TANK-binding kinase 1 and Janus kinase 2 play important roles in the regulation of mitogen-activated protein kinase phosphatase-1 expression after toll-like receptor 4 activation

Progress in Research on TLR4-Mediated Inflammatory Response Mechanisms in Brain Injury after Subarachnoid Hemorrhage

Subarachnoid hemorrhage (SAH) is one of the common clinical neurological emergencies. Its incidence accounts for about 5-9% of cerebral stroke patients. Even surviving patients often suffer from severe adverse prognoses such as hemiplegia, aphasia, cognitive dysfunction and even death. Inflammatory response plays an important role during early nerve injury in SAH. Toll-like receptors (TLRs), pattern recognition receptors, are important components of the body's innate immune system, and they are usually activated by damage-associated molecular pattern molecules. Studies have shown that with TLR 4 as an essential member of the TLRs family, the inflammatory transduction pathway mediated by it plays a vital role in brain injury after SAH. After SAH occurrence, large amounts of blood enter the subarachnoid space. This can produce massive damage-associated molecular pattern molecules that bind to TLR4, which activates inflammatory response and causes early brain injury, thus resulting in serious adverse prognoses. In this paper, the process in research on TLR4-mediated inflammatory response mechanism in brain injury after SAH was reviewed to provide a new thought for clinical treatment.

Natural products of traditional Chinese medicine treat atherosclerosis by regulating inflammatory and oxidative stress pathways

Atherosclerosis (AS) is a prevalent arteriosclerotic vascular disease that forms a pathological basis for coronary heart disease, stroke, and other diseases. Inflammatory and oxidative stress responses occur throughout the development of AS. Treatment for AS over the past few decades has focused on administering high-intensity statins to reduce blood lipid levels, but these inevitably damage liver and kidney function over the long term. Natural medicines are widely used to prevent and treat AS in China because of their wide range of beneficial effects, low toxicity, and minimal side effects. We searched for relevant literature over the past 5 years in databases such as PubMed using the keywords, “atherosclerosis,” “traditional Chinese medicine,” “natural medicines,” “inflammation,” and “oxidative stress.” We found that the PI3K/AKT, TLR4, JAK/STAT, Nrf2, MAPK, and NF-κB are the most relevant inflammatory and oxidative stress pathways in AS. This review summarizes studies of the natural alkaloid, flavonoid, polyphenol, saponin, and quinone pathways through which natural medicines used to treat AS. This study aimed to update and summarize progress in understanding how natural medicines treat AS via inflammatory and oxidative stress-related signaling pathways. We also planned to create an information base for the development of novel drugs for future AS treatment.

STAT3 Differentially Regulates TLR4-Mediated Inflammatory Responses in Early or Late Phases

Toll-like receptor 4 (TLR4) signaling is an important therapeutic target to manage lipopolysaccharide (LPS)-induced inflammation. The transcription factor signal transducer and activator of transcription 3 (STAT3) has been identified as an important regulator of various immune-related diseases and has generated interest as a therapeutic target. Here, we investigated the time-dependent roles of STAT3 in LPS-stimulated RAW264.7 macrophages. STAT3 inhibition induced expression of the pro-inflammatory genes iNOS and COX-2 at early time points. STAT3 depletion resulted in regulation of nuclear translocation of nuclear factor (NF)-κB subunits p50 and p65 and IκBα/Akt/PI3K signaling. Moreover, we found that one Src family kinase, Lyn kinase, was phosphorylated in STAT3 knockout macrophages. In addition to using pharmacological inhibition of NF-κB, we found out that STAT3KO activation of NF-κB subunit p50 and p65 and expression of iNOS was significantly inhibited; furthermore, Akt tyrosine kinase inhibitors also inhibited iNOS and COX-2 gene expression during early time points of LPS stimulation, demonstrating an NF-κB- Akt-dependent mechanism. On the other hand, iNOS expression was downregulated after prolonged treatment with LPS. Activation of NF-κB signaling was also suppressed, and consequently, nitric oxide (NO) production and cell invasion were repressed. Overall, our data indicate that STAT3 differentially regulates early- and late-phase TLR4-mediated inflammatory responses.

Dietary inclusion of plant ingredients induces epigenetic changes in the intestine of zebrafish

Epigenetic modifications, such as DNA methylation, can be regulated by nutrition and dietary factors. There has been a large increase in the use of sustainable plant-based protein sources in fish feed due to limitations of fishmeal resources, which are needed to sustain a rapidly growing aquaculture industry. With this major transition from marine ingredients to plant-based diets, fish are abruptly introduced to changes in dietary composition and exposed to a variety of phytochemicals, some of which known to cause epigenetic changes in mammals. However, the effect of plant ingredients on the epigenome of fish is barely understood. In the present study, the nutriepigenomic effects of the addition of pea, soy, and wheat gluten protein concentrate to aquafeeds were investigated using zebrafish as a model. A genome-wide analysis of DNA methylation patterns was performed by reduced representation bisulphite sequencing to examine global epigenetic alterations in the mid intestine after a 42-day feeding trial. We found that inclusion of 30% of wheat gluten, pea and soy protein concentrate in the diet induced epigenetic changes in the mid intestine of zebrafish. A large number of genes and intergenic regions were differentially methylated with plant-based diets. The genes concerned were related to immunity, NF-κB system, ubiquitin-proteasome pathway, MAPK pathway, and the antioxidant defence system. Epigenetic regulation of several biological processes, including neurogenesis, cell adhesion, response to stress and immunity was also observed. Ultimately, the observed epigenetic changes may enable zebrafish to rapidly regulate inflammation and maintain intestinal homoeostasis when fed plant protein-based diets.