Omega-3 和乳清蛋白补充剂对老年人瘦体重的影响 (W-3 and Whey)

Group supplemented with maltodextrin (38g/day) and sunflower oil (5g/day). All groups will undergo a training program with strength exercises for 12 weeks

The placebo group will receive 5 g per day of sunflower oil and 38 g per day of maltodextrin.

Group supplemented with isolated whey protein (38g/day) and sunflower oil (5g/day). All groups will undergo a training program with strength exercises for 12 weeks.

The whey protein + placebo group will receive 38g per day of whey and 5g per day of sunflower oil.

Group supplemented with omega-3 (5g/day) and maltodextrin (38g/day). All groups will undergo a training program with strength exercises for 12 weeks.

The omega 3 + placebo group will receive 5 g per day of fish oil and 38 g per day of maltodextrin.

Group supplemented with omega-3 (5g/day) and whey protein (38g/day). All groups will undergo a training program with strength exercises for 12 weeks.

The omega 3 + whey group will receive 5g per day of fish oil and 38g per day of protein.

Oxidative stress biomarkers will be assessed in blood and saliva, whereas inflammatory biomarkers will be assessed in blood only. Blood and saliva samples will be collected before and after the intervention. After an overnight fast, 20 mL of blood will be collected into heparinized tubes. A portion of the blood will be used for whole-blood stimulation with or without 10 ng/mL lipopolysaccharide (LPS; Escherichia coli O111) for 6 hours at 37°C in 5% CO₂. Following incubation, the supernatant will be collected for the assessment of inflammatory cytokines by ELISA. The remaining blood will be centrifuged at 4°C and 3,200 rpm for 10 minutes, aliquoted, and stored at -80°C until analysis of oxidative stress biomarkers.

For metabolomic analysis, 100 μL of serum will be extracted with spectroscopic-grade methanol, homogenized, centrifuged, concentrated under vacuum, reconstituted in methanol, and filtered through a 0.22-μm filter. For lipidomic analysis, 100 μL of serum will be extracted using dichloromethane and methanol. The organic phase will be collected, concentrated under vacuum at 40°C, reconstituted in dichloromethane, and transferred to analytical vials.

Metabolomic and lipidomic profiles will be analyzed using liquid chromatography coupled with high-resolution mass spectrometry (LC-MS) and gas chromatography coupled with mass spectrometry (GC-MS). Metabolites and lipids will be identified based on accurate mass, mass spectral data, and comparison with databases and published literature.