Morphological adaptation of muscle collagen and receptor of advanced glycation end product (RAGE) in osteoarthritis patients with 12 weeks of resistance training: influence of anti-inflammatory or glucosamine treatment.

The aim of this study was to investigate the effect of 12-week resistance training on morphological presence of collagen and RAGE (receptor for advanced glycation end products) in skeletal muscle of patients with knee osteoarthritis (OA). Little is known about the influence of exercise on the skeletal muscle matrix that supports joints affected by OA mainly when it is associated with medication taken by OA patients (non-steroid anti-inflammatory drugs (NSAID) and glucosamine). A biopsy was collected from the vastus lateralis muscle in all patients before and after 12-week period of training. The patients (age 55-69 years) were divided into three groups, treated with NSAID, glucosamine or placebo. In addition, the muscle samples were analysed by immunohistochemistry for collagen types, RAGE and capillaries ratio. An increment in immunoreactivity for type IV collagen after the training period was observed in 72 % of all biopsies when compared with their respective baseline samples. Reduced immunoreactivity of collagen type I was observed in all patients treated with glucosamine. A significant increase with training in the amount of RAGE was detected in the placebo group only (p < 0.05). Comparison of post-treatment states indicated significant differences between the placebo and glucosamine group data, demonstrating increased levels in the placebo group (p < 0.05). These findings suggest a basement membrane remodelling in favour of a strengthened extracellular matrix surrounding individual muscle fibres after 12 weeks of resistance training. Glucosamine with training appeared to attenuate RAGE accumulation more than was seen with NSAID or placebo in skeletal muscle of OA patients.

Nonsteroidal anti-inflammatory drug or glucosamine reduced pain and improved muscle strength with resistance training in a randomized controlled trial of knee osteoarthritis patients.

OBJECTIVES: To investigate the effect of 12 weeks of strength training in combination with a nonsteroidal anti-inflammatory drug (NSAID), glucosamine, or placebo on muscle cross-sectional area (CSA), strength (primary outcome parameters), and function, power, pain, and satellite cell number (secondary outcome parameters) in patients with knee osteoarthritis (OA). DESIGN: Double-blinded, randomized controlled trial. SETTING: Hospital. PARTICIPANTS: Patients (N=36; 20 women, 16 men; age range, 50-70y) with bilateral tibiofemoral knee OA. A total of 181 patients were approached, and 145 were excluded. INTERVENTIONS: Patients were randomly assigned to treatment with the NSAID ibuprofen (n=12), glucosamine (n=12), or placebo (n=12) during 12 weeks of quadriceps muscle strength training. MAIN OUTCOME MEASURES: Muscle CSA and strength. RESULTS: No differences between groups were observed in gains in muscle CSA. Training combined with ibuprofen increased maximal isometric strength by an additional .22Nm/kg (95% confidence interval [CI], .01-.42; P=.04), maximal eccentric muscle strength by .38Nm/kg (95% CI, .05-.70; P=.02), and eccentric muscle work by .27J/kg (95% CI, .01-.53; P=.04) in comparison with placebo. Training combined with glucosamine increased maximal concentric muscle work by an additional .24J/kg versus placebo (95% CI, .06-.42; P=.01). CONCLUSIONS: In patients with knee OA, NSAID or glucosamine administration during a 12-week strength-training program did not improve muscle mass gain, but improved maximal muscle strength gain in comparison with treatment with placebo. However, we do not find that the benefits are large enough to justify taking NSAIDs or glucosamine.

Ethinyl oestradiol administration in women suppresses synthesis of collagen in tendon in response to exercise.

Women are at greater risk than men of sustaining certain kinds of injury and diseases of collagen-rich tissues. To determine whether a high level of oestradiol has an acute influence on collagen synthesis in tendons at rest and in response to exercise, one-legged kicking exercise was performed for 60 min at 67% of maximum power by healthy, young oral contraceptive (OC) users when circulating synthetic (ethinyl) oestradiol was high (n = 11, HE-OC) and compared to similar women who had never used OCs when circulating endogenous oestrogen was low (n = 12, LE-NOC). Interstitial fluid was collected 24 h post-exercise through microdialysis catheters placed anterior to the patellar tendon in both legs and subsequently analysed for the amino-terminal propeptide of type I collagen (PINP), a marker of tendon collagen synthesis. To determine the long-term effect of OC usage, patellar tendon cross-sectional area (CSA) was measured by magnetic resonance imaging (MRI). A lower exercise-induced increase in tendon collagen synthesis was observed in HE-OC than in LE-NOC (DeltaPINP (mean +/- s.e.m.) 1.5 +/- 5.3 versus 24.2 +/- 9.4 ng ml(-1), P < 0.05). Furthermore, serum and the interstitial peritendinous tissue concentrations of insulin-like growth factor I (IGF-I) and IGF-binding proteins showed a reduced bioavailability in HE-OC compared with results in LE-NOC. No difference in patellar tendon CSA was observed between groups. In conclusion, the selective increase in tendon collagen synthesis in LE-NOC but not HE-OC 24 h post-exercise is consistent with the hypothesis that oestradiol inhibits exercise-induced collagen synthesis in human tendon. The mechanism behind this is either a direct effect of oestradiol, or an indirect effect via a reduction in levels of free IGF-I. However, the data did not indicate any long-term effect on tendon size associated with chronic OC use.