Metabolic syndrome--Pathophysiology.

BDNF is a neurotrophin that enhances neural health and is increased by exercise.
PURPOSE: To compare moderate continuous (MCE) and high-intensity interval exercise
(HIE) effects on serum BDNF levels, and examine the relationship between BDNF and
lactate. METHODS: Seven males completed a VO2peak test and two protocols on
separate days, (MCE) 28 min at 60% Workrate max (WRmax) and (HIE) 28 min of
intervals at 90%WRmax (10- 1 min intervals separated by 2 min of rest). Serum BDNF
and lactate were determined prior, during, and following both protocols. RESULTS:
BDNF levels (pg/mL) increased from baseline during HIE and MCE (p<.05). The BDNF
response to HIE correlated with lactate for area under the curve (AUC) (r=0.901;
P<0.05). CONCLUSION: HIE is an effective alternative to MCE at increasing BDNF.
Additionally, lactate may act as a measure of intensity or a mediator of the BDNF
response to exercise.

Obesity is associated with elevated levels of the pro-inflammatory cytokines
interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α), contributing to systemic
insulin resistance. Fibroblast growth factor 21 (FGF21) is a vital metabolic and
inflammatory regulator, however circulating FGF21 concentrations are elevated in obese
individuals. Acute aerobic exercise increases systemic FGF21 in normal-weight
individuals, however the effect of acute aerobic exercise on plasma FGF21 response and
the relationships with inflammation (IL-6 and TNF-α), insulin resistance, and energy
expenditure in obese individuals is unknown. Following 30 minutes of treadmill running
at 75% VO2max, plasma FGF21 response, as indicated by area-under-the-curve “with
respect to increase” (AUCi) analyses, was attenuated in 12 obese compared to 12 normalweight
subjects. Additionally, FGF21 AUCi positively correlated with glucose AUCi,
total relative energy expenditure, and relative VO2max, suggesting that cardiorespiratory fitness levels may predict FGF21 response, contributing to the enhanced regulation of
glucose and energy metabolism.