Experimental procedure and changes of body and muscle weights during chronic PG-LPS infusion in mice. a PG-LPS was administered once daily for 4 weeks (4w) via intraperitoneal injection (i.p.) at a dose of 0.8 mg/kg in saline. Age-matched control mice (Control) received an identical volume of saline only. PG-LPS; Porphylomonas gingivalis lipopolysaccharide, MA; masseter muscle, TA; tibials anterior muscle, SOL; soleus muscle, CSA; cross-sectional area, b Control and PG-LPS groups showed similar body weight (BW) at 4 weeks after the PG-LPS infusion (P = NS, not significant). c–e Masseter muscle (MA) weight per tibia length (TL) ratio (c) and tibialis anterior muscle weight (TA) per TL ratio (d) were significantly decreased by PG-LPS treatment. Soleus muscle (SOL) weight per TL ratio (e) was similar before and after PG-LPS treatment (*P < 0.05, **P < 0.01 vs control)