Intravenous Single Dose Toxicity of Sweet Bee Venom in Sprague-Dawley Rats

Objectives:

Anaphylactic shock can be fatal to people who become hypersensitive when bee venom pharmacopuncture (BVP) is used. Thus, sweet bee venom (SBV) was developed to reduce these allergic responses. SBV is almost pure melittin, and SBV has been reported to have fewer allergic responses than BVP. BVP has been administered only into acupoints or intramuscularly, but we thought that intravenous injection might be possible if SBV were shown to be a safe medium. The aim of this study is to evaluate the intravenous injection toxicity of SBV through a single-dose test in Sprague-Dawley (SD) rats.

Methods:

Male and female 6-week-old SD rats were injected intravenously with SBV (high dosage: 1.0 mL/animal; medium dosage: 0.5 mL/animal; low dosage: 0.1 mL/animal). Normal saline was injected into the control group in a similar method. We conducted clinical observations, body weight measurements, and hematology, biochemistry, and histological observations.

Results:

No death was observed in any of the experimental groups. Hyperemia was observed in the high and the medium dosage groups on the injection day, but from next day, no general symptoms were observed in any of the experimental groups. No significant changes due to intravenous SBV injection were observed in the weights, in the hematology, biochemistry, and histological observations, and in the local tolerance tests.

Conclusion:

The results of this study confirm that the lethal dose of SBV is over 1.0 mL/animal in SD rats and that the intravenous injection of SBV is safe in SD rats.

Study on a 4-week recovery test of sweet bee venom after a 13-week, repeated, intramuscular dose toxicity test in sprague-dawley rats

Objectives:

This study was performed to check for reversibility in the changes induced by a 13-week, repeated, dose toxicity test of Sweet Bee Venom (SBV) in Sprague-Dawley (SD) rats.

Methods:

Fifteen male and 15 female SD rats were treated with 0.28 mg/kg of SBV (high-dosage group) and the same numbers of male and female SD rats were treated with 0.2 mL/kg of normal saline (control group) for 13 weeks. We selected five male and five female SD rats from the high-dosage group and the same numbers of male and female SD rats from the control group, and we observed these rats for four weeks. We conducted body-weight measurements, ophthalmic examinations, urinalyses and hematology, biochemistry, histology tests.

Results:

(1) Hyperemia and movement disorder were observed in the 13-week, repeated, dose toxicity test, but these symptoms were not observed during the recovery period. (2) The rats in the high-dose group showed no significant changes in weight compared to the control group. (3) No significant differences in the ophthalmic parameters, urine analyses, complete blood cell counts (CBCs), and biochemistry were observed among the recovery groups. (4) No changes in organ weights were observed during the recovery period. (5) Histological examination of the thigh muscle indicated cell infiltration, inflammation, degeneration, necrosis of muscle fiber, and fibrosis during the treatment period, but these changes were not observed during the recovery period. The fatty liver change that was observed during the toxicity test was not observed during the recovery period. No other organ abnormalities were observed.

Conclusion:

The changes that occurred during the 13-week, repeated, dose toxicity test are reversible, and SBV can be safely used as a treatment modality.