Synthesis and defect characterization of hybrid ceria nanostructures as a possible novel therapeutic material towards COVID-19 mitigation

This study reports the synthesis of hybrid nanostructures composed of cerium dioxide and microcrystalline cellulose prepared by the microwave-assisted hydrothermal route under distinct temperature and pH values. Their structural, morphological and spectroscopic behaviors were investigated by X-Rays Diffraction, Field Emission Gun Scanning Electron Microscopy, High-Resolution Transmission Electron Microscopy, and Fourier-Transform Infrared, Ultraviolet–Visible, Raman and Positron Annihilation Lifetime spectroscopies to evaluate the presence of structural defects and their correlation with the underlying mechanism regarding the biocide activity of the studied material. The samples showed mean crystallite sizes around 10 nm, characterizing the formation of quantum dots unevenly distributed along the cellulose surface with a certain agglomeration degree. The samples presented the characteristic Ce–O vibration close to 450 cm⁻¹ and a second-order mode around 1050 cm⁻¹, which is indicative of distribution of localized energetic levels originated from defective species, essential in the scavenging of reactive oxygen species. Positron spectroscopic studies showed first and second lifetime components ranging between 202–223 ps and 360–373 ps, respectively, revealing the presence of two distinct defective oxygen species, in addition to an increment in the concentration of Ce³⁺-oxygen vacancy associates as a function of temperature. Therefore, we have successfully synthesized hybrid nanoceria structures with potential multifunctional therapeutic properties to be further evaluated against the COVID-19.

Preclinical studies conducted on nanozyme antioxidants: shortcomings and challenges based on US FDA regulations

The wide prevalence of oxidative stress-induced diseases has led to a growing demand for antioxidant therapeutics worldwide. Nanozyme antioxidants are drawing enormous attention as practical alternatives for conventional antioxidants. The considerable body of research over the last decade and the promising results achieved signify the potential of nanozyme antioxidants to secure a place in the expanding market of antioxidant therapeutics. Nonetheless, there is no report on clinical trials for their further evaluation. Through analyzing in-depth selected papers which have conducted in vivo studies on nanozyme antioxidants, this review aims to pinpoint and discuss possible reasons impeding development of research toward clinical studies and to offer some practical solutions for future studies to bridge the gap between preclinical and clinical stages.

Nanoceria as a possible agent for the management of COVID-19

The COVID-19 pandemic has emerged as an unprecedented global healthcare emergency and has devastated the global economy. The SARS-CoV-2 virus replicates in the host cells and is seemingly much more virulent compared to other flu viruses, as well as the SARS-CoV-1. The respiratory complications of the disease include acute respiratory distress syndrome (ARDS), cytokine storm, systemic inflammation, and pulmonary fibrosis. Nanoceria (NC) is a versatile rare earth nanoparticle with remarkable catalase and superoxide dismutase mimetic redox regenerative properties. Interestingly, NC possesses promising anti-inflammatory, antioxidant and anti-fibrotic properties, making it an attractive tool to fight against the SARS-CoV-2 as well as the associated systemic complications. Until now, there is no clinically approved vaccine or drug for the treatment of COVID-19, and the conquest to find a novel therapy for this global havoc is being undertaken at a warlike pace. Herein, based on preclinical evidence, we hypothesize that NC owing to its unique pharmacological properties, might be an attractive preclinical candidate to win the battle over COVID-19. Further, it may be used as a prevention or treatment strategy in combination with other drugs.

Synergistic antioxidant activity of size controllable chitosan-templated Prussian blue nanoparticle

Aim: Prussian blue nanoparticles (PB NPs) have been reported as excellent antioxidant agents owing to their ability to scavenge reactive oxygen species. However, their poor stability in vivo limits their use in biomedical applications. Materials & methods: In this study, we developed chitosan-templated PB NPs using water-soluble chitosan samples with molecular weights ranging from 3 to 100 kDa, which stabilized the PB NPs and improved their antioxidant activity. Results & conclusion: The chitosan-templated PB NPs coordinated with the optimal chitosan molecular weight had uniform sphere-like particles, improved stability and effective scavenging activity of in vitro reactive oxygen species generation in murine fibroblast cells stimulated by oxidative stress agents without any cytotoxicity, implying that they could be promising antioxidant agents.

Zebrafish: an emerging real-time model system to study Alzheimer's disease and neurospecific drug discovery

Zebrafish (Danio rerio) is emerging as an increasingly successful model for translational research on human neurological disorders. In this review, we appraise the high degree of neurological and behavioural resemblance of zebrafish with humans. It is highly validated as a powerful vertebrate model for investigating human neurodegenerative diseases. The neuroanatomic and neurochemical pathways of zebrafish brain exhibit a profound resemblance with the human brain. Physiological, emotional and social behavioural pattern similarities between them have also been well established. Interestingly, zebrafish models have been used successfully to simulate the pathology of Alzheimer’s disease (AD) as well as Tauopathy. Their relatively simple nervous system and the optical transparency of the embryos permit real-time neurological imaging. Here, we further elaborate on the use of recent real-time imaging techniques to obtain vital insights into the neurodegeneration that occurs in AD. Zebrafish is adeptly suitable for Ca²⁺ imaging, which provides a better understanding of neuronal activity and axonal dystrophy in a non-invasive manner. Three-dimensional imaging in zebrafish is a rapidly evolving technique, which allows the visualisation of the whole organism for an elaborate in vivo functional and neurophysiological analysis in disease condition. Suitability to high-throughput screening and similarity with humans makes zebrafish an excellent model for screening neurospecific compounds. Thus, the zebrafish model can be pivotal in bridging the gap from the bench to the bedside. This fish is becoming an increasingly successful model to understand AD with further scope for investigation in neurodevelopment and neurodegeneration, which promises exciting research opportunities in the future.

Zebrafish: A Premier Vertebrate Model for Biomedical Research in Indian Scenario

The zebrafish (Danio rerio) is a versatile model organism that has been used in biomedical research for several decades to study a wide range of biological phenomena. There are many technical advantages of using zebrafish over other vertebrate models. They are readily available, hardy, easy, and inexpensive to maintain in the laboratory, have a short life cycle, and have excellent fecundity. Due to its optical clarity and reproducible capabilities, it has become one of the predominant models of human genetic diseases. Zebrafish research has made rapid strides in the United States and Europe, but in India the field is at an early stage and many researchers still remain unaware of the full research potential of this tiny fish. The zebrafish model system was introduced into India in the early 2000s. Up to now, more than 200 scientific referred articles have been published by Indian researchers. This review gives an overview of the current state of knowledge for zebrafish research in India, with the aim of promoting wider utilization of zebrafish for high level biological studies.

Impact of albumin based approaches in nanomedicine: Imaging, targeting and drug delivery

A major challenge in the field of nanomedicine is to transform laboratory innovations into commercially successful clinical products. In this campaign, a variety of nanoenabled approaches have been designed and investigated for their role in biomedical applications. The advantages associated with the unique structure of albumin imparts it with the ability to interact with variety of molecules, while the functional groups present on their surface provide base for large number of modifications making it as an ideal nanocarrier system. So far, a variety of albumin based nanoenabled approaches have been intensively exploited for effective diagnosis and personalized medicine, among them some have successfully completed their journey from lab bench to marketed products. This review focuses on the recent most promising advancement in the field of albumin based nanoenabled approaches for various biomedical applications and their potential use in cancer diagnosis and therapy.