Older people develop a loss a muscle mass and force, which is known as sarcopenia. Changes in the levels of pro-and anti-inflammatory cytokines are seen in serum and tissues of older people, reflecting the development of a chronic inflammation and this is proposed to be one of the major contributors to the development of sarcopenia.Our laboratory has identified significant increases in the pro-inflammatory chemokine, IP10 in the serum of healthy older people (Ford et al, unpublished data). The aim of the current study was to determine the effect of IP10 on indices of atrophy in myotubes in culture.Primary skeletal myoblasts from Wistar rats were isolated, cultured and differentiated into myotubes for 6 days. At this time point, myotubes were treated for either 1,3,5,7 or 10 days with IP10 at the average dose found in serum of older people (200pg/ml) or young adults (150pg/ml). Myotube diameter was assessed. Myotubes treated with IP10 were harvested and qPCR was used to analyse the mRNA expression of the atrophy gene, atrogin1. Values are means ± S.E.M compared by ttest. Treatment of myotubes with 200pg/ml IP10 resulted in a significant increase in relative expression of atrogin1 mRNA (control: n=3, IP10:n=4 p<0.05) 24 hours following treatment and this was accompanied by a significant decrease in myotube diameter (control: 17±0.4 (n=18), IP10:15±0.3 (n=17) p<0.001). This decrease in myotube diameter became more apparent the longer lasting the IP10 treatment. (3 day control: 35±2 (n=10), IP10: 26±0.8 (n=15), 5 day (control: 28±0.8 (n=22), IP10: 23 ± 0.7 (n=27), 7 day control: 28±2 n=15 IP10: 24±0.7 (n=17), 10 day control: 28±2 (n=11), IP10: 18±1 (n=15)p<0.001).Treatment of myotubes for 24 hours with 150pg/ml IP10 resulted in no significant changes to relative expression of atrogin1 mRNA (control:n=3, IP10:n=4 p>0.05) with only a non-significant 2% decrease from control in myotube diameter (control n=18, IP10:n=17 p>0.05) and only a transient reducion in myotube diameter at 3-7 days post-treatment.The increase in atrogin1 and consistent decrease in myotube diameter induced by the levels of IP10 found in older people provides further evidence that an increased inflammatory environment is a likely contributor to sarcopenia. This is in agreement with current knowledge highlighting the importance of the environment on muscle viability and how this mechanism is severely compromised in older people and is a likely contributor to sarcopenia. Future work will examine the effect of nutritional interventions aimed at modifying systemic inflammation and the effects on cytokine-induced muscle atrophy.