Drinking A High Fructose Corn Syrup-like Sports Drink Does Not Worsen AKI Risk During Simulated Occupational Heat Stress

Introduction Drinking high fructose corn syrup (HFCS) sweetened soft drinks worsens acute kidney injury (AKI) risk during simulated occupational heat stress (OHS). Some sports drinks are sweetened with HFCS, but these drinks contain less sugar than soft drinks (0.056 vs. 0.128 g/mL). We tested the hypothesis that OHS-induced AKI risk will be greater when drinking a HFCS-like vs. a sucrose-sweetened sports drink. Methods In this randomized double-blind crossover study, 12 healthy adults (26±7 y; 6 women) completed two trials involving ingestion of six 500 mL doses of a HFCS-like (55% fructose & 45% glucose) or a sucrose-sweetened (SS) sports drink before, during, and following a 4 h simulated OHS involving three circuits of 10 min of treadmill walking, 5 min of rowing (5 METS), and 15 min of rest per hour. Drinks were matched for taste, total sugar (28 g), and electrolytes (Na + : 210 mg; K + : 65 mg) and were closely matched for osmolality (HFCS: 337 ± 6 mOsm/L; SS: 204 ± 2 mOsm/L). Urine and blood samples were collected pre-, post-, 60 min after post- (recovery), and 24 h post-visit. AKI risk was quantified as the product of urine insulin-like growth factor-binding protein 7 and urine tissue inhibitor of metalloproteinase 2 ([IGFBP7•TIMP-2]). Inflammatory (monocyte chemotactic protein-1, MCP-1) and oxidative stress (thioredoxin 1, TRX-1) proteins were measured, with increased fractional excretion (FE) indicating renal origin. Results Peak rectal temperature (HFCS: 38.3±0.7°C, SS: 38.3±0.7°C, p=0.991) and percent changes in body weight (HFCS: -0.6±1.0%, SS: -0.9±0.8%, p=0.469) were not different between trials. [IGFBP7•TIMP-2] increased over time (p<0.001) but did not differ between trials [peak change (Δ) - HFCS: 1.8±0.1, SS: 1.6±1.7 (ng/mL) 2 /1000, p=0.677]. Serum MCP-1 increased over time (p<0.001) and the peak Δ was higher in the HFCS trial (0.21±0.21 vs. 0.13±0.13 ng/mL, p=0.052). Serum TRX-1 did not differ over time (p=0.087) but the peak Δ was higher in the HFCS trial (14.7±12.3 vs. 4.9±11.3 ng/mL, p=0.032). FE MCP-1 increased over time (p=0.005) but did not differ between trials (peak Δ - HFCS: -0.4±0.6%, SS: 0.4±2.1%, p=0.519). FE TRX-1 increased over time (p=0.002) and the peak Δ was lower in the HFCS trial (-2.7±5.6% vs. 3.9±8.7%, p=0.005).Peak Δ in [IGFBP7•TIMP-2] was not correlated with peak Δ in FE TRX-1 (r=-0.037, p=0.865), FE MCP-1 (r=-0.216, p=0.312), or serum TRX-1 (r=0.154, p=0.473) but was positively correlated with the peak Δ in serum MCP-1 (r=0.571, p=0.004). Conclusion Drinking a HFCS-like sports drink aggravated systemic inflammation and oxidative stress, but not AKI risk. The correlation between [IGFBP7•TIMP-2] and serum MCP-1 suggest a role of systemic inflammation in OHS-induced AKI risk. Support: R01OH011528 This abstract was presented at the American Physiology Summit 2025 and is only available in HTML format. There is no downloadable file or PDF version. The Physiology editorial board was not involved in the peer review process.