The Toll-like receptor 4 antagonist TAK-242 in combination with sodium hyaluronate alleviates postoperative abdominal adhesion in a mouse model.

Postoperative abdominal adhesion is one of the most common complications after abdominal surgery. The Toll-like receptor 4 (TLR4) signaling pathway is one of the most common inflammation-related pathways, and it has been demonstrated that TLR4 is highly expressed in adhesive tissues; however, the function of TLR4 in adhesion formation has not yet been studied. In the present study, the expression of TLR4 was first detected by immunohistochemical (IHC) and double-immunofluorescence staining in 40 mice, which were randomly divided into four groups, and sacrificed at 1, 3, 5 and 7 days after surgery. Subsequently, another 40 mice were randomly divided into five groups; with the exception of the sham group, the other groups were modeled and treated with saline that contained DMSO, sodium hyaluronate (HA), TAK-242 or TAK-242 + HA (applied to damaged peritoneal wounds). A total of 7 days after surgery, the mice were sacrificed and specimens were collected. Inflammation was detected by hematoxylin and eosin staining, and ELISA of transforming growth factor- ß1 (TGF-ß1) and interleukin-6 (IL-6); collagen deposition was examined by Masson staining and IHC staining of α-SMA; and reactive oxygen species (ROS) were detected by ROS staining and malondialdehyde (MDA) assay. The results revealed that TLR4 was highly expressed in the adhesive tissues at 3, 5 and 7 days after surgery. In addition, TAK-242 + HA treatment could reduce abdominal adhesion formation, exhibiting lower Nair's score and inflammation scores, lower TGF-ß1 and IL-6 levels, and lower collagen thickness and α-SMA levels compared with those in the control group. In addition, the TAK-242 + HA group had lower levels of ROS and MDA compared with those in the control group. The present study revealed that TLR4 was highly expressed in the process of adhesion formation and its inhibitor, TAK-242, combined with HA, could reduce adhesion formation by reducing inflammation and ROS, and alleviating collagen deposition.

A tough Janus poly(vinyl alcohol)-based hydrogel for wound closure and anti postoperative adhesion.

Traditional adhesive hydrogels perform well in tissue adhesion but they fail to prevent postoperative tissue adhesion. To address this challenge, a biodegradable Janus adhesive hydrogel (J-AH) was designed and fabricated by the assembly of three different functional layers including anti-adhesive layer, reinforceable layer, and wet tissue adhesive layer. Each layer of J-AH serves a specific function: the top zwitterionic polymeric anti-adhesive layer shows superior resistance to cell/protein and tissue adhesion; the middle poly(vinyl alcohol)/tannic acid reinforceable matrix layer endows the hydrogel with good mechanical toughness of ∼2.700 MJ/m3; the bottom poly(acrylic acid)/polyethyleneimine adhesive layer imparts tough adhesion (∼382.93 J/m2 of interfacial toughness) to wet tissues. In the rat liver and femoral injury models, J-AH could firmly adhere to the bleeding tissues to seal the wounds and exhibit impressive hemostatic efficiency. Moreover, in the in vivo adhesion/anti-adhesion assay of J-AH between the defected cecum and peritoneal walls, the top anti-adhesive layer can effectively inhibit undesired postoperative abdominal adhesion and inflammatory reaction. Therefore, this research may present a new strategy for the design of advanced bio-absorbable Janus adhesive hydrogels with multi-functions including tissue adhesion, anti-postoperative adhesion and biodegradation. STATEMENT OF SIGNIFICANCE: Despite many adhesive hydrogels with tough tissue adhesion capability have been reported, their proclivity for undesired postoperative adhesion remains a serious problem. The postoperative adhesion may lead to major complications and even endanger the lives of patients. The injectable hydrogels can cover the irregular wound and suppress the formation of postoperative adhesion. However, due to the lack of adhesive properties with tissue, it is difficult for the hydrogels to maintain on the wound surface, resulting in poor anti-postoperative adhesion effect. Herein, we design a Janus adhesive hydrogel (J-AH). J-AH integrates together robust wet tissue adhesion and anti-postoperative adhesion. Therefore, this research may present a new strategy for the design of advanced bio-absorbable Janus adhesive hydrogels.

Oenothera biennis improves pregnancy outcomes by suppressing inflammation and fibrosis in an intra-uterine adhesion rat model.

Intrauterine adhesion (IUA), also referred to as Asherman's syndrome, is characterized by fibrosis, inflammation, and can cause amenorrhea and infertility due to abnormal endometrial healing. Histological and Molecular methods were used to evaluate the efficacy of EPO, which is traditionally known for its anti-inflammatory and fibrinolytic properties, in preventing the formation of IUA. Oral administration of EPO reduced the formation of adhesion bands and promoted endometrial regeneration. EPO administration decreased extracellular matrix accumulation, evidenced by the down-regulation of tissue COL1A1 and COL3A1 expression. The anti-inflammatory effect of EPO was confirmed by a reduction in oxidants and down-regulation of pro-inflammatory cytokines including TNF-α, IL-6, IFN-γ, and IL-1ß. Furthermore, EPO improved embryonic development parameters, including size and weight of embryo, as well as increased embryo count and live embryo percentage in the rat IUA model. EPO also positively enhanced implantation markers, particularly enlargement and mass gain in the placenta of the treated group, consequently improving pregnancy outcomes such as the number of babies, percent of live babies, baby weight and gestation time. Histopathological investigation provides evidence that oral administration of EPO showed no toxicity on the main three organs including liver, kidney and heart. These results showed that EPO can be considered as a safe and natural product with potent anti-inflammatory and fibrinolytic properties without any observed side effects for the treatment of IUA.

Dipyridamole-grafted copolymer electrospun nanofiber membranes for suppression of peritendinous adhesions.

Post-traumatic tendon adhesions significantly affect patient prognosis and quality of life, primarily stemming from the absence of effective preventive and curative measures in clinical practice. Current treatment modalities, including surgical excision and non-steroidal anti-inflammatory drugs, frequently exhibit limited efficacy or result in severe side effects. Consequently, the use of anti-adhesive barriers for drug delivery and implantation at the injury site to address peritendinous adhesion (PA) has attracted considerable attention. Electrospun nanofiber membranes (ENMs) have been extensively employed as drug-delivery platforms. In this study, we fabricated a polylactic acid (PLA)-dipyridamole (DP)-graft copolymer ENM called PLC-DP. This membrane exhibits enzyme-sensitive features, allowing more controlled and sustained drug release compared with conventional drug-loaded ENMs. In experiments, PLC-DP implantation reduced tissue adhesion by 47 % relative to the control group while not adversely affecting tendon healing. Mechanistically, PLC-DP effectively activates the FXYD domain containing ion-transport regulator 2 (FXYD2) protein, thereby downregulating the fibroblast-transforming growth factor beta (TGF-ß)/Smad3 signaling pathway. PLC-DP leverages the anti-adhesive properties of DP and the enzyme-sensitive characteristics of graft copolymers, providing a promising approach for the future clinical treatment and prevention of PA. STATEMENT OF SIGNIFICANCE: Peritendinous adhesions (PA) are a common and disabling condition that seriously affects the prognosis and quality of life of post-trauma patients. Current treatments often have limited efficacy or severe side effects, leaving a serious gap in clinical practice. We developed a significant biomaterial, poly(lactic acid)-dipyridamole graft copolymer electrospun nanofibrous membrane (PLC-DP), specifically for PA inhibition. In addition, this study uniquely combines dipyridamole, an anti-adhesive agent, and enzyme-sensitive copolymers in electrospun nanofibrous membrane. Unlike conventional drug-loaded electrospun nanofibrous membranes, PLC-DPs have enzyme-sensitive drug properties that allow for sustained drug release on demand. Our experiments showed that implantation of PLC-DP was effective in reducing tissue adhesions by 47 % without affecting tendon healing. We elucidated the mechanism behind this phenomenon, suggesting that PCD activates FXYD2 to inhibit TGF-ß-induced expression of Col III, which is a key factor in PA development.

Apelin-13 alleviates intrauterine adhesion by inhibiting epithelial-mesenchymal transition of endometrial epithelial cells and promoting angiogenesis.

Intrauterine adhesion (IUA) is a common complication of surgical manipulation of the uterine cavity such as abortion. The pathology of IUA is characterized by fibrosis, but the pathogenesis is not fully understood. The function of Apelin-13 in IUA and related mechanisms were investigated in this study. The IUA rat model was established. The pathological changes and fibrosis degree of rat uterine tissues were detected by HE and Masson staining after intraperitoneal injection of Apelin-13. Epithelial-mesenchymal transition (EMT) of endometrial epithelial cells and endothelial-mesenchymal transition (EnMT) of vein endothelial cells were induced by TGF-ß1. Tube-forming assay using HUVEC was implemented to detect the effect of Apelin-13 upon angiogenesis. IHC staining, immunofluorescence staining, and Western blot were conducted to detect the expression levels of EMT markers, angiogenesis, and key proteins of the TGF-ß1/Smad signaling. Apelin-13 significantly alleviated IUA and fibrosis, and increased endometrial thickness and gland number in IUA rats. In addition, Apelin-13 significantly reversed EMT and EnMT induced by IUA modeling and TGF-ß1, promoted the tube-forming ability of HUVEC, and up-regulated the expression of angiogenesis-related proteins. Mechanistically, Apelin-13 significantly suppressed smad2/3 phosphorylation and inhibited the TGF-ß1/Smad signaling via its receptor APJ. Apelin-13 might alleviate IUA via repressing the TGF-ß1/Smad pathway and is expected to be a potent therapeutic option for the clinical treatment of IUA.

Interleukin-33 promotes intrauterine adhesion formation in mice through the mitogen-activated protein kinase signaling pathway.

IL-33 belongs to the inflammatory factor family and is closely associated with the inflammatory response. However, its role in the development of intrauterine adhesions (IUAs) remains unclear. In this study, the role of IL-33 in the formation of IUAs after endometrial injury was identified via RNA sequencing after mouse endometrial organoids were transplanted into an IUA mouse model. Major pathological changes in the mouse uterus, consistent with the expression of fibrotic markers, such as TGF-ß, were observed in response to treatment with IL-33. This finding may be attributed to activation of the phosphorylation of downstream MAPK signaling pathway components, which are activated by the release of IL-33 in macrophages. Our study provides a novel mechanism for elucidating IUA formation, suggesting a new therapeutic strategy for the prevention and clinical treatment of IUAs.

Visceral to subcutaneous fat area ratio predicts severe abdominal adhesions in definitive surgery for anastomotic fistula after small intestine resection.

Abdominal adhesions manifests following abdominal infections triggered by intestinal fistulas. The severity of such adhesions depends on the extent of fiber deposition and peritoneal fibrinolysis following peritoneal injury, which may be influenced by sustained inflammation within the abdominal cavity. In this regard, the visceral-to-subcutaneous fat area (VFA/SFA) ratio has been implicated as a potential marker of inflammation. This study aimed to explore the relationship between VFA/SFA and abdominal adhesions. This multicenter study was conducted across four tertiary institutions and involved patients who had undergone definitive surgery (DS) for intestinal fistula from January 2009 and October 2023. The presence of abdominal adhesions was determined intraoperatively. VFA/SFA was investigated as a potential risk factor for severe adhesions. The study comprised 414 patients with a median age of 50 [interquartile range (IQR) 35-66] years and a median body mass index of 20.0 (IQR 19.2-22.4) kg/m2, including 231 males with a median VFA/SFA of 1.0 (IQR 0.7-1.2) and 183 females a median VFA/SFA of 0.8 (0.6-1.1). VFA/SFA was associated with severe abdominal adhesions in males [odds ratio (OR) = 3.34, 95% CI 1.14-9.80, p = 0.03] and females (OR = 2.99, 95% CI 1.05-8.53, p = 0.04). J-shaped association between VFA/SFA ratio and severe adhesions was revealed in both sex. The increasing trend can be revealed when OR more than 0.8, and 0.6 in males and females respectively. Preoperative VFA/SFA demonstrates predictive value for statues of severe abdominal adhesions in DS for anastomotic fistula after small intestine resection.

Evaluation of Interaction With Bio-absorbable Polyglycolic Acid Spacer and Anti-adhesive Agents Using a Rat Experimental Model.

BACKGROUND/AIM: Neskeep®, an absorbable polyglycolic acid spacer, has been developed as the optimal material for spacer placement surgery. However, preventing its severe adhesion is a crucial concern. Therefore, we aimed to identify an effective anti-adhesion agent for Neskeep® using rat models. MATERIALS AND METHODS: Animal experiments were performed using 60 rats, which underwent Neskeep® placement on the abdominal wall. Three types of anti-adhesion agents were employed, establishing four subgroups: Seprafilm®, INTERCEED®, AdSpray®, and only Neskeep® (control) groups. Rats were sacrificed on postoperative days 7, 14, and 28 to assess adhesion levels around the Neskeep® Macroscopic visual assessment with the Lauder score and histopathological evaluation were performed to assess the degree of adhesion. RESULTS: There were no significant differences in the proportion of Lauder scores on days 7 and 14 between the four groups. Histological evaluation revealed no significant differences between groups at any observation time. However, the mean Lauder scores at day 28 were 5.0, 1.6, 4.0, and 4.8 in the Neskeep®, Seprafilm®, INTERCEED®, and AdSpray® groups, respectively. The proportion of milder Lauder score was significantly higher in the Seprafilm® group on day 28. CONCLUSION: Seprafilm® may exhibit an anti-adhesive effect when used with Neskeep®.

Injectable, degradable, and mechanically adaptive hydrogel induced by L-serine and allyl-functionalized chitosan with platelet-rich plasma for treating intrauterine adhesions.

The integration of barrier materials with pharmacological therapy is a promising strategy to treat intrauterine adhesions (IUAs). However, most of these materials are surgically implanted in a fixed shape and incongruence with the natural mechanical properties of the uterus, causing poor adaptability and significant discomfort to the patients. Herein, an injectable, biodegradable, and mechanically adaptive hydrogel loaded with platelet-rich plasma (PRP) is created by L­serine and allyl functionalized chitosan (ACS) to achieve efficient, comfortable, and minimally invasive treatment of IUAs. L­serine induces fast gelation and mechanical reinforcement of the hydrogel, while ACS introduces, imparting a good injectability and complaint yet strong feature to the hydrogel. This design enables the hydrogel to adapt to the complex geometry and match the mechanical properties of the uterine. Moreover, the hydrogel exhibits proper degradability, sustained growth factors (GFs) of PRP release ability, and good biocompatibility. Consequently, the hydrogel shows promising therapeutic efficacy by reducing collagen fiber deposition and facilitating endometrium cell proliferation, thereby restoring the fertility function of the uterus in an IUAs model of rats. Accordingly, the combination of L­serine and ACS-induced hydrogel with such advantages holds great potential for treating IUAs. STATEMENT OF SIGNIFICANCE: This research introduces a breakthrough in the treatment of intrauterine adhesions (IUAs) with an injectable, biodegradable and mechanically adaptive hydrogel using L­serine and allyl functionalized chitosan (ACS). Unlike traditional surgical treatments, this hydrogel uniquely conforms to the uterus's geometry and mechanical properties, offering a minimally invasive, comfortable, and more effective solution. The hydrogel is designed to release growth factors from platelet-rich plasma (PRP) sustainably, promoting tissue regeneration by enhancing collagen fiber deposition and endometrium cell proliferation. Demonstrated efficacy in a rat model of IUAs indicates its great potential to significantly improve fertility restoration treatments. This advancement represents a significant leap in reproductive medicine, promising to transform IUAs treatment with its innovative approach to achieving efficient, comfortable, and minimally invasive therapy.

Establishment and evaluation of a stable and reliable rat model of peritoneal adhesions.

BACKGROUND: In this study, we aimed to establish a stable and standardized animal model of peritoneal adhesions. METHODS: Forty-eight male Sprague-Dawley rats were randomly divided (n = 12 each) into blank control, classic cecum sidewall, ischemic button, and cecum-sidewall suture groups. The modified American Fertility Society adhesion score was used on postoperative day 7 to evaluate adhesions. Sixty male Sprague-Dawley rats were used to dynamically observe the adhesion characteristics of cecum-sidewall ischemic injury suture model at different time points (n = 60, randomly divided into groups a-e with 12 rats each). The modified American Fertility Society and Zühlke histologic scoring systems, hematoxylin-eosin staining, Masson staining, and computed tomography of the abdomen were used to evaluate adhesions on postoperative days 1, 3, 5, 7, and 14. RESULTS: No peritoneal adhesions were observed in the blank control group on postoperative day 7. In the classic cecum sidewall group, 8 rats had inconsistent adhesions, which had a modified American Fertility Society adhesion score of 2.25 ± 1.96. All rats in the ischemic button and cecum-sidewall suture groups developed significant adhesions with modified American Fertility Society scores of 3.08 ± 1.31 and 4.67 ± 0.78, respectively. When the modified American Fertility Society score was used, statistically significant differences were observed between the classic cecum sidewall groups and cecum-sidewall suture groups and between the ischemic button groups and cecum-sidewall suture groups. All animals in groups a-e developed adhesions; adhesion scores increased gradually with time. CONCLUSIONS: The cecum-sidewall ischemic injury suture model is a stable and standardized animal model of peritoneal adhesions.

A ROS-responsive and scavenging hydrogel for postoperative abdominal adhesion prevention.

Postoperative abdominal adhesion (PAA) widely occurs after abdominal surgery, which often produces severe complications. However, there were still no satisfactory anti-adhesive products including barriers and anti-adhesive agents. Herein, we developed a ROS-responsive and scavenging hydrogel barrier, termed AHBC/PSC, wherein the monomer AHBC was synthesized by phenylboronic acid (PBA)-modified hyaluronic acid (HA-PBA) further grafted with adipic dihydrazide (ADH) and PBA-based chlorogenic acid (CGA) via ROS-sensitive borate ester bond, and the other monomer PSC was constructed by polyvinyl alcohol (PVA) grafted with sulfated betaine (SB) and p-hydroxybenzaldehyde (CHO). Further, the double crosslinked AHBC/PSC hydrogel was successfully fabricated between AHBC and PSC via forming dynamic covalent acylhydrazone bonds and borate ester bonds. Results showed that AHBC/PSC hydrogel had in situ gelation behavior, satisfactory mechanical properties (storage modulus of about 1 kPa and loss factor Tan δ of about 0.5), suitable wet tissue adhesion strength of about 2.3 kPa on rat abdominal wall, and good biocompatibility, achieving an ideal physical barrier. Particularly, CGA could be responsively released from the hydrogel by breakage of borate ester bonds between CGA and PBA based on high reactive oxygen species (ROS) levels of damaged tissue and exhibited great ROS scavenging capability to regulate inflammation and promote the polarization of macrophages from pro-inflammatory M1 phenotype to anti-inflammatory M2 phenotype. Moreover, the grafted SB as a zwitterionic group could reduce protein adsorption and fibroblast adhesion. Finally, the in vivo experiments revealed that AHBC/PSC hydrogel with good safety and in vivo retention behavior of about 2 weeks, effectively prevented PAA by regulating the inflammatory microenvironment and alleviating the fibrosis process. In brief, the versatile AHBC/PSC hydrogel would provide a more convenient and efficient approach for PAA prevention. STATEMENT OF SIGNIFICANCE: Postoperative abdominal adhesion (PAA) widely occurs after surgery and is often accompanied by severe complications. Excessive inflammation and oxidative stress are very crucial for PAA formation. This study provides a ROS-responsive and scavenging hydrogel with suitable mechanical properties, good biocompatibility and biodegradability, and resistance to protein and fibroblast. The antioxidant and anti-inflammatory active ingredient could be responsively released from the hydrogel via triggering by the high ROS levels in the postoperative microenvironment thereby regulating the inflammatory balance. Finally, the hydrogel would effectively regulate the development process of PAA thereby achieving non-adhesion wound healing.

Neutrophil Extracellular Traps: A Crucial Factor in Post-Surgical Abdominal Adhesion Formation.

Post-surgical abdominal adhesions, although poorly understood, are highly prevalent. The molecular processes underlying their formation remain elusive. This review aims to assess the relationship between neutrophil extracellular traps (NETs) and the generation of postoperative peritoneal adhesions and to discuss methods for mitigating peritoneal adhesions. A keyword or medical subject heading (MeSH) search for all original articles and reviews was performed in PubMed and Google Scholar. It included studies assessing peritoneal adhesion reformation after abdominal surgery from 2003 to 2023. After assessing for eligibility, the selected articles were evaluated using the Critical Appraisal Skills Programme checklist for qualitative research. The search yielded 127 full-text articles for assessment of eligibility, of which 7 studies met our criteria and were subjected to a detailed quality review using the Critical Appraisal Skills Programme (CASP) checklist. The selected studies offer a comprehensive analysis of adhesion pathogenesis with a special focus on the role of neutrophil extracellular traps (NETs) in the development of peritoneal adhesions. Current interventional strategies are examined, including the use of mechanical barriers, advances in regenerative medicine, and targeted molecular therapies. In particular, this review emphasizes the potential of NET-targeted interventions as promising strategies to mitigate postoperative adhesion development. Evidence suggests that in addition to their role in innate defense against infections and autoimmune diseases, NETs also play a crucial role in the formation of peritoneal adhesions after surgery. Therefore, therapeutic strategies that target NETs are emerging as significant considerations for researchers. Continued research is vital to fully elucidate the relationship between NETs and post-surgical adhesion formation to develop effective treatments.

Semaglutide May Ameliorate Fibrosis and Inhibit Epithelial-Mesenchymal Transition in Intrauterine Adhesion Models.

The purpose of this study was to explore the effect of Semaglutide on intrauterine adhesions and discover new drugs for such adhesions. In this study, the cell model was simulated by TGF-ß1-induced human endometrial epithelial cells, and the animal model was established through mechanical curettage and inflammatory stimulation. After co-culturing with TGF-ß1 with or without different concentrations of Semaglutide for 48 h, cells were collected for RT-qPCR and Western blotting analyses. Three doses were subcutaneously injected into experimental mice once a day for two weeks, while the control group received sterile ddH2O. The serum and uterine tissues of the mice were collected. HE and Masson staining were used for the uterine histomorphological and pathological analyses. RT-qPCR and Western blotting were used for mRNA and protein expression analyses. Serum indicators were detected using ELISA kits. The results showed that Semaglutide significantly reduced the mRNA levels of fibrosis indicators ACTA2, COL1A1, and FN and inflammatory indicators TNF-α, IL-6, and NF-κB in the two models. Semaglutide improved endometrium morphology, increased the number of endometrial glands, and reduced collagen deposition in IUA mice. The results also showed that Semaglutide could inhibit vimentin, E-Cadherin, and N-Cadherin in the two models. In summary, Semaglutide can ameliorate fibrosis and inflammation of intrauterine adhesions as well as inhibit epithelial-mesenchymal transition in IUA models.

Human amnion mesenchymal stem cells promote endometrial repair via paracrine, preferentially than transdifferentiation.

BACKGROUND: Intrauterine adhesion (IUA) is one of the most severe causes of infertility in women of childbearing age with injured endometrium secondary to uterine performance. Stem cell therapy is effective in treating damaged endometrium. The current reports mainly focus on the therapeutic effects of stem cells through paracrine or transdifferentiation, respectively. This study investigates whether paracrine or transdifferentiation occurs preferentially in treating IUA. METHODS: Human amniotic mesenchymal stem cells (hAMSCs) and transformed human endometrial stromal cells (THESCs) induced by transforming growth factor beta (TGF-ß1) were co-cultured in vitro. The mRNA and protein expression levels of Fibronectin (FN), Collagen I, Cytokeratin19 (CK19), E-cadherin (E-cad) and Vimentin were detected by Quantitative real-time polymerase chain reaction (qPCR), Western blotting (WB) and Immunohistochemical staining (IHC). The Sprague-Dawley (SD) rats were used to establish the IUA model. hAMSCs, hAMSCs-conditional medium (hAMSCs-CM), and GFP-labeled hAMSCs were injected into intrauterine, respectively. The fibrotic area of the endometrium was evaluated by Masson staining. The number of endometrium glands was detected by hematoxylin and eosin (H&E). GFP-labeled hAMSCs were traced by immunofluorescence (IF). hAMSCs, combined with PPCNg (hAMSCs/PPCNg), were injected into the vagina, which was compared with intrauterine injection. RESULTS: qPCR and WB revealed that FN and Collagen I levels in IUA-THESCs decreased significantly after co-culturing with hAMSCs. Moreover, CK19, E-cad, and Vimentin expressions in hAMSCs showed no significant difference after co-culture for 2 days. 6 days after co-culture, CK19, E-cad and Vimentin expressions in hAMSCs were significantly changed. Histological assays showed increased endometrial glands and a remarkable decrease in the fibrotic area in the hAMSCs and hAMSCs-CM groups. However, these changes were not statistically different between the two groups. In vivo, fluorescence imaging revealed that GFP-hAMSCs were localized in the endometrial stroma and gradually underwent apoptosis. The effect of hAMSCs by vaginal injection was comparable to that by intrauterine injection assessed by H&E staining, MASSON staining and IHC. CONCLUSIONS: Our data demonstrated that hAMSCs promoted endometrial repair via paracrine, preferentially than transdifferentiation.

IUA is the crucial cause of infertility in women of childbearing age, and no satisfactory treatment measures have been found in the clinic. hAMSCs can effectively treat intrauterine adhesions through paracrine and transdifferentiation mechanisms. This study confirmed in vitro and in vivo that amniotic mesenchymal stem cells preferentially inhibited endometrial fibrosis and promoted epithelial repair through paracrine, thus effectively treating intrauterine adhesions. The level of fibrosis marker proteins in IUA-THESCs decreased significantly after co-culturing with hAMSCs for 2 days in vitro. However, the level of epithelial marker proteins in hAMSCs increased significantly, requiring at least 6 days of co-culture. hAMSCs-CM had the same efficacy as hAMSCs in inhibiting fibrosis and promoting endometrial repair in IUA rats, supporting the idea that hAMSCs promoted endometrial remodeling through paracrine in vivo. In addition, GFP-labeled hAMSCs continuously colonized the endometrial stroma instead of the epithelium and gradually underwent apoptosis. These findings prove that hAMSCs ameliorate endometrial fibrosis of IUA via paracrine, preferentially than transdifferentiation, providing the latest insights into the precision treatment of IUA with hAMSCs and a theoretical basis for promoting the "cell-free therapy" of MSCs.

Comparison of the effect of Everolimus, Prednisolone, and a combination of both on experimentally induced peritoneal adhesions in rats.

Postoperative intra-abdominal adhesions represent a significant post-surgical problem. Its complications can cause a considerable clinical and cost burden. Herein, our study aimed to investigate the effect of Everolimus on peritoneal adhesion formation after inducing adhesions in rats. In this experimental study, adhesion bands were induced by intraperitoneal injection of 3 ml of 10% sterile talc solution in 64 male albino rats. The first group served as the control group. The second one received oral Prednisolone (1 mg/kg/day), the third received Everolimus (0.1 mg/kg/day), and group four received both drugs with similar dosages for four consecutive weeks. The formation of adhesion bands was qualitatively graded according to the Nair classification. The rats in the control group had extensive adhesions between the abdominal wall and the organs. Regarding substantial adhesion formation, 50% (8/16) of animals in the control group had substantial adhesions, while this rate in the groups receiving Prednisolone, Everolimus, and combination treatment was 31%, 31%, and 31%, respectively. Also, 68.75% (5/11) of the Prednisolone recipients had insubstantial adhesions, the same as Everolimus recipients, while in the combination group, 66.66% (10/15) rats had insubstantial adhesions. Everolimus demonstrated satisfactory results in reducing the rates of induced peritoneal adhesion in an experimental model, similar to Prednisolone and superior to a combination regime.

The effect of papaverine on tendon healing and adhesion in rats following Achilles tendon repair.

OBJECTIVES: The study aimed to examine the histopathological and biomechanical effects of papaverine administered intraperitoneally and locally on Achilles tendon healing in a rat model. MATERIALS AND METHODS: Forty-eight adult male Sprague-Dawley rats (range, 300 to 400 g) were used in this study conducted between October and November 2022. The rats were divided into three groups, with each group further subdivided into two for sacrifice on either the 15th (early period) or 30th (late period) day after surgery. The first (control) group received no treatment following Achilles tendon repair, while papaverine was intraperitoneally administered every other day for 10 days in the second group and locally in the third group after surgery. On the 15th and 30th days, the rats were sacrificed, and their Achilles tendons were subjected to biomechanical testing and histopathological evaluation. RESULTS: Histopathologically, there were no significant differences among the groups on the 15th day. However, on the 30th day, the locally applied papaverine group exhibited superior histopathological outcomes compared to the control group (p<0.05). Concerning the highest tensile strength values before rupture, the biomechanical assessment showed that the group receiving local papaverine treatment in the early period and both the group with systemic papaverine treatment and the one with local papaverine treatment in the late period displayed a statistically significant advantage compared to the control group (p<0.05). CONCLUSION: Locally administered papaverine has positive biomechanical effects in the early period and exhibits a positive correlation both histopathologically and biomechanically in the late period. Novel therapeutic options may be provided for patients through these findings.

Repurposing of Angiotensin-converting-enzyme Inhibitor on Prevention of Post-surgical Tendon Adhesion.

BACKGROUND: Formation of adhesion bands is a frequent clinical complication after tendon injury or surgery with limited treatment options. This study investigates the repurposing of Angiotensin-Converting-Enzyme Inhibitor (ACEI) in attenuating post-operative tendon-sheath adhesion bands in an Achilles tendon rat model. METHODS: Structural, mechanical, histological, and biochemical characteristics of the Achilles tendons were compared in the presence and absence of oral ACEI (enalapril) using the Achilles tendon adhesion (TA) model in rats. Inflammation and total fibrosis of tendon tissues were compared between groups using molecular investigations along with macroscopic and histological scoring methods. RESULTS: ACEI significantly alleviated the severity, length, and density of Achilles TAs. Moreover, histopathological changes, recruitment of inflammatory cells, and inflammation were significantly decreased in post-operative tissue samples as quantified with the Moran scoring model. We showed that ACEI treatment elicits a potent anti-fibrotic effect on tendon tissue samples, as illustrated by decreasing the severity and extent of the formed fibrotic tissue and collagen accumulation at the site of surgery when scored either by Tang or Ishiyama grading systems. The H&E staining showed no histopathological changes or damage to the principal organs. CONCLUSION: Our results showed that ACEI is a safe and effective therapeutic candidate with potent immunomodulatory and anti-fibrotic features to alleviate surgery-induced development of fibrotic adhesive tissue. However, its efficacy needs to be further validated in clinical studies.

Investigation of anti-adhesion ability of 8-arm PEGNHS-modified porcine pericardium.

In post-adhesion surgery, there is a clinical need for anti-adhesion membranes specifically designed for the liver, given the limited efficacy of current commercial products. To address this demand, we present a membrane suitable for liver surgery applications, fabricated through the modification of decellularized porcine pericardium with 20 KDa hexaglycerol octa (succinimidyloxyglutaryl) polyoxyethylene (8-arm PEGNHS). We also developed an optimized modification procedure to produce a high-performance anti-adhesion barrier. The modified membrane significantly inhibited fibroblast cell adherence while maintaining minimal levels of inflammation. By optimizing the modification ratio, we successfully controlled post-adhesion formation. Notably, the 8-arm PEG-modified pericardium with a molar ratio of 5 exhibited the ability to effectively prevent post-adhesion formation on the liver compared to both the control and Seprafilm®, with a low adhesion score of 0.5 out of 3.0. Histological analysis further confirmed its potential for easy separation. Furthermore, the membrane demonstrated regenerative capabilities, as evidenced by the proliferation of mesothelial cells on its surface, endowing anti-adhesion properties between the abdominal wall and liver. These findings highlight the membrane's potential as a reliable barrier for repeated liver resection procedures that require the removal of the membrane multiple times.

Novel therapeutic targets, including IGFBP3, of umbilical cord mesenchymal stem-cell-conditioned medium in intrauterine adhesion.

Mesenchymal stem cells play important roles in repairing injured endometrium. However, the molecular targets and potential mechanism of the endometrial recipient cells for stem cell therapy in intrauterine adhesion (IUA) are poorly understood. In this study, umbilical cord mesenchymal stem-cell-conditioned medium (UCMSCs-CM) produced positive effects on a Transforming growth factor beta (TGF-ß) induced IUA cell model. RNA-sequencing was performed on clinical IUA tissues, and the top 40 upregulated and top 20 downregulated mRNAs were selected and verified using high-throughput (HT) qPCR in both tissues and cell models. Based on a bioinformatic analysis of RNA-sequencing and HT-qPCR results, 11 mRNAs were uncovered to be the intervention targets of UCMSCs-CM on IUA endometrium cell models. Among them, IGFBP3 was striking as a key pathogenic gene and a potential diagnostic marker of IUA, which exhibited the area under the curve (AUC), sensitivity, specificity were 0.924, 93.1% and 80.6%, respectively in 60 endometrial tissues. The silencing of IGFBP3 exerted positive effects on the IUA cell model through partially upregulating MMP1 and KLF2. In conclusion, RNA-sequencing combined with HT qPCR based on clinical tissues and IUA cell models were used in IUA research and our results may provide some scientific ideas for the diagnosis and treatment of IUA.