Carbon Nanotubes Induce Metabolomic Profile Disturbances in Zebrafish: NMR-Based Metabolomics Platform

Carbon nanotubes and nanofibers seen as emerging threat to fish: Historical review and trends

Since the discovery of the third allotropic carbon form, carbon-based one-dimensional nanomaterials (1D-CNMs) became an attractive and new technology with different applications that range from electronics to biomedical and environmental technologies. Despite their broad application, data on environmental risks remain limited. Fish are widely used in ecotoxicological studies and biomonitoring programs. Thus, the aim of the current study was to summarize and critically analyze the literature focused on investigating the bioaccumulation and ecotoxicological impacts of 1D-CNMs (carbon nanotubes and nanofibers) on different fish species. In total, 93 articles were summarized and analyzed by taking into consideration the following aspects: bioaccumulation, trophic transfer, genotoxicity, mutagenicity, organ-specific toxicity, oxidative stress, neurotoxicity and behavioral changes. Results have evidenced that the analyzed studies were mainly carried out with multi-walled carbon nanotubes, which were followed by single-walled nanotubes and nanofibers. Zebrafish (Danio rerio) was the main fish species used as model system. CNMs' ecotoxicity in fish depends on their physicochemical features, functionalization, experimental design (e.g. exposure time, concentration, exposure type), as well as on fish species and developmental stage. CNMs' action mechanism and toxicity in fish are associated with oxidative stress, genotoxicity, hepatotoxicity and cardiotoxicity. Overall, fish are a suitable model system to assess the ecotoxicity of, and the environmental risk posed by, CNMs.

Assessment of metabolic responses following silica nanoparticles in zebrafish models using 1H NMR analysis

Silica nanoparticles (SNPs) are widely explored as drug carriers, gene delivery vehicles, and as nanoparticles intended for bone and tissue engineering. SNPs are highly evident through various clinical trials for a wide range of biomedical applications. SNPs are biocompatible and promising nanoparticles for next-generation therapeutics. However, despite the well-established importance of SNPs, metabolomics methods for the SNPs remain elusive which renders its maximal clinical translation. We applied 1H nuclear magnetic resonance (1H NMR) spectroscopy to investigate the metabolomics profile in Zebrafish (Danio rerio) exposed to SNPs. Zebrafish were exposed to the SNPs (10.0, 25.0, and 50.0 μg/mL) for 72 h and whole-body samples were subjected for targeted profiling. Pattern recognition of 1H NMR spectral data depicted alterations in the metabolomic profiles between control and SNPs exposed zebrafish. We found that tryptophane, lysine, methionine, phenylalanine, tyrosine, sn-glycero-3-phosphocholine (G3PC), and o-phosphocholine were decreased. The metabolic expression of niacinamide, nicotinamide adenine dinucleotide (NAD+), citrate, adenosine triphosphate (ATP), and xanthine were increased in zebrafish with SNPs treatment. We are report for the first time on metabolite alterations and phenotypic expression in zebrafish via 1H NMR. These results demonstrate that SNPs can adversely affect the significant metabolic pathways involved in energy, amino acids, cellular membrane, lipids, and fatty acid metabolisms. Metabolomics profiling may be able to detect metabolic dysregulation in SNPs-treated zebrafish and establish a foundation for further toxicological studies.

Current risks of microbial infections in fish and their prevention methods: A review

A fast-expanding sector of agriculture worldwide is aquaculture. The production of fish internationally accounts for around 44 % of the total. Even though the aquaculture environment presents several difficulties, the current development in aquaculture production comes with an increase in infectious diseases, which significantly impacts the production, profitability, and sustainability of the worldwide aquaculture business. Many infectious agents, such as bacteria, viruses, fungi and parasites are causative agents for fish infections. Most infectious diseases found in all types of fish like marine water, freshwater and ornamental fishes are caused by bacteria, with many of them serving as secondary opportunistic invaders that attack sick animals by affecting their natural host immunity. To overcome this, addressing health issues based on methods that have been scientifically verified and advised will help lessen the effects of fish disease. This review aims to highlight some of the common microbial-infecting agents of fish in all types of aquatic systems and their effective methods for preventing infections in aquaculture.

NMR-based metabolomics applied to ecotoxicology with zebrafish (Danio rerio) as a prominent model for metabolic profiling and biomarker discovery: Overviewing the most recent approaches

Metabolomics is an innovative approach used in the medical, toxicological, and biological sciences. As an interdisciplinary topic, metabolomics and its relation with the environment and toxicological research are extensive. The use of substances, such as drugs and pesticides, contributes to the continuous releasing of xenobiotics into the environment, harming organisms and their habitats. In this context, fish are important bioindicators of the environmental condition and have often been used as model species. Among them, zebrafish (Danio rerio) presents itself as a versatile and straightforward option due to its unique attributes for research. Zebrafish proves to be a valuable model for toxicity assays and also for metabolomics profiling by analytical tools. Thus, NMR-based metabolomics associated with statistical analysis can reasonably assist researchers in critical factors related to discovering and validating biomarkers through accurate diagnosis. Therefore, this review aimed to report the studies that applied zebrafish as a model for (eco)toxicological assays and essentially utilized NMR-based metabolomics analysis to assess the biochemical profile and thus suggest the potential biological marker.

Bacterial Pathogenesis in Various Fish Diseases: Recent Advances and Specific Challenges in Vaccine Development

Aquaculture is a fast-growing food sector but is plagued by a plethora of bacterial pathogens that infect fish. The rearing of fish at high population densities in aquaculture facilities makes them highly susceptible to disease outbreaks, which can cause significant economic loss. Thus, immunity development in fish through vaccination against various pathogens of economically important aquaculture species has been extensively studied and has been largely accepted as a reliable method for preventing infections. Vaccination studies in aquaculture systems are strategically associated with the economically and environmentally sustainable management of aquaculture production worldwide. Historically, most licensed fish vaccines have been developed as inactivated pathogens combined with adjuvants and provided via immersion or injection. In comparison, live vaccines can simulate a whole pathogenic illness and elicit a strong immune response, making them better suited for oral or immersion-based therapy methods to control diseases. Advanced approaches in vaccine development involve targeting specific pathogenic components, including the use of recombinant genes and proteins. Vaccines produced using these techniques, some of which are currently commercially available, appear to elicit and promote higher levels of immunity than conventional fish vaccines. These technological advancements are promising for developing sustainable production processes for commercially important aquatic species. In this review, we explore the multitude of studies on fish bacterial pathogens undertaken in the last decade as well as the recent advances in vaccine development for aquaculture.

Microbiome and Metabolomics in Liver Cancer: Scientific Technology

Primary liver cancer is a heterogeneous disease. Liver cancer metabolism includes both the reprogramming of intracellular metabolism to enable cancer cells to proliferate inappropriately and adapt to the tumor microenvironment and fluctuations in regular tissue metabolism. Currently, metabolomics and metabolite profiling in liver cirrhosis, liver cancer, and hepatocellular carcinoma (HCC) have been in the spotlight in terms of cancer diagnosis, monitoring, and therapy. Metabolomics is the global analysis of small molecules, chemicals, and metabolites. Metabolomics technologies can provide critical information about the liver cancer state. Here, we review how liver cirrhosis, liver cancer, and HCC therapies interact with metabolism at the cellular and systemic levels. An overview of liver metabolomics is provided, with a focus on currently available technologies and how they have been used in clinical and translational research. We also list scalable methods, including chemometrics, followed by pathway processing in liver cancer. We conclude that important drivers of metabolomics science and scientific technologies are novel therapeutic tools and liver cancer biomarker analysis.

Metabolomic Signatures in Doxorubicin-Induced Metabolites Characterization, Metabolic Inhibition, and Signaling Pathway Mechanisms in Colon Cancer HCT116 Cells

Doxorubicin (DOX) is a chemotherapeutic agent is used for various cancer cells. To characterize the chemical structural components and metabolic inhibition, we applied a DOX to HCT116 colon cancer cells using an independent metabolites profiling approach. Chemical metabolomics has been involved in the new drug delivery systems. Metabolomics profiling of DOX-applied HCT116 colon cancer cellular metabolisms is rare. We used 1H nuclear magnetic resonance (NMR) spectroscopy in this study to clarify how DOX exposure affected HCT116 colon cancer cells. Metabolomics profiling in HCT116 cells detects 50 metabolites. Tracking metabolites can reveal pathway activities. HCT116 colon cancer cells were evenly treated with different concentrations of DOX for 24 h. The endogenous metabolites were identified by comparison with healthy cells. We found that acetate, glucose, glutamate, glutamine, sn-glycero-3-phosphocholine, valine, methionine, and isoleucine were increased. Metabolic expression of alanine, choline, fumarate, taurine, o-phosphocholine, inosine, lysine, and phenylalanine was decreased in HCT116 cancer cells. The metabolic phenotypic expression is markedly altered during a high dose of DOX. It is the first time that there is a metabolite pool and phenotypic expression in colon cancer cells. Targeting the DOX-metabolite axis may be a novel strategy for improving the curative effect of DOX-based therapy for colon cancer cells. These methods facilitate the routine metabolomic analysis of cancer cells.

Solid-state 1H NMR-based metabolomics assessment of tributylin effects in zebrafish bone

Tributyltin (TBT), an endocrine disruptor is used globally in agribusiness and industries as biocides, heat stabilizers, and in chemical catalysis. It is known for its deleterious effects on bone by negatively impacting the functions of osteoblasts, osteoclasts and mesenchymal stem cells. However, the impact of TBT on the metabolomics profile in bone is not yet studied. Here, we demonstrate alterations in chemical metabolomics profiles measured by solid state ¹H nuclear magnetic resonance (¹H NMR) spectroscopy in zebrafish bone following tributyltin (TBT) treatment. TBT of 0, 100, 200, 300, 400 and 500 μg/L were exposed to zebrafish. From this, zebrafish bone has subjected for further metabolomics profiling. Samples were measured via one-dimensional (1D) solvent -suppressed and T₂- filtered methods with in vivo zebrafish metabolites. A dose dependent alteration in the metabolomics profile was observed and results indicated a disturbed aminoacid metabolism, TCA cycle, and glycolysis. We found a significant alteration in the levels of glutamate, glutamine, glutathione, trimethylamine N-oxide (TMAO), and other metabolites. This investigation hints us the deleterious effects of TBT on zebrafish bone enabling a comprehensive understanding of metabolomics profile and is expected to play a crucial role in understanding the deleterious effects of various endocrine disruptor on bone.

Gut microbiome and metabolic response in non-alcoholic fatty liver disease

Fatty liver disease (FLD) is one of the largest burdens to human health worldwide and is associated with gut microbiome and metabolite stability. Engineered liver tissues have shown promise in restoring liver functions in non-alcoholic FLD (NAFLD), hepatitis and cirrhosis. Fatty liver, largely noted in obesity and hepatic cancer, is highly fatal and has led to a global increase in death rates. It is associated with complex metabolic reprogramming too. A standard approach to therapy in the newly diagnosed setting includes surgery or identification of biomarkers/ metabolites for therapeutic purposes, which ultimately focus on improvement of liver health in patients. As such there are no standard procedures for patient care, but depending on the severity, systemic therapy with either genomic, proteomic or metabolomic profiling form potential options. Better comparisons and study of underlying mechanisms in gut microbiome-based metabolic functions in obesity are urgently required. Today, an emerging field, focusing on metabolomic approaches and metabolic phenotyping, involved in high-throughput identification of metabolome in obesity and gut disorders, is involved in biomarker and metabolite identification. There are supporting technologies and approaches in NAFLD that throw light on the metabolites and gut microbiome, and also on the understanding of the risk factors of obesity along with liver cancer metabolic reaction networks. We discuss the current state of NAFLD metabolites, gut micro-environmental changes, and the further challenges in digital metabolomics profiling. Innovative clinical trial designs, with biomarker-enrichment strategies that are required to improve the outcome of NAFLD in patients are also discussed.

Zebrafish: A Promising Real-Time Model System for Nanotechnology-Mediated Neurospecific Drug Delivery

Delivering drugs to the brain has always remained a challenge for the research community and physicians. The blood-brain barrier (BBB) acts as a major hurdle for delivering drugs to specific parts of the brain and the central nervous system. It is physiologically comprised of complex network of capillaries to protect the brain from any invasive agents or foreign particles. Therefore, there is an absolute need for understanding of the BBB for successful therapeutic interventions. Recent research indicates the strong emergence of zebrafish as a model for assessing the permeability of the BBB, which is highly conserved in its structure and function between the zebrafish and mammals. The zebrafish model system offers a plethora of advantages including easy maintenance, high fecundity and transparency of embryos and larvae. Therefore, it has the potential to be developed as a model for analysing and elucidating the permeability of BBB to novel permeation technologies with neurospecificity. Nanotechnology has now become a focus area within the industrial and research community for delivering drugs to the brain. Nanoparticles are being developed with increased efficiency and accuracy for overcoming the BBB and delivering neurospecific drugs to the brain. The zebrafish stands as an excellent model system to assess nanoparticle biocompatibility and toxicity. Hence, the zebrafish model is indispensable for the discovery or development of novel technologies for neurospecific drug delivery and potential therapies for brain diseases.