New therapeutic aspects of flavones: the anticancer properties of Scutellaria and its main active constituents Wogonin, Baicalein and Baicalin

Identification and high-throughput quantification of baicalein and its metabolites in plasma and urine

ETHNOPHARMACOLOGICAL RELEVANCE

Scutellaria baicalensis Georgi. contains varieties of function compounds, and it has been used as traditional drug for centuries. Baicalein is the highest amount of flavonoid found in Scutellaria baicalensis Georgi., which exerts various pharmacological activities and might be a promising drug to treat COVID-19.

AIM OF THE STUDY

The present work aims to investigate the metabolism of baicalein in humans after oral administration, and study the pharmacokinetics of BA and its seven metabolites in plasma and urine.

MATERIALS AND METHODS

The metabolism profiling and the identification of baicalein metabolites were performed on HPLC-Q-TOF. Then a column-switching method named MPX™-2 system was applied for the high-throughput quantificationof BA and seven metabolites.

RESULTS

Seven metabolites were identified using HPLC-Q-TOF, including sulfate, glucuronide, glucoside, and methyl-conjugated metabolites. Pharmacokinetic study found that BA was extensively metabolized in vivo, and only 5.65% of the drug remained intact in the circulatory system after single dosing. Baicalein-7-O-sulfate and baicalein-6-O-glucuronide-7-O-glucuronide were the most abundant metabolites. About 7.2% of the drug was excreted through urine and mostly was metabolites.

CONCLUSION

Seven conjugated metabolites were identified in our assay. A high-throughput HPLC-MS/MS method using column switch was established for quantifying BA and its metabolites. The method has good sensitivity and reproducibility, and successfully applied for the clinical pharmacokinetic study of baicalein and identified metabolites. We expect that our results will provide a metabolic and pharmacokinetic foundation for the potential application of baicalein in medicine.

Baicalin-Loaded Lipid-Polymer Hybrid Nanoparticles Inhibiting the Proliferation of Human Colon Cancer: Pharmacokinetics and In Vivo Evaluation

This research work is focused on pharmacokinetic and biochemical experiments to assess baicalin-loaded lipid-polymer hybrid nanoparticles (LPHNPs) with colon-targeting specificity. The nanoprecipitation method was used to develop the LPHNPs, and the characterized formulation revealed the 184.3 nm particle size, PDI of 0.177, spherical shape, and zeta potential of -19.8 mV. The baicalin LPHNPs are said to be poorly absorbed in the stomach and small intestine, and in vitro drug release tests have shown that the drug is released mostly in the caecal fluid. Additionally, the LPHNPs showed stability and nonsignificant drug loss at 25 °C for 3 months. The least viable population of baicalin-loaded LPHNPs was detected at a lower IC₅₀ value after 48 h, and no cytotoxicity was observed by blank suspension and blank LPHNPs up to the concentration of 100 µg/mL. Apart from this, the pharmacokinetics study showed that baicalin from LPHNPs is much less absorbed and least available in the blood plasma and maximum available in the colon. Concurrently, organ distribution studies demonstrated that baicalin-loaded LPHNPs were distributed more widely in the colon compared to baicalin suspension. Moreover, baicalin-loaded LPHNPs were found to be superior to a baicalin suspension in reducing elevated liver enzyme levels. In a nutshell, baicalin-loaded LPHNPs show superior efficacy and can be maximally localized into the colon rectal cancer along with systemic availability of the drug.

Therapeutic Potential of Bioactive Components from Scutellaria baicalensis Georgi in Inflammatory Bowel Disease and Colorectal Cancer: A Review

Scutellaria baicalensis Georgi (SBG), an herbal medicine with various biological activities, including anti-inflammatory, anticancer, antiviral, antibacterial, and antioxidant activities, is effective in treatment of colitis, hepatitis, pneumonia, respiratory infections, and allergic diseases. This herbal medicine consists of major active substances, such as baicalin, baicalein, wogonoside, and wogonin. Inflammatory bowel disease (IBD) comprises a group of inflammatory conditions of the colon and small intestine, with Crohn's disease and ulcerative colitis being the main types. IBD can lead to serious complications, such as increased risk of colorectal cancer (CRC), one of the most common cancers worldwide. Currently, there is no cure for IBD, and its incidence has been increasing over the past few decades. This review comprehensively summarizes the efficacy of SBG in IBD and CRC and may serve as a reference for future research and development of drugs for IBD and cancer treatment.

Recent Advances in Pharmaceutical Cocrystals: A Focused Review of Flavonoid Cocrystals

Cocrystallization is currently an attractive technique for tailoring the physicochemical properties of active pharmaceutical ingredients (APIs). Flavonoids are a large class of natural products with a wide range of beneficial properties, including anticancer, anti-inflammatory, antiviral and antioxidant properties, which makes them extensively studied. In order to improve the properties of flavonoids, such as solubility and bioavailability, the formation of cocrystals may be a feasible strategy. This review discusses in detail the possible hydrogen bond sites in the structure of APIs and the hydrogen bonding networks in the cocrystal structures, which will be beneficial for the targeted synthesis of flavonoid cocrystals. In addition, some successful studies that favorably alter the physicochemical properties of APIs through cocrystallization with coformers are also highlighted here. In addition to improving the solubility and bioavailability of flavonoids in most cases, flavonoid cocrystals may also alter their other properties, such as anti-inflammatory activity and photoluminescence properties.

Stem Cells and Natural Agents in the Management of Neurodegenerative Diseases: A New Approach

Neurodegenerative diseases refer to a group of neurological disorders as a consequence of various destructive illnesses, that predominantly impact neurons in the central nervous system, resulting in impairments in certain brain functions. Alzheimer's disease, Parkinson's disease, Huntington's disease, multiple sclerosis, and other neurodegenerative disorders represent a major risk to human health. In order to optimize structural and functional recovery, reconstructive methods integrate many approaches now, to address the complex and multivariate pathophysiology of neurodegenerative disorders. Stem cells, with their unique property of regeneration, offer new possibilities in regenerative and reconstructive medicine. Concurrently, there is an important role for natural products in controlling many health sufferings and they can delay or even prevent the onset of various diseases. In addition, due to their therapeutic properties, they have been used as neuroprotective agents to treat neurodegenerative disorders. After decades of intensive research, scientists made advances in treating these disorders so far, but current therapies are still not capable of preventing the illnesses from progressing. Therefore, in this review, we focused on a new perspective combining stem cells and natural products as an innovative therapy option in the management of neurodegenerative diseases.

Baicalein activates 5' adenosine monophosphate-activated protein kinase, inhibits the mammalian target of rapamycin, and exhibits antiproliferative effects in pancreatic neuroendocrine tumors in vitro and in vivo

BACKGROUND

The mammalian target of rapamycin inhibition has been shown to prolong progression-free survival in patients with pancreatic neuroendocrine tumors. The natural compound baicalein indirectly inhibits the mammalian target of rapamycin, but it is unknown if baicalein exhibits such effects at physiologically achievable concentrations or exhibits synergy.

METHODS

Pancreatic neuroendocrine tumor cell lines were cultured with baicalein, everolimus, and/or a synthetic 5' adenosine monophosphate-activated protein kinase activating agent alone and in combination. Cell viability assays and immunoblotting were performed. Female severe combined immunodeficient-beige mice were injected with BON-1 cells and treated with baicalein and COH-SR4 solutions via oral gavage. Tumor volumes were compared at 30 days.

RESULTS

Immunoblotting revealed that treatment of baicalein induced 5' adenosine monophosphate-activated protein kinase activation and the mammalian target of rapamycin inhibition. Treatment with baicalein alone led to a significant decrease in the ratio of viable cells compared with controls at 72 hours at concentrations ≥5 μM (P = .021). The addition of COH-SR4 led to significantly greater effect on cell viability than with baicalein alone (P < .001, P < .001). The combination of baicalein with everolimus resulted in significantly lower cell viability than with everolimus alone (P = .005, P < .001). Tumor volume in vivo was significantly decreased with the combination of baicalein and COH-SR4 compared with controls (P = .003).

CONCLUSION

Baicalein exhibits antiproliferative effects against pancreatic neuroendocrine tumor cell lines at doses ≥5 μM and demonstrates synergy.

Baicalin-berberine complex nanocrystals orally promote the co-absorption of two components

Baicalin (BA)-berberine (BBR) have been proposed as the couple in the prevention and treatment of numerous diseases due to their multiple functional attributes. However, with regard to certain factors involving unsatisfactory aqueous solubility and low bioavailability associated with its clinical application, there is need for continuous researches by scientist. In this study, after successfully preparing BA-BBR complex, BA-BBR complex nanocrystals were obtained through high-pressure homogenization and evaluated (in vitro and in vivo). The particle size, distribution, morphology, and crystalline properties for the optimal BA-BBR complex nanocrystals were characterized by the use of scanning electron microscope, dynamic light scattering, powder X-ray diffraction, and differential scanning calorimetry. The particle size and poly-dispersity index of BA-BBR complex nanocrystals were 318.40 ± 3.32 nm and 0.26 ± 0.03, respectively. In addition, evaluation of the in vitro dissolution extent indicated that BA and BBR in BA-BBR complex nanocrystals were 3.30- and 2.35-fold than BA-BBR complex. Subsequently, single-pass intestinal perfusion combined with microdialysis test and oral pharmacokinetics in SD rats was employed to evaluate the in vivo absorption improvement of BA-BBR complex nanocrystals. The pharmacokinetics results exhibited that the area under curve of BA and BBR in the BA-BBR complex nanocrystals group were 622.65 ± 456.95 h·ng/ml and 167.28 ± 78.87 h·ng/ml, respectively, which were separately 7.49- and 2.64-fold than the complex coarse suspension. In conclusion, the above results indicate that the developed and optimized BA-BBR complex nanocrystals could improve the dissolution rate and extent and oral bioavailability, as well as facilitate the co-absorption of the drug prescriptions BA and BBR.

Crosstalk between xanthine oxidase (XO) inhibiting and cancer chemotherapeutic properties of comestible flavonoids- a comprehensive update

Gout is an inflammatory disease caused by metabolic disorder or genetic inheritance. People throughout the world are strongly dependent on ethnomedicine for the treatment of gout and some receive satisfactory curative treatment. The natural remedies as well as established drugs derived from natural sources or synthetically made exert their action by mechanisms that are closely associated with anticancer treatment mechanisms regarding inhibition of xanthine oxidase, feedback inhibition of de novo purine synthesis, depolymerization and disappearance of microtubule, inhibition of NF-ĸB activation, induction of TRAIL, promotion of apoptosis, and caspase activation and proteasome inhibition. Some anti-gout and anticancer novel compounds interact with same receptors for their action, e.g., colchicine and colchicine analogues. Dietary flavonoids, i.e., chrysin, kaempferol, quercetin, fisetin, pelargonidin, apigenin, luteolin, myricetin, isorhamnetin, phloretinetc etc. have comparable IC₅₀ values with established anti-gout drug and effective against both cancer and gout. Moreover, a noticeable number of newer anticancer compounds have already been isolated from plants that have been using by local traditional healers and herbal practitioners to treat gout. Therefore, the anti-gout plants might have greater potentiality to become selective candidates for screening of newer anticancer leads.

Post-Harvest Processing Methods Have Critical Roles in the Contents of Active Ingredients of Scutellaria baicalensis Georgi

To find the best post-harvest processing method for Scutellaria baicalensis Georgi, we explored the effects of fresh and traditional processing on the active ingredients in S. baicalensis and evaluated three drying techniques to determine the optimal post-harvest processing technique. We quantified four active ingredients (baicalin, baicalein, wogonoside, and wogonin) in 16 different processed S. baicalensis samples that were harvested from Tongchuan, Shaanxi province, by HPLC (high-performance liquid chromatography). In addition, we performed a similarity analysis (SA), a hierarchical cluster analysis (HCA), and a principal component analysis (PCA) on the common peaks in S. baicalensis that were identified by the HPLC fingerprints. Compared to the traditional processing method, the fresh processing method could better preserve the four active ingredients in S. baicalensis, meanwhile, the similarity analysis (0.997-1.000) showed that the fresh processing was more similar to the traditional processing, and it did not change the type of 18 active ingredients in S. baicalensis. The cluster analysis results showed that the shade drying and sun drying methods results were more similar to each other, while the oven drying (60 °C) method results were clustered into one category. According to the results of the principal component analysis, S9, S7, and S8 had higher scores, and they were relatively well processed under these processing settings. Fresh processing could be an alternative to traditional processing; the moisture content was reduced to 24.38% under the sun drying condition, and it was the optimal post-harvest processing solution for S. baicalensis.

Collection of Hairy Roots as a Basis for Fundamental and Applied Research

Due to population growth, instability of climatic conditions, and reduction of the areas of natural ecosystems, it becomes necessary to involve modern biotechnological approaches to obtain highly productive plant material. This statement applies both to the creation of plant varieties and the production of new pharmaceutical raw materials. Genetic transformation of valuable medicinal plants using Agrobacterium rhizogenes ensures the production of stable and rapidly growing hairy roots cultures that have a number of advantages compared with cell culture and, above all, can synthesize root-specific substances at the level of the roots of the intact plant. In this regard, special attention should be paid to the collection of hairy roots of the Institute of Plant Physiology RAS, Russian Academy of Sciences, the founder of which was Dr. Kuzovkina I.N. Currently, the collection contains 38 hairy roots lines of valuable medicinal and forage plants. The review discusses the prospects of creating a hairy roots collection as a basis for fundamental research and commercial purposes.

Promising natural products against SARS-CoV-2: Structure, function, and clinical trials

The corona virus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus type 2 (SARS-COV-2) poses a severe threat to human health and still spreads globally. Due to the high mutation ratio and breakthrough infection rate of the virus, vaccines and anti-COVID-19 drugs require continual improvements. Drug screening research has shown that some natural active products can target the critical proteins of SARS-CoV-2, including 3CLpro, ACE2, FURIN, and RdRp, which could produce great inhibitory effects on SARS-COV-2. In addition, some natural products have displayed activities of immunomodulation, antiinflammatory, and antihepatic failure in COVID-19 clinical trials, which may relate to their non-monomeric structures. However, further evaluation and high-quality assessments, including safety verification tests, drug interaction tests, and clinical trials, are needed to substantiate natural products' multi-target and multi-pathway effects on COVID-19. Here, we review the literature on several promising active natural products that may act as vaccine immune enhancers or provide targeted anti-COVID-19 drugs. The structures, mechanisms of action, and research progress of these natural products are analyzed, to hopefully provide effective ideas for the development of targeted drugs that possess better structure, potency, and safety.

Advances in Anti-Cancer Activities of Flavonoids in Scutellariae radix: Perspectives on Mechanism

Despite encouraging progresses in the development of novel therapies, cancer remains the dominant cause of disease-related mortality and has become a leading economic and healthcare burden worldwide. Scutellariae radix (SR, Huangqin in Chinese) is a common herb used in traditional Chinese medicine, with a long history in treating a series of symptoms resulting from cancer, like dysregulated immune response and metabolic abnormalities. As major bioactive ingredients extracted from SR, flavonoids, including baicalein, wogonin, along with their glycosides (baicalin and wogonoside), represent promising pharmacological and anti-tumor activities and deserve extensive research attention. Emerging evidence has made great strides in elucidating the multi-targeting therapeutic mechanisms and key signaling pathways underlying the efficacious potential of flavonoids derived from SR in the field of cancer treatment. In this current review, we aim to summarize the pharmacological actions of flavonoids against various cancers in vivo and in vitro. Moreover, we also make a brief summarization of the endeavor in developing a drug delivery system or structural modification to enhance the bioavailability and biological activities of flavonoid monomers. Taken together, flavonoid components in SR have great potential to be developed as adjuvant or even primary therapies for the clinical management of cancers and have a promising prospect.

Scutellaria baicalensis georgi is a promising candidate for the treatment of autoimmune diseases

Autoimmune diseases a group of disorders elicited by unexpected outcome of lymphocytes self-tolerance failure, and the common members of which include multiple sclerosis, systemic lupus erythematosus, inflammatory bowel disease, rheumatoid arthritis, and type 1 diabetes mellitus, etc. The pathogenesis of autoimmune diseases is not fully understood and the current therapeutic regimen’s inefficacy in certain cases coupled with low rates of success, exorbitant financial burden, as well as numerous side effects, which do open new avenues for the role of natural products as novel therapeutic agents for auto-inflammatory disorders. Scutellaria baicalensis Georgi is a well-known and widely-recognized herbal medicine with certain ameliorative effect on diverse inflammation-involved dysfunction. Though recent advances do highlight its potential to be applied in the fight against autoimmune diseases, the specific mechanism and the related opinion on the exploring possibility are still limited which hampered the further progress. Here in this timeline review, we traced and collected the evidence of how Scutellaria baicalensis Georgi and its bioactive contents, namely baicalin, baicalein, wogonoside and wogonin affect autoimmune diseases. Moreover, we also discussed the clinical implications and therapeutic potential of Scutellaria baicalensis Georgi and its bioactive contents in autoimmune diseases treatment.

Baicalein Induces Apoptosis of Rheumatoid Arthritis Synovial Fibroblasts through Inactivation of the PI3K/Akt/mTOR Pathway

Purpose

Rheumatoid arthritis (RA) shows abnormal proliferation, apoptosis, and invasion in fibroblast-like synoviocytes (FLSs). Baicalein (BAI), extracted from Scutellaria baicalensis, is used as an anticancer drug through inducing cancer cells apoptosis. However, the mechanism of BAI in RA progression still remains unknown. Here, we demonstrated that BAI inhibited FLS proliferation and migration, whereas it enhanced apoptosis via the PI3K/Akt/mTOR pathway in vitro.

Methods

Cell viability and colony formation were analyzed by MTT and plate colony formation assays in SW982 cells, respectively. Apoptosis was detected by flow cytometry and western blotting. Epithelial-mesenchymal transition (EMT), MMP family proteins (MMP2/9), and the PI3K/Akt/mTOR pathway were detected by western blot. Cell migration was detected by scratch healing assay under BAI treatment in SW982 cells.

Results

BAI dose-dependently inhibited cell viability and colony forming in SW982 cells. BAI upregulated apoptotic proteins and downregulated EMT-related proteins, resulting in enhanced cell apoptosis and inhibited cell migration in SW982 cells. BAI also dose-dependently inhibited the phosphorylation of PI3K, Akt, and mTOR.

Conclusions

These results indicated that BAI inhibited FLSs proliferation and EMT, whereas induced cell apoptosis through blocking the PI3K/Akt/mTOR pathway, supporting clinical application for RA progression.

How does UV-B stress affect secondary metabolites of Scutellaria baicalensis in vitro shoots grown at different 6-benzyl aminopurine concentrations?

Ultraviolet-B (UV-B) radiation is one of the abiotic stresses that can significantly affect the secondary metabolite accumulation in in vitro tissue cultures of medicinal plants. The present study investigated the effects of UV-B radiation on the secondary metabolites and antioxidant activities of Scutellaria baicalensis in vitro shoots grown at different concentrations of 6-benzyl aminopurine (6-BA), which is the cytokinin most widely used in plant tissue culture. The UV-B radiation caused significant increases in lipid peroxidation, total phenolic, and flavonoid contents, and antioxidant activities in the in vitro shoots grown at lower 6-BA concentrations (0 and 1 mg L^-1 ), while it did not cause any significant changes in those grown at higher 6-BA concentrations (2 and 3 mg L^-1 ). However, the UV-B radiation significantly altered the contents of main individual flavonoids at both lower and higher 6-BA concentrations. Upon UV-B radiation, aglycones (including baicalein, wogonin, and scutellarein) increased, while glucuronides such as baicalin and wogonoside decreased; this was more evident at higher 6-BA concentrations. This study demonstrated that the effects of UV-B radiation on the secondary metabolites of S. baicalensis in vitro shoots highly depended on the 6-BA concentration in the culture medium.

Effects of Origanum vulgare and Scutellaria baicalensis on the Physiological Activity and Biochemical Parameters of the Blood in Rats on a High-Fat Diet

The pharmacological effects of medicinal plants play a primary role in the mild correction of body weight in humans and animals, reducing the accumulation of fat in their bodies during a state of obesity. Origanum vulgare L. and Scutellaria baicalensis Georgi are widely used as food additives and medicinal plants, but their comprehensive physiological evaluation in model animals in a state of obesity has not been carried out. In a 30-day laboratory experiment on male rats which had developed obesity through a hypercaloric diet, the effects of adding the dry crushed grass O. vulgare or dry crushed roots of S. baicalensis to their feed was evaluated. During the experiment, the rats fed with O. vulgare increased in body weight to only 105.5% of their initial weight, while the body weight of the control group increased to 111.5%, and that of animals fed on S. baicalensis increased to 124.0% of their initial body weight. The average daily increase in the rats’ body weight when O. vulgare was added to their diet decreased to 205 mg/day, and when S. baicalensis was added, on the contrary, it increased to 1417 mg/day, compared to 700 mg/day among the control group. Under the influence of O. vulgare, the lipid metabolism of the rats normalized: the atherogenic index decreased to 33.7%, compared with the values of the control group, due to an increase in the concentration of high-density lipoproteins from cholesterol. The concentration of triglycerides decreased, and the concentration of glucose decreased. The roots of S. baicalensis being added into the diet of rats increased the activity of alkaline phosphatase and decreased the concentration of urea. The atherogenic index also decreased (by up to 35.5% in the control group) and the concentration of high-density lipoprotein cholesterol increased, while the concentrations of triglycerides and glucose decreased. The physical activity of the rats showed a slight tendency to decrease when both O. vulgare and S. baicalensis were added to their diet. Both plant species contributed to a decrease in the emotional status of animals, which was most pronounced when the O. vulgare grass was added to the feed. The results of the study demonstrate the potential of the use of O. vulgare and S. baicalensis as herbal supplementations for the correction of hyperlipidemia and type-2 diabetes mellitus in overweight patients.

Activating caspase-8/Bid/ROS signaling to promote apoptosis of breast cancer cells by folate-modified albumin baicalin-loaded nanoparticles

Abnormal apoptosis can lead to uncontrolled cell growth, aberrant homeostasis or the accumulation of mutations. Therapeutic agents that re-establish the normal functions of apoptotic signaling pathways offer an attractive strategy for the treatment of breast cancer. Baicalin (BA) is one of the natural compounds with anti-proliferation and pro-apoptosis activities against numerous tumor cells. However, low bioavailability restricts the clinical application of BA. In order to improve its therapeutic efficacy and study the mechanism of actions, active targeting delivery systems were developed for targeting tumor environment and selective cell killing effects. It emphasized on the construction of folate-conjugated albumin nanoparticles loaded with baicalin (FA-BSANPs/BA) and mechanisms of which on the promotion of breast cancer apoptosis. The physicochemical properties and structural characteristics of FA-BSANPs/BA were investigated. Cell experiments were carried out to study the targeted anti-breast cancer effects of FA-BSANPs/BA and its mechanism. The results showed that FA-BSANPs/BA was successfully constructed with stable structural characteristics and sustained release effects. Cellular uptake and MTT showed that it increased targeted uptake efficiency and cytotoxicity. Flow cytometry and western blot confirmed that it promoted apoptosis by increasing the expression of caspase-8 and ROS, and decreasing the level of Bid. It is suggested that the pro-apoptotic mechanism of FA-BSANPs/BA is related to regulation of key proteins in extrinsic apoptotic pathway. In conclusion, FA-BSANPs/BA is a good delivery carrier and significantly inhibits the breast cancer growth compared with free BA. The mechanism of FA-BSANPs/BA promoting apoptosis of breast cancer may be due to its action on the caspase-8/Bid/ROS pathway.

Protective and therapeutic effects of Scutellaria baicalensis and its main active ingredients baicalin and baicalein against natural toxicities and physical hazards: a review of mechanisms

OBJECTIVES

Scutellaria baicalensis (SB) has been traditionally used to combat a variety of conditions ranging from ischemic heart disease to cancer. The protective effects of SB are due to the action of two main flavonoids baicalin (BA) and baicalein (BE). This paper aimed to provide a narrative review of the protective and antidotal effects of SB and its main constituents against natural toxicities and physical hazards.

EVIDENCE ACQUISITION

Scientific databases Medline, Scopus, and Web of Science were thoroughly searched, based on different keywords for in vivo, in vitro and clinical studies which reported protective or therapeutic effects of SB or its constituents in natural and physical toxicities.

RESULTS

Numerous studies have reported that treatment with BE, BA, or total SB extract prevents or counteracts the detrimental toxic effects of various natural compounds and physical hazards. The toxic agents include mycotoxins, lipopolysaccharide, multiple plants and animal-derived substances as well as physical factors which negatively affected vital organs such as CNS, liver, kidneys, lung and heart. Increasing the expression of radical scavenging enzymes and glutathione content as well as inhibition of pro-inflammatory cytokines and pro-apoptotic mediators were important mechanisms of action.

CONCLUSION

Different studies on the Chinese skullcap have exhibited that its total root extract, BA or BE can act as potential antidotes or protective agents against the damage induced by natural toxins and physical factors by alleviating oxidative stress and inflammation. However, the scarcity of high-quality clinical evidence means that further clinical studies are required to reach a more definitive conclusion.

Role of baicalin as a potential therapeutic agent in hepatobiliary and gastrointestinal disorders: A review

Baicalin is a natural bioactive compound derived from Scutellaria baicalensis, which is extensively used in traditional Chinese medicine. A literature survey demonstrated the broad spectrum of health benefits of baicalin such as antioxidant, anticancer, anti-inflammatory, antimicrobial, cardio-protective, hepatoprotective, renal protective, and neuroprotective properties. Baicalin is hydrolyzed to its metabolite baicalein by the action of gut microbiota, which is further reconverted to baicalin via phase 2 metabolism in the liver. Many studies have suggested that baicalin exhibits therapeutic potential against several types of hepatic disorders including hepatic fibrosis, xenobiotic-induced liver injury, fatty liver disease, viral hepatitis, cholestasis, ulcerative colitis, hepatocellular and colorectal cancer. During in vitro and in vivo examinations, it has been observed that baicalin showed a protective role against liver and gut-associated abnormalities by modifying several signaling pathways such as nuclear factor-kappa B, transforming growth factor beta 1/SMAD3, sirtuin 1, p38/mitogen-activated protein kinase/Janus kinase, and calcium/calmodulin-dependent protein kinase kinaseβ/adenosine monophosphate-activated protein kinase/acetyl-coenzyme A carboxylase pathways. Furthermore, baicalin also regulates the expression of fibrotic genes such as smooth muscle actin, connective tissue growth factor, β-catenin, and inflammatory cytokines such as interferon gamma, interleukin-6 (IL-6), tumor necrosis factor-alpha, and IL-1β, and attenuates the production of apoptotic proteins such as caspase-3, caspase-9 and B-cell lymphoma 2. However, due to its low solubility and poor bioavailability, widespread therapeutic applications of baicalin still remain a challenge. This review summarized the hepatic and gastrointestinal protective attributes of baicalin with an emphasis on the molecular mechanisms that regulate the interaction of baicalin with the gut microbiota.

Phytochemical Profiling and Bio-Potentiality of Genus Scutellaria: Biomedical Approach

Scutellaria (Lamiaceae) comprises over 360 species. Based on its morphological structure of calyx, also known as Skullcap, it is herbaceous by habit and cosmopolitan by habitat. The species of Scutellaria are widely used in local communities as a natural remedy. The genus contributed over three hundred bioactive compounds mainly represented by flavonoids and phenols, chemical ingredients which serve as potential candidates for the therapy of various biological activities. Thus, the current review is an attempt to highlight the biological significance and its correlation to various isolated bioactive ingredients including flavonoids, terpenoids, phenols, alkaloids, and steroids. However, flavonoids were the dominant group observed. The findings of the Scutellaria reveal that due to its affluent basis of numerous chemical ingredients it has a diverse range of pharmacological potentials, such as antimicrobial, antioxidant, antifeedant, enzyme inhibition, anti-inflammatory, and analgesic significance. Currently, various bioactive ingredients have been investigated for various biological activities from the genus Scutellaria in vitro and in vivo. Furthermore, these data help us to highlight its biomedical application and to isolate the responsible compounds to produce innovative medications as an alternative to synthetic drugs.

Mechanistic Effects of Baicalein on Aqueous Humor Drainage and Intraocular Pressure

Elevated intraocular pressure (IOP) is a major risk factor for glaucoma that results from impeded fluid drainage. The increase in outflow resistance is caused by trabecular meshwork (TM) cell dysfunction and excessive extracellular matrix (ECM) deposition. Baicalein (Ba) is a natural flavonoid and has been shown to regulate cell contraction, fluid secretion, and ECM remodeling in various cell types, suggesting the potential significance of regulating outflow resistance and IOP. We demonstrated that Ba significantly lowered the IOP by about 5 mmHg in living mice. Consistent with that, Ba increased the outflow facility by up to 90% in enucleated mouse eyes. The effects of Ba on cell volume regulation and contractility were examined in primary human TM (hTM) cells. We found that Ba (1–100 µM) had no effect on cell volume under iso-osmotic conditions but inhibited the regulatory volume decrease (RVD) by up to 70% under hypotonic challenge. In addition, Ba relaxed hTM cells via reduced myosin light chain (MLC) phosphorylation. Using iTRAQ-based quantitative proteomics, 47 proteins were significantly regulated in hTM cells after a 3-h Ba treatment. Ba significantly increased the expression of cathepsin B by 1.51-fold and downregulated the expression of D-dopachrome decarboxylase and pre-B-cell leukemia transcription factor-interacting protein 1 with a fold-change of 0.58 and 0.40, respectively. We suggest that a Ba-mediated increase in outflow facility is triggered by cell relaxation via MLC phosphorylation along with inhibiting RVD in hTM cells. The Ba-mediated changes in protein expression support the notion of altered ECM homeostasis, potentially contributing to a reduction of outflow resistance and thereby IOP.

Baicalein Prevents Fructose-Induced Hepatic Steatosis in Rats: In the Regulation of Fatty Acid De Novo Synthesis, Fatty Acid Elongation and Fatty Acid Oxidation

Non-alcoholic fatty liver disease (NAFLD), ranging from simple steatosis to non-alcoholic steatohepatitis (NASH), hepatic fibrosis and even hepatocellular carcinoma, is a liver disease worldwide without approved therapeutic drugs. Baicalein (BAL), a flavonoid compound extracted from the Traditional Chinese Medicine (TCM) Scutellariae Radix (Scutellaria baicalensis Georgi.), has been used in TCM clinical practice for thousands of years to treat liver diseases due to its "hepatoprotective effect". However, the underlying liver-protecting mechanisms remain largely unknown. Here, we found that oral administration of BAL significantly decreased excess serum levels of triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), aspartate aminotransferase (AST) as well as hepatic TG in fructose-fed rats. Attenuation of the increased vacuolization and Oil Red O staining area was evident on hepatic histological examination in BAL-treated rats. Mechanistically, results of RNA-sequencing, western-blot, real-time quantitative PCR (RT-qPCR) and hepatic metabolomics analyses indicated that BAL decreased fructose-induced excessive nuclear expressions of mature sterol regulatory element-binding protein 1c (mSREBP1c) and carbohydrate response element-binding protein (ChREBP), which led to the decline of lipogenic molecules [including fatty acid synthase (FASN), stearoyl-CoA desaturase 1 (SCD1), elongation of very long chain fatty acids 6 (ELOVL6), acetyl-CoA carboxylase (ACC)], accompanying with the alternation of hepatic fatty acids composition. Meanwhile, BAL enhanced fatty acid oxidation by activating AMPK/PGC1α signaling axis and PPARα signal pathway, which elicited high expression of carnitine palmitoyl transferase 1α (CPT1α) and Acyl-CoA oxidase 1 (ACO1) in livers of fructose-fed rats, respectively. BAL ameliorated fructose-induced hepatic steatosis, which is associated with regulating fatty acid synthesis, elongation and oxidation.

Polyphenols for the Treatment of Ischemic Stroke: New Applications and Insights

Ischemic stroke (IS) is a leading cause of death and disability worldwide. Currently, the main therapeutic strategy involves the use of intravenous thrombolysis to restore cerebral blood flow to prevent the transition of the penumbra to the infarct core. However, due to various limitations and complications, including the narrow time window in which this approach is effective, less than 10% of patients benefit from such therapy. Thus, there is an urgent need for alternative therapeutic strategies, with neuroprotection against the ischemic cascade response after IS being one of the most promising options. In the past few decades, polyphenolic compounds have shown great potential in animal models of IS because of their high biocompatibility and ability to target multiple ischemic cascade signaling pathways, although low bioavailability is an issue that limits the applications of several polyphenols. Here, we review the pathophysiological changes following cerebral ischemia and summarize the research progress regarding the applications of polyphenolic compounds in the treatment of IS over the past 5 years. Furthermore, we discuss several potential strategies for improving the bioavailability of polyphenolic compounds as well as some essential issues that remain to be addressed for the translation of the related therapies to the clinic.

Natural Products and their Derivatives as Immune Check Point Inhibitors: Targeting Cytokine/Chemokine Signalling in Cancer

Cancer immunotherapy is the new generation and widely accepted form of tumour treatment. It is, however, associated with exclusive challenges which include organ-specific inflammation, and single-target strategies. Therefore, approaches that can enhance the efficiency of existing immunotherapies and expand their indications are required for the further development of immunotherapy. Natural products and medicines are stated to have this desired effect on cancer immunotherapy (adoptive immune-cells therapy, cancer vaccines, and immune-check point inhibitors). They refurbish the immunosuppressed tumour microenvironment, which is the primary location of interaction of tumour cells with the host immune system. Various immune cell subsets, via interaction with cytokine/chemokine receptors, are recruited into this microenvironment, and these subsets have roles in tumour progression and treatment responsiveness. This review summarises cytokine/chemokine signalling, types of cancer immunotherapy and the herbal medicine-derived natural products targeting cytokine/chemokines and immune checkpoints. These natural compounds possess immunomodulatory activities and exert their anti-tumour effect by either blocking the interaction or modulating the expression of the proteins linked with immune checkpoint signaling pathways. Some compounds also show a synergistic effect in combination with existing monoclonal antibody drugs to reverse the tumour microenvironment. Additionally, we have also reported some studies about the derivatives and formulations used to overcome the limitations of natural forms. This review can provide important insights for directing future research.

Scutellaria baicalensis and its constituents baicalin and baicalein as antidotes or protective agents against chemical toxicities: a comprehensive review

Scutellaria baicalensis (SB), also known as the Chinese skullcap, has a long history of being used in Chinese medicine to treat a variety of conditions ranging from microbial infections to metabolic syndrome and malignancies. Numerous studies have reported that treatment with total SB extract or two main flavonoids found in its root and leaves, baicalin (BA) and baicalein (BE), can prevent or alleviate the detrimental toxic effects of exposure to various chemical compounds. It has been shown that BA and BE are generally behind the protective effects of SB against toxicants. This paper aimed to review the protective and therapeutic effects of SB and its main components BA and BE against chemical compounds that can cause intoxication after acute or chronic exposure and seriously affect different vital organs including the brain, heart, liver, and kidneys. In this review paper, we had a look into a total of 221 in vitro and in vivo studies from 1995 to 2021 from the scientific databases PubMed, Scopus, and Web of Science which reported protective or therapeutic effects of BA, BE, or SB against drugs and chemicals that one might be exposed to on a professional or accidental basis and compounds that are primarily used to simulate disease models. In conclusion, the protective effects of SB and its flavonoids can be mainly attributed to increase in antioxidants enzymes, inhibition of lipid peroxidation, reduction of inflammatory cytokines, and suppression of apoptosis pathway.

Antitumor Potential of Immunomodulatory Natural Products

Cancer is one of the leading causes of death globally. Anticancer drugs aim to block tumor growth by killing cancerous cells in order to prevent tumor progression and metastasis. Efficient anticancer drugs should also minimize general toxicity towards organs and healthy cells. Tumor growth can also be successfully restrained by targeting and modulating immune response. Cancer immunotherapy is assuming a growing relevance in the fight against cancer and has recently aroused much interest for its wider safety and the capability to complement conventional chemotherapeutic approaches. Natural products are a traditional source of molecules with relevant potential in the pharmacological field. The huge structural diversity of metabolites with low molecular weight (small molecules) from terrestrial and marine organisms has provided lead compounds for the discovery of many modern anticancer drugs. Many natural products combine chemo-protective and immunomodulant activity, thus offering the potential to be used alone or in association with conventional cancer therapy. In this review, we report the natural products known to possess antitumor properties by interaction with immune system, as well as discuss the possible immunomodulatory mechanisms of these molecules.

Antioxidant potential and molecular docking of bioactive compound of Camellia sinensis and Camellia assamica with cytochrome P450

Camellia sinensis and Camellia assamica are well known for their medicinal and therapeutic potential. The purpose of this work is to assess the flavonoid content and antioxidant potential of methanol extracts of C. sinensis (MES) and acetone extract of C. assamica (AEA) experimentally and computationally. Qualitative analysis was done to assess the presence of flavonoids. Further, the antioxidant potential of MES and AEA was done by ABTS (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid)) and superoxide free radical-scavenging activity. The profiling of functional groups was analyzed by FT-IR analysis. The bioactive compounds n-heptadecanol-1 of MES and 2',6'-dihydroxyacetophenone, bis(trimethylsilyl) ether of AEA were procured from our previous study to analyze their antioxidant potential computationally (Auto-dock Vina). Both the extracts showed their potential to neutralize free radicals with variable potency. The study of the molecular interactions revealed that both the extracts MES and AEA interacted to the active site with higher binding energy. This work deduced that n-heptadecanol-1 and 2',6'-dihydroxyacetophenone, bis(trimethylsilyl) ether have good potential to inhibit and scavenge the free radicals.

A Review of Twenty Years of Research on the Regulation of Signaling Pathways by Natural Products in Breast Cancer

Breast cancer (BC) is the second leading cause of death among women, and it has become a global health issue due to the increasing number of cases. Different treatment options, including radiotherapy, surgery, chemotherapy and anti-estrogen therapy, aromatase inhibitors, anti-angiogenesis drugs, and anthracyclines, are available for BC treatment. However, due to its high occurrence and disease progression, effective therapeutic options for metastatic BC are still lacking. Considering this scenario, there is an urgent need for an effective therapeutic strategy to meet the current challenges of BC. Natural products have been screened as anticancer agents as they are cost-effective, possess low toxicity and fewer side effects, and are considered alternative therapeutic options for BC therapy. Natural products showed anticancer activities against BC through the inhibition of angiogenesis, cell migrations, proliferations, and tumor growth; cell cycle arrest by inducing apoptosis and cell death, the downstream regulation of signaling pathways (such as Notch, NF-κB, PI3K/Akt/mTOR, MAPK/ERK, and NFAT-MDM2), and the regulation of EMT processes. Natural products also acted synergistically to overcome the drug resistance issue, thus improving their efficacy as an emerging therapeutic option for BC therapy. This review focused on the emerging roles of novel natural products and derived bioactive compounds as therapeutic agents against BC. The present review also discussed the mechanism of action through signaling pathways and the synergistic approach of natural compounds to improve their efficacy. We discussed the recent in vivo and in vitro studies for exploring the overexpression of oncogenes in the case of BC and the current status of newly discovered natural products in clinical investigations.

Baicalein: A review on its anti-cancer effects and mechanisms in lung carcinoma

Plant-derived flavonoids are reported to function as potential anti-cancer agents against different types of cancer. Baicalein (BE) is an important flavonoid found in the roots of Scutellaria baicalensis that is popularly used in Chinese medicine as an ingredient in herbal tea preparations to promote wellness. BE has been studied for its several biological effects including antioxidant, anti-inflammatory, anti-hepatotoxic, antiviral, and anti-tumor properties. BE has now been discovered to be an effective agent against lung neoplasm. The molecular factors supporting baicalein's anti-cancer activity against lung cancer and its value to human health are discussed in this article. This would help in identifying BE as a promising competent drug against lung carcinoma. PRACTICAL APPLICATIONS: Baicalein is a flavonoid obtained from the roots of Scutellaria baicalensis. It has been widely used as an antioxidant, anti-inflam5matory, anti-hepatotoxic, antiviral, and anti-cancer agent. Lung cancer is one of the most common malignancies in the world with a high fatality rate. Several studies have found that Baicalein is an important candidate for treating lung cancer. Its mechanism of action includes regulation of cell proliferation, metastasis, apoptosis, autophagy, and so on. Baicalein could be used as a novel anti-cancer drug for the treatment of lung carcinoma.

Design, synthesis, and biological evaluation of C-8 modified curcumol derivatives against colorectal cancer cell lines

A series of structurally modified curcumol derivatives at C-8 position were designed and synthesized, whose structures were confirmed by 1H NMR,13C NMR, and HRMS analysis. The tested compounds were evaluated for in vitro antitumor activity against colorectal cancer cell lines SW620, HCT116, and CaCo2. Many of the tested candidates exhibited higher inhibition efficiency than curcumol. Among them, compound 3 l shows the best inhibitory effect on the viability of SW620 with IC50 value of 19.90 ± 0.64 µM. The structure-activity relationships of these derivatives were discussed, which showed that the introduction of amino or aryl groups tended to increase the anti-cancer activity. In addition, compound 3 l may inhibit cancer cell proliferation through triggering cell apoptosis.

Drug Candidates for Autoimmune Diseases

Most of the immunosuppressive drugs used in the clinic to prevent organ rejection or to treat autoimmune disorders were originally isolated from fungi or bacteria. Therefore, in addition to plants, these are valuable sources for identification of new potent drugs. Many side effects of established drugs limit their usage and make the identification of new immunosuppressants necessary. In this review, we present a comprehensive overview of natural products with potent anti-inflammatory activities that have been tested successfully in different models of chronic inflammatory autoimmune diseases. Some of these candidates already have passed first clinical trials. The anti-inflammatory potency of these natural products was often comparable to those of established drugs, and they could be used at least in addition to standard therapy to reduce their dose to minimize unwanted side effects. A frequent mode of action is the inhibition of classical inflammatory signaling pathways, such as NF-κB, in combination with downregulation of oxidative stress. A drawback for the therapeutic use of those natural products is their moderate bioavailability, which can be optimized by chemical modifications and, in addition, further safety studies are necessary. Altogether, very interesting candidate compounds exist which have the potential to serve as starting points for the development of new immunosuppressive drugs.

Baicalein Ameliorates Myocardial Ischemia Through Reduction of Oxidative Stress, Inflammation and Apoptosis via TLR4/MyD88/MAPKS/NF-κB Pathway and Regulation of Ca2+ Homeostasis by L-type Ca2+ Channels

Background: Baicalein (Bai) is the principal ingredient of Scutellaria baicalensis Georgi. Reports concerning the therapeutic advantages in treating cardiovascular diseases have been published. However, its protective mechanism towards myocardial ischemia (MI) is undefined.

Objective: The aim of this study was to investigate the protective mechanisms of Bai on mouse and rat models of MI.

Methods: Mice were pre-treated with Bai (30 and 60 mg/kg/day) for 7 days followed by subcutaneous injections of isoproterenol (ISO, 85 mg/kg/day) for 2 days to establish the MI model. Electrocardiograms were recorded and serum was used to detect creatine kinase (CK), lactate dehydrogenase (LDH), superoxide dismutase (SOD), catalase (CAT), glutathione (GSH) and malondialdehyde (MDA). Cardiac tissues were used to detect Ca²⁺ concentration, morphological pathologies, reactive oxygen species (ROS), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α). In addition, the expression levels of Bcl-2-associated X (Bax), B cell lymphoma-2 (Bcl-2), Caspase-3, Toll-like receptor-4 (TLR4), myeloid differentiation protein 88 (MyD88), nuclear factor-kappa B (NF-κB), p-p38, p-extracellular signal-regulated kinase1/2 (p-ERK1/2) and c-Jun N-terminal kinase (p-JNK) were assessed by western blots in myocardial tissues. The effects of Bai on L-type Ca²⁺ currents (I_Ca-L), contractility and Ca²⁺ transients in rat isolated cardiomyocytes were monitored by using patch clamp technique and IonOptix system. Moreover, ISO-induced H9c2 myocardial injury was used to detect levels of inflammation and apoptosis.

Results: Bai caused an improvement in heart rate, ST-segment and heart coefficients. Moreover, Bai led to a reduction in CK, LDH and Ca²⁺ concentrations and improved morphological pathologies. Bai inhibited ROS generation and reinstated SOD, CAT and GSH activities in addition to inhibition of replenishing MDA content. Also, expressions of IL-6 and TNF-α in addition to Bax and Caspase-3 were suppressed, while Bcl-2 expression was upregulated. Bai inhibited protein expressions of TLR4/MyD88/MAPK_S/NF-κB and significantly inhibited I_Ca-L, myocyte contraction and Ca²⁺ transients. Furthermore, Bai caused a reduction in inflammation and apoptosis in H9c2 cells.

Conclusions: Bai demonstrated ameliorative actions towards MI, which might have been related to attenuation of oxidative stress, inflammation and apoptosis via suppression of TLR4/MyD88/MAPK_S/NF-κB pathway and adjustment of Ca²⁺ homeostasis via L-type Ca²⁺ channels.

Baicalein inhibits cell proliferation and enhances apoptosis in human A549 cells and benzo(a)pyrene-induced pulmonary carcinogenesis in mice

Our current study is done to explore the possible mechanisms to elaborate on the growth inhibitory effect of baicalein (BE) in human lung carcinoma. Initially, BE (25 and 50 µM) treatment for 24 h, suppressed the viability and inhibited population growth in A549 cells. BE upholds the production of reactive oxygen species (ROS) with concomitant replenishment of glutathione, catalase, and glutathione peroxidase activity. The expression level of nuclear factor erythroid 2-related factor 2 and heme oxygenase-1 markedly increased after BE treatment will intimidate A549 cells proliferation by the ROS-independent pathway via the antioxidant pathway. In vivo investigations were carried out on BE (12 mg/kg, oral) in benzo(a)pyrene (B(a)P; 50 mg/kg, oral) induced lung carcinogenesis in mice. BE induces caspase-dependent apoptosis by increasing the levels of cytosolic cytochrome c accompanied by upregulating the outflow of p53, Bax, and caspase-3 with a concomitant abatement in the outflow of Bcl-2 in both in vitro and in vivo. In the murine model, BE treatment hindered the countenance of proliferation-related proteins (argyrophilic nucleolar organizing regions and proliferating cell nuclear antigen). Additionally, appraisal of the cell nucleus by transmission electron microscopic assessment uncovered that BE treatment adequately counteracts B(a)P-induced lung cancer cell survival. During the transition of the G₀ /G₁ phase, BE is arrested in the cell cycle process. This might be the cause of a substantial increase in the appearance of p21^Cip1 with concomitant downregulating the expressions of CDK4, cyclin D, and cyclin E both in vitro and in vivo. Our results conclude that BE treatment induced apoptosis and repressed proliferation both in vitro and in vivo of human lung carcinoma.

Interaction Properties of Biosynthesized Cadmium Sulphide Quantum Dots with Human Serum Albumin: Further Investigation of Antibacterial Activities and Sensing Applications

Synthesis of low dimensional quantum dots (QDs) (1-10 nm) via green route has garnered great interest having the prospective use in many biological applications (diagnosis, drug delivery and in vivo sensing), which is difficult to achieve by chemical synthesize methods having larger QDs particles or hazardous reagents required for synthesizing of QDs. Here, we have synthesized biogenic cadmium sulphide (CdS) QDs using green tea extract as reducing agents that were homogeneous and smaller size particles 2-4 nm. We also elucidate the (a) protein binding, (b) antibacterial and (c) sensing applications of biogenic CdS QDs in this present work. The biosynthesized CdS QDs were found to have extensive antibacterial activity against both gram-negative E. coli and gram-positive E. faecalis bacterial strains. Since the introduction of QDs in biological media, they can form protein-QDs complex; hence we investigate the binding interaction of CdS QDs with the carrier protein human serum albumin (HSA) in vitro. The synthesized CdS QDs quenched the intrinsic fluorescence of HSA through static quenching mechanism and binding constant (K_b ) was found in order of 10⁴ M^-1 . It was also observed that presence of biogenic CdS QDs affects the HSA-ligand interactions in vitro. The synthesized CdS showed highly effective sensors for tetracycline, rifampicin and bilirubin with LOD values of 99, 141 and 29 ng/mL respectively.

Medicinal Plants in Cancer Treatment: Contribution of Nuclear Factor-Kappa B (NF-kB) Inhibitors

Nuclear factor-kappa B (NF-κB) is one of the principal inducible proteins that is a predominant transcription factor known to control the gene expression in mammals and plays a pivotal role in regulating cell signalling in the body under certain physiological and pathological conditions. In cancer cells, such as colon, breast, pancreatic, ovarian, melanoma, and lymphoma, the NF-κB pathway has been reported to be active. In cellular proliferation, promoting angiogenesis, invasion, metastasis of tumour cells and blocking apoptosis, the constitutive activity of NF-κB signalling has been reported. Therefore, immense attention has been given to developing drugs targeting NF-κB signalling pathways to treat many types of tumours. They are a desirable therapeutic target for drugs, and many studies concentrated on recognizing compounds. They may be able to reverse or standstill the growth and spread of tumours that selectively interfere with this pathway. Recently, numerous substances derived from plants have been evaluated as possible inhibitors of the NF-κB pathway. These include various compounds, such as flavonoids, lignans, diterpenes, sesquiterpenes, polyphenols, etc. A study supported by folk medicine demonstrated that plant-derived compounds could suppress NF-κB signalling. Taking this into account, the present review revealed the anticancer potential of naturally occurring compounds which have been verified both by inhibiting the NF-κB signalling and suppressing growth and spread of cancer and highlighting their mechanism of NF-κB inhibition.

Baicalin Promotes CNS Remyelination via PPARγ Signal Pathway

Background and Objectives

Demyelinating diseases in the CNS are characterized by myelin sheath destruction or formation disorder that leads to severe neurologic dysfunction. Remission of such diseases is largely dependent on the differentiation of oligodendrocytes precursor cells (OPCs) into mature myelin-forming OLGs at the demyelinated lesions, which is defined as remyelination. We discover that baicalin (BA), a natural flavonoid, in addition to its well-known antiinflammatory effects, directly stimulates OLG maturation and CNS myelin repair.

Methods

To investigate the function of BA on CNS remyelination, we develop the complementary in vivo and in vitro models, including physiologic neonatal mouse CNS myelinogenesis model, pathologic cuprizone-induced (CPZ-induced) toxic demyelination model, and postnatal OLG maturation assay. Furthermore, molecular docking, pharmacologic regulation, and transgenic heterozygous mice were used to clarify the target and action of the mechanism of BA on myelin repair promotion.

Results

Administration of BA was not only merely effectively enhanced CNS myelinogenesis during postnatal development but also promoted remyelination and reversed the coordination movement disorder in the CPZ-induced toxic demyelination model. Of note, myelin-promoting effects of BA on myelination or regeneration is peroxisome proliferator-activated receptor γ (PPARγ) signaling-dependent.

Discussion

Our work demonstrated that BA promotes myelin production and regeneration by activating the PPARγ signal pathway and also confirmed that BA is an effective natural product for the treatment of demyelinating diseases.

Wogonin inhibits tight junction disruption via suppression of inflammatory response and phosphorylation of AKT/NF-κB and ERK1/2 in rhinovirus-infected human nasal epithelial cells

OBJECTIVE

The maintenance of tight junction integrity contributes significantly to epithelial barrier function. If barrier function is destroyed, cell permeability increases and the movement of pathogens is promoted, further increasing the susceptibility to secondary infection. Here, we examined the protective effects of wogonin on rhinovirus (RV)-induced tight junction disruption. Additionally, we examined the signaling molecules responsible for anti-inflammatory activities in human nasal epithelial (HNE) cells.

METHODS AND RESULTS

Primary HNE cells grown at an air-liquid interface and RPMI 2650 cells were infected apically with RV. Incubation with RV resulted in disruption of tight junction proteins (ZO-1, E-cadherin, claudin-1, and occludin) in the HNE cells. Cell viability of wogonin-treated HNE cells was measured using the MTT assay. Pretreatment with wogonin decreased RV-induced disruption of tight junctions in HNE cells. Furthermore, wogonin significantly decreased RV-induced phosphorylation of Akt/NF-κB and ERK1/2. Additionally, RV-induced generation of reactive oxygen species and RV-induced up-regulation of the production of inflammatory cytokines IL-8 and IL-6 were diminished by wogonin in HNE cells.

CONCLUSION

Wogonin inhibits HRV-induced tight junction disruption via the suppression of inflammatory responses and phosphorylation of Akt/NF-κB and ERK1/2 in HNE cells. These finds will facilitate the development of novel therapeutic strategies.

The effect of a static magnetic field and baicalin or baicalein interactions on amelanotic melanoma cell cultures (C32)

Background

Baicalin and baicalein have antioxidant, anti-inflammatory, hepatoprotective and anti-cancer properties. However, it is not known how a static magnetic field will modify these properties. Therefore, the aim of our study was to evaluate the simultaneous exposure of melanoma cells to flavones and the static magnetic fields that are generated by permanent magnets on the gene expression and the activity of the antioxidant enzymes that are associated with the antioxidant defense system.

Methods and results

Melanoma cells that had been treated with baicalin or baicalein were subjected to a static magnetic fields with a moderate induction. The static magnetic field was emitted by permanent magnets and the cell cultures were carried out in special test chambers. The research included determining the activity of the antioxidant enzymes (superoxide dismutase, glutathione peroxidase and catalase) as well as the gene expression profile. The addition of the flavones to the cell cultures at a concentration of 50 µmol/L resulted increase in the expression of the SOD1, SOD2 and GPX1 genes compared to the nontreated cell cultures. Simultaneous exposure of the melanoma cells to static magnetic field and baicalin or baicalein reduced their mRNA levels compared to the cultures to which only baicalin or baicalein had been added. The change in gene expression was accompanied by changes at the protein level associated with an increase in the activity of antioxidant enzymes.

Conclusion

We showed that baicalin or baicalein have anticancer properties by disturbing the redox homeostasis in melanoma cells and also increases the antioxidant system gene expression. There was also an antagonistic interaction between the studied flavones and the static magnetic field, which cause a decrease in the anticancer effects of baicalin or baicalein.

Polyphenols from traditional Chinese medicine and Mediterranean diet are effective against Aβ toxicity in vitro and in vivo in Caenorhabditis elegans

The potential of naturally occurring polyphenols as nutraceuticals to prevent and/or treat Alzheimer's disease is studied. Five structurally related flavones and four tyrosols were tested in vitro in human amyloid-β peptide aggregation assays. The most promising compounds were two flavones, scutellarein and baicalein, and two tyrosols hydroxytyrosol and hydroxytyrosol acetate. These compounds caused a dose-dependent reduction of Aβ-peptide aggregation up to 90% for the flavones and 100% for the tyrosols, at concentrations of 83.3 μM and 33.3 mM, respectively. The IC₅₀ value obtained for scutellarein was 22.5 μM, and was slightly higher for baicalein, 25.9 μM, while for hydroxytyrosol and hydroxytyrosol acetate they were 0.57 mM and 0.62 mM. Given these results, the compounds were selected to conduct in vivo assays with the Caenorhabditis elegans animal model of Alzheimer's disease. The amyloid anti-aggregation ability of these polyphenols was demonstrated in in vivo aggregation assays in which 1 mM hydroxytyrosol reduced the amyloid plaques in the mutant strain CL2331 by 43%. The neuroprotective effect was evaluated in chemotaxis experiments carried out with transgenic strain CL2355 that expresses the human amyloid-β peptide in the neurons. The chemotaxis index was improved by 240% when the neuron-impaired animals were treated with 1 mM hydroxytyrosol. The results indicate that the four molecules would be viable candidates to develop nutraceuticals that interfere in amyloid-β peptide aggregation and, consequently, prevent and/or treat Alzheimer's disease.

Folic Acid Decorated Zeolitic Imidazolate Framework (ZIF-8) Loaded with Baicalin as a Nano-Drug Delivery System for Breast Cancer Therapy

Background

Baicalin (BAN) has attracted widespread attention due to its low-toxicity and efficient antitumor activity, but its poor water solubility and low bioavailability severely limit its clinical application. Development of a targeted drug delivery system is a good strategy to improve the antitumor activity of baicalin.

Methods

We prepared a BAN nano-drug delivery system PEG-FA@ZIF-8@BAN with a zeolite imidazole framework-8 (ZIF-8) as a carrier, which can achieve the response of folate receptor (FR). We characterized this system in terms of morphology, particle size, zeta-potential, infrared (IR), ultraviolet (UV), x-ray diffraction (XRD), and Brunel-Emmett-Teller (BET), and examined the in vitro cytotoxicity and cellular uptake properties of PEG-FA@ZIF-8@BAN using MCF-7 cells. Lastly, we established a 4T1 tumor-bearing mouse model and evaluated its in vivo anti-mammary cancer activity.

Results

The PEG-FA@ZIF-8@BAN nano-delivery system had good dispersion with a BAN loading efficiency of 41.45 ± 1.43%, hydrated particle size of 176 ± 8.1 nm, Zeta-potential of −23.83 ± 1.1 mV, and slow and massive drug release in an acidic environment (pH 5.0), whereas release was 11.03% in a neutral environment (pH 7.4). In vitro studies showed that PEG-FA@ZIF-8@BAN could significantly enhance the killing effect of BAN on MCF-7 cells, and the folic acid-mediated targeting could lead to better uptake of nanoparticles by tumor cells and thus better killing of cancer cells. In vivo studies also showed that PEG-FA@ZIF-8@BAN significantly increased the inhibition of the proliferation of solid breast cancer tumors (p < 0.01 or p < 0.001).

Conclusion

The PEG-FA@ZIF-8@BAN nano-drug delivery system significantly enhanced the anti-breast cancer effect of baicalin both in vivo and in vitro, providing a more promising drug delivery system for the clinical applications and tumor management.

Baicalin-loaded folic acid-modified albumin nanoparticles (FA-BSANPs/BA) induce autophagy in MCF-7 cells via ROS-mediated p38 MAPK and Akt/mTOR pathway

Background

Breast cancer is the most frequently occurring cancer among women. Baicalin has been shown to inhibit breast cancer proliferation, but poor aqueous solubility and unknown mechanism of action limit its application. This study aimed to investigate the antiproliferative effects of baicalin-loaded folic acid-modified albumin nanoparticles (FA-BSANPs/BA) in breast cancer MCF-7 cells and its relationship with autophagy and ROS-mediated p38 MAPK and Akt/mTOR signaling pathways. Cell viability was detected by MTT assay. Flow cytometry and fluorescence microscopy were used to detect cell cycle, apoptosis and autophagy. Western blot was used to detect protein expression.

Results

Compared with the control and free baicalin groups, FA-BSANPs/BA inhibited viability of MCF-7 cells and increased cells in S phase, apoptotic bodies, pro-apoptotic proteins, autophagy markers and autophagosomes. These effects could be reversed when combined with the autophagy inhibitor 3-methyladenine. FA-BSANPs/BA increased the levels of phosphorylated p38 MAPK, inhibited the levels of phosphorylated Akt and mTOR, and increased the level of ROS in MCF-7 cells. The effects of FA-BSANPs/BA could be reversed or enhanced using inhibitors of Akt, mTOR, p38 MAPK and ROS scavengers.

Conclusions

Encapsulation in folate albumin nanoparticles improved the antiproliferative activity of baicalin. FA-BSANPs/BA induced autophagy and apoptosis via ROS-mediated p38 MAPK and Akt/mTOR signaling pathways in human breast cancer cells.

Challenges in Medicinal and Aromatic Plants DNA Barcoding-Lessons from the Lamiaceae

The potential value of DNA barcoding for the identification of medicinal plants and authentication of traded plant materials has been widely recognized; however, a number of challenges remain before DNA methods are fully accepted as an essential quality control method by industry and regulatory authorities. The successes and limitations of conventional DNA barcoding are considered in relation to important members of the Lamiaceae. The mint family (Lamiaceae) contains over one thousand species recorded as having a medicinal use, with many more exploited in food and cosmetics for their aromatic properties. The family is characterized by a diversity of secondary products, most notably the essential oils (EOs) produced in external glandular structures on the aerial parts of the plant that typify well-known plants of the basil (Ocimum), lavender (Lavandula), mint (Mentha), thyme (Thymus), sage (Salvia) and related genera. This complex, species-rich family includes widely cultivated commercial hybrids and endangered wild-harvested traditional medicines, and examples of potential toxic adulterants within the family are explored in detail. The opportunities provided by next generation sequencing technologies to whole plastome barcoding and nuclear genome sequencing are also discussed with relevant examples.

Borcalein: a Carborane-Based Analogue of Baicalein with 12-Lipoxygenase-Independent Toxicity

12-Lipoxygenase is crucial for tumour angiogenesis. 5,6,7-Trihydroxy-2-phenyl-4H-1-benzopyran-4-one (baicalein) is a suitable inhibitor for this enzyme but is rapidly metabolised in vivo. Thus, an improvement of the metabolic stability is necessary to enhance the therapeutic efficiency. An emerging approach to enhance metabolic stability of carbon-based pharmaceuticals is the use of metabolically stable, non-toxic boron clusters, such as dicarba-closo-dodecaborane(12)s (carboranes) as phenyl mimetics. Therefore, the unsubstituted phenyl ring of baicalein was replaced by meta-carborane, resulting in borcalein, the carborane analogue of baicalein. This substitution resulted in a decreased inhibitory activity toward 12-lipoxygenase, but led to increased toxicity in melanoma (A375, B16, B16F10) and colon cancer cell lines (SW480, HCT116, CT26CL25) with decreased tumour selectivity in comparison to baicalein. Surprisingly, borcalein displays a different mechanism of cytotoxicity with increased intracellular production of reactive oxygen species (ROS), reactive nitrogen species (RNS) and nitric oxide (NO).

Two types of O-methyltransferase are involved in biosynthesis of anticancer methoxylated 4'-deoxyflavones in Scutellaria baicalensis Georgi

The medicinal plant Scutellaria baicalensis Georgi is rich in specialized 4'-deoxyflavones, which are reported to have many health-promoting properties. We assayed Scutellaria flavones with different methoxyl groups on human cancer cell lines and found that polymethoxylated 4'-deoxyflavones, like skullcapflavone I and tenaxin I have stronger ability to induce apoptosis compared to unmethylated baicalein, showing that methoxylation enhances bioactivity as well as the physical properties of specialized flavones, while having no side-effects on healthy cells. We investigated the formation of methoxylated flavones and found that two O-methyltransferase (OMT) families are active in the roots of S. baicalensis. The Type II OMTs, SbPFOMT2 and SbPFOMT5, decorate one of two adjacent hydroxyl groups on flavones and are responsible for methylation on the C6, 8 and 3'-hydroxyl positions, to form oroxylin A, tenaxin II and chrysoeriol respectively. The Type I OMTs, SbFOMT3, SbFOMT5 and SbFOMT6 account mainly for C7-methoxylation of flavones, but SbFOMT5 can also methylate baicalein on its C5 and C6-hydroxyl positions. The dimethoxylated flavone, skullcapflavone I (found naturally in roots of S. baicalensis) can be produced in yeast by co-expressing SbPFOMT5 plus SbFOMT6 when the appropriately hydroxylated 4'-deoxyflavone substrates are supplied in the medium. Co-expression of SbPFOMT5 plus SbFOMT5 in yeast produced tenaxin I, also found in Scutellaria roots. This work showed that both type I and type II OMT enzymes are involved in biosynthesis of methoxylated flavones in S. baicalensis.

Ursolic Acid Decreases the Proliferation of MCF-7 Cell-Derived Breast Cancer Stem-Like Cells by Modulating the ERK and PI3K/AKT Signaling Pathways

Cancer stem cells are strong drivers of metastasis and cancer relapse, which makes them important therapeutic targets. Ursolic acid (UA), a pentacyclic triterpenoid, has anticancer effects in various types of cancer; however, little is known about its effect on the growth of MCF-7 cell-derived breast cancer stem (BCS)-like cells in estrogen receptor positive breast cancer. In this study, the anticancer activity of UA in MCF-7 cell-derived BCS-like cells and its mechanism of action were evaluated. Furthermore, its inhibitory effects on the proliferation of MCF-7 cell-derived BCS-like cells were compared with that on MCF-7 cells. In MCF-7 cells, UA increased p53 and p21 expression but decreased cyclin D, cyclin E, CDK4, and CDK2 expression to induce cell cycle arrest in the G0/G1 phase. Moreover, UA significantly suppressed migration, invasion, and colony formation in MCF-7 cells, and suppressed mammosphere formation in a concentration- dependent manner. In MCF-7 cell-derived BCS-like cells, UA significantly decreased migration, suppressed p-PI3K, p-AKT, and p-ERK expression, and enhanced p-FoxO1/FoxO3a expression. Accordingly, in MCF-7 cell-derived BCS-like cells, UA suppressed proliferation in part by downregulating ERK and PI3K/AKT signaling pathways. These findings provide the first evidence for the selective effects of UA in BCSs.

Formulation and performance evaluation of polymeric mixed micelles encapsulated with baicalein for breast cancer treatment

The present study is aimed to formulate baicalein-loaded mixed micelles to enhance the solubility and oral bioavailability. Baicalein encapsulated D-α-tocopherol polyethylene glycol 1000 succinate (TPGS) and pluronic F127 (F127) combined micelles were prepared and investigated for anticancer effect. The optimized formulation contains 25.04 ± 0.24 nm mean particle size of micelles with a zeta potential value of -4.01 ± 0.5 mV. The calculated entrapment efficiency percentage of baicalein within the micellar structure was 83.43 ± 0.13% and the in vitro release of baicalein from micelles displayed a sustained release profile at pH 7.4. The incorporation of baicalein within micelles core was also confirmed by FTIR analysis of formulation, which hardly represents the characteristic peak of baicalein, indicating successful entrapment of the drug. In vitro cell culture experiments revealed baicalein-loaded micelles significantly enhanced cellular uptake and cytotoxicity against MDAMB-231 cell lines in comparison to free baicalein. Additionally, as compared to free baicalein, baicalein micelles demonstrated greater apoptosis-inducing potential while the results of the cell cycle study exhibited arrest of cells at the G0/G1 phase of the cell cycle. Results of ROS (reactive oxygen species) and MMP (mitochondrial membrane potential) assay revealed the ROS-dependent mitochondrial-mediated apoptosis pathway utilized by developed formulation to inhibit cell proliferation. Thus, the developed nano micelles can serve as a potent carrier system for baicalein against breast cancer.