Reduced Adenosine Triphosphate Research Articles

Mannose inhibits the growth of prostate cancer through a mitochondrial mechanism.

The limited treatment options for advanced prostate cancer (PCa) lead to the urgent need to discover new anticancer drugs. Mannose, an isomer of glucose, has been reported to have an anticancer effect on various tumors. However, the anticancer effect of mannose in PCa remains unclear. In this study, we demonstrated that mannose inhibits the proliferation and promotes the apoptosis of PCa cells in vitro, and mannose was observed to have an anticancer effect in mice without harming their health. Accumulation of intracellular mannose simultaneously decreased the mitochondrial membrane potential, increased mitochondrial and cellular reactive oxygen species (ROS) levels, and reduced adenosine triphosphate (ATP) production in PCa cells. Mannose treatment of PCa cells induced changes in mitochondrial morphology, caused dysregulated expression of the fission protein, such as fission, mitochondrial 1 (FIS1), and enhanced the expression of proapoptotic factors, such as BCL2-associated X (Bax) and BCL2-antagonist/killer 1 (Bak). Furthermore, lower expression of mannose phosphate isomerase (MPI), the key enzyme in mannose metabolism, indicated poorer prognosis in PCa patients, and downregulation of MPI expression in PCa cells enhanced the anticancer effect of mannose. This study reveals the anticancer effect of mannose in PCa and its clinical significance in PCa patients.

DNA-Unresponsive Platinum(II) Complex Induces ERS-Mediated Mitophagy in Cancer Cells.

Mitophagy is a selective autophagic process that degrades dysfunctional mitochondria. Monofunctional platinum(II) complexes are candidates for anticancer drugs with the potential to circumvent the drug resistance and side effects of cisplatin and its analogues, but their mechanism of action is elusive. Complex Mono-Pt kills cancer cells through a mitophagic pathway. The mechanism involves the stimulation of endoplasmic reticulum stress (ERS) and activation of the unfolded protein response. Mono-Pt severely impairs the structure and function of mitochondria, including disruption of morphological integrity, dissipation of membrane potential, elevation of reactive oxygen species, inhibition of mtDNA transcription, and reduction of adenosine triphosphate (ATP), which ultimately leads to mitophagy. Mono-Pt does not react with nuclear DNA but exhibits potent antiproliferative activity against cancer cells, thus breaking the DNA-binding paradigm and classical structure-activity rules for platinum drugs. The ERS-mediated mitophagy provides an alternative mechanism for platinum complexes, which broadens the way for developing new platinum anticancer drugs.

Photoregulated plasmon enhanced controllable hydrogen sulfide delivery for photothermal augmented gas therapy

Gas therapy has emerged as a promising “green” treatment modality for malignant cancer, however, the targeted delivery of gas donors as well as the controlled gas release remain a formidable challenge. Herein, self-assembled gold nanovesicles (GVs) loaded with ammonium sulfide ((NH4)2S) (denoted as GV-(NH4)2S) were developed as theranostic nanoplatform for near-infrared (NIR)-activated in-situ hydrogen sulfide (H2S) generation, controllable gas delivery, and combined photothermal/gas therapy of cancer. GVs had the following features, (1) large hollow cavity, offering high encapsulation efficiency of (NH4)2S (∼95%), (2) strong plasmon coupling effect, promoting high photothermal effect under NIR laser irradiation. Upon laser irradiation, GVs were ruptured, thus allowing the simultaneous release and decomposition of (NH4)2S to generate H2S. The generated H2S induced significant mitochondrial damage and thus reduced adenosine triphosphate (ATP) energy level. Consequently, upon integration, GV-(NH4)2S triggered substantial tumor cell killing in vitro and complete 4T1 tumor ablation in vivo, with negligible tumor recurrence and systemic side effects, under the guidance of photoacoustic (PA)/photothermal duplex imaging. This work highlighted the great promise of GVs as a versatile nanocarrier for spatio-temporally controlled and on-demand delivery of gaseous messengers to achieve precision cancer theranostics.

Role of Mitophagy in Myocardial Ischemia/Reperfusion Injury and Chinese Medicine Treatment.

Mitophagy is one of the important targets for the prevention and treatment of myocardial ischemia/reperfusion injury (MIRI). Moderate mitophagy can remove damaged mitochondria, inhibit excessive reactive oxygen species accumulation, and protect mitochondria from damage. However, excessive enhancement of mitophagy greatly reduces adenosine triphosphate production and energy supply for cell survival, and aggravates cell death. How dysfunctional mitochondria are selectively recognized and engulfed is related to the interaction of adaptors on the mitochondrial membrane, which mainly include phosphatase and tensin homolog deleted on chromosome ten (PTEN)-induced kinase 1/Parkin, hypoxia-inducible factor-1 α/Bcl-2 and adenovirus e1b19k Da interacting protein 3, FUN-14 domain containing protein 1 receptor-mediated mitophagy pathway and so on. In this review, the authors briefly summarize the main pathways currently studied on mitophagy and the relationship between mitophagy and MIRI, and incorporate and analyze research data on prevention and treatment of MIRI with Chinese medicine, thereby provide relevant theoretical basis and treatment ideas for clinical prevention of MIRI.

Glucose transporter 1 (GLUT1)-targeting and hypoxia-activated mitochondria-specific chemo-thermal therapy via a glycosylated poly(amido amine)/celastrol (PAMAM/Cel) complex

Mitochondria are appealing targets in cancer therapy for providing a suitable microenvironment and energy supply. Herein, we constructed a glycosylated poly(amido amine)/celastrol (PAMAM/Cel) complex for hypoxia-activated mitochondria-specific drug delivery and chemothermal therapy to inhibit tumor growth and metastasis. The complex was characterized by high photothermal conversion efficiency, hypoxia-sensitive polyethylene glycol (PEG) outer layer detachment, and alkaline-sensitive drug release. The complex showed specific cellular uptake in glucose transporter 1 (GLUT1)-overexpressing tumor cells and mitochondrial accumulation in a hypoxic environment. Combined with near-infrared (NIR) laser irradiation, the complex exhibited higher cytotoxicity, apoptosis induction, and metastasis inhibition rates due to the synergistic chemothermal effect. Similarly, the complex also targeted tumors and accumulated in mitochondria in tumor-bearing nude mice, resulting in superior inhibitory effects on tumor growth and metastasis as well as low systematic toxicity. Further mechanistic studies discovered that the complex impaired the mitochondrial membrane, reduced adenosine triphosphate (ATP) content, and regulated metastasis-related protein expression. Thus, the present study provides a promising nanomedicine for tumor therapy.

The brain-derived neurotrophic factor prompts platelet aggregation and secretion

AbstractBrain-derived neurotrophic factor (BDNF) has both autocrine and paracrine roles in neurons, and its release and signaling mechanisms have been extensively studied in the central nervous system. Large quantities of BDNF have been reported in circulation, essentially stored in platelets with concentrations reaching 100- to 1000-fold those of neurons. Despite this abundance, the function of BDNF in platelet biology has not been explored. At low concentrations, BDNF primed platelets, acting synergistically with classical agonists. At high concentrations, BDNF induced complete biphasic platelet aggregation that in part relied on amplification from secondary mediators. Neurotrophin-4, but not nerve growth factor, and an activating antibody against the canonical BDNF receptor tropomyosin-related kinase B (TrkB) induced similar platelet responses to BDNF, suggesting TrkB could be the mediator. Platelets expressed, both at their surface and in their intracellular compartment, a truncated form of TrkB lacking its tyrosine kinase domain. BDNF-induced platelet aggregation was prevented by inhibitors of Ras-related C3 botulinum toxin substrate 1 (Rac1), protein kinase C, and phosphoinositide 3-kinase. BDNF-stimulated platelets secreted a panel of angiogenic and inflammatory cytokines, which may play a role in maintaining vascular homeostasis. Two families with autism spectrum disorder were found to carry rare missense variants in the BDNF gene. Platelet studies revealed defects in platelet aggregation to low concentrations of collagen, as well as reduced adenosine triphosphate secretion in response to adenosine diphosphate. In summary, circulating BDNF levels appear to regulate platelet activation, aggregation, and secretion through activation of a truncated TrkB receptor and downstream kinase-dependent signaling.

Brief report: The uricase mutation in humans increases our risk for cancer growth

BackgroundRecent studies suggest that fructose, as well as its metabolite, uric acid, have been associated with increased risk for both cancer incidence and growth. Both substances are known to cause oxidative stress to mitochondria and to reduce adenosine triphosphate (ATP) production by blocking aconitase in the Krebs cycle. The uricase mutation that occurred in the Miocene has been reported to increase serum uric acid and to amplify the effects of fructose to stimulate fat accumulation. Here we tested whether the uricase mutation can also stimulate tumor growth.MethodsExperiments were performed in mice in which uricase was inactivated by either knocking out the gene or by inhibiting uricase with oxonic acid. We also studied mice transgenic for uricase. These mice were injected with breast cancer cells and followed for 4 weeks.ResultsThe inhibition or knockout of uricase was associated with a remarkable increase in tumor growth and metastases. In contrast, transgenic uricase mice showed reduced tumor growth.ConclusionA loss of uricase increases the risk for tumor growth. Prior studies have shown that the loss of the mutation facilitated the ability of fructose to increase fat which provided a survival advantage for our ancestors that came close to extinction from starvation in the mid Miocene. Today, however, excessive fructose intake is rampant and increasing our risk not only for obesity and metabolic syndrome, but also cancer. Obesity-associated cancer may be due, in part, to a mutation 15 million years ago that acted as a thrifty gene.

Calotropis gigantea stem bark extract induced apoptosis related to ROS and ATP production in colon cancer cells.

Conventional chemotherapeutic agents for colorectal cancer (CRC) cause systemic side effects and eventually become less efficacious owing to the development of drug resistance in cancer cells. Therefore, new therapeutic regimens have focused on the use of natural products. The anticancer activity of several parts of Calotropis gigantea has been reported; however, the effects of its stem bark extract on inhibition of cancer cell proliferation have not yet been examined. In this study, the anticancer activity of C. gigantea stem bark extract, both alone and in combination with 5-fluorouracil (5-FU), was evaluated. A crude ethanolic extract was prepared from dry, powdered C. gigantea barks using 95% ethanol. This was then partitioned to obtain dichloromethane (CGDCM), ethyl acetate, and water fractions. Quantitative analysis of the constituent secondary metabolites and calotropin was performed. These fractions exhibited cytotoxicity in HCT116 and HT-29 cells, with CGDCM showing the highest potency in both the cell lines. A combination of CGDCM and 5-FU significantly enhanced the cytotoxic effect. Moreover, the resistance of normal fibroblast, HFF-1, cells to this combination demonstrated its safety in normal cells. The combination significantly enhanced apoptosis through the mitochondria-dependent pathway. Additionally, the combination reduced adenosine triphosphate production and increased the production of reactive oxygen species, demonstrating the mechanisms involved in the induction of apoptosis. Our results suggest that CGDCM is a promising anti-cancer agent and may enhance apoptosis induction by 5-FU in the treatment of CRC, while minimizing toxicity toward healthy cells.

Epilepsy in Mitochondrial Diseases-Current State of Knowledge on Aetiology and Treatment.

Mitochondrial diseases are a heterogeneous group of diseases resulting from energy deficit and reduced adenosine triphosphate (ATP) production due to impaired oxidative phosphorylation. The manifestation of mitochondrial disease is usually multi-organ. Epilepsy is one of the most common manifestations of diseases resulting from mitochondrial dysfunction, especially in children. The onset of epilepsy is associated with poor prognosis, while its treatment is very challenging, which further adversely affects the course of these disorders. Fortunately, our knowledge of mitochondrial diseases is still growing, which gives hope for patients to improve their condition in the future. The paper presents the pathophysiology, clinical picture and treatment options for epilepsy in patients with mitochondrial disease.

Antiplatelet Activity of Isorhamnetin via Mitochondrial Regulation.

With the diet, we ingest nutrients capable of modulating platelet function, which plays a crucial role in developing cardiovascular events, one of the leading causes of mortality worldwide. Studies that demonstrate the antiplatelet and antithrombotic potential of bioactive compounds are vital to maintaining good cardiovascular health. In this work, we evaluate the flavonol isorhamnetin’s antiplatelet effect on human platelets, using collagen, thrombin receptor activator peptide 6 (TRAP-6), and phorbol myristate acetate (PMA) as agonists. Isorhamnetin induced a significant inhibition on collagen- and TRAP-6-induced platelet aggregation, with half-maximum inhibitory concentration (IC50) values of 8.1 ± 2.6 and 16.1 ± 11.1 µM, respectively; while it did not show cytotoxic effect. Isorhamnetin reduced adenosine triphosphate levels (ATP) in platelets stimulated by collagen and TRAP-6. We also evidenced that isorhamnetin’s antiplatelet activity was related to the inhibition of mitochondrial function without effect on reactive oxygen species (ROS) levels. Additionally, we investigated isorhamnetin’s effect on thrombus formation in vitro under flow conditions on the damaged vessel wall. In this context, we demonstrate that isorhamnetin at 20 µM induced a significant inhibition on platelet deposition, confirming its antithrombotic effect. Our findings corroborate the antiplatelet and antithrombotic potential of isorhamnetin present in many foods of daily consumption.

Contrasting strategies of hypoxic cardiac performance and metabolism in cichlids and armoured catfish.

The heart of tropical fishes is a particularly useful model system in which to investigate mechanisms of hypoxic tolerance. Here we focus on insights gained from two groups of fishes, cichlids and armoured catfishes. Cichlids respond to hypoxia by entering a sustained hypometabolism with decreased heart performance to match whole animal circulatory needs. Heart rate is decreased along with protein turnover to reduce adenosine triphosphate demand. This occurs despite the inherent capacity for high levels of cardiac power development. Although highly hypoxic tolerant at the whole animal level, the heart of cichlids does not have high constitutive activities of glycolytic enzymes compared to other species. Information is conflicting with respect to changes in glycolytic gene expression and enzyme activity following hypoxic exposure with some studies showing increases and others decreases. In contrast to cichlids, species of armoured catfish, that are routinely exposed to water of low oxygen content, do not display hypoxic bradycardia. Under hypoxia there are early changes in glucose trafficking suggestive of activation of glycolysis before lactate accumulation. Thereafter, heart glycogen is mobilized and lactate accumulates in both heart and blood, in some species to very high levels. Heart performance under hypoxia is enhanced by defense of intracellular pH. A functional sarcoplasmic reticulum and binding of hexokinase to the outer mitochondrial membrane may also play a role in cardioprotection. Maintenance of heart performance under hypoxia may relate to a tradeoff between air breathing via a modified stomach and circulatory demands for digestion.

AFB1-induced mice liver injury involves mitochondrial dysfunction mediated by mitochondrial biogenesis inhibition

Aflatoxin B1 (AFB1) pollutes foodstuffs and feeds, causing a food safety problem and seriously endangering human and animal health. Liver is the principal organ for AFB1 accumulation and biotransformation, during which AFB1 can cause acute and chronic liver damage, however, the specific mechanism is not completely clear. Mitochondria are the primary organelle of cellular bio-oxidation, providing 95% energy for liver to execute its multiple functions. Therefore, we speculated that mitochondrial dysfunction is involved in AFB1-induced liver injury. To verify the hypothesis, a total of eighty healthy male mice were randomly divided into four groups on average, and exposed with 0, 0.375, 0.75 and 1.5 mg/kg body weight AFB1 by intragastric administration for 30 d. The results displayed that AFB1 triggered liver injury accompanied by oxidative stress. AFB1 exposure also damaged mitochondria structure, decreased mitochondrial membrane potential (MMP), as well as increased cytoplasmic cytochrome c (Cyt-c) protein expression, Bax, p53, Caspase-3/9 protein and/or mRNA expression levels and terminal deoxynucleotidyl transferase-mediated 2'-deoxyuridine-5'-triphosphate (dUTP) nick end labeling (TUNEL) staining positive cells in mice liver. Meanwhile, AFB1 exposure elevated pyruvate content, inhibited tricarboxylic acid (TCA) cycle rate-limiting enzymes and electron transport chain (ETC) complexes I-V activities, disturbed ETC complexes I-V subunits mRNA expression levels and reduced adenosine triphosphate (ATP) level in mice liver. These results indicated that AFB1 destroyed mitochondrial structure, activated mitochondrion-dependent apoptosis and induced mitochondrial dysfunction. In addition, AFB1 disrupted mitochondrial biogenesis, presented as the abnormalities of protein and/or gene expression levels of voltage dependent anion channel protein 1 (VDAC1), peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α), nuclear respiratory factor 1 (Nrf1) and mitochondrial transcription factor A (Tfam). This may contribute to hepatic and mitochondrial lesions induced by AFB1. These results provide a new perspective for elucidating the mechanisms of AFB1 hepatotoxicity.

Time-Course Evaluation of Brain Regional Mitochondrial Bioenergetics in a Pre-Clinical Model of Severe Penetrating Traumatic Brain Injury.

Mitochondrial dysfunction is a pivotal target for neuroprotection strategies for traumatic brain injury (TBI). However, comprehensive time-course evaluations of mitochondrial dysfunction are lacking in the pre-clinical penetrating TBI (PTBI) model. The current study was designed to characterize temporal responses of mitochondrial dysfunction from 30 min to 2 weeks post-injury after PTBI. Anesthetized adult male rats were subjected to either PTBI or sham craniectomy (n = 6 animals per group × 7 time points). Animals were euthanized at 30 min, 3 h, 6 h, 24 h, 3 days, 7 days, and 14 days post-PTBI, and mitochondria were isolated from the ipsilateral hemisphere of brain regions near the injury core (i.e., frontal cortex [FC] and striatum [ST]) and a more distant region from the injury core (i.e., hippocampus [HIP]). Mitochondrial bioenergetics parameters were measured in real time using the high-throughput procedures of the Seahorse Flux Analyzer (Agilent Technologies, Santa Clara, CA). The post-injury time course of FC + ST showed a biphasic mitochondrial bioenergetics dysfunction response, indicative of reduced adenosine triphosphate synthesis rate and maximal respiratory capacity after PTBI. An initial phase of energy crisis was detected at 30 min (-42%; p < 0.05 vs. sham), which resolved to baseline levels between 3 and 6 h (non-significant vs. sham). This was followed by a second and more robust phase of bioenergetics dysregulation detected at 24 h that remained unresolved out to 14 days post-injury (-55% to -90%; p < 0.05 vs. sham). In contrast, HIP mitochondria showed a delayed onset of mitochondrial dysfunction at 7 days (-74%; p < 0.05 vs. sham) that remained evident out to 14 days (-51%; p < 0.05 vs. sham) post-PTBI. Collectively, PTBI-induced mitochondrial dysfunction responses were time and region specific, evident differentially at the injury core and distant region of PTBI. The current results provide the basis that mitochondrial dysfunction may be targeted differentially based on region specificity post-PTBI. Even more important, these results suggest that therapeutic interventions targeting mitochondrial dysfunction may require extended dosing regimens to achieve clinical efficacy after TBI.

Mitochondrial dysfunction resulting from the down-regulation of bone morphogenetic protein 5 may cause microtia.

BackgroundBone morphogenetic protein 5 (BMP5) has been identified as one of the important risk factors for microtia; however, the link between them has yet to be clarified. In this study, we aimed to demonstrate the relationship of BMP5 with mitochondrial function and investigate the specific role of mitochondria in regulating microtia development.MethodsBMP5 expression was measured in auricular cartilage tissues from patients with and without microtia. The effects of BMP5 knockdown on cellular function and mitochondrial function were also analyzed in vitro. Changes in genome-wide expression profiles were measured in BMP5-knockdown cells. Finally, the specific impact of BMP5 down-regulation on mitochondrial fat oxidation was analyzed in vitro.ResultsBMP5 expression was down-regulated in the auricular cartilage tissues of microtia patients. BMP5 down-regulation inhibited various cellular functions in vitro, including cell proliferation, mobility, and cytoactivity. The functional integrity of mitochondria was also damaged, accompanied by a decrease in mitochondrial membrane potential, reactive oxygen species (ROS) neutralization, and reduced adenosine triphosphate (ATP) production. Carnitine O-palmitoyltransferase 2 and diacylglycerol acyltransferase 2, two of the key regulators of mitochondrial lipid oxidation, were also found to be decreased by BMP5 down-regulation.ConclusionsDown-regulation of BMP5 affects glycerolipid metabolism and fatty acid degradation, leading to mitochondrial dysfunction, reduced ATP production, and changes in cell function, and ultimately resulting in microtia. This research provides supporting evidence for an important role of BMP5 down-regulation in affecting mitochondrial metabolism in cells, and sheds new light on the mechanisms underlying the pathogenesis of microtia.

Comparative study of rapid ATP bioluminescence assay and conventional plate count method for development of rapid disinfecting activity test.

Antimicrobial activity is tested when developing disinfectants, pharmaceutical products, cosmetics, and many other consumer products. However, the plate count method, the conventional way to count the number of microorganisms, needs several days of culture. Consequently, a means of rapid microbial detection is strongly desired to replace this method. We have already developed a rapid and sensitive microbial adenosine triphosphate (ATP) detection system utilizing ATP bioluminescence, which can quantify microbial ATP within 1 h. To apply this technique to antibacterial activity tests, the ATP method should be proved equal or superior to the conventional method. In this study, we conducted disinfectant activity tests comparing the ATP method and the plate count method, using polyhexamethylene biguanide (PHMB) in different concentrations (0-10 ppm) as a model disinfectant against Staphylococcus aureus and Aspergillus brasiliensis. We found that the log reduction of intracellular ATP had a positive correlation with the log reduction of the plate count. Moreover, the ATP method was able to distinguish different conditions of injured microbial cells that were observed using scanning electron microscopy, whereas colony counting detects only culturable cells. The ATP method is thus a rapid and useful alternative to the conventional method in the field of antimicrobial activity testing.

Platelet mitochondrial function and endogenous coenzyme Q10 levels are reduced in patients after COVID-19.

After an acute treatment for coronavirus disease (COVID-19), some symptoms may persist for several weeks, for example: fatigue, headaches, muscle and joint pain, cough, loss of taste and smell, sleep and memory disturbances, depression. Many viruses manipulate mitochondrial function, but the exact mechanisms of SARS-CoV-2 virus effect remain unclear. We tested the hypothesis that SARS-CoV-2 virus may affect mitochondrial energy production and endogenous biosynthesis of coenzyme Q10 (CoQ10). Ten patients after COVID-19 and 15 healthy individuals were included in the study. Platelets isolated from peripheral blood were used as an accessible source of mitochondria. High-resolution respirometry for the evaluation of platelets mitochondrial function, and HPLC method for CoQ10 determination were used. Oxidative stress was evaluated by TBARS concentration in plasma. Platelet mitochondrial respiratory chain function, oxidative phosphorylation and endogenous CoQ10 level were reduced in the patients after COVID-19. We assume that a reduced concentration of endogenous CoQ10 may partially block electron transfer in the respiratory chain resulting in a reduced adenosine triphosphate (ATP) production in the patients after COVID-19. Targeted mitochondrial therapy with CoQ10 supplementation and spa rehabilitation may improve mitochondrial health and accelerate the recovery of the patients after COVID-19. Platelet mitochondrial function and CoQ10 content may be useful mitochondrial health biomarkers after SARS-CoV-2 infection (Tab. 3, Fig. 3, Ref. 46).

Increasing neuronal glucose uptake attenuates brain aging and promotes life span under dietary restriction in Drosophila.

SummaryBrain neurons play a central role in organismal aging, but there is conflicting evidence about the role of neuronal glucose availability because glucose uptake and metabolism are associated with both aging and extended life span. Here, we analyzed metabolic changes in the brain neurons of Drosophila during aging. Using a genetically encoded fluorescent adenosine triphosphate (ATP) biosensor, we found decreased ATP concentration in the neuronal somata of aged flies, correlated with decreased glucose content, expression of glucose transporter and glycolytic enzymes and mitochondrial quality. The age-associated reduction in ATP concentration did not occur in brain neurons with suppressed glycolysis or enhanced glucose uptake, suggesting these pathways contribute to ATP reductions. Despite age-associated mitochondrial damage, increasing glucose uptake maintained ATP levels, suppressed locomotor deficits, and extended the life span. Increasing neuronal glucose uptake during dietary restriction resulted in the longest life spans, suggesting an additive effect of enhancing glucose availability during a bioenergetic challenge on aging.

Reducing the Impacts of Biofouling in RO Membrane Systems through In Situ Low Fluence Irradiation Employing UVC-LEDs.

Biofouling is a major concern for numerous reverse osmosis membrane systems. UV pretreatment of the feed stream showed promising results but is still not an established technology as it does not maintain a residual effect. By conducting accelerated biofouling experiments in this study, it was investigated whether low fluence UV in situ treatment of the feed using UVC light-emitting diodes (UVC-LEDs) has a lasting effect on the biofilm. The application of UVC-LEDs for biofouling control is a novel hybrid technology that has not been investigated, yet. It could be shown that a low fluence of 2 mJ∙cm−2 delays biofilm formation by more than 15% in lab-scale experiments. In addition, biofilms at the same feed channel pressure drop exhibited a more than 40% reduced hydraulic resistance. The delay is probably linked to the inactivation of cells in the feed stream, modified adsorption properties or an induced cell cycle arrest. The altered hydraulic resistance might be caused by a change in the microbial community, as well as reduced adenosine triphosphate levels per cells, possibly impacting quorum sensing and extracellular polymeric substances production. Due to the observed biofilm attributes, low fluence UV-LED in situ treatment of the feed stream seems to be a promising technology for biofouling control.

Mitochondria-Targeted Polyamidoamine Dendrimer-Curcumin Construct for Hepatocellular Cancer Treatment.

Mitochondrial malfunction plays a crucial role in cancer development and progression. Cancer cells show a substantially higher mitochondrial activity and greater mitochondrial transmembrane potential than normal cells. This concept can be exploited for targeting cytotoxic drugs to the mitochondria of cancer cells using mitochondrial-targeting compounds. In this study, a polyamidoamine dendrimer-based mitochondrial delivery system was prepared for curcumin using triphenylphosphonium ligands to improve the anticancer efficacy of the drug in vitro and in vivo. For the in vitro evaluations, various methods, such as viability assay, confocal microscopy, flow cytometry, reactive oxygen species (ROS), and real-time polymerase chain reaction analyses, were applied. Our findings showed that the targeted-dendrimeric curcumin (TDC) could successfully deliver and colocalize the drug to the mitochondria of the cancer cells, and selectively induce a potent apoptosis and cell cycle arrest at G2/M. Moreover, at a low curcumin dose of less than 25 μM, TDC significantly reduced adenosine triphosphate and glutathione, and increased the ROS level of the isolated rat hepatocyte mitochondria. The in vivo studies on the Hepa1-6 tumor-bearing mice also indicated a significant tumor suppression effect and the highest median survival days (Kaplan-Meier survival estimation and log-rank test) after treatment with the TDC construct compared to the free curcumin and untargeted construct. Besides its targeted nature and safety, the expected improved solubility and stability represent the prepared targeted-dendrimeric construct as an up-and-coming candidate for cancer treatment. The results of this study emphasize the promising route of mitochondrial targeting as a practical approach for cancer therapy, which can be achieved by optimizing the delivery method.

Mortality Among Veterans with a Diagnosis of Pyruvate Kinase (PK) Deficiency: A Real-World Study Using US Veterans Health Administration Data

Background: Pyruvate kinase (PK) deficiency is a rare, inherited disorder caused by autosomal recessive mutations in the PKLR gene, whereby a glycolytic defect causes reduced adenosine triphosphate levels and leads to hemolytic anemia. Patients with PK deficiency can experience serious complications associated with the disease and its treatment, including osteoporosis, pulmonary hypertension, sepsis, iron overload, and liver cirrhosis. The current standard of care for PK deficiency is supportive, including blood transfusions, splenectomy, iron chelation therapy and/or interventions for other disease-related morbidity. There is no approved therapy for this condition. Identifying PK deficiency in real-world data is challenging due to a lack of diagnosis codes and treatments that are specific to PK deficiency. As a result, population-based studies of PK deficiency using claims or electronic health record databases are limited. In addition, data on mortality in this patient population are lacking and limited to a few individual case reports. This study aimed to identify patients with a PK deficiency diagnosis as documented by physicians and to compare their mortality to an age- and gender-matched cohort of individuals without PK deficiency. Methods: Patients with ≥ 1 diagnosis code related to PK deficiency (i.e., anemia due to disorders of glycolytic enzymes [International Classification of Diseases, Tenth Revision, Clinical Modification (ICD-10-CM) D55.2], other hemolytic anemias due to enzyme deficiency [ICD-9-CM 282.3], or unspecified hereditary hemolytic anemia [ICD-9-CM 282.9, ICD-10-CM D58.9]) between January 1995 and July 2019 were selected from the US Veterans Health Administration (VHA) database. To be considered for inclusion, physicians' notes were required to contain the words "pyruvate", "kinase", and "deficiency." A manual review of these physicians' notes was performed to identify patients with a physician-documented diagnosis of PK deficiency (PK deficiency cohort). The index date for the PK deficiency cohort was defined as the date of the first medical record with a diagnosis code related to PK deficiency. Each patient in the PK deficiency cohort was matched 1:5 by age at index, sex, and index year (± 1 year) to patients from the general VHA population with no diagnosis codes related to PK deficiency (non-PK deficiency cohort). The index date for the non-PK deficiency cohort was defined as a random visit date during their match's index year. Survival time from the index date was compared between the PK deficiency cohort and their non-PK deficiency cohort matches using a univariate Cox proportional hazards model with robust standard error estimation. Results: A total of 18 patients met inclusion criteria for the PK deficiency cohort and were matched to 90 individuals in the non-PK deficiency cohort. Baseline characteristics for both cohorts are shown in the Table. For both cohorts, the mean age at index was 57 years and 94% of patients were male; 83-85% were white and the mean Charlson Comorbidity Index score was 0.4-0.5 (no significant differences between cohorts). Imbalances remained between the two cohorts with regard to region and body mass index. The median follow-up was 6.0 years for the PK deficiency cohort and 8.0 years for the non-PK deficiency cohort. Over the follow-up period, there were 9 (50%) observed deaths in the PK deficiency cohort and 28 (31%) observed deaths in the non-PK deficiency cohort. The median time until death was 10.9 years for the PK deficiency cohort and 17.1 years for the non-PK deficiency cohort; the Kaplan-Meier curves for both cohorts are shown in the Figure. Patients in the non-PK deficiency cohort had a significantly longer time to death than the PK deficiency cohort (hazard ratio: 2.3; p = 0.0306); 10 years after index, 42% of patients in the PK deficiency cohort had died compared with 28% of those in the non-PK deficiency cohort. Conclusions: The results of this study suggest that patients with PK deficiency may be at an increased risk of mortality. Further research to understand cause of death in this population is warranted, as is the replication of this study using larger sample sizes and other real-world data sources that better represent females and the pediatric and adolescent PK deficiency age groups. Disclosures Zagadailov: Agios Pharmaceuticals: Current Employment, Current equity holder in publicly-traded company. Boscoe:Agios Pharmaceuticals: Current Employment, Current equity holder in private company. Garcia-Horton:Agios Pharmaceuticals: Consultancy; Analysis Group, Inc.: Current Employment. Shi:Agios Pharmaceuticals: Consultancy; Analysis Group, Inc.: Current Employment. Liu:Analysis Group, Inc.: Consultancy. Shi:Analysis Group, Inc.: Consultancy. Macaulay:Agios Pharmaceuticals: Consultancy; Analysis Group, Inc.: Current Employment.