Protective role of Vaccinium myrtillus's (Bilberry) antioxidant and anti-inflammatory effects in experimental lower limb ischemia-reperfusion injury.

BACKGROUND

Skeletal muscle ischemia-reperfusion (IR) injury is a common clinical problem encountered in vascular and orthopedic surgery, trauma, and transplantation, and is characterized by pronounced oxidative stress and structural tissue damage. Vaccinium myrtillus (bilberry) is rich in anthocyanins and has demonstrated antioxidant and vasoprotective properties in various organ systems; however, its effects on skeletal muscle IR injury have not been previously investigated.

METHODS

Twenty-four male Wistar rats were randomly assigned to four groups (n = 6 per group): Sham (surgical exposure without IR, vehicle-treated), IR (ischemia-reperfusion, vehicle-treated), IR + Vaccinium myrtillus (ischemia-reperfusion treated with bilberry extract, 100 mg/kg intraperitoneally), and Vaccinium myrtillus only (bilberry extract without IR). A standardized commercial bilberry extract (Herbal Liquids, HealthAid®, London, UK) was used. Biochemical analyses included total antioxidant status (TAS), total oxidant status (TOS), oxidative stress index (OSI), and paraoxonase-1 (PON-1) activity. Histopathological evaluation of gastrocnemius muscle tissue was performed using hematoxylin-eosin staining.

RESULTS

Ischemia-reperfusion resulted in significantly higher TOS, OSI, and PON-1 activity and significantly lower TAS levels compared with Sham and bilberry-only groups (p < 0.05). Treatment with Vaccinium myrtillus significantly increased TAS and reduced TOS, OSI, and PON-1 activity compared with the untreated IR group (p < 0.05). Histopathological analysis demonstrated significantly lower scores for muscle fiber degeneration, vascular congestion, nuclear internalization, and leukocyte infiltration in the IR + bilberry group.

CONCLUSIONS

This experimental study provides evidence that Vaccinium myrtillus extract attenuates oxidative stress and reduces histopathological damage in skeletal muscle subjected to ischemia-reperfusion injury. The observed protective effects appear to be primarily related to modulation of redox balance. These findings support further investigation of bilberry as a potential supportive antioxidant strategy in conditions associated with skeletal muscle ischemia-reperfusion injury.