Protective Effect of Baicalin Against TLR4-mediated UVA-induced Skin Inflammation

Topical Application of Baicalin Combined with Echinacoside Ameliorates Psoriatic Skin Lesions by Suppressing the Inflammation-Related TNF Signaling Pathway and the Angiogenesis-Related VEGF Signaling Pathway

Baicalin (BAI), the main active component of Scutellaria baicalensis, has significant anti-inflammatory and antibacterial effects. Echinacoside (ECH), an active component from Echinacea purpurea, has significant antiangiogenesis and antioxidant effects. In previous studies, BAI or ECH has been used for some skin inflammation problems by topical treatment. Psoriasis (PSO) is a common inflammatory skin disease with typical features such as excessive inflammatory response and vascular proliferation in skin lesions. Because of the anti-inflammatory effect of BAI and the antiangiogenic activity of ECH, it is proposed that the combination of BAI and ECH can ameliorate psoriatic skin lesions better than a single component. This study aims to explore the effects and potential mechanisms of BAI combined with ECH on imiquimod (IMQ)-induced psoriatic skin lesions by topical treatment. Transcriptome analysis first showed that the TNF signaling pathway and the VEGF signaling pathway were significantly enriched in IMQ-induced psoriatic skin lesions. Topical application of BAI combined with ECH could ameliorate IMQ-induced skin lesions in mice, especially the better effects of B2-E1 (BAI/ECH = 2:1). Network pharmacology analysis and molecular docking indicated that BAI-treated PSO on the skin by regulating the TNF signaling pathway, and ECH treated PSO on the skin by regulating the VEGF signaling pathway. Meanwhile, the ELISA test and the qPCR assay showed that BAI combined with ECH could inhibit the expression of key cytokines and genes related to the TNF signaling pathway and the VEGF signaling pathway. Zebrafish experiments demonstrated the anti-inflammatory and antiangiogenic effects of BAI combined with ECH and revealed the potential mechanisms associated with regulating the inflammation-related TNF signaling pathway and the angiogenesis-related VEGF signaling pathway. This suggested that BAI combined with ECH may be a promising topical agent to ameliorate psoriatic skin lesions in the future.

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.

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.

Flavonoids Present in Propolis in the Battle against Photoaging and Psoriasis

The skin is the main external organ. It protects against different types of potentially harmful agents, such as pathogens, or physical factors, such as radiation. Skin disorders are very diverse, and some of them lack adequate and accessible treatment. The photoaging of the skin is a problem of great relevance since it is related to the development of cancer, while psoriasis is a chronic inflammatory disease that causes scaly skin lesions and deterioration of the lifestyle of people affected. These diseases affect the patient's health and quality of life, so alternatives have been sought that improve the treatment for these diseases. This review focuses on describing the properties and benefits of flavonoids from propolis against these diseases. The information collected shows that the antioxidant and anti-inflammatory properties of flavonoids play a crucial role in the control and regulation of the cellular and biochemical alterations caused by these diseases; moreover, flavones, flavonols, flavanones, flavan-3-ols, and isoflavones contained in different worldwide propolis samples are the types of flavonoids usually evaluated in both diseases. Therefore, the research carried out in the area of dermatology with bioactive compounds of different origins is of great relevance to developing preventive and therapeutic approaches.

Flavonoids against non-physiologic inflammation attributed to cancer initiation, development, and progression—3PM pathways

Inflammation is an essential pillar of the immune defense. On the other hand, chronic inflammation is considered a hallmark of cancer initiation and progression. Chronic inflammation demonstrates a potential to induce complex changes at molecular, cellular, and organ levels including but not restricted to the stagnation and impairment of healing processes, uncontrolled production of aggressive ROS/RNS, triggered DNA mutations and damage, compromised efficacy of the DNA repair machinery, significantly upregulated cytokine/chemokine release and associated patho-physiologic protein synthesis, activated signaling pathways involved in carcinogenesis and tumor progression, abnormal tissue remodeling, and created pre-metastatic niches, among others. The anti-inflammatory activities of flavonoids demonstrate clinically relevant potential as preventive and therapeutic agents to improve individual outcomes in diseases linked to the low-grade systemic and chronic inflammation, including cancers. To this end, flavonoids are potent modulators of pro-inflammatory gene expression being, therefore, of great interest as agents selectively suppressing molecular targets within pro-inflammatory pathways. This paper provides in-depth analysis of anti-inflammatory properties of flavonoids, highlights corresponding mechanisms and targeted molecular pathways, and proposes potential treatment models for multi-level cancer prevention in the framework of predictive, preventive, and personalized medicine (PPPM / 3PM). To this end, individualized profiling and patient stratification are essential for implementing targeted anti-inflammatory approaches. Most prominent examples are presented for the proposed application of flavonoid-conducted anti-inflammatory treatments in overall cancer management.

Study on multiple fingerprint profiles control and quantitative analysis of multi-components by single marker method combined with chemometrics based on Yankening tablets

In this study, we explored the quality consistent evaluation method of Yankening Tablets (YKNT) from different manufacturers by using multiple fingerprint profiles, including dual-wavelength ultra-high performance liquid chromatography (UPLC) serial fingerprint and Fourier Transform Infrared Spectroscopy (FT-IR) fingerprint, combined with quantitative analysis of multi-components by single marker (QAMS) method. In the Average method of systematic quantified fingerprint method (AMSQFM), three fingerprint parameters of macro qualitative similarity (S_m-UPLC-FTIR), macro quantitative similarity (P_m-UPLC-FTIR), and the variation coefficient of fingerprint homogeneity (α_UPLC-FTIR) were calculated based on the ratio method. The S_m-UPLC-FTIR values of all the samples were greater than 0.80, the α_UPLC-FTIR values were less than 0.20, and the P_m-UPLC-FTIR values range from 72.8% to 119.8%. Method validation results showed the established fingerprint method had good precision, solution stability, and method repeatability, all samples could be roughly divided into different levels. The contents of berberine (BBR) and baicalin (BCL) measured by the calibration curve method (CCM) and QAMS method were compared, and t-test results (Pvalue > 0.05) indicated there was no significant difference between the two methods, which showed that QAMS could accurately quantify the markers of the YKNT. The explanatory ability (R²Y) values of BBR and BCL in the PLS model were both greater than 0.94, and the root mean square error of estimation (RMSEE) and root mean square error of prediction (RMSEP) values were both less than 2.5, indicating that the established model was reliable. Hierarchical cluster analysis divided all samples into four categories. This research made a major contribution to the quality consistent evaluation of Traditional Chinese Medicine (TCM) and food.

Baicalin ameliorates Mycoplasma gallisepticum-induced lung inflammation in chicken by inhibiting TLR6-mediated NF-κB signalling

1. Mycoplasma gallisepticum (MG) causes severe lung inflammation and cell damage by activating toll-like receptor (TLR) signalling, the nuclear factor-kappaB (NF-κB) pathway and pro-inflammatory cytokine gene expression. Baicalin (BA) is a flavonoid extracted from Scutellaria baicalensis, which possesses anti-inflammatory and anti-bacterial properties. This study investigated the effect of BA in MG-induced lung inflammation and its potential mechanism in MG-infected chicken embryo lungs and DF-1 cells.2. The histopathological examination result showed that BA treatment alleviated MG-induced lung pathological changes. In addition, CCK-8 and cell cycle assays showed that BA treatment inhibited MG-induced cell proliferation and cell cycle progression in DF-1 cells.3. The ELISA and RT-qPCR results demonstrated that BA treatment decreased the expression of interleukin-1beta (IL-1β), IL-6, and tumour necrosis factor-alpha (TNF-α) both in MG-infected chicken embryo lungs and DF-1 cells.4. The results revealed that BA inhibited mRNA expression levels of toll-like receptor-6 (TLR6), myeloid differentiation primary response gene-88 (MyD88) and nuclear factor-κB (NF-κB), and the nuclear translocation of NF-κB-p655. In conclusion, the results showed that BA has a protective effect against MG-induced lung inflammation in chicken by inhibiting the TLR6-mediated NF-κB signalling.

Skin photo-protection with phytochemicals against photo-oxidative stress, photo-carcinogenesis, signal transduction pathways and extracellular matrix remodeling-An overview

Excessive exposure of skin to UV radiation triggers the generation of oxidative stress, inflammation, immunosuppression, apoptosis, matrix-metalloproteases production, and DNA mutations leading to the onset of photo ageing and photo-carcinogenesis. At the molecular level, these changes occur via activation of several protein kinases as well as transcription pathways, formation of reactive oxygen species, and release of cytokines, interleukins and prostaglandins together. Current therapies available on the market only provide limited solutions and exhibit several side effects. The present paper provides insight into scientific studies that have elucidated the positive role of phytochemicals in counteracting the UV-induced depletion of antioxidant enzymes, increased lipid peroxidation, inflammation, DNA mutations, increased senescence, dysfunctional apoptosis and immune suppression. The contribution of phytochemicals to the downregulation of expression of oxidative-stress sensitive transcription factors (Nrf2, NF-Kb, AP-1 and p53) and protein kinases (MSK, ERK, JNK, p38 MAPK, p90RSK2 and CaMKs) involved in inflammation, apoptosis, immune suppression, extracellular matrix remodelling, senescence, photo ageing and photo-carcinogenesis, is also discussed. Conclusively, several phytochemicals hold potential for the development of a viable solution against UV irradiation-mediated photo ageing, photo-carcinogenesis and related manifestations.

Immunological regulatory effect of flavonoid baicalin on innate immune toll-like receptors

As an essential component of the innate immune system, Toll-like receptors (TLRs) are a family of well-recognized ligand-binding receptors found in various organisms and initiate host immune responses. Activation of TLRs signaling pathways lead to the induction of numerous genes that function in host defense. Baicalin is a natural compound from the dry raw root of Scutellaria baicalensis (S. baicalensis) and it has been found to exhibit several pharmaceutical actions, such as anti-inflammation, anti-tumor and antivirus. These biological activities are mainly related to the regulatory effect of baicalin on the host immune response. In this review, we provide an overview of the regulation of baicalin on TLRs signaling pathways in various pathological conditions, and highlight potential targets for the development of the regulatory effect of natural compound from traditional Chinese medicine on innate immune system.

Anti-inflammatory effect of paeoniflorin combined with baicalin in oral inflammatory diseases

OBJECTIVE

There are challenges in the treatment of chronic inflammatory diseases of oral mucosa. Both paeoniflorin (PF) and baicalin (BAI) exert anti-inflammatory effects, but the mechanism underlying their combined effects is still unclear. Here, we explored the anti-inflammatory function of the PF-BAI combination in the oral inflammatory response.

MATERIALS AND METHODS

The CCK-8 assay was used to determine the proliferative capacity of HOKs with PF and BAI. Enzyme-linked immunosorbent (ELISA), Western blotting, reverse transcription polymerase chain reaction, and confocal immunofluorescence were performed to study the anti-inflammatory effects of PF-BAI in LPS-stimulated human oral keratinocytes (HOKs). Immunohistochemistry and ELISA were performed to detect the levels of NF-κB p65, IKKα and IL-6, TNF-α in OLP and healthy tissues.

RESULTS

Compared to PF or BAI alone, the combination of PF-BAI at 5 µg/ml downregulated secretion of inflammatory cytokines more effectively (p < .05). Combined PF-BAI decreased NF-κB p65 and IκBα protein phosphorylation, leading to reduce nuclear translocation of NF-κB p65. Higher expression of TNF-α, IL-6, NF-κB p65, and IKKα were observed in OLP than in HC tissues (p < .01).

CONCLUSION

The optimal combination concentration of PF and BAI at 5 µg/ml may have a positive effect on the treatment of oral inflammatory diseases, providing a novel therapeutic approach.

TLR4 in skin cancer: From molecular mechanisms to clinical interventions

The health and economic burden imposed by skin cancer is substantial, creating an urgent need for the development of improved molecular strategies for its prevention and treatment. Cutaneous exposure to solar ultraviolet (UV) radiation is a causative factor in skin carcinogenesis, and TLR4-dependent inflammatory dysregulation is an emerging key mechanism underlying detrimental effects of acute and chronic UV exposure. Direct and indirect TLR4 activation, upstream of inflammatory signaling, is elicited by a variety of stimuli, including pathogen-associated molecular patterns (such as lipopolysaccharide) and damage-associated molecular patterns (such as HMGB1) that are formed upon exposure to environmental stressors, such as solar UV. TLR4 involvement has now been implicated in major types of skin malignancies, including nonmelanoma skin cancer, melanoma and Merkel cell carcinoma. Targeted molecular interventions that positively or negatively modulate TLR4 signaling have shown promise in translational, preclinical, and clinical investigations that may benefit skin cancer patients in the near future.

Baicalin Weakens Staphylococcus aureus Pathogenicity by Targeting Sortase B

Staphylococcus aureus (S. aureus) is a human and other animal pathogen that contributes to the primary etiology of nosocomial pneumonia, a disease with high mortality rates and costs. Treatment of multidrug-resistant S. aureus infection is extremely challenging, and new therapeutic strategies beyond antibiotic treatment are needed. Anti-virulence agents that specifically target the molecular determinants of virulence may be a novel method for treating drug-resistant nosocomial infections. Sortase B (SrtB) is a crucial virulence factor in S. aureus and plays an important role during infection. In this study, we find that baicalin suppresses the activity of SrtB. Minimum inhibitory concentration and growth curve assays confirmed that baicalin has no anti-S. aureus properties. We performed live/dead, lactate dehydrogenase (LDH), adherence, and enzyme-linked immunosorbent assays to confirm that baicalin reduced human alveolar epithelial A549 cell injury caused by S. aureus, reduced the adherence of S. aureus to A549 cells, and significantly attenuated the inflammatory response of mouse macrophage J774 cells to S. aureus. Additionally, we were able to elucidate the binding mechanics and identify the interacting sites of baicalin and SrtB via a molecular dynamics simulation, site-directed mutagenesis, and fluorescence spectroscopy quenching. Finally, we confirmed that baicalin directly binds to the active center of SrtB, and the residues Asn⁹² and Tyr¹²⁸ perform an important function in the interaction of SrtB and baicalin. Taken together, these data indicate that baicalin is a promising candidate to combat S. aureus infections.