Long-term moderate intensity exercise alleviates myocardial fibrosis in type 2 diabetic rats via inhibitions of oxidative stress and TGF-β1/Smad pathway

Exercise and dietary interventions in the management of diabetic cardiomyopathy: mechanisms and implications

The global prevalence of diabetes is rapidly increasing, significantly raising the risk of various cardiovascular diseases. Among these, diabetic cardiomyopathy (DCM) is a distinct and critical complication characterized by ventricular hypertrophy and impaired myocardial contractility, ultimately progressing to heart failure and making it a leading cause of mortality among diabetic patients. Despite advances in pharmacological therapies, the effectiveness of managing cardiac dysfunction in DCM remains challenging. Consequently, exploring additional therapeutic strategies for the prevention and treatment of DCM is urgently needed. Beyond pharmacological approaches, lifestyle modifications, particularly exercise and dietary interventions, play a fundamental role in managing DCM due to their significant cardiovascular benefits in diabetic patients. This review synthesizes recent advancements in the field, elucidating the underlying mechanisms through which exercise and dietary interventions influence DCM pathophysiology. By integrating these strategies, we aim to facilitate the development of personalized exercise and dietary regimens that effectively mitigate or prevent DCM progression.

Effects of Dapagliflozin on Myocardial Gene Expression in BTBR Mice with Type 2 Diabetes

BACKGROUND

Dapagliflozin, a sodium-glucose cotransporter 2 (SGLT2) inhibitor, is approved for the treatment of type 2 diabetes, heart failure, and chronic kidney disease. DAPA-HF and DELIVER trial results demonstrate that the cardiovascular protective effect of dapagliflozin extends to non-diabetic patients. Hence, the mechanism-of-action may extend beyond glucose-lowering and is not completely elucidated. We have previously shown that dapagliflozin reduces cardiac hypertrophy, inflammation, fibrosis, and apoptosis and increases ejection fraction in BTBR mice with type 2 diabetes.

METHODS

We conducted a follow-up RNA-sequencing study on the heart tissue of these animals and performed differential expression and Ingenuity Pathway analysis. Selected markers were confirmed by RT-PCR and Western blot.

RESULTS

SGLT2 had negligible expression in heart tissue. Dapagliflozin improved cardiac metabolism by decreasing glycolysis and pyruvate utilization enzymes, induced antioxidant enzymes, and decreased expression of hypoxia markers. Expression of inflammation, apoptosis, and hypertrophy pathways was decreased. These observations corresponded to the effects of dapagliflozin in the clinical trials.

Physical Exercise: A Promising Treatment Against Organ Fibrosis

Fibrosis represents a terminal pathological manifestation encountered in numerous chronic diseases. The process involves the persistent infiltration of inflammatory cells, the transdifferentiation of fibroblasts into myofibroblasts, and the excessive deposition of extracellular matrix (ECM) within damaged tissues, all of which are characteristic features of organ fibrosis. Extensive documentation exists on fibrosis occurrence in vital organs such as the liver, heart, lungs, kidneys, and skeletal muscles, elucidating its underlying pathological mechanisms. Regular exercise is known to confer health benefits through its anti-inflammatory, antioxidant, and anti-aging effects. Notably, exercise exerts anti-fibrotic effects by modulating multiple pathways, including transforming growth factor-β1/small mother decapentaplegic protein (TGF-β1/Samd), Wnt/β-catenin, nuclear factor kappa-B (NF-kB), reactive oxygen species (ROS), microRNAs (miR-126, miR-29a, miR-101a), and exerkine (FGF21, irisin, FSTL1, and CHI3L1). Therefore, this paper aims to review the specific role and molecular mechanisms of exercise as a potential intervention to ameliorate organ fibrosis.

Effects of moderate-intensity aerobic training on cardiac structure and function in type 2 mellitus diabetic rats: Based on echocardiography and speckle tracking

PURPOSE

The present study aimed to evaluate the cardiac function changes using Layer-specific Speckle-tracking echocardiography (LS-STE) induced by Moderate-intensity aerobic training (MIAT) in Type 2 diabetes mellitus (T2DM) rats.

METHODS

Twenty-six rats were divided into four groups: the Control group (Con), the Training control group (CT), the T2DM group (DM), and the T2DM training group (DT). The CT and DT groups underwent an 8 weeks MIAT. Cardiac structure and function were evaluated by echocardiography and LS-STE.

RESULTS

Compared with the Con group, left atrial diameter (LAD), left ventricular end-diastolic diameter(LVEDD), relation wall thickness (RWT), and left ventricular mass (LVM) were significantly higher, and the endo-, mid-, and epi-longitudinal strain (LS), global radial strain (GRS), and endo- and mid-circumferential strain (CS) were significantly lower in DM rats (all p < 0.05). The endo-, mid-, and epi-LS, GRS, endo- and mid-CS were increased in DT rats compared with DM rats (all p < 0.05). Compared with Con rats, CT rats had a significant increase in LVEDD and LVM (all p < 0.05), meanwhile myocardial strains had no significant differences (all p > 0.05).

CONCLUSION

LS-STE was a sensitive method to assess subclinical myocardial changes in T2DM rats. MIAT had the benefit of reversing cardiac systolic subclinical dysfunction in T2DM rats.

Continuous exercise training rescues hippocampal long-term potentiation in the VPA rat model of Autism: Uncovering sex-specific effects

Long-term potentiation (LTP) impairment has been reported in many studies of autistic models. The aim of the present study was to investigate the effects of interval training (IT) and continuous training (CT) exercises on LTP in the hippocampal dentate gyrus (DG) neurons of valproic acid (VPA) rat model of autism. To induce an autism-like model, pregnant rats were injected 500 mg/kg NaVPA (intraperitoneal) on the embryonic day 12.5. IT and CT aerobic exercises started on postnatal day 56 in the offspring. Four weeks after IT and/or CT exercises, the offspring were urethane-anesthetized and placed into a stereotaxic apparatus for surgery, electrode implantation, and field potential recording. In the DG region, excitatory post synaptic potentials (EPSP) slope and population spike (PS) amplitude were measured. Sex differences in LTP were evident for control rats but not for VPA-exposed offspring. LTP was significantly smaller in VPA-exposed male offspring compared with control male rats. In contrast to males, there was no difference between VPA-exposed female offspring and control female rats. Interestingly, we observed a sex difference in the response to exercise between VPA-exposed male and female offspring. CT exercise training (but not IT) increased LTP in VPA-exposed male offspring. Both IT and CT exercise trainings had no effect on intact LTP in VPA-exposed female offspring. Our work suggests that there may be differences in the benefits of exercise interventions based on sex, and CT exercise training could be more beneficial for LTP improvements.

Modulation of the Cardiovascular Risk in Type 1 Diabetic Rats by Endurance Training in Combination with the Prebiotic Xylooligosaccharide

Diabetic cardiomyopathy is a major etiological factor in heart failure in diabetic patients, characterized by mitochondrial oxidative metabolism dysfunction, myocardial fibrosis, and marked glycogen elevation. The aim of the present study is to evaluate the effect of endurance training and prebiotic xylooligosaccharide (XOS) on the activity of key oxidative enzymes, myocardial collagen, and glycogen distribution as well as some serum biochemical risk markers in streptozotocin-induced type 1 diabetic rats. Male Wistar rats (n = 36) were divided into four diabetic groups (n = 9): sedentary diabetic rats on a normal diet (SDN), trained diabetic rats on a normal diet (TDN), trained diabetic rats on a normal diet with an XOS supplement (TD-XOS), and sedentary diabetic rats with an XOS supplement (SD-XOS). The results show that aerobic training managed to increase the enzyme activity of respiratory Complex I and II and the lactate dehydrogenase in the cardiomyocytes of the diabetic rats. Furthermore, the combination of exercise and XOS significantly decreased the collagen and glycogen content. No significant effects on blood pressure, heart rate or markers of inflammation were detected. These results demonstrate the beneficial effects of exercise, alone or in combination with XOS, on the cardiac mitochondrial enzymology and histopathology of diabetic rats.

Swimming alleviates myocardial fibrosis of type II diabetic rats through activating miR-34a-mediated SIRT1/PGC-1α/FNDC5 signal pathway

Myocardial fibrosis can trigger heart failure in diabetic cardiomyopathy (DCM), and irisin, an exercise-induced myokine, may have a beneficial effect on cardiac function. However, the specific molecular mechanism between exercise and irisin in the diabetic heart remains not fully explored. This study aimed to investigate how miR-34a mediates exercise-induced irisin to ameliorate myocardial fibrosis and its underlying mechanisms. Type 2 diabetes mellitus (T2DM) with DCM was induced in adult male rats with high-fat diet and streptozotocin injection. The DCM rats were subjected to swimming (60 min/d) and recombinant irisin (r-irisin, 500 μg/kg/d) interventions for 8 weeks, respectively. Cardiac function, cardiomyocyte structure, myocardial fibrosis and its correlated gene and protein expression were analyzed. Swimming intervention alleviated insulin resistance, myocardial fibrosis, and myocardial hypertrophy, and promoted blood glucose homeostasis in T2DM model rats. This improvement was associated with irisin upregulation and miR-34a downregulation in the myocardium, thus enhancing cardiac function. Similar efficacy was observed via intraperitoneal injection of exogenous recombinant irisin. Inhibition of miR-34a in vivo exhibited an anti-myocardial fibrotic effect by promoting irisin secretion through activating sirtuin 1 (SIRT1)/peroxisome proliferator-activated receptor-gamma coactivator-1α (PGC-1α)/fibronectin type III domain-containing protein 5 (FNDC5) signal pathway and downregulating myocardial fibrosis markers (collagen I, collagen III, and transforming growth factor-β1). Therefore, swimming-induced irisin has the potential therapeutic effect on diabetic myocardial fibrosis through activating the miR-34a-mediated SIRT1/PGC-1α/FNDC5 signal pathway.

Effects of (S)-3,4-DCPG, an mGlu8 receptor agonist, on hippocampal long-term potentiation at perforant pathway-dentate gyrus synapses in prenatal valproic acid-induced rat model of autism

Autism spectrum disorder (ASD) is a pervasive neurodevelopmental condition characterized by social interaction deficits, communication impairments, repetitive behaviors, and sensory sensitivities. While the etiology of ASD is multifaceted, abnormalities in glutamatergic neurotransmission and synaptic plasticity have been implicated. This study investigated the role of metabotropic glutamate receptor 8 (mGlu8) in modulating long-term potentiation (LTP) in a rat model of ASD induced by prenatal valproic acid (VPA) exposure. To induce an animal model with autism-like characteristics, pregnant rats received an intraperitoneal injection of 500 mg/kg of sodium valproate (NaVPA) on embryonic day 12.5. High-frequency stimulation was applied to the perforant path-dentate gyrus (PP-DG) synapse to induce LTP, while the mGlu8 receptor agonist (S)-3,4-dicarboxyphenylglycine (DCPG) was administered into the DG. The results revealed that VPA-exposed rats exhibited reduced LTP compared to controls. DCPG had contrasting effects, inhibiting LTP in controls and enhancing it in VPA-exposed rats. Moreover, reduced social novelty preference index (SNPI) in VPA-exposed rats was reversed by intra-DG administration of S-3,4-DCPG. In conclusion, our study advances our understanding of the complex relationship between glutamatergic neurotransmission, synaptic plasticity, and VPA-induced autism model. The findings suggest that mGlu8 receptor dysfunction plays a role in the impaired synaptic plasticity seen in ASD.

Endurance Exercise Prevented Diabetic Cardiomyopathy through the Inhibition of Fibrosis and Hypertrophy in Rats

Background

Exercise training could be essential in preventing pathological cardiac remodeling in diabetes. Therefore, the effects of moderate-intensity continuous training (MICT) and high-intensity interval training (HIIT) singly or plus metformin on diabetes-induced cardiomyopathy were investigated in this study.

Methods

Forty-nine Wistar rats (male) were recruited. Seven groups of animals were treated for six weeks as control, diabetes, MICT (15 m/min, 40 min/day), HIIT (20 m/min, 40 min/day), metformin (300 mg/kg), HIIT+metformin (Met-HIIT), and MICT+metformin (Met-MICT). The metformin was orally administered with an intragastrical needle, and the exercised rats were trained (5 days/week) with a motorized treadmill. Metabolic parameters, echocardiographic indices, histopathology evaluation, and assessment of gene expression connected with cardiac fibrosis, hypertrophy, mitochondrial performance, and intracellular calcium homeostasis were investigated.

Results

Our results demonstrated that all the interventions prevented weight loss and enhanced heart weight/body weight ratio and fasting plasma glucose in diabetic rats. Both types of exercise and their metformin combinations improved diabetic animals' echocardiography indices by enhancing heart rate, fractional shortening (FS), ejection fraction (EF) and reducing end-systolic and end-diastolic diameter of left ventricular (LVESD and LVEDD). Gene expression of atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP), transforming growth factor (TGF)- β , and collagen increased in the diabetes group. In contrast, the gene expression of peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC-1 α ), AMP-activated protein kinase (AMPK), ryanodine receptors (RyR), and Ca 2 + ATPase pump of the sarcoplasmic reticulum (SERCA) was reduced in diabetic animals. Exercise training alone or in combination with metformin reversed these changes. Moreover, diabetes-induced cardiac fibrosis was ameliorated in treated groups. All indicators of diabetic cardiomyopathy were improved more in the Met-HIIT group than in other groups.

Conclusions

Exercise training, notably with metformin combination, alleviated diabetes-induced cardiac complications. The beneficial effects of exercise could be related to improving pathological cardiac remodeling and enhancing cardiac function.

Intrinsic and Extrinsic Contributors to the Cardiac Benefits of Exercise

Among its many cardiovascular benefits, exercise training improves heart function and protects the heart against age-related decline, pathological stress, and injury. Here, we focus on cardiac benefits with an emphasis on more recent updates to our understanding. While the cardiomyocyte continues to play a central role as both a target and effector of exercise's benefits, there is a growing recognition of the important roles of other, noncardiomyocyte lineages and pathways, including some that lie outside the heart itself. We review what is known about mediators of exercise's benefits-both those intrinsic to the heart (at the level of cardiomyocytes, fibroblasts, or vascular cells) and those that are systemic (including metabolism, inflammation, the microbiome, and aging)-highlighting what is known about the molecular mechanisms responsible.

The effects of carvacrol and p-cymene on Aβ1-42 -induced long-term potentiation deficit in male rats

AIMS

Alzheimer's disease (AD) is the most common type of dementia in which oxidative stress plays an important role. In this disease, learning and memory and the cellular mechanism associated with it, long-term potentiation (LTP), are impaired. Considering the beneficial effects of carvacrol (CAR) and p-cymene against AD, their effect was assessed on in vivo hippocampal LTP in the perforant pathway (PP)-dentate gyrus (DG) pathway in an Aβ1-42 -induced rat model of AD.

METHODS

Male Wistar rats were randomly assigned to five groups: sham: intracerebroventricular (ICV) injection of phosphate-buffered saline, Aβ: ICV Aβ1-42 injections, Aβ + CAR (50 mg/kg), Aβ + p-cymene (50 mg/kg), and Aβ + CAR + p-cymene. Administration of CAR and p-cymene was done by gavage daily 4 weeks before and 4 weeks after the Aβ injection. The population spike (PS) amplitude and field excitatory postsynaptic potentials (fEPSP) slope were determined in DG against the applied stimulation to the PP.

RESULTS

Aβ-treated rats exhibited impaired LTP induction in the PP-DG synapses, resulting in significant reduction in both fEPSP slope and PS amplitude compared to the sham animals. Aβ-treated rats consumed either CAR or p-cymene separately (but not their combination), and showed an enhancement in fEPSP slope and PS amplitude of the DG granular cells.

CONCLUSIONS

These data indicate that CAR or p-cymene can ameliorate Aβ-associated changes in synaptic plasticity. Surprisingly, the combination of CAR and p-cymene did not yield the same effect, suggesting a potential interaction between the two substances.

Effect of exercise on improving myocardial mitochondrial function in decreasing diabetic cardiomyopathy

Diabetic cardiomyopathy (DCM) is a significant cause of heart failure in patients with diabetes, and its pathogenesis is closely related to myocardial mitochondrial injury and functional disability. Studies have shown that the development of diabetic cardiomyopathy is related to disorders in mitochondrial metabolic substrates, changes in mitochondrial dynamics, an imbalance in mitochondrial Ca2+ regulation, defects in the regulation of microRNAs, and mitochondrial oxidative stress. Physical activity may play a role in resistance to the development of diabetic cardiomyopathy by improving myocardial mitochondrial biogenesis, the level of autophagy and dynamic changes in fusion and division; enhancing the ability to cope with oxidative stress; and optimising the metabolic substrates of the myocardium. This paper puts forward a new idea for further understanding the specific mitochondrial mechanism of the occurrence and development of diabetic cardiomyopathy and clarifying the role of exercise-mediated myocardial mitochondrial changes in the prevention and treatment of diabetic cardiomyopathy. This is expected to provide a new theoretical basis for exercise to reduce diabetic cardiomyopathy symptoms.

Moderate-Intensity and High-Intensity Interval Exercise Training Offer Equal Cardioprotection, with Different Mechanisms, during the Development of Type 2 Diabetes in Rats

Endurance exercise training is a promising cardioprotective strategy in type 2 diabetes mellitus (T2DM), but the impact of its intensity is not clear. We aimed to investigate whether and how isocaloric moderate-intensity exercise training (MIT) and high-intensity interval exercise training (HIIT) could prevent the adverse cardiac remodeling and dysfunction that develop T2DM in rats. Male rats received a Western diet (WD) to induce T2DM and underwent a sedentary lifestyle (n = 7), MIT (n = 7) or HIIT (n = 8). Insulin resistance was defined as the HOMA-IR value. Cardiac function was assessed with left ventricular (LV) echocardiography and invasive hemodynamics. A qPCR and histology of LV tissue unraveled underlying mechanisms. We found that MIT and HIIT halted T2DM development compared to in sedentary WD rats (p < 0.05). Both interventions prevented increases in LV end-systolic pressure, wall thickness and interstitial collagen content (p < 0.05). In LV tissue, HIIT tended to upregulate the gene expression of an ROS-generating enzyme (NOX4), while both modalities increased proinflammatory macrophage markers and cytokines (CD86, TNF-α, IL-1β; p < 0.05). HIIT promoted antioxidant and dicarbonyl defense systems (SOD2, glyoxalase 1; p < 0.05) whereas MIT elevated anti-inflammatory macrophage marker expression (CD206, CD163; p < 0.01). We conclude that both MIT and HIIT limit WD-induced T2DM with diastolic dysfunction and pathological LV hypertrophy, possibly using different adaptive mechanisms.

Diabetic cardiomyopathy in rats was attenuated by endurance exercise through the inhibition of inflammation and apoptosis

Diabetic cardiomyopathy (DCM), as a ventricular dysfunction, is one of the main causes of death in diabetic patients. Former evidence revealed the beneficial effects of exercise on cardiovascular complications of diabetes. We aimed to investigate the effects of high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) on DCM. Male Wistar rats were divided into control, diabetic, metformin (300 mg/kg), HIIT, MICT, metformin + HIIT, and metformin + MICT diabetic groups. Serum biochemical, inflammatory, and oxidative stress indicators, gene expression of BCL2 and BAX, and histopathologic changes of cardiac tissue were assessed. Our analysis revealed an increase in fasting blood sugar (FBS), creatine kinase MB (CK-MB), lactate dehydrogenase (LDH), and aspartate aminotransferase (AST) in diabetes. Also, the superoxide dismutase (SOD) and catalase (CAT) activity, and the total thiol were decreased, in contrast, malondialdehyde (MDA) levels increased in the cardiac tissue of the diabetic group. All of these changes were significantly ameliorated in diabetic animals treated with exercise and metformin + exercise. The level of tumor necrosis factor-α (TNF-α) and Interleukin-1β (IL-1β), as well as the infiltration of inflammatory cells, were decreased in the heart of all exercise training groups. Up-regulation of BCL2 and down-regulation of BAX gene expressions were observed in the cardiac tissue of all exercise-treated groups. In conclusion, HIIT and MICT exercises are effective in preventing DCM development. Exercise training, besides improving oxidative stress and inflammation in cardiac tissue, alleviates cardiac damage by modulating the apoptotic gene expression in diabetic rats.

Moderate- and High-Intensity Endurance Training Alleviate Diabetes-Induced Cardiac Dysfunction in Rats

Exercise training is an encouraging approach to treat cardiac dysfunction in type 2 diabetes (T2DM), but the impact of its intensity is not understood. We aim to investigate whether and, if so, how moderate-intensity training (MIT) and high-intensity interval training (HIIT) alleviate adverse cardiac remodeling and dysfunction in rats with T2DM. Male rats received standard chow (n = 10) or Western diet (WD) to induce T2DM. Hereafter, WD rats were subjected to a 12-week sedentary lifestyle (n = 8), running MIT (n = 7) or HIIT (n = 7). Insulin resistance and glucose tolerance were assessed during the oral glucose tolerance test. Plasma advanced glycation end-products (AGEs) were evaluated. Echocardiography and hemodynamic measurements evaluated cardiac function. Underlying cardiac mechanisms were investigated by histology, western blot and colorimetry. We found that MIT and HIIT lowered insulin resistance and blood glucose levels compared to sedentary WD rats. MIT decreased harmful plasma AGE levels. In the heart, MIT and HIIT lowered end-diastolic pressure, left ventricular wall thickness and interstitial collagen deposition. Cardiac citrate synthase activity, mitochondrial oxidative capacity marker, raised after both exercise training modalities. We conclude that MIT and HIIT are effective in alleviating diastolic dysfunction and pathological cardiac remodeling in T2DM, by lowering fibrosis and optimizing mitochondrial capacity.

Emodin attenuates diabetic kidney disease by inhibiting ferroptosis via upregulating Nrf2 expression

Diabetic kidney disease (DKD) poses a threat to people's health. The current treatments only provide partial relief of symptoms. Therefore, seeking a promising therapeutic medication for the prevention and control on DKD will benefit patients. Recently, a novel iron-dependent and non-apoptotic regulated mode of cell death, termed as ferroptosis, is expected to offer us a novel insight into the mechanism of DKD. We conducted experiments to investigate the role of ferroptosis in the development of DKD. Iron accumulation, weakened antioxidant capacity and ROS overproduction were observed in the renal tissues of STZ-induced diabetic rats. A persistent high glucose condition contributed to down regulated levels of Glutathione Peroxidase 4 (GPX4) and Solute Carrier Family 7 Member 11 (SLC7A11) which marked the occurrence of ferroptosis. Treatment of Emodin in DKD models could significantly attenuated these changes and reduced renal injury. Besides, NFE2-related factor 2 (Nrf2), an important antioxidant regulator, was inhibited in both in vivo and in vitro assay, which contributes to Reactive Oxygen Species (ROS) generation that further promoted the expression of ferroptosis related protein. These unwanted effects were offset by the intervention of Emodin. The specific Nrf2 knock out enhanced cell's sensitivity to ferroptosis by being exposed to high glucose culture, which was improved by treatment of Emodin via restoring activity of Nrf2. In conclusion, our research demonstrated that Emodin exerted renal protection against DKD via inhibiting ferroptosis and restoring Nrf2 mediated antioxidant capacity, which could be employed as a novel therapeutic medication against DKD.

2-Arachidonoylglycerol Attenuates Myocardial Fibrosis in Diabetic Mice Via the TGF-β1/Smad Pathway

PURPOSE

Diabetic cardiomyopathy (DM) is the cause of late cardiac dysfunction in diabetic patients. Myocardial fibrosis is the main pathological mechanism, and it is associated with transforming growth factor-β1(TGF-β1) expression up-regulation. 2-Arachidonoylglycerol (2-AG) is an endogenous cannabinoid that can effectively improve myocardial cell energy metabolism and cardiac function. Here, we evaluated the protective effect of 2-AG on diabetic cardiomyopathy.

METHODS

Male C57BL/6 mice were injected with 2-AG intraperitoneally for 4 weeks (10 micro g/kg/day) after 12 weeks of diabetic modeling. After 4 weeks, heart function was evaluated by echocardiography. Heart structure was assessed by hematoxylin and eosin staining. Cardiac fibrosis was analyzed using immunohistochemistry, Sirius red stain, and western blot.

RESULTS

After modeling in diabetic mice, cardiac ultrasonography showed decreased cardiac function and pathological findings showed myocardial fibrosis. 2-AG could effectively inhibit the up-regulation of TGF-β1 and Smad2/3, reduce myocardial fibrosis, and ultimately improve cardiac function in diabetic mice.

CONCLUSION

2-AG reduces cardiac fibrosis via the TGF-β1/Smad2/3 pathway and is a potential pathway for the treatment of cardiac dysfunction in diabetic mice.

Progress in the Mechanism of the Effect of Fe3O4 Nanomaterials on Ferroptosis in Tumor Cells

Ferroptosis is a new form of iron-dependent programmed cell death discovered in recent years, which is caused by the accumulation of lipid peroxidation (LPO) and reactive oxygen species (ROS). Recent studies have shown that cellular ferroptosis is closely related to tumor progression, and the induction of ferroptosis is a new means to inhibit tumor growth. Biocompatible Fe₃O₄ nanoparticles (Fe₃O₄-NPs), rich in Fe²⁺ and Fe³⁺, act as a supplier of iron ions, which not only promote ROS production but also participate in iron metabolism, thus affecting cellular ferroptosis. In addition, Fe₃O₄-NPs combine with other techniques such as photodynamic therapy (PDT); heat stress and sonodynamic therapy (SDT) can further induce cellular ferroptosis effects, which then enhance the antitumor effects. In this paper, we present the research progress and the mechanism of Fe₃O₄-NPs to induce ferroptosis in tumor cells from the perspective of related genes and chemotherapeutic drugs, as well as PDT, heat stress, and SDT techniques.

Effects of sesamin on Aβ1-42-induced oxidative stress and LTP impairment in a rat model of Alzheimer's disease

The present study examined the protective effect of sesamin (Ses) on β-amyloid (Aβ)-induced long-term potentiation (LTP) impairment at the PP-DG synapses in male rats. Wistar rats were randomly assigned to seven groups: control, sham, Aβ; ICV Aβ_1-42 microinjection, Ses, Aβ + Ses; first, ICV Aβ injections and then receiving Ses, Ses + Aβ: four weeks of pretreatment with Ses and then Aβ injection, and Ses + Aβ + Ses: pre (four weeks) and post (four weeks) treatment with Ses. Ses-treated groups received 30 mg/kg of Ses once a day by oral gavage for four weeks. After the treatment period, the animals were positioned in a stereotaxic device for surgery and field potential recording. The population spike (PS) amplitude and slope of excitatory postsynaptic potentials (EPSP) were evaluated in the DG region. Serum oxidative stress biomarkers (total oxidant status (TOS) and total antioxidant capacity (TAC)) were measured. Aβ impaired LTP induction at the PP-DG synapses evidenced by a decrease in EPSP slope and PS amplitude of LTP. In Aβ rats, Ses increased EPSP slope and PS amplitude of LTP in the DG granular cells. Also, an increase in TOS and a reduction in TAC caused by Aβ were significantly corrected by Ses. Ses could prevent Aβ-induced LTP impairment at the PP-DG synapses in male rats, which can be due to its preventive effects on oxidative stress.

Moderate-Intensity Exercise Maintains Redox Homeostasis for Cardiovascular Health

It is well known that exercise is beneficial for cardiovascular health. Oxidative stress is the common pathological basis of many cardiovascular diseases. The overproduction of free radicals, both reactive oxygen species and reactive nitrogen species, can lead to redox imbalance and exacerbate oxidative damage to the cardiovascular system. Maintaining redox homeostasis and enhancing anti-oxidative capacity are critical mechanisms by which exercise protects against cardiovascular diseases. Moderate-intensity exercise is an effective means to maintain cardiovascular redox homeostasis. Moderate-intensity exercise reduces the risk of cardiovascular disease by improving mitochondrial function and anti-oxidative capacity. It also attenuates adverse cardiac remodeling and enhances cardiac function. This paper reviews the primary mechanisms of moderate-intensity exercise-mediated redox homeostasis in the cardiovascular system. Exploring the role of exercise-mediated redox homeostasis in the cardiovascular system is of great significance to the prevention and treatment of cardiovascular diseases.

Anti-apoptotic and anti-fibrotic efficacy of exercise training in hypertensive hearts: A systematic review

Background

This review aims to summarize the antiapoptotic, pro-survival, and antifibrotic effects of exercise training in hypertensive hearts.

Methods

Keyword searches were conducted in PubMed, Web of Science, and Scopus in May 2021. Research published in English on the effects of exercise training on the apoptosis, survival, and fibrosis pathways in hypertension was included. The CAMARADES checklist was used to determine the quality of the studies. Two reviewers independently implemented predesigned protocols for the search and selection of studies, the assessment of study quality, and the evaluation of the strength of evidence.

Results

Eleven studies were included after selection. The duration of the exercise training ranged from 5 to 27 weeks. Nine studies showed that exercise training improved cardiac survival rates by increasing IGF-1, IGF-1 receptor, p-PI3K, Bcl-2, HSP 72, and p-Akt. Furthermore, 10 studies showed that exercise training reduced apoptotic pathways by downregulating Bid, t-Bid, Bad, Bak, Bax, TNF, and FADD. Finally, two studies reported the modification and subsequent improvement of physiological characteristics of fibrosis and decreased MAPK p38 and PTEN levels by exercise training in the left ventricle of the heart.

Conclusions

The findings of the review showed that exercise training could improve cardiac survival rates and attenuate cardiac apoptotic and fibrotic pathways in hypertension, suggesting that exercise training could act as a therapeutic approach to prevent hypertension-induced cardiac apoptosis and fibrosis.

Systematic Review Registration

https://www.crd.york.ac.uk, identifier: CRD42021254118.

Beyond cardiomyocytes: Cellular diversity in the heart's response to exercise

Cardiomyocytes comprise ∼70% to 85% of the total volume of the adult mammalian heart but only about 25% to 35% of its total number of cells. Advances in single cell and single nuclei RNA sequencing have greatly facilitated investigation into and increased appreciation of the potential functions of non-cardiomyocytes in the heart. While much of this work has focused on the relationship between non-cardiomyocytes, disease, and the heart's response to pathological stress, it will also be important to understand the roles that these cells play in the healthy heart, cardiac homeostasis, and the response to physiological stress such as exercise. The present review summarizes recent research highlighting dynamic changes in non-cardiomyocytes in response to the physiological stress of exercise. Of particular interest are changes in fibrotic pathways, the cardiac vasculature, and immune or inflammatory cells. In many instances, limited data are available about how specific lineages change in response to exercise or whether the changes observed are functionally important, underscoring the need for further research.

Decreased inflammatory gene expression accompanies the improvement of liver enzyme and lipid profile following aerobic training and vitamin D supplementation in T2DM patients

BACKGROUND

Type 2 Diabetes Mellitus (T2DM) is one of the health issues causing untoward low-grade systemic inflammation. Aerobic Training (AT) and Vitamin D (Vit D) supplementation are among the approaches that improve lipid profile and liver enzymes in T2DM. However, the mechanisms responsible for these improvements are not fully elucidated.

OBJECTIVES

This study aimed to evaluate the effects of AT and Vit D supplementation on lipid profile, liver enzymes, Interleukin-6 (IL-6), Interleukin-10 (IL-10), Cluster of differentiation 27 (CD27), Chemokine (C-X-C motif) Ligand 13 (CXCL13), Interferon-Gamma (IFN-γ) and Transforming Growth Factor-Beta 1 (TGF-β1) gene expressions in patients with T2DM.

METHODS

In this study, 40 male T2DM patients aged 35-50 years were randomly selected and assigned into four groups (n = 10 for each); AT+vitamin D supplementation (AT+Vit D), AT+placebo (AT), Vit D supplementation (Vit D), and control+placebo (C). The intervention consisted of 8 weeks of 20-40 minutes AT protocol at 60-75% HR_max 3 sessions/week and taking 50,000 IU of Vit D supplement once a week. Serum levels of lipid profile and liver enzymes and gene expression of IL-6, IL-10, CD27, CXCL13, IFN-γ, and TGF-β1 in Peripheral Blood Mononuclear Cells (PBMCs) were measured. One-way analysis of variance (ANOVA), Tukey's post hoc, and paired sample t-test at P-values less than 0.05 were used to analyze the data using SPSS software.

RESULTS

AT+Vit D, AT, and Vit D significantly decreased TC, TG, LDL, AST, ALT, and GGT while increased HDL after 8 weeks in favor of AT+Vit D. Also, gene expressions of IL-6, IL-10, CD27, CXCL13, IFN-γ, and TGF-β1 were downregulated significantly in AT+Vit D, AT, and Vit D, while upregulated in C. Furthermore, compared to individual AT or Vit D, AT+Vit D significantly downregulated IL-6 (P = 0.013; P = 0.025), IL-10 (P = 0.012; P = 0.026), CD27 (P = 0.023; P = 0.041), CXCL13 (P = 0.014; P = 0.025), IFN-γ (P = 0.017; P = 0.026), and TGF-β1 (P = 0.001; P = 0.028).

CONCLUSION

In comparison to individual AT or Vit D, AT+Vit D may enhance lipid profile, and liver enzymes and drive the balance to favor inhibition of inflammation by downregulating gene expression of inflammation-related factors. As a result, AT+Vit D may be considered appropriate therapy for managing T2DM.

Impairment in social interaction and hippocampal long-term potentiation at perforant pathway-dentate gyrus synapses in a prenatal valproic acid-induced rat model of autism

It is well established that prenatal valproic acid exposure in rats leads to autism-like behaviours and social deficits. Long-term potentiation changes in the brain have been proposed as a potential mechanism in the development of autistic behaviour. However, there are controversies regarding the effect of in utero valproic acid exposure on long-term potentiation. This study examined the social interaction and long-term potentiation induction in perforant pathway-dentate gyrus synapses in male offspring of a rat model of autism induced by prenatal exposure to valproic acid. On Embryonic Day 12.5, the pregnant dams received an injection of 500 mg/kg valproic acid (intraperitoneal) to produce the autism model. The sociability test was performed between Postnatal Days 37 and 40. The offsprings were urethane-anaesthetized and placed into a stereotaxic apparatus for surgery, electrode implantation and field potential recording on Postnatal Days 45–55. In the dentate gyrus region, excitatory postsynaptic potential slope and population spike amplitude were measured. Valproic acid-exposed offspring showed significantly impaired social interaction. The birth weight in valproic acid-exposed rats was significantly lower than in control rats. The ability of dentate gyrus synapses to induce long-term potentiation was hampered by valproic acid exposure. The decreasing excitatory postsynaptic potential slope and population spike amplitude of long-term potentiation provide evidence in favour of this notion. It is widely supposed that the hippocampus plays a central role in the process of learning and memory as well as social interaction and social memory. Therefore, deficiencies in hippocampal synaptic plasticity may be responsible, at least in part, for the social interaction deficits in valproic acid-exposed rats.

Alpha-lipoic acid treatment improves adverse cardiac remodelling in the diabetic heart - The role of cardiac hydrogen sulfide-synthesizing enzymes

INTRODUCTION

Alpha-lipoic acid (ALA) is a licensed drug for the treatment of diabetic neuropathy. We recently reported that it also improves diabetic cardiomyopathy (DCM) in type 2 diabetes mellitus (T2DM). In this study, we present evidence supporting our hypothesis that the cardioprotective effect of ALA is via upregulation of cardiac hydrogen sulfide (H₂S)-synthesizing enzymes.

METHODS

Following 12 h of overnight fasting, T2DM was induced in 23 out of 30 male Sprague-Dawley rats by intraperitoneal administration of nicotinamide (110 mg/kg) followed by streptozotocin (55 mg/kg) while the rest served as healthy control (HC). T2DM rats then received either oral administration of ALA (60 mg/kg/day; n = 7) or 40 mg/kg/day DL-propargylglycine (PAG, an endogenous H₂S inhibitor; n = 7) intraperitoneally for 6 weeks after which all rats were sacrificed and samples collected for analysis. Untreated T2DM rats served as diabetic control (DCM; n = 9).

RESULTS

T2DM resulted in weight loss, islet destruction, reduced pancreatic β-cell function and hyperglycemia. Histologically, DCM rats showed significant myocardial damage evidenced by myocardial degeneration, cardiomyocyte vacuolation and apoptosis, cardiac fibrosis and inflammation, which positively correlated with elevated levels of cardiac damage markers compared to HC rats (p < 0.001). These pathological alterations worsened significantly in PAG-treated rats (p < 0.05). However, ALA treatment restored normoinsulemia, normoglycemia, prevented DCM, and improved lipid and antioxidant status. Mechanistically, ALA significantly upregulated the expression of cardiac H₂S-synthesizing enzymes and increased plasma H₂S concentration compared to DCM rats (p < 0.001).

CONCLUSION

ALA preserves myocardial integrity in T2DM likely by maintaining the expression of cardiac H₂S-synthezing enzymes and increasing plasma H₂S level.

Aerobic Exercise Inhibited P2X7 Purinergic Receptors to Improve Cardiac Remodeling in Mice With Type 2 Diabetes

Background: Diabetic cardiomyopathy (DCM), the main complication of diabetes mellitus, presents as cardiac dysfunction by ventricular remodeling. In addition, the inhibition of P2X7 purinergic receptors (P2X7R) alleviates cardiac fibrosis and apoptosis in Type 1 diabetes. However, whether exercise training improves cardiac remodeling by regulating P2X7R remains unknown. Methods: Db/db mice spontaneously induced with type 2 diabetes and high-fat diet (HFD) and mice with streptozotocin (STZ)-induced type 2 diabetes mice were treated by 12-week treadmill training. Cardiac functions were observed by two-dimensional echocardiography. Hematoxylin-eosin staining, Sirius red staining and transmission electron microscopy were respectively used to detect cardiac morphology, fibrosis and mitochondria. In addition, real-time polymerase chain reaction and Western Blot were used to detect mRNA and protein levels. Results: Studying the hearts of db/db mice and STZ-induced mice, we found that collagen deposition and the number of disordered cells significantly increased compared with the control group. However, exercise markedly reversed these changes, and the same tendency was observed in the expression of MMP9, COL-I, and TGF-β, which indicated cardiac fibrotic and hypertrophic markers, including ANP and MyHC expression. In addition, the increased Caspase-3 level and the ratio of Bax/Bcl2 were reduced by exercise training, and similar results were observed in the TUNEL test. Notably, the expression of P2X7R was greatly upregulated in the hearts of db/db mice and HFD + STZ-induced DM mice and downregulated by aerobic exercise. Moreover, we indicated that P2X7R knock out significantly reduced the collagen deposition and disordered cells in the DM group. Furthermore, the apoptosis levels and TUNEL analysis were greatly inhibited by exercise or in the P2X7R^-/- group in DM. We found significant differences between the P2X7R^-/- + DM + EX group and DM + EX group in myocardial tissue apoptosis and fibrosis, in which the former is significantly milder. Moreover, compared with the P2X7R^-/- + DM group, the P2X7R^-/- + DM + EX group represented a lower level of cardiac fibrosis. The expression levels of TGF-β at the protein level and TGF-β and ANP at the genetic level were evidently decreased in the P2X7R^-/- + DM + EX group. Conclusion: Aerobic exercise reversed cardiac remodeling in diabetic mice at least partly through inhibiting P2X7R expression in cardiomyocytes.

Animal Models of Exercise From Rodents to Pythons

Acute and chronic animal models of exercise are commonly used in research. Acute exercise testing is used, often in combination with genetic, pharmacological, or other manipulations, to study the impact of these manipulations on the cardiovascular response to exercise and to detect impairments or improvements in cardiovascular function that may not be evident at rest. Chronic exercise conditioning models are used to study the cardiac phenotypic response to regular exercise training and as a platform for discovery of novel pathways mediating cardiovascular benefits conferred by exercise conditioning that could be exploited therapeutically. The cardiovascular benefits of exercise are well established, and, frequently, molecular manipulations that mimic the pathway changes induced by exercise recapitulate at least some of its benefits. This review discusses approaches for assessing cardiovascular function during an acute exercise challenge in rodents, as well as practical and conceptual considerations in the use of common rodent exercise conditioning models. The case for studying feeding in the Burmese python as a model for exercise-like physiological adaptation is also explored.

Downregulated hs-CRP and MAD, upregulated GSH and TAC, and improved metabolic status following combined exercise and turmeric supplementation: a clinical trial in middle-aged women with hyperlipidemic type 2 diabetes

Background

Aerobic training (AT) and Turmeric Supplementation (TS) are known to exert multiple beneficial effects including metabolic status and Oxidative Stress. To our knowledge, data on the effects of AT and TS on metabolic status and oxidative stress biomarkers related to inflammation in subjects with Hyperlipidemic Type 2 Diabetes Mellitus (HT2DM) are scarce.

Objectives

This study was conducted to evaluate the effects of AT and TS on metabolic status and oxidative stress biomarkers related to inflammation in subjects with HT2DM.

Methods

This randomized single-blinded, placebo-controlled trial was conducted among 42 subjects with HT2DM, aged 45-60 years old. Participants were randomly assigned to four groups; AT+TS (n = 11), AT+placebo (AT; n = 10), TS (n = 11), and Control+placebo (C; n = 10). The AT program consisted of 60-75% of Maximum heart rate (HRmax), 20-40 min/day, three days/week for eight weeks. The participants in the TS group consumed three 700 mg capsules/day containing turmeric powder for eight weeks. Metabolic status and oxidative stress biomarkers were assessed at baseline and end of treatment. The data were analyzed through paired t-test and one-way analysis of variance (ANOVA) and Bonferroni post hoc test at the signification level of P < 0.05.

Results

After eight weeks, significant improvements were observed in metabolic status, oxidative stress biomarkers and high-sensitivity C-reactive protein (hs-CRP) in the AT+TS, TS, and AT compared to C. Additionally, a significant decrease of Metabolic Syndrome (MetS) Z scores (p = 0.001; p = 0.011), hs-CRP (p = 0.028; p = 0.041), Malondialdehyde (MAD) (p = 0.023; p = 0.001), and significantly higher Glutathione (GSH) (p = 0.003; p = 0.001), and Total Antioxidant Capacity (TAC) (p = 0.001; p = 0.001) compared to the AT and TS groups. The results also revealed a significant difference in terms of MetS Z scores (p = 0.001), hs-CRP (p = 0.018), MAD (p = 0.011), GSH (p = 0.001) and TAC (p = 0.025) between the AT and TS.

Conclusions

The findings suggest that AT+TS improves metabolic status, oxidative stress biomarkers, and hs-CRP more effectively compared to TS or AT in middle-aged females with T2DM and hyperlipidemia.

DNA Templated Silver Nanoclusters for Bioanalytical Applications: A Review

Due to their unique programmability, biocompatibility, photostability and high fluorescent quantum yield, DNA templated silver nanoclusters (DNA Ag NCs) have attracted increasing attention for bioanalytical application. This review summarizes the recent developments in fluorescence properties of DNA templated Ag NCs, as well as their applications in bioanalysis. Finally, we herein discuss some current challenges in bioanalytical applications, to promote developments of DNA Ag NCs in biochemical analysis.

Combination Therapy of Alpha-Lipoic Acid, Gliclazide and Ramipril Protects Against Development of Diabetic Cardiomyopathy via Inhibition of TGF-β/Smad Pathway

Background: Diabetic cardiomyopathy (DCM) is a major long-term complication of diabetes mellitus, accounting for over 20% of annual mortality rate of diabetic patients globally. Although several existing anti-diabetic drugs have improved glycemic status in diabetic patients, prevalence of DCM is still high. This study investigates cardiac effect of alpha-lipoic acid (ALA) supplementation of anti-diabetic therapy in experimental DCM. Methods: Following 12 h of overnight fasting, 44 male Sprague Dawley rats were randomly assigned to two groups of healthy control (n = 7) and diabetic (n = 37) groups, and fasting blood glucose was measured. Type 2 diabetes mellitus (T2DM) was induced in diabetic group by intraperitoneal (i.p.) administration of nicotinamide (110 mg/kg) and streptozotocin (55 mg/kg). After confirmation of T2DM on day 3, diabetic rats received monotherapies with ALA (60 mg/kg; n = 7), gliclazide (15 mg/kg; n = 7), ramipril (10 mg/kg; n = 7) or combination of the three drugs (n = 7) for 6 weeks while untreated diabetic rats received distilled water and were used as diabetic control (n = 9). Rats were then sacrificed, and blood, pancreas and heart tissues were harvested for analyses using standard methods. Results: T2DM induction caused pancreatic islet destruction, hyperglycemia, weight loss, high relative heart weight, and development of DCM, which was characterized by myocardial degeneration and vacuolation, cardiac fibrosis, elevated cardiac damage markers (plasma and cardiac creatine kinase-myocardial band, brain natriuretic peptide and cardiac troponin I). Triple combination therapy of ALA, gliclazide and ramipril preserved islet structure, maintained body weight and blood glucose level, and prevented DCM development compared to diabetic control (p < 0.001). In addition, the combination therapy markedly reduced plasma levels of inflammatory markers (IL-1β, IL-6 and TNF-α), plasma and cardiac tissue malondialdehyde, triglycerides and total cholesterol while significantly increasing cardiac glutathione and superoxide dismutase activity and high-density lipoprotein-cholesterol compared to diabetic control (p < 0.001). Mechanistically, induction of T2DM upregulated cardiac expression of TGF-β1, phosphorylated Smad2 and Smad3 proteins, which were downregulated following triple combination therapy (p < 0.001). Conclusion: Triple combination therapy of ALA, gliclazide and ramipril prevented DCM development by inhibiting TGF-β1/Smad pathway. Our findings can be extrapolated to the human heart, which would provide effective additional pharmacological therapy against DCM in T2DM patients.

Research on Mechanism of Nanometric Bone Pulp Activated with Double Gene as Bone Morphogenetic Protein 1 and Vascular Endothelial Growth Factor for Improving the Strength of Centrum in Osteoporosis

The aim of this study was assessing the mechanism of nanometric bone pulp activated with double gene as bone morphogenetic protein 1 (BMP-1) and vascular endothelial growth factor (VEGF) in improving the strength of centrum in osteoporosis (OP). The model of nanometric bone pulp activated with BMP-1 and VEGF double gene was established and validated. Under maximum condition of load and collapsed fragments, the model was analyzed through biomechanical test. The conditions for ALP, BGP, MLL and BMD in the model were also analyzed, and three-dimensional structural transformation was analyzed. Western blot and qRT-PCR were used to detect the effect of adding or not adding dual gene activated nano-bone stickers on OC-specific protein and mRNA; ELISA kits were used to detect the changes of RANKL pathway RANKL, OPG and TRACP5b. The maximum conformed quality and condensed intensity were strengthened with the nanometric bone pulp activated with BMP-1 and VEGF double gene. The maximum load in centrum was extremely elevated in the model, and the condition of ALP and its effect on bone was partly improved in the model. The precision and efficiency in the quality of BMD were continuously decreased. The BMD and MLF were strengthened notably in the model, and their effect on the bone was extremely improved. There was tight displayed model of trabecular in centrum and porosity was also continuously reduced. After adding the double-gene activated nano-bone stickers, the results from qRTPCR and Western blot showed that the changes of osteoclast-related genes and protein expressions were significantly down-regulated. The nanometric bone pulp activated with BMP-1 and VEGF double gene was one of ideal filled criterion. The BMD and bone strength were also elevated.

Liuwei Dihuang Pill Attenuates Diabetic Nephropathy by Inhibiting Renal Fibrosis via TGF-β/Smad2/3 Pathway

Among all the complications of diabetes, diabetic nephropathy is a significant factor causing the end-stage renal disease associated with high death rates. Current treatment fails to produce an ideal outcome. Thus, searching for a new preventive drug is urgently needed. Liuwei Dihuang pill (LDP), a popular ancient Chinese medicine (TCM) prescription, has been applied to treat DN-like syndromes according to TCM theory. Here, we had established an animal model with DN and LDP therapy was put into use to assess its therapeutic effect in vivo. Our data showed that oxidative stress and TGF-β/Smad2/3 pathway-induced renal fibrosis could be observed in the DN animal model. However, the treatment of LDP impeded the generation of ROS and attenuated renal fibrosis-related proteins in damaged kidneys through interference in the TGF-β/Smad3 pathway. Our results indicated that LDP attenuated oxidative stress, accompanied by preventing the production of renal fibrosis through inhibiting the TGF-β/Smad2/3 pathway.

Exercise Therapy for People With Sarcopenic Obesity: Myokines and Adipokines as Effective Actors

Sarcopenic obesity is defined as a multifactorial disease in aging with decreased body muscle, decreased muscle strength, decreased independence, increased fat mass, due to decreased physical activity, changes in adipokines and myokines, and decreased satellite cells. People with sarcopenic obesity cause harmful changes in myokines and adipokines. These changes are due to a decrease interleukin-10 (IL-10), interleukin-15 (IL-15), insulin-like growth factor hormone (IGF-1), irisin, leukemia inhibitory factor (LIF), fibroblast growth factor-21 (FGF-21), adiponectin, and apelin. While factors such as myostatin, leptin, interleukin-6 (IL-6), interleukin-8 (IL-8), and resistin increase. The consequences of these changes are an increase in inflammatory factors, increased degradation of muscle proteins, increased fat mass, and decreased muscle tissue, which exacerbates sarcopenia obesity. In contrast, exercise, especially strength training, reverses this process, which includes increasing muscle protein synthesis, increasing myogenesis, increasing mitochondrial biogenesis, increasing brown fat, reducing white fat, reducing inflammatory factors, and reducing muscle atrophy. Since some people with chronic diseases are not able to do high-intensity strength training, exercises with blood flow restriction (BFR) are newly recommended. Numerous studies have shown that low-intensity BFR training produces the same increase in hypertrophy and muscle strength such as high-intensity strength training. Therefore, it seems that exercise interventions with BFR can be an effective way to prevent the exacerbation of sarcopenia obesity. However, due to limited studies on adipokines and exercises with BFR in people with sarcopenic obesity, more research is needed.

Unveiling the role of exercise training in targeting the inflammatory paradigm of heart failure with preserved ejection fraction: a narrative review

Heart failure with preserved ejection fraction (HFpEF) is currently lacking an effective pharmacological treatment with impact on major outcomes such as hospitalization and mortality. Exercise training (EXT) is recognized as an important nonpharmacological tool, capable of improving exercise capacity and quality of life, and has even been associated with a reduction in hospitalization and cardiovascular mortality risk. However, this positive impact largely lacks a physiological explanation. The aim of this narrative review was to provide an overview of the available data supporting the hypothesis that the beneficial role of EXT in HFpEF might be due to its effects on targeting the inflammatory paradigm described for this disease. A comprehensive literature search was conducted using the PubMed-NCBI database. We reviewed the effects of EXT throughout each step of the pathophysiological pathway leading to HFpEF and found clinical and/or preclinical evidence supporting the reduction of systemic inflammation, endothelial dysfunction, microvascular rarefaction, and myocardial stiffness. We also highlighted some gaps in the knowledge or topics that deserve further clarification in future studies. In conclusion, despite the scarcity of clinical studies in this population, there is compelling evidence suggesting that EXT modulates crucial aspects of the inflammatory pathway described for HFpEF and future investigation on cellular and molecular mechanisms are encouraged.

Effects of the hydroalcoholic extract of Rosa damascena on hippocampal long-term potentiation in rats fed high-fat diet

High-fat diets (HFDs) and obesity can cause serious health problems, such as neurodegenerative diseases and cognitive impairments. Consumption of HFD is associated with reduction in hippocampal synaptic plasticity. Rosa damascena (R. damascena) is traditionally used as a dietary supplement for many disorders. This study was carried out to determine the beneficial effect of hydroalcoholic extract of R. damascena on in vivo hippocampal synaptic plasticity (long-term potentiation, LTP) in the perforant pathway (PP)-dentate gyrus (DG) pathway in rats fed with an HFD. Male Wistar rats were randomly assigned to four groups: Control, R. damascena extract (1 g/kg bw daily for 30 days), HFD (for 90 days) and HFD + extract. The population spike (PS) amplitude and slope of excitatory post-synaptic potentials (EPSP) were measured in DG area in response to stimulation applied to the PP. Serum oxidative stress biomarkers [total thiol group (TTG) and superoxide dismutase (SOD)] were measured. The results showed the HFD impaired LTP induction in the PP-DG synapses. This conclusion is supported by decreased EPSP slope and PS amplitude of LTP. R. damascena supplementation in HFD animals enhanced EPSP slope and PS amplitude of LTP in the granular cell of DG. Consumption of HFD decreased TTG and SOD. R. damascena extract consumption in the HFD animals enhanced TTG and SOD. These data indicate that R. damascena dietary supplementation can ameliorate HFD-induced alteration of synaptic plasticity, probably through its significant antioxidant effects and activate signalling pathways, which are critical in controlling synaptic plasticity.

SIS3, a good candidate for the reverse of type 2 diabetes mellitus in mice

TGF-β signaling plays an extremely important role in the occurrence and development of type 2 diabetes mellitus (T2DM), and the blockade of TGF-β/Smad3 pathway protests against the high-fat diet-induced obesity and diabetes. As a specific small molecule inhibitor of Smad3 protein, the biological activities of compound SIS3 were evaluated by high-fat diet-induced T2DM model mice. In vivo results indicated that SIS3 can not only significantly reduce the body weight, fat mass, and fasting blood glucose in high-fat diet-induced T2DM model mice, but also improve insulin sensitivity and oral glucose tolerance of high-fat diet-induced T2DM model mice after the injection of SIS3 with 5 mg/kg for 45 days.

Quercetin reduces tendon adhesion in rat through suppression of oxidative stress

Background

Tendon adhesion is one of the most common clinical problems, which poses a considerable challenge to orthopedics doctors. Quercetin (QUE) as a popular drug at present, it has various biological functions, including anti-inflammatory, anti-ischemic, anti-peroxidation, and antioxidant. The purpose of this study was to investigate the effect of quercetin on tendon adhesion and whether quercetin can inhibit oxidative stress.

Method

Thirty-six rats were randomly divided into three groups, including control group, low QUE (50 mg/kg/day) group, and high QUE (100 mg/kg/day) group. After 1 week, the levels of SOD, MDA and GPx were measured. The degree of tendon adhesion was assessed by macroscopic evaluation and histological evaluation. After 4 weeks. Besides, the pharmacological toxicity of quercetin to main organs were evaluated by histological analysis.

Results

The extent of superoxide dismutase (SOD) and glutathione peroxidase (GPx) of tendon tissue in high QUE group was significantly higher than those of low QUE group and control group. And the extent of malondialdehyde (MDA) of tendon tissue in high QUE group was significantly lower than that of low QUE group and control group. By macroscopic evaluation and histological analysis, the extent of tendon adhesion in high QUE group was lower than low QUE group and control group. However, there were no significant changes of the major organs through histological analysis.

Conclusions

Quercetin may be a good and safe strategy in preventing tendon adhesion. But further clinical research is needed before its recommendation in the prevention and treatment of tendon adhesion.

25-OH-PPD inhibits hypertrophy on diabetic cardiomyopathy via the PI3k/Akt/GSK-3β signaling pathway

The present study investigated the inhibitory effects and the associated mechanism of the compound 25-OH-PPD (PPD) on cardiac hypertrophy, fibrosis and inflammation. The signaling pathways associated with diabetic mellitus cardiomyopathy (DMCM) were investigated using a rat model. DMCM Sprague-Dawley rats were induced by injection of streptozotocin. The animals were divided into 5 groups as follows: Normal group (NG group), diabetic group, PPD treatment group, PPD/LY294002 group (inhibitor of PI3K/Akt) and PPD/LiCl group [inhibitor of glycogen synthase kinase (GSK) 3β]. The studies were carried out during the 12 weeks following induction of diabetes and the levels of plasma brain natriuretic peptide (BNP), creatine phosphokinase isoenzyme (CK-MB) were measured. In addition, the volume of myocardial collagen fraction (CVF) was tested. The expression levels of the inflammatory cytokines, including transforming growth factor beta 1 (TGF-β1), connective tissue growth factor (CTGF), cell adhesion molecules α-smooth muscle actin (α-SMA) and vascular adhesion molecule 1 (VCAM-1) and associated signaling proteins (Akt, GSK-3β) were measured by biochemical analyses. The levels of BNP and CK-MB, the volume of CVF, the expression levels of TGF-β1, CTGF, α-SMA and VCAM-1 in the diabetic group were higher compared with those of the normal control group (P<0.05). Conversely, the levels of these molecules were significantly decreased in the PPD treatment groups (P<0.05). The aforementioned effects were partially eliminated in the PPD/LY294002 and PPD/LiCl groups. In addition, PPD treatment significantly increased the expression levels of p-Akt and decreased the levels of phosphorylated GSK-3β compared with those of the DMCM group (P<0.05). The data demonstrated that the protective effects of 25-OH-PPD against DMCM may be attributed to the PI3k/Akt/GSK-3β signaling pathway, via the suppression of the α-SMA/VCAM axis and the downregulation of TGF-β1 and CTGF expression.

Exercise training suppresses Mst1 activation and attenuates myocardial dysfunction in mice with type 1 diabetes

Our study was to test the effects of aerobic exercise on myocardial function in mice with type 1 diabetes and investigate the underlying mechanism associated with mammalian sterile 20-like kinase 1 (Mst1). Wild-type mice and Mst1(-/-) mice were injected with streptozotocin to induce diabetes and given moderate-intensity exercise for 12 weeks. Phosphorylation of Mst1 was significantly enhanced in the left ventricles of diabetic mice, which was reversed by exercise training. Exercise training or Mst1 deficiency improved myocardial function and reduced myocardial fibrosis in diabetic mice. Exercise training or Mst1 deficiency reduced TUNEL-positive cells and caspase-3 activity in the myocardium of diabetic mice. Exercise training or Mst1 deficiency abated oxidative stress and reduced mitochondrial reactive oxygen species formation, attenuated mitochondrial swelling, and enhanced mitochondrial adenosine triphosphate formation and mitochondrial membrane potential in the myocardium of diabetic mice. Exercise training or Mst1 deficiency suppressed inflammation in the myocardium of diabetic mice. Furthermore, exercise training did not provide further protection in Mst1 knockout mice in diabetes. In conclusion, chronic exercise training attenuated myocardial dysfunction in mice with type 1 diabetes, at least in part, through suppressing Mst1 activation.

Effects of Hypericum scabrum extract on dentate gyrus synaptic plasticity in high fat diet-fed rats

High-fat diet (HFD) can induce deficits in neural function, oxidative stress, and decrease hippocampal neurogenesis. Hypericum (H.) scabrum extract (Ext) contains compounds that could treat neurological disorders. This study aimed to examine the neuroprotective impacts of the H. scabrum Ext on hippocampal synaptic plasticity in rats that were fed HFD. Fifty-four male Wistar rats (220 ± 10 g) were randomly arranged in six groups: (1) HFD group; (2) HFD + Ext300 group; (3) HFD + Ext100 group; (4) Control group; (5) Ext 300 mg/kg group; (6) Ext 100 mg/kg group. These protocols were administrated for 3 months. After this stage, a stimulating electrode was implanted in the perforant pathway (PP), and a bipolar recording electrode was embedded into the dentate gyrus (DG). Long-term potentiation (LTP) was provoked by high-frequency stimulation (HFS) of the PP. Field excitatory postsynaptic potentials (EPSP) and population spikes (PS) were recorded at 5, 30, and 60 min after HFS. The HFD group exhibited a large and significant decrease in their PS amplitude and EPSP slope as compared to the control and extract groups. In reverse, H. scabrum administration in the HFD + Ext rats reversed the effect of HFD on the PS amplitude and EPSP slope. The results of the study support that H. scabrum Ext can inhibit diminished synaptic plasticity caused by the HFD. These effects are probably due to the extreme antioxidant impacts of the Ext and its capability to scavenge free radicals.

Porcine models for studying complications and organ crosstalk in diabetes mellitus

The worldwide prevalence of diabetes mellitus and obesity is rapidly increasing not only in adults but also in children and adolescents. Diabetes is associated with macrovascular complications increasing the risk for cardiovascular disease and stroke, as well as microvascular complications leading to diabetic nephropathy, retinopathy and neuropathy. Animal models are essential for studying disease mechanisms and for developing and testing diagnostic procedures and therapeutic strategies. Rodent models are most widely used but have limitations in translational research. Porcine models have the potential to bridge the gap between basic studies and clinical trials in human patients. This article provides an overview of concepts for the development of porcine models for diabetes and obesity research, with a focus on genetically engineered models. Diabetes-associated ocular, cardiovascular and renal alterations observed in diabetic pig models are summarized and their similarities with complications in diabetic patients are discussed. Systematic multi-organ biobanking of porcine models of diabetes and obesity and molecular profiling of representative tissue samples on different levels, e.g., on the transcriptome, proteome, or metabolome level, is proposed as a strategy for discovering tissue-specific pathomechanisms and their molecular key drivers using systems biology tools. This is exemplified by a recent study providing multi-omics insights into functional changes of the liver in a transgenic pig model for insulin-deficient diabetes mellitus. Collectively, these approaches will provide a better understanding of organ crosstalk in diabetes mellitus and eventually reveal new molecular targets for the prevention, early diagnosis and treatment of diabetes mellitus and its associated complications.