Effect of electrical stimulation on human immunodeficiency virus type-1 infectivity

Reduction of Viral and Bacterial Activity by Using a Self-Powered Variable-Frequency Electrical Stimulation Device

Viruses and bacteria, which can rapidly spread through droplets and saliva, can have serious effects on people's health. Viral activity is traditionally inhibited using chemical substances, such as alcohol or bleach, or physical methods, such as thermal energy or ultraviolet-light irradiation. However, such methods cannot be used in many applications because they have certain disadvantages, such as causing eye or skin injuries. Therefore, in the present study, the electrical stimulation method is used to stimulate a virus, namely, coronavirus 229E, and two types of bacteria, namely, Escherichia coli and Staphylococcus aureus, to efficiently reduce their infectivity of healthy cells (such as the Vero E6 cell in a viral activity-inhibition experiment). The infectivity effects of the aforementioned virus and bacteria were examined under varying values of different electrical stimulation parameters, such as the stimulation current, frequency, and total stimulation time. The experimental results indicate that the activity of coronavirus 229E is considerably inhibited through direct-current pulse stimulation with a current of 25 mA and a frequency of 2 or 20 Hz. In addition, E. coli activity was reduced by nearly 80% in 10 s through alternating-current pulse stimulation with a current of 50 mA and a frequency of 25 Hz. Moreover, a self-powered electrical stimulation device was constructed in this study. This device consists of a solar panel and battery to generate small currents with variable frequencies, which has advantages of self-powered and variable frequencies, and the device can be utilized on desks, chairs, or elevator buttons for the inhibition of viral and bacterial activities.

Detecting free radicals post viral infections

Free radical generation plays a key role in viral infections. While free radicals have an antimicrobial effect on bacteria or fungi, their interplay with viruses is complicated and varies greatly for different types of viruses as well as different radical species. In some cases, radical generation contributes to the defense against the viruses and thus reduces the viral load. In other cases, radical generation induces mutations or damages the host tissue and can increase the viral load. This has led to antioxidants being used to treat viral infections. Here we discuss the roles that radicals play in virus pathology. Furthermore, we critically review methods that facilitate the detection of free radicals in vivo or in vitro in viral infections.

Sensitivity to electrical stimulation of human immunodeficiency virus type 1 and MAGIC-5 cells

To determine the sensitivities to low electrical potential of human immunodeficiency virus type 1 (HIV-1) and its target cells, HIV-1 and MAGIC-5 cells were directly stimulated with a constant direct current potential of 1.0 V (vs. Ag/AgCl). HIV-1 was incubated for 3 h at 37°C on a poly-L-lysine-coated indium-tin oxide electrode, and then stimulated by an electrical potential. MAGIC-5 cells were seeded onto the electrically stimulated HIV-1 and cultured for 3 days at 37°C. HIV-1-infected cells were measured by multinuclear activation via a galactosidase indicator assay. MAGIC-5 cells were also stimulated by an electrical potential of 1.0 V; cell damage, proliferation and apoptosis were evaluated by trypan blue staining, cell counting and in situ apoptosis detection, respectively. HIV-1 was found to be damaged to a greater extent by electrical stimulation than the cells. In particular, after application of a 1.0-V potential for 3 min, HIV-1_LAI and HIV-1_KMT infection were inhibited by about 90%, but changes in cell damage, proliferation and apoptosis were virtually undetectable. These results suggested that HIV-1 is significantly more susceptible to low electrical potential than cells. This finding could form the basis of a novel therapeutic strategy against HIV-1 infection.