Inhibition by Marine Algae of Chikungunya Virus Isolated From Patients in a Recent Disease Outbreak in Rio de Janeiro

Abstract

Chikungunya virus (CHIKV) infection is one of the most challenging re-emergent diseases caused by a virus, and with no specific antiviral treatment it has now become a major public health concern. In this investigation, 25 blood samples were collected from patients with characteristic CHIKV symptoms and submitted to a virus isolation protocol, which detected 3 CHIKV isolates. These samples were evaluated by sequencing for the characterization of the strains and any homology to viruses circulating in Brazil during a recent outbreak. These viruses were used for the development of antiviral assays. Subsequently, the inhibitory effects of seaweed extracts on CHIKV replication were studied. The marine species of algae tested were Bryothamnion triquetrum, Caulerpa racemosa, Laurencia dendroidea, Osmundaria obtusiloba, Ulva fasciata, and Kappaphycus alvarezii, all of which are found in different countries including Brazil. The results revealed high levels of CHIKV inhibition, including extracts of O. obtusiloba with inhibition values of 1.25 μg/mL and a selectivity index of 420. Viral inhibition was dependent on the time of addition of extract of O. obtusiloba to the infected cells, with the optimal inhibition occurring up to 16 h after infection. Neuron evaluations with O. obtusiloba were performed and demonstrated low toxicity, and in infected neurons we observed high inhibitory activity in a dose-dependent manner. These results indicate that the algal extracts may be promising novel candidates for the development of therapeutic agents against CHIKV infections.

Antiviral activity of sulfated polysaccharides from marine algae and its application in combating COVID-19: Mini review

“…The sulfated polysaccharides of seaweeds have been shown to exhibit antiviral activity against a broad spectrum of viruses. It has been reported to inhibit antiviral activity against Herpes Simplex virus (HSV) ( Gomaa and Elshoubaky, 2016 ), Human immunodeficiency virus type-1 (HIV-1) ( Besednova et al, 2019 ), chikungunya virus ( Cirne-Santos et al, 2019 ), and many other enveloped and non-enveloped viruses. Also, the antiviral activity of SPs against the currently on-going pandemic coronavirus disease 2019 (COVID-19) is reported ( Chen et al, 2020 ).…”

Dietary supplementation of Ascophylum nodosum improved kidney function of mink challenged with Aleutian mink disease virus

“…Recent in vitro studies revealed that seaweed extracts have anti-herpes simplex virus (HSV-1, NSV-2) [6,7], anti-human immunodeficiency virus (HIV-1) [7,8], antichikungunya virus [9], anti-enterovirus (ECHO-1) [7] properties and inactivated measles virus [10] to name a few. Extensive reviews suggest that seaweed extracts can block virus-host attachment, virus entry to the cell or inhibit the replication of several types of enveloped viruses in vitro [11][12][13][14][15][16].…”

Nitrogen-Based Heterocyclic Compounds: A Promising Class of Antiviral Agents against Chikungunya Virus

“…A series of thioguanine-coumarins derivatives were studied, and the methoxylated coumarins [54] (21, 22 and 23) exhibited the best activities against CHIKV compared to the benzouracil coumarins (9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19). EC 50 values were below 13.9 µM with a significant selectivity window covering SI values between 9.37 and 21.7, whereas the molecular lipophilicity of 20, 21, 22 and 23 were between 2.97 and 3.77.…”

“…CHIKV has a single-strand, positive-polarity RNA genome, whose size varies between 9.7 and 12 kb [ 13 ]. The viral particles, which are often spherical, have a diameter of 70 nm and an isometric nucleocapsid of 40 nm [ 14 ]. The proteins are encoded by two open reading frames (ORFs) in which the first two-thirds of the genome from the 5′ end is responsible for expression of the non-structural proteins (NSPs) named nsP1, nsP2, nsP3, and nsP4; whereas the last one-third located at the 3′ end codifies a subgenomic RNA that originates from three structural proteins and two peptides: capsid (C), enveloped glycoprotein 1 (E1), glycoprotein enveloped 2 (E2), E3, and 6K [ 1 , 15 , 16 ].…”

“…To date, four CHIKV genotypes have been described: Asian, East Indian, West African, and East/Central/South African. The Asian genotype was first detected in the Caribbean region in late 2013 and then spread throughout Central America [ 14 ].…”