Intermittent hypoxia therapy ameliorates beta-amyloid pathology via TFEB-mediated autophagy in murine Alzheimer's disease.

BACKGROUND: Alzheimer's disease (AD) is the most prevalent neurodegenerative disorder. Impaired autophagy in plaque-associated microglia (PAM) has been reported to accelerate amyloid plaque deposition and cognitive impairment in AD pathogenesis. Recent evidence suggests that the transcription factor EB (TFEB)-mediated activation of the autophagy-lysosomal pathway is a promising treatment approach for AD. Moreover, the complementary therapy of intermittent hypoxia therapy (IHT) has been shown to upregulate autophagy and impart beneficial effects in patients with AD. However, the effect of IHT on PAM remains unknown. METHODS: 8-Month-old APP/PS1 mice were treated with IHT for 28 days. Spatial learning memory capacity and anxiety in mice were investigated. AD pathology was determined by the quantity of nerve fibers and synapses density, numbers of microglia and neurons, Aß plaque deposition, pro-inflammatory factors, and the content of Aß in the brain. TFEB-mediated autophagy was determined by western blot and qRT-PCR. Primary microglia were treated with oligomeric Aß 1-42 (oAß) combined with IHT for mechanism exploration. Differential genes were screened by RNA-seq. Autophagic degradation process of intracellular oAß was traced by immunofluorescence. RESULTS: In this study, we found that IHT ameliorated cognitive function by attenuating neuronal loss and axonal injury in an AD animal model (APP/PS1 mice) with beta-amyloid (Aß) pathology. In addition, IHT-mediated neuronal protection was associated with reduced Aß accumulation and plaque formation. Using an in vitro PAM model, we further confirmed that IHT upregulated autophagy-related proteins, thereby promoting the Aß autophagic degradation by PAM. Mechanistically, IHT facilitated the nuclear localization of TFEB in PAM, with TFEB activity showing a positive correlation with Aß degradation by PAM in vivo and in vitro. In addition, IHT-induced TFEB activation was associated with the inhibition of the AKT-MAPK-mTOR pathway. CONCLUSIONS: These results suggest that IHT alleviates neuronal damage and neuroinflammation via the upregulation of TFEB-dependent Aß clearance by PAM, leading to improved learning and memory in AD mice. Therefore, IHT may be a promising non-pharmacologic therapy in complementary medicine against AD.

Inhibition of Aß aggregates in Alzheimer's disease by epigallocatechin and epicatechin-3-gallate from green tea.

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by progressive accumulation of senile plaques, which are primarily composed of misfolded amyloid ß-peptide (Aß). Aß aggregates are believed to be a key factor in the pathogenesis of AD, affecting the nervous system in human body. The therapeutic potential of tea-derived polyphenolic compounds, (-)-epigallocatechin (EGC) and (-)-epicatechin-3-gallate (ECG), for AD was investigated by assessing their effects on the Cu2+/Zn2+-induced or self-assembled Aß40 aggregation using thioflavine T fluorescent spectrometry, inductively coupled plasma mass spectrometry, UV-Vis spectroscopy, transmission electron microscope, silver staining, immunohistochemistry, and immunofluorescence assays. EGC and ECG mildly bind to Cu2+ and Zn2+, and diminish the Cu2+- or Zn2+-induced or self-assembled Aß aggregates; they also modulate the Cu2+/Zn2+-Aß40 induced neurotoxicity on mouse neuroblastoma Neuro-2a cells by reducing the production of ROS. Metal chelating, hydrogen bonding or Van Der Waals force may drive the interaction between the polyphenolic compounds and Aß. The results demonstrate that green tea catechins EGC and ECG are able to alleviate the toxicity of Aß oligomers and fibrils. Particularly, ECG can cross the blood-brain barrier to reduce the Aß plaques in the brain of APP/PS1 mice, thereby protecting neurons from injuries. The results manifest the potential of green tea for preventing or ameliorating the symptoms of AD.

Development of ß-elemene and Cisplatin Co-Loaded Liposomes for Effective Lung Cancer Therapy and Evaluation in Patient-Derived Tumor Xenografts.

PURPOSE: ß-elemene and cisplatin combined chemotherapy currently is one of the most important settings available for lung cancer therapy in China. However, the clinical outcome is limited by their pharmacokinetic drawbacks. On the other hand, most of nanomedicines have failed in clinical development due to the huge differences between heterogeneous clinical tumor tissues and homogenous cell-derived xenografts. In this work, we fabricated a ß-elemene and cisplatin co-loaded liposomal system to effectively treat lung cancer. METHOD: In vitro cytotoxicity of co-loaded liposomes was studied by MTT, trypan and Hoechst/PI staining, and western blot in A549, A549/DDP, and LCC cells. In vivo antitumor efficacy was evaluated in cell-derived and clinically relevant patient-derived xenografts. RESULTS: Co-loaded liposomes were more cytotoxic to cancer cells, especially than the combination of single-loaded liposomes, benefiting from their simultaneous drug internalization and release. As a result, they exhibited desirable therapeutic outcome in both cell-derived and patient-derived xenografts. CONCLUSION: ß-elemene and cisplatin co-loaded liposomes are a clinically promising candidate for effective lung cancer therapy.

Ligustilide prevents cognitive impairment and attenuates neurotoxicity in D-galactose induced aging mice brain.

Ligustilide (LIG) is a principal active ingredient of traditional Chinese medicine, Radix Angelica sinensis, which has versatile pharmacological activities including neuroprotection. Previous studies have demonstrated that LIG has beneficial effects on cognition deficits associated with cerebral damage or neurodegenerative disorders. In present study, we investigated the neuroprotective effect of LIG on cognitive impairment and neurotoxicity in the brain of aging mouse induced by d-galactose (d-gal). The aging model mice were induced by subcutaneous (S.C.) injection of d-gal once daily for 8 weeks and LIG (80 mg/kg) was simultaneously administered orally. The Morris water maze (MWM) test was used to assess the spatial learning and memory abilities. The activity of Na(+)-K(+)-ATPase and the content of lipid peroxidation product malondialdehyde (MDA) in brain were examined. The levels of glial fibrillary acidic protein (GFAP), growth-associated protein GAP-43, and cleaved caspase-3 in brain were also determined by immunohistochemistry. The MWM test showed that LIG administration markedly improved behavioral performance of d-gal treated mice. This action could be partly explained by the results that LIG reduced the level of MDA as well as increased the activity of Na(+)-K(+)-ATPase in the brain of d-gal induced aging mice. Moreover, LIG significantly raised the expression of GAP-43 and reduced cleaved caspase-3 and GFAP levels in the brain of d-gal treated mice. These results demonstrated that LIG improves d-gal-induced cognitive dysfunction and brain toxicity, which suggests that LIG may be developed as a new medicine for the treatment of aged-related conditions.

Ligustilide alleviates brain damage and improves cognitive function in rats of chronic cerebral hypoperfusion.

ETHNOPHARMACOLOGICAL RELEVANCE: Ligustilide (LIG), a main lipophilic component of Danggui (Chinese Angelica root, Radix Angelica sinensis) which is a popular used herb to treat menstrual disorders in traditional chinese medicine, has been reported to possess some neuroprotective effects on permanent focal ischemia and transient forebrain ischemia. AIM OF THE STUDY: Based on previous work, we intended to investigate the protective effects of LIG on parietal cortex and hippocampus of rats in chronic cerebral hypoperfusion model. MATERIALS AND METHODS: Chronic cerebral hypoperfusion was induced by permanent, bilateral common carotid artery's occlusion (2VO). The rats were treated with LIG (80mg/kg, by oral) from the eighth day after surgery for seven consecutive days. Their spatial learning and memory abilities were assessed using the Morris water maze. After six days for maze test, rats were sacrificed. Coronal sections in cortex and hippocampus were stained with cresyl violet or labeled with NeuN (Neuronal Nuclei), MAP-2 (Microtubule-Associated Protein-2), Caspase-3 and GFAP (Glial Fibrillary Acidic Protein) antibodies. RESULTS: LIG treatment for seven days decreased escape latency and swimming distance of 2VO rats from the third day in maze tests, and increased percent time in the target quadrant. LIG prevented neuronal loss, dendrites damage and neuronal apoptosis in both parietal cortex and hippocampus of 2VO rats; and it also inhibited astrocytic activation and proliferation stimulated by hypoperfusion. CONCLUSIONS: These results demonstrate that LIG show obvious neuroprotective potential for treating chronic cerebral hypoperfusion injury, which may be attributed to its anti-apoptosis of neuron and anti-proliferation of astrocyte both in cortex and in hippocampus of 2VO rats. We suggest that LIG can be developed as an effective drugs for the prevention of vascular dementia (VD).