ABSTRACT
The biomechanical properties of the tendon are affected due to the changes in composition of the tendon extracellular matrix (ECM). Age, overuse, trauma and metabolic disorders are a few associated conditions that contribute to tendon abnormalities. Hyperlipidemia is one of the leading factors that contribute to the compromised biomechanical. Injury was made on infraspinatus tendon of hyperlipidemic swines. After 8 weeks (i) infraspinatus tendon from the injury site, (ii) infraspinatus tendon from the contralateral side and (iii) Achilles tendon, were collected and analyzed for ECM components that form the major part in biomechanical properties. Immunostaining of infraspinatus tendon on the injury site had higher staining collagen type-1 (COL1A1), biglycan, prolyl 4-hydroxylase and mohawk but lower staining for decorin than the control group. The Achilles tendon of the swines that had injury on infraspinatus tendon showed a chronic adaptation towards load which was evident from a more organized ECM with increased decorin, mohawk and decreased biglycan, scleraxis. The mechanism behind the collagen turnover and chronic adaptation to load need to be studied in detail with the biomechanical properties.
ABSTRACT
Infraspinatus tendon is the most affected tendon of the rotator cuff, being an important posterior component of the shoulder joint. Hyperlipidemia is a predisposing factor in the progression of rotator cuff tears and retear. We studied the effect of hyperlipidemia on the biomechanical properties of rotator cuff tendons. The infraspinatus tendon of the rotator cuff from hyperlipidemic swine were collected and tested for ultimate tensile strength (UTS) and modulus of elasticity. Dynamic mechanical analysis was performed to examine viscoelastic properties. The findings revealed no significant difference in UTS but had significantly lower modulus of elasticity in the infraspinatus tendon of the hyperlipidemic group compared to the control group. Moreover, differences in the dynamic modulus, storage modulus, and loss modulus were not statistically significant between the hyperlipidemic and control swine. There was no difference in water content between the groups but the hyperlipidemic group had fatty infiltration aiding the initial decrease in mechanical properties. These findings suggest an association between fat deposition and early changes in the biomechanical properties of the tendons in the shoulder rotator cuff in hyperlipidemic state.
ABSTRACT
The artificial cultivation of Ganoderma lucidum (MTCC1039) using Artocarpus heterophyllus as sawdust substrate was optimized and free radical scavenging activities of the generated fruiting bodies were investigated. The choice of A. heterophyllus as substrate was due to its easy availability in South India. Sawdust supplemented with dextrose medium yielded better spawn hyphae and early fruiting body initiation (15 days). The biological yield obtained was 42.06 ± 2.14 g/packet and the biological efficiency was 8.41 ± 0.48%. Both aqueous and methanolic extracts of fruiting body were analyzed for radical scavenging activity. Methanolic extract showed maximum scavenging activity for 1,1-diphenyl-2-picrylhydrazyl (IC50 = 290 µg/ml) and 2,2'-azino-bis(3-ethylbenzothiazoline- 6-sulphonic acid (IC50 = 580 µg/ml), whereas aqueous extract had better scavenging for ferric reducing antioxidant power (IC50 = 5 µg/ml). Total phenolic content and total antioxidant capacity were significantly higher in methanolic extract (p < 0.01). A positive correlation existed between the phenolic content and antioxidant activity. Our results indicated that fruiting bodies of G. lucidum cultivated in sawdust medium possess antioxidant property, which can be exploited for therapeutic application.
