Effects of ovariectomy and resistance training on MMP-2 activity in skeletal muscle

Matrix metallopeptidases (MMPs) are crucial to the maintenance of healthy tissue. The aim of this study was to investigate MMP-2 activity in gastrocnemius, soleus, tibialis anterior (TA), and extensor digitorium longus (EDL) muscle after resistance training in ovariectomized rats. Wistar adult female rats were grouped into 7 groups (n = 10 per group): sedentary (Sed-Intact); ovariectomized sedentary (Sed-Ovx); pseudo-ovariectomized sedentary (Sed-Pseudo); acute exercise (AcuteEx-Intact); ovariectomized acute exercise (AcuteEx-Ovx); strength trained (ChronicEx-Intact); and ovariectomized strength trained (ChronicEx-Ovx). A 12-week resistance training period, during which the animals climbed a 1.1-m vertical ladder with weights secured to their tails, was used. The sessions were performed once every 3 days, with 4–9 climbs and 8–12 dynamic movements per climb. The MMP-2 activity was analyzed by zymography. There was higher MMP-2 activity in soleus muscle in the ChronicEx-Intact and ChronicEx-Ovx groups, and lower MMP-2 activity in the AcuteEx-Ovx group, compared with the Sed-Intact group (p ≤ 0.05). The Sed-Ovx and ChronicEx-Ovx groups presented lower MMP-2 activity than the Sed-Intact group in TA. There was higher MMP-2 activity in AcuteEx-Intact and the AcuteEx-Ovx compared with the Sed-Intact and Sed-Ovx in TA, respectively (p ≤ 0.05). In TA and EDL, training increased MMP-2 activity in the Sed-Intact group. No statistically significant alterations were observed for gastrocnemius muscle. Strength training increases MMP-2 activity in soleus, TA, and EDL muscle, which may be important for muscle remodeling. Ovariectomy downregulates MMP-2 in TA and EDL, which may compromise muscle function.

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Morphological and Biochemical Effects on the Skeletal Muscle of Ovariectomized Old Female Rats Submitted to the Intake of Diets with Vegetable or Animal Protein and Resistance Training

Oxidative Medicine and Cellular Longevity ◽

10.1155/2016/9251064 ◽

2016 ◽

Vol 2016 ◽

pp. 1-10 ◽

Cited By ~ 7

Author(s):

Glaucia Figueiredo Braggion ◽

Elisabete Ornelas ◽

Jurema Carmona Sattin Cury ◽

Natália Edviges Alves Lima ◽

Rita C. Aquino ◽

...

Keyword(s):

Resistance Training ◽

Functional Limitations ◽

The Elderly ◽

Volume Density ◽

Female Rats ◽

Medial Gastrocnemius ◽

Ovariectomized Rats ◽

Type I ◽

Cross Sectional ◽

Protein Mass

Introduction. Sarcopenia is a process characterized by reduction in protein mass and muscle strength with increasing age, especially in the postmenopausal period, resulting in functional limitations and with great impact on the physical autonomy of the elderly.Objective. To evaluate the effects of diets with vegetable proteins (VP) or animal proteins (AP) associated with resistance training (RT) on the structural and biochemical parameters of the medial gastrocnemius muscle in Wistar rats with sarcopenia.Methods. An experimental model with ovariectomized rats was used to induce sarcopenia and resistance training. The histochemical technique was used for the typing of muscle fibers, the cross-sectional area of myocytes, and volume densities of myocytes and interstitium; the technique of Picrosirius stain was used to highlight the collagen fibers.Results. The VP diet was not able to minimize the effects of sarcopenia in the medial gastrocnemius of sedentary animals and when associated with RT, it promoted maintenance of the CSA, attenuating the atrophy of type IIB fibers in the medial gastrocnemius. The AP diet in sedentary animals protected the type I fibers. When combined with RT, the AP promoted muscle remodeling, with reduction in volume density of type I and IIA fibers, and increase of IIB fibers, together with an increase in collagen volume density.Conclusion. The data suggest a tendency to better results of hypertrophy in animal groups that consumed the AP diet, even the sedentary animals, although more evident in those trained.

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Resistance Training Improves Muscle Function and Body Composition in Patients With Hyperthyroidism

Yearbook of Sports Medicine ◽

10.1016/s0162-0908(08)70162-4 ◽

2007 ◽

Vol 2007 ◽

pp. 192-194

Author(s):

R.J. Shephard

Keyword(s):

Body Composition ◽

Resistance Training ◽

Muscle Function

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Changes in the characteristics of pulsatile luteinizing hormone secretion during the oestrous cycle and after ovariectomy and oestrogen treatment in female rats

Journal of Endocrinology ◽

10.1677/joe.0.0940177 ◽

1982 ◽

Vol 94 (2) ◽

pp. 177-182 ◽

Cited By ~ 16

Author(s):

Takashi Higuchi ◽

Masazumi Kawakami

Keyword(s):

Hormone Secretion ◽

Pulse Amplitude ◽

Pulse Frequency ◽

Oestrous Cycle ◽

Female Rats ◽

Ovariectomized Rats ◽

Luteinizing Hormone Secretion ◽

Oestrogen Treatment ◽

Serum Lh ◽

Lh Release

Changes in the characteristics of LH secretory pulses in female rats were determined in different hormonal conditions; during the oestrous cycle and after ovariectomy and oestrogen treatment. The frequency and amplitude of the LH pulses were stable during the oestrous cycle except at oestrus when a pattern could not be discerned because of low LH concentrations. These were significantly lower than those measured during other stages of the cycle. Mean LH concentrations and LH pulse amplitudes increased with time up to 30 days after ovariectomy. The frequency of the LH pulse was unchanged 4 days after ovariectomy when mean LH levels had already increased. The frequency increased 10 days after ovariectomy and then remained stable in spite of a further increase in mean serum LH concentrations. Oestradiol-17β injected into ovariectomized rats caused a decrease in LH pulse amplitude but no change in pulse frequency. One day after treatment with oestradiol benzoate no LH pulse was detectable, probably because the amplitude was too small. A generator of pulsatile LH release is postulated and an oestrogen effect on its function is discussed.

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The Increase in Signaling by Kisspeptin Neurons in the Preoptic Area and Associated Changes in Clock Gene Expression That Trigger the LH Surge in Female Rats Are Dependent on the Facilitatory Action of a Noradrenaline Input

Endocrinology ◽

10.1210/en.2015-1323 ◽

2016 ◽

Vol 157 (1) ◽

pp. 323-335 ◽

Cited By ~ 7

Author(s):

Bruna Kalil ◽

Aline B. Ribeiro ◽

Cristiane M. Leite ◽

Ernane T. Uchôa ◽

Ruither O. Carolino ◽

...

Keyword(s):

Gene Expression ◽

Median Eminence ◽

Preoptic Area ◽

Clock Genes ◽

Third Ventricle ◽

Female Rats ◽

Ovariectomized Rats ◽

Lh Surge ◽

Clock Gene Expression

Abstract In rodents, kisspeptin neurons in the rostral periventricular area of the third ventricle (RP3V) of the preoptic area are considered to provide a major stimulatory input to the GnRH neuronal network that is responsible for triggering the preovulatory LH surge. Noradrenaline (NA) is one of the main modulators of GnRH release, and NA fibers are found in close apposition to kisspeptin neurons in the RP3V. Our objective was to interrogate the role of NA signaling in the kisspeptin control of GnRH secretion during the estradiol induced LH surge in ovariectomized rats, using prazosin, an α1-adrenergic receptor antagonist. In control rats, the estradiol-induced LH surge at 17 hours was associated with a significant increase in GnRH and kisspeptin content in the median eminence with the increase in kisspeptin preceding that of GnRH and LH. Prazosin, administered 5 and 3 hours prior to the predicted time of the LH surge truncated the LH surge and abolished the rise in GnRH and kisspeptin in the median eminence. In the preoptic area, prazosin blocked the increases in Kiss1 gene expression and kisspeptin content in association with a disruption in the expression of the clock genes, Per1 and Bmal1. Together these findings demonstrate for the first time that NA modulates kisspeptin synthesis in the RP3V through the activation of α1-adrenergic receptors prior to the initiation of the LH surge and indicate a potential role of α1-adrenergic signaling in the circadian-controlled pathway timing of the preovulatory LH surge.

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OESTROGEN RESPONSES OF RATS NEONATALLY STERILIZED WITH STEROIDS

Journal of Endocrinology ◽

10.1677/joe.0.0450415 ◽

1969 ◽

Vol 45 (3) ◽

pp. 415-420 ◽

Cited By ~ 21

Author(s):

T. R. WRENN ◽

JOAN R. WOOD ◽

J. BITMAN

Keyword(s):

Testosterone Propionate ◽

Female Rats ◽

Ovariectomized Rats ◽

Uterine Weight ◽

Oestradiol Benzoate

SUMMARY At 75 days of age, female rats neonatally sterilized with oestradiol benzoate or testosterone propionate were compared with normal and ovariectomized rats with regard to their 6-hr. response to 0·2 μg. oestradiol 17β. The greatest increases in uterine weight, glucose and glycogen concentrations and per cent uterine water occurred in the ovariectomized animals. A marked oestrogen response also occurred in the animals neonatally sterilized with oestradiol benzoate. The response of the normal rats was slight, and the testosterone propionate-treated rats were the least affected. Adrenal, pituitary, and ovarian weights were found to be affected by the neonatal hormone treatments. Vaginal patency was completely inhibited in the rats injected with testosterone propionate. It is concluded that rats neonatally sterilized with steroids are much less suitable than ovariectomized animals for oestrogen assays.

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The Effects ofCosmos caudatuson Structural Bone Histomorphometry in Ovariectomized Rats

Evidence-based Complementary and Alternative Medicine ◽

10.1155/2012/817814 ◽

2012 ◽

Vol 2012 ◽

pp. 1-6 ◽

Cited By ~ 5

Author(s):

Norazlina Mohamed ◽

Sharon Gwee Sian Khee ◽

Ahmad Nazrun Shuid ◽

Norliza Muhammad ◽

Farihah Suhaimi ◽

...

Keyword(s):

Bone Histomorphometry ◽

Therapeutic Agent ◽

Female Rats ◽

Ovariectomized Rats ◽

Antioxidant Compounds ◽

Protective Agent ◽

Cosmos Caudatus ◽

Bone Damage ◽

Trabecular Separation ◽

Trabecular Number

Osteoporosis is considered a serious debilitating disease.Cosmos caudatus(ulam raja), a plant containing antioxidant compounds and minerals, may be used to treat and prevent osteoporosis. This study determines the effectiveness ofC. caudatusas bone protective agent in postmenopausal osteoporosis rat model. Thirty-two female rats, aged 3 months old, were divided into 4 groups. Group one was sham operated (sham) while group two was ovariectomized. These two groups were given ionized water by forced feeding. Groups three and four were ovariectomized and given calcium 1% ad libitum and force-fed withC. caudatusat the dose of 500 mg/kg, respectively. Treatments were given six days per week for a period of eight weeks. Body weight was monitored every week and structural bone histomorphometry analyses of the femur bones were performed. Ovariectomy decreased trabecular bone volume (BV/TV), decreased trabecular number (Tb.N), and increased trabecular separation (Tb.Sp). Both calcium 1% and 500 mg/kgC. caudatusreversed the above structural bone histomorphometric parameters to normal level.C. caudatusshows better effect compared to calcium 1% on trabecular number (Tb.N) and trabecular separation (Tb.Sp). Therefore,Cosmos caudatus500 mg/kg has the potential to act as the therapeutic agent to restore bone damage in postmenopausal women.

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Resistance training attenuates fat mass regain after weight loss in ovariectomized rats

Maturitas ◽

10.1016/j.maturitas.2009.07.005 ◽

2009 ◽

Vol 64 (1) ◽

pp. 52-57 ◽

Cited By ~ 11

Author(s):

Abdolnaser Pighon ◽

Amélie Paquette ◽

Razieh Barsalani ◽

Natalie Ann Chapados ◽

Rémi Rabasa-Lhoret ◽

...

Keyword(s):

Weight Loss ◽

Resistance Training ◽

Fat Mass ◽

Ovariectomized Rats

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Resistance but not endurance exercise training induces changes in cerebrovascular function in healthy young subjects

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00230.2021 ◽

2021 ◽

Author(s):

Hannah J. Thomas ◽

Channa E. Marsh ◽

Louise H. Naylor ◽

Philip N. Ainslie ◽

Kurt J. Smith ◽

...

Keyword(s):

Resistance Training ◽

Arterial Pressure ◽

Endurance Training ◽

Acute Exercise ◽

Internal Carotid ◽

Cerebrovascular Reactivity ◽

Cerebral Hypoperfusion ◽

Brain Health ◽

Cerebrovascular Resistance ◽

Cerebrovascular Function

Aim: It is generally considered that regular exercise maintains brain health and reduces the risk of cerebrovascular diseases such as stroke and dementia. Since the benefits of different 'types' of exercise are unclear, we sought to compare the impacts of endurance and resistance training on cerebrovascular function. Methods: In a randomized and cross-over design, 68 young healthy adults were recruited to participate in 3-months of resistance and endurance training. Cerebral hemodynamics through the internal carotid, vertebral, middle and posterior cerebral arteries were measured using Duplex ultrasound and transcranial Doppler at rest and during acute exercise, dynamic autoregulation and cerebrovascular reactivity (to hypercapnia). Results: Following resistance, but not endurance training, middle cerebral artery velocity and pulsatility index significantly decreased (P<0.01 and P=0.02, respectively), while mean arterial pressure and cerebrovascular resistance in the middle, posterior and internal carotid arteries all increased (P<0.05). Cerebrovascular resistance in response to acute exercise and hypercapnia also significantly increased following resistance (P=0.02), but not endurance training. Conclusions: Our findings, which were consistent across multiple domains of cerebrovascular function, suggest that episodic increases in arterial pressure associated with resistance training may increase cerebrovascular resistance. The implications of long-term resistance training on brain health require future study, especially in populations with pre-existing cerebral hypoperfusion and/or hypotension.

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Resistance training reduces the acute exercise-induced increase in muscle protein turnover

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.1999.276.1.e118 ◽

1999 ◽

Vol 276 (1) ◽

pp. E118-E124 ◽

Cited By ~ 67

Author(s):

S. M. Phillips ◽

K. D. Tipton ◽

A. A. Ferrando ◽

R. R. Wolfe

Keyword(s):

Resistance Training ◽

Resistance Exercise ◽

Acute Exercise ◽

Muscle Protein ◽

Exercise Bout ◽

Muscle Contractions ◽

Breakdown Rates ◽

Single Bout ◽

Fractional Synthesis ◽

Exercise Induced

We examined the effect of resistance training on the response of mixed muscle protein fractional synthesis (FSR) and breakdown rates (FBR) by use of primed constant infusions of [2H5]phenylalanine and [15N]phenylalanine, respectively, to an isolated bout of pleiometric resistance exercise. Trained subjects, who were performing regular resistance exercise (trained, T; n = 6), were compared with sedentary, untrained controls (untrained, UT; n = 6). The exercise test consisted of 10 sets (8 repetitions per set) of single-leg knee flexion (i.e., pleiometric muscle contraction during lowering) at 120% of the subjects’ predetermined single-leg 1 repetition maximum. Subjects exercised one leg while their contralateral leg acted as a nonexercised (resting) control. Exercise resulted in an increase, above resting, in mixed muscle FSR in both groups (UT: rest, 0.036 ± 0.002; exercise, 0.0802 ± 0.01; T: rest, 0.045 ± 0.004; exercise, 0.067 ± 0.01; all values in %/h; P< 0.01). In addition, exercise resulted in an increase in mixed muscle FBR of 37 ± 5% (rest, 0.076 ± 0.005; exercise, 0.105 ± 0.01; all values in %/h; P < 0.01) in the UT group but did not significantly affect FBR in the T group. The resulting muscle net balance (FSR − FBR) was negative throughout the protocol ( P < 0.05) but was increased in the exercised leg in both groups ( P < 0.05). We conclude that pleiometric muscle contractions induce an increase in mixed muscle protein synthetic rate within 4 h of completion of an exercise bout but that resistance training attenuates this increase. A single bout of pleiometric muscle contractions also increased the FBR of mixed muscle protein in UT but not in T subjects.

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