Current Drug Targets - Volume 23, Issue 8, 2022

Novel coronavirus, SARS-CoV-2, is advancing at a staggering pace to devastate the health care system and foster concerns over public health. In contrast to the past outbreaks, coronaviruses are not clinging themselves as a strict respiratory virus. Rather, becoming a multifaceted virus, it affects multiple organs by interrupting a number of metabolic pathways leading to significant rates of morbidity and mortality. Following infection, they rigorously reprogram multiple metabolic pathways of glucose, lipid, protein, nucleic acid, and their metabolites to extract adequate energy and carbon skeletons required for their existence and further molecular constructions inside a host cell. Although the mechanism of these alterations is yet to be known, the impact of these reprogramming is reflected in the hyperinflammatory responses, so called cytokine storm and the hindrance of the host immune defence system. The metabolic reprogramming during SARSCoV- 2 infection needs to be considered while devising therapeutic strategies to combat the disease and its further complication. The inhibitors of cholesterol and phospholipids synthesis and cell membrane lipid raft of the host cell can, to a great extent, control the viral load and further infection. Depletion of energy sources by inhibiting the activation of glycolytic and hexosamine biosynthetic pathways can also augment antiviral therapy. The cross talk between these pathways also necessitates the inhibition of amino acid catabolism and tryptophan metabolism. A combinatorial strategy that can address the cross talks between the metabolic pathways might be more effective than a single approach, and the infection stage and timing of therapy will also influence the effectiveness of the antiviral approach. We herein focus on the different metabolic alterations during the course of virus infection that help exploit the cellular machinery and devise a therapeutic strategy that promotes resistance to viral infection and can augment body’s antivirulence mechanisms. This review may cast light on the possibilities of targeting altered metabolic pathways to defend against virus infection in a new perspective.

Background: Human papillomavirus (HPV), one of the most frequently transmitted viruses, causes several malignancies, including cervical cancer. Aim: Owing to its unique pathogenicity, the HPV virus can persist in the host organism for a longer duration than other viruses to complete its lifecycle. During its association with the host, HPV causes various pathological conditions affecting the immune system by evading the host's immune mechanisms, thereby leading to the progression of various diseases, including cancer. Method: To date, ~ 150 serotypes have been identified, and certain high-risk HPV types are known to be associated with genital warts and cervical cancer. As of now, two prophylactic vaccines are in use for the treatment of HPV infection; however, no effective antiviral drug is available for HPVassociated disease/infections. Numerous clinical and laboratory studies have been conducted to formulate an effective and specific vaccine against HPV infections and associated diseases. Result: As the immunological basis of HPV infection and associated disease progress persist indistinctly, deeper insights into immune evasion mechanism and molecular biology of disease would aid in developing an effective vaccine. Conclusion: Thus, this systematic review focuses on the immunological aspects of HPV-associated cervical cancer by uncovering immune evasion strategies adapted by HPV.

The unprecedented pandemic of COVID-19 caused by the novel strain of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) engulfs millions of death worldwide. It has directly hit the socio-economic status of the affected countries. There are more than 219 countries badly affected by the COVID-19. There are no particular small molecule inhibitors to combat the dreadful virus. Many antivirals, antimalarials, antiparasitic, antibacterials, immunosuppressive antiinflammatory, and immune stimulatory agents have been repurposed for the treatment of COVID-19. But the exact mechanism of action of these drugs towards COVID-19 targets has not been experimented with yet. Under the effect of chemotherapeutics, the virus may change its genetic material and produces various strains, which are the main reasons behind the dreadful attack of COVID-19. The nuclear genetic components are composed of main protease and RNA-dependent RNA polymerase (RdRp) which are responsible for producing nascent virion and viral replication in the host cells. To explore the biochemical mechanisms of various small molecule inhibitors, structure-based drug design can be attempted utilizing NMR crystallography. The process identifies and validates the target protein involved in the disease pathogenesis by the binding of a chemical ligand at a well-defined pocket on the protein surface. In this way, the mode of binding of the ligands inside the target cavity can be predicted for the design of potent SARS-CoV-2 inhibitors.

Coronaviruses have been receiving continuous attention worldwide as they have caused a serious threat to global public health. This group of viruses is named so as they exhibit characteristic crown-like spikes on their protein coat. SARS-CoV-2, a type of coronavirus that emerged in 2019, causes severe infection in the lower respiratory tract of humans and is often fatal in immunocompromised individuals. No medications have been approved so far for the direct treatment of SARS-CoV-2 infection, and the currently available treatment options rely on relieving the symptoms. The medicinal plants occurring in nature serve as a rich source of active ingredients that could be utilized for developing pharmacopeial and non-pharmacopeial/synthetic drugs with antiviral properties. Compounds obtained from certain plants have been used for directly and selectively inhibiting different coronaviruses, including SARS-CoV, MERS-CoV, and SARS-CoV-2. The present review discusses the potential natural inhibitors against the highly pathogenic human coronaviruses, with a systematic elaboration on the possible mechanisms of action of these natural compounds while acting in the different stages of the life cycle of coronaviruses. Moreover, through a comprehensive exploration of the existing literature in this regard, the importance of such compounds in the research and development of effective and safe antiviral agents is discussed. We focused on the mechanism of action of several natural compounds along with their target of action. In addition, the immunomodulatory effects of these active components in the context of human health are elucidated. Finally, it is suggested that the use of traditional medicinal plants is a novel and feasible remedial strategy against human coronaviruses.

Recent studies have shed light on the role of epigenetic marks in certain diseases like cancer, type II diabetes mellitus (T2DM), obesity, and cardiovascular dysfunction, to name a few. Epigenetic marks like DNA methylation and histone acetylation are randomly altered in the disease state. It has been seen that methylation of DNA and histones can result in down-regulation of gene expression, whereas histone acetylation, ubiquitination, and phosphorylation are linked to enhanced expression of genes. How can we precisely target such epigenetic aberrations to prevent the advent of diseases? The answer lies in the amalgamation of the efficient genome editing technique, CRISPR, with certain effector molecules that can alter the status of epigenetic marks as well as employ certain transcriptional activators or repressors. In this review, we have discussed the rationale of epigenetic editing as a therapeutic strategy and how CRISPR-Cas9 technology coupled with epigenetic effector tags can efficiently edit epigenetic targets. In the later part, we have discussed how certain epigenetic effectors are tagged with dCas9 to elicit epigenetic changes in cancer. Increased interest in exploring the epigenetic background of cancer and non-communicable diseases like type II diabetes mellitus and obesity accompanied with technological breakthroughs has made it possible to perform large-scale epigenome studies.