Baicalein improves the symptoms of polycystic ovary syndrome by mitigating oxidative stress and ferroptosis in the ovary and gravid placenta

BACKGROUND

Polycystic ovary syndrome is a metabolic and hormonal disorder that is closely linked to oxidative stress. Within individuals diagnosed with PCOS, changes occur in the ovaries, resulting in an excessive buildup of iron and peroxidation of lipids, both of which may be associated with the occurrence of ferroptosis. Baicalein, a flavonoid found in the roots of Scutellaria baicalensis and widely known as Chinese skullcap, is known for its anti-inflammatory and anti-ferroptotic properties, which protect against various diseases. Nevertheless, there has been no investigation into the impact of baicalein on polycystic ovary syndrome.

PURPOSE

This study aimed to correlate ferroptosis with polycystic ovary syndrome and to assess the effects of baicalein on ovarian dysfunction and placental development in pregnant patients.

STUDY DESIGN AND METHODS

Polycystic ovary syndrome was induced in a rat model through the administration of dehydroepiandrosterone, and these rats were treated with baicalein. Oxidative stress and inflammation levels were assessed in serum and ovaries, and tissue samples were collected for histological and protein analyses. Furthermore, different groups of female rats were mated with male rats to observe pregnancy outcomes and tissue samples were obtained for histological, protein, and RNA sequencing. Then, RNA sequencing of the placenta was performed to determine the key genes involved in ferroptosis negative regulation (FNR) signatures.

RESULTS

Baicalein was shown to reduce ovarian oxidative stress and pathology. Baicalein also ameliorated polycystic ovary syndrome by decreasing lipid peroxidation and chronic inflammation and modulating mitochondrial functions and ferroptosis in the ovaries. Specifically, glutathione peroxidase and ferritin heavy chain 1 were considerably downregulated in polycystic ovary syndrome gravid rats compared to their expression in the control group, and most of these differences were reversed after baicalein intervention.

CONCLUSIONS

Our findings, initially, indicated that baicalein could potentially enhance the prognosis of individuals suffering from polycystic ovary syndrome by reducing oxidative stress and ferroptosis, thus potentially influencing the formulation of a therapeutic approach to address this condition.

Baicalein inhibits biofilm formation of avian pathogenic Escherichia coli in vitro mainly by affecting adhesion

Avian pathogenic Escherichia coli (APEC) is a widespread bacterium that causes significant economic losses to the poultry industry. APEC biofilm formation may result in chronic, persistent, and recurrent infections in clinics, making treatment challenging. Baicalein is a natural product that exhibits antimicrobial and antibiofilm activities. This study investigates the inhibitory effect of baicalein on APEC biofilm formation at different stages. The minimum inhibitory concentration (MIC) of baicalein on APEC was determined, and the growth curve of APEC biofilm formation was determined. The effects of baicalein on APEC biofilm adhesion, accumulation, and maturation were observed using optical microscopy, confocal laser scanning microscopy, and scanning electron microscopy. The biofilm inhibition rate of baicalein was calculated at different stages. The MIC of baicalein against APEC was 256 μg/mL. The process of APEC biofilm maturation takes approximately 48 h after incubation, with initial adhesion completed at 12 h, and cell accumulation finished at 24 h. Baicalein had a significant inhibitory effect on APEC biofilm formation at concentrations above 1 μg/mL (p < 0.01). Notably, baicalein had the highest rate of biofilm formation inhibition when added at the adhesion stage. Therefore, it can be concluded that baicalein is a potent inhibitor of APEC biofilm formation in vitro and acts, primarily by inhibiting cell adhesion. These findings suggests that baicalein has a potential application for inhibiting APEC biofilm formation and provides a novel approach for the prevention and control APEC-related diseases.

Baicalein alleviates intrahepatic cholestasis by regulating bile acid metabolism via an FXR-dependent manner

Cholestasis is characterized by impaired bile secretion and flow, leading to the accumulation of toxic bile acids in the liver, further causing inflammatory reaction, fibrosis, and ultimately liver transplantation. Although first-line clinical agents such as Ursodeoxycholic acid (UDCA) and Obeticholic acid (OCA) are available, serious side effects still exist. Therefore, pharmacologic treatment of cholestatic liver disease remains challenging. Here, we used a murine model of cholestasis treated with or without intraperitoneal injection of baicalein and found that baicalein could attenuate 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC) diet-induced inflammatory response, ductular reaction, liver fibrosis, and bile acid metabolism disorders. Furthermore, the therapeutic effect of baicalein was hampered in the presence of Guggulsterone (GS), an Farnesoid X receptor (FXR) antagonist. These results indicated that baicalein alleviated DDC diet-induced cholestatic liver injury in an FXR-dependent manner.

Baicalein improves renal interstitial fibrosis by inhibiting the ferroptosis in vivo and in vitro

Evidence indicates that Baicalein can ameliorate renal interstitial fibrosis by inducing myofibroblast apoptosis and inhibit the RLS3-induced ferroptosis in melanocytes. However, the relationship between renal interstitial fibrosis and anti-ferroptosis affected by Baicalein remains unclear. In our study, the anti-fibrosis and anti-ferroptosis effects of Baicalein were assessed in a rat model induced by the UUO method in vivo, and the effects of Baicalein on Erastin-induced ferroptosis of renal MPC-5 cells were examined by Western blot of fibrosis-related and ferroptosis-related proteins in vitro. In the UUO-induced rat model, Baicalein decreased kidney weight loss, improved renal function assessed the biomarks of urinary albumin excretion, serum creatine, and BUN levels, and reduced renal tubular injury. Furthermore, Baicalein inhibited renal ferroptosis by reducing ROS and MDA levels and increasing SOD and GSH levels in the UUO rat model. In addition, Baicalein potently reduced the expression of fibrosis-related proteins such as TGF-β1, a-SMA, and Smad-2 to prevent renal interstitial fibrosis, and increased the expression of ferroptosis-related proteins such as SLC7A11, GPX4, and FTH to inhibit ferroptosis both in vitro and in vivo. Taken together, Baicalein exerts anti-fibrosis activity by reducing the ferroptosis response on the UUO-induced rat model and renal MPC5 cells. Therefore, Baicalein, as a novel therapeutic method on kidney diseases with strong activity in suppressing ferroptosis, could be a potential alternative treatment for renal interstitial fibrosis.

Baicalein glycymicelle ophthalmic solution: Preparation, in vitro antimicrobial activities, and antimicrobial mechanism evaluations

The purpose of this study was to develop a novel baicalein (BAI) loaded glycymicelle ophthalmic solution with small molecule phytochemical glycyrrhizin as nanocarriers and to explore this solution's potential as an antimicrobial agent against ocular infections. The optimized BAI glycymicelles had a high encapsulation efficiency (98.76 ± 1.25 %), a small particle size (54.38 ± 2.41 nm), a uniform size distribution (polydispersity index = 0.293 ± 0.083), and a zeta potential of -28.3 ± 1.17 mV. The BAI glycymicelle ophthalmic solution exhibited an excellent short-term storage stability. BAI glycymicelles significantly increased the apparent solubility and in vitro release capability of BAI. The BAI glycymicelle ophthalmic solution exhibited no hen's egg-chorioallantoic membrane' irritation and strong in vivo ocular tolerance in rabbits. The BAI glycymicelles noticeably enhanced the in vivo corneal permeation. The BAI glycymicelles also precipitated increased in vitro antioxidant activity and significantly improved in vitro antipathogen activities. Various antimicrobial mechanisms, including the destruction of the bacterial cell wall, damage to the bacterial cell membranes, interruptions to the biofilm structure, and the apoptosis of bacteria, were inflicted on BAI glycymicelles. These findings provided useful knowledge regarding the development of a novel ophthalmic solution and formulation of BAI.

Baicalein inhibits IL-1β-induced extracellular matrix degradation with decreased MCP-1 expression in primary rat chondrocytes

Baicalein is a flavonoid extracted from the roots of Scutellaria baicalensis and Scutellaria lateriflora. This compound exerts various biochemical activities, including antioxidant and anti-inflammatory effects. The study aimed to investigate the effect of baicalein on articular cartilage cells and elucidate its underlying mechanism. In primary rat chondrocyte cultures, treatment with baicalein demonstrated a reduction in the loss of proteoglycan and extracellular matrix degradation induced by interleukin (IL)-1β. Baicalein suppressed IL-1β-induced catabolic responses, including the expression and activation of matrix metalloproteinase (MMP)-13, MMP-3, and MMP-1. In addition, baicalein effectively reduced nitric oxide and prostaglandin E2 production, and it downregulated the expression of inducible nitric oxide synthase and cyclooxygenase-2 in primary rat chondrocytes. Furthermore, baicalein downregulated IL-1β-induced inflammatory chemokines and cytokines, such as GM-CSF and MCP-1. These findings suggest that baicalein could potentially mitigate the catabolic responses of IL-1β in chondrocytes, making it a promising candidate for both the prevention and treatment of osteoarthritis.

Supplementary Information

The online version contains supplementary material available at 10.1007/s43188-024-00225-4.

Endogenous crude Scutellaria baicalensis polysaccharide robustly enhances one-pot extraction and deglycosylation of baicalin

With the extensive application of baicalein in the treatment of cardiovascular and cerebrovascular diseases, its clinical and market demand has gradually expanded. But the natural yield of baicalein is very low, and it is mainly prepared by the deglycosylation of baicalin. However, the insolubility of baicalin in water significantly limits the deglycosylation of it under biocatalysis. To make biocatalysis of baicalin more efficient and environmental, a strategy was designed to enhance its water solubility through the solubilization mechanism of endogenous biological macromolecules, and the effect on the activity of glucuronidase was further explored. The results showed that wrapping with Scutellaria baicalensis polysaccharide (SBP) significantly improved the solubility of baicalin in water (the water solubility of baicalin increased by 23 times, BI/SBP = 1/12, w/w). It was not only contributed to the efficient production of baicalein by one-pot method, but also effectively improved the deglycosylation rate of baicalin (increase by 47.04 % in aqueous solution). With the help of the solubilization of endogenous polysaccharide on baicalin in aqueous solution, a green, low-cost and efficient method (one-pot method) was designed to simultaneously extract and enzymatic hydrolyze baicalin to prepare baicalein. Under the same conditions, the yield of one-pot method is 87.17 %, which was much higher than that of the conventional method (29.38 %). In addition, one-pot method with the aid of endogenous polysaccharide could simply and conveniently prepare aglycone of other insoluble natural flavonoids, which has a wide range of industrial application value.

Baicalein ameliorated obesity-induced cardiac dysfunction by regulating the mitochondrial unfolded protein response through NRF2 signaling

BACKGROUND

The mitochondrial unfolded protein response (UPRmt) is the first line of defense against mitochondrial dysfunction in several diseases. Baicalein, which is an extract of Scutellaria baicalensis Georgi roots, exerts mitoprotective effects on metabolic disorders and cardiovascular diseases. However, it remains unclear whether baicalein alleviates obesity-induced cardiac damage through the UPRmt.

PURPOSE

The present research designed to clarify the role of baicalein in lipotoxicity-induced myocardial apoptosis and investigated the UPRmt-related mechanism.

METHODS

In the in vitro experiment, palmitic acid (PA)-treated AC16 cardiomyocytes were established to mimic obesity-induced myocardial injury. After pretreatment of AC16 cells with baicalein, the levels of cell vitality, apoptosis, mitochondrial membrane potential, mitochondrial oxidative stress, and UPRmt-related proteins were determined. Additionally, AC16 cells were treated with ML385 or siRNA to explore the regulation of the UPRmt by NRF2 signaling. In the in vivo experiment, male db/db mice administered with baicalein for 8 weeks were used to validate the effects of baicalein on cardiac damage induced by obesity, the UPRmt, and the NRF2-related pathway.

RESULTS

In AC16 cardiomyocytes, PA dose-dependently increased the expression of UPRmt markers (HSP60, LONP1, ATF4, and ATF5). This increase was accompanied by enhanced production of mitochondrial ROS, reduced mitochondrial membrane potential, and elevated the expression levels of cytochrome c, cleaved caspase-3, and Bax/Bcl2, eventually leading to cell apoptosis. Baicalein treatment reversed UPRmt activation and mitochondrial damage and impeded mitochondrial-mediated cell apoptosis. Moreover, NRF2 downregulation by its inhibitor ML385 or siRNA diminished baicalein-mediated NRF2 signaling activation and UPRmt inhibition and triggered mitochondrial dysfunction. Additionally, NRF2 deficiency more intensely activated the UPRmt, resulting in mitochondrial oxidative stress and apoptosis of PA-induced cardiomyocytes, thus indicating that NRF2 plays a vital role in mitochondrial homeostasis regulation. In the in vivo study in db/db mice, baicalein inhibited the UPRmt, enhanced the antioxidant capacity, and attenuated cardiac dysfunction through a NRF2-activated pathway.

CONCLUSION

To our best knowledge, these results provide the first insight that baicalein inhibits the UPRmt to induce a protective effect against lipotoxicity-induced mitochondrial damage and cardiomyocyte apoptosis via activating NRF2 signaling and suggest a new role of NRF2 in UPRmt regulation.

Insights into dietary phytochemicals targeting Parkinson's disease key genes and pathways: A network pharmacology approach

Parkinson's disease (PD) is a complex neurological disease associated with the degeneration of dopaminergic neurons. Oxidative stress is a key player in instigating apoptosis in dopaminergic neurons. To improve the survival of neurons many dietary phytochemicals have gathered significant attention recently. Thus, the present study implements a comprehensive network pharmacology approach to unravel the mechanisms of action of dietary phytochemicals that benefit disease management. A literature search was performed to identify ligands (i.e., comprising dietary phytochemicals and Food and Drug Administration pre-approved PD drugs) in the PubMed database. Targets associated with selected ligands were extracted from the search tool for interactions of chemicals (STITCH) database. Then, the construction of a gene-gene interaction (GGI) network, analysis of hub-gene, functional and pathway enrichment, associated transcription factors, miRNAs, ligand-target interaction network, docking were performed using various bioinformatics tools together with molecular dynamics (MD) simulations. The database search resulted in 69 ligands and 144 unique targets. GGI and subsequent topological measures indicate histone acetyltransferase p300 (EP300), mitogen-activated protein kinase 1 (MAPK1) or extracellular signal-regulated kinase (ERK)2, and CREB-binding protein (CREBBP) as hub genes. Neurodegeneration, MAPK signaling, apoptosis, and zinc binding are key pathways and gene ontology terms. hsa-miR-5692a and SCNA gene-associated transcription factors interact with all the 3 hub genes. Ligand-target interaction (LTI) network analysis suggest rasagiline and baicalein as candidate ligands targeting MAPK1. Rasagiline and baicalein form stable complexes with the Y205, K330, and V173 residues of MAPK1. Computational molecular insights suggest that baicalein and rasagiline are promising preclinical candidates for PD management.

Baicalein induces apoptosis by inhibiting the glutamine-mTOR metabolic pathway in lung cancer

INTRODUCTION

Baicalein, a bioactive component of Scutellaria baicalensis Georgi, has been shown to promote apoptosis in non-small cell lung cancer cells. However, previous studies have not determined if baicalein exerts proapoptotic effects by modulating the metabolic pathways.

OBJECTIVE

To investigate if baicalein induces apoptosis in lung cancer cells by modulating the glutamine-mTOR metabolic pathway.

METHODS

The in vivo anti-lung cancer activity of baicalein (50, 100, and 200 mg/kg) was evaluated using a xenograft model. In vitro experiments were used to assess the efficacy of baicalein (for H1299: 12.5, 25, and 50 μM; for A549: 10, 20, and 40 μM) on lung cancer cell proliferation, colony formation, and apoptosis. Metabolomics analysis was performed using liquid chromatography-mass spectrometry. The binding of baicalein to glutamine transporters and glutaminase was examined using molecular docking. The overexpression of glutamine transporters was validated using qRT-PCR and western blot analyses. The levels of ASCT2, LAT1, GLS1, p-mTOR, mTOR, and apoptosis-related proteins were evaluated using western blot analysis.

RESULTS

Baicalein inhibited lung cancer xenograft tumor growth in vivo and suppressed proliferation and promoted apoptosis in lung cancer cells in vitro. Additionally, baicalein altered amino acid metabolites, especially glutamine metabolites, in H1299 and A549 cells. Mechanistically, baicalein interacted with glutamine transporters as well as glutaminase and inhibited their activation. The expression of mTOR, an apoptosis-related protein and downstream target of glutamine metabolism, was also inhibited by baicalein treatment. Importantly, we next demonstrated the suppression of mTOR signaling and the induction of apoptosis by baicalein were achieved by regulating glutamine metabolism.

CONCLUSION

Baicalein inhibited the mTOR signaling pathway and induced apoptosis by downregulating glutamine metabolism. The potential of baicalein to induce apoptosis in lung cancer cells by selectively targeting the glutamine-mTOR pathway suggests an encouraging approach for treating lung cancer.

Baicalein ameliorates cognitive impairment of vascular dementia rats via suppressing neuroinflammation and regulating intestinal microbiota

Neuroinflammation induced by chronic cerebral hypoperfusion (CCH) plays a crucial role in the pathophysiologic mechanisms of vascular dementia (VD). A growing body of research has found that intestinal microbiota is associated with a variety of central nervous system disorders and that there is a relationship between intestinal microbiota dysbiosis and cognitive dysfunction and inflammatory responses. Baicalein belongs to the class of flavonoids and has a variety of biological functions, including anti-inflammatory, antioxidant and anti-apoptotic. Baicalein has a significant improvement in memory and learning, and can be used as a potential drug for the protection and treatment of central nervous system disorders. Whether baicalein has an ameliorative effect on cognitive impairment in VD, and whether its mechanism is related to the inhibition of inflammatory response and regulation of intestinal microbiota has not been reported. We used bilateral common carotid artery occlusion (BCCAO) to establish a VD rat model. Morris water maze (MWM) test showed that baicalein improved cognitive dysfunction in VD rats. We applied HE staining, immunofluorescence and ELISA to observe that baicalein treatment significantly improved CCH-induced neuronal damage in the CA1 region of the hippocampus, and reduced glial cell activation and release of pro-inflammatory factors. Western blot showed that baicalein inhibited the activation of the TLR4/MyD88/NF-κB signaling pathway in VD rats. We applied 16 S rDNA sequencing to analyze the composition of the intestinal microbiota. The results showed that baicalein modulated the diversity and composition of the intestinal microbiota, and suppressed the relative abundance of inflammation-associated microbiota in VD rats. In conclusion, this study found that baicalein ameliorated cognitive impairment, attenuated hippocampal inflammatory responses, inhibited the TLR4/MyD88/NF-κB signaling pathway, and modulated intestinal microbiota in VD rats.

Revealing active constituents within traditional Chinese Medicine used for treating bacterial pneumonia, with emphasis on the mechanism of baicalein against multi-drug resistant Klebsiella pneumoniae

ETHNOPHARMACOLOGICAL RELEVANCE

The emergence of antibiotic-resistant bacteria has rendered it more challenging to treat bacterial pneumonia. Traditional Chinese medicine (TCM) has superior efficacy in the treatment of pneumonia, and it has the unique advantage of antibacterial resistance against multi-drug resistant (MDR) bacteria, but the medication rule and pharmacological mechanism of its antibacterial activity are not clear.

AIM OF THE STUDY

This study aims to reveal Chinese medication patterns in treating bacterial pneumonia to select bioactive constituents in core herbs, predict their pharmacological mechanisms and further explore their antibacterial ability against clinically isolated MDR Klebsiella pneumoniae (KP) and their antibacterial mechanisms.

MATERIALS AND METHODS

The high-frequency medicinal herbs to treat lung diseases were first screened from Pharmacopoeia of the People's Republic of China (ChP.), and then bioactive compounds in core herbs and targets for compounds and disease were collected. Potential targets, signaling pathways, and drugs' core components were determined by constructing protein-protein interaction network, enrichment analysis and "component-target-pathway-disease" network were mapped by Cytoscape 3.8.2, and the potential therapeutic value of selected core components was verified by comparing the disease targets in the GEO database with the herbal component targets in the ITCM database. The clinically isolated KP were screened by drug sensitivity tests with meropenem (MEM), polymyxin E (PE), and tigecycline and biofilm-forming assay; broth microdilution, chessboard methods and biofilm morphology and permeability experiments were employed to determine the antibacterial, bactericidal and biofilm inhibition ability of selected bioactive constituents alone and in combination with antibiotics; The mechanism of bioactive components on quorum sensing (QS) genes LuxS and LuxR was predicted by molecular docking and tested by RT-PCR.

RESULTS

The 13 core Chinese medicines were obtained by mining ChP., and 615 potential targets of core herbal medicine were screened, and the PI3K-Akt signaling pathway might play crucial roles in the therapeutic process. In-vitro experiments revealed that the selected core compounds, including forsythoside B, baicalin, baicalein, and forsythin, all have antibacterial activity, in which baicalein had the strongest ability and a synergistic effect in combination with MEM or PE. Their synergy exhibited a stronger effect on biofilms of MDR KP, inhibiting biofilm formation, disrupting formed biofilms, and removing the residual structures of dead bacteria. Baicalein was predicted to have stable binding capacity to LuxS and LuxR genes by molecular docking, and RT-PCR results verified that the combination of baicalein with MEM or PE was effective in inhibiting the expression of QS genes (LuxS and LuxR) and consequently suppressing biofilm formation.

CONCLUSION

The core Chinese herbal medicine in the ChP. to treat lung diseases has a multi-component, multi-target, and multi-pathway synergy to improve bacterial pneumonia. Experimental studies have confirmed that the bioactive compound baicalein was able to combat MDR KP alone and synergistic with MEM or PE, inhibited and disrupted biofilms via regulating LuxS and LuxR genes, and further disturbed quorum sensing system to promote the therapeutic efficacy, which provides a new pathway and rationale for treating MDR KP-induced bacterial pneumonia.

Moderating AKT signaling with baicalein protects against weight loss by preventing muscle atrophy in a cachexia model caused by CT26 colon cancer

Cancer cachexia is a type of energy-wasting syndrome characterized by fatigue, anorexia, muscle weakness, fat loss, and systemic inflammation. Baicalein, a flavonoid with bioactive properties, has demonstrated the ability to mitigate cardiac and skeletal muscle atrophy in different experimental settings. This effect is achieved through the inhibition of muscle proteolysis, suggesting its potential in preserving skeletal muscle homeostasis. In this study, we investigated the anti-cancer cachexia effects of baicalein in the regulation of muscle and fat wasting, both in vivo and in vitro. Baicalein attenuated body weight loss, including skeletal muscle and white adipose tissue (WAT), in CT26-induced cachectic mice. Moreover, baicalein increased muscle fiber thickness and suppressed the muscle-specific ubiquitin-protease system, including F-box only protein 32 and muscle RING-finger protein-1, by activating AKT phosphorylation both in vivo and in vitro. The use of LY294002, a particular inhibitor of AKT, eliminated the observed impact of baicalein on the improvement of muscle atrophy. In conclusion, baicalein inhibits muscle proteolysis and enhances AKT phosphorylation, indicating its potential role in cancer cachexia-associated muscle atrophy.

Restoring functional TDP-43 oligomers in ALS and laminopathic cellular models through baicalein-induced reconfiguration of TDP-43 aggregates

A group of misfolded prone-to-aggregate domains in disease-causing proteins has recently been shown to adopt unique conformations that play a role in fundamental biological processes. These processes include the formation of membrane-less sub-organelles, alternative splicing, and gene activation and silencing. The cellular responses are regulated by the conformational switching of prone-to-aggregate domains, independently of changes in RNA or protein expression levels. Given this, targeting the misfolded states of disease-causing proteins to redirect them towards their physiological conformations is emerging as an effective therapeutic strategy for diseases caused by protein misfolding. In our study, we successfully identified baicalein as a potent structure-correcting agent. Our findings demonstrate that baicalein can reconfigure existing TDP-43 aggregates into an oligomeric state both in vitro and in disease cells. This transformation effectively restores the bioactivity of misfolded TDP-43 proteins in cellular models of ALS and premature aging in progeria. Impressively, in progeria cells where defective lamin A interferes with TDP-43-mediated exon skipping, the formation of pathological TDP-43 aggregates is promoted. Baicalein, however, restores the functionality of TDP-43 and mitigates nuclear shape defects in these laminopathic cells. This establishes a connection between lamin A and TDP-43 in the context of aging. Our findings suggest that targeting physiological TDP-43 oligomers could offer a promising therapeutic avenue for treating aging-associated disorders.

Baicalein improves Na2SeO3 induced cataract by enhancing the antioxidant capacity of juvenile Sprague Dawley Rat

ETHNOPHARMACOLOGICAL RELEVANCE

Baicalein (BAI) is the crucial flavonoid component in Scutellaria baicalensis Georgi, possessing biological functions such as anti-oxidant, anti-apoptotic, and anti-inflammatory. However, there is limited intensive pharmacological and mechanistic research on the therapeutic effects of BAI for cataract treatment.

AIM OF THE STUDY

This study aimed to investigate the effects and mechanisms of BAI on Na2SeO3-induced cataract in juvenile rats.

MATERIALS AND METHODS

The cataract model was established by a single subcutaneous injection of 3.46 mg/kg Na2SeO3 on the back of 10-day-old rats. The BAI (25 mg/kg, 50 mg/kg, 100 mg/kg) was administered to the 8-day-old rats and continued until they reached 30 days of age, and the opacity of the lens was observed using a slit lamp microscope every 3 days. Pathological changes in the lens were observed using hematoxylin-eosin (HE) staining to investigate the effects of BAI on Na2SeO3-induced cataract in rats. The levels of antioxidant substances in rat serum and the lens, as well as the levels of soluble and insoluble proteins in rat lens, were measured by the reagent kit. Furthermore, the mechanism of BAI on Na2SeO3-induced cataract rats was analyzed by network pharmacology, molecular docking, and Western blot.

RESULTS

BAI significantly increased the content of soluble proteins in the lens, mitigated the dense opacity of rat lens and reduced the damage to lens epithelial cells, reduced the levels of malondialdehyde (MDA) in rat serum and lens, increased the levels of total superoxide dismutase (T-SOD) and Glutathione peroxidase (GSH-PX). The improvement effects of BAI on Na2SeO3-induced cataract may related to the mitogen-activated protein kinase (MAPK) and the phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT) signaling pathways.

CONCLUSION

In conclusion, this study demonstrated that BAI could mitigate the dense opacity of rat lens in Na2SeO3-induced cataract rats, which may be achieved through the MAPK signaling pathway and the PI3K/AKT signaling pathway.

Pre-hatch thermal manipulation of embryos and post-hatch baicalein supplementation mitigated heat stress in broiler chickens

BACKGROUND

High environmental temperatures induce heat stress in broiler chickens, affecting their health and production performance. Several dietary, managerial, and genetics strategies have been tested with some success in mitigating heat stress (HS) in broilers. Developing novel HS mitigation strategies for sustaining broiler production is critically needed. This study investigated the effects of pre-hatch thermal manipulation (TM) and post-hatch baicalein supplementation on growth performance and health parameters in heat-stressed broilers.

RESULTS

Six hundred fertile Cobb 500 eggs were incubated for 21 d. After candling on embryonic day (ED) 10, 238 eggs were thermally manipulated at 38.5 °C with 55% relative humidity (RH) from ED 12 to 18, then transferred to the hatcher (ED 19 to 21, standard temperature) and 236 eggs were incubated at a controlled temperature (37.5 °C) till hatch. After hatch, 180-day-old chicks from both groups were raised in 36 pens (n = 10 birds/pen, 6 replicates per treatment). The treatments were: 1) Control, 2) TM, 3) control heat stress (CHS), 4) thermal manipulation heat stress (TMHS), 5) control heat stress supplement (CHSS), and 6) thermal manipulation heat stress supplement (TMHSS). All birds were raised under the standard environment for 21 d, followed by chronic heat stress from d 22 to 35 (32-33 °C for 8 h) in the CHS, TMHS, CHSS, and TMHSS groups. A thermoneutral (22-24 °C) environment was maintained in the Control and TM groups. RH was constant (50% ± 5%) throughout the trial. All the data were analyzed using one-way ANOVA in R and GraphPad software at P < 0.05 and are presented as mean ± SEM. Heat stress significantly decreased (P < 0.05) the final body weight and ADG in CHS and TMHS groups compared to the other groups. Embryonic TM significantly increased (P < 0.05) the expression of heat shock protein-related genes (HSP70, HSP90, and HSPH1) and antioxidant-related genes (GPX1 and TXN). TMHS birds showed a significant increment (P < 0.05) in total cecal volatile fatty acid (VFA) concentration compared to the CHS birds. The cecal microbial analysis showed significant enrichment (P < 0.05) in alpha and beta diversity and Coprococcus in the TMHSS group.

CONCLUSIONS

Pre-hatch TM and post-hatch baicalein supplementation in heat-stressed birds mitigate the detrimental effects of heat stress on chickens' growth performance, upregulate favorable gene expression, increase VFA production, and promote gut health by increasing beneficial microbial communities.

A comprehensive investigation on the interaction between jaceosidin, baicalein and lipoxygenase: Multi-spectroscopic analysis and computational study

Lipoxygenase (LOX) has the harmful effect of accelerating lipid oxidation, and polyphenols have the inhibitory effect on lipoxygenase. However, there were rare researches investigated on the interactions between polyphenols and LOX. In this study, the binding mechanisms between polyphenols (Jaceosidin-JSD and baicalein-BCL) and LOX were investigated by multi-spectroscopic analysis and computational study. Both JSD and BCL binding to LOX resulted in static fluorescence quenching, and the complexes of JSD-LOX and BCL-LOX were built at a molar ratio of 1:1, respectively. The binding constants of LOX-JSD (72.18 × 105 L/mol at 298 K) and LOX-BCL (12.43 × 105 L/mol at 298 K) indicated that LOX had stronger binding affinity to JSD compared to BCL. Compared with BCL-LOX, the JSD-LOX system formed more hydrogen bonds which ensured a stronger bond between JSD and LOX. The studies in molecular dynamics also demonstrated that the JSD-LOX complex is more stable, and the addition of JSD is more conducive to the complex formation. The current study provides some new insights for the study on the inhibition of lipid oxidation and affords a new strategy for the discovery of novel food preservatives.

VEGF and EGFR signaling pathways are involved in the baicalein attenuation of OVA-induced airway inflammation and airway remodeling in mice

BACKGROUND

Although Traditional Chinese Medicine (TCM) has been used for treating asthma for centuries, the understanding of its mechanism of action is still limited. Thus, the purpose of this study was to explore the possible therapeutic effects, and underlying mechanism of baicalein in the treatment of asthma.

METHODS

Freely availabled atabases (e.g. OMIM, TTD, Genecards, BATMAN-TCM, STITCH 5.0, SEA, SwissTargetPrediction) and software (e.g. Ligplot 2.2.5 and PyMoL) were used for disease drug target prediction and molecular docking by network pharmacology. The efficacy and mechanism of action of baicalein in the treatment of asthma were validated using an ovalbumin (OVA)-induced asthma mouse model and molecular biology techniques.

RESULTS

A total of 1655 asthma-related genes and 161 baicalein-related targets were identified from public databases. Utilizing common databases and software for network pharmacology and molecular docking analysis, seven potential target proteins for the therapeutic effects of baicalein on asthma were selected, including v-akt murine thymoma viral oncogene homolog 1 (AKT1), vascular endothelial growth factor A (VEGFA), epidermal growth factor receptor (EGFR), proto-oncogene tyrosine-protein kinase Src (SRC), mitogen-activated protein kinase 3 (MAPK3), matrix metallopeptidase 9 (MMP9), and MAPK1. In vivo, baicalein treatment via intraperitoneal injection at a dose of 50 mg/kg significantly reduced airway inflammation, collagen deposition, smooth muscle thickness, lung interleukin (IL)-4 and IL-13 levels, peripheral blood immunoglobulin (Ig)E levels, as well as the count and ratio of eosinophils in bronchoalveolar lavage fluid (BALF) in an OVA-induced asthma mouse model. Further validation by reverse transcription quantitative polymerase chain reaction (RT-qPCR) and western blotting analysis revealed that the VEGF and EGFR signaling pathways involving VEGFA, MAPK1, MAPK3, and EGFR were inhibited by baicalein in the asthma mouse model.

CONCLUSION

Baicalein attenuates airway inflammation and airway remodeling through inhibition of VEGF and EGFR signaling pathways in an OVA-induced asthma mouse model. This will provide a new basis for the development of baicalein as a treatment for asthma and highlights the potential of network pharmacology and molecular docking in drug discovery and development.

Baicalin and baicalein in modulating tumor microenvironment for cancer treatment: A comprehensive review with future perspectives

Cancer is a leading cause of death worldwide. The burden of cancer incidence and mortality is increasing rapidly. New approaches to cancer prevention and treatment are urgently needed. Natural products are reliable and powerful sources for anticancer drug discovery. Baicalin and baicalein, two major flavones isolated from Scutellaria baicalensis Georgi, a multi-purpose traditional medicinal plant in China, exhibit anticancer activities against multiple cancers. Of note, these phytochemicals exhibit extremely low toxicity to normal cells. Besides their cytotoxic and cytostatic activities toward diverse tumor cells, recent studies demonstrated that baicalin and baicalein modulate a variety of tumor stromal cells and extracellular matrix (ECM) in the tumor microenvironment (TME), which is essential for tumorigenesis, cancer progression and metastasis. In this review, we summarize the therapeutic potential and the mechanism of action of baicalin and baicalein in the regulation of tumor microenvironmental immune cells, endothelial cells, fibroblasts, and ECM that reshape the TME and cancer signaling, leading to inhibition of tumor angiogenesis, progression, and metastasis. In addition, we discuss the biotransformation pathways of baicalin and baicalein, related therapeutic challenges and the future research directions to improve their bioavailability and clinical anticancer applications. Recent advances of baicalin and baicalein warrant their continued study as important natural ways for cancer interception and therapy.

Baicalein Alleviates Arsenic-induced Oxidative Stress through Activation of the Keap1/Nrf2 Signalling Pathway in Normal Human Liver Cells

BACKGROUND

Oxidative stress is a key mechanism underlying arsenicinduced liver injury, the Kelch-like epichlorohydrin-related protein 1 (Keap1)/nuclear factor E2 related factor 2 (Nrf2) pathway is the main regulatory pathway involved in antioxidant protein and phase II detoxification enzyme expression. The aim of the present study was to investigate the role and mechanism of baicalein in the alleviation of arsenic-induced oxidative stress in normal human liver cells.

METHODS

Normal human liver cells (MIHA cells) were treated with NaAsO2 (0, 5, 10, 20 μM) to observe the effect of different doses of NaAsO2 on MIHA cells. In addition, the cells were treated with DMSO (0.1%), NaAsO2 (20 μM), or a combination of NaAsO2 (20 μM) and Baicalein (25, 50 or 100 μM) for 24 h to observe the antagonistic effect of Baicalein on NaAsO2. Cell viability was determined using a Cell Counting Kit- 8 (CCK-8 kit). The intervention doses of baicalein in subsequent experiments were determined to be 25, 50 and 100μM. The intracellular content of reactive oxygen species (ROS) was assessed using a 2',7'-dichlorodihydrofluorescein diacetate (DCFHDA) probe kit. The malonaldehyde (MDA), Cu-Zn superoxide dismutase (Cu-Zn SOD) and glutathione peroxidase (GSH-Px) activities were determined by a test kit. The expression levels of key genes and proteins were determined by real-time fluorescence quantitative polymerase chain reaction (qPCR) and Western blotting.

RESULTS

Baicalein upregulated the protein expression levels of phosphorylated Nrf2 (p-Nrf2) and nuclear Nrf2, inhibited the downregulation of Nrf2 target genes induced by arsenic, and decreased the production of ROS and MDA. These results demonstrate that baicalein promotes Nrf2 nuclear translocation by upregulating p-Nrf2 and inhibiting the downregulation of Nrf2 target genes in arsenic-treated MIHA cells, thereby enhancing the antioxidant capacity of cells and reducing oxidative stress.

CONCLUSION

Baicalein alleviated arsenic-induced oxidative stress through activation of the Keap1/Nrf2 signalling pathway in normal human liver cells.

Environment-relevant concentrations of cadmium induces necroptosis and inflammation; baicalein maintains gill homeostasis through suppressing ROS/ER stress signaling in common carps (Cyprinus carpio L.)

Cadmium (Cd) is a major contaminant in natural environments and exerts adverse effects on aquatic biota at low concentrations. Gill is as vital respiratory organ and may cause pollutants to enter fish during gas exchange. Baicalein (BAI), as a kind of flavonoids, possess antioxidant properties through inactivating free radicals. To confirm the potential effects and approaches of BAI addition in maintaining the gill stability, 90 common carps (Cyprinus carpio L.) were selected and randomly divided into water environment exposure group (0.22 mg/L Cd) and/or feed added with 0.10 g/kg BAI for 30 days. The analysis of ion content in serum showed that Cd exposure disturbed ion homeostasis, and BAI could reduce serum Cd concentration. The histopathological results of gills showed that Cd exposure caused gill tissue lesions and structural damage, and BAI feeding effectively alleviated this damage. In addition, BAI could enhance antioxidant activity and activate Nrf2/HO-1 axis, thereby reducing oxidative stress and endoplasmic reticulum (ER) stress. Moreover, BAI lightened cytokine imbalance, inflammatory response, and necroptosis. Overall, the results indicated that BAI feeding could maintain gill homeostasis against Cd poisoning via the ROS/ER stress signaling. This trial revealed the properties of BAI resistance to metal Cd in aquaculture and partially elucidated its mechanism.

Baicalin Induces Gastric Cancer Cell Pyroptosis through the NF-κB-NLRP3 Signaling Axis

Pyroptosis, a highly regulated form of cell death, could hold the key to revolutionizing cancer treatment. With cancer posing a significant global health challenge due to its high morbidity and mortality rates, exploring unconventional therapeutic approaches becomes imperative. Chinese medicine, renowned for its holistic principles, presents intriguing possibilities for treating gastric cancer (GC). Notably, baicalin, a prominent component found in the traditional Chinese herb Scutellaria baicalensis Georgi, has shown promising clinical potential in gastric cancer treatment.To shed light on this intriguing phenomenon, a multidisciplinary approach was undertaken, combining systems biology, bioinformatics, and in vitro studies. The primary objective was to unravel the intricate workings underlying baicalein's ability to promote gastric cancer cell pyroptosis.The findings from this comprehensive study unveiled an essential signaling axis involving NF-κB-NLRP3, which plays a pivotal role in the process of baicalein-induced pyroptosis in gastric cancer cells. As the investigation progressed, it became evident that baicalein exhibited a remarkable capability to reverse the effects of the NLRP3 inhibitor, MCC950 Sodium. Excitingly, the efficacy of cell pyroptosis induction by baicalein demonstrated a discernible dose-dependent relationship, showcasing its potential as a valuable therapeutic agent.The complex nature of these findings underscores the intricate interplay between baicalein, NF-κB-NLRP3 signaling, and gastric cancer cell pyroptosis. As the scientific community delves deeper into the world of Pyroptosis and its therapeutic implications, baicalein's potential as a game-changer in the fight against gastric cancer becomes increasingly evident.

The Inhibition Mechanism of Pancreatic Ductal Adenocarcinoma via LXR Receptors: A Multifaceted Approach Integrating Molecular Docking, Molecular Dynamics and Post-MD Inter-Molecular Contact Analysis

OBJECTIVE

Pancreatic ductal adenocarcinoma (PDAC) has an unfavorable outlook due to its aggressive characteristics, delayed diagnosis, and limited effective treatment options for advanced stages of the disease. The significant mortality rate has prompted investigations into additional factors that could aid in managing this type of cancer. Liver X receptors, specifically LXRα and LXRβ, are nuclear receptors that oversee the expression of genes related to cholesterol, glucose, lipid metabolism, and inflammatory responses. LXRs have also emerged as potential targets for addressing PDAC, and recent findings have demonstrated that LXR ligands can impede cell proliferation in various cancer forms, notably pancreatic cancer. This comprehensive computational research study involving oncological in silico mechanism discovery explored inhibitory ligands for Liver X receptors (LXRα and LXRβ), which are believed to have prognostic significance in PDAC.

METHODS

The study utilized Baicalein, Beta-Sitosterol, Polydatin ligands in molecular docking and dynamics and post-molecular Hydrogen bonding contact analyses dynamics to characterize receptor inhibition.

RESULT

The outcomes suggest that Baicalein exhibits versatile inhibitory effects on both receptors, while Beta-Sitosterol emerges as a highly effective inhibitor of LXRβ.

CONCLUSION

Further in vitro and in vivo investigations will be beneficial and would shed light onto the mechanism to decipher the suppression of PDAC evaluating the potential of Baicalein, Beta-Sitosterol, Polydatin natural ligand compounds.

Baicalein ameliorates oxidative stress and brain injury after intracerebral hemorrhage by activating the Nrf2/ARE pathway via miR-106a-5p/PHLPP2 axis

Intracerebral hemorrhage (ICH) is a devastating stroke subtype. Baicalein (BAI) has been reported to be effective in ischemic stroke. The aim of the present study was to investigate the mechanism of BAI on brain injury after ICH. Firstly, ICH mouse models were established by injecting collagenase into the right of basal ganglia, followed by detection of neurobehavioral scores, brain edema, oxidative stress (OS) level, neuronal apoptosis and pathological changes. Average neurologic scores, brain water content, and blood-brain barrier permeability and MDA level in ICH mice were reduced after BAI treatment, while serum SOD and GSH-Px levels were increased and neuronal apoptosis and pathological injury of the brain tissues were mitigated. miR-106a-5p downregulation averted the effect of BAI on ICH mice. miR-106a-5p targeted PHLPP2 and PHLPP2 overexpression reversed the effect of BAI on ICH mice. BAI activated the Nrf2/ARE pathway by inhibiting PHLPP2 expression. In conclusion, BAI inhibited OS and protected against brain injury after ICH by activating the Nrf2/ARE pathway through the miR-106a-5p/PHLPP2 axis.

Glutathione metabolism rewiring protects renal tubule cells against cisplatin-induced apoptosis and ferroptosis

Renal proximal tubular cells are highly vulnerable to different types of assaults during filtration and reabsorption, leading to acute renal dysfunction and eventual chronic kidney diseases (CKD). The chemotherapeutic drug cisplatin elicits cytotoxicity causing renal tubular cell death, but its executing mechanisms of action are versatile and elusive. Here, we show that cisplatin induces renal tubular cell apoptosis and ferroptosis by disrupting glutathione (GSH) metabolism. Upon cisplatin treatment, GSH metabolism is impaired leading to GSH depletion as well as the execution of mitochondria-mediated apoptosis and lipid oxidation-related ferroptosis through activating IL6/JAK/STAT3 signaling. Inhibition of JAK/STAT3 signaling reversed cell apoptosis and ferroptosis in response to cisplatin induction. Using a cisplatin-induced acute kidney injury (CAKI) mouse model, we found that inhibition of JAK/STAT3 significantly mitigates cisplatin nephrotoxicity with a reduced level of serum BUN and creatinine as well as proximal tubular distortion. In addition, the GSH booster baicalein also reclaims cisplatin-induced renal tubular cell apoptosis and ferroptosis as well as the in vivo nephrotoxicity. In conclusion, cisplatin disrupts glutathione metabolism, leading to renal tubular cell apoptosis and ferroptosis. Rewiring glutathione metabolism represents a promising strategy for combating cisplatin nephrotoxicity.

Baicalein improves the chemoresistance of ovarian cancer through regulation of CirSLC7A6

PURPOSE

The present study aimed to investigate whether baicalein improves the sensitivity of resistant ovarian cancer cells to cisplatin.

METHODS

Transcriptomic sequencing and bioinformatics analysis were used to screen differentially expressed CirSLC7A6 in A2780 and A2780/CDDP cells. RT-qPCR was performed to examine the expression levels of CirSLC7A6, miR-2682-5p, and SLC7A6. Cell proliferation and apoptosis were examined using a Cell Counting Kit-8 assay and flow cytometry, and cell migration and invasion were analyzed using wound healing and Transwell assays. Cell suspensions were inoculated into the subcutaneous tissues of the bilateral interscapular region of nude mice. Saline, cisplatin, baicalein and cisplatin plus baicalein were intraperitoneally injected to observe the effects on tumor growth. Toxicity analyses in the liver and kidney were performed using H&E staining. RT-qPCR and immunohistochemistry were used to detect the expression of CirSLC7A6, miR-2682-5p, and SLC7A6 in tumor tissues, and western blot analysis was carried out to measure protein expression levels.

RESULTS

CirSLC7A6 was markedly upregulated in A2780/CDDP cells compared with the A2780 cells. CirSLC7A6 knockdown notably increased the expression of miR-2682-5p and decreased SLC7A6 expression. The rates of inhibition and apoptosis in the group treated with a combination of cisplatin and baicalein were significantly higher than those of the cisplatin and baicalein groups of A2780/CDDP shCirSLC7A6 cells. In A2780/CDDP shCirSLC7A6 cells, migration and invasion were significantly higher in the cisplatin and baicalein groups, compared with the combined treatment group. In the A2780/CDDP shCirSLC7A6 cell xenograft, the tumor weight of the combined treatment group was significantly lower than that of the cisplatin and baicalein groups. In addition, the combination of cisplatin and baicalein did not induce higher levels of toxicity in the liver or kidney. Baicalein alone and in combination with cisplatin notably reduced the expression of CirSLC7A6 and SLC7A6, and increased the expression of miR-2682-5p in the A2780/CDDP shCirSLC7A6 cell xenograft. In A2780/CDDP shCirSLC7A6 cells, the expression levels of P-Akt, P-mTOR, P-Erk, Bcl-2 and MMP2 were lower in the combined treatment group than in the control group.

CONCLUSIONS

Treatment with baicalein improved the sensitivity of ovarian cancer cells to cisplatin and inhibited cell proliferation, metastasis and tumor growth.

Baicalein inhibits apoptosis and autophagy induced by chlorpyrifos exposure to kidney of Cyprinus carpio through activation of PI3K/AKT pathway

Chlorpyrifos (CPF), a widely used organophosphate pesticide that has caused large-scale contamination globally, has become a major concern. Baicalein (BAI), as a flavonoid extract, shows anti-inflammatory as well as antioxidant activities. The kidneys of fish serve to excrete toxins and are major target organs for environmental contaminants. However, it is not obvious whether BAI can counteract the damage caused by CPF exposure to fish kidneys. Therefore, we conducted a 30-day simulation of CPF poisoning and/or BAI treatment by adding 23.2 μg/L CPF to water and/or 0.15 g/kg BAI to feed. In the transmission electron microscopy results, we observed obvious phenomenon of autophagy and apoptosis in the CPF group, and the TUNEL staining and immunofluorescence of LC3B and p62 double-staining results confirmed that CPF induced autophagy and apoptosis in the kidney of common carp. Furthermore, CPF induced the increase of ROS level and inhibition of PI3K and Nrf2 pathways, which in turn triggered oxidative stress, autophagy and apoptosis in carp kidney according to western blot, RT-qPCR and kit assays. However, addition of BAI significantly alleviated oxidative stress, autophagy and apoptosis due to binding to PI3K protein. Additionally, through phylogenetic tree and structural domain analyses, we also found that the binding sites of BAI and PI3K are conserved in a variety of representative species. These results suggest that BAI antagonizes CPF-caused renal impairments in carp involving the PI3K/AKT pathway and the Nrf2 pathway. Our findings provide new insights into the nephrotoxicity effects of CPF and the potential use of BAI as a detoxification agent for CPF intoxication.

Baicalein promotes the microglia M2 polarization and suppresses apoptosis by targeting HMOX1/PDE4D to alleviate Alzheimer's disease

Alzheimer's disease (AD) is a neurodegenerative disorder that has quickly becoming one of the most expensive, lethal, and burdening diseases of this century. In the past twenty years, hundreds of drugs have been tested while only several have been authorized by FDA for AD treatment, hence, searching for candidate agent with therapeutic potential for AD is imminent. Controlling polarization direction of microglia is crucial in AD therapy. Recent research suggests that baicalein has potential to reduce neuroinflammation and prevent neurodegenerative diseases by affecting microglia, while the specific molecular mechanism of baicalein in regulating microglia in the treatment of AD is still unclear. In this study, we investigated how baicalein affected microglial polarization in AD and potential biological mechanisms. In cell experiments, it was verified that baicalein significantly shifted the BV-2 microglia phenotype from the pro-inflammatory M1 to the anti-inflammatory M2 phenotype, inhibited the microglial apoptosis and pro-inflammatory factors, promoted the microglial Aβ uptake and anti-inflammatory factors after LPS stimulated. In APP/PS1 mice, it was found that baicalein decreased the Aβ plaque deposition in brain, attenuated NLRP3 inflammasome activation and neuronal apoptosis in APP/PS1 mice. Furthermore, bioinformatics analysis and experiment validated that HMOX1 is a target of baicalein, and we elucidated that baicalein modulated the microglial polarization to inhibit neuroinflammation and neural injury through targeting on the HMOX1/PDE4D axis in AD. In conclusion, our findings indicate the therapeutic effect of baicalein for AD, and baicalein might serve a potential agent for AD treatment.

Herbal combinations against COVID-19: A network pharmacology, molecular docking and dynamics study

OBJECTIVE

The aim of this study is to identify molecules from traditional Chinese medicine (TCM) with potential activity against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its variants.

METHODS

We applied the Apriori algorithm to identify important combinations of herbs in the TCM prescriptions for the treatment of coronavirus disease 2019 (COVID-19). Then, we explored the active components and core targets using network pharmacology. In addition, the molecular docking approach was performed to investigate the interaction of these components with the main structural and non-structural proteins, as well as the mutants. Furthermore, their stability in the binding pockets was further evaluated with the molecular dynamics approach.

RESULTS

A combination of Amygdalus Communis Vas., Ephedra Herba and Scutellaria baicalensis Georgi was selected as the important herbal combination, and 11 main components and 20 core targets against COVID-19 were obtained. These components, including luteolin, naringenin, stigmasterol, baicalein, and so on, were the potentially active compounds against COVID-19. The binding affinity of these compounds with the potential targets was as high as the positive controls. Among them, baicalein could interfere with multiple targets simultaneously, and it also interfered with the interaction between spike protein and angiotensin-converting enzyme 2 receptor. Additionally, almost all the systems reached stability during dynamics simulation.

CONCLUSION

The combination of A. communis, Ephedra Herba and S. baicalensis was the most important herbal combination for the treatment of COVID-19. Baicalein may be a potential candidate against SARS-CoV-2 and its variants. Please cite this article as: Song JB, Zhao LQ, Wen HP, Li YP. Herbal combinations against COVID-19: A network pharmacology, molecular docking and dynamics study. J Integr Med. 2023;21(6):593-604.

Baicalein Attenuates Neuroinflammation in LPS-Treated BV-2 Cells by Inhibiting Glycolysis via STAT3/c-Myc Pathway

More and more evidence shows that metabolic reprogramming is closely related to the occurrence of AD. The metabolic conversion of oxidative phosphorylation into glycolysis will aggravate microglia-mediated inflammation. It has been demonstrated that baicalein could inhibit neuroinflammation in LPS-treated BV-2 microglial cells, but whether the anti-neuroinflammatory mechanisms of baicalein were related to glycolysis is unclear. Our results depicted that baicalein significantly inhibited the levels of nitric oxide (NO), interleukin-6 (IL-6), prostaglandin 2 (PGE2) and tumor necrosis factor (TNF-α) in LPS-treated BV-2 cells. 1H-NMR metabolomics analysis showed that baicalein decreased the levels of lactic acid and pyruvate, and significantly regulated glycolytic pathway. Further study revealed that baicalein significantly inhibited the activities of glycolysis-related enzymes including hexokinase (HK), 6-phosphate kinase (6-PFK), pyruvate kinase (PK), lactate dehydrogenase (LDH), and inhibited STAT3 phosphorylation and c-Myc expression. By using of STAT3 activator RO8191, we found that baicalein suppressed the increase of STAT3 phosphorylation and c-Myc expression triggered by RO8191, and inhibited the increased levels of 6-PFK, PK and LDH caused by RO8191. In conclusion, these results suggested that baicalein attenuated the neuroinflammation in LPS-treated BV-2 cells by inhibiting glycolysis through STAT3/c-Myc pathway.

Oral metronomic therapy of pancreatic cancer with gemcitabine and paclitaxel co-loaded in lecithin-based Self-Nanoemulsifying preconcentrate (LBSNEP)

This study aimed to evaluate gemcitabine (GEM)/paclitaxel (PTX) co-loaded into a lecithin-based self-nanoemulsifying preconcentrate (LBSNEP) orally administered in a metronomic therapeutic manner against pancreatic cancer. LBSNEP was developed and evaluated, composed of Caproyl 90, Tween80, lecithin, TPGS, and propyl glycol at a ratio of 20:20:30:5:25, resulting in a droplet diameter of approximately 180 nm. Cell viability studies on MIA PaCa-2 demonstrated a synergetic effect at a proportion of 1:2 between PTX and GEM. Additionally, LBSNEP and baicalein (BAI) were demonstrated to prevent GEM from being deaminated by cytidine deaminase. The combination of GEM, PTX, and BAI in the LBSNEP showed good dissolution in simulated gastric fluid. The pharmacokinetic study conducted on rats showed that co-administration of GEM, PTX, and BAI in the LBSNEP enhanced the respective relative oral bioavailability levels of GEM and PTX by 1.5- and 2-fold, respectively, compared to the solution group. The tumor inhibition study was conducted with metronomic therapy at a low daily dose compared to conventional therapy at a higher dose every 3 days. Results indicated that oral metronomic delivery of GEM/PTX/BAI LBSNEP could inhibit tumor growth during administration phase, and that there were similar tumor volumes compared to traditional chemotherapy at day 28 even if the dose of metronomic chemotherapy was 2.2-fold less than that of the latter. In conclusion, a self-nanoemulsifying drug-delivery system for the oral delivery of GEM, PTX, and BAI in a metronomic manner enhanced the therapeutic effect on pancreatic cancer, providing an alternative option for chemotherapy.

Baicalein mitigates oxidative stress and enhances lifespan through modulation of Wnt ligands and GATA factor: ELT-3 in Caenorhabditis elegans

AIMS

Age predispose individual to major diseases, and the biological processes contributing to aging are currently under intense investigation. Hence, plant-based natural compounds could be a potential target to counteract aging and age-associated diseases. So, the present study aims to investigate the antiaging properties of a natural compound Baicalein (BAI) on C. elegans and to elucidate the pathways or signaling molecules involved.

METHODS

Herein, we investigated the inhibitory effects of BAI on different Wnt ligands of C. elegans and its underlying mechanisms. Moreover, we monitored BAI's antiaging effect on the worms' lifespan and its different aging parameters. We employed different mutant and transgenic C. elegans strains to identify the pathways and transcription factors involved.

KEY FINDINGS

We first showed that BAI could downregulate different Wnt ligands mRNA expressions in C. elegans, resulting in enhanced expression of GATA transcription factor ELT-3 and antiaging gene Klotho. On further evaluation, it was observed that BAI could enhance the worm's lifespan via ELT-3 and SKN-1 transcription factors, whereas, for the protection of worms against external oxidative stress, both ELT-3 and DAF-16 transcription factors were involved. Moreover, sensitive aging parameters of worms, including lipofuscin and ROS accumulation, and the declined physiological and mechanical functions observed in aged worms were ameliorated by BAI.

SIGNIFICANCE

This study highlighted BAI as a promising antiaging compound. This study also revealed the Wnt inhibitory potential of BAI with future implications for pharmacological target of age-associated diseases with aberrant activation of the Wnt pathway.

Baicalein ameliorates polymyxin B-induced acute renal injury by inhibiting ferroptosis via regulation of SIRT1/p53 acetylation

The polypeptide antibiotic Polymyxin B (PMB) can cause acute kidney injury (AKI), we found that ferroptosis is one of the main mechanisms of renal injury caused by PMB. It was reported that baicalein can inhibit ferroptosis. Therefore, in this study we examined whether baicalein could attenuate PMB-induced renal injury by inhibiting ferroptosis. We confirmed that baicalein could reduce PMB-induced renal injury in vivo and in vitro studies. In the in vitro study, baicalein significantly increased the survival rate of human HK2 tubular epithelial cells. The results of HE staining and electron microscopy in mice also showed that baicalein reduced PMB-induced renal injury, and significantly decreased the levels of BUN and Scr. By detecting ferroptosis-related indicators, we found that pre-incubation of baicalein in HK2 cells down-regulated Fe2+ level, lipid peroxidation, MDA and HO-1 which had been increased by PMB. Furthermore, baicalein up-regulated the levels of SCL7A11, GPX4 and GSH that were decreased by PMB. Moreover, intraperitoneal injection of baicalein in the animal model down-regulated kidney iron level, PTGS2 and 4HNE, and increased the GSH level, which suggested that baicalein could inhibit PMB-induced ferroptosis. Finally, by detecting changes in levels of p53 and p53 K382 acetylation, baicalein was observed to decrease elevated p53 K382 acetylation after PMB treatment, further confirming that baicalein inhibits ferroptosis by reducing p53 K382 acetylation via upregulation of SIRT1 expression. In conclusion, these results suggest that baicalein decreases p53 acetylation level by elevating SIRT1, which can then inhibit PMB-induced ferroptosis and ultimately attenuates AKI.

Active compounds and potential targets of Shuganning injection in the treatment of hepatocellular carcinoma by network pharmacology and in vitro validation

Shuganning injection (SGNI), a TCM (traditional Chinese medicine) injection with good hepatoprotective effects, exerted therapeutic effects on hepatocellular carcinoma (HCC). However, the active compounds and effects of SGNI on HCC remain unclear. The objective of this study was to investigate the active compounds and potential targets of SGNI in the treatment of HCC, and explore the molecular mechanisms of main compounds. Network pharmacology was applied to predict the active compounds and targets of SGNI on cancer. The interactions between active compounds and target proteins were validated by drug affinity responsive target stability (DARTS), cellular thermal shift assay (CETSA), and pull-down assay. The in vitro test of the effects and mechanism of vanillin and baicalein was elucidated by MTT, western blot, immunofluorescence, and apoptosis analysis. According to compound characteristics, targets, etc., two typical active ingredients (vanillin and baicalein) were selected as representatives to explore the effects on HCC. Vanillin (an important food additive) bound to NF-κB1 and baicalein (a bioactive flavonoid) bound to FLT3 (FMS-like tyrosine kinase 3) were confirmed in this study. Vanillin and baicalein both inhibited cell viability and promoted apoptosis of Hep3B and Huh7 cells. In addition, both vanillin and baicalein could enhance the activation of the p38/MAPK (mitogen-activated protein kinase) signaling pathway, which may partially explain the anti-apoptosis effects of the two compounds. In conclusion, two active compounds of SGNI, vanillin and baicalein, promoted apoptosis of HCC cells via binding with NF-κB1 or FLT3, and regulating the p38/MAPK pathway. Baicalein and vanillin may be good candidates for HCC treatment on drug development.

Androgen receptor and hyaluronan-mediated motility receptor as new molecular targets of baicalein: new molecular mechanisms for its anticancer properties

Natural compounds known as phytochemicals have served as valuable resources for the development of new anti-cancer drugs and treatment of malignancies. Among these phytochemicals, baicalein is an emerging anti-tumor flavonoid obtained from Scutellaria baicaleinsis (Lamiaceae), but its underlying mechanisms of action and molecular targets have not yet been completely elucidated. Here, we identified new mechanisms for the anti-tumor activities of baicalein, providing evidence that hyaluronan-mediated motility receptor (HMMR) and androgen receptor (AR) are new molecular targets of baicalein in human cancer cells. We observed that HMMR, known to be highly associated with poor prognosis in a wide range of human cancers, was substantially downregulated by baicalein at mRNA and protein levels. Reporter assays further revealed that the suppression of HMMR by baicalein might occur through a transcriptional regulatory mechanism with the participation of Egr-1, E2F3α, and serum response factor (SRF). We also found that baicalein significantly inhibits androgenic responses in hormone-responsive prostate cancer cells, indicating that this might be attributed to the downregulation of AR promoter activity by baicalein. Additionally, baicalein markedly induced the expression of tumor suppressive miR-30C, which might be partly involved in baicalein-mediated autophagy and anti-cancer effects. Overall, our study sheds light on new diverse mechanisms of the anti-cancer effects exhibited by baicalein, implying that baicalein could be a potential therapeutic agent against human cancers and function as an inhibitor of HMMR and AR.

The role of redox active copper(II) on antioxidant properties of the flavonoid baicalein: DNA protection under Cu(II)-Fenton reaction and Cu(II)-ascorbate system conditions

The antioxidant properties of flavonoids are mediated by their functional hydroxyl groups, which are capable of both chelating redox active metals such as iron, copper and scavenging free radicals. In this paper, the antioxidant vs. prooxidant and DNA protecting properties of baicalein and Cu(II)-baicalein complexes were studied under the conditions of the Copper-Fenton reaction and of the Copper-Ascorbate system. From the relevant EPR spectra, the interaction of baicalein with Cu(II) ions was confirmed, while UV-vis spectroscopy demonstrated a greater stability over time of Cu(II)-baicalein complexes in DMSO than in methanol and PBS and Phosphate buffers. An ABTS study confirmed a moderate ROS scavenging efficiency, at around 37%, for both free baicalein and Cu(II)-baicalein complexes (in the ratios 1:1 and 1:2). The results from absorption titrations are in agreement with those from viscometric studies and confirmed that the binding mode between DNA and both free baicalein and Cu-baicalein complexes, involves hydrogen bonds and van der Waals interactions. The DNA protective effect of baicalein has been investigated by means of gel electrophoresis under the conditions of the Cu-catalyzed Fenton reaction and of the Cu-Ascorbate system. In both cases, it was found that, at sufficiently high concentrations, baicalein offers some protection to cells from DNA damage caused by ROS (singlet oxygen, hydroxyl radicals and superoxide radical anions). Accordingly, baicalein may be useful as a therapeutic agent in diseases with a disturbed metabolism of redox metals such as copper, for example Alzheimer's disease, Wilson's disease and various cancers. While therapeutically sufficient concentrations of baicalein may protect neuronal cells from Cu-Fenton-induced DNA damage in regard to neurological conditions, conversely, in the case of cancers, low concentrations of baicalein do not inhibit the pro-oxidant effect of copper ions and ascorbate, which can, in turn, deliver an effective damage to DNA in tumour cells.

An overview of anti-SARS-CoV-2 and anti-inflammatory potential of baicalein and its metabolite baicalin: Insights into molecular mechanisms

The current Coronavirus Disease 2019 (COVID-19) pandemic, caused by the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), is highly contagious infection that breaks the healthcare systems of several countries worldwide. Till to date, no effective antiviral drugs against COVID-19 infection have reached the market, and some repurposed drugs and vaccines are prescribed for the treatment and prevention of this disease. The currently prescribed COVID-19 vaccines are less effective against the newly emergent variants of concern of SARS-CoV-2 due to several mutations in viral spike protein and obviously there is an urgency to develop new antiviral drugs against this disease. In this review article, we systematically discussed the anti-SARS-CoV-2 and anti-inflammatory efficacy of two flavonoids, baicalein and its 7-O-glucuronide, baicalin, isolated from Scutellaria baicalensis, Oroxylum indicum, and other plants as well as their pharmacokinetics and oral bioavailability, for development of safe and effective drugs for COVID-19 treatment. Both baicalein and baicalin target the activities of viral S-, 3CL-, PL-, RdRp- and nsp13-proteins, and host mitochondrial OXPHOS for suppression of viral infection. Moreover, these compounds prevent sepsis-related inflammation and organ injury by modulation of host innate immune responses. Several nanoformulated and inclusion complexes of baicalein and baicalin have been reported to increase oral bioavailability, but their safety and efficacy in SARS-CoV-2-infected transgenic animals are not yet evaluated. Future studies on these compounds are required for use in clinical trials of COVID-19 patients.

Baicalein Inhibits α-Melanocyte-stimulating Hormone-stimulated Melanogenesis via p38 Mitogen-activated Protein Kinase Pathway in B16F10 Mouse Melanoma Cells

Excessive UVB exposure causes development of both malignant and non-malignant melanoma via the secretion of α-melanocyte-stimulating hormone (α-MSH). We investigated whether baicalein (5,6,7-trihydroxyflavone) could inhibit α-MSH-stimulated melanogenesis. Baicalein prevented UVB- and α-MSH-induced melanin production and attenuated α-MSH-stimulated tyrosinase (monophenol monooxygenase) activity, and expression of tyrosinase and tyrosine-related protein-2. In addition, baicalein prevented melanogenesis and pigmentation via the p38 mitogen-activated protein kinases signaling pathway. These findings suggest that baicalein represents a natural compound for attenuating melanogenesis.

System analysis of Huang-Lian-Jie-Du-Tang and their key active ingredients for overcoming CML resistance by suppression of leukemia stem cells

BACKGROUND

BCR-ABL1-based resistance to imatinib, mainly resulting from BCR-ABL1 mutations, is largely solved after second- and third-generation tyrosine kinase inhibitors (TKIs) are discovered. Nonetheless, imatinib resistance without BCR-ABL1 mutations, including intrinsic resistance induced by stem cells within chronic myeloid leukemia (CML), remains the major clinical challenge for many patients.

PURPOSE

To study the key active ingredients and corresponding target proteins in Huang-Lian-Jie-Du-Tang (HLJDT) against BCR-ABL1-independent CML resistance to therapeutics, and then explore its mechanism of against CML drug resistance.

METHODS

Cytotoxicity of HLJDT and its active ingredients in BCR-ABL1-independent imatinib resistance cells was analyzed through MTT assay. The cloning ability was measured through soft agar assay. Monitoring therapeutic effect on Xenografted mice CML model by in vivo imaging technology and mice survival time. Predicting the potential target protein binding sites by the technology of photocrosslinking sensor chip, molecular space simulation docking, and use Surface Plasmon Resonance (SPR) technology . Flow cytometry to detect the ratio of stem progenitor cells (CD34+). Constructing bone marrow transplantation mice CML leukemia model, detect the effects on leukemia stem cells LSK (Lin-\ Sca-1+ \C-kit+) self-renewal.

RESULTS

Treatment with HLJDT, berberine and baicalein inhibited cell viability and colony formation of BCR-ABL1-independent imatinib-resistant cells in vitro while prolonging survival in mouse with CML xenografts and transplatation CML-like mouse models in vivo. JAK2 and MCL1were identified as targets of berberine and baicalein. JAK2 and MCL1 are involved in multi-leukemia stem cell-related pathways. Moreover, the ratio of CD34+ cells in resistant CML cells is higher than in treatment-sensitive CML cells. Treatment with BBR or baicalein partially suppressed CML leukemic stem cells (LSCs) self-renewal in vitro and in vivo.

CONCLUSION

From the above, we concluded that HLJDT and its key active ingredients (BBR and baicalein) allowed to overcome imatinib resistance with BCR-ABL1 independent by eradication of LSCs by targeting the JAK2 and MCL1 protein levels. Our results lay the foundation for applying HLJDT in patients with TKI-resistant CML.

Baicalin suppressed necroptosis and inflammation against chlorpyrifos toxicity; involving in ER stress and oxidative stress in carp gills

Chlorpyrifos (CPF) has caused large-scale pollution worldwide and posed a threat to non-target organisms. Baicalein (BAI) is a flavonoid extract with anti-oxidant and anti-inflammatory activities. The gills are the mucosal immune organ and the first physical barrier of fish. However, it is not clear whether BAI counteracts organophosphorus pesticide CPF exposure-caused gill damage. Therefore, we established the CPF exposure and BAI intervention models by adding 23.2 μg/L CPF in water and/or 0.15 g/kg BAI in feed for 30 days. The results showed that CPF exposure could cause gill histopathology lesions. Moreover, CPF exposure led to endoplasmic reticulum (ER) stress, caused oxidative stress and Nrf2 pathway activation, and triggered NF-κB-mediated inflammation reaction and necroptosis in carp gills. BAI adding effectively relieved the pathological changes, and lighten inflammation and necroptosis involving in the elF2α/ATF4 and ATF6 pathways through binding to GRP78 protein. Moreover, BAI could ease oxidative stress, but did not affect Nrf2 pathway in carp gills under CPF exposure. These results suggested that BAI feeding could alleviate necroptosis and inflammation against chlorpyrifos toxicity through elF2α/ATF4 and ATF6 axis. The results partially explained the poisoning effect of CPF, and showed BAI could be act as an antidote for organophosphorus pesticides.

Network pharmacology and experiments in vivo and in vitro reveal that the Jia-Wei-Bu-Shen-Yi-Qi formula (JWBSYQF) and its active ingredient baicalein ameliorate BLM-induced lung fibrosis in mice via PI3K/Akt signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Jia-Wei-Bu-Shen-Yi-Qi formula (JWBSYQF), a classical traditional Chinese herbal formula consisting of five herbs, is used clinically in China to treat inflammatory lung diseases, including asthma, chronic obstructive pulmonary disease (COPD) and idiopathic pulmonary fibrosis (IPF). Its mechanism for treating asthma and COPD has been reported, however, how it works against IPF remains unclear.

RESEARCH PURPOSE

Our study aims to observe the therapeutic effect of JWBSYQF on pulmonary fibrosis and further identify the potential active ingredients and molecular pathways.

RESEARCH METHODS

In this study, we used a bleomycin-induced mouse model to investigate the therapeutic effect of JWBSYQF on pulmonary fibrosis. To further explore the potential effective ingredients and molecular pathways, we used the network pharmacology approach to construct a drug-ingredient-target network of JWBSYQF. Then, the common target set was established for JWBSYQF, fibroblast, and lung fibrosis. Analyses of the KEGG pathway, GO enrichment, and network topology were performed to identify key biological processes and molecular pathways for the common targets. Finally, a TGF-β-induced NIH/3T3 proliferation and activation model was used to validate the possible active ingredients and signaling pathways.

RESEARCH RESULTS

JWBSYQF reversed BLM-induced balf leukocyte levels, pulmonary inflammatory lesions and fibrotic collagen deposition in mice and reduced the levels of a-SMA, Col1a1 and TGF-β. A total of 86 active ingredients were identified, 12 of which were considered as potential effective ingredients, while only baicalein effectively improved TGF-β-induced proliferation and activation of NIH/3T3. KEGG results showed that PI3K/Akt signaling pathway may be the potential action mechanism, and Western Blot demonstrated that both JWBSYQF and baicalein downregulated the protein levels of p-PI3K and p-Akt. The molecular docking results suggested that baicalein may directly act on the catalytic and regulatory subunits of PI3K, and this a effect is stronger than direct binding to Akt1.

CONCLUSIONS

Our study revealed that baicalein may be the material basis for JWBSYQF in the treatment of pulmonary fibrosis, and the PI3K/Akt signaling pathway may be a common pathway of action for JWBSYQF and baicalein.

The transcription factors SbMYB45 and SbMYB86.1 regulate flavone biosynthesis in Scutellaria baicalensis

Scutellaria baicalensis Georgi is an important Chinese medicinal plant that is rich in the flavones baicalin, wogonoside, and wogonin, providing it with anti-cancer, anti-inflammatory, and antibacterial properties. However, although the biosynthetic pathways of baicalin and its derivates have been elucidated, the regulation of flavone biosynthesis in S. baicalensis is poorly understood. Here, we found that the contents of baicalin and its derivates increased and that baicalin biosynthetic pathway genes were induced in response to light, and baicalin and baicalein are not exclusively produced in the roots of S. baicalensis. Based on the fact that MYB transcription factors are known to play important roles in flavone biosynthesis, we identified SbMYB45 and SbMYB86.1 in S. baicalensis and determined that they bind to the promoter of the flavone biosynthesis gene SbCHI to enhance its transcription. Moreover, overexpressing SbMYB45 and SbMYB86.1 enhanced the accumulation of baicalin in S. baicalensis leaves. We demonstrate that SbMYB45 and SbMYB86.1 bind to the cis-acting element MBSII in the promoter of CHI to redundantly induce its expression upon light exposure. These findings indicate that SbMYB45 and SbMYB86.1 transcriptionally activate SbCHI in response to light and enhance flavone contents in S. baicalensis.

Investigation of the activity of baicalein towards Zika virus

BACKGROUND

Zika virus (ZIKV) is a mosquito transmitted virus spread primarily by Aedes species mosquitoes that can cause disease in humans, particularly when infection occurs in pregnancy where the virus can have a significant impact on the developing fetus. Despite this, there remains no prophylactic agent or therapeutic treatment for infection. Baicalein is a trihydroxyflavone, that is found in some traditional medicines commonly used in Asia, and has been shown to have several activities including antiviral properties. Importantly, studies have shown baicalein to be safe and well tolerated in humans, increasing its potential utilization.

METHODS

This study sought to determine the anti-ZIKV activity of baicalein using a human cell line (A549). Cytotoxicity of baicalein was determined by the MTT assay, and the effect on ZIKV infection determined by treating A549 cells with baicalien at different time points in the infection process. Parameters including level of infection, virus production, viral protein expression and genome copy number were assessed by flow cytometry, plaque assay, western blot and quantitative RT-PCR, respectively.

RESULTS

The results showed that baicalein had a half-maximal cytotoxic concentration (CC₅₀) of > 800 µM, and a half-maximal effective concentration (EC₅₀) of 124.88 µM. Time-of-addition analysis showed that baicalein had an inhibitory effect on ZIKV infection at the adsorption and post-adsorption stages. Moreover, baicalein also exerted a significant viral inactivation activity on ZIKV (as well as on dengue virus and Japanese encephalitis virus) virions.

CONCLUSION

Baicalein has now been shown to possess anti-ZIKV activity in a human cell line.

Baicalein prevents capecitabine-induced heart damage in female Wistar rats and enhances its anticancer potential in MCF-7 breast cancer cells

AIM

We investigated the ability of baicalein (BAI) to enhance the anticancer potential of capecitabine (CAP) in the MCF-7 cell line and its protective effect on CAP-induced cardiotoxicity in female Wistar rats.

METHODS AND KEY FINDINGS

In vitro study involved evaluating the effect of BAI and/or CAP on cell viability, cell cycle progression, and BAX and Bcl2 gene expression in MCF-7 cells. Co-treatment of BAI with CAP significantly reduced the viability of MCF-7 cells, improved their cytotoxic effect, markedly elevated the percentage of the sub-G1 population, drastically reduced the G2/M population, and significantly altered the mRNA expression of BAX and Bcl2 genes compared with each treatment alone. In vivo study revealed that the oral administration of CAP (140 mg/kg BW) to adult female rats significantly elevated the levels of serum creatine kinase-myocardial band (CK-MB), lactate dehydrogenase (LDH), tumor necrosis factor (TNF)-α, and interleukin (IL)-1β and cardiac TNF-α, IL-1β malondialdehyde (MDA) concentration, whereas it reduced the serum and cardiac total antioxidant capacity (TAC), level of cardiac glutathione (GSH) and activity of glutathione peroxidase (GPx) with a vast array of circulatory, inflammatory, degenerative, and necrotic alterations in the cardiac tissue. Furthermore, CAP administration significantly upregulated the mRNA expression of NF-κB, TLR4, MyD88, ATF6, CHOP, and JNK genes. Concurrent administration of BAI (200 mg/kg BW) and CAP significantly improved the biochemical alterations and cardiac oxidant/antioxidant status and architecture. In addition, it modulated the TLR4/MyD88/NF-κB pathway and endoplasmic reticulum stress.

SIGNIFICANCE

Altogether, BAI can augment the anticancer potential of CAP and alleviate its cardiotoxic effects during cancer treatment.

Baicalein alleviates TNF-α-induced apoptosis of human nucleus pulposus cells through PI3K/AKT signaling pathway

BACKGROUND

Nucleus pulposus (NP) cell apoptosis contributed to disc degeneration. Baicalein, a natural steroid saponin, has been demonstrated to have anti-inflammatory, antiapoptotic, and antioxidative effects in various diseases. However, little is known about the roles of baicalein in intervertebral disc degeneration.

METHODS

To evaluate the roles of baicalein in disc degeneration and its specific mechanism, human NP cells were incubated with TNF-α and various concentrations of baicalein. Cell viability, extracellular matrix protein expression, catabolic factors, degree of apoptosis, inflammatory factors, and related signaling pathways were evaluated by western blotting, fluorescence immunostaining, TUNEL staining, and reverse transcription PCR.

RESULTS

Baicalein inhibited TNF-α-activated apoptotic signaling and catabolic activity in NP cells. Baicalein promoted PI3K/Akt signaling and attenuated the level of apoptosis-related markers in TNF-α-stimulated human NP cells.

CONCLUSION

Our work provides that baicalein attenuates TNF-α-activated apoptosis in human NP cells through promoting the PI3K/Akt pathway, indicating that baicalein is a new potential candidate for clinical therapy to attenuate disc degeneration.

Fourier transform infrared spectroscopic markers of the scorching degree of Scutellariae Radix related to the variation patterns of flavonoids and carbohydrates

Scutellariae Radix (SR) is a common herb in Asia and Europe. In the clinical practice of traditional Chinese medicine, the raw SR is often stir-baked to partly scorch to reduce the side effects (stomach discomfort, diarrhea, etc.) but enhance some desired effects (such as the hemostatic activity). The scorching degree is crucial to assure the safety and efficacy of the scorched SR. Under-scorching is insufficient to adapt the adverse and favorable activities, while over-scorching can destroy all activities. Up to now, the scorching degree of SR is still determined by the manual observation of colors. Since the visual judgement is vulnerable to personal knowledge and experience, it is difficult to control the optimization and consistence of the scorching degree of SR. This research was designed to explore the potential indicators that can exactly reflect the scorching degree of SR and be measured objectively and quantitatively. A total of 15 morphological and chemical properties as well as Fourier transform infrared (FTIR) spectroscopy were included to profile the variations of the SR slices that were stir-baked at different temperatures for different times. According to the principal component analysis and statistical tests, 10 properties showed close relationships with the scorching degree of SR. As the increase of the heating time at the same heating temperature, the yield, L*, a*, b*, sucrose, baicalin and wogonoside decreased continuously and showed the monotone variation patterns. Meanwhile, 5-HMF, baicalein and wogonin showed the inflection variation patterns, which means these properties increased in the earlier stage but decreased in the later stage during the scorching process. FTIR spectra also revealed the variations of flavonoids and carbohydrates. The scorching degree of SR can be determined by the intuitive observation of FTIR spectral peaks at 1738 cm^-1, 1705 cm^-1, 1611 cm^-1, 1586 cm^-1, 1450 cm^-1, 1410 cm^-1 and 1023 cm^-1. In summary, FTIR spectroscopy can be used for the rapid assessment of the scorching degree of SR, while the contents of flavonoid glycosides and aglycones may be used as the quality criteria of the scorched SR.

Novel succinoglycan dialdehyde/aminoethylcarbamoyl-β-cyclodextrin hydrogels for pH-responsive delivery of hydrophobic drugs

β-Cyclodextrin cross-linked succinoglycan dialdehyde hydrogels was prepared for hydrophobic drug delivery. Succinoglycan dialdehyde (SGDA) was synthesized from sodium periodate oxidation of succinoglycan isolated from Sinorhizobium meliloti Rm1021. Aminoethylcarbamoyl-β-cyclodextrin (ACD) was crosslinked with SGDA to form a succinoglycan dialdehyde/aminoethylcarbamoyl-β-cyclodextrin (SGDA/ACD) hydrogels. The SGDA/ACD hydrogels exhibited a 65.7 % improvement in storage modulus (G') and a 5.7-fold higher compressive strain than the SGDA/poly(ethylene glycol) diamine (PEG) hydrogels as controls. A hardly soluble drug, baicalein was used for the drug loading and release properties of SGDA/ACD hydrogels. Baicalein was released about 98 % within 48 h at pH 7.4, but not completely released even after 48 h at pH 2.0. In addition, at pH 7.4, only about 56 % of the baicalein loaded on the SGDA/PEG hydrogels was released within 48 h, while about 98 % of the baicalein loaded on the SGDA/ACD hydrogels was released within 48 h. It indicates that ACD significantly improved the solubilization efficacy of the baicalein. In vitro testing of cell viability using HEK-293 cells also showed that the SGDA/ACD hydrogels were suitable for the cells. In conclusion, SGDA/ACD hydrogels significantly enhance the utilization of baicalein and provide potential applications in drug delivery systems for hardly soluble drugs.

Nano-baicalein facilitates chemotherapy in breast cancer by targeting tumor microenvironment

Cancer-associated fibroblasts constitute a significant component in the tumor microenvironment, playing a pivotal role in tumor proliferation, invasion, migration, and metastasis. Consequently, therapy combining chemotherapeutic agents with tumor microenvironment (TME) modulators appears to be a promising avenue for cancer treatment. In this paper, a tumor microenvironment-based mPEG-PLGA nanoparticle loaded with baicalein (PMs-Ba) was constructed for the purpose of improving the tumor microenvironment in cases of triple-negative breast cancer. The results demonstrate that, on the one hand, PMs-Ba was able to inhibit the transforming growth factor β(TGF-β) signaling pathway to avoid the activation of cancer-associated fibroblasts (CAFs), thereby influencing the interstitial microenvironment of the tumor. On the other hand, the agent led to an increase in the infiltration of cytotoxic T cells, activating the tumor immune microenvironment. Meanwhile, in the murine breast cancer model, an intravenous injection of PMs-Ba combined with doxorubicin nanoparticles (PMs-ADM) significantly improved the antitumor effectiveness. These results suggest that baicalein encapsulated in nanoparticles may be a promising strategy for modulating the TME and for adjuvant chemotherapy, signifying a potential TME-remodeling nanoformulation that could enhance the antitumor efficacy of nanotherapeutics.

Oxidation of baicalein by tyrosinase and by o-quinones

Baicalein (5,6,7-trihydroxyflavone) has been previously described as an inhibitor of tyrosinase (Guo et al. Int. J. Biol. Macromol. 118 (2018) 57-68). However, long before this article was published this flavonoid had been shown to be a substrate of this enzyme and a catecholic cofactor partially abolishing the lag-phase during oxidation of l-tyrosine. Other compounds with a 1,2,3-triphenol moiety, such as pyrogallol, gallic acid and its esters are also oxidized by tyrosinase. Gallic acid was also shown to reduce tyrosinase-generated o-quinones. We have demonstrated that baicalein is also rapidly oxidized by o-quinones generated from catechols by tyrosinase or by treatment with sodium periodate. Smaller changes of absorbance at 475 nm during oxidation of l-dopa by tyrosinase in the presence of baicalein do not result from enzyme inhibition but from reduction of dopaquinone by baicalein. This reaction prevents formation of dopachrome giving an effect of inhibition, which is only apparent. The actual reaction rates did not decrease but increased in the presence of baicalein, which we demonstrated by measurements of oxygen consumption.

Induction of DNMT1-dependent demethylation of SHP-1 by the natural flavonoid compound Baicalein overcame Imatinib-resistance in CML CD34+ cells

BACKGROUND

The most significant cause of treatment failure in chronic myeloid leukemia (CML) is a persistent population of minimal residual cells. Emerging evidences showed that methylation of SHP-1 contributed to Imatinib (IM) resistance. Baicalein was reported to have an effect on reversal of chemotherapeutic agents resistance. However, the molecular mechanism of Baicalein on JAK2/STAT5 signaling inhibition against drug resistance in bone marrow (BM) microenvironment that had not been clearly revealed.

METHODS

We co-cultured hBMSCs and CML CD34⁺ cells as a model of SFM-DR. Further researches were performed to clarify the reverse mechanisms of Baicalein on SFM-DR model and engraftment model. The apoptosis, cytotoxicity, proliferation, GM-CSF secretion, JAK2/STAT5 activity, the expression of SHP-1 and DNMT1 were analyzed. To validate the role of SHP-1 on the reversal effect of Baicalein, the SHP-1 gene was over-expressed by pCMV6-entry shp-1 and silenced by SHP-1 shRNA, respectively. Meanwhile, the DNMT1 inhibitor decitabine was used. The methylation extent of SHP-1 was evaluated using MSP and BSP. The molecular docking was replenished to further explore the binding possibility of Baicalein and DNMT1.

RESULTS

BCR/ABL-independent activation of JAK2/STAT5 signaling was involved in IM resistance in CML CD34⁺ subpopulation. Baicalein significantly reversed BM microenvironment-induced IM resistance not through reducing GM-CSF secretion, but interfering DNMT1 expression and activity. Baicalein induced DNMT1-mediated demethylation of the SHP-1 promoter region, and subsequently activated SHP-1 re-expression, which resulted in an inhibition of JAK2/STAT5 signaling in resistant CML CD34⁺ cells. Molecular docking model indicated that DNMT1 and Baicalein had binding pockets in 3D structures, which further supported Baicalein might be a small-molecule inhibitor targeting DNMT1.

CONCLUSIONS

The mechanism of Baicalein on improving the sensitivity of CD34⁺ cells to IM might be correlated with SHP-1 demethylation by inhibition of DNMT1 expression. These findings suggested that Baicalein could be a promising candidate by targeting DNMT1 to eradicate minimal residual disease in CML patients. Video Abstract.