Proceedings of The Physiological Society

Future Physiology (Leeds, UK) (2017) Proc Physiol Soc 39, PC36

Poster Communications

Indices of functional state after separate and combined use of rhythmic extreme whole body cooling (RE WBC) and cord blood nucleated cells (CBNCs) in old rats

Y. Martynova1, V. Babijchuk1

1. Institute for Problems of Cryobiology and Cryomedicine of the NAS of Ukraine, Kharkiv, Ukraine.

Aging is accompanied with an exhaustion of the regulatory mechanisms (1). WBC (-120°C) can activates the self-regulation processes of the body (2). Stem cell use is promising for regenerative medicine. Taking into account, that RE WBC (-120°C) increases the blood-brain barrier permeability (3), in our study influences of separate and combined use of RE WBC and CBNCs on the indices of functional state of the body in old rats were assessed. Outbred 24-month-aged male rats were divided into 4 groups: control (intact, n=5); RE WBC (n=6), underwent 9 procedures (3/day) of a 2-min cooling (-120°C) (3); CBNCs (n=6), injected intraperitoneally by the ready for use frozen-thawed suspension of human CBNCs (obtained at Institute for Problems of Cryobiology and Cryomedicine (IPC&C) of NAS of Ukraine and prepared by the principles of the Declaration of Helsinki) in dose of CD34+ cells 1×105/kg; and combined group (RE WBC+CBNCs, n=7), injected by the suspension after RE WBC. 30 days after the injection or/and the cooling we evaluated indices of spectral analysis of heart rate variability: total power (TP), high frequency power (HF), low frequency power (LF), very low frequency power (VLF); levels of thyroxine (T4), triiodothyronine (T3), testosterone (Ts) and estradiol (Es) in blood serum, determined by ELISA ; level of the stable end products of nitric oxide (NO) in blood serum, determined by spectrophotometry at 450 nm. The experiments were approved by the Committee in Bioethics at the IPC&C. For parametric analysis (TP, LF, HF, NO, T4, T3) one-way ANOVA with post-hoc Tukey HSD for unequal n, for nonparametric analysis (VLF, Ts, Es, Ts/Es) Kruskal-Wallis ANOVA and multiple comparisons of mean ranks for all groups were used. Significant values were at p<0.05. Values are means±S.E.M. Ts/Es ratio did not differ among the groups. Separate application of RE WBC resulted in a change of VLF (34.04±3.54 vs. 4.80±1.37 ms2), T4 (66.73±2.88 vs. 53.30±0.20 nmol/L) and T3 (4.40±0.32 vs. 3.34±0.27 nmol/L) content. The use of both CBNCs and RE WBC+CBNCs increased TP (105.24±7.42, 114.22±7.87 vs. 43.26±1.53 ms2), LF (31.46±4.33, 36.78±2.25 vs. 16.40±1.26 ms2), HF (65.58±2.70, 68.86±7.36 vs. 22.06±3.00 ms2) and serum NO levels (24.07±3.29, 25.13±3.01 vs. 9.44±0.38 μmol/L); within these two groups, T4 (72.17±1.96 vs. 53.30±0.20 nmol/L) and Ts (7.33±0.76 vs. 2.34±0.20 nmol/L) levels were changed only in RE WBC+CBNCs one, the T3 content was increased (4.83±0.18 vs. 3.34±0.27 nmol/L) in CBNCs one. However, in view of the lack of change in Ts/Es ratio (in 30 days term), we can suggest that such rise could be non-binding in a biological implication for the body. Thus, the combined use of RE WBC and CBNCs in old rats is comparable to the separate use of CBNCs and mostly differs from the separate application of RE WBC.

Where applicable, experiments conform with Society ethical requirements