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Biological Correlates of Microwave
Published in Jitendra Behari, Radio Frequency and Microwave Effects on Biological Tissues, 2019
Cell communicates with each other and responds to extracellular stimuli through cell signaling (signal transduction) is a well-established biological mechanism. Signal transduction is a process enabling information to be transmitted from the outside of a cell to various functional elements inside the cell. Signal transduction is triggered by extracellular signals (hormones, growth factors, cytokines and neurotransmitters). Signals sent to the transcription machinery are responsible for expression of certain genes that are normally transmitted to the cell nucleus by a class of proteins called transcription factors. Because ROS act as oxidants by nature, they influence the redox status and may, according to their concentration, cause either cell proliferation, or cause growth arrest or cell death or even necrosis (Sharma et al. 1999). The effects of ROS on cell proliferation occur exclusively at low or transient concentration of radicals. Low concentration of superoxide radical and hydrogen peroxide in fact stimulate proliferation and enhanced survival in a variety of cell types. ROS can thus play a very important physiological role as secondary messengers.
Preformulation of New Biological Entities
Published in Sandeep Nema, John D. Ludwig, Parenteral Medications, 2019
Riccardo Torosantucci, Vasco Filipe, Jonathan Kingsbury, Atul Saluja, Yatin Gokarn
Cytokines are small hormone proteins that act in cell signaling pathways, most commonly in the activation of immune system components such as lymphocytes and macrophages. Interferons are potent glycoprotein cytokines with antiviral properties and can suppress uncontrolled cell proliferation. They have been used in the treatment of multiple sclerosis, immunological cancers, and hepatitis. Biotherapeutic interferons include interferon-α (e.g., Roferon-A®, Intron-A®, and Alferon-N®), interferon-β (e.g., Avonex®, Betaseron®, and Extavia®), and interferon-γ (e.g., Actimmune®). Similar to the interferons, the interleukins function as biochemical signals during immune response, with either stimulatory or inhibitory activities. For example, interleukin-1 (IL-1) controls pro-inflammatory reactions in response to tissue injury by pathogen- or danger-associated molecular patterns. Therefore, IL-1 receptor antagonists, such as anakinra (Kineret®), can be used in the treatment of inflammatory conditions such as rheumatoid arthritis. Recombinant interleukin-2 (IL-2), aldesleukin (Proleukin®), stimulates T cells and is used in the treatment of metastatic renal cell carcinoma and melanoma.
Terpenoids: The Biological Key Molecules
Published in Dijendra Nath Roy, Terpenoids Against Human Diseases, 2019
Moumita Majumdar, Dijendra Nath Roy
Cellular communication is accomplished through the interaction of extracellular and intracellular messengers. Ligands are commonly recognised as extracellular chemical signals which activate or regulate signalling via binding with cell surface receptors and conformational changes, whereas inside the cell, local messengers (neurotransmitters and hormones from neighbouring cells) are major components of intracellular networks. In this chapter, the role of terpenoids as messenger molecules will be discussed in detail. Terpenoids, isoprenoids and their derivatives play important roles in signal transduction both plant and animal cells. Here, the topic of interest for discussion is the effect of terpenoids at the cellular level in the animal kingdom. Cells of an organism use techniques for communicating with their microenvironment and for keeping this coordination in proper form in the cells: This biological process is designated as cell signalling. Impairment in the consecutive steps of signalling pathways is the principal cause of diseases like cancer, diabetes and autoimmunity (Solinas et al. 2007; Wang et al. 2012a; Vlahopoulos et al. 2015). In the animal cell, a large number of cell-signalling pathways exist for the regulation of cellular metabolism resources, developmental signalling, autophagy, motor signalling cascade, apoptotic resources, MAPK pathways, tyrosine kinase signalling, immunity and inflammation and so on. Being the largest group of natural products, terpenoids have a potential impact on cell signalling in living organisms, and they have specific significant roles in these pathways.
Genetic and substrate-level modulation of Bacillus subtilis physiology for enhanced extracellular human interferon gamma production
Published in Preparative Biochemistry and Biotechnology, 2018
Nitin Kumar, Rajat Pandey, Ashish Anand Prabhu, Veeranki Venkata Dasu
Cell signaling molecules such as cytokines play a vital role in cell to cell communications, immune responses and stimulate the movement of cells toward sites of inflammation, infection, and trauma. Human interferon gamma (hIFNG) is a type II interferon, which possess a broad range of biological activity and finds its therapeutic applications in the treatment of chronic granulomatous, cancer, tuberculosis, HIV, and malignant osteoporosis.[123] Till date the industrial production of hIFNG was performed in Escherichia coli expression platform, which ultimately resulted in inclusion body formation.[4567] Only two reports claim to produce soluble periplasmic hIFNG in E. coli, and moreover, the soluble production levels are very less even after genetic and physiological engineering of the host.[8,9] Both the Sec and Tat signal peptide-dependent protein translocation machinery could not alleviate the inclusion body problem. However, cultivation temperature at 20°C emerged as a significant physiological growth parameter, which enhanced the hIFNG fraction in the periplasmic space, but the extracellular soluble hIFNG production could not be achieved,[9] which necessitates the search for an alternative expression platform, as purification and refolding of hIFNG from inclusion bodies and the periplasmic space increase the downstream processing cost and also require stringent quality control certificates to ensure the absence of nucleic acids and endotoxins from E. coli.[4] Even the higher level eukaryotic expression platform such as Pichia pastoris has been very recently reported for inconsistent and nonreproducible production of hIFNG, which is commercially undesirable.[101112] These observations leave the search for an alternative host an interesting area to explore for extracellular, soluble, safe, and cheaper production of hIFNG.