Low dose of quercetin-loaded pectin/casein microparticles reduces the oxidative stress in arthritic rats

Amplifying therapeutic potential through optimization of bioavailability of poorly soluble flavonols via albumin-based nanoparticles

OBJECTIVE

Flavonols have different pharmacological actions that render them highly promising therapeutic targets. However, their water solubility and bioavailability are low, which restricts their therapeutic potential. ABNPs, albumin-based nanoparticles, are potential nanocarriers that enhance flavonol solubility, stability, and targeted delivery. By utilizing ABNPs, in this work we provide a detailed overview of strategies employed to attain maximum bioavailability of poorly water-soluble flavonols. The review critically evaluates ABNP-mediated delivery's pharmacokinetic advantage, physicochemical properties, and formulation principles. We also highlight existing gaps in research, such as the need for stringent in vivo validity tests, standardized formulation procedures, and in-depth mechanistic understanding of flavonol-albumin interactions.

SIGNIFICANCE

Despite having potential therapeutic activities, the utilization of flavonoids in the form of medication is limited. Some recent studies have shown that flavonoids exhibit low solubility, low permeability and chemical instability, thereby limiting their bioavailability and therapeutic responses.

METHODS

To overcome these drawbacks, multiple novel drug delivery approaches have emerged in the pharmaceutical research.

RESULTS

These novel approaches seem to offer a viable foundation for improving the bioavailability of the flavonoids and positioning them as viable therapeutic options. Out of all the polymers implemented in enhancing the solubility and bioavailability of the flavonoids, albumin-based nanomaterials have been the most efficacious one.

CONCLUSION

Compared to all other polymeric nano-carriers, albumin nano-carriers offer a greater scale of drug entrapment and drug loading because of their capacity for surface modification, crosslinking, conjugation, coupling, and characteristics including biodegradability and biocompatibility.

Patches containing quercetin microcapsules to ameliorate dermal herpes simplex virus injuries in mice

This study aimed to develop patches containing quercetin-loaded microcapsules and to evaluate their in vitro and in vivo safety and efficacy in preclinical surveys. A set of in vitro experiments evidenced the virucidal activity of quercetin against the HSV-1-KOS (sensitive to acyclovir) and HSV-1-AR (resistant to acyclovir) strains, with improved outcomes upon the first. The patches presented a homogeneous aspect, were easily handled, had a suitable bioadhesion, and possessed mechanical properties of soft and weak material, besides a pH compatible with human skin. The in vitro release profile of quercetin showed an initial burst release, followed by a controlled release rate, which was best described by Gompertz kinetics (R2 of 0.93). Using quercetin-loaded patches for treating HSV-1-KOS-induced injuries was feasible since they were well tolerated in the in vivo skin irritation test and significantly decreased the injury scores until the fourth out of eight days of treatment in mice compared to acyclovir cream (50 mg/g). Altogether, the in vitro and in vivo antiviral assays indicate that this flavonol acts in the earlier stage of the infection, likely impairing the HSV-1 adsorption to the cell. The anti-inflammatory capacity of the quercetin-loaded patches was noteworthy as evidenced by histological analysis. These findings bring prospects for safer and more effective management of mucocutaneous HSV-1 injuries.

Effects of resveratrol on rheumatic symptoms and hepatic metabolism of arthritic rats

OBJECTIVES

Resveratrol has been studied as a potential agent for treating rheumatic conditions; however, this compound suppresses glucose synthesis and glycogen catabolism when infused in perfused livers of both arthritic and healthy rats. This study investigated the effects of oral administration of resveratrol on inflammation and liver metabolism in rats with arthritis induced by Freund's adjuvant, which serves as rheumatoid arthritis model.

METHODS

Holtzman rats, both healthy and exhibiting arthritic symptoms, were orally treated with resveratrol at doses varying from 25 to 500 mg/kg for a 5-day period preceding arthritis induction, followed by an additional 20-day period thereafter. Paw edema, arthritic score and hepatic myeloperoxidase activity were assessed to evaluate inflammation. Glycogen catabolism and gluconeogenesis from lactate were respectively evaluated in perfused livers from fed and fasted rats.

RESULTS

Resveratrol decreased the liver myeloperoxidase activity at doses above 100 mg/kg, and decreased the paw edema and delayed the arthritic score at doses above 250 mg/kg. The hepatic gluconeogenesis was decreased in arthritic rats and resveratrol did not improve it. However, resveratrol did not negatively modify the gluconeogenesis in livers of healthy and arthritic rats. Glycogen catabolism was in part and slightly modified by resveratrol in the liver of arthritic and healthy rats.

CONCLUSIONS

It is improbable that resveratrol negatively affects the liver metabolism, especially considering that gluconeogenesis is highly fragile to changes in cellular architecture. The findings suggest that resveratrol could serve as alternative for treating rheumatoid arthritis. Nevertheless, prudence is advised regarding its transient effects on liver metabolism.

Metabolic effects of quercetin on inflammatory and autoimmune responses in rheumatoid arthritis are mediated through the inhibition of JAK1/STAT3/HIF-1α signaling

BACKGROUND

Rheumatoid arthritis, a chronic autoimmune disease, is characterized by synovial hyperplasia and cartilage erosion. Here, we investigated the potential mechanism of action of quercetin, the main component of flavonoids, in treating rheumatoid arthritis.

OBJECT

To examine the anti-arthritic effects of quercetin and elucidate the specific mechanisms that differentiate its metabolic effects on autoimmune and inflammatory responses at the synovial cell level.

METHODS

We created a collagen-induced arthritis (CIA) model in Wistar rats, which were administered quercetin (50 or 100 mg/kg) continuously for four weeks via stomach perfusion. The arthritis score, histopathological staining, radiological assessment, and serum biochemical parameters were used to study the impact of quercetin on disease improvement. Additionally, immunofluorescence was employed to detect JAK1/STAT3/HIF-1α expression in rat joints. Moreover, the effects of quercetin (20, 40, and 80 µmol/L) on the properties and behavior of synovial fibroblasts were evaluated in an in vitro MH7A cell model using flow cytometry, CCK8, and transwell assays. Further, the mRNA expression levels of inflammatory cytokines IL1β, IL6, IL17, and TNFα were assessed by quantitative real-time PCR. Glucose, lactate, lactate dehydrogenase, pyruvate, pyruvate dehydrogenase, and adenosine triphosphate assay kits were employed to measure the metabolic effects of quercetin on synovial fibroblasts. Finally, immunoblotting was used to examine the impact of quercetin on the JAK1/STAT3/HIF-1α signaling pathway in synovial fibroblasts.

RESULTS

In vivo experiments confirmed the favorable effects of quercetin in CIA rats, including an improved arthritis score and reduced ankle bone destruction, in addition to a decrease in the pro-inflammatory cytokines IL-1β, IL-6, IL-17, and TNF-α in serum. Immunofluorescence verified that quercetin may ameliorate joint injury in rats with CIA by inhibiting JAK1/STAT3/HIF-1α signaling. Various in vitro experiments demonstrated that quercetin effectively inhibits IL-6-induced proliferation of MH7A cells and reduces their migratory and invasive behavior, while inducing apoptosis and reducing the expression of the pro-inflammatory cytokines IL1β, IL6, IL17, and TNFα at the mRNA level. Quercetin caused inhibition of glucose, lactate, lactate dehydrogenase, pyruvate, and adenosine triphosphate and increased pyruvate dehydrogenase expression in MH7A cells. It was further confirmed that quercetin may inhibit energy metabolism and inflammatory factor secretion in MH7A cells through JAK1/STAT3/HIF-1α signaling.

CONCLUSIONS

Quercetin's action on multiple target molecules and pathways makes it a promising treatment for cartilage injury in rheumatoid arthritis. By reducing joint inflammation, improving joint metabolic homeostasis, and decreasing immune system activation energy, quercetin inhibits the JAK1/STAT3/HIF-1α signaling pathway to improve disease status.

Quercetin improves the protection of hydroxysafflor yellow a against cerebral ischemic injury by modulating of blood-brain barrier and src-p-gp-mmp-9 signalling

Protection of the structural and functional integrity of the blood-brain barrier (BBB) is crucial for treating ischemic stroke (IS). Hydroxysafflor yellow A (HSYA) and quercetin (Quer), two main active components in the edible and medicinal plant Carthamus tinctorius L., have been reported to exhibit neuroprotective effects. We investigated the anti-IS and BBB-protective properties of HSYA and Quer and the underlying mechanisms. They decreased neurological deficits in middle cerebral artery occlusion (MCAO) mice, while their combination showed better effects. Importantly, HSYA and Quer ameliorated BBB permeability. Their effects on reduction of both EB leakage and infarct volume were similar, which may contribute to improved locomotor activities. Moreover, HSYA and Quer showed protective effects for hCMEC/D3 monolayer against oxygen-glucose deprivation. Src, p-Src, MMP-9, and P-gp were associated with ingredients treatments. Furthermore, molecular docking and molecular dynamics simulations revealed stable and tight binding modes of ingredients with Src and P-gp. The current study supports the potential role of HSYA, Quer, and their combination in the treatment of IS by regulating BBB integrity.

Enhancing basil essential oil microencapsulation using pectin/casein biopolymers: Optimization through D-optimal design, controlled release modeling, and characterization

A D-optimal design was employed to optimize the microencapsulation (MEC) of basil essential oil (BEO) within a biopolymer matrix using the complex coacervation technique. BEO microcapsules (BEO-MCs) obtained under the optimal conditions exhibited high yield and efficiency with 80.45 ± 0.01 % and 93.10 ± 0.18 %, respectively. The successful MEC of BEO with an average particle size of 4.81 ± 2.86 μm was confirmed by ATR-FTIR, X-RD, and SEM analyses. Furthermore, the thermal stability of BEO-MCs was assessed using TGA-DSC analysis, which provided valuable insights into the MC's thermal stability. Furthermore, the proposed model, with a high R2 value (0.99) and low RMSE (1.56 %), was the most suitable one among the tested models for the controlled release kinetics of the optimal BEO-MCs under simulated gastrointestinal conditions. The successful optimization of BEO MEC using biopolymers through the D-optimal design could be a promising avenue for food and pharmaceutical industries, providing new strategies for the development of effective products.

Characterization and bioactivities of coffee husks extract encapsulated with polyvinylpyrrolidone

Coffee processing generates large amounts of residues of which a portion still has bioactive properties due to their richness in phenolic compounds. This study aimed to obtain a coffee husks extract (CHE) and to encapsulate it (ECHE) with polyvinylpyrrolidone using a one-step procedure of solid dispersion. The extraction and encapsulation yields were 9.1% and 92%, respectively. Thermal analyses revealed that the encapsulation increased the thermal stability of CHE and dynamic light scattering analyses showed a bimodal distribution of size with 81% of the ECHE particles measuring approximately 711 nm. Trigonelline and caffeine were the main alkaloids and quercetin the main phenolic compound in CHE, and the encapsulation tripled quercetin extraction. The total phenolics content and the antioxidant activity of ECHE, assayed with three different procedures, were higher than those of CHE. The antioxidant activity and the bioaccessibility of the phenolic compounds of ECHE were also higher than those of CHE following simulated gastrointestinal digestion (SGID). Both CHE and ECHE were not toxic against Alliumcepa cells and showed similar capacities for inhibiting the pancreatic α-amylase in vitro. After SGID, however, ECHE became a 1.9-times stronger inhibitor of the α-amylase activity in vitro (IC50 = 8.5 mg/mL) when compared to CHE. Kinetic analysis revealed a non-competitive mechanism of inhibition and in silico docking simulation suggests that quercetin could be contributing significantly to the inhibitory action of both ECHE and CHE. In addition, ECHE (400 mg/kg) was able to delay by 50% the increases of blood glucose in vivo after oral administration of starch to rats. This finding shows that ECHE may be a candidate ingredient in dietary supplements used as an adjuvant for the treatment of diabetes.

Mechanism of action of quercetin in rheumatoid arthritis models: meta-analysis and systematic review of animal studies

Quercetin, a typical flavonoid derived from a common natural plant, has multiple biological activities. Previous research in animal models has demonstrated the effectiveness of quercetin in treating rheumatoid arthritis (RA). The pharmacological effects and probable mechanisms of quercetin were evaluated in this study. Three databases, PubMed, Web of Science, and Embase, were searched for relevant studies from the creation of the databases to November 2022. Methodological quality was assessed using the SYRCLE risk of bias tool. STATA 15.1 was used to perform the statistical analysis. This research included 17 studies involving 251 animals. The results indicated that quercetin was able to reduce arthritis scores, paw swelling, histopathological scores, interleukin-1β (IL-1β), interleukin-6 (IL-6), interleukin-17 (IL-17), tumor necrosis factor-α (TNF-α), monocyte chemotactic protein-1 (MCP-1), C-reactive protein (CRP), malondialdehyde (MDA), reactive oxygen species (ROS), thiobarbituric acid reactive substances (TBARS), nuclear factor kappa B (NF-kB) and increase interleukin-10 (IL-10), catalase (CAT), glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), glutathione (GSH), and heme oxygenase-1 (HO-1). These may be related to quercetin's potential anti-inflammatory, anti-oxidative stress, and osteoprotective properties. However, more high-quality animal studies are needed to assess the effect of quercetin on RA. Additionally, the safety of quercetin requires further confirmation. Given the importance of the active ingredient, dose selection and the improvement of quercetin's bioavailability remain to be explored.

Exploiting Polyphenol-Mediated Redox Reorientation in Cancer Therapy

Polyphenol, one of the major components that exert the therapeutic effect of Chinese herbal medicine (CHM), comprises several categories, including flavonoids, phenolic acids, lignans and stilbenes, and has long been studied in oncology due to its significant efficacy against cancers in vitro and in vivo. Recent evidence has linked this antitumor activity to the role of polyphenols in the modulation of redox homeostasis (e.g., pro/antioxidative effect) in cancer cells. Dysregulation of redox homeostasis could lead to the overproduction of reactive oxygen species (ROS), resulting in oxidative stress, which is essential for many aspects of tumors, such as tumorigenesis, progression, and drug resistance. Thus, investigating the ROS-mediated anticancer properties of polyphenols is beneficial for the discovery and development of novel pharmacologic agents. In this review, we summarized these extensively studied polyphenols and discussed the regulatory mechanisms related to the modulation of redox homeostasis that are involved in their antitumor property. In addition, we discussed novel technologies and strategies that could promote the development of CHM-derived polyphenols to improve their versatile anticancer properties, including the development of novel delivery systems, chemical modification, and combination with other agents.

Epimedii Herba: An ancient Chinese herbal medicine in the prevention and treatment of rheumatoid arthritis

Rheumatoid arthritis (RA) is a chronic, progressive inflammatory and systemic autoimmune disease resulting in severe joint destruction, lifelong suffering and considerable disability. Diverse prescriptions of traditional Chinese medicine (TCM) containing Epimedii Herba (EH) achieve greatly curative effects against RA. The present review aims to systemically summarize the therapeutic effect, pharmacological mechanism, bioavailability and safety assessment of EH to provide a novel insight for subsequent studies. The search terms included were "Epimedii Herba", "yinyanghuo", "arthritis, rheumatoid" and "Rheumatoid Arthritis", and relevant literatures were collected on the database such as Google Scholar, Pubmed, Web of Science and CNKI. In this review, 15 compounds from EH for the treatment of RA were summarized from the aspects of anti-inflammatory, immunoregulatory, cartilage and bone protective, antiangiogenic and antioxidant activities. Although EH has been frequently used to treat RA in clinical practice, studies on mechanisms of these activities are still scarce. Various compounds of EH have the multifunctional traits in the treatment of RA, so EH may be a great complementary medicine option and it is necessary to pay more attention to further research and development.

Resveratrol biotransformation and actions on the liver metabolism of healthy and arthritic rats

AIMS

To investigate the effects of resveratrol on glycogen catabolism and gluconeogenesis in perfused livers of healthy and arthritic rats. The actions of resveratrol-3-O-glucuronide (R3G) and the biotransformation of resveratrol into R3G was further evaluated in the livers.

MAIN METHODS

arthritis was induced with Freund's adjuvant. Resveratrol at concentrations of 10, 25, 50, 100 and 200 μM and 200 μM R3G were introduced in perfused livers. Resveratrol and metabolites were measured in the outflowing perfusate. Respiration of isolated mitochondria and activity of gluconeogenic enzymes were also evaluated in the livers.

KEY FINDINGS

resveratrol inhibited glycogen catabolism when infused at concentrations above 50 μM and gluconeogenesis even at 10 μM in both healthy and arthritic rat livers, but more sensitive in these latter. Resveratrol above 100 μM inhibited ADP-stimulated respiration and the activities of NADH- and succinate-oxidases in mitochondria, which were partially responsible for gluconeogenesis inhibition. Pyruvate carboxylase activity was inhibited by 25 μM resveratrol and should inhibit gluconeogenesis already at low concentrations. Resveratrol was significantly metabolized to R3G in healthy rat livers, however, R3G formation was lower in arthritic rat livers. The latter must be in part a consequence of a lower glucose disposal for glucuronidation. When compared to resveratrol, R3G inhibited gluconeogenesis in a lower extension and glycogen catabolism in a higher extension.

SIGNIFICANCE

the effects of resveratrol and R3G tended to be transitory and existed only when the resveratrol is present in the organ, however, they should be considered because significant serum concentrations of both are found after oral ingestion of resveratrol.

Pectin Microspheres: Synthesis Methods, Properties, and Their Multidisciplinary Applications

There is great contemporary interest in using cleaner technologies through green chemistry and utilizing biopolymers as raw material. Pectin is found on plant cell walls, and it is commonly extracted from fruit shells, mostly apples or citrus fruits. Pectin has applications in many areas of commercial relevance; for this reason, it is possible to find available information about novel methods to transform pectin and pursuing enhanced features, with the structuring of biopolymer microspheres being highly cited to enhance its activity. The structuring of polymers is a technique that has been growing in recent decades, due to its potential for diverse applications in various fields of science and technology. Several techniques are used for the synthesis of microspheres, such as ionotropic gelation, extrusion, aerosol drying, or emulsions, with the latter being the most commonly used method based on its reproducibility and simplicity. The most cited applications are in drug delivery, especially for the treatment of colon diseases and digestive-tract-related issues. In the industrial field, it is used for protecting encapsulated compounds; moreover, the environmental applications mainly include the bioremediation of toxic substances. However, there are still many possibilities for expanding the use of this biopolymer in the environmental field.

Alpha-tocopherol-loaded polycaprolactone nanoparticles improve the inflammation and systemic oxidative stress of arthritic rats

Background and aim

The present study investigated the effects of orally administered α-tocopherol-loaded polycaprolactone nanoparticles on the articular inflammation and systemic oxidative status of middle-aged Holtzman rats with Freund's adjuvant-induced polyarthritis, a model for rheumatoid arthritis. Intraperitoneally administered free α-tocopherol provided the reference for comparison.

Experimental procedure

Two protocols of treatment were followed: intraperitoneal administration of free α-tocopherol (100 mg/kg i.p.) or oral administration of free and nanoencapsulated α-tocopherol (100 mg/kg p.o.). Animals were treated during 18 days after arthritis induction.

Results

Free (i.p.) and encapsulated α-tocopherol decreased the hind paws edema, the leukocytes infiltration into femorotibial joints and the mRNA expression of pro-inflammatory cytokines in the tibial anterior muscle of arthritic rats, but the encapsulated compound was more effective. Free (i.p.) and encapsulated α-tocopherol decreased the high levels of reactive oxygen species in the brain and liver, but only the encapsulated compound decreased the levels of protein carbonyl groups in these organs. Both free (i.p.) and encapsulated α-tocopherol increased the α-tocopherol levels and the ratio of reduced to oxidized glutathione in these organs.

Conclusion

Both intraperitoneally administered free α-tocopherol and orally administered encapsulated α-tocopherol effectively improved inflammation and systemic oxidative stress in middle-aged arthritic rats. However, the encapsulated form should be preferred because the oral administration route does not be linked to the evident discomfort that is caused in general by injectable medicaments. Consequently, α-tocopherol-loaded polycaprolactone nanoparticles may be a promising adjuvant to the most current approaches aiming at rheumatoid arthritis therapy.

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Oxidative stress is systemically increased in rats with adjuvant-induced arthritis.

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Arthritic rats were orally treated with α-tocopherol-loaded polycaprolactone nanoparticles.

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Treatment decreased the paw edema and articular inflammation of arthritic rats.

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Treatment improved the oxidative stress in the liver and brain arthritic rats.

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The content of α-tocopherol was increased in the brain and liver of treated rats.