Acetylated tau exacerbates apoptosis by disturbing mitochondrial dynamics in HEK293 cells.

An increase in tau acetylation at K274 and K281 and abnormal mitochondrial dynamics have been observed in the brains of Alzheimer's disease (AD) patients. Here, we constructed three types of tau plasmids, TauKQ (acetylated tau mutant, by mutating its K274/K281 into glutamine to mimic disease-associated lysine acetylation), TauKR (non-acetylated tau mutant, by mutating its K274/K281 into arginine), and TauWT (wild-type human full-length tau). By transfecting these tau plasmids in HEK293 cells, we found that TauWT and TauKR induced mitochondrial fusion by increasing the level of mitochondrial fusion proteins. Conversely, TauKQ induced mitochondrial fission by reducing mitochondrial fusion proteins, exacerbating mitochondrial dysfunction and apoptosis. BGP-15 ameliorated TauKQ-induced mitochondrial dysfunction and apoptosis by improving mitochondrial dynamics. Our findings suggest that acetylation of K274/281 represents an important post-translational modification site regulating mitochondrial dynamics, and that BGP-15 holds potential as a therapeutic agent for mitochondria-associated diseases such as AD.

[Research Progress of Thalidomide and Its Derivatives in Treatment of Myelodysplastic Syndrome--Review].

Thalidomide and its derivatives have been used in the treatment of myelodysplastic syndrome (MDS) because of their anti-angiogenic and immunomodulatory effects. In recent years, some studies have found that thalidomide and its derivatives not only showed significant efficacy in lower-risk MDS patients with del (5q), but also showed advantages in non-del (5q) MDS patients. In addition, the discovery of its molecular targets and new substrates makes it possible to develop a new generation of immunomodulatory drugs (IMiDs) and to design IMiDs-based proteolysis-targeting chimeras. In this review, the new progress in mechanism and clinical application of thalidomide and its derivatives were summarized briefly, so as to provide a more scientific, reasonable and effective scheme to the treatment of MDS.

[Advances in the Action Mechanism of Classical Pathways IKKα and IKKß in Hematological Tumors and Drug Therapy Blocking Their Effect--Review].

In recent years, it is found that the classical IKKα and IKKß pathway were closely relates with hematological tumors, except the classical pathogenesis, moreover the classical IKKß pathway is deeply studied. The studies indicated that the IKKßis activated to phosphorylate the NF-κB through multiple cascades under the effect of extracellular IL-6, TNF-α and other stimulating factors. At the cellular level, the classical IKKßcan promote the tumor cell survival and proliferation, reduce the cell apoptosis, and promote the angiogenesis and cell transfer. Although the classical IKKα plays a role in regulating IKKß activity, but its role in non-classical pathway is more prominent. This review briefly summarizes the latest advance of researches on the pathogenesis of hematological malignancies in term of IKKα and IKKßpathway, so as to provide the theoretic basis for deeply understanding and studying the pathogenesis of hematologic tumors. At present, blocking the classical IKKα and IKKß pathway has become a new target for treatment of hematological tumors, moreover, some specific inhibitor for IKKα and IKKßpathway have been developed, for example, LY2409881, BMS 345541 and so on. Most of these drugs are in clinical trials and display some good anti-tumor effects.

Application of a combined model with seasonal autoregressive integrated moving average and support vector regression in forecasting hand-foot-mouth disease incidence in Wuhan, China.

Hand-foot-mouth disease (HFMD) is a serious public health problem with increasing cases and substantial financial burden in China, especially in Wuhan city. Hence, there is an urgent need to construct a model to predict the incidence of HFMD that could make the prevention and control of this disease more effective.The incidence data of HFMD of Wuhan city from January 2009 to December 2016 were used to fit a combined model with seasonal autoregressive integrated moving average (SARIMA) model and support vector regression (SVR) model. Then, the SARIMA-SVR hybrid model was constructed. Subsequently, the fitted SARIMA-SVR hybrid model was applied to obtain the fitted HFMD incidence from 2009 to 2016. Finally, the fitted SARIMA-SVR hybrid model was used to forecast the incidence of HFMD of the year 2017. To assess the validity of the model, the mean square error (MSE) and mean absolute percentage error (MAPE) between the actual values and predicted values of HFMD incidence (2017) were calculated.From 2009 to 2017, a total of 107636 HFMD cases were reported in Wuhan City, Hubei Province, and the male-to-female ratio is 1.60:1. The age group of 0 to 5 years old accounts for 95.06% of all reported cases and scattered children made up the large proportion (accounted for 56.65%). There were 2 epidemic peaks, from April to July and September to December, respectively, with an emphasis on the former. High-prevalence areas mainly emerge in Dongxihu District, Jiangxia District, and Hongshan District. SARIMA (1,0,1)(0,0,2)[12] is the optimal model given with a minimum Akaike information criterion (AIC) (700.71), then SVR model was constructed by using the optimum parameter (C = 100000, =0.00001, =0.01). The forecasted incidences of single SARIMA model and SARIMA-SVR hybrid model from January to December 2017 match the actual data well. The single SARIMA model shows poor performance with large MSE and MAPE values in comparison to SARIMA-SVR hybrid model.The SARIMA-SVR hybrid model in this study showed that accurate forecasting of the HFMD incidence is possible. It is a potential decision supportive tool for controlling HFMD in Wuhan, China.

The ERK1/2 pathway participates in the upregulation of the expression of mesenteric artery α1 receptors by intravenous tail injections of mmLDL in mice.

Minimally modified low density lipoprotein (mmLDL) is a risk factor for cardiovascular diseases. However, no studies examining the effect of mmLDL on vascular smooth muscle receptors have been released. The current study investigated the effect of mmLDL on the mesenteric artery α1 adrenoceptor and the molecular mechanisms. Mice were divided into the normal saline (NS), mmLDL, and mmLDL+U0126 groups. In the mmLDL+U0126 group, the animals were subjected to an intravenous tail injection of mmLDL and an intraperitoneal injection of U0126. Vascular tension caused by noradrenaline (NA) in mesenteric arteries was measured with a sensitive myograph system. The serum levels of oxLDL, TNF-α, and IL-1ß were detected using enzyme-linked immunosorbent assays. The expressions of the α1 adrenoceptor, the α2 adrenoceptor, TNF-α, IL-1ß, and pERK1/2 were detected using real-time polymerase chain reactions and Western blot analysis. Compared with the NS group, the mmLDL group exhibited a noticeably enhanced NA shrinkage dose-response curve and a significantly increased Emax value (P<0.01). Prazosin (α1 adrenoceptor antagonist) caused a noticeable right shift of the dose-response curve. U0126 inhibited the increases in the serum levels and vessel wall expression of IL-1ß and TNF-α and enhanced the NA shrinkage dose-response curve caused by mmLDL, as observed by a significantly decreased Emax value (P<0.01). It inhibited the increased α1 adrenoceptor expression caused by mmLDL. The serum levels of IL-1ß and TNF-α demonstrated a positive correlation with the NA-induced maximum shrinkage percentage. U0126 inhibited the mmLDL-induced increase in the pERK1/2 protein level in the vessel wall. In conclusion, mmLDL increased the serum levels of IL-1ß and TNF-α in vivo by activating the ERK1/2 pathway, which resulted in α1 receptor-mediated vasoconstriction and an increase in the expression of α1 adrenoceptor. The results of this study may provide new ideas for the prevention and cure of cardiovascular diseases in the future.

Characterization of membrane occupation and recognition nexus repeat containing 3, meiosis expressed gene 1 binding partner, in mouse male germ cells.

Mammalian spermatogenesis is a well-organized process of cell development and differentiation. Meiosis expressed gene 1 (MEIG1) plays an essential role in the regulation of spermiogenesis. To explore potential mechanisms of MEIG1's action, a yeast two-hybrid screen was conducted, and several potential binding partners were identified; one of them was membrane occupation and recognition nexus repeat containing 3 (MORN3). MORN3 mRNA is only abundant in mouse testis. In the testis, Morn3 mRNA is highly expressed in the spermiogenesis stage. Specific anti-MORN3 polyclonal antibody was generated against N-terminus of the full-length MORN3 protein, and MORN3 expression and localization was examined in vitro and in vivo. In transfected Chinese hamster ovary cells, the antibody specifically crossed-reacted the full-length MORN3 protein, and immunofluorescence staining revealed that MORN3 was localized throughout the cytoplasm. Among multiple mouse tissues, about 25 kDa protein, was identified only in the testis. The protein was highly expressed after day 20 of birth. Immunofluorescence staining on mixed testicular cells isolated from adult wild-type mice demonstrated that MORN3 was expressed in the acrosome in germ cells throughout spermiogenesis. The protein was also present in the manchette of elongating spermatids. The total MORN3 expression and acrosome localization were not changed in the Meig 1-deficient mice. However, its expression in manchette was dramatically reduced in the mutant mice. Our studies suggest that MORN3 is another regulator for spermatogenesis, probably together with MEIG1.

[Construction of a recombinant plasmid of BC022687 and identification of its expression and localization in CHO cells].

OBJECTIVE: To construct a mammalian expression plasmid of the BC022687 gene and investigate the expression and localization of the fusion protein in Chinese hamster ovary (CHO) cells. METHODS: The BC022687 coding sequence was amplified by polymerase chain reaction (PCR) and subcloned into the pEGFP-C1 vector carrying the gene of green fluorescence protein (GFP). After the target region was sequenced, the recombinant plasmid was transfected into CHO cells, and its expression in the CHO cells was determined by Western blot. The localization of GFP-tagged BC022687 in the CHO cells was observed by laser scanning confocal microscopy. RESULTS: BC022687 was successfully cloned into the mammalian expression vector pEGFP-C1, with the restriction fragment length of 950 bp. The expression of the fusion protein was confirmed, with the relative molecular weight of 64 000. The GFP-tagged BC022687 protein was mainly localized in the cytoplasm, and also presented in the centrioles in the transfected CHO cells. CONCLUSION: The successful construction of the plasmid expressing BC022687 in CHO cells has laid a foundation for further studies on the role of this protein in ciliogenesis.

[A cross-sectional study about the effects of residential exposure to power transmission line on human nervous system symptoms and hematology].

OBJECTIVE: To investigate the possible effects on nervous system and health condition under the exposure to electromagnetic field. METHODS: Take the resident around the power transmission line as the objects and were divided into 3 groups by the distance from the power transmission line 20 m, 100 m and 500 m, respectively. Some living conditions and health conditions were recorded by face-to-face the questionnaire survey, and Hematological indices of each groups were examined including IgG, IgM, leukocyte formulae, erythrocyte, hemoglobin and platelet. RESULTS: There was no significant difference in each group, according exposure of daily life, such as drinking and smoking (P > 0.05). Compared with the each distance groups, it was presented significant difference between the distance from the power transmission line and the incidence of headache or dizziness, insomnia and easy weary and so on (P < 0.05). In hematology aspect, with the horizontal distance from the power transmission line decreasing, PLT level of residents was reductive and the difference was statistically significant (P < 0.001), whereas leukocyte formulae, erythrocyte, hemoglobin, IgG and IgM had no significant difference among each group (P < 0.05). CONCLUSION: Closely exposure to electromagnetic field may induce headache and so on and decrease the level of PLT.

[Molecular epidemiological study on oxidative DNA damage among Hasake ethnic migrants in Shenzhen].

OBJECTIVE: To explore the relationship of migration and oxidative DNA damage by comparative study of oxidative DNA damage effects on people with different years of migration among Xinjiang Hasake ethnicity in Shenzhen. METHODS: Sixty Hasake residents in Shenzhen were selected, and were divided into three groups (n=20) according to the years of migration. Major changes of their life style were investigated. 8-hydroxy-2'-deoxyguanosine (8-OH-dG) levels in urine were analyzed, and comet assay of peripheral blood lymphocytes conducted. RESULTS: When comparing with the group having a shorter than 1 year of stay,a significant decrease of oliveira tail moment and tail/head length in comet assay in the >3 years group (P < 0.05) was observed 8-OH-dG level decreased significantly in 1-3 years group (P < 0.05) and >3 years group (P < 0.01). CONCLUSION: Our results suggested that life style changes which related to migration might reduce DNA damage in Hasake nationalities.

Arsenite-induced alterations in Ku70-deficient cells: a model to study genotoxic effects.

As one of three subunits of DNA-dependent protein kinase (DNA-PK), Ku70 protein plays an important role in repair of DNA double-strand breaks (DNA DSB). To further understand the functions of Ku70 protein and the mechanisms underlying arsenite-induced genotoxic effects, the effects of Ku70 deficiency were examined. The Ku70-deficient cell line HLFK and null vector cell line HLFC were established after recombinant plasmid of Ku70 gene antisense RNA and null pEGFP-C1 vector were transferred into human embryo lung fibroblasts (HLF) cells. Experiments were undertaken to detect DNA DSB damage by neutral single-cell gel electrophoresis assay (SCGE), chromosomal alterations by micronucleus test, and cell cycle progression by flow cytometry in HLFC and HLFK cells treated with control, 1, 2.5, 5, or 10 microM sodium arsenite for 2, 4, or 24 h, respectively. Western blot analysis results showed that Ku70 protein content in HLFK cells decreased to 38% of those in HLFC cells. The median lethal concentrations (LC50) of sodium arsenite to HLFC and HLFK cells for 24 h were 27.38 microM and 21.80 microM, respectively. Results of neutral SCGE assay showed that there were concentration-dependent increases in tail length of DNA DSB, in percent of cells with DNA DSB tails, and in severity of DNA DSB damage in HLFK and HLFC cells. The increases in these indices in HLFK cells were significantly higher than those found in HLFC cells exposed to similar amounts of metal. The ability of DNA DSB to repair in HLFK cells was less than that seen in HLFC cells. Sodium arsenite produced concentration-dependent elevation in micronuclei and abnormal nuclei formation. The Ku70-deficiency enhanced the susceptibility to chromosomal alterations induced by sodium arsenite. Low concentrations of sodium arsenite induced cell arrest at G1; however, at high concentrations of metal this G1 arrest effect disappeared. These results suggested that Ku70 protein plays an important role in repair of DNA DSB damage and for maintainance of genome stability.

[In vitro inhibitory effect of dibenzoxanthene CY-B12 on proliferation of tumor cell lines and its possible mechanisms].

BACKGROUND & OBJECTIVE: CY-B12, a new dibenzon-xanthene, has been synthesized recently. This study was to investigate the in vitro antiproliferative activity of CY-B12 and its possible mechanisms. METHODS: The inhibitory effects of CY-B12 on proliferation of gastric carcinoma cell line MGC803, nasopharyngeal carcinoma cell line CNE-2, oral epithelial carcinoma cell line KB-3-1, and lung cancer cell line Glc82 were assessed by MTT assay. Cell cycle distribution and apoptosis were detected by flow cytometry (FCM). Apoptotic morphology of CNE-2 cells was observed under fluorescent microscope after Hoechst33258 staining. The expression of cell cycle-related proteins Cdc25C, Cdc2, and Cyclin B1 were measured by Western blot. DNA damage was detected by single cell gel electrophoresis (SCGE). RESULTS: CY-B12 obviously inhibited the proliferation of MGC803, CNE-2, KB-3-1, and Glc82 cells; the IC(50) values were 7.51, 9.58, 8.84, and 15.99 micromol/L, respectively. After treatment of CY-B12, CNE-2 cells were arrested at G(2)/M phase; chromatin condensation, apoptotic bodies, and sub-G1 peak were observed in CNE-2 cells. The protein expression of Cdc25C in CNE-2 cells was down-regulated by CY-B12 in a dose-dependent mannerû whereas Cyclin B1 and Cdc2 were up-regulated by low dose of CY-B12, and down-regulated by high dose of CY-B12. CY-B12 induced DNA damage in CNE-2 cells in a dose-dependent manner. CONCLUSION: CY-B12 has potent in vitro antiproliferative activity, which may be exerted through breaking DNA, down-regulating cell cycle-related protein Cdc25C, and inducing cell cycle arrest and apoptosis.

[Genetic polymorphisms of nucleotide repair gene hMTH1 in southern Chinese Han population].

In order to study the genetic polymorphisms of nucleotide repair gene hMTH1 in southern Chinese Han population, the polymorphisms of the gene's promoter and its five exons among peripheral blood lymphocytes of 172 Chinese Han people were analyzed with polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) and DNA sequencing. The sequences of the promoter and exon 1 of hMTH1 gene were conserved. A T to C polymorphism was detected at the 73th base in exon 2. The genotype frequencies of TT and TC were 93.02% and 6.98%, respectively. The allelic frequencies of T and C were 96.51% and 3.49%, respectively. A T to C polymorphism was detected at codon 45 in exon 3, which was first reported. The genotype frequencies of TT and TC were 95.35% and 4.65%, respectively. The allelic frequencies of T and C were 97.67% and 2.33%, respectively. A G to A polymorphism was detected at codon 83 in exon 4. The genotype frequencies of GG and GA were 89.53% and 10.47%, respectively. The allelic frequencies of G and A were 94.77% and 5.23%, respectively. A C to T polymorphism was detected at codon 119 in exon 5. The genotype frequencies of CC and CT were 95.93% and 4.07%, respectively. The allelic frequencies of C and T were 97.97% and 2.03%, respectively.

[Effects of hydroquinone on DNA and nucleus damage in human embryo lung fibroblasts].

OBJECTIVE: To study DNA and nucleus damage in human embryo lung fibroblast (HLF) exposed to hydroquinone (HQ) and its genotoxicity. METHODS: HLF were treated with HQ (0, 10, 20, 40, 80 micro mol/L, respectively) for 3 h and DNA damage was detected by comet assay. HLF was also treated with the same concentrations of HQ for 1 h and micronucleus test was performed after they were cultured for 24 h. RESULTS: Comet assay showed that percentage of cells with tails in each groups treated with varied doses of HQ was 12%, 19%, 42%, 79% and 95%, respectively, with mean tail length of 7.87, 9.35, 11.03, 19.28 and 23.32 micro m, respectively, in an obvious dose-dependent manner (P < 0.05). Very significant increase in percentage of cells with tails and length of their comet tail were observed in those groups treated with HQ of 20, 40 and 80 micro mol/L (P < 0.01). And, proportion of high and severe DNA damage increased with dose of HQ. HQ could also induce formation of micronucleus and abnormal nucleus in all groups treated by varied doses of HQ, with rates of micronucleus and abnormal nucleus of 2%, 3%, 10%, 9% and 15%, and 6%, 7%, 16%, 27% and 28%, respectively, in a significant dose-dependent manner. There was significant increase in rates of micronuclei and abnormal nuclei in cells treated with HQ at doses of 20, 40 and 80 micro mol/L (P < 0.05). CONCLUSIONS: Exposure to HQ could cause DNA and nucleus damage inducing genotoxic effects on HLF.

[Construction of double-strand break repair protein hKu70 deficient cell strain and its biologic characters].

OBJECTIVE: To construct DNA double-strand break (DSB) repair protein hKu70 deficient cell strain and to observe its biological characters for studying the functions of hKu70 gene and the effects of occupational harmfulness factors on DSB repair. METHODS: Human lung fibroblasts (HLF) were transfected with the eukaryotic expression plasmids of hKu70 gene antisense RNA (pEGFP-C1-K) to construct hKu70 protein deficient cells (named as "HLFK"). The protein expression levels of hKu70 gene in HLFC and HLFK were detected by the Western blotting to estimate the effects of antisense inhibition. Morphology, growth character and growth status in soft agar of transfected HLFK were observed. RESULTS: pEGFP-C1-K vector was successfully expressed in HLF. The protein expression level of hKu70 gene in HLFK was decreased by 42% as compared with that in HLFC. No obvious changes of the biologic characters were observed in HLFK. CONCLUSION: The hKu70 protein deficient cell strain was successfully constructed. The hKu70 protein deficiency alone didn't induce obvious changes of the biological characters in HLFK.

[Construction of eukaryotic expression vector of hMTH1 gene antisense RNA].

OBJECTIVE: To construct pEGFP-C1-T vector, an eukaryotic expression plasmid of hMTH1 gene antisense RNA. METHODS: The conservative region of hMTH1 gene was amplified by RT-PCR after total RNA being extracted from human embryo lung fibroblast (HLF) and then cloned into pGEM-T vector. After the recombinant plasmid was certified by DNA sequencing, the conservative region of hMTH1 gene was inserted into pEGFP-C1 vector reversedly and pEGFP-C1-T vector was constructed. The efficiency of antisense inhibition was verified by Western blotting after cell transfection. RESULTS: 423 bp fragment including conservative region of hMTH1 gene was obtained by RT-PCR. After cloned by pGEM-T vector and certified by DNA sequencing, pEGFP-C1-T vector was successfully constructed by means of recombinant DNA technology. Additionally pEGFP-C1-T vector could efficiently decrease hMTH1 protein level by 46%. CONCLUSION: The efficient expression vector of hMTH1 gene antisense RNA, pEGFP-C1-T has been constructed successfully.