Characterization of the novel chemically modified fungal polysaccharides as the macrophage stimulators

Carboxymethylation of polysaccharides: Synthesis and bioactivities

Polysaccharides are a structurally diverse class of biomolecules with a wide variety of bioactivities. Natural polysaccharides isolated from plants and fungi are used as raw materials in food and pharmaceutical industries due to their therapeutic properties, non-toxicity, and negligible side effects, but many natural polysaccharides possess low bioactivities when compared to synthetic medicines due to their structure and physicochemical properties. Literature studies revealed that carboxymethylation of polysaccharides enhances the bioactivities and water solubility of native polysaccharides significantly, and provide structural diversity and even the addition of new bioactivities. This review article mainly focuses on the recent research on carboxymethylation of polysaccharides including preparation, characterization, and bioactivities. This article also throws light on future directions and scope to develop new carboxymethylated polysaccharide derivatives for many industries such as food processing, cosmetics, nutraceuticals, and pharmaceutical industry.

One-Step Formation of Chondrocytes through Direct Reprogramming via Polysaccharide-Based Gene Delivery

An innovative strategy for the generation of chondrocytes was thoroughly studied in this paper. Polyetherimide-modified polysaccharides of Porphyra yezoensis (pmPPY) served as a nonviral gene vector and delivered Sox9 plasmid to directly reprogram mouse embryonic fibroblasts into chondrocytes. The gene transfer efficiency was evaluated through ELISA, RT-PCR, and Western blot. The induced chondrocytes were identified through toluidine blue, Safranin O, and the immunostaining. The expression level of collagen II was finally evaluated through western blot. The pSox9/pmPPY nanoparticles (1:50) showed lower cytotoxicity as well as greater gene transfection efficiency than Lipofectamine 2000 and polyetherimide (PEI) (p<0.05). The results of toluidine blue, Safranin O, and the immunostaining of collagen II further showed that the normal MEFs were successfully reprogrammed into chondrocytes. These findings indicate that pmPPY could be a promising gene vector for the generation of chondrocytes via single-gene delivery strategy, which might provide abundant chondrocytes for cartilage repair.

Transfection efficiency and internalization of the gene carrier prepared from a triple-helical β-glucan and polydeoxyadenylic acid in macrophage RAW264.7 cells

The stability and gene transfection efficiency of poly(dA)–s-LNT complexes strongly depend on the base length of poly(dA) in the target DNA sequence.

Effect of molecular size and modification pattern on the internalization of water soluble β-(1 → 3)-(1 → 4)-glucan by primary murine macrophages

It has been shown that -(1→3)-(1→4)-glucans (BG34) from barley and oats can trigger recognition and internalization by murine and human macrophages. Increasing evidence has suggested that macrophage recognition and internalization of BG34 are dramatically affected by the purity of BG34, the molecular weight and chemical modification. In this study, we investigated the structural features of BG34 for macrophage recognition and internalization. We prepared homogeneous BG34s of 10 kDa (BG34-10),200 kDa (BG34-200) and 500 kDa (BG34-500) with high purity, and then introduced green fluorescence FITC to the reducing ends (Re) or main chain (Mc). The results of size exclusion chromatography, 13C NMR,fluorescence microscopy, FACS analyses and MTS assay demonstrated that non-toxic BG34 of 10 kDa(BG34-10) effectively trigger macrophage internalization. The internalization was adversely affected by modifying the main chain of BG34-10 but not the reducing end. Studies using blocking antibodies on several CD11b+ and CD11b− cells suggested that CD11b may play an important role in mediating macrophage internalization of BG34-10. Quantitative RT-PCR and intracellular cytokine stain revealed that macrophages generate increased level of CD11b and TNF-α in response to BG34-10. This study for the first time demonstrated the molecular size (10 kDa) and pattern of modification (reducing end modification)for BG34-10 to mediate macrophage internalization. Since BG34 is water soluble, biocompatible and biodegradable FDA-approved material, this mechanism of BG34-10 can be used to design drug delivery system targeting macrophages.

Influence of atorvastatin and carboxymethylated glucan on the serum lipoprotein profile and MMP activity of mice with lipemia induced by poloxamer 407

The effects of atorvastatin and carboxymethylated β-glucan (CMG) on the lipoprotein-cholesterol (LP-C) and lipoprotein-triglyceride (LP-TG) fractions and subfractions at the early stage of murine hyperlipidemia, and its pleiotropic anti-inflammatory effects, were studied. Atorvastatin and CMG were administered in ICR male mice with acute lipemia induced with a single injection of poloxamer 407 (P-407). A novel small-angle X-ray scattering method for the determination of fractional and subfractional composition of LP-C and LP-TG was used. In P-407-treated animals, there was a drastic increase of total cholesterol and especially TG. Atorvastatin decreased both the total cholesterol and TG, but not to control levels. CMG primarily decreased TG and was not as potent as atorvastatin. P-407 increased atherogenic LDL-C (IDL-C and LDL1–3-C subfractions) and very low-density lipoprotein-C (VLDL-C) (VLDL1–2-C and VLDL3–5-C subfractions) fractions, with an increase of the total anti-atherogenic HDL-C fraction (HDL2-C subfraction). Atorvastatin treatment of lipemia was followed by a decrease in the total LP-C, total LDL-C (LDL1–3-C subfraction), and the LDL1–3-TG subfraction. Additionally, atorvastatin treatment resulted in an increase in the serum matrix metalloproteases activity both in control and P-407-treated mice. In general, high-dose atorvastatin therapy exerts its lipid-lowering and pleiotropic effects in the early stages of acute lipemia induced in mice by treatment with P-407.

Influence of atorvastatin on fractional and subfractional composition of serum lipoproteins and MMP activity in mice with Triton WR 1339-induced lipaemia

OBJECTIVES

The effects of atorvastatin on the atherogenic and anti-atherogenic lipoprotein-cholesterol (C-LP) and lipoprotein-triglyceride (TG-LP) fractions and subfractions at the early stage of murine acute hyperlipidaemia, and its pleiotropic anti-inflammatory effects via the activity of matrix metalloproteinases (MMPs) were studied.

METHODS

Atorvastatin (75 mg/kg) was administered to ICR mice with acute lipaemia induced by a single injection of Triton WR 1339 (500 mg/kg). A novel small-angle X-ray scattering (SAXS) method was used for the determination of the fractional and subfractional composition of C-LP and TG-LP.

KEY FINDING

In Triton WR 1339-treated mice, there was a drastic increase in the atherogenic low-density C-LP (C-LDL) fraction, intermediate density lipoprotein-cholesterol (C-IDL) subfraction, and very low-density C-LP (C-VLDL) fractions (C-VLDL(3-5) subfraction). Additionally, there was an increase in the C-HDL(3) subfraction. Treatment of lipaemia with atorvastatin resulted in the normalization of the atherogenic C-LDL fraction and the C-IDL subfraction. A decrease in C-VLDL (C-VLDL(3-5) subfraction), total cholesterol and, especially, triglyceride (TG) concentrations was also demonstrated. Similar results were obtained with the TG-LP fractions and subfractions. Additionally, atorvastatin treatment resulted in an increase in the serum and liver MMP activity.

CONCLUSION

High-dose atorvastatin therapy exerts its rapid lipid-lowering and pleiotropic effect(s) in the early stages of acute lipaemia induced with Triton WR-1339.