Vitamin C ameliorated cardiac autonomic neuropathy in type 2 diabetic rats

Table 1 Heart rate variability in type 2 diabetic rats

HRV Indices	Control	Diabetic	Vitamin C
HR (bpm)	282.2 ± 8	78.3 ± 17.5c	277.8 ± 11
RR Interval (ms)	220.5 ± 14	872.5 ± 94d	222.7 ± 13
Max/Min RR	3.4 ± 0.2	1.4 ± 0.2a	3.5 ± 0.1
SDNN (ms)	72.1 ± 11	48.6 ± 1.6a	68.2 ± 7
RMSSD (ms)	107.5 ± 11.5	65.1 ± 1.0b	98 ± 13
TP (ms2)	45159.3 ± 7839	290.4 ± 0.5d	44927.8 ± 7832
LF (ms2)	5434 ± 877	126.5 ± 4.6d	5338.7 ± 1198
HF (ms2)	19574.1 ± 4019	108.4 ± 7d	14634.1 ± 4866
nLF	5.9 ± 2.3	44.2 ± 2c	5.7 ± 1
nHF	16.2 ± 3.4	38.5 ± 2a	13.4 ± 3

Results are presented as mean ± SE, n = 10;

^aP < 0.05,

^bP < 0.01,

^cP < 0.001,

^dP < 0.0001, significantly different from control. HRV: Heart rate variability; HR: Heart rate; RR interval: Interval between two QRS wave complex; SDNN: Standard deviation of successive normal intervals; RMSSD: Root mean square of the difference between successive normal RR interval; TP: Total power; LF: Low frequency; HF: High frequency; nLF: Normalised low frequency; nHF: Normalised high frequency.

Table 2 Markers of oxidative stress and inflammation

Markers	Control	Diabetic	VC treated
MPO (µmol/mL/mg protein)	1.63 ± 0.3	2.3 ± 0.07a	1.62 ± 0.31
NO (M/dL)	9.5 ± 0.3	20.1 ± 0.6b	8.7 ± 1.11
SOD (unit SOD/min)	0.7 ± 0.1	1.4 ± 0.04b	0.6 ± 0.11
LPO (nmol/mg protein)	8.1 ± 1.0	16.4 ± 1.2b	8.6 ± 0.71
GSH (mg/dL)	11.3 ± 1.0	5.89 ± 0.8b	9.2 ± 1.91
AA (µg/mL)	61 ± 10.6	39.2 ± 2.0b	62.3 ± 6.21

Results are mean ± SE, n = 10;

¹No significant difference from control;

^aP < 0.05,

^bP < 0.01, significantly different from control. MPO: Myeloperoxidase; NO: Nitric oxide; SOD: Super oxide dismutase; MDA: Malondialdehyde; GSH: Glutathione; AA: Ascorbic acid.