A Double-Edged Sword: Complement Component 3 in Toxoplasma gondii Infection.

Sprague Dawley rats and Kunming (KM) mice are artificially infected with type II Toxoplasma gondii strain Prugniaud (Pru) to generate toxoplasmosis, which is a fatal disease mediated by T. gondii invasion of the central nervous system (CNS) by unknown mechanisms. The aim is to explore the mechanism of differential susceptibility of mice and rats to T. gondii infection. Therefore, a strategy of isobaric tags for relative and absolute quantitation (iTRAQ) is established to identify differentially expressed proteins (DEPs) in the rats' and the mice's brains compared to the healthy groups. In KM mice, which is susceptible to T. gondii infection, complement component 3 (C3) is upregulated and the tight junction (TJ) pathway shows a disorder. It is presumed that T. gondii-stimulated C3 disrupts the TJ of the blood-brain barrier in the CNS. This effect allows more T. gondii passing to the brain through the intercellular space.

Effect of concentration, temperature, and time on the stability of hepatitis C virus nucleic acid in serum.

To explore the influence of storage temperature and time on the stability of different concentrations of hepatitis C virus nucleic acid (HCV RNA) samples and to provide data reference for laboratory quality control. Serum samples of 10 patients with HCV RNA detection quantitation of 106-108 IU/mL were collected. The samples of each patient were diluted into three concentrations: high, medium, and low. Then the samples of each concentration were divided into 21, which were divided into three groups according to the storage conditions of -20°C, 4°C, and 25°C, with seven samples in each group. The samples were selected from each group for quantitative detection of HCV RNA on day 0, day 1, day 3, day 5, day 7, day 14, and day 30. The results of each concentration and storage temperature sample remained stable within 5 days. Based on the mixed-effect linear model, the main effects of temperature, time, and concentration were statistically significant (P < 0.01). There was an interaction effect between concentration and time (P = 0.0448), and there was also an interaction effect between temperature and time (P < 0.01). There was no interaction effect between concentration and temperature (P = 0.11) or between concentration, temperature, and time (P = 0.90). The results of serum samples with different concentrations of the HCV RNA remained stable within 5 days. The lower the initial concentration of HCV RNA serum sample, the worse the stability; the higher the storage temperature, the worse the stability. If conditions permit, the laboratory should store such samples at -20°C. IMPORTANCE: Previously, there were few reports about the influence of different concentrations of sample nucleic acid on the stability of samples at various temperatures and times in various literatures. Therefore, it is necessary to analyze the influence of concentration factors on the stability of samples and test results at different storage times and temperatures. This study took the concentration of hepatitis C virus nucleic acid as the research object to further understand the stability of hepatitis C virus nucleic acid test samples under various storage conditions, to provide data reference for the treatment of hepatitis C virus nucleic acid and RNA test samples before clinical laboratory test, and provide guidance and help for the improvement of laboratory quality control.

Caffeic acid phenethyl ester suppresses EGFR/FAK/Akt signaling, migration, and tumor growth of prostate cancer cells.

BACKGROUND: Epidermal growth factor receptor (EGFR) is upregulated in prostate cancer (PCa). However, suppression of EGFR did not improve the patient outcome, possibly due to the activation of PI3K/Akt signaling in PCa. Compounds able to suppress both PI3K/Akt and EGFR signaling may be effective for treating advanced PCa. PURPOSE: We examined if caffeic acid phenethyl ester (CAPE) simultaneously suppresses the EGFR and Akt signaling, migration and tumor growth in PCa cells. METHODS: Wound healing assay, transwell migration assay and xenograft mice model were used to determine the effects of CAPE on migration and proliferation of PCa cells. Western blot, immunoprecipitation, and immunohistochemistry staining were performed to determine the effects of CAPE on EGFR and Akt signaling. RESULTS: CAPE treatment decreased the gene expression of HRAS, RAF1, AKT2, GSK3A, and EGF and the protein expression of phospho-EGFR (Y845, Y1069, Y1148, Y1173), phospho-FAK, Akt, and ERK1/2 in PCa cells. CAPE treatment inhibited the EGF-induced migration of PCa cells. Combined treatment of CAPE with EGFR inhibitor gefitinib showed additive inhibition on migration and proliferation of PCa cells. Injection of CAPE (15 mg/kg/3 days) for 14 days suppressed the tumor growth of prostate xenografts in nude mice as well as suppressed the levels of Ki67, phospho-EGFR Y845, MMP-9, phospho-Akt S473, phospho-Akt T308, Ras, and Raf-1 in prostate xenografts. CONCLUSIONS: Our study suggested that CAPE can simultaneously suppress the EGFR and Akt signaling in PCa cells and is a potential therapeutic agent for advanced PCa.

Aspalathus linearis suppresses cell survival and proliferation of enzalutamide-resistant prostate cancer cells via inhibition of c-Myc and stability of androgen receptor.

Enzalutamide, a nonsteroidal antiandrogen, significantly prolonged the survival of patients with metastatic castration-resistant prostate cancer (CRPC). However, patients receiving enzalutamide frequently develop drug resistance. Rooibos (Aspalathus linearis) is a shrub-like leguminous fynbos plant endemic to the Cedarberg Mountains area in South Africa. We evaluated the possibility of using a pharmaceutical-grade green rooibos extract (GRT, containing 12.78% aspalathin) to suppress the proliferation and survival of enzalutamide-resistant prostate cancer (PCa) cells. Treatment with GRT dose-dependently suppressed the proliferation, survival, and colony formation of enzalutamide-resistant C4-2 MDV3100r cells and PC-3 cells. Non-cancerous human cells were more resistant to GRT treatment. GRT suppressed the expression of proteins involved in phosphoinositide 3-kinase (PI3K)-Akt signaling, androgen receptor (AR), phospho-AR (Ser81), cyclin-dependent kinase 1 (Cdk1), c-Myc and Bcl-2 but increased the expression of apoptotic proteins. Overexpression of c-Myc antagonized the suppressive effects of GRT, while knockdown of c-Myc increased the sensitivity of PCa cells to GRT treatment. Expression level of c-Myc correlated to resistance of PCa cells to GRT treatment. Additionally, immunofluorescence microscopy demonstrated that GRT reduced the abundance of AR proteins both in nucleus and cytoplasm. Treatment with cycloheximide revealed that GRT reduced the stability of AR. GRT suppressed protein expression of AR and AR's downstream target prostate specific antigen (PSA) in C4-2 MDV3100r cells. Interestingly, we observed that AR proteins accumulate in nucleus and PSA expression is activated in the AR-positive enzalutamide-resistant PCa cells even in the absence of androgen. Our results suggested that GRT treatment suppressed the cell proliferation and survival of enzalutamide-resistant PCa cells via inhibition of c-Myc, induction of apoptosis, as well as the suppression of expression, signaling and stability of AR. GRT is a potential adjuvant therapeutic agent for enzalutamide-resistant PCa.

A Transcriptome Analysis: Various Reasons of Adverse Pregnancy Outcomes Caused by Acute Toxoplasma gondii Infection.

BACKGROUND: Toxoplasma gondii (T. gondii) is an obligate intracellular parasite, which can affect the pregnancy outcomes in infected females by damaging the uterus, and the intrauterine environment as well as and the hypothalamus resulting in hormonal imbalance. However, the molecular mechanisms underlying the parasite-induced poor pregnancy outcomes and the key genes regulating these mechanisms remain unclear. Therefore, this study aimed to analyze the gene expression in the mouse's uterus following experimentally-induced acute infection with T. gondii RH strain. Three groups of female mice were intraperitoneally injected with tachyzoites as follow; 3 days before pregnancy (FBD6), after pregnancy (FAD6), and after implantation (FID8) as the experimental groups. Another corresponding three groups served as control, were injected with normal saline at the same time. Transcriptome analysis of the total RNA extracted from both infected and non-infected mouse uterus samples was performed using RNA sequencing (RNA-Seq). RESULTS: The three experimental groups (FBD6, FAD6, and FID8) had a total of 4,561, 2,345, and 2,997 differentially expressed genes (DEGs) compared to the controls. The significantly upregulated and downregulated DEGs were 2,571 and 1,990 genes in FBD6, 1,042 and 1,303 genes in FAD6 and 1,162 and 1,835 genes in FID8 group, respectively. The analysis of GO annotation, and KEGG pathway showed that DEGs were mainly involved in anatomical structure development, transport, cell differentiation, embryo development, hormone biosynthetic process, signal transduction, immune system process, phagosome, pathways in cancer, and cytokine-cytokine receptor interaction pathways. CONCLUSION: T. gondii infection can induce global transcriptomic changes in the uterus that may cause pregnancy hypertension, destruct the intrauterine environment, and hinder the normal development of placenta and embryo. Our results may help to understand the molecular mechanisms of the acute T. gondii infection, which could promote the development of new therapeutics or prophylactics for toxoplasmosis in pregnancy.

Transcriptomic analysis of reproductive damage in the epididymis of male Kunming mice induced by chronic infection of Toxoplasma gondii PRU strain.

BACKGROUND: Some researchers have reported that Toxoplasma gondii can cause serious reproductive impairment in male animals. Specifically, T. gondii destroy the quality of sperm in the epididymis, which affects their sexual ability. However, among such studies, none have investigated the male reproductive transcriptome. Therefore, to investigate the relationship between T. gondii and sperm maturation, we infected mice with T. gondii prugniaud (PRU) strain and performed transcriptome sequencing of the epididymis. RESULTS: Compared with the control group, 431 upregulated and 229 downregulated differentially expressed genes (DEGs) were found (P-value < 0.05, false discovery rate (FDR) < 0.05 and |log2 (fold change)| ≥ 1). According to results of a bioinformatics analysis, Gene Ontology (GO) function is divided into three categories: cellular component, molecular function and biological process. Upon performing GO analysis, we found that some DEGs correlated with an integral part of membrane, protein complex, cell surface, ATP binding, immune system process, signal transduction and metabolic process which are responsible for the epididymal injury. DEGs were mapped to 101 unique KEGG pathways. Pathways such as cytokine-cytokine receptor interaction, glycolysis/gluconeogenesis and apoptosis are closely related to sperm quality. Moreover, Tnfsf10 and spata18 can damage the mitochondria in sperm, which decreases sperm motility and morphology. CONCLUSIONS: We sequenced the reproductive system of male mice chronically infected with T. gondii, which provides a new direction for research into male sterility caused by Toxoplasma infection. This work provides valuable information and a comprehensive database for future studies of the interaction between T. gondii infection and the male reproductive system.