The incidence of acute kidney injury (AKI) due to ischemia-reperfusion (IR) injury is increasing. There is no effective treatment for AKI, and because of this clinical challenge, AKI often progresses ...to chronic kidney disease, which is closely associated with poor patient outcomes and high mortality rates. Small extracellular vesicles from human umbilical cord mesenchymal stem cells (hUCMSC-sEVs) play increasingly vital roles in protecting tissue function from the effects of various harmful stimuli owing to their specific biological features. In this study, we found that miR-100-5p was enriched in hUCMSC-sEVs, and miR-100-5p targeted FKBP5 and inhibited HK-2 cell apoptosis by activating the AKT pathway. HK-2 cells that were exposed to IR injury were cocultured with hUCMSC-sEVs, leading to an increase in miR-100-5p levels, a decrease in FKBP5 levels, and an increase in AKT phosphorylation at Ser 473 (AKT-473 phosphorylation). Notably, these effects were significantly reversed by transfecting hUCMSCs with an miR-100-5p inhibitor. Moreover, miR-100-5p targeted FKBP5, as confirmed by a dual luciferase reporter assay. In vivo, intravenous infusion of hUCMSC-sEVs into mice suffering from IR injury resulted in significant apoptosis inhibition, functional maintenance and renal histological protection, which in turn decreased FKBP5 expression levels. Overall, this study revealed an effect of hUCMSC-sEVs on inhibiting apoptosis; hUCMSC-sEVs reduced renal IR injury by delivering miR-100-5p to HK-2 cells, targeting FKBP5 and thereby promoting AKT-473 phosphorylation to activate the AKT pathway. This study provides novel insights into the role of hUCMSC-sEVs in the treatment of AKI.
Seventeen α-aminophosphonates are synthesized. Their compositions and structures are established by EA, UV, FT-IR, 1H NMR, 13C NMR, 31P NMR and ESI-MS. Compounds 1–4 are confirmed by X-ray ...crystallography. PTP inhibition shows compounds 1–5, 12, 15 are moderate competitive inhibitors with some selectivity. The most potent inhibitor is compound 5 with the lowest IC50 value about 6.64 μM against PTP1B, about 2-fold and 25-fold stronger than against TCPTP and PTP-MEG2 while it doesn't inhibit SHP-1 and SHP-2. The binding constant of 5 to PTP1B is 2.23 × 105 M−1 and binding ratio approximates 1:1. Cell viability and apoptosis assays indicate 5 is cell permeable with lower cytotoxicity. The results indicate α-aminophosphonates are possibly developed to effective and selective inhibitors of PTPs.
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► New α-aminophosphonates are synthesized and characterized. ► PTP inhibition assays show 5 potently and selectively inhibits PTP1B and TCPTP. ► Compound 5 is cell permeable with lower cytotoxicity.
Single-crystalline EuF3 hexagonal microdisks with hollow interior were fabricated to serve as a background-free matrix for analysis of small molecules and polyethylene glycols (PEGs) by ...matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS). The long-lived excited state of europium ions can transfer energy to high-energy vibrations of organic molecules, which provides the potential technological application in MALDI-TOF-MS analysis of small molecules and PEGs. The efficiency of the hollow microdisks as a novel matrix of low molecular weight compounds was verified by analysis of small peptide, amino acid, organic compounds, and hydroxypropyl β-cyclodextrin (HP-β-CD). The advantage of this matrix in comparison with α-cyano-4-hydroxycinnamic acid (CHCA) and 2,5-dihydroxybenzoic acid (DHB) was demonstrated by MALDI-TOF-MS analysis of an amino acid mixture and a peptide mixture. This matrix is successfully used for analysis of PEGs (PEG 2000, PEG 4000, PEG 8000, PEG 15000, and PEG 30000), suggesting a potential for monitoring reactions and for synthetic polymer quality control. The upper limit of detectable mass range was ∼35 000 Da (PEG 30000). It is believed that this work will not only offer a new technique for high-speed analysis of small molecules and PEGs but also open a new field for applications of rare earth fluorides.
Ferroptosis is a predominant contributor to graft kidney ischemia‒reperfusion injury (IRI), resulting in delayed graft function (DGF). However, much less is known about the early predicting ...biomarkers and therapeutic targets of DGF, especially aiming at ferroptosis. Here, we propose a precise predicting model for DGF, relying on the Akirin1 level in extracellular vesicles (EVs) derived from recipient urine 48 h after kidney transplant. In addition, we decipher a new molecular mechanism whereby Akirin1 induces ferroptosis by strengthening TP53‐mediated suppression of SLC7A11 during the graft kidney IRI process, that is, Akirin1 activates the EGR1/TP53 axis and inhibits MDM2‐mediated TP53 ubiquitination, accordingly upregulating TP53 in two ways. Meanwhile, we present the first evidence that miR‐136‐5p enriched in EVs secreted by human umbilical cord mesenchymal stem cells (UM‐EVs) confers robust protection against ferroptosis and graft kidney IRI by targeted inhibition of Akirin1 but knockout of miR‐136‐5p in UM sharply mitigates the protection of UM‐EVs. The functional and mechanistic regulation of Akirin1 is further corroborated in an allograft kidney transplant model in wild‐type and Akirin1‐knockout mice. In summary, these findings suggest that Akirin1, which prominently induces ferroptosis, is a pivotal biomarker and target for early diagnosis and treatment of graft kidney IRI and DGF after kidney transplant.
Proposed model for how UM‐EVs mitigate ferroptosis and protect against graft kidney IRI. Akirin1, which is prominently elevated in the kidney IRI process, promotes EGR1‐mediated TP53 expression and suppresses MDM2‐mediated TP53 ubiquitination and degradation, accordingly upregulating TP53 in two ways. This further enhances TP53‐mediated suppression of SLC7A11 and thus facilitates ferroptosis. MiR‐136‐5p enriched in UM‐EVs protects against ferroptosis and graft kidney IRI by inhibiting Akirin1.
A concise method to synthesize benzo
cphenanthridine alkaloid, nornitidine, was developed utilizing nickel- or palladium-catalyzed iminoannulation of an internal alkyne. The advantages of this ...strategy included readily available starting materials, inexpensive reagents, short reaction steps, and good yields.
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Bicalutamide (BIC) resistance impedes the treatment of prostate cancer (PCa) and seems to involve ferroptosis; however, the underlying mechanism remains unclear. Our study aimed to explore how ...miR-15b-3p modulates ferroptosis in response to BIC resistance and determine whether the miRNA is suitable for early screening of PCa. Here, we found that PCa tissues had significantly higher miR-15b-3p expression than adjacent normal tissues. Analysis of blood samples in patients who underwent prostate-specific antigen (PSA) screening revealed that miR-15b-3p was a more accurate diagnostic than PSA (miR-15b-3p area under the curve AUC = 0.941, PSA AUC = 0.815). In vitro experiments then demonstrated that miR-15b-3p expression was markedly higher in LNCaP, PC-3, and DU145 cells than in RWPE-1 cells. Treatment with BIC decreased miR-15b-3p expression and progressive ferroptosis. Mechanistically, we identified KLF2 as the downstream target of miR-15b-3p. Overexpressing KLF2 facilitated ferroptosis via augmenting MDA and iron concentrations, in turn inhibiting the SLC7A11/GPX4 axis and decreasing GSH concentration. Through modulating ferroptosis, miR-15b-3p mimic and inhibitor weakened and enhanced BIC sensitivity, respectively. Furthermore, BIC treatment limited xenograft tumor volume in vivo, whereas agomir-15b-3p promoted tumor growth, indicating that miR-15b-3p attenuated the tumor-suppressive effects of BIC. Taken together, our results suggested that miR-15b-3p is crucial to BIC resistance, specifically via targeting KLF2 and thereby suppressing ferroptosis. High miR-15b-3p expression in early PCa screening should reflect a higher probability of cancer. In conclusion, miR-15b-3p has strong potential as a screening and diagnostic biomarker with reliable prospects for clinical application. Furthermore, because patients with high miR-15b-3p and low KLF2 expression have a greater risk of BIC resistance and malignant progression, targeting the miRNA and its downstream protein may be a new treatment strategy.
A series of copper complexes with multi-benzimidazole derivatives, including mono- and di-nuclear, were synthesized and characterized by Fourier transform IR spectroscopy, UV–Vis spectroscopy, ...elemental analysis, electrospray ionization mass spectrometry. The speciation of Cu/NTB in aqueous solution was investigated by potentiometric pH titrations. Their inhibitory effects against human protein tyrosine phosphatase 1B (PTP1B), T-cell protein tyrosine phosphatase (TCPTP), megakaryocyte protein tyrosine phosphatase 2 (PTP-MEG2), srchomology phosphatase 1 (SHP-1) and srchomology phosphatase 2 (SHP-2) were evaluated in vitro. The five copper complexes exhibit potent inhibition against PTP1B, TCPTP and PTP-MEG2 with almost same inhibitory effects with IC
50
at submicro molar level and about tenfold weaker inhibition versus SHP-1, but almost no inhibition against SHP-2. Kinetic analysis indicates that they are reversible competitive inhibitors of PTP1B. Fluorescence study on the interaction between PTP1B and complex
2
or
4
suggests that the complexes bind to PTP1B with the formation of a 1:1 complex. The binding constant are about 1.14 × 10
6
and 1.87 × 10
6
M
−1
at 310 K for
2
and
4
, respectively.
An animal model of laminectomy in rats was used to study scar tissue formation around the spinal cord. Dexamethasone, in controlled-release form, was tested in this system for its ability to decrease ...fibrous tissue formation.
The results were evaluated to determine whether dexamethasone in a biodegradable controlled-release vehicle could be used to limit scar tissue formation around the spinal cord after laminectomy.
Steroids can delay the formation of scar tissue. Continued treatment with dexamethasone results in various unacceptable side effects. Use of biodegradable controlled-release vehicles to deliver drugs may allow for prolonged low-dose treatment, concentrated at the surgical site, thereby avoiding side effects.
Forty-four Sprague Dawley rats underwent laminectomies and were treated with dexamethasone in one of two controlled-release vehicles or with vehicle alone. After 4 weeks, the rats were killed and histologic sections prepared from the spines were examined and graded by a pathologist. In addition, the dexamethasone preparations were introduced into Hunt-Schilling wound chambers, which were implanted in rats. Four weeks after implantation, the wound chambers were removed and the tissue inside was assayed for DNA and protein content.
Dexamethasone acetate (Decadron, MSD, West Point, PA) significantly reduced the density of the scar tissue undermining the laminas. Steroids embedded in polymer did not change the scar formation in the back, but did decrease protein and DNA values in wound chamber tissues.
Long-term release of small amounts of steroid from the polymer poly-carboxy-phenoxypropane does not appear to reduce scar at laminectomy sites but does decrease the protein:DNA ratio in wound chambers. In contrast, Decadron does not significantly alter the biochemistry of wound chamber tissue but does reduce scar in the back.
This paper describes a practical synthetic approach to preparation of an immunosuppressant, FTY720. The key steps involve an iron-catalyzed cross-coupling reaction and a Wittig reaction. The ...advantages of this synthesis include readily available starting materials, inexpensive reagents, simple operations and good yields.
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