Traumatic brain injury (TBI), known as mechanical damage to the brain, impairs the normal function of the brain seriously. Its clinical symptoms manifest as behavioral impairment, cognitive decline, communication difficulties, etc. The pathophysiological mechanisms of TBI are complex and involve inflammatory response, oxidative stress, mitochondrial dysfunction, blood‐brain barrier (BBB) disruption, and so on. Among them, oxidative stress, one of the important mechanisms, occurs at the beginning and accompanies the whole process of TBI. Most importantly, excessive oxidative stress causes BBB disruption and brings injury to lipids, proteins, and DNA, leading to the generation of lipid peroxidation, damage of nuclear and mitochondrial DNA, neuronal apoptosis, and neuroinflammatory response. Transcription factor NF‐E2 related factor 2 (Nrf2), a basic leucine zipper protein, plays an important role in the regulation of antioxidant proteins, such as oxygenase‐1(HO‐1), NAD(P)H Quinone Dehydrogenase 1 (NQO1), and glutathione peroxidase (GPx), to protect against oxidative stress, neuroinflammation, and neuronal apoptosis. Recently, emerging evidence indicated the knockout (KO) of Nrf2 aggravates the pathology of TBI, while the treatment of Nrf2 activators inhibits neuronal apoptosis and neuroinflammatory responses via reducing oxidative damage. Phytochemicals from fruits, vegetables, grains, and other medical herbs have been demonstrated to activate the Nrf2 signaling pathway and exert neuroprotective effects in TBI. In this review, we emphasized the contributive role of oxidative stress in the pathology of TBI and the protective mechanism of the Nrf2‐mediated oxidative stress response for the treatment of TBI. In addition, we summarized the research advances of phytochemicals, including polyphenols, terpenoids, natural pigments, and otherwise, in the activation of Nrf2 signaling and their potential therapies for TBI. Although there is still limited clinical application evidence for these natural Nrf2 activators, we believe that the combinational use of phytochemicals such as Nrf2 activators with gene and stem cell therapy will be a promising therapeutic strategy for TBI in the future.

Parkinson’s disease (PD) is a complex neurological disorder characterized by motor and nonmotor features. Although some drugs have been developed for the therapy of PD in a clinical setting, they only alleviate the clinical symptoms and have yet to show a cure. In this study, by employing the C. elegans model of PD, we found that ferulic acid (FA) significantly inhibited α‐synuclein accumulation and improved dyskinesia in NL5901 worms. Meanwhile, FA remarkably decreased the degeneration of dopaminergic (DA) neurons, improved the food‐sensing behavior, and reduced the level of reactive oxygen species (ROS) in 6‐OHDA‐induced BZ555 worms. The mechanistic study discovered that FA could activate autophagy in C. elegans, while the knockdown of 3 key autophagy‐related genes significantly revoked the neuroprotective effects of FA in α‐synuclein‐ and 6‐OHDA‐induced C. elegans models of PD, demonstrating that FA exerts an anti‐PD effect via autophagy induction in C. elegans. Furthermore, we found that FA could reduce 6‐OHDA‐ or H₂O₂‐induced cell death and apoptosis in PC‐12 cells. Moreover, FA was able to induce autophagy in stable GFP‐RFP‐LC3 U87 cells and PC‐12 cells, while bafilomycin A1 (Baf, an autophagy inhibitor) partly eliminated the protective effects of FA against 6‐OHDA‐ and H₂O₂‐induced cell death and ROS production in PC‐12 cells, further confirming that FA exerts an anti‐PD effect via autophagy induction in vitro. Collectively, our study provides novel insights for FA as a potent autophagy enhancer to effectively prevent neurodegenerative diseases such as PD in the future.

Blood retinal barrier (BRB) damage is an important pathogenesis of diabetic retinopathy, and alleviating BRB damage has become a key target for DR treatment. We previously found that Lycopene seed polyphenols (LSP) maintained BRB integrity by inhibiting NLRP3 inflammasome-mediated inflammation. However, it is still unknown whether LSP inhibits retinal neovascularization with abnormal capillaries and its mechanism of action. Here, we employed db/db mice and hRECs to find that LSP increases the level of glycolipid metabolism, maintains the morphology of retinal endothelial cells and inhibits acellular capillary neogenesis. Mechanistic studies revealed that LSP inhibits the NLRP3 inflammasome, reduces cell apoptosis in retinal tissue, increases tight junction protein (TJ) expression, and reduces vascular endothelial growth factor (VEGF) and Ve-Cadherin in vivo and in vitro. Collectively, this study finds that LSP inhibits inflammation and angiogenesis to improve BRB function to ameliorate DR.

Alzheimer's disease (AD) pathology involves amyloid-beta (Aβ) accumulation and neuronal toxicity, highlighting the need for therapeutic strategies that can both inhibit Aβ aggregation and promote pathogenic protein clearance. In this study, we identified Gaultheria leucocarpa as a medicinal plant with promising neuroprotective potential. Thioflavin T (ThT) fluorescence screening revealed that extracts from G. leucocarpa (GE), particularly the petroleum ether fraction of G. leucocarpa extract (GPF), effectively inhibited Aβ fibril formation in vitro. In cell-based assays, GPF significantly improved the viability of PC-12 ​cells exposed to Aβ peptides and fibrils, indicating protection against Aβ-induced cytotoxicity. Furthermore, GPF enhanced mitophagic activity, as demonstrated by increased GFP-LC3 puncta, elevated LC3-II/I ratio, and colocalization of GFP-LC3 with MitoTracker Red. Mechanistic investigations showed that GPF activates mitophagy via the AMPK/ULK1 pathway and inhibits the PI3K/AKT/mTOR pathway, resulting in enhanced degradation of APP and Tau proteins. In Caenorhabditis elegans models relevant to AD, GPF administration led to reduced Aβ deposits, delayed paralysis onset, improved food perception, and decreased oxidative stress. Collectively, these findings demonstrate that GPF exerts dual actions by inhibiting Aβ fibrillization and promoting mitophagy-mediated degradation of pathogenic proteins. The active ingredients identified from GPF extracts represent promising leads for the development of novel neuroprotective agents targeting AD-related pathological mechanisms.