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Recent Developments in Therapies and Strategies Against COVID-19
Published in Hanadi Talal Ahmedah, Muhammad Riaz, Sagheer Ahmed, Marius Alexandru Moga, The Covid-19 Pandemic, 2023
Misbah Hameed, M. Zia-Ul-Haq, Marius Moga
Lopinavir is a protease inhibitor and is prepared from structurally similar ritonavir antiretroviral agents. Aspartic protease is essential for the cleavage of proteins from precursor polypeptide strand of virus, which is needed for structural and functional proteins. The inhibition of protease results in immature and non-effective virions [20]. Lopinavir is a selective inhibitor of the HIV type 1 (HIV-1), which is required for mature infective virus production. The drug blocks infectivity by blocking the maturation of HIV-1. Lopinavir is a highly potent. These two drugs are available as formulation because when co-administered, ritonavir at low doses improves the pharmacokinetic profile and the activity of lopinavir against HIV-1 protease [21].
Biodiscovery of Marine Microbial Enzymes in Indonesia
Published in Se-Kwon Kim, Marine Biochemistry, 2023
Ekowati Chasanah, Pujo Yuwono, Dewi Seswita Zilda, Siswa Setyahadi
Proteolytic enzymes have been used as meat tenderizers, and under controlled conditions and the right concentration of the proteolytic enzyme, the toughness of the meat will be reduced and the eating quality of meat enhanced (Madhusankha & Thilakarathna, 2021). Protease enzymes also have an important role in the dairy industry, namely, cheese, yogurt, kefir, and other so-called fermented dairy products. It was reported that some LAB (lactic acid bacteria) produce microbial proteases that may replace chymosin in cheese production; bakeries, that is, in the production of bread and pastries; brewing; food additives, such as protein hydrolyzates; and the feed industry (Kieliszek et al., 2021). Aspartic proteases have been reported to be applied in the food and beverage industries, such as in cheese making for the milk-clotting process, in fruit juices and alcoholic drink products to make clear of for hydrolyzing protein turbidity complex, and in the bread industry by modifying wheat gluten (Mamo & Assefa, 2018). The biodiscovery of protease to support the food industry to improve meat quality or as a tenderizer, and other applications are widely open along with the development of the food industry for both local and global needs.
Antiviral Agents and Rational Drug Design
Published in Nathan Keighley, Miraculous Medicines and the Chemistry of Drug Design, 2020
The HIV protease enzyme is an aspartyl protease, which contains an aspartic acid residue in the active site, which is crucial for the catalytic cleavage of peptide bonds. The enzyme is a relatively small protein that can be readily made by synthetic techniques or by cloning and expression in rapidly dividing cells, then isolated and purified in large quantities. Crystallisation of HIV protease is relatively straightforward, hence this enzyme is an ideal target for rational structure-based drug design. From x-ray crystallographic studies, novel inhibiters can be developed to produce promising lead compounds.
Neuroprotective effect of quercetin through targeting key genes involved in aluminum chloride induced Alzheimer’s disease in rats
Published in Egyptian Journal of Basic and Applied Sciences, 2023
Hala A Elreedy, Asmaa M. Elfiky, Asmaa Ahmed Mahmoud, Khadiga S. Ibrahim, Mohamed A Ghazy
Gamma-secretase is an intramembrane aspartyl protease which engaged in Alzheimer’s disease through the proteolysis of APP. Thus, gamma-secretase creates the pathogenic Aβ 1–42 peptide that causes amyloid plaques [43,44]. A protein called Presenilin I (PSEN1) belongs to the aspartic protease family and is involved in the control of intramembrane proteolysis [8]. PSEN1 was believed to be a central, catalytic moiety of the gamma-secretase complex. PSEN1 was reported to be capable of cleaving substrates in the absence of Nicastrin (NCT), APH1 and presenilin enhancer-2 (PEN-2) in an activity assay performed in the liposomes [45]. Therefore, PSEN1 is a candidate target gene in drug design against AD. In the current research, we evaluated the levels of PSEN1 and APH1, two different components of gamma-secretase, in the hippocampus of rat brains. Both PSEN1 and APH1 levels were elevated in the AlCl3-induced AD group in comparison with the normal group. Meanwhile, PSEN1 gene expression level was significantly decreased in co-administration of AlCl3 with Q 50 mg kg-1 to AlCl3-induced AD rat. Suggesting that polyphenols could act as an inhibitor of PSEN1, a study by Lakey-Beitia and Berrocal [46] intended that polyphenols could occupy the active site of gamma-secretase (displacing the water molecule needed for catalysis by the enzyme), would inactivate the enzyme and decrease Aβ formation. On the other hand, Q at 50 mg kg-1 to AlCl3 -induced AD rats showed no significant effect on APH1gene expression compared to AlCl3 group.
Paeonol assists fluconazole and amphotericin B to inhibit virulence factors and pathogenicity of Candida albicans
Published in Biofouling, 2021
Min Pan, Qirui Wang, Ting Cheng, Daqiang Wu, Tianming Wang, Guiming Yan, Jing Shao
The assay for secreted aspartic protease (SAP) was performed as described previously with minor modifications (Srivastava et al. 2018). An aliquot of C. albicans (1×106 cells ml−1) was co-incubated for 3-5days at 37°C with the drugs alone or in combination at their synergistic concentrations in a medium containing 2% dextrose, 0.1% KH2PO4, 0.05% MgSO4, 2% agar, and 1% BSA. A fungal culture without the drug was used as the control. The effect of the drugs on SAP secretion was analyzed in terms of the PZ value calculated as: diameter of the colony/diameter of the precipitation circle + the diameter of the colony (Price et al. 1982). As used for phospholipase (PL) (Khan et al. 2014), the fungal inoculum and the drugs were co-cultured in a media comprising 1% peptone, 3% glucose, 0.055% CaCl2, 5.73% NaCl, and 10% sterile egg yolk. The remnant experimental conditions for PL evaluation were similar to those described for the SAP analyses.
Aloe vera and Honey Solution and Their Ethanolic Extraction Solution Could Act on Metastasis-Regulating Processes in Walker 256 Tumor Tissues In Vivo?
Published in Nutrition and Cancer, 2021
Rebeka Tomasin, Aislan Cristina Rheder Fagundes Pascoal, Marcos José Salvador, Maria Cristina Cintra Gomes-Marcondes
The aspartic protease cathepsin-D is traditionally located inside lysosomes, where it is involved in the acid digestion of proteins and peptides (8). During cancer progression, especially in solid tumors, cathepsin-D is commonly overexpressed and secreted by both cancer and stromal cells; it is believed to promote matrix remodeling, mitosis, angiogenesis, and metastasis (7, 8). Indeed, it has been extensively reported that high levels of cathepsin-D are linked to the occurrence of metastasis and more unsatisfactory outcome in cancer patients, and these effects are believed to be due to the proangiogenic role of cathepsin-D in solid tumors (9, 30). Moreover, several studies have shown that lower levels of cathepsin-D lead to less migration and invasion of several cancer cell lines in vitro, as well as a reduction in metastatic burden in animal models (31). Thus, the observed trend of a decrease in cathepsin-D activity in tumor samples from treated rats may be linked to reduced aggressiveness of these tumors; several independent clinical studies have shown that the cathepsin-D level of primary tumors is an independent prognostic parameter that is correlated with the incidence of metastasis and shorter survival times (9, 32–35).