Baicalin Protects against Thrombin-Induced Cell Injury in Human Umbilical Vein Endothelial Cells

Baicalin and Baicalein Enhance Cytotoxicity, Proapoptotic Activity, and Genotoxicity of Doxorubicin and Docetaxel in MCF-7 Breast Cancer Cells

Breast cancer is a major health concern and the leading cause of death among women worldwide. Standard treatment often involves surgery, radiotherapy, and chemotherapy, but these come with side effects and limitations. Researchers are exploring natural compounds like baicalin and baicalein, derived from the Scutellaria baicalensis plant, as potential complementary therapies. This study investigated the effects of baicalin and baicalein on the cytotoxic, proapoptotic, and genotoxic activity of doxorubicin and docetaxel, commonly used chemotherapeutic drugs for breast cancer. The analysis included breast cancer cells (MCF-7) and human endothelial cells (HUVEC-ST), to assess potential effects on healthy tissues. We have found that baicalin and baicalein demonstrated cytotoxicity towards both cell lines, with more potent effects observed in baicalein. Both flavonoids, baicalin (167 µmol/L) and baicalein (95 µmol/L), synergistically enhanced the cytotoxic, proapoptotic, and genotoxic activity of doxorubicin and docetaxel in breast cancer cells. In comparison, their effects on endothelial cells were mixed and depended on concentration and time. The results suggest that baicalin and baicalein might be promising complementary agents to improve the efficacy of doxorubicin and docetaxel anticancer activity. However, further research is needed to validate their safety and efficacy in clinical trials.

The Pharmacological Effects of Silver Nanoparticles Functionalized with Eptifibatide on Platelets and Endothelial Cells

Purpose

In the search for new drug delivery platforms for cardiovascular diseases and coating of medical devices, we synthesized eptifibatide-functionalized silver nanoparticles (AgNPs-EPI) and examined the pharmacological activity of AgNPs-EPI on platelets and endothelial cells in vitro and ex vivo.

Methods

Spherical AgNPs linked to eptifibatide were synthesized and characterized. Cytotoxicity was measured in microvascular endothelial cells (HMEC-1), platelets and red blood cells. Platelet mitochondrial respiration was measured using the Oxygraph-2k, a high-resolution modular respirometry system. The effect of AgNPs-EPI on the aggregation of washed platelets was measured by light aggregometry and the ex vivo occlusion time was determined using a reference laboratory method. The surface amount of platelet receptors such as P-selectin and GPIIb/IIIa was measured. The influence of AgNPS-EPI on blood coagulation science was assessed. Finally, the effect of AgNPs-EPI on endothelial cells was measured by the levels of 6-keto-PGF1alpha, tPa, cGMP and vWF.

Results

We describe the synthesis of AgNPs using eptifibatide as the stabilizing ligand. The molecules of this drug are directly bonded to the surface of the nanoparticles. The synthesized AgNPs-EPI did not affect the viability of platelets, endothelial cells and erythrocytes. Preincubation of platelets with AgNPs-EPI protected by mitochondrial oxidative phosphorylation capacity. AgNPs-EPI inhibited aggregation-induced P-selectin expression and GPIIb/IIIa conformational changes in platelets. AgNPs-EPI caused prolongation of the occlusion time in the presence of collagen/ADP and collagen/adrenaline. AgNPs-EPI regulated levels of 6-keto-PGF1alpha, tPa, vWf and cGMP produced in thrombin stimulated HMEC-1 cells.

Conclusion

AgNPs-EPI show anti-aggregatory activity at concentrations lower than those required by the free drug acting via regulation of platelet aggregation, blood coagulation, and endothelial cell activity. Our results provide proof-of-principle evidence that AgNPs may be used as an effective delivery platform for antiplatelet drugs.

Baicalin Alleviates Thrombin-Induced Inflammation in Vascular Smooth Muscle Cells

Atherosclerosis (AS) is a chronic inflammatory disease of the arterial intima. As AS represents the most common type of vascular disease, it affects millions of individuals and is a source of high morbidity and mortality rates worldwide. Overwhelming evidence indicates that AS-related inflammation is mediated by proinflammatory cytokines, chemokines, adhesion molecules and inflammatory signaling pathways, with each of these factors being shown to play critical roles during the entire progression of AS. While a number of drugs have been approved for use in the treatment of AS, their benefits are modest, which underscores the urgency for the development of new drug therapies. In part, these deficits in effective drugs can be attributable to the lack of a clear understanding of the molecular mechanisms of AS. In this study, we investigate the capacity for thrombin to trigger inflammation and induce cell proliferation in vascular smooth muscle cells (VSMCs). We then assessed the effects of baicalin and its potential mechanisms on VSMC inflammation as induced by thrombin. Baicalin, which is a natural bioactive compound of S. baicalensis Georgi (SBG), exerted a protective effect against thrombin-induced VSMC inflammation as resulting from the upregulation of PAR-1. This protection as exerted by baicalin appears to reside in its capacity to produce an inhibitory effect on the thrombin-induced activation of the ERK1/2 pathway. These findings suggest that baicalin may be a promising candidate for the treatment of atherosclerosis.

Baicalin Inhibits Cell Proliferation and Inflammatory Cytokines Induced by Tumor Necrosis Factor α (TNF-α) in Human Immortalized Keratinocytes (HaCaT) Human Keratinocytes by Inhibiting the STAT3/Nuclear Factor kappa B (NF-κB) Signaling Pathway

Background

Baicalin is a flavone isolated from the root of Scutellaria baicalensis and is used in traditional Chinese medicine. Psoriasis is a persistent and recurrent chronic inflammatory skin disease that is characterized by inflammation and increased proliferation of keratinocytes. This study aimed to investigate the effects of baicalin on HaCaT immortalized human keratinocytes in vitro and the molecular mechanisms involved.

Material/Methods

HaCaT keratinocytes were cultured in increasing concentrations of baicalin at 6.25 μM, 12.5 μM, and 25 μM. The in vitro model of psoriasis was established using HaCaT cells treated with tumor necrosis factor-α (TNF-α). The MTT assay was used to asses cell viability and apoptosis. Western blot was used to measure the expression of Bcl-2, Bax, pro-caspase-3, and cleaved caspase-3, and enzyme-linked immunosorbent assay (ELISA) was performed to detect inflammatory cytokines. Quantitative reverse transcription-polymerase chain reaction (qRT-PCR) was used to detect the levels of STAT3 and p65 mRNA.

Results

Baicalin reduced cell viability and induced apoptosis of HaCaT human keratinocytes in a dose-dependent manner. Increased cell viability and the expression of inflammatory cytokines by HaCaT cells induced by TNF-α were significantly inhibited by baicalin. Baicalin significantly inhibited the activation of the STAT3/NF-κB pathway in HaCaT cells stimulated by TNF-α.

Conclusions

Baicalin inhibited the proliferation and expression of inflammatory cytokines in HaCaT immortalized human keratinocytes in vitro through the inhibition of the STAT3/NF-κB signaling pathway.