Single-walled carbon nanotubes as drug carrier loaded with moroxydine hydrochloride against infectious spleen and kidney necrosis virus in mandarin fish

Abstract

Infectious diseases of viral origin cause major aquatic production losses in different parts of the world. There are lots of limited therapeutic effects for large amounts of antiviral drugs because of several impenetrable barriers (cell, skin, and gastrointestinal tract). In this study, we selected moroxydine hydrochloride (Mor) for the treatment of infectious spleen and kidney necrosis virus (ISKNV) and choose single-walled carbon nanotubes (SWCNTs) as drug carrier by immersion bath on mandarin fish infected with ISKNV. The results showed that increasing Mor intake was observed by SWCNTs carrier and therapeutic dosage to kill ISKNV is significantly reduced. After 4 h treatment, the concentration of Mor was 103.48 μg/g in 40 mg/L Mor group, and 182.35 μg/g in 40 mg/L Mor-SWCNTs groups. Comparing with the same dosage in Mor group, the detention time of Mor was extended more than 48 h in Mor-SWCNTs group. After 11 d treatment, cumulative mortality was 11.51% and infection rate was 3.81% in 40 mg/L Mor-SWCNTs group. In the same dosage of Mor group, cumulative mortality was 43.34% and infection rate was 22.67%. Moreover, enzyme activities, complement (C3) content and immune-related genes expression were significantly increased in Mor and Mor-SWCNTs groups than control group, herein all these mentioned activities reached the highest level at 3 days post-treatment. Our results indicated that drug delivery with functionalized SWCNTs can improve the antiviral effect on mandarin fish and has a potential application value to control fish viral diseases in aquaculture.