Targeting the Lowest Concentration of a Toxin That Induces a Detectable Metabolic Response in Living Organisms: Time-Resolved In Vivo 2D NMR during a Concentration Ramp

Abscisic acid (ABA) is a hormone with a very long evolutionary history, dating back to the earliest living organisms, of which modern (ABA-producing) cyanobacteria are likely the descendants, well before separation of the plant and animal kingdoms, with a conserved role as a signal regulating cell responses to environmental challenges. In mammals, nanomolar ABA controls the metabolic response to glucose availability by stimulating glucose uptake in skeletal muscle and adipose tissue with an insulin-independent mechanism and increasing energy expenditure in the brown and white adipose tissues. Activation by ABA of AMP-dependent kinase (AMPK), in contrast to the insulin-induced activation of AMPK-inhibiting Akt, is responsible for stimulation of GLUT4-mediated muscle glucose uptake, and for the browning effect on white adipocytes. Intake of micrograms per Kg body weight of ABA improves glucose tolerance in both normal and in borderline subjects and chronic intake of such a dose of ABA improves blood glucose, lipids and morphometric parameters (waist circumference and body mass index) in borderline subjects for prediabetes and the metabolic syndrome. This review summarizes the most recent results obtained in vivo with microgram amounts of ABA, the role of the receptor LANCL2 in the hormone’s action and the significance of the endowment by mammals of two different hormones controlling the metabolic response to glucose availability. Finally, open issues in need of further investigation and perspectives for the clinical use of nutraceutical ABA are discussed.

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1D “Spikelet” Projections from Heteronuclear 2D NMR Data—Permitting 1D Chemometrics While Preserving 2D Dispersion

Metabolites ◽

10.3390/metabo9010016 ◽

2019 ◽

Vol 9 (1) ◽

pp. 16 ◽

Cited By ~ 3

Author(s):

Maryam Tabatabaei Anaraki ◽

Wolfgang Bermel ◽

Rudraksha Dutta Majumdar ◽

Ronald Soong ◽

Myrna Simpson ◽

...

Keyword(s):

1H Nmr ◽

13C Nmr ◽

2D Nmr ◽

Complex Samples ◽

Software Packages ◽

Nmr Data ◽

Wide Range ◽

Spectral Dispersion ◽

Living Organisms

Nuclear magnetic resonance (NMR) spectroscopy is a powerful tool for the non-targeted metabolomics of intact biofluids and even living organisms. However, spectral overlap can limit the information that can be obtained from 1D 1H NMR. For example, magnetic susceptibility broadening in living organisms prevents any metabolic information being extracted from solution-state 1D 1H NMR. Conversely, the additional spectral dispersion afforded by 2D 1H-13C NMR allows a wide range of metabolites to be assigned in-vivo in 13C enriched organisms, as well as a greater depth of information for biofluids in general. As such, 2D 1H-13C NMR is becoming more and more popular for routine metabolic screening of very complex samples. Despite this, there are only a very limited number of statistical software packages that can handle 2D NMR datasets for chemometric analysis. In comparison, a wide range of commercial and free tools are available for analysis of 1D NMR datasets. Overtime, it is likely more software solutions will evolve that can handle 2D NMR directly. In the meantime, this application note offers a simple alternative solution that converts 2D 1H-13C Heteronuclear Single Quantum Correlation (HSQC) data into a 1D “spikelet” format that preserves not only the 2D spectral information, but also the 2D dispersion. The approach allows 2D NMR data to be converted into a standard 1D Bruker format that can be read by software packages that can only handle 1D NMR data. This application note uses data from Daphnia magna (water fleas) in-vivo to demonstrate how to generate and interpret the converted 1D spikelet data from 2D datasets, including the code to perform the conversion on Bruker spectrometers.

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2D NMR studies on muscle and cerebral metabolism in vivo

Journal de Chimie Physique ◽

10.1051/jcp/1994910697 ◽

1994 ◽

Vol 91 ◽

pp. 697-703 ◽

Cited By ~ 2

Author(s):

B Gillet ◽

BT Doan ◽

C Verre-Sebrie ◽

O Fedeli ◽

JC Beloeil ◽

...

Keyword(s):

Cerebral Metabolism ◽

2D Nmr ◽

Nmr Studies

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In vivo Experiments of Natural Products Protection of Antagonistic Effects of Lead on Iron

Revista de Chimie ◽

10.37358/rc.17.12.5969 ◽

2018 ◽

Vol 68 (12) ◽

pp. 2747-2751

Author(s):

Marioara Nicula ◽

Nicolae Pacala ◽

Lavinia Stef ◽

Ioan Pet ◽

Dorel Dronca ◽

...

Keyword(s):

Aquatic Environment ◽

Iron Homeostasis ◽

Iron Concentration ◽

Antagonistic Effect ◽

Tissue Samples ◽

Antagonistic Effects ◽

In Vivo Experiments ◽

Living Organisms ◽

Toxic Potential

Living organisms take nutrients from the environment, and together with them, substances with toxic potential � such as heavy metals. Lead is one common metal pollutant especially in aquatic environment, from where the fish can be intoxicated very easily. Bioavailability, distribution, toxic action, synergistic and antagonistic effects are characteristics which can alter the fish health. Our experimental study followed the effects of lead overload in water on iron distribution, in different tissues sample Carassius gibelio Bloch fish. We performed the experiment in four different fish groups: control C; lead � Pb (administration of lead in water 0.075mg/mL of water, as Pb(NO3)2 x � H2O); lead (the same dose) and 2% of freeze-dry garlic incorporated into fishes� food � Pb+garlic; lead (the same dose) and 2% chlorella incorporated into fishes� food � Pb+chlorella, for 21 consecutive days. The iron concentration was analysed with AAS (Atomic Absorption Spectroscopy) from gills, muscle, skin (and scales), intestine, liver, heart, brain, ovary, testicles, and kidney. The obtained data presented a significantly decrease of iron content in all tested tissue samples that demonstrated, alteration of iron homeostasis, explained by a strong antagonistic effect of lead on iron. Our experiment showed that biologic active principles from garlic and chlorella act like natural protectors, and potentiate the iron deficiency even in the case of lead overload in aquatic environment, for fish.

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Current Challenges in the Development of Vaccines and Drugs Against Emerging Vector-borne Diseases

Current Medicinal Chemistry ◽

10.2174/0929867325666181105121146 ◽

2019 ◽

Vol 26 (16) ◽

pp. 2974-2986 ◽

Cited By ~ 4

Author(s):

Kwang-sun Kim

Keyword(s):

New Host ◽

In Vivo Models ◽

Vector Borne Diseases ◽

Novel Drugs ◽

Huge Impact ◽

Tick Borne Disease ◽

Vector Borne ◽

Living Organisms

Vectors are living organisms that transmit infectious diseases from an infected animal to humans or another animal. Biological vectors such as mosquitoes, ticks, and sand flies carry pathogens that multiply within their bodies prior to delivery to a new host. The increased prevalence of Vector-Borne Diseases (VBDs) such as Aedes-borne dengue, Chikungunya (CHIKV), Zika (ZIKV), malaria, Tick-Borne Disease (TBD), and scrub typhus has a huge impact on the health of both humans and livestock worldwide. In particular, zoonotic diseases transmitted by mosquitoes and ticks place a considerable burden on public health. Vaccines, drugs, and vector control methods have been developed to prevent and treat VBDs and have prevented millions of deaths. However, development of such strategies is falling behind the rapid emergence of VBDs. Therefore, a comprehensive approach to fighting VBDs must be considered immediately. In this review, I focus on the challenges posed by emerging outbreaks of VBDs and discuss available drugs and vaccines designed to overcome this burden. Research into promising drugs needs to be upgraded and fast-tracked, and novel drugs or vaccines being tested in in vitro and in vivo models need to be moved into human clinical trials. Active preventive tactics, as well as new and upgraded diagnostics, surveillance, treatments, and vaccination strategies, need to be monitored constantly if we are to manage VBDs of medical importance.

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Real-time observation of tetrapyrrole binding to an engineered bacterial phytochrome

Communications Chemistry ◽

10.1038/s42004-020-00437-3 ◽

2021 ◽

Vol 4 (1) ◽

Author(s):

Yusaku Hontani ◽

Mikhail Baloban ◽

Francisco Velazquez Escobar ◽

Swetta A. Jansen ◽

Daria M. Shcherbakova ◽

...

Keyword(s):

Real Time ◽

Rational Design ◽

Near Infrared ◽

Fluorescent Proteins ◽

Covalent Bond ◽

Binding Pocket ◽

Tissue Imaging ◽

Covalent Attachment ◽

Time Resolved

AbstractNear-infrared fluorescent proteins (NIR FPs) engineered from bacterial phytochromes are widely used for structural and functional deep-tissue imaging in vivo. To fluoresce, NIR FPs covalently bind a chromophore, such as biliverdin IXa tetrapyrrole. The efficiency of biliverdin binding directly affects the fluorescence properties, rendering understanding of its molecular mechanism of major importance. miRFP proteins constitute a family of bright monomeric NIR FPs that comprise a Per-ARNT-Sim (PAS) and cGMP-specific phosphodiesterases - Adenylyl cyclases - FhlA (GAF) domain. Here, we structurally analyze biliverdin binding to miRFPs in real time using time-resolved stimulated Raman spectroscopy and quantum mechanics/molecular mechanics (QM/MM) calculations. Biliverdin undergoes isomerization, localization to its binding pocket, and pyrrolenine nitrogen protonation in <1 min, followed by hydrogen bond rearrangement in ~2 min. The covalent attachment to a cysteine in the GAF domain was detected in 4.3 min and 19 min in miRFP670 and its C20A mutant, respectively. In miRFP670, a second C–S covalent bond formation to a cysteine in the PAS domain occurred in 14 min, providing a rigid tetrapyrrole structure with high brightness. Our findings provide insights for the rational design of NIR FPs and a novel method to assess cofactor binding to light-sensitive proteins.

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Mitochondrial Mistranslation in Brain Provokes a Metabolic Response Which Mitigates the Age-Associated Decline in Mitochondrial Gene Expression

International Journal of Molecular Sciences ◽

10.3390/ijms22052746 ◽

2021 ◽

Vol 22 (5) ◽

pp. 2746

Author(s):

Dimitri Shcherbakov ◽

Reda Juskeviciene ◽

Adrián Cortés Sanchón ◽

Margarita Brilkova ◽

Hubert Rehrauer ◽

...

Keyword(s):

Gene Expression ◽

Metabolic Response ◽

Mitochondrial Gene ◽

Tca Cycle ◽

Brain Mitochondria ◽

Mitochondrial Gene Expression ◽

Rna Seq ◽

The Tca Cycle ◽

Neurological Phenotype

Mitochondrial misreading, conferred by mutation V338Y in mitoribosomal protein Mrps5, in-vivo is associated with a subtle neurological phenotype. Brain mitochondria of homozygous knock-in mutant Mrps5V338Y/V338Y mice show decreased oxygen consumption and reduced ATP levels. Using a combination of unbiased RNA-Seq with untargeted metabolomics, we here demonstrate a concerted response, which alleviates the impaired functionality of OXPHOS complexes in Mrps5 mutant mice. This concerted response mitigates the age-associated decline in mitochondrial gene expression and compensates for impaired respiration by transcriptional upregulation of OXPHOS components together with anaplerotic replenishment of the TCA cycle (pyruvate, 2-ketoglutarate).

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Architecture of RNA influences plant biology

Journal of Experimental Botany ◽

10.1093/jxb/erab030 ◽

2021 ◽

Author(s):

Jiaying Zhu ◽

Changhao Li ◽

Xu Peng ◽

Xiuren Zhang

Keyword(s):

Rna Binding ◽

Rna Binding Proteins ◽

Mirna Biogenesis ◽

Plant Responses ◽

Tertiary Structures ◽

Rna Transcripts ◽

Environmental Variations ◽

Living Organisms ◽

Processing Stability

Abstract The majority of the genome is transcribed to RNA in living organisms. RNA transcripts can form astonishing arrays of secondary and tertiary structures via Watson-Crick, Hoogsteen or wobble base pairing. In vivo, RNA folding is not a simple thermodynamics event of minimizing free energy. Instead, the process is constrained by transcription, RNA binding proteins (RBPs), steric factors and micro-environment. RNA secondary structure (RSS) plays myriad roles in numerous biological processes, such as RNA processing, stability, transportation and translation in prokaryotes and eukaryotes. Emerging evidence has also implicated RSS in RNA trafficking, liquid-liquid phase separation and plant responses to environmental variations such as temperature and salinity. At the molecular level, RSS is correlated with regulating splicing, polyadenylation, protein systhsis, and miRNA biogenesis and functions. In this review, we summarized newly reported methods for probing RSS in vivo and functions and mechanisms of RSS in plant physiology.

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Influence of Oxidative Stress on Time-Resolved Oxygen Detection by [Ru(Phen)3]2+ In Vivo and In Vitro

Molecules ◽

10.3390/molecules26020485 ◽

2021 ◽

Vol 26 (2) ◽

pp. 485

Author(s):

Veronika Huntosova ◽

Denis Horvath ◽

Robert Seliga ◽

Georges Wagnieres

Keyword(s):

Oxidative Stress ◽

Tissue Oxygenation ◽

Intact Cell ◽

Molecular Probes ◽

Stress Factors ◽

Time Resolved ◽

Invasive Approach ◽

Oxygen Detection

Detection of tissue and cell oxygenation is of high importance in fundamental biological and in many medical applications, particularly for monitoring dysfunction in the early stages of cancer. Measurements of the luminescence lifetimes of molecular probes offer a very promising and non-invasive approach to estimate tissue and cell oxygenation in vivo and in vitro. We optimized the evaluation of oxygen detection in vivo by [Ru(Phen)3]2+ in the chicken embryo chorioallantoic membrane model. Its luminescence lifetimes measured in the CAM were analyzed through hierarchical clustering. The detection of the tissue oxygenation at the oxidative stress conditions is still challenging. We applied simultaneous time-resolved recording of the mitochondrial probe MitoTrackerTM OrangeCMTMRos fluorescence and [Ru(Phen)3]2+ phosphorescence imaging in the intact cell without affecting the sensitivities of these molecular probes. [Ru(Phen)3]2+ was demonstrated to be suitable for in vitro detection of oxygen under various stress factors that mimic oxidative stress: other molecular sensors, H2O2, and curcumin-mediated photodynamic therapy in glioma cancer cells. Low phototoxicities of the molecular probes were finally observed. Our study offers a high potential for the application and generalization of tissue oxygenation as an innovative approach based on the similarities between interdependent biological influences. It is particularly suitable for therapeutic approaches targeting metabolic alterations as well as oxygen, glucose, or lipid deprivation.

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A Versatile Setup for Time-Resolved Functional Near Infrared Spectroscopy Based on Fast-Gated Single-Photon Avalanche Diode and on Four-Wave Mixing Laser

Applied Sciences ◽

10.3390/app9112366 ◽

2019 ◽

Vol 9 (11) ◽

pp. 2366 ◽

Cited By ~ 2

Author(s):

Laura Di Sieno ◽

Alberto Dalla Mora ◽

Alessandro Torricelli ◽

Lorenzo Spinelli ◽

Rebecca Re ◽

...

Keyword(s):

Infrared Spectroscopy ◽

Near Infrared Spectroscopy ◽

Near Infrared ◽

Single Photon ◽

Wave Mixing ◽

Functional Near Infrared Spectroscopy ◽

Time Resolved ◽

Diffusive Medium ◽

Spectroscopy System

In this paper, a time-domain fast gated near-infrared spectroscopy system is presented. The system is composed of a fiber-based laser providing two pulsed sources and two fast gated detectors. The system is characterized on phantoms and was tested in vivo, showing how the gating approach can improve the contrast and contrast-to-noise-ratio for detection of absorption perturbation inside a diffusive medium, regardless of source-detector separation.

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