Dietary Luteolin: A Narrative Review Focusing on Its Pharmacokinetic Properties and Effects on Glycolipid Metabolism

Post-modification of covalent organic framework functionalized aminated carbon nanotubes with active site (Fe) for the sensitive detection of luteolin

In this research, the TT-COF(Fe)@NH2-CNTs was innovatively prepared through a post-modification synthetic process functionalized TT-COF@NH2-CNTs with active site (Fe), where TT-COF@NH2-CNTs was prepared via a one-pot strategy using 5,10,15,20-tetrakis (para-aminophenyl) porphyrin (TTAP), 2,3,6,7-tetra (4-formylphenyl) tetrathiafulvalene (TTF) and aminated carbon nanotubes (NH2-CNTs) as raw materials. The complex TT-COF(Fe)@NH2-CNTs material possessed porous structures, outstanding conductivity and rich catalytic sites. Thus, it can be adopted to construct electrochemical sensor with glassy carbon electrode (GCE). The TT-COF(Fe)@NH2-CNTs/GCE can selectively detect luteolin (Lu) with a wide linear plot ranging from 0.005 to 3 μM and a low limit of detection (LOD) of 1.45 nM (S/N = 3). The Lu residues in carrot samples were determined using TT-COF(Fe)@NH2-CNTs sensor and UV-visible (UV-Vis) approach. This TT-COF(Fe)@NH2-CNTs/GCE sensor paves the way for the quantification of Lu through a cost-efficient and sensitive electrochemical approach, which can make a significant step in the sensing field based on crystalline COFs.

Biosensor Based on ZIF-67-HRP and MWCNTs Nanocomposite Modified Glass Carbon Electrode for the Detection of Luteolin in Vegetables

Luteolin has various pharmacological properties, including anti-inflammatory, antioxidant, and antitumor characteristics. Due to its potential value in drugs and functional foods, it is important to develop an efficient method for detecting luteolin. In this work, the poor selectivity of existing luteolin nonenzymatic sensors was solved by translating the enzyme-catalyzed reaction from bulk solution to the surface of a horseradish peroxidase (HRP) modified electrode through an electrocatalytic oxidation process. Here, we modified the surface of a glassy carbon electrode (GCE) with metal-organic frameworks (MOFs; ZIF-67 here, abbreviated as ZIF), functional nanomaterials, and HRP and finally covered it with Nafion (NF). In this case, luteolin acts as a hydrogen donor, and the electrode acts as a hydrogen acceptor; the oxidation reaction occurs on the electrode surface. The use of ZIF-67 ensured the conformational stability of HRP to ensure the selectivity and anti-interference property, and SDS-dispersed multiwalled carbon nanotubes (MWCNTs) enhanced the electrode conductivity. The use of NF avoids shedding of the electrode material during the testing process. A UV-vis spectrophotometer was used to study the selectivity of luteolin by HRP and the compatibility between HRP and ZIF. The materials were characterized and analyzed by scanning electron microscopy and transmission electron microscopy. Due to the synergistic effect of these nanomaterials, the linear range of NF/ZIF-HRP/MWCNTs-SDS/GCE was 1.0 × 10-2 to 6.0 μM, with detection limits of 25.3 nM (S/N = 3). The biosensor showed long-term stability and reproducibility, with a relative standard deviation of 4.2% for the peak current (n = 5). Finally, the biosensor was successfully used to detect luteolin in carrots, celery, and cauliflower.

Therapeutic Potential of Luteolin for Diabetes Mellitus and Its Complications

The global prevalence of diabetes mellitus (DM) and its complications has been showing an upward trend in the past few decades, posing an increased economic burden to society and a serious threat to human life and health. Therefore, it is urgent to investigate the effectiveness of complementary and alternative therapies for DM and its complications. Luteolin is a kind of polyphenol flavonoid with widely existence in some natural resources, as a safe dietary supplement, it has been widely studied and reported in the treatment of DM and its complications. This review demonstrates the therapeutic potential of luteolin in DM and its complications, and elucidates the action mode of luteolin at the molecular level. It is characterized by anti-inflammatory, antioxidant, and neuroprotective effects. In detail, luteolin can not only improve endothelial function, insulin resistance and β-cell dysfunction, but also inhibit the activities of dipeptidyl peptidase-4 and α-glucosidase. However, due to the low water solubility and oral bioavailability of luteolin, its application in the medical field is limited. Therefore, great importance should be attached to the joint application of luteolin with current advanced science and technology. And more high-quality human clinical studies are needed to clarify the effects of luteolin on DM patients.

Hong Guo Ginseng Guo (HGGG) protects against kidney injury in diabetic nephropathy by inhibiting NLRP3 inflammasome and regulating intestinal flora

BACKGROUND

Diabetic nephropathy (DN) is one of the most serious complications of diabetes which leads to end-stage renal failure and approximately one-third of patients need dialysis. There is still a lack of effective and specific treatment for DN. Searching new drugs from natural foods is an alternative approach to treat diabetes and its complications. Hong Guo Ginseng Guo (HGGG), a berry with palatability and nutritional benefits, has exhibited medicinal properties to mitigate the progression of DN.

PURPOSE

This study investigates the effects of HGGG on streptozotocin (STZ)-induced diabetic nephropathy (DN) in rats and elucidates the mechanisms underlying its reno-protective and diabetes management benefits.

METHODS

The LC-MS spectra method identified the primary ingredients in HGGG. To induce DN, male Sprague-Dawley (SD) rats received a single intraperitoneal injection of 75 mg/kg STZ. Over an eight-week treatment period, we assessed biochemical parameters including blood glucose, urine albumin-to-creatinine ratio (UACR), blood urea nitrogen (BUN), and urine N-acetyl-beta-d-glucosaminidase (NAG). Tissue pathology was examined using Masson's trichrome, Periodic Acid-Schiff (PAS), and Hematoxylin-Eosin (H&E) stains. We analyzed pro-inflammatory mediators and tissue fibrosis extent using Western blotting and immunohistochemistry. Gut microbiota composition was characterized via 16S rDNA sequencing.

RESULTS

Seventeen chemical compounds were identified, with lobetyolin, luteolin, and rutin highlighted as the primary active elements. HGGG extract appeared to confer renal protection, demonstrated by improvements in UACR, BUN, and urine NAG levels. The reno protective effects in HGGG-treated DN rats were linked to reduced renal fibrosis and inhibition of the NLRP3 inflammasome. Additionally, HGGG administration improved gut barrier integrity and altered the gut microbiota in DN rats, increasing the relative abundance of beneficial bacteria known for regulating polyamines and producing short-chain fatty acids (SCFAs), including Ruminococcus, Barnesiella_sp, Anaerovoracaceae, and Prevotellaceae_NK3B31. Meanwhile, treatment with HGGG decreasing the presence of Oscillospira, potential pathogens responsible for producing lipopolysaccharide (LPS).

CONCLUSION

HGGG has potential as a beneficial fruit for managing diabetes and its associated complications through modulation of the gut microbiota.

Network analysis and experimental verification of Salvia miltiorrhiza Bunge-Reynoutria japonica Houtt. drug pair in the treatment of non-alcoholic fatty liver disease

CONTEXT

There are currently no approved specific clinical drugs for non-alcoholic fatty liver disease (NAFLD). Salvia miltiorrhiza Bunge-Reynoutria japonica Houtt. drug pair (SRDP) has been widely used in the treatment of chronic liver diseases. However, the mechanism of SRDP treating NAFLD remains unclear.

OBJECTIVE

Based on network analysis and in vitro experimental verification, we investigated the effect of SRDP on lipid deposition and explored its possible mechanism for the treatment of NAFLD.

METHODS

The TCMSP platform was used to screen the active metabolites of SRDP and corresponding targets. The GeneCards and OMIM databases were used to screen the NAFLD targets. The drug-disease intersecting targets were extracted to obtain the potential targets. Then the protein-protein interaction (PPI) and drug-active metabolites-target-disease network map was constructed. The DAVID database was performed to GO and KEGG pathway enrichment analysis for the intersecting targets. The core active metabolite and signaling pathway were verified by in vitro experiments.

RESULTS

Network analysis predicted 59 active metabolites and 89 targets of SRDP for the treatment of NAFLD. 112 signaling pathways were enriched for KEGG pathways, including PI3K-AKT signaling pathway,etc. It was confirmed that luteolin, the core active metabolite of SRDP, effectively reduced fat accumulation and intracellular triglyceride content in HepG2 fatty liver cell model. Luteolin could inhibit mTOR pathway by inhibiting PI3K-AKT signaling pathway phosphorylation, thereby activating autophagy to alleviate NAFLD. DISCUSSION AND CONCLUSION: The results of this study validate and predict the possible role of various active metabolites of SRDP in the treatment of NAFLD through multiple targets and signaling pathways. The core active metabolite of SRDP, luteolin can alleviate NAFLD by acting on the PI3K-AKT-mTOR signaling pathway to induce autophagy.

Exploring the pharmacological mechanism of Xianlingubao against diabetic osteoporosis based on network pharmacology and molecular docking: An observational study

Xianlinggubao formula (XLGB), is a traditional Chinese compound Medicine that has been extensively used in osteoarthritis and aseptic osteonecrosis, but its curative effect on diabetic osteoporosis (DOP) and its pharmacological mechanisms remains not clear. The aim of the present study was to investigate the possible mechanism of drug repurposing of XLGB in DOP therapy. We acquired XLGB active compounds from the traditional Chinese medicine systems pharmacology and traditional Chinese medicines integrated databases and discovered potential targets for these compounds by conducting target fishing using the traditional Chinese medicine systems pharmacology and Swiss Target Prediction databases. Gene Cards and Online Mendelian Inheritance in Man® database were used to identify the DOP targets. Overlapping related targets between XLGB and DOP was selected to build a protein-protein interaction network. Next, the Metascape database was utilized to enrich the Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathways. In addition, Auto-Dock Vina software was used to verify drug and target binding. In total, 48 hub targets were obtained as the candidate targets responsible for DOP therapy. The anti-DOP effect mediated by XLGB was primarily centralized on the advanced glycation end products (AGEs)-receptor for AGE signaling pathway in diabetic complications and osteoclast differentiation. In addition, AKT serine/threonine kinase 1, tumor necrosis factor, Interleukin-6, vascular endothelial growth factor A and peroxisome proliferator activated receptor gamma, which were considered as potential therapeutic targets. Furthermore, molecular docking results confirm the credibility of the predicted therapeutic targets. This study elucidates that XLGB may through regulating AGEs formation and osteoclast differentiation as well as angiogenesis and adipogenesis against DOP. And this study provides new promising points to find the exact regulatory mechanisms of XLGB mediated anti-DOP effect.

Baicalein: A potential GLP-1R agonist improves cognitive disorder of diabetes through mitophagy enhancement

There is increasing evidence that the activation of glucagon-like peptide-1 receptor (GLP-1R) can be used as a therapeutic intervention for cognitive disorders. Here, we have screened GLP-1R targeted compounds from Scutellaria baicalensis, which revealed baicalein is a potential GLP-1R small-molecule agonist. Mitophagy, a selective autophagy pathway for mitochondrial quality control, plays a neuroprotective role in multiple cognitive impairment diseases. We noticed that Glp1r knock-out (KO) mice present cognitive impairment symptoms and appear worse in spatial learning memory and learning capacity in Morris water maze (MWM) test than their wide-type (WT) counterparts. Our mechanistic studies revealed that mitophagy is impaired in hippocampus tissue of diabetic mice and Glp1r KO mice. Finally, we verified that the cognitive improvement effects of baicalein on diabetic cognitive dysfunction occur through the enhancement of mitophagy in a GLP-1R-dependent manner. Our findings shed light on the importance of GLP-1R for cognitive function maintenance, and revealed the vital significance of GLP-1R for maintaining mitochondrial homeostasis. Furthermore, we identified the therapeutic potential of baicalein in the treatment of cognitive disorder associated with diabetes.

Dietary intake of luteolin is negatively associated with all-cause and cardiovascular mortality in chronic kidney disease patients

BACKGROUND

Luteolin (Lut), a flavonoid present in the daily diet, exhibits potent anti-inflammatory and renoprotective effects. However, the association between Lut and chronic kidney disease (CKD) remains uncertain. The objective of this study is to explore the potential correlation.

METHODS

A total of 2,393 CKD patients were enrolled in a prospective cohort in the National Health and Nutrition Examination Survey (NHANES). A 24-h dietary recall was utilized to estimate the intake of dietary Lut based on the type and amount of food consumed. The National Death Index mortality data was utilized to ascertain all-cause and cardiac mortality (as of December 27, 2023). Cox proportional hazards model was used to estimate the relationship between Lut intake and mortality risk.

RESULTS

The median Lut intake was 0.305 mg/day, with interquartile range was 0.105-0.775 mg/day. During the follow-up period (median, 93 months), 682 all-cause deaths (217 cardiovascular disease [CVD] deaths) were recorded. Per unit increase in Lut intake reduced all-cause mortality by 27% (P < 0.001) and cardiac mortality by 34% (P = 0.01) in CKD patients. There was an inverse dose-response association between Lut intake (range: 0-8.945 mg/day) and mortality risk. Consistent results were also shown when stratified by age, sex, race, marital status, body mass index, CKD stage, urine protein creatinine ratio strata, CKD progression risk, hypertension, and CVD.

CONCLUSION

Dietary Lut intake is associated with a reduction in all-cause and cardiac mortality among CKD patients, potentially attributable to the anti-inflammatory characteristics of Lut.

A novel electrochemical sensor for detection of luteolin in food based on 3D networked electrically interconnected SiO2@GO/MXene composite

Luteolin (Lu), a compound with various biochemical and pharmacological activities beneficial to human health, has attracted researchers' attention. This study proposes an efficient and scalable method using ultrasound to intercalate graphene oxide (GO)-coated silica spheres (SiO2) into MXenes, resulting in a 3D conductive interconnected structural composite material. Characterization of the composite material was conducted using SEM, TEM, XRD, XPS, and Raman spectroscopy. MXenes exhibit excellent electrical conductivity, and the SiO2@GO surface with abundant hydroxyl and silanol groups provides high-binding active sites that facilitate Lu molecule enrichment. The formation of the 3D conductive interconnected structural composites enhances charge transport, significantly improving sensor sensitivity. Consequently, the sensor demonstrates excellent detection capabilities (detection range 0.03-7000 nM, detection limit 12 pM). Furthermore, the sensor can be applied to quantitative determination of Lu in real samples, including chrysanthemums, Jiaduobao, honeysuckle, purple perilla, and peanut shells, achieving recoveries between 98.2 and 104.7%.

Phytonutrients in the promotion of healthspan: a new perspective

Considering a growing, aging population, the need for interventions to improve the healthspan in aging are tantamount. Diet and nutrition are important determinants of the aging trajectory. Plant-based diets that provide bioactive phytonutrients may contribute to offsetting hallmarks of aging and reducing the risk of chronic disease. Researchers now advocate moving toward a positive model of aging which focuses on the preservation of functional abilities, rather than an emphasis on the absence of disease. This narrative review discusses the modulatory effect of nutrition on aging, with an emphasis on promising phytonutrients, and their potential to influence cellular, organ and functional parameters in aging. The literature is discussed against the backdrop of a recent conceptual framework which describes vitality, intrinsic capacity and expressed capacities in aging. This aims to better elucidate the role of phytonutrients on vitality and intrinsic capacity in aging adults. Such a review contributes to this new scientific perspective-namely-how nutrition might help to preserve functional abilities in aging, rather than purely offsetting the risk of chronic disease.

Luteolin: A promising multifunctional natural flavonoid for human diseases

Natural products are closely associated with human health. Luteolin (LUT), a flavonoid polyphenolic compound, is widely found in fruits, vegetables, flowers, and herbs. It is noteworthy that LUT exhibits a variety of beneficial pharmacological properties and holds significant potential for clinical applications, particularly in antitumor, anti-convulsion, diabetes control, anti-inflammatory, neuroprotection, anti-oxidation, anti-cardiovascular, and other aspects. The potential mechanism of action has been partially elucidated, including the mediation of NF-κB, toll-like receptor, MAPK, Wnt/β-catenin, PI3K/Akt, AMPK/mTOR, and Nrf-2, among others. The review that aimed to comprehensively consolidate essential information on natural sources, pharmacological effects, therapeutic and preventive potential, as well as potential mechanisms of LUT. The objective is to establish a theoretical basis for the continued development and application of LUT.

Luteolin as a potential therapeutic candidate for lung cancer: Emerging preclinical evidence

Lung cancer is a prevalent malignant tumor and a leading cause of cancer-related fatalities globally. However, current treatments all have limitations. Therefore, there is an urgent need to identify a readily available therapeutic agent to counteract lung cancer development and progression. Luteolin is a flavonoid derived from vegetables and herbs that possesses preventive and therapeutic effects on various cancers. With the goal of providing new directions for the treatment of lung cancer, we review here the recent findings on luteolin so as to provide new ideas for the development of new anti-lung cancer drugs. The search focused on studies published between January 1995 and January 2024 that explored the use of luteolin in lung cancer. A comprehensive literature search was conducted in the SCOPUS, Google Scholar, PubMed, and Web of Science databases using the keywords "luteolin" and "lung cancer." By collecting previous literature, we found that luteolin has multiple mechanisms of therapeutic effects, including promotion of apoptosis in lung cancer cells; inhibition of tumor cell proliferation, invasion and metastasis; and modulation of immune responses. In addition, it can be used as an adjuvant to radio-chemotherapy and helps to ameliorate cancer complications. This review summarizes the structure, natural sources, physicochemical properties and pharmacokinetics of luteolin, and focuses on the anti-lung cancer mechanism of luteolin, so as to provide new ideas for the development of new anti-lung cancer drugs.

Encapsulation of luteolin by self-assembled Rha/SSPS/SPI nano complexes: Characterization, stability, and gastrointestinal digestion in vitro

Luteolin has anti-inflammatory, antioxidant, and anti-tumor functions, but its poor water solubility and stability limit its applications in foods as a functional component. In this study, the nanocomposites loading luteolin (Lut) with soybean protein isolate (SPI), soluble soybean polysaccharide (SSPS) and/or rhamnolipid (Rha) were prepared by layer-by-layer shelf assembly method, and their properties were also evaluated. The results showed that Rha/SPI/Lut had the smallest particle size (206.24 nm) and highest loading ratio (8.03 μg/mg) while Rha/SSPS/SPI/Lut had the highest encapsulation efficiency (82.45 %). Rha interacted with SPI through hydrophobic interactions as the main driving force, while SSPS attached to SPI with only hydrogen bonding. Furthermore, the synergistic effect between Rha and SSPS was observed in Rha/SSPS/SPI/Lut complex, in consequence, it had the best thermal and storage stability, and the slowest release in gastrointestinal digestion. Thus, this approach provided an alternative way for the application of luteolin in functional foods.

A narrative review on the mechanism of natural flavonoids in improving glucolipid metabolism disorders

Glucolipid metabolism disorder (GLMD) is a complex chronic disease characterized by glucose and lipid metabolism disorders with a complex and diverse etiology and rapidly increasing incidence. Many studies have identified the role of flavonoids in ameliorating GLMD, with mechanisms related to peroxisome proliferator-activated receptors, nuclear factor kappa-B, AMP-activated protein kinase, nuclear factor (erythroid-derived 2)-like 2, glucose transporter type 4, and phosphatidylinositol-3-kinase/protein kinase B pathway. However, a comprehensive summary of the flavonoid effects on GLMD is lacking. This study reviewed the roles and mechanisms of natural flavonoids with different structures in the treatment of GLMD reported globally in the past 5 years and provides a reference for developing flavonoids as drugs for treating GLMD.

Discussion on the mechanism of Tiaoqi Xiaowei decoction in the treatment of chronic atrophic gastritis based on network pharmacology and molecular docking: An observational study

To explore the mechanism of Tiaoqi Xiaowei decoction in the treatment of chronic atrophic gastritis by network pharmacology and molecular docking. The main active components and targets of Tiaoqi Xiaowei decoction were obtained from TCMSP database. The databases of Disgenet, GeneCards, and OMIM were used to obtain chronic atrophic gastritis-related targets. The component-target-disease network was constructed by Cytoscape 3.7.1 software, and the protein-protein interaction network was constructed by String database. The core targets were screened by CytoNCA plug-in. Gene ontology analysis and Kyoto Encyclopedia of Genes and Genome pathway enrichment analysis were performed using the Metascape database. The core components and targets were subjected to molecular docking verification using AutoDock Tools 1.5.6 software, and the binding score was obtained. A total of 48 active components were identified, involving 82 action targets. Core active components such as quercetin, beta-sitosterol, kaempferol, luteolin, and naringenin, and core targets such as AKT1, TP53, VEGFA, TNF, IL6, and PTGS2 were obtained. A total of 188 signaling pathways were screened out, including cancer pathway, PI3K-Akt, IL-17, and TNF signaling pathway. Molecular docking results showed that the key components of Tiaoqi Xiaowei decoction had a favorable binding affinity with key targets. Tiaoqi Xiaowei decoction acts on multiple targets such as AKT1, TP53, VEGFA, TNF, IL6, PTGS2, and synergistically treats chronic atrophic gastritis by regulating inflammatory responses and tumor-related signaling pathways.

Natural Product-Derived Compounds Targeting Keratinocytes and Molecular Pathways in Psoriasis Therapeutics

Psoriasis is a chronic autoimmune inflammatory skin disorder that affects approximately 2-3% of the global population due to significant genetic predisposition. It is characterized by an uncontrolled growth and differentiation of keratinocytes, leading to the formation of scaly erythematous plaques. Psoriasis extends beyond dermatological manifestations to impact joints and nails and is often associated with systemic disorders. Although traditional treatments provide relief, their use is limited by potential side effects and the chronic nature of the disease. This review aims to discuss the therapeutic potential of keratinocyte-targeting natural products in psoriasis and highlight their efficacy and safety in comparison with conventional treatments. This review comprehensively examines psoriasis pathogenesis within keratinocytes and the various related signaling pathways (such as JAK-STAT and NF-κB) and cytokines. It presents molecular targets such as high-mobility group box-1 (HMGB1), dual-specificity phosphatase-1 (DUSP1), and the aryl hydrocarbon receptor (AhR) for treating psoriasis. It evaluates the ability of natural compounds such as luteolin, piperine, and glycyrrhizin to modulate psoriasis-related pathways. Finally, it offers insights into alternative and sustainable treatment options with fewer side effects.

Development of dietary small molecules as multi-targeting treatment strategies for Alzheimer's disease

Cognitive dysfunction can occur both in normal aging and age-related neurological disorders, such as mild cognitive impairment and Alzheimer's disease (AD). These disorders have few treatment options due to side effects and limited efficacy. New approaches to slow cognitive decline are urgently needed. Dietary interventions (nutraceuticals) have received considerable attention because they exhibit strong neuroprotective properties and may help prevent or minimize AD symptoms. Biological aging is driven by a series of interrelated mechanisms, including oxidative stress, neuroinflammation, neuronal apoptosis, and autophagy, which function through various signaling pathways. Recent clinical and preclinical studies have shown that dietary small molecules derived from natural sources, including flavonoids, carotenoids, and polyphenolic acids, can modulate oxidative damage, cognitive impairments, mitochondrial dysfunction, neuroinflammation, neuronal apoptosis, autophagy dysregulation, and gut microbiota dysbiosis. This paper reviews research on different dietary small molecules and their bioactive constituents in the treatment of AD. Additionally, the chemical structure, effective dose, and specific molecular mechanisms of action are comprehensively explored. This paper also discusses the advantages of using nanotechnology-based drug delivery, which significantly enhances oral bioavailability, safety, and therapeutic effect, and lowers the risk of adverse effects. These agents have considerable potential as novel and safe therapeutic agents that can prevent and combat age-related AD.

Fabrication of the Rapid Self-Assembly Hydrogels Loaded with Luteolin: Their Structural Characteristics and Protection Effect on Ulcerative Colitis

Luteolin (LUT) is a fat-soluble flavonoid known for its strong antioxidant and anti-inflammatory properties. Nonetheless, its use in the food industry has been limited due to its low water solubility and bioavailability. In this study, hyaluronic acid, histidine, and luteolin were self-assembled to construct tubular network hydrogels (HHL) to improve the gastrointestinal stability, bioavailability, and stimulation response of LUT. As anticipated, the HHL hydrogel's mechanical strength and adhesion allow it to withstand the challenging gastrointestinal environment and effectively extend the duration of drug presence in the body. In vivo anti-inflammatory experiments showed that HHL hydrogel could successfully alleviate colitis induced by dextran sulfate sodium (DSS) in mice by reducing intestinal inflammation and restoring the integrity of the intestinal barrier. Moreover, HHL hydrogel also regulated the intestinal microorganisms of mice and promoted the production of short-chain fatty acids. The HHL hydrogel group demonstrated a notably superior treatment effect compared to the LUT group alone. The hydrogel delivery system is a novel method to improve the absorption of LUT, increasing its bioavailability and enhancing its pharmaceutical effects.

Roles of flavonoids in ischemic heart disease: Cardioprotective effects and mechanisms against myocardial ischemia and reperfusion injury

BACKGROUND

Flavonoids are extensively present in fruits, vegetables, grains, and medicinal plants. Myocardial ischemia and reperfusion (MI/R) comprise a sequence of detrimental incidents following myocardial ischemia. Research indicates that flavonoids have the potential to act as cardioprotective agents against MI/R injuries. Several specific flavonoids, e.g., luteolin, hesperidin, quercetin, kaempferol, and puerarin, have demonstrated cardioprotective activities in animal models.

PURPOSE

The objective of this review is to identify the cardioprotective flavonoids, investigate their mechanisms of action, and explore their application in myocardial ischemia.

METHODS

A search of PubMed database and Google Scholar was conducted using keywords "myocardial ischemia" and "flavonoids". Studies published within the last 10 years reporting on the cardioprotective effects of natural flavonoids on animal models were analyzed.

RESULTS

A total of 55 natural flavonoids were identified and discussed within this review. It can be summarized that flavonoids regulate the following main strategies: antioxidation, anti-inflammation, calcium modulation, mitochondrial protection, ER stress inhibition, anti-apoptosis, ferroptosis inhibition, autophagy modulation, and inhibition of adverse cardiac remodeling. Additionally, the number and position of OH, 3'4'-catechol, C2=C3, and C4=O may play a significant role in the cardioprotective activity of flavonoids.

CONCLUSION

This review serves as a reference for designing a daily diet to prevent or reduce damages following ischemia and screening of flavonoids for clinical application.

Targeting CD73 with flavonoids inhibits cancer stem cells and increases lymphocyte infiltration in a triple-negative breast cancer mouse model

Introduction

Chemotherapy remains the mainstay treatment for triple-negative breast cancer (TNBC) due to the lack of specific targets. Given a modest response of immune checkpoint inhibitors in TNBC patients, improving immunotherapy is an urgent and crucial task in this field. CD73 has emerged as a novel immunotherapeutic target, given its elevated expression on tumor, stromal, and specific immune cells, and its established role in inhibiting anti-cancer immunity. CD73-generated adenosine suppresses immunity by attenuating tumor-infiltrating T- and NK-cell activation, while amplifying regulatory T cell activation. Chemotherapy often leads to increased CD73 expression and activity, further suppressing anti-tumor immunity. While debulking the tumor mass, chemotherapy also enriches heterogenous cancer stem cells (CSC), potentially leading to tumor relapse. Therefore, drugs targeting both CD73, and CSCs hold promise for enhancing chemotherapy efficacy, overcoming treatment resistance, and improving clinical outcomes. However, safe and effective inhibitors of CD73 have not been developed as of now.

Methods

We used in silico docking to screen compounds that may be repurposed for inhibiting CD73. The efficacy of these compounds was investigated through flow cytometry, RT-qPCR, CD73 activity, cell viability, tumorsphere formation, and other in vitro functional assays. For assessment of clinical translatability, TNBC patient-derived xenograft organotypic cultures were utilized. We also employed the ovalbumin-expressing AT3 TNBC mouse model to evaluate tumor-specific lymphocyte responses.

Results

We identified quercetin and luteolin, currently used as over-the-counter supplements, to have high in silico complementarity with CD73. When quercetin and luteolin were combined with the chemotherapeutic paclitaxel in a triple-drug regimen, we found an effective downregulation in paclitaxel-enhanced CD73 and CSC-promoting pathways YAP and Wnt. We found that CD73 expression was required for the maintenance of CD44highCD24low CSCs, and co-targeting CD73, YAP, and Wnt effectively suppressed the growth of human TNBC cell lines and patient-derived xenograft organotypic cultures. Furthermore, triple-drug combination inhibited paclitaxel-enriched CSCs and simultaneously improved lymphocyte infiltration in syngeneic TNBC mouse tumors.

Discussion

Conclusively, our findings elucidate the significance of CSCs in impairing anti-tumor immunity. The high efficacy of our triple-drug regimen in clinically relevant platforms not only underscores the importance for further mechanistic investigations but also paves the way for potential development of new, safe, and cost-effective therapeutic strategies for TNBC.

Elucidation of the anti-β-cell dedifferentiation mechanism of a modified Da Chaihu Decoction by an integrative approach of network pharmacology and experimental verification

ETHNOPHARMACOLOGICAL RELEVANCE

Modified Da Chaihu decoction (MDCH) is a traditional Chinese herbal prescription that has been used in the clinic to treat type 2 diabetes (T2D). Previous studies have confirmed that MDCH improves glycemic and lipid metabolism, enhances pancreatic function, and alleviates insulin resistance in patients with T2D and diabetic rats. Evidence has demonstrated that MDCH protects pancreatic β cells via regulating the gene expression of sirtuin 1 (SIRT1) and forkhead box protein O1 (FOXO1). However, the detailed mechanism remains unclear.

AIM OF THE STUDY

Dedifferentiation of pancreatic β cells mediated by FOXO1 has been recognized as the main pathogenesis of T2D. This study aims to investigate the therapeutic effects of MDCH on T2D in vitro and in vivo to elucidate the potential molecular mechanisms.

MATERIALS AND METHODS

To predict the key targets of MDCH in treating T2D, network pharmacology methods were used. A T2D model was induced in diet-induced obese (DIO) C57BL/6 mice with a single intraperitoneal injection of streptozotocin. Glucose metabolism indicators (oral glucose tolerance test, insulin tolerance test), lipid metabolism indicators (total cholesterol, triglyceride, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol), inflammatory factors (C-reactive protein, interleukin 6, tumor necrosis factor alpha), oxidative stress indicators (total antioxidant capacity, superoxide dismutase, malondialdehyde), and hematoxylin and eosin staining were analyzed to evaluate the therapeutic effect of MDCH on T2D. Immunofluorescence staining and quantification of FOXO1, pancreatic and duodenal homeobox 1 (PDX1), NK6 homeobox 1 (NKX6.1), octamer-binding protein 4 (OCT4), neurogenin 3 (Ngn3), insulin, and SIRT1, and Western blot analysis of insulin, SIRT1, and FOXO1 were performed to investigate the mechanism by which MDCH inhibited pancreatic β-cell dedifferentiation.

RESULTS

The chemical ingredients identified in MDCH were predicted to be important for signaling pathways related to lipid metabolism and insulin resistance, including lipids in atherosclerosis, the advanced glycation end product receptor of the advanced glycation end product signaling pathway, and the FOXO signaling pathway. Experimental studies showed that MDCH improved glucose and lipid metabolism in T2D mice, alleviated inflammation and oxidative stress damage, and reduced pancreatic pathological damage. Furthermore, MDCH upregulated the expression levels of SIRT1, FOXO1, PDX1, and NKX6.1, while downregulating the expression levels of OCT4 and Ngn3, which indicated that MDCH inhibited pancreatic dedifferentiation of β cells.

CONCLUSIONS

MDCH has therapeutic effects on T2D, through regulating the SIRT1/FOXO1 signaling pathway to inhibit pancreatic β-cell dedifferentiation, which has not been reported previously.

Inhibitory interaction of flavonoids with organic anion transporter 3 and their structure-activity relationships for predicting nephroprotective effects

The organic anion transporter 3 (OAT3), an important renal uptake transporter, is associated with drug-induced acute kidney injury (AKI). Screening and identifying potent OAT3 inhibitors with little toxicity in natural products, especially flavonoids, in reducing OAT3-mediated AKI is of great value. The five strongest OAT3 inhibitors from the 97 flavonoids markedly decreased aristolochic acid I-induced cytotoxicity and alleviated methotrexate-induced nephrotoxicity. The pharmacophore model clarified hydrogen bond acceptors and hydrophobic groups are the critical pharmacophores. These findings would provide valuable information in predicting the potential risks of flavonoid-containing food/herb-drug interactions and optimizing flavonoid structure to alleviate OAT3-related AKI.

Luteolin blocks the ROS/PI3K/AKT pathway to inhibit mesothelial-mesenchymal transition and reduce abdominal adhesions

BACKGROUND

Postoperative abdominal adhesion (PAA) is a common postoperative complication. Clinically, various methods have been used to prevent the occurrence of PAA, such as drugs and physiotherapy; however, no satisfactory results have been obtained. Luteolin (LUT) is a natural flavonoid that reduces inflammation and acts as an antioxidant. This research aimed to examine the impact and mechanism of LUT in reducing PAA.

METHODS

C57/BL6 mice were used in vivo experiments. PAA model was established using a brush friction method. Visual scoring and hematoxylin and eosin staining were used to score the severity of adhesions. Network pharmacology was used to infer potential targets and core pathways of LUT. Hydrogen peroxide (H2O2) was used to induce oxidative stress in vitro, while the reactive oxygen species (ROS) assay kit was used to evaluate oxidative stress levels. Western blotting, cell immunofluorescence, and multiple immunofluorescence assays were used to detect α-SMA, vimentin, E-cadherin, collagen I, or AKT phosphorylation level. Scratch assay was used to detect cell migration.

RESULTS

LUT reduced the degree of PAA in mice. It attenuated H2O2-induced ROS production and reversed mesothelial-mesenchymal transition (MMT) in HMrSV5 cells. Network pharmacology analysis showed that LUT likely exerted anti-adhesion activity by regulating the PI3K-Akt signaling pathway. Phosphorylated Akt levels were significantly reduced in LUT-treated HMrSV5 cells. LUT also significantly reduced the expression of vimentin and collagen I in adherent tissues and upregulated E-cadherin expression.

CONCLUSION

LUT blocks the ROS/PI3K/AKT pathway, thereby inhibiting MMT and reducing PAA. To this end, LUT has potential in PAA therapy.

Luteolin, a flavone ingredient: Anticancer mechanisms, combined medication strategy, pharmacokinetics, clinical trials, and pharmaceutical researches

Current pharmaceutical research is energetically excavating the pharmacotherapeutic role of herb-derived ingredients in multiple malignancies' targeting. Luteolin is one of the major phytochemical components that exist in various traditional Chinese medicine or medical herbs. Mounting evidence reveals that this phytoconstituent endows prominent therapeutic actions on diverse malignancies, with the underlying mechanisms, combined medication strategy, and pharmacokinetics elusive. Additionally, the clinical trial and pharmaceutical investigation of luteolin remain to be systematically delineated. The present review aimed to comprehensively summarize the updated information with regard to the anticancer mechanism, combined medication strategies, pharmacokinetics, clinical trials, and pharmaceutical researches of luteolin. The survey corroborates that luteolin executes multiple anticancer effects mainly by dampening proliferation and invasion, spurring apoptosis, intercepting cell cycle, regulating autophagy and immune, inhibiting inflammatory response, inducing ferroptosis, and pyroptosis, as well as epigenetic modification, and so on. Luteolin can be applied in combination with numerous clinical anticarcinogens and natural ingredients to synergistically enhance the therapeutic efficacy of malignancies while reducing adverse reactions. For pharmacokinetics, luteolin has an unfavorable oral bioavailability, it mainly persists in plasma as glucuronides and sulfate-conjugates after being metabolized, and is regarded as potent inhibitors of OATP1B1 and OATP2B1, which may be messed with the pharmacokinetic interactions of miscellaneous bioactive substances in vivo. Besides, pharmaceutical innovation of luteolin with leading-edge drug delivery systems such as host-guest complexes, nanoparticles, liposomes, nanoemulsion, microspheres, and hydrogels are beneficial to the exploitation of luteolin-based products. Moreover, some registered clinical trials on luteolin are being carried out, yet clinical research on anticancer effects should be continuously promoted.

Luteolin, a natural flavonoid, exhibits a protective effect on intestinal injury induced by soybean meal in early-weaned piglets

Soybean meal is known to be able to cause intestinal damage and dysfunction in early-weaned piglets. However, research on natural compounds that can alleviate these effects is scarce. In this study, the effect of luteolin, a natural flavonoid, on intestinal health of piglets fed on a soybean meal-based diet was explored. A total of eighteen 21-d-old piglets were selected and randomly divided into 3 groups: a negative control group fed with an animal protein-based diet, a positive control group fed with a soybean meal-based diet, and a luteolin group that was fed with the positive control diet supplemented with luteolin. The results suggested that luteolin supplementation significantly increased the average daily gain and average daily feed intake of early-weaned piglets, while effectively reducing the diarrhea incidence. Additionally, luteolin supplementation lowered the levels of soybean antigen-specific immunoglobulin G and immunoglobulin E anitbodies, increased the superoxide dismutase activity in both sera and small intestine mucosa, and enhanced the total antioxidant capacity in sera. Further research found that luteolin supplementation increased the intestinal villi height and decreased the crypt depth, resulting in an increased ratio of villi to crypts. At the same time, it reduced the concentration of serum diamine oxidase, improving intestinal barrier function. Moreover, luteolin significantly decreased the gene expression of Bax and Caspase-3, reducing cell apoptosis in the intestinal mucosa. Luteolin supplementation also increased the abundance of Actinobacteria at the phylum level, reduced the abundance of Prevotella and increased the abundance of Olsenella at the genus level. In conclusion, the supplementation of luteolin to the soybean meal diet was capable of effectively reducing allergic response, enhancing the antioxidant capacity of early-weaned piglets, protecting their intestinal barrier function, inhibiting intestinal mucosal cell apoptosis, and altering the intestinal microbiota structure, therefore promoting intestinal health and improving production performance in early-weaned piglets.

Luteolin Alleviates Oxidative Stress in Chronic Obstructive Pulmonary Disease Induced by Cigarette Smoke via Modulation of the TRPV1 and CYP2A13/NRF2 Signaling Pathways

The current study aims to investigate the therapeutic potential of luteolin (Lut), a naturally occurring flavonoid found in various medicinal plants, for treating chronic obstructive pulmonary disease (COPD) through both in vitro and in vivo studies. The results demonstrated that Lut increased body weight, reduced lung tissue swelling and lung damage indices, mitigated systemic oxidative stress levels, and decreased alveolar fusion in cigarette smoke (CS)- and lipopolysaccharide (LPS)-induced COPD mice. Additionally, Lut was observed to downregulate the expression of the TRPV1 and CYP2A13 proteins while upregulating SIRT6 and NRF2 protein expression in CS + LPS-induced COPD mice and cigarette smoke extract (CSE)-treated A549 cells. The concentrations of total reactive oxygen species (ROS) and mitochondrial ROS in A549 cells induced by CSE significantly increased. Moreover, CSE caused a notable elevation of intracellular Ca2+ levels in A549 cells. Importantly, Lut exhibited inhibitory effects on the inward flow of Ca2+ and attenuated the overproduction of mitochondrial and intracellular ROS in A549 cells treated with CSE. In conclusion, Lut demonstrated a protective role in alleviating oxidative stress and inflammation in CS + LPS-induced COPD mice and CSE-treated A549 cells by regulating TRPV1/SIRT6 and CYP2A13/NRF2 signaling pathways.

Inflammation and cardiometabolic diseases induced by persistent organic pollutants and nutritional interventions: Effects of multi-organ interactions

The development and outcome of inflammatory diseases are associated with genetic and lifestyle factors, which include chemical and nonchemical stressors. Persistent organic pollutants (POPs) are major groups of chemical stressors. For example, dioxin-like polychlorinated biphenyls (PCBs), per- and polyfluoroalkyl substances (PFASs), and polybrominated diphenyl ethers (PBDEs) are closely associated with the incidence of inflammatory diseases. The pathology of environmental chemical-mediated inflammatory diseases is complex and may involve disturbances in multiple organs, including the gut, liver, brain, vascular tissues, and immune systems. Recent studies suggested that diet-derived nutrients (e.g., phytochemicals, vitamins, unsaturated fatty acids, dietary fibers) could modulate environmental insults and affect disease development, progression, and outcome. In this article, mechanisms of environmental pollutant-induced inflammation and cardiometabolic diseases are reviewed, focusing on multi-organ interplays and highlighting recent advances in nutritional strategies to improve the outcome of cardiometabolic diseases associated with environmental exposures. In addition, advanced system biology approaches are discussed, which present unique opportunities to unveil the complex interactions among multiple organs and to fuel the development of precision intervention strategies in exposed individuals.

Multi-Omics Analysis to Understand the Effects of Dietary Proanthocyanidins on Antioxidant Capacity, Muscle Nutrients, Lipid Metabolism, and Intestinal Microbiota in Cyprinus carpio

Proanthocyanidins (Pros), a natural polyphenolic compound found in grape seed and other plants, have received significant attention as additives in animal feed. However, the specific mechanism by which Pros affect fish health remains unclear. Therefore, the aim of this study was to investigate the potential effects of dietary Pro on common carp by evaluating biochemical parameters and multi-omics analysis. The results showed that Pro supplementation improved antioxidant capacity and the contents of polyunsaturated fatty acids (n-3 and n-6) and several bioactive compounds. Transcriptomic analysis demonstrated that dietary Pro caused an upregulation of the sphingolipid catabolic process and the lysosome pathway, while simultaneously downregulating intestinal cholesterol absorption and the PPAR signaling pathway in the intestines. Compared to the normal control (NC) group, the Pro group exhibited higher diversity in intestinal microbiota and an increased relative abundance of Cetobacterium and Pirellula. Furthermore, the Pro group had a lower Firmicutes/Bacteroidetes ratio and a decreased relative abundance of potentially pathogenic bacteria. Collectively, dietary Pro improved antioxidant ability, muscle nutrients, and the diversity and composition of intestinal microbiota. The regulation of lipid metabolism and improvement in muscle nutrients were linked with changes in the intestinal microbiota.

Fabrication of Luteolin Loaded Zein-Caseinate Nanoparticles and its Bioavailability Enhancement in Rats

Luteolin loaded zein nanoparticles (Lut-ZNP) were prepared by using sodium caseinate as an electrostatic stabilizer. The formulation of the nanoparticles was optimized. Lut-ZNP were spray-dried, and the physicochemical properties were characterized by SEM, XRD, FT-IR and DSC. Then, the bioavailability of luteolin in rats was determined. Under the formulation of luteolin, zein and sodium caseinate with mass ratio of 1:5:15, the particle size, ζ-potential, encapsulation efficiency and loading efficiency of Lut-ZNP were 171.8 nm, -49.05 mV, 85.85% and 3.15%, respectively. Luteolin existed in the nanoparticles with amorphous form. Lut-ZNP exhibited good redispersibility in water after drying. Compared with free luteolin, the solubility, stability and release of luteolin in Lut-ZNP were greatly improved. Besides, the fecal excretion of luteolin in rats was significantly reduced after oral administration of Lut-ZNP. In addition to native luteolin, its metabolites including sulfate, glucuronidate and methylated glucuronidate were found in rat plasma. Lut-ZNP significantly increased the plasma concentrations of luteolin and its metabolites, and the bioavailability of luteolin was enhanced by 2.92 times.

Anticancer effect of novel luteolin capped gold nanoparticles selectively cytotoxic towards human cervical adenocarcinoma HeLa cells: An in vitro approach

BACKGROUND

Although luteolin has been confirmed as potent anticancer agent, its potential application as therapeutic is limited by its water solubility. To overcome this shortcoming nanoparticle technology approach was applied. Owing to their proven low toxicity and the possibility to be easily functionalized gold nanoparticles (AuNP) were the nanosystem of choice used in this study. Novel luteolin capped gold nanoparticles (AuNPL) were synthesized and their anticancer effect towards human cervical adenocarcinoma HeLa cells was investigated in vitro.

METHODS

AuNPL were synthesized by reducing chloroauric acid by trisodium citrate with subsequent addition of luteoline during synthesis and their physicochemical characterization was done. AuNPL cytotoxicity against HeLa, human malignant melanoma A375, and normal human keratinocytes HaCaT cells was tested by MTT cell survival assay, and their IC50 values were determined. The capability of AuNPL to induce cell cycle arrest and apoptosis in HeLa cells were demonstrated by flow cytometry. The antioxidant activity of AuNPL was assessed by DPPH· and ABTS·+ scavenging assays. Cytoprotective properties of AuNPL towards HaCaT cells were examined by measuring the physiological and H2O2 induced intracellular reactive oxygen species (ROS) levels using flow cytometry. Also, genotoxicity of AuNPL in HaCaT cells was investigated by the single cell alkaline comet assay.

RESULTS

Spherical AuNPL, stable in aqueous solution up to six months at 4 °C were obtained in the synthesis. The selectivity in the cytotoxic action of AuNPL on HeLa and A375 cancer cells compared with their cytotoxicity on normal keratinocytes HaCaT was observed. AuNPL exerted their cytotoxic activity against HeLa cells through accumulation of the cells in the subG1 phase of the cell cycle, inducing the apoptotic cell death mediated by the activation of caspase-3 - 8, and - 9. AuNPL antioxidative potential was confirmed by DPPH· and ABTS·+ scavenging assays. IC50 concentration of AuNPL exerted cytoprotective effect against HaCaT cells by the significant reduction of the physiological intracellular ROS level. Additionally, AuNPL were shown as more cytoprotective towards HaCaT cells then luteolin due to the more successful elimination of H2O2 induced intracellular ROS. Moreover, nontoxic concentrations of AuNPL did not cause considerable DNA damage of HaCaT cells, indicating low genotoxicity of the nanoparticles.

CONCLUSION

Synthesized AuNPL showed selective cytotoxic activity against HeLa cells, while being nontoxic and cytoprotective against HaCaT cells. The observed findings encourage further investigation of AuNPL as a promising novel anticancer agent.

Therapeutic considerations of bioactive compounds in Alzheimer's disease and Parkinson's disease: Dissecting the molecular pathways

Leading neurodegenerative diseases Alzheimer's disease (AD) and Parkinson's disease (PD) are characterized by the impairment of memory and motor functions, respectively. Despite several breakthroughs, there exists a lack of disease-modifying treatment strategies for these diseases, as the available drugs provide symptomatic relief and bring along side effects. Bioactive compounds are reported to bear neuroprotective properties with minimal toxicity, however, a detailed elucidation of their modes of neuroprotection is lacking. The review elucidates the neuroprotective mechanism(s) of some of the major phyto-compounds in pre-clinical and clinical studies of AD and PD to understand their potential in combating these diseases. Curcumin, eugenol, resveratrol, baicalein, sesamol and so on have proved efficient in countering the pathological hallmarks of AD and PD. Curcumin, resveratrol, caffeine and so on have reached the clinical phases of these diseases, while aromadendrin, delphinidin, cyanidin and xanthohumol are yet to be extensively explored in pre-clinical phases. The review highlights the need for extensive investigation of these compounds in the clinical stages of these diseases so as to utilize their disease-modifying abilities in the real field of treatment. Moreover, poor pharmacokinetic properties of natural compounds are constraints to their therapeutic yields and this review suggests a plausible contribution of nanotechnology in overcoming these limitations.

The Effect of Sodium Benzoate on Host Health: Insight into Physiological Indexes and Gut Microbiota

Sodium benzoate (SB) is a common food preservative widely used in the food industry. However, the effects of SB intake on host health at different stages were still unclear. Hence, we investigated the impact of SB with three concentrations (150 mg/kg, 500 mg/kg and 1000 mg/kg) and at three stages (intake for 5-weeks, intake for 10-weeks and removal for 5 weeks) on host health in normal mice. The results showed that SB intake for 5 weeks slightly changed gut microbiota composition, but it significantly increased TG (only 150 mg/kg and 1000 mg/kg) and blood glucose levels (only 500 mg/kg) and promoted the secretion of interleukin (IL)-1β and IL-6 (p < 0.01). However, SB intake for 10 weeks mostly maintained normal glucolipid metabolism; although, IL-1β (p < 0.01) and IL-6 (p < 0.05) levels were also significantly increased and positively regulated the gut microbiota by significantly increasing the relative abundance of Lactobacillus and significantly decreasing the relative abundance of Ileibacterium. Meanwhile, the safety of SB for host metabolism and gut microbiota was also confirmed via a fecal microbiota transplantation experiment. In addition, we found that SB removal after 10 weeks of intake significantly increased the levels of blood glucose, insulin and HOMA-IR index, which might be attributed to gut microbiota dysbiosis. Mechanistically, these positive effects and negative effects had no close relationship with the concentration of short-chain fatty acids in the gut, which might be associated with metabolites of SB or special bacterial strains. In short, this work provided positive evidence for the safety of SB consumption within the recommended range.

Application of Luteolin in Neoplasms and Nonneoplastic Diseases

Researchers are amazed at the multitude of biological effects of 3',4',5,7-tetrahydroxyflavone, more commonly known as luteolin, as it simultaneously has antioxidant and pro-oxidant, as well as antimicrobial, anti-inflammatory, and cancer-preventive, properties. The anticancer properties of luteolin constitute a mosaic of pathways due to which this flavonoid influences cancer cells. Not only is it able to induce apoptosis and inhibit cancer cell proliferation, but it also suppresses angiogenesis and metastasis. Moreover, luteolin succeeds in cancer cell sensitization to therapeutically induced cytotoxicity. Nevertheless, apart from its promising role in chemoprevention, luteolin exhibits numerous potential utilizations in patients with conditions other than neoplasms, which include inflammatory skin diseases, diabetes mellitus, and COVID-19. This review aims to present the multidimensionality of the luteolin's impact on both neoplastic and nonneoplastic diseases. When it comes to neoplasms, we intend to describe the complexity of the molecular mechanisms that underlay luteolin's anticancer effectiveness, as well as to prove the usefulness of integrating this flavonoid in cancer therapy via the analysis of recent research on breast, colon, and lung cancer. Regarding nonneoplastic diseases, this review aims to emphasize the importance of researching the potential of luteolin in areas such as diabetology, virology, and dermatology as it summarizes the most important discoveries in those fields regarding its application.

Enantioselective effects of paclobutrazol and its enantiomers on glycolipid metabolism in zebrafish (Danio rerio)

Paclobutrazol is a plant growth inhibitor widely used in agricultural production. However, toxicology studies of paclobutrazol enantiomers towards aquatic organisms are limited. Herein, effects of paclobutrazol and its two enantiomers (2R, 3R; 2S, 3S) on glycolipid metabolism of zebrafish have been systemically explored at the concentration of 10 mg/L through biochemical analyses, LC-MS/MS, molecular dynamics simulation, and gene expression. In all treatments, the contents of glucose, citric acid and lactate significantly were increased while the glycogen and pyruvate contents were decreased, in which (2R, 3R)-paclobutrazol exhibited a greater effect than the (2S, 3S)-enantiomer (P < 0.05). Then, activities of hexokinase and lactate dehydrogenase in (2R, 3R)-paclobutrazol treatment were 0.74- and 1.18-fold higher than (2S, 3S)-enantiomer treatment, respectively (P < 0.001), and the results of molecular dynamics simulation revealed that the binding free energy of hexokinase 1 to (2R, 3R)-paclobutrazol was higher than that to the antipode. Moreover, lipids including triglycerides, total cholesterol, fatty acids, bile acids and glycerophospholipids in zebrafish were strikingly affected after paclobutrazol exposure. The (2R, 3R)-paclobutrazol-treated group showed the most obvious changes, indicating that it possessed much stronger disruption ability on the lipid metabolism of zebrafish. Furthermore, qRT-PCR analysis results revealed that (2R, 3R)-enantiomer significantly impacted expressions of glycolipid metabolism-related genes (hk1, g6pc, pck1, pk, aco, cebpa, cyp51, fasn and ppara) in zebrafish than (2S, 3S)-enantiomer (P < 0.05). Briefly, this study provides new evidences for the toxicity of paclobutrazol to aquatic organisms and the potential risk to human health at the chiral level.

Luteolin Mitigates Diabetic Dyslipidemia in Rats by Modulating ACAT-2, PPARα, SREBP-2 Proteins, and Oxidative Stress

Diabetic dyslipidemia is a crucial link between type-2 diabetes mellitus (T2DM) and atherosclerotic cardiovascular diseases (ASCVD). Natural biologically active substances have been advocated as complementary remedies for ASCVD and T2DM. Luteolin, a flavonoid, exhibits antioxidant, hypolipidemic, and antiatherogenic effects. Hence, we aimed to determine influence of luteolin on lipid homeostasis and hepatic damage in rats with T2DM induced by high-fat-diet (HFD) and streptozotocin (STZ). After being fed HFD for 10 days, male Wistar rats received 40 mg/kg STZ intraperitoneal injection on 11th day. Seventy-two hours later, hyperglycemic rats (fasting glucose > 200 mg/dL) were randomized into groups, and oral hydroxy-propyl-cellulose, atorvastatin (5 mg/kg), or luteolin (50 mg/kg or 100 mg/kg) administered daily, while continuing HFD for 28 days. Luteolin significantly ameliorated dyslipidemia levels and concomitantly improved atherogenic index of plasma in a dose-dependent manner. Increased levels of malondialdehyde and diminished levels of superoxide dismutase, catalase, and glutathione in HFD-STZ-diabetic rats were significantly regulated by luteolin. Luteolin significantly intensified PPARα expression while decreasing expression of acyl-coenzyme A:cholesterol acyltransferase-2 (ACAT-2) and sterol regulatory element binding protein-2 (SREBP-2) proteins. Moreover, luteolin effectively alleviated hepatic impairment in HFD-STZ-diabetic rats to near-normal control levels. The findings of the present study expound mechanisms by which luteolin mitigated diabetic dyslipidemia and alleviated hepatic impairment in HFD-STZ-diabetic rats by amelioration of oxidative stress, modulation of PPARα expression, and downregulation of ACAT-2 and SREBP-2. In conclusion, our results imply that luteolin may be efficacious in management of dyslipidemia in T2DM, and future research may be essential to substantiate our findings.

Targeting calcium regulators as therapy for heart failure: focus on the sarcoplasmic reticulum Ca-ATPase pump

Impaired myocardial Ca2+ cycling is a critical contributor to the development of heart failure (HF), causing changes in the contractile function and structure remodeling of the heart. Within cardiomyocytes, the regulation of sarcoplasmic reticulum (SR) Ca2+ storage and release is largely dependent on Ca2+ handling proteins, such as the SR Ca2+ ATPase (SERCA2a) pump. During the relaxation phase of the cardiac cycle (diastole), SERCA2a plays a critical role in transporting cytosolic Ca2+ back to the SR, which helps to restore both cytosolic Ca2+ levels to their resting state and SR Ca2+ content for the next contraction. However, decreased SERCA2a expression and/or pump activity are key features in HF. As a result, there is a growing interest in developing therapeutic approaches to target SERCA2a. This review provides an overview of the regulatory mechanisms of the SERCA2a pump and explores potential strategies for SERCA2a-targeted therapy, which are being investigated in both preclinical and clinical studies.

Mitigation of Insulin Resistance by Natural Products from a New Class of Molecules, Membrane-Active Immunomodulators

Insulin resistance (IR), accompanied by an impaired cellular glucose uptake, characterizes diverse pathologies that include, but are not limited to, metabolic disease, prediabetes and type 2 diabetes. Chronic inflammation associated with deranged cellular signaling is thought to contribute to IR. The key molecular players in IR are plasma membrane proteins, including the insulin receptor and glucose transporter 4. Certain natural products, such as lipids, phenols, terpenes, antibiotics and alkaloids have beneficial effects on IR, yet their mode of action remains obscured. We hypothesized that these products belong to a novel class of bioactive molecules that we have named membrane-active immunomodulators (MAIMs). A representative MAIM, the naturally occurring medium chain fatty acid ester diethyl azelate (DEA), has been shown to increase the fluidity of cell plasma membranes with subsequent downstream effects on cellular signaling. DEA has also been shown to improve markers of IR, including blood glucose, insulin and lipid levels, in humans. The literature supports the notion that DEA and other natural MAIMs share similar mechanisms of action in improving IR. These findings shed a new light on the mechanism of IR mitigation using natural products, and may facilitate the discovery of other compounds with similar activities.

Flavonoids improve type 2 diabetes mellitus and its complications: a review

The prevalence of type 2 diabetes mellitus (T2DM) is increasing every year. Medications are currently the most common therapy for T2DM. However, these medications have certain adverse effects. In order to find safe and effective ways to improve this disease, researchers have discovered that some natural products can decrease blood sugar. Flavonoids are one of the most essential low molecular weight phenolic chemicals in the plant world, which widely exist in plant roots, stems, leaves, flowers, and fruits. They possess a variety of biological activities, including organ protection, hypoglycemic, lipid-lowering, anti-oxidative and anti-inflammatory effects. Some natural flavonoids ameliorate T2DM and its complications through anti-oxidation, anti-inflammatory action, glucose and lipid metabolism regulation, insulin resistance management, etc. Hence, this review aims at demonstrating the potential benefits of flavonoids in T2DM and its complications. This laid the foundation for the development of novel hypoglycemic medications from flavonoids.

Protective Effects of Naringenin and Apigenin in Ameliorating Skin Damage via Mediating the Nrf2 and NF-κB Pathways in Mice

Naringenin and apigenin are common flavonoids derived from edible plants with the potential to alleviate inflammation and improve skin antioxidation. This study aimed to evaluate the effects of naringenin and apigenin on oleic acid-induced skin damage in mice and compare their underlying mechanisms of action. Triglycerides and non-esterified fatty acids were significantly decreased by naringenin and apigenin, while apigenin intervention resulted in a better recovery of skin lesions. Naringenin and apigenin improved the antioxidative abilities of the skin by increasing catalase and total antioxidant capacity levels and decreasing malondialdehyde and lipid peroxide levels. The release of skin proinflammatory cytokines, such as interleukin (IL)-6, IL-1β, and tumor necrosis factor α, was inhibited after naringenin and apigenin pretreatments, but naringenin only promoted the excretion of IL-10. Additionally, naringenin and apigenin regulated antioxidant defense and inflammatory response by activating nuclear factor erythroid-2 related factor 2-dependent mechanisms and suppressing the expression of nuclear factor-kappa B. In summary, naringenin and apigenin are prospective ingredients that contribute to the amelioration of skin damage by activating anti-inflammatory and antioxidative responses.

The Role of Natural Flavonoids as Telomerase Inhibitors in Suppressing Cancer Growth

Cancer is a complex and multifaceted group of diseases characterized by the uncontrolled growth and spread of abnormal cells. While cancer can be challenging and life-altering, advances in research and development have led to the identification of new promising anti-cancer targets. Telomerase is one such target that is overexpressed in almost all cancer cells and plays a critical role in maintaining telomere length, which is essential for cell proliferation and survival. Inhibiting telomerase activity can lead to telomere shortening and eventual cell death, thus presenting itself as a potential target for cancer therapy. Naturally occurring flavonoids are a class of compounds that have already been shown to possess different biological properties, including the anti-cancer property. They are present in various everyday food sources and richly present in fruits, nuts, soybeans, vegetables, tea, wine, and berries, to name a few. Thus, these flavonoids could inhibit or deactivate telomerase expression in cancer cells by different mechanisms, which include inhibiting the expression of hTERT, mRNA, protein, and nuclear translocation, inhibiting the binding of transcription factors to hTERT promoters, and even telomere shortening. Numerous cell line studies and in vivo experiments have supported this hypothesis, and this development could serve as a vital and innovative therapeutic option for cancer. In this light, we aim to elucidate the role of telomerase as a potential anti-cancer target. Subsequently, we have illustrated that how commonly found natural flavonoids demonstrate their anti-cancer activity via telomerase inactivation in different cancer types, thus proving the potential of these naturally occurring flavonoids as useful therapeutic agents.

Luteolin intake is negatively associated with all-cause and cardiac mortality among patients with type 2 diabetes mellitus

BACKGROUND

Luteolin, a common flavonoid in our daily diet, has potent anti-diabetic effects. However, its prognostic impact on type 2 diabetes mellitus (T2DM) is still uncertain. This study aimed to clarify this association.

METHODS

In this prospective cohort study, 2,461 patients with T2DM were included from the National Health and Nutrition Examination Survey. Dietary luteolin intake was estimated by the type and amount of food consumed in a 24-hour dietary recall. All-cause and cardiac mortality were ascertained by National Death Index Mortality data (as of December 31, 2019). The association of luteolin intake with mortality risk was estimated by Cox proportional hazards model.

RESULTS

The median (interquartile range) luteolin intake was 0.355 (0.130, 0.835) mg/day. During the follow-up (median, 8.4 years), 561 all-cause deaths (including 136 cardiac deaths) were documented. Per-unit increment of luteolin intake (natural logarithm transformed) was found to reduce all-cause mortality by 7.0% (P = 0.024) and cardiac mortality by 22.6% (P = 0.001) in patients with T2DM. An inverse dose-response association was identified between luteolin intake (range: 0.005-9.870 mg/day) and mortality risk. The consistent result was also shown when stratified by age, gender, race, body mass index, HbA1c level, and T2DM duration. Moreover, luteolin intake increment was also shown to be associated with a lower C-reactive protein level at baseline (β =-0.332; 95% CI =-0.541, -0.122).

CONCLUSION

The current study confirmed that the dietary luteolin intake increment reduced all-cause mortality (especially cardiac mortality) in patients with T2DM, which may be attributed to the anti-inflammatory property of luteolin.

Applications of Perilla frutescens Extracts in Clinical Practice

(1) Background: Perilla frutescens (L.) Britt. is an important pharmaceutical crop that remains a focus point for researchers worldwide due to its complex phytochemical constituents, medicinal effects, and nutraceutical properties. The literature data are based on animal and cell culture studies, so the clinical evidence for the therapeutic effects is poorly outlined. The aim of this review was to provide an updated and thorough understanding of Perilla frutescens applications in clinical practice using data derived from human studies, and to outline the potential directions and perspectives for further studies on this crop. (2) Methods: Medline, Embase, and Cochrane databases were used to find relevant studies. All interventional studies that evaluated the effect of Perilla frutescens in human subjects were assessed. (3) Results: The main perspectives that can be contoured from the presented literature evaluation are an important clinical effect of Perilla frutescens extracts on allergic rhinoconjuctivitis, especially in young populations, a potent hypolipemiant effect that, in conjunction with increased serum biological antioxidant potential, determines significant improvements in cognitive function and a wide variety of miscellaneous clinical effects that need further exploration. (4) Conclusions: Supplementary research is needed in order to demonstrate the therapeutic effects of Perilla frutescens in controlled clinical settings.

Induction, Flavonoids Contents, and Bioactivities Analysis of Hairy Roots and True Roots of Tetrastigma hemsleyanum Diels et Gilg

The flavonoids in Tetrastigma hemsleyanum Diels et Gilg (T. hemsleyanum) have high medicinal value. However, because of slow growth and harsh ecological environments, T. hemsleyanum is currently an endangered species. In light of this, we present a detailed hairy root induction procedure as a promising alternative to true roots with medicinal value. The percentage of explants induced by Agrobacterium rhizogenes (A. rhizogenes) to produce hairy roots out of the total number of explants infected (induction rate 1) was 95.83 ± 7.22%, and the proportion of hairy roots that contained Rol B fragments among all the hairy roots with or without Rol B fragments (positive rate) was 96.57 ± 1.72%. The transformation was further confirmed by the expression of the GUS protein. A high-productive hairy root line was screened for the comparative profiling of six flavonoids with true roots using high-performance liquid chromatography (HPLC). The contents of (+)-catechin, (−)-epicatechin, neochlorogenic acid, luteolin-6-C-glucoside, and orientin were 692.63 ± 127.24, 163.34 ± 31.86, 45.95 ± 3.46, 209.68 ± 6.03, and 56.82 ± 4.75 μg/g dry weight (DW) of 30-day-old hairy roots, respectively, which were higher than those of 3-year-old true roots. Hairy roots have stronger antioxidant activity than true roots. Overall, the hairy roots of T. hemsleyanum could serve as promising alternative sources for the production of flavonoids with medicinal uses.

Flavonoids attenuate cancer metabolism by modulating Lipid metabolism, amino acids, ketone bodies and redox state mediated by Nrf2

Metabolic reprogramming of cancer cells is a common hallmark of malignant transformation. The preference for aerobic glycolysis over oxidative phosphorylation in tumors is a well-studied phenomenon known as the Warburg effect. Importantly, metabolic transformation of cancer cells also involves alterations in signaling cascades contributing to lipid metabolism, amino acid flux and synthesis, and utilization of ketone bodies. Also, redox regulation interacts with metabolic reprogramming during malignant transformation. Flavonoids, widely distributed phytochemicals in plants, exert various beneficial effects on human health through modulating molecular cascades altered in the pathological cancer phenotype. Recent evidence has identified numerous flavonoids as modulators of critical components of cancer metabolism and associated pathways interacting with metabolic cascades such as redox balance. Flavonoids affect lipid metabolism by regulating fatty acid synthase, redox balance by modulating nuclear factor-erythroid factor 2-related factor 2 (Nrf2) activity, or amino acid flux and synthesis by phosphoglycerate mutase 1. Here, we discuss recent preclinical evidence evaluating the impact of flavonoids on cancer metabolism, focusing on lipid and amino acid metabolic cascades, redox balance, and ketone bodies.

Luteolin protects against adipogenic and lipogenic potency induced by human relevant mixtures of persistent organic pollutants (POPs) in the 3T3-L1 model

Human exposure to persistent organic pollutants (POPs) may contribute to obesogenic effects. We have previously shown that POP mixtures modelled on blood levels relevant to the Scandinavian population induces adipogenic effects in the mouse 3T3-L1 cell line. Luteolin is a flavone that has shown anti-lipogenic and anti-adipogenic effects on adipogenesis in in vitro models. In this study, luteolin has been applied to inhibit adipocyte formation and intracellular lipid content increase induced by a human relevant mixture of POPs. 3T3-L1 cells were exposed to a POP mixture consisting of 29 chemicals, including amongst others polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), perfluoroalkylated acids (PFAAs), and polybrominated diphenyl ethers (PBDEs). Rosiglitazone was applied as a positive lipogenic control. Luteolin was tested between 0.5 and 10 μM. High content analysis was used to assess changes in adipocyte formation and intracellular lipid content in the 3T3-L1 cell line. Luteolin significantly reduced POP-induced adipocyte formation at 2, 5 and 10 μM, and lipid accumulation at 10 μM. Interestingly, luteolin did not affect rosiglitazone induced adipo- and lipogenic effects, suggesting differences in mechanisms of action. In conclusion, this in vitro study shows that dietary polyphenols such as luteolin may protect against POP induced adipo- and lipogenic effects.

Targeting epigenetics in diabetic cardiomyopathy: Therapeutic potential of flavonoids

The pathophysiological mechanisms of diabetic cardiomyopathy have been extensively studied, but there is still a lack of effective prevention and treatment methods. The ability of flavonoids to protect the heart from diabetic cardiomyopathy has been extensively described. In recent years, epigenetics has received increasing attention from scholars in exploring the etiology and treatment of diabetes and its complications. DNA methylation, histone modifications and non-coding RNAs play key functions in the development, maintenance and progression of diabetic cardiomyopathy. Hence, prevention or reversal of the epigenetic alterations that have occurred during the development of diabetic cardiomyopathy may alleviate the personal and social burden of the disease. Flavonoids can be used as natural epigenetic modulators in alternative therapies for diabetic cardiomyopathy. In this review, we discuss the epigenetic effects of different flavonoid subtypes in diabetic cardiomyopathy and summarize the evidence from preclinical and clinical studies that already exist. However, limited research is available on the potential beneficial effects of flavonoids on the epigenetics of diabetic cardiomyopathy. In the future, clinical trials in which different flavonoids exert their antidiabetic and cardioprotective effects through various epigenetic mechanisms should be further explored.

Interaction of luteolin, naringenin, and their sulfate and glucuronide conjugates with human serum albumin, cytochrome P450 (CYP2C9, CYP2C19, and CYP3A4) enzymes and organic anion transporting polypeptide (OATP1B1 and OATP2B1) transporters

Luteolin and naringenin are flavonoids found in various foods/beverages and present in certain dietary supplements. After a high intake of these flavonoids, their sulfate and glucuronide conjugates reach micromolar concentrations in the bloodstream. Some pharmacokinetic interactions of luteolin and naringenin have been investigated in previous studies; however, only limited data are available in regard to their metabolites. In this study, we aimed to investigate the interactions of the sulfate and glucuronic acid conjugates of luteolin and naringenin with human serum albumin, cytochrome P450 (CYP2C9, 2C19, and 3A4) enzymes, and organic anion transporting polypeptide (OATP1B1 and OATP2B1) transporters. Our main findings are as follows: (1) Sulfate conjugates formed more stable complexes with albumin than the parent flavonoids. (2) Luteolin and naringenin conjugates showed no or only weak inhibitory action on the CYP enzymes examined. (3) Certain conjugates of luteolin and naringenin are potent inhibitors of OATP1B1 and/or OATP2B1 enzymes. (4) Conjugated metabolites of luteolin and naringenin may play an important role in the pharmacokinetic interactions of these flavonoids.

Recent Updates on Source, Biosynthesis, and Therapeutic Potential of Natural Flavonoid Luteolin: A Review

Nature gives immense resources that are beneficial to humankind. The natural compounds present in plants provide primary nutritional values to our diet. Apart from food, plants also provide chemical compounds with therapeutic values. The importance of these plant secondary metabolites is increasing due to more studies revealing their beneficial properties in treating and managing various diseases and their symptoms. Among them, flavonoids are crucial secondary metabolite compounds present in most plants. Of the reported 8000 flavonoid compounds, luteolin is an essential dietary compound. This review discusses the source of the essential flavonoid luteolin in various plants and its biosynthesis. Furthermore, the potential health benefits of luteolins such as anti-cancer, anti-microbial, anti-inflammatory, antioxidant, and anti-diabetic effects and their mechanisms are discussed in detail. The activity of luteolin and its derivatives are diverse, as they help to prevent and control many diseases and their life-threatening effects. This review will enhance the knowledge and recent findings regarding luteolin and its therapeutic effects, which are certainly useful in potentially utilizing this natural metabolite.