Tannic acid, a higher galloylated pentagalloylglucose, suppresses antigen-specific IgE production by inhibiting ɛ germline transcription induced by STAT6 activation

Screening and characterization of xenobiotics in rat bio-samples after oral administration of Shen-Wu-Yi-Shen tablet using UPLC-Q-TOF-MS/MS combined with a targeted and non-targeted strategy

Shen-Wu-Yi-Shen tablet (SWYST), a well-known traditional Chinese medicine prescription (TCMP), has been effectively used for treating chronic kidney disease (CKD) in clinically. However, an in-depth study of in vivo metabolism of SWYST is lacking. In this study, a targeted and non-targeted strategy based on ultra-performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry (UPLC-Q-TOF-MS/MS) was developed to screen and characterize SWYST-related xenobiotics in rats. Based on the in-house library, a chemical database of SWYST including 215 constituents was constructed through "find by formula" and further verified by characteristic fragmentations or the literatures. Then the constructed chemical database was applied for the targeted screening of prototypes. As for metabolites, the non-targeted screening was achieved combined the peak picking using the function "find by auto-MS/MS" and peak filtration of the prototypes and endogenous components, while the targeted screening was performed using Metabolite ID according to the possible metabolic reactions. Furthermore, the potential metabolites were preliminarily identified by comparison of the parent compounds or references to the literatures. As a result, 201 exogenous components (87 prototypes and 121 metabolites) were characterized in rats after administration of SWYST, including 55 (17 prototypes and 38 metabolites) in plasma, 151 (52 prototypes and 99 metabolites) in urine, and 121 (74 prototypes and 47 metabolites) in feces. Finally, their possible metabolic pathways were summarized, and the metabolic reactions mainly involved phase I reactions (hydroxylation, deoxygenation, hydrogenation, methylation, oxidation, hydrolysis and esterification) and phase II reactions (glucuronidation and sulfation). The findings of this research reveal the potential active ingredients of SWYST, providing an important material basis for the pharmacokinetics and pharmacodynamics of SWYST.

Hydrolyzable Tannins in the Management of Th1, Th2 and Th17 Inflammatory-Related Diseases

Plants rich in hydrolyzable tannins were traditionally used all over the world for a variety of chronic inflammatory disorders, including arthritis, colitis, and dermatitis. However, the knowledge of their immunological targets is still limited though fundamental for their rational use in phytotherapy. The recent advances regarding the pathogenesis of inflammatory-based diseases represent an opportunity to elucidate the pharmacological mechanism of plant-derived metabolites with immunomodulatory activity. This review collects recent articles regarding the role of hydrolyzable tannins and their gut metabolites in Th1, Th2, and Th17 inflammatory responses. In line with the traditional use, rheumatoid arthritis (RA), inflammatory bowel diseases (IBDs), psoriasis, atopic dermatitis (AD), and asthma were the most investigated diseases. A substantial body of in vivo studies suggests that, beside innate response, hydrolyzable tannins may reduce the levels of Th-derived cytokines, including IFN-γ, IL-17, and IL-4, following oral administration. The mode of action is multitarget and may involve the impairment of inflammatory transcription factors (NF-κB, NFAT, STAT), enzymes (MAPKs, COX-2, iNOS), and ion channels. However, their potential impact on pathways with renewed interest for inflammation, such as JAK/STAT, or the modulation of the gut microbiota demands dedicate studies.

Unveiling the Ability of Witch Hazel (Hamamelis virginiana L.) Bark Extract to Impair Keratinocyte Inflammatory Cascade Typical of Atopic Eczema

Hamamelis virginiana L. bark extract is a traditional remedy for skin affections, including atopic dermatitis/eczema (AD). Hamamelis preparations contain tannins, including hamamelitannin (HT), although their pharmacological role in AD is still unknown. This study aimed to study the rational for its topical use by considering the impact of crucial biomarkers on AD pathogenesis. A standardized extract (HVE) (0.5−125 μg/mL) was compared to hamamelitannin (HT), its main compound (0.5−5 μg/mL), in a model of human keratinocytes (HaCaTs), challenged with an AD-like cytokine milieu (TNF-α, IFN-γ, and IL-4). HVE inhibited the release of mediators involved in skin autoimmunity (IL-6 and IL-17C) and allergy (TSLP, IL-6, CCL26, and MMP-9) with a concentration-dependent fashion (IC50s < 25 μg/mL). The biological mechanism was ascribed, at least in part, to the impairment of the NF-κB-driven transcription. Moreover, HVE counteracted the proliferative effects of IL-4 and recovered K10, a marker of skin differentiation. Notably, HT showed activity on well-known targets of IL-4 pathway (CCL26, K10, cell proliferation). To the best of our knowledge, this work represents the first demonstration of the potential role of Hamamelis virginiana in the control of AD symptoms, such as itch and skin barrier impairment, supporting the relevance of the whole phytocomplex.

Co-Application with Tannic Acid Prevents Transdermal Sensitization to Ovalbumin in Mice

Transdermal sensitization to allergens is of great concern as a sensitization route for food allergies. This skin-mediated invasion and sensitization to allergens is involved in skin barrier breakdown and inflammation, followed by the production of several kinds of cytokines. Cytokines such as thymic stromal lymphopoietin and thymus and activation-regulated chemokine are also involved. In this study, we investigated the suppressive effect of tannic acid (TA) on transdermal sensitization using ovalbumin (OVA), a major egg-white allergen. We also analyzed the mechanisms associated with the inhibitory effects of TA. The results showed that the co-application with TA prevents transdermal sensitization to OVA. As possible mechanisms, its anti-inflammatory and astringent effect on the skin and binding ability with the protein were considered. These results indicate that TA could be applied to cosmetics and lotions, which could suppress the transdermal sensitization to allergens.

Medicinal Importance, Pharmacological Activities, and Analytical Aspects of Strictinin: A Mini-Review

BACKGROUND

Plants and their derived products have been used in history as food and medicine. Plant materials are rich sources of fiber, minerals, vitamins, and bioactive phytochemicals, which are useful for human beings. Strictinin is an important phytoconstituent of green tea.

METHODS

Present work mainly focuses on the biological importance, therapeutic potential, and pharmacological activities of strictinin in medicine. Numerous scientific data have been collected from various literature databases such as Google Scholar, Science Direct, PubMed, and Scopus database in order to realize the health beneficial potential of strictinin. Pharmacological data has been collected and analyzed in the present work to find the effectiveness of strictinin against human disorders and complications. Analytical data of strictinin has been also collected and analyzed in the present work.

RESULTS

Scientific data analysis revealed the biological importance of strictinin in medicine. Scientific data analysis signified the therapeutic benefit of strictinin mainly due to its anticancer, antimicrobial, antibacterial, antiviral, and antioxidant activity. However, enzymatic activities, cytotoxicity, effectiveness on skin disorders, and osteogenic potential of strictinin have also been discussed. Analytical data revealed the importance of modern analytical techniques in medicine for the separation, identification, and isolation of strictinin.

CONCLUSION

Present work signified the biological importance and therapeutic benefits of strictinin in medicine and other allied health sectors.

Tertiary lymphoid structure related B-cell IgE isotype switching and secondary lymphoid organ linked IgE production in mouse allergy model

Background

Numerous data obtained by different research laboratories indicate that specific IgE production is triggered independently of specific IgG or IgA ones and so it is not linked to fully matured germinal centers formation in the secondary lymphoid organs. The aim of this study was to clarify whether specific IgE production is triggered by low antigen doses administrated in tertiary tissues enriched by lymphoid structures.

Methods

Ovalbumin (OVA) in different doses (100 ng to 10 μg) was administrated three times a week for 4–5 weeks intraperitoneally (i.p.) or subcutaneously (s.c.) to female BALB/c mice in the wither region which is enriched in fat-associated lymphoid clusters or in the foot pad region not containing them.

Results

OVA-specific IgE was predominantly induced by low but not high antigen doses and only after immunization into the withers. IgE isotype switching was triggered exclusively in the withers adipose tissue but not in the regional lymph nodes while mature IgE expressing cells were observed both in the withers and lymph nodes. Anti-proliferative genotoxic stress inducing drugs shifted the balance from IgG1 towards IgE production.

Conclusions

Tertiary lymphoid structures possess unique environment where B-cell antibody isotype switching to IgE predominantly occurs. This phenomenon is partially explained by hampered proliferation of B-cells in these structures.

Pentagalloyl Glucose and Its Functional Role in Vascular Health: Biomechanics and Drug-Delivery Characteristics

Pentagalloyl glucose (PGG) is an elastin-stabilizing polyphenolic compound that has significant biomedical benefits, such as being a free radical sink, an anti-inflammatory agent, anti-diabetic agent, enzymatic resistant properties, etc. This review article focuses on the important benefits of PGG on vascular health, including its role in tissue mechanics, the different modes of pharmacological administration (e.g., oral, intravenous and endovascular route, intraperitoneal route, subcutaneous route, and nanoparticle based delivery and microbubble-based delivery), and its potential therapeutic role in vascular diseases such as abdominal aortic aneurysms (AAA). In particular, the use of PGG for AAA suppression and prevention has been demonstrated to be effective only in the calcium chloride rat AAA model. Therefore, in this critical review we address the challenges that lie ahead for the clinical translation of PGG as an AAA growth suppressor.

Tannic Acid Cross-linked Polysaccharide-Based Multifunctional Hemostatic Microparticles for the Regulation of Rapid Wound Healing

Hemostatic microparticles (HMs) have been widely used in surgery. To improve the comprehensive performance of HMs, multifunctional HMs named HM₁₅ and HM₁₅ ' are prepared from starch, carboxymethyl chitosan, hyaluronic acid, and tannic acid. Herein, tannic acid is used as an effective cross-linker. A 3D network structure for cell growth and wound repair can be formed by secondary cross-linking. Through synergistic effect of these natural materials, the process of wound healing can be regulated controllably. HM₁₅ and HM₁₅ ' have the ability of rapid hemostasis. Moreover, HM₁₅ ' shows excellent properties in antibacteria and wound healing acceleration. Blood clotting time treated with different HMs is shortened obviously from 436.8 s to 126 s. Compared with Celox, HM₁₅ and HM₁₅ ' exhibited better broad spectrum antibacterial activity against both Escherichia coli and Staphylococcus aureus. Notably, the wound can be repaired rapidly by HM₁₅ ' in 14 days. These multifunctional HMs might have an important prospect in clinical application.

Inherently antioxidant and antimicrobial tannic acid release from poly(tannic acid) nanoparticles with controllable degradability

From a natural polyphenol, Tannic acid (TA), poly(TA) nanoparticles were readily prepared using a single step approach with three different biocompatible crosslinkers; trimethylolpropane triglycidyl ether (TMPGDE), poly(ethylene glycol) diglycidyl ether (PEGGE), and trisodium trimetaphosphate (STMP). P(TA) particles were obtained with controllable diameters between 400 to 800nm with -25mV surface charge. The effect of synthesis conditions, such as the emulsion medium, pH values of TA solution, and the type of crosslinker, on the shape, size, dispersity, yield, and degradability of poly(Tannic Acid) (p(TA)) nanoparticles was systematically investigated. The hydrolytic degradation amount in physiological pH conditions of 5.4, 7.4, and 9.0 at 37.5°C were found to be in the order TMPGDE<PEGGE<STMP. Furthermore, the degradation amounts of TA from p(TA) nanoparticles can be controlled by the appropriate choice of crosslinker, and the pH of releasing media. The highest TA release, 600mg/g, was obtained for TMPGDE-crosslinked p(TA) particles in intestinal pH conditions (pH 9) over 3 days; whereas, a slow and linear TA release profile over almost 30 days was obtained by using PEGGE-crosslinked p(TA) in body fluid pH conditions (pH 7.4). The total phenol content of p(TA) particles was calculated as 70±1μgmL(-1) for 170μgmL(-1) p(TA), and the trolox equivalent antioxidant capacity was found to be 2027±104mM trolox equivalent g(-1). Moreover, p(TA) nanoparticles demonstrated strong antimicrobial effects against common bacterial strains. More interestingly, with a higher concentration of p(TA) particles, higher blood clotting indices were obtained.

IL-4 receptor α in non-lipid rafts is the target molecule of strictinin in inhibiting STAT6 activation

Strictinin has been shown to suppress interleukin (IL)-4-induced signal transducer and activator of transcription (STAT)-6 phosphorylation, which is a critical event for IgE class switching. However, it is unclear how strictinin inhibits STAT6 activation. Strictinin inhibited STAT6 phosphorylation by suppressing IL-4 receptor α (IL-4Rα) activation. Strictinin was bound to the cell surface and only localized in non-lipid raft fraction of the cells where IL-4Rα was also located. In addition, strictinin directly bound to IL-4Rα and inhibited binding of IL-4 to IL-4Rα. These results suggest that IL-4Rα locating in non-lipid raft region is a target molecule for strictinin in inhibiting STAT6 activation.