RESUMO
This review article covers the therapeutic potential of the plants Harpagophytum procumbens and Turnera subulata in the treatment of neurodegenerative diseases. Despite the recognition of their beneficial properties, there is notable shortage of specific clinical and in vitro studies on these species regarding neurodegenerative diseases. Compounds such as harpagosides and vite-xin-2-O-rhamnoside, found in Harpagophytum procumbens and Turnera subulata, respectively, as well as other antioxidants and anti-inflammatory agents, are associated with mechanisms of action that involve reducing oxidative stress and modulating the inflammatory response, indicating their therapeutic potential in these pathologies. Additionally, the use of nutraceuticals derived from medicinal plants has emerged as a promising approach, offering natural therapeutic alternatives. However, the pressing need for studies focusing on the pharmacokinetics, safety, and pharmacological interactions of these extracts for the treatment of neurodegenerative diseases is emphasized. This review also evaluated advances in nutraceutical delivery systems, highlighting technological innovations that can optimize the precise delivery of these compounds to patients. Such findings highlight the gaps in the study of these plants for the treatment of neurodegenerative diseases and, at the same time, the potential for opening new perspectives in the treatment of neurodegenerative diseases, providing expectations for innovative solutions in this critical domain of medicine.
RESUMO
OBJECTIVE: The aim of this study was to investigate the influence of smoking on the methylation and hydroxymethylation status of global DNA and specific sites of KRT14, KRT19, miR-9-3 and miR-137 genes in the healthy oral mucosa. METHODS: Samples of oral epithelial cells were collected using mouthwash from a population of former and current smokers and those who had never smoked. Genomic DNA was extracted, and global DNA methylation and hydroxymethylation was performed using an ELISA-based technique; DNA methylation at specific sites was performed using Methylation-Specific PCR (MSP) (KRT14, miR-9-3 and miR-137) or Methylation-Sensitive Restriction Enzymes (MSRE) (KRT19). K14 and K19 protein expression was analysed by immunohistochemistry. RESULTS: Higher levels of global DNA methylation were found in current smokers with over 15 years of consumption (p=0.04), but no differences were found in relation to global DNA hydroxymethylation. No differences in global DNA methylation and hydroxymethylation levels were found in relation to age or gender. Global DNA methylation was higher than the hydroxymethylation level (p<0.001) but they were not correlated in the oral mucosa. For specific sites, miR-9-3 hypomethylation was detected in current smokers (p<0.001). Additional analysis showed no difference in the methylation status when age, gender, period of consumption or amount of cigarettes were considered for any of the studied genes. K19 expression was higher in current smokers in comparison to former smokers and those who had never smoked (p<0.05). CONCLUSION: We concluded that smoking habits were capable of inducing changes in global DNA methylation, miR-9-3 methylation status and K19 expression.