tolfenamic-acid and Alzheimer-Disease

The field of Alzheimer's disease (AD) has witnessed recent breakthroughs in the development of disease-modifying biologics and diagnostic markers. While immunotherapeutic interventions have provided much-awaited solutions, nucleic acid-based tools represent other avenues of intervention; however, these approaches are costly and invasive, and they have serious side effects. Previously, we have shown in AD animal models that tolfenamic acid (TA) can lower the expression of AD-related genes and their products and subsequently reduce pathological burden and improve cognition. Using TA as a scaffold and the zinc finger domain of SP1 as a pharmacophore, we developed safer and more potent brain-penetrating analogs that interfere with sequence-specific DNA binding at transcription start sites and predominantly modulate the expression of SP1 target genes. More importantly, the proteome of treated cells displayed ~75% of the downregulated products as SP1 targets. Specific levels of SP1-driven genes and AD biomarkers such as amyloid precursor protein (APP) and Tau proteins were also decreased as part of this targeted systemic response. These small molecules, therefore, offer a viable alternative to achieving desired therapeutic outcomes by interfering with both amyloid and Tau pathways with limited off-target systemic changes.

Topics: Alzheimer Disease; Amyloid beta-Peptides; Amyloid beta-Protein Precursor; Animals; Mice; Mice, Transgenic; ortho-Aminobenzoates; tau Proteins

Tolfenamic acid, a nonsteroidal anti-inflammatory drug, alleviated learning and memory deficits and decreased the expression of specificity protein 1 (SP1)-mediated cyclin-dependent kinase-5 (CDK5), a major protein kinase that regulates hyperphosphorylated tau, in Alzheimer's disease (AD) transgenic mice. However, whether tolfenamic acid can regulate the major tau protein kinase, glycogen synthase kinase-3β (GSK-3β), or tau protein phosphatase, protein phosphatase 2A (PP2A), further inhibiting hyperphosphorylation of tau, remains unknown. To this end, tolfenamic acid was administered i.p. in a GSK-3β overactivation postnatal rat model and orally in mice after intracerebroventricular (ICV) injection of okadaic acid (OA) to develop a PP2A inhibition model. We used four behavioural experiments to evaluate memory function in ICV-OA mice. In this study, tolfenamic acid attenuated memory dysfunction. Tolfenamic acid decreased the expression of hyperphosphorylated tau in the brain by inhibiting GSK-3β activity, decreasing phosphorylated PP2A (Tyr307), and enhancing PP2A activity. Tolfenamic acid also increased wortmannin (WT) and GF-109203X (GFX) induced phosphorylation of GSK-3β (Ser9) and prevented OA-induced downregulation of PP2A activity in PC12 cells. Altogether, these results show that tolfenamic acid not only decreased SP1/CDK5-mediated tau phosphorylation, but also inhibited GSK-3β and PP2A-mediated tau hyperphosphorylation in AD models.

Topics: Alzheimer Disease; Animals; Anti-Inflammatory Agents, Non-Steroidal; Disease Models, Animal; Female; Glycogen Synthase Kinase 3 beta; Male; Mice; Mice, Inbred C57BL; ortho-Aminobenzoates; Phosphorylation; Protein Phosphatase 2; Rats; Rats, Wistar; tau Proteins

Topics: Alzheimer Disease; Amyloid beta-Peptides; Animals; Cell Line, Tumor; Cyclin-Dependent Kinase 5; Cyclooxygenase 2; Disease Models, Animal; Frontal Lobe; Humans; Memory; Mice, Knockout; ortho-Aminobenzoates; tau Proteins; Treatment Outcome

Tolfenamic acid is a nonsteroidal anti-inflammatory drug with neuroprotective properties, and it alleviates learning and memory deficits in the APP transgenic mouse model of Alzheimer's disease. However, whether tolfenamic acid can prevent motor and memory dysfunction in transgenic animal models of Huntington's disease (HD) remains unclear. To this end, tolfenamic acid was orally administered to transgenic R6/1 mice from 10 to 20 weeks of age, followed by several behavioral tests to evaluate motor and memory function. Tolfenamic acid improved motor coordination in R6/1 mice as tested by rotarod, grip strength, and locomotor behavior tests and attenuated memory dysfunction as analyzed using the novel object recognition test and passive avoidance test. Tolfenamic acid decreased the expression of mutant huntingtin in the striatum of 20-week-old R6/1 mice by inhibiting specificity protein 1 expression and enhancing autophagic function. Furthermore, tolfenamic acid exhibited antioxidant effects in both R6/1 mice and PC12 cell models. Collectively, these results suggest that tolfenamic acid has a good therapeutic effect on R6/1 mice, and may be a potentially useful agent in the treatment of HD.

Topics: Alzheimer Disease; Animals; Antioxidants; Behavior, Animal; Disease Models, Animal; Huntingtin Protein; Huntington Disease; Maze Learning; Memory Disorders; Mice; Mice, Transgenic; Mutation; ortho-Aminobenzoates; PC12 Cells; Psychomotor Performance; Rats

Environmental exposure to lead (Pb) early in life results in a latent upregulation of genes and products associated with Alzheimer's disease (AD), particularly the plaque forming protein amyloid beta (Aβ). Furthermore, animals exposed to Pb as infants develop cognitive decline and memory impairments in old age. Studies from our lab demonstrated that tolfenamic acid lowers the levels of the amyloid β precursor protein (APP) and its aggregative cleavage product Aβ by inducing the degradation of the transcription factor specificity protein 1 (Sp1). These changes were accompanied by cognitive improvement in transgenic APP knock-in mice. In this study, we examined the effects of tolfenamic acid on beta site APP cleaving enzyme 1 (BACE1) which is responsible for Aβ production and tested its ability to reverse Pb-induced upregulation in the amyloidogenic pathway. Mice were administered tolfenamic acid for one month and BACE1 gene expression as well as its enzymatic activity were analyzed in the cerebral cortex. Tolfenamic acid was also tested for its ability to reverse changes in Sp1, APP and Aβ that were upregulated by Pb in vitro. Differentiated SH-SY5Y neuroblastoma cells were either left unexposed, or sequentially exposed to Pb followed by tolfenamic acid. Our results show that tolfenamic acid reduced BACE1 gene expression and enzyme activity in mice. In neuroblastoma cells, Pb upregulated Sp1, APP and Aβ, while tolfenamic acid lowered their expression. These results along with previous data from our lab provide evidence that tolfenamic acid, a drug that has been used for decades for migraine, represents a candidate which can reduce the pathology of AD and may mitigate the damage of environmental risk factors associated with this disease.

Topics: Alzheimer Disease; Amyloid beta-Peptides; Amyloid beta-Protein Precursor; Amyloid Precursor Protein Secretases; Animals; Aspartic Acid Endopeptidases; Biomarkers; Cell Line, Tumor; Cell Survival; Cerebral Cortex; Female; Humans; Lead; Lead Poisoning, Nervous System; Mice; Mice, Transgenic; Neuroprotective Agents; ortho-Aminobenzoates; Sp1 Transcription Factor; Up-Regulation

Tolfenamic acid lowers the levels of the amyloid precursor protein (APP) and amyloid beta (Aβ) when administered to C57BL/6 mice by lowering their transcriptional regulator specificity protein 1 (SP1). To determine whether changes upstream in the amyloidogenic pathway that forms Aβ plaques would improve cognitive outcomes, we administered tolfenamic acid for 34 days to hemizygous R1.40 transgenic mice. After the characterization of cognitive deficits in these mice, assessment of spatial learning and memory functions revealed that treatment with tolfenamic acid attenuated long-term memory and working memory deficits, determined using Morris water maze and the Y-maze. These improvements occurred within a shorter period of exposure than that seen with clinically approved drugs. Cognitive enhancement was accompanied by reduction in the levels of the SP1 protein (but not messenger RNA [mRNA]), followed by lowering both the mRNA and the protein levels of APP and subsequent Aβ levels. These findings provide evidence that tolfenamic acid can disrupt the pathologic processes associated with Alzheimer's disease (AD) and are relevant to its scheduled biomarker study in AD patients.

Topics: Alzheimer Disease; Amyloid beta-Peptides; Amyloid beta-Protein Precursor; Animals; Cognition; Disease Models, Animal; Down-Regulation; Maze Learning; Memory Disorders; Memory, Long-Term; Memory, Short-Term; Mice; Mice, Inbred C57BL; Mice, Transgenic; Nootropic Agents; ortho-Aminobenzoates; Sp1 Transcription Factor

Evidence from our laboratory suggests that tolfenamic acid has a potential for slowing the progression of Alzheimer's disease (AD) through lowering cortical levels of the β-amyloid precursor protein (APP) and its pathogenic amyloid beta (Aβ) intermediates [1]. In this study, we examined the ability of tolfenamic acid to cross the blood brain barrier (BBB) by predicting its logBB and logPS values, the indexes of BBB permeability, using computational models. We also determined, via in vitro methods, the brain penetration capacity factor [(K(IAM)/MW(4))x10(10)] using phosphatidylcholine column chromatography. The obtained logBB, logPS and (K(IAM)/MW(4))x10(10) values predicted that tolfenamic acid can passively transfer into the central nervous system (CNS). These results were validated in vivo using LC-MS analysis after administration of tolfenamic acid intravenously to guinea pigs and mice. The present study provides the first evidence of the ability of tolfenamic acid to cross the BBB and offers a comparative analysis of approaches used to predict the ability of compounds to penetrate into the brain.

Topics: Alzheimer Disease; Animals; Anti-Inflammatory Agents, Non-Steroidal; Blood-Brain Barrier; Brain; Cell Membrane Permeability; Disease Models, Animal; Drug Evaluation, Preclinical; Guinea Pigs; Mice; Mice, Inbred C57BL; ortho-Aminobenzoates