Targeted Mitochondrial Epigenetics: A New Direction in Alzheimer's Disease Treatment.

Mitochondrial epigenetic alterations are closely related to Alzheimer's disease (AD), which is described in this review. Reports of the alteration of mitochondrial DNA (mtDNA) methylation in AD demonstrate that the disruption of the dynamic balance of mtDNA methylation and demethylation leads to damage to the mitochondrial electron transport chain and the obstruction of mitochondrial biogenesis, which is the most studied mitochondrial epigenetic change. Mitochondrial noncoding RNA modifications and the post-translational modification of mitochondrial nucleoproteins have been observed in neurodegenerative diseases and related diseases that increase the risk of AD. Although there are still relatively few mitochondrial noncoding RNA modifications and mitochondrial nuclear protein post-translational modifications reported in AD, we have reason to believe that these mitochondrial epigenetic modifications also play an important role in the AD process. This review provides a new research direction for the AD mechanism, starting from mitochondrial epigenetics. Further, this review summarizes therapeutic approaches to targeted mitochondrial epigenetics, which is the first systematic summary of therapeutic approaches in the field, including folic acid supplementation, mitochondrial-targeting antioxidants, and targeted ubiquitin-specific proteases, providing a reference for therapeutic targets for AD.

The prevalence of hypophosphatemia and refeeding-related hypophosphatemia in hospitalized patients requiring parental nutrition: a retrospective study.

OBJECTIVE: Hypophosphatemia might cause respiratory and heart failure and even death. We aimed to evaluate risk factors for hypophosphatemia and refeeding-related hypophosphatemia in patients requiring parental nutrition (PN). METHODS: This was a single-center, retrospective study. Clinical parameters were obtained from medical records. Serum phosphate (inorganic phosphorus) was measured by photometric analysis. Hypophosphatemia was confirmed when serum phosphate level was less than 0.8 mmol/L (≈2.5 mg/dl). Refeeding related hypophosphatemia was confirmed if serum phosphate level had a decrease of 0.16 mmol/L or more from baseline and if the final assessment was below 0.65 mmol/L. RESULTS: A total number of 655 (426 men and 229 women, aged 62.8 ± 14.8 years) hospitalized patients requiring PN were included in the study, and 60.6% of them were patients with cancer. The average body mass index (BMI) was 21.1 ± 4.1 kg/m2 and the median of serum phosphate was 0.9 mmol/L (quartile range: 0.68 mmol/L, 1.11 mmol/L). The prevalence of hypophosphatemia was 37.6% (246/655). Older age (≥ 65 years vs. < 65 years), lower serum level of pre-albumin (< 160 mg/L vs. ≥ 160 mg/L), calcium (< 2.11 mmol/L vs. ≥ 2.11 mmol/L), and magnesium (< 0.75 mmol/L vs. ≥ 0.75 mmol/L) were associated with high risk of hypophosphatemia by multivariate logistic regression (OR ranged from 1.43 to 3.06, all p < 0.05). Refeeding related hypophosphatemia was 9.5% (16/168). Serum level of calcium at baseline was significantly lower in participants with refeeding related hypophosphatemia than those without it. Total calorie and nitrogen delivered during first week of PN period showed no obvious difference between patients with and without refeeding related hypophosphatemia. CONCLUSIONS: Hypophosphatemia is common (37.6%) in hospitalized patients requiring PN. Monitoring of serum level of phosphorus is necessary to facilitate early treatment of hypophosphatemia.

Penicacids E-G, three new mycophenolic acid derivatives from the marine-derived fungus Penicillium parvum HDN17-478.

Three new mycophenolic acid derivatives, penicacids E-G (1-3), together with three known analogues, mycophenolic acid (4), 4'-hydroxy-mycophenolic acid (5) and mycophenolic methyl ester (6), were isolated from a marine-derived fungus Penicillium parvum HDN17-478 from a South China Sea marine sediment sample. The structures of compounds 1-3 were elucidated by HRMS, NMR, and Mosher's method. Among them, compounds 1 and 2 were the first examples of mycophenolic acid analogs with a double bond at C-3'/C-4' position. The cytotoxicity of 1-6 was evaluated against the HCT-116, BEL-7402, MGC-803, SH-SY5Y, HO-8910 and HL-60 cell lines, and compounds 4 and 6 showed potent cytotoxicity with IC50 values ranging from 1.69 to 12.98 µmol·L-1.

Glycyrrhizin Ameliorates Radiation Enteritis in Mice Accompanied by the Regulation of the HMGB1/TLR4 Pathway.

Radiation enteritis is a common side effect of radiotherapy for abdominal and pelvic malignancies, which can lead to a decrease in patients' tolerance to radiotherapy and the quality of life. It has been demonstrated that glycyrrhizin (GL) possesses significant anti-inflammatory activity. However, little is known about its anti-inflammatory effect in radiation enteritis. In the present study, we aimed to investigate the potential anti-inflammatory effects of GL on radiation enteritis and elucidate the possible underlying molecular mechanisms involved. The C57BL/6 mice were subjected to 6.5 Gy abdominal X-ray irradiation to establish a model of radiation enteritis. Hematoxylin and eosin staining was performed to analyze the pathological changes in the jejunum. The expression of TNF-α in the jejunum was analyzed by immunochemistry. The levels of inflammatory cytokines, such as TNF-α, IL-6, IL-1ß, and HMGB1 in the serum were determined by enzyme-linked immunosorbent assay. The intestinal absorption capacity was tested using the D-xylose absorption assay. The levels of HMGB1 and TLR4 were analyzed by western blotting and immunofluorescence staining. We found that GL significantly alleviated the intestinal damage and reduced the levels of inflammatory cytokines, such as TNF-α, IL-6, IL-1ß, and HMGB1 levels. Furthermore, the HMGB1/TLR4 signaling pathway was significantly downregulated by GL treatment. In conclusion, these findings indicate that GL has a protective effect against radiation enteritis through the inhibition of the intestinal damage and the inflammatory responses, as well as the HMGB1/TLR4 signaling pathway. Thereby, GL might be a potential therapeutic agent for the treatment of radiation enteritis.

Cell-based assays for Parkinson's disease using differentiated human LUHMES cells.

AIM: Lund human mesencephalic (LUHMES) cells can be differentiated to post-mitotic cells with biochemical, morphological and functional features of dopaminergic (DAergic) neurons. Given the limited scale of primary DAergic neuron culture, we developed differentiated LUHMES cell-based cytotoxicity assays for identifying neuroprotective agents for Parkinson's disease (PD). METHODS: LUHMES cells were incubated in a differentiation medium containing cAMP and GDNF for 6 d, and then differentiated cells were treated with MPP(+) or infected with baculovirus containing α-synuclein. Cytotoxicity was determined by measuring intracellular ATP levels and caspase 3/7 activity in the cells. DAergic neuron-specific marker protein and mRNA levels in the cells were analyzed using Western blotting and RT-PCR, respectively. RESULTS: LUHMES cells grew extensive neurites and became post-mitotic neuron-like cells during differentiation period, and three DAergic neuron markers TH, DAT and Nurr1 exhibited different expression profiles. MPP(+) dose-dependently reduced ATP levels in the cells with an IC50 value of 65 µmol/L. MPP(+) (80 µmol/L) significantly increased caspase 3/7 activity in the cells. Both the CDK inhibitor GW8510 and the GSK3ß inhibitor SB216763 effectively rescued MPP(+)-induced reduction of ATP levels with EC50 values of 12 and 205 nmol/L, respectively. Overexpression of α-synuclein also significantly decreased intracellular ATP levels and increased caspase 3/7 activity in the cells. GW8510 and SB216763 effectively rescued α-synuclein overexpression-induced reduction of ATP levels, whereas GW8510, but not SB216763, ameliorated α-synuclein overexpression-induced increase of caspase 3/7 activity. CONCLUSION: MPP(+)- and α-synuclein overexpression-induced cytotoxicity of differentiated LUHMES cells may serve as good alternative systems for identifying neuroprotective compounds for PD.

Lack of efficacy of Tai Chi in improving quality of life in breast cancer survivors: a systematic review and meta-analysis.

BACKGROUND: It is controversial whether Tai Chi (TC) benefits breast cancer survivors (BCS) on quality of life (QoL). We therefore undertook a meta-analysis to assess this question. MATERIALS AND METHODS: A computerized search through electronic databases was performed to identify relevant randomized controlled trials (RCTs). The primary outcome was QoL, while secondary outcomes included body mass index (BMI), bone mineral density (BMD), and muscle strength. RESULTS: Five RCTs involving 407 patients were included in the meta-analysis. The pooled standardized mean differences were 0.10 (95% confidence interval (CI): -0.35-0.54) for physical well- being, 0.03 (95%CI: -0.18-0.25) for social/family well-being, 0.24 (95%CI: 0.02-0.45) for emotional well-being, 0.23 (95%CI: -0.03-0.49) for functional well-being, and 0.09 (95%CI: -0.19-0.36) for additional concerns. TC failed to improve BMI, BMD, and muscle strength. CONCLUSIONS: There is currently lack of sufficient evidence to support TC improving QoL and other important clinical endpoints.

[Effects of hyperbaric oxygen combined with adriamycin in inducing apoptosis of K562/A02 cells].

This study was purposed to explore the effects of hyperbaric oxygen (HBO) combined with adriamycin (ADM) on inducing apoptosis of multidrug resistant cells line K562/A02. The cell apoptosis and expression of caspase-3 activity were analyzed by flow cytometry and transmission electron microscopy; the expression levels of HIF-1α, BCL-2 and BAX mRNA were detected by quantitative real time PCR; the caspase 8 activity was determined by using caspase 8 kit; the expression level of P-gp was detected by Western blot. The results showed that the apoptosis rate of K562/A02 cells in combination group (0.2 MPa HBO + ADM) was higher than that in ADM group [(47.36 ± 3.87) % vs (28.51 ± 1.09) %], the difference was statistical significant (p < 0.05); the expression levels of HIF-1α mRNA, P-gp and BCL-2 in combination group were lower than those in ADM group, there were significant differences (p < 0.05); the activities of BAX, caspase 3 and caspase 8 proteins in combination group were higher than those in ADM group, the difference was statistical significant (p < 0.05). It is concluded that 0.2 MPa HBO combined with ADM can reverse the drug-resistance of K562/A02 cells to ADM, enhance the apoptosis rate of cells. The molecular mechanism may be related with down-regulation of P-gp and BCL-2 expression, and up-regulation of caspase-3 and caspase-8 activities by HIF-1α.

Oxadiazole derivatives containing 1,4-benzodioxan as potential immunosuppressive agents against RAW264.7 cells.

A series of oxadiazole derivatives containing 1,4-benzodioxan (4a-4s) have been first synthesized for their potential immunosuppressive activity. Among the compounds, compound 4i showed the most potent biological activity against RAW264.7 cells (inhibition=37.66±2.34% for NO overproduction and IC(50)=0.05µM for iNOS). Docking simulation was performed to position compound 4i into the iNOS structure active site to determine the probable binding model. RT-PCR experiment results demonstrated that some of these compounds possessed good immunosuppressive activity against iNOS, especially for compound 4i. Therefore, compound 4i with potent inhibitory activity may be a potential agent.