Both Alzheimer's disease (AD) and osteoporosis (OP) are common age‐associated degenerative diseases and are strongly correlated with clinical epidemiology. However, there is a lack of clear ...pathological relationship between the brain and bone in the current understanding. Here, it is found that young osteocyte, the most abundant cells in bone, secretes extracellular vesicles (OCYYoung‐EVs) to ameliorate cognitive impairment and the pathogenesis of AD in APP/PS1 mice and model cells. These benefits of OCYYoung‐EVs are diminished in aged osteocyte‐derived EVs (OCYAged‐EVs). Based on the self‐constructed OCY‐EVs tracer transgenic mouse models and the in vivo fluorescent imaging system, OCY‐EVs have been observed to be transported to the brain under physiological and pathological conditions. In the hippocampal administration of Aβ40 induced young AD model mice, the intramedullary injection of Rab27a‐shRNA adenovirus inhibits OCYYoung‐EVs secretion from bone and aggravates cognitive impairment. Proteomic quantitative analysis reveals that OCYYoung‐EVs, compared to OCYAged‐EVs, enrich multiple protective factors of AD pathway. The study uncovers the role of OCY‐EV as a regulator of brain health, suggesting a novel mechanism in bone‐brain communication.
It is found that the osteocyte‐derived extracellular vesicles (OCY‐EVs) isolated from young osteocytes can ameliorate cognitive impairment and pathogenies of AD, but not OCY‐EVs isolated from aged osteocytes. OCY‐EV can transfer to the brain under physiological and pathological conditions. The study uncovers the role of OCY‐EVs as a regulator of brain, suggesting a novel mechanism in bone‐brain communication.
Three new proton conductors with simple structures based on isolated olyoxometalate anions as well as protonated imidazole and benzimidazole, namely, NNU‐6–8, have been successfully prepared by ...hydrothermal reaction. We could control the number of proton sources by selecting different types and changing the charges of POM anions. The single crystal sample of NNU‐6 along a‐axis shows a highest proton conductivity of 1.91×10−2 S cm−1, which is two and three orders of magnitude higher than that of 2.42×10−4 and 8.90×10−5 S cm−1 along b‐ and c‐axes, respectively, due to the more unobstructed H‐bonding network and stronger π–π stacking between benzimidazole rings as proton‐transferring pathway along a‐axis than that along b and c axes. It is a straightforward model to understand the metaphysical proton‐conducting process, and this is the first time to put forward the idea that π–π stacking could assist proton transfer and be in favor of proton conduction, which has been demonstrated by calculating potential energy surfaces of proton transfer between benzimidazole molecules.
A single‐crystal proton‐conducting model based on isolated Stranberg‐type polyoxometalate anion and protonated benzimidazole, shows a high proton conductivity along the crystallographic a‐axis, which is two and three orders of magnitude higher than that along b‐ and c‐axes. This is the first report to establish a single‐crystal proton‐conducting model and clarify the contribution and influence of intermolecular weak interactions on the proton conduction.
Background and Purpose
Aspirin eugenol ester (AEE) is a new drug compound synthesized by combining aspirin with eugenol. It was reported to possess anti‐thrombotic, anti‐atherosclerotic, and ...anti‐oxidative effects. However, its molecular mechanism against oxidative injury is unclear. This study investigated how AEE affected the oxidative injury of vascular endothelial cells in vivo and in vitro.
Experimental Approach
A hamster model of atherosclerosis induced by a high fat diet (HFD) and an in vitro model of oxidative stress, H2O2‐induced apoptosis of HUVECs, were used to investigate the anti‐oxidative effects of AEE.
Key Results
AEE significantly reduced the stimulatory effect of HFD on malondialdehyde, the inhibitory effect of HFD on SOD activity and GSH/GSSG ratio, and the overexpression of inducible NOS (iNOS) in the aorta. In vitro, incubation of HUVECs with H2O2 led their apoptosis, dysfunctions of the NO systems (including increased iNOS activity, decreased endothelial NOS activity, and increased production of NO), an imbalance in calcium homeostasis and energy metabolism with an increase in intracellular free calcium and decrease in ATP, and a down‐regulation of Nrf2. In contrast, in the HUVECs pretreated with 1 μM AEE for 24 hr, the above adverse effects induced by H2O2 were significantly ameliorated. Moreover, the decrease in NO production and activity of iNOS induced by AEE was significantly attenuated in Nrf2‐inhibited HUVECs.
Conclusion and Implication
AEE protects vascular endothelial cells from oxidative injury by regulating NOS and Nrf2 signalling pathways. This suggests that AEE is a novel potential agent for the prevention of atherosclerosis.
Alzheimer's disease (AD) is a chronic and fatal neurodegenerative disease; accumulating evidence suggests that vitamin deficiency is associated with the risk of AD. However, studies attempting to ...elucidate the relationship between vitamins and AD varied widely.
This study aimed to investigate the relationship between serum vitamin levels and AD in a cohort of the Chinese population.
A total of 368 AD patients and 574 healthy controls were recruited in this study; serum vitamin A, B1, B6, B9, B12, C, D, and E were measured in all participants.
Compared with the controls, vitamin B2, B9, B12, D, and E were significantly reduced in AD patients. Lower levels of vitamin B2, B9, B12, D, and E were associated with the risk of AD. After adjusting for age and gender, low levels of vitamin B2, B9, and B12 were still related to the risk of AD. In addition, a negative correlation was determined between vitamin E concentration and Activity of Daily Living Scale score while no significant association was found between serum vitamins and age at onset, disease duration, Mini-Mental State Examination, and Neuropsychiatric Inventory Questionnaire score.
We conclude that lower vitamin B2, B9, B12, D, and E might be associated with the risk of AD, especially vitamin B2, B9, and B12. And lower vitamin E might be related to severe ability impairment of daily activities.
Malignant melanoma is aggressive and has a high mortality rate. Toll-like receptor 4 (TLR4) has been linked to melanoma growth, angiogenesis and metastasis. However, signal transduction mediated by ...TLR4 for driving melanoma progression is not fully understood. Signal transducer and activator of transcription 3 (STAT3) has been identified as a major oncogene in melanoma progression. We found: that TLR4 expression positively correlates with activation/phosphorylation of STAT3 in human melanoma samples; that TLR4 ligands activate STAT3 through MYD88 and TRIF in melanoma cells; and that intratumoral activation of TLR4 increases STAT3 activation in the tumor and promotes tumor growth, angiogenesis, epithelial-mesenchymal transition (EMT) and the formation of an immunosuppressive tumor microenvironment in mice. Further, we found that the effects mediated by activating TLR4 are weakened by suppressing STAT3 function with a dominant negative STAT3 variant in melanoma. Collectively, our work identifies STAT3 activation as a key event in TLR4 signaling-mediated melanoma progression, shedding new light on the pathophysiology of melanoma.
Hyperlipidemia caused by abnormal lipid metabolism has reached epidemic proportions. This phenomenon is also common in companion animals. Previous studies showed that AEE significantly improves ...abnormal blood lipids in hyperlipidemia rats and mice, but its mechanism is still not clear enough. In this study, the mechanism and potential key pathways of AEE on improving hyperlipidemia in mice were investigated through the transcriptome and proteome study of ApoE-/- mice liver and the verification study on high-fat HepG2 cells. The results showed that AEE significantly decreased the serum TC and LDL-C levels of hyperlipidemia ApoE-/- mice, and significantly increased the enzyme activity of CYP7A1. After AEE intervention, the results of mice liver transcriptome and proteome showed that differential genes and proteins were enriched in lipid metabolism-related pathways. The results of RT-qPCR showed that AEE significantly regulated the expression of genes related to lipid metabolism in mice liver tissue. AEE significantly upregulated the protein expression of CYP7A1 in hyperlipidemia ApoE-/- mice liver tissue. The results in vitro showed that AEE significantly decreased the levels of TC and TG, and improved lipid deposition in high-fat HepG2 cells. AEE significantly increased the expression of CYP7A1 protein in high-fat HepG2 cells. AEE regulates the expression of genes related to lipid metabolism in high-fat HepG2 cells, mainly by FXR-SHP-CYP7A1 and FGF19-TFEB-CYP7A1 pathways. To sum up, AEE can significantly improve the hyperlipidemia status of ApoE-/- mice and the lipid deposition of high-fat HepG2 cells, and its main pathway is probably the bile acid metabolism-related pathway centered on CYP7A1.
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•AEE decreased significantly TCH and LDL levels in ApoE-/- hyperlipidemia mice and in high-fat HepG2 cells.•The differential genes and protein of AEE intervention were enriched in lipid metabolism-related pathways.•AEE can improve hyperlipidemia including lipid deposition through the pathway of bile acid metabolism centered on CYP7A1.
Gallbladder cancer (GBC) is the most common malignant tumour of the biliary track system. Angiogenesis plays a pivotal role in the development and progression of malignant tumours. miR-143-3p acts as ...a tumour suppressor in various cancers. Their role in GBC is however less well defined. Here we show that the expression levels of miR-143-3p were decreased in human GBC tissues compared with the non-tumour adjacent tissue (NAT) counterparts and were closely associated with overall survival. We discovered that miR-143-3p was a novel inhibitor of tumour growth and angiogenesis in vivo and in vitro. Our antibody array, ELISA and PLGF rescue analyses indicated that PLGF played an essential role in the antiangiogenic effect of miR-143-3p. Furthermore, we used miRNA target-prediction software and dual-luciferase assays to confirm that integrin α6 (ITGA6) acted as a direct target of miR-143-3p. Our ELISA and western blot analyses confirmed that the expression of PLGF was decreased via the ITGA6/PI3K/AKT pathway. In conclusion, miR-143-3p suppresses tumour angiogenesis and growth of GBC through the ITGA6/PI3K/AKT/PLGF pathways and may be a novel molecular therapeutic target for GBC.
Oocyte maturation defect can lead to maternal reproduction disorder. NAMPT is a rate‐limiting enzyme in mammalian NAD+ biosynthesis pathway, which can regulate a variety of cellular metabolic ...processes including glucose metabolism and DNA damage repair. However, the function of NAMPT in porcine oocytes remains unknown. In this study, we showed that NAMPT involved into multiple cellular events during oocyte maturation. NAMPT expressed during all stages of porcine oocyte meiosis, and inhibition of NAMPT activity caused the cumulus expansion and polar body extrusion defects. Mitochondrial dysfunction was observed in NAMPT‐deficient porcine oocytes, which showed decreased membrane potential, ATP and mitochondrial DNA content, increased oxidative stress level and apoptosis. We also found that NAMPT was essential for spindle organization and chromosome arrangement based on Ac‐tubulin. Moreover, lack of NAMPT activity caused the increase of lipid droplet and affected the imbalance of lipogenesis and lipolysis. In conclusion, our study indicated that lack of NAMPT activity affected porcine oocyte maturation through its effects on mitochondria function, spindle assembly and lipid metabolism.
Based on the prodrug principle, aspirin eugenol ester (AEE) was synthesized, which can reduce the side effects of aspirin and eugenol. As a good candidate for new antithrombotic and anti-inflammatory ...medicine, it is essential to evaluate its preventive effect on thrombosis. Preventive effect of AEE was investigated in κ-carrageenan-induced rat tail thrombosis model. AEE suspension liquids were prepared in 0.5% sodium carboxymethyl cellulose (CMC-Na). AEE was administrated at the dosage of 18, 36 and 72 mg/kg. Aspirin (20 mg/kg), eugenol (18 mg/kg) and 0.5% CMC-Na (30 mg/kg) were used as control drug. In order to compare the effects between AEE and its precursor, integration of aspirin and eugenol group (molar ratio 1:1) was also designed in the experiment. After drugs were administrated intragastrically for seven days, each rat was injected intraperitoneally with 20 mg/kg BW κ-carrageen dissolved in physiological saline to induce thrombosis. The length of tail-thrombosis was measured at 24 and 48 hours. The blank group just was given physiological saline for seven days without κ-carrageenan administrated. The results indicated that AEE significantly not only reduced the average length of thrombus, PT values and FIB concentration, but also reduced the red blood cell (RBC), hemoglobin (HGB), hematocrit (HCT) and platelet (PLT). The effects of AEE on platelet aggregation and anticoagulant in vitro showed that AEE could inhibit adenosine diphosphate (ADP)-induced platelet aggregation as dose-dependence but no notable effect on blood clotting. From these results, it was concluded that AEE possessed positive effect on thrombosis prevention in vivo through the reduction of FIB, PLT, inhibition of platelet aggregation and the change of TT and PT values.
Primary liver cancer is a lethal cancer. The phosphatidylinositol 3-kinase (PI3K)–Akt–mammalian target of rapamycin (mTOR) pathway has been implicated in the pathogenesis of liver cancer. Gomisin N ...(GN), a lignan isolated from the dried fruits of Schisandra chinensis (Turca.) Baill., has been reported to reduce viability of, and induce apoptosis in, HepG2 liver cancer cells. In preadipocytes, GN was found to inhibit Akt activity. In the present study, Akt signaling-related anti-liver cancer mechanisms of GN were investigated. We confirmed that GN reduces cell viability of, and triggers apoptosis in, more liver cancer cell lines. Mechanistic studies revealed that GN lowers protein levels of phospho-PI3K (p85 tyrosine (Tyr)458), phospho-Akt (serine (Ser)473), and Akt downstream molecules Mcl-1 in HepG2 and HCCLM3 cells. Meanwhile, GN activates mTOR and inhibits ULK1 (a negative downstream effector of mTOR) activities. Activation of mTOR has been reported to suppress ULK1 activity and repress autophagy. Indeed, we observed that GN inhibits autophagy in liver cancer cells. In summary, we for the first time demonstrated that GN inhibits the PI3K–Akt pathway and regulates the mTOR–ULK1 pathway in liver cancer cells.
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