A low direct electrical signal attenuates oxidative stress and inflammation in septic rats

Abstract

Electrical stimulation is proposed to exert an antimicrobial effect according to studies performed using bacterial and cell cultures. Therefore, we investigated the effects of electrification on inflammation in septic rats. Twenty-eight male Wistar albino rats were divided into 4 groups: healthy control (C), electrified healthy (E), sepsis (S), and electrified sepsis (SE) groups. Staphylococcus aureus (1 x 109 colonies) in 1 ml of medium was intraperitoneally injected into rats to produce a sepsis model. The rats in the E and SE groups were exposed to a low direct electrical signal (300 Hz and 2.5 volts) for 40 min and 1 and 6 h after bacterial infection. Immediately after the second electrical signal application, blood and tissue samples of the heart, lung, and liver were collected. An antibacterial effect of a low direct electrical signal was observed in the blood of rats. The effects of electrical signals on ameliorating changes in the histological structure of tissues, blood pH, gases, viscosity and cell count, activities of some important enzymes, oxidative stress parameters, inflammation and tissue apoptosis were observed in the SE group compared to the S group. Low direct electrical signal application exerts antibacterial, antioxidant, anti-inflammatory and antiapoptotic effects on septic rats due to the induction of electrolysis in body fluids without producing any tissue damage.

Conflict of interest statement

This study was supported by AVB Biotech, Barbaros Street, Deluxia Palace, Number: 3/40, Istanbul, Turkey. ST and ST designed and developed Dr. Biolyse, and RA, IK and GBT are employees of AVB Biotech, the sponsor of the study, and they participated in the application of Dr. Biolyse. IM and SU also serve as scientific advisors to BVU Biotech for Dr. Biolyse. Other authors do not have any conflicts of interest to declare. This statement does not alter our adherence to PLOS ONE policies on sharing data and materials.

Figures

Fig 1. The Dr. Biolyse.

Rats were exposed to a low electrical signal using the newly developed Dr. Biolyse device.

Fig 2. The number of bacteria measured during experiments.

Bacterial counts of the healthy control (C) electrified healthy (E), sepsis (S) and electrified sepsis (SE) groups (n = 7). ***; p<0.001 statistically significant difference compared to the S group.

Fig 3. Histological results obtained after the Dr. Biolyse treatment.

Images of hematoxylin & eosin staining in sections from the healthy control (C), electrified healthy (E), sepsis (S) and electrified sepsis (SE) groups at X400 magnification. Insets show the lung tissues of the S and SE groups at low magnification. Here, inflammation was greater in the S group than in the SE group (HE X10). Stars in insets in the pictures of the liver section from S group show the necrotic liver tissue (HE X10).

Fig 4. The blood parameters measured after the Dr. Biolyse treatment.

The blood pH and gases of the healthy control (C) electrified healthy (E), sepsis (S) and electrified sepsis (SE) groups (n = 7). pH (A), pO2 (B), pCO2 (C) and sO2 (D) are presented as the means ± SD. *; p<0.05, ***; p<0.001 statistically significant difference compared to the C group. +++; p<0.001 statistically significant difference compared to the S group.

Fig 5. The white blood cell count.

The blood leukocyte counts of the healthy control (C) electrified healthy (E), sepsis (S) and electrified sepsis (SE) groups (n = 7). WBC (A), white blood cells; LY% (B), lymphocyte %; MONO% (C), monocyte %; GR% (D), granulocyte %. Data are presented as the means ± SD. *; p<0.05, **; p<0.01 statistically significant difference compared to the C group. +; p<0.05, ++; p<0.01 statistically significant difference compared to the S group.

Fig 6. The blood hemogram parameters.

The blood erythrocyte and thrombocyte counts and hemoglobin and hematocrit levels in the healthy control (C), electrified healthy (E), sepsis (S) and electrified sepsis (SE) groups (n = 7). RBC (A), red blood cell; HB (B), hemoglobin; HCT (C), hematocrit; and PLT (D), platelet. Data are presented as the mean ± SD. *; p<0.05, ***; p<0.001 statistical significance compared to the C group. +; p<0.05, ++; p<0.01, +++; p<0.001 statistical significance compared to the S group.

Fig 7. The blood rheological parameters.

The blood viscosity and shear stress levels of the healthy control (C) electrified healthy (E), sepsis (S) and electrified sepsis (SE) groups (n = 7). Viscosity (A) and shear stress (B). Data are presented as the means ± SD. *; p<0.05, **; p<0.01 statistically significant difference compared to the C group. +++; p<0.001 statistically significant difference compared to the S group.

Fig 8. Relative protein expression of the proinflammatory cytokine IL-1β.

A) Images of liver, B) heart, and C) lung tissues from healthy control (C), electrified healthy (E), sepsis (S) and electrified sepsis (SE) groups. D) Representative images of IL-1β expression in the studied tissues. Values are presented as the means ± SD. Comparisons were performed between the C group and the S group (*; p<0.05 and ***; p<0.001) and between the S group and the SE group. (+; p<0.05 and ++; p <0.01).

Fig 9. The relative protein expression of the proinflammatory cytokine TNF-α.

A) Images of the liver, B) heart, and C) lung tissues from the healthy control (C), electrified healthy (E), sepsis (S) and electrified sepsis (SE) groups. D) Representative pictures of TNF-α expression in the studied tissues are shown. Values are presented as the means ± SD. Comparisons were performed between the C group and the S group (*; p<0.05 and **; p<0.01) and between the S group and the SE group. (+; p<0.05).

Fig 10. The relative ratio of expression of the proapoptotic protein Bax to the antiapoptotic protein Bcl-2.

A) Data from the liver, B) heart, and C) lung tissues from the healthy control (C), electrified healthy (E), sepsis (S) and electrified sepsis (SE) groups. D) Representative pictures of Bax and Bcl-2 expression in the studied tissues. Values are presented as the means ± SD. Comparisons were performed between the C group and the S group (*; p<0.05) and between the S group and the SE group. (+; p<0.05 and ++; p<0.01).