Comparative study of the binding of 3 flavonoids to the fat mass and obesity-associated protein by spectroscopy and molecular modeling

Baicalein disrupts TGF-β-induced EMT in pancreatic cancer by FTO-dependent m6A demethylation of ZEB1

Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive malignancy associated with poor prognosis. Baicalein, a flavonoid extracted from the roots of Scutellaria baicalensis, traditionally used in Chinese medicine, has demonstrated potential in inhibiting cancer development and progression. However, its mechanism of action remains poorly understood, particularly regarding epigenetic gene regulation through m6A RNA methylation. In this study, three human PDAC cell lines and one nonmalignant cell line were employed. The effects of baicalein were examined using multiple assays, including RT-qPCR, MeRIP-qPCR, Western blotting, spheroid formation, RNA stability, and MTT, to evaluate cellular functions and m6A regulation. Baicalein significantly reduced cell viability, migration, invasion, and colony formation. It also downregulated FTO, an enzyme critical for m6A RNA demethylation. Knockdown of FTO replicated the effects of baicalein, underscoring its oncogenic role in PDAC. Bioinformatic analysis identified ZEB1-a key transcription factor in epithelial-to-mesenchymal transition-as an m6A-modified target regulated by FTO. Both baicalein treatment and FTO knockdown enhanced m6A modification and decreased ZEB1 mRNA stability, thereby suppressing stemness-related features. Rescue experiments further confirmed that baicalein disrupts the TGF-β/FTO/ZEB1 signaling axis, highlighting its therapeutic potential in PDAC. This study offers fundamental insights for the development of novel therapeutic strategies targeting PDAC.

Pancreatic lipase inhibitors: Virtual screening and mechanistic analysis

In this study, 3D-QSAR pharmacophore models were used to screen Chrysin (Chr), Genistein (Gen) and Naringenin (Nar) as inhibitors of pancreatic lipase (PL). The mechanisms of inhibition were explored using PL activity assays, enzyme kinetics, multispectral techniques, molecular docking, and molecular dynamics (MD) simulations, leading to the construction of a pharmacophore model that included two hydrogen bond acceptors and one hydrophobic group. Chr, Gen, and Nar competitively and reversibly inhibited PL with IC50 values of 22.98 ± 1.45, 42.36 ± 0.35, and 48.66 ± 0.25 μmol·L-1, respectively, and inhibition constants of (6.2995 ± 0.01) × 10-5, (6.5494 ± 0.02) × 10-5 and (2.4361 ± 0.02) × 10-5 mol·L-1, respectively. Kinetic analysis, fluorescence quenching assays and molecular docking showed that thee compounds interacted with PL close to its active site (Ser153-His264-Asp177), affecting the microenvironment of tryptophan residues, and bound stably to PL via hydrogen bonds, hydrophobic interactions, and van der Waals forces. UV-visible spectra showed binding constants of 65.40 × 103, 62.70 × 103 and 6.41 × 103 L/mol, respectively. MD simulations indicated that the structures of the complexes were compact, with binding free energy analysis ranking the PL inhibitory abilities of the compounds as Chr > Gen > Nar. In summary, the pharmacophore model was accurate. Chr, Gen, and Nar could inhibit PL activity. These findings provide a reference for the screening and development of new PL inhibitors.

Epigenetic Mechanisms in Osteoporosis: Exploring the Power of m6A RNA Modification

Osteoporosis, recognised as a metabolic disorder, has emerged as a significant burden on global health. Although available treatments have made considerable advancements, they remain inadequately addressed. In recent years, the role of epigenetic mechanisms in skeletal disorders has garnered substantial attention, particularly concerning m6A RNA modification. m6A is the most prevalent dynamic and reversible modification in eukaryotes, mediating various metabolic processes of mRNAs, including splicing, structural conversion, translation, translocation and degradation and serves as a crucial component of epigenetic modification. Research has increasingly validated that m6A plays a vital role in the proliferation, differentiation, migration, invasion,and repair of bone marrow mesenchymal stem cells (BMSCs), osteoblasts and osteoclasts, all of which impact the whole process of osteoporosis pathogenesis. Continuous efforts have been made to target m6A regulators and natural products derived from traditional medicine, which exhibit multiple biological activities such as anti-inflammatory and anticancer effects, have emerged as a valuable resources for m6A drug discovery. This paper elaborates on m6A methylation and its regulatory role in osteoporosis, emphasising its implications for diagnosis and treatment, thereby providing theoretical references.

Exploring the therapeutic mechanisms of millet in obesity through molecular docking, pharmacokinetics, and dynamic simulation

Obesity, a prevalent global health concern, is characterized by excessive fat accumulation, which confers significant nutritional and health risks, including a shortened lifespan and diminished wellbeing. Central to the regulation of energy balance and food intake is the fat mass and obesity-associated (FTO) protein, which modulates the interplay between caloric consumption and energy expenditure. Given its pivotal role in obesity regulation, the identification of effective inhibitors targeting the FTO protein is imperative for developing therapeutic interventions. Currently available anti-obesity drugs are often plagued by undesirable side effects. In contrast, natural plant-derived bioactive compounds are gaining prominence in the pharmaceutical industry due to their efficacy and lower incidence of adverse effects. Little Millet, a traditional cereal known for its rich nutritional profile and high satiety index, was investigated in this study using molecular docking and dynamics simulation approach for its potential as an anti-obesity agent. Our research demonstrates that four bioactive compounds from Little Millet exhibit superior binding energies ranging from 7.22 to 8.83 kcal/mol, compared to the standard anti-obesity drug, orlistat, which has a binding energy of 5.96 kcal/mol. These compounds fulfilled all drug-like criteria, including the Lipinski, Ghose, Veber, Egan, and Muegge rules, and exhibited favorable profiles in terms of distribution, metabolism, and prolonged half-life without toxicity. Conversely, orlistat was associated with hepatotoxicity, a reduced half-life, and multiple violations of drug-likeness parameters, undermining its efficacy. Molecular dynamics simulations and Gibbs free energy assessments revealed that the four identified compounds maintain stable interactions with key residues in the FTO protein's active site. We propose further validation through extensive In vitro, In vivo, and clinical studies to ascertain the therapeutic potential of these compounds in combating obesity.

Ramifications of m6A Modification on ncRNAs in Cancer

N6-methyladenosine (m6A) is an RNA modification wherein the N6-position of adenosine is methylated. It is one of the most prevalent internal modifications of RNA and regulates various aspects of RNA metabolism. M6A is deposited by m6A methyltransferases, removed by m6A demethylases, and recognized by reader proteins, which modulate splicing, export, translation, and stability of the modified mRNA. Recent evidence suggests that various classes of non- coding RNAs (ncRNAs), including microRNAs (miRNAs), circular RNAs (circRNAs), and long con-coding RNAs (lncRNAs), are also targeted by this modification. Depending on the ncRNA species, m6A may affect the processing, stability, or localization of these molecules. The m6A- modified ncRNAs are implicated in a number of diseases, including cancer. In this review, the author summarizes the role of m6A modification in the regulation and functions of ncRNAs in tumor development. Moreover, the potential applications in cancer prognosis and therapeutics are discussed.

Regulatory effects of natural products on N6-methyladenosine modification: A novel therapeutic strategy for cancer

N6-methyladenosine (m6A) is considered to be the most common and abundant epigenetics modification in messenger RNA (mRNA) and noncoding RNA. Abnormal modification of m6A is closely related to the occurrence, development, progression, and prognosis of cancer. m6A regulators have been identified as novel targets for anticancer drugs. Natural products, a rich source of traditional anticancer drugs, have been utilized for the development of m6A-targeting drugs. Here, we review the key role of m6A modification in cancer progression and explore the prospects and structural modification mechanisms of natural products as potential drugs targeting m6A modification for cancer treatment.

N6-methyladenosine methylation in ophthalmic diseases: From mechanisms to potential applications

N6-methyladenosine (m6A) modification, as the most common modification method in eukaryotes, is widely involved in numerous physiological and pathological processes, such as embryonic development, malignancy, immune regulation, and premature aging. Under pathological conditions of ocular diseases, changes in m6A modification and its metabolism can be detected in aqueous and vitreous humor. At the same time, an increasing number of studies showed that m6A modification is involved in the normal development of eye structures and the occurrence and progress of many ophthalmic diseases, especially ocular neovascular diseases, such as diabetic retinopathy, age-related macular degeneration, and melanoma. In this review, we summarized the latest progress regarding m6A modification in ophthalmic diseases, changes in m6A modification-related enzymes in various pathological states and their upstream and downstream regulatory networks, provided new prospects for m6A modification in ophthalmic diseases and new ideas for clinical diagnosis and treatment.

Epigenetic regulation by quercetin: a comprehensive review focused on its biological mechanisms

Epigenetics regulates gene expression and play significant roles across diverse disease states. Epigenetics mechanisms, including DNA methylation, histone modifications, microRNAs/lncRNA, and N6-methyladenosine (m6A) RNA methylation, elicit heritable but reversible modifications in gene expression without modifying the DNA sequence. Recent research suggests that certain natural phytochemicals with chemopreventive properties have the potential to function as epigenetic regulators. Quercetin, a derivative of natural flavonoid glycosides and a constituent of the human diet, is linked to a variety of health benefits including anti-inflammatory, anticancer activity, antiapoptotic, antihypertensive, and neuroprotective effects. Recent findings suggest that quercetin possesses the ability to modulate canonical biochemical signaling pathways and exert an impact on epigenetic networks. This review aims to synthesize the most recent research findings that elucidate the potential biological effects of quercetin and its influence on in vitro and in vivo models via epigenetic mechanisms. In light of our findings, it is evident that quercetin possesses the potential to function as an exemplary instance of naturally derived phytochemicals, which can be effectively employed as a pivotal constituent in functional foods and dietary supplements aimed at the amelioration of various ailments. More specifically, its mechanism of action involves the alteration of diverse epigenetic targets.

N6-methyladenosine (m6A) methylation in kidney diseases: Mechanisms and therapeutic potential

The N6-methyladenosine (m6A) modification is regulated by methylases, commonly referred to as "writers," and demethylases, known as "erasers," leading to a dynamic and reversible process. Changes in m6A levels have been implicated in a wide range of cellular processes, including nuclear RNA export, mRNA metabolism, protein translation, and RNA splicing, establishing a strong correlation with various diseases. Both physiologically and pathologically, m6A methylation plays a critical role in the initiation and progression of kidney disease. The methylation of m6A may also facilitate the early diagnosis and treatment of kidney diseases, according to accumulating research. This review aims to provide a comprehensive overview of the potential role and mechanism of m6A methylation in kidney diseases, as well as its potential application in the treatment of such diseases. There will be a thorough examination of m6A methylation mechanisms, paying particular attention to the interplay between m6A writers, m6A erasers, and m6A readers. Furthermore, this paper will elucidate the interplay between various kidney diseases and m6A methylation, summarize the expression patterns of m6A in pathological kidney tissues, and discuss the potential therapeutic benefits of targeting m6A in the context of kidney diseases.

RNA m6 A methylation in cancer

N⁶ -methyladenosine (m⁶ A) is one of the most abundant internal modifications in eukaryotic messenger RNAs (mRNAs) and non-coding RNAs (ncRNAs). It is a reversible and dynamic RNA modification that has been observed in both internal coding segments and untranslated regions. Studies indicate that m⁶ A modifications play important roles in translation, RNA splicing, export, degradation and ncRNA processing control. In this review, we focus on the profiles and biological functions of RNA m⁶ A methylation on both mRNAs and ncRNAs. The dynamic modification of m⁶ A and its potential roles in cancer development are discussed. Moreover, we discuss the possibility of m⁶ A modifications serving as potential biomarkers for cancer diagnosis and targets for therapy.

m6A modification: recent advances, anticancer targeted drug discovery and beyond

Abnormal N6-methyladenosine (m6A) modification is closely associated with the occurrence, development, progression and prognosis of cancer, and aberrant m6A regulators have been identified as novel anticancer drug targets. Both traditional medicine-related approaches and modern drug discovery platforms have been used in an attempt to develop m6A-targeted drugs. Here, we provide an update of the latest findings on m6A modification and the critical roles of m6A modification in cancer progression, and we summarize rational sources for the discovery of m6A-targeted anticancer agents from traditional medicines and computer-based chemosynthetic compounds. This review highlights the potential agents targeting m6A modification for cancer treatment and proposes the advantage of artificial intelligence (AI) in the discovery of m6A-targeting anticancer drugs. Three stages of m6A-targeting anticancer drug discovery: traditional medicine-based natural products, modern chemical modification or synthesis, and artificial intelligence (AI)-assisted approaches for the future.

Investigation into the mechanisms of quercetin-3-O-glucuronide inhibiting α-glucosidase activity and non-enzymatic glycation by spectroscopy and molecular docking

The inhibition of α-glucosidase and glycation is closely related to the treatment of type 2 diabetes mellitus (DM) and its complications. In this study, quercetin-3-O-glucuronide (Q3GA) showed reversible and mixed-mode inhibition of α-glucosidase activity, with an IC₅₀ value of 108.11 ± 4.61 μM. This was mainly due to the spontaneous formation of Q3GA-α-glucosidase driven by hydrogen bonding and van der Waals forces, which could change the microenvironments and conformation of α-glucosidase. In addition, Q3GA showed strong suppression of the formation of glycation products, including fructosamine, advanced glycation end products (AGEs), and 5-hydroxymethylfurfural (5-HMF). Molecular docking analysis demonstrated that Q3GA entered the hydrophobic pocket of ovalbumin to form six hydrogen bonds with amino acid residues, which affected the glycation process. These findings indicate that Q3GA is an excellent inhibitor of α-glucosidase and glycation, and promote its development as a drug or dietary supplement for DM.

Simultaneous changes of exogenous dissolved organic matter treated by ozonation in properties and interaction behavior with sulfonamides

Effluent is often treated with ozone before being discharged into a natural water environment. This process will change the interaction between effluent organic matter and pollutants in aquatic environment. The impact of ozonation on complexation between dissolved organic matter in such wastewater and sulfadimidine often found in natural water was studied in laboratory experiments using four types of real wastewater. Ozonation was found to decrease the proportion of organic matter with a molecular weight greater than 5 kDa as well as protein-like, fulvic-like and humic-like components, but except the proportion of hydrophilic components. The aromaticity of the dissolved organic matter was also reduced after ozonation. The complexation of tryptophan and tyrosine with sulfadimidine mainly depends on their hydrophobicity and large molecular weight. Ozonation of fulvic and humic acid tends to produce small and medium molecular weight hydrophilics. The complexation of humic and fulvic acids with sulfadimidine was enhanced by ozonation. Dissolved organic matter, with or without oxidation, were found to weaken sulfadimidine's inhibition of microbial growth, especially for Aeromonas and Acinetobacter species. This finding will expand our understanding about the impact of advanced treatment processes on the dissolved organic matters' properties in effluent.

In silico prediction, molecular docking and binding studies of acetaminophen and dexamethasone to Enterococcus faecalis diaminopimelate epimerase

Enterococcus faecalis (E. faecalis) is a Gram-positive coccoid, non-sporulating, facultative anaerobic, multidrug resistance bacterium responsible for almost 65% to 80% of all enterococcal nosocomial infections. It usually causes infective endocarditis, urinary tract and surgical wound infections. The increase in E. faecalis resistance to conventionally available antibiotic has rekindled intense interest in developing useful antibacterial drugs. In E. faecalis, diaminopimelate epimerase (DapF) is involved in the lysine biosynthetic pathway. The product of this pathway is precursors of peptidoglycan synthesis, which is a component of bacterial cell wall. Also, because mammals lack this enzyme, consequently E. faecalis diaminopimelate epimerase (EfDapF) represents a potential target for developing novel class of antibiotics. In this regard, we have successfully cloned, overexpressed the gene encoding DapF in BL-21(DE3) and purified with Ni-NTA Agarose resin. In addition to this, binding studies were performed using fluorescence spectroscopy in order to confirm the bindings of the identified lead compounds (acetaminophen and dexamethasone) with EfDapF. Docking studies revealed that acetaminophen found to make hydrogen bonds with Asn72 and Asn13 while dexamethasone interacted by forming hydrogen bonds with Asn205 and Glu223. Thus, biochemical studies indicated acetaminophen and dexamethasone, as potential inhibitors of EfDapF and eventually can reduce the catalytic activity of EfDapF.

Identification of tectoridin as the inhibitor of FTO by isothermal titration calorimetric and spectroscopic methods

The characteristics of binding between tectoridin and the fat mass and obesity-associated protein were investigated.

Metabolism and pharmacokinetics of a novel polyphenol fatty acid ester phloridzin docosahexaenoate in Balb/c female mice

Flavonoids are known to undergo phase II metabolism and produce metabolites with similar or stronger biological effects compared to the parent flavonoids. However, the limited cellular uptake and bioavailability restrict their clinical use. We synthesized phloridzin docosahexaenoate (PZ-DHA), a novel fatty acid ester of polyphenol, through an acylation reaction with the aim of increasing the cellular availability and stability of the parent biomolecules, phloridzin (PZ) and docosahexaenoic acid (DHA). Here, we report metabolites and pharmacokinetic parameters of PZ-DHA, determined using ultra-high-performance liquid chromatography-electrospray ionization tandem mass spectrometry. PZ-DHA was taken-up by human (MDA-MB-231, MDA-MB-468, and MCF-7) and mouse (4T1) mammary carcinoma and human non-malignant mammary epithelial cells (MCF-10A) in cellular uptake assays. Our results suggested that the acylation improves the cellular uptake of PZ and stability of DHA within cells. In mouse hepatic microsomal assays, two major glucuronides of PZ-DHA, PZ-DHA-4-O-glucuronide and PZ-DHA-4'-O-glucuronide (MW = 923.02 g/mol), were detected. One tri-methylated- (4,4',6'-O-trimethyl-PZ-DHA) (MW = 788.88 g/mol) and one di-sulphated- (PZ-DHA-4,4'-O-disulphide) PZ-DHA metabolite (MW = 906.20 g/mol) were also identified. Intraperitoneal injections of PZ-DHA (100 mg/kg) into Balb/c female mice was rapidly absorbed with a serum C_max and T_max of 23.7 µM and 60 min, respectively, and rapidly eliminated (t_1/2 = 28.7 min). PZ-DHA and its metabolites are readily distributed throughout the body (V_d = 57 mL) into many organs. We identified in vitro and in vivo metabolites of PZ-DHA, which could be tested for potential use to treat diseases such as cancer in multiple organ systems.

Isoliquiritigenin Enhances the Beige Adipocyte Potential of Adipose-Derived Stem Cells by JNK Inhibition

Human adipose-derived stem cells (hASCs) can be isolated from fat tissue and have attracted interest for their potential therapeutic applications in metabolic disease. hASCs can be induced to undergo adipogenic differentiation in vitro by exposure to chemical agents or inductive growth factors. We investigated the effects and mechanism of differentiating hASC-derived white adipocytes into functional beige and brown adipocytes with isoliquiritigenin (ILG) treatment. Here, we showed that hASC-derived white adipocytes could promote brown adipogenesis by expressing both uncoupling protein 1 (UCP1) and PR/SET Domain 16 (PRDM16) following low-dose ILG treatments. ILG treatment of white adipocytes enhanced the expression of brown fat-specific markers, while the expression levels of c-Jun N-terminal kinase (JNK) signaling pathway proteins were downregulated. Furthermore, we showed that the inhibition of JNK phosphorylation contributed to white adipocyte differentiation into beige adipocytes, which was validated by the use of SP600125. We identified distinct regulatory effects of ILG dose responses and suggested that low-dose ILG induced the beige adipocyte potential of hASCs via JNK inhibition.

Mass Spectrometry Imaging of Flavonols and Ellagic Acid Glycosides in Ripe Strawberry Fruit

Flavonols and ellagic acid glycosides are major phenolic compounds in strawberry fruit. They have antioxidant activity, show protective functions against abiotic and biotic stress, and provide health benefits. However, their spatial distribution in ripe fruit has not been understood. Therefore, matrix-assisted laser desorption/ionization (MALDI)-mass spectrometry imaging (MSI) was performed to investigate their distribution in fruit tissues. Using strawberry extract, five flavonols, namely, three kaempferols and two quercetins, and two ellagic acid glycosides, were tentatively identified by MALDI-tandem MS. To investigate the tentatively identified compounds, MALDI-MSI and tandem MS imaging (MS/MSI) analyses were performed. Kaempferol and quercetin glycosides showed similar distribution patterns. They were mainly found in the epidermis, while ellagic acid glycosides were mainly found in the achene and in the bottom area of the receptacle. These results suggested that the difference in distribution pattern between flavonols and ellagic acid glycosides depends on the difference between their aglycones. Seemingly, flavonols play a role in protective functions in the epidermis, while ellagic acid glycosides play a role in the achene and in the bottom side of the receptacle, respectively. These results demonstrated that MALDI-MSI is useful for distribution analysis of flavonols and ellagic acid glycosides in strawberry fruit.

Flavones as a Privileged Scaffold in Drug Discovery: Current Developments

BACKGROUND

Flavones are one of the main subclasses of flavonoids with diverse pharmacological properties. They have been reported to possess antimalarial, antimicrobial, anti-tuberculosis, anti-allergic, antioxidant, anti-inflammatory activities, among others.

OBJECTIVE

The present review summarizes the recent information on the pharmacological properties of naturally occurring and synthetic flavones.

METHODS

Scientific publications referring to natural and synthetic flavones in relation to their biological activities were hand-searched in databases such as SciFinder, PubMed (National Library of Medicine), Science Direct, Wiley, ACS, SciELO, Springer, among others.

RESULTS

As per the literature, seventy-five natural flavones were predicted as active compounds with reference to their IC50 (<20 µg/mL) in in vitro studies. Also, synthetic flavones were found active against several diseases.

CONCLUSION

As per the literature, flavones are important sources for the potential treatment of multifactorial diseases. However, efforts toward the development of flavone-based therapeutic agents are still needed. The appearance of new catalysts and chemical transformations is expected to provide avenues for the synthesis of unexplored flavones, leading to the discovery of flavones with new properties and biological activities.

Galangin inhibits α-glucosidase activity and formation of non-enzymatic glycation products

Inhibition of α-glucosidase and non-enzymatic glycation is considered as an effective approach to treat type 2 diabetes. Herein, multispectroscopic techniques and molecular docking analysis were used to investigate the inhibition of galangin on α-glucosidase and non-enzymatic glycation. Galangin showed a reversible inhibition on α-glucosidase activity in a mixed-type manner through a monophasic kinetic process, and induced the fluorescence quenching and conformational changes of α-glucosidase by forming α-glucosidase-galgangin complex. Molecular docking revealed that galangin primarily interacted with the amino acid residues within the active site of α-glucosidase, which may prevent the entrance of substrate resulting in a decrease in catalytic efficiency of α-glucosidase. Moreover, galangin moderately inhibited the formation of intermediates of non-enzymatic glycation, fructosamine and α-dicarbonyl compounds and strongly inhibited the formation of advanced glycation end products.