Regulatory mechanisms of miR-96 and miR-184 abnormal expressions on otic vesicle development of zebrafish following exposure to β-diketone antibiotics

Abstract

Chronic ototoxicity of β-diketone antibiotics (DKAs) to zebrafish (Danio rerio) was explored in detail by following abnormal expressions of two hearing-related miRNAs. Dose-dependent down-regulation of miR-96 and miR-184 was observed in otoliths during embryonic-larval development. Continuous DKA exposure to 120-hpf larva decreased sensitivity to acoustic stimulation. Development of otolith was delayed in treatment groups, showing unclear boundaries and vacuolization at 72-hpf, and utricular enlargement as well as decreased saccular volume in 96-hpf or latter larval otoliths. If one miRNA was knocked-down and another over-expressed, only a slight influence on morphological development of the otic vesicle occurred, but knocked-down or over-expressed miRNA both significantly affected zebrafish normal development. Injection of miR-96, miR-184 or both micRNA mimics to yolk sac resulted in marked improvement of otic vesicle phenotype. However, hair cell staining showed that only the injected miR-96 mimic restored hair cell numbers after DKA exposure, demonstrating that miR-96 played an important role in otic vesicle development and formation of hearing, while miR-184 was only involved in otic vesicle construction during embryonic development. These observations advance our understanding of hearing loss owing to acute antibiotic exposure and provide theoretical guidance for early intervention and gene therapy for drug-induced diseases.

Zebrafish as a Screening Model to Study the Single and Joint Effects of Antibiotics

“…Wang and co-workers provided important information concerning the joint effects of β-diketone antibiotic mixture exposure on zebrafish. They demonstrated that the exposure to fluoroquinolones and tetracyclines can induce dysfunction of the immune system, liver and heart; damage the antioxidant defense system; and cause reproductive failure, skeletal disorders and neurotoxicity effects [ 30 , 31 , 35 , 37 , 112 , 113 , 114 ]. Briefly, treatments with DKAs affect a variety of cellular and biological processes in zebrafish.…”

“…Additional studies proved that treatments with β-diketone antibiotic mixtures led to abnormal development of otoliths in zebrafish embryos and a decreased sensitivity to acoustic stimulation, which implies the occurrence of hearing impairment [ 31 ]. Notably, the miR-96 and miR-184 were identified as key factors regarding the molecular mechanisms regulating hearing functions.…”

“…Most of the research papers on this topic have reported that the zebrafish health or/and its capacity to respond to environmental changes are affected following both acute and chronic exposure to antibiotics. The toxicological effects of single and mixed antibiotics in zebrafish were studied by proteomic [ 30 ] and transcriptome sequencing [ 31 , 32 ], examination of behavioral activities [ 28 , 33 , 34 ] and biomarkers [ 35 , 36 ], histopathological analysis of various tissues [ 30 , 37 ], fish lethality assays (LC 50 ) [ 22 , 38 , 39 ] and following the fish morphological changes [ 40 ]. Antibiotics were found to interfere with the bacterial communities of zebrafish gut and with fish development, causing malformations, such as hatching delay, shorter body length, yolk sac edema, curved body axis and pericardial edema [ 23 , 25 , 41 , 42 , 43 , 44 ].…”

Integrated Analysis of mRNA- and miRNA-Seq in the Ovary of Rare Minnow Gobiocypris rarus in Response to 17α-Methyltestosterone

“…In another study, miR-19 was reported to directly target the TGFβ pathway associated with the inflammation pathway (Li et al, 2012), whereas the miR-130a-fabp3 pair was reported to play a vital role in the PI3K/AKT-mTOR pathway (Chen et al, 2018). Recent studies reported that miR-96 was important in otic vesicle development, involved in the hearing process, along with miR-183 (target mfap4) (Li et al, 2010;Kim et al, 2018), and in the formation of the nervous system in conjunction with miR-184 (Li et al, 2016(Li et al, , 2019. LncRNA UCA1 promotes cell proliferation by upregulating Foxo3 and downregulating miR-96 (Zhou et al, 2018).…”

Role of microRNAs as novel diagnostic biomarkers and potential therapeutic targets for hearing disorders (Review)

“…subsequently, Li et al (105) conducted an in vivo study on zebrafish embryos to evaluate the association between β-diketone antibiotic-induced ototoxicity and the regulatory role of miRNAs in hearing. Firstly, they noted a decreased response to acoustic stimuli in the treatment group compared to the controls.…”