Effects of different concentrations of hypertonic glucose in the repair of tendon injury in rats

Zhou Lina; Li Yun; Liu Xixia

doi:10.12307/2025.942

Abstract：BACKGROUND:Numerous clinical trials have demonstrated that hypertonic glucose prolotherapy promotes tendon injury healing,yet the underlying mechanisms remain unclear. OBJECTIVE:To investigate the effects of different concentrations of hypertonic glucose on rat behavior,cellular morphology,tendon extracellular matrix components,and growth factors. METHODS:Fifty male Sprague-Dawley rats were randomly assigned into five groups:control blank,model,5%glucose,15%glucose,and 25%glucose groups,with 10 rats in each group.(1)Modeling:Except for the control blank group,all groups received an Achilles tendon injection of type I collagenase.(2)Intervention:The control blank and model groups received no treatment.The 5%,15%,and 25%glucose groups received injections of 30 µL of 5%,15%,and 25%glucose,respectively,into the right Achilles tendon once a week for 3 weeks.(3)Assessments:Behavioral assessments,hematoxylin-eosin staining,western blot,and RT-qPCR were conducted to assess type I collagen,type III collagen,transforming growth factor β1,vascular endothelial growth factor,and SCX expression levels in tendon tissue. RESULTS AND CONCLUSION:(1)Behavioral analysis:Compared with the control blank group,the model group showed a significant reduction in 5-minute running distance(P<0.05).Compared with the model group,the 25%glucose group exhibited a significant increase in 5-minute running distance(P<0.05).(2)Compared with the control blank group,tendon tissue in the other groups showed varying degrees of collagen disarray,increased number of blood vessels,and increased number of cells.However,glucose-treated groups exhibited more orderly collagen alignment than the model group.(3)Compared with the control blank group,the mRNA expression of type I collagen α1 was reduced,and the mRNA expression of type III collagen was increased in the model group(P<0.05).Compared with the model group,the 25%glucose group exhibited increased mRNA expression of type I collagen α1,while both the 15%and 25%glucose groups showed significantly decreased mRNA expression of type III collagen and increased SCX mRNA expression(P<0.05).(4)Compared with the control group,the model group displayed reduced protein expression of type I collagen and increased protein expression of type III collagen and vascular endothelial growth factor(P<0.05).Compared with the model group,the glucose intervention groups had decreased protein expression of type III collagen,with the 25%glucose group showing increased protein expression of type I collagen and the 15%glucose group exhibiting elevated protein expression of vascular endothelial growth factor and transforming growth factor β1(P<0.05).To conclude,hypertonic glucose promotes vascular endothelial growth factor and transforming growth factor β1 expression,modulates collagen synthesis,increases the content of type I collagen,and accelerates tendon healing.Furthermore,25%hypertonic glucose concentration has the optimal intervention effect.