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Journal of Obstetrics and Gynaecology :... Dec 2023This study evaluated the radiosensitising effect of niraparib; a poly(adenosine diphosphate-ribose) polymerase (PARP) inhibitor on HeLa cervical cancer cells in nude...
This study evaluated the radiosensitising effect of niraparib; a poly(adenosine diphosphate-ribose) polymerase (PARP) inhibitor on HeLa cervical cancer cells in nude mice and explored its possible mechanism. Twenty-four 3-5-week-old female BALB/c nude mice, inoculated with HeLa cells into the right hind leg, were randomly assigned into eight groups with three mice per group and treated. The tumour volume was significantly reduced under niraparib + radiotherapy combination as compared to monotherapy and untreated mice. The tumour growth was significantly delayed by 23.33-39 days when treated with combination therapy (<.05). Further, univariate analysis revealed prolonged time for tumour growth when radiotherapy was followed by niraparib (I.G.) rather than niraparib (I.P.) (=.003). Combination therapy reduced levels of PARP-1 precursor, PARP-1 splicer, PAR and RAD51 protein with high expression of γ-H2AX/CC3 and low expression of Ki-67. Niraparib in combination with radiotherapy can enhance the formation of DNA double strand breaks in HeLa cells and up regulate the expression of γ-H2AX/CC3.IMPACT STATEMENT Asia has the highest incidence of cervical cancer (58.2%). Poly(adenosine diphosphate-ribose) polymerases (PARPs) are family of enzymes involved in single-strand break (SSB) and double-strand break (DSB) repair pathways. Niraparib is an effective inhibitor of both PARP-1 and PARP-2 and has the ability to cross the blood-brain barrier. Our study demonstrated that the combination of niraparib and radiotherapy can significantly enhance the cytotoxicity induced by radiotherapy. The inhibition effect of radiotherapy combined with niraparib on the tumour growth of mice was prominent, thereby establishing the radio-sensitisation activity of niraparib. Niraparib can improve the cytotoxic effect of radiotherapy by increasing the formation of DSBs and up regulating the expression of apoptotic protein in HeLa cells.
Topics: Humans; Female; Animals; Mice; Poly(ADP-ribose) Polymerase Inhibitors; Mice, Nude; Uterine Cervical Neoplasms; HeLa Cells; Heterografts; Ribose; Antineoplastic Agents; Adenosine Diphosphate; Cell Line, Tumor
PubMed: 36786286
DOI: 10.1080/01443615.2023.2171783 -
Redox Biology Oct 2023Enhancing energy turnover via uncoupled mitochondrial respiration in adipose tissue has great potential to improve human obesity and other metabolic complications....
OBJECTIVE
Enhancing energy turnover via uncoupled mitochondrial respiration in adipose tissue has great potential to improve human obesity and other metabolic complications. However, the amount of human brown adipose tissue and its uncoupling protein 1 (UCP1) is low in obese patients. Recently, a class of endogenous molecules, N-acyl amino acids (NAAs), was identified as mitochondrial uncouplers in murine adipocytes, presumably acting via the adenine nucleotide translocator (ANT). Given the translational potential, we investigated the bioenergetic effects of NAAs in human adipocytes, characterizing beneficial and adverse effects, dose ranges, amino acid derivatives and underlying mechanisms.
METHOD
NAAs with neutral (phenylalanine, leucine, isoleucine) and polar (lysine) residues were synthetized and assessed in intact and permeabilized human adipocytes using plate-based respirometry. The Seahorse technology was applied to measure bioenergetic parameters, dose-dependency, interference with UCP1 and adenine nucleotide translocase (ANT) activity, as well as differences to the established chemical uncouplers niclosamide ethanolamine (NEN) and 2,4-dinitrophenol (DNP).
RESULT
NAAs with neutral amino acid residues potently induce uncoupled respiration in human adipocytes in a dose-dependent manner, even in the presence of the UCP1-inhibitor guanosine diphosphate (GDP) and the ANT-inhibitor carboxyatractylate (CAT). However, neutral NAAs significantly reduce maximal oxidation rates, mitochondrial ATP-production, coupling efficiency and reduce adipocyte viability at concentrations above 25 μM. The in vitro therapeutic index (using induced proton leak and viability as determinants) of NAAs is lower than that of NEN and DNP.
CONCLUSION
NAAs are potent mitochondrial uncouplers in human adipocytes, independent of UCP1 and ANT. However, previously unnoticed adverse effects harm adipocyte functionality, reduce the therapeutic index of NAAs in vitro and therefore question their suitability as anti-obesity agents without further chemical modifications.
Topics: Humans; Animals; Mice; Amino Acids; Adipocytes; Ethanolamine; Adipose Tissue, Brown; Energy Metabolism
PubMed: 37683300
DOI: 10.1016/j.redox.2023.102874 -
Oncotarget Sep 2023UDP-glucose-6-dehydrogenase (UGDH) is a cytosolic, hexameric enzyme that converts UDP-glucose to UDP-glucuronic acid (UDP-GlcUA), a key reaction in hormone and... (Review)
Review
UDP-glucose-6-dehydrogenase (UGDH) is a cytosolic, hexameric enzyme that converts UDP-glucose to UDP-glucuronic acid (UDP-GlcUA), a key reaction in hormone and xenobiotic metabolism and in the production of extracellular matrix precursors. In this review, we classify UGDH as a molecular indicator of tumor progression in multiple cancer types, describe its involvement in key canonical cancer signaling pathways, and identify methods to inhibit UGDH, its substrates, and its downstream products. As such, we position UGDH as an enzyme to be exploited as a potential prognostication marker in oncology and a therapeutic target in cancer biology.
Topics: Humans; Uridine Diphosphate Glucose Dehydrogenase; Uridine Diphosphate Glucose; Neoplasms; Medical Oncology; Glucose; Biology; Glucose Dehydrogenases
PubMed: 37769033
DOI: 10.18632/oncotarget.28514 -
Nature Communications Nov 2023Methyl jasmonate (MeJA) is a known elicitor of plant specialized metabolism, including triterpenoid saponins. Saponaria vaccaria is an annual herb used in traditional...
Methyl jasmonate (MeJA) is a known elicitor of plant specialized metabolism, including triterpenoid saponins. Saponaria vaccaria is an annual herb used in traditional Chinese medicine, containing large quantities of oleanane-type triterpenoid saponins with anticancer properties and structural similarities to the vaccine adjuvant QS-21. Leveraging the MeJA-elicited saponin biosynthesis, we identify multiple enzymes catalyzing the oxidation and glycosylation of triterpenoids in S. vaccaria. This exploration is aided by Pacbio full-length transcriptome sequencing and gene expression analysis. A cellulose synthase-like enzyme can not only glucuronidate triterpenoid aglycones but also alter the product profile of a cytochrome P450 monooxygenase via preference for the aldehyde intermediate. Furthermore, the discovery of a UDP-glucose 4,6-dehydratase and a UDP-4-keto-6-deoxy-glucose reductase reveals the biosynthetic pathway for the rare nucleotide sugar UDP-D-fucose, a likely sugar donor for fucosylation of plant natural products. Our work enables the production and optimization of high-value saponins in microorganisms and plants through synthetic biology approaches.
Topics: Triterpenes; Transcriptome; Saponaria; Vaccaria; Plants; Saponins; Uridine Diphosphate; Glucose; Sugars
PubMed: 37925486
DOI: 10.1038/s41467-023-42877-0 -
Circulation Journal : Official Journal... Jul 2023Carpal tunnel syndrome (CTS) is considered an early sign of cardiac amyloidosis (CA) because amyloid deposition is often confirmed in the tenosynovium removed during...
BACKGROUND
Carpal tunnel syndrome (CTS) is considered an early sign of cardiac amyloidosis (CA) because amyloid deposition is often confirmed in the tenosynovium removed during carpal tunnel release (CTR); however, the prevalence of concomitant CA is unclear.Methods and Results: We prospectively examined 700 patients who underwent CTR and evaluated amyloid deposition after tenosynovium removal. Amyloid deposition was observed in 261 (37%) patients, who were significantly older and predominantly male (P<0.05). Of them, 120 agreed to cardiac screening. We performed Tc-labeled pyrophosphate (Tc-PYP) scintigraphy in 12 patients who met either of the following criteria: (1) interventricular septal diameter (IVSd) ≥14 mm or (2) 12 mm ≤ IVSd < 14 mm with above-normal limits in high-sensitivity cardiac troponin T (hs-cTnT). Six patients (50%) had positive findings on Tc-PYP scintigraphy and were diagnosed with wild-type transthyretin CA. Concomitant CA was observed in 6/120 (5%) CTR patients with amyloid deposition and 50% (6/12) in patients with left ventricular hypertrophy (≥12 mm) with increased hs-cTnT levels.
CONCLUSIONS
Amyloid deposition was frequently observed in the removed tenosynovium of elderly men with CTS. Cardiac screening may be useful for early diagnosis of CA in patients undergoing CTR with amyloid deposition.
Topics: Humans; Male; Aged; Female; Carpal Tunnel Syndrome; Technetium Tc 99m Pyrophosphate; Prevalence; Amyloidosis; Hypertrophy, Left Ventricular
PubMed: 37316262
DOI: 10.1253/circj.CJ-23-0223 -
Neurology India 2023
Topics: Humans; Cytidine Diphosphate Choline; Stroke; Brain Ischemia
PubMed: 37929465
DOI: 10.4103/0028-3886.388077 -
Cancer Metastasis Reviews Jun 2024We describe here the molecular basis of the complex formation of PRUNE1 with the tumor metastasis suppressors NME1 and NME2, two isoforms appertaining to the nucleoside... (Review)
Review
We describe here the molecular basis of the complex formation of PRUNE1 with the tumor metastasis suppressors NME1 and NME2, two isoforms appertaining to the nucleoside diphosphate kinase (NDPK) enzyme family, and how this complex regulates signaling the immune system and energy metabolism, thereby shaping the tumor microenvironment (TME). Disrupting the interaction between NME1/2 and PRUNE1, as suggested, holds the potential to be an excellent therapeutic target for the treatment of cancer and the inhibition of metastasis dissemination. Furthermore, we postulate an interaction and regulation of the other Class I NME proteins, NME3 and NME4 proteins, with PRUNE1 and discuss potential functions. Class I NME1-4 proteins are NTP/NDP transphosphorylases required for balancing the intracellular pools of nucleotide diphosphates and triphosphates. They regulate different cellular functions by interacting with a large variety of other proteins, and in cancer and metastasis processes, they can exert pro- and anti-oncogenic properties depending on the cellular context. In this review, we therefore additionally discuss general aspects of class1 NME and PRUNE1 molecular structures as well as their posttranslational modifications and subcellular localization. The current knowledge on the contributions of PRUNE1 as well as NME proteins to signaling cascades is summarized with a special regard to cancer and metastasis.
Topics: Humans; Energy Metabolism; Neoplasms; Signal Transduction; Neoplasm Metastasis; NM23 Nucleoside Diphosphate Kinases; Animals; Nucleoside-Diphosphate Kinase; Acid Anhydride Hydrolases; Tumor Microenvironment; Phosphoric Monoester Hydrolases
PubMed: 38180572
DOI: 10.1007/s10555-023-10165-4 -
BioRxiv : the Preprint Server For... Mar 2024Fusicoccadiene synthase from (PaFS) is a bifunctional assembly-line terpene synthase containing a prenyltransferase domain that generates geranylgeranyl diphosphate...
Fusicoccadiene synthase from (PaFS) is a bifunctional assembly-line terpene synthase containing a prenyltransferase domain that generates geranylgeranyl diphosphate (GGPP) from dimethylallyl diphosphate (DMAPP) and three equivalents of isopentenyl diphosphate (IPP), and a cyclase domain that converts GGPP into fusicoccadiene, a precursor of the diterpene glycoside Fusicoccin A. The two catalytic domains are linked by a flexible 69-residue polypeptide segment. The prenyltransferase domain mediates oligomerization to form predominantly octamers, and cyclase domains are randomly splayed out around the prenyltransferase core. Previous studies suggest that substrate channeling is operative in catalysis, since most of the GGPP formed by the prenyltransferase remains on the protein for the cyclization reaction. Here, we demonstrate that the flexible linker is not required for substrate channeling, nor must the prenyltransferase and cyclase domains be covalently linked to sustain substrate channeling. Moreover, substrate competition experiments with other diterpene cyclases indicate that the PaFS prenyltransferase and cyclase domains are preferential partners regardless of whether they are covalently linked or not. The cryo-EM structure of engineered "linkerless" construct PaFS, in which the 69-residue linker is spliced out and replaced with the tripeptide PTQ, reveals that cyclase pairs associate with all four sides of the prenyltransferase octamer. Taken together, these results suggest that optimal substrate channeling is achieved when a cyclase domain associates with the side of the prenyltransferase octamer, regardless of whether the two domains are covalently linked and regardless of whether this interaction is transient or locked in place.
PubMed: 38586022
DOI: 10.1101/2024.03.25.586617 -
Science Advances Nov 2023expresses glycerol phosphate wall teichoic acid (WTA), but some health care-associated methicillin-resistant (HA-MRSE) clones produce a second, ribitol phosphate...
expresses glycerol phosphate wall teichoic acid (WTA), but some health care-associated methicillin-resistant (HA-MRSE) clones produce a second, ribitol phosphate (RboP) WTA, resembling that of the aggressive pathogen . RboP-WTA promotes HA-MRSE persistence and virulence in bloodstream infections. We report here that the TarM enzyme of HA-MRSE [TarM(Se)] glycosylates RboP-WTA with glucose, instead of -acetylglucosamine (GlcNAc) by TarM(Sa) in . Replacement of GlcNAc with glucose in RboP-WTA impairs HA-MRSE detection by human immunoglobulin G, which may contribute to the immune-evasion capacities of many invasive . Crystal structures of complexes with uridine diphosphate glucose (UDP-glucose), and with UDP and glycosylated poly(RboP), reveal the binding mode and glycosylation mechanism of this enzyme and explain why TarM(Se) and TarM(Sa) link different sugars to poly(RboP). These structural data provide evidence that TarM(Se) is a processive WTA glycosyltransferase. Our study will support the targeted inhibition of TarM enzymes, and the development of RboP-WTA targeting vaccines and phage therapies.
Topics: Humans; Glycosyltransferases; Staphylococcus aureus; Staphylococcus epidermidis; Teichoic Acids; Uridine Diphosphate; Glucose; Phosphates
PubMed: 38000019
DOI: 10.1126/sciadv.adj2641 -
Graefe's Archive For Clinical and... Oct 2023Hydroxychloroquine (HCQ) is used in the treatment of several diseases, such as malaria, Sjögren's disease, Covid-19, and rheumatoid arthritis. However, HCQ induces...
Curcumin attenuates hydroxychloroquine-mediated apoptosis and oxidative stress via the inhibition of TRPM2 channel signalling pathways in a retinal pigment epithelium cell line.
PURPOSE
Hydroxychloroquine (HCQ) is used in the treatment of several diseases, such as malaria, Sjögren's disease, Covid-19, and rheumatoid arthritis. However, HCQ induces retinal pigment epithelium death via the excessive increase of cytosolic (cROS) and mitochondrial (mROS) free oxygen radical production. The transient receptor potential melastatin 2 (TRPM2) cation channel is stimulated by ADP-ribose (ADPR), cROS, and mROS, although it is inhibited by curcumin (CRC). We aimed to investigate the modulating action of CRC on HCQ-induced TRPM2 stimulation, cROS, mROS, apoptosis, and death in an adult retinal pigment epithelial 19 (ARPE19) cell line model.
MATERIAL AND METHODS
ARPE19 cells were divided into four groups: control (CNT), CRC (5 µM for 24 h), HCQ (60 µM for 48 h), and CRC + HCQ groups.
RESULTS
The levels of cell death (propidium iodide positive cell numbers), apoptosis markers (caspases -3, -8, and -9), oxidative stress (cROS and mROS), mitochondria membrane depolarization, TRPM2 current density, and intracellular free Ca and Zn fluorescence intensity were upregulated in the HCQ group after stimulation with hydrogen peroxide and ADPR, but their levels were downregulated by treatments with CRC and TRPM2 blockers (ACA and carvacrol). The HCQ-induced decrease in retinal live cell count and cell viability was counteracted by treatment with CRC.
CONCLUSION
HCQ-mediated overload Ca influx and retinal oxidative toxicity were induced in an ARPE19 cell line through the stimulation of TRPM2, although they were attenuated by treatment with CRC. Hence, CRC may be a potential therapeutic antioxidant for TRPM2 activation and HCQ treatment-induced retinal oxidative injury and apoptosis.
Topics: Humans; Adenosine Diphosphate Ribose; Apoptosis; Calcium; Cell Line; COVID-19; COVID-19 Drug Treatment; Curcumin; Hydroxychloroquine; Oxidative Stress; Retinal Pigment Epithelium; TRPM Cation Channels
PubMed: 37099129
DOI: 10.1007/s00417-023-06082-5