Light and electron microscopic study on the effect of training and high cholesterol diet on the skeletal muscle of male albino rat exposed to strenuous exercise

The present study aimed at investigating the effect of training and high cholesterol diet on the skeletal muscle [soleus] of male albino rat exposed to strenuous exercise [SE] immediately and 24 hours after. Eighty eight male albino rats were divided into 2 groups: group 1 given balanced diet and group 2 given high cholesterol diet. Each group was subdivided into control rats not subjected to exercise and experimental group which included untrained and trained rats exposed to [SE] and sacrificed immediately or after 24 hours. Serum triglyceride [TG] and low density lipoprotein cholesterol [LDL-C] were tested. Semithin and ultrathin sections were examined by light and electron microscopes. Mean unclear area and count of sarcoplasmic vacuoles were assessed morphometrically. In group 1, nuclei with peripheral chromatin condensation, darkly stained fibers and electron dense areas were seen in untrained rats immediately following [SE]. Small nuclei with peripheral chromatin condensation, atypically arranged myofibrils, discontinuous A bands, focal loss of Z lines with electron dense particles around and enlarged,mitochondria with destroyed cristae were detected in untrained rat muscles 24 hours following [SE]. Less changes were noticed in corresponding trained rats. Group 2 revealed multiple sarcoplasmic vacuolations. Dark areas, irregular discontinuous myofibrils and small nuclei with peripheral chromatin condensation appeared in untrained rat muscle immediately following [SE]. In addition, small dark nuclei existed 24 hours after [SE]. Highly significant decrease in mean nuclear area and mean count of sarcoplasmic vacuoles existed in untrained and trained subgroups respectively. Dilated cisternae of sarcoplasmic reticulum, enlarged mitochondria with destroyed cristae and irregular focally disrupted sarcolemma were seen in untrained rats. Less changes were detected in corresponding trained rats. Serum [LDL-C] and [TG] showed highly significant increase in group 2 and highly significant decrease in trained subgroups. It was concluded that apoptosis was induced by strenuous exercise exacerbated by hypercholesterolemia and lessened by training

modulatory effect of some antioxidants on hepatocytes of adriamycin treated rats: light and electron microscopy study

Adriamycin [ADR] is one of an anthracycline group. It is used as an effective chemotherapeutic agent in treatment of many human tumors. However, its clinical use has been limited because of its severe toxicity to the heart, liver, kidney, stomach, intestine and bone marrow. On the other hand, L-carnitine and b-carotene have high antioxidative properties. This study was an attempt to evaluate the possible protective effect of L-carnitine and b- carotene against the [ADR] induced hepatotoxicity. Thirty six adult male albino rats weighing 150 +/- 180 gm were divided into four groups. Group I: the control group. Group II: each rat received four equal intraperitoneal injections of ADR [each containing 2.5 mg/kg] over two weeks. Group III: each rat received ADR plus daily oral intake of 200 mg/kg of L-carnitine and group IV: which was given ADR plus daily oral intake of 30 mg/kg of B- carotene. One day after the last dose all animals were sacrificed and their livers were dissected. Liver specimens were prepared for both light and electron microscopy. At light microscopic level, paraffin sections were subjected to Hx and E., Feulgen reaction for DNA and bromophenol reaction for total protein contents. Light microscopic examination of group II rats revealed loss of normal hepatic architecture. Most hepatocytes showed vacuolated cytoplasm. Pyknotic, fragmented, ghost and totally absent nuclei were also observed. Many necrotic cells were present. Significant decrease in nucleic acid and total protein contents was found as a result of [ADR] treatment. At the ultrastructural level, the hepatocytes exhibited nuclear chromatin condensation, swelling of the mitochondria with destructed cristae. Massive dilatation of rER and sER and Golgi apparatus was also noticed. Many electron dense cytoplasmic bodies suggested to be lysosomal elements were found. On the other hand, animal groups treated with L- carnitine and b- carotene exhibited that most of hepatocytes were apparently normal with minimal cytoplasmic vacuolation. Marked improvement in the DNA and total protein contents. Ultrastructurally, mitochondria were slightly destroyed Minimal rER, sER, and Golgi dilatation and there was homogenous nuclear chromatin distribution. Thus, L-carnitine and b- carotene could ameliorate ADR hepatic alterations and their supplementation is recommended for cancer patients treated with [ADR]