hydroxysafflor-yellow-a and Alzheimer-Disease

Chronic stress plays a critical role in the etiology of sporadic Alzheimer's disease (AD). However, there are currently no effective drugs that can target chronic stress to prevent AD. In this study, we explored the neuroprotective effect of hydroxysafflor yellow A (HSYA) against chronic mild stress (CMS)-induced memory impairments in mice and the underlying mechanism. The Morris water maze test showed that HSYA significantly reduced CMS-induced learning and memory impairments in mice. HSYA increased the expression of brain-derived neurotrophic factor (BDNF) and activated downstream tropomyosin-related kinase B (TrkB) and phosphatidylinositol 3-kinase (PI3K)/protein kinase B(Akt)/mammalian target of rapamycin (mTOR) signaling. HSYA decreased the expression of regulator of calcineurin 1-1L (RCAN1-1L) that could promote the activity of glycogen synthase kinase-3β (GSK-3β). HSYA also attenuated tau phosphorylation by inhibiting the activity of GSK-3β and cyclin-dependent kinase-5 (Cdk5). Our data indicated that HSYA has protective effects against CMS-induced BDNF downregulation, tau phosphorylation and memory impairments. HSYA may be a promising therapeutic candidate for AD by targeting chronic stress.

Topics: Alzheimer Disease; Animals; Brain-Derived Neurotrophic Factor; Calcium-Binding Proteins; Chalcone; Disease Models, Animal; Gene Expression Regulation; Glycogen Synthase Kinase 3; Humans; Learning Disabilities; Membrane Glycoproteins; Memory Disorders; Mice; Muscle Proteins; Neuroprotective Agents; Phosphatidylinositol 3-Kinases; Phosphorylation; Protein-Tyrosine Kinases; Quinones; TOR Serine-Threonine Kinases

Safflower yellow (SY) is the main effective component of Carthamus tinctorius L., and Hydroxysafflor yellow A (HSYA) is the single active component with the highest content in SY. SY and HSYA have been shown to have neuroprotective effects in several AD models. In this study, we aimed to clarify whether the effects of SY and HSYA on the learning and memory abilities of Aβ

Topics: Alzheimer Disease; Amyloid beta-Peptides; Animals; Cerebral Cortex; Chalcone; Dendritic Spines; Female; Glutamic Acid; Hippocampus; Learning; Male; Memory; Neuronal Plasticity; Neuroprotective Agents; Nootropic Agents; Peptide Fragments; Quinones; Rats, Sprague-Dawley; Synapses

Inflammation is an important contributor to the development of Alzheimer's disease (AD). Anti-inflammatory medication may offer promising treatment for AD. Hydroxy-safflor yellow A (HSYA), a chemical component of the safflower yellow pigments, has been reported to exert potent immunosuppressive effects. This study examined the anti-inflammatory effects of HSYA in Aβ₁₋₄₂-treated BV-2 microglia cells. The mRNA levels of IL-1β, IL-4, IL-10, TNF-α, COX-2 and iNOS were detected by real-time PCR. Western blotting was used to determine the protein expression of COX-2, TNF-α, iNOS, Janus Kinase 2 (JAK2), p-JAK2, signal transducers and activators of transcription 3 (STAT3) and p-STAT3. BV2-conditioned medium was used to treat SH-SY5Y cells and primary neuronal cells in indirect toxicity experiments. Cell viability and apoptosis were assessed using MTT assay and Annexin V/PI staining respectively. The results demonstrated that HSYA significantly reduced the expression of the pro-inflammatory mediators and inhibited Aβ₁₋₄₂-induced neuroinflammation. Moreover, HSYA protected primary cortical neurons and SH-SY5Y cells against microglia-mediated neurotoxicity. HSYA also enhanced the phosphorylation of JAK2/STAT3 pathway and inhibition of JAK2 by AG 490 attenuated the anti-inflammatory effects of HSYA. Overall, our findings suggested that HSYA inhibited Aβ₁₋₄₂-induced inflammation and conferred neuroprotection partially through JAK2/STAT3 pathway, indicating that HSYA could be a potential drug for the treatment of AD.

Topics: Alzheimer Disease; Amyloid beta-Peptides; Animals; Anti-Inflammatory Agents; Apoptosis; Cell Line; Chalcone; Humans; Inflammation; Microglia; Neurons; Neuroprotective Agents; Quinones; Signal Transduction

Beta-amyloid (Aβ)-mediated inflammation plays a critical role in the initiation and progression of Alzheimer׳s disease (AD). Anti-inflammatory treatment may provide therapeutic benefits. In this study, the effect of hydroxy-safflor yellow A (HSYA) on Aβ1-42-induced inflammation in AD mice was investigated and the underlying mechanisms were explored. Aβ1-42 was injected into bilateral hippocampi of mice to induce AD models in vivo. Spatial learning and memory of mice were investigated by the Morris water maze test. Activated microglia and astrocytes were examined by immunofluorescence staining for ionized calcium-binding adapter molecule-1 (Iba-1) and glial fibrillary acidic protein (GFAP). The mRNA of inflammatory cytokines were measured using real-time PCR. NF-κB p65 translocation was analyzed by western blotting and immunostaining. IκB and phosphorylation of JAK2 and STAT3 were tested by western blotting. The results showed that HSYA ameliorated the memory deficits in Aβ1-42-induced AD mice. HSYA suppressed Aβ1-42-induced activation of microglia and astrocytes and reduced the mRNA expression of pro-inflammatory mediators. HSYA up-regulated the JAK2/STAT3 pathway and inhibits the activation of NF-κB signaling pathways. Pharmacological inhibition of STAT3 by AG490 reversed the inactivation of p65 and anti-inflammatory effects of HSYA. In conclusion, these results suggest that HSYA protects Aβ1-42-induced AD model through inhibiting inflammatory response, which may involve the JAK2/STAT3/NF-κB pathway.

Topics: Alzheimer Disease; Amyloid beta-Peptides; Animals; Cells, Cultured; Chalcone; Inflammation; Janus Kinase 2; Male; Mice; Mice, Inbred ICR; Microglia; NF-kappa B; Peptide Fragments; Quinones; Signal Transduction; Spatial Learning; STAT3 Transcription Factor

Homocysteine (Hcy) could induce amyloid β (Aβ) accumulation, synaptic dysfunction, and memory impairment as seen in Alzheimer disease (AD), the most prevalent neurodegenerative disorder, which affects more than 25 million people worldwide. Here we investigated the protective effect of hydroxysafflor yellow A (HSYA) on Hcy-induced Aβ accumulation, synaptic dysfunction, and learning and memory deficits. Rats were randomly divided into four groups: Control group, which received normal saline (NS); Hcy group, which received a daily vena caudalis injection of Hcy (400 μg/kg per day); Hcy+HSYA group, which received the same amount of Hcy plus 6 mg/kg per day HSYA intraperitoneally; and HSYA group, which received 6 mg/kg per day HSYA intraperitoneally for 2 weeks. Results showed that simultaneous supplementation of HSYA significantly attenuated Aβ accumulation, improved synaptic function, and reversed Hcy-induced cognitive impairment. Our data suggest that HSYA might be a promising therapeutic candidate for attenuating Hcy-induced AD-like pathological and behavioral deficits.

Topics: Alzheimer Disease; Animals; Blotting, Western; Chalcone; Enzyme-Linked Immunosorbent Assay; Homocysteine; Male; Maze Learning; Memory Disorders; Quinones; Rats; Rats, Sprague-Dawley; Synapses