Fructose-Induced Impairment of Liver and Skeletal Muscle Metabolism Is Prevented by Administration of Shouchella clausii Spores by Preserving Mitochondrial Function and Insulin Sensitivity.

The objective of the study was to evaluate the efficacy of S. clausii spores (SF174) in counteracting the deleterious effects of dietary fructose. Thirty-days old male Wistar rats were treated for 6 weeks: control group: 0.5 mL of 10% sucrose solution (without probiotics); fructose group: 0.5 mL of 10% sucrose solution + high-fructose diet (without probiotics); SF174 group: 0.5 mL of 10% sucrose solution containing SF174 (5 × 10⁹ CFU) + high-fructose diet. Fructose intake induced an increase in proinflammatory cytokines in portal plasma, liver, and skeletal muscle, a decrease in insulin sensitivity in both tissues and a condition of hepatic steatosis. An increase in the mitochondrial activity in the liver and a decrease in skeletal muscle were evidenced, together with an increase in the thiobarbituric acid reactive substances (TBARS) levels and a decrease in the antioxidant enzyme activity. All the above alterations were counteracted by probiotic administration. We here demonstrate for the first time that S. clausii SF174 counteracts low-grade inflammation and insulin resistance induced by fructose, protects mitochondria from changes in oxidative capacity, and maintains unaltered the oxidative balance. Therefore, S. clausii SF174 administration can be an effective strategy to prevent the unhealthy consequences of dietary fructose.