Tetramethylpyrazine promotes angiogenesis and nerve regeneration and nerve defect repair in rats with spinal cord injury

Bioactive compounds from Chinese herbal plants for neurological health: mechanisms, pathways, and functional food applications

Neurological disorders pose significant global public health challenges, with a rising prevalence and complex pathophysiological mechanisms that impose substantial social and economic burdens. Traditional Chinese Medicine (TCM), with its holistic approach and multi-target effects, has gained increasing attention in the treatment of neurological diseases. This review explores bioactive compounds derived from Chinese herbal plants, focusing on their mechanisms of action, underlying pathways, and potential applications in functional food development. The review highlights the neuroprotective properties of flavonoids, alkaloids, polysaccharides, and polyphenols found in key TCM herbs such as Scutellaria baicalensis, Salvia miltiorrhiza, Ligusticum chuanxiong, and Gastrodia elata. These compounds have demonstrated significant anti-inflammatory, antioxidant, and neurogenic effects, making them promising candidates for the prevention and treatment of neurological conditions, including Alzheimer's disease (AD), Parkinson's disease (PD), and depression. Furthermore, the synergistic effects of TCM formulations targeting multiple signaling pathways offer advantages over single-target therapies, especially in combating neurodegenerative diseases. The review also discusses the challenges and future directions for integrating these bioactive compounds into functional foods and dietary supplements, aiming to improve neurological health and enhance clinical outcomes. Ultimately, this work aims to provide valuable insights into the potential of TCM-based interventions for promoting neurological well-being and addressing the global burden of neurological disorders.

Progress of Exosomal MicroRNAs and Traditional Chinese Medicine Monomers in Neurodegenerative Diseases

Exosomes, extracellular vesicles secreted by various cells, actively participate in intercellular communication by facilitating the exchange of crucial molecular information such as DNA, RNA, and lipids. Within this intricate network, microRNAs, endogenous non-coding small RNAs, emerge as pivotal regulators of post-transcriptional gene expression, significantly influencing the development of neurodegenerative diseases. The historical prominence of traditional Chinese medicine (TCM) in clinical practice in China underscores its enduring significance. Notably, TCM monomers, serving as active constituents within herbal medicine, assume a critical role in the treatment of neurodegenerative diseases, particularly in mitigating oxidative stress, inhibiting apoptosis, and reducing inflammation. This comprehensive review aims to delineate the specific involvement of exosomal microRNAs in various neurodegenerative diseases, including Alzheimer's disease, Parkinson's disease, Huntington's disease, stroke, and amyotrophic lateral sclerosis. Furthermore, the exploration extends to the application of TCM monomers, elucidating their efficacy as therapeutic agents in these conditions. Additionally, the review examines the utilization of exosomes as drug delivery carriers in the context of neurodegenerative diseases, providing a nuanced understanding of the potential synergies between TCM and modern therapeutic approaches. This synthesis of knowledge aims to contribute to the advancement of our comprehension of the intricate molecular mechanisms underlying neurodegeneration and the potential therapeutic avenues offered by TCcom interventions.

Tetramethylpyrazine alleviates ferroptosis and promotes functional recovery in spinal cord injury by regulating GPX4/ACSL4

OBJECTIVE

Tetramethylpyrazine (TMP) has been demonstrated to alleviate neuronal ferroptosis following spinal cord injury (SCI), thereby promoting neural repair. However, the precise underlying mechanisms remain elusive.

METHODS

The SCI model was established using a modified version of Allen's method. TMP (40, 80, 120, and 160 mg/kg) and ras-selective lethal 3 (RSL3) (5 mg/kg) were administered intraperitoneally once daily for 7 days. HE and Nissl staining were employed to examine histomorphology and neurons, respectively. Perls staining was used to identify the distribution of iron. A transmission electron microscope was used to observe the microcosmic morphology of mitochondria. Immunofluorescence staining and Western blot were used to analyze neuronal nuclear protein (NeuN) and glial fibrillary acidic protein (GFAP) surrounding injury sites. Additionally, glutathione peroxidase 4 (GPX4)/NeuN + cells and acyl-CoA synthetase long-chain family member 4 (ACSL4)/NeuN + cells were observed. RT-qPCR was conducted to examine the mRNA expression levels of GPX4 and ACSL4. ELISA were used to quantify the concentrations of GPX4, reactive oxygen species (ROS), L-glutathione (GSH), malondialdehyde (MDA), superoxide dismutase (SOD), and tissue iron.

RESULTS

TMP had an inhibitory effect on the concentrations of tissue iron, ROS, GSH, MDA, and SOD. TMP improved the microcosmic morphology of mitochondria and increased GPX4 level while decreasing that of ACSL4. TMP reduced lesion sizes, enhanced neuronal survival, and inhibited glial scar formation. However, the effect of TMP can be effectively reversed by RSL3.

CONCLUSION

TMP alleviates neuronal ferroptosis by regulating the GPX4/ACSL4 axis, thereby protecting the remaining neurons surrounding injury sites and reducing glial scar formation.

Tetramethylpyrazine inhibits the inflammatory response by downregulating the TNFR1/IκB-α/NF-κB p65 pathway after spinal cord injury

Previous studies have demonstrated that tetramethylpyrazine (TMP) can enhance the recovery of motor function in spinal cord injury (SCI) rats. However, the underlying mechanism involved in this therapeutic effect remains to be elucidated. We conducted RNA sequencing with a network pharmacology strategy to predict the targets and mechanism of TMP for SCI. The modified Allen's weight-drop method was used to construct an SCI rat model. The results indicated that the nuclear transfer factor-κB (NF-κB) pathway was identified through the Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis, and an inflammatory response was identified through the Gene Ontology (GO) enrichment analysis. Tumor necrosis factor (TNF) was identified as a crucial target. Western blotting revealed that TMP decreased the protein expression of TNF superfamily receptor 1 (TNFR1), inhibitor κB-α (IκB-α), and NF-κB p65 in spinal cord tissues. Enzyme-linked immunosorbent assay (ELISA) and immunohistochemistry (IHC) demonstrated that TMP inhibited TNF-α, interleukin-1β (IL-1β), reactive oxygen species (ROS), and malondialdehyde (MDA) expression and enhanced superoxide dismutase (SOD) expression. Histopathological observation and behavior assessments showed that TMP improved morphology and motor function. In conclusion, TMP inhibits inflammatory response and oxidative stress, thereby exerting a neuroprotective effect that may be related to the regulation of the TNFR1/IκB-α/NF-κB p65 signaling pathway.