scholarly journals Alcohol-and-HIV-Induced Lysosomal Dysfunction Regulates Extracellular Vesicles Secretion in Vitro and in Liver-Humanized Mice

Biology ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 29
Author(s):  
Raghubendra Singh Dagur ◽  
Moses New-Aaron ◽  
Murali Ganesan ◽  
Weimin Wang ◽  
Svetlana Romanova ◽  
...  

Background: Alcohol abuse is common in people living with HIV-1 and dramaticallyenhances the severity of HIV-induced liver damage by inducing oxidative stress and lysosomaldysfunction in the liver cells. We hypothesize that the increased release of extracellular vesicles(EVs) in hepatocytes and liver humanized mouse model is linked to lysosome dysfunction. Methods:The study was performed on primary human hepatocytes and human hepatoma RLWXP-GFP (Huh7.5 cells stably transfected with CYP2E1 and XPack-GFP) cells and validated on ethanol-fed liverhumanizedfumarylacetoacetate hydrolase (Fah)-/-, Rag2-/-, common cytokine receptor gamma chainknockout (FRG-KO) mice. Cells and mice were infected with HIV-1ADA virus. Results: We observedan increase in the secretion of EVs associated with a decrease in lysosomal activity and expressionof lysosomal-associated membrane protein 1. Next-generation RNA sequencing of primary humanhepatocytes revealed 63 differentially expressed genes, with 13 downregulated and 50 upregulatedgenes in the alcohol–HIV-treated group. Upstream regulator analysis of differentially expressedgenes through Ingenuity Pathway Analysis identified transcriptional regulators affecting downstreamgenes associated with increased oxidative stress, lysosomal associated disease, and function andEVs biogenesis. Our in vitro findings were corroborated by in vivo studies on human hepatocytetransplantedhumanized mice, indicating that intensive EVs’ generation by human hepatocytes andtheir secretion to serum was associated with increased oxidative stress and reduction in lysosomalactivities triggered by HIV infection and ethanol diet. Conclusion: HIV-and-ethanol-metabolisminducedEVs release is tightly controlled by lysosome status in hepatocytes and participates in thedevelopment of double-insult-induced liver injury.

Author(s):  
Birte Weber ◽  
Niklas Franz ◽  
Ingo Marzi ◽  
Dirk Henrich ◽  
Liudmila Leppik

AbstractDue to the continued high incidence and mortality rate worldwide, there is a need to develop new strategies for the quick, precise, and valuable recognition of presenting injury pattern in traumatized and poly-traumatized patients. Extracellular vesicles (EVs) have been shown to facilitate intercellular communication processes between cells in close proximity as well as distant cells in healthy and disease organisms. miRNAs and proteins transferred by EVs play biological roles in maintaining normal organ structure and function under physiological conditions. In pathological conditions, EVs change the miRNAs and protein cargo composition, mediating or suppressing the injury consequences. Therefore, incorporating EVs with their unique protein and miRNAs signature into the list of promising new biomarkers is a logical next step. In this review, we discuss the general characteristics and technical aspects of EVs isolation and characterization. We discuss results of recent in vitro, in vivo, and patients study describing the role of EVs in different inflammatory diseases and traumatic organ injuries. miRNAs and protein signature of EVs found in patients with acute organ injury are also debated.


Blood ◽  
2021 ◽  
Author(s):  
Kaushik Das ◽  
Shiva Keshava ◽  
Shabbir A Ansari ◽  
Vijay Kumar Reddy Kondreddy ◽  
Charles Esmon ◽  
...  

Recombinant FVIIa (rFVIIa) is used as a hemostatic agent to treat bleeding disorders in hemophilia patients with inhibitors and other groups of patients. Our recent studies showed that FVIIa binds endothelial cell protein C receptor (EPCR) and induces protease-activated receptor 1 (PAR1)-mediated biased signaling. The importance of FVIIa-EPCR-PAR1-mediated signaling in hemostasis is unknown. In the present study, we show that FVIIa induces the release of extracellular vesicles (EVs) from endothelial cells both in vitro and in vivo. Silencing of EPCR or PAR1 in endothelial cells blocked the FVIIa-induced generation of EVs. Consistent with these data, FVIIa treatment enhanced the release of EVs from murine brain endothelial cells isolated from wild-type, EPCR overexpressors, and PAR1-R46Q mutant mice, but not EPCR-deficient or PAR1-R41Q mutant mice. In vivo studies revealed that administration of FVIIa to wild-type, EPCR overexpressors, and PAR1-R46Q mutant mice, but not EPCR-deficient or PAR1-R41Q mutant mice, increase the number of circulating EVs. EVs released in response to FVIIa treatment exhibit enhanced procoagulant activity. Infusion of FVIIa-generated EVs and not control EVs to platelet-depleted mice increased thrombin generation at the site of injury and reduced blood loss. Administration of FVIIa-generated EVs or generation of EVs endogenously by administering FVIIa augmented the hemostatic effect of FVIIa. Overall, our data reveal that FVIIa treatment, through FVIIa-EPCR-PAR1 signaling, releases EVs from the endothelium into the circulation, and these EVs contribute to the hemostatic effect of FVIIa.


2019 ◽  
Vol 8 (5) ◽  
pp. 680 ◽  
Author(s):  
Amjad Khan ◽  
Muhammad Ikram ◽  
Tahir Muhammad ◽  
Junsung Park ◽  
Myeong Ok Kim

Cadmium (Cd), a nonbiodegradable heavy metal and one of the most neurotoxic environmental and industrial pollutants, promotes disturbances in major organs and tissues following both acute and chronic exposure. In this study, we assessed the neuroprotective potential of caffeine (30 mg/kg) against Cd (5 mg/kg)-induced oxidative stress-mediated neuroinflammation, neuronal apoptosis, and cognitive deficits in male C57BL/6N mice in vivo and in HT-22 and BV-2 cell lines in vitro. Interestingly, our findings indicate that caffeine markedly reduced reactive oxygen species (ROS) and lipid peroxidation (LPO) levels and enhanced the expression of nuclear factor-2 erythroid-2 (Nrf-2) and hemeoxygenase-1 (HO-1), which act as endogenous antioxidant regulators. Also, 8-dihydro-8-oxoguanine (8-OXO-G) expression was considerably reduced in the caffeine-treated group as compared to the Cd-treated group. Similarly, caffeine ameliorated Cd-mediated glial activation by reducing the expression of glial fibrillary acidic protein (GFAP), ionized calcium-binding adapter molecule 1 (Iba-1), and other inflammatory mediators in the cortical and hippocampal regions of the mouse brain. Moreover, caffeine markedly attenuated Cd-induced neuronal loss, synaptic dysfunction, and learning and cognitive deficits. Of note, nuclear factor-2 erythroid-2 (Nrf-2) gene silencing and nuclear factor-κB (NF-κB) inhibition studies revealed that caffeine exerted neuroprotection via regulation of Nrf-2- and NF-κB-dependent mechanisms in the HT-22 and BV-2 cell lines, respectively. On the whole, these findings reveal that caffeine rescues Cd-induced oxidative stress-mediated neuroinflammation, neurodegeneration, and memory impairment. The present study suggests that caffeine might be a potential antioxidant and neuroprotective agent against Cd-induced neurodegeneration.


2004 ◽  
Vol 96 (2) ◽  
pp. 784-791 ◽  
Author(s):  
Jay B. Dean ◽  
Daniel K. Mulkey ◽  
Richard A. Henderson ◽  
Stephanie J. Potter ◽  
Robert W. Putnam

Hyperoxia is a popular model of oxidative stress. However, hyperoxic gas mixtures are routinely used for chemical denervation of peripheral O2 receptors in in vivo studies of respiratory control. The underlying assumption whenever using hyperoxia is that there are no direct effects of molecular O2 and reactive O2 species (ROS) on brain stem function. In addition, control superfusates used routinely for in vitro studies of neurons in brain slices are, in fact, hyperoxic. Again, the assumption is that there are no direct effects of O2 and ROS on neuronal activity. Research contradicts this assumption by demonstrating that O2 has central effects on the brain stem respiratory centers and several effects on neurons in respiratory control areas; these need to be considered whenever hyperoxia is used. This mini-review summarizes the long-recognized, but seldom acknowledged, paradox of respiratory control known as hyperoxic hyperventilation. Several proposed mechanisms are discussed, including the recent hypothesis that hyperoxic hyperventilation is initiated by increased production of ROS during hyperoxia, which directly stimulates central CO2 chemoreceptors in the solitary complex. Hyperoxic hyperventilation may provide clues into the fundamental role of redox signaling and ROS in central control of breathing; moreover, oxidative stress may play a role in respiratory control dysfunction. The practical implications of brain stem O2 and ROS sensitivity are also considered relative to the present uses of hyperoxia in respiratory control research in humans, animals, and brain stem tissues. Recommendations for future research are also proposed.


Planta Medica ◽  
2018 ◽  
Vol 84 (18) ◽  
pp. 1318-1333 ◽  
Author(s):  
Ligen Lin ◽  
Fayang Zhou ◽  
Shengnan Shen ◽  
Tian Zhang

AbstractLiver fibrosis is a wound-healing response characterized by the accumulation of extracellular matrix following various liver injuries, which results in the deformation of the normal liver architecture and the development of liver cirrhosis and even hepatocellular carcinoma. Numerous in vitro and in vivo studies indicated that oxidative stress mediates the initiation and progression of liver fibrosis. Overaccumulation of reactive oxygen species disrupts macromolecules, induces necrosis and apoptosis of hepatocytes, stimulates the production of pro-fibrogenic mediators, and directly activates hepatic stellate cells, thereby resulting in liver damage and initiating liver fibrosis. Ameliorating oxidative stress is a potential therapeutic strategy for the treatment of liver fibrosis. Natural antioxidants have attracted increasing attention in treating liver fibrosis due to their safety and efficacy. In this review, the pathogenesis of liver fibrosis and the role of oxidative stress in liver fibrosis were discussed. Naturally occurring antioxidants that can treat and prevent liver fibrosis were summarized. Advances in clinical trials were also presented. The main purpose of this review is to provide a comprehensive and up-to-date knowledge from the biological importance of oxidative stress in liver fibrosis to representative antioxidants for treating liver fibrosis. Naturally occurring antioxidants show a potential for further investigations as lead compounds in fighting liver fibrosis.


2019 ◽  
pp. 1-11
Author(s):  
A. F. Ogori ◽  
A. T. Girgih ◽  
J. O. Abu ◽  
M. O. Eke

The bioactive peptides produced by enzymatic hydrolysis, acid hydrolysis and fermentation approach have been identified and used widely in research. These methods are important in enhancement or prevention and management of chronic diseases that are ravaging the world such as type -2-diabetes, hypertension, oxidative stress, cancer, and obesity. Sources of bioactive peptides have been established ranging from plant to animal and marine foods that have pharmacological effects; however these effects are dependent on target cells and peptides structure and conformations.  Plants such as hemp and animal source such as milk among others validate the findings of In vitro and In-vivo studies and the efficiency of these bioactive peptides in the management of certain chronic diseases. This article reviews the literature on bioactive peptides with concern on food sources, production and bioactive peptides application in enhancement of health and management of hypertension, diabetes and oxidative stress.  Future research efforts on bioactive peptides should be directed towards elucidating specific sequenced bioactive peptides and their molecular mechanisms, through In-vivo and In-vitro studies for specific health condition in human using nutrigenomics and peptideomic approaches.


2019 ◽  
pp. 1-11
Author(s):  
A. F. Ogori ◽  
A. T. Girgih ◽  
J. O. Abu ◽  
M. O. Eke

The bioactive peptides produced by enzymatic hydrolysis, acid hydrolysis and fermentation approach have been identified and used widely in research. These methods are important in enhancement or prevention and management of chronic diseases that are ravaging the world such as type -2-diabetes, hypertension, oxidative stress, cancer, and obesity. Sources of bioactive peptides have been established ranging from plant to animal and marine foods that have pharmacological effects; however these effects are dependent on target cells and peptides structure and conformations.  Plants such as hemp and animal source such as milk among others validate the findings of In vitro and In-vivo studies and the efficiency of these bioactive peptides in the management of certain chronic diseases. This article reviews the literature on bioactive peptides with concern on food sources, production and bioactive peptides application in enhancement of health and management of hypertension, diabetes and oxidative stress.  Future research efforts on bioactive peptides should be directed towards elucidating specific sequenced bioactive peptides and their molecular mechanisms, through In-vivo and In-vitro studies for specific health condition in human using nutrigenomics and peptideomic approaches.


2022 ◽  
Author(s):  
Marina Feric ◽  
Azadeh Sarfallah ◽  
Furqan Dar ◽  
Dmitry Temiakov ◽  
Rohit V Pappu ◽  
...  

Phase separation organizes many membraneless structures in cells. The functional consequences of concentrating cellular machinery into biomolecular condensates, however, is largely unclear. Here, we use in vitro reconstitutions, in vivo studies, and computational modelling to uncover structure-function relationships of mitochondrial (mt-) transcriptional condensates. In vitro, we find that the core mt-transcription machinery — consisting of POLRMT, TFAM, TFB2M, and DNA — forms viscoelastic, multi-phasic condensates. Strikingly, the rates of condensate-mediated transcription are considerably lower than equivalent reactions in bulk solution. Dampened rates are associated with reduced diffusivities of components that become kinetically arrested in non-equilibrium, vesicular condensates. Perturbation of mt-components in vivo and computational simulations recapitulate the transcription-dependent reorganizations observed in vitro. Our findings demonstrate close, bidirectional interdependence between structure and function of transcriptional condensates.


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