OBJECTIVE: To investigate the protective effects of stir-fried Semen Armeniacae Amarum (SAA) against aristolochic acid I (AAI)-induced nephrotoxicity and DNA adducts and elucidate the underlying mechanism involved for ensuring the safe use of Asari Radix et Rhizoma. METHODS: In vitro, HEK293T cells overexpressing Flag-tagged multidrug resistance-associated protein 3 (MRP3) were constructed by Lentiviral transduction, and inhibitory effect of top 10 common pairs of medicinal herbs with Asari Radix et Rhizoma in clinic on MRP3 activity was verified using a self-constructed fluorescence screening system. The mRNA, protein expressions, and enzyme activity levels of NAD(P)H quinone dehydrogenase 1 (NQO1) and cytochrome P450 1A2 (CYP1A2) were measured in differentiated HepaRG cells. Hepatocyte toxicity after inhibition of AAI metabolite transport was detected using cell counting kit-8 assay. In vivo, C57BL/6 mice were randomly divided into 5 groups according to a random number table, including: control (1% sodium bicarbonate), AAI (10 mg/kg), stir-fried SAA (1.75 g/kg) and AAI + stir-fried SAA (1.75 and 8.75 g/kg) groups, 6 mice in each group. After 7 days of continuous gavage administration, liver and kidney damages were assessed, and the protein expressions and enzyme activity of liver metabolic enzymes NQO1 and CYP1A2 were determined simultaneously. RESULTS: In vivo, combination of 1.75 g/kg SAA and 10 mg/kg AAI suppressed AAI-induced nephrotoxicity and reduced dA-ALI formation by 26.7%, and these detoxification effects in a dose-dependent manner (P<0.01). Mechanistically, SAA inhibited MRP3 transport in vitro, downregulated NQO1 expression in vivo, increased CYP1A2 expression and enzymatic activity in vitro and in vivo, respectively (P<0.05 or P<0.01). Notably, SAA also reduced AAI-induced hepatotoxicity throughout the detoxification process, as indicated by a 41.3% reduction in the number of liver adducts (P<0.01). CONCLUSIONS Stir-fried SAA is a novel drug candidate for the suppression of AAI-induced liver and kidney damages. The protective mechanism may be closely related to the regulation of transporters and metabolic enzymes.
Aristolochic Acids/toxicity* ; Animals ; Humans ; NAD(P)H Dehydrogenase (Quinone)/genetics* ; HEK293 Cells ; Kidney/pathology* ; Cytochrome P-450 CYP1A2/genetics* ; Mice, Inbred C57BL ; DNA Adducts/drug effects* ; Male ; Kidney Diseases/drug therapy* ; Drugs, Chinese Herbal/therapeutic use* ; Mice ; Prunus armeniaca ; Plant Extracts

Cardiovascular diseases (CVDs) are the leading cause of death worldwide. Nicotinamide adenine dinucleotide (NAD⁺) is a central and pleiotropic metabolite involved in multiple cellular energy metabolism, such as cell signaling, DNA repair, protein modifications, and so on. Evidence suggests that NAD⁺ levels decline with age, obesity, and hypertension, which are all significant CVD risk factors. In addition, the therapeutic elevation of NAD⁺ levels reduces chronic low-grade inflammation, reactivates autophagy and mitochondrial biogenesis, and enhances antioxidation and metabolism in vascular cells of humans with vascular disorders. In preclinical animal models, NAD⁺ boosting also extends the health span, prevents metabolic syndrome, and decreases blood pressure. Moreover, NAD⁺ storage by genetic, pharmacological, or natural dietary NAD⁺-increasing strategies has recently been shown to be effective in improving the pathophysiology of cardiac and vascular health in different animal models and humans. Here, we discuss NAD⁺-related mechanisms pivotal for vascular health and summarize recent research on NAD⁺ and its association with vascular health and disease, including hypertension, atherosclerosis, and coronary artery disease. This review also assesses various NAD⁺ precursors for their clinical efficacy and the efficiency of NAD⁺ elevation in the prevention or treatment of major CVDs, potentially guiding new therapeutic strategies.
Humans ; Cardiovascular Diseases/physiopathology* ; NAD/metabolism* ; Animals ; Hypertension/metabolism*

OBJECTIVE: To explore the mechanism by which ω-3 polyunsaturated fatty acids (hereinafter referred to as "ω-3") exert antioxidant stress protection and promote osteogenic differentiation in MC3T3-E1 cells, and to reveal the relationship between ω-3 and the key antioxidant stress pathway involving nuclear factor E2-related factor 2 (Nrf2) and NAD (P) H quinone oxidoreductase 1 (NQO1) in MC3T3-E1 cells. METHODS: The optimal concentration of H ₂O ₂ (used to establish the oxidative stress model of MC3T3-E1 cells in vitro) and the optimal intervention concentrations of ω-3 were screened by cell counting kit 8. MC3T3-E1 cells were divided into blank control group, oxidative stress group (H ₂O ₂), low-dose ω-3 group (H ₂O ₂+low-dose ω-3), and high-dose ω-3 group (H ₂O ₂+high-dose ω-3). After osteoblastic differentiation for 7 or 14 days, the intracellular reactive oxygen species (ROS) level was measured by fluorescence staining and flow cytometry, and the mitochondrial morphological changes were observed by biological transmission electron microscope; the expression levels of Nrf2, NQO1, heme oxygenase 1 (HO-1), Mitofusin 1 (Mfn1), and Mfn2 were detected by Western blot to evaluate the cells' antioxidant stress capacity; the expression levels of Runt-related transcription factor 2 (RUNX2) and osteocalcin (OCN) were detected by immunofluorescence staining and Western blot; osteogenic potential of MC3T3-E1 cells was evaluated by alkaline phosphatase (ALP) staining and alizarin red staining. RESULTS: Compared with the oxidative stress group, the content of ROS in the low and high dose ω-3 groups significantly decreased, and the protein expressions of Nrf2, NQO1, and HO-1 significantly increased ( P<0.05). At the same time, the mitochondrial morphology of MC3T3-E1 cells improved, and the expressions of mitochondrial morphology-related proteins Mfn1 and Mfn2 significantly increased ( P<0.05). ALP staining and alizarin red staining showed that the low-dose and high-dose ω-3 groups showed stronger osteogenic ability, and the expressions of osteogenesis-related proteins RUNX2 and OCN significantly increased ( P<0.05). And the above results showed a dose-dependence in the two ω-3 treatment groups ( P<0.05). CONCLUSION ω-3 can enhance the antioxidant capacity of MC3T3-E1 cells under oxidative stress conditions and upregulate their osteogenic activity, possibly through the Nrf2/NQO1 signaling pathway.
Oxidative Stress/drug effects* ; NF-E2-Related Factor 2/metabolism* ; NAD(P)H Dehydrogenase (Quinone)/metabolism* ; Animals ; Mice ; Osteogenesis/drug effects* ; Cell Differentiation/drug effects* ; Fatty Acids, Omega-3/pharmacology* ; Signal Transduction/drug effects* ; Osteoblasts/drug effects* ; Reactive Oxygen Species/metabolism* ; Cell Line ; Hydrogen Peroxide/pharmacology* ; Core Binding Factor Alpha 1 Subunit/metabolism* ; Antioxidants/pharmacology* ; Heme Oxygenase-1/metabolism*

Ribosomally synthesized and post-translationally modified peptides (RiPPs) constitute a vast and diverse family of bioactive peptides. These peptides, synthesized by ribosomes and subsequently modified by various tailoring enzymes, possess a wide chemical space. Among these modifications, radical S-adenosylmethionine (rSAM) enzymes employ unique radical chemistry to introduce a variety of novel peptide structures, which are crucial for their activity. This review examines the major types of modifications in RiPPs catalyzed by rSAM enzymes, incorporating recent advancements in protein structure analysis techniques and computational methods. Additionally, it elucidates the diverse catalytic mechanisms and substrate selectivity of these enzymes through an analysis of the latest crystal structures.
Protein Processing, Post-Translational ; S-Adenosylmethionine/chemistry* ; Ribosomes/metabolism* ; Peptides/metabolism* ; Biological Products/metabolism* ; Humans

β-Nicotinamide mononucleotide (NMN), as the precursor of nicotinamide adenine dinucleotide (NAD), plays an important role in enhancing NAD levels. Intake of NMN can alter the composition and vitality of gut microbiota, restore mitochondrial function, inhibit inflammatory pathways, improve metabolism, counteract oxidative stress, and alleviate inflammation. NMN significantly improves recovery from aging-related diseases, such as diminished heart function, reduced fertility, memory decline, and diabetes. NMN demonstrates both efficacy and safety in anti-aging. The use of NMN in China has gradually gained acceptance, highlighting the importance of exploring the mechanism of NMN in anti-aging effects and improving the biosynthesis of NMN. In addition, NMN in combination with stem cells hold promise in the treatment of aging-related degenerative diseases and promote overall human and animal health.
Humans ; Nicotinamide Mononucleotide/pharmacology* ; Aging/physiology* ; Animals ; Oxidative Stress/drug effects* ; Gastrointestinal Microbiome ; NAD/metabolism*

NAD(P)H: quinone oxidoreductase 1 (NQO1) is a flavin protease highly expressed in various cancer cells. NQO1 catalyzes a futile redox cycle in substrates, leading to substantial reactive oxygen species (ROS) production. This ROS generation results in extensive DNA damage and elevated poly (ADP-ribose) polymerase 1 (PARP1)-mediated consumption of nicotinamide adenine dinucleotide (NAD⁺), ultimately causing cell death. Nicotinamide phosphoribosyltransferase (NAMPT), the rate-limiting enzyme in the NAD⁺ salvage synthesis pathway, emerges as a critical target in cancer therapy. The concurrent inhibition of NQO1 and NAMPT triggers hyperactivation of PARP1 and intensive NAD⁺ depletion. In this study, we designed, synthesized, and assessed a novel series of proqodine A derivatives targeting both NQO1 and NAMPT. Among these, compound T8 demonstrated potent antitumor properties. Specifically, T8 selectively inhibited the proliferation of MCF-7 cells and induced apoptosis through mechanisms dependent on both NQO1 and NAMPT. This discovery offers a promising new molecular entity for advancing anticancer research.
Humans ; NAD/metabolism* ; Cell Line, Tumor ; Reactive Oxygen Species/metabolism* ; Nicotinamide Phosphoribosyltransferase/metabolism* ; Cytokines/metabolism* ; Quinones ; Oxidoreductases

Nicotinamide adenine dinucleotide（NADH） in its reduced form of is a key coenzyme in redox reactions, essential for maintaining energy homeostasis.NADH and its oxidized counterpart, NAD+, form a redox couple that regulates various biological processes, including calcium homeostasis, synaptic plasticity, anti-apoptosis, and gene expression. The reduction of NAD+/NADH levels is closely linked to mitochondrial dysfunction, which plays a pivotal role in the cascade of various neurodegenerative disorders, including Parkinson's disease and Alzheimer's disease.Auditory neuropathy（AN） is recognized as a clinical biomarker in neurodegenerative disorders. Furthermore, mitochondrial dysfunction has been identified in patients with mutations in genes like OPA1and AIFM1. However, effective treatments for these conditions are still lacking. Increasing evidence suggests that administratering NAD+ or its precursors endogenously may potentially prevent and slow disease progression by enhancing DNA repair and improving mitochondrial function. Therefore, this review concentrates on the metabolic pathways of NAD+/NADH production and their biological functions, and delves into the therapeutic potential and mechanisms of NADH in treating AN.
Humans ; NAD/metabolism* ; Neurodegenerative Diseases/metabolism* ; Mitochondria ; Oxidation-Reduction ; Mitochondrial Diseases

This study aims to reveal the endogenous metabolic characteristics of acteoside in the young rat model of purinomycin aminonucleoside nephropathy(PAN) by non-targeted urine metabolomics and decipher the potential mechanism of action. Biochemical indicators in the urine of rats from each group were determined by an automatic biochemical analyzer. The potential biomarkers and related core metabolic pathways were identified by ultra-high performance liquid chromatography coupled with linear ion trap-Orbitrap mass spectrometry(UHPLC-LTQ-Orbitrap MS) combined with principal component analysis(PCA) and orthogonal partial least squares-discriminant analysis(OPLS-DA). MetaboAnalyst 5.0 was used to establish the receiver operating characteristic(ROC) curve for evaluating the clinical diagnostic performance of core metabolites. The results showed that acteoside significantly decreased urinary protein-to-creatinine ratio in PAN young rats. A total of 17 differential metabolites were screened out by non-targeted urine metabolomics in PAN young rats and they were involved in phenylalanine metabolism and phenylalanine, tyrosine and tryptophan biosynthesis. Thirtten differential metabolites were screened by acteoside intervention in PAN young rats, and they were involved in phenylalanine metabolism and arginine and proline metabolism. Among them, leucylproline and acetophenone were the differential metabolites that were significantly recovered after acteoside treatment. These pathways suggest that acteoside treats PAN in young rats by regulating amino acid metabolism. The area under the curve of two core biomarkers, leucylproline and acetophenone, were both greater than 0.9. In summary, acteoside may restore amino acid metabolism by regulating endogenous differential metabolites in PAN young rats, which will help to clarify the mechanism of acteoside in treating chronic glomerulonephritis in children. The characteristic biomarkers screened out have a high diagnostic value for evaluating the treatment of chronic glomerulonephritis in children with acteoside.
Humans ; Child ; Rats ; Animals ; Puromycin Aminonucleoside ; Metabolomics/methods* ; Biomarkers/urine* ; Chromatography, High Pressure Liquid/methods* ; Acetophenones ; Glomerulonephritis ; Phenylalanine ; Amino Acids

Succinic acid is an important C4 platform chemical that is widely used in food, chemical, medicine sectors. The bottleneck of fermentative production of succinic acid by engineered Escherichia coli is the imbalance of intracellular cofactors, which often leads to accumulation of by-products, lower yield and low productivity. Stoichiometric analysis indicated that an efficient production of succinic acid by E. coli FMME-N-26 under micro-aeration conditions might be achieved when the TCA cycle provides enough ATP and NADH for the r-TCA pathway. In order to promote succinic acid production, a serial of metabolic engineering strategies include reducing ATP consumption, strengthening ATP synthesis, blocking NADH competitive pathway and constructing NADH complementary pathway were developed. As result, an engineered E. coli FW-17 capable of producing 139.52 g/L succinic acid and 1.40 g/L acetic acid in 5 L fermenter, which were 17.81% higher and 67.59% lower than that of the control strain, was developed. Further scale-up experiments were carried out in a 1 000 L fermenter, and the titer of succinic acid and acetic acid were 140.2 g/L and 1.38 g/L, respectively.
Escherichia coli/genetics* ; NAD ; Succinic Acid ; Acetic Acid ; Adenosine Triphosphate

Human induced pluripotent stem cells (hiPSCs) are promising in regenerative medicine. However, the pluripotent stem cells (PSCs) may form clumps of cancerous tissue, which is a major safety concern in PSCs therapies. Rapamycin is a safe and widely used immunosuppressive pharmaceutical that acts through heterodimerization of the FKBP12 and FRB fragment. Here, we aimed to insert a rapamycin inducible caspase 9 (riC9) gene in a safe harbor AAVS1 site to safeguard hiPSCs therapy by drug induced homodimerization. The donor vector containing an EF1α promoter, a FRB-FKBP-Caspase 9 (CARD domain) fusion protein and a puromycin resistant gene was constructed and co-transfected with sgRNA/Cas9 vector into hiPSCs. After one to two weeks screening with puromycin, single clones were collected for genotype and phenotype analysis. Finally, rapamycin was used to induce the homodimerization of caspase 9 to activate the apoptosis of the engineered cells. After transfection of hiPSCs followed by puromycin screening, five cell clones were collected. Genome amplification and sequencing showed that the donor DNA has been precisely knocked out at the endogenous AAVS1 site. The engineered hiPSCs showed normal pluripotency and proliferative capacity. Rapamycin induced caspase 9 activation, which led to the apoptosis of all engineered hiPSCs and its differentiated cells with different sensitivity to drugs. In conclusion, we generated a rapamycin-controllable hiPSCs survival by homodimerization of caspase 9 to turn on cell apoptosis. It provides a new strategy to guarantee the safety of the hiPSCs therapy.
Humans ; Induced Pluripotent Stem Cells ; Sirolimus/metabolism* ; Caspase 9/metabolism* ; RNA, Guide, CRISPR-Cas Systems ; Pluripotent Stem Cells/metabolism* ; Cell Differentiation ; Puromycin/metabolism*