Swim therapy-induced tissue specific metabolic responses in male rats

Adipose thermogenic mechanisms by cold, exercise and intermittent fasting: Similarities, disparities and the application in treatment

Given its nonnegligible role in metabolic homeostasis, adipose tissue has been the target for treating metabolic disorders such as obesity, diabetes and cardiovascular diseases. Besides its lipolytic function, adipose thermogenesis has gained increased interest due to the irreplaceable contribution to dissipating energy to restore equilibrium, and its therapeutic effects have been testified in various animal models. In this review, we will brief about the canonical cold-stimulated adipose thermogenic mechanisms, elucidate on the exercise- and intermittent fasting-induced adipose thermogenic mechanisms, with a focus on the similarities and disparities among these signaling pathways, in an effort to uncover the overlapped and specific targets that may yield potent therapeutic efficacy synergistically in improving metabolic health.

Effect of Boric Acid on Metabolic Peptides and Some Biochemical Parameters in Experimental Diabetic Rats

Boron (B) is an element that has recently been wondered and researched in many fields, especially due to its effects on energy metabolism. The aim of this study is to evaluate the effect of boric acid (BA) on newly discovered energy metabolism peptides that have not been studied before. In this study, the effects of 15 mg/kg of BA were evaluated in 24 Wistar rats. Groups were named as control group, 15 mg/kg BA group, streptozotocin (STZ)-induced experimental diabetic group, and STZ-induced experimental diabetic + 15 mg/kg BA administered group (STZ+15 mg/kg BA). Serum asprosin, nesfatin-1, preptin, insulin, total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), aspartate transaminase (AST), alanine transaminase (ALT), and glucose analyses were performed. In this study, the increase in glucose, TG, TC, LDL-C levels, and AST, ALT activities in STZ-induced groups were reduced with BA administration. While HDL-C level significantly decreased in the STZ group, the level approached the control group values after BA administration (p<0.001). As for peptides, although there was a statistically significant increase after 15 mg/kg BA administration, these levels did not approach the control group values (p<0.001). According to the findings, STZ-induced diabetes mellitus and the biochemical processes that develop accordingly change correlatively. This study showed that BA is effective in energy metabolism.

Preptin: A New Bone Metabolic Parameter?

Preptin is a 34-aminoacid peptide derived from the E-peptide of pro-insulin-like growth factor 2 (pro-IGF2) that is co-secreted with insulin and upregulates glucose-mediated insulin secretion. High serum preptin levels were described in conditions associated with insulin resistance, such as polycystic ovary syndrome and type 2 diabetes mellitus (T2M). Insulin and also IGF2 are known to be anabolic bone hormones. The "sweet bone" in T2M usually associates increased density, but altered microarchitecture. Therefore, preptin was proposed to be one of the energy regulatory hormones that positively impacts bone health. Experimental data demonstrate a beneficial impact of preptin upon the osteoblasts. Preptin also appears to regulate osteocalcin secretion, which in turn regulates insulin sensitivity. Preptin is greatly influenced by the glucose tolerance status and the level of physical exercise, both influencing the bone mass. Clinical studies describe low serum preptin concentrations in osteoporosis in both men and women, therefore opening the way towards considering preptin a potential bone anabolic therapy. The current review addresses the relationship between preptin and bone mass and metabolism in the experimental and clinical setting, also considering the effects of preptin on carbohydrate metabolism and the pancreatic-bone loop.

Exercise increases MEF2A abundance in rat cardiac muscle by downregulating microRNA-223-5p

Exercise plays an important role in cardiac health and enhances the transport of glucose in cardiac muscle by increasing the glucose transporter-4 (GLUT4) content at the cell membrane. The GLUT4 gene is a target of myocyte enhancer transcription factor 2A (MEF2A). Several transcription factors are regulated by microRNAs (miRs), small non-coding RNAs that control gene expression at the posttranscriptional level. In this study we tested the hypothesis that exercise regulates the expression of miR-223 and that MEF2A is a direct target of miR-223. Quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) and western blot experiments showed that GLUT4 gene expression and protein abundance increased by 30 and 23%, respectively, in the microsomal fraction immediately after exercise, and had returned to control levels after 18 h. In contrast, the increase in GLUT4 in the membrane fraction was delayed. Exercise also increased the protein abundance of transcription factors involved in GLUT4 expression. Immediately after exercise, the protein abundance of MEF2A, nuclear respiratory factor 1 (NRF1), and forkhead box O1 (FOXO1) increased by 18, 30, and 40%, respectively. qRT-PCR experiments showed that miR-223-3p and miR-223-5p expression decreased immediately after exercise by 60 and 30%, respectively, and luciferase assays indicated that MEF2A is a target of the 5p strand of miR-223. Overexpression of miR-223-5p in H9c2 cells decreased the protein abundance of MEF2A. Our results suggest that the exercise-induced increase in GLUT4 content in cardiac muscle is partly due to the posttranscriptional increase in MEF2A protein abundance caused by the decrease in miR-223-5p expression. The exercise-induced decrease in miR-223-3p expression likely contributes to the increases in NRF1 and FOXO1 abundance and GLUT4 content.

Exercise training maintains cardiovascular health: signaling pathways involved and potential therapeutics

Exercise training has been widely recognized as a healthy lifestyle as well as an effective non-drug therapeutic strategy for cardiovascular diseases (CVD). Functional and mechanistic studies that employ animal exercise models as well as observational and interventional cohort studies with human participants, have contributed considerably in delineating the essential signaling pathways by which exercise promotes cardiovascular fitness and health. First, this review summarizes the beneficial impact of exercise on multiple aspects of cardiovascular health. We then discuss in detail the signaling pathways mediating exercise's benefits for cardiovascular health. The exercise-regulated signaling cascades have been shown to confer myocardial protection and drive systemic adaptations. The signaling molecules that are necessary for exercise-induced physiological cardiac hypertrophy have the potential to attenuate myocardial injury and reverse cardiac remodeling. Exercise-regulated noncoding RNAs and their associated signaling pathways are also discussed in detail for their roles and mechanisms in exercise-induced cardioprotective effects. Moreover, we address the exercise-mediated signaling pathways and molecules that can serve as potential therapeutic targets ranging from pharmacological approaches to gene therapies in CVD. We also discuss multiple factors that influence exercise's effect and highlight the importance and need for further investigations regarding the exercise-regulated molecules as therapeutic targets and biomarkers for CVD as well as the cross talk between the heart and other tissues or organs during exercise. We conclude that a deep understanding of the signaling pathways involved in exercise's benefits for cardiovascular health will undoubtedly contribute to the identification and development of novel therapeutic targets and strategies for CVD.

Multiple Applications of Different Exercise Modalities with Rodents

A large proportion of chronic diseases can be derived from a sedentary lifestyle. Raising physical activity awareness is indispensable, as lack of exercise is the fourth most common cause of death worldwide. Animal models in different research fields serve as important tools in the study of acute or chronic noncommunicable disorders. With the help of animal-based exercise research, exercise-mediated complex antioxidant and inflammatory pathways can be explored, which knowledge can be transferred to human studies. Whereas sustained physical activity has an enormous number of beneficial effects on many organ systems, these animal models are easily applicable in several research areas. This review is aimed at providing an overall picture of scientific research studies using animal models with a focus on different training modalities. Without wishing to be exhaustive, the most commonly used forms of exercise are presented.

New Peptides as Potential Players in the Crosstalk Between the Brain and Obesity, Metabolic and Cardiovascular Diseases

According to the World Health Organization report published in 2016, 650 million people worldwide suffer from obesity, almost three times more than in 1975. Obesity is defined as excessive fat accumulation which may impair health with non-communicable diseases such as diabetes, cardiovascular diseases (hypertension, coronary artery disease, stroke), and some cancers. Despite medical advances, cardiovascular complications are still the leading causes of death arising from obesity. Excessive fat accumulation is caused by the imbalance between energy intake and expenditure. The pathogenesis of this process is complex and not fully understood, but current research is focused on the role of the complex crosstalk between the central nervous system (CNS), neuroendocrine and immune system including the autonomic nervous system, adipose tissue, digestive and cardiovascular systems. Additionally, special attention has been paid to newly discovered substances: neuropeptide 26RFa, preptin, and adropin. It was shown that the above peptides are synthesized both in numerous structures of the CNS and in many peripheral organs and tissues, such as the heart, adipose tissue, and the gastrointestinal tract. Recently, particular attention has been paid to the role of the presented peptides in the pathogenesis of obesity, metabolic and cardiovascular system diseases. This review summarizes the role of newly investigated peptides in the crosstalk between brain and peripheral organs in the pathogenesis of obesity, metabolic, and cardiovascular diseases.

Chinese Soft-Shelled Turtle Oil in Combination With Swimming Training Improves Spatial Memory and Sports Performance of Aging Rats

In this study, waste fat from the Chinese soft-shelled turtle (Pelodiscus sinensis) was used as the raw material, and soft-shelled turtle oil (SSTO) was extracted by water heating. Analysis of the fatty acid composition of SSTO revealed that unsaturated fatty acids (UFAs) comprised more than 70% of the oil, of which more than 20% were omega-3 poly-UFAs. DPPH radical scavenging and cellular ROS assays confirmed the reduction of oxidative stress by SSTO. In D-galactose-induced aging rats, SSTO feeding alone or in combination with swimming training resulted in improved memory and physical strength. In addition, SSTO feeding with swimming intervention significantly increased the SOD level and maintained better blood pressure in the aged rats. The serum DHEAS and soleus muscle glycogen level were also highly correlated with SSTO feeding and swimming training. In conclusion, the results of this study demonstrated that SSTO has the potential to be developed into a health food that exerts anti-aging effects, and those effects are stronger when combined with daily swimming exercise.

Determination of the pathways of potential muscle damage and regeneration in response to acute and long-term swimming exercise in mice

The objective of the current study was examining early and late (3, 24 h) responses to acute, chronic swimming exercise as muscle damage and regeneration in gastrocnemius-soleus muscle complexes. We also aimed to reveal the signaling pathways involved. 8-12 weeks old mice were grouped as control, exercise. Exercising groups were firstly divided into two as acute and chronic, later every group was again divided in terms of time (3, 24 h) passed from the last exercise session until exsanguination. Acute exercise groups swam 30 min, while chronic swimming groups exercised 30 min/day, 5 days/week, 6 weeks. Histological investigations were performed to determine muscle damage and regeneration. Whole-genome expression analysis was applied to total RNA samples. Microarray data was confirmed by quantitative real-time PCR. Exercising mice muscle revealed enhanced damage, leukocyte infiltration. Increments in acute and chronic 3 h groups were statistically significant. Car3, Neb, Obscn, Ttn, Igfbp5, Igfbp7, Gsk3β, and Usp2 were down-regulated in muscles of swimming mice. The exercise-induced signaling pathways involved in muscle damage and regeneration were drawn. Our findings demonstrate that swimming induces muscle damage. Samples were obtained at 3 and 24 h following exercise, this time duration seems not sufficient for the development of myofibrillogenesis.