Publications 

June 2020

Evaluation of the NAD + Biosynthetic Pathway in ALS Patients and Effect of Modulating NAD + Levels in hSOD1-linked ALS Mouse Models

Amyotrophic lateral sclerosis (ALS) is characterized by progressive degeneration of motor neurons. Astrocytes from diverse ALS models induce motor neuron death in co-culture. Enhancing NAD+ availability, or increasing the expression of the NAD+-dependent deacylases SIRT3 and SIRT6, abrogates their neurotoxicity in cell culture models. To determine the effect of increasing NAD+ availability in ALS mouse models we used two strategies, ablation of a NAD+-consuming enzyme (CD38) and supplementation with a bioavailable NAD+ precursor (nicotinamide riboside, NR). Deletion of CD38 had no effect in the survival of two hSOD1-linked ALS mouse models. On the other hand, NR-supplementation delayed motor neuron degeneration, decreased markers of neuroinflammation in the spinal cord, appeared to modify muscle metabolism and modestly increased the survival of hSOD1G93A mice. In addition, we found altered expression of enzymes involved in NAD+ synthesis (NAMPT and NMNAT2) and decreased SIRT6 expression in the spinal cord of ALS patients, suggesting deficits of this neuroprotective pathway in the human pathology. Our data denotes the therapeutic potential of increasing NAD+ levels in ALS. Moreover, the results indicate that the approach used to enhance NAD+ levels critically defines the biological outcome in ALS models, suggesting that boosting NAD+ levels with the use of bioavailable precursors would be the preferred therapeutic strategy for ALS.

Harlan BA, Killoy KM, Pehar M, Liu L, Auwerx J, Vargas MR. Evaluation of the NAD+ biosynthetic pathway in ALS patients and effect of modulating NAD+ levels in hSOD1-linked ALS mouse models. Exp Neurol. 2020;327:113219. doi:10.1016/j.expneurol.2020.113219

https://pubmed.ncbi.nlm.nih.gov/32014438/

Extracellular Matrix Alterations in Low-Grade Lung Adenocarcinoma Compared With Normal Lung Tissue by Imaging Mass Spectrometry

Lung adenocarcinoma (LUAD) is the second most common cancer, affecting both men and women. Fibrosis is a hallmark of LUAD occurring throughout progression with excess production of extracellular matrix (ECM) components that lead to metastatic cell processes. Understanding the ECM cues that drive LUAD progression has been limited due to a lack of tools that can access and report on ECM components within the complex tumor microenvironment. Here, we test whether low-grade LUAD can be distinguished from normal lung tissue using a novel ECM imaging mass spectrometry (ECM IMS) approach. ECM IMS analysis of a tissue microarray with 20 low-grade LUAD tissues and 20 normal lung samples from 10 patients revealed 25 peptides that could discriminate between normal and low-grade LUAD using area under the receiver-operating curve (AUC) ≥0.7, P value ≤.001. Principal component analysis demonstrated that 62.4% of the variance could be explained by sample origin from normal or low-grade tumor tissue. Additional work performed on a wedge resection with moderately differentiated LUAD demonstrated that the ECM IMS analytical approach could distinguish LUAD spectral features from spectral features of normal adjacent lung tissue. Conventional liquid chromatography with tandem mass spectrometry (LC-MS/MS) proteomics demonstrated that specific sites of hydroxylation of proline (HYP) were a main collagen post translational modification that was readily detected in LUAD. A distinct peptide from collagen 3A1 modified by HYP was increased 3.5 fold in low-grade LUAD compared with normal lung tissue (AUC 0.914, P value <.001). this="" suggests="" that="" regulation="" of="" collagen="" proline="" hydroxylation="" could="" be="" an="" important="" process="" during="" early="" luad="" fibrotic="" deposition.="" ecm="" ims="" is="" a="" useful="" tool="" that="" may="" be="" used="" to="" define="" fibrotic="" deposition="" in="" low-grade="">

Angel PM, Bruner E, Bethard J, et al. Extracellular matrix alterations in low-grade lung adenocarcinoma compared with normal lung tissue by imaging mass spectrometry. J Mass Spectrom. 2020;55(4):e4450. doi:10.1002/jms.4450Robinson RM, Reyes L, Duncan RM, et al. Tuning isoform selectivity and bortezomib sensitivity with a new class of alkenyl indene PDI inhibitor. Eur J Med Chem. 2020;186:111906. doi:10.1016/j.ejmech.2019.111906

https://pubmed.ncbi.nlm.nih.gov/31654589/

Long-term Effect of the Perindopril/Indapamide/Amlodipine Single-Pill Combination on Left Ventricular Hypertrophy in Outpatient Hypertensive Subjects

Background: Most antihypertensive drugs used in monotherapy or in combination therapy reduce the left ventricular mass index (LVMI). However, little is known about the effects on LVMI of a triple fixed-dose combination (TFC) therapy, containing in a single pill an angiotensin-converting enzyme inhibitor (ACEI), a diuretic and a calcium channel blocker (CCB).

Methods: In this prospective open-label study, 92 patients with essential hypertension were randomized to treatment with a TFC of perindopril/indapamide/amlodipine at different doses or a triple free combination therapy (FCT) including ACEI/diuretic/CCB. Office blood pressure (BP) measurement, 24 h-ambulatory BP monitoring and echocardiography were performed at baseline and during a 14-month follow-up. The BP variability (BPV) over 24 h was calculated as ± standard deviation of the daytime systolic BP. Differences between office and monitored BP and LVMI were evaluated by ANOVA for repeated measures.

Results: A significant BP-lowering effect was observed for both treatments. At follow-up, BPV was reduced in both the treatment groups vs. the baseline (14.0±1.5 vs. 17.0±1.8 and 16.2±2.1 vs. 17.6±2.3, respectively), but it was lower in the TFC vs. the FCT group (14.0±1.5 vs. 16.1±2.2, P < 0.05).="" lvmi="" was="" lower="" in="" both="" the="" treatment="" groups,="" but="" the="" change="" was="" greater="" for="" tfc="" vs.="" fct="" (-8.3±4.9%="" vs.="" -2.0="" ±2.1%,="" p="">< 0.0001).="" left="" ventricular="" hypertrophy="" (lvh)="" regression="" was="" greater="" in="" the="" tfc="" vs.="" the="" fct="" group="" (43.5%="" vs.="" 30.4%,="" p=""><>

Conclusions: Independently of BP values achieved, the antihypertensive TFC therapy was more effective than FCT in LVMI reduction and LVH regression, possibly related to drugs' intrinsic properties and to BPV modulation.

Mazza A, Townsend DM, Schiavon L, et al. Long-term effect of the perindopril/indapamide/amlodipine single-pill combination on left ventricular hypertrophy in outpatient hypertensive subjects. Biomed Pharmacother. 2019;120:109539. doi:10.1016/j.biopha.2019.109539

https://pubmed.ncbi.nlm.nih.gov/31654589/

Human Cardiac Organoids for the Modelling of Myocardial Infarction and Drug Cardiotoxicity

Environmental factors are the largest contributors to cardiovascular disease. Here we show that cardiac organoids that incorporate an oxygen-diffusion gradient and that are stimulated with the neurotransmitter noradrenaline model the structure of the human heart after myocardial infarction (by mimicking the infarcted, border and remote zones), and recapitulate hallmarks of myocardial infarction (in particular, pathological metabolic shifts, fibrosis and calcium handling) at the transcriptomic, structural and functional levels. We also show that the organoids can model hypoxia-enhanced doxorubicin cardiotoxicity. Human organoids that model diseases with non-genetic pathological factors could help with drug screening and development.

Richards DJ, Li Y, Kerr CM, et al. Human cardiac organoids for the modelling of myocardial infarction and drug cardiotoxicity. Nat Biomed Eng. 2020;4(4):446‐462. doi:10.1038/s41551-020-0539-4

https://pubmed.ncbi.nlm.nih.gov/32284552/

Suppression of Iron Mobilization From Lysosomes to Mitochondria Attenuates Liver Injury After Acetaminophen Overdose in Vivo in Mice: Protection by Minocycline

Acetaminophen (APAP) overdose causes hepatotoxicity involving mitochondrial dysfunction. Previous studies showed that translocation of Fe2+ from lysosomes into mitochondria by the mitochondrial Ca2+ uniporter (MCU) promotes the mitochondrial permeability transition (MPT) after APAP. Here, our Aim was to assess protection by iron chelation and MCU inhibition against APAP hepatotoxicity in mice. C57BL/6 mice and hepatocytes were administered toxic doses of APAP with and without starch-desferal (an iron chelator), minocycline (MCU inhibitor), or N-acetylcysteine (NAC). In mice, starch-desferal and minocycline pretreatment decreased ALT and liver necrosis after APAP by >60%. At 24 h after APAP, loss of fluorescence of mitochondrial rhodamine 123 occurred in pericentral hepatocytes often accompanied by propidium iodide labeling, indicating mitochondrial depolarization and cell death. Starch-desferal and minocycline pretreatment decreased mitochondrial depolarization and cell death by more than half. In cultured hepatocytes, cell killing at 10 h after APAP decreased from 83% to 49%, 35% and 27%, respectively, by 1 h posttreatment with minocycline, NAC, and minocycline plus NAC. With 4 h posttreatment in vivo, minocycline and minocycline plus NAC decreased ALT and necrosis by ~20% and ~50%, respectively, but NAC alone was not effective. In conclusion, minocycline and starch-desferal decrease mitochondrial dysfunction and severe liver injury after APAP overdose, suggesting that the MPT is likely triggered by iron uptake into mitochondria through MCU. In vivo, minocycline and minocycline plus NAC posttreatment after APAP protect at later time points than NAC alone, indicating that minocycline has a longer window of efficacy than NAC.

Hu J, Lemasters JJ. Suppression of iron mobilization from lysosomes to mitochondria attenuates liver injury after acetaminophen overdose in vivo in mice: Protection by minocycline. Toxicol Appl Pharmacol. 2020;392:114930. doi:10.1016/j.taap.2020.114930

https://pubmed.ncbi.nlm.nih.gov/32109512/

Tuning Isoform Selectivity and Bortezomib Sensitivity With a New Class of Alkenyl Indene PDI Inhibitor

Protein disulfide isomerase (PDI, PDIA1) is an emerging therapeutic target in oncology. PDI inhibitors have demonstrated a unique propensity to selectively induce apoptosis in cancer cells and overcome resistance to existing therapies, although drug candidates have not yet progressed to the stage of clinical development. We recently reported the discovery of lead indene compound E64FC26 as a potent pan-PDI inhibitor that enhances the cytotoxic effects of proteasome inhibitors in panels of Multiple Myeloma (MM) cells and MM mouse models. An extensive medicinal chemistry program has led to the generation of a diverse library of indene-containing molecules with varying degrees of proteasome inhibitor potentiating activity. These compounds were generated by a novel nucleophilic aromatic ring cyclization and dehydration reaction from the precursor ketones. The results provide detailed structure activity relationships (SAR) around this indene pharmacophore and show a high degree of correlation between potency of PDI inhibition and bortezomib (Btz) potentiation in MM cells. Inhibition of PDI leads to ER and oxidative stress characterized by the accumulation of misfolded poly-ubiquitinated proteins and the induction of UPR biomarkers ATF4, CHOP, and Nrf2. This work characterizes the synthesis and SAR of a new chemical class and further validates PDI as a therapeutic target in MM as a single agent and in combination with proteasome inhibitors.

Robinson RM, Reyes L, Duncan RM, et al. Tuning isoform selectivity and bortezomib sensitivity with a new class of alkenyl indene PDI inhibitor. Eur J Med Chem. 2020;186:111906. doi:10.1016/j.ejmech.2019.111906

https://pubmed.ncbi.nlm.nih.gov/31787362/

December 2019

Endoplasmic Reticulum Protein Disulfide Isomerase Shapes T Cell Efficacy for Adoptive Cellular Therapy of Tumors

Effective cancer therapies simultaneously restrict tumor cell growth and improve anti-tumor immune responses. Targeting redox-dependent protein folding enzymes within the endoplasmic reticulum (ER) is an alternative approach to activation of the unfolded protein response (UPR) and a novel therapeutic platform to induce malignant cell death. E64FC26 is a recently identified protein disulfide isomerase (PDI) inhibitor that activates the UPR, oxidative stress, and apoptosis in tumor cells, but not normal cell types. Given that targeting cellular redox homeostasis is a strategy to augment T cell tumor control, we tested the effect of E64FC26 on healthy and oncogenic T cells. In stark contrast to the pro-UPR and pro-death effects we observed in malignant T cells, we found that E64FC26 improved viability and limited the UPR in healthy T cells. E64FC26 treatment also diminished oxidative stress and decreased global PDI expression in normal T cells. Oxidative stress and cell death are limited in memory T cells and we found that PDI inhibition promoted memory traits and reshaped T cell metabolism. Using adoptive transfer of tumor antigen-specific CD8 T cells, we demonstrate that T cells activated and expanded in the presence of E64FC26 control tumor growth better than vehicle-matched controls. Our data indicate that PDI inhibitors are a new class of drug that may dually inhibit tumor cell growth and improve T cell tumor control.

https://pubmed.ncbi.nlm.nih.gov/31779147/?from_term=GM103542%5BGrant+Number%5D&from_sort=date&from_pos=5#

Thermosensitive Nanosystems Associated With Hyperthermia for Cancer Treatment

Conventional chemotherapy regimens have limitations due to serious adverse effects. Targeted drug delivery systems to reduce systemic toxicity are a powerful drug development platform. Encapsulation of antitumor drug(s) in thermosensitive nanocarriers is an emerging approach with a promise to improve uptake and increase therapeutic efficacy, as they can be activated by hyperthermia selectively at the tumor site. In this review, we focus on thermosensitive nanosystems associated with hyperthermia for the treatment of cancer, in preclinical and clinical use.

https://pubmed.ncbi.nlm.nih.gov/31775273/?from_term=GM103542%5BGrant+Number%5D&from_sort=date&from_pos=6

S-Glutathionylated Serine Proteinase Inhibitors as Biomarkers for Radiation Exposure in Prostate Cancer Patients

In biological tissues, radiation causes the formation of reactive oxygen species (ROS), some of which lead to sequential oxidation of certain protein cysteine residues. Resultant cysteinyl radicals are subject to post-translational modification through S-glutathionylation. The present clinical trial was designed to determine if S-glutathionylated serine protease inhibitors (serpins) in blood could be used as biomarkers of exposure to radiation. 56 male prostate cancer patients treated with radiotherapy were enrolled in the trial and levels of S-glutathionylated serpins A1 and A3 were assessed by immunoblotting. Patients were classified into three groups: (1) external beam radiation therapy (EBRT); (2) brachytherapy (BT); (3) both EBRT and BT. Prior to treatment, baseline plasma levels of both unmodified and S-glutathionylated serpins were similar in each group. We identified elevated plasma levels of S-glutathionylated serpin A1 monomer, trimer and serpin A3 monomer in patient blood following radiation. Maximal increased levels of these S-glutathionylated serpins were correlated with increased duration of radiotherapy treatments. We conclude that it is practical to quantify patient plasma S-glutathionylated serpins and that these post-translationally modified proteins are candidate biomarkers for measuring radiation exposure. This provides a platform for use of such biomarkers in trials with the range of drugs that, like radiation, produce ROS.

https://pubmed.ncbi.nlm.nih.gov/31551460/?from_term=GM103542%5BGrant+Number%5D&from_sort=date&from_pos=9

Post-translational S-glutathionylation of Cofilin Increases Actin Cycling During Cocaine Seeking

Neuronal defense against oxidative damage is mediated primarily by the glutathione redox system. Traditionally considered a mechanism to protect proteins from irreversible oxidation, mounting evidence supports a role for protein S-glutathionylation in cell signaling in response to changes in intracellular redox status. Here we determined the specific sites on the actin binding protein cofilin that undergo S-glutathionylation. In addition, we show that S-glutathionylation of cofilin reduces its capacity to depolymerize F-actin. We further describe an assay to determine the S-glutathionylation of target proteins in brain tissue from behaving rodents. Using this technique, we show that cofilin in the rat nucleus accumbens undergoes S-glutathionylation during 15-minutes of cued cocaine seeking in the absence of cocaine. Our findings demonstrate that cofilin S-glutathionylation is increased in response to cocaine-associated cues and that increased cofilin S-glutathionylation reduces cofilin-dependent depolymerization of F-actin. Thus, S-glutathionylation of cofilin may serve to regulate actin cycling in response to drug-conditioned cues.

https://pubmed.ncbi.nlm.nih.gov/31550273/?from_term=GM103542%5BGrant+Number%5D&from_sort=date&from_pos=10

A Rapid Array-Based Approach to N-Glycan Profiling of Cultured Cells

Typically, N-glycosylation studies done on cultured cells require up to millions of cells followed by lengthy preparation to release, isolate, and profile N-glycans. To overcome these limitations, we report a rapid array-based workflow for profiling N-glycan signatures from cells, adapted from imaging mass spectrometry used for on-tissue N-glycan profiling. Using this approach, N-glycan profiles from a low-density array of eight cell chambers could be reported within 4 h of completing cell culture. Approaches are demonstrated that account for background N-glycans due to serum media. Normalization procedures are shown. The method is robust and reproducible, requiring as few as 3000 cells per replicate with a 3-20% coefficient of variation to capture label-free profiles of N-glycans. Quantification by stable isotopic labeling of N-glycans in cell culture is demonstrated and adds no additional time to preparation. Utility of the method is demonstrated by measurement of N-glycan turnover rates due to induction of oxidative stress in human primary aortic endothelial cells. The developed method and ancillary tools serve as a foundational launching point for rapid profiling of N-glycans ranging from high-density arrays down to single cells in culture.

https://pubmed.ncbi.nlm.nih.gov/31535553/?from_term=GM103542%5BGrant+Number%5D&from_sort=date&from_page=2&from_pos=1

Low Dose of Chronic Ethanol Exposure in Adult Zebrafish Induces Hepatic Steatosis and Injury

Chronic alcohol consumption is a major cause of chronic liver disease worldwide. Adult zebrafish have emerged as a new vertebrate model of alcoholic liver disease. In previous research, a high dose of chronic ethanol treatment induced characteristic features of steatosis and hepatic injury in adult zebrafish, yet the ethanol concentration in that study was significantly higher than the lethal dose in humans. In the current study, we examined whether a low dose of chronic ethanol exposure in adult zebrafish induced the metabolic and pathological features seen in alcoholic liver disease. We found that chronic ethanol treatment at 0.2% ethanol (v/v) concentration for 4 weeks induced a significant elevation of serum glucose and triacylglycerol in adult zebrafish. In addition, serum alanine aminotransferase activity was significantly elevated after ethanol treatment. Histological analysis revealed steatosis and hepatocyte ballooning phenotype. Gene expression analysis using quantitative real-time PCR suggested that ethanol treatment induced inflammation, apoptosis, and fibrosis. In addition, we found significant increases in gene expression involved in glucose and lipid metabolism as well as mitochondrial biogenesis and function. Importantly, expression of genes involved in oxidative and endoplasmic reticulum stress, two major stress signaling pathways underlying hepatic injury in alcoholic liver disease, were highly upregulated in the livers of adult zebrafish after chronic ethanol treatment. In conclusion, we found that 4 weeks of low dose ethanol exposure leads to typical ethanol-induced liver disease, with pathological and gene expression patterns.

https://pubmed.ncbi.nlm.nih.gov/31387182/?from_term=GM103542%5BGrant+Number%5D&from_sort=date&from_page=2&from_pos=3

June 2019

Proximal Tubule β 2-Adrenergic Receptor Mediates Formoterol-Induced Recovery of Mitochondrial and Renal Function After Ischemia-Reperfusion Injury

Acute kidney injury (AKI) is the rapid loss of renal function after an insult, and renal proximal tubule cells (RPTCs) are central to the pathogenesis of AKI. The β 2-adrenergic receptor (β 2AR) agonist formoterol accelerates the recovery of renal function in mice after ischemia-reperfusion injury (IRI) with associated rescue of mitochondrial proteins; however, the cell type responsible for this recovery remains unknown. The role of RPTCs in formoterol-induced recovery of renal function was assessed in a proximal tubule-specific knockout of the β 2AR (γGT-Cre:ADRB2Flox/Flox). These mice and wild-type controls (ADRB2Flox/Flox) were subjected to renal IRI, followed by once-daily dosing of formoterol beginning 24 hours post-IRI and euthanized at 144 hours. Compared with ADRB2Flox/Flox mice, γGT-Cre:ADRB2Flox/Flox mice had decreased renal cortical mRNA expression of the β 2AR. After IRI, formoterol treatment restored renal function in ADRB2Flox/Flox but not γGT-Cre:ADRB2Flox/Flox mice as measured by serum creatinine, histopathology, and expression of kidney injury marker-1 (KIM-1). Formoterol-treated ADRB2Flox/Flox mice exhibited recovery of mitochondrial proteins and DNA copy number, whereas γGT-Cre:ADRB2Flox/Flox mice treated with formoterol did not. Analysis of mitochondrial morphology by transmission electron microscopy demonstrated that formoterol increased mitochondrial number and density in ADRB2Flox/Flox mice but not in γGT-Cre:ADRB2Flox/Flox mice. These data demonstrate that proximal tubule β 2AR regulates renal mitochondrial homeostasis. Formoterol accelerates the recovery of renal function after AKI by activating proximal tubule β 2AR to induce mitochondrial biogenesis and demonstrates the overall requirement of RPTCs in renal recovery.

https://pubmed.ncbi.nlm.nih.gov/30709866/?from_term=GM103542%5BGrant+Number%5D&from_sort=date&from_page=3&from_pos=7

3-ketodihydrosphingosine Reductase Mutation Induces Steatosis and Hepatic Injury in Zebrafish

3-ketodihydrosphingosine reductase (KDSR) is the key enzyme in the de novo sphingolipid synthesis. We identified a novel missense kdsrI105R mutation in zebrafish that led to a loss of function, and resulted in progression of hepatomegaly to steatosis, then hepatic injury phenotype. Lipidomics analysis of the kdsrI105R mutant revealed compensatory activation of the sphingolipid salvage pathway, resulting in significant accumulation of sphingolipids including ceramides, sphingosine and sphingosine 1-phosphate (S1P). Ultrastructural analysis revealed swollen mitochondria with cristae damage in the kdsrI105R mutant hepatocytes, which can be a cause of hepatic injury in the mutant. We found elevated sphingosine kinase 2 (sphk2) expression in the kdsrI105R mutant. Genetic interaction analysis with the kdsrI105R and the sphk2wc1 mutants showed that sphk2 depletion suppressed liver defects observed in the kdsrI105R mutant, suggesting that liver defects were mediated by S1P accumulation. Further, both oxidative stress and ER stress were completely suppressed by deletion of sphk2 in kdsrI105R mutants, linking these two processes mechanistically to hepatic injury in the kdsrI105R mutants. Importantly, we found that the heterozygous mutation in kdsr induced predisposed liver injury in adult zebrafish. These data point to kdsr as a novel genetic risk factor for hepatic injury.

https://pubmed.ncbi.nlm.nih.gov/30718751/?from_term=GM103542%5BGrant+Number%5D&from_sort=date&from_page=3&from_pos=6

Pharmacology of ME-344, a Novel Cytotoxic Isoflavone

Isoflavones isolated from members of the Fabaceae (primarily Leguminosae) family have been characterized for their phytoestrogenic properties, but certain derivatives have also shown potential as possible cancer therapeutic agents. ME-344, related to phenoxodiol (Fig. 1), is a second generation isoflavone with a recent history of both preclinical and early clinical testing. The drug has unusual cytotoxicity profiles, where cancer cell lines can be categorized as either intrinsically sensitive or resistant to the drug. Evolving studies show that the cytotoxic properties of the drug are enacted through targeting mitochondrial bioenergetics. While the drug has undergone early Phase I/II trials in solid tumors with confined dose limiting effects and some evidence of disease response, there is a continuing need to define specific cellular targets that determine sensitivity, with the long-term goal of applying such information to individualized therapy. This review article details some of the existing and ongoing studies that are assisting in the continued drug development processes that may lead to new drug application (NDA) status.

https://pubmed.ncbi.nlm.nih.gov/30885362/?from_term=GM103542%5BGrant+Number%5D&from_sort=date&from_page=3&from_pos=4

Statin-dependent Modulation of Mitochondrial Metabolism in Cancer Cells Is Independent of Cholesterol Content

Statins, widely used to treat hypercholesterolemia, inhibit the 3-hydroxy-3-methylglutaryl-coenzyme A reductase, the rate-limiting enzyme of de novo cholesterol (Chol) synthesis. Statins have been also reported to slow tumor progression. In cancer cells, ATP is generated both by glycolysis and oxidative phosphorylation. Mitochondrial membrane potential (ΔΨ), a readout of mitochondrial metabolism, is sustained by the oxidation of respiratory substrates in the Krebs cycle to generate NADH and flavin adenine dinucleotide, which are further oxidized by the respiratory chain. Here, we studied the short-term effects of statins (3-24 h) on mitochondrial metabolism on cancer cells. Lovastatin (LOV) and simvastatin (SIM) increased ΔΨ in HepG2 and Huh7 human hepatocarcinoma cells and HCC4006 human lung adenocarcinoma cells. Mitochondrial hyperpolarization after LOV and SIM was dose and time dependent. Maximal increase in ΔΨ occurred at 10 µM and 24 h for both statins. The structurally unrelated atorvastatin also hyperpolarized mitochondria in HepG2 cells. Cellular and mitochondrial Chol remained unchanged after SIM. Both LOV and SIM decreased basal respiration, ATP-linked respiration, and ATP production. LOV and SIM did not change the rate of lactic acid production. In summary, statins modulate mitochondrial metabolism in cancer cells independently of the Chol content in cellular membranes without affecting glycolysis.-Christie, C. F., Fang, D., Hunt, E. G., Morris, M. E., Rovini, A., Heslop, K. A., Beeson, G. C., Beeson, C. C., Maldonado, E. N. Statin-dependent modulation of mitochondrial metabolism in cancer cells is independent of cholesterol content.

https://pubmed.ncbi.nlm.nih.gov/30951369/?from_term=GM103542%5BGrant+Number%5D&from_sort=date&from_page=3&from_pos=3

Thioredoxin-1 Improves the Immunometabolic Phenotype of Antitumor T Cells

Adoptive transfer of tumor epitope-reactive T cells has emerged as a promising strategy to control tumor growth. However, chronically-stimulated T cells expanded for adoptive cell transfer are susceptible to cell death in an oxidative tumor microenvironment. Because oxidation of cell-surface thiols also alters protein functionality, we hypothesized that increasing the levels of thioredoxin (Trx), an antioxidant molecule facilitating reduction of proteins through cysteine thiol-disulfide exchange, in T cells will promote their sustained antitumor function. Using pre-melanosome protein (Pmel)-Trx1 transgenic mouse-derived splenic T cells, flow cytometry, and gene expression analysis, we observed here that higher Trx expression inversely correlated with reactive oxygen species and susceptibility to T-cell receptor restimulation or oxidation-mediated cell death. These Trx1-overexpressing T cells exhibited a cluster of differentiation 62Lhi (CD62Lhi) central memory-like phenotype with reduced glucose uptake (2-NBDGlo) and decreased effector function (interferon γlo). Furthermore, culturing tumor-reactive T cells in the presence of recombinant Trx increased the dependence of T cells on mitochondrial metabolism and improved tumor control. We conclude that strategies for increasing the antioxidant capacity of antitumor T cells modulate their immunometabolic phenotype leading to improved immunotherapeutic control of established tumors.

https://pubmed.ncbi.nlm.nih.gov/30971427/?from_term=GM103542%5BGrant+Number%5D&from_sort=date&from_page=3&from_pos=2