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Polyphenol Nanoformulations for Cancer Therapy: Role of Milk Components
Published in Lohith Kumar Dasarahally-Huligowda, Megh R. Goyal, Hafiz Ansar Rasul Suleria, Nanotechnology Applications in Dairy Science, 2019
Naphthoquinones are most important and generally distributed group. It has exhibited wide range of biological responses including anti-inflammatory, antiviral, apoptosis, antiplatelet, and so on. Anticancer activity of naphthoquinones has attracted several investigations to formulate a novel drug delivery system. Plumbagin-nanosilver induced apoptotic cell death in human skin cancer cells (HaCaT, A431) by enhancing free radicals. It also increased pyruvate kinase activity possibly indicating augmented metabolism and catalysis of pyruvate and adenosine triphosphate (ATP) synthesis during glycolysis.10,39
Metabolism
Published in Markus W. Covert, Fundamentals of Systems Biology, 2017
Let’s look at one of the reactions in more detail to obtain a sense of its components (Figure 9.2). First, we see the molecular reactants and products: phosphoenolpyruvate (PEP), ADP (adenosine diphosphate), and a hydrogen ion react to form pyruvate and ATP. This reaction requires the catalyzing power of the enzyme pyruvate kinase. Two pyruvate kinase genes are encoded in the E. coli genome, and the functional protein is built of four of either of these gene products. When an enzyme and the reactants are present in the cell, a chemical reaction can proceed (Figure 9.2).
Cell Physiology
Published in Wei-Shou Hu, Cell Culture Bioprocess Engineering, 2020
The enzyme catalyzing the penultimate step of glycolysis, pyruvate kinase, has three isozymes in mammalian systems. The muscle isozyme is expressed as either of two splice variants, M1 or M2. Both muscle isoforms of PK are activated by phosphoenolpyruvate, but only PKM2 is also activated by F16BP. The M1 isoform is mostly expressed in adult tissues, whereas the M2 isoform is expressed in rapidly growing tissues, such as fetal and tumor tissues, and is also thought to be a critical player in the transformation leading to cancer.
The emergence of nanoporous materials in lung cancer therapy
Published in Science and Technology of Advanced Materials, 2022
Deepika Radhakrishnan, Shan Mohanan, Goeun Choi, Jin-Ho Choy, Steffi Tiburcius, Hoang Trung Trinh, Shankar Bolan, Nikki Verrills, Pradeep Tanwar, Ajay Karakoti, Ajayan Vinu
pSi is mostly given via the systemic administration and the detailed investigations of pSi as an injectable nano vector either in the form of suspension or powder are rare. The potential application of pSi for molecular targeting has also been explored in various ways through systemic administration. The specific synthetic small interfering RNA (siRNA) which targets (M2 isoform of pyruvate kinase, PKM2) the glycolytic pathway of lung cancer cells was loaded on the surface of the pSi. Loading the siRNA into the pSi reduces the drawbacks associated with direct siRNA delivery, like sensitivity to nuclease degradation and reduced permeation in cells due to its negative charge. Loading of siRNA on the surface of the pSi was achieved after the PEGylation of the surface by electrostatic adsorption. 95% of the loaded siRNA was released within 30 minutes of the administration, indicating a burst release profile (Figure 5B) that could be reduced by PEGylation [223]. Promising results on albumin coated pSi for the drug delivery of paclitaxel also substantiate the use of pSi as a drug delivery carrier in lung cancers [224]. It was claimed that the albumin coating increased the diffusion resistance and decreased the dissolution rate of pSi.
Adenosine triphosphate (ATP) bioluminescence-based strategies for monitoring atmospheric bioaerosols
Published in Journal of the Air & Waste Management Association, 2022
Yueqi Zhang, Bing Liu, Zhaoyang Tong
The use of adenylate kinase (ADK) and pyruvate kinase for ATP amplification has the potential to detect very low levels of ATP without the use of photon detectors. Lee et al. (2017) designed ATP amplification using (i) ADK as the first enzyme that converts AMP+ATP to two ADP molecules, and (ii) polyP kinase (PPK) as the second enzyme that converts ADP to ATP using polyP. In this reaction, excess AMP and polyP are added to the reaction mixture, which drives the ADK and PPK equilibriums to ADP and ATP formation, respectively. The amplified ATP is subjected to bioluminescence detection in a firefly luciferase reaction. The sensitivity of this method to ATP was about 10,000 times that of the bioluminescence method without ATP amplification. The ATP is amplified before the bioluminescence detection, and the luminescence amount can be improved without signal integration, thereby greatly improving the sensitivity of the bioluminescence detection to ATP.
Effects of pyruvate decarboxylase (pdc1, pdc5) gene knockout on the production of metabolites in two haploid Saccharomyces cerevisiae strains
Published in Preparative Biochemistry & Biotechnology, 2022
Wen Zhang, Jie Kang, Changli Wang, Wenxiang Ping, Jingping Ge
The PDC enzyme activity of S. cerevisiae H14-02 (0.39 ± 0.05 U/mg) and S. cerevisiae H5-02 (0.37 ± 0.04 U/mg) was significantly lower than that of S. cerevisiae H14 (0.66 ± 0.01 U/mg) and S. cerevisiae H5 (0.65 ± 0.01 U/mg). Enzyme activity decreased by 40.91% and 43.08%, respectively. The pdc1pdc5 gene knockout affected but did not block the activity of the PDC enzyme. In addition, the enzyme activity of pyruvate kinase in S. cerevisiae H14-02 and S. cerevisiae H5-02 increased by 53.17% and 66.33%, respectively, compared to that in the parent strains. The enzyme activity of ethanol dehydrogenase in S. cerevisiae H14-02 and S. cerevisiae H5-02 decreased by 47.92% and 47.27%, respectively, compared to that in the parent strains. α-Acetolactate synthase is the first key enzyme in the synthesis of 2,3-BD and increased by 45.33% and 37.84% in H14-02 and H5-02, respectively, when compared to that in the parent strains. The enzyme activity of 2,3-butanediol dehydrogenase in S. cerevisiae H14-02 and S. cerevisiae H5-02 increased by 43.55% and 44.78%, respectively, compared to that in the H14 and H5 parent strains (Figure 3 and Table S3). The enzyme activity results showed that while the double mutants inhibited the expression of PDC, they also affected the activity of pyruvate kinase in the upstream pathway and the activity of ethanol dehydrogenase, α-acetolactate synthase and 2,3-BD dehydrogenase in the downstream pathway.