Tityus serrulatus envenoming in non-obese diabetic mice: a risk factor for severity

 

Guilherme Honda de Oliveira¹, Felipe Augusto Cerni¹, Iara Aimê Cardoso¹, Eliane Candiani Arantes¹, Manuela Berto Pucca^1 2

 

1 Department of Physics and Chemistry, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo (USP), Av. do Café, s/n, 14040-903 Ribeirão Preto, SP, Brazil

2 Medical School of Roraima, Federal University of Roraima (UFRR), Av. Capitão Ene Garcez, 2413, Boa Vista, RR 69310-000, Brazil

 

ABSTRACT

 

Background

In Brazil, accidents with venomous animals are considered a public health problem. Tityus serrulatus (Ts), popularly known as the yellow scorpion, is most frequently responsible for the severe accidents in the country. Ts envenoming can cause several signs and symptoms classified according to their clinical manifestations as mild, moderate or severe. Furthermore, the victims usually present biochemical alterations, including hyperglycemia. Nevertheless, Ts envenoming and its induced hyperglycemia were never studied or documented in a patient with diabetes mellitus (DM). Therefore, this is the first study to evaluate the glycemia during Ts envenoming using a diabetic animal model (NOD, non-obese diabetic).

 

Methods

Female mice (BALB/c or NOD) were challenged with a non-lethal dose of Ts venom. Blood glucose level was measured (tail blood using a glucose meter) over a 24-h period. The total glycosylated hemoglobin (HbA1c) levels were measured 30 days after Ts venom injection. Moreover, the insulin levels were analyzed at the glycemia peak.

 

Results

The results demonstrated that the envenomed NOD animals presented a significant increase of glycemia, glycosylated hemoglobin (HbA1c) and insulin levels compared to the envenomed BALB/c control group, corroborating that DM victims present great risk of developing severe envenoming. Moreover, the envenomed NOD animals presented highest risk of death and sequelae.

 

Conclusions

This study demonstrated that the diabetic victims stung by Ts scorpion should be always considered a risk group for scorpion envenoming severity.

 

Key words: Tityus serrulatus; Diabetes mellitus; Scorpion venom; NOD mice; Glycemia

 

Funding

This study received financial support from the State of São Paulo Research Foundation (FAPESP –scholarships to MBP 2012/12954-6 and FAC 2012/13590-8), the National Council for Scientific and Technological Development (CNPq – scholarship to GHO) and NAP-TOXAN-USP (grant n. 12e125432.1.3).

 

Ethics approval and consent to participate

The present study was approved by the Ethics Commission for the Use of Animals (CEUA) at the USP Campus in Ribeirão Preto (protocol number 13.1.372.53.0). The use of Ts venom was approved by the Genetic Patrimony Management Board (CGEN/MMA), through the Access and Shipment Component of Genetic Heritage for scientific research purposes (number 010174/2014-1).

 

Additional file 1: Representative comparison of eyeball of Ts envenomed and non-envenomed mice. Mice were injected with Ts venom (1 mg/kg). (A) Envenomed NOD mice with glucose basal level ≥ 200 mg/dL, retinopathy indication. (B) Envenomed BALB/c mice, typical ptosis. (C) BALB/c mice control (non-envenomed), normal eyeball. (PPTX 81 kb)

 

Received: March 29, 2016.

Revised: September 2, 2016.

Accepted: September 17, 2016.

 

Correspondence: manu.pucca@ufrr.br

 

Authors’ contributions

GHO was the baccalaureate student (Iniciação Científica) responsible for the project, and was involved in the organization and execution of the experimentation section, data acquisition, statistical analysis and data interpretation, as well as drafting and revising the manuscript. MBP and ECA were the advisor researchers of this project and critically revised the manuscript for its content. FAC and IAC substantially contributed to the experimental execution and revision of the manuscript. All authors read and approved the final manuscript.

 

Competing interests

The authors declare that they have no competing interests.

 

doi: 10.1186/s40409-016-0081-8