Extracellular polysaccharide from Bordetella species reduces high glucose-induced macrophage apoptosis via regulating interaction between caveolin-1 and TLR4

Protective role of ergothioneine isolated from Pleurotus ostreatus against dextran sulfate sodium-induced ulcerative colitis in rat model

The well-acknowledged sulfur-containing amino acid ergothioneine (EGT), which is usually perceived to be produced from fungi, cyanobacteria, and mushrooms, has been increasingly demonstrated as a diet-derived antioxidant with therapeutic potential. However, little is known regarding the therapeutic benefit against ulcerative colitis of EGT. Meanwhile, few studies have reported whether EGT could be produced by Pleurotus ostreatus, which is the second most cultivated edible mushroom worldwide, with ideal economic and ecological values and medicinal properties. In the current study, EGT was primarily extracted and isolated from P. ostreatus by water extraction and alcohol precipitation. Then, the Sephadex G-10 gel permeation chromatography and preparative high-performance liquid chromatography were employed in order to purify and collect EGT. Based on nuclear magnetic resonance spectrum characterization, the content of EGT extracted from P. ostreatus is 1.916 mg/g (the weight of EGT is the same as that of dry P. ostreatus). Finally, both the antioxidant activity in vitro and potential effects of EGT on dextran sulfate sodium-induced ulcerative colitis in rats were investigated. The results showed that the collected EGT exhibited strong antioxidant activity with a concentration-dependent manner in 1,1-diphenyl-2-picrylhydrazyl and 2,2'-azinobis (3-ethylbenzoline-6-sulphonic acid) assays. The oral administration of EGT can significantly alleviate colon length shortening and colonic pathological damage, mediated by downregulating the expression of pro-inflammatory factors and inhibiting TLR4/MyD88/NF-κB signaling pathway. Therefore, this study demonstrated that EGT from P. ostreatus would be an excellent dietary compound to ameliorate ulcerative colitis. PRACTICAL APPLICATION: In order to develop Pleurotus ostreatus as a functional food and related products for the prevention and treatment of ulcerative colitis, the separation and purification technology of ergothioneine (EGT) from P. ostreatus was studied, which not only provided a new and broader source for the acquisition and development of EGT, but also provided a basis for the development of EGT as a drug against UC.

Recent advances in peptide-based nanomaterials for targeting hypoxia

Hypoxia is a prominent feature of many severe diseases such as malignant tumors, ischemic strokes, and rheumatoid arthritis. The lack of oxygen has a paramount impact on angiogenesis, invasion, metastasis, and chemotherapy resistance. The potential of hypoxia as a therapeutic target has been increasingly recognized over the last decade. In order to treat these disease states, peptides have been extensively investigated due to their advantages in safety, target specificity, and tumor penetrability. Peptides can overcome difficulties such as low drug/energy delivery efficiency, hypoxia-induced drug resistance, and tumor nonspecificity. There are three main strategies for targeting hypoxia through peptide-based nanomaterials: (i) using peptide ligands to target cellular environments unique to hypoxic conditions, such as cell surface receptors that are upregulated in cells under hypoxic conditions, (ii) utilizing peptide linkers sensitive to the hypoxic microenvironment that can be cleaved to release therapeutic or diagnostic payloads, and (iii) a combination of the above where targeting peptides will localize the system to a hypoxic environment for it to be selectively cleaved to release its payload, forming a dual-targeting system. This review focuses on recent developments in the design and construction of novel peptide-based hypoxia-targeting nanomaterials, followed by their mechanisms and potential applications in diagnosis and treatment of hypoxic diseases. In addition, we address challenges and prospects of how peptide-based hypoxia-targeting nanomaterials can achieve a wider range of clinical applications.

Hepatoprotective effect of Saccharomyces Cervisciae Cell Wall Extract against thioacetamide-induced liver fibrosis in rats

Fibrosis represents a common outcome of almost all chronic liver diseases and leads to an impairment of liver function that requires medical intervention. The current study aimed to evaluate the potential anti-fibrotic effect of Saccharomyces cervisciae cell wall extract (SCCWE) against thioacetamide (TAA)-induced liver fibrosis in rats (200mg/kg b.w. i.p. twice weekly for 6 weeks) using Ursodeoxycholic acid (UDCA) as a reference anti-fibrotic product. SCCWE at two doses (50 and 100 mg/kg) significantly ameliorated the rise in serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), gamma glutamide transferase (GGT) activities, total bilirubin and direct bilirubin, increased total protein and albumin. SCCWE significantly reduced glutathione depletion (GSH), Nitric oxide (NOx) and malondialdehyde (MDA), thioredoxin (Trx) contents and elevated nuclear factor erythroid 2–related factor 2 (Nrf-2) content. Its anti-inflammatory effects were confirmed by observing a decrease in nuclear factor-κB (NF- κβ), interleukin-1b (IL-1β) and inducible nitric oxide synthase (iNOS) content. The anti-fibrotic effects of SCCWE were explored by assessing fibrosis related markers as it significantly reduced transform growth factor-β (TGF-β) and autotaxin (ATX) contents. Administration of SCCWE significantly decreased matrix metalloproteinase-3 and 9 (MMP-3 and -9). Furthermore, it also decreased alpha smooth muscle actin (α-SMA) and caspase-3 as assessed immunohistochemically those results were similar to that of the standard drug UDCA. This study shows that SCCWE protects against TAA-induced liver fibrosis in rats, through attenuating oxidative stress, and inflammation, ameliorating MMPs, combating apoptosis and thereby fibrotic biomarkers in addition to improving histopathological changes.

The Influence of Polysaccharides-Based Material on Macrophage Phenotypes

Macrophage polarization is a key factor in determining the success of implanted tissue engineering scaffolds. Polysaccharides (derived from plants, animals, and microorganisms) are known to modulate macrophage phenotypes by recognizing cell membrane receptors. Numerous studies have developed polysaccharide-based materials into functional biomaterial substrates for tissue regeneration and pharmaceutical application due to their immunostimulatory activities and anti-inflammatory response. They are used as hydrogel substrates, surface coatings, and drug delivery carriers. In addition to their innate immunological functions, the newly endowed physical and chemical properties, including substrate modulus, pore size/porosity, surface binding chemistry, and the mole ratio of polysaccharides in hybrid materials may regulate macrophage phenotypes more precisely. Growing evidence indicates that the sulfation pattern of glycosaminoglycans and proteoglycans expressed on polarized macrophages leads to the changes in protein binding, which may alter macrophage phenotype and influence the immune response. A comprehensive understanding of how different types of polysaccharide-based materials alter macrophage phenotypic changes can be beneficial to predict transplantation/implantation outcomes. This review focuses on recent advances in promoting wound healing and balancing macrophage phenotypes using polysaccharide-based substrates/coatings and new directions to address the limitations in the current understanding of macrophage responses to polysaccharides.

Macrophage cytokine responses to commensal Gram-positive Lactobacillus salivarius strains are TLR2-independent and Myd88-dependent

The mechanisms through which cells of the host innate immune system distinguish commensal bacteria from pathogens are currently unclear. Toll-like receptors (TLRs) are a class of pattern recognition receptors (PRRs) expressed by host cells which recognize microbe-associated molecular patterns (MAMPs) common to both commensal and pathogenic bacteria. Of the different TLRs, TLR2/6 recognize bacterial lipopeptides and trigger cytokines responses, especially to Gram-positive and Gram-negative pathogens. We report here that TLR2 is dispensable for triggering macrophage cytokine responses to different strains of the Gram-positive commensal bacterial species Lactobacillus salivarius. The L. salivarius UCC118 strain strongly upregulated expression of the PRRs, Mincle (Clec4e), TLR1 and TLR2 in macrophages while downregulating other TLR pathways. Cytokine responses triggered by L. salivarius UCC118 were predominantly TLR2-independent but MyD88-dependent. However, macrophage cytokine responses triggered by another Gram-positive commensal bacteria, Bifidobacterium breve UCC2003 were predominantly TLR2-dependent. Thus, we report a differential requirement for TLR2-dependency in triggering macrophage cytokine responses to different commensal Gram-positive bacteria. Furthermore, TNF-α responses to the TLR2 ligand FSL-1 and L. salivarius UCC118 were partially Mincle-dependent suggesting that PRR pathways such as Mincle contribute to the recognition of MAMPs on distinct Gram-positive commensal bacteria. Ultimately, integration of signals from these different PRR pathways and other MyD88-dependent pathways may determine immune responses to commensal bacteria at the host-microbe interface.

Swiprosin-1 deficiency impairs macrophage immune response of septic mice

Despite the fact that many therapeutic strategies have been adopted to delay the development of sepsis, sepsis remains one of the leading causes of death in noncoronary intensive care units. Recently, sepsis-3 was defined as life-threatening organ dysfunction due to a dysregulated host response to infection. Here, we report that swiprosin-1 (also known as EFhd2) plays an important role in the macrophage immune response to LPS-induced or cecal ligation and puncture-induced (CLP-induced) sepsis in mice. Swiprosin-1 depletion causes higher mortality, more severe organ dysfunction, restrained macrophage recruitment in the lung and kidney, and attenuated inflammatory cytokine production (including IL-1β, IL-6, TNF-α, IL-10, and IFN-γ). The immunosuppression caused by swiprosin-1 deficiency is manifested by impaired bactericidal capacity and decreased HLA-DR expression in macrophages. Swiprosin-1 affects the activation of the JAK2/STAT1/STAT3 pathway by regulating the expression of IFN-γ receptors in macrophages. Our findings provide a potential target for the regulation of the macrophage immune response in sepsis.

Therapeutic efficacy of nanomedicines for prostate cancer: An update

Recent advances in cancer nanomedicine have attracted remarkable attention in medical sectors. Pharmacologic research on nanomedicines, including targeted cancer therapy, has increased dramatically in the past 5 years. The success stories of nanomedicines in the clinical field include the fabrication of nanomedicines that show maximum loading efficiency into carriers, maximal release kinetics, and minimum toxicity to healthy cells. Nanoparticle-mediated medicines have been developed to specifically target prostate cancer tissue by use of aptamers, antibody targeting, and sustained release of nanomedicines in a dose- and time-dependent manner. Nanomedicines have been developed for therapeutic application in combination with image-guided therapy in real time. The scope of one of these nanomedicines, Abraxane (paclitaxel), may be extended to prostate cancer therapeutic applications for better quality of patient life and longer survival. This review provides an update on the latest directions and developments in nanomedicines for prostate cancer.