Natural polysaccharides as potential anti-fibrotic agents: A review of their progress

Fibrosis, as a common disease which could be found in nearly all organs, is normally initiated by organic injury and eventually ended in cellular dysfunction and organ failure. Currently, effective and safe therapeutic strategies targeting fibrogenesis still in highly demand. Natural polysaccharides derived from natural resources possess promising anti-fibrosis potential, with no deleterious side effects. Based on the etiology and pathogenesis of fibrosis, this review summarizes the intervention effects and mechanisms of natural polysaccharides in the prevention and treatment of fibrosis. Natural polysaccharides are able to regulate each phase of the fibrogenic response, including primary injury to organs, activation of effector cells, the elaboration of extracellular matrix (ECM) and dynamic deposition. In addition, polysaccharides significantly reduce fibrosis levels in multiple organs including heart, lung, liver and kidney. The investigation of the pathogenesis of fibrosis indicates that mechanisms including the inhibition of TGF-β/Smad, NF-κB, HMGB1/TLR4, cAMP/PKA signaling pathways, MMPs/TIMPs system as well as microRNAs are promising therapeutic targets. Natural polysaccharides can target these mediators or pathways to alleviate fibrosis. The information reviewed here offer new insights into the understanding the protective role of natural polysaccharides against fibrosis, help design further experimental studies related to polysaccharides and fibrotic responses, and shed light on a potential treatment for fibrosis.

Indomethacin Sustained-Release Anti-adhesion Membrane Composed of a Phospholipid and Polycaprolactone Blend

Background

Postoperative peritoneal adhesions are among common challenging problems in surgery. The availability of limited efficient strategies to prevent intra-abdominal adhesion reinforces the need to explore new methods. Given the favorable prolonged drug release characteristics of polycaprolactone (PCL) films and their ability to act as a biodegradable physical barrier implant, along with the anti-inflammatory and anti-adhesion properties of indomethacin and phospholipids, this study hypothesized that indomethacin sustained-release membrane composed of phosphatidylcholine (PC) and PCL blend could efficiently prevent abdominal adhesion formation.

Methods

Different polymeric and polymeric/lipidic hybrid formulations with three feeding materials to drug weight ratios were prepared, and their physicochemical characteristics and drug release kinetics were evaluated and compared. Abdominal adhesions were induced in 48 rats by the abrasion of the cecum and excision of a section of the opposite abdominal wall. Adhesion formation was evaluated by macroscopic scoring, histological, scanning electron microscopy, and polymerase chain reaction analyses.

Results

Both PCL and PCL-PC films exhibited sustained indomethacin release profiles. The X-ray diffraction and Fourier-transform infrared spectroscopy studies confirmed indomethacin incorporation in formulations in molecular dispersion form without any interaction. The films showed smooth surfaces and good mechanical properties. The treatment with indomethacin PCL-PC membrane significantly reduced the expression levels of tumor necrosis factor-alpha, transforming growth factor-beta, interleukin-1, interleukin-6, and fibrinogen in the adhesion tissues. The separation of the injured peritoneum, very low adhesion scores, and complete mesothelial cell regeneration were also achieved.

Conclusions

This study suggests that indomethacin-eluting PCL-PC membrane acting through the combination of physical barrier, anti-inflammatory agents, and controlled drug delivery warrants an effective approach to prevent intra-abdominal adhesion.

Transcriptome sequencing analysis of primary fibroblasts: a new insight into postoperative abdominal adhesion

PURPOSE

The specific genes or pathways in fibroblasts responsible for the pathogenesis of postoperative abdominal adhesion (PAA) remain to be elucidated. We aim to provide a new insight into disease mechanisms at the transcriptome level.

METHODS

Male Sprague-Dawley rats were used to establish a PAA model. Primary fibroblasts were separated from normal peritoneal tissue (NF) and postoperative adhesion tissue (PF). RNA sequencing was used to analyze the transcriptome in NF and PF.

RESULTS

One thousand two hundred thirty-five upregulated and 625 downregulated DEGs were identified through RNA-Seq. A pathway enrichment analysis identified distinct enriched biological processes, among which the most prominent was related to immune and inflammatory response and fibrosis. HE staining and Masson's trichrome staining histologically validated the RNA-Seq results. Six hub genes, ITGAM, IL-1β, TNF, IGF1, CSF1R and EGFR were further verified by RT-PCR.

CONCLUSIONS

Our study revealed the roles of the immune and inflammatory responses and fibrosis in the process of PAA. We also found six hub genes that may be potential therapeutic targets for PPA.

Prevention of Post-Operative Adhesions: A Comprehensive Review of Present and Emerging Strategies

Post-operative adhesions affect patients undergoing all types of surgeries. They are associated with serious complications, including higher risk of morbidity and mortality. Given increased hospitalization, longer operative times, and longer length of hospital stay, post-surgical adhesions also pose a great financial burden. Although our knowledge of some of the underlying mechanisms driving adhesion formation has significantly improved over the past two decades, literature has yet to fully explain the pathogenesis and etiology of post-surgical adhesions. As a result, finding an ideal preventative strategy and leveraging appropriate tissue engineering strategies has proven to be difficult. Different products have been developed and enjoyed various levels of success along the translational tissue engineering research spectrum, but their clinical translation has been limited. Herein, we comprehensively review the agents and products that have been developed to mitigate post-operative adhesion formation. We also assess emerging strategies that aid in facilitating precision and personalized medicine to improve outcomes for patients and our healthcare system.

Subacute feeding toxicity of low-sodium sausages manufactured with sodium substitutes and biopolymer-encapsulated saltwort (Salicornia herbacea) in a mouse model

BACKGROUND

Low-sodium sausages were manufactured using sodium substitution and biopolymer encapsulation. A diet comprising 10% treatment sausages (six treatment groups: C (100% NaCl), T1 (55% sodium substitute + 45% saltwort salt), T2 (55% sodium substitute + 45% saltwort salt with chitosan), T3 (55% sodium substitute + 45% saltwort salt with cellulose), T4 (55% sodium substitute + 45% saltwort salt with dextrin), and T5 (55% sodium substitute + 45% saltwort salt with pectin)) was added to a 90% commercial mouse diet for 4 weeks.

RESULTS

Subacute toxicity, hematology, liver function, and organ weight tests in low-sodium sausage groups showed results similar to those of the control group, and all toxicity test levels were within normal ranges.

CONCLUSIONS

All low-sodium sausage types tested are suggested to be safe in terms of subacute toxicity. Moreover, low-sodium sausages can be manufactured by biopolymer encapsulation of saltwort using pectin, chitosan, cellulose, and dextrin without toxicity. © 2019 Society of Chemical Industry.

INVOLVEMENT OF JNK MAPK CASCADES IN THE FORMATION OF ADHESIONS IN THE ABDOMINAL CAVITY

Adhesive process in the abdominal cavity is one of the most frequent complications of intra-abdominal surgery.

The aim of the study was to evaluate the activation of the JNK MAPK cascade during the experimental adhesion process.

Materials and methods. Experimental studies were performed on 40 male Wistar rats (9 months old). We modeled the adhesive  process in the abdominal cavity. At the time from 2 hours (2, 6, 12  hours) to 30 days (1, 3, 7, 14, 30 days), a JNK MAPK cascade was  evaluated in the zone of damage to the serosa using  immunohistochemical methods (painting on JNK1 Phospho (pT183) /  JNK2 Phospho (pT183) / JNK3 Phospho (pT221)) and real-time  PCR (the MAP Kinase Signaling Pathway RT2 - Profiler ™ PCR Array  (Qiagen) kit). 

Results. We have found that the expression of the  phosphorylated part of the JNK MAPK cascades has an undulating dynamics with two  peaks on the 3rd and 14th day. It has been determined that all  three JNK cascades are involved in the process, and all JNK cascades are synchronously activated on the 3rd day (JNK1 increases 12-fold  in comparison with the group of intact animals, JNK2 is 8-fold, JNK3  is 10-fold). On the 14th day, the activity of the JNK3 cascade is the  most intensively increased – 30 times (for JNK1 – about 6 times,  JNK2 – 12 times). 

 

Conclusion. Significant activation of MARK cascades has been established on the 14th day after traumatic injury, which indicates the need for long-term prevention of posttraumatic changes, in particular, the formation of adhesions.