The purpose of this study was to examine the effects of Cu/Zn SOD on reduction of hindlimb muscular atrophy induced by cisplatin in rats.

Forty-two rats were assigned to three groups; control group, Cisplatin (CDDP) group and cisplatin with Cu/Zn SOD (CDDP-SOD) group. At day 35 hindlimb muscles were dissected. Food intake, activity, withdrawal threshold, muscle weight, and Type I, II fiber cross-sectional area (CSA) of dissected muscles were measured. Relative SOD activity and expression of MHC and phosphorylated Akt, ERK were measured after dissection.

Muscle weight and Type I, II fiber CSA of hindlimb muscles in the CDDP group were significantly less than the control group. Muscle weight and Type I, II fiber CSA of hindlimb muscles, food intake, activity, and withdrawal thresholds of the CDDP-SOD group were significantly greater than the CDDP group. There were no significant differences in relative SOD activities of hindlimb muscles between the CDDP-SOD and CDDP groups. MHC expression and phosphorylated Akt, ERK of hindlimb muscles in the CDDP-SOD group were significantly greater than the CDDP group.

Cu/Zn SOD attenuates hindlimb muscular atrophy induced by cisplatin through increased food intake and activity. Increment of phosphorylated Akt, ERK may relate to attenuation of hindlimb muscular atrophy.

The purpose of this study was to examine the effect of anorexia and neuropathic pain induced by cisplatin on hindlimb muscles of rats.

Adult male Sprague-Dawley rats were divided into two groups, a cisplatin-treated group (n=10) and a control group (n=10). In the cisplatin-treated group, cisplatin at a dose of 2 mg/kg was injected intraperitoneally two times a week up to a cumulative dose of 20 mg/kg over 5 weeks, and in the control group saline (0.9% NaCl) was injected intraperitoneally at the same dose and duration as the cisplatin-treated group. At 34 days all rats were anesthetized, after which the soleus and plantaris muscles were dissected. Withdrawal threshold, body weight, food intake, activity, muscle weight, Type I and II fiber cross-sectional areas and myofibrillar protein content of the dissected muscles were determined.

Compared with the control group, the cisplatin-treated group showed significant decreases (p<.05) in withdrawal threshold, activity, food intake, body weight, Type I and II fiber cross-sectional areas, myofibrillar protein content and weight of the soleus and plantaris muscles.

Muscular atrophy in hindlimb occurs due to anorexia and neuropathic pain induced by the cisplatin treatment.

The purpose of this study was to determine the effect of dehydroepiandrosterone (DHEA) on recovery of muscle atrophy induced by Parkinson's disease.

The rat model was established by direct injection of 6-hydroxydopamine (6-OHDA, 20 µg) into the left striatum using stereotaxic surgery. Rats were divided into two groups; the Parkinson's disease group with vehicle treatment (Vehicle; n=12) or DHEA treatment group (DHEA; n=22). DHEA or vehicle was administrated intraperitoneally daily at a dose of 0.34 mmol/kg for 21 days. At 22-days after DHEA treatment, soleus, plantaris, and striatum were dissected.

The DHEA group showed significant increase (p<.01) in the number of tyrosine hydroxylase (TH) positive neurons in the lesioned side substantia nigra compared to the vehicle group. Weights and Type I fiber cross-sectional areas of the contralateral soleus of the DHEA group were significantly greater than those of the vehicle group (p=.02, p=.00). Moreover, extracellular signal-regulated kinase (ERK) phosphorylation significantly decreased in the lesioned striatum, but was recovered with DHEA and also in the contralateral soleus muscle, Akt and ERK phosphorylation recovered significantly and the expression level of myosin heavy chain also recovered by DHEA treatment.

Our results suggest that DHEA treatment recovers Parkinson's disease induced contralateral soleus muscle atrophy through Akt and ERK phosphorylation.

The purpose of this study was to examine effects of nitric oxide synthase (NOS) inhibitor on muscle weight and myofibrillar protein content of affected and unaffected hindlimb muscles in rats with neuropathic pain induced by unilateral peripheral nerve injury.

Neuropathic pain was induced by ligation and cutting of the left L5 spinal nerve. Adult male Sprague-Dawley rats were randomly assigned to one of two groups: The NOSI group (n=19) had NOS inhibitor (L-NAME) injections daily for 14 days, and the Vehicle group (n=20) had vehicle injections daily for 14 days. Withdrawal threshold, body weight, food intake and activity were measured every day. At 15 days all rats were anesthetized and soleus, plantaris and gastrocnemius muscles were dissected from hindlimbs. Muscle weight and myofibrillar protein content of the dissected muscles were determined.

The NOSI group showed significant increases as compared to the Vehicle group for body weight at 15 days, muscle weight and myofibrillar protein content of the unaffected soleus and gastrocnemius. The NOSI group demonstrated a higher pain threshold than the vehicle group.

NOSI for 14 days attenuates unaffected soleus and gastrocnemius muscle atrophy in neuropathic pain model.

The purpose of this study was to examine the effects of exercise on muscle weight and Type I and II fiber cross-sectional area of affected and unaffected hindlimb muscles in rats with neuropathic pain induced by unilateral peripheral nerve injury.

Neuropathic pain was induced by ligation and cutting of the left L5 spinal nerve. Adult male Sprague-Dawley rats were randomly assigned to one of two groups: The Pain+Exercise (PE) group (n=21) and the Sham+Exercise (SE) group (n=20). All rats had 28 sessions of treadmill exercise at grade 10 for 30 minutes, twice/day at 10 m/min for 14 days. Body weight, food intake and activity were measured every day. At 15 days all rats were anesthetized and soleus, plantaris and gastrocnemius muscles were dissected. Muscle weight and Type I, II fiber cross-sectional area of the dissected muscles were measured.

The PE group showed significant increases (p<.05), as compared to the SE group for body weight and total diet intake, muscle weight of the unaffected soleus and plantaris, and in Type I and II fiber cross-sectional area of unaffected three muscles and affected plantaris.

Exercise for 14 days attenuates unaffected soleus, plantaris and gastrocnemius muscle atrophy in neuropathic pain model.

The purpose of this study was to examine the effect of DHEA (Dehydroepiandrosterone) on muscle weight and Type I and II fiber cross-sectional area of affected and unaffected hindlimb muscles in rats with neuropathic pain induced by unilateral peripheral nerve injury.

Neuropathic pain was induced by ligation and cutting of the left L5 spinal nerve. Adult male Sprague-Dawley rats were randomly assigned to one of two groups: The DHEA group (n=10) had DHEA injections daily for 14 days, and the Vehicle group (n=10) had vehicle injections daily for 14 days. Withdrawal threshold, body weight, food intake and activity were measured every day. At 15 days all rats were anesthetized and soleus, plantaris and gastrocnemius muscles were dissected from the both hindlimbs. Body weight, food intake, activity, muscle weight and Type I, II fiber cross-sectional area of the dissected muscles were measured.

The DHEA group showed significant increases (p<.05), as compared to the vehicle group for muscle weight of the unaffected plantaris, and in Type II fiber cross-sectional area of the gastrocnemius muscle. The DHEA group demonstrated a higher pain threshold than the vehicle group whereas total diet intake and activity score were not significantly different between the two groups.

DHEA administration for 14 days attenuates unaffected plantaris and gastrocnemius muscle atrophy.

The purpose of this study was to examine the effects of unilateral sciatic nerve injury on unaffected hindlimb muscles of rats.

Adult male Sprague-Dawley rats were assigned to one of three groups: control (C) group (n=10) that had no procedures, sham (S) group (n=10) that underwent sham left sciatic nerve transection, and sciatic nerve transection (SNT) group (n=9) that underwent left sciatic nerve transection. At 15 days rats were anesthetized, and the soleus, plantaris and gastrocnemius muscles were dissected.

Muscle weight of the unaffected plantaris muscle in the SNT group was significantly lower than in the other two groups. Type II fiber cross-sectional areas of the unaffected plantaris and gastrocnemius muscles in the SNT group were significantly smaller than in the other two groups. The decrease of muscle weights and Type I, II fiber cross-sectional areas of the unaffected three muscles in the SNT group were significantly less than that of the affected three muscles.

Hindlimb muscle atrophy occurs in the unaffected side after unilateral sciatic nerve injury, with changes in the plantaris and gastrocnemius muscle being more apparent than changes in the soleus muscle. These results have implications for nursing care, in the need to assess degree of muscle atrophy in unaffected muscles as well as affected muscles.

The purpose of this study was to determine the effect of Dehydroepiandrosterone (DHEA) administration alone or exercise combined with DHEA before steroid treatment on rat hindlimb muscles.

Male Sprague-Dawley rats were assigned to one of three groups: a steroid group (S, n=10) that had no treatment for 7 days before steroid treatment; a DHEA-steroid group (DS, n=8) that had 0.34 mmol/kg/day DHEA injection once a day for 7 days before steroid treatment and an exercise+DHEA-steroid group (EDS, n=9) that ran on the treadmill combined with 0.34 mmol/kg/day DHEA injection for 7 days before steroid treatment. At 15 days all rats were anesthetized and soleus, plantaris and gastrocnemius muscles were dissected. Body weight, food intake, muscle weight, myofibillar protein content and cross-sectional area of the dissected muscles were determined.

The DS group showed significant increases (p<.05) as compared to the steroid group in body weight, and muscle weight of gastrocnemius muscles. The EDS group showed significant increases (p<.05) as compared to the S group in body weight, muscle weight, myofibrillar protein content, and Type II fiber cross-sectional area of soleus, plantaris and gastrocnemius muscles.

Exercise combined with DHEA administration before steroid treatment prevents steroid induced muscle atrophy, with exercise combined with DHEA administration being more effective than DHEA administration alone in preventing muscle atrophy.

The purpose of this study was to identify muscle atrophy in critically ill patients on ventilators. A comparison was made between limb circumferences and muscle areas on the day of admission to an intensive care unit (ICU) and on the 8th day after admission.

The data were collected from 30 critically ill patients using ventilators at S hospital ICU in Seoul during the period from October 2005 to April 2006. Limb circumferences and skinfold thickness were measured on the day of admission and on the 8th day after admission to the ICU. Limb circumferences and skinfold thickness were measured on the right mid-arm, right mid-thigh, and right mid-calf using a measuring tape and a skinfold calipers. Limb muscle areas were calculated by an equation after measuring limb circumferences and skinfold thickness. The data were analyzed by paired t-test and independent t-test.

1) Mid-arm circumference, mid-thigh circumference and mid-calf circumference on the 8th day after admission to the ICU were significantly less than those on the day of admission to the ICU, 2) Mid-arm muscle area, mid-thigh muscle area and mid-calf muscle area on the 8th day after admission to the ICU were significantly less than those on the day of admission to the ICU, 3) Steroid and vecuronium medication didn't affect changes in limb circumferences (mid-arm, mid-thigh, mid-calf) and muscle areas (mid-arm, mid-thigh, mid-calf) on the 8th day after admission to the ICU compared to the day of admission.

Limb muscle atrophy may occur on the 8th day after admission to the ICU in critically ill patients using ventilator.

The purpose of this study was to examine the effects of daily exercise before steroid treatment on mass, the type I and II fiber cross-sectional area, and myofibrillar protein content of hindlimb muscles in a rat model.

Adult male Sprague-Dawley rats were randomly assigned to one of three groups: a control group(n=10) that had a normal saline injection for 7days, a steroid group(n=10) that had a steroid injection for 7days, and an exercise-steroid group(n=10) that ran on the treadmill for 7days before a steroid treatment. Body weight and food intake were measured every day. At 15 days all rats were anesthetized and the soleus, plantaris and gastrocnemius muscles were dissected.

The exercise-steroid group showed significant increases as compared with the steroid group in body weight, muscle weight of the soleus and gastrocnemius, type II muscle fiber cross-sectional area of plantaris, and myofibrillar protein content of the soleus, plantaris, and gastrocnemius. As compared with the control group, the steroid group showed significant decreases in body weight and diet intake, muscle weight, the type II fiber cross-sectional area and myofibrillar protein content of the soleus, plantaris, and gastrocnemius muscles.

Daily exercise before steroid treatment attenuates hindlimb muscle atrophy, with type II muscle changes more apparent than type I muscle changes.