Mitochondrial nanomedicine: Subcellular organelle-specific delivery of molecular medicines

Endosome fractions were isolated from rat liver homogenates on the basis of the subcellular distribution of circulating ligands, e.g. 125I-asialotransferrin internalized by hepatocytes by a receptor-mediated process. The distribution of endocytosed 125I-asialotransferrin 1-2 min and 15 min after uptake by liver and a monensin-activated Mg2+-dependent ATPase activity coincided on linear gradients of sucrose and Nycodenz. The monensin-activated Mg2+-ATPase was enriched relative to the liver homogenates up to 60-fold in specific activity in the endosome fractions. Contamination of the endosome fractions by lysosomes, endoplasmic reticulum, mitochondria, plasma membranes and Golgi-apparatus components was low. By use of 9-aminoacridine, a probe for pH gradients, the endosome vesicles were shown to acidify on addition of ATP. Acidification was reversed by addition of monensin. The results indicate that endosome fractions contain an ATP-driven proton pump. The ionophore-activated Mg2+-ATPase in combination with the presence of undegraded ligands in the endosome fractions emerge as linked markers for this new subcellular organelle.

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Super Resolution Microscopy and Deep Learning Identify Zika Virus Reorganization of the Endoplasmic Reticulum

10.1101/2020.05.12.091611 ◽

2020 ◽

Author(s):

Rory K. M. Long ◽

Kathleen P. Moriarty ◽

Ben Cardoen ◽

Guang Gao ◽

A. Wayne Vogl ◽

...

Keyword(s):

Endoplasmic Reticulum ◽

Deep Learning ◽

Viral Replication ◽

Zika Virus ◽

Deep Neural Networks ◽

Super Resolution ◽

Zikv Infection ◽

Subcellular Organelle ◽

Infected Cells ◽

Super Resolution Microscopy

AbstractThe endoplasmic reticulum (ER) is a complex subcellular organelle composed of diverse structures such as tubules, sheets and tubular matrices. Flaviviruses such as Zika virus (ZIKV) induce reorganization of endoplasmic reticulum (ER) membranes to facilitate viral replication. Here, using 3D super resolution microscopy, ZIKV infection is shown to induce the formation of dense tubular matrices associated with viral replication in the central ER. Viral non-structural proteins NS4B and NS2B associate with replication complexes within the ZIKV-induced tubular matrix and exhibit distinct ER distributions outside this central ER region. Deep neural networks trained to identify ZIKV-infected versus mock-infected cells successfully identified ZIKV-induced central ER tubular matrices as a determinant of viral infection. Super resolution microscopy and deep learning are therefore able to identify and localize morphological features of the ER and may be of use to screen for inhibitors of infection by ER-reorganizing viruses.

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Network Organisation and the Dynamics of Tubules in the Endoplasmic Reticulum

10.1101/2020.03.11.987891 ◽

2020 ◽

Author(s):

H. Perkins ◽

P. Ducluzaux ◽

P. Woodman ◽

V. Allan ◽

T. Waigh

Keyword(s):

Endoplasmic Reticulum ◽

Binary Classification ◽

Persistence Length ◽

Gaussian Mixture ◽

Live Cells ◽

Hereditary Spastic Paraplegias ◽

Membrane Contact Sites ◽

Subcellular Organelle ◽

Membrane Contact ◽

Network Organisation

ABSTRACTThe endoplasmic reticulum (ER) is a eukaryotic subcellular organelle composed of tubules and sheet-like areas of membrane connected at junctions. The tubule network is highly dynamic and undergoes rapid and continual rearrangement. There are currently few tools to evaluate network organisation and dynamics. We quantified ER network organisation in Vero and MRC5 cells, and developed a classification system for ER dynamics in live cells. The persistence length, tubule length, junction coordination number and angles of the network were quantified. Hallmarks of imbalances in ER tension, indications of interactions with microtubules and other subcellular organelles, and active reorganisation and dynamics were observed. Live cell ER tubule dynamics were classified using a Gaussian mixture model, defining tubule motion as active or thermal and conformational phase space analysis allowed this classification to be refined by tubule curvature states.STATEMENT OF SIGNIFICANCEThe endoplasmic reticulum (ER), a subcellular organelle, is an underexplored real-world example of active matter. Many processes essential to cell survival are performed by the ER, the efficacy of which may depend on its organisation and dynamics. Abnormal ER morphology is linked to diseases such as hereditary spastic paraplegias and it is possible that the dynamics are also implicated. Therefore, analysing the ER network in normal cells is important for the understanding of disease-related alterations. In this work, we outline the first thorough quantification methods for determining ER organisation and dynamics, deducing that tubule motion has a binary classification as active or thermal. Active reorganisation and dynamics along with indications of tension imbalances and membrane contact sites were observed.

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Early reversal cardiac with esmolol in hypertensive rats: The role of subcellular organelle phenotype

Pharmacological Reports ◽

10.1016/j.pharep.2019.06.013 ◽

2019 ◽

Vol 71 (6) ◽

pp. 1125-1132

Author(s):

Begoña Quintana-Villamandos ◽

María Jesús Delgado-Martos ◽

Emilio Delgado-Baeza

Keyword(s):

Hypertensive Rats ◽

Subcellular Organelle

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All-in-one mitochondria-targeted NIR-II fluorophores for cancer therapy and imaging

Chemical Science ◽

10.1039/d0sc04727a ◽

2021 ◽

Author(s):

Yujia Zheng ◽

Qianqian Li ◽

Jing Wu ◽

Ziyi Luo ◽

Wenyi Zhou ◽

...

Keyword(s):

Cancer Therapy ◽

Small Molecule ◽

Disease Diagnosis ◽

Diagnosis And Treatment ◽

Early Disease ◽

Subcellular Organelle ◽

Organelle Targeting

Small-molecule subcellular organelle-targeting theranostic probes are crucial for early disease diagnosis and treatment.

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Prenatal GABAB1 and GABAB2 receptors: Cellular and subcellular organelle localization in early fetal rat cortical neurons

Synapse ◽

10.1002/syn.20332 ◽

2006 ◽

Vol 60 (8) ◽

pp. 557-566 ◽

Cited By ~ 5

Author(s):

S.P. Li ◽

H.Y. Lee ◽

M.S. Park ◽

J.Y. Bahk ◽

B.C. Chung ◽

...

Keyword(s):

Cortical Neurons ◽

Subcellular Organelle ◽

Fetal Rat ◽

Rat Cortical Neurons

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Mitochondrial damage: a possible mechanism of the “topical” phase of NSAID induced injury to the rat intestine

Gut ◽

10.1136/gut.41.3.344 ◽

1997 ◽

Vol 41 (3) ◽

pp. 344-353 ◽

Cited By ~ 203

Author(s):

S Somasundaram ◽

S Rafi ◽

J Hayllar ◽

G Sigthorsson ◽

M Jacob ◽

...

Keyword(s):

Electron Microscopy ◽

Small Intestine ◽

Electron Transport ◽

Oxidative Phosphorylation ◽

In Vivo Studies ◽

Tolerability Profile ◽

Marker Enzyme ◽

Subcellular Organelle

Background—The “topical” effect of non-steroidal anti-inflammatory drugs (NSAIDs) seems to be an important cause of NSAID induced gastrointestinal damage.Aim—To examine the possible mechanism of the “topical” phase of damage in the small intestine.Methods—Electron microscopy and subcellular organelle marker enzyme studies were done in rat small intestine after oral administration of indomethacin (doses varied between 5 and 30 mg/kg). The effect of conventional and non-acidic NSAIDs on rat liver mitochondrial respiration was measured in vitro in a Clarke-type oxygen electrode.Results—The subcellular organelle marker enzymes showed mitochondrial and brush border involvement within an hour of indomethacin administration. Electron microscopy showed dose dependent mitochondrial changes following indomethacin administration consistent with uncoupling of oxidative phosphorylation (or inhibition of electron transport) which were indistinguishable from those seen with the uncoupler dinitrophenol. Parenteral indomethacin caused similar changes, but not in rats with ligated bile ducts. A range of NSAIDs, but not paracetamol or non-acidic NSAIDs which have a favourable gastrointestinal tolerability profile, uncoupled oxidative phosphorylation in vitro at micromolar concentrations and inhibited respiration at higher concentrations. In vivo studies with nabumetone and aspirin further suggested that uncoupling or inhibition of electron transport underlies the “topical” phase of NSAID induced damage.Conclusion—Collectively, these studies suggest that NSAID induced changes in mitochondrial energy production may be an important component of the “topical” phase of damage induction.

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A fine structure study of the anthocodium in Renilla mülleri. Evidence for the existence of a bioluminescent organelle, the luminelle.

The Journal of Cell Biology ◽

10.1083/jcb.64.1.15 ◽

1975 ◽

Vol 64 (1) ◽

pp. 15-28 ◽

Cited By ~ 18

Author(s):

B O Spurlock ◽

M J Cormier

Keyword(s):

Fine Structure ◽

Green Fluorescent Protein ◽

Fluorescent Protein ◽

Structure Study ◽

Green Fluorescence ◽

Subcellular Structure ◽

Subcellular Organelle ◽

Green Fluorescent ◽

Structural Entity

A fine structure study of the anthocodium of the sea pansy, Renilla mülleri, was undertaken. The anthocodium, a known site of bioluminescence, was selected in order to determine whether a structural entity could be found which would satisfy the biochemical and physiological features associated with the known sites of bioluminescence in this animal. These sites, termed lumisomes, have previously been shown to be small (0.1-0.2 mum), membrane-enclosed vesicles which contain all the proteins necessary for bioluminescence and its immediate control. One of the lumisomal proteins is an intensely green fluorescent protein and has been used as a probe for the detection of the cellular sites of bioluminescence. This green fluorescence was associated only with gastrodermal cells. We report the identification of a unique morphological entity, restricted to the cells of the gastrodermis, which satisfies the biochemical and physiological requirements for bioluminescence in Renilla. It is a large (4-6 mum), membrane-bounded subcellular organelle comparable in size to a subcellular structure whose green fluorescence is typically associated with the in vivo bioluminescence. Furthermore, it is filled with smaller membrane-bounded vesicles which have the same size and shape as the lumisomes. We suggest that the organelle identified in this study be termed a luminelle.

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Characterization of the energy-dependent calcium binding of a mitochondrial fraction isolated from bovine intrapulmonary vein

Canadian Journal of Physiology and Pharmacology ◽

10.1139/y79-165 ◽

1979 ◽

Vol 57 (10) ◽

pp. 1107-1113 ◽

Cited By ~ 5

Author(s):

Dennis B. McNamara ◽

Marie-Jeanne Roulet ◽

Albert L. Hyman ◽

Philip J. Kadowitz

Keyword(s):

Calcium Binding ◽

Succinic Dehydrogenase ◽

Mitochondrial Fraction ◽

Time Interval ◽

Marker Enzyme ◽

Mitochondrial Marker ◽

Fold Enrichment ◽

Subcellular Organelle ◽

Energy Dependent

A mitochondrial-enriched fraction was isolated from bovine intrapulmonary vein; this fraction had a three- to four-fold enrichment factor for succinic dehydrogenase, a mitochondrial marker enzyme, and bound calcium in an azide-sensitive, energy-dependent fashion using either ATP or succinate as substrate. The calcium binding was sensitive to the concentrations of H+, ATP, Ca2+, and mitochondrial fraction. Binding and accumulation were time dependent, reaching at 10–12 min a plateau which was maintained over the time interval studied, i.e. 18 min. At the plateau, maximal binding was 221 ± 8.64 and maximal accumulation was 285 ± 20.2 nmol Ca2+/mg protein. The mitochondrial-enriched fraction contained an azide-sensitive, Mg2+-dependent, Ca2+-stimulated ATPase (Mg2+ + Ca2+ = 25.59 ± 1.03, Ca2+ = 3.96 ± 1.06 μmol P1/mg protein per hour). This study is the first to report the isolation from intrapulmonary vein of a subcellular organelle capable of binding calcium in an energy-dependent fashion; furthermore, it confirms and extends the observations of others that mitochondria may contribute to intracellular calcium homeostasis in vascular smooth muscle.

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Forsythiasides-Rich Extract From Forsythiae Fructus Inhibits Mast Cell Degranulation by Enhancing Mitochondrial Ca2+ Uptake

Frontiers in Pharmacology ◽

10.3389/fphar.2021.696729 ◽

2021 ◽

Vol 12 ◽

Author(s):

Ruijuan Qi ◽

Yuan Kang ◽

Ximeng Li ◽

Xiaoyu Zhang ◽

Yixin Han ◽

...

Keyword(s):

Allergic Diseases ◽

Underlying Mechanism ◽

Mechanism Study ◽

Isolated Mitochondria ◽

Theoretical Support ◽

Subcellular Organelle ◽

Underlying Mechanisms ◽

G Protein Coupled

Mast cells (MCs) activated via IgE/FcεRI or MAS-related G protein coupled receptor (Mrgpr)-mediated pathway can release granules that play prominent roles in hypersensitivity reactions. Forsythiae Fructus, a well-known traditional Chinese medicine, has been clinically used for allergic diseases. Although previous studies indicated that Forsythiae Fructus extract inhibited compound 48/80-induced histamine release from MCs, its effect on IgE-dependent MC degranulation and possible underlying mechanisms remain to be explored. Herein, we prepared the forsythiasides-rich extract (FRE) and investigated its action on MC degranulation and explored its underlying mechanism. Our data showed that FRE could dampen IgE/FcεRI- and Mrgpr-mediated MC degranulation in vitro and in vivo. Mechanism study indicated that FRE decreased cytosolic Ca2+ (Ca2+[c]) level rapidly and reversibly. Moreover, FRE decreased Ca2+[c] of MCs independent of plasma membrane Ca2+-ATPase (PMCA), sarco/endoplasmic Ca2+-ATPase (SERCA) and Na+/Ca2+ exchanger (NCX). While, along with Ca2+[c] decrease, the increase of mitochondrial Ca2+ (Ca2+[m]) occurred simultaneously in FRE-treated RBL-2H3 cells. In the isolated mitochondria, FRE also promoted the subcellular organelle to uptake more extramitochondrial Ca2+. In conclusion, by increasing Ca2+[m] uptake, FRE decreases Ca2+[c] level to suppress MC degranulation. Our findings may provide theoretical support for the clinical application of Forsythiae Fructus on allergy and other MC-involved diseases.

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