Isolated Soy Protein Supplementation and Exercise Improve Fatigue-Related Biomarker Levels and Bone Strength in Ovariectomized Mice

Abstract

Isolated soy protein (ISP) is a well-known supplement and has been reported to improve health, exercise performance, body composition, and energy utilization. ISP exhibits multifunctional bioactivities and also contains branched-chain amino acids (BCAAs), which have been confirmed to positively affect body weight (BW) regulation and muscle protein synthesis. The combined effects of BCAA supplements and exercise in older postmenopausal women with osteoporosis, sarcopenia, and obesity have been inadequately investigated. Therefore, in this study, we evaluated the potential beneficial effects of soy protein supplementation and exercise training on postmenopausal mice. Forty mice (14 weeks old) with ovariectomy-induced osteosarcopenic obesity were divided into five groups (n = 8), namely sham ovariectomy (OVX, control), OVX, OVX with ISP supplementation (OVX+ISP), OVX with exercise training (ET, OVX+ET), and OVX with ISP and ET (OVX+ISP+ET). The mice received a vehicle or soy protein (3.8 g/kg BW) by oral gavage for four weeks, and the exercise performance (forelimb grip strength and exhaustive swimming time) was evaluated. In the biochemical profiles, we evaluated the serum glucose level and tissue damage markers, such as lactate, ammonia, glucose, blood urine nitrogen (BUN), and creatinine phosphate kinase (CPK). The body composition was determined by evaluating bone stiffness and muscle mass. All data were analyzed using one-way repeated measures analysis of variance. The physical performance of the OVX+ISP+ET group did not differ from that of the other groups. The OVX+ISP+ET group exhibited lower levels of serum lactate, ammonia, CPK, and BUN as well as economized glucose metabolism after an acute exercise challenge. The OVX+ISP+ET group also exhibited higher muscle mass and bone strength than the OVX group. Our study demonstrated that a combination of ISP supplementation and exercise reduced fatigue and improved bone function in OVX mice.

Effects of Soy Foods in Postmenopausal Women: A Focus on Osteosarcopenia and Obesity

“… 43 BCAAs have been shown to be the main carrier of amino nitrogen between visceral and peripheral tissues (including skeletal muscle), but more importantly they appear to be the most direct cause of muscle protein stimulation. 44 Therefore, consuming BCAAs as a nutritional supplement can improve athletic performance and prevent muscle mass loss due to aging and disease. 45 …”

Amino Acid Nutrition and Metabolism in Health and Disease

“…In addition to the paper by Ribeiro et al [22], other contributions also examined the role of dietary protein/amino acid supply in age-related disease. As menopause is associated with a spike in age-related disease incidence in women [35], Lin et al [36] examined the potential beneficial effects of soy protein supplementation and exercise training on ‘postmenopausal’ mice. They found that a combination of soy protein supplementation and exercise reduced fatigue and improved bone function in ovariectomized mice.…”

Low‐Intensity Exercise Routine for a Long Period of Time Prevents Osteosarcopenic Obesity in Sedentary Old Female Rats, by Decreasing Inflammation and Oxidative Stress and Increasing GDF‐11

“…OSO is associated with a low physical performance, frailty, immobility, falls, fractures, and disability [33,34,45]. There are few rodent models to study OSO, and most of them induce obesity in adult female organisms by performing an ovariectomy to observe the effects on muscle and bone during aging [35,46]. It has been reported that when rats and mice are raised under standard laboratory conditions, with ad libitum access to food and little stimulatory environment for movement, they tend to develop obesity, hypertension, and insulin resistance [28,29].…”

“…The cut-off point to determine that obesity has been established in our OSO model was set when the percentage of body fat is greater than 30%. The cut-off point for osteoporosis was established when the BMD values were less than 2.5 times the SD with respect to the mean value of young adult rats (8 months) [31][32][33][34][35]. Sarcopenia and dinapenia were established when the percentage of LMWB and strength decreased below 2 times the SD with respect to the mean value of young adult rats.…”