The potential role of glucose metabolism, lipid metabolism, and amino acid metabolism in the treatment of Parkinson's disease

Roles of Lysine Methylation in Glucose and Lipid Metabolism: Functions, Regulatory Mechanisms, and Therapeutic Implications

Glucose and lipid metabolism are essential energy sources for the body. Dysregulation in these metabolic pathways is a significant risk factor for numerous acute and chronic diseases, including type 2 diabetes (T2DM), Alzheimer's disease (AD), obesity, and cancer. Post-translational modifications (PTMs), which regulate protein structure, localization, function, and activity, play a crucial role in managing cellular glucose and lipid metabolism. Among these PTMs, lysine methylation stands out as a key dynamic modification vital for the epigenetic regulation of gene transcription. Emerging evidence indicates that lysine methylation significantly impacts glucose and lipid metabolism by modifying key enzymes and proteins. This review summarizes the current understanding of lysine methylation's role and regulatory mechanisms in glucose and lipid metabolism. We highlight the involvement of methyltransferases (KMTs) and demethylases (KDMs) in generating abnormal methylation signals affecting these metabolic pathways. Additionally, we discuss the chemical biology and pharmacology of KMT and KDM inhibitors and targeted protein degraders, emphasizing their clinical implications for diseases such as diabetes, obesity, neurodegenerative disorders, and cancers. This review suggests that targeting lysine methylation in glucose and lipid metabolism could be an ideal therapeutic strategy for treating these diseases.

The Effects of Ketogenic Diet on Brain Gene Expressions in Type 2 Diabetes Background

Type 2 diabetes mellitus (T2DM) is a major risk factor of a number of neurodegenerative diseases (NDDs). Ketogenic diet (KD) has significant beneficial effects on glycemic control and may act effectively against NDDs, but the mechanism remains unclear. In this study, we aimed to investigate the potential effects of KD on gene expressions in the brains of T2DM model mice. Male db/db mice at the age of 9 weeks were fed with KD or normal diet to the age of 6 months, and the whole brains were subjected to mRNA-seq analysis for differentially expressed genes. KD significantly lowered fasting glucose and body weights in db/db mice (P < 0.05), and the expression of 189 genes in the brain were significantly changed (P < 0.05, |log2| > 1). Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses revealed that the differentially expressed genes upon KD are involved in inflammatory responses and the functions of biosynthesis. In inflammatory responses, NF-κB signaling pathway, viral protein interaction with cytokine and cytokine receptor, and cytokine-cytokine receptor interaction pathways were enriched, and in biosynthesis pathways, genes functioning in lipid and amino acid metabolism, protein synthesis, and energy metabolism were enriched. Moreover, consistent with the gene set enrichment analysis results, proteasomal activity measured biochemically were enhanced in KD-fed T2DM mice. These data may facilitate the understanding of how KD can be protective to the brain in T2DM background. KD could be a new strategy for the prevention of NDDs in T2DM patients.

Nutrition in chronic inflammatory conditions: Bypassing the mucosal block for micronutrients

Nutritional Immunity is one of the most ancient innate immune responses, during which the body can restrict nutrients availability to pathogens and restricts their uptake by the gut mucosa (mucosal block). Though this can be a beneficial strategy during infection, it also is associated with non-communicable diseases-where the pathogen is missing; leading to increased morbidity and mortality as micronutritional uptake and distribution in the body is hindered. Here, we discuss the acute immune response in respect to nutrients, the opposing nutritional demands of regulatory and inflammatory cells and particularly focus on some nutrients linked with inflammation such as iron, vitamins A, Bs, C, and other antioxidants. We propose that while the absorption of certain micronutrients is hindered during inflammation, the dietary lymph path remains available. As such, several clinical trials investigated the role of the lymphatic system during protein absorption, following a ketogenic diet and an increased intake of antioxidants, vitamins, and minerals, in reducing inflammation and ameliorating disease.

Association of accelerometer-measured physical activity intensity, sedentary time, and exercise time with incident Parkinson's disease

Evidence regarding the association between physical activity and Parkinson's disease (PD) risk is generally limited due to the use of self-report questionnaires. We aimed to quantify the separate and combined effects of accelerometer-measured light physical activity (LPA), moderate-to-vigorous physical activity (MVPA), sedentary time and exercise timing with incident PD. 96,422 participants without prior PD and with usable accelerometer data were included from UK Biobank. Time spent in sedentary activity, LPA, MVPA, and exercise timing were estimated using machine learning models. The study outcome was incident PD. Over a median follow-up duration of 6.8 years, 313 participants developed PD. There was a L-shaped association for LPA and MVPA, and a reversed L-shaped association for sedentary time, with the risk of incident PD (all P for nonlinearity < 0.001). Similar trends were found across three time-windows (morning, midday-afternoon, and evening). Compared with those with both low LPA (<3.89 h/day) and low MVPA (<0.27 h/day), the adjusted HR (95% CI) of PD risk was 0.49 (0.36-0.66), 0.19 (0.36-0.66) and 0.13 (0.09-0.18), respectively, for participants with high MVPA only, high LPA only, and both high LPA and high MVPA. Moreover, participants with both low LPA and high sedentary time (≥9.41 h/day) (adjusted HR, 5.59; 95% CI: 4.10-7.61), and those with both low MVPA and high sedentary time (adjusted HR, 3.93; 95% CI: 2.82-5.49) had the highest risk of incident PD. In conclusion, regardless of exercise timing (morning, midday-afternoon, and evening), there was an inverse association for accelerometer-measured MVPA and LPA, and a positive association for sedentary time, with incident PD.