Plasmodium manipulates the expression of host long non-coding RNA during red blood cell intracellular infection.

BACKGROUND: Parasites interact with their host through "direct" and/or "indirect" mechanisms. Plasmodium, for example, either mediates direct physical interactions with host factors or triggers the immune system of the host indirectly, leading to changes in infectious outcomes. Long non-coding RNAs (lncRNAs) participate in regulating biological processes, especially host-pathogen interactions. However, research on the role of host lncRNAs during Plasmodium infection is limited. METHODS: A RNA sequencing method (RNA-seq) was used to confirm the differential expression profiles of lncRNAs in Plasmodium yeolii 17XL (P.y17XL)-infected BALB/c mice. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses were performed to elucidate the potential functions of Plasmodium-induced genes. Subsequently, the effect of specific lncRNAs on the modulation of immune-related signaling pathways in malaria was determined by fluorescence-activated cell sorting, western blot and enzyme-linked immunosorbent assay. RESULTS: The data showed that in P.y17XL-infected BALB/c mice, Plasmodium upregulated the expression of 132 lncRNAs and downregulated the expression of 159 lncRNAs. Differentially expressed lncRNAs clearly associated with malaria infection were annotated, including four novel dominant lncRNAs: ENMSUSG00000111521.1, XLOC_038009, XLOC_058629 and XLOC_065676. GO and KEGG pathway analyses demonstrated that these four differentially expressed lncRNAs were associated with co-localized/co-expressed protein-coding genes that were totally enriched in malaria and with the transforming growth factor beta (TGF-ß) signaling pathway. Using the models of P.y17XL-infected BALB/c mice, data certified that the level of TGF-ß production and activation of TGF-ß/Smad2/3 signaling pathway were obviously changed in malaria infection. CONCLUSIONS: These differentially expressed immune-related genes were deemed to have a role in the process of Plasmodium infection in the host via dendritic/T regulatory cells and the TGF-ß/Smad2/3 signaling pathway. The results of the present study confirmed that Plasmodium infection-induced lncRNA expression is a novel mechanism used by Plasmodium parasites to modify host immune signaling. These results further enhance current understanding of the interaction between Plasmodium and host cells.

B-Myb accelerates colorectal cancer progression through reciprocal feed-forward transactivation of E2F2.

B-Myb is an important transcription factor that plays a critical role in gene expression regulation and tumorigenesis. However, its functional implication in colorectal cancer remains elusive. In this study, we found that B-Myb was significantly upregulated at both mRNA and protein levels in colorectal cancer samples compared to non-tumor counterparts. B-Myb overexpression accelerated cell proliferation, cell cycle progression and cell motility in colorectal cancer cells, and promoted tumor growth in orthotopic nude mouse models in vivo. In contrast, B-Myb depletion inhibited these malignant phenotypes. Mechanistic investigations revealed that E2F2 was a novel transcriptional target of B-Myb and is essential to B-Myb-induced malignant phenotypes. Notably, B-Myb and E2F2 exhibited positive expression correlation, and interacted with each other in colorectal cancer cells. In addition to their autoregulatory mechanisms, B-Myb and E2F2 can also directly transactivate each other, thus constituting consolidated reciprocal feed-forward transactivation loops. Moreover, both B-Myb and E2F2 are required for the activation of ERK and AKT signaling pathways in colorectal cancer cells. Taken together, our data clarified a critical role for B-Myb in colorectal cancer and unraveled an exquisite mutual collaboration and reciprocal cross regulation between B-Myb and E2F2 that contribute to the malignant progression of human colorectal cancer.

Association between B-Myb proto-oncogene and the development of malignant tumors.

B-Myb is a critical transcription factor in regulating cell cycle. Dysregulated expression of B-Myb promotes tumor formation and development. B-Myb is a proto-oncogene ubiquitously expressed in proliferating cells, which maintains normal cell cycle progression. It participates in cell apoptosis, tumorigenesis and aging. In addition, B-Myb is overexpressed in several malignant tumors, including breast cancer, lung cancer and hepatocellular carcinoma, and is associated with tumor development. B-Myb expression is also associated with the prognosis of patients with malignant tumors. Both microRNAs and E2F family of transcription factors (E2Fs) contribute to the function of B-Myb. The present review highlights the association between B-Myb and malignant tumors, and offers a theoretical reference for the diagnosis and treatment of malignant tumors.

Gut Microbiota Dysbiosis Drives the Development of Colorectal Cancer.

BACKGROUND: The gut microbiota is a diverse community of microbes that maintain the stability of the intestinal environment. Dysbiosis of the gut microbiota has been linked to gastrointestinal diseases, such as colorectal cancer (CRC) - a leading cause of death for cancer patients. SUMMARY: Candidate pathogens have been identified using bacterial culture and high-throughput sequencing techniques. Currently, there is evidence to show that specific intestinal microbes drive CRC development and progression, yet their pathogenic mechanisms are still unclear. Key Messages: In this review, we describe the known healthy gut microbiota and its changes in CRC. We especially focus on exploring the pathogenic mechanisms of gut microbiota dysbiosis in CRC. This is crucial for explaining how gut microbiota dysbiosis drives the process of colorectal carcinogenesis and tumor progression. Evaluation of changes in the gut microbiota during CRC development and progression offers a new strategy for the diagnosis and treatment of this disease.

Gut-Brain-Skin Axis in Psoriasis: A Review.

INTRODUCTION: Psoriasis is a common skin disease, with chronic inflammation and a complex etiology. It has long been recognized that chronic skin conditions and mental health disorders are often co-morbid. Thus, the concept of the gut-brain-skin axis emphasized in mental health disorders may also regulate the health of skin. RESULTS: The gut microbiota has been found to be the bridge between the immune system and nervous system. By leveraging clinical cases and animal models of psoriasis, an important communication pathway has been identified along the gut-brain-skin axis that is associated with the modulation of neurotransmitters from the microbiota. Furthermore, mammalian neurotransmitters, including dopamine, serotonin, or γ-aminobutyric acid (GABA), can be produced and/or consumed by several types of bacteria. Other studies suggest that manipulating these neurotransmitters by bacteria may have an effect on host physiology, and the levels of neurotransmitter can be altered by microbiota-based interventions. CONCLUSIONS: Nonetheless, it is unknown whether or not the manipulation of neurotransmitter levels by bacteria can affect the occurrence and development of psoriasis. Notably, preliminary experiments found that oral consumption of probiotics improves the clinical symptoms in patients with psoriasis, perhaps correlated with the gut microbiome-mediated crosstalk between the immune system and the nervous system by secreting neurotransmitters in psoriasis. In this review, the communication along the gut-brain-skin axis is discussed.

Role of homocysteine in the development and progression of Parkinson's disease.

Homocysteine is an essential intermediate product of biochemical reactions that is present in various tissues of the human body. Homocysteine may be associated with the development and progression of Parkinson's disease. Plasma homocysteine levels in patients with Parkinson's disease are elevated compared to those of healthy individuals. High homocysteine drives PD development and progression while aggregating the clinical symptoms of PD patients. The relationship between PD and homocysteine involves multiple pathways, including nerve cell apoptosis, oxidative stress, and DNA damage. This is crucial for explaining how high homocysteine drives the PD procession. Elevated homocysteine level during PD development and progression offers a new strategy for the diagnosis and treatment of this disease.

Human umbilical cord-derived mesenchymal stem cells ameliorate insulin resistance via PTEN-mediated crosstalk between the PI3K/Akt and Erk/MAPKs signaling pathways in the skeletal muscles of db/db mice.

BACKGROUND: Globally, 1 in 11 adults have diabetes mellitus, and 90% of the cases are type 2 diabetes mellitus. Insulin resistance is a central defect in type 2 diabetes mellitus, and although multiple drugs have been developed to ameliorate insulin resistance, the limitations and accompanying side effects cannot be ignored. Thus, more effective methods are required to improve insulin resistance. METHODS: In the current study, db/m and db/db mice were injected with human umbilical cord-derived mesenchymal stem cells (HUC-MSCs) via tail vein injection, intraperitoneal injection, and skeletal muscle injection. Body weight, fasting blood glucose, and the survival rates were monitored. Furthermore, the anti-insulin resistance effects and potential mechanisms of transplanted HUC-MSCs were investigated in db/db mice in vivo. RESULTS: The results showed that HUC-MSC transplantation by skeletal muscle injection was safer compared with tail vein injection and intraperitoneal injection, and the survival rate reached 100% in the skeletal muscle injection transplanted mice. HUC-MSCs can stabilize localization and differentiation in skeletal muscle tissue and significantly ameliorate insulin resistance. Potential regulatory mechanisms are associated with downregulation of inflammation, regulating the balance between PI3K/Akt and ERK/MAPK signaling pathway via PTEN, but was not associated with the IGF-1/IGF-1R signaling pathway. CONCLUSIONS: These results suggest HUC-MSC transplantation may be a novel therapeutic direction to prevent insulin resistance and increase insulin sensitivity, and skeletal muscle injection was the safest and most effective way.

Kidney-targeted baicalin-lysozyme conjugate ameliorates renal fibrosis in rats with diabetic nephropathy induced by streptozotocin.

BACKGROUND: Diabetic nephropathy (DN) is one of the most common and serious complications of diabetes, and is the most important cause of death for diabetic patients. Baicalin (BAI) has anti-oxidative, anti-inflammatory and anti-apoptotic activities, which play a role in attenuating insulin resistance and protecting the kidney. Moreover, cell-specific targeting of renal tubular cells is an approach to enhance drug accumulation in the kidney. METHODS: Forty-five Sprague-Dawley rats were divided into four groups. A diabetes model was created using streptozotocin (STZ) intraperitoneally injection. The four groups included: Control group (n = 10), DN (n = 15), BAI treatment (BAI; n = 10) and BAI-LZM treatment (BAI-LZM; n = 10) groups. In the current study, the renoprotection and anti-fibrotic effects of BAI-lysozyme (LZM) conjugate were further investigated in rats with DN induced by STZ compared with BAI treatment alone. RESULTS: The results suggest that BAI-LZM better ameliorates renal impairment, metabolic disorder and renal fibrosis than BAI alone in rats with DN, and the potential regulatory mechanism likely involves inhibiting inflammation via the nuclear factor-κB signaling pathway, inhibiting extracellular matrix accumulation via the transforming growth factor-ß/Smad3 pathway and regulating cell proliferation via the insulin-like growth factor (IGF)-1/IGF-1 receptor/p38 Mitogen-activated protein kinase (MAPK) pathway. BAI and the kidney-targeted BAI-LZM can utilize the body's cytoprotective pathways to reactivate autophagy (as indicated by the autophagy markers mechanistic target of rapamycin and sirtuin 1 to ameliorate DN outcomes. CONCLUSIONS: Our data support the traditional use of S. baicalensis as an important anti-DN traditional chinese medicine (TCM), and BAI, above all BAI-LZM, is a promising source for the identification of molecules with anti-DN effects.

B-Myb Mediates Proliferation and Migration of Non-Small-Cell Lung Cancer via Suppressing IGFBP3.

B-Myb has been shown to play an important oncogenic role in several types of human cancers, including non-small-cell lung cancer (NSCLC). We previously found that B-Myb is aberrantly upregulated in NSCLC, and overexpression of B-Myb can significantly promote NSCLC cell growth and motility. In the present study, we have further investigated the therapeutic potential of B-Myb in NSCLC. Kaplan⁻Meier and Cox proportional hazards analysis indicated that high expression of B-Myb is significantly associated with poor prognosis in NSCLC patients. A loss-of-function study demonstrated that depletion of B-Myb resulted in significant inhibition of cell growth and delayed cell cycle progression in NSCLC cells. Notably, B-Myb depletion also decreased NSCLC cell migration and invasion ability as well as colony-forming ability. Moreover, an in vivo study demonstrated that B-Myb depletion caused significant inhibition of tumor growth in a NSCLC xenograft nude mouse model. A molecular mechanistic study by RNA-seq analysis revealed that B-Myb depletion led to deregulation of various downstream genes, including insulin-like growth factor binding protein 3 (IGFBP3). Overexpression of IGFBP3 suppressed the B-Myb-induced proliferation and migration, whereas knockdown of IGFBP3 significantly rescued the inhibited cell proliferation and motility caused by B-Myb siRNA (small interfering RNA). Expression and luciferase reporter assays revealed that B-Myb could directly suppress the expression of IGFBP3. Taken together, our results suggest that B-Myb functions as a tumor-promoting gene via suppressing IGFBP3 and could serve as a novel therapeutic target in NSCLC.

B-Myb Is Up-Regulated and Promotes Cell Growth and Motility in Non-Small Cell Lung Cancer.

B-Myb is a transcription factor that is overexpressed and plays an oncogenic role in several types of human cancers. However, its potential implication in lung cancer remains elusive. In the present study, we have for the first time investigated the expression profile of B-Myb and its functional impact in lung cancer. Expression analysis by quantificational real-time polymerase chain reaction (qRT-PCR) and immunohistochemistry demonstrated that B-Myb expression is aberrantly overexpressed in non-small cell lung cancer (NSCLC), and positively correlated with pathologic grade and clinical stage of NSCLC. A gain-of-function study revealed that overexpression of B-Myb significantly increases lung cancer cell growth, colony formation, migration, and invasion. Conversely, a loss-of-function study showed that knockdown of B-Myb decreases cell growth, migration, and invasion. B-Myb overexpression also promoted tumor growth in vivo in a NSCLC xenograft nude mouse model. A molecular mechanistic study by RNA-sequencing (RNA-seq) analysis showed that B-Myb overexpression causes up-regulation of various downstream genes (e.g., COL11A1, COL6A1, FN1, MMP2, NID1, FLT4, INSR, and CCNA1) and activation of multiple critical pathways (e.g., extracellular signal-regulated kinases (ERK) and phosphorylated-protein kinase B (Akt) signaling pathways) involved in cell proliferation, tumorigenesis, and metastasis. Collectively, our results indicate a tumor-promoting role for B-Myb in NSCLC and thus imply its potential as a target for the diagnosis and/or treatment of NSCLC.

Alkaline ceramidase 2 is a novel direct target of p53 and induces autophagy and apoptosis through ROS generation.

ACER2 is a critical sphingolipid metabolizing enzyme, and has been shown to be remarkably up-regulated following various stimuli such as DNA damage. However, the transcriptional regulatory mechanism of ACER2 gene and its potential role in the regulation of autophagy remain unknown. In this study, we have for the first time identified the human ACER2 gene promoter, and found that human ACER2 transcription is directly regulated by p53 and ACER2 is implicated in the induction of autophagy as well as apoptosis. A series of luciferase reporter assay demonstrated that ACER2 major promoter is located within its first intron where the consensus p53-binding sites exist. Consistently, forced expression of p53 significantly stimulated ACER2 transcription. Notably, p53-mediated autophagy and apoptosis were markedly enhanced by ACER2. Depletion of the essential autophagy gene ATG5 revealed that ACER2-induced autophagy facilitates its effect on apoptosis. Further studies clearly showed that ACER2-mediated autophagy and apoptosis are accompanied by ROS generation. In summary, our present study strongly suggests that ACER2 plays a pivotal role in p53-induced autophagy and apoptosis, and thus might serve as a novel and attractive molecular target for cancer treatment.

Methamphetamine modulates glutamatergic synaptic transmission in rat primary cultured hippocampal neurons.

Methamphetamine (METH) is a psychostimulant drug. Abuse of METH produces long-term behavioral changes including behavioral, sensitization, tolerance, and dependence. It induces neurotoxic effects in several areas of the brain via enhancing dopamine (DA) level abnormally, which may cause a secondary release of glutamate (GLU). However, repeated administration of METH still increases release of GLU even when dopamine content in tissue is significantly depleted. It implies that some other mechanisms are likely to involve in METH-induced GLU release. The goal of this study was to observe METH affected glutamatergic synaptic transmission in rat primary cultured hippocampal neurons and to explore the mechanism of METH modulated GLU release. Using whole-cell patch-clamp recordings, we found that METH (0.1-50.0µM) increased the frequency of spontaneous excitatory postsynaptic currents (sEPSCs) and miniature excitatory postsynaptic currents (mEPSCs). However, METH decreased the frequency of sEPSCs and mEPSCs at high concentration of 100µM. The postsynaptic NMDA receptor currents and P/Q-type calcium channel were not affected by the use of METH (10,100µM). METH did not present visible effect on N-type Ca(2+) channel current at the concentration lower than 50.0µM, but it was inhibited by use of METH at a 100µM. The effect of METH on glutamatergic synaptic transmission was not revered by pretreated with DA receptor antagonist SCH23390. These results suggest that METH directly modulated presynaptic GLU release at a different concentration, while dopaminergic system was not involved in METH modulated release of GLU in rat primary cultured hippocampal neurons.