ABSTRACT
Agmatine (AGM), a naturally occurring polyamine derived from L-arginine, has shown significant potential for neuroprotection in Parkinson's Disease (PD) due to its multifaceted biological activities, including antioxidant, anti-inflammatory, and anti-apoptotic effects. This review explores the therapeutic potential of AGM in treating PD, focusing on its neuroprotective mechanisms and evidence from preclinical studies. AGM has been demonstrated to mitigate the neurotoxic effects of rotenone (ROT) by improving motor function, reducing oxidative stress markers, and decreasing levels of pro-inflammatory cytokines in animal models. Additionally, AGM protects against the loss of TH + neurons, crucial for dopamine synthesis. The neuroprotective properties of AGM are attributed to its ability to modulate several key pathways implicated in PD pathogenesis, such as inhibition of NMDA receptors, activation of Nrf2, and suppression of the HMGB1/ RAGE/ TLR4/ MyD88/ NF-κB signaling cascade. Furthermore, the potential of agmatine to promote neurorestoration is highlighted by its role in enhancing neuroplasticity elements such as CREB, BDNF, and ERK1/2. This review highlights agmatine's promising therapeutic potential in PD management, suggesting that it could offer both symptomatic relief and neuroprotective benefits, thereby modifying the disease course and improving the quality of life for patients. Further research is warranted to translate these preclinical findings into clinical applications.
ABSTRACT
Head and neck cancer (HNC) refers to the epithelial malignancies of the upper aerodigestive tract. HNCs have a constant yet slow-growing rate with an unsatisfactory overall survival rate globally. The development of new blood vessels from existing blood conduits is regarded as angiogenesis, which is implicated in the growth, progression, and metastasis of cancer. Aberrant angiogenesis is a known contributor to human cancer progression. Representing a promising therapeutic target, the blockade of angiogenesis aids in the reduction of the tumor cells oxygen and nutrient supplies. Despite the promise, the association of existing anti-angiogenic approaches with severe side effects, elevated cancer regrowth rates, and limited survival advantages is incontrovertible. Exosomes appear to have an essential contribution to the support of vascular proliferation, the regulation of tumor growth, tumor invasion, and metastasis, as they are a key mediator of information transfer between cells. In the exocrine region, various types of noncoding RNAs (ncRNAs) identified to be enriched and stable and contribute to the occurrence and progression of cancer. Mounting evidence suggest that exosome-derived ncRNAs are implicated in tumor angiogenesis. In this review, the characteristics of angiogenesis, particularly in HNC, and the impact of ncRNAs on HNC angiogenesis will be outlined. Besides, we aim to provide an insight on the regulatory role of exosomes and exosome-derived ncRNAs in angiogenesis in different types of HNC.