Role of a differentially expressed cAMP phosphodiesterase in regulating the induction of resistance against oxidative damage in Leishmania donovani

Spermatozoa undergo exocytosis in response to agonists that induce Ca2+ influx and, in turn, activation of phosphoinositidase C, phospholipase C, phospholipase A2, and cAMP formation. Since the role of cAMP downstream of Ca2+ influx is unknown, this study investigated whether cAMP modulates phospholipase C or phospholipase A2 using a ram sperm model stimulated with A23187 and Ca2+. Exposure to dibutyryl-cAMP, phosphodiesterase inhibitors or forskolin resulted in enhancement of exocytosis. However, the effect was not due to stimulation of phospholipase C or phospholipase A2: in spermatozoa prelabelled with [3H]palmitic acid or [14C]arachidonic acid, these reagents did not enhance [3H]diacylglycerol formation or [14C]arachidonic acid release. Spermatozoa were treated with the phospholipase A2 inhibitor aristolochic acid, and dibutyryl-cAMP to test whether cAMP acts downstream of phospholipase A2. Under these conditions, exocytosis did not occur in response to A23187 and Ca2+. However, inclusion of dibutyryl-cAMP and the phospholipase A2 metabolite lysophosphatidylcholine did result in exocytosis (at an extent similar to that seen when cells were treated with A23187/Ca2+ and without the inhibitor). Inclusion of lysophosphatidylcholine alone, without dibutyryl-cAMP, enhanced exocytosis to a lesser extent, demonstrating that cAMP requires a phospholipase A2 metabolite to stimulate the final stages of exocytosis. These results indicate that cAMP may act downstream of phospholipase A2, exerting a regulatory role in the exocytosis triggered by physiological agonists.

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Ornithine decarboxylase of Leishmania donovani: Biochemical Properties and Possible Role of N-Terminal Extension

Protein and Peptide Letters ◽

10.2174/0929866521666140616115357 ◽

2015 ◽

Vol 22 (2) ◽

pp. 130-136 ◽

Cited By ~ 3

Author(s):

Mousumi Das ◽

Ritesh Kumar ◽

Vikash Dubey

Keyword(s):

Ornithine Decarboxylase ◽

Leishmania Donovani ◽

Biochemical Properties

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The Role of Reactive Oxygen Species in Tumor Treatment and its Impact on Bone Marrow Hematopoiesis

Current Drug Targets ◽

10.2174/1389450120666191021110208 ◽

2020 ◽

Vol 21 (5) ◽

pp. 477-498

Author(s):

Yongfeng Chen ◽

Xingjing Luo ◽

Zhenyou Zou ◽

Yong Liang

Keyword(s):

Reactive Oxygen Species ◽

Bone Marrow ◽

Oxidative Damage ◽

Tumor Cells ◽

Reactive Oxygen ◽

Oxygen Species ◽

Tumor Treatment ◽

Normal Cells ◽

Treatment And Prevention

Reactive oxygen species (ROS), an important molecule inducing oxidative stress in organisms, play a key role in tumorigenesis, tumor progression and recurrence. Recent findings on ROS have shown that ROS can be used to treat cancer as they accelerate the death of tumor cells. At present, pro-oxidant drugs that are intended to increase ROS levels of the tumor cells have been widely used in the clinic. However, ROS are a double-edged sword in the treatment of tumors. High levels of ROS induce not only the death of tumor cells but also oxidative damage to normal cells, especially bone marrow hemopoietic cells, which leads to bone marrow suppression and (or) other side effects, weak efficacy of tumor treatment and even threatening patients’ life. How to enhance the killing effect of ROS on tumor cells while avoiding oxidative damage to the normal cells has become an urgent issue. This study is a review of the latest progress in the role of ROS-mediated programmed death in tumor treatment and prevention and treatment of oxidative damage in bone marrow induced by ROS.

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Bioinformatics Analysis and Validation of Differentially Expressed MicroRNAs with Their Target Genes Involved in GLP-1RA Facilitated Osteogenesis

Current Bioinformatics ◽

10.2174/1574893615999200508091615 ◽

2020 ◽

Vol 15 ◽

Author(s):

Na Wang ◽

Yukun Li ◽

Sijing Liu ◽

Liu Gao ◽

Chang Liu ◽

...

Keyword(s):

High Throughput Sequencing ◽

Target Genes ◽

Bioinformatics Analysis ◽

Differentially Expressed ◽

Functional Study ◽

Regulation Network ◽

Glucagon Like Peptide 1 ◽

G Protein Coupled ◽

Lower Expression

Background: Recent studies revealed that the hypoglycemic hormone, glucagon-like peptide-1 (GLP-1), acted as an important modulator in osteogenesis of bone marrow derived mesenchymal stem cells (BMSCs). Objectives: The aim of this study was to identify the specific microRNA (miRNA) using bioinformatics analysis and validate the presence of differentially expressed microRNAs with their target genes after GLP-1 receptor agonist (GLP-1RA) administration involved in ostogenesis of BMSCs. Methods: MiRNAs were extracted from BMSCs after 5 days’ treatment and sent for high-throughput sequencing for differentially expressed (DE) miRNAs analyses. Then the expression of the DE miRNAs verified by the real-time RT-PCR analyses. Target genes were predicted, and highly enriched GOs and KEGG pathway analysis were conducted using bioinformatics analysis. For the functional study, two of the target genes, SRY (sex determining region Y)-box 5 (SOX5) and G protein-coupled receptor 84 (GPR84), were identified. Results: A total of 5 miRNAs (miRNA-509-5p, miRNA-547-3p, miRNA-201-3p, miRNA-201-5p, and miRNA-novel-272-mature) were identified differentially expressed among groups. The expression of miRNA-novel-272-mature were decreased during the osteogenic differentiation of BMSCs, and GLP-1RA further decreased its expression. MiRNA-novel-272-mature might interact with its target mRNAs to enhance osteogenesis. The lower expression of miRNA-novel-272-mature led to an increase in SOX5 and a decrease in GPR84 mRNA expression, respectively. Conclusions: Taken together, these results provide further insights to the pharmacological properties of GLP-1RA and expand our knowledge on the role of miRNAs-mRNAs regulation network in BMSCs’ differentiation.

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Genome-Wide Identification and Characterization of Long Noncoding RNAs Involved in Chinese Wheat Mosaic Virus Infection of Nicotiana benthamiana

Biology ◽

10.3390/biology10030232 ◽

2021 ◽

Vol 10 (3) ◽

pp. 232

Author(s):

Weiran Zheng ◽

Haichao Hu ◽

Qisen Lu ◽

Peng Jin ◽

Linna Cai ◽

...

Keyword(s):

Virus Infection ◽

Mosaic Virus ◽

Nicotiana Benthamiana ◽

Noncoding Rnas ◽

Long Noncoding Rnas ◽

Differentially Expressed ◽

Genome Wide ◽

Chinese Wheat

Recent studies have shown that a large number of long noncoding RNAs (lncRNAs) can regulate various biological processes in animals and plants. Although lncRNAs have been identified in many plants, they have not been reported in the model plant Nicotiana benthamiana. Particularly, the role of lncRNAs in plant virus infection remains unknown. In this study, we identified lncRNAs in N. benthamiana response to Chinese wheat mosaic virus (CWMV) infection by RNA sequencing. A total of 1175 lncRNAs, including 65 differentially expressed lncRNAs, were identified during CWMV infection. We then analyzed the functions of some of these differentially expressed lncRNAs. Interestingly, one differentially expressed lncRNA, XLOC_006393, was found to participate in CWMV infection as a precursor to microRNAs in N. benthamiana. These results suggest that lncRNAs play an important role in the regulatory network of N. benthamiana in response to CWMV infection.

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