Mechanical stress abnormalities promote chondrocyte senescence - The pathogenesis of knee osteoarthritis.

Knee osteoarthritis (KOA) is a common chronic disease in orthopedics, which brings great pain to patients' life and spirit. Therefore, it is necessary to elucidate the pathogenesis of KOA. The pathophysiology of KOA has been linked to numerous factors, including oxidative stress, apoptosis, cellular senescence, mitochondrial dysfunction, and inflammatory factors. Cellular senescence has grown in importance as a topic of study for age-related illnesses recently. KOA has also been discovered to be closely related to human aging, a process in which chondrocyte senescence may be crucial. Numerous researches have looked at the pathogenesis of KOA from the perspectives of mechanical stress abnormalities, oxidative stress, inflammatory overexpression, and mitochondrial dysfunction. Many studies have discovered that the primary pathogenesis of KOA is inflammatory overexpression and chondrocyte death brought on by an imbalance in the joint microenvironment. And abnormal mechanical stress is the initiating cause of oxidative stress, inflammation, and mitochondrial disorders. However, few findings have been reported in the literature on the relationship between these factors, especially for mechanical stress abnormalities, and chondrocyte senescence. This time, in order to better understand the pathogenesis of KOA and identify potential connections between chondrocyte senescence and these microenvironments in KOA, as well as oxidative stress, inflammatory overexpression, and mitochondrial dysfunction microenvironmental dysfunctions, we will use chondrocyte senescence as a starting point. This will allow us to develop new therapeutic approaches for KOA.

Mesenchymal Stem Cells Ameliorate Fibrosis by Enhancing Autophagy via Inhibiting Galectin-3/Akt/mTOR Pathway and by Alleviating the EMT via Inhibiting Galectin-3/Akt/GSK3ß/Snail Pathway in NRK-52E Fibrosis.

Background and Objectives: Epithelial-Mesenchymal transition (EMT) is one of the origins of myofibroblasts in renal interstitial fibrosis. Mesenchymal stem cells (MSCs) alleviating EMT has been proved, but the concrete mechanism is unclear. To explore the mechanism, serum-free MSCs conditioned medium (SF-MSCs-CM) was used to treat rat renal tubular epithelial cells (NRK-52E) fibrosis induced by transforming growth factor-ß1 (TGF-ß1) which ameliorated EMT. Methods and Results: Galectin-3 knockdown (Gal-3 KD) and overexpression (Gal-3 OE) lentiviral vectors were established and transfected into NRK-52E. NRK-52E fibrosis model was induced by TGF-ß1 and treated with the SF-MSCs-CM for 24 h after modelling. Fibrosis and autophagy related indexes were detected by western blot and immunocytochemistry. In model group, the expressions of α-smooth muscle actin (α-SMA), fibronectin (FN), Galectin-3, Snail, Kim-1, and the ratios of P-Akt/Akt, P-GSK3ß/GSK3ß, P-PI3K/PI3K, P-mTOR/mTOR, TIMP1/MMP9, and LC3B-II/I were obviously increased, and E-Cadherin (E-cad) and P62 decreased significantly compared with control group. SF-MSCs-CM showed an opposite trend after treatment compared with model group. Whether in Gal-3 KD or Gal-3 OE NRK-52E cells, SF-MSCs-CM also showed similar trends. However, the effects of anti-fibrosis and enhanced autophagy in Gal-3 KD cells were more obvious than those in Gal-3 OE cells. Conclusions: SF-MSCs-CM probably alleviated the EMT via inhibiting Galectin-3/Akt/GSK3ß/Snail pathway. Meanwhile, Gal-3 KD possibly enhanced autophagy via inhibiting Galectin-3/Akt/mTOR pathway, which synergistically ameliorated renal fibrosis. Targeting galectin-3 may be a potential target for the treatment of renal fibrosis.

Elucidating the mechanism of Hongjinshen decoction in the treatment of pulmonary fibrosis based on network pharmacology and molecular docking.

BACKGROUND: To explore the mechanism of compound Hongginshen decoction in improving pulmonary fibrosis based on network pharmacology. METHODS: The active components and targets of ginseng and Salvia miltiorrhiza were screened from the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP) database. The chemical components of Rhodiola, Ophiopogon japonicus, and Dendrobium were screened using the Traditional Chinese Medicine Integrated Database (TCMID), and the target compounds were predicted by the Swisstargets method. The related target genes of pulmonary fiber (PF) were screened by the Genecards database and the National Center of Biotechnology Information (NCBI) database. The protein-protein interaction network was drawn using the string database and Cytoscape software, and the network topology was analyzed. Then, using R3.6.3 software, biological processes, molecular function, cell component enrichment, and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment were carried out on the common targets of drugs and diseases. The network diagram of the "traditional Chinese medicine composition disease target" of Compound Hongginshen Decoction was constructed and analyzed with the software of Cytoscape 3.6.1. RESULTS: We identified 159 active components and 2820 targets in Compound Hongginshen Decoction, and 2680 targets in pulmonary fibrosis. A total of 343 common targets were obtained by the intersection of drug targets and disease targets. protein-protein interaction protein interaction network analysis showed that PIK3CA, PIK3R1, MAPK1, SRC, AKT1, and so on may be the core targets of the compound Hongjingshen recipe in the treatment of pulmonary fibrosis. Gene Ontology (GO) enrichment analysis identified 3463 items, and KEGG pathway enrichment analysis identified 181 related signaling pathways, including the PI3K-Akt signaling pathway, HCMV pathway, Hb pathway, PGs pathway, and KSHV signaling pathway. CONCLUSION: Compound Hongginshen Decoction has the characteristics of a multichannel and multitargeted effect in the treatment of pulmonary fibrosis. Radix Ophiopogonis and Dendrobium officinale play a key role in the treatment of pulmonary fibrosis. The whole compound prescription may play a therapeutic role by affecting cell metabolism, being anti-inflammatory, regulating the immune system, promoting angiogenesis, and improving anaerobic metabolism.

Mesenchymal stem cells ameliorate renal fibrosis by galectin-3/Akt/GSK3ß/Snail signaling pathway in adenine-induced nephropathy rat.

BACKGROUND: Tubulointerstitial fibrosis (TIF) is one of the main pathological features of various progressive renal damages and chronic kidney diseases. Mesenchymal stromal cells (MSCs) have been verified with significant improvement in the therapy of fibrosis diseases, but the mechanism is still unclear. We attempted to explore the new mechanism and therapeutic target of MSCs against renal fibrosis based on renal proteomics. METHODS: TIF model was induced by adenine gavage. Bone marrow-derived MSCs was injected by tail vein after modeling. Renal function and fibrosis related parameters were assessed by Masson, Sirius red, immunohistochemistry, and western blot. Renal proteomics was analyzed using iTRAQ-based mass spectrometry. Further possible mechanism was explored by transfected galectin-3 gene for knockdown (Gal-3 KD) and overexpression (Gal-3 OE) in HK-2 cells with lentiviral vector. RESULTS: MSCs treatment clearly decreased the expression of α-SMA, collagen type I, II, III, TGF-ß1, Kim-1, p-Smad2/3, IL-6, IL-1ß, and TNFα compared with model rats, while p38 MAPK increased. Proteomics showed that only 40 proteins exhibited significant differences (30 upregulated, 10 downregulated) compared MSCs group with the model group. Galectin-3 was downregulated significantly in renal tissues and TGF-ß1-induced rat tubular epithelial cells and interstitial fibroblasts, consistent with the iTRAQ results. Gal-3 KD notably inhibited the expression of p-Akt, p-GSK3ß and snail in TGF-ß1-induced HK-2 cells fibrosis. On the contrary, Gal-3 OE obviously increased the expression of p-Akt, p-GSK3ß and snail. CONCLUSION: The mechanism of MSCs anti-renal fibrosis was probably mediated by galectin-3/Akt/GSK3ß/Snail signaling pathway. Galectin-3 may be a valuable target for treating renal fibrosis.