Effects of chronic decaffeinated green tea extract supplementation on lipolysis and substrate utilization during upper body exercise

Background:Decaffeinated green tea extract(dGTE)can increase fat oxidation during leg exercise,but dGTE is unsuitable for many people(e.g.,those with injuries/disabilities),and its effects on arm exercise and women are unknown.Methods:Eight adults(23-37 years old,4 women)performed an incremental arm cycle test to measure peak oxygen uptake(VO_(2_(peak))),followed by four 1-h trials at 50%VO_(2_(peak).Subjects were randomly assigned to 650 mg of dGTE or placebo(PLA)for 4 weeks followed by a 4-week washout and crossover trial.Blood samples were obtained pre-exercise and post-exercise for glycerol and free fatty acid analysis.Respiratory gases were collected continuously.Results:VO_(2) showed no differences across trials((0.83-0.89)±(0.19-0.25)L/min,p=0.460),neither did energy expenditure((264-266)±(59-77)kcal,p=0.420)nor fat oxidation(dGTE=0.11 to 0.12 g/min vs.PLA=0.10 to 0.09 g/min,p=0.220).Fat oxidation as percentage of energy expenditure was not different for dGTE vs.PLA(23%±12%to 25%±11%vs.23%±10%to 21%±9%,p=0.532).Glycerol concentration increased post-exercise in all trials,independent of treatments(pre=(3.4-5.1)±(0.6-2.6)mg/dL vs.post=(7.9-9.8)±(2.6-3.7)mg/dL,p=0.867,η^(2)=0.005 for interaction),as did free fatty acid((3.5-4.8)±(1.4-2.2)mg/dL vs.(7.2-9.1)±(2.6-4.5)mg/dL,p=0.981,η^(2)=0.000).Conclusion:Chronic dGTE supplementation had no effect on lipolysis and fat oxidation during arm cycle exercise in men and women.

Maternal intake restriction programs the energy metabolism, clock circadian regulator and m TOR signals in the skeletal muscles of goat offspring probably via the protein kinase A-cAMP-responsive element-binding proteins pathway

The biological mechanism by which maternal undernutrition increases the metabolic disorder risk of skeletal muscles in offspring is not fully understood.We hypothesize that maternal intake restriction influences metabolic signals in the skeletal muscles of offspring via a glucagon-mediated pathway.Twentyfour pregnant goats were assigned to the control group(100%of the nutrients requirement,n=12)and restricted group(60%of the control feed allowance from pregnant days 45 to 100,n=12).Blood and Longissimus thoracis muscle were sampled from dams(100 d of gestation),fetuses(100 d of gestation),and kids(90 d after birth)in each group.The data were analyzed using the linear MIXED model,with the multiple comparison method of SIDAK applied.Intake restriction reduced(P<0.05)the total blood protein of dams and fetuses.Maternal restriction decreased(P<0.05)the cAMP-responsive element-binding protein 1(CREB1),CREB-binding protein(CREBBP),protein kinase A(PKA),aryl hydrocarbon receptor nuclear translocator-like protein 1(BMAL1),protein kinase B(AKT1),mammalian target of rapamycin(mTOR),and regulatory-associated protein of mTOR(RPTOR)mRNA expression in the fetuses,and reduced(P<0.05)the CREBBP,nuclear receptor subfamily 1 group H member 3(NR1 H3),D-box binding PAR bZIP transcription factor(DBP)and PKA mRNA levels in the kids,but increased(P<0.05)the peroxisome proliferator-activated receptor gamma coactivator 1 alpha(PGC1 A)and tuberous sclerosis 2(TSC2)mRNA levels in the fetuses.The mRNA expression of clock circadian regulator(CLOCK)and TSC2 genes was increased(P<0.05)in the restricted kids.The protein expression of total PKA and phosphorylated PKA in the restricted fetuses and kids were downregulated(P<0.05),and the protein expression of total mTOR and phosphorylated mTOR were reduced(P<0.05)in the restricted fetuses and kids.Maternal intake restriction regulated fat oxidation,protein synthesis,and circadian clock expression in the muscles of the offspring probably via the glucagon-mediated PKA-CREB pathway,which reveals a noteworthy molecular pathway that maternal undernutrition leads to metabolic adaptation of skeletal muscle in offspring.