Metalloproteinase Inhibitor Research Articles

Abstract 4136905: EF-24, a curcumin analog, reverses interleukin-18-induced miR-30b or miR-342-dependent TRAF3IP2 expression, RECK suppression, and the proinflammatory phenotype of human aortic smooth muscle cells

Curcumin, a polyphenolic compound derived from the widely used spice Curcuma longa, has shown anti-atherosclerotic effects in cultured vascular cells and animal models. We previously reported that the induction of the proinflammatory molecule TRAF3IP2 (TRAF3 Interacting protein 2) or inhibition of the matrix metalloproteinase (MMP) regulator RECK (Reversion Inducing Cysteine Rich Protein with Kazal Motifs) contributes to agonist-induced proinflammatory, pro-oxidant, pro-mitogenic and pro-migratory effects in vascular smooth muscle cells. Here we hypothesized that, EF-24 ((3E,5E)-3,5-bis[2-fluorophenyl (methylene]-4piperidinone), a curcumin analog with better bioavailability and potency, reverses interleukin (IL)-18-induced TRAF3IP2 induction, RECK suppression and the proinflammatory phenotype of primary human aortic smooth muscle cells (ASMC). Exposure to recombinant human IL-18 (10 ng/ml) induced TRAF3IP2 mRNA and protein expression, but markedly suppressed RECK in a time-dependent manner. Further investigations revealed that IL-18 induced miR-30b, but suppressed miR-342, in a p38 MAPK and JNK-dependent manner. While miR-30b inhibitor blunted IL-18-induced TRAF3IP2 expression, miR-30b inhibitor and miR-342 mimic each restored RECK expression. Further, IL-18 induced ASMC migration (Boyden chamber assay) and proliferation (CyQUANT Cell Proliferation assay), and these effects were reversed by TRAF3IP2 knockdown or RECK overexpression. Our results also show that IL-18 induced MMP2 and MMP9 expression and activity, and targeting their expression inhibited IL-18-induced ASMC migration. TRAF3IP2 knockdown or RECK overexpression also reversed IL-18-induced ASMC proinflammatory phenotype switching as evidenced by the enhanced expression of the SMC markers ACTA2 and MYH11, and reduced expression of the proinflammatory markers Galectin 3, Olr1, VCAM, CCL2, IL-6, IL-8, and TNF-α. Importantly, preincubation with EF-24 markedly suppressed IL-18-induced SMC proliferation, MMP expression, migration and the proinflammatory phenotype switching. Together, these results suggest that the curcumin analog EF-24 has therapeutic potential in vascular inflammatory and proliferative diseases, including atherosclerosis, by differentially regulating TRAF3IP2 and RECK in vascular SMC.

A Novel P-III Metalloproteinase from Bothrops barnetti Venom Degrades Extracellular Matrix Proteins, Inhibits Platelet Aggregation, and Disrupts Endothelial Cell Adhesion via α5β1 Integrin Receptors to Arginine–Glycine–Aspartic Acid (RGD)-Containing Molecules

Viperid snake venoms are notably abundant in metalloproteinases (proteins) (SVMPs), which are primarily responsible for inducing hemorrhage and disrupting the hemostatic process and tissue integrity in envenomed victims. In this study, barnettlysin-III (Bar-III), a hemorrhagic P-III SVMP, was purified from the venom of the Peruvian snake Bothrops barnetti. Bar-III has a molecular mass of approximately 50 kDa and is a glycosylation-dependent functional metalloproteinase. Some biochemical properties of Bar-III, including the full amino acid sequence deduced from its cDNA, are reported. Its enzymatic activity is increased by Ca2+ ions and inhibited by an excess of Zn2+. Synthetic metalloproteinase inhibitors and EDTA also inhibit its proteolytic action. Bar-III degrades several plasma and ECM proteins, including fibrin(ogen), fibronectin, laminin, and nidogen. Platelets play a key role in hemostasis and thrombosis and in other biological process, such as inflammation and immunity, and platelet activation is driven by the platelet signaling receptors, glycoprotein (GP)Ib-IX-V, which binds vWF, and GPVI, which binds collagen. Moreover, Bar-III inhibits vWF- and convulxin-induced platelet aggregation in human washed platelets by cleaving the recombinant A1 domain of vWF and GPVI into a soluble ectodomain fraction of ~55 kDa (sGPVI). Bar-III does not reduce the viability of cultured endothelial cells; however, it interferes with the adhesion of these cells to fibronectin, vitronectin, and RGD peptides, as well as their migration profile. Bar-III binds specifically to the surface of these cells, and part of this interaction involves α5β1 integrin receptors. These results contribute to a better comprehension of the pathophysiology of snakebite accidents/incidents and could be used as a tool to explore novel and safer anti-venom therapeutics.

Metalloproteinase inhibitors in the adhesion process dental

Matrix metalloproteinases (MMPs) are enzymes involved in tooth physiological development, caries processes, and hybrid layer degradation, in addition to being associated with dentin collagen breakdown. The interplay of MMP activity, masticatory forces, and biofilm action may, over time, compromise composite resin restorations. To reduce hybrid layer degradation by endogenous proteases and extend the longevity of resin restorations, MMP inhibitors and collagen cross-linking agents have been extensively studied. This work aims to identify, through a literature review, agents capable of inactivating MMPs at the dentin adhesive interface. This integrative review, based on studies retrieved from PUBMED/MEDLINE, LILACS, BBO, and VHL databases, identified 19 agents able to inhibit MMP activity at the adhesive-dentin interface in studies published between January 2018 and June 2023. It can be concluded that several agents can partially or completely block MMP activity, thereby enhancing restoration longevity. However, further studies are required to facilitate the clinical use of these agents, beyond chlorhexidine, in dental practice, with the application techniques suited to dentists’ daily clinical routines.

Short-Term Culture of Human Hyalocytes Retains Their Initial Phenotype and Displays Their Contraction Abilities

Background: Hyalocytes are the main vitreal cell types with critical functions in health and vitreoretinal diseases. Our aim was to develop cultures of human hyalocytes and verify the retention of their initial cellular features after 3 and 6 days of culturing (3 d and 6 d) by analyzing and comparing a few morphological and functional parameters. Methods: Vitreous samples (n = 22) were collected and vitreous cells and bead-enriched hyalocytes were developed and compared (3 d vs. 6 d cultures). Vitreous and conditioned media were tested for collagen, vascular endothelial growth factor (VEGF), transforming growth factor β1 (TGFβ1), nerve growth factor (NGF), matrix metalloproteinases (MMPs)/tissue inhibitors of metalloproteinases (TIMPs) and alpha-smooth muscle actin (αSMA) expression (ELISA, array/IP/WB, RT-PCR). Cells were observed at light and fluorescent microscopy (phenotypical properties) and tested for their 3D collagen gel contraction abilities. Results: An increased expression of collagens, vimentin, fibronectin, and the MMP9/TIMP1 ratio were observed in vitreous tissues. In 3 d cultures, collagens and MMP9 were upregulated while the related tissue-enzymes were deregulated. Vitreous samples also showed high levels of TGFβ1, VEGF, and NGF, and this protein signature was retained at 3 d while decreased at 6 d. The original phenotype (low αSMA) was retained at 3 d from seeding while an increased αSMA expression was observed at 6 d; NGF/trkANGFR was expressed in cultured hyalocytes and partially drives the collagen retraction. Conclusions: The vitreous print comparison between untouched and cultured hyalocytes allowed us, on one side, to select 3 d cultures and, on the other, to highlight the neuroprotective/contractile NGF in vitro hyalocytes effects. The possibility of scoring reactive hyalocytes would represent an interesting aspect of screening the vitreoretinal interface severity.

The therapeutic potential of PX-478 in a murine model of pelvic organ prolapse

Background Pelvic organ prolapse (POP), characterised by the downward displacement of pelvic organs, is a prevalent disorder that affects adult women. This study explored the therapeutic potential of PX-478, a selective hypoxia-inducible factor-1α (HIF-1α) inhibitor, in a murine POP model. Methods A murine POP model was established through ovariectomy, mimicking oestrogen deprivation. Fifteen C57BL/6J mice were randomly assigned to control, POP, and PX-478 groups. PX-478, targeting HIF-1α, was administered intravaginally. The analysis of fibroblasts, macrophage and inflammation was performed through Masson staining, immunofluorescence, and ELISA. Collagen distribution was assessed using Sirius Red staining. Expression levels of matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMP-1) were determined through immunohistochemistry and western blot. Fibroblast proliferation and apoptosis were evaluated by CCK-8 assay and flow cytometry. Results PX-478 treatment significantly reduced vaginal length, indicating a therapeutic effect on POP severity. Masson staining revealed reduced fibrotic changes and collagen disruption in PX-478-treated mice. Immunofluorescence showed increased fibroblast markers (Vimentin, α-SMA) and collagen fibres by PX-478. Sirius Red staining indicated PX-478 mitigated damage to Type I and Type III collagen fibres. PX-478 significantly reduced MMP-2 and MMP-9 expression while increased TIMP-1. In macrophages, PX-478 decreased M1 and M2 markers (CD80, CD206) and IL-18 secretion. Fibroblasts exhibited increased proliferation, reduced apoptosis, and altered MMP/TIMP expression under PX-478 influence. Conclusion PX-478 demonstrates a therapeutic potential in the mice POP model. It reduces vaginal length, attenuates fibrosis, and modulates collagen synthesis. Its immunomodulation is evident through reduced M1 and M2 macrophages and suppressed IL-18 secretion.

A comparative evaluation of the effect of matrix metalloproteinase inhibitor on the fracture resistance of endodontically treated teeth restored with Everstick-reinforced composite resin: An in vitro study

Aim: To evaluate the effect of applying a matrix metalloproteinase (MMP) inhibitor on the fracture resistance of root-filled teeth restored with Everstick fiber-reinforced composite resin. Subjects and Methods: After the selection of 60 freshly extracted human mandibular first molar, root canal access and standard uniformly sized mesio-occluso-distal (MOD) cavities were made and the teeth were randomly assigned into three groups (n = 20 each): Group I, the MOD cavity was first lined with flowable composite resin and then restored with composite resin. In Group II, Everstick fiber was placed into the bed of flowable composite in buccal–pulpal–lingual direction before the composite restoration was placed. In Group III, after etching of the cavity, a 2% chlorhexidine MMP inhibitor was applied. Then, the MOD cavity was restored same as group II. A universal testing machine was employed to compressively load the teeth at a cross-head speed of 0.5 mm/min till fracture. The maximum fracture loads were recorded in Newtons (N) and data were analyzed with one-way ANOVA and post-hoc Tukey tests. Results: Group III exhibited significantly higher fracture resistance compared to all other groups (P < 0.001), whereas Group I demonstrated the lowest fracture resistance. Conclusion: The utilization of Everstick glass fiber, combined with MMP inhibitor treatment, yielded the greatest fracture resistance. Hence, this method may be prioritized over conventional restoration techniques for strengthening root canal-treated teeth with structurally compromised crowns.

Diabetes mellitus exacerbates inflammation in a murine model of ligature-induced peri-implantitis: A histological and microtomographic study.

To investigate the influence of diabetes mellitus (DM) in a murine model of peri-implantitis (PI). Twenty-seven 4-week-old C57BL/6J male mice had their first and second maxillary left molars extracted. Eight weeks later, one machined implant was placed in each mouse. Four weeks after osseointegration, the mice were divided into three groups: (a) control (C), (b) PI and (c) DM + PI. DM was induced by streptozotocin (STZ) administration. After DM induction, PI was induced using ligatures for 2 weeks. The hemimaxillae were collected for micro-CT and histological analyses. The primary outcomes consisted of linear (mm) and volumetric (mm3) bone loss. Secondary outcomes were based on histological analysis and included inflammatory infiltrate, osteoclastic activity, matrix organization, composition and remodelling. Data are presented as means ± SEM. Statistical analyses were performed using one-way ANOVA, followed by Tukey's test. Gingival tissue oedema was detected in the PI and DM + PI groups. Micro-CT showed significantly increased linear and volumetric bone loss in the DM + PI group compared to the C and PI groups. H&E staining showed greater inflammatory response and bone resorption in the PI and DM + PI groups than in the C group. The DM + PI group had significantly higher osteoclast numbers than the C and PI groups. Picrosirius red stained less for types I and III collagen in the PI and DM + PI groups than in the C group. There was a significant increase in monocyte/macrophage (CD-11b) counts and matrix metalloproteinases (MMP-2 and MMP-8) marker levels and a significant decrease in the matrix metalloproteinases inhibition marker (TIMP-2) levels in the DM + PI group compared to the C and PI groups. DM exacerbates PI-induced soft-tissue inflammation, matrix degradation and bone loss.

Effect of mesenchymal stem cell derived from umbilical cord blood on rabbit intrauterine adhesion model

Objective: To investigate the repair effect of human umbilical cord blood mesenchymal stem cells (hUCB-MSC) on endometrium of intrauterine adhesion (IUA) by establishing animal model. Methods: Eighteen healthy female New Zealand white rabbits were divided into a control group, an IUA group and an hUCB-MSC transplantation group according to random number table method. The control group underwent laparotomy only. The IUA group underwent IUA modeling surgery using curettage and lipopolysaccharide (LPS) cotton placed in uterine cavity for double injury. The hUCB-MSC transplantation group received the same IUA modeling surgery followed by multipoint injection of hUCB-MSC suspension (2×106 cells/ml, 500 μl) into the bilateral uterine myometrium one week after surgery. Four weeks after the IUA modeling surgery, the rabbits were euthanized and samples were collected. Hematoxylin and eosin (HE) staining and Masson staining were used to assess the number of endometrial glands and the fibrosis rate. RNA sequencing was performed on the endometrium of the IUA group and hUCB-MSC transplantation group.The mRNA and protein expression of the fibrosis markers [transforming growth factor β1 (TGF-β1) and tissue inhibitors of metalloproteinase 1 (TIMP1)] and RNA sequencing-related parameters were detected by quantitative real-time PCR (qRT-PCR) and Western blot. Results: Compared with the control group, the number of glands in IUA group decreased (26.33±1.53 vs 4.33±1.53, P<0.001), and the fibrosis rate increased (18.01%±2.21% vs 69.55%±2.42%, P<0.001), indicating successful modeling. HE and Masson staining revealed that the number of glands in the hUCB-MSC transplantation group was increased compared with that in IUA group (17.33±2.52 vs 4.33±1.53, P<0.001), and the fibrosis rate decreased (69.55%±2.42% vs 41.55%±1.99%,P=0.001). Western blot analyses of fibrosis-related proteins (TGF-β1 and TIMP1) showed elevated levels of TGF-β1 (0.91±0.05) and TIMP1 (0.99±0.01) proteins in the IUA group compared to control group (0.61±0.04, 0.68±0.07) (P=0.001, 0.015). The hUCB-MSC transplantation group exhibited reduced expression of TGF-β1 (0.69±0.04) and TIMP1 (0.62±0.08) proteins compared to the IUA group (P=0.005, 0.014). Western Blot results related to the PI3K/AKT signaling pathway [phosphorylated phosphatidylinositol 3-kinase (p-PI3K), phosphorylated protein kinase B (p-AKT)] showed that the expression of p-PI3K(1.05±0.05) and p-AKT(1.17±0.06) in the IUA group increased compared to the control group (0.78±0.03, 0.85±0.05) (P=0.002, 0.002). The expression of p-PI3K (0.74±0.02) and p-AKT (0.93±0.04) proteins in the hUCB-MSC transplantation group decreased compared to the IUA group (P=0.003, 0.005). Conclusion: hUCB-MSC can repair the damaged endometrium in rabbit intrauterine adhesion model by increasing the number of endometrial glands and improving its level of fibrosis.

The circRNA circSCAF8 promotes tumor growth and metastasis of gastric cancer via miR-1293/TIMP1signaling.

SR-like CTD-associated factor 8 (SCAF8) can regulate transcriptional termination, but the function of circSCAF8 remains unclear. In our study, we observed a significant increase in circSCAF8 expression in gastric cancer, particularly in tissues with lymph node metastasis. The Kaplan-Meier curve revealed that high circSCAF8 expression was associated with a low overall survival time in gastric cancer patients. Moreover, circSCAF8 shRNA effectively decreased gastric cancer proliferation, invasion, and migration in vitro. Additionally, using bioluminescence imaging (BLI) technology in vivo, we found that circSCAF8 shRNA viruses inhibited the growth of xenograft tumors and gastric cancer lung metastasis. RNA immunoprecipitation (RIP) and circRNA pulldown assays confirmed the direct binding of circSCAF8 to miR-1293, but circSCAF8 could not regulate the expression of miR-1293 in gastric cancer. Interestingly, circSCAF8 regulated the downstream gene tissue inhibitor of metalloproteinases 1 (TIMP1) of miR-1293, and this observation was further verified in gastric cancer tissues. Moreover, we confirmed that miR-1293 directly suppressed TIMP1 expression. Subsequent rescue experiments revealed that TIMP1 overexpression reversed the impact of circSCAF8 shRNA viruses on gastric cancer. In conclusion, circSCAF8 expression was elevated in gastric cancer, and circSCAF8 shRNA viruses inhibited gastric cancer growth and metastasis by upregulating TIMP1 expression via miR-1293.

Polygenic proxies of age-related plasma protein levels reveal TIMP2 role in cognitive performance.

Background While numerous studies have identified blood proteins that modulate brain aging in mice, the direct translation of these findings to human health remains a substantial challenge. Bridging this gap is critical for developing interventions that can effectively target human brain aging and associated diseases. Methods We first identified 12 proteins with aging or rejuvenating properties in murine brains through a systematic review. Using protein quantitative trait loci data for these proteins, we developed polygenic scores to predict plasma protein levels, which we then validated in two independent human cohorts. We employed association models to explore the association between these genetically predicted protein levels and cognitive performance, focusing specifically on their interaction with key genetic markers such as sex, APOE -ε4 and Aβ42 status. Results Predicted plasma levels of Tissue Inhibitor of Metalloproteinases 2 (TIMP2) were significantly associated with improved global cognition and memory performance in humans, also when the models were stratified by sex, APOE -ε4, and Aβ42 status. Conclusions This finding aligns with TIMP2's brain-rejuvenating role in murine models, suggesting it as a promising therapeutic target for brain aging and age-related brain diseases in humans.

Genetic removal of Nlrp3 protects against sporadic and R345W Efemp1-induced basal laminar deposit formation.

Chronic, unresolved inflammation has long been speculated to serve as an initiating and propagating factor in numerous neurodegenerative diseases, including a leading cause of irreversible blindness in the elderly, age-related macular degeneration (AMD). Intracellular multiprotein complexes called inflammasomes in combination with activated caspases facilitate production of pro-inflammatory cytokines such as interleukin 1 beta. Specifically, the nucleotide-binding oligomerization (NOD)-like receptor protein 3 (NLRP3) has received heightened attention due to the wide range of stimuli to which it can respond and its potential involvement in AMD. In this study, we directly tested the role of Nlrp3 and its downstream effector, caspase 1 (Casp1) in mediating early AMD-like pathology (i.e., basal laminar deposits [BLamDs]) in wild-type (WT) mice and the Malattia Leventinese/Doyne honeycomb retinal dystrophy (ML/DHRD) mouse model (p.R345W mutation in Efemp1). Compared to aged-matched controls, R345W +/+ knockin mice demonstrated increased Muller cell gliosis, subretinal Iba-1 + microglial cells, higher Nlrp3 immunoreactivity in the retina, as well as significant transcriptional upregulation of complement component 3, Nlrp3, pro-Il1b, pro-caspase-1, and tissue inhibitor of matrix metalloproteinase 3 in the retinal pigmented epithelium (RPE)/choroid. These findings were accompanied by an age-related increase in BLamD formation in the R345W +/+ mice. Genetic elimination of either Nlrp3 or Casp1 significantly reduced both the size and coverage of BLamDs in the R345W +/+ background, highlighting an important and underappreciated pathway that could affect ML/DHRD onset and progression. Moreover, Nlrp3 knockout reduced spontaneous, idiopathic BLamDs in WT mice, suggesting translatability of our findings not only to rare inherited retinal dystrophies, but also potentially to AMD itself.

Role of MMP-2, MMP-9, TIMP-1, and TIMP-2 in children with ventricular septal defect.

Ventricular septal defect (VSD) is the second most common congenital heart anomaly. In most cases, it closes spontaneously in the first year of life, but it sometimes requires surgical closure due to the risk of serious complications. This is why it is important to identify markers that could help predict its course. Findings that matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) play an important role in the cleavage of the extracellular matrix were the reasons to investigate their role in cardiogenesis.In prior studies on this topic, their concentrations were studied in the blood.The aim of this prospective study was to investigate the role of MMP-2, MMP-9, TIMP-1, and TIMP-2 in the etiology and pathophysiology of VSD using urine samples, as an innovative non-invasive approach, and the ELISA method. It involved fifty-two children with isolated VSD and twenty healthy children up to one year of age. We found that these MMPs and TIMPs are significantly (P = 0.000) higher in children with VSD, and the correlations between their concentrations and the size of the defect are positive, especially for MMP-9 and TIMP-1. MMP-9 was significantly (P = 0.044) higher in cases in which VSD didn't close in the first year of life compared to cases in which it closed. Our results suggest the role of MMP-2, MMP-9, TIMP-1, and TIMP-2 in the aetiopathogenesis of VSD and that their urinary concentrations, especially of MMP-9, in combination with echocardiographic and clinical monitoring, could be useful in predicting its natural course.

The effect of consuming a sucrose-containing sports drink on acute kidney injury risk during a four-hour simulated occupational heat stress.

Occupational heat stress increases acute kidney injury risk. Drinking a soft drink sweetened with high fructose corn syrup further elevates this acute kidney injury risk. However, the impact of sucrose, another fructose containing-sweetener, on acute kidney injury risk remains unexplored. We tested the hypothesis that drinking a sucrose-containing sports drink increases acute kidney injury risk when compared to drinking a sugar-free sports drink during four hours of simulated occupational heat stress. Ten healthy adults consumed a sucrose-containing or sugar-free sport drink ad libitum during four-hour exposures to wet bulb globe temperatures of ~28°C. 30 min of work and 30 min of rest were completed each hour. Work involved treadmill walking at a fixed rate of metabolic heat production (sucrose-containing: 6.0±1.2 W/kg, sugar-free: 5.5±0.9 W/kg, p=0.267). The product of urinary insulin-like growth factor-binding protein 7 and tissue inhibitor of metalloproteinase-2, normalized to urine specific gravity ([IGFBP7·TIMP-2]USG), provided an acute kidney injury risk index. Mean core (intestinal: n=13, rectal: n=7) temperature (sucrose-containing: 37.5±0.1°C, sugar-free: 37.5±0.3 °C; p=0.914), peak core temperature (sucrose-containing: 37.8±0.2°C, sugar-free: 37.9±0.3 °C; p=0.398), and percent changes in body mass (sucrose-containing: -0.5±0.4%, sugar-free: -0.3±0.6%; p=0.386) did not differ between groups. [IGFBP7∙TIMP-2]USG increased in both groups (time effect: p=0.0254) with no drink (p=0.675) or interaction (p=0.715) effects. Peak change [IGFBP7∙TIMP-2]USG did not differ between sucrose-containing (median 0.0116 [-0.0012, 0.1760] (ng/mL)²/1000) and sugar-free (median 0.0021 [0.0003, 0.2077] (ng/mL)²/1000; p=0.796). Sucrose-containing sports drink consumption during simulated occupational heat stress does not modify acute kidney injury risk when compared to sugar free-sport drink consumption.

Results of surgical treatment of chronic pancreatitis with a high risk of developing pancreatic cancer

Objective. To analyze the results of surgical treatment of patients with pancreatic insufficiency and a high risk of developing pancreatic cancer. Materials and methods. The study included 39 patients treated in 2019–2023. In 20 (51%) patients, it was difficult to clearly differentiate between chronic pancreatitis and pancreatic cancer. In 19 (49%) patients, the diagnosis of chronic pancreatitis was not in doubt. All patients with complicated forms of chronic pancreatitis and suspected pancreatic tumor underwent a set of laboratory tests, and routine screening methods of instrumental diagnostics were used. In addition to standard methods of examination, the levels of matrix metalloproteinases and tissue inhibitor of metalloproteinases in the blood plasma were studied. Results. The method of intraoperative multiple biopsy, improved by us, was an obligatory component of surgical care for a clear differential diagnosis of chronic pancreatitis and pancreatic cancer. In the presence of complicated chronic pancreatitis, during surgery, the biopsy was taken using a special punch instrument that resembles a pen, along the entire length of the main pancreatic duct along the upper and lower edges of the dissection in a checkerboard pattern. There were no complications of punch biopsy. Of the 20 patients in whom it was not possible to clearly differentiate between chronic pancreatitis and pancreatic cancer, 12 (60%) were diagnosed with diabetes mellitus. The characteristic changes in the pancreatic tissue gave grounds for performing extended resection interventions in these patients. In the remaining 8 (40%) patients without morphological changes inherent in malignancy, Whipple operation (2), longitudinal pancreaticoduodenectomy (2), Frey operation (2), and our proposed central pancreatic resection with preservation of the left anatomical segment (2) were performed. Drainage and resectional surgical interventions were performed in 19 (49%) patients with complicated forms of chronic pancreatitis. After radical surgical interventions for pancreatic cancer, 1 patient developed gastrostasis, and on the 11th day he underwent a relaparotomy with reconstruction of the gastroenteroanastomosis, and on the 30th day a subhepatic abscess was diagnosed in 1 patient, who underwent drainage with a subcostal mini–access with a positive effect. In 2 patients, after left–sided pancreatic resection, subdiaphragmatic abscesses were diagnosed on the left, they were treated minimally invasively with punctures and drainage under ultrasound control. Multiple organ failure occurred in 1 patient after surgery for internal pancreatic fistula, infected ascites as a complication of neglected chronic pancreatitis. The patient died. Infection of the median laparotomy wound occurred in 4 patients, and healing was achieved by controlled primary tension. Class B pancreatic fistulas occurred in 3 patients: 2 – after left–sided pancreatic resection, 1 – after longitudinal pancreaticoduodenostomy. In 1 patient, a class C permanent pancreatic fistula was formed after a combined (resection and drainage) intervention. Relaparotomy, subtotal resection with Roux–en–Y loop closure was performed. Conclusions. Morphological changes in the pancreatic tissue in chronic pancreatitis in combination with diabetes mellitus, corresponding to the development of PanIN, are direct predictors of adenocarcinoma. Multiple intraoperative pancreatic biopsies are effective in verifying pancreatic malignancy. Pre– and intraoperative diagnostics make it possible to optimize the surgical treatment of complicated forms of chronic pancreatitis and prevent the development of postoperative pancreatic fistula.

Exosomal therapy mitigates silver nanoparticles-induced neurotoxicity in rats

Introduction Our investigation aims to appraise the neuroprotective impact of Bone Marrow-Mesenchymal Stem Cells (BM-MSCs) derived exosomes against Ag NPs-inducing neurotoxicity in rats. Materials and Methods Twenty-four albino rats were divided into 3 groups. Group I (control negative), Group II (intraperitoneally injected with Ag NPs for 28 days, whereas Group III (intraperitoneally injected with Ag NP and BM-MSCs derived exosomes. Results There was a marked elevation of Malondialdehyde (MDA) along with a reduction of brain antioxidants, Gamma-aminobutyric acid (GABA) and Monoamine Oxidase (MAO) in the Ag NPs receiving group. Ag NPs upregulated c-Jun N-terminal Kinases (JNK) genes and c-Myc and downregulated the tissue inhibitors of metalloproteinases (TIMP-1) and Histone deacetylase 1 (HDAC1) genes. Otherwise, the co-treatment of BM-MSCs derived exosomes with Ag NPs could markedly increase the rat’s body weight, activity and learning while, decreasing anxiety, restoring all the toxicological parameters and improving the microscopic appearance of different brain areas. Conclusion BM-MSCs-derived exosomes downregulated both apoptotic and inflammatory mediators and upregulated the antiapoptotic genes. BM-MSCs-derived exosomes exhibit a great therapeutic effect against the neurotoxic effects of Ag NPs.

Clinical and morphological features of the myometrium in patients with placental adherent and invasive pathology

BACKGROUND: The fast increase in the frequency of placental adherent and invasive pathology worldwide accounts for the growing interest in studying the pathogenesis of placenta accreta. According to the literature, the clinical and morphological features of the myometrium from the placental attachment area in placental adherent and invasive pathology are described in single articles. Study of morphological features using proteolytic markers in the myometrium from the placenta accreta area could help in understanding the pathogenesis of placental adherent and invasive pathology. For the first time in this study, the clinical and morphological features of the myometrium from the placental attachment area in patients with uterine scar and placental adherent and invasive pathology are compared with the myometrium of women with uterine scar without placenta accreta and intact myometrium. AIM: The aim of this study was to evaluate the expression of matrix metalloproteinase 2 and tissue inhibitors of matrix metalloproteinases 1 and 2 in myometrial biopsies in placental adherent and invasive pathology. MATERIALS AND METHODS: This study included 15 myometrial biopsies from the placental site, which were divided into three groups according to the clinical diagnosis of the patients: group 1 (main group), with a uterine scar after cesarean section and placental adherent and invasive pathology (n = 5); group 2 (comparison group), with a uterine scar after cesarean section (n = 5); group 3 (control group), with a normal pregnancy without a uterine scar (n = 5). Histological examination was carried out using the standard procedure. Immunohistochemical study was performed using antibodies to matrix metalloproteinase 2 and tissue inhibitors of matrix metalloproteinases 1 and 2 (Abcam, USA). Morphometry was carried out using the VideoTesT-Morphology 5.2 program (Videotest Ltd., Russia). The statistical analysis was performed using the IBM SPSS Statistics 26.0 software. RESULTS: In the biopsies of the main group, we verified terminal chorionic villi with hypervascularization and uneven plethora of the vascular bed among hypertrophied muscle fibers, a basal plate with lumen ectasia of unevenly full-blooded vessels, and the absence of a decidual membrane, in contrast to groups 2 and 3. The matrix metalloproteinase 2 expression area in the main group was higher than in the comparison and control groups (p = 0.008; p1–2 = 0.049*, p1–3 = 0.011), the matrix metalloproteinase 2 optical density not differing between the groups (p = 0.122). The tissue inhibitors of matrix metalloproteinases 1 expression area was higher in the comparison group compared to the main group (p = 0.035; p2–3 = 0.032), and the tissue inhibitors of matrix metalloproteinases 1 and 2 optical density was higher in the comparison group compared to control (p = 0.008; p2–3 = 0.005). CONCLUSIONS: In myometrial biopsies of patients with a uterine scar and placental adherent and invasive pathology, we verified pathology of the basal plate of the placenta, increased matrix metalloproteinase 2 expression and decreased tissue inhibitors of matrix metalloproteinases 1 expression, which may indicate the peculiarities of the inflammatory response in the myometrium in placental adherent and invasive pathology.

Bone and periosteum protein analysis via tandem mass tag quantitative proteomics in pediatric patients with osteomyelitis.

Bone healing is crucial in managing osteomyelitis after fracture fixation. Understanding the mechanism of extensive callus formation in pediatric osteomyelitis is highly important. This study aims to analyze bone and periosteum samples from pediatric patients to elucidate the essential processes involved in callus formation during osteomyelitis. The study included eight patients from our hospital: four with positive microbial culture who underwent osteomyelitis debridement and four who had osteotomy surgery as contral. We used tandem mass tag quantitative proteomics to investigate proteomic changes in bone and periosteum tissues obtained from these patients. Differential expression proteins were analyzed for their pathways through Gene Ontology (GO) annotation, GO enrichment analysis, Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis, and protein-protein interaction networks. A total of 4737 proteins were successfully identified. About 2224 differentially expressed proteins were detected in the bone tissues group and periosteum tissues group. Among the differentially expressed proteins, 10 protein genes in the bone group were associated with inflammation and osteogenesis, while in the periosteum group were nine. Cytochrome b-245, beta polypeptide (CYBB), nicotinamide phosphoribosyltransferase (NAMPT), tissue inhibitor of metalloproteinases 1 (TIMP-1), Raf-1 proto-oncogene, serine/threonine kinase (RAF-1), RELA proto-oncogene, NF-KB subunit (RELA), and sphingomyelin synthase 2 (SGMS2) may play an important role in callus formation in patients with osteomyelitis. This study provides novel clues for understanding callus formation in pediatric patients with osteomyelitis.

Modification of transvaginal polypropylene mesh with co-axis electrospun nanofibrous membrane to alleviate complications following surgical implantation

BackgroundSurgeries for treating pelvic organ prolapse involving the utilization of synthetic mesh have been associated with complications such as mesh erosion, postoperative pain, and dyspareunia. This work aimed to reduce the surgical implantation-associated complications by nanofibrous membranes on the surface of the polypropylene mesh. The nanofiber of the nanofibrous membrane, which was fabricated by co-axial electrospinning, was composed of polyurethane as fiber core and gelatin as the fiber out layer. The biocompatibility of the modified mesh was evaluated in vitro by cell proliferation assay, immunofluorescence stain, hematoxylin-eosin (HE) staining, and mRNA sequencing. Polypropylene mesh and modified mesh were implanted in a rat pelvic organ prolapse model. Mesh-associated complications were documented. HE and Picro-Sirius red staining, immunohistochemistry, and western blotting were conducted to assess the interactions between the modified mesh and vaginal tissues.ResultsThe modified mesh significantly enhanced the proliferation of fibroblasts and exerted a positive regulatory effect on the extracellular matrix anabolism in vitro. When evaluated in vivo, no instances of mesh exposure were observed in the modified mesh group. The modified mesh maintained a relatively stable histological position without penetrating the muscle layer or breaching the epidermis. The collagen content in the vaginal wall of rats with modified mesh was significantly higher, and the collagen I/III ratio was lower, indicating better tissue elasticity. The expression of metalloproteinase was decreased while the expression levels of tissue inhibitor of metalloproteinase were increased in the modified mesh group, suggesting an inhibition of collagen catabolism. The expression of TGF-β1 and the phosphorylation levels of Smad3, p38 and ERK1/2 were significantly increased in the modified mesh group. NM significantly improved the biocompatibility of PP mesh, as evidenced by a reduction in macrophage count, decreased expression levels of TNF-α, and an increase in microvascular density.ConclusionsThe nanofibrous membrane-coated PP mesh effectively reduced the surgical implantation complications by inhibiting the catabolism of collagen in tissues and improving the biocampibility of PP mesh. The incorporation of co-axial fibers composed of polyurethane and gelatin with polypropylene mesh holds promise for the development of enhanced surgical materials for pelvic organ prolapse in clinical applications.

A murine experimental model of the pulmonary thrombotic effect induced by the venom of the snake Bothrops lanceolatus.

The venom of Bothrops lanceolatus, a viperid species endemic to the Lesser Antillean Island of Martinique, induces thrombosis in a number of patients. Previous clinical observations indicate that thrombotic events are more common in patients bitten by juvenile specimens. There is a need to develop an experimental model of this effect in order to study the mechanisms involved. The venoms of juvenile and adult specimens of B. lanceolatus were compared by (a) describing their proteome, (b) assessing their ability to induce thrombosis in a mouse model, and (c) evaluating their in vitro procoagulant activity and in vivo hemostasis alterations. Venom proteomes of juvenile and adult specimens were highly similar, albeit showing some differences. When injected by the intraperitoneal (i.p.) route, the venom of juvenile specimens induced the formation of abundant thrombi in the pulmonary vasculature, whereas this effect was less frequent in the case of adult venom. Thrombosis was not abrogated by the metalloproteinase inhibitor Batimastat. Both venoms showed a weak in vitro procoagulant effect on citrated mouse plasma and bovine fibrinogen. When administered intravenously (i.v.) venoms did not affect classical clotting tests (prothrombin time and activated partial thromboplastin time) but caused a partial drop in fibrinogen concentration. The venom of juvenile specimens induced partial alterations in some rotational thromboelastometry parameters after i.v. injection. When venoms were administered i.p., only minor alterations in classical clotting tests were observed with juvenile venom, and no changes occurred for either venom in rotational thromboelastometry parameters. Both juvenile and adult venoms induced a marked thrombocytopenia after i.p. injection. An experimental model of the thrombotic effect induced by B. lanceolatus venom was developed. This effect is more pronounced in the case of venom of juvenile specimens, despite the observation that juvenile and adult venom proteomes are similar. Adult and juvenile venoms do not induce a consumption coagulopathy characteristic of other Bothrops sp venoms. Both venoms induce a conspicuous thrombocytopenia. This experimental model reproduces the main clinical findings described in these envenomings and should be useful to understand the mechanisms of the thrombotic effect.

Protein Kinase C and Matrix Metalloproteinases Expression Using Phorbol Myristate Acetate in Degenerative Intervertebral Disc Cells.

Degeneration of nucleus pulposus (NP) cells involves multiple factors. The relationship between the canonical Wnt/β-catenin signaling pathway and matrix metalloproteinases (MMPs) is important in cellular senescence. Protein kinase C (PKC), an intermediate of the non-canonical Wnt pathway stimulated by phorbol myristate acetate (PMA), possibly prevents NP cell senescence, although not yet demonstrated in human-based studies. This study aimed to investigate the effect of PMA stimulation on the non-canonical and canonical Wnt pathways and MMP expression in human NP cells to ascertain its inhibitory effects on the senescence of NP cells. Human disc tissues of Pfirrmann grades 1 and 2 were collected from patients during spinal surgery and subsequently cultured. Protein and ribonucleic acid (RNA) were isolated from NP cells treated with PMA (400 nM) for 24 hours. Expression of MMP1, MMP13, tissue inhibitor of matrix metalloproteinase 1 (TIMP1), a disintegrin and metalloproteinase with thrombospondin motifs 5 (ADAMTS5), transient receptor potential vanilloid 4 (TRPV4), interleukin-6 (IL-6), and β-catenin were detected using western blot analysis. Messenger RNA (mRNA) expression of type II collagen and glycosaminoglycan (GAG) were analyzed using reverse transcription polymerase chain reaction. IL-6 and prostaglandin E2 (PGE2) levels were measured using enzyme-linked immunosorbent assay. Expression of PKC-δ (intermediate of the non-canonical Wnt pathway) and β-catenin (intermediate of the canonical Wnt pathway) was increased by PMA treatment. The mRNA levels of type II collagen and GAG increased; however, their protein levels were not altered. PMA treatment increased the expression of MMP1, TIMP1, ADAMTS5, IL-6, PGE2, and TRPV4; however, the expression of MMP13 and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) was unaltered. PMA activated PKC-δ, affecting the non-canonical Wnt pathway; however, its effect on β-catenin in the canonical Wnt pathway was limited. β-catenin activation through the TRPV4 channel led to increased expression of MMP1 and ADAMTS5 and that of IL-6 and PGE2 owing to NF-κB expression. Consequently, the degeneration of NP cells was not prevented.