What do nucleoside analogues do?
The nucleoside analogues resemble naturally occurring nucleosides and act by causing termination of the nascent DNA chain. They are believed to inhibit viral replication by several mechanisms, either by competitive inhibition of the viral polymerase or by DNA chain termination.
Is 5 fluorouracil a nucleoside analogue?
Nucleoside analogues like cytarabine (ara-C), 5-fluorouracil (5-FU) and gemcitabine (dF-dC) are characterised by low oral bioavailability and high first-pass effects in the liver [230,231].
Can nucleotides be used as drugs?
Nucleoside and nucleotide analogues can be used in therapeutic drugs, include a range of antiviral products used to prevent viral replication in infected cells.
How do nucleoside analogues work as antiviral drugs?
Nucleoside analogs are synthetic, chemically modified nucleosides that mimic their physiological counterparts (endogenous nucleosides) and block cellular division or viral replication by impairment DNA/RNA synthesis or by inhibition of cellular or viral enzymes involved in nucleoside/tide metabolism (Figure 1).
Is Remdesivir a nucleoside analog?
Remdesivir is a nucleoside analog, one of the oldest classes of antiviral drugs. It works by blocking the RNA polymerase that coronaviruses and related RNA viruses need to replicate their genomes and proliferate in the host body.
Which is a pyrimidine analogue?
Pyrimidine analogs include 5-fluorouracil, cytosine arabinoside, 5-azacytidine, and gemcitabine.
Is 5-fluorouracil an antineoplastic drug?
Fluorouracil is an anti-cancer (“antineoplastic” or “cytotoxic”) chemotherapy drug.
How do nucleotide analogues work as antiviral drugs?
Antiviral nucleotides are nucleotide analogs that repress the viral reproduction by interfering with several key mechanisms of viral nucleic acid replication. They compete with natural dNTP/NTP substrates for the incorporation into the nascent viral nucleic acid thereby leading to chain termination or mutagenesis (Tab.
What are guanine analogues?
Drugs that closely resemble GUANINE and that are taken up by viruses or neoplastic cells to their disadvantage. Examples are famciclovir (Famvir) used to treat herpes zoster and tioguanine (Lanvis) used to treat acute leukaemias.
What is the target of remdesivir?
Researchers have demonstrated how the drug known as remdesivir works, presenting the viral RNA polymerase of coronaviruses as a target for these conditions.
Which is an example of a nucleoside analogue?
Nucleoside analogues and nucleobases are a pharmacologically diverse family, which includes cytotoxic compounds, antiviral agents, and immunosuppressive molecules. The anticancer nucleosides include several analogues of physiological pyrimidine and purine nucleosides and nucleobases. The two primary purine analogues are cladribine and fludarabine.
Why are nucleoside analogues important in cancer treatment?
The growing importance of nucleoside analogues as cytotoxic agents has stemmed both from the development of newer compounds with broad applicability to common cancers and from an understanding of their mechanisms of action, enabling pharmacological intervention to potentiate the antitumour effects of these compounds.
Are there any analogues of pyrimidine or nucleosides?
The anticancer nucleosides include several analogues of physiological pyrimidine and purine nucleosides and nucleobases. The two primary purine analogues are cladribine and fludarabine. These drugs have mostly been used in the treatment of low-grade malignant disorders of the blood.
How are deoxyadenosine analogs used in cancer treatment?
Deoxyadenosine analogs induce programmed cell death in chronic lymphocytic leukemia cells by damaging the DNA and by directly affecting the mitochondria. Fludarabine and cladribine also alter gene transcription resulting in depletion of proteins required for cell survival.