Linking the low-density lipoprotein receptor-binding segment enables the therapeutic 5-YHEDA peptide to cross the blood-brain barrier and scavenge excess iron and radicals in the brain of senescent mice

The J bs-5YP peptide can alleviate dementia in senile mice by restoring the transcription of Slc40a1 to secrete the excessive iron from brain

INTRODUCTION

With age and ATP decrease in the body, the transcription factors hypophosphorylation weakens the transcription of Slc40a1 and hinders the expression of the iron discharger ferroportin. This may lead to iron accumulation in the brain and the catalysis of free radicals that damage cerebral neurons and eventually lead to Alzheimer's disease (AD).

OBJECTIVES

To prevent AD caused by brain iron excretion disorders and reveal the mechanism of J bs-5YP peptide restoring ferroportin.

METHODS

We prepared J bs-YP peptide and administered it to the senile mice with dementia. Then, the intelligence of the mice was tested using a Morris Water Maze. The ATP content in the body was detected using the ATP hydrophysis and Phosphate precipitation method. The activation of Slc40a1 transcription was assayed with ATAC seq and the ferroportin, as well as the phosphorylation levels of Ets1 in brain were detected by Western Blot.

RESULTS

The phosphorylation level of Ets1in brain was enhanced, and subsequently, the transcription of Slc40a1 was activated and ferroportin was increased in the brain, the levels of iron and free radicals were reduced, with the neurons protection, and the dementia was ultimately alleviated in the senile mice.

CONCLUSION

J bs-5YP can recover the expression of ferroportin to excrete excessive iron in the brain of senile mice with dementia by enhancing the transcription of Slc40a1 via phosphorylating Ets1, revealing the potential of J bs-5YP as a drug to alleviate senile dementia.

Adipocyte metabolic state regulates glial phagocytic function

Obesity and type 2 diabetes are well-established risk factors for neurodegenerative disorders1-4, yet the underlying mechanisms remain poorly understood. The adipocyte-brain axis is crucial for brain function, as adipocytes secrete signaling molecules, including lipids and adipokines, that impinge on neural circuits to regulate feeding and energy expenditure5. Disruptions in the adipocyte-brain axis are associated with neurodegenerative conditions6, but the causal links are not fully understood. Neural debris accumulates with age and injury, and glial phagocytic function is crucial for clearing this debris and maintaining a healthy brain microenvironment7-9. Using adult Drosophila, we investigate how adipocyte metabolism influences glial phagocytic activity in the brain. We demonstrate that a prolonged obesogenic diet increases adipocyte fatty acid oxidation and ketogenesis. Genetic manipulations that mimic obesogenic diet-induced changes in adipocyte lipid and mitochondrial metabolism unexpectedly reduce the expression of the phagocytic receptor Draper in Drosophila microglia-like cells in the brain. We identify Apolpp-the Drosophila equivalent of human apolipoprotein B (ApoB)-as a critical adipocyte-derived signal that regulates glial phagocytosis. Additionally, we show that Lipoprotein Receptor 1 (LpR1), the LDL receptor on phagocytic glia, is required for glial capacity to clear injury-induced neuronal debris. Our findings establish that adipocyte-brain lipoprotein signaling regulates glial phagocytic function, revealing a novel pathway that links adipocyte metabolic disorders with neurodegeneration.

Research progress of ferroptosis in Alzheimer disease: A review

Ferroptosis is an emerging form of programmed cell death triggered by iron-dependent lipid peroxidation and reactive oxygen species (ROS). Alzheimer disease (AD), a neurodegenerative disorder, is characterized by the degeneration of nerve cells. Recent research has indicated a significant association between ferroptosis and AD; however, the precise underlying mechanism remains elusive. It is postulated that ferroptosis may impact the accumulation of iron ions within the body by influencing iron metabolism, amino acid metabolism, and lipid metabolism, ultimately leading to the induction of ferroptosis in nerve cells. This article centers on the attributes and regulatory mechanism of ferroptosis, the correlation between ferroptosis and AD, and the recent advancements in the therapeutic approach of targeting ferroptosis for the treatment of AD. These results suggest that ferroptosis could potentially serve as a pivotal focus in future research on AD.

Polymeric Metal Contrast Agents for T1-Weighted Magnetic Resonance Imaging of the Brain

Imaging plays an integral role in diagnostics and treatment monitoring for conditions affecting the brain; enhanced brain imaging capabilities will improve upon both while increasing the general understanding of how the brain works. T₁-weighted magnetic resonance imaging is the preferred modality for brain imaging. Commercially available contrast agents, which are often required to render readable brain images, have considerable toxicity concerns. In recent years, much progress has been made in developing new contrast agents based on the magnetic features of gadolinium, iron, or magnesium. Nanotechnological approaches for these systems allow for the protected integration of potentially harmful metals with added benefits like reduced dosage and improved transport. Polymeric enhancement of each design further improves biocompatibility while allowing for specific brain targeting. This review outlines research on polymeric nanomedicine designs for T₁-weighted contrast agents that have been evaluated for performance in the brain.

Production of Bioactive Peptides from Sea Cucumber and Its Potential Health Benefits: A Comprehensive Review

Bioactive peptides from food have been widely studied due to their potential applications as functional foods and pharmaceuticals. Sea cucumber, a traditional tonic food, is characterized by high protein and low fat, thereby substrates are being studied to release sea cucumber peptides (SCPs). Although recent studies have shown that SCPs have various bioactive functions, there is no literature reviewing the development status of SCPs. In this review, we summarized the production of SCPs, including their purification and identification, then mainly focused on the comprehensive potential health benefits of SCP in vivo and in vitro, and finally discussed the challenge facing the development of SCPs. We found that SCPs have well-documented health benefits due to their antioxidation, anti-diabetes, ACE inhibitory, immunomodulatory, anti-cancer, anti-fatigue, anti-aging, neuroprotection, micromineral-chelating, etc. However, the structure-activity relationships of SCPs and the functional molecular mechanisms underlying their regulation in vivo need further investigation. Research on the safety of SCP and its potential regulation mechanism will contribute to transferring these findings into commercial applications. Hopefully, this review could promote the development and application of SCPs in further investigation and commercialization.

Exogenous Bioactive Peptides Have a Potential Therapeutic Role in Delaying Aging in Rodent Models

In recent years, some exogenous bioactive peptides have been shown to have promising anti-aging effects. These exogenous peptides may have a mechanism similar to endogenous peptides, and some can even regulate the release of endogenous active peptides and play a synergistic role with endogenous active peptides. Most aging studies use rodents that are easy to maintain in the laboratory and have relatively homogenous genotypes. Moreover, many of the anti-aging studies using bioactive peptides in rodent models only focus on the activity of single endogenous or exogenous active peptides, while the regulatory effects of exogenous active peptides on endogenous active peptides remain largely under-investigated. Furthermore, the anti-aging activity studies only focus on the effects of these bioactive peptides in individual organs or systems. However, the pathological changes of one organ can usually lead to multi-organ complications. Some anti-aging bioactive peptides could be used for rescuing the multi-organ damage associated with aging. In this paper, we review recent reports on the anti-aging effects of bioactive peptides in rodents and summarize the mechanism of action for these peptides, as well as discuss the regulation of exogenous active peptides on endogenous active peptides.

Exercise-Mediated Alteration of miR-192-5p Is Associated with Cognitive Improvement in Alzheimer's Disease

INTRODUCTION

Physical exercise is an important component of managing Alzheimer's disease (AD). miRNAs can be modulated by exercise intervention.

OBJECTIVE

The study explored the involvement and potential mechanism of miR-192-5p in the protective effect of physical exercise on AD.

METHODS

Ninety AD patients were enrolled, in which 45 cases accepted cycling training for continuous 3 months. The expression changes of miR-192-5p before and after exercise were analyzed by reverse transcription-quantitative PCR. 8-month-old APP/PS1 double Tg mice were used as the AD animal model. Mice in the voluntary exercise (VE) group received VE for 4 weeks. Morris water maze (MWM) test was used to evaluate the learning and memory function. Enzyme-linked immunosorbent assay was used to calculate the level of IL-1β, IL-6, and TNF-α.

RESULTS

AD patients showed elevated MMSE scores, decreased ADAS-cog and NPI-Q scores after 3 months of exercise. miR-192-5p was downregulated in the serum of AD patients and correlated with the levels of MMSE score, ADAS-cog, and NPI-Q score. A positive association was detected between serum miR-192-5p with TNF-α, IL-6, and IL-1β levels. MiR-192-5p is downregulated in the hippocampus tissues of mice after VE. Overexpression of miR-192-5p reversed the neuroprotective effect of exercise on AD in mice and promoted the inflammatory response of AD mice.

CONCLUSION

MiR-192-5p can be modulated by the exercise intervention and involved in the protective effect of exercise on AD.

Epigenetics in Alzheimer's Disease

Alzheimer's disease (AD) is a neurodegenerative disease with unknown pathogenesis and complex pathological manifestations. At present, a large number of studies on targeted drugs for the typical pathological phenomenon of AD (Aβ) have ended in failure. Although there are some drugs on the market that indirectly act on AD, their efficacy is very low and the side effects are substantial, so there is an urgent need to develop a new strategy for the treatment of AD. An increasing number of studies have confirmed epigenetic changes in AD. Although it is not clear whether these epigenetic changes are the cause or result of AD, they provide a new avenue of treatment for medical researchers worldwide. This article summarizes various epigenetic changes in AD, including DNA methylation, histone modification and miRNA, and concludes that epigenetics has great potential as a new target for the treatment of AD.

Comprehensive Analysis of Mouse Hippocampal Lysine Acetylome Mediated by Sea Cucumber Peptides Preventing Memory Impairment

Memory impairment is becoming a potential health issue with the delicacy of diet and social stress. Sea cucumber peptides (SCP) prevent memory impairment, as previously reported. In this study, further research was performed using hippocampal lysine-acetylome to explore molecular regulation mechanisms. C57BL/6 mice were treated with scopolamine via intraperitoneal injection to simulate memory impairment. To determine the influence of SCP on the total acetylated-protein level of the hippocampus, acetylated-proteomics was performed. SCP increased the acetylation level of histone (H3 and H4). Meanwhile, for non-histones, the differentially acetylated proteins were involved in multiple memory-related pathways, as shown by KEGG enrichment analysis. Additionally, long-term potentiation was confirmed by western blotting. Finally, a combined analysis of proteome and lysine acetylome revealed that SCP contributed to synaptic vesicle cycle regulation and dopamine metabolism. Consequently, our findings revealed that SCP was potentially neuroprotective by regulating post-transcriptional hippocampal protein acetylation.