α-Chitosan and β-Oligochitosan Mixtures-Based Formula for In Vitro Assessment of Melanocyte Cells Response

Chitosan is a natural polymer with numerous biomedical applications. The cellular activity of chitosan has been studied in various types of cancer, including melanoma, and indicates that these molecules can open new perspectives on antiproliferative action and anticancer therapy. This study analyzes how different chitosan conformations, such as α-chitosan (CH) or β-oligochitosan (CO), with various degrees of deacetylation (DDA) and molar mass (MM), both in different concentrations and in CH-CO mixtures, influence the cellular processes of SK-MEL-28 melanocytes, to estimate the reactivity of these cells to the applied treatments. The in vitro evaluation was carried out, aiming at the cellular metabolism (MTT assay), cellular morphology, and chitinase-like glycoprotein YKL-40 expression. The in vitro effect of the CH-CO mixture application on melanocytes is obvious at low concentrations of α-chitosan/β-oligochitosan (1:2 ratio), with the cell's response supporting the hypothesis that β-oligo-chitosan amplifies the effect. This oligochitosan mixture, favored by the β conformation and its small size, penetrates faster into the cells, being more reactive when interacting with some cellular components. Morphological effects expressed by the loss of cell adhesion and the depletion of YKL-40 synthesis are significant responses of melanocytes. β-oligochitosan (1.5 kDa) induces an extension of cytophysiological effects and limits the cell viability compared to α-chitosan (400-900 kDa). Statistical analysis using multivariate techniques showed differences between the CH samples and CH-CO mixtures.

Chitooligosaccharide and Its Derivatives: Potential Candidates as Food Additives and Bioactive Components

Chitooligosaccharide (CHOS), a depolymerized chitosan, can be prepared via physical, chemical, and enzymatic hydrolysis, or a combination of these techniques. The superior properties of CHOS have attracted attention as alternative additives or bioactive compounds for various food and biomedical applications. To increase the bioactivities of a CHOS, its derivatives have been prepared via different methods and were characterized using various analytical methods including FTIR and NMR spectroscopy. CHOS derivatives such as carboxylated CHOS, quaternized CHOS, and others showed their potential as potent anti-inflammatory, anti-obesity, neuroprotective, and anti-cancer agents, which could further be used for human health benefits. Moreover, enhanced antibacterial and antioxidant bioactivities, especially for a CHOS-polyphenol conjugate, could play a profound role in shelf-life extension and the safety assurance of perishable foods via the inhibition of spoilage microorganisms and pathogens and lipid oxidation. Also, the effectiveness of CHOS derivatives for shelf-life extension can be augmented when used in combination with other preservative technologies. Therefore, this review provides an overview of the production of a CHOS and its derivatives, as well as their potential applications in food as either additives or nutraceuticals. Furthermore, it revisits recent advancements in translational research and in vivo studies on CHOS and its derivatives in the medical-related field.

Proteome Analysis of the Antiproliferative Activity of the Novel Chitooligosaccharide-Gallic Acid Conjugate against the SW620 Colon Cancer Cell Line

Chitooligosaccharide (COS) and gallic acid (GA) are natural compounds with anti-cancer properties, and their conjugate (COS-GA) has several biological activities. Herein, the anti-cancer activity of COS-GA in SW620 colon cancer cells was investigated. MTT assay was used to evaluate cell viability after treatment with 62.5, 122, and 250 µg/mL of COS, GA, and COS-GA for 24 and 48 h. The number of apoptotic cells was determined using flow cytometry. Proteomic analysis was used to explore the mechanisms of action of different compounds. COS-GA and GA showed a stronger anti-cancer effect than COS by reducing SW620 cell proliferation at 125 and 250 µg/mL within 24 h. Flow cytometry revealed 20% apoptosis after COS-GA treatment for 24 h. Thus, GA majorly contributed to the enhanced anti-cancer activity of COS via conjugation. Proteomic analysis revealed alterations in protein translation and DNA duplication in the COS group and the structural constituents of the cytoskeleton, intermediate filament organization, the mitochondrial nucleoid, and glycolytic processes in the COS-GA group. Anti-cancer-activity-related proteins were altered, including CLTA, HSPA9, HIST2H2BF, KRT18, HINT1, DSP, and VIM. Overall, the COS-GA conjugate can serve as a potential anti-cancer agent for the safe and effective treatment of colon cancer.

Determination of Common microRNA Biomarker Candidates in Stage IV Melanoma Patients and a Human Melanoma Cell Line: A Potential Anti-Melanoma Agent Screening Model

MicroRNAs (miRNAs) are small, non-coding RNAs that play an important role in regulating gene expression. Dysregulation of miRNA expression is commonly observed in cancer, and it can contribute to malignant cell growth. Melanoma is the most fatal type of skin malignant neoplasia. Some microRNAs can be prospective biomarkers for melanoma in stage IV (advanced) at higher risk of relapses and require validation for diagnostic purposes. This work aimed to (1) determine the most significant microRNA biomarker candidates in melanoma using content analysis of the scientific literature, (2) to show microRNA biomarker candidates' diagnostic efficacy between melanoma patients and healthy control groups in a small-scale preliminary study by blood plasma PCR analysis, (3) to determine significant microRNA markers of the MelCher human melanoma cell line, which are also detected in patients with melanoma, that can be used as markers of drug anti-melanoma activity, and (4) test anti-melanoma activity of humic substances and chitosan by their ability to reduce level of marker microRNAs. The content analysis of the scientific literature showed that hsa-miR-149-3p, hsa-miR-150-5p, hsa-miR-193a-3p, hsa-miR-21-5p, and hsa-miR-155-5p are promising microRNA biomarker candidates for diagnosing melanoma. Estimating microRNA in plasma samples showed that hsa-miR-150-5p and hsa-miR-155-5p may have a diagnostic value for melanoma in stage IV (advanced). When comparing ΔCt hsa-miR-150-5p and ΔCt hsa-miR-155-5p levels in melanoma patients and healthy donors, statistically significant differences were found (p = 0.001 and p = 0.001 respectively). Rates ΔCt were significantly higher among melanoma patients (medians concerning the reference gene miR-320a were 1.63 (1.435; 2.975) and 6.345 (4.45; 6.98), respectively). Therefore, they persist only in plasma from the melanoma patients group but not in the healthy donors group. In human wild-type stage IV melanoma (MelCher) cell culture, the presence of hsa-miR-150-5p and hsa-miR-155-5p in supernatant was detected. The ability of humic substance fractions and chitosan to reduce levels of hsa-miR-150-5p and hsa-miR-155-5p was tested on MelCher cultures, which is associated with anti-melanoma activity. It was found that the hymatomelanic acid (HMA) fraction and its subfraction UPLC-HMA statistically significantly reduced the expression of miR-150-5p and miR-155-5p (p ≤ 0.05). For the humic acid (HA) fraction, this activity was determined only to reduce miR-155-5p (p ≤ 0.05). Ability to reduce miR-150-5p and miR-155-5p expression on MelCher cultures was not determined for chitosan fractions with a molecular weight of 10 kDa, 120 kDa, or 500 kDa. Anti-melanoma activity was also determined in the MTT test on MelCher cultures for explored substances. The median toxic concentration (TC50) was determined for HA, HMA and UPLC-HMA (39.3, 39.7 and 52.0 μg/mL, respectively). For 10 kDa, 120 kDa, or 500 kDa chitosan fractions TC50 was much higher compared to humic substances (508.9, 6615.9, 11352.3 μg/mL, respectively). Thus, our pilot study identified significant microRNAs for testing the in vitro anti-melanoma activity of promising drugs and melanoma diagnostics in patients. Using human melanoma cell cultures gives opportunities to test new drugs on a culture that has a microRNA profile similar to that of patients with melanoma, unlike, for example, murine melanoma cell cultures. It is necessary to conduct further studies with a large number of volunteers, which will make it possible to correlate the profile of individual microRNAs with specific patient data, including the correlation of the microRNA profile with the stage of melanoma.

Potential Medical Applications of Chitooligosaccharides

Chitooligosaccharides, also known as chitosan oligomers or chitooligomers, are made up of chitosan with a degree of polymerization (DP) that is less than 20 and an average molecular weight (MW) that is lower than 3.9 kDa. COS can be produced through enzymatic conversions using chitinases, physical and chemical applications, or a combination of these strategies. COS is of significant interest for pharmacological and medical applications due to its increased water solubility and non-toxicity, with a wide range of bioactivities, including antibacterial, anti-inflammatory, anti-obesity, neuroprotective, anticancer, and antioxidant effects. This review aims to outline the recent advances and potential applications of COS in various diseases and conditions based on the available literature, mainly from preclinical research. The prospects of further in vivo studies and translational research on COS in the medical field are highlighted.

Fabrication of a multi-level drug release platform with liposomes, chitooligosaccharides, phospholipids and injectable chitosan hydrogel to enhance anti-tumor effectiveness

Some anti-cancer drugs have poor solubility and availability, and are easily eliminated by rapid metabolism in vivo. To fix the drugs at the administration site and delay their release, a release platform with multi-level and multi-function was designed. The results showed that the curcumin (Cur) loaded liposomes (Cur@Lip) were coated sequentially with positive Chitooligosaccharides (Cur@Lip-Cos) and negative phospholipids (Cur@Lip-Cos-PC), to enhance water solubility, encapsulation efficiency, and delayed the release of the Cur, stability and cell intake of the liposomes, and the bioactivity of the system. The Cur@Lip-Cos could significantly enhance the inhibitory effect of MCF-7, better than the Cur@Lip-Cos-PC. The Lips were then fixed in an injectable thiolated chitosan hydrogel for local immobilization and sustained release which can effectively delay the release of Cur to inhibit MCF-7 growth. In summary, the innovative and biomimetic liposomal hydrogels are expected to provide more ideas for the design of drug carriers.

The impact of chitooligosaccharides and their derivatives on the in vitro and in vivo antitumor activity: A comprehensive review

Chitooligosaccharides (COS) are the degraded products of chitin or chitosan. COS is water-soluble, non-cytotoxic to organisms, readily absorbed through the intestine, and eliminated primarily through the kidneys. COS possess a wide range of biological activities, including immunomodulation, cholesterol-lowering, and antitumor activity. Although work on COS goes back at least forty years, several aspects remain unclear. This review narrates the recent developments in COS antitumor activities, while paying considerable attention to the impacts of physicochemical properties (such as molecular weight and degrees of deacetylation) and chemical modifications both in vitro and in vivo. COS derivatives not only improve some physicochemical properties, but also expand the range of applications in drug and gene delivery. COS (itself or as a drug carrier) can inhibit tumor cell proliferation and metastasis, which might be attributed to its ability to stimulate the immune response along with its anti-angiogenic activity. Further, an attempt has been made to report limitations and future research. The potential health benefits of COS and its derivatives against cancer may offer a new insight on their applications in food and medical fields.

The purification of pectin from commercial fruit flours results in a jaboticaba fraction that inhibits galectin-3 and colon cancer cell growth

Fruits are a prime source of nutrients, bioactive compounds, and dietary fibers. Some products available on the Brazilian market use fruit by-products and claim to have useful effects on human health due to their dietary fiber content. The study aimed to extract and purify the total (28-47 w/w yield) and soluble dietary fiber (4-7 w/w yield) from jaboticaba, papaya, and plum commercial flours sold in Brazil and to study the in vitro biological effects of the fractions. The purified water-soluble fractions consisted mainly of pectin-derived oligosaccharides (5-15 KDa molecular weight) with a negligible content of polyphenols, protein, ashes, and starch. Jaboticaba sample was 95% galacturonic acid while plum and papaya samples were 40% galacturonic acid and 40% galactose (mol%), approximately. The samples were tested for recombinant human galectin-3 inhibition and changes in the cell viability of human colorectal cancer cells. Only the jaboticaba sample inhibited galectin-3 and decreased HCT116 cell viability after 48 h of treatment (p ≤ 0.01) while the plum sample decreased the cell viability after 24 h treatment (p ≤ 0.05). The results obtained in this study demonstrate the relationship between the structure of the soluble fibers extracted from jaboticaba flour and the possible beneficial effects of their consumption.

Research Advances in Chitosan Oligosaccharides: From Multiple Biological Activities to Clinical Applications

Chitosan oligosaccharides (COS), hydrolysed products of chitosan, are low-molecular weight polymers with a positive charge and good biocompatibility. COS have recently been reported to possess various biological activities, including hypoglycaemic, hypolipidaemic, antioxidantantioxidant, immune regulation, anti-inflammatory, antitumour, antibacterial, and tissue engineering activities, exhibiting extensive application prospects. Currently, the biological processes and mechanisms of COS are attractive topics of study, ranging from the genetic, molecular and protein levels. This article reviews the recent discoveries about COS, especially in metabolic regulation, immune function and tissue repair, providing important insights into their multiple biological activities, medical benefits, and therapeutic mechanisms.

Crosstalk between chitosan and cell signaling pathways

The field of tissue engineering (TE) experiences its most exciting time in the current decade. Recent progresses in TE have made it able to translate into clinical applications. To regenerate damaged tissues, TE uses biomaterial scaffolds to prepare a suitable backbone for tissue regeneration. It is well proven that the cell-biomaterial crosstalk impacts tremendously on cell biological activities such as differentiation, proliferation, migration, and others. Clarification of exact biological effects and mechanisms of a certain material on various cell types promises to have a profound impact on clinical applications of TE. Chitosan (CS) is one of the most commonly used biomaterials with many promising characteristics such as biocompatibility, antibacterial activity, biodegradability, and others. In this review, we discuss crosstalk between CS and various cell types to provide a roadmap for more effective applications of this polymer for future uses in tissue engineering and regenerative medicine.

Chitosan Oligosaccharides Induce Apoptosis in Human Renal Carcinoma via Reactive-Oxygen-Species-Dependent Endoplasmic Reticulum Stress

In recent years, various studies have confirmed the role of natural products as effective cancer prevention and treatment drugs. The present study demonstrated that chitosan oligosaccharide (COS) from shells of shrimp and crab caused an inhibitory effect on the proliferation of human renal carcinoma in vitro and in vivo. First, the in vivo biodistribution of COS was investigated by the synthesis of cyanine-7-labeled COS (COS-Cy7) following tail vein injection. The kidney was found to be a major target organ. Then, the impacts on renal carcinoma cell proliferation, apoptosis, and reactive oxygen species (ROS) production were observed in vitro, and an orthotopic xenograft tumor model was designed to evaluate the antitumor efficacy of COS in vivo. In renal carcinoma cells, COS induced G2/M phase arrest and apoptosis in a ROS-dependent fashion. COS significantly promoted mRNA expression of nuclear factor erythroid 2-related factor (Nrf2) and Nrf2 target genes, such as heme oxygenase 1, modifier subunit of glutamate cysteine ligase, and solute carrier family 7 member 11. Additionally, COS significantly upregulated the protein expression of glucose-regulated protein 78, protein RNA-like endoplasmic reticulum (ER) kinase, eukaryotic initiation factor 2α, activating transcription factor 4, C/EBP homologous protein, and cytochrome c, which justified the activation of the ER stress signaling pathway. In vivo, COS repressed tumor growth and induced apoptosis and ROS accumulation, consistent with the in vitro results. Taken together, COS repressed human renal carcinoma growth and induced apoptosis both in vitro and in vivo, mainly via ROS-dependent ER stress pathways.

Protective Effect of Chitosan Oligosaccharides Against Cyclophosphamide-Induced Immunosuppression and Irradiation Injury in Mice

Chitosan oligosaccharides (COS), hydrolyzed products of chitosan, was found to display various biological activities. Herein, we assessed the immunostimulatory activity of COS both in in vitro and in vivo studies. In vitro cytotoxicity studies to murine macrophage RAW264.7 revealed that COS is safe even at the maximum tested concentration of 1000 μg/mL. It also stimulates the production of nitric oxide (NO) and tumor necrosis factor (TNF-α) and enhances the phagocytosis in COS-stimulated RAW264.7. We have shown that the COS could significantly (P < 0.05) restore the reduced immune organs indices, phagocytic index, lymphocyte proliferation, natural killer cell activity, and antioxidant enzyme activities in a cyclophosphamide-induced immunosuppressed mice model. COS can also improve the survival rate in irradiation injury mice and significantly (P < 0.05) increased the spleen indices and up-regulates the CD4+/CD8+ ratio in splenocytes. In sum, the aforementioned results suggest that COS might has the potential to be used as an immunostimulatory agent in patients with immune dysfunctions or be a model for functional food development.

PRACTICAL APPLICATION

COS might has the potential to be used as an immunostimulatory agent in patients with immune dysfunctions or be a model for functional food development.

Chitin and chitosan: biopolymers for wound management

Chitin and chitosan are biopolymers with excellent bioactive properties, such as biodegradability, non-toxicity, biocompatibility, haemostatic activity and antimicrobial activity. A wide variety of biomedical applications for chitin and chitin derivatives have been reported, including wound-healing applications. They are reported to promote rapid dermal regeneration and accelerate wound healing. A number of dressing materials based on chitin and chitosan have been developed for the treatment of wounds. Chitin and chitosan with beneficial intrinsic properties and high potential for wound healing are attractive biopolymers for wound management. This review presents an overview of properties, biomedical applications and the role of these biopolymers in wound care.