The mechanical behavior of activated skeletal muscle during stretch: effects of muscle unloading and MyHC isoform shifts

2007 ◽  
Vol 103 (4) ◽  
pp. 1150-1160 ◽  
Author(s):  
Vincent J. Caiozzo ◽  
Heather Richmond ◽  
Serge Kaska ◽  
Dahlia Valeroso
Keyword(s):  
Skeletal Muscle ◽  
Initial Phase ◽  
Muscle Length ◽  
Hindlimb Suspension ◽  
Control Group ◽  
Joint Stability ◽  
Sprague Dawley ◽  
Group 4 ◽  
Sprague Dawley Rats ◽  
Group 2

The response of activated skeletal muscle to a ramp stretch is complex. Force rises rapidly above the isometric plateau during the initial phase of stretch. However, after a strain of ∼1–2%, force yields and continues to rise but with a slower slope. The resistance to stretch during the initial phase can be characterized by the stiffness of the muscle and/or the preyield modulus ( Epre). Similarly, a measure of modulus also can be used to characterize the postyield modulus response ( Epost). This study examined the effects of muscle atrophy and altered myosin heavy chain (MyHC) isoform composition on both Epre and Epost. Female Sprague-Dawley rats were assigned to 1) control group, 2) a hypothyroid group, 3) a hyperthyroid group, 4) a hindlimb suspension group, and 5) a hindlimb suspension + hyperthyroid group. These interventions were used either to alter the MyHC isoform composition of the muscle or to induce atrophy. Soleus muscles were stretched at strain rates that ranged from ∼0.15 to 1.25 muscle length/s. The findings of this study demonstrate that 4 wk of hindlimb suspension can produce a large (i.e., 40–60%) reduction in Epre. Hindlimb suspension did not produce a proportional change in Epost. Analyses of the Epre-strain rate relationship demonstrated that there was little dependence on MyHC isoform composition. In summary, the disproportionate decrease in Epre of atrophied muscle has important implications with respect to issues related to joint stability, especially under dynamic conditions and conditions where the static joint stabilizers (i.e., ligaments) have been compromised by injury.

Effects of xylene and formaldehyde inhalations on renal oxidative stress and some serum biochemical parameters in rats

2007 ◽  
Vol 23 (2) ◽  
pp. 115-120 ◽  
Author(s):  
Cavit Kum ◽  
Selim Sekkin ◽  
Funda Kiral ◽  
Ferda Akar
Keyword(s):  
Oxidative Stress ◽  
Total Protein ◽  
Biochemical Parameters ◽  
Control Group ◽  
Serum Biochemical Parameters ◽  
Sprague Dawley ◽  
Group 4 ◽  
Sprague Dawley Rats ◽  
Serum Biochemical ◽  
Group 2

In this study, it was aimed to demonstrate the possible renal oxidative stress and some serum biochemical parameters and their alterations caused by the exposure to xylene and formaldehyde (HCHO) in rats. Weighing 150—200 g, 12-week-old, 24 female Sprague-Dawley rats were used. The rats were randomly divided into four groups: Group 1 (control), Group 2 (300-ppm technical xylene), Group 3 (6-ppm HCHO) and Group 4 (150-ppm technical xylene + 3-ppm HCHO). The animals were exposed to gases eight hours per day for six weeks. Superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) activities, glutathione (GSH) and malondialdehyde (MDA) levels were measured. In addition, serum total protein, albumin, urea and creatinine levels were evaluated. Compared with the control animals, urea levels increased significantly in all groups ( P < 0.001). GSH activities and MDA levels increased in xylene and xylene + HCHO groups ( P < 0.05). No statistically considerable differences were found in SOD, CAT and GSH-Px activities, total protein, albumin and creatinine levels among all groups ( P > 0.05). The present study indicates but not statistically confirms the renal toxicity of the exposures to xylene, HCHO and a mixture of them.

scholarly journals Effects of Tocotrienol and Lovastatin Combination on Osteoblast and Osteoclast Activity in Estrogen-Deficient Osteoporosis

2012 ◽  
Vol 2012 ◽  
pp. 1-9 ◽  
Author(s):  
Saif Abdul-Majeed ◽  
Norazlina Mohamed ◽  
Ima-Nirwana Soelaiman
Keyword(s):  
Bone Formation ◽  
Combined Treatment ◽  
Female Rats ◽  
Control Group ◽  
Sprague Dawley ◽  
Hmgcoa Reductase ◽  
Reductase Inhibitors ◽  
Group 4 ◽  
Group 3 ◽  
Group 2

Statins are HMGCoA reductase inhibitors and had been demonstrated to stimulate bone formation in rodents after high oral doses. Observational studies on patients treated with oral statins were varied. Delta-tocotrienol had been found to stimulate the cleavage of HMGCoA reductase and inhibit its activity. Tocotrienols were found to have both catabolic and anabolic effects on bone in different animal models of osteoporosis. The current study aimed to ascertain the effects of delta–tocotrienol and lovastatin combination on biochemical and static bone histomorphometric parameters in a postmenopausal rat model at clinically tolerable doses. 48 Sprague Dawley female rats were randomly divided into 6 groups: (1) baseline control group; (2) sham-operated control group; (3) ovariectomised control group; (4) ovariectomised and 11 mg/kg lovastatin; (5) ovariectomised and 60 mg/kg delta-tocotrienol; (6) ovariectomised and 60 mg/kg delta-tocotrienol + 11 mg/kg lovastatin. These treatments were given daily via oral gavage for 8 weeks. Delta-tocotrienol plus lovastatin treatment significantly increased bone formation and reduced bone resorption compared to the other groups. Therefore, the combined treatment may have synergistic or additive effects and have the potential to be used as an antiosteoporotic agent in patients who are at risk of both osteoporosis and hypercholesterolemia, especially in postmenopausal women.

scholarly journals Assessment of Nanosilver Hemocompatibility in Prehypertensive Salt-Induced Animal Model

2021 ◽  
Vol 2 (7) ◽  
pp. 567-573
Author(s):  
Ogechukwu K Uche ◽  
Esiri F Ohiambe ◽  
Fabian C Amechina
Keyword(s):  
Tap Water ◽  
Osmotic Fragility ◽  
Sprague Dawley ◽  
Group 4 ◽  
Sprague Dawley Rats ◽  
Normal Rat ◽  
Group 3 ◽  
Group 2 ◽  
The Impact ◽  
Group 1

Aim: There are Conflicting reports on safety profile of nanoparticles on biological cells. This study evaluated the impact of nanosilver on hemocompatibility on salt-loaded rats. Materials and Methods: Sprague-Dawley rats [(inbred) (120-140 g)] randomly divided into of 4 groups, (n = 6) were studied. Group 1(control) received normal rat chow and tap water, Group 2 received rat chow containing 8% NaCl [(salt-loaded rats (SLRs)]. Group 3 received rat chow + Nanosilver Solution (NS) 0.18 mL 10 ppm/kg/day. Group 4 comprised SLRs + NS. After 6 weeks oral gavage treatments, measurements of Blood pressure (Bp) and Heart Rate (HR) were by pressure transducer via cannulation of left common carotid artery following anaesthesia with urethane. HR was computed by the number of arterial pulse per 60 seconds. 5 ml of blood for WBC, PLATELETS, RBC, PCV, HB, MCH, MCHC and MCV analyses using automated haematology analyser and Osmotic fragility reactivity with standard spectrophotometer at 540 nm wavelength. Results: Exposure of nanosilver to normotensive rats resulted in significantly lower RBC level compared with control, whereas RBC level in Salt-Loaded Co-Treated Nanosilver (SCNS) was comparable with the SLRs. The tenet was the same for HB, PCV, MCH and MCHC. Nanosilver induced leukopenia in normotensive compared with control and prevented WBC elevation in SCNS. Platelets significantly increased in Nanosilver-Treated Normotensive Rats (NTNRs) compared with control and decreased in SCNS. Osmotic burst resistance increased in NTNRs and decreased in cells from treated groups. Conclusion: Chronic exposure of nanosilver to salt loaded rats alters haematological parameters which may worsen circulatory function and activate risk factors of cardiovascular disorders.

scholarly journals Comparison of the effects of adenosine, isoproterenol and their combinations on pulmonary transit time in rats using contrast echocardiography

2021 ◽  
Author(s):  
Feng Su ◽  
Yun-Yan Shi ◽  
Bo Wang ◽  
Xiao-Zhi Zheng
Keyword(s):  
Transit Time ◽  
Characteristic Curve ◽  
Contrast Echocardiography ◽  
Control Group ◽  
Sprague Dawley ◽  
Group 4 ◽  
Group 2 ◽  
Clinical Transformation ◽  
Pulmonary Transit Time ◽  
Youden’S Index

Aims: To compare the effects of adenosine (Ade), isoproterenol (Iso) and their combinations on pulmonary transit time (PTT) in rats using contrast echocardiography.Material and methods: Thirty-two adult Sprague Dawley (SD) rats were divided into four groups (n=8) according the medicines of tail-intravenous injection: Group 1, control; Group 2, Ade; Group 3, Iso; Group 4, Ade+Iso. They all underwent conventional echocardiography and contrast echocardiography with measurements of PTT.Results: With Ade injection, OnsetRV-OnsetLV PTT (PTT1), PeakRV-PeakLV PTT (PTT2) and OnsetRV-PeakLV PPT (PTT3) decreased and PTT3 had the largest decreased percentage, with the highest performance in differentiating the Ade group from the control group [the area under receiver operating characteristic curve (AUC), sensitivity and Youden’s index was maximal]. With Iso injection, PTT1, PTT2 and PTT1 all increased and PTT1 had the largest increased percentage, with the highest performance in differentiating the Iso group from the control group (AUC, sensitivity and Youden’s index was maximal). With a combination injection of Ade and Iso, the PTT values were similar to the control group and no PTT coulddifferentiate the Ade+Iso group from the control group.Conclusions: Ade or/and Iso exerted distinct effects on PTT. These findings remind us that it is a necessary to consider the effects of medicine (especially cardiopulmonary vasoactive drugs) on the PTT values. At the same time, it provides the basis for the clinical transformation of consecutive Iso/Ade treatment from the perspective of pulmonary circulation.

scholarly journals Effect of the Lipoxygenase Inhibitor Baicalein on Muscles in Ovariectomized Rats

2016 ◽  
Vol 2016 ◽  
pp. 1-14 ◽  
Author(s):  
D. Saul ◽  
J. H. Kling ◽  
R. L. Kosinsky ◽  
D. B. Hoffmann ◽  
M. Komrakova ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Creatine Kinase ◽  
Fibre Diameter ◽  
Serum Creatine Kinase ◽  
Ovariectomized Rats ◽  
Control Group ◽  
Sprague Dawley ◽  
Lipoxygenase Inhibitor ◽  
Sprague Dawley Rats ◽  
Inflammatory Effect

Sarcopenia, a loss of muscle mass accompanying osteoporosis, leads to falls and fall-related injuries. Baicalein, as a phytochemical agent, has an antioxidative and anti-inflammatory effect in muscle. In this study, sixty-one female Sprague Dawley rats were divided into five groups: four groups were ovariectomized (OVX) and one control group was nonovariectomized (NON-OVX). Eight weeks after ovariectomy, three disparate concentrations (1 mg/kg body weight (BW), 10 mg/kg BW, and 100 mg/kg BW) of baicalein were applied subcutaneously daily in three OVX groups. Mm. soleus, gastrocnemius, and longissimus were extracted; their diameter, area, relation to body, and muscle weights as well as number of capillaries per fibre were recorded. In Mm. soleus and gastrocnemius, the baicalein effect (increasing number of capillaries per fibre) was proportional to the dose applied. The fibre diameters and area under baicalein treatment were significantly greater compared to OVX and NON-OVX groups. In M. longissimus, we observed a shift to type IIa fibres. Serum creatine kinase levels were significantly lower in highest baicalein concentration group. We conclude that baicalein can stimulate angiogenesis, though not fibre type-specific, in skeletal muscle and reduce the estrogen-related loss of fibre diameter and area in the skeletal muscle in rats. Therefore, a protective effect of baicalein on muscle cells can be assumed.

Doxorubicin-Induced Cardiac Abnormalities in Rats: Attenuation via Sandalwood Oil

Pharmacology ◽  
2019 ◽  
Vol 105 (9-10) ◽  
pp. 522-530 ◽  
Author(s):  
Nancy S. Younis
Keyword(s):  
Inflammatory Response ◽  
Troponin T ◽  
Cardiac Injury ◽  
Cardiac Biomarkers ◽  
Sprague Dawley ◽  
Necrosis Factor Alpha ◽  
Group 4 ◽  
Sprague Dawley Rats ◽  
Sandalwood Oil ◽  
Group 2

<b><i>Introduction:</i></b> The clinical use of doxorubicin (DOX) is challenged by its incremental dose-related cardiotoxicity. <b><i>Objective:</i></b> The aim of the hereby study was to investigate sandalwood essential oil (SEO) against DOX-induced cardiac toxicity. <b><i>Methods:</i></b> Male Sprague-Dawley rats were allocated into 4 groups. Groups 1 signified the control, whereas group 2 administered 100 mg/kg/day SEO, both act as control. In group 3, DOX was given intraperitoneal in a dose of 3 mg/kg/ every other day for 2 weeks to induced cardiotoxicity. While group 4 received a combination of SEO and DOX for 2 weeks. DOX prompted variations were assessed by measuring cardiac injury biomarkers, including creatine phosphokinase, cardiac troponin T, and lactate dehydrogenase (LDH), electrocardiogram (ECG) fluctuations, heart rate (HR), and blood pressure (BP) indices. The effect of both DOX and SEO on various antioxidants such as glutathione, superoxide dismutase, and catalase and inflammatory mediators including interleukin-1β, tumor necrosis factor-alpha, and NF-κB was quantified. <b><i>Results:</i></b> DOX augmented cardiac injury biomarkers, altered ECG, deceased HR and antioxidants, and finally increased BP indices. Treatment with SEO significantly (<i>p</i> &#x3c; 0.05) decreased cardiac biomarkers and reversing ECG changes and BP. Moreover, treatment with SEO enhanced HR anomalies and antioxidant activity reduction and precluded the intensive inflammatory response induced by DOX. <b><i>Conclusion:</i></b> SEO may have the potential of mitigating cardiac rhythm and BP indices changes induced with DOX. SEO modifications may be due to antioxidant capacity improvement and inflammatory response prohibition of the heart muscle.

scholarly journals Resveratrol chemoprotective effect and COX 2 down regulation in tumor suppression in DMBA induced breast cancer in female Sprague Dawley rats

2017 ◽  
Vol 6 (6) ◽  
pp. 1517
Author(s):  
Aneena Suresh ◽  
Rajat Rana ◽  
Keerthana C.
Keyword(s):  
Breast Cancer ◽  
Diet Group ◽  
Sprague Dawley ◽  
Down Regulation ◽  
Tumor Multiplicity ◽  
Group 4 ◽  
Sprague Dawley Rats ◽  
Group 3 ◽  
Cox 2 ◽  
Group 2

Background: Aim of the study was to assess the Chemo protective role of Resveratrol in 7,12‑Dimethylbenzanthracene (DMBA) induced breast cancer in Female Sprague Dawley rats and its possible role in down regulation of COX 2, an enzyme known to be expressed in breast cancer tissues.Methods: A total of 40 female Sprague dawley rats (total 4 groups, n = 10 per group) 6 weeks old, group 1 on pulverized rodent diet, group 2 DMBA with diet, group 3 DMBA and diet with Resveratrol 100mcg, group 4 DMBA and diet with Resveratrol 200mcg. After 120 days experiment was terminated and tumors were analyzed for multiplicity, incidence and histology. Cox 2 expression was analyzed by Western blot analysis. Values were statistically tested using one way variance and Tukey’s comparison test.Results: Body weight and tumor volume was similar, there was remarkable high latency period for tumor onset and reduction in tumor multiplicity andincidence in resveratrol treated groups. Tumor incidence was 42.27±10.17 for Group 2, 21.91±5.87 for Group 3, 13.73±3.98 for group 4. Tumor multiplicity was reported as 0.8909±0.30 for group 2, 0.1036±0.04 for group 3, 0.04545±0.02 for group 4. Histopathological analysis revealed ductal carcinoma in group 2, minor tissue necrosis in group 3 and fibroadenoma in group 4.Conclusions: Resveratrol has chemoprevention action against DMBA induced breast cancer and suppresses COX 2 expression in breast carcinoma.

scholarly journals Preventive and therapeutic effects of relaxin on bisphosphonaterelated osteonecrosis of the jaw: an experimental study in rats

2020 ◽  
Vol 23 (1) ◽  
Author(s):  
Tuba Develi ◽  
Sina Uckan ◽  
Burak Bayram ◽  
Kagan Deniz ◽  
Remzi Saban Erdem ◽  
...  
Keyword(s):  
Osteonecrosis Of The Jaw ◽  
Incidence Rates ◽  
Therapeutic Effects ◽  
Differentiation Process ◽  
Sprague Dawley ◽  
Group 4 ◽  
Sprague Dawley Rats ◽  
Group 3 ◽  
Group 2 ◽  
Group 1

Objective: Bisphosphonate-related osteonecrosis of the jaw (BRONJ) is a challenging complication of chronic bisphosphonate (BP) use. The hormone relaxin is able to induce the multistep differentiation process of human osteoclastogenesis, exhibits anti-fibrotic and anti-inflammatory actions, and promotes vasodilatation, wound healing, and angiogenesis. The present study aimed to evaluate the effects of relaxin in the prevention and management of BRONJ. Material and Methods: Thirty-six male Sprague Dawley rats were randomly divided into four groups. Rats in group 1 (n = 10) received relaxin and BP simultaneously for 12 weeks. Rats in group 2 (n = 10) received injections of BP for 12 weeks, followed by relaxin for another 12 weeks. Rats in group 3 (n = 10) received only BP injections, and those in group 4 (control, n = 6) received only saline. Necrosis and inflammation in the rats’ mandibles were evaluated as indicators of BRONJ. Results: Necrosis and inflammation were not detected in group 1 (BP + relaxin). In group 3 (BP only), incidence rates of necrosis and inflammation were 90% and 60%, respectively. Conclusions: Our findings suggest that relaxin may be potently effective in preventing BRONJ and have some benefit in the treatment of existing BRONJ.KEYWORDSAnimal model; BRONJ; Relaxin.

scholarly journals The Effects of Curcumin on Wound Healing in a Rat Model of Nasal Mucosal Trauma

2017 ◽  
Vol 2017 ◽  
pp. 1-6 ◽  
Author(s):  
Gokhan Emiroglu ◽  
Zerrin Ozergin Coskun ◽  
Yildiray Kalkan ◽  
Ozlem Celebi Erdivanli ◽  
Levent Tumkaya ◽  
...  
Keyword(s):  
Wound Healing ◽  
Dimethyl Sulfoxide ◽  
Control Group ◽  
Albino Rats ◽  
Sprague Dawley ◽  
Group 4 ◽  
Leukocytic Infiltration ◽  
Sham Control Group ◽  
Group 2 ◽  
Group 1

We explored the effects of topical curcumin on the healing of nasal mucosal wounds. A total of 32 Sprague-Dawley Albino rats were randomized in equal numbers into four groups, and unilateral nasal wounds were created using an interdental brush. Group 1 (the sham-control group) contained untreated rats with traumatized right-side nasal cavities; Group 2 and 3 rats were similarly traumatized and treated with topical curcumin (5 and 10 mg/mL) dissolved in dimethyl sulfoxide daily for 7 days after trauma; Group 4 rats were treated with topical dimethyl sulfoxide only. All rats were decapitated on day 15 and the healing sites evaluated by blinded observers in terms of the presence of cellular hyperplasia, goblet cell hypertrophy and degeneration, leucocytic infiltration, ciliary loss and degeneration, edema, and vascular dilation. On histopathological evaluation, all of cellular hyperplasia, leukocytic infiltration, and edema were significantly reduced in Group 3 compared with Group 1 (p=0.001, p=0.004, and p=0.008, resp.). Thus, curcumin reduced the inflammatory response and significantly accelerated wound healing.

scholarly journals EFFECT OF VITAMIN E (α TOCOPHEROL) ADMINISTRATION ON APOPTOSIS OF GERMINAL CELLS EPITHELIUM TESTIS IN SPRAGUE DAWLEY WHITE STRAIN RATS AFTER EXPOSED BY CISPLATIN

2019 ◽  
Vol 26 (1) ◽  
Author(s):  
Achmad Nugroho ◽  
Wahjoe Djatisoesanto ◽  
Doddy M Soebadi
Keyword(s):  
Vitamin E ◽  
Epithelial Cells ◽  
Protective Effect ◽  
Positive Control ◽  
Negative Control ◽  
Sprague Dawley ◽  
Group 4 ◽  
Sprague Dawley Rats ◽  
Significant Difference ◽  
Group 2

Objective: To determine the differences of germinal epithelial testicular cell apoptosis in white Sprague Dawley strain rat that received combination of cisplatin and vitamin E compared to Sprague Dawley strain rat that received cisplatin only. Material & Methods:  Twenty four Sprague Dawley rats were divided into 4 groups randomly. Group 1 Negative Control (NC) was given an injection of 1 cc 0.9% normal saline intraperitoneally as a placebo, group 2 Positive Control (PC) was given 5 mg/kgBW cisplatin intraperitoneally, group 3 (P1) was given cisplatin injection 5 mg/kgBW intraperitoneally + vitamin E (α tocopherol) 50 mg/kgBW by gavage and group 4 (P2) was given cisplatin injection 5 mg/kgBW intraperitoneally + vitamin E (α tocopherol) 200 mg/kgBW by gavage. Vitamin E (α tocopherol) was given 3 weeks before up to 4 weeks after cisplatin injection. Observation of the germinal epithelial cells apoptosis was carried out by calculating germinal epithelial cells apoptosis in the cross-section preparations of the seminiferous tubule which gave a positive reaction to the apoptag staining, using a 400x magnification light microscope. Results: Apoptosis on positive control (PC) group was different significantly compared to the negative control (NC) group (p<0.05). There was a significant difference in the apoptosis of germinal epithelial testicular cells in the cisplatin + vitamin E 50 mg/kgBW compared to the PC group (p<0.05). The cisplatin + vitamin E 200 mg/kgBW group; had a lower number of apoptosis compared to the cisplatin + vitamin E 50 mg/kgBW (p<0.05). Conclusion: Vitamin E provides a protective effect on decreasing the amount of apoptosis due to cisplatin exposure. The protective effect of vitamin E is dose-dependent.

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