Compared of efficacy and safety of high-dose donepezil vs standard-dose donepezil among elderly patients with Alzheimer’s disease: a systemic review and meta-analysis

Inflammatory signaling pathways in the treatment of Alzheimer's disease with inhibitors, natural products and metabolites (Review)

The intricate nature of Alzheimer's disease (AD) pathogenesis poses a persistent obstacle to drug development. In recent times, neuroinflammation has emerged as a crucial pathogenic mechanism of AD, and the targeting of inflammation has become a viable approach for the prevention and management of AD. The present study conducted a comprehensive review of the literature between October 2012 and October 2022, identifying a total of 96 references, encompassing 91 distinct pharmaceuticals that have been investigated for their potential impact on AD by inhibiting neuroinflammation. Research has shown that pharmaceuticals have the potential to ameliorate AD by reducing neuroinflammation mainly through regulating inflammatory signaling pathways such as NF‑κB, MAPK, NLRP3, PPARs, STAT3, CREB, PI3K/Akt, Nrf2 and their respective signaling pathways. Among them, tanshinone IIA has been extensively studied for its anti‑inflammatory effects, which have shown significant pharmacological properties and can be applied clinically. Thus, it may hold promise as an effective drug for the treatment of AD. The present review elucidated the inflammatory signaling pathways of pharmaceuticals that have been investigated for their therapeutic efficacy in AD and elucidates their underlying mechanisms. This underscores the auspicious potential of pharmaceuticals in ameliorating AD by impeding neuroinflammation.

Functions and mechanisms of protein lysine butyrylation (Kbu): Therapeutic implications in human diseases

Post-translational modifications (PTM) are covalent modifications of proteins or peptides caused by proteolytic cleavage or the attachment of moieties to one or more amino acids. PTMs play essential roles in biological function and regulation and have been linked with several diseases. Modifications of protein acylation (Kac), a type of PTM, are known to induce epigenetic regulatory processes that promote various diseases. Thus, an increasing number of studies focusing on acylation modifications are being undertaken. Butyrylation (Kbu) is a new acylation process found in animals and plants. Kbu has been recently linked to the onset and progression of several diseases, such as cancer, cardiovascular diseases, diabetes, and vascular dementia. Moreover, the mode of action of certain drugs used in the treatment of lymphoma and colon cancer is based on the regulation of butyrylation levels, suggesting that butyrylation may play a therapeutic role in these diseases. In addition, butyrylation is also commonly involved in rice gene expression and thus plays an important role in the growth, development, and metabolism of rice. The tools and analytical methods that could be utilized for the prediction and detection of lysine butyrylation have also been investigated. This study reviews the potential role of histone Kbu, as well as the mechanisms underlying this process. It also summarizes various enzymes and analytical methods associated with Kbu, with the goal of providing new insights into the role of Kbu in gene regulation and diseases.

Ginsenoside Rg1 attenuates D-galactose-induced neural stem cell senescence via the Sirt1-Nrf2-BDNF pathway

With the ageing of society's population, neurodegenerative diseases have become an important factor affecting the quality of life and mortality in the elderly. Since its physiopathological processes are complex and the authorized medications have recently been shown to have several adverse effects, the development of safe and efficient medications is urgently needed. In this study, we looked at how ginsenoside Rg1 works to postpone neural stem cell ageing and brain ageing, giving it a solid scientific foundation for use as a therapeutic therapy for neurodegenerative diseases.

Mapping new pharmacological interventions for cognitive function in Alzheimer's disease: a systematic review of randomized clinical trials

Background and Objective: Alzheimer's disease (AD) is a progressive neurodegenerative disorder, that is, characterized by cognitive decline. To date, there are no effective treatments for AD. Therefore, the objective of this study was to map new perspectives on the effects of pharmacological treatment on cognitive function and the overall psychological state in patients with AD. Methods: Two independent researchers searched for randomized clinical trials (RCTs) exploring new pharmacological approaches related to cognition in Alzheimer's disease in adults from 2018 to 2023 in PubMed, Web of Science, Scopus, and Cochrane Library databases. A total of 17 RCTs were included in this review. Results: The results show that in recent years, new drugs have been tested in patients with Alzheimer's disease, including masitinib, methylphenidate, levetiracetam, Jiannao Yizhi, and Huannao Yicong formulas. Most studies have been conducted in populations with mild to moderate Alzheimer's disease. Conclusion: Although some of the drugs found suggested improvement in cognitive function, the scarcity of available studies highlights the need for further research in this area. Systematic review registration: [www.crd.york.ac.uk/prospero], identifier [CRD42023409986].

Targeting Sigma Receptors for the Treatment of Neurodegenerative and Neurodevelopmental Disorders

The sigma-1 receptor is a 223 amino acid-long protein with a recently identified structure. The sigma-2 receptor is a genetically unrelated protein with a similarly shaped binding pocket and acts to influence cellular activities similar to the sigma-1 receptor. Both proteins are highly expressed in neuronal tissues. As such, they have become targets for treating neurological diseases, including Alzheimer's disease (AD), Huntington's disease (HD), Parkinson's disease (PD), multiple sclerosis (MS), Rett syndrome (RS), developmental and epileptic encephalopathies (DEE), and motor neuron disease/amyotrophic lateral sclerosis (MND/ALS). In recent years, there have been many pre-clinical and clinical studies of sigma receptor (1 and 2) ligands for treating neurological disease. Drugs such as blarcamesine, dextromethorphan and pridopidine, which have sigma-1 receptor activity as part of their pharmacological profile, are effective in treating multiple aspects of several neurological diseases. Furthermore, several sigma-2 receptor ligands are under investigation, including CT1812, rivastigmine and SAS0132. This review aims to provide a current and up-to-date analysis of the current clinical and pre-clinical data of drugs with sigma receptor activities for treating neurological disease.

Preparation and evaluation of injectable microsphere formulation for longer sustained release of donepezil

In this study, donepezil-loaded PLGA and PLA microspheres (Dp-PLGA-M/Dp-PLA-M) and Dp-PLA-M wrapped in a polyethylene glycol-b-polycaprolactone (PC) hydrogel (Dp-PLA-M/PC) were prepared to reduce the dosing frequency of injections to treat Alzheimer's disease patients. Dp-PLGA-M and Dp-PLA-M with a uniform particle size distribution were repeatably fabricated in nearly quantitative yield and with high encapsulated Dp yields using an ultrasonic atomizer. The injectability and in vitro and in vivo Dp release, biodegradation, and inflammatory response elicited by the Dp-PLGA-M, Dp-PLA-M, and Dp-PLA-M/PC formulations were then compared. All injectable formulations showed good injectability with ease of injection, even flow, and no clogging using a syringe needle under 21-G. The injections required a force of <1 N. According to the biodegradation rate of micro-CT, GPC and NMR analyses, the biodegradation of Dp-PLA-M was slower than that of Dp-PLGA-M, and the biodegradation rate of Dp-PLA-M/PC was also slower. In the Dp release experiment, Dp-PLA-M sustained Dp for longer compared with Dp-PLGA-M. Dp-PLA-M/PC exhibited a longer sustained release pattern of two months. In vivo bioavailability of Dp-PLA-M/PC was almost 1.4 times higher than that of Dp-PLA-M and 1.9 times higher than that of Dp-PLGA-M. The variations in the Dp release patterns of Dp-PLGA-M and Dp-PLA-M were explained by differences in the degradation rates of PLGA and PLA. The sustained release of Dp by Dp-PLA-M/PC was attributed to the fact that the PC hydrogel served as a wrapping matrix for Dp-PLA-M, which could slow down the biodegradation of PLA-M, thus delaying the release of Dp from Dp-PLA-M. Dp-PLGA-M induced a higher inflammatory response compared to Dp-PLA-M/PC, suggesting that the rapid degradation of PLGA triggered a strong inflammatory response. In conclusion, Dp-PLA-M/PC is a promising injectable Dp formulation that could be used to reduce the dosing frequency of Dp injections.

Poor Translatability of Biomedical Research Using Animals - A Narrative Review

The failure rate for the translation of drugs from animal testing to human treatments remains at over 92%, where it has been for the past few decades. The majority of these failures are due to unexpected toxicity - that is, safety issues revealed in human trials that were not apparent in animal tests - or lack of efficacy. However, the use of more innovative tools, such as organs-on-chips, in the preclinical pipeline for drug testing, has revealed that these tools are more able to predict unexpected safety events prior to clinical trials and so can be used for this, as well as for efficacy testing. Here, we review several disease areas, and consider how the use of animal models has failed to offer effective new treatments. We also make some suggestions as to how the more human-relevant new approach methodologies might be applied to address this.