Efficacy of probucol on cognitive function in Alzheimer's disease: study protocol for a double-blind, placebo-controlled, randomised phase II trial (PIA study)

The therapeutic potential of probucol and probucol analogues in neurodegenerative diseases

Neurodegenerative disorders present complex pathologies characterized by various interconnected factors, including the aggregation of misfolded proteins, oxidative stress, neuroinflammation and compromised blood-brain barrier (BBB) integrity. Addressing such multifaceted pathways necessitates the development of multi-target therapeutic strategies. Emerging research indicates that probucol, a historic lipid-lowering medication, offers substantial potential in the realm of neurodegenerative disease prevention and treatment. Preclinical investigations have unveiled multifaceted cellular effects of probucol, showcasing its remarkable antioxidative and anti-inflammatory properties, its ability to fortify the BBB and its direct influence on neural preservation and adaptability. These diverse effects collectively translate into enhancements in both motor and cognitive functions. This review provides a comprehensive overview of recent findings highlighting the efficacy of probucol and probucol-related compounds in the context of various neurodegenerative conditions, including Alzheimer's disease, Parkinson's disease, Huntington's disease, and cognitive impairment associated with diabetes.

Amyotrophic Lateral Sclerosis Mechanism: Insights from the Caenorhabditis elegans Models

Amyotrophic Lateral Sclerosis (ALS) is a debilitating neurodegenerative condition characterized by the progressive degeneration of motor neurons. Despite extensive research in various model animals, the cellular signal mechanisms of ALS remain elusive, impeding the development of efficacious treatments. Among these models, a well-characterized and diminutive organism, Caenorhabditis elegans (C. elegans), has emerged as a potent tool for investigating the molecular and cellular dimensions of ALS pathogenesis. This review summarizes the contributions of C. elegans models to our comprehension of ALS, emphasizing pivotal findings pertaining to genetics, protein aggregation, cellular pathways, and potential therapeutic strategies. We analyze both the merits and constraints of the C. elegans system in the realm of ALS research and point towards future investigations that could bridge the chasm between C. elegans foundational discoveries and clinical applications.

Probucol will become a new model for treating cerebral infarction with a high risk of hemorrhage: A narrative review

Lipid-lowering agents are relevant in stroke prevention. Probucol (PU) is an antioxidative and lipid-lowering drug that has been used to treat atherosclerotic cardiovascular diseases and xanthomas. The drug penetrates the core of low-density lipoprotein cholesterol (LDL-C) particles, enhancing the activity of plasma cholesterol l ester transfer protein (CETP) and strengthening the liver scavenger receptor type I, resulting in reducing LDL-C; by increasing the activity of paraoxonase 1, upregulating the antioxidant function of high-density lipoprotein (HDL), and it decreases the serum HDL-cholesterol (HDL-C) level. This drug has been retired from the Western markets for lowering HDL-C levels and Q-interval prolongation. The latter side effect has been rarely reported and may be transient. Recent clinical evidence supports the effectiveness of PU in preventing cardiovascular events and in reducing mortality, irrespective of the reduction of HDL-C. Based on basic research and clinical studies, it appears that PU might be a valuable alternative when statins are ineffective or contraindicated, in patients at high risk of recurrence of cerebral ischemia and hemorrhage.

Identification of Probucol as a candidate for combination therapy with Metformin for Type 2 diabetes

Type 2 Diabetes (T2D) is often managed with metformin as the drug of choice. While it is effective overall, many patients progress to exhibit complications. Strategic drug combinations to tackle this problem would be useful. We constructed a genome-wide protein-protein interaction network capturing a global perspective of perturbations in diabetes by integrating T2D subjects' transcriptomic data. We computed a 'frequently perturbed subnetwork' in T2D that captures common perturbations across tissue types and mapped the possible effects of Metformin onto it. We then identified a set of remaining T2D perturbations and potential drug targets among them, related to oxidative stress and hypercholesterolemia. We then identified Probucol as the potential co-drug for adjunct therapy with Metformin and evaluated the efficacy of the combination in a rat model of diabetes. We find Metformin-Probucol at 5:0.5 mg/kg effective in restoring near-normal serum glucose, lipid, and cholesterol levels.

Research and Progress of Probucol in Nonalcoholic Fatty Liver Disease

With the development of the social economy over the last 30 years, non-alcoholic fatty liver disease (NAFLD) is affected by unhealthy living habits and eating styles and has gradually become an increasingly serious public health problem. It is very important to investigate the pathogenesis and treatment of NAFLD for the development of human health. Probucol is an antioxidant with a bis-phenol structure. Although probucol is a clinically used cholesterol-lowering and antiatherosclerosis drug, its mechanism has not been elucidated in detail. This paper reviews the chemical structure, pharmacokinetics and pharmacological research of probucol. Meanwhile, this paper reviews the mechanism of probucol in NAFLD. We also analyzed and summarized the experimental models and clinical trials of probucol in NAFLD. Although current therapeutic strategies for NAFLD are not effective, we hope that through further research on probucol, we will be able to find suitable treatments to solve this problem in the future.

Is type 2 diabetes associated dementia a microvascular early-Alzheimer's phenotype induced by aberrations in the peripheral metabolism of lipoprotein-amyloid?

There is increasing evidence of a positive association of type 2 diabetes with Alzheimer's disease (AD), the most prevalent form of dementia. Suggested pathways include cerebral vascular dysfunction; central insulin resistance, or exaggerated brain abundance of potentially cytotoxic amyloid-β (Aβ), a hallmark feature of AD. However, contemporary studies find that Aβ is secreted in the periphery by lipogenic organs and secreted as nascent triglyceride-rich lipoproteins (TRL's). Pre-clinical models show that exaggerated abundance in blood of TRL-Aβ compromises blood-brain barrier (BBB) integrity, resulting in extravasation of the TRL-Aβ moiety to brain parenchyme, neurovascular inflammation and neuronal degeneration concomitant with cognitive decline. Inhibiting secretion of TRL-Aβ by peripheral lipogenic organs attenuates the early-AD phenotype indicated in animal models, consistent with causality. Poorly controlled type 2 diabetes commonly features hypertriglyceridemia because of exaggerated TRL secretion and reduced rates of catabolism. Alzheimer's in diabetes may therefore be a consequence of heightened abundance in blood of lipoprotein-Aβ and accelerated breakdown of the BBB. This review reconciles the prevailing dogma of amyloid associated cytotoxicity as a primary risk factor in late-onset AD, with substantial evidence of a microvascular axis for dementia-in-diabetes. Consideration of potentially relevant pharmacotherapies to treat insulin resistance, dyslipidaemia and by extension plasma amyloidemia in type 2 diabetes are discussed.

HDL-like-Mediated Cell Cholesterol Trafficking in the Central Nervous System and Alzheimer's Disease Pathogenesis

The main aim of this work is to review the mechanisms via which high-density lipoprotein (HDL)-mediated cholesterol trafficking through the central nervous system (CNS) occurs in the context of Alzheimer’s disease (AD). Alzheimer’s disease is characterized by the accumulation of extracellular amyloid beta (Aβ) and abnormally hyperphosphorylated intracellular tau filaments in neurons. Cholesterol metabolism has been extensively implicated in the pathogenesis of AD through biological, epidemiological, and genetic studies, with the APOE gene being the most reproducible genetic risk factor for the development of AD. This manuscript explores how HDL-mediated cholesterol is transported in the CNS, with a special emphasis on its relationship to Aβ peptide accumulation and apolipoprotein E (ApoE)-mediated cholesterol transport. Indeed, we reviewed all existing works exploring HDL-like-mediated cholesterol efflux and cholesterol uptake in the context of AD pathogenesis. Existing data seem to point in the direction of decreased cholesterol efflux and the impaired entry of cholesterol into neurons among patients with AD, which could be related to impaired Aβ clearance and tau protein accumulation. However, most of the reviewed studies have been performed in cells that are not physiologically relevant for CNS pathology, representing a major flaw in this field. The ApoE4 genotype seems to be a disruptive element in HDL-like-mediated cholesterol transport through the brain. Overall, further investigations are needed to clarify the role of cholesterol trafficking in AD pathogenesis.