Hydroxyproline Research Articles

Total alkaloids of bulbus of Fritillaria cirrhosa alleviate bleomycin-induced inflammation and pulmonary fibrosis in rats by inhibiting TGF-β and NF-κB signaling pathway.

Bulbus of Fritillaria cirrhosa is a medicinal and edible plant that has the functions of clearing away heat and moisturizing the lungs, resolving phlegm, and relieving coughs. Its ethanol extract has been proven to have a therapeutic effect on lung diseases. Pulmonary fibrosis is a respiratory disease that forms scars in lung tissue, leading to severe respiratory problems. However, the therapeutic effect of total alkaloids of bulbus of Fritillaria cirrhosa (BFC-TA) on pulmonary fibrosis has not been confirmed. This study aimed to investigate the therapeutic effect of total alkaloids of Fritillaria cirrhosa on pulmonary fibrosis rat model and explore its potential mechanism. The total alkaloids in the bulbus of Fritillaria cirrhosa were purified using cation exchange resin. The alkaloids contained in the BFC-TA were identified, and the concentration of alkaloids was determined by High Performance Liquid Chromatography-Diode Array Detector-Evaporative Light Scattering Detector (HPLC-DAD-ELSD). Bleomycin (BLM) (5.0 mg/kg) was instilled into the trachea of 60 rats to establish a pulmonary fibrosis model. After 7 days, BFC-TA (34.2, 68.4, and 136.8 mg/kg) was administered continuously for 21 days. During this period, the body weight changes of the rats were measured, the levels of hydroxyproline (HYP) and inflammatory factors were measured in the collected serum, and the histological analysis of the lung tissue was performed by staining technology. Western blotting and quantitative Polymerase Chain Reaction (qPCR) were used to assess the protein and gene composition of inflammation and transforming growth factor-β (TGF-β) signaling pathways. Nine main components (Peimisine, Imperialine-3-β-D-glucoside, Yibeinoside A, Imperialine, Peiminine, Isopeimine, Hupehenine, Delavinone, Ebeiedinone) were determined by HPLC-DAD-ELSD, and the contents of Peimisine, Imperialine-3-β-D-glucoside and Imperialine were determined. BFC-TA (34.2, 68.4, and 136.8 mg/kg) reduced the levels of pro-inflammatory factors, increased the levels of anti-inflammatory factors, dose-dependently improved the morphology of lung tissue. And during epithelial-mesenchymal transition process, BFC-TA dose-dependently reduced the expression of E-cadherin, dose-dependently increased the expression of Fibronectin. In addition, Western blot analysis and qPCR results showed that inhibiting NF-κB and TGF-β-related signaling pathways effectively slowed down the occurrence of BLM-induced pulmonary fibrosis in rats. And the therapeutic effect of BFC-TA (136.8 mg/kg) is better than that of pirfenidon (PFD) (150 mg/kg). BFC-TA effectively alleviates the progression of the BLM-induced pulmonary fibrosis rat model by regulating the inflammatory response in the lungs and the expression of the TGF-β signaling pathway.

Regulation of miRNA-155-5p ameliorates NETosis in pulmonary fibrosis rat model via inhibiting its target cytokines IL-1β, TNF-α and TGF-β1

Idiopathic pulmonary fibrosis (IPF) is an age-related inflammatory disease with no cure up till now.It is accompanied by neutrophils infiltration as the main responders to inflammation and fibrosis. Importantly, neutrophils release neutrophil extracellular traps (NETs) through NETosis process. The function of microRNAs during inflammation became of great biological attention. Owing to microRNAs’ central role in immune system, microRNA-155-5p (miR-155-5p) is intensely involved in the inflammatory response. Capsaicin (Cap) is a bioactive compound that exhibits antioxidative and anti-inflammatory functions. Recent studies have shown its role in regulation of certain microRNAs’ expressions. Accordingly, the present study aims to investigate the effect of miR-155-5p regulation in suppressing NETs production via ameliorating its target inflammatory cytokines, IL-1ß, TNF-α and TGF-ß1, in bleomycin (BLM)-induced pulmonary fibrosis rat model treated by Cap. The obtained results demonstrated that miR-155-5p downregulation was associated with significant decrease in IL-1ß, TNF-α, TGF-β1, which consequently, reduced hydroxyproline (HYP), NETs activity markers as NE and PAD-4, and alleviated CTGF levels in lung tissues of animals treated by Cap. Furthermore, NETosis ultrastructure examination by transmission electron microscope (TEM), MPO immunohistochemical staining and histopathological studies confirmed an abolishment in NETs formation and an improvement in lung tissue architecture in Cap-treated rats. This study concluded that Cap quenched the inflammatory response through interrupting IL-1β, TNF-α and TGF-β1 pathway via modulating miR-155-5p expression. In addition, Cap was able to alleviate pulmonary NETosis markers by restraining NETs activity markers. These findings provide novel insight into the application of Cap-based treatment in ameliorating pulmonary damage in IPF.

Protective effect and mechanism of Maiwei Yangfei Decoction on pulmonary fibrosis mice based on Nrf2 regulation of oxidative stress

This study explored the effect and mechanism of Maiwei Yangfei Decoction(MWYF) on pulmonary fibrosis(PF) mice. MWYF was prepared, and its main components were detected by ultra-high-performance liquid chromatography-triple quadrupole tandem mass spectrometry(UPLC-MS/MS). Male C57BL/6J mice were randomly divided into a control group, a model group, a pirfenidone(PFD) group, and low-, medium-, and high-dose MWYF groups, with 10 mice in each group. The PF model was induced in mice except for those in the control group by intratracheal instillation of bleomycin(BLM), and model mice were treated with saline or MWYF or PFD by gavage the next day. The water consumption, food intake, hair, and activity of mice were observed daily. The pathological changes in lung tissues were observed by hematoxylin-eosin(HE) staining, Masson staining, and CT scanning. The level of hydroxyproline(HYP) in lung tissues was detected by alkaline hydrolysis. Immunohistochemistry was used to observe the expression of collagen type Ⅲ(COL3) and fibronectin. The mRNA expression levels of α-smooth muscle actin(α-SMA), type Ⅰ collagen α1(COL1α1), COL3, and vimentin were detected by reverse transcription real-time fluorescence quantitative polymerase chain reaction(RT-qPCR). Superoxide dismutase(SOD) and malondialdehyde(MDA) kits were used to detect oxidative stress indicators in lung tissues and serum. The nuclear translocation of nuclear factor E2-related factor 2(Nrf2) protein was detected by immunofluorescence. The protein and mRNA expression levels of Nrf2, catalase(CAT), and heme oxygenase 1(HO-1) in lung tissues were detected by Western blot and RT-qPCR. Twelve chemical components were detected by UPLC-MS/MS. Animal experiments showed that MWYF could improve alveolar inflammation, collagen deposition, and fibrosis in PF mice, increase body weight of mice, and down-regulate the expression of fibrosis indexes such as HYP, α-SMA, COL1α1, COL3, fibronectin, and vimentin in lung tissues. In addition, MWYF could potentiate the activity of SOD in lung tissues and serum of PF mice, up-regulate the expression level of Nrf2, and promote its transfer to the nucleus, up-regulate the levels of downstream antioxidant target genes CAT and HO-1, and then reduce the accumulation of lipid metabolite MDA. In summary, MWYF can significantly improve the pathological damage and fibrosis of lung tissues in PF mice, and its mechanism may be related to the activation of the Nrf2 pathway to regulate oxidative stress.

Luteolin alleviates renal ischemia-reperfusion injury in streptozotocin induced diabetic rats by inhibiting metalloenzymes expression

Abstract Diabetes patients are more prone to acute kidney injury (AKI). Endopeptidases known as matrix metalloproteinases (MMPs) cause extracellular matrix destruction and are responsible for ischemic organ damage. Diabetic nephropathy (DN) affects almost one third of all diabetic patients. MMP-2 and MMP-9 lead to the breakdown of the basement membrane of the glomeruli and thereby the advancement of ischemic injury in diabetes. In addition, histone deacetylase-2 (HDAC-2) is the primary regulator of important signalling processes in the diabetic kidney. A possible treatment approach for diabetic kidney preservation is the flavonoid luteolin (LT), which has anti-inflammatory and antioxidant effects. Our aim was to investigate the renoprotective potential of LT in diabetes by modulating MMP-2, MMP-9 and HDAC-2 activity. The expression of MMP-2, MMP-9 and HDAC-2 were statistically higher in streptozotocin-induced diabetic rat renal homogenate after renal ischemic reperfusion injury. These changes were reversed with 2 weeks of pre-treatment with LT (50 mg/kg po). In diabetic rats, pre-treatment with LT significantly reduced oxidative stress, inflammation and fibrosis compared to control animals. Preventive LT prior to renal ischemia showed improvement in body weight, kidney weight/body weight ratio, reversal of renal injury and biochemical changes with lower activity of malondialdehyde (MDA), myeloperoxidase (MPO), hydroxyproline (HP), pathological damage and fibrosis in renal tissue. Our data imply that LT prevents DN in rats by inhibiting MMP-2, MMP-9 and HDAC-2 expression, as well as by lowering the indices of oxidative stress, pro-inflammatory factors and fibrosis.

Induced pluripotent stem cells modulate the Wnt pathway in the bleomycin-induced model of idiopathic pulmonary fibrosis

BackgroundThe Wnt signaling pathway has been implicated in the pathogenesis of fibrotic disorders and malignancies. Hence, we aimed to assess the potential of the induced pluripotent stem cells (IPS) in modulating the expression of the cardinal genes of the Wnt pathway in a mouse model of idiopathic pulmonary fibrosis (IPF).MethodsC57Bl/6 mice were randomly divided into three groups of Control, Bleomycin (BLM), and BLM + IPS; the BLM mice received intratracheal instillation of bleomycin, BLM + IPS mice received tail vein injection of IPS cells 48 h post instillation of the BLM; The Control group received Phosphate-buffered saline instead. After 3 weeks, the mice were sacrificed and Histologic assessments including hydroxy proline assay, Hematoxylin and Eosin, and Masson-trichrome staining were performed. The expression of the genes for Wnt, β-Catenin, Lef, Dkk1, and Bmp4 was assessed utilizing specific primers and SYBR green master mix.ResultsHistologic assessments revealed that the fibrotic lesions and inflammation were significantly alleviated in the BLM + IPS group. Besides, the gene expression analyses demonstrated the upregulation of Wnt, β-Catenin, and LEF along with the significant downregulation of the Bmp4 and DKK1 in response to bleomycin treatment; subsequently, it was found that the treatment of the IPF mice with IPS cells results in the downregulation of the Wnt, β-Catenin, and Lef, as well as upregulation of the Dkk1, but not the Bmp4 gene (P values < 0.05).ConclusionThe current study highlights the therapeutic potential of the IPS cells on the IPF mouse model in terms of regulating the aberrant expression of the factors contributing to the Wnt signaling pathway.

Stevioside attenuates bleomycin-induced pulmonary fibrosis by activating the Nrf2 pathway and inhibiting the NF-κB and TGF-β1/Smad2/3 pathways

Objective: This study aimed to investigate the effects of stevioside (STE) on pulmonary fibrosis (PF) and the potential mechanisms. Methods: In this study, a mouse model of PF was established by a single intratracheal injection of bleomycin (BLM, 3 mg/kg). The experiment consisted of four groups: control group, BLM group, and STE treatment groups (STE 50 and 100 mg/kg). ELISA and biochemical tests were conducted to determine the levels of TNF-α, IL-1β, IL-6, NO, hydroxyproline (HYP), SOD, GSH, and MDA. Histopathological changes and collagen deposition in lung tissues were observed by HE and Masson staining. Immunohistochemistry was performed to determine the levels of collagen I-, collagen III-, TGF-β1- and p-Smad2/3-positive cells. Western blot analysis was used to measure the expression of epithelial-mesenchymal transition (EMT) markers, including α-SMA, vimentin, E-cadherin, and ZO-1, as well as proteins related to the nuclear factor erythroid 2-related factor 2 (Nrf2) pathway, nuclear transcription factor-κB (NF-κB) pathway, and TGF-β1/Smad2/3 pathway in lung tissues. Results: STE significantly alleviated BLM-induced body weight loss and lung injury in mice, decreased HYP levels, and reduced the levels of collagen I- and collagen III-positive cells, thereby decreasing extracellular matrix (ECM) deposition. Moreover, STE markedly improved oxidative stress (MDA levels were decreased, while SOD and GSH activity were enhanced), the inflammatory response (the levels of TNF-α, IL-1β, IL-6, and NO were reduced), and EMT (the expression of α-SMA and vimentin was downregulated, and the expression of E-cadherin and ZO-1 was upregulated). Further mechanistic analysis revealed that STE could activate the Nrf2 pathway and inhibit the NF-κB and TGF-β1/Smad2/3 pathways. Conclusion: STE may alleviate oxidative stress by activating the Nrf2 pathway, suppress the inflammatory response by downregulating the NF-κB pathway, and inhibit EMT progression by blocking the TGF-β1/Smad2/3 pathway, thereby improving BLM-induced PF.

The development of a nucleus pulposus-derived cartilage analog scaffold for chondral repair and regeneration.

Focal chondral defects (FCDs) significantly impede quality of life for patients and impose severe economic costs on society. One of the most promising treatment options-autologous matrix-induced chondrogenesis (AMIC)-could benefit from a scaffold that contains both of the primary cartilage matrix components-sulfated glycosaminoglycans (sGAGs) and collagen type II. Here, 17 different protocols were evaluated to determine the most optimum strategy for decellularizing (decelling) the bovine nucleus pulposus (bNP) to yield a natural biomaterial with a cartilaginous constituency. The resulting scaffold was then characterized with respect to its biochemistry, biomechanics and cytocompatibility. Results indicated that the optimal decell protocol involved pre-crosslinking the tissue prior to undergoing decell with trypsin and Triton X-100. The residual DNA content of the scaffold was found to be 32.64 ± 9.26 ng/mg dry wt. of tissue with sGAG and hydroxyproline (HYP) contents of 72.53 ± 16.43. and 78.38 ± 8.46 μg/mg dry wt. respectively. The dynamic viscoelastic properties were found to be preserved (complex modulus: 17.92-16.62 kPa across a range of frequencies) while the equilibrium properties were found to have significantly decreased (aggregate modulus: 11.51 ± 9.19 kPa) compared to the non-decelled fresh bNP tissue. Furthermore, the construct was also found to be cytocompatible with bone marrow stem cells (BMSCs). While it was not permissive of cellular infiltration, the BMSCs were still found to have lined the laser drilled channels in the scaffold. Taken together, the biomaterial developed herein could be a valuable addition to the AMIC family of scaffolds or serve as an off-the-shelf standalone option for cartilage repair.

Deletion of prolyl hydroxylase domain-containing enzyme 3 (phd3) in zebrafish facilitates hypoxia tolerance

Prolyl hydroxylase domain (PHD)-containing enzyme 3 (PHD3) belongs to the Caenorhabditis elegans gene egl-9 family of prolyl hydroxylases. PHD3 catalyzes proline hydroxylation of hypoxia-inducible factor α (HIF-α) and promotes HIF-α proteasomal degradation through coordination with the pVHL complex under normoxic conditions. However, the relationship between PHD3 and the hypoxic response is not well understood. In this study, we used quantitative real-time PCR assay and O-dianisidine staining to characterize the hypoxic response in zebrafish deficient in phd3. We found that the hypoxia-responsive genes are upregulated and the number of erythrocytes was increased in phd3-null zebrafish compared with their wildtype siblings. On the other hand, we show overexpression of phd3 suppresses HIF-transcriptional activation. In addition, we demonstrate phd3 promotes polyubiquitination of zebrafish hif-1/2α proteins, leading to their proteasomal degradation. Finally, we found that compared with wildtype zebrafish, phd3-null zebrafish are more resistant to hypoxia treatment. Therefore, we conclude phd3 has a role in hypoxia tolerance. These results highlight the importance of modulation of the hypoxia signaling pathway by phd3 in hypoxia adaptation.

In situ profiling reveals metabolic alterations in the tumor microenvironment of ovarian cancer after chemotherapy

In this study, we investigated the metabolic alterations associated with clinical response to chemotherapy in patients with ovarian cancer. Pre- and post-neoadjuvant chemotherapy (NACT) tissues from patients with high-grade serous ovarian cancer (HGSC) who had poor response (PR) or excellent response (ER) to NACT were examined. Desorption electrospray ionization mass spectrometry (DESI-MS) was performed on sections of HGSC tissues collected according to a rigorous laparoscopic triage algorithm. Quantitative MS-based proteomics and phosphoproteomics were performed on a subgroup of pre-NACT samples. Highly abundant metabolites in the pre-NACT PR tumors were related to pyrimidine metabolism in the epithelial regions and oxygen-dependent proline hydroxylation of hypoxia-inducible factor alpha in the stromal regions. Metabolites more abundant in the epithelial regions of post-NACT PR tumors were involved in the metabolism of nucleotides, and metabolites more abundant in the stromal regions of post-NACT PR tumors were related to aspartate and asparagine metabolism, phenylalanine and tyrosine metabolism, nucleotide biosynthesis, and the urea cycle. A predictive model built on ions with differential abundances allowed the classification of patients’ tumor responses as ER or PR with 75% accuracy (10-fold cross-validation ridge regression model). These findings offer new insights related to differential responses to chemotherapy and could lead to novel actionable targets.

Peimine Alleviated Bleomycin-Induced Pulmonary Fibrosis in Mice Through Reducing Epithelial-Mesenchymal Transition, Inflammation and Oxidative Stress and Regulating Host Metabolism

Objectives Peimine (PM), derived from Fritillaria thunbergii Miq, has been demonstrated with protective effects on pulmonary fibrosis (PF). However, the detailed mechanisms of PM on PF remain unknown. The aim of current study was to assess the therapeutic effects and the possible mechanism of PM on PF. Methods In this study, mice received bleomycin (BLM) injection to induce PF and then received the treatment of PM orally. The therapeutic effects of PM on PF were firstly assessed through histopathological staining (hematoxylin and eosin and Masson staining) and measuring hydroxyproline (HYP) level in lung. Then, we measured the levels of epithelial-mesenchymal transition (EMT)-related markers (vimentin and E-cadherin), pro-inflammatory factors (interleukin [IL]-1β, IL-6, and tumor necrosis factor alpha [TNF-α]), and oxidative stress-related indicators (superoxide dismutase[SOD], malondialdehyde [MDA] and glutathione peroxidase [GSH-Px]) in lung. Furthermore, untargeted metabolomics were employed to explore the effects of PM on metabolites in lung. Results PM treatment improved the pathological changes including reducing the infiltration of inflammatory cells and decreasing collagen deposition, and decreasing the HYP level in lung in PF mice. Moreover, PM treatment up-regulated E-cadherin and down-regulated vimentin, decreased IL-1β, IL-6 and TNF-α expression, increased SOD and GSH-Px activities, and decreased MDA level in lung. Untargeted metabolomics analysis showed that PM altered the metabolites in lung of mice with BLM-induced PF. The differential metabolites were mainly associated with tryptophan metabolism, nicotinate and nicotinamide metabolism, alanine, aspartate and glutamate metabolism, arginine biosynthesis, and D-glutamine and D-glutamate metabolism. Conclusion PM exhibited therapeutic effects on BLM-induced PF mice including reducing collagen deposition, inhibiting EMT and reducing inflammation and oxidative stress. The mechanism of PM on PF may be associated with regulating tryptophan metabolism, nicotinate and nicotinamide metabolism, alanine, aspartate and glutamate metabolism, arginine biosynthesis, and D-glutamine and D-glutamate metabolism in lung.

The extract from Portulaca oleracea L. rehabilitates skin photoaging via adjusting miR-138-5p/Sirt1-mediated inflammation and oxidative stress

Photoaging is the main form of external skin aging, and ultraviolet radiation is the main cause. Long-term ultraviolet radiation can cause oxidative stress, inflammation, immune responses, and skin cell apoptosis. Therefore, it is necessary to explore active products from plants to treat skin photoaging. C57BL/6J mice were randomly divided into control, model, and purslane (Portulaca oleracea L.) extract-treated groups (150, 300, and 600 mg/kg). Ultraviolet (UV) radiation induces skin photoaging. Histopathological changes in the skin were observed by hematoxylin and eosin (H&E), Masson's trichrome, and toluidine staining. Levels of hydroxyproline (HYP), hyaluronic acid (HA), collagen I (COL1), catalase (CAT), malondialdehyde (MDA), and total superoxide dismutase (T-SOD) were measured. UVB-induced BJ and HaCaT cells were used to evaluate the effects of the crude extract. The effects of the purslane extract on miR-138-5p/Sirt1 signaling were then tested. The results showed that the purslane extract significantly increased cell viability in UVB-induced cells and decreased oxidative damage and inflammation. In addition, the extract affected the miR-138-5p levels in vivo and in vitro, and increased the levels of the target gene Sirt1. In UVB-induced cells, purslane extract significantly altered the expression levels of genes or proteins associated with miR-138-5p/Sirt1 signaling. Inflammation and oxidative damage were significantly enhanced when miR-138-5p was overexpressed, and the expression levels of the genes and proteins were reversed by the extract. Co-transfection with the miR-138-5p inhibitor and si-Sirt1 showed the same effects as the extract on the signal. Similar results have been observed in mice. In summary, purslane extract showed potent protective effects against skin photoaging by regulating the miR-138-5p/Sirt1 axis and should be used as a natural product for skin care.

Hepatocyte Growth Factor Delivered by Nanocomposites for Gene Therapy of Bleomycin-Induced Pulmonary Fibrosis in Rats.

Pulmonary fibrosis (PF) is a chronic and progressive interstitial lung disease. There is no effective treatment for PF. Hepatocyte growth factor (HGF) has anti-inflammatory and antifibrotic effects but has limited potential owing to its short half-life. To increase the transfection efficiency of pVAX-HGF, we prepared polyethyleneiminepolyethylene glycol: polyethyleneimine/pVAX-HGF (PEG-PEI: PEI/pVAX-HGF) nanocomposite loaded with a plasmid encoding the HGF gene. The PEG-PEI:PEI/pVAX-HGF characteristics, including morphology, particle size, zeta-potential, and DNA entrapment efficiency, were investigated. The pVAX-HGF nanocomposites with low toxicity and high transfection efficiency were screened by cell viability assay and cell transfection. The antifibrotic effect of pVAX-HGF nanocomposite on PF rats induced by bleomycin (BLM) was evaluated by pulmonary function measurement, pathological examination and collagen content assay. Different nanocomposites were prepared to deliver pVAX-HGF, in which mix1 (PEGPEI: PEI/pVAX-HGF) has lower potential and better entrapment ability. PEI/pVAX-HGF (N/P=25) nanocomposite with low toxicity and high transfection efficiency was administered to PF rats. After treatment with mix 1/pVAX-HGF, the index of lung function(including EF50, MV, TV, PEF and PIF) in mix 1/pVAX-HGF group was higher than that of the PF group. The number of cells in BALF of the mix 1/pVAX-HGF group was significantly lower than that of the PF groups, and the content of hydroxyproline(HYP) and collagen Type I (Col-I) in the lung of the mix 1/pVAX-HGF group was much lower than that of the PF groups in the early stage. The result of pathological examination showed that rats in the mix1/pVAX-HGF group showed obviously reduced alveolar septal thickening, fewer infiltrated inflammatory cells and less collagen deposition. The PEG-PEI:PEI/pVAX-HGF nanocomposite can ameliorate PF induced by BLM. The pVAX-HGF nanocomposite is a latent therapeutic strategy for PF.

In vitro and in vivo efficacy of naturally derived scaffolds for cartilage repair and regeneration.

Intrinsically present bioactive cues allow naturally derived materials to mimic important characteristics of cartilage while also facilitating cellular recruitment, infiltration, and differentiation. Such traits are often what tissue engineers desire when they fabricate scaffolds, and yet, literature from the past decade is replete with examples of how most natural constructs with native biomolecules have only offered sub-optimal results in the treatment of cartilage defects. This paper provides an in-depth investigation of the performance of such scaffolds through a review of a collection of natural materials that have been used so far in repairing/regenerating articular cartilage. Although in vivo and clinical studies are the best indicators of scaffold efficacy, it was, however, observed that a large number of natural constructs had very promising scaffold characteristics to begin with, and would often show good in vitro/in vivo results. Finally, an examination of the biochemistry and biomechanics of repair tissues in studies that reported positive outcomes showed that these attributes often approached target cartilage values. The paper concludes with an outline of current trends as well as future directions for the field. STATEMENT OF SIGNIFICANCE: This review offers an exclusive focus on natural scaffold materials for cartilage repair and regeneration and provides a quantitative and qualitative analysis of their performance under a variety of in vitro and in vivo conditions. Readers can learn about environments where natural scaffolds have had the most success and tailor strategies to optimize their own work. Furthermore, given how the glycosaminoglycan (GAG) to hydroxyproline (HYP) ratio and moduli are fundamental attributes of hyaline cartilage, this paper adds to the body of knowledge by exploring how these characteristics reflect in preclinical outcomes. Such perspectives can greatly aid researchers better utilize natural materials for Cartilage Tissue Engineering (CTE).

Oxygen-regulated post-translation modifications as master signalling pathway in cells.

Oxygen is essential for viability in mammalian organisms. However, cells are often exposed to changes in oxygen availability, due to either increased demand or reduced oxygen supply, herein called hypoxia. To be able to survive and/or adapt to hypoxia, cells activate a variety of signalling cascades resulting in changes to chromatin, gene expression, metabolism and viability. Cellular signalling is often mediated via post-translational modifications (PTMs), and this is no different in response to hypoxia. Many enzymes require oxygen for their activity and oxygen can directly influence several PTMS. Here, we review the direct impact of changes in oxygen availability on PTMs such as proline, asparagine, histidine and lysine hydroxylation, lysine and arginine methylation and cysteine dioxygenation, with a focus on mammalian systems. In addition, indirect hypoxia-dependent effects on phosphorylation, ubiquitination and sumoylation will also be discussed. Direct and indirect oxygen-regulated changes to PTMs are coordinated to achieve the cell's ultimate response to hypoxia. However, specific oxygen sensitivity and the functional relevance of some of the identified PTMs still require significant research.

A Screening Models of (In Vivo And In Vitro) Used for the Study of Hepatoprotective Agents

In order to evaluate hepatoprotective function, both in vitro and in vivo liver or hepatoprotective models have been constructed in the past. These methods examine a drug's potential to prevent or minimize liver damage in test animals. To express their effectiveness and safety in humans, new drugs must first travel through a number of developmental phases, beginning with the identification of their pharmacological characteristics in cellular and animal models. In the medical literature, there are many methods for measuring hepatoprotective efficacy in vivo and in vitro. Fresh hepatocytes are exposed to hepatotoxin treatment in in vitro models, and the effects of the test chemical on those cells are examined. To elicit liver damage in test animals, dangerous dosages of an identified hepatotoxin are administered in in vivo models. The test material is provided before, after, and simultaneously with the toxin treatment. Hepatitis in Long Evans and other chemical agents are commonly exploited to generate hepatotoxicity in experimental animals for the evaluation of hepatoprotective medications. Cinnamon rats, liver cirrhosis and necrosis, hepatic fibrosis brought on by carbon tetrachloride in rats, liver cirrhosis brought on by galactosamine, inhibition of proline hydroxylation, trans-heptic investigations model in dogs, etc. The many forms of in vivo and in vitro hepatoprotective screening models are explained in this article.

Mechanism of Wuling Capsules against hepatic fibrosis based on network pharmacology and animal experiments

The present study aimed to explore the underlying mechanism of Wuling Capsules in the treatment of hepatic fibrosis(HF) through network pharmacology, molecular docking, and animal experiments. Firstly, the chemical components and targets of Wuling Capsules against HF were searched from Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform(TCMSP), Traditional Chinese Medicines Integrated Database(TCMID), GeneCards, and literature retrieval. The protein-protein interaction(PPI) network analysis was carried out on the common targets by STRING database and Cytoscape 3.9.1 software, and the core targets were screened, followed by Gene Ontology(GO) and Kyoto Encyclopedia of Genes and Genomes(KEGG) pathway enrichment analyses. Enrichment analysis was conducted on the core targets and the &quot;drug-core component-target-pathway-disease&quot; network was further constructed. Subsequently, molecular docking between core components and core targets was conducted using AutoDock Vina software to predict the underlying mechanism of action against HF. Finally, an HF model induced by CCl_4 was constructed in rats, and the general signs and liver tissue morphology were observed. HE and Masson staining were used to analyze the liver tissue sections. The effects of Wuling Capsules on the levels of inflammatory factors, hydroxyproline(HYP) levels, and core targets were analyzed by ELISA, RT-PCR, etc. A total of 445 chemical components of Wuling Capsules were screened, corresponding to 3 882 potential targets, intersecting with 1 240 targets of HF, and 47 core targets such as TNF, IL6, INS, and PIK3CA were screened. GO and KEGG enrichment analysis showed that the core targets mainly affected the process of cell stimulation response and metabolic regulation, involving cancer, PI3K-Akt, MAPK, and other signaling pathways. Molecular docking showed that the core components of Wuling Capsules, such as lucidenic acid K, ganoderic acid B, lucidenic acid N, saikosaponin Q2, and neocryptotanshinone, had high affinities with the core targets, such as TNF, IL6 and PIK3CA. Animal experiments showed that Wuling Capsules could reduce fat vacuole, inflammatory infiltration, and collagen deposition in rat liver, decrease the levels of inflammatory cytokines TNF-α, IL-6, and HYP, and downregulated the expressions of PI3K and Akt mRNA. This study suggests that the anti-HF effect of Wuling Capsules may be achieved by regulating the PI3K-Akt signaling pathway, reducing the levels of TNF-α and IL-6 inflammatory factors, and inhibiting the excessive deposition of collagen.

Aqueous extract of Epimedium sagittatum mitigates pulmonary fibrosis in mice

This study aims to investigate the intervention effect of the aqueous extract of Epimedium sagittatum Maxim on the mouse model of bleomycin(BLM)-induced pulmonary fibrosis, so as to provide data support for the clinical treatment of pulmonary fibrosis. Ninety male C57BL/6N mice were randomized into normal(n=10), model(BLM, n=20), pirfenidone(PFD, 270 mg·kg~(-1), n=15), and low-, medium-, and high-dose E. sagittatum extract(1.67 g·kg~(-1), n=15; 3.33 g·kg~(-1), n=15; 6.67 g·kg~(-1), n=15) groups. The model of pulmonary fibrosis was established by intratracheal instillation of BLM(5 mg·kg~(-1)) in the other five groups except the normal group, which was treated with an equal amount of normal saline. On the day following the modeling, each group was treated with the corresponding drug by gavage for 21 days. During this period, the survival rate of the mice was counted. After gavage, the lung index was calculated, and the morphology and collagen deposition of the lung tissue were observed by hematoxylin-eosin(HE) and Masson staining, respectively. The levels of reactive oxygen species(ROS) in lung cell suspensions were measured by flow cytometry. The levels of glutathione peroxidase(GSH-Px), total superoxide dismutase(T-SOD), and malondialdehyde(MDA) the in lung tissue were measured. Terminal-deoxynucleoitidyl transferase-mediated nick-end labeling(TUNEL) was employed to examine the apoptosis of lung tissue cells. The content of interleukin-6(IL-6), chemokine C-C motif ligand 2(CCL-2), matrix metalloproteinase-8(MMP-8), transforming growth factor-beta 1(TGF-β1), alpha-smooth muscle actin(α-SMA), E-cadherin, collagen Ⅰ, and fibronectin in the lung tissue was measured by enzyme-linked immunosorbent assay(ELISA). The expression levels of F4/80, Ly-6G, TGF-β1, and collagen Ⅰ in the lung tissue were determined by immunohistochemistry. The mRNA levels of CCL-2, IL-6, and MMP-7 in the lung tissue were determined by qRT-PCR. The content of hydroxyproline(HYP) in the lung tissue was determined by alkaline hydrolysation. The expression of α-SMA and E-cadherin was detected by immunofluorescence, and the protein levels of α-SMA, vimentin, E-cadherin in the lung tissue were determined by Western blot. The results showed the aqueous extract of E. sagittatum increased the survival rate, decreased the lung index, alleviated the pathological injury, collagen deposition, and oxidative stress in the lung tissue, and reduced the apoptotic cells. Furthermore, the aqueous extract of E. sagittatum down-regulated the protein levels of F4/80 and Ly-6G and the mRNA levels of CCL-2, IL-6, and MMP-7 in the lung tissue, reduced the content of IL-6, CCL-2, and MMP-8 in the alveolar lavage fluid. In addition, it lowered the levels of HYP, TGF-β1, α-SMA, collagen Ⅰ, fibronectin, and vimentin, and elevated the levels of E-cadherin in the lung tissue. The aqueous extract of E. sagittatum can inhibit collagen deposition, alleviate oxidative stress, and reduce inflammatory response by regulating the expression of the molecules associated with epithelial-mesenchymal transition, thus alleviating the symptoms of bleomycin-induced pulmonary fibrosis in mice.

Alleviation of ultraviolet-B radiation-induced photoaging using Saussurea medusa Maxim polysaccharide.

Saussurea medusa polysaccharide, the polysaccharide extract of Saussurea medusa Maxim, a traditional Chinese herbal medicine, is used to combat intense ultraviolet radiation, cold, and hypoxia in patients, as well as during drought. This polysaccharide has rich medicinal and ecological values. We aimed to determine whether saussurea medusa polysaccharides can reduce ultraviolet B (UVB)-induced skin photoaging. Seventy-five male Kunming mice were divided into five groups: control, UVB-only, UVB plus vitamin E (VE group), UVB plus saussurea medusa (2 g/kg), and UVB plus saussurea medusa (6 g/kg). The control group was irradiated with normal light, while the other four groups were subcutaneously administered 10 mL/kg/day D-galactose and irradiated with narrow-spectrum UVB for 40 min daily. From day 11, the VE group was administered 0.25 g/kg/day vitamin E, while the saussurea medusa intervention groups were administered 2 and 6 g/kg/day saussurea medusa polysaccharide. After 30 days of continuous administration, treatment with saussurea medusa polysaccharides was found to reduce UVB-induced skin photoaging in mice by elevating the levels of superoxide dismutase, glutathione peroxidase, and hydroxyproline (HYP), while reducing the level of MDA, and inhibiting the EGFR/MEK/ERK/c-Fos pathway. Overall, our findings suggest that treatment with saussurea medusa polysaccharides positively influences skin photoaging.

Changes in markers of collagen metabolism in the blood serum of white rats during the filling of femur defects with implants based on polylactide and tricalcium phosphate with allogeneous mesenchymal stem cells

The use of synthetic materials in combination with osteogenesis stimulators is one of the advanced directions of the development of traumatology. The purpose of the study: based on the analysis of biochemical markers of collagen metabolism in the blood serum of laboratory rats with a femur defect, to evaluate the course of bone remodeling after filling the defect with implants based on polylactide and tricalcium phosphate with simultaneous and delayed administration of allogeneic mesenchymal stem cells (MSCs). On the model of a defect in the metaphysis of the femur in white rats, the indicators of collagen exchange in blood serum were studied: the content of protein-bound, free fractions, the amount of hydroxyproline (HOP), the ratio of the content of protein-bound HOP to free PB/F was calculated. Comparison of the results of different groups was performed using the Student-Fisher method. The difference was considered statistically significant if p&lt;0.05. Filling the defect with implants led to a decrease in the content of protein-bound HOP by 16.69 % and 14.34 % on the 15th and 90th days (p&lt;0.05), an increase in the content of free HOP by 74.96 %; 67.31 % and 56.74 % (p&lt;0.001), the content of the amount of HOP by 25.37 %; 23.66 % and 18.28 % (p&lt;0.05), and reduction of PB/F by 52.20 %; 49.90 % and 45.30 % (p&lt;0.001) relative to intact on the 15th; 30th and 90th days. Addition of MSCs to the implants at the same time as the installation caused a decrease in the content of free HOP by 63.90 %; 54.63 % and 42.76 % on the 15th; on the 30th and 90th days (p&lt;0.001), the total metabolite by 21.87 % and 18.58 % on the 15th and 30th days (p&lt;0.05) and a decrease in PB/F by 47, 50 %; 43.20 %; 37.60 % on the 15th; on the 30th and 90th days (p&lt;0.001) relative to the intact. Postponing the introduction of MSCs increased the content of free HOP by 40.48 % (p&lt;0.001); 20.49 % and 16.58 % (p&lt;0.05) with a lower PB/F by 38.20 %; 25.80 % and 23.40 % (p&lt;0.05) on the 15th; 30th and 90th days relatively intact. When the defect was filled with implants without MSCs, a moderate inhibition of anabolism and rapid activation of collagen destruction was observed. With the simultaneous use of implants and MSCs, the rate of formation and intense destruction of collagen was observed. When the introduction of MSCs was delayed, a moderate rate of destruction was recorded, which most contributed to collagen metabolism.

Influence of Phosphoric, Glycolic, and Ferulic Acids on Dentin Enzymatic Degradation, Ultimate Tensile Strength, and Permeability.

This study evaluated dentin enzymatic degradation based on the total matrix metalloproteinase (MMP) activity of demineralized dentin matrices before and after exposure to phosphoric acid (PA), glycolic acid (GA), and ferulic acid (FA). The release of hydroxyproline (HP), ultimate tensile strength (UTS), and dentin permeability (DP) were also evaluated. Dentin collagen matrices were assessed according to total MMP activity before and after treatment with the tested acids (n=10) for 15 seconds and compared with the control (GM6001 inhibitor). Dentin beams were analyzed for HP release and UTS after the treatments. Dentin discs were tested for DP at a pressure of 5 psi before and after treatment with the acids (n=10). The FA group had a lower percentage of enzymatic inhibition than the PA and GA groups (p<0.0001). No significant difference in UTS was found among the acids (p=0.6824), but HP release was significantly higher in the FA group than in the PA and GA groups (p<0.0001). No significant difference in DP was found for the acids (p=0.0535). GA led to less activation of MMPs and less release of HP, whereas the UTS and DP for GA were like those found for PA. In contrast, FA promoted greater enzymatic activity and greater release of HP, while having similar results to GA and PA regarding mechanical properties.