Mojgan Mohammadifar1, Mohammad Hossein Aarabi2, Fatemeh Aghighi3, Maryam Kazemi1, Zarichehr Vakili4, Mohammad Reza Memarzadeh5, Sayyed Alireza Talaei6. 1. Biochemistry and Nutrition in Metabolic Diseases Research Center, Institute for Basic Sciences, Kashan University of Medical Sciences, Kashan, Iran. 2. Department of Biochemistry, Faculty of Pharmacy, Isfahan University of Medical Sciences, Isfahan, Iran. 3. Physiology Research Center, Institute for Basic Sciences, Kashan University of Medical Sciences, Kashan, Iran. 4. Department of Pathology, School of Medicine, Kashan University of Medical Sciences, Kashan, Iran. 5. Barij Essence Medicinal Plants Research Center, Kashan, Iran. 6. Physiology Research Center, Institute for Basic Sciences, Kashan University of Medical Sciences, Kashan, Iran. talaei@kaums.ac.ir.
Abstract
BACKGROUND: This study aimed to evaluate the effect of nanoemulsion containing peppermint and rosemary essential oils in rats with osteoarthritis (OA). METHODS: In this experimental study, we prepared a nanoemulsion containing peppermint and rosemary essential oils by spontaneous emulsification and evaluated the nanoemulsion's dermal irritation and toxicity. Investigating the analgesic effect of the nanoemulsion, we randomly assigned 36 male rats to 6 groups: Control (saline injection into the knee), osteoarthritis (intra-articular injection of 2 mg monosodium iodoacetate), and four groups of OA treated with nanoemulsion gel, nanoemulsion solution, rosemary and peppermint essential oil gel, or diclofenac sodium. Treatments were administered topically at a dose of 1 ml daily. Using behavioral tests, we assessed pain on days 1, 4, 7, and 14 after injection. Finally, we did the histopathological and biochemical evaluation of rats' knee joints. RESULTS: There were no irritation signs on the animals' skin after receiving the nanoemulsion and no changes in the hematological and biochemical parameters of rats' blood compared to the control group. Receiving nanoemulsion decreased the mechanical (P < 0.001) and thermal allodynia (P < 0.05), thermal hyperalgesia (P < 0.05), and ambulatory-evoked pain in comparison with the OA group. Also, the nanoemulsion receiving rats showed an increase in SOD and GPx activity and a decrease in MDA level. Histopathology of synovial tissues confirmed the results of behavioral and biochemical tests. CONCLUSION: The nanoemulsion containing essential oils of peppermint and rosemary reduces osteoarthritis pain via increasing antioxidant capacity and improving the histopathological features of the rats' knee joint.
BACKGROUND: This study aimed to evaluate the effect of nanoemulsion containing peppermint and rosemary essential oils in rats with osteoarthritis (OA). METHODS: In this experimental study, we prepared a nanoemulsion containing peppermint and rosemary essential oils by spontaneous emulsification and evaluated the nanoemulsion's dermal irritation and toxicity. Investigating the analgesic effect of the nanoemulsion, we randomly assigned 36 male rats to 6 groups: Control (saline injection into the knee), osteoarthritis (intra-articular injection of 2 mg monosodium iodoacetate), and four groups of OA treated with nanoemulsion gel, nanoemulsion solution, rosemary and peppermintessential oil gel, or diclofenac sodium. Treatments were administered topically at a dose of 1 ml daily. Using behavioral tests, we assessed pain on days 1, 4, 7, and 14 after injection. Finally, we did the histopathological and biochemical evaluation of rats' knee joints. RESULTS: There were no irritation signs on the animals' skin after receiving the nanoemulsion and no changes in the hematological and biochemical parameters of rats' blood compared to the control group. Receiving nanoemulsion decreased the mechanical (P < 0.001) and thermal allodynia (P < 0.05), thermal hyperalgesia (P < 0.05), and ambulatory-evoked pain in comparison with the OA group. Also, the nanoemulsion receiving rats showed an increase in SOD and GPx activity and a decrease in MDA level. Histopathology of synovial tissues confirmed the results of behavioral and biochemical tests. CONCLUSION: The nanoemulsion containing essential oils of peppermint and rosemary reduces osteoarthritis pain via increasing antioxidant capacity and improving the histopathological features of the rats' knee joint.
Authors: Hong-Seng Gan; Tian-Swee Tan; Liang-Xuan Wong; Weng-Kit Tham; Khairil Amir Sayuti; Ahmad Helmy Abdul Karim; Mohammed Rafiq bin Abdul Kadir Journal: Biomed Mater Eng Date: 2014 Impact factor: 1.300