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A proteomic approach was used to identify proteins differentially expressed in the plasma of mice following alternate day fasting. Male mice (C57Bl6, 9 months old) were randomly assigned to ad libitum (AL, n = 10) and calorie-restricted (IF, n = 10, AL on alternate day basis) groups for 4 weeks. After staining, the gels were imaged and differential protein expression patterns were interrogated using image analysis software. Spots showing a different expression level were identified through a comparison with 2D maps found in databases officially recognized (ExPASy). Master gels of AL and IF mice exhibited slightly different 2-DE patterns as only 14 spots out of 500 appeared differentially expressed: 12 spots were downregulated and identified as apolipoprotein E (APO-E), haptoglobin (HPT), alpha-1-antitrypsin (A1AT), pro- thrombin, and serum amyloid P component (SPA), whereas two spots were unidentified. In conclusion 4 weeks of alternate feeding results in a slight perturbation of the host plasma proteome. Of particular interest is the reduced plasma content in APO-E and acute-phase proteins HPT, A1AT and SPA that confirms a powerful anti-inflammatory effect of this dietary regimen.

Introduction: Myopathy is the most common side effect of statins. Because nitric oxide (NO) has a key role in regulating skeletal muscle function, we studied whether the NO-donating atorvastatin NCX 6560 could show a better profile on skeletal muscle function and structure compared with ator- vastatin. Methods: C57BL/6 mice received atorvastatin 40 mg/ kg/day or an equivalent dose of NCX 6560 for 2 months. Mus- cle function assessed by treadmill test, serum creatine kinase (CK) activity, citrate synthase (CS) activity, and muscle histol- ogy were evaluated. Results: Atorvastatin significantly (P < 0.001) reduced muscle endurance, increased serum CK by 6- fold, and induced muscle fiber atrophy. Conversely, NCX 6560 preserved muscle function, prevented CK increase and did not modify muscle structure. Interestingly, atorvastatin reduced CS activity, a marker for mitochondrial function, in gastrocnemius, diaphragm, and heart, whereas NCX 6560 prevented such decrease. Conclusions: These findings suggest that NO may prevent statin-induced myopathy. Muscle Nerve 47: 72-80, 2013

Using an in vitro assay we assessed whether the acute exposure of soleus muscle of adult and aged rats to essential amino acid enriched mixture (EAAem) activates mTOR signaling pathway (mTOR and p70S6K) even after prolonged supplementation with the same mixture. A total of 20 adult (9 months of age at the end of treatment) and 20 aged (18 months of age at the end of treatment) male Wistar rats were used. Ten of each group were treated with EAAem (1.5 gr/kg/day in tap water) for 6 months. At the end of treatment the rats were grouped (n = 5 each group) as follows: adult (AD) and aged (AG) untreated controls; adult (AD_EAAem) and aged (AG_EAAem) chronically supplemented with EAAem; adult (AD+EAAem) and aged (AG+EAAem) acutely incubated with EAAem (soleus in 1 percent EAAem for 30 min); AD_EAAem+ and AG_EAAem+ acutely incubated with EAAem. Following treatment the activation level of mTOR and p70S6K was measured by Western blot. The basal level of mTOR and p70S6K activation appeared to be higher in AD compared with AG. In AG+EAAem a significant change in the level of p70S6K activation, unlike mTOR, was observed whereas no change was observed in AD+EAAem. In AD_EAAem muscles the basal level of p70S6K activation, unlike mTOR, was significantly lower than in AD and the acute exposure to EAAem produced a significant reduction of mTOR activation. Contrarily to AG, in AG_EAAem+ the acute exposure to EAAem produced a significant activation of mTOR, unlike p70S6K. Results in the adults indicated a higher basal level of activation and a lower responsiveness of the pathway to acute and chronic exposure to EAA-enriched mixture. On the contrary, in the aged, a lower basal level of activation was associated with a higher responsiveness to EAAem. In particular, although with a different timing, acute exposure to EAAem activated mTOR signaling even following prolonged supplementation.