Graphdiyne nanoplatforms for photothermal-ferroptosis combination therapy against glioblastoma.

Glioblastoma (GBM) is one of the most malignant tumors of the central nervous system and has a poor prognosis. GBM cells are highly sensitive to ferroptosis and heat, suggesting thermotherapy-ferroptosis as a new strategy for GBM treatment. With its biocompatibility and photothermal conversion efficiency, graphdiyne (GDY) has become a high-profile nanomaterial. Here, the ferroptosis inducer FIN56 was employed to construct GDY-FIN56-RAP (GFR) polymer self-assembled nanoplatforms against GBM. GDY could effectively load FIN56 and FIN56 released from GFR in a pH-dependent manner. The GFR nanoplatforms possessed the advantages of penetrating the BBB and acidic environment-induced in situ FIN56 release. Moreover, GFR nanoplatforms induced GBM cell ferroptosis by inhibiting GPX4 expression, and 808 nm irradiation reinforced GFR-mediated ferroptosis by elevating the temperature and promoting FIN56 release from GFR. In addition, the GFR nanoplatforms were inclined to locate in tumor tissue, inhibit GBM growth, and prolong lifespan by inducing GPX4-mediated ferroptosis in an orthotopic xenograft mouse model of GBM; meanwhile, 808 nm irradiation further improved these GFR-mediated effects. Hence, GFR may be a potential nanomedicine for cancer therapy, and GFR combined with photothermal therapy may be a promising strategy against GBM.

Activation of vitamin D receptor inhibits Tau phosphorylation is associated with reduction of iron accumulation in APP/PS1 transgenic mice.

Vitamin D deficiency and iron accumulation are prevalent in the brains of Alzheimer's disease (AD) patients, however, whether Vitamin D has a role in the regulations of iron metabolism in the condition of AD remains unknown. Our previous studies revealed that vitamin D deficiency promotes ß-amyloid (Aß) deposition in the APP/PS1 mouse brains, while supplemented with a specific agonist of vitamin D receptor (VDR), paricalcitol (PAL), significantly reduced Aß production via promoting the lysosomal degradation of ß-site APP cleavage enzyme 1 (BACE1). In this study, our data suggested that activation of VDR by PAL significantly reduced the iron accumulation in the cortex and hippocampus of APP/PS1 mice through downregulation of Transferrin receptor (TFR) by reducing iron-regulatory protein 2 (IRP2) expression. Furthermore, activation of VDR effectively reduced the phosphorylations of Tau at Ser396 and Thr181 sites via inhibiting the GSK3ß phosphorylation (Tyr216). Taken together, our data suggest that activation of VDR could inhibit the phosphorylations of Tau possibly by repressing the iron accumulation-induced upregulation of GSK3ß activity in the brains of APP/PS1 mice. Thus, activation of VDR may be an effective strategy for treating AD.

Associations of Copper Intake with Bone Mineral Density and Osteoporosis in Adults: Data from the National Health and Nutrition Examination Survey.

Some studies have suggested an association between serum copper and bone density. Few studies have explored the association between copper intake and osteoporosis and bone mineral density (BMD). Our research aims to assess the associations of copper intake with the risk of osteoporosis in United States adults using the National Health and Nutritional Examination Surveys (NHANES). A total of 8224 individuals were included in our study. Osteoporosis was defined that BMD values surpass 2.5 standard deviations (SD) below the mean of the young adult reference group. Copper intake from diets and supplements was estimated by using two 24-h recall surveys. After adjustment for all the covariates of interest, the odds ratios (ORs) (95% confidence interval (CI)) between the risk of osteoporosis and total copper intake across quartiles 3 and 4 compared with quartile 1 were 0.48 (0.31-0.74) (P < 0.01) and 0.41 (0.26-0.65) (P < 0.01), respectively. The mean total femur BMD and total spine BMD of the highest dietary copper intake quartile (Cu 1.51 mg/d) was 0.03 g/cm2 and 0.02 g/cm2 greater than the lowest quartile. Our results indicate that dietary and total copper intake was positively associated with increasing BMD in US adults and negatively associated with the risk of osteoporosis in US adults.

Paricalcitol accelerates BACE1 lysosomal degradation and inhibits calpain-1 dependent neuronal loss in APP/PS1 transgenic mice.

BACKGROUND: Recent studies have revealed that vitamin D deficiency may increase the risk of Alzheimer's disease, and vitamin D supplementation may be effective strategy to ameliorate the neurodegenerative process in Alzheimer's disease patients. Paricalcitol (PAL), a low-calcemic vitamin D receptor agonist, is clinically used to treat secondary hyperparathyroidism. However, the potential application of PAL for treating neurodegenerative disorders remains unexplored. METHODS: The APP/PS1 mice were intraperitoneally injected with PAL or vehicle every other day for 15 weeks. The ß-amyloid (Aß) production was confirmed using immunostaining and enzyme linked immunosorbent assay. The underlying mechanism was verified by western blot and immunostaining in vivo and in vitro. FINDINGS: Long-term PAL treatment clearly reduced ß-amyloid (Aß) generation and neuronal loss in APP/PS1 transgenic mouse brains. PAL stimulated the expression of low-density lipoprotein receptor-related protein 1 (LRP1) possibly through inhibiting sterol regulatory element binding protein-2 (SREBP2); PAL also promoted LRP1-mediated ß-site APP cleavage enzyme 1 (BACE1) transport to late endosomes, thus increasing the lysosomal degradation of BACE1. Furthermore, PAL diminished 8-hydroxyguanosine (8-OHdG) generation in neuronal mitochondria via enhancing base excision repair (BER), resulting in the attenuation of calpain-1-mediated neuronal loss. INTERPRETATION: The present data demonstrate that PAL can reduce Aß generation through accelerating BACE1 lysosomal degradation and can inhibit neuronal loss through suppressing mitochondrial 8-OHdG generation. Hence, PAL might be a promising agent for treating Alzheimer's disease. FUND: This study was financially supported by the Natural Science Foundation of China (U1608282).

Dehydroandrographolide Inhibits Osteosarcoma Cell Growth and Metastasis by Targeting SATB2-mediated EMT.

BACKGROUND: The 12-hydroxy-14-dehydroandrographolide (DP) is a predominant component of the traditional herbal medicine Andrographis paniculata (Burm. f.) Nees (Acanthaceae). Recent studies have shown that DP exhibits potent anti-cancer effects against oral and colon cancer cells. OBJECTIVE: This investigation examined the potential effects of DP against osteosarcoma cell. METHODS: A cell analyzer was used to measure cell viability. The cell growth and proliferation were performed by Flow cytometry and BrdU incorporation assay. The cell migration and invasion were determined by wound healing and transwell assay. The expression of EMT related proteins was examined by Western blot analysis. RESULTS: In this study, we found that DP treatment repressed osteosarcoma (OS) cell growth in a dose-dependent manner. DP treatment significantly inhibited OS cell proliferation by arresting the cell cycle at G2/M phase. In addition, DP treatment effectively inhibited the migration and invasion abilities of OS cells through wound healing and Transwell tests. Mechanistic studies revealed that DP treatment effectively rescued the epithelialmesenchymal transition (EMT), while forced expression of SATB2 in OS cells markedly reversed the pharmacological effect of DP on EMT. CONCLUSION: Our data demonstrated that DP repressed OS cell growth through inhibition of proliferation and cell cycle arrest; DP also inhibited metastatic capability of OS cells through a reversal of EMT by targeting SATB2. These findings demonstrate DP's potential as a therapeutic drug for OS treatment.

Expression of inositol-requiring enzyme 1ß is downregulated in azoxymethane/dextran sulfate sodium-induced mouse colonic tumors.

Inflammatory bowel disease (IBD) is a risk factor in colon cancer. Endoplasmic reticulum (ER) stress is associated with IBD and cancer. In the current study an azoxymethane (AOM) and dextran sulfate sodium (DSS)-induced mouse colonic tumor model was established to analyze the expression of ER stress chaperone molecules. Female C57BL/6 mice were intraperitoneally injected with 12 mg/kg AOM. On the 7th day following AOM injection, mice were treated with 1% DSS supplemented to the drinking water for 7 days, then followed by 14 days of normal drinking water. The cycle of 7 days DSS plus 14 days normal water was repeated twice and colonic tumors were evaluated for their number and size. Mice in the control group were injected with saline and received normal drinking water for the course of the experiment. mRNA levels of cytokines, inositol-requiring enzyme (IRE)1α and 1ß, their downstream targets X-box binding protein (XBP)1u, XBP1s and mucin (MUC) 2 and interleukin (IL)-6, IL-8 and tumor necrosis factor (TNF)-α were detected by reverse transcription-quantitative polymerase chain reaction. IRE1α, IRE1ß and MUC2 protein expression was evaluated by immunohistochemistry, and IRE1α and IRE1ß levels were further assessed by western blot analysis. It was observed that tumors developed in the distal colon of mice treated with AOM/DSS. IL-6, IL-8 and TNF-α mRNA levels were significantly increased in mice of the tumor group compared with mice of the control group. There were no significant differences in IRE1α mRNA and protein expression between the two groups and XBP1s mRNA levels were increased in the tumor compared with the control group. IRE1ß and MUC2 mRNA levels were significantly decreased in the tumor compared with the control group (decreased by 42 and 30%, respectively). IRE1ß and MUC2 proteins were predominately expressed in colonic epithelial cells and expression was decreased in the tumor compared with the control group. In conclusion, the downregulation of IRE1ß and MUC2 may reduce the ability of colon tissues to resist inflammation, thus promoting the occurrence and development of colonic tumors.

α-Lipoic acid improves abnormal behavior by mitigation of oxidative stress, inflammation, ferroptosis, and tauopathy in P301S Tau transgenic mice.

Alzheimer's disease (AD) is the most common neurodegenerative disease and is characterized by neurofibrillary tangles (NFTs) composed of Tau protein. α-Lipoic acid (LA) has been found to stabilize the cognitive function of AD patients, and animal study findings have confirmed its anti-amyloidogenic properties. However, the underlying mechanisms remain unclear, especially with respect to the ability of LA to control Tau pathology and neuronal damage. Here, we found that LA supplementation effectively inhibited the hyperphosphorylation of Tau at several AD-related sites, accompanied by reduced cognitive decline in P301S Tau transgenic mice. Furthermore, we found that LA not only inhibited the activity of calpain1, which has been associated with tauopathy development and neurodegeneration via modulating the activity of several kinases, but also significantly decreased the calcium content of brain tissue in LA-treated mice. Next, we screened for various modes of neural cell death in the brain tissue of LA-treated mice. We found that caspase-dependent apoptosis was potently inhibited, whereas autophagy did not show significant changes after LA supplementation. Interestingly, Tau-induced iron overload, lipid peroxidation, and inflammation, which are involved in ferroptosis, were significantly blocked by LA administration. These results provide compelling evidence that LA plays a role in inhibiting Tau hyperphosphorylation and neuronal loss, including ferroptosis, through several pathways, suggesting that LA may be a potential therapy for tauopathies.

Ginsenoside­Rg5 induces apoptosis and DNA damage in human cervical cancer cells.

Panax ginseng is traditionally used as a remedy for cancer, inflammation, stress and aging, and ginsenoside­Rg5 is a major bioactive constituent of steamed ginseng. The present study aimed to evaluate whether ginsenoside­Rg5 had any marked cytotoxic, apoptotic or DNA­damaging effects in human cervical cancer cells. Five human cervical cancer cell lines (HeLa, MS751, C33A, Me180 and HT­3) were used to investigate the cytotoxicity of ginsenoside­Rg5 using a 3­(4,5­dimethylthiazol­2­yl)­2,5­diphenyltetrazolium bromide assay. Additionally, the effects of ginsenoside­Rg5 on the apoptosis of HeLa and MS751 cells were detected using DNA ladder assays and flow cytometry. DNA damage was assessed in the HeLa and MS751 cells using alkaline comet assays and by detection of γH2AX focus formation. The HeLa and MS751 cells were significantly more sensitive to ginsenoside­Rg5 treatment compared with the C­33A, HT­3 and Me180 cells. As expected, ginsenoside­Rg5 induced significant concentration­ and time­dependent increases in apoptosis. In addition, ginsenoside­Rg5 induced significant concentration­dependent increases in the level of DNA damage compared with the negative control. Consistent with the comet assay data, the percentage of γH2AX­positive HeLa and MS751 cells also revealed that ginsenoside­Rg5 caused DNA double­strands to break in a concentration­dependent manner. In conclusion, ginsenoside­Rg5 had marked genotoxic effects in the HeLa and MS751 cells and, thus, demonstrates potential as a genotoxic or cytotoxic drug for the treatment of cervical cancer.