Research Progress of Quercetin Delivery Systems

Enhanced efficacy of quercetin and taxifolin encapsulated with pH-responsive injectable BSA hydrogel for targeting triple-negative breast cancer cells

Quercetin (QUE) and Taxifolin (TAX) are natural flavonoids with diverse biological activities, holding promise for cancer treatment. However, their clinical application is limited by their poor solubility and bioavailability. Self-assembled bovine serum albumin (BSA) hydrogels have demonstrated biocompatibility and proteolytic stability, making them suitable platforms for drug delivery. The present study validated the anticancer efficacy of QUE, TAX, and DOX encapsulated in BSA hydrogel (QUE@ BSA hydrogel, TAX@ BSA hydrogel, and DOX@ BSA hydrogel), which exhibited 93.5, 90 and 91.2 %% entrapment efficiency, respectively, and controlled release profiles with 90.8,95.8 and 90.8 % drug release, respectively, at lower pH using MDA-MB 231 and MDA-MB 468 TNBC cell lines. Characterization by SEM, XRD, FT-IR and DLS revealed distinctive features of QUE@ BSA hydrogel, TAX@ BSA hydrogel, and DOX@BSA hydrogels, suggesting potential for targeted drug delivery. Further, investigations showed that separate treatment with QUE@BSA hydrogel, TAX@BSA hydrogel, and DOX@BSA hydrogel disrupted cell membrane integrity, akin to inducing cytotoxicity with IC50 of 12.90, 15.52 and 6.9 μM, respectively, in MDA-MB 231 cells and 16.67, 19.16 and 5.2 μM, respectively, in MDA-MB 468 cells. Moreover, they reduced mammosphere formation and cell migration. Additionally, they induced cell cycle arrest, reduced cell proliferation, and induced apoptosis in TNBC cells. They also induced ROS generation and ER stress, highlighting their potential to suppress TNBC progression. Overall, this study underscores the promise of QUE@ BSA hydrogel and TAX@BSA hydrogel as effective anticancer agents against TNBC cell lines in line with DOX@BSA hydrogel, offering controlled drug release and enhanced therapeutic outcomes.

Natural polyphenols: A protective approach to reduce colorectal cancer

Background

A form of cancer that affects the rectum or colon (large intestine) is called colorectal cancer (CRC). The main risk factors for CRC include dietary, lifestyle, and environmental variables. Currently natural polyphenols have demonstrated impressive anticarcinogenic capabilities.

Objective

The main objective was to provide an updated, thorough assessment of the defensive mechanism of natural polyphenols for the global suppression of colorectal cancer. More precisely, this study aimed to analyze a set of chosen polyphenols with demonstrated safety, effectiveness, and biochemical defense mechanism on colon cancer models in order to facilitate future research.

Methods

This review was carried out with purposefully attentive and often updated scientific databases, including PubMed, Scopus, Science Direct, and Web of Science. After selecting approximately 178 potentially relevant papers based just on abstracts, 145 studies were meticulously reviewed and discussed.

Results

The outcomes disclosed that anti-CRC mechanisms of natural polyphenols involved the control of several molecular and signaling pathways. Natural polyphenols have also been shown to have the ability to limit the growth and genesis of tumors via altering the gut microbiota and cancer stem cells. However, the biochemical uses of many natural polyphenols have remained restricted because of their truncated water solubility and low bioavailability. In order to attain synergistic properties it is recommended to combine the use of different natural polyphenols because of their low bioavailability and volatility. However, the use of lipid-based nano- and micro-carriers also may be helpful to solve these problems with efficient distribution system to target sites.

Conclusion

In conclusion, the use of polyphenols for CRC treatment appears promising. To ascertain their efficacy, more clinical research is anticipated.

Carbonization of quercetin into nanogels: a leap in anticoagulant development

Quercetin, a flavonoid abundantly found in onions, fruits, and vegetables, is recognized for its pharmacological potential, especially for its anticoagulant properties that work by inhibiting thrombin and coagulation factor Xa. However, its clinical application is limited due to poor water solubility and bioavailability. To address these limitations, we engineered carbonized nanogels derived from quercetin (CNGsQur) using controlled pyrolysis and polymerization techniques. This led to substantial improvements in its anticoagulation efficacy, water solubility, and biocompatibility. We generated a range of CNGsQur by subjecting quercetin to varying pyrolytic temperatures and then assessed their anticoagulation capacities both in vitro and in vivo. Coagulation metrics, including thrombin clotting time (TCT), activated partial thromboplastin time (aPTT), and prothrombin time (PT), along with a rat tail bleeding assay, were utilized to gauge the efficacy. CNGsQur showed a pronounced extension of coagulation time compared to uncarbonized quercetin. Specifically, CNGsQur synthesized at 270 °C (CNGsQur270) exhibited the most significant enhancement in TCT, with a binding affinity to thrombin exceeding 400 times that of quercetin. Moreover, variants synthesized at 310 °C (CNGsQur310) and 290 °C (CNGsQur290) showed the most substantial delays in PT and aPTT, respectively. Our findings indicate that the degree of carbonization significantly influences the transformation of quercetin into various CNGsQur forms, each affecting distinct coagulation pathways. Additionally, both intravenous and oral administrations of CNGsQur were found to extend rat tail bleeding times by up to fivefold. Our studies also demonstrate that CNGsQur270 effectively delays and even prevents FeCl3-induced vascular occlusion in a dose-dependent manner in mice. Thus, controlled pyrolysis offers an innovative approach for generating quercetin-derived CNGs with enhanced anticoagulation properties and water solubility, revealing the potential for synthesizing self-functional carbonized nanomaterials from other flavonoids for diverse biomedical applications.

Can Compounds of Natural Origin Be Important in Chemoprevention? Anticancer Properties of Quercetin, Resveratrol, and Curcumin-A Comprehensive Review

Malignant tumors are the second most common cause of death worldwide. More attention is being paid to the link between the body's impaired oxidoreductive balance and cancer incidence. Much attention is being paid to polyphenols derived from plants, as one of their properties is an antioxidant character: the ability to eliminate reactive oxygen and nitrogen species, chelate specific metal ions, modulate signaling pathways affecting inflammation, and raise the level and activity of antioxidant enzymes while lowering those with oxidative effects. The following three compounds, resveratrol, quercetin, and curcumin, are polyphenols modulating multiple molecular targets, or increasing pro-apoptotic protein expression levels and decreasing anti-apoptotic protein expression levels. Experiments conducted in vitro and in vivo on animals and humans suggest using them as chemopreventive agents based on antioxidant properties. The advantage of these natural polyphenols is low toxicity and weak adverse effects at higher doses. However, the compounds discussed are characterized by low bioavailability and solubility, which may make achieving the blood concentrations needed for the desired effect challenging. The solution may lie in derivatives of naturally occurring polyphenols subjected to structural modifications that enhance their beneficial effects or work on implementing new ways of delivering antioxidants that improve their solubility and bioavailability.

Pharmacological and mechanistic aspects of quercetin in osteoporosis

Osteoporosis (OP) is a bone disease associated with increasing age. Currently, the most common medications used to treat OP are anabolic agents, anti-resorptive agents, and medications with other mechanisms of action. However, many of these medications have unfavorable adverse effects or are not intended for long-term use, potentially exerting a severe negative impact on a patient's life and career and placing a heavy burden on families and society. There is an urgent need to find new drugs that can replace these and have fewer adverse effects. Quercetin (Que) is a common flavonol in nature. Numerous studies have examined the therapeutic applications of Que. However, a comprehensive review of the anti-osteoporotic effects of Que has not yet been conducted. This review aimed to describe the recent studies on the anti-osteoporotic effects of Que, including its biological, pharmacological, pharmacokinetic, and toxicological properties. The outcomes demonstrated that Que could enhance OP by increasing osteoblast differentiation and activity and reducing osteoclast differentiation and activity via the pathways of Wnt/β-catenin, BMP/SMAD/RUNX2, OPG/RANKL/RANK, ERK/JNK, oxidative stress, apoptosis, and transcription factors. Thus, Que is a promising novel drug for the treatment of OP.

Validation of an HPLC-DAD Method for Quercetin Quantification in Nanoparticles

The evaluation of the efficacy of incorporation of quercetin in nanoparticles is crucial, both for the development and quality control of pharmaceutical formulations. The validation of analytical methods for the precise quantification of quercetin is useful for the evaluation of various potential quercetin delivery systems and quercetin pharmacokinetics. This work aimed to validate a high-performance liquid chromatography with diode array detection (HPLC-DAD) method for quercetin detection and quantification in nanoparticles. Different mobile phase conditions and detection wavelengths (254 and 368 nm) were tested, and the major validation parameters were assessed (precision, accuracy, linearity, sensitivity, stability, and selectivity). The best peak resolution was obtained when quercetin was analyzed at 368 nm with a mobile phase of 1.5% acetic acid and a water/acetonitrile/methanol ratio of 55:40:5. Under these conditions, quercetin also eluted rapidly (retention time of 3.6 min). The method proved to be linear (R2 > 0.995), specific, and repeatable (variation coefficient between 2.4% and 6.7%) and presented intermediate precision (variation coefficient between 7.2% and 9.4%). The accuracy of the analysis ranged between 88.6% and 110.7%, and detection and quantification limits were 0.046 and 0.14 µg/mL, respectively. Quercetin solutions were more stable when stored at 4 °C than at room temperature or -20 °C. This validated method satisfied more parameters of bias assessment than most recent methods for quercetin determination and presented itself as more sensitive and efficient than general spectrophotometric methods. The method was successfully used for the analysis of quercetin incorporation in nanoparticles and will be evaluated in the future for its adequacy for the determination of quercetin in more complex matrices.

Targeting beta-catenin signaling for prevention of colorectal cancer - Nutraceutical, drug, and dietary options

Progressive up-regulation of β-catenin signaling is very common in the transformation of colorectal epithelium to colorectal cancer (CRC). Practical measures for opposing such signaling hence have potential for preventing or slowing such transformation. cAMP/PKA activity in colon epithelium, as stimulated by COX-2-generated prostaglandins and β2-adrenergic signaling, boosts β-catenin activity, whereas cGMP/PKG signaling has the opposite effect. Bacterial generation of short-chain fatty acids (as supported by unrefined high-carbohydrate diets, berberine, and probiotics), dietary calcium, daily aspirin, antioxidants opposing cox-2 induction, and nicotine avoidance, can suppress cAMP production in colonic epithelium, whereas cGMP can be boosted via linaclotides, PDE5 inhibitors such as sildenafil or icariin, and likely high-dose biotin. Selective activation of estrogen receptor-β by soy isoflavones, support of adequate vitamin D receptor activity with UV exposure or supplemental vitamin D, and inhibition of CK2 activity with flavanols such as quercetin, can also oppose β-catenin signaling in colorectal epithelium. Secondary bile acids, the colonic production of which can be diminished by low-fat diets and berberine, can up-regulate β-catenin activity by down-regulating farnesoid X receptor expression. Stimulation of PI3K/Akt via insulin, IGF-I, TLR4, and EGFR receptors boosts β-catenin levels via inhibition of glycogen synthase-3β; plant-based diets can down-regulate insulin and IGF-I levels, exercise training and leanness can keep insulin low, anthocyanins and their key metabolite ferulic acid have potential for opposing TLR4 signaling, and silibinin is a direct antagonist for EGFR. Partially hydrolyzed phytate can oppose growth factor-mediated down-regulation of β-catenin by inhibiting Akt activation. Multifactorial strategies for safely opposing β-catenin signaling can be complemented with measures that diminish colonic mutagenesis and DNA hypomethylation - such as avoidance of heme-rich meat and charred or processed meats, consumption of phase II-inductive foods and nutraceuticals (e.g., Crucifera), and assurance of adequate folate status.