. The final digested slurry, rich in nitrogen, phosphorus, and potassium, was found suitable for use as a bio-fertilizer, supporting nutrient recycling and soil enrichment. This integrated process not only improved energy recovery efficiency but also achieved near-zero waste discharge, combining waste-to-energy and waste-to-resource approaches. The developed system demonstrates strong potential for pilot-scale implementation of Bio.H2, and Bio.CH4 for co-production from municipal solid waste (MSW), offering a circular bioeconomy pathway toward low-carbon, sustainable urban waste management.
The principle "hard acids prefer hard bases" from the Hard and Soft Acid-Base (HSAB) theory, has gained extensive validation. However, the interaction mechanisms between borderline acid metals and hard base groups remain unclear, limiting the rational design of highly selective adsorption. This study systematically investigates the synthesis of hard base-functionalized UiO-66 materials (UiO-66-X, X = -NH2, -OH, and -COOH) and their efficacy in adsorbing borderline acid metal (Cu(II), Co(II), Ni(II), Pb(II)). Comprehensive characterization confirms the preservation of the parent framework and the successful introduction of functional groups. Batch adsorption experiments reveal that the solution pH and the pairing between functional groups and metal ions are critical factors affecting adsorption capacity and selectivity. The -OH group exhibits strong affinity for Cu(II), Co(II), and Pb(II), -COOH for Pb(II) and Cu(II), and -NH2 is exceptionally selective for Ni(II). The mechanism, elucidated through XPS and DFT calculations (ESP, DOS, and adsorption energy), verifies coordination between metal ions and the N/O atoms of hard base groups. Additionally, the introduction of -COOH groups through para-functionalization improves the adsorption rate and selectivity per functional group by modulating the electronic structure. This study provides fundamental insights into the structure-activity relationship, aiding in the design of highly selective MOF-based adsorbents.
Environmental exposure to complex chemical mixtures threatens metabolic health by disrupting the liver-gut microbiota axis. This study assesses a multi-pollutant cocktail (PC) comprising As, Cd, Hg, diclofenac and flumequine, on bile acid (BA) homeostasis in mice and evaluates the protective potential of dietary selenium. PC exposure induced mortality and body-weight loss despite sublethal individual doses, suggesting synergistic toxicity. Selenium supplementation, however, attenuated weight loss and partially reduced mortality. Hepatic profiling showed that antibiotic-induced microbiota depletion sharply reduced taurocholic acid, whereas PC exposure increased total hepatic BAs. However, selenium normalized total BAs and partially restored secondary species. Cholic acid remained stable, while PC exposure nearly depleted glycocholic and deoxycholic acids and increased taurodeoxycholic acid, a shift associated with colorectal and lung pathologies. These findings suggest xenobiotic-mediated disruption of BA conjugation and dysregulation of nuclear receptors, potentially predisposing to hepatic steatosis. Collectively, these findings support selenium as a nutritional strategy to mitigate antibiotic-induced dysbiosis and PC-induced hepatotoxicity, preserving metabolic integrity under chemical stress.
Antimicrobial proteins/peptides (AMPs) are promising bioactive molecules with potent and broad-spectrum activity, representing a key alternative to conventional antibiotics. Among these host defense molecules, ribosomal proteins represent a largely unexplored reservoir with potential antimicrobial capacity, as recent studies suggest that certain members possess moonlighting antimicrobial activity. Thus, studies on the antimicrobial activity of ribosomal protein subunits broaden our knowledge of these antimicrobial moonlighting proteins and contribute to better strategies to combat antimicrobial resistance. In this study, we report the antimicrobial capacity of a newly identified 40S ribosomal protein S27a from the starfish Patiria pectinifera (PpRPS27a). We retrieved a 40S ribosomal protein S27a homolog from a transcriptome-derived EST database of P. pectinifera. Subsequent cDNA cloning yielded an 804-bp cDNA comprising a 52-bp 5'-UTR, a 462-bp ORF, and a 290-bp 3'-UTR, revealing that PpRPS27a is expressed together with ubiquitin as a fusion protein. The mature PpRPS27a consists of 77 amino acids with a molecular mass of 9,019.74 Da. Quantitative mRNA expression analysis showed that PpRPS27a is highly expressed in tissues associated with immune function or external exposure, including the cardiac stomach, oral haemal ring, and coelomic epithelium. Its expression was found to be upregulated upon immune challenge, suggesting a potential involvement in host defense mechanisms. The recombinant PpRPS27a (rPpRPS27a) was heterologously expressed in Escherichia coli BL21 (DE3) and purified for functional characterization. rPpRPS27a exhibited broad-spectrum antimicrobial activity against both Gram-positive and Gram-negative bacteria and a fungus. Notably, rPpRPS27a showed strong activity against fish pathogens such as Aeromonas hydrophila and Vibrio anguillarum, which are major causative agents of diseases in aquaculture. In addition, the antimicrobial activity was enhanced when rPpRPS27a was co-administered with recombinant ubiquitin (rPpUB), its native fusion partner in P. pectinifera. rPpRPS27a increases outer membrane permeability and exhibits DNA-binding activity in vitro, indicating a multifaceted antibacterial mechanism. These results indicate that PpRPS27a is a previously uncharacterized antimicrobial protein with broad-spectrum activity and a potential role in host immune defense. The discovery of PpRPS27a as an antimicrobial effector in innate immunity expands the known roles of invertebrate ribosomal proteins. Moreover, its potent activity against fish pathogens also suggests potential as a molecular scaffold for developing novel antimicrobial agents. To our knowledge, this is the first report of the antimicrobial property of the 40S ribosomal protein S27a from starfish, P. pectinifera.
This study evaluated the impact of incorporating Pleurotus ostreatus spent mushroom substrate (SMS) into corn silage-based diets on rumen fermentation, fiber digestibility, and biogas emissions using the Rumen Simulation Technique (RUSITEC). Given the need to reduce feed costs and mitigate environmentally harmful emissions from rumen fermentation, SMS was evaluated as a partial replacement for corn silage at inclusion levels of 10% (T1), 20% (T2), and 40% (T3). These three treatments were compared to a control diet consisting of 100% corn silage, to assess rumen fermentation characteristics, nutrient digestibility and biogas emissions, thereby determining the feasibility of SMS as a functional feed component in sustainable ruminant production systems. Significant improvements (P < 0.001) were observed in dry matter digestibility, which increased from 41.1% in the control to 46.8% and 48.1% in the T1 and T2 treatments, respectively. Likewise, neutral detergent fiber digestibility rose from 56.7% (control) to 62.3% (T1) and 65.1% (T2). SMS inclusion significantly decreased methane (CH4) emissions (P < 0.001), with the 10% SMS treatment reducing CH4 from 65.6 to 14.4 mg/g DM, a reduction of about 78%. Ammonia levels also declined significantly (P < 0.001) from 1025 mmol/g DM in the control to 420 mmol/g DM in the T1 group. Hydrogen sulfide emissions showed a similar pattern (P < 0.001), dropping from 7828 mmol/g DM (control) to 1817 mmol/g DM (20% SMS). Although total volatile fatty acids were not significantly affected, acetate levels increased (P = 0.046) to 74.9% (T2), and valerate was significantly higher (P < 0.001) in the T1 group (2.58%). These results indicate that replacing 10-20% of corn silage with P. ostreatus SMS can significantly enhance nutrient digestibility and reduce environmental emissions, without affecting fermentation characteristics. SMS is an economical, eco-friendly, and promising feed additive for sustainable ruminant farming.
ADP-ribosylation is an essential post-translational modification that contributes to key cellular processes, such as DNA damage repair, cell-cycle progression, chromatin remodeling, mitochondrial function, and immune responses in mammalian cells. This modification derives from NAD+ and is regulated by dedicated writer, eraser, and reader proteins that govern its installation, removal, and recognition. Traditionally viewed as a protein-centered modification, ADP-ribosylation has recently been extended to nucleic acids, with ADP-ribosylated DNA and RNA now identified in both mammalian and bacterial systems. These discoveries reveal previously underappreciated layers of nucleic acid-based regulation and suggest that NAD+-dependent chemistry integrates genome maintenance, RNA metabolism, and cellular stress responses. In this review, we first outline the major mammalian ADP-ribosylation machineries, including the families of writer, eraser, and reader proteins, and discuss how their activities are coordinated. We then examine emerging roles of ADP-ribosylation in mitochondria, with a focus on mitochondrial DNA repair and metabolic control. Finally, we highlight recent advances in understanding NAD+-dependent modifications of DNA and RNA in mammalian and bacterial cells, including terminal and nucleobase-linked ADP-ribosylation and NAD capping, and discuss outstanding questions regarding their physiological functions and interplay with protein post-translational modification and other nucleic acid modifications.