Bone Marrow Small Molecule Radioprotectors.

Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 4096-4096
Author(s):  
Michael W. Epperly ◽  
Darcy Franicola ◽  
Tracy Dixon ◽  
Xichen Zhang ◽  
Paavani Komanduri ◽  
...  
Keyword(s):  
Small Molecules ◽  
Small Molecule ◽  
Survival Curve ◽  
Radiation Sensitivity ◽  
Whole Body ◽  
Linear Quadratic ◽  
National Priority ◽  
Radioprotective Properties

Abstract Development of small molecule radioprotectors is a major national priority. Two groups of compounds have particular promise. The first group targets the mitochondria based upon previous data with transgene MnSOD which when expressed in the mitochondria prevents apoptosis and increases radioprotection. These agents contain the antioxidant tempol or nitric oxide synthetase inhibitor 2-amino-5,6-dihydro-6-methyl-4H-1,3-thiazine (AMT) attached to a hemi-gramicidin linker which targets the mitochondria. The second group consists of the dietary agent resveratrol and acetylated variants. Mouse hematopoietic progenitor 32Dcl3 cells were incubated for 1 hr in 10 μM tempol, AMT, or gramicidin linked tempol XJB-5-125 (tempol), XJB-7-75 (tempol) or JP4-039 (AMT). In separate experiments, 32Dcl3 cells were incubated for 1 hr in resveratrol or acetylated resveratrol. The cells were then irradiated to doses ranging from 0 to 8 Gy, plated in 0.8% methylcellulose, and incubated in a 5% CO2 incubator for 7 days. Colonies of greater than 50 cells were counted with the data analyzed using linear quadratic or single-hit, multi-target models. 32Dcl3 cells incubated in 10 μm tempol before irradiation resulted in no change in radiation sensitivity while incubation in XJB-5-125 or XJB-7-75 had decreased radiosensitivity. XJB-5-125 had an increased Do of 1.91 ± 0.67 Gy compared to 1.32 ± 0.09 Gy for 32Dcl3 cells incubated in tempol and 1.35 ± 0.27 Gy for control 32Dcl3 cells (p = 0.045 or 0.040, respectively). Incubation in XJB-5-75 resulted in an increased shoulder on the survival curve with an ñ of 19.4 ± 2.6 compared to 8.7 + 1.6 for cells incubated in tempol or 6.9 +1.8 for control 32Dcl3 cells (p = 0.025 or 0.022). Incubation in JP4-039 resulted in an increased Do of 2.2 ± 0.1 Gy compared to 1.24 ± 0.15 or 1.13 ± 0.06 for cells incubated in AMT or control 32Dcl3 cells only, respectively (p = 0.0115 or 0.0098, respectively). Incubation of 32Dcl3 cells in resveratrol or acetylated resveratrol before irradiation resulted in an increased shoulder on the survival curve of 33.2 ± 5.7 or 57.5 ± 9.9, respectively, compared to 6.9 ± 1.8 for 32Dcl3 cells (p = 0.0122 or 0.0072, respectively). These compounds were tested in mice receiving an LD50/30 irradiation dose. C57BL/6NHsd mice were injected intraperitoneally with 10 mg/kg of XJB-5-125, XJB-7-75or JP4-039 or 25 mg/kg of resveratrol or acetylated resveratrol and irradiated 10 mins later along with control mice to 9.5 Gy whole body irradiation. The mice injected with XJB-5-125, XJB-7-75, JP4-039 or acetylated-resveratrol had increased survival compared to control irradiated mice (p ≤ 0.0004). Therefore, four new small molecules have been identified which demonstrate significant radioprotective properties both in vitro and in vivo.

A correlation between radiation sensitivity and initial chromatid breaks in cancer cell lines revealed by Calyculin A-induced premature condensation

2006 ◽  
Vol 1 (3) ◽  
pp. 451-462 ◽  
Author(s):  
Jianshe Yang ◽  
Xigang Jing ◽  
Zhuanzi Wang ◽  
Wenjian Li
Keyword(s):  
Cell Lines ◽  
Radiation Sensitivity ◽  
Calyculin A ◽  
Linear Quadratic ◽  
Technique Survival ◽  
Positive Linear Correlation ◽  
Radiation Induced ◽  
Clinical Radiotherapy

AbstractThree human malignancy cell lines were irradiated with 60Co γ-rays. Initial chromatid breaks were measured by using the chemically induced premature chromosome condensation technique. Survival curves of cells exposed to gamma rays was linear-quadratic while the efficiency of Calyculin A in inducing PCC of G2 PCC was about five times more than G1 PCC. A dose-dependent increase in radiation-induced chromatid/isochromatid breaks was observed in G1 and G2 phase PCC and a nearly positive linear correlation was found between cell survival and chromatin breaks. This study implies that low LET radiation-induced chromatid/isochromatid breaks can potentially be used to predict the radiosensitivity of tumor cells either in in vitro experimentation or in in vivo clinical radiotherapy.

scholarly journals Small molecules that inhibit TNF signalling by stabilising an asymmetric form of the trimer

2019 ◽  
Vol 10 (1) ◽  
Author(s):  
James O’Connell ◽  
John Porter ◽  
Boris Kroeplien ◽  
Tim Norman ◽  
Stephen Rapecki ◽  
...  
Keyword(s):  
Small Molecules ◽  
Small Molecule ◽  
Protein Interactions ◽  
General Mechanism ◽  
Protein Protein Interactions ◽  
Biologic Drugs ◽  
Small Molecule Drugs ◽  
Necrosis Factor

AbstractTumour necrosis factor (TNF) is a cytokine belonging to a family of trimeric proteins; it has been shown to be a key mediator in autoimmune diseases such as rheumatoid arthritis and Crohn’s disease. While TNF is the target of several successful biologic drugs, attempts to design small molecule therapies directed to this cytokine have not led to approved products. Here we report the discovery of potent small molecule inhibitors of TNF that stabilise an asymmetrical form of the soluble TNF trimer, compromising signalling and inhibiting the functions of TNF in vitro and in vivo. This discovery paves the way for a class of small molecule drugs capable of modulating TNF function by stabilising a naturally sampled, receptor-incompetent conformation of TNF. Furthermore, this approach may prove to be a more general mechanism for inhibiting protein–protein interactions.

Transfection of Bone Marrow Cells In Vitro or In Vivo Prior to Cryopreservation with Manganese Superoxide Dismutase (MnSOD-PL) Protects Frozen Cells from Ionizing Irradiation.

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 5151-5151
Author(s):  
Michael W. Epperly ◽  
Laura D. Epperly ◽  
Darcy Franicola ◽  
Xicheng Zhang ◽  
Tracey Smith ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Manganese Superoxide Dismutase ◽  
Bone Marrow Cells ◽  
Survival Curve ◽  
Hematopoietic Progenitor Cell ◽  
Ionizing Irradiation ◽  
Linear Quadratic ◽  
Cytotoxic Stress

Abstract Overexpression of MnSOD in IL-3 dependent murine hematopoietic progenitor cell line 32D cl 3 protects against apoptosis induced by ionizing irradiation, TNF-α, IL-3 withdrawal or other inducers of cytotoxic stress. Cryopreservaton of bone marrow is routinely used in clinical marrow transplantation with the necessary cytotoxic loss of a fraction of cells from the stress of thawing. To determine if overexpression of MnSOD protected marrow from the stress of thawing and also whether frozen cells resisted ionizing irradiation, 32D cl 3 and subclone 2C6 stably transfected and overexpressing MnSOD were tested. Exponentially growing cells 2C6 cells demonstrate increased irradiation survival with an increased shoulder on the survival curve n = 4.95 ± 0.1 compared to 32D cl 3 n = 2.77 ± 0.1 (p = 0.011), with no significant change in the Do = 2.11 ± 0.08 vs. Do = 2.36 ± 0.10 Gy. Cells from 32D cl 3 and 2C6 were frozen in liquid nitrogen in 50% DMSO and stored at a −140°C for a minimum of 24 hrs and irradiated to doses ranging from 0 to 800 cGy while frozen. The cells were thawed 24 hr later, plated in methylcellulose and colonies of greater than 50 cells counted seven days later. The data was analyzed using linear quadratic and single-hit, multi-target models. Cells from 2C6 were more resistant to thawing with survival of 24.3 ± 0.6% compared to 20.9 ± 0.8% for 32D cl 3 (p = 0.018) and to irradiation as shown by an increase in the Do of 2.036 ± 0.225 compared to 1.455 ± 0.149 Gy for frozen 32D cl 3 cells (p= 0.0287). The frozen 2C6 cells resisted the stress of thawing with an increased plating efficiency compared to the frozen 32D cl 3 cells (121.4 ± 3.2 colonies for 2C6 cells and 104.3 ± 3.9 colonies for 32D cl 3 per 500 cells plated, p=0.0018). To determine whether fresh bone marrow transfected in vivo, or in vitro, then frozen and irradiated, also was protected, C57BL/6NHsd mice were injected with MnSOD-PL (100 ug plasmid DNA in 100 μl). Twenty-four hours later, bone marrow was isolated from MnSOD-PL injected mice as well as control mice (a subpopulation transfected with MnSOD-PL in vitro) and frozen in aliquots of 1 × 106 cells. The cells were irradiated while frozen to doses ranging from 0 to 800 cGy, plated in methylcellulose and colonies of greater than 50 cells counted 7 days later. The colonies were divided between nonadherent and adherent in the methylcellulose. The Do was calculated for the adherent colonies, nonadherent colonies and total colonies. In all three cases the Do for the bone marrow treated with MnSOD-PL in vitro or in vivo was higher than the Do of the control bone marrow. The percent HA-epitope tagged total transfected cells was 22.1 ± 3.7%. The data indicates that MnSOD overexpression protects frozen bone marrow perhaps important to increasing preservation efficiency.

scholarly journals A therapeutic combination of two small molecule toxin inhibitors provides broad preclinical efficacy against viper snakebite

2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Laura-Oana Albulescu ◽  
Chunfang Xie ◽  
Stuart Ainsworth ◽  
Jaffer Alsolaiss ◽  
Edouard Crittenden ◽  
...  
Keyword(s):  
Small Molecules ◽  
Small Molecule ◽  
Interspecific Variation ◽  
Medical Emergency ◽  
Dual Inhibitor ◽  
In Vivo Models ◽  
Mortality And Morbidity ◽  
Inhibitor Combination

AbstractSnakebite is a medical emergency causing high mortality and morbidity in rural tropical communities that typically experience delayed access to unaffordable therapeutics. Viperid snakes are responsible for the majority of envenomings, but extensive interspecific variation in venom composition dictates that different antivenom treatments are used in different parts of the world, resulting in clinical and financial snakebite management challenges. Here, we show that a number of repurposed Phase 2-approved small molecules are capable of broadly neutralizing distinct viper venom bioactivities in vitro by inhibiting different enzymatic toxin families. Furthermore, using murine in vivo models of envenoming, we demonstrate that a single dose of a rationally-selected dual inhibitor combination consisting of marimastat and varespladib prevents murine lethality caused by venom from the most medically-important vipers of Africa, South Asia and Central America. Our findings support the translation of combinations of repurposed small molecule-based toxin inhibitors as broad-spectrum therapeutics for snakebite.

scholarly journals Conversion of stem cells from apical papilla into endothelial cells by small molecules and growth factors

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Baicheng Yi ◽  
Tian Ding ◽  
Shan Jiang ◽  
Ting Gong ◽  
Hitesh Chopra ◽  
...  
Keyword(s):  
Stem Cells ◽  
Endothelial Cells ◽  
Growth Factors ◽  
Small Molecules ◽  
Adhesion Molecules ◽  
Small Molecule ◽  
Cell Type ◽  
Apical Papilla

Abstract Objectives Recently, a new strategy has been developed to directly reprogram one cell type towards another targeted cell type using small molecule compounds. Human fibroblasts have been chemically reprogrammed into neuronal cells, Schwann cells and cardiomyocyte-like cells by different small molecule combinations. This study aimed to explore whether stem cells from apical papilla (SCAP) could be reprogrammed into endothelial cells (ECs) using the same strategy. Materials and methods The expression level of endothelial-specific genes and proteins after chemical induction of SCAP was assessed by RT-PCR, western blotting, flow cytometry and immunofluorescence. The in vitro functions of SCAP-derived chemical-induced endothelial cells (SCAP-ECs) were evaluated by tube-like structure formation assay, acetylated low-density lipoprotein (ac-LDL) uptake and NO secretion detection. The proliferation and the migration ability of SCAP-ECs were evaluated by CCK-8 and Transwell assay. LPS stimulation was used to mimic the inflammatory environment in demonstrating the ability of SCAP-ECs to express adhesion molecules. The in vivo Matrigel plug angiogenesis assay was performed to assess the function of SCAP-ECs in generating vascular structures using the immune-deficient mouse model. Results SCAP-ECs expressed upregulated endothelial-specific genes and proteins; displayed endothelial transcriptional networks; exhibited the ability to form functional tubular-like structures, uptake ac-LDL and secrete NO in vitro; and contributed to generate blood vessels in vivo. The SCAP-ECs could also express adhesion molecules in the pro-inflammatory environment and have a similar migration and proliferation ability as HUVECs. Conclusions Our study demonstrates that the set of small molecules and growth factors could significantly promote endothelial transdifferentiation of SCAP, which provides a promising candidate cell source for vascular engineering and treatment of ischemic diseases.

scholarly journals CMH-Small Molecule Docks into SIRT1, Elicits Human IPF-Lung Fibroblast Cell Death, Inhibits Ku70-deacetylation, FLIP and Experimental Pulmonary Fibrosis

Biomolecules ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 997
Author(s):  
Jenya Konikov-Rozenman ◽  
Raphael Breuer ◽  
Naftali Kaminski ◽  
Shulamit B. Wallach-Dayan
Keyword(s):  
Pulmonary Fibrosis ◽  
Small Molecules ◽  
Structural Biology ◽  
Small Molecule ◽  
Fibroblast Cell ◽  
Regenerative Capacity ◽  
Activity Inhibition ◽  
Nonhistone Substrate

Regenerative capacity in vital organs is limited by fibrosis propensity. Idiopathic pulmonary fibrosis (IPF), a progressive lung disease linked with aging, is a classic example. In this study, we show that in flow cytometry, immunoblots (IB) and in lung sections, FLIP levels can be regulated, in vivo and in vitro, through SIRT1 activity inhibition by CMH (4-(4-Chloro-2-methylphenoxy)-N-hydroxybutanamide), a small molecule that, as we determined here by structural biology calculations, docked into its nonhistone substrate Ku70-binding site. Ku70 immunoprecipitations and immunoblots confirmed our theory that Ku70-deacetylation, Ku70/FLIP complex, myofibroblast resistance to apoptosis, cell survival, and lung fibrosis in bleomycin-treated mice, are reduced and regulated by CMH. Thus, small molecules associated with SIRT1-mediated regulation of Ku70 deacetylation, affecting FLIP stabilization in fibrotic-lung myofibroblasts, may be a useful strategy, enabling tissue regeneration.

Conjugates of Classical DNA/RNA Binder with Nucleobase: Chemical, Biochemical and Biomedical Applications

2019 ◽  
Vol 26 (30) ◽  
pp. 5609-5624
Author(s):  
Dijana Saftić ◽  
Željka Ban ◽  
Josipa Matić ◽  
Lidija-Marija Tumirv ◽  
Ivo Piantanida
Keyword(s):  
Molecular Weight ◽  
Small Molecules ◽  
Biomedical Applications ◽  
Protein Targets ◽  
New Class ◽  
Rna Targets ◽  
Covalently Linked ◽  
Structural Aspects

: Among the most intensively studied classes of small molecules (molecular weight < 650) in biomedical research are small molecules that non-covalently bind to DNA/RNA, and another intensively studied class is nucleobase derivatives. Both classes have been intensively elaborated in many books and reviews. However, conjugates consisting of DNA/RNA binder covalently linked to nucleobase are much less studied and have not been reviewed in the last two decades. Therefore, this review summarized reports on the design of classical DNA/RNA binder – nucleobase conjugates, as well as data about their interactions with various DNA or RNA targets, and even in some cases protein targets are involved. According to these data, the most important structural aspects of selective or even specific recognition between small molecule and target are proposed, and where possible related biochemical and biomedical aspects were discussed. The general conclusion is that this, rather new class of molecules showed an amazing set of recognition tools for numerous DNA or RNA targets in the last two decades, as well as few intriguing in vitro and in vivo selectivities. Several lead research lines show promising advancements toward either novel, highly selective markers or bioactive, potentially druggable molecules.

Use of Toxicokinetics in Risk Assessment Based on In Vitro Data

1993 ◽  
Vol 21 (2) ◽  
pp. 173-180
Author(s):  
Gunnar Johanson
Keyword(s):  
Risk Assessment ◽  
Whole Body ◽  
External Exposure ◽  
Target Dose ◽  
Toxic Response ◽  
Route Of Exposure ◽  
Vitro Data ◽  
In Vitro Data

This presentation addresses some aspects of the methodology, advantages and problems associated with toxicokinetic modelling based on in vitro data. By using toxicokinetic models, particularly physiologically-based ones, it is possible, in principle, to describe whole body toxicokinetics, target doses and toxic effects from in vitro data. Modelling can be divided into three major steps: 1) to relate external exposure (applied dose) of xenobiotic to target dose; 2) to establish the relationship between target dose and effect (in vitro data, e.g. metabolism in microsomes, partitioning in tissue homogenates, and toxicity in cell cultures, are useful in both steps); and 3) to relate external exposure to toxic effect by combining the first two steps. Extrapolations from in vitro to in vivo, between animal and man, and between high and low doses, can easily be carried out by toxicokinetic simulations. In addition, several factors that may affect the toxic response by changing the target dose, such as route of exposure and physical activity, can be studied. New insights concerning the processes involved in toxicity often emerge during the design, refinement and validation of the model. The modelling approach is illustrated by two examples: 1) the carcinogenicity of 1,3-butadiene; and 2) the haematotoxicity of 2-butoxyethanol. Toxicokinetic modelling is an important tool in toxicological risk assessment based on in vitro data. Many factors, some of which can, and should be, studied in vitro, are involved in the expression of toxicity. Successful modelling depends on the identification and quantification of these factors.

scholarly journals Adipocyte PHLPP2 inhibition prevents obesity-induced fatty liver

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
KyeongJin Kim ◽  
Jin Ku Kang ◽  
Young Hoon Jung ◽  
Sang Bae Lee ◽  
Raffaela Rametta ◽  
...  
Keyword(s):  
Fatty Liver ◽  
Whole Body ◽  
Acid Oxidation ◽  
Chow Diet ◽  
Peroxisome Proliferator ◽  
Obese Mice ◽  
Ph Domain ◽  
Peroxisome Proliferator Activated Receptor

AbstractIncreased adiposity confers risk for systemic insulin resistance and type 2 diabetes (T2D), but mechanisms underlying this pathogenic inter-organ crosstalk are incompletely understood. We find PHLPP2 (PH domain and leucine rich repeat protein phosphatase 2), recently identified as the Akt Ser473 phosphatase, to be increased in adipocytes from obese mice. To identify the functional consequence of increased adipocyte PHLPP2 in obese mice, we generated adipocyte-specific PHLPP2 knockout (A-PHLPP2) mice. A-PHLPP2 mice show normal adiposity and glucose metabolism when fed a normal chow diet, but reduced adiposity and improved whole-body glucose tolerance as compared to Cre- controls with high-fat diet (HFD) feeding. Notably, HFD-fed A-PHLPP2 mice show increased HSL phosphorylation, leading to increased lipolysis in vitro and in vivo. Mobilized adipocyte fatty acids are oxidized, leading to increased peroxisome proliferator-activated receptor alpha (PPARα)-dependent adiponectin secretion, which in turn increases hepatic fatty acid oxidation to ameliorate obesity-induced fatty liver. Consistently, adipose PHLPP2 expression is negatively correlated with serum adiponectin levels in obese humans. Overall, these data implicate an adipocyte PHLPP2-HSL-PPARα signaling axis to regulate systemic glucose and lipid homeostasis, and suggest that excess adipocyte PHLPP2 explains decreased adiponectin secretion and downstream metabolic consequence in obesity.

Sign in / Sign up

Export Citation Format

Share Document