Background: Submandibular gland impairment is a common side effect of methotrexate (MTX). L-carnitine (LC) is an antioxidant that is widely used nowadays as a protective against chemotherapeutic drugs' hazards.
Aim of the work: examine the potential protective effect of LC on MTX induced submandibular gland injury.
Material and methods: Thirty-six adult male albino rats, aging 4-6 months and weighing 200-250 gm, were used. Animals were divided into three groups. Group I: control group and was further subdivided into four subgroups 6 rats each. Group II: included 6 rats which received 20mg/kg MTX intraperitoneally on the first day. Group III: included 6 rats which received 20mg/kg MTX intraperitoneally on the first day and oral 100 mg/kg LC once daily from first till fifth day. After 5 days, animals were anesthetized, and submandibular glands were excised and processed for histological, ultrastructural, immunohistochemical and morphometric studies.
Results: Methotrexate induced marked distortion and separation of the gland's histoarchitecture with congestion, connective tissue fibers' aggregation and cellular infiltration. Ultra structurally, acinar and striated ductal cells revealed degenerative nuclear changes, marked cytoplasmic vacuolation and indistinct organelles. Morphometric analysis revealed highly significant decrease in Ki-67 immune stain. However, rats given LC with MTX had marked preservation of glandular histoarchitecture and significant increase in Ki-67 immune expression.
Conclusion: L-carnitine exerted a marked protective role against MTX induced submandibular histoarchitectural changes. Thus, it could be considered as a highly promising protective agent against MTX-induced xerostomia in cancer and RA arthritis patients.