scholarly journals Inhibition of SARS-CoV-2 in Vero cell cultures by peptide-conjugated morpholino oligomers

Author(s):  
Kyle Rosenke ◽  
Shanna Leventhal ◽  
Hong M Moulton ◽  
Susan Hatlevig ◽  
David Hawman ◽  
...  

Abstract Background As the causative agent of COVID-19, SARS-CoV-2 is a pathogen of immense importance to global public health. Development of innovative direct-acting antiviral agents is sorely needed to address this virus. Peptide-conjugated morpholino oligomers (PPMO) are antisense compounds composed of a phosphorodiamidate morpholino oligomer covalently conjugated to a cell-penetrating peptide. PPMO require no delivery assistance to enter cells and are able to reduce expression of targeted RNA through sequence-specific steric blocking. Methods Five PPMO designed against sequences of genomic RNA in the SARS-CoV-2 5′-untranslated region and a negative control PPMO of random sequence were synthesized. Each PPMO was evaluated for its effect on the viability of uninfected cells and its inhibitory effect on the replication of SARS-CoV-2 in Vero-E6 cell cultures. Cell viability was evaluated with an ATP-based method using a 48 h PPMO treatment time. Viral growth was measured with quantitative RT–PCR and TCID50 infectivity assays from experiments where cells received a 5 h PPMO treatment time. Results PPMO designed to base-pair with sequence in the 5′ terminal region or the leader transcription regulatory sequence region of SARS-CoV-2 genomic RNA were highly efficacious, reducing viral titres by up to 4–6 log10 in cell cultures at 48–72 h post-infection, in a non-toxic and dose-responsive manner. Conclusions The data indicate that PPMO have the ability to potently and specifically suppress SARS-CoV-2 growth and are promising candidates for further preclinical development.

2020 ◽  
Author(s):  
Kyle Rosenke ◽  
Shanna Leventhal ◽  
Hong M. Moulton ◽  
Susan Hatlevig ◽  
David Hawman ◽  
...  

SynopsisBackgroundSARS-CoV-2 is the causative agent of COVID-19 and a pathogen of immense global public health importance. Development of innovative direct-acting antiviral agents is sorely needed to address this virus. Peptide-conjugated morpholino oligomers (PPMO) are antisense agents composed of a phosphordiamidate morpholino oligomer covalently conjugated to a cell-penetrating peptide. PPMO require no delivery assistance to enter cells and are able to reduce expression of targeted RNA through sequence-specific steric blocking.Objectives and MethodsFive PPMO designed against sequences of genomic RNA in the SARS-CoV-2 5’-untranslated region and a negative control PPMO of random sequence were synthesized. Each PPMO was evaluated for its effect on the viability of uninfected cells and its inhibitory effect on the replication of SARS-CoV-2 in Vero-E6 cell cultures. Cell viability was evaluated with an ATP-based method and viral growth was measured with quantitative RT-PCR and TCID50 infectivity assays.ResultsPPMO designed to base-pair with sequence in the 5’-terminal region or the leader transcription regulatory sequence-region of SARS-CoV-2 genomic RNA were highly efficacious, reducing viral titers by up to 4-6 log10 in cell cultures at 48-72 hours post-infection, in a non-toxic and dose-responsive manner.ConclusionThe data indicate that PPMO have the ability to potently and specifically suppress SARS-CoV-2 growth and are promising candidates for further pre-clinical development.


2020 ◽  
Vol 11 (SPL1) ◽  
pp. 977-982
Author(s):  
Mohamed J. Saadh ◽  
Bashar Haj Rashid M ◽  
Roa’a Matar ◽  
Sajeda Riyad Aldibs ◽  
Hala Sbaih ◽  
...  

SARS-COV2 virus causes Coronavirus disease (COVID-19) and represents the causative agent of a potentially fatal disease that is of great global public health concern. The novel coronavirus (2019) was discovered in 2019 in Wuhan, the market of the wet animal, China with viral pneumonia cases and is life-threatening. Today, WHO announces COVID-19 outbreak as a pandemic. COVID-19 is likely to be zoonotic. It is transmitted from bats as intermediary animals to human. Also, the virus is transmitted from human to human who is in close contact with others. The computerized tomographic chest scan is usually abnormal even in those with no symptoms or mild disease. Treatment is nearly supportive; the role of antiviral agents is yet to be established. The SARS-COV2 virus spreads faster than its two ancestors, the SARS-CoV and Middle East respiratory syndrome coronavirus (MERS-CoV), but has lower fatality. In this article, we aimed to summarize the transmission, symptoms, pathogenesis, diagnosis, treatment, and vaccine to control the spread of this fatal disease.


2019 ◽  
Vol 19 (8) ◽  
pp. 567-578 ◽  
Author(s):  
Marcus Vinicius Nora de Souza ◽  
Thais Cristina Mendonça Nogueira

Nowadays, tuberculosis (TB) is an important global public health problem, being responsible for millions of TB-related deaths worldwide. Due to the increased number of cases and resistance of Mycobacterium tuberculosis to all drugs used for the treatment of this disease, we desperately need new drugs and strategies that could reduce treatment time with fewer side effects, reduced cost and highly active drugs against resistant strains and latent disease. Considering that, 4H-1,3-benzothiazin-4-one is a promising class of antimycobacterial agents in special against TB-resistant strains being the aim of this review the discussion of different aspects of this chemical class such as synthesis, mechanism of action, medicinal chemistry and combination with other drugs.


2019 ◽  
Vol 15 (2) ◽  
pp. 138-149
Author(s):  
Saleem Farooq ◽  
Javid A. Banday ◽  
Aashiq Hussain ◽  
Momina Nazir ◽  
Mushtaq A. Qurishi ◽  
...  

Background: Natural product, osthol has been found to have important biological and pharmacological roles particularly having inhibitory effect on multiple types of cancer. Objective: The unmet needs in cancer therapeutics make its derivatization an important and exciting field of research. Keeping this in view, a whole new series of diverse analogues of osthol (1) were synthesized. Method: All the newly synthesized compounds were made through modification in the lactone ring as well as in the side chain of the osthol molecule and were subjected to anti-proliferative screening through 3-(4,5-Dimethylthiazol-yl)-diphenyl tetrazoliumbromide (MTT) against four different human cancers of diverse origins viz. Colon (Colo-205), lung (A549), Leukemia (THP- 1) and breast (MCF-7) including SV40 transformed normal breast epithelial cell (fR-2). Results: Interestingly, among the tested molecules, most of the analogs displayed better antiproliferative activity than the parent Osthol 1. However, among all the tested analogs, compound 28 exhibited the best results against leukemia (THP1) cell line with IC50 of 5µM.Compound 28 induced potent apoptotic effects and G1 phase arrest in leukemia cancer cells (THP1). The population of apoptotic cells increased from 13.8% in negative control to 26.9% at 8μM concentration of 28. Compound 28 also induced a remarkable decrease in mitochondrial membrane potential (ΛΨm) leading to apoptosis of the cancer cells. Conclusion: A novel series of molecules derived from natural product osthol were synthesized, wherein compound 28 was found to be most effective against leukemia and with 10 fold less toxicity against normal cells. The compound induced cancer inhibition mainly through apoptosis and thus has a potential in cancer therapeutics.


2021 ◽  
Vol 52 (1) ◽  
Author(s):  
Peng-Fei Fu ◽  
Xuan Cheng ◽  
Bing-Qian Su ◽  
Li-Fang Duan ◽  
Cong-Rong Wang ◽  
...  

AbstractPseudorabies, caused by pseudorabies virus (PRV) variants, has broken out among commercial PRV vaccine-immunized swine herds and resulted in major economic losses to the pig industry in China since late 2011. However, the mechanism of virulence enhancement of variant PRV is currently unclear. Here, a recombinant PRV (rPRV HN1201-EGFP-Luc) with stable expression of enhanced green fluorescent protein (EGFP) and firefly luciferase as a double reporter virus was constructed on the basis of the PRV variant HN1201 through CRISPR/Cas9 gene-editing technology coupled with two sgRNAs. The biological characteristics of the recombinant virus and its lethality to mice were similar to those of the parental strain and displayed a stable viral titre and luciferase activity through 20 passages. Moreover, bioluminescence signals were detected in mice at 12 h after rPRV HN1201-EGFP-Luc infection. Using the double reporter PRV, we also found that 25-hydroxycholesterol had a significant inhibitory effect on PRV both in vivo and in vitro. These results suggested that the double reporter PRV based on PRV variant HN1201 should be an excellent tool for basic virology studies and evaluating antiviral agents.


Author(s):  
Rathnasagar K ◽  
Thiyagaraj Anand

Objectives: The activity of two different leaf extracts of Lantana indica and Vitex negundo is tested against the 3rd and 4th instar Culex quinquefasciatus larvae to evaluate the potency of the extracts as a larvicide and to find an ecologically sustainable alternative to chemical insecticides. A bioinformatics screening approach was performed to evaluate the in vivo results.Methods: The obtained larvae’s from nearby water sources were tested with N, N-diethyl-meta-toluamide (DEET) as the positive control which is the commercial chemical mosquito repellent and the solvents used for the respective plant extracts act as the negative control. Petroleum ether (PE), ethyl acetate (EA) and an aqueous (AQ) extract were prepared for both L. indica and V. negundo extracts, and its larvicidal activity was tested. A docking based approach was used to study the inhibitory effect of known active compounds from L. indica and V. negundo against acetylcholine esterase (AChE) and sterol binding protein as targets.Results: On comparing the results between three plants extract for its larvicidal activity, the EA extract of V. negundo and L. indica is found to be potent with a low LC50 value. Further, the docking studies between active compounds of L. indica and V. negundo with AChE and Sterol binding protein as targets showed that the compound tangeritin-1 had a good docking score compared to DEET and could be a natural alternative for larvicidal activity in the mosquito.Conclusion: Individual activity of tangeritin-1 could be further studied with mosquito mortality studies and molecular simulations and develop tangeritin-1 as a potential larvicidal compound for commercial use.


e-GIGI ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 238
Author(s):  
Stevia E. Nonutu ◽  
Damajanty H. C. Pangemanan ◽  
Christy N. Mintjelungan

Abstract: One of the treatment options of periodontal abscess caused by Fusobacterium nucleatum is administration of antibiotics. However, long-term antibiotics consumption can cause negative side effects. Therefore, alternative treatments that have low side effects and easy to be obtained are needed. Nike fish (Awaous melanocephalus) is one of the endemic fish of North Sulawesi province which has antibacterial properties. This study was aimed to evaluate the inhibition effect of nike fish extract on the growth of Fusobacterium nucleatum. This was a true experimental study with a posttest only control group design. We used modified Kirby-Bauer method with filter papers. Ciprofloxacin was used as the positive control and aquadest as the negative control. Extract of nike fish and stock of pure bacteria Fusobacterium nucleatum were prepared. The results showed that the average diameters of the inhibition zones formed in the nike fish extract after three repetitions, were as follows: for extract concentration of 12.5% was 2.91 mm; 25% was 4.16 mm; 50% was 8.41 mm; and 100% was 9.58 mm. In conclusion, nike fish extract (Awaous melanocephalus) at concentrations of 50% and 100% had a weak inhibitory effect (Himedia category) on the growth of Fusobacterium nucleatum meanwhile at concentrations of 12.5% and 25% there was no activity of zone of inhibition.Keywords: extract of nike fish (Awaous melanocephalus); Fusobacterium nucleatum; inhibitory effect Abstrak: Salah satu opsi pengobatan abses periodontal yang disebabkan oleh bakteri Fusobacterium nucleatum yaitu dengan penggunaan antibiotik namun mengonsumsi antibiotik jangka panjang dapat menimbulkan efek samping negatif. Oleh karena itu, diperlukan pengobatan alternatif yang memiliki efek samping rendah serta mudah didapat. Ikan nike merupakan salah satu ikan endemik Provinsi Sulawesi Utara yang berkhasiat sebagai antibakteri. Penelitian ini bertujuan untuk mengetahui daya hambat ekstrak ikan nike (Awaous melanocephalus) terhadap pertumbuhan bakteri Fusobacterium nucleatum. Jenis penelitian ialah eksperimental murni dengan post test only control group design. Metode yang digunakan yaitu metode modifikasi Kirby-Bauer dengan menggunakan paper disk. Kontrol positif menggunakan antibakteri ciprofloxacin dan kontrol negatif menggunakan akuades. Pada penelitian ini digunakan ekstrak ikan nike dan stok bakteri murni Fusobacterium nucleatum. Hasil penelitian menunjukkan bahwa rerata diameter zona hambat yang terbentuk pada ekstrak ikan nike setelah tiga kali pengulangan yaitu untuk konsentrasi 12,5% sebesar 2,91 mm; 25% sebesar 4,16 mm; 50% sebesar 8,41 mm; dan 100% sebesar 9,58 mm. Simpulan penelitian ini ialah ekstrak ikan nike (Awaous melanocephalus) pada konsentrasi 50% dan 100% memiliki daya hambat kategori lemah (Himedia) terhadap pertumbuhan bakteri Fusobacterium nucleatum sedangkan pada konsentrasi 12,5% dan 25% dikategorikan tidak terdapat aktivitas zona hambat. Kata kunci: ekstrak ikan nike (Awaous melanocephalus); Fusobacterium nucleatum; daya hambat


2020 ◽  
Vol 148 (3-4) ◽  
pp. 196-202
Author(s):  
Snjezana Petrovic ◽  
Jasmina Basic ◽  
Zoran Mandinic ◽  
Dragana Bozic ◽  
Marina Milenkovic ◽  
...  

Introduction/Objective. Biofilm and pyocyanin production are essential components of Pseudomonas aeruginosa virulence and antibiotic resistance. Our objective was to examine inhibitory effect of synthetized propafenone derivatives 3-(2-Fluorophenyl)- 1-(2- (2-hydroxy-3-propylamino-propoxy)-phenyl)-propan-1-one hydrochloride (5OF) and3-(2- Trifluoromethyl-phenyl)-1-(2-(2-hydroxy-3-propylamino-propoxy)-phenyl)-propan-1-one hydrochloride (5CF3) on biofilm and pyocyanin in Pseudomonas aeruginosa clinical strains. Methods. Effects were tested on nine clinical isolates and one control laboratory strain of P. aeruginosa. In vitro analysis of biofilm growing was performed by incubating bacteria (0.5 McFarland) with 5OF and 5CF3 (500?31.2 ?g/ml) and measuring optical density (OD) at 570 nm. Bacteria in medium without compounds were positive control. Blank medium (an uninoculated medium without test compounds) was used as negative control. Pyocyanin production was estimated by OD at 520 nm, after bacteria incubated with 5CF3 and 5OF (250 and 500 ?g/ml), treated with chloroform, and chloroform layer mixed with HCl. Results. A total of 500 ?g/ml of 5OF and 5CF3 completely inhibited biofilm formation in 10/10 and 4/10 strains, respectively. A total of 250 ?g/ml of 5OF and 5CF3 strongly inhibited biofilm formation in 7/10 strains, while inhibition with 125 ?g/ml of 5OF and 5CF3 was moderate. Lower concentrations had almost no effect on biofilm production. Pyocyanin production was reduced to less than 40% of the control value in 6/9, and less than 50% of the control in 7/9 strains with 500 ?g/ml of 5OF and 5CF3, respectively. At 250 ?g/ml 5OF and 5CF3, most strains had pyocyanin production above 50% of the control value. Conclusion. Synthetized propafenone derivatives, 5OF and 5CF3, inhibited biofilms and pyocyanin production of Pseudomonas aeruginosa clinical strains. Presented results suggest that propafenone derivatives are potential lead-compounds for synthesis of novel antipseudomonal drugs.


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