In vivo anti-lipidemic and antioxidant potential of collagen peptides obtained from great hammerhead shark skin waste.

The aim of the present study was to evaluate the ability of fish collagen peptides (FCP) derived from the skin of great hammerhead shark (Sphyrna mokarran) in attenuating the high fat diet-alcohol induced hyperlipidemia. The oral supplementation of FCP in high fat diet-alcohol fed experimental rats confirmed the regulation of body weight to normal level. The FCP treated group revealed the efficient lipid lowering ability by enhancing the cholesterol metabolism. Western blot analysis of the lipid metabolic enzymes revealed that the oral-intake of FCP has down-regulated the expression levels of fatty acid synthase and 3-Hydroxy-3-methylglutaryl-CoA reductase (HMGCR). Simultaneously, the expression levels of Lecithin-cholesterol acyltransferase (LCAT) in liver was up-regulated. Histopathology analysis of liver tissues demonstrated that the FCP treated group maintained normal liver parenchyma with moderate inflammatory infiltration, whereas the statin treated group developed centrilobular fibrosis, atrophy of hepatocytes and moderate inflammatory infiltration. Oral dietary supplementation of FCP enhanced the activity levels of both superoxide dismutase and catalase enzymes and, lowered the levels of lipid peroxidation in liver tissues. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13197-021-05118-0.

Anti-ulcerogenic potential of anthocyanin-loaded chitosan nanoparticles against alcohol-HCl induced gastric ulcer in rats.

Chitosan is more prominent in food applications due to its versatile properties. Anthocyanins have gained much research attention due to their multifaceted role in preventing various lifestyle ailments. Encapsulated anthocyanin- loaded chitosan nanoparticles (ACNPs) were prepared by conventional ionotropic gelation method. In the present study, the gastro-protective effect of encapsulated ACNPs was evaluated against absolute ethanol-hydrochloric acid (HCl-Ethanol mixture) induced gastric ulcer in male Wistar rats. The histopathology and microscopic scoring of ulcer data of stomach tissue sections revealed that oral administration of encapsulated ACNPs group can alleviate inflammation of induced-gastric ulcer. Further, the expression of anti-inflammatory cytokines (Interleukin 4, IL-4) and suppression of pro-inflammatory cytokines (Interferon gamma, IFN-γ) confirm the cytoprotective effect of encapsulated ACNPs against HCl-Ethanol induced necrotic damage to mucosal membrane. The results of the present study indicate that the gastro protective action of encapsulated ACNPs ascribable to at least in parts to its anti-inflammatory property.[Formula: see text].

Nanoencapsulation in low-molecular-weight chitosan improves in vivo antioxidant potential of black carrot anthocyanin.

BACKGROUND: Anthocyanins are flavonoids that are potential antioxidant, anti-inflammatory, anti-obesity, and anti-carcinogenic nutraceutical ingredients. However, low chemical stability and low bioavailability limit the use of anthocyanins in food. Nanoencapsulation using biopolymers is a recent successful strategy for stabilization of anthocyanins. This study reports the development, characterization, and antioxidant activity of black carrot anthocyanin-loaded chitosan nanoparticles (ACNPs). RESULTS: The ionic gelation technique yielded the ACNPs. The mean hydrodynamic diameter d and polydispersity index PDI of chitosan nanoparticles and ACNPs were found to be d = 455 nm and PDI = 0.542 respectively for chitosan nanoparticles and d = 274 nm and PDI = 0.376 respectively for ACNPs. The size distribution was bimodal. The surface topography revealed that the ACNPs are spherical and display a coacervate structure. Fourier transform infrared analysis revealed physicochemical interactions of anthocyanins with chitosan. The loading process could achieve an encapsulation efficiency of 70%. The flow behavior index η of encapsulated ACNPs samples revealed Newtonian and shear thickening characteristics. There was a marginal reduction in the in vitro antioxidant potential of anthocyanins after nanoencapsulation, as evidenced from 2,2-diphenyl-1-picrylhydrazyl, ferric reducing antioxidant power, and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) assays. Interestingly, the in vivo antioxidant potential of anthocyanins improved following nanoencapsulation, as observed in the serum antioxidant assays. CONCLUSION: The optimized nanoencapsulation process resulted in spherical nanoparticles with appreciable encapsulation efficiency. The nanoencapsulation process improved the in vivo antioxidant activity of anthocyanins, indicating enhanced stability and bioavailability. The promising antioxidant activity of the ACNPs suggests a potential for utilization as a nutraceutical supplement. © 2021 Society of Chemical Industry.

Fabrication and characterization of multiscale electrospun scaffolds for cartilage regeneration.

Recently, scaffolds for tissue regeneration purposes have been observed to utilize nanoscale features in an effort to reap the cellular benefits of scaffold features resembling extracellular matrix (ECM) components. However, one complication surrounding electrospun nanofibers is limited cellular infiltration. One method to ameliorate this negative effect is by incorporating nanofibers into microfibrous scaffolds. This study shows that it is feasible to fabricate electrospun scaffolds containing two differently scaled fibers interspersed evenly throughout the entire construct as well as scaffolds containing fibers composed of two discrete materials, specifically fibrin and poly(ε-caprolactone). In order to accomplish this, multiscale fibrous scaffolds of different compositions were generated using a dual extrusion electrospinning setup with a rotating mandrel. These scaffolds were then characterized for fiber diameter, porosity and pore size and seeded with human mesenchymal stem cells to assess the influence of scaffold architecture and composition on cellular responses as determined by cellularity, histology and glycosaminoglycan (GAG) content. Analysis revealed that nanofibers within a microfiber mesh function to maintain scaffold cellularity under serum-free conditions as well as aid the deposition of GAGs. This supports the hypothesis that scaffolds with constituents more closely resembling native ECM components may be beneficial for cartilage regeneration.

Rapid dissolution of ZnO nanocrystals in acidic cancer microenvironment leading to preferential apoptosis.

The microenvironment of cancer plays a very critical role in the survival, proliferation and drug resistance of solid tumors. Here, we report an interesting, acidic cancer microenvironment-mediated dissolution-induced preferential toxicity of ZnO nanocrystals (NCs) against cancer cells while leaving primary cells unaffected. Irrespective of the size-scale (5 and 200 nm) and surface chemistry differences (silica, starch or polyethylene glycol coating), ZnO NCs exhibited multiple stress mechanisms against cancer cell lines (IC(50)∼150 µM) while normal human primary cells (human dermal fibroblast, lymphocytes, human umbilical vein endothelial cells) remain less affected. Flow cytometry and confocal microscopy studies revealed that ZnO NCs undergo rapid preferential dissolution in acidic (pH ∼5-6) cancer microenvironment causing elevated ROS stress, mitochondrial superoxide formation, depolarization of mitochondrial membrane, and cell cycle arrest at S/G2 phase leading to apoptosis. In effect, by elucidating the unique toxicity mechanism of ZnO NCs, we show that ZnO NCs can destabilize cancer cells by utilizing its own hostile acidic microenvironment, which is otherwise critical for its survival.