[Clinical characteristics of patients infected with 2019-nCoV Omicron variants BA.2 and BA.5 in Xi'an city, China].

Objective: To analyze the epidemiological and clinical characteristics of patients infected with different subtype of 2019-nCoV Omicron variants BA.2 and BA.5 in Xi'an city. Methods: A retrospective observational study was conducted to collect data of 168 patients infected with Omicron variant admitted to the designated hospital for COVID-19 charged by Xi'an Chest Hospital during 2022. Data were collected including epidemiological, clinical features, laboratory and viral load, and the difference between BA.2 and BA.5 subtype was analyzed. Results: A total of 168 patients were admitted, including 122 cases infected with BA.2 subtype, and 46 cases infected with BA.5 subtype. Patients infected with BA.2 subtype had a higher rate of cough than BA.5 subtype (43.44%∶23.91%; P=0.021). Compared with the Omicron variant BA.2, patients infected with BA.5 subtype had a higher proportion of asymptomatic and mild infections (89.13%∶68.85%; P<0.001), higher rate of vaccination (95.66%∶68.03%; P<0.001), shorter time to nucleic acid negative conversion (8.62; P=0.047), and a higher viral load at admission (P=0.005, P=0.017). Conclusions: The Omicron variant is extremely infectious with aggregated onset, but its clinical symptoms are mild. The vaccine, especially the booster vaccination, remains effective in preventing severe stage progression and improving prognosis in patients with Omicron variant infection.

Tudor knockdown disrupts ovary development in Bactrocera dorsalis.

One of the main functions of the piwi-interacting RNA pathway is the post-transcriptional silencing of transposable elements in the germline of many species. In insects, proteins belonging to the Tudor superfamily proteins belonging to the Tudor superfamily play an important role in to play an important role in this mechanism. In this study, we identified the tudor gene in the oriental fruit fly, Bactrocera dorsalis, investigated the spatiotemporal expressional profile of the gene, and performed a functional analysis using RNA interference. We identified one transcript for a tudor homologue in the B. dorsalis transcriptome, which encodes a protein containing the typical 10 Tudor domains and an Adenosine triphosphate (ATP) synthase delta subunit signature. Phylogenetic analysis confirmed the identity of this transcript as a tudor homologue in this species. The expression profile indicated a much higher expression in the adult and pupal stages compared to the larval stages (up to a 60-fold increase), and that the gene was mostly expressed in the ovaries, Malpighian tubules and fat body. Finally, gene knockdown of tudor in B. dorsalis led to clearly underdeveloped ovaries in the female adult and reductions in copulation rate and amount of oviposition, indicating its important role in reproduction. The results of this study shed more light on the role of tudor in ovary development and reproduction.

Vitellogenin and its receptor play essential roles in the development and reproduction of the brown citrus aphid, Aphis (Toxoptera) citricidus.

Vitellogenin (Vg) and its receptor (VgR) play a key role in the reproductive process and development of insects. Aphids are a group of high-fecundity insect species with pseudoplacental viviparity, but the roles of their Vg and VgR genes have not been investigated yet. The brown citrus aphid, Aphis (Toxoptera) citricidus, is a major insect pest of citrus and the main vector of Citrus tristeza closterovirus. In this study, we identified and characterized these two genes, designated as AcVg and AcVgR, from the brown citrus aphid. We found that AcVg has lost the DUF1943 domain that is present in other insect Vgs. Silencing of AcVg and AcVgR led to a delay in the nymph-adult transition, a prolonged prereproductive period, and a shortened reproductive period, which in turn resulted in slower embryonic development and fewer new-born nymphs. Interestingly, silencing of AcVg decreased the transcript level of AcVgR, but silencing of AcVgR resulted in increased transcript levels of AcVg. In addition, silencing of Vg/VgR had similar phenotypes between alate and apterous morphs, suggesting that the functions of these two genes are the same in the two wing morphs of the aphid. Our results demonstrate that Vg and VgR are involved in various aspects of aphid development and reproduction. Further studies on the synthesis of Vg could help to elucidate the reproductive mechanism and provide information that will be useful for developing new pest control strategies.

Identification, characterization and functional analysis of a chitin synthase gene in the brown citrus aphid, Toxoptera citricida (Hemiptera, Aphididae).

Chitin synthase (CHS) is a crucial enzyme involved in the final step of the insect chitin biosynthetic pathway. In this study, we cloned the full-length cDNA sequence of a chitin synthase gene (TCiCHS) from the brown citrus aphid, Toxoptera citricida, an important citrus pest and the main vector of citrus tristeza virus worldwide. TCiCHS was expressed during the entire lifecycle and in all insect tissues examined. Expression was highest in first-second-instar nymphs, nymph-adult transitions and in the abdomen (6.7-fold higher than head). Embryos had a higher expression level than the integument. Fourth-instar nymphs were exposed to 5 and 500 mg/l concentrations of the chitin synthesis inhibitor diflubenzuron (DFB) for 48 h and had the highest mortality at the 500 mg/l concentration. The mRNA expression levels of TCiCHS were significantly enhanced upon the exposure of nymphs to both low and high DFB concentrations. Silencing of TCiCHS occurred through plant-mediated double-stranded RNA (dsRNA) feeding. Most dsRNA-fed nymphs were unable to moult to the next stage, and the expression of TCiCHS decreased 48% compared with controls. These results demonstrate that TCiCHS plays an important role in nymph to adult development, is possibly help identify molecular targets for To. citricida control.

Chondroitinase administration and pcDNA3.1-BDNF-BMSC transplantation promote motor functional recovery associated with NGF expression in spinal cord-transected rat.

STUDY DESIGN: We evaluated whether combination of chondroitinase (chABC) administration and brain-derived neurotrophic factor (BDNF)-mesenchymal stem cell (MSC) transplantation could provide an optimal effect for the treatment of spinal cord injury (SCI) subjected to complete transection. OBJECTIVES: Behavioral assessments and DBA tracing were used to evaluate the effects of combination of chABC administration and BDNF-MSC transplantation on axonal regeneration and functional improvement in SCT rats. SETTING: Sichuan, ChinaMethods:Bone mesenchymal stem cells (BMSCs) were cultured and overexpressed BDNF recombinant vector was constructed into MSCs, then transplanted into the impaired spinal cord, together with chABC administration. Finally, the cortical spinal tract regeneration was detected by DBA tracing at 4 weeks post operation, and the expression of nerve growth factor (NGF), BDNF, neurotrophic factor (NT)-3, NT-4, fibroblast growth factor (FGF-2)-2, B cell lymphoma 2 (BCL-2) assaciated X protein (BAX) and BCL-2 in the caudal cord tissues was assessed by reverse transcription-PCR. RESULTS: Animals received both BDNF-BMSC transplantation and chABC administration presented the best functional recovery and obvious axonal regeneration. Moreover, NGF expression was significantly higher than that in the other groups. CONCLUSION: Co-treated strategy could effectively promote motor functional recovery and axonal regeneration in SCT rats associated with NGF upregulation.

Isolation and characterization of microsatellite markers for Dendranthema morifolium (Asteraceae) using next-generation sequencing.

Dendranthema morifolium (Asteraceae) is a perennial herbaceous plant native to China. A long history of artificial crossings may have resulted in complex genetic background and decreased genetic diversity. To protect the genetic diversity of D. morifolium and enabling breeding of new D. morifolium cultivars, we developed a set of molecular markers. We used pyrosequencing of an enriched microsatellite library by Roche 454 FLX+ platform, to isolate D. morifolium simple sequence repeats (SSRs). A total of 32,863 raw reads containing 2251 SSRs were obtained. To test the effectiveness of these SSR markers, we designed primers by randomly selecting 100 novel SSRs, and amplified them across 60 cultivars representing five different petal shape groups. Sixteen SSRs were polymorphic with the number of alleles ranging from 6 to 19, and their expected and observed heterozygosities ranging from 0.477 to 0.848, and 0.250 to 0.804, respectively. The polymorphism information content ranged from 0.459 to 0.854 and the inbreeding coefficient ranged from -0.119 to 0.759. An unweighted pair-group method arithmetic average analysis was performed to survey the phylogenetic relationships of these 60 cultivars and five clusters were identified. These markers can be used for investigating genetic relationships and identifying elite alleles through linkage and association analyses.

Isolation and characterization of microsatellite markers for Osmanthus fragrans (Oleaceae) using 454 sequencing technology.

Osmanthus fragrans (Oleaceae) is an evergreen shrub or small tree that grows in south China. In this study, Roche 454 FLX+ sequencing combined with the magnetic bead enrichment method was used to isolate microsatellite markers from the genome of O. fragrans. A total of 1471 microsatellites that contained enough flanking sequences for primer pair design were identified from 89,633 raw sequencing reads. One hundred primer pairs were randomly chosen to test primer amplification efficiency. Among these tested primer pairs, 20 yielded polymorphic amplification products across 16 individuals from the Albus, Luteus, and Aurantiacus groups. The number of alleles ranged from 2 to 6, with an average of 3.7. The observed heterozygosity ranged from 0 to 0.813, with an average of 0.460. Shannon's information index ranged from 0.463 to 1.707, with an average of 0.975. Six loci (Of 05, Of 06, Of 08, Of 12, Of 15, and Of 19) deviated significantly from Hardy-Weinberg equilibrium (P < 0.05), which was due to an excess of homozygotes or heterozygotes. Nine pairs of loci (Of 01 and Of 05; Of 04 and Of 05; Of 01 and Of 06; Of 04 and Of 12; Of 02 and Of 13; Of 04 and Of 13; Of 12 and Of 13; Of 04 and Of 19; Of 05 and Of 19) showed significant linkage disequilibrium, which indicated significant allelic association between the loci. This set of microsatellite markers will be valuable for molecular marker-assisted breeding in O. fragrans.

[2, 6-dimethoxy-1, 4-benzoquinone alleviates septic shock in mice by inhibiting NLRP3 inflammasome activation].

OBJECTIVE: To investigate the mechanism of 2, 6-dimethoxy-1, 4-benzoquinone (DMQ), an active ingredients in fermented wheat germ extract, for inhibiting NLRP3 inflammasome activation and alleviating septic shock in mice. METHODS: Cultured murine bone marrow-derived macrophages (BMDM) stimulated with lipopolysaccharide (LPS) were treated with DMQ, followed by treatment with Nigericin, ATP, and MSU for activating the canonical NLRP3 inflammasome; the noncanonical NLRP3 inflammasome was activated by intracellular transfection of LPS, and AIM2 inflammasome was activated using Poly A: T.In human monocytic THP-1 cells, the effect of Nigericin on inflammasome activation products was examined using Western blotting and ELISA.Co-immunoprecipitation was performed to explore the mechanism of DMQ-induced blocking of NLRP3 inflammasome activation.In a male C57BL/6J mouse model of LPS-induced septic shock treated with 20 and 40 mg/kg DMQ, the levels of IL-1ß and TNF-α in the serum and peritoneal lavage fluid were determined using ELISA, and the survival time of the mice within 36 h was observed. RESULTS: Treatment with DMQ effectively inhibited LPS-induced activation of canonical NLRP3 inflammasome in mouse BMDM and human THP-1 cells and also inhibited non-canonical NLRP3 inflammasome activation in mouse BMDM, but produced no significant effect on AIM2 inflammasome activation.DMQ significantly blocked the binding between ASC and NLRP3.In the mouse models of septic shock, DMQ treatment significantly reduced the levels of IL-1ß in the serum and peritoneal fluid and obviously prolonged survival time of the mice. CONCLUSION: DMQ can effectively block ASC-NLRP3 interaction to inhibit NLRP3 inflammasome activation and alleviate LPSinduced septic shock in mice.

Safety and efficacy of oral lopinavir/ritonavir in pediatric patients with coronavirus disease: a nationwide comparative analysis.

OBJECTIVE: Because of the limited treatment options available, oral lopinavir/ritonavir (LPR) was used for treating coronavirus disease (COVID-19) in pediatric patients. This study aimed to assess the efficacy and safety of LPR in COVID-19 pediatric patients with mild symptoms. PATIENTS AND METHODS: This retrospective multicenter analysis included hospitalized children with mild COVID-19 who received LPR at one of 13 hospitals in China from January 1, 2020, to June 1, 2020. Patients treated with LPR were matched with patients not treated with LPR (1:4) according to age, sex, and length of symptom onset and hospitalization. Descriptive statistics and non-parametric tests were applied to compare differences between groups. Kaplan-Meier probability curves and Cox regression models were used to analyze nasal swab turning negative time (recovery time) and hospital discharge days. RESULTS: In total, 23 patients treated with LPR were matched with 92 untreated controls. The median age of patients was 6 years, and 56.52% of them were male. All patients were discharged from the hospital after being cured. The treatment group had a longer nasal swab turning negative time (hazard ratio [HR] 5.33; 95% CI: 1.94-14.67; p = 0.001) than the control group. LPR treatment was also associated with a longer hospitalization time (HR 2.01; 95% CI: 1.24-3.29; p = 0.005). After adjusting for the influence of LPR treatment, adverse drug reaction events were associated with a longer nasopharyngeal swab negative time (HR 4.67; 95% CI 1.35-16.11; p = 0.015). CONCLUSIONS: For children with mild COVID-19, LPR is inferior to conventional treatment in reducing virus shedding time and hospitalization duration and is associated with increased adverse reactions.

Over-expression of DJ-1 attenuates effects of curcumin on colorectal cancer cell proliferation and apoptosis.

Since this article has been suspected of research misconduct and the corresponding authors did not respond to our request to prove originality of data and figures, "Over-expression of DJ-1 attenuates effects of curcumin on colorectal cancer cell proliferation and apoptosis, by H. Shang, T. Wang, F. Shang, M. Li, Y. Luo, K.-M. Huang, published in Eur Rev Med Pharmacol Sci 2019; 23 (7): 3080-3087-DOI: 10.26355/eurrev_201904_17591-PMID: 31002157" has been withdrawn. The Publisher apologizes for any inconvenience this may cause. https://www.europeanreview.org/article/17591.

LncRNA NEAT1 promotes the progression of sepsis-induced myocardial cell injury by sponging miR-144-3p.

OBJECTIVE: Sepsis is a systemic inflammatory response that can lead to the dysfunction of many organs, including the cardiac one. Long noncoding RNAs (lncRNAs) have been shown to be involved in multiple organ injuries induced by sepsis. However, the regulatory effect of nuclear enriched abundant transcript 1 (NEAT1) on sepsis-induced myocardial injury remains to be explored. MATERIALS AND METHODS: The sepsis models of myocardial cell injury were constructed using lipopolysaccharide (LPS). Cell counting kit-8 (CCK-8) assay was used to detect cell viability. Flow cytometry was performed to assess cell apoptosis. Moreover, the levels of apoptosis-related and nuclear factor-kappa B (NF-κB) signaling pathway-related proteins were evaluated by Western blot (WB) analysis. Besides, the contents of inflammatory cytokines were tested by enzyme-linked immunosorbent assay (ELISA). The expression levels of NEAT1 and microRNA-144-3p (miR-144-3p) were determined by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). In addition, Dual-Luciferase reporter and RNA immunoprecipitation (RIP) assays were used to verify the interaction between NEAT1 and miR-144-3p. RESULTS: LPS could induce myocardial cell injury to construct sepsis models. NEAT1 was upregulated in LPS-treated myocardial cells, and its knockdown promoted viability, suppressed apoptosis, and relieved inflammatory response in LPS-induced myocardial cell injury. MiR-144-3p was downregulated in LPS-treated myocardial cells, and the effect of its overexpression on LPS-induced myocardial cell injury was similar to the effect of NEAT1 knockdown. Besides, miR-144-3p could be sponged by NEAT1, and its inhibitor could reverse the effect of NEAT1 knockdown on LPS-induced myocardial cell injury. Moreover, NEAT1 and miR-144-3p could regulate the activity of NF-κB signaling pathway. CONCLUSIONS: LncRNA NEAT1 could interact with miR-144-3p to regulate sepsis-induced myocardial cell injury through the NF-κB signaling pathway, which might provide a new theoretical basis for the study on the effect of sepsis treatment.

Analysis of expressed sequence tags from Chaetomium cupreum grown under conditions associated with mycoparasitism.

AIMS: To elucidate the molecular mechanisms associated with mycoparasitism from Chaetomium cupreum, an effective biocontrol agent with ability against plant pathogenic fungi. METHODS AND RESULTS: One cDNA library was constructed from conditions predicted to resemble mycoparasitic process. A total of 1876 ESTs were generated and assembled into 1035 unigenes. BlastX search revealed that 585 unigenes had similarities with sequences available from public databases. Based on the ESTs abundance, MFS monosaccharide transporter was found as the gene expressed at the highest level. A KEGG analysis allowed mapping of 60 metabolic pathways well represented by the glycolysis/gluconeogenesis, D-arginine and ornithine metabolism, and tryptophan metabolism. The genes related to mycoparasitism were detected. CONCLUSIONS: The results revealed that the cell walls of the fungal pathogen can simulate some aspects of the mycoparasitic interaction between C. cupreum and its targets. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first report to study genes expression under conditions associated with the mycoparasitic process. The findings contribute to elucidate the molecular mechanisms involved in mycoparasitism and will help to advance our efforts in developing novel strategies for biocontrol of plant fungal diseases.

[Application of mathematical function model in morphological description and classification of bone defect in cleft palate cases].

Objective: To establish the functional models based on various shapes of bone defects in isolated cleft palate patients and to classify the bone defects of the cleft palate cases using different functional curves. Methods: Tracking back from January 2018 to December 2018, 143 patients with cleft palate (Veau Ⅰ & Ⅱ) treated in Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology, were included (age of 7 months to 25 years, average age 1.6 years, median age 1.0 year, the male to female ratio was 0.57∶1).The pre-operative (CT) data sets were reconstructed into a three dimensional model to produce a direct image of the cleft palate. According to the shapes of the bone defect, cleft palate cases were divided into three types, i.e."" shape, inverted "V" shape and inverted "U" shape, and then the cases were assessed and reviewed by five examiners independently. Using Microsoft Excel software, the curves of the bone defect were placed in the coordinate system for mathematical modeling, including exponential function (y=ae(bx)), linear function (y=ax+b) and logarithm function (y=alnx+b). The function of the maximum fit R(2) value was used as the final fit curve. Statistical analysis was performed in four aspects: ① The reliability and feasibility of the curve fitting of the functions; ② The calculation of the composition ratio of the types of bone defect; ③Analyzing the correspondence between the subjective judgment results and fitting function curves; ④ The R(2) values of three types of functional curves homologous to different morphological types, and the data were tested by variance analysis and P values were shown. Results: Among the 143 patients with cleft palate, the "" shaped defect accounted for 18% (26/143), the inverted "V" shaped defect accounted for 31% (44/143), and the inverted "U" shaped defect accounted for 51% (73/143). The coincidence rate of the "" shaped defect with the exponential function (y=ae(bx)) was 96%, the coincidence rate of the inverted "V" shaped defect with the linear function (y=ax+b) was 82%, and the coincidence rate of the inverted "U" shaped defect with the logarithmic function (y=alnx+b) was 93%. The differences in R(2) values amongst the three groups were statistically significant (P<0.05). Conclusions: The shapes of bone defects of the incomplete cleft palate can be described by functional curve models which include exponential, linear and logarithmic functions and can be used to classify and lay the foundation for digital classification of cleft lip and palate cases.

Up­regulation of lncRNA PXN-AS1-L is associated with unfavorable prognosis in patients suffering from glioma.

OBJECTIVE: Growing evidence has proved that long noncoding RNAs (lncRNAs) act as novel regulators in the progression of various tumors by modulating miRNAs and tumor-related genes. However, the potential function of lncRNA PXN-AS1-L (PXN-AS1-L) in glioma remains unknown. Hence, we aimed to determine whether PXN-AS1-L was dysregulated in glioma and further preliminarily explored its prognostic value in glioma patients. PATIENTS AND METHODS: RT-PCR was used for the assessment of PXN-AS1-L levels in glioma tissue and matched normal tissues from our hospital. Chi-square test was applied to explore the possible association between PXN-AS1-L expressions and clinical factors. Kaplan-Meier survival analysis was carried out to determine the influence of PXN-AS1-L expressions on the survival rate of glioma patients. Survival data were further evaluated through univariate and multivariate analyses. RESULTS: PXN-AS1-L levels were differentially upregulated in glioma specimens compared with paired non-tumor specimens. Higher levels of PXN-AS1-L in glioma were observed to be positively associated with WHO grade (p = 0.019), KPS (p = 0.008)and tumor recurrence (p = 0.019). Survival assays revealed that glioma patients with higher PXN-AS1-L expressions had worse overall survival rates. In multivariate analysis, upregulation of PXN-AS1-L expressions (Risk ratio = 2.663, 1.218-4.532, p = 0.014) in glioma tissues was confirmed to be an independent prognostic factor of overall survival in patients. CONCLUSIONS: We firstly suggested that PXN-AS1-L was overexpressed in glioma, and could be used as a novel marker of unfavorable outcome in glioma patients.

MiR-491 functions as a tumor suppressor through Wnt3a/ß-catenin signaling in the development of glioma.

OBJECTIVE: Glioma is the most frequent brain tumor that has high invasion and usually disperses to the whole brain through blood and basement membranes. MicroRNA-491 (miR-491) has been reported to have low expression and act as a tumor suppressor in several cancers. The Wnt/ß-catenin signaling is a classic signaling pathway that participated in several biological processes. Our purpose was to detect the molecular mechanism of miR-491 in regulating the growth and metastasis of glioma. MATERIALS AND METHODS: Real Time-quantitative Polymerase Chain Reaction (RT-qPCR) was applied to calculate the mRNA level of miR-491 and target gene. The protein expression of special genes was assessed by Western blot. The proliferation and invasive abilities were measured by the Cell Counting Kit-8 (CCK-8) and transwell assays. The Kaplan-Meier method was conducted to evaluate the association between the expressions of miR-491 with the overall survival of glioma patients. RESULTS: We discovered that miR-491 was lowly expressed in glioma and downregulation of miR-491 predicted poor outcome of glioma patients. Similarly, a high expression of miR-491 suppressed the growth and metastasis in glioma cell line LN229. MiR-491 high expression inhibited the growth of glioma in a mouse xenograft model. Moreover, Wnt3a was a target gene of miR-491 and miR-491 mediated the invasion-mediated epithelial-mesenchymal transition (EMT) by regulating the expression of Wnt3a. Additionally, miR-491 regulated the proliferation through the Wnt/ß-Catenin pathway by targeting Wnt3a. CONCLUSIONS: MiR-491 overexpression inhibited the proliferation through the Wnt3a/ß-catenin pathway and invasion-mediated EMT in glioma. The newly identified miR-491/Wnt3a/ß-catenin axis provides novel insight into the pathogenesis of glioma.

Over-expression of DJ-1 attenuates effects of curcumin on colorectal cancer cell proliferation and apoptosis.

OBJECTIVE: The phosphatase and tensin homologue deleted on chromosome ten (PTEN) acts as a tumor suppressor gene by inhibiting the phosphatidylinositol 3-kinase/protein kinase B (PI3K/AKT) signaling pathway. DJ-1, a negative regulator of PTEN, is associated with the pathogenesis of a variety of tumors. Curcumin (Cur) is a phenolic compound that is extracted from various plant rhizomes with various anti-tumor pharmacological effects. This study aimed to investigate the effects of Cur on proliferation and apoptosis of colorectal cancer cells. MATERIALS AND METHODS: Human normal colorectal epithelial cell line (NCM460) and colorectal cancer cell line (SW480 and SW620) were cultured in vitro. Real-time quantitative PCR (RT-PCR) and western blot were used to detect DJ-1 and PTEN mRNA and protein, respectively. Cell apoptosis was determined with flow cytometry. SW480 cells were divided into control, 20 µM Cur treatment group, Cur+pcDNA3.1-Blank group and Cur+pcDNA3.1-DJ-1 group. Cell proliferation activity was evaluated with EdU staining. RESULTS: Comparing with NCM460 cells, DJ-1 was significantly increased, while PTEN was significantly declined in SW480 and SW620 cells (p<0.05). Cur treatment significantly inhibited SW480 and SW620 cell proliferation and significantly induced apoptosis compared to control group (p<0.05) but showed no significant effects on NCM460 cells. Cur down-regulated DJ-1 level and enhanced PTEN expressions in SW480 cells with dose dependence. The pcDNA3.1-DJ-1 transfection significantly declined PTEN expression, enhanced p-AKT levels, reduced cell apoptosis, and strengthened cell proliferation in SW480 cells treated by Cur (p<0.05). CONCLUSIONS: Cur can inhibit colorectal cancer cell proliferation and promote apoptosis by down-regulating DJ-1 expression to regulate the activity of PTEN/PI3K/AKT signaling pathway.

Expression of K6W-ubiquitin in lens epithelial cells leads to upregulation of a broad spectrum of molecular chaperones.

PURPOSE: Accumulation and precipitation of abnormal proteins are associated with many age-related diseases. The ubiquitin-proteasome pathway (UPP) is one of the protein quality control mechanisms that selectively degrade damaged or obsolete proteins. The other arm of the protein quality control mechanism is molecular chaperones, which bind to and help refold unfolded or misfolded proteins. We previously showed that the molecular chaperones and the UPP work in a competitive manner in eliminating the denatured proteins. To further investigate the interaction between the two protein quality control mechanisms, we determined the effects of the impairment of the UPP on the expression of molecular chaperones in human lens epithelial cells (HLEC). METHODS: K6W-ubiquitin, a dominant negative inhibitor of the UPP, was expressed in confluent HLEC via an adenoviral vector. The mRNA levels of cytoplasmic and endoplasmic reticulum (ER) chaperones were determined by real-time reverse transcription polymerase chain reaction (RT-PCR). Protein levels for these chaperones were determined by western blotting. RESULTS: Expression of K6W-ubiquitin in HLEC increased the expression of a broad spectrum of molecular chaperones. Among the heat-shock proteins, mRNA for alphaB-crystallin, Hsp70, and Hsp90 increased 27 fold, 21 fold, and twofold, respectively, in response to K6W-ubiquitin expression. Among the ER chaperones and ER stress related factors, mRNA levels of protein disulfide isomerase, Grp75, Grp78, Grp94, and the CAAT/enhancer binding protein homologous protein (CHOP) increased from 1.7 fold to 3.7 fold. The mRNA for Hsp60 also increased 1.6 fold in response to the expression of K6W-ubiquitin. The expression pattern of these chaperones in response to the expression of K6W ubiquitin is similar to that obtained when cells were treated with proteasome inhibitors or heat-shock. CONCLUSIONS: It appears that the upregulation of these chaperones is related to the elevated levels of abnormal proteins in the cells. These findings support our hypothesis that the molecular chaperones and the UPP may back each other up in the process of protein quality control. The upregulation of molecular chaperones in response to the expression of a dominant negative ubiquitin may compensate for the impairment of the UPP in the degradation of abnormal proteins.

Increased HSPG2 expression independently predicts poor survival in patients with oligoastrocytoma and oligodendroglioma.

OBJECTIVE: Perlecan, which is also called heparan sulfate proteoglycan 2 (HSPG2), is a protein encoded by the HSPG2 gene that maps to 1p36.12 in the human genome. In this study, we assessed the independent prognostic value of HSPG2 in terms of overall survival (OS) and recurrence-free survival (RFS) in patients with LGG. PATIENTS AND METHODS: A retrospective study was conducted by using data in the Cancer Genome Atlas-Low Grade Glioma (TCGA-LGG). RESULTS: Increased HSPG2 expression was an independent prognostic indicator of poor OS in oligoastrocytoma (HR: 1.644, 95% CI: 1.116-2.423, p = 0.012) and in oligodendroglioma (HR: 1.459, 95% CI: 1.138-1.871, p = 0.003). In addition, increased HSPG2 expression independently predicted poor RFS in oligodendroglioma (HR: 1.402, 95% CI: 1.110-1.770, p = 0.005). Furthermore, we observed that high HSPG2 expression was associated with significantly shorter OS and RFS in oligodendroglioma, no matter the patients received radiotherapy or not. Using copy number alterations (CNAs) and DNA methylation data in TCGA-LGG, we found that DNA copy deletion was generally associated with decreased HSPG2 expression. Regression analysis suggested a weak negative correlation between HSPG2 expression and HSPG2 DNA methylation (Pearson's r = -0.388). CONCLUSIONS: Increased HSPG2 expression could independently predict poor OS in oligoastrocytoma and oligodendroglioma and also independently predicted poor RFS in oligodendroglioma. Its expression is modulated by both DNA copy number and DNA methylation in oligodendroglioma.

Glutathiolation Triggers Proteins for Degradation by the Ubiquitin- Proteasome Pathway.

BACKGROUND: Glutathione is a small antioxidant peptide in cells and it plays an important role in maintaining a reducing intracellular environment. Glutathione is also involved in the dynamic regulation of specific protein functions by reversible glutathiolation of certain proteins in response to oxidative stress. OBJECTIVE: The purpose of this work is to mechanistically investigate the effects of glutathiolation on the susceptibility of proteins to degradation by the ubiquitinproteasome pathway (UPP). METHODS AND RESULTS: The data show that γC-crystallin and carbonic anhydrase III were barely degraded by the UPP without modifications, but both were rapidly degraded by the UPP after glutathiolation. Modifications of sulfhydryls by other thiol-modification reagents, such as iodoacetamide, also increased the degradation of γC-crystallin, but not as effectively as glutathiolation. Biophysical analysis showed that glutathiolation caused reversible conformational changes of these proteins, including a significant increase in protein surface hydrophobicity and a decrease in thermal stability. The modified protein regained its native conformation and its resistance to degradation upon removal of the glutathione moiety. A cataract-causing T5P mutant γC-crystallin shares many biophysical characteristics as glutathiolated γC-crystallin, including increased surface hydrophobicity and decreased thermal stability. T5P mutant γC-crystallin was also rapidly degraded. Comparison of the conformational changes and the susceptibility to degradation of glutathiolated γC-crystallin with other forms of modified γC-crystallin suggests that the glutathiolation-induced exposure of hydrophobic patches, rather than the modification per se, serves as the signal for degradation by the UPP. Consistent with this hypothesis, masking the surface hydrophobicity of glutathiolated and T5P mutant γC-crystallins significantly reduced their susceptibility to degradation by the UPP. CONCLUSION: This work demonstrates that glutathiolation is a novel mechanism for the UPP to recognize substrates in response to oxidative stress.

Serum Carotenoids and Risks of Diabetes and Diabetic Retinopathy in a Chinese Population Sample.

OBJECTIVE: Diabetes mellitus (DM) and diabetic retinopathy (DR) are associated with oxidative stress and carotenoids have antioxidant properties. This study aimed to test the relationship between serum carotenoid concentrations and the risk for DM and DR. METHODS: This is a cross-sectional study of the Chinese urban population. A total of 747 subjects, consisting of 272 DR patients, 190 diabetic patients without retinopathy, and 285 non-diabetes mellitus healthy controls, were recruited to this study. Demographic and lifestyle characteristics were ascertained by questionnaire. General physical and ophthalmic examinations were completed for all participants. Serum carotenoids were measured by high-performance liquid chromatography (HPLC). The associations of serum carotenoids with DM and DR were assessed by logistic regression with adjustment of known risk factors. The correlation analyses of serum carotenoids with the candidate influence factors were assessed using the single variable linear regression. RESULTS: Both pro-vitamin A (PVA) carotenoids and non-PVA carotenoids in the serum were measured and compared between different groups. Levels of α-carotene were significantly lower in DR patients and ß-carotene were significantly lower in DM patients as compared to non DM healthy control group. In contrast, levels of ß-cryptoxanthin, lycopene, lutein and zeaxanthin were comparable among different groups. After adjusting for confounding factors, ß-carotene concentration was associated with reduced risk for DM (OR (95%CI): 0.56 (0.34, 0.91), P=0.02) and α-carotene was associated with reduced risk for DR in non-smokers (OR (95%CI): 0.41 (0.17, 0.99), P=0.048). No significant association was found between hemoglobin A1c and any carotenoids (P>0.05). Significantly associations with serum carotenoids were found in age, sex, BMI, smoking, and exercise (P<0.05). CONCLUSION: Serum ß-carotene may have a protective effect on DM and α-carotene may be a protective factor for DR in non-smokers.