Nanoparticle-Based Phototriggered Cancer Immunotherapy and Its Domino Effect in the Tumor Microenvironment.

Immune system evasion by cancer cells is one of the hallmarks of cancers, and it occurs with the support of tumor-associated immune cells (TICs) in the tumor microenvironment that increase the growth and invasiveness of tumor cells. With recent advancements in the development of novel near-infrared (NIR)-responsive nanoparticles, specifically eradicating TICs or inducing an inflammatory immune response by activating killer T cells has become possible. This review will discuss the mechanisms and applications of phototriggered immunotherapy in detail. In addition, various nanoparticles employed in phototriggered immunotherapy for cancer treatment will be covered. Furthermore, the challenges and future directions of phototriggered nanoparticle development for anticancer immunotherapy will be briefly discussed.

Physico-chemical modifications of conjugated linoleic acid for ruminal protection and oxidative stability.

Conjugated linoleic acid (CLA) is a mixture of positional and geometric isomers of octadecadienoic acid [linoleic acid (LA), 18:2n-6]. Although ruminant milk and meat products represent the largest natural source of CLA and therefore, their concentration in ruminant lipids are of interest to human health, chemical or physical modifications of CLA should be needed as a means to enhance oxidative stability, to improve post-ruminal bioavailability, and to increase the clinical application. In fact, CLA are rapidly decomposed to form furan fatty acids when its are oxidized in air, and the effectiveness of dietary supplements of CLA may be related to the extent that their metabolisms by rumen bacteria are avoided. For these reasons, many scientists have examined the effect of manufacturing and protection on the stability of CLA in ruminants and food products. In this review, physico-chemical modifications of CLA for ruminal protection such as calcium salt (Ca), formaldehyde protection (FP), lipid encapsulation (LE), and amide linkage (AL), and for oxidative stability such as green tea catechin (GTC), cyclodextrin (CD), arginine (Arg), amylase, and PEGylation are proposed.

Rumen bypass and biodistribution of l-carnitine from dual-layered coated pellets in cows, in vitro and in vivo.

A ruman bypass delivery system was investigated to improve the delivery efficiency of L-carnitine in biological samples of cows. Highly water-soluble L-carnitine used for dietary supplement in ruminants was chosen. L-Carnitine-loaded compact pellets were prepared by extrusion method and then coated with various coating materials such as ethylcellulose (EC), Eudragit E100 (E100), Eudragit RS100 (RS100), stearyl alcohol and glyceryl monostearate, for single-layered coated pellets (SCP). Two types of dual-layered coated pellets (DCP) were also designed as DCP-A (inner E100/outer EC) or DCP-B (inner EC/outer E100). Preparation of compact pellet and methods of polymeric coatings are the most important strategies for modulated release and rumen bypass efficiency based on chewing behaviors and physiology of veterinary species. DCPs were more efficient in retarding L-carnitine release in rumen fluid (pH 6.8) than the SCP but DCP-B gave much faster release in abomasums fluid (pH 1.2). Both DCP-A and DCP-B showed high in vivo rumen bypass efficiency in cows compared with the nonprotected preparation and most of l-carnitine was readily absorbed. DCP-B was also efficient for delivering L-carnitine in biological samples of cows, mainly in muscle but no statistical differences were observed among the tested preparations after the multiple oral feeding to cows for 3 months. Interestingly, DCP-B produced higher L-carnitine levels in milk in a dose-dependent manner. However, delivery efficiency of L-carnitine preparations in biological samples of cows would rather be more dependent on feeding schedules.

Proposed mechanisms of (-)-epigallocatechin-3-gallate for anti-obesity.

Green tea catechins (GTCs) are polyphenolic flavonoids formerly called vitamin P. GTCs, especially (-)-epigallocatechin-3-gallate (EGCG), lower the incidence of cancers, collagen-induced arthritis, oxidative stress-induced neurodegenerative diseases, and streptozotocin-induced diabetes. Also, inhibition of adipogenesis by green tea and green tea extract has been demonstrated in cell lines, animal models, and humans. The obesity-preventive effects of green tea and its main constituent EGCG are widely supported by results from epidemiological, cell culture, animal, and clinical studies in the last decade. Studies with adipocyte cell lines and animal models have demonstrated that EGCG inhibits extracellular signal-related kinases (ERK), activates AMP-activated protein kinase (AMPK), modulates adipocyte marker proteins, and down-regulates lipogenic enzymes as well as other potential targets. Also, the catechin components of green tea have been shown to possess anti-carcinogenic properties possibly related to their anti-oxidant activity. In addition, it was shown that dietary supplementation with EGCG could potentially contribute to nutritional strategies for the prevention and treatment of type 2 diabetes mellitus. In this review, the biological activities and multiple mechanisms of EGCG in cell lines, animal models, and clinical observations are explained.

Release of albumin from chitosan-coated pectin beads in vitro.

The release behavior of albumin from chitosan-coated pectin beads in vitro was investigated. The factors, such as concentration of CaCl(2), molecular weight of chitosan, pH of chitosan solution, and pH of release medium, which can have a significant effect on the release behavior from the beads, were discussed in this study. The loading efficiency (LE) of albumin showed maximum value when the concentration of CaCl(2) and the weight ratio of pectin to albumin were 2 wt.% and 2, respectively. The release of albumin from pectin beads could be retarded by coating with chitosan at various pH medium. The increase of the concentration of CaCl(2) induced the decrease of albumin release for uncoated-pectin beads, but not much difference of release for coated-pectin ones. The higher molecular weight of chitosan showed less albumin release than the lower one. The release of albumin from the chitosan-coated pectin beads was dependent on pH of coating solution and release medium, which might affect the degree of swelling of pectin beads.