Improving Polysaccharide-Based Chitin/Chitosan-Aerogel Materials by Learning from Genetics and Molecular Biology

Revolutionizing Cancer Treatment: Biopolymer-Based Aerogels as Smart Platforms for Targeted Drug Delivery

Cancer stands as a leading cause of global mortality, with chemotherapy being a pivotal treatment approach, either alone or in conjunction with other therapies. The primary goal of these therapies is to inhibit the growth of cancer cells specifically, while minimizing harm to healthy dividing cells. Conventional treatments, often causing patient discomfort due to side effects, have led researchers to explore innovative, targeted cancer cell therapies. Thus, biopolymer-based aerogels emerge as innovative platforms, showcasing unique properties that respond intelligently to diverse stimuli. This responsiveness enables precise control over the release of anticancer drugs, enhancing therapeutic outcomes. The significance of these aerogels lies in their ability to offer targeted drug delivery with increased efficacy, biocompatibility, and a high drug payload. In this comprehensive review, the author discuss the role of biopolymer-based aerogels as an emerging functionalized platforms in anticancer drug delivery. The review addresses the unique properties of biopolymer-based aerogels showing their smart behavior in responding to different stimuli including temperature, pH, magnetic and redox potential to control anticancer drug release. Finally, the review discusses the application of different biopolymer-based aerogel in delivering different anticancer drugs and also discusses the potential of these platforms in gene delivery applications.

The biology of insect chitinases and their roles at chitinous cuticles

Chitin is one of the most prevalent biomaterials in the natural world. The chitin matrix formation and turnover involve several enzymes for chitin synthesis, maturation, and degradation. Sequencing of the Drosophila genome more than twenty years ago revealed that insect genomes contain a number of chitinases, but why insects need so many different chitinases was unclear. Here, we focus on insect GH18 family chitinases and discuss their participation in chitin matrix formation and degradation. We describe their variations in terms of temporal and spatial expression patterns, molecular function, and physiological consequences at chitinous cuticles. We further provide insight into the catalytic mechanisms by discussing chitinase protein domain structures, substrate binding, and enzymatic activities with respect to structural analysis of the enzymatic GH18 domain, substrate-binding cleft, and characteristic TIM-barrel structure.

Enhanced immune responses in dexamethasone immunosuppressed male rats supplemented with herbal extracts, chitosan nanoparticles, and their conjugates

Nowadays, the world is challenged with highly contagious diseases, one of their preliminary virulence mechanisms is the suppression of innate immunity. Therefore, promoting natural immunity is a good precautionary strategy. we investigated and compared the effects of several natural herbal extracts -Moringa oleifera, Ziziphus spina christi, and Saussurea costus, and chitosan nanoparticles (CS NPs)- as well as conjugated extracts with CS NPs on the immunological parameters of dexamethasone immunosuppressed (IS) male rats. The plant extracts were assessed for total flavonoids, phenolics, and antioxidant activity. The CS NPs and their conjugates were characterized using particles size, zeta potentials, and Fourier-transform infrared spectroscopy analyses. The chemical analysis of the plant extracts, CS NPs, and their conjugates was performed using energy dispersive X-ray fluorescence, and their cytotoxicity was evaluated in human lung fibroblast (WI-38) and human embryonic kidney (HEK-293) cell lines. For in vivo evaluations, 72 adult male rats were divided into 9 groups: control, IS, three plant extracts, CS, and conjugates of the three plant extracts and CS NPs. Oral supplementation (day after day) lasted for 28 days. Liver, kidney, and spleen tissue samples were collected for histopathology and Ki-67 expression analyses. The results revealed that the plant extracts and CS improved the total leukocyte counts, complement 3, complement 4, interferon-gamma, and tumor necrosis factor levels at day 28. However, the plant extract-CS NPs conjugates faster and have higher immunostimulatory effects at day 14. Furthermore, the atrophied white pulp of the spleen induced by dexamethasone was alleviated, and Ki-67 expression was elevated in all the treated groups. Conclusively, the conjugates of Moringa oleifera, Ziziphus spina christi, and Saussurea costus extract with CS NPs demonstrated more potent and rapid immune responses at lower doses and concentrations compared to the plant extracts or CS NPs alone, without causing liver or kidney injuries. Thus, supplementation of these conjugated plant extracts at lower doses and concentrations is recommended to improve immunity while considering safety considerations.

Recent progressions in biomedical and pharmaceutical applications of chitosan nanoparticles: A comprehensive review

Nowadays, the most common approaches in the prognosis, diagnosis, and treatment of diseases are along with undeniable limitations. Thus, the ever-increasing need for using biocompatible natural materials and novel practical modalities is required. Applying biomaterials, such as chitosan nanoparticles (CS NPs: FDA-approved long-chain polymer of N-acetyl-glucosamine and D-glucosamine for some pharmaceutical applications), can serve as an appropriate alternative to overcome these limitations. Recently, the biomedical applications of CS NPs have extensively been investigated. These NPs and their derivatives can not only prepare through different physical and chemical approaches but also modify with various molecules and bioactive materials. The potential properties of CS NPs, such as biocompatibility, biodegradability, serum stability, solubility, non-immunogenicity, anti-inflammatory properties, appropriate pharmacokinetics and pharmacodynamics, and so forth, have made them excellent candidates for biomedical applications. Therefore, CS NPs have efficiently applied for various biomedical applications, like regenerative medicine and tissue engineering, biosensors for the detection of microorganisms, and drug delivery systems (DDS) for the suppression of diseases. These NPs possess a high level of biosafety. In summary, CS NPs have the potential ability for biomedical and clinical applications, and it would be remarkably beneficial to develop new generations of CS-based material for the future of medicine.

A dynamic interplay between chitin synthase and the proteins Expansion/Rebuf reveals that chitin polymerisation and translocation are uncoupled in Drosophila

Chitin is a highly abundant polymer in nature and a principal component of apical extracellular matrices in insects. In addition, chitin has proved to be an excellent biomaterial with multiple applications. In spite of its importance, the molecular mechanisms of chitin biosynthesis and chitin structural diversity are not fully elucidated yet. To investigate these issues, we use Drosophila as a model. We previously showed that chitin deposition in ectodermal tissues requires the concomitant activities of the chitin synthase enzyme Kkv and the functionally interchangeable proteins Exp and Reb. Exp/Reb are conserved proteins, but their mechanism of activity during chitin deposition has not been elucidated yet. Here, we carry out a cellular and molecular analysis of chitin deposition, and we show that chitin polymerisation and chitin translocation to the extracellular space are uncoupled. We find that Kkv activity in chitin translocation, but not in polymerisation, requires the activity of Exp/Reb, and in particular of its conserved Nα-MH2 domain. The activity of Kkv in chitin polymerisation and translocation correlate with Kkv subcellular localisation, and in absence of Kkv-mediated extracellular chitin deposition, chitin accumulates intracellularly as membrane-less punctae. Unexpectedly, we find that although Kkv and Exp/Reb display largely complementary patterns at the apical domain, Exp/Reb activity nonetheless regulates the topological distribution of Kkv at the apical membrane. We propose a model in which Exp/Reb regulate the organisation of Kkv complexes at the apical membrane, which, in turn, regulates the function of Kkv in extracellular chitin translocation.

Recent progress and future directions of membranes green polymers for oily wastewater treatment

The preparation, modification and application of green polymers such as poly-lactic acid (PLA), chitosan (CS), and cellulose acetate (CA) for oily wastewater treatment is summed up in this review. Due to the low environmental pollution, good chemical resistivity, high hydrophobicity, and good capacity for water-oil emulsion separation of the presented polymers, it then highlights the various membrane production methods and their role in producing effective membranes, with a focus on recent advances in improving membrane properties through the addition of various Nano materials. As a result, the hydrophilic/hydrophobic properties that are critical in the oil separation mechanism are highlighted. Finally, it looks at the predictions and challenges in oil/water separation and recovery. These ideas are discussed with a focus on modern production methods and oil separation proficiency.

Bioinspired Hydrogels as Platforms for Life-Science Applications: Challenges and Opportunities

Hydrogels, as interconnected networks (polymer mesh; physically, chemically, or dynamic crosslinked networks) incorporating a high amount of water, present structural characteristics similar to soft natural tissue. They enable the diffusion of different molecules (ions, drugs, and grow factors) and have the ability to take over the action of external factors. Their nature provides a wide variety of raw materials and inspiration for functional soft matter obtained by complex mechanisms and hierarchical self-assembly. Over the last decade, many studies focused on developing innovative and high-performance materials, with new or improved functions, by mimicking biological structures at different length scales. Hydrogels with natural or synthetic origin can be engineered as bulk materials, micro- or nanoparticles, patches, membranes, supramolecular pathways, bio-inks, etc. The specific features of hydrogels make them suitable for a wide variety of applications, including tissue engineering scaffolds (repair/regeneration), wound healing, drug delivery carriers, bio-inks, soft robotics, sensors, actuators, catalysis, food safety, and hygiene products. This review is focused on recent advances in the field of bioinspired hydrogels that can serve as platforms for life-science applications. A brief outlook on the actual trends and future directions is also presented.

The Use of Chitosan-Coated Nanovesicles in Repairing Alcohol-Induced Damage of Liver Cells in Mice

Background and Objectives In the past few decades, the studies concerning the natural polysaccharide chitosan have been centered on a new direction: its hepatoprotective action. The aim of our study was to evaluate the influence of previously designed chitosan lipid vesicles on the liver damage induced by alcohol consumption in mice. Materials and Methods The study involved the oral administration of substances in one daily dose as follows: Group 1 (control): water; Group 2 (control alcohol): 5% alcohol in water; Group 3 (CHIT): 0.1 mL/10 g body weight chitosan solution in animals treated with alcohol; Group 4 (CHIT-ves): 0.1 mL/10 g body chitosan vesicles in animals treated with alcohol; Group 5 (AcA): 200 mg/kg body ascorbic acid in animals treated with alcohol. In order to evaluate liver damage after alcohol consumption, the following hematological parameters were tested: the activity of alanine aminotransferase, aspartate aminotransferase and lactate dehydrogenase; serum values of urea and creatinine; the phagocytic capacity of polymorphonuclear neutrophilsin peripheral blood;serum opsonic capacity;bactericidal capacity of peritoneal macrophages; and the activity of malondialdehyde, glutathione peroxidase, superoxide dismutase and lactate dehydrogenase. Results and Conclusions The treatment with chitosan vesicles decreased liver enzyme activity and reduced the oxidative stress disturbances in alcoholic mice, thus repairing the hepatic functional and structural damages. These beneficial activities of chitosan vesicles were comparable with ascorbic acid effects in alcoholic mice.