Baicalin promotes antiviral IFNs production and alleviates type I IFN-induced neutrophil inflammation

Baicalin Modulates Glycolysis via the PKC/Raf/MEK/ERK and PI3K/AKT Signaling Pathways to Attenuate IFN-I-Induced Neutrophil NETosis

Type I interferon (IFN-I), a pivotal component of the host's innate antiviral immune system, can induce the formation of neutrophil extracellular traps (NETs) and facilitate inflammatory responses. Baicalin exhibits a range of pharmacological activities, including anti-inflammatory and immunomodulatory effects. It has been reported that neutrophil glycolysis plays a pivotal role in the formation of NETs and the regulation of inflammatory response in immune modulation, regulated by IFN-I. However, it remains unclear whether baicalin regulates IFN-I-induced NETs formation through glycolysis. In this study, we induced the formation of NETs in vitro using IFN-I and observed that baicalin significantly reduced the formation of IFN-I-induced NETs. Furthermore, baicalin inhibited the production of pro-inflammatory cytokines, specifically interleukin-1 beta (IL-1β) and interleukin-6 (IL-6), as well as the generation of reactive oxygen species (ROS) and chemotactic responses. Our findings further indicated that baicalin could inhibit both lactic acid and ATP levels in IFN-I-induced neutrophils, as well as the expression of glycolytic-related proteins, including HK2, HK3, PKM2, and LDHA. Moreover, following the administration of glycolytic agonists insulin, it was observed that heightened glycolytic activity significantly augmented NETs formation and the release of inflammatory cytokines, potentially regulated by PKC/Raf/MEK/ERK and PI3K/AKT signaling pathways. In conclusion, our findings indicated that baicalin may exert inhibitory effects on IFN-I-induced NETs formation and inflammatory cytokine production by modulating glycolysis, thereby providing further evidence for the potential clinical application of baicalin in the treatment of IFN-I-related inflammatory diseases.

Interferon-I modulation and natural products: Unraveling mechanisms and therapeutic potential in severe COVID-19

The coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continues to pose a significant global public health threat, particularly to older adults, pregnant women, and individuals with underlying chronic conditions. Dysregulated immune responses to SARS-CoV-2 infection are believed to contribute to the progression of COVID-19 in severe cases. Previous studies indicates that a deficiency in type I interferon (IFN-I) immunity accounts for approximately 15 %-20 % of patients with severe pneumonia caused by COVID-19, highlighting the potential therapeutic importance of modulating IFN-I signals. Natural products and their derivatives, due to their structural diversity and novel scaffolds, play a crucial role in drug discovery. Some of these natural products targeting IFN-I have demonstrated applications in infectious diseases and inflammatory conditions. However, the immunomodulatory potential of IFN-I in critical COVID-19 pneumonia and the natural compounds regulating the related signal pathway remain not fully understood. In this review, we offer a comprehensive assessment of the association between IFN-I and severe COVID-19, exploring its mechanisms and integrating information on natural compounds effective for IFN-I regulation. Focusing on the primary targets of IFN-I, we also summarize the regulatory mechanisms of natural products, their impact on IFNs, and their therapeutic roles in viral infections. Collectively, by synthesizing these findings, our goal is to provide a valuable reference for future research and to inspire innovative treatment strategies for COVID-19.

Biological effects of baicalin on the ovine mammary cells and regulatory mechanism study by transcriptomic analysis

Baicalin is a natural flavonoid compound with a wide range of biological activities, including anti-oxidant and anti-inflammatory properties. Previous we found that the abundance of baicalin in bovine serum is significantly higher than in ovine serum at mid-lactation. It suggests that baicalin may play a role in the regulation of lactation performance. Here, the biological effects of baicalin on proliferative, oxidative stress response, synthesis capacities of major milk components of ovine mammary epithelial cells (OMECs) were investigated. And the transcriptomic analysis was utilized to explore the possible regulatory mechanism. Results showed that 25 μg/mL baicalin can significantly enhance the proliferation, antioxidant, triglyceride and lactose synthesis capacities of OMECs. In transcriptomic analysis, 150 differentially expressed genes (DEGs) were screened between 25 μM baicalin treated (Baicalin) and 0 μM baicalin treated (NT) groups. Functional analysis of DEGs showed that lipid metabolic process, response to oxidative stress, biosynthesis of fat and saccharide pathways were enriched. qRT-PCR result showed that antioxidation-related negative regulatory gene MPO was significantly down-regulated and milk fat biosynthesis related genes PLA2G12A, GPCPD1, LPIN1, FASN and lactose biosynthesis related genes MGEA5, RHOQ were significantly up-regulated in baicalin treated OMECs (P < 0.01). In summarize, 25 μM baicalin can significantly enhance the proliferation, antioxidant and biosynthesis of milk fat and lactose capacities through lipid metabolic process, response to oxidative stress, biosynthesis of fat and saccharide pathways related genes regulation in OMECs. The study would provide a theoretical basis for the improvement of lactation performance and the exploration of lactation regulation theory of dairy sheep.

Discovering the Q-marker of scutellaria baicalensis against viral pneumonia integrated chemical profile identification, pharmacokinetic, metabolomics and network pharmacology

ETHNOPHARMACOLOGICAL RELEVANCE

Scutellaria baicalensis (SR), an ancient antiviral herbal medicine, is widely used in treating viral pneumonia and its active constituents, baicalin and baicalein, have been reported to have antiviral activity.

AIM OF THE STUDY

However, reports on Q-markers of SR for antiviral pneumonia are still scarce. This study aims to screen for Q-markers using a comprehensive strategy that integrates identification of chemical profiles, in vivo absorption, metabolic regulation and predicted target.

MATERIALS AND METHODS

First, the markers were screened by chemical profile identification and pharmacokinetics using HPLC-MS/MS. Then, the therapeutic effects and differential metabolites of SR on viral pneumonia rats were evaluated by HE staining, assessment of inflammation levels and metabolomics analysis. Finally, the mechanisms of action between Q-markers and metabolites were exploited based on network pharmacology.

CONCLUSION

A total of 139 compounds were identified in SR, of which 35 and 41 were found in rat plasma and urine, respectively. Pharmacokinetic screening identified baicalin, baicalein, wogonin, wogonoside and oroxylin A as potential markers of SR. Furthermore, SR significantly improved interstitial and alveolar oedema, hemorrhage and alveolar collapse after modelling, while reducing the expression of inflammatory factors. Metabolomics revealed that SR significantly regulated the expression of 37 metabolites, mainly involving phenylalanine, tyrosine and tryptophan biosynthesis pathways. Network pharmacology showed that these five biomarkers can regulate the expression of metabolites through the key target SRC, ESR1, HSP90AA1, EGFR, thereby exerting antiviral effects against pneumonia. The study results suggest that baicalin, baicalein, wogonin, wogonoside and oroxylin A serve as primary Q-markers of SR in the treatment of viral pneumonia.

Baicalin enhances antioxidant, inflammatory defense, and microbial diversity of yellow catfish (Pelteobagrus fulvidraco) infected with Aeromonas hydrophila

Introduction

The aim of this research was to clarify the mechanism through which baicalin exerts its inhibitory effects on Aeromonas hydrophila infection.

Methods

The antibacterial efficacy of baicalin was assessed by determining its minimum inhibitory concentration (MIC) against A. hydrophila. Various parameters, including the growth curve, cell wall integrity, biofilm formation, AKP content, and morphological alterations of A. hydrophila, were analyzed. In vivo experiments involved the administration of A. hydrophila 4 h postintraperitoneal injection of varying doses of baicalin to induce infection, with subsequent monitoring of mortality rates. After a 3 d period, liver, spleen, and intestinal tissues were harvested to evaluate organ indices, antioxidant and immune parameters, as well as intestinal microbial composition.

Results

The findings indicated that baicalin treatment resulted in the disruption of the cell wall of A. hydrophila, leading to the loss of its normal structural integrity. Furthermore, baicalin significantly inhibited biofilm formation and facilitated the release of intracellular proteins (P < 0.05). In vivo, baicalin enhanced the survival rates of yellow catfish infected with A. hydrophila. Compared to the control group, the liver index of yellow catfish was elevated, while the spleen and intestinal indices were reduced in the baicalin-treated group (P < 0.05). Additionally, baicalin at an appropriate dosage was found to increase levels of SOD, GSH, CAT, ACP, and AKP in yellow catfish (P < 0.05), while simultaneously decreasing MDA accumulation and the mRNA expression of inflammatory markers such as Keap1, IL1, IFN-γ, and TNF-α, (P < 0.05). Moreover, baicalin significantly enhanced the operational taxonomic unit (OTU) count in A. hydrophila-infected yellow catfish (P < 0.05), restoring the abundance of Barnesiellaceae, Enterobacteriaceae, Plesiomonas, and UBA1819 (P < 0.05).

Discussion

In summary, baicalin demonstrates the potential to improve the survival rate of yellow catfish subjected to A. hydrophila infection, augment antioxidant and immune responses, mitigate inflammation, and enhance intestinal microbial diversity.

Baicalin Protects Broilers against Avian Coronavirus Infection via Regulating Respiratory Tract Microbiota and Amino Acid Metabolism

An increasing amount of evidence indicates that Baicalin (Bai, a natural glycosyloxyflavone compound) exhibits an antiviral effect against avian viruses. However, it remains unclear if the antiviral effect of Bai against infectious bronchitis virus (IBV) is exerted indirectly by modulating respiratory tract microbiota and/or their metabolites. In this study, we investigated the protection efficacy of Bai in protecting cell cultures and broilers from IBV infection and assessed modulation of respiratory tract microbiota and metabolites during infection. Bai was administered orally to broilers by being mixed in with drinking water for seven days. Ultimately, broilers were challenged with live IBV. The results showed that Bai treatment reduced respiratory tract symptoms, improved weight gain, slowed histopathological damage, reduced virus loads and decreased pro-inflammation cytokines production. Western blot analysis demonstrated that Bai treatment significantly inhibited Toll-like receptor 7 (TLR7), myeloid differentiation factor 88 (MyD88) and nuclear factor kappa-B (NF-κB) expression both in cell culture and cells of the trachea. Bai treatment reversed respiratory tract microbiota dysbiosis, as shown by 16S rDNA sequencing in the group of broilers inoculated with IBV. Indeed, we observed a decrease in Proteobacteria abundance and an increase in Firmicutes abundance. Metabolomics results suggest that the pentose phosphate pathway, amino acid and nicotinamide metabolism are linked to the protection conferred by Bai against IBV infection. In conclusion, these results indicated that further assessment of anti-IBV strategies based on Bai would likely result in the development of antiviral molecule(s) which can be administered by being mixed with feed or water.

Baicalein alleviates palmitic acid-induced endothelial cell dysfunction via inhibiting endoplasmic reticulum stress

OBJECTIVE

Endothelial cells play a critical role in maintaining vascular function and kinetic homeostasis, but excessive accumulation of palmitic acid (PA) may lead to endoplasmic reticulum stress and trigger endothelial cell dysfunction. Baicalin (BCL), a natural plant extract, has received widespread attention for its biological activities in anti-inflammation and anti-oxidative stress. However, the mechanism of BCL on PA-induced endothelial cell dysfunction is unclear. Therefore, the aim of this study was to investigate whether BCL could inhibit PA-induced endoplasmic reticulum stress and thus attenuate endothelial cell dysfunction.

METHODS

Human umbilical vein endothelial cells (HUVECs) were divided into Control, PA, PA + BCL-10 μM, PA + BCL-20 μM, and PA + BCL-50 μM groups. The PA group was treated with PA (200 μM), while the PA + BCL groups were co-treated with different concentrations of BCL (10 μM, 20 μM, 50 μM) for 24 hours. Cell viability was detected by MTT. Cell migration ability was determined by Transwell assay, apoptosis level by flow cytometry, and tube formation ability by tube formation assay. Finally, the levels of apoptosis-related proteins (Bax, Bcl-2, and cleaved caspase-3) and angiogenesis-related proteins (VEGFA and FGF2) were detected by western blot, MMP-9, as well as the protein levels of endoplasmic reticulum stress biomarkers (GRP78, CHOP, PERK, and ATF4).

RESULTS

The results at the cellular level showed that cell viability, migration ability and tube formation ability of PA-induced HUVECs were significantly reduced, while apoptosis level was significantly increased. However, administration of different concentrations of BCL significantly enhanced PA-induced cell viability, migration ability and tube formation ability of HUVECs while inhibiting apoptosis. The results of protein levels showed that the protein levels of Bax and cleaved caspase-3 were observably up-regulated in the cells of the PA group, while the protein level of Bcl-2 was significantly down-regulated; compared with the PA group, the protein levels of Bax and cleaved caspase-3 were much lower and the Bcl-2 protein level was much higher in the PA + BCL group. Additionally, the protein levels of VEGFA, FGF2 and MMP-9 were raised and those of GRP78, CHOP, PERK and ATF4 were lowered in the PA + BCL group of cells in a concentration-dependent manner.

CONCLUSION

BCL significantly attenuates PA-induced endothelial cell dysfunction by inhibiting endoplasmic reticulum stress.

Baicalin Exhibits a Protective Effect against Cisplatin-Induced Cytotoxic Damage in Canine Renal Tubular Epithelial Cells

Renal failure is a common chronic disease in dogs that substantially affects both their quality of life and longevity. The objective of this study was to assess the protective mechanisms of baicalin in cisplatin-induced Madin-Darby canine kidney (MDCK) epithelial cells' apoptosis model and explore the impacts of baicalin at varying doses on various indexes, such as cisplatin-induced MDCK cell apoptosis, oxidation and antioxidation, and inflammatory factors. (Methods) MDCK cells in the logarithmic growth phase were randomly divided into a control group, a model group (20 μmol/L cisplatin), and a baicalin-protection group (20 μmol/L cisplatin + 50, 25 μmol/L baicalin) and received the corresponding treatments for 24 h. The effects of cisplatin on MDCK cell apoptosis, oxidation and antioxidation, inflammatory factors, and other indicators were studied, and the relieving effect of baicalin on cisplatin-induced MDCK cell damage was explored. Calcein/PI staining and Annexin V-FITC/PI staining showed that cisplatin induced the apoptosis of MDCK cells, while baicalin effectively reduced the damage caused by cisplatin. The ELISA results demonstrated a significant elevation in the nitric oxide (NO) and malondialdehyde (MDA) levels within the MDCK cells following treatment with cisplatin (p < 0.01). In addition, superoxide dismutase (SOD), glutathione peroxidase (GSH), and catalase (CAT) activities remarkably declined (p < 0.01), while tumor necrosis factor α (TNF-α), interleukin-1β (IL-1β), and interleukin-6 (IL-6) expression within the MDCK cells were apparently elevated (p < 0.01). However, baicalin treatment resulted in opposite changes in these factors. The findings suggested that baicalin exhibits potential in mitigating cisplatin-induced oxidative stress and inflammation in MDCK cells. As revealed with the Western blot results, cisplatin promoted P62, P53, and BAX protein levels, increased mTOR phosphorylation, inhibited AMPK phosphorylation, and reduced Beclin1 and BCL-2 protein levels. However, a contrasting trend was observed following baicalin treatment. Cisplatin can inhibit the activity of MDCK cells, lead to abnormalities in oxidation and antioxidation functions and cell inflammatory factors, and accelerate cell apoptosis. Moreover, baicalin can significantly alleviate the damage of cisplatin to MDCK cells.