The possible role of L-carnitine on the skeletal muscle of ovariectomized rats

Low muscle strength is observed during the peri-and postmenopausal periods, when the secretion of ovarian hormones is drastically reduced. It is also a predictive of adverse health events as well as incident mobility limitation and disability. The objective of the present study is to study the biochemical and the histological changes in the skeletal muscle of premature menopause-induced rats and the possible protective role of L-carnitine. Ovariectomized (OVX) rats were gavaged with L-carnitine (100 mg/kg) daily for 60 days starting from the second post-operative day. Serum levels of estradiol and markers of skeletal muscle damage (creatine kinase and lactic dehydrogenase activities) were determined. Light and electron microscopic study of the quadriceps femoris muscle (QFM) specimens were done. OVX rats showed significant decrease in the serum estradiol level with significant increase the markers for skeletal muscle damage. Histopathological examination of the QFM showed degenerated myofibers, apoptotic changes and compensatory hypertrophy. Degenerated mitochondria, multiple lysosomes and lipid droplets among the damaged myofibrils were also noticed. L-carnitine administration to the OVX rats resulted in non-significant change in the serum estradiol level with significant attenuation of skeletal muscle damage either biochemically or histopathologically. In conclusion, L-carnitine administration recovered muscle degeneration after ovariectomy. This finding suggested that L-carnitine could be recommended in the management of post-menopausal myopathy.     

Bacillus amyloliquefaciens BSL16 improves phytoremediation potential of Solanum lycopersicum during copper stress

Current study aimed at exploring the diversity of bacterial endophytes with Boswellia sacra and their role in copper (Cu) stress to tomato plants. Bacterial endophytes were belonged to Bacillus, Rhizobium and Paenibacillus, which were screened against Cu (0–10?mM) stress to dwarf and normal rice seeds. Among strains, Bacillus amyloliquefaciens BSL16 showed significantly higher bioremediation potential by accumulating high Cu and promoting growth of rice seeds. B. amyloliquefaciens BSL16 significantly increased growth of tomato plants during 2.5?mM Cu stress. Active colonization of BSL16 reduced the accumulation of Cu in leaf, shoot, and root, and in parallel up-regulated total protein contents in leaf and stem. Glutathione peroxidase and reduced glutathione contents were significantly higher and lipid peroxidation was lower in endophyte-treated tomato plants as compared to Cu treatment. The current results conclude that application of metal bio-accumulating bacteria can help in improving the plant growth of tomato plants during Cu stress.     

Effect of celecoxib on the antihypertensive effect of losartan in a rat model of renovascular hypertension

Certain nonsteroidal anti-inflammatory drugs have been reported to elevate blood pressure in some hypertensive patients, who are either untreated or treated with antihypertensive agents. This study was undertaken to determine the effect of a selective cyclooxygenase-2 (COX-2) inhibitor, celecoxib, on the antihypertensive effects of the angiotensin II type 1 receptor (AT1) antagonist, losartan potassium. We studied the effect of oral treatment with losartan (30?mg/kg), celecoxib (3?mg/kg), and their combination on the mean arterial blood pressure (MAP), plasma renin activity (PRA), and plasma prostaglandin E2 (PGE2) in male Sprague-Dawley rats with renovascular hypertension (RVH) induced by partial subdiaphragmatic aortic constriction. Treatment was continued for 7 days after aortic coarctation. Aortic coarctation led to significant increases in the MAP, PRA, and plasma PGE2. In RVH rats, losartan treatment caused a significant decrease of MAP with a significant increase in both plasma PGE2 and PRA. Celecoxib caused a nonsignificant change in MAP with a significant decrease in the raised levels of plasma PGE2 and PRA. Concomitant administration of celecoxib and losartan did not significantly affect the lowering effect of losartan on MAP with a subsequent significant decrease in the plasma PGE2 and PRA in RVH rats. Therefore, celecoxib could be used in renin-dependent hypertensive patients who receive losartan, without fear of a rise in their blood pressure.     

Prediabetes Phenotype Influences Improvements in Glucose Homeostasis with Resistance Training

Purpose

To determine if prediabetes phenotype influences improvements in glucose homeostasis with resistance training (RT).

Methods

Older, overweight individuals with prediabetes (n = 159; aged 60±5 yrs; BMI 33±4 kg/m²) completed a supervised RT program twice per week for 12 weeks. Body weight and composition, strength, fasting plasma glucose, 2-hr oral glucose tolerance, and Matsuda-Defronza estimated insulin sensitivity index (ISI) were assessed before and after the intervention. Participants were categorized according to their baseline prediabetes phenotype as impaired fasting glucose only (IFG) (n = 73), impaired glucose tolerance only (IGT) (n = 21), or combined IFG and IGT (IFG/IGT) (n = 65).

Results

Chest press and leg press strength increased 27% and 18%, respectively, following the 12-week RT program (both p<0.05). Waist circumference (-1.0%; pre 109.3±10.3 cm, post 108.2±10.6 cm) and body fat (-0.6%; pre 43.7±6.8%, post 43.1±6.8%) declined, and lean body mass (+1.3%; pre 52.0±10.4 kg, post 52.7±10.7 kg) increased following the intervention. Fasting glucose concentrations did not change (p>0.05) following the intervention. However, 2-hr oral glucose tolerance improved in those with IGT (pre 8.94±0.72 mmol/l, post 7.83±1.11 mmol/l, p<0.05) and IFG/IGT (pre 9.66±1.11mmol/l, post 8.60±2.00 mmol/l) but not in those with IFG (pre 6.27±1.28mmol/l, post 6.33± 1.55 mmol/l). There were no significant changes in ISI or glucose area under the curve following the RT program.

Conclusions

RT without dietary intervention improves 2-hr oral glucose tolerance in individuals with prediabetes. However, the improvements in glucose homeostasis with RT appear limited to those with IGT or combined IFG and IGT.

Trial Registration

ClinicalTrials.gov: {"type":"clinical-trial","attrs":{"text":"NCT01112709","term_id":"NCT01112709"}}NCT01112709     

Recent advances on the complement system of teleost fish

The complement system plays an essential role in alerting the host of the presence of potential pathogens, as well as in their clearing. In addition, activation of the complement system contributes significantly in the orchestration and development of an acquired immune response. Although the complement system has been studied extensively in mammals, considerably less is known about complement in lower vertebrates, in particular teleost fish. Here we review our current understanding of the role of fish complement in phagocytosis, respiratory burst, chemotaxis and cell lysis. We also thoroughly review the specific complement components characterized thus far in various teleost fish species. In addition, we provide a comprehensive compilation on complement host-pathogen interactions, in which we analyze the role of fish complement in host defense against bacteria, viruses, fungi and parasites. From a more physiological perspective, we evaluate the knowledge accumulated on the influence of stress, nutrition and environmental factors on levels of complement activity and components, and how the use of this knowledge can benefit the aquaculture industry. Finally, we propose future directions that are likely to advance our understanding of the molecular evolution, structure and function of complement proteins in teleosts. Such studies will be pivotal in providing new insights into complement-related mechanisms of recognition and defense that are essential to maintaining fish homeostasis.     

Structural and functional characterization of complement C4 and C1s-like molecules in teleost fish: insights into the evolution of classical and alternative pathways

There is growing evidence that certain components of complement systems in lower vertebrates are promiscuous in their modes of activation through the classical or alternative pathways. To better understand the evolution of the classical pathway, we have evaluated the degree of functional diversification of key components of the classical and alternative pathways in rainbow trout, an evolutionarily relevant teleost species. Trout C4 was purified in two distinct forms (C4-1 and C4-2), both exhibiting the presence of a thioester bond at the cDNA and protein levels. C4-1 and C4-2 bound in a similar manner to trout IgM-sensitized sheep erythrocytes in the presence of Ca(2+)/Mg(2+), and both C4 molecules equally restored the classical pathway-mediated hemolytic activity of serum depleted of C3 and C4. Reconstitution of activity was dependent on the presence of both C3-1 and C4-1/C4-2 and on the presence of IgM bound to the sheep erythrocytes. A C1s-like molecule was shown to cleave specifically purified C4-1 and C4-2 into C4b, while failing to cleave trout C3 molecules. The C1s preparation was unable to cleave trout factor B/C2 when added in the presence of C3b or C4b molecules. Our results show a striking conservation of the mode of activation of the classical pathway. We also show that functional interchange between components of the classical and alternative pathway in teleosts is more restricted than was anticipated. These data suggest that functional diversification between the two pathways must have occurred shortly after the gene duplication that gave rise to the earliest classical pathway molecules.     

Characterization of a C3a receptor in rainbow trout and Xenopus: the first identification of C3a receptors in nonmammalian species

Virtually nothing is known about the structure, function, and evolutionary origins of the C3aR in nonmammalian species. Because C3aR and C5aR are thought to have arisen from the same common ancestor, the recent characterization of a C5aR in teleost fish implied the presence of a C3aR in this animal group. In this study we report the cloning of a trout cDNA encoding a 364-aa molecule (TC3aR) that shows a high degree of sequence homology and a strong phylogenetic relationship with mammalian C3aRs. Northern blotting demonstrated that TC3aR was expressed primarily in blood leukocytes. Flow cytometric analysis and immunofluorescence microscopy showed that Abs raised against TC3aR stained to a high degree all blood B lymphocytes and, to a lesser extent, all granulocytes. More importantly, these Abs inhibited trout C3a-mediated intracellular calcium mobilization in trout leukocytes. A fascinating structural feature of TC3aR is the lack of a significant portion of the second extracellular loop (ECL2). In all C3aR molecules characterized to date, the ECL2 is exceptionally large when compared with the same region of C5aR. However, the exact function of the extra portion of ECL2 is unknown. The lack of this segment in TC3aR suggests that the extra piece of ECL2 was not necessary for the interaction of the ancestral C3aR with its ligand. Our findings represent the first C3aR characterized in nonmammalian species and support the hypothesis that if C3aR and C5aR diverged from a common ancestor, this event occurred before the emergence of teleost fish.     

Peste des Petits Ruminants Virus Tissue Tropism and Pathogenesis in Sheep and Goats following Experimental Infection

Peste des petits ruminants (PPR) is a viral disease which primarily affects small ruminants, causing significant economic losses for the livestock industry in developing countries. It is endemic in Saharan and sub-Saharan Africa, the Middle East and the Indian sub-continent. The primary hosts for peste des petits ruminants virus (PPRV) are goats and sheep; however recent models studying the pathology, disease progression and viremia of PPRV have focused primarily on goat models. This study evaluates the tissue tropism and pathogenesis of PPR following experimental infection of sheep and goats using a quantitative time-course study. Upon infection with a virulent strain of PPRV, both sheep and goats developed clinical signs and lesions typical of PPR, although sheep displayed milder clinical disease compared to goats. Tissue tropism of PPRV was evaluated by real-time RT-PCR and immunohistochemistry. Lymph nodes, lymphoid tissue and digestive tract organs were the predominant sites of virus replication. The results presented in this study provide models for the comparative evaluation of PPRV pathogenesis and tissue tropism in both sheep and goats. These models are suitable for the establishment of experimental parameters necessary for the evaluation of vaccines, as well as further studies into PPRV-host interactions.     

Seroprevalence of Sheep and Goat Pox,Peste Des Petits Ruminants and Rift Valley Fever in Saudi Arabia

Sheep and goat pox, peste des petits ruminants and Rift Valley fever are important diseases of small ruminant livestock. Sheep and goat pox, along with peste des petits ruminants, are endemic throughout most of Africa, Asia and the Middle East. Whereas Rift Valley fever is endemic in Africa, outbreaks in the Middle East have been reported over the past decade, including the Arabian Peninsula. Saudi Arabia is a major importer of livestock, and understanding the prevalence of these viral infections would be useful for disease control. In this study, sera from sheep and goats were collected from 3 regions in Saudi Arabia. They were evaluated for antibodies specific to sheep and goat pox, peste des petits ruminants and Rift Valley fever by virus neutralization assays. To the best of our knowledge, this is the first study to evaluate the seroprevalence of these viruses in sheep and goats.