The effect of microcurrent therapy on repair of induced tendoninjury in albino rat: possible role of endogenous stem cells

BackgroundTendon repair involves a slow repair process, which results in inferior repair oftissue and failure to obtain full active range of motion. Microcurrent therapy (MCT)is a new therapy after arthroplasty. Stem cells with capacity of self-renewal areideal for tissue engineering.AimThe present work aimed at investigating the effect of MCT and the possible role ofendogenous stem cells in repair of induced tendon injury in albino rat.Materials and methodsTwenty-four male albino rats were classified into: Control group, tenotomy group,5 rats were sacrificed 2 weeks and 5 rats sacrificed 4 weeks following achillistendon injury (Subgroups IIa and IIb respectively). MCT group of 10 rats subjectedto tendon injury followed by MCT, 5 rats sacrificed 2 weeks and 5 rats sacrificed4 weeks following MCT (Subgroups IIIa and IIIb respectively). Tendon sectionswere stained with H E and CD44 and CD105 immunostains. A morphometricstudy was performed.ResultsSubgroup IIa demonstrated multiple areas of widely separated collagen fibers,infiltrating cells and multiple congested vessels. Subgroup I Ib showed multipleareas of disorganized collagen bundles, less infiltrating cells and few congestedvessels. MCT subgroup IIIa revealed some areas of parallel collagen bundles,some infiltrating cells and some dilated congested vessels. MCT subgroupIIIb showed multiple areas of parallel collagen bundles, few infiltrating cellsand occasional congested vessels. CD44 +ve and CD105 +ve cells wereseen among disorganized, parallel collagen fibers and inside blood vessels.A significant increase in the area of regenerated collagen bundles was recordedin MCT subgroup IIIb. The area% of CD44 +ve and CD105 +ve MSCs denoteda significant increase in MCT subgroup IIIa.ConclusionMCT activated endogenous bone marrow derived MSCs migration to theinjured achillis tendon, which stimulated tendon repair following inducedtenotomy.