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Mitochondrial dysfunction is considered an early event of Alzheimer disease (AD). D-ribose is a natural monosaccharide that exists in cells, especially in mitochondria, and can lead to cognitive dysfunction. However, the reason for this is unclear. Berberine (BBR) is an isoquinoline alkaloid that can target mitochondria and has great prospect in the treatment of AD. The methylation of PINK1 reinforces the burden of Alzheimer's pathology. This study explores the role of BBR and D-ribose in the mitophagy and cognitive function of AD related to DNA methylation. APP/PS1 mice and N2a cells were treated with D-ribose, BBR, and mitophagy inhibitor Mdivi-1 to observe their effects on mitochondrial morphology, mitophagy, neuron histology, AD pathology, animal behavior, and PINK1 methylation. The results showed that D-ribose induced mitochondrial dysfunction, mitophagy damage, and cognitive impairment. However, BBR inhibition of PINK1 promoter methylation can reverse the above effects caused by D-ribose, improve mitochondrial function, and restore mitophagy through the PINK1–Parkin pathway, thus reducing cognitive deficits and the burden of AD pathology. This experiment puts a new light on the mechanism of action of D-ribose in cognitive impairment and reveals new insights in the use of BBR for AD treatment. [ABSTRACT FROM AUTHOR]

Objective: To investigate the effects of sport stacking on the overall cognition and brain function in patients with mild Alzheimer's disease (AD) and mild cognitive impairment (MCI). Methods: A single-blind randomized controlled design was performed using sport stacking for 30 min, 5 days/week for 12 weeks. Forty-eight subjects with mild AD or MCI were randomly divided into the sport stacking group (T-mAD = 12, T-MCI = 12) and the active control group (C-mAD = 11, C-MCI = 13). Auditory Verbal Learning Test (AVLT), Alzheimer's Disease Cooperative Study–Activities of Daily Living scale (ADCS-ADL), Geriatric Depression Scale (GDS-30), and Pittsburgh Sleep Quality Index (PSQI) were performed, the level of amyloid β-protein-40 (Aβ-40), Aβ-42, brain-derived neurotrophic factor (BDNF), insulin-like growth factor-1(IGF-1), tumor necrosis factor-alpha (TNF-α), Interleukin-6 (IL-6), and soluble trigger receptor expressed on myeloid cells 2 (sTREM2) in plasma were tested, and brain functional connectivity in resting state and activation under finger movement task were analyzed by functional near-infrared spectroscopy (fNIRS). Results: Thirty-nine patients completed the trial. After 4 weeks, we found a significant increase in AVLT score in T-MCI (6.36 ± 5.08 vs. −1.11 ± 4.23, p = 0.004), and T-mAD group (4.60 ± 4.77 vs. −0.11 ± 2.89, p = 0.039). After 12 weeks, there was a significantly improved in AVLT (9.64 ± 4.90 vs. −0.33 ± 6.10, p = 0.002) and ADCS-ADL (3.36 ± 3.59 vs. −1.89 ± 2.71, p = 0.003) in T-MCI. There was a significant improvement in AVLT (5.30 ± 5.42 vs. 0.44 ± 2.40) in T-mAD (p < 0.05). Plasma levels of BDNF were upregulated in both T-MCI and T-mAD, and IGF-1 increased in T-MCI (P < 0.05) compared to the control groups. The functional connectivity in MCI patients between DLPFC.R and SCA.R, SMA.L, and SCA.R was decreased. In contrast, in mAD patients, the brain regional function connection was increased between DLPFC.R and Broca's.L. The activation of channel 36 located in the left primary somatosensory cortex was significantly increased after 12-week training, which was correlated with the improved AVLT and the increase of BDNF. Conclusion: Our findings suggested that sport stacking is effective for patients with MCI and mild AD, possibly through increasing the expression of neuroprotective growth factors and enhancing neural plasticity to improve neurocognitive performance. Clinical Trial Registration: https://www.ClinicalTrials.gov, ChiCTR.org.cn, identifier: ChiCTR-2100045980. [ABSTRACT FROM AUTHOR]

Discovery of drugs rapidly and effectively is an important aspect for Alzheimer's disease (AD). In this study, a novel high-throughput screening (HTS) method aims at screening the small-molecules with amyloid- β (A β) binding affinity from natural medicines, based on the combinational use of biolayer interferometry (BLI) and ultra-high-performance liquid chromatography coupled with diode-array detector and quadrupole/time-of-flight tandem mass spectrometry (UHPLC−DAD-Q/TOF-MS/MS) has been firstly developed. Briefly, the components in natural medicines disassociated from biotinylated A β were collected to analyze their potential A β binding affinity by UHPLC−DAD-Q/TOF-MS/MS. Here, baicalein was confirmed to exhibit the highest binding affinity with A β in Scutellaria baicalensis. Moreover, polyporenic acid C (PPAC), dehydrotumulosic acid (DTA), and tumulosic acid (TA) in Kai-Xin-San (KXS) were also identified as potent A β inhibitors. Further bioactivity validations indicated that these compounds could inhibit A β fibrillation, improve the viability in A β -induced PC-12 cells, and decrease the A β content and improve the behavioral ability in Caenorhabditis elegans. The molecular docking results confirmed that PPAC, DTA, and TA possessed good binding properties with A β. Collectively, the present study has provided a novel and effective HTS method for the identification of natural inhibitors on A β fibrillation, which may accelerate the process on anti-AD drugs discovery and development. A high-throughput screening (HTS) method based on the combinational use of biolayer interferometry (BLI) and UHPLC‒DAD-Q/TOF-MS/MS is developed. PPAC, DTA, and TA are identified from Kai-Xin-San as potent A β inhibitors. [Display omitted] [ABSTRACT FROM AUTHOR]

Raddeanin A is a triterpenoid isolated from Anemone raddeana Regel. It exhibits a broad spectrum of biological activities such as anti-tumor and anti-inflammatory, however, its neuroprotective effect in targeting Alzheimer's disease (AD) remains uninvestigated. To provide scientific base for the development of novel AD drug by clarifying the neuroprotective effect and molecular mechanisms of raddeanin A in both in vitro and in vivo AD model. To confirm the neuroprotective role of raddeanin A in the treatment of AD, its mechanisms and effects on β-amyloidosis and Aβ fibrillation was studied in U87 cells. Besides, the improvement on cognitive deficit, pathological defects, reactive astrocyte clusters, inhibition on neuronal inflammation and apoptosis were further studied in 3 x Tg-AD mice model of AD. Real-time PCR, western blot, dot blot, biolayer interferometry and bioinformatics analysis were used to confirm the in vitro effect and targets of raddeanin A on β-amyloidosis and its associated protein network. A series of experiments including Morris water maze, H&E staining, nissl staining and immunofluorescence analysis were conducted to confirm the protective behavioral effect of raddeanin A in the in vivo AD mice model. Raddeanin A was identified to reduce β-amyloidosis in U87 cells and 3 x Tg-AD mice model of AD by decreasing level of BACE1, APP, APP-β and Aβ. Raddeanin A improved behavioral, spatial memory and learning ability in the AD mice. In the cortex and hippocampus, raddeanin A improved the morphology and arrangement of neurons, lower the level of reactive astrocyte marker GFAP and apoptotic marker proteins Bax/Bcl2 ratio. Moreover, raddeanin A upregulated the mRNA and protein level of Prkcα in the hippocampus of AD mice whose neuroprotective effect was exerted possibly via the activation of protein kinase C. As a novel natural agent targeting β-amyloidosis, our results provide the first evidence of the multiple in vitro and in vivo neuroprotective effect of raddeanin A, suggesting its potential therapeutic application in preventing or alleviating the symptoms of AD. [Display omitted] [ABSTRACT FROM AUTHOR]